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linux-surface/patches/5.12/0006-surface-sam.patch
Maximilian Luz de116c5fd5
Update v5.12 patches 
Changes:
 - SAM:
   - Add support for Surface Laptop 4
     - Fix legacy PIC initialization issue
     - Add missing device IDs for GPIO controller and UARTs
   - Small code fixes

 - Cameras:
   - Fix for subdevice properties

Links:
 - kernel: 0c2ae61563
 - SAM: 0b52307159
2021-05-11 19:54:25 +02:00

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From 034c10f7c04684bba28833b3b8136368c9dc7527 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:34 +0100
Subject: [PATCH] platform/surface: Set up Surface Aggregator device registry
The Surface System Aggregator Module (SSAM) subsystem provides various
functionalities, which are separated by spreading them across multiple
devices and corresponding drivers. Parts of that functionality / some of
those devices, however, can (as far as we currently know) not be
auto-detected by conventional means. While older (specifically 5th- and
6th-)generation models do advertise most of their functionality via
standard platform devices in ACPI, newer generations do not.
As we are currently also not aware of any feasible way to query said
functionalities dynamically, this poses a problem. There is, however, a
device in ACPI that seems to be used by Windows for identifying
different Surface models: The Windows Surface Integration Device (WSID).
This device seems to have a HID corresponding to the overall set of
functionalities SSAM provides for the associated model.
This commit introduces a registry providing non-detectable device
information via software nodes. In addition, a SSAM platform hub driver
is introduced, which takes care of creating and managing the SSAM
devices specified in this registry. This approach allows for a
hierarchical setup akin to ACPI and is easily extendable, e.g. via
firmware node properties.
Note that this commit only provides the basis for the platform hub and
registry, and does not add any content to it. The registry will be
expanded in subsequent commits.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-2-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
MAINTAINERS | 1 +
drivers/platform/surface/Kconfig | 27 ++
drivers/platform/surface/Makefile | 1 +
.../surface/surface_aggregator_registry.c | 284 ++++++++++++++++++
4 files changed, 313 insertions(+)
create mode 100644 drivers/platform/surface/surface_aggregator_registry.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 9450e052f1b1..f6c524630575 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11904,6 +11904,7 @@ F: Documentation/driver-api/surface_aggregator/
F: drivers/platform/surface/aggregator/
F: drivers/platform/surface/surface_acpi_notify.c
F: drivers/platform/surface/surface_aggregator_cdev.c
+F: drivers/platform/surface/surface_aggregator_registry.c
F: include/linux/surface_acpi_notify.h
F: include/linux/surface_aggregator/
F: include/uapi/linux/surface_aggregator/
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index fd45940ab6ce..c51c55204b5f 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -77,6 +77,33 @@ config SURFACE_AGGREGATOR_CDEV
The provided interface is intended for debugging and development only,
and should not be used otherwise.
+config SURFACE_AGGREGATOR_REGISTRY
+ tristate "Surface System Aggregator Module Device Registry"
+ depends on SURFACE_AGGREGATOR
+ depends on SURFACE_AGGREGATOR_BUS
+ help
+ Device-registry and device-hubs for Surface System Aggregator Module
+ (SSAM) devices.
+
+ Provides a module and driver which act as a device-registry for SSAM
+ client devices that cannot be detected automatically, e.g. via ACPI.
+ Such devices are instead provided via this registry and attached via
+ device hubs, also provided in this module.
+
+ Devices provided via this registry are:
+ - Platform profile (performance-/cooling-mode) device (5th- and later
+ generations).
+ - Battery/AC devices (7th-generation).
+ - HID input devices (7th-generation).
+
+ Select M (recommended) or Y here if you want support for the above
+ mentioned devices on the corresponding Surface models. Without this
+ module, the respective devices will not be instantiated and thus any
+ functionality provided by them will be missing, even when drivers for
+ these devices are present. In other words, this module only provides
+ the respective client devices. Drivers for these devices still need to
+ be selected via the other options.
+
config SURFACE_BOOK1_DGPU_SWITCH
tristate "Surface Book 1 dGPU Switch Driver"
depends on SYSFS
diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile
index 6b69175598ab..ed12676f06e6 100644
--- a/drivers/platform/surface/Makefile
+++ b/drivers/platform/surface/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_SURFACE_3_POWER_OPREGION) += surface3_power.o
obj-$(CONFIG_SURFACE_ACPI_NOTIFY) += surface_acpi_notify.o
obj-$(CONFIG_SURFACE_AGGREGATOR) += aggregator/
obj-$(CONFIG_SURFACE_AGGREGATOR_CDEV) += surface_aggregator_cdev.o
+obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o
obj-$(CONFIG_SURFACE_BOOK1_DGPU_SWITCH) += surfacebook1_dgpu_switch.o
obj-$(CONFIG_SURFACE_GPE) += surface_gpe.o
obj-$(CONFIG_SURFACE_HOTPLUG) += surface_hotplug.o
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
new file mode 100644
index 000000000000..a051d941ad96
--- /dev/null
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface System Aggregator Module (SSAM) client device registry.
+ *
+ * Registry for non-platform/non-ACPI SSAM client devices, i.e. devices that
+ * cannot be auto-detected. Provides device-hubs and performs instantiation
+ * for these devices.
+ *
+ * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
+
+
+/* -- Device registry. ------------------------------------------------------ */
+
+/*
+ * SSAM device names follow the SSAM module alias, meaning they are prefixed
+ * with 'ssam:', followed by domain, category, target ID, instance ID, and
+ * function, each encoded as two-digit hexadecimal, separated by ':'. In other
+ * words, it follows the scheme
+ *
+ * ssam:dd:cc:tt:ii:ff
+ *
+ * Where, 'dd', 'cc', 'tt', 'ii', and 'ff' are the two-digit hexadecimal
+ * values mentioned above, respectively.
+ */
+
+/* Root node. */
+static const struct software_node ssam_node_root = {
+ .name = "ssam_platform_hub",
+};
+
+/* Devices for Surface Book 2. */
+static const struct software_node *ssam_node_group_sb2[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Book 3. */
+static const struct software_node *ssam_node_group_sb3[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Laptop 1. */
+static const struct software_node *ssam_node_group_sl1[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Laptop 2. */
+static const struct software_node *ssam_node_group_sl2[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Laptop 3. */
+static const struct software_node *ssam_node_group_sl3[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Laptop Go. */
+static const struct software_node *ssam_node_group_slg1[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Pro 5. */
+static const struct software_node *ssam_node_group_sp5[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Pro 6. */
+static const struct software_node *ssam_node_group_sp6[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+/* Devices for Surface Pro 7. */
+static const struct software_node *ssam_node_group_sp7[] = {
+ &ssam_node_root,
+ NULL,
+};
+
+
+/* -- Device registry helper functions. ------------------------------------- */
+
+static int ssam_uid_from_string(const char *str, struct ssam_device_uid *uid)
+{
+ u8 d, tc, tid, iid, fn;
+ int n;
+
+ n = sscanf(str, "ssam:%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn);
+ if (n != 5)
+ return -EINVAL;
+
+ uid->domain = d;
+ uid->category = tc;
+ uid->target = tid;
+ uid->instance = iid;
+ uid->function = fn;
+
+ return 0;
+}
+
+static int ssam_hub_remove_devices_fn(struct device *dev, void *data)
+{
+ if (!is_ssam_device(dev))
+ return 0;
+
+ ssam_device_remove(to_ssam_device(dev));
+ return 0;
+}
+
+static void ssam_hub_remove_devices(struct device *parent)
+{
+ device_for_each_child_reverse(parent, NULL, ssam_hub_remove_devices_fn);
+}
+
+static int ssam_hub_add_device(struct device *parent, struct ssam_controller *ctrl,
+ struct fwnode_handle *node)
+{
+ struct ssam_device_uid uid;
+ struct ssam_device *sdev;
+ int status;
+
+ status = ssam_uid_from_string(fwnode_get_name(node), &uid);
+ if (status)
+ return status;
+
+ sdev = ssam_device_alloc(ctrl, uid);
+ if (!sdev)
+ return -ENOMEM;
+
+ sdev->dev.parent = parent;
+ sdev->dev.fwnode = node;
+
+ status = ssam_device_add(sdev);
+ if (status)
+ ssam_device_put(sdev);
+
+ return status;
+}
+
+static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *ctrl,
+ struct fwnode_handle *node)
+{
+ struct fwnode_handle *child;
+ int status;
+
+ fwnode_for_each_child_node(node, child) {
+ /*
+ * Try to add the device specified in the firmware node. If
+ * this fails with -EINVAL, the node does not specify any SSAM
+ * device, so ignore it and continue with the next one.
+ */
+
+ status = ssam_hub_add_device(parent, ctrl, child);
+ if (status && status != -EINVAL)
+ goto err;
+ }
+
+ return 0;
+err:
+ ssam_hub_remove_devices(parent);
+ return status;
+}
+
+
+/* -- SSAM platform/meta-hub driver. ---------------------------------------- */
+
+static const struct acpi_device_id ssam_platform_hub_match[] = {
+ /* Surface Pro 4, 5, and 6 (OMBR < 0x10) */
+ { "MSHW0081", (unsigned long)ssam_node_group_sp5 },
+
+ /* Surface Pro 6 (OMBR >= 0x10) */
+ { "MSHW0111", (unsigned long)ssam_node_group_sp6 },
+
+ /* Surface Pro 7 */
+ { "MSHW0116", (unsigned long)ssam_node_group_sp7 },
+
+ /* Surface Book 2 */
+ { "MSHW0107", (unsigned long)ssam_node_group_sb2 },
+
+ /* Surface Book 3 */
+ { "MSHW0117", (unsigned long)ssam_node_group_sb3 },
+
+ /* Surface Laptop 1 */
+ { "MSHW0086", (unsigned long)ssam_node_group_sl1 },
+
+ /* Surface Laptop 2 */
+ { "MSHW0112", (unsigned long)ssam_node_group_sl2 },
+
+ /* Surface Laptop 3 (13", Intel) */
+ { "MSHW0114", (unsigned long)ssam_node_group_sl3 },
+
+ /* Surface Laptop 3 (15", AMD) */
+ { "MSHW0110", (unsigned long)ssam_node_group_sl3 },
+
+ /* Surface Laptop Go 1 */
+ { "MSHW0118", (unsigned long)ssam_node_group_slg1 },
+
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, ssam_platform_hub_match);
+
+static int ssam_platform_hub_probe(struct platform_device *pdev)
+{
+ const struct software_node **nodes;
+ struct ssam_controller *ctrl;
+ struct fwnode_handle *root;
+ int status;
+
+ nodes = (const struct software_node **)acpi_device_get_match_data(&pdev->dev);
+ if (!nodes)
+ return -ENODEV;
+
+ /*
+ * As we're adding the SSAM client devices as children under this device
+ * and not the SSAM controller, we need to add a device link to the
+ * controller to ensure that we remove all of our devices before the
+ * controller is removed. This also guarantees proper ordering for
+ * suspend/resume of the devices on this hub.
+ */
+ ctrl = ssam_client_bind(&pdev->dev);
+ if (IS_ERR(ctrl))
+ return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl);
+
+ status = software_node_register_node_group(nodes);
+ if (status)
+ return status;
+
+ root = software_node_fwnode(&ssam_node_root);
+ if (!root) {
+ software_node_unregister_node_group(nodes);
+ return -ENOENT;
+ }
+
+ set_secondary_fwnode(&pdev->dev, root);
+
+ status = ssam_hub_add_devices(&pdev->dev, ctrl, root);
+ if (status) {
+ set_secondary_fwnode(&pdev->dev, NULL);
+ software_node_unregister_node_group(nodes);
+ }
+
+ platform_set_drvdata(pdev, nodes);
+ return status;
+}
+
+static int ssam_platform_hub_remove(struct platform_device *pdev)
+{
+ const struct software_node **nodes = platform_get_drvdata(pdev);
+
+ ssam_hub_remove_devices(&pdev->dev);
+ set_secondary_fwnode(&pdev->dev, NULL);
+ software_node_unregister_node_group(nodes);
+ return 0;
+}
+
+static struct platform_driver ssam_platform_hub_driver = {
+ .probe = ssam_platform_hub_probe,
+ .remove = ssam_platform_hub_remove,
+ .driver = {
+ .name = "surface_aggregator_platform_hub",
+ .acpi_match_table = ssam_platform_hub_match,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_platform_driver(ssam_platform_hub_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
--
2.31.1
From a09281921a27087db2d48580b5c09e56f62db2cd Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:35 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add base device hub
The Surface Book 3 has a detachable base part. While the top part
(so-called clipboard) contains the CPU, touchscreen, and primary
battery, the base contains, among other things, a keyboard, touchpad,
and secondary battery.
Those devices do not react well to being accessed when the base part is
detached and should thus be removed and added in sync with the base. To
facilitate this, we introduce a virtual base device hub, which
automatically removes or adds the devices registered under it.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-3-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface/surface_aggregator_registry.c | 261 +++++++++++++++++-
1 file changed, 260 insertions(+), 1 deletion(-)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index a051d941ad96..6c23d75a044c 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -11,9 +11,12 @@
#include <linux/acpi.h>
#include <linux/kernel.h>
+#include <linux/limits.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/property.h>
+#include <linux/types.h>
#include <linux/surface_aggregator/controller.h>
#include <linux/surface_aggregator/device.h>
@@ -38,6 +41,12 @@ static const struct software_node ssam_node_root = {
.name = "ssam_platform_hub",
};
+/* Base device hub (devices attached to Surface Book 3 base). */
+static const struct software_node ssam_node_hub_base = {
+ .name = "ssam:00:00:02:00:00",
+ .parent = &ssam_node_root,
+};
+
/* Devices for Surface Book 2. */
static const struct software_node *ssam_node_group_sb2[] = {
&ssam_node_root,
@@ -47,6 +56,7 @@ static const struct software_node *ssam_node_group_sb2[] = {
/* Devices for Surface Book 3. */
static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_root,
+ &ssam_node_hub_base,
NULL,
};
@@ -177,6 +187,230 @@ static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *c
}
+/* -- SSAM base-hub driver. ------------------------------------------------- */
+
+enum ssam_base_hub_state {
+ SSAM_BASE_HUB_UNINITIALIZED,
+ SSAM_BASE_HUB_CONNECTED,
+ SSAM_BASE_HUB_DISCONNECTED,
+};
+
+struct ssam_base_hub {
+ struct ssam_device *sdev;
+
+ struct mutex lock; /* Guards state update checks and transitions. */
+ enum ssam_base_hub_state state;
+
+ struct ssam_event_notifier notif;
+};
+
+static SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x0d,
+ .instance_id = 0x00,
+});
+
+#define SSAM_BAS_OPMODE_TABLET 0x00
+#define SSAM_EVENT_BAS_CID_CONNECTION 0x0c
+
+static int ssam_base_hub_query_state(struct ssam_base_hub *hub, enum ssam_base_hub_state *state)
+{
+ u8 opmode;
+ int status;
+
+ status = ssam_retry(ssam_bas_query_opmode, hub->sdev->ctrl, &opmode);
+ if (status < 0) {
+ dev_err(&hub->sdev->dev, "failed to query base state: %d\n", status);
+ return status;
+ }
+
+ if (opmode != SSAM_BAS_OPMODE_TABLET)
+ *state = SSAM_BASE_HUB_CONNECTED;
+ else
+ *state = SSAM_BASE_HUB_DISCONNECTED;
+
+ return 0;
+}
+
+static ssize_t ssam_base_hub_state_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct ssam_base_hub *hub = dev_get_drvdata(dev);
+ bool connected;
+
+ mutex_lock(&hub->lock);
+ connected = hub->state == SSAM_BASE_HUB_CONNECTED;
+ mutex_unlock(&hub->lock);
+
+ return sysfs_emit(buf, "%d\n", connected);
+}
+
+static struct device_attribute ssam_base_hub_attr_state =
+ __ATTR(state, 0444, ssam_base_hub_state_show, NULL);
+
+static struct attribute *ssam_base_hub_attrs[] = {
+ &ssam_base_hub_attr_state.attr,
+ NULL,
+};
+
+const struct attribute_group ssam_base_hub_group = {
+ .attrs = ssam_base_hub_attrs,
+};
+
+static int __ssam_base_hub_update(struct ssam_base_hub *hub, enum ssam_base_hub_state new)
+{
+ struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
+ int status = 0;
+
+ lockdep_assert_held(&hub->lock);
+
+ if (hub->state == new)
+ return 0;
+ hub->state = new;
+
+ if (hub->state == SSAM_BASE_HUB_CONNECTED)
+ status = ssam_hub_add_devices(&hub->sdev->dev, hub->sdev->ctrl, node);
+ else
+ ssam_hub_remove_devices(&hub->sdev->dev);
+
+ if (status)
+ dev_err(&hub->sdev->dev, "failed to update base-hub devices: %d\n", status);
+
+ return status;
+}
+
+static int ssam_base_hub_update(struct ssam_base_hub *hub)
+{
+ enum ssam_base_hub_state state;
+ int status;
+
+ mutex_lock(&hub->lock);
+
+ status = ssam_base_hub_query_state(hub, &state);
+ if (!status)
+ status = __ssam_base_hub_update(hub, state);
+
+ mutex_unlock(&hub->lock);
+ return status;
+}
+
+static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+ struct ssam_base_hub *hub;
+ struct ssam_device *sdev;
+ enum ssam_base_hub_state new;
+
+ hub = container_of(nf, struct ssam_base_hub, notif);
+ sdev = hub->sdev;
+
+ if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
+ return 0;
+
+ if (event->length < 1) {
+ dev_err(&sdev->dev, "unexpected payload size: %u\n",
+ event->length);
+ return 0;
+ }
+
+ if (event->data[0])
+ new = SSAM_BASE_HUB_CONNECTED;
+ else
+ new = SSAM_BASE_HUB_DISCONNECTED;
+
+ mutex_lock(&hub->lock);
+ __ssam_base_hub_update(hub, new);
+ mutex_unlock(&hub->lock);
+
+ /*
+ * Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
+ * consumed by the detachment system driver. We're just a (more or less)
+ * silent observer.
+ */
+ return 0;
+}
+
+static int __maybe_unused ssam_base_hub_resume(struct device *dev)
+{
+ return ssam_base_hub_update(dev_get_drvdata(dev));
+}
+static SIMPLE_DEV_PM_OPS(ssam_base_hub_pm_ops, NULL, ssam_base_hub_resume);
+
+static int ssam_base_hub_probe(struct ssam_device *sdev)
+{
+ struct ssam_base_hub *hub;
+ int status;
+
+ hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
+ if (!hub)
+ return -ENOMEM;
+
+ mutex_init(&hub->lock);
+
+ hub->sdev = sdev;
+ hub->state = SSAM_BASE_HUB_UNINITIALIZED;
+
+ hub->notif.base.priority = INT_MAX; /* This notifier should run first. */
+ hub->notif.base.fn = ssam_base_hub_notif;
+ hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
+ hub->notif.event.id.target_category = SSAM_SSH_TC_BAS,
+ hub->notif.event.id.instance = 0,
+ hub->notif.event.mask = SSAM_EVENT_MASK_NONE;
+ hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+ ssam_device_set_drvdata(sdev, hub);
+
+ status = ssam_notifier_register(sdev->ctrl, &hub->notif);
+ if (status)
+ goto err_register;
+
+ status = ssam_base_hub_update(hub);
+ if (status)
+ goto err_update;
+
+ status = sysfs_create_group(&sdev->dev.kobj, &ssam_base_hub_group);
+ if (status)
+ goto err_update;
+
+ return 0;
+
+err_update:
+ ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+ ssam_hub_remove_devices(&sdev->dev);
+err_register:
+ mutex_destroy(&hub->lock);
+ return status;
+}
+
+static void ssam_base_hub_remove(struct ssam_device *sdev)
+{
+ struct ssam_base_hub *hub = ssam_device_get_drvdata(sdev);
+
+ sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group);
+
+ ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+ ssam_hub_remove_devices(&sdev->dev);
+
+ mutex_destroy(&hub->lock);
+}
+
+static const struct ssam_device_id ssam_base_hub_match[] = {
+ { SSAM_VDEV(HUB, 0x02, SSAM_ANY_IID, 0x00) },
+ { },
+};
+
+static struct ssam_device_driver ssam_base_hub_driver = {
+ .probe = ssam_base_hub_probe,
+ .remove = ssam_base_hub_remove,
+ .match_table = ssam_base_hub_match,
+ .driver = {
+ .name = "surface_aggregator_base_hub",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ .pm = &ssam_base_hub_pm_ops,
+ },
+};
+
+
/* -- SSAM platform/meta-hub driver. ---------------------------------------- */
static const struct acpi_device_id ssam_platform_hub_match[] = {
@@ -277,7 +511,32 @@ static struct platform_driver ssam_platform_hub_driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
-module_platform_driver(ssam_platform_hub_driver);
+
+
+/* -- Module initialization. ------------------------------------------------ */
+
+static int __init ssam_device_hub_init(void)
+{
+ int status;
+
+ status = platform_driver_register(&ssam_platform_hub_driver);
+ if (status)
+ return status;
+
+ status = ssam_device_driver_register(&ssam_base_hub_driver);
+ if (status)
+ platform_driver_unregister(&ssam_platform_hub_driver);
+
+ return status;
+}
+module_init(ssam_device_hub_init);
+
+static void __exit ssam_device_hub_exit(void)
+{
+ ssam_device_driver_unregister(&ssam_base_hub_driver);
+ platform_driver_unregister(&ssam_platform_hub_driver);
+}
+module_exit(ssam_device_hub_exit);
MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module");
--
2.31.1
From 482f1bc858fde2c6a1fd330548500f08589240c6 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:36 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add battery subsystem
devices
Add battery subsystem (TC=0x02) devices (battery and AC) to the SSAM
device registry. These devices need to be registered for 7th-generation
Surface models. On 5th- and 6th-generation models, these devices are
handled via the standard ACPI battery/AC interface, which in turn
accesses the same SSAM interface via the Surface ACPI Notify (SAN)
driver.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-4-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface/surface_aggregator_registry.c | 27 +++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 6c23d75a044c..cde279692842 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -47,6 +47,24 @@ static const struct software_node ssam_node_hub_base = {
.parent = &ssam_node_root,
};
+/* AC adapter. */
+static const struct software_node ssam_node_bat_ac = {
+ .name = "ssam:01:02:01:01:01",
+ .parent = &ssam_node_root,
+};
+
+/* Primary battery. */
+static const struct software_node ssam_node_bat_main = {
+ .name = "ssam:01:02:01:01:00",
+ .parent = &ssam_node_root,
+};
+
+/* Secondary battery (Surface Book 3). */
+static const struct software_node ssam_node_bat_sb3base = {
+ .name = "ssam:01:02:02:01:00",
+ .parent = &ssam_node_hub_base,
+};
+
/* Devices for Surface Book 2. */
static const struct software_node *ssam_node_group_sb2[] = {
&ssam_node_root,
@@ -57,6 +75,9 @@ static const struct software_node *ssam_node_group_sb2[] = {
static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_root,
&ssam_node_hub_base,
+ &ssam_node_bat_ac,
+ &ssam_node_bat_main,
+ &ssam_node_bat_sb3base,
NULL,
};
@@ -75,12 +96,16 @@ static const struct software_node *ssam_node_group_sl2[] = {
/* Devices for Surface Laptop 3. */
static const struct software_node *ssam_node_group_sl3[] = {
&ssam_node_root,
+ &ssam_node_bat_ac,
+ &ssam_node_bat_main,
NULL,
};
/* Devices for Surface Laptop Go. */
static const struct software_node *ssam_node_group_slg1[] = {
&ssam_node_root,
+ &ssam_node_bat_ac,
+ &ssam_node_bat_main,
NULL,
};
@@ -99,6 +124,8 @@ static const struct software_node *ssam_node_group_sp6[] = {
/* Devices for Surface Pro 7. */
static const struct software_node *ssam_node_group_sp7[] = {
&ssam_node_root,
+ &ssam_node_bat_ac,
+ &ssam_node_bat_main,
NULL,
};
--
2.31.1
From cdb9998251939f427f47b85846a5b1914f12b95c Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:37 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add platform profile
device
Add the SSAM platform profile device to the SSAM device registry. This
device is accessible under the thermal subsystem (TC=0x03) and needs to
be registered for all Surface models.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-5-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface/surface_aggregator_registry.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index cde279692842..33904613dd4b 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -65,9 +65,16 @@ static const struct software_node ssam_node_bat_sb3base = {
.parent = &ssam_node_hub_base,
};
+/* Platform profile / performance-mode device. */
+static const struct software_node ssam_node_tmp_pprof = {
+ .name = "ssam:01:03:01:00:01",
+ .parent = &ssam_node_root,
+};
+
/* Devices for Surface Book 2. */
static const struct software_node *ssam_node_group_sb2[] = {
&ssam_node_root,
+ &ssam_node_tmp_pprof,
NULL,
};
@@ -78,18 +85,21 @@ static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_bat_sb3base,
+ &ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Laptop 1. */
static const struct software_node *ssam_node_group_sl1[] = {
&ssam_node_root,
+ &ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Laptop 2. */
static const struct software_node *ssam_node_group_sl2[] = {
&ssam_node_root,
+ &ssam_node_tmp_pprof,
NULL,
};
@@ -98,6 +108,7 @@ static const struct software_node *ssam_node_group_sl3[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
+ &ssam_node_tmp_pprof,
NULL,
};
@@ -106,18 +117,21 @@ static const struct software_node *ssam_node_group_slg1[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
+ &ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Pro 5. */
static const struct software_node *ssam_node_group_sp5[] = {
&ssam_node_root,
+ &ssam_node_tmp_pprof,
NULL,
};
/* Devices for Surface Pro 6. */
static const struct software_node *ssam_node_group_sp6[] = {
&ssam_node_root,
+ &ssam_node_tmp_pprof,
NULL,
};
@@ -126,6 +140,7 @@ static const struct software_node *ssam_node_group_sp7[] = {
&ssam_node_root,
&ssam_node_bat_ac,
&ssam_node_bat_main,
+ &ssam_node_tmp_pprof,
NULL,
};
--
2.31.1
From d30d9a3f6fe43f497aed8eae6a559a5f191bbab6 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:38 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add DTX device
Add the detachment system (DTX) SSAM device for the Surface Book 3. This
device is accessible under the base (TC=0x11) subsystem.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-6-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/surface_aggregator_registry.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 33904613dd4b..dc044d06828b 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -71,6 +71,12 @@ static const struct software_node ssam_node_tmp_pprof = {
.parent = &ssam_node_root,
};
+/* DTX / detachment-system device (Surface Book 3). */
+static const struct software_node ssam_node_bas_dtx = {
+ .name = "ssam:01:11:01:00:00",
+ .parent = &ssam_node_root,
+};
+
/* Devices for Surface Book 2. */
static const struct software_node *ssam_node_group_sb2[] = {
&ssam_node_root,
@@ -86,6 +92,7 @@ static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_bat_main,
&ssam_node_bat_sb3base,
&ssam_node_tmp_pprof,
+ &ssam_node_bas_dtx,
NULL,
};
--
2.31.1
From f48e806ac0cb67eb06d61fc5adf4c7e5b7a89edd Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 12 Feb 2021 12:54:39 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add HID subsystem
devices
Add HID subsystem (TC=0x15) devices. These devices need to be registered
for 7th-generation Surface models. On previous generations, these
devices are either provided as platform devices via ACPI (Surface Laptop
1 and 2) or implemented as standard USB device.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210212115439.1525216-7-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface/surface_aggregator_registry.c | 49 +++++++++++++++++++
1 file changed, 49 insertions(+)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index dc044d06828b..caee90d135c5 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -77,6 +77,48 @@ static const struct software_node ssam_node_bas_dtx = {
.parent = &ssam_node_root,
};
+/* HID keyboard. */
+static const struct software_node ssam_node_hid_main_keyboard = {
+ .name = "ssam:01:15:02:01:00",
+ .parent = &ssam_node_root,
+};
+
+/* HID touchpad. */
+static const struct software_node ssam_node_hid_main_touchpad = {
+ .name = "ssam:01:15:02:03:00",
+ .parent = &ssam_node_root,
+};
+
+/* HID device instance 5 (unknown HID device). */
+static const struct software_node ssam_node_hid_main_iid5 = {
+ .name = "ssam:01:15:02:05:00",
+ .parent = &ssam_node_root,
+};
+
+/* HID keyboard (base hub). */
+static const struct software_node ssam_node_hid_base_keyboard = {
+ .name = "ssam:01:15:02:01:00",
+ .parent = &ssam_node_hub_base,
+};
+
+/* HID touchpad (base hub). */
+static const struct software_node ssam_node_hid_base_touchpad = {
+ .name = "ssam:01:15:02:03:00",
+ .parent = &ssam_node_hub_base,
+};
+
+/* HID device instance 5 (unknown HID device, base hub). */
+static const struct software_node ssam_node_hid_base_iid5 = {
+ .name = "ssam:01:15:02:05:00",
+ .parent = &ssam_node_hub_base,
+};
+
+/* HID device instance 6 (unknown HID device, base hub). */
+static const struct software_node ssam_node_hid_base_iid6 = {
+ .name = "ssam:01:15:02:06:00",
+ .parent = &ssam_node_hub_base,
+};
+
/* Devices for Surface Book 2. */
static const struct software_node *ssam_node_group_sb2[] = {
&ssam_node_root,
@@ -93,6 +135,10 @@ static const struct software_node *ssam_node_group_sb3[] = {
&ssam_node_bat_sb3base,
&ssam_node_tmp_pprof,
&ssam_node_bas_dtx,
+ &ssam_node_hid_base_keyboard,
+ &ssam_node_hid_base_touchpad,
+ &ssam_node_hid_base_iid5,
+ &ssam_node_hid_base_iid6,
NULL,
};
@@ -116,6 +162,9 @@ static const struct software_node *ssam_node_group_sl3[] = {
&ssam_node_bat_ac,
&ssam_node_bat_main,
&ssam_node_tmp_pprof,
+ &ssam_node_hid_main_keyboard,
+ &ssam_node_hid_main_touchpad,
+ &ssam_node_hid_main_iid5,
NULL,
};
--
2.31.1
From da7ab6cbc069aa979b548d4aafb571e0e4125318 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Thu, 11 Feb 2021 21:17:03 +0100
Subject: [PATCH] platform/surface: Add platform profile driver
Add a driver to provide platform profile support on 5th- and later
generation Microsoft Surface devices with a Surface System Aggregator
Module. On those devices, the platform profile can be used to influence
cooling behavior and power consumption.
For example, the default 'quiet' profile limits fan noise and in turn
sacrifices performance of the discrete GPU found on Surface Books. Its
full performance can only be unlocked on the 'performance' profile.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210211201703.658240-5-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
MAINTAINERS | 6 +
drivers/platform/surface/Kconfig | 22 ++
drivers/platform/surface/Makefile | 1 +
.../surface/surface_platform_profile.c | 190 ++++++++++++++++++
4 files changed, 219 insertions(+)
create mode 100644 drivers/platform/surface/surface_platform_profile.c
diff --git a/MAINTAINERS b/MAINTAINERS
index f6c524630575..fce5cdcefc0b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11889,6 +11889,12 @@ L: platform-driver-x86@vger.kernel.org
S: Maintained
F: drivers/platform/surface/surface_hotplug.c
+MICROSOFT SURFACE PLATFORM PROFILE DRIVER
+M: Maximilian Luz <luzmaximilian@gmail.com>
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/platform/surface/surface_platform_profile.c
+
MICROSOFT SURFACE PRO 3 BUTTON DRIVER
M: Chen Yu <yu.c.chen@intel.com>
L: platform-driver-x86@vger.kernel.org
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index c51c55204b5f..6fb304da845f 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -139,6 +139,28 @@ config SURFACE_HOTPLUG
Select M or Y here, if you want to (fully) support hot-plugging of
dGPU devices on the Surface Book 2 and/or 3 during D3cold.
+config SURFACE_PLATFORM_PROFILE
+ tristate "Surface Platform Profile Driver"
+ depends on SURFACE_AGGREGATOR_REGISTRY
+ select ACPI_PLATFORM_PROFILE
+ help
+ Provides support for the ACPI platform profile on 5th- and later
+ generation Microsoft Surface devices.
+
+ More specifically, this driver provides ACPI platform profile support
+ on Microsoft Surface devices with a Surface System Aggregator Module
+ (SSAM) connected via the Surface Serial Hub (SSH / SAM-over-SSH). In
+ other words, this driver provides platform profile support on the
+ Surface Pro 5, Surface Book 2, Surface Laptop, Surface Laptop Go and
+ later. On those devices, the platform profile can significantly
+ influence cooling behavior, e.g. setting it to 'quiet' (default) or
+ 'low-power' can significantly limit performance of the discrete GPU on
+ Surface Books, while in turn leading to lower power consumption and/or
+ less fan noise.
+
+ Select M or Y here, if you want to include ACPI platform profile
+ support on the above mentioned devices.
+
config SURFACE_PRO3_BUTTON
tristate "Power/home/volume buttons driver for Microsoft Surface Pro 3/4 tablet"
depends on INPUT
diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile
index ed12676f06e6..f7187bae1729 100644
--- a/drivers/platform/surface/Makefile
+++ b/drivers/platform/surface/Makefile
@@ -14,4 +14,5 @@ obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o
obj-$(CONFIG_SURFACE_BOOK1_DGPU_SWITCH) += surfacebook1_dgpu_switch.o
obj-$(CONFIG_SURFACE_GPE) += surface_gpe.o
obj-$(CONFIG_SURFACE_HOTPLUG) += surface_hotplug.o
+obj-$(CONFIG_SURFACE_PLATFORM_PROFILE) += surface_platform_profile.o
obj-$(CONFIG_SURFACE_PRO3_BUTTON) += surfacepro3_button.o
diff --git a/drivers/platform/surface/surface_platform_profile.c b/drivers/platform/surface/surface_platform_profile.c
new file mode 100644
index 000000000000..0081b01a5b0f
--- /dev/null
+++ b/drivers/platform/surface/surface_platform_profile.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface Platform Profile / Performance Mode driver for Surface System
+ * Aggregator Module (thermal subsystem).
+ *
+ * Copyright (C) 2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_profile.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/device.h>
+
+enum ssam_tmp_profile {
+ SSAM_TMP_PROFILE_NORMAL = 1,
+ SSAM_TMP_PROFILE_BATTERY_SAVER = 2,
+ SSAM_TMP_PROFILE_BETTER_PERFORMANCE = 3,
+ SSAM_TMP_PROFILE_BEST_PERFORMANCE = 4,
+};
+
+struct ssam_tmp_profile_info {
+ __le32 profile;
+ __le16 unknown1;
+ __le16 unknown2;
+} __packed;
+
+struct ssam_tmp_profile_device {
+ struct ssam_device *sdev;
+ struct platform_profile_handler handler;
+};
+
+static SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_profile_get, struct ssam_tmp_profile_info, {
+ .target_category = SSAM_SSH_TC_TMP,
+ .command_id = 0x02,
+});
+
+static SSAM_DEFINE_SYNC_REQUEST_CL_W(__ssam_tmp_profile_set, __le32, {
+ .target_category = SSAM_SSH_TC_TMP,
+ .command_id = 0x03,
+});
+
+static int ssam_tmp_profile_get(struct ssam_device *sdev, enum ssam_tmp_profile *p)
+{
+ struct ssam_tmp_profile_info info;
+ int status;
+
+ status = ssam_retry(__ssam_tmp_profile_get, sdev, &info);
+ if (status < 0)
+ return status;
+
+ *p = le32_to_cpu(info.profile);
+ return 0;
+}
+
+static int ssam_tmp_profile_set(struct ssam_device *sdev, enum ssam_tmp_profile p)
+{
+ __le32 profile_le = cpu_to_le32(p);
+
+ return ssam_retry(__ssam_tmp_profile_set, sdev, &profile_le);
+}
+
+static int convert_ssam_to_profile(struct ssam_device *sdev, enum ssam_tmp_profile p)
+{
+ switch (p) {
+ case SSAM_TMP_PROFILE_NORMAL:
+ return PLATFORM_PROFILE_BALANCED;
+
+ case SSAM_TMP_PROFILE_BATTERY_SAVER:
+ return PLATFORM_PROFILE_LOW_POWER;
+
+ case SSAM_TMP_PROFILE_BETTER_PERFORMANCE:
+ return PLATFORM_PROFILE_BALANCED_PERFORMANCE;
+
+ case SSAM_TMP_PROFILE_BEST_PERFORMANCE:
+ return PLATFORM_PROFILE_PERFORMANCE;
+
+ default:
+ dev_err(&sdev->dev, "invalid performance profile: %d", p);
+ return -EINVAL;
+ }
+}
+
+static int convert_profile_to_ssam(struct ssam_device *sdev, enum platform_profile_option p)
+{
+ switch (p) {
+ case PLATFORM_PROFILE_LOW_POWER:
+ return SSAM_TMP_PROFILE_BATTERY_SAVER;
+
+ case PLATFORM_PROFILE_BALANCED:
+ return SSAM_TMP_PROFILE_NORMAL;
+
+ case PLATFORM_PROFILE_BALANCED_PERFORMANCE:
+ return SSAM_TMP_PROFILE_BETTER_PERFORMANCE;
+
+ case PLATFORM_PROFILE_PERFORMANCE:
+ return SSAM_TMP_PROFILE_BEST_PERFORMANCE;
+
+ default:
+ /* This should have already been caught by platform_profile_store(). */
+ WARN(true, "unsupported platform profile");
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ssam_platform_profile_get(struct platform_profile_handler *pprof,
+ enum platform_profile_option *profile)
+{
+ struct ssam_tmp_profile_device *tpd;
+ enum ssam_tmp_profile tp;
+ int status;
+
+ tpd = container_of(pprof, struct ssam_tmp_profile_device, handler);
+
+ status = ssam_tmp_profile_get(tpd->sdev, &tp);
+ if (status)
+ return status;
+
+ status = convert_ssam_to_profile(tpd->sdev, tp);
+ if (status < 0)
+ return status;
+
+ *profile = status;
+ return 0;
+}
+
+static int ssam_platform_profile_set(struct platform_profile_handler *pprof,
+ enum platform_profile_option profile)
+{
+ struct ssam_tmp_profile_device *tpd;
+ int tp;
+
+ tpd = container_of(pprof, struct ssam_tmp_profile_device, handler);
+
+ tp = convert_profile_to_ssam(tpd->sdev, profile);
+ if (tp < 0)
+ return tp;
+
+ return ssam_tmp_profile_set(tpd->sdev, tp);
+}
+
+static int surface_platform_profile_probe(struct ssam_device *sdev)
+{
+ struct ssam_tmp_profile_device *tpd;
+
+ tpd = devm_kzalloc(&sdev->dev, sizeof(*tpd), GFP_KERNEL);
+ if (!tpd)
+ return -ENOMEM;
+
+ tpd->sdev = sdev;
+
+ tpd->handler.profile_get = ssam_platform_profile_get;
+ tpd->handler.profile_set = ssam_platform_profile_set;
+
+ set_bit(PLATFORM_PROFILE_LOW_POWER, tpd->handler.choices);
+ set_bit(PLATFORM_PROFILE_BALANCED, tpd->handler.choices);
+ set_bit(PLATFORM_PROFILE_BALANCED_PERFORMANCE, tpd->handler.choices);
+ set_bit(PLATFORM_PROFILE_PERFORMANCE, tpd->handler.choices);
+
+ platform_profile_register(&tpd->handler);
+ return 0;
+}
+
+static void surface_platform_profile_remove(struct ssam_device *sdev)
+{
+ platform_profile_remove();
+}
+
+static const struct ssam_device_id ssam_platform_profile_match[] = {
+ { SSAM_SDEV(TMP, 0x01, 0x00, 0x01) },
+ { },
+};
+MODULE_DEVICE_TABLE(ssam, ssam_platform_profile_match);
+
+static struct ssam_device_driver surface_platform_profile = {
+ .probe = surface_platform_profile_probe,
+ .remove = surface_platform_profile_remove,
+ .match_table = ssam_platform_profile_match,
+ .driver = {
+ .name = "surface_platform_profile",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_ssam_device_driver(surface_platform_profile);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Platform Profile Support for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
--
2.31.1
From 33f423309db2f55769a45acfd59063a8aebed1fc Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Thu, 4 Mar 2021 20:05:24 +0100
Subject: [PATCH] platform/surface: aggregator: Make SSAM_DEFINE_SYNC_REQUEST_x
define static functions
The SSAM_DEFINE_SYNC_REQUEST_x() macros are intended to reduce
boiler-plate code for SSAM request definitions by defining a wrapper
function for the specified request. The client device variants of those
macros, i.e. SSAM_DEFINE_SYNC_REQUEST_CL_x() in particular rely on the
multi-device (MD) variants, e.g.:
#define SSAM_DEFINE_SYNC_REQUEST_CL_R(name, rtype, spec...) \
SSAM_DEFINE_SYNC_REQUEST_MD_R(__raw_##name, rtype, spec) \
int name(struct ssam_device *sdev, rtype *ret) \
{ \
return __raw_##name(sdev->ctrl, sdev->uid.target, \
sdev->uid.instance, ret); \
}
This now creates the problem that it is not possible to declare the
generated functions static via
static SSAM_DEFINE_SYNC_REQUEST_CL_R(...)
as this will only apply to the function defined by the multi-device
macro, i.e. SSAM_DEFINE_SYNC_REQUEST_MD_R(). Thus compiling with
`-Wmissing-prototypes' rightfully complains that there is a 'static'
keyword missing.
To solve this, make all SSAM_DEFINE_SYNC_REQUEST_x() macros define
static functions. Non-client-device macros are also changed for
consistency. In general, we expect those functions to be only used
locally in the respective drivers for the corresponding interfaces, so
having to define a wrapper function to be able to export this should be
the odd case out.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: b78b4982d763 ("platform/surface: Add platform profile driver")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210304190524.1172197-1-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../driver-api/surface_aggregator/client.rst | 4 +-
.../platform/surface/aggregator/controller.c | 10 +--
.../surface/surface_aggregator_registry.c | 2 +-
.../surface/surface_platform_profile.c | 4 +-
include/linux/surface_aggregator/controller.h | 74 +++++++++----------
include/linux/surface_aggregator/device.h | 31 ++++----
6 files changed, 63 insertions(+), 62 deletions(-)
diff --git a/Documentation/driver-api/surface_aggregator/client.rst b/Documentation/driver-api/surface_aggregator/client.rst
index 26d13085a117..e519d374c378 100644
--- a/Documentation/driver-api/surface_aggregator/client.rst
+++ b/Documentation/driver-api/surface_aggregator/client.rst
@@ -248,7 +248,7 @@ This example defines a function
.. code-block:: c
- int __ssam_tmp_perf_mode_set(struct ssam_controller *ctrl, const __le32 *arg);
+ static int __ssam_tmp_perf_mode_set(struct ssam_controller *ctrl, const __le32 *arg);
executing the specified request, with the controller passed in when calling
said function. In this example, the argument is provided via the ``arg``
@@ -296,7 +296,7 @@ This invocation of the macro defines a function
.. code-block:: c
- int ssam_bat_get_sta(struct ssam_device *sdev, __le32 *ret);
+ static int ssam_bat_get_sta(struct ssam_device *sdev, __le32 *ret);
executing the specified request, using the device IDs and controller given
in the client device. The full list of such macros for client devices is:
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index 5bcb59ed579d..aa6f37b4f46e 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -1750,35 +1750,35 @@ EXPORT_SYMBOL_GPL(ssam_request_sync_with_buffer);
/* -- Internal SAM requests. ------------------------------------------------ */
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_get_firmware_version, __le32, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_get_firmware_version, __le32, {
.target_category = SSAM_SSH_TC_SAM,
.target_id = 0x01,
.command_id = 0x13,
.instance_id = 0x00,
});
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_display_off, u8, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_display_off, u8, {
.target_category = SSAM_SSH_TC_SAM,
.target_id = 0x01,
.command_id = 0x15,
.instance_id = 0x00,
});
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_display_on, u8, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_display_on, u8, {
.target_category = SSAM_SSH_TC_SAM,
.target_id = 0x01,
.command_id = 0x16,
.instance_id = 0x00,
});
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_d0_exit, u8, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_d0_exit, u8, {
.target_category = SSAM_SSH_TC_SAM,
.target_id = 0x01,
.command_id = 0x33,
.instance_id = 0x00,
});
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_d0_entry, u8, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_ssh_notif_d0_entry, u8, {
.target_category = SSAM_SSH_TC_SAM,
.target_id = 0x01,
.command_id = 0x34,
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index caee90d135c5..cdb4a95af3e8 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -302,7 +302,7 @@ struct ssam_base_hub {
struct ssam_event_notifier notif;
};
-static SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
.target_category = SSAM_SSH_TC_BAS,
.target_id = 0x01,
.command_id = 0x0d,
diff --git a/drivers/platform/surface/surface_platform_profile.c b/drivers/platform/surface/surface_platform_profile.c
index 0081b01a5b0f..6373d3b5eb7f 100644
--- a/drivers/platform/surface/surface_platform_profile.c
+++ b/drivers/platform/surface/surface_platform_profile.c
@@ -32,12 +32,12 @@ struct ssam_tmp_profile_device {
struct platform_profile_handler handler;
};
-static SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_profile_get, struct ssam_tmp_profile_info, {
+SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_profile_get, struct ssam_tmp_profile_info, {
.target_category = SSAM_SSH_TC_TMP,
.command_id = 0x02,
});
-static SSAM_DEFINE_SYNC_REQUEST_CL_W(__ssam_tmp_profile_set, __le32, {
+SSAM_DEFINE_SYNC_REQUEST_CL_W(__ssam_tmp_profile_set, __le32, {
.target_category = SSAM_SSH_TC_TMP,
.command_id = 0x03,
});
diff --git a/include/linux/surface_aggregator/controller.h b/include/linux/surface_aggregator/controller.h
index f4b1ba887384..0806796eabcb 100644
--- a/include/linux/surface_aggregator/controller.h
+++ b/include/linux/surface_aggregator/controller.h
@@ -344,16 +344,16 @@ struct ssam_request_spec_md {
* request has been fully completed. The required transport buffer will be
* allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl)``, returning the status of the request, which is zero on success and
- * negative on failure. The ``ctrl`` parameter is the controller via which the
- * request is being sent.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl)``, returning the status of the request, which is
+ * zero on success and negative on failure. The ``ctrl`` parameter is the
+ * controller via which the request is being sent.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_N(name, spec...) \
- int name(struct ssam_controller *ctrl) \
+ static int name(struct ssam_controller *ctrl) \
{ \
struct ssam_request_spec s = (struct ssam_request_spec)spec; \
struct ssam_request rqst; \
@@ -383,17 +383,17 @@ struct ssam_request_spec_md {
* returning once the request has been fully completed. The required transport
* buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl, const atype *arg)``, returning the status of the request, which is
- * zero on success and negative on failure. The ``ctrl`` parameter is the
- * controller via which the request is sent. The request argument is specified
- * via the ``arg`` pointer.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, const atype *arg)``, returning the status of the
+ * request, which is zero on success and negative on failure. The ``ctrl``
+ * parameter is the controller via which the request is sent. The request
+ * argument is specified via the ``arg`` pointer.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_W(name, atype, spec...) \
- int name(struct ssam_controller *ctrl, const atype *arg) \
+ static int name(struct ssam_controller *ctrl, const atype *arg) \
{ \
struct ssam_request_spec s = (struct ssam_request_spec)spec; \
struct ssam_request rqst; \
@@ -424,17 +424,17 @@ struct ssam_request_spec_md {
* request itself, returning once the request has been fully completed. The
* required transport buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl, rtype *ret)``, returning the status of the request, which is zero on
- * success and negative on failure. The ``ctrl`` parameter is the controller
- * via which the request is sent. The request's return value is written to the
- * memory pointed to by the ``ret`` parameter.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, rtype *ret)``, returning the status of the request,
+ * which is zero on success and negative on failure. The ``ctrl`` parameter is
+ * the controller via which the request is sent. The request's return value is
+ * written to the memory pointed to by the ``ret`` parameter.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_R(name, rtype, spec...) \
- int name(struct ssam_controller *ctrl, rtype *ret) \
+ static int name(struct ssam_controller *ctrl, rtype *ret) \
{ \
struct ssam_request_spec s = (struct ssam_request_spec)spec; \
struct ssam_request rqst; \
@@ -483,17 +483,17 @@ struct ssam_request_spec_md {
* returning once the request has been fully completed. The required transport
* buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl, u8 tid, u8 iid)``, returning the status of the request, which is
- * zero on success and negative on failure. The ``ctrl`` parameter is the
- * controller via which the request is sent, ``tid`` the target ID for the
- * request, and ``iid`` the instance ID.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, u8 tid, u8 iid)``, returning the status of the
+ * request, which is zero on success and negative on failure. The ``ctrl``
+ * parameter is the controller via which the request is sent, ``tid`` the
+ * target ID for the request, and ``iid`` the instance ID.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_MD_N(name, spec...) \
- int name(struct ssam_controller *ctrl, u8 tid, u8 iid) \
+ static int name(struct ssam_controller *ctrl, u8 tid, u8 iid) \
{ \
struct ssam_request_spec_md s = (struct ssam_request_spec_md)spec; \
struct ssam_request rqst; \
@@ -524,18 +524,18 @@ struct ssam_request_spec_md {
* the request itself, returning once the request has been fully completed.
* The required transport buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl, u8 tid, u8 iid, const atype *arg)``, returning the status of the
- * request, which is zero on success and negative on failure. The ``ctrl``
- * parameter is the controller via which the request is sent, ``tid`` the
- * target ID for the request, and ``iid`` the instance ID. The request argument
- * is specified via the ``arg`` pointer.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, u8 tid, u8 iid, const atype *arg)``, returning the
+ * status of the request, which is zero on success and negative on failure.
+ * The ``ctrl`` parameter is the controller via which the request is sent,
+ * ``tid`` the target ID for the request, and ``iid`` the instance ID. The
+ * request argument is specified via the ``arg`` pointer.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_MD_W(name, atype, spec...) \
- int name(struct ssam_controller *ctrl, u8 tid, u8 iid, const atype *arg)\
+ static int name(struct ssam_controller *ctrl, u8 tid, u8 iid, const atype *arg) \
{ \
struct ssam_request_spec_md s = (struct ssam_request_spec_md)spec; \
struct ssam_request rqst; \
@@ -567,18 +567,18 @@ struct ssam_request_spec_md {
* execution of the request itself, returning once the request has been fully
* completed. The required transport buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_controller
- * *ctrl, u8 tid, u8 iid, rtype *ret)``, returning the status of the request,
- * which is zero on success and negative on failure. The ``ctrl`` parameter is
- * the controller via which the request is sent, ``tid`` the target ID for the
- * request, and ``iid`` the instance ID. The request's return value is written
- * to the memory pointed to by the ``ret`` parameter.
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, u8 tid, u8 iid, rtype *ret)``, returning the status
+ * of the request, which is zero on success and negative on failure. The
+ * ``ctrl`` parameter is the controller via which the request is sent, ``tid``
+ * the target ID for the request, and ``iid`` the instance ID. The request's
+ * return value is written to the memory pointed to by the ``ret`` parameter.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_MD_R(name, rtype, spec...) \
- int name(struct ssam_controller *ctrl, u8 tid, u8 iid, rtype *ret) \
+ static int name(struct ssam_controller *ctrl, u8 tid, u8 iid, rtype *ret) \
{ \
struct ssam_request_spec_md s = (struct ssam_request_spec_md)spec; \
struct ssam_request rqst; \
diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index 02f3e06c0a60..4441ad667c3f 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -336,17 +336,18 @@ void ssam_device_driver_unregister(struct ssam_device_driver *d);
* request has been fully completed. The required transport buffer will be
* allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_device *sdev)``,
- * returning the status of the request, which is zero on success and negative
- * on failure. The ``sdev`` parameter specifies both the target device of the
- * request and by association the controller via which the request is sent.
+ * The generated function is defined as ``static int name(struct ssam_device
+ * *sdev)``, returning the status of the request, which is zero on success and
+ * negative on failure. The ``sdev`` parameter specifies both the target
+ * device of the request and by association the controller via which the
+ * request is sent.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_CL_N(name, spec...) \
SSAM_DEFINE_SYNC_REQUEST_MD_N(__raw_##name, spec) \
- int name(struct ssam_device *sdev) \
+ static int name(struct ssam_device *sdev) \
{ \
return __raw_##name(sdev->ctrl, sdev->uid.target, \
sdev->uid.instance); \
@@ -368,19 +369,19 @@ void ssam_device_driver_unregister(struct ssam_device_driver *d);
* itself, returning once the request has been fully completed. The required
* transport buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_device *sdev,
- * const atype *arg)``, returning the status of the request, which is zero on
- * success and negative on failure. The ``sdev`` parameter specifies both the
- * target device of the request and by association the controller via which
- * the request is sent. The request's argument is specified via the ``arg``
- * pointer.
+ * The generated function is defined as ``static int name(struct ssam_device
+ * *sdev, const atype *arg)``, returning the status of the request, which is
+ * zero on success and negative on failure. The ``sdev`` parameter specifies
+ * both the target device of the request and by association the controller via
+ * which the request is sent. The request's argument is specified via the
+ * ``arg`` pointer.
*
* Refer to ssam_request_sync_onstack() for more details on the behavior of
* the generated function.
*/
#define SSAM_DEFINE_SYNC_REQUEST_CL_W(name, atype, spec...) \
SSAM_DEFINE_SYNC_REQUEST_MD_W(__raw_##name, atype, spec) \
- int name(struct ssam_device *sdev, const atype *arg) \
+ static int name(struct ssam_device *sdev, const atype *arg) \
{ \
return __raw_##name(sdev->ctrl, sdev->uid.target, \
sdev->uid.instance, arg); \
@@ -402,8 +403,8 @@ void ssam_device_driver_unregister(struct ssam_device_driver *d);
* itself, returning once the request has been fully completed. The required
* transport buffer will be allocated on the stack.
*
- * The generated function is defined as ``int name(struct ssam_device *sdev,
- * rtype *ret)``, returning the status of the request, which is zero on
+ * The generated function is defined as ``static int name(struct ssam_device
+ * *sdev, rtype *ret)``, returning the status of the request, which is zero on
* success and negative on failure. The ``sdev`` parameter specifies both the
* target device of the request and by association the controller via which
* the request is sent. The request's return value is written to the memory
@@ -414,7 +415,7 @@ void ssam_device_driver_unregister(struct ssam_device_driver *d);
*/
#define SSAM_DEFINE_SYNC_REQUEST_CL_R(name, rtype, spec...) \
SSAM_DEFINE_SYNC_REQUEST_MD_R(__raw_##name, rtype, spec) \
- int name(struct ssam_device *sdev, rtype *ret) \
+ static int name(struct ssam_device *sdev, rtype *ret) \
{ \
return __raw_##name(sdev->ctrl, sdev->uid.target, \
sdev->uid.instance, ret); \
--
2.31.1
From 7a07b11680d1d98ca77a55f37c5a38711b487ca5 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Mon, 8 Mar 2021 19:48:17 +0100
Subject: [PATCH] platform/surface: Add DTX driver
The Microsoft Surface Book series devices consist of a so-called
clipboard part (containing the CPU, touchscreen, and primary battery)
and a base part (containing keyboard, secondary battery, and optional
discrete GPU). These parts can be separated, i.e. the clipboard can be
detached and used as tablet.
This detachment process is initiated by pressing a button. On the
Surface Book 2 and 3 (targeted with this commit), the Surface Aggregator
Module (i.e. the embedded controller on those devices) attempts to send
a notification to any listening client driver and waits for further
instructions (i.e. whether the detachment process should continue or be
aborted). If it does not receive a response in a certain time-frame, the
detachment process (by default) continues and the clipboard can be
physically separated. In other words, (by default and) without a driver,
the detachment process takes about 10 seconds to complete.
This commit introduces a driver for this detachment system (called DTX).
This driver allows a user-space daemon to control and influence the
detachment behavior. Specifically, it forwards any detachment requests
to user-space, allows user-space to make such requests itself, and
allows handling of those requests. Requests can be handled by either
aborting, continuing/allowing, or delaying (i.e. resetting the timeout
via a heartbeat commend). The user-space API is implemented via the
/dev/surface/dtx miscdevice.
In addition, user-space can change the default behavior on timeout from
allowing detachment to disallowing it, which is useful if the (optional)
discrete GPU is in use.
Furthermore, this driver allows user-space to receive notifications
about the state of the base, specifically when it is physically removed
(as opposed to detachment requested), in what manner it is connected
(i.e. in reverse-/tent-/studio- or laptop-mode), and what type of base
is connected. Based on this information, the driver also provides a
simple tablet-mode switch (aliasing all modes without keyboard access,
i.e. tablet-mode and studio-mode to its reported tablet-mode).
An implementation of such a user-space daemon, allowing configuration of
detachment behavior via scripts (e.g. safely unmounting USB devices
connected to the base before continuing) can be found at [1].
[1]: https://github.com/linux-surface/surface-dtx-daemon
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210308184819.437438-2-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../userspace-api/ioctl/ioctl-number.rst | 2 +
MAINTAINERS | 7 +
drivers/platform/surface/Kconfig | 16 +
drivers/platform/surface/Makefile | 1 +
drivers/platform/surface/surface_dtx.c | 1201 +++++++++++++++++
include/uapi/linux/surface_aggregator/dtx.h | 146 ++
6 files changed, 1373 insertions(+)
create mode 100644 drivers/platform/surface/surface_dtx.c
create mode 100644 include/uapi/linux/surface_aggregator/dtx.h
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 599bd4493944..1c28b8ef6677 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -327,6 +327,8 @@ Code Seq# Include File Comments
0xA4 00-1F uapi/asm/sgx.h <mailto:linux-sgx@vger.kernel.org>
0xA5 01 linux/surface_aggregator/cdev.h Microsoft Surface Platform System Aggregator
<mailto:luzmaximilian@gmail.com>
+0xA5 20-2F linux/surface_aggregator/dtx.h Microsoft Surface DTX driver
+ <mailto:luzmaximilian@gmail.com>
0xAA 00-3F linux/uapi/linux/userfaultfd.h
0xAB 00-1F linux/nbd.h
0xAC 00-1F linux/raw.h
diff --git a/MAINTAINERS b/MAINTAINERS
index fce5cdcefc0b..3917e7363520 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11868,6 +11868,13 @@ F: drivers/scsi/smartpqi/smartpqi*.[ch]
F: include/linux/cciss*.h
F: include/uapi/linux/cciss*.h
+MICROSOFT SURFACE DTX DRIVER
+M: Maximilian Luz <luzmaximilian@gmail.com>
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/platform/surface/surface_dtx.c
+F: include/uapi/linux/surface_aggregator/dtx.h
+
MICROSOFT SURFACE GPE LID SUPPORT DRIVER
M: Maximilian Luz <luzmaximilian@gmail.com>
L: platform-driver-x86@vger.kernel.org
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index 6fb304da845f..41d67bb250fd 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -111,6 +111,22 @@ config SURFACE_BOOK1_DGPU_SWITCH
This driver provides a sysfs switch to set the power-state of the
discrete GPU found on the Microsoft Surface Book 1.
+config SURFACE_DTX
+ tristate "Surface DTX (Detachment System) Driver"
+ depends on SURFACE_AGGREGATOR
+ depends on INPUT
+ help
+ Driver for the Surface Book clipboard detachment system (DTX).
+
+ On the Surface Book series devices, the display part containing the
+ CPU (called the clipboard) can be detached from the base (containing a
+ battery, the keyboard, and, optionally, a discrete GPU) by (if
+ necessary) unlocking and opening the latch connecting both parts.
+
+ This driver provides a user-space interface that can influence the
+ behavior of this process, which includes the option to abort it in
+ case the base is still in use or speed it up in case it is not.
+
config SURFACE_GPE
tristate "Surface GPE/Lid Support Driver"
depends on DMI
diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile
index f7187bae1729..0cc63440328d 100644
--- a/drivers/platform/surface/Makefile
+++ b/drivers/platform/surface/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_SURFACE_AGGREGATOR) += aggregator/
obj-$(CONFIG_SURFACE_AGGREGATOR_CDEV) += surface_aggregator_cdev.o
obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o
obj-$(CONFIG_SURFACE_BOOK1_DGPU_SWITCH) += surfacebook1_dgpu_switch.o
+obj-$(CONFIG_SURFACE_DTX) += surface_dtx.o
obj-$(CONFIG_SURFACE_GPE) += surface_gpe.o
obj-$(CONFIG_SURFACE_HOTPLUG) += surface_hotplug.o
obj-$(CONFIG_SURFACE_PLATFORM_PROFILE) += surface_platform_profile.o
diff --git a/drivers/platform/surface/surface_dtx.c b/drivers/platform/surface/surface_dtx.c
new file mode 100644
index 000000000000..1301fab0ea14
--- /dev/null
+++ b/drivers/platform/surface/surface_dtx.c
@@ -0,0 +1,1201 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface Book (gen. 2 and later) detachment system (DTX) driver.
+ *
+ * Provides a user-space interface to properly handle clipboard/tablet
+ * (containing screen and processor) detachment from the base of the device
+ * (containing the keyboard and optionally a discrete GPU). Allows to
+ * acknowledge (to speed things up), abort (e.g. in case the dGPU is still in
+ * use), or request detachment via user-space.
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/input.h>
+#include <linux/ioctl.h>
+#include <linux/kernel.h>
+#include <linux/kfifo.h>
+#include <linux/kref.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/dtx.h>
+
+
+/* -- SSAM interface. ------------------------------------------------------- */
+
+enum sam_event_cid_bas {
+ SAM_EVENT_CID_DTX_CONNECTION = 0x0c,
+ SAM_EVENT_CID_DTX_REQUEST = 0x0e,
+ SAM_EVENT_CID_DTX_CANCEL = 0x0f,
+ SAM_EVENT_CID_DTX_LATCH_STATUS = 0x11,
+};
+
+enum ssam_bas_base_state {
+ SSAM_BAS_BASE_STATE_DETACH_SUCCESS = 0x00,
+ SSAM_BAS_BASE_STATE_ATTACHED = 0x01,
+ SSAM_BAS_BASE_STATE_NOT_FEASIBLE = 0x02,
+};
+
+enum ssam_bas_latch_status {
+ SSAM_BAS_LATCH_STATUS_CLOSED = 0x00,
+ SSAM_BAS_LATCH_STATUS_OPENED = 0x01,
+ SSAM_BAS_LATCH_STATUS_FAILED_TO_OPEN = 0x02,
+ SSAM_BAS_LATCH_STATUS_FAILED_TO_REMAIN_OPEN = 0x03,
+ SSAM_BAS_LATCH_STATUS_FAILED_TO_CLOSE = 0x04,
+};
+
+enum ssam_bas_cancel_reason {
+ SSAM_BAS_CANCEL_REASON_NOT_FEASIBLE = 0x00, /* Low battery. */
+ SSAM_BAS_CANCEL_REASON_TIMEOUT = 0x02,
+ SSAM_BAS_CANCEL_REASON_FAILED_TO_OPEN = 0x03,
+ SSAM_BAS_CANCEL_REASON_FAILED_TO_REMAIN_OPEN = 0x04,
+ SSAM_BAS_CANCEL_REASON_FAILED_TO_CLOSE = 0x05,
+};
+
+struct ssam_bas_base_info {
+ u8 state;
+ u8 base_id;
+} __packed;
+
+static_assert(sizeof(struct ssam_bas_base_info) == 2);
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_lock, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x06,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_unlock, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x07,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_request, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x08,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_confirm, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x09,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_heartbeat, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x0a,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_N(ssam_bas_latch_cancel, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x0b,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_get_base, struct ssam_bas_base_info, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x0c,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_get_device_mode, u8, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x0d,
+ .instance_id = 0x00,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_get_latch_status, u8, {
+ .target_category = SSAM_SSH_TC_BAS,
+ .target_id = 0x01,
+ .command_id = 0x11,
+ .instance_id = 0x00,
+});
+
+
+/* -- Main structures. ------------------------------------------------------ */
+
+enum sdtx_device_state {
+ SDTX_DEVICE_SHUTDOWN_BIT = BIT(0),
+ SDTX_DEVICE_DIRTY_BASE_BIT = BIT(1),
+ SDTX_DEVICE_DIRTY_MODE_BIT = BIT(2),
+ SDTX_DEVICE_DIRTY_LATCH_BIT = BIT(3),
+};
+
+struct sdtx_device {
+ struct kref kref;
+ struct rw_semaphore lock; /* Guards device and controller reference. */
+
+ struct device *dev;
+ struct ssam_controller *ctrl;
+ unsigned long flags;
+
+ struct miscdevice mdev;
+ wait_queue_head_t waitq;
+ struct mutex write_lock; /* Guards order of events/notifications. */
+ struct rw_semaphore client_lock; /* Guards client list. */
+ struct list_head client_list;
+
+ struct delayed_work state_work;
+ struct {
+ struct ssam_bas_base_info base;
+ u8 device_mode;
+ u8 latch_status;
+ } state;
+
+ struct delayed_work mode_work;
+ struct input_dev *mode_switch;
+
+ struct ssam_event_notifier notif;
+};
+
+enum sdtx_client_state {
+ SDTX_CLIENT_EVENTS_ENABLED_BIT = BIT(0),
+};
+
+struct sdtx_client {
+ struct sdtx_device *ddev;
+ struct list_head node;
+ unsigned long flags;
+
+ struct fasync_struct *fasync;
+
+ struct mutex read_lock; /* Guards FIFO buffer read access. */
+ DECLARE_KFIFO(buffer, u8, 512);
+};
+
+static void __sdtx_device_release(struct kref *kref)
+{
+ struct sdtx_device *ddev = container_of(kref, struct sdtx_device, kref);
+
+ mutex_destroy(&ddev->write_lock);
+ kfree(ddev);
+}
+
+static struct sdtx_device *sdtx_device_get(struct sdtx_device *ddev)
+{
+ if (ddev)
+ kref_get(&ddev->kref);
+
+ return ddev;
+}
+
+static void sdtx_device_put(struct sdtx_device *ddev)
+{
+ if (ddev)
+ kref_put(&ddev->kref, __sdtx_device_release);
+}
+
+
+/* -- Firmware value translations. ------------------------------------------ */
+
+static u16 sdtx_translate_base_state(struct sdtx_device *ddev, u8 state)
+{
+ switch (state) {
+ case SSAM_BAS_BASE_STATE_ATTACHED:
+ return SDTX_BASE_ATTACHED;
+
+ case SSAM_BAS_BASE_STATE_DETACH_SUCCESS:
+ return SDTX_BASE_DETACHED;
+
+ case SSAM_BAS_BASE_STATE_NOT_FEASIBLE:
+ return SDTX_DETACH_NOT_FEASIBLE;
+
+ default:
+ dev_err(ddev->dev, "unknown base state: %#04x\n", state);
+ return SDTX_UNKNOWN(state);
+ }
+}
+
+static u16 sdtx_translate_latch_status(struct sdtx_device *ddev, u8 status)
+{
+ switch (status) {
+ case SSAM_BAS_LATCH_STATUS_CLOSED:
+ return SDTX_LATCH_CLOSED;
+
+ case SSAM_BAS_LATCH_STATUS_OPENED:
+ return SDTX_LATCH_OPENED;
+
+ case SSAM_BAS_LATCH_STATUS_FAILED_TO_OPEN:
+ return SDTX_ERR_FAILED_TO_OPEN;
+
+ case SSAM_BAS_LATCH_STATUS_FAILED_TO_REMAIN_OPEN:
+ return SDTX_ERR_FAILED_TO_REMAIN_OPEN;
+
+ case SSAM_BAS_LATCH_STATUS_FAILED_TO_CLOSE:
+ return SDTX_ERR_FAILED_TO_CLOSE;
+
+ default:
+ dev_err(ddev->dev, "unknown latch status: %#04x\n", status);
+ return SDTX_UNKNOWN(status);
+ }
+}
+
+static u16 sdtx_translate_cancel_reason(struct sdtx_device *ddev, u8 reason)
+{
+ switch (reason) {
+ case SSAM_BAS_CANCEL_REASON_NOT_FEASIBLE:
+ return SDTX_DETACH_NOT_FEASIBLE;
+
+ case SSAM_BAS_CANCEL_REASON_TIMEOUT:
+ return SDTX_DETACH_TIMEDOUT;
+
+ case SSAM_BAS_CANCEL_REASON_FAILED_TO_OPEN:
+ return SDTX_ERR_FAILED_TO_OPEN;
+
+ case SSAM_BAS_CANCEL_REASON_FAILED_TO_REMAIN_OPEN:
+ return SDTX_ERR_FAILED_TO_REMAIN_OPEN;
+
+ case SSAM_BAS_CANCEL_REASON_FAILED_TO_CLOSE:
+ return SDTX_ERR_FAILED_TO_CLOSE;
+
+ default:
+ dev_err(ddev->dev, "unknown cancel reason: %#04x\n", reason);
+ return SDTX_UNKNOWN(reason);
+ }
+}
+
+
+/* -- IOCTLs. --------------------------------------------------------------- */
+
+static int sdtx_ioctl_get_base_info(struct sdtx_device *ddev,
+ struct sdtx_base_info __user *buf)
+{
+ struct ssam_bas_base_info raw;
+ struct sdtx_base_info info;
+ int status;
+
+ lockdep_assert_held_read(&ddev->lock);
+
+ status = ssam_retry(ssam_bas_get_base, ddev->ctrl, &raw);
+ if (status < 0)
+ return status;
+
+ info.state = sdtx_translate_base_state(ddev, raw.state);
+ info.base_id = SDTX_BASE_TYPE_SSH(raw.base_id);
+
+ if (copy_to_user(buf, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int sdtx_ioctl_get_device_mode(struct sdtx_device *ddev, u16 __user *buf)
+{
+ u8 mode;
+ int status;
+
+ lockdep_assert_held_read(&ddev->lock);
+
+ status = ssam_retry(ssam_bas_get_device_mode, ddev->ctrl, &mode);
+ if (status < 0)
+ return status;
+
+ return put_user(mode, buf);
+}
+
+static int sdtx_ioctl_get_latch_status(struct sdtx_device *ddev, u16 __user *buf)
+{
+ u8 latch;
+ int status;
+
+ lockdep_assert_held_read(&ddev->lock);
+
+ status = ssam_retry(ssam_bas_get_latch_status, ddev->ctrl, &latch);
+ if (status < 0)
+ return status;
+
+ return put_user(sdtx_translate_latch_status(ddev, latch), buf);
+}
+
+static long __surface_dtx_ioctl(struct sdtx_client *client, unsigned int cmd, unsigned long arg)
+{
+ struct sdtx_device *ddev = client->ddev;
+
+ lockdep_assert_held_read(&ddev->lock);
+
+ switch (cmd) {
+ case SDTX_IOCTL_EVENTS_ENABLE:
+ set_bit(SDTX_CLIENT_EVENTS_ENABLED_BIT, &client->flags);
+ return 0;
+
+ case SDTX_IOCTL_EVENTS_DISABLE:
+ clear_bit(SDTX_CLIENT_EVENTS_ENABLED_BIT, &client->flags);
+ return 0;
+
+ case SDTX_IOCTL_LATCH_LOCK:
+ return ssam_retry(ssam_bas_latch_lock, ddev->ctrl);
+
+ case SDTX_IOCTL_LATCH_UNLOCK:
+ return ssam_retry(ssam_bas_latch_unlock, ddev->ctrl);
+
+ case SDTX_IOCTL_LATCH_REQUEST:
+ return ssam_retry(ssam_bas_latch_request, ddev->ctrl);
+
+ case SDTX_IOCTL_LATCH_CONFIRM:
+ return ssam_retry(ssam_bas_latch_confirm, ddev->ctrl);
+
+ case SDTX_IOCTL_LATCH_HEARTBEAT:
+ return ssam_retry(ssam_bas_latch_heartbeat, ddev->ctrl);
+
+ case SDTX_IOCTL_LATCH_CANCEL:
+ return ssam_retry(ssam_bas_latch_cancel, ddev->ctrl);
+
+ case SDTX_IOCTL_GET_BASE_INFO:
+ return sdtx_ioctl_get_base_info(ddev, (struct sdtx_base_info __user *)arg);
+
+ case SDTX_IOCTL_GET_DEVICE_MODE:
+ return sdtx_ioctl_get_device_mode(ddev, (u16 __user *)arg);
+
+ case SDTX_IOCTL_GET_LATCH_STATUS:
+ return sdtx_ioctl_get_latch_status(ddev, (u16 __user *)arg);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static long surface_dtx_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct sdtx_client *client = file->private_data;
+ long status;
+
+ if (down_read_killable(&client->ddev->lock))
+ return -ERESTARTSYS;
+
+ if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &client->ddev->flags)) {
+ up_read(&client->ddev->lock);
+ return -ENODEV;
+ }
+
+ status = __surface_dtx_ioctl(client, cmd, arg);
+
+ up_read(&client->ddev->lock);
+ return status;
+}
+
+
+/* -- File operations. ------------------------------------------------------ */
+
+static int surface_dtx_open(struct inode *inode, struct file *file)
+{
+ struct sdtx_device *ddev = container_of(file->private_data, struct sdtx_device, mdev);
+ struct sdtx_client *client;
+
+ /* Initialize client. */
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (!client)
+ return -ENOMEM;
+
+ client->ddev = sdtx_device_get(ddev);
+
+ INIT_LIST_HEAD(&client->node);
+
+ mutex_init(&client->read_lock);
+ INIT_KFIFO(client->buffer);
+
+ file->private_data = client;
+
+ /* Attach client. */
+ down_write(&ddev->client_lock);
+
+ /*
+ * Do not add a new client if the device has been shut down. Note that
+ * it's enough to hold the client_lock here as, during shutdown, we
+ * only acquire that lock and remove clients after marking the device
+ * as shut down.
+ */
+ if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &ddev->flags)) {
+ up_write(&ddev->client_lock);
+ sdtx_device_put(client->ddev);
+ kfree(client);
+ return -ENODEV;
+ }
+
+ list_add_tail(&client->node, &ddev->client_list);
+ up_write(&ddev->client_lock);
+
+ stream_open(inode, file);
+ return 0;
+}
+
+static int surface_dtx_release(struct inode *inode, struct file *file)
+{
+ struct sdtx_client *client = file->private_data;
+
+ /* Detach client. */
+ down_write(&client->ddev->client_lock);
+ list_del(&client->node);
+ up_write(&client->ddev->client_lock);
+
+ /* Free client. */
+ sdtx_device_put(client->ddev);
+ mutex_destroy(&client->read_lock);
+ kfree(client);
+
+ return 0;
+}
+
+static ssize_t surface_dtx_read(struct file *file, char __user *buf, size_t count, loff_t *offs)
+{
+ struct sdtx_client *client = file->private_data;
+ struct sdtx_device *ddev = client->ddev;
+ unsigned int copied;
+ int status = 0;
+
+ if (down_read_killable(&ddev->lock))
+ return -ERESTARTSYS;
+
+ /* Make sure we're not shut down. */
+ if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &ddev->flags)) {
+ up_read(&ddev->lock);
+ return -ENODEV;
+ }
+
+ do {
+ /* Check availability, wait if necessary. */
+ if (kfifo_is_empty(&client->buffer)) {
+ up_read(&ddev->lock);
+
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ status = wait_event_interruptible(ddev->waitq,
+ !kfifo_is_empty(&client->buffer) ||
+ test_bit(SDTX_DEVICE_SHUTDOWN_BIT,
+ &ddev->flags));
+ if (status < 0)
+ return status;
+
+ if (down_read_killable(&client->ddev->lock))
+ return -ERESTARTSYS;
+
+ /* Need to check that we're not shut down again. */
+ if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &ddev->flags)) {
+ up_read(&ddev->lock);
+ return -ENODEV;
+ }
+ }
+
+ /* Try to read from FIFO. */
+ if (mutex_lock_interruptible(&client->read_lock)) {
+ up_read(&ddev->lock);
+ return -ERESTARTSYS;
+ }
+
+ status = kfifo_to_user(&client->buffer, buf, count, &copied);
+ mutex_unlock(&client->read_lock);
+
+ if (status < 0) {
+ up_read(&ddev->lock);
+ return status;
+ }
+
+ /* We might not have gotten anything, check this here. */
+ if (copied == 0 && (file->f_flags & O_NONBLOCK)) {
+ up_read(&ddev->lock);
+ return -EAGAIN;
+ }
+ } while (copied == 0);
+
+ up_read(&ddev->lock);
+ return copied;
+}
+
+static __poll_t surface_dtx_poll(struct file *file, struct poll_table_struct *pt)
+{
+ struct sdtx_client *client = file->private_data;
+ __poll_t events = 0;
+
+ if (down_read_killable(&client->ddev->lock))
+ return -ERESTARTSYS;
+
+ if (test_bit(SDTX_DEVICE_SHUTDOWN_BIT, &client->ddev->flags)) {
+ up_read(&client->ddev->lock);
+ return EPOLLHUP | EPOLLERR;
+ }
+
+ poll_wait(file, &client->ddev->waitq, pt);
+
+ if (!kfifo_is_empty(&client->buffer))
+ events |= EPOLLIN | EPOLLRDNORM;
+
+ up_read(&client->ddev->lock);
+ return events;
+}
+
+static int surface_dtx_fasync(int fd, struct file *file, int on)
+{
+ struct sdtx_client *client = file->private_data;
+
+ return fasync_helper(fd, file, on, &client->fasync);
+}
+
+static const struct file_operations surface_dtx_fops = {
+ .owner = THIS_MODULE,
+ .open = surface_dtx_open,
+ .release = surface_dtx_release,
+ .read = surface_dtx_read,
+ .poll = surface_dtx_poll,
+ .fasync = surface_dtx_fasync,
+ .unlocked_ioctl = surface_dtx_ioctl,
+ .compat_ioctl = surface_dtx_ioctl,
+ .llseek = no_llseek,
+};
+
+
+/* -- Event handling/forwarding. -------------------------------------------- */
+
+/*
+ * The device operation mode is not immediately updated on the EC when the
+ * base has been connected, i.e. querying the device mode inside the
+ * connection event callback yields an outdated value. Thus, we can only
+ * determine the new tablet-mode switch and device mode values after some
+ * time.
+ *
+ * These delays have been chosen by experimenting. We first delay on connect
+ * events, then check and validate the device mode against the base state and
+ * if invalid delay again by the "recheck" delay.
+ */
+#define SDTX_DEVICE_MODE_DELAY_CONNECT msecs_to_jiffies(100)
+#define SDTX_DEVICE_MODE_DELAY_RECHECK msecs_to_jiffies(100)
+
+struct sdtx_status_event {
+ struct sdtx_event e;
+ __u16 v;
+} __packed;
+
+struct sdtx_base_info_event {
+ struct sdtx_event e;
+ struct sdtx_base_info v;
+} __packed;
+
+union sdtx_generic_event {
+ struct sdtx_event common;
+ struct sdtx_status_event status;
+ struct sdtx_base_info_event base;
+};
+
+static void sdtx_update_device_mode(struct sdtx_device *ddev, unsigned long delay);
+
+/* Must be executed with ddev->write_lock held. */
+static void sdtx_push_event(struct sdtx_device *ddev, struct sdtx_event *evt)
+{
+ const size_t len = sizeof(struct sdtx_event) + evt->length;
+ struct sdtx_client *client;
+
+ lockdep_assert_held(&ddev->write_lock);
+
+ down_read(&ddev->client_lock);
+ list_for_each_entry(client, &ddev->client_list, node) {
+ if (!test_bit(SDTX_CLIENT_EVENTS_ENABLED_BIT, &client->flags))
+ continue;
+
+ if (likely(kfifo_avail(&client->buffer) >= len))
+ kfifo_in(&client->buffer, (const u8 *)evt, len);
+ else
+ dev_warn(ddev->dev, "event buffer overrun\n");
+
+ kill_fasync(&client->fasync, SIGIO, POLL_IN);
+ }
+ up_read(&ddev->client_lock);
+
+ wake_up_interruptible(&ddev->waitq);
+}
+
+static u32 sdtx_notifier(struct ssam_event_notifier *nf, const struct ssam_event *in)
+{
+ struct sdtx_device *ddev = container_of(nf, struct sdtx_device, notif);
+ union sdtx_generic_event event;
+ size_t len;
+
+ /* Validate event payload length. */
+ switch (in->command_id) {
+ case SAM_EVENT_CID_DTX_CONNECTION:
+ len = 2 * sizeof(u8);
+ break;
+
+ case SAM_EVENT_CID_DTX_REQUEST:
+ len = 0;
+ break;
+
+ case SAM_EVENT_CID_DTX_CANCEL:
+ len = sizeof(u8);
+ break;
+
+ case SAM_EVENT_CID_DTX_LATCH_STATUS:
+ len = sizeof(u8);
+ break;
+
+ default:
+ return 0;
+ };
+
+ if (in->length != len) {
+ dev_err(ddev->dev,
+ "unexpected payload size for event %#04x: got %u, expected %zu\n",
+ in->command_id, in->length, len);
+ return 0;
+ }
+
+ mutex_lock(&ddev->write_lock);
+
+ /* Translate event. */
+ switch (in->command_id) {
+ case SAM_EVENT_CID_DTX_CONNECTION:
+ clear_bit(SDTX_DEVICE_DIRTY_BASE_BIT, &ddev->flags);
+
+ /* If state has not changed: do not send new event. */
+ if (ddev->state.base.state == in->data[0] &&
+ ddev->state.base.base_id == in->data[1])
+ goto out;
+
+ ddev->state.base.state = in->data[0];
+ ddev->state.base.base_id = in->data[1];
+
+ event.base.e.length = sizeof(struct sdtx_base_info);
+ event.base.e.code = SDTX_EVENT_BASE_CONNECTION;
+ event.base.v.state = sdtx_translate_base_state(ddev, in->data[0]);
+ event.base.v.base_id = SDTX_BASE_TYPE_SSH(in->data[1]);
+ break;
+
+ case SAM_EVENT_CID_DTX_REQUEST:
+ event.common.code = SDTX_EVENT_REQUEST;
+ event.common.length = 0;
+ break;
+
+ case SAM_EVENT_CID_DTX_CANCEL:
+ event.status.e.length = sizeof(u16);
+ event.status.e.code = SDTX_EVENT_CANCEL;
+ event.status.v = sdtx_translate_cancel_reason(ddev, in->data[0]);
+ break;
+
+ case SAM_EVENT_CID_DTX_LATCH_STATUS:
+ clear_bit(SDTX_DEVICE_DIRTY_LATCH_BIT, &ddev->flags);
+
+ /* If state has not changed: do not send new event. */
+ if (ddev->state.latch_status == in->data[0])
+ goto out;
+
+ ddev->state.latch_status = in->data[0];
+
+ event.status.e.length = sizeof(u16);
+ event.status.e.code = SDTX_EVENT_LATCH_STATUS;
+ event.status.v = sdtx_translate_latch_status(ddev, in->data[0]);
+ break;
+ }
+
+ sdtx_push_event(ddev, &event.common);
+
+ /* Update device mode on base connection change. */
+ if (in->command_id == SAM_EVENT_CID_DTX_CONNECTION) {
+ unsigned long delay;
+
+ delay = in->data[0] ? SDTX_DEVICE_MODE_DELAY_CONNECT : 0;
+ sdtx_update_device_mode(ddev, delay);
+ }
+
+out:
+ mutex_unlock(&ddev->write_lock);
+ return SSAM_NOTIF_HANDLED;
+}
+
+
+/* -- State update functions. ----------------------------------------------- */
+
+static bool sdtx_device_mode_invalid(u8 mode, u8 base_state)
+{
+ return ((base_state == SSAM_BAS_BASE_STATE_ATTACHED) &&
+ (mode == SDTX_DEVICE_MODE_TABLET)) ||
+ ((base_state == SSAM_BAS_BASE_STATE_DETACH_SUCCESS) &&
+ (mode != SDTX_DEVICE_MODE_TABLET));
+}
+
+static void sdtx_device_mode_workfn(struct work_struct *work)
+{
+ struct sdtx_device *ddev = container_of(work, struct sdtx_device, mode_work.work);
+ struct sdtx_status_event event;
+ struct ssam_bas_base_info base;
+ int status, tablet;
+ u8 mode;
+
+ /* Get operation mode. */
+ status = ssam_retry(ssam_bas_get_device_mode, ddev->ctrl, &mode);
+ if (status) {
+ dev_err(ddev->dev, "failed to get device mode: %d\n", status);
+ return;
+ }
+
+ /* Get base info. */
+ status = ssam_retry(ssam_bas_get_base, ddev->ctrl, &base);
+ if (status) {
+ dev_err(ddev->dev, "failed to get base info: %d\n", status);
+ return;
+ }
+
+ /*
+ * In some cases (specifically when attaching the base), the device
+ * mode isn't updated right away. Thus we check if the device mode
+ * makes sense for the given base state and try again later if it
+ * doesn't.
+ */
+ if (sdtx_device_mode_invalid(mode, base.state)) {
+ dev_dbg(ddev->dev, "device mode is invalid, trying again\n");
+ sdtx_update_device_mode(ddev, SDTX_DEVICE_MODE_DELAY_RECHECK);
+ return;
+ }
+
+ mutex_lock(&ddev->write_lock);
+ clear_bit(SDTX_DEVICE_DIRTY_MODE_BIT, &ddev->flags);
+
+ /* Avoid sending duplicate device-mode events. */
+ if (ddev->state.device_mode == mode) {
+ mutex_unlock(&ddev->write_lock);
+ return;
+ }
+
+ ddev->state.device_mode = mode;
+
+ event.e.length = sizeof(u16);
+ event.e.code = SDTX_EVENT_DEVICE_MODE;
+ event.v = mode;
+
+ sdtx_push_event(ddev, &event.e);
+
+ /* Send SW_TABLET_MODE event. */
+ tablet = mode != SDTX_DEVICE_MODE_LAPTOP;
+ input_report_switch(ddev->mode_switch, SW_TABLET_MODE, tablet);
+ input_sync(ddev->mode_switch);
+
+ mutex_unlock(&ddev->write_lock);
+}
+
+static void sdtx_update_device_mode(struct sdtx_device *ddev, unsigned long delay)
+{
+ schedule_delayed_work(&ddev->mode_work, delay);
+}
+
+/* Must be executed with ddev->write_lock held. */
+static void __sdtx_device_state_update_base(struct sdtx_device *ddev,
+ struct ssam_bas_base_info info)
+{
+ struct sdtx_base_info_event event;
+
+ lockdep_assert_held(&ddev->write_lock);
+
+ /* Prevent duplicate events. */
+ if (ddev->state.base.state == info.state &&
+ ddev->state.base.base_id == info.base_id)
+ return;
+
+ ddev->state.base = info;
+
+ event.e.length = sizeof(struct sdtx_base_info);
+ event.e.code = SDTX_EVENT_BASE_CONNECTION;
+ event.v.state = sdtx_translate_base_state(ddev, info.state);
+ event.v.base_id = SDTX_BASE_TYPE_SSH(info.base_id);
+
+ sdtx_push_event(ddev, &event.e);
+}
+
+/* Must be executed with ddev->write_lock held. */
+static void __sdtx_device_state_update_mode(struct sdtx_device *ddev, u8 mode)
+{
+ struct sdtx_status_event event;
+ int tablet;
+
+ /*
+ * Note: This function must be called after updating the base state
+ * via __sdtx_device_state_update_base(), as we rely on the updated
+ * base state value in the validity check below.
+ */
+
+ lockdep_assert_held(&ddev->write_lock);
+
+ if (sdtx_device_mode_invalid(mode, ddev->state.base.state)) {
+ dev_dbg(ddev->dev, "device mode is invalid, trying again\n");
+ sdtx_update_device_mode(ddev, SDTX_DEVICE_MODE_DELAY_RECHECK);
+ return;
+ }
+
+ /* Prevent duplicate events. */
+ if (ddev->state.device_mode == mode)
+ return;
+
+ ddev->state.device_mode = mode;
+
+ /* Send event. */
+ event.e.length = sizeof(u16);
+ event.e.code = SDTX_EVENT_DEVICE_MODE;
+ event.v = mode;
+
+ sdtx_push_event(ddev, &event.e);
+
+ /* Send SW_TABLET_MODE event. */
+ tablet = mode != SDTX_DEVICE_MODE_LAPTOP;
+ input_report_switch(ddev->mode_switch, SW_TABLET_MODE, tablet);
+ input_sync(ddev->mode_switch);
+}
+
+/* Must be executed with ddev->write_lock held. */
+static void __sdtx_device_state_update_latch(struct sdtx_device *ddev, u8 status)
+{
+ struct sdtx_status_event event;
+
+ lockdep_assert_held(&ddev->write_lock);
+
+ /* Prevent duplicate events. */
+ if (ddev->state.latch_status == status)
+ return;
+
+ ddev->state.latch_status = status;
+
+ event.e.length = sizeof(struct sdtx_base_info);
+ event.e.code = SDTX_EVENT_BASE_CONNECTION;
+ event.v = sdtx_translate_latch_status(ddev, status);
+
+ sdtx_push_event(ddev, &event.e);
+}
+
+static void sdtx_device_state_workfn(struct work_struct *work)
+{
+ struct sdtx_device *ddev = container_of(work, struct sdtx_device, state_work.work);
+ struct ssam_bas_base_info base;
+ u8 mode, latch;
+ int status;
+
+ /* Mark everything as dirty. */
+ set_bit(SDTX_DEVICE_DIRTY_BASE_BIT, &ddev->flags);
+ set_bit(SDTX_DEVICE_DIRTY_MODE_BIT, &ddev->flags);
+ set_bit(SDTX_DEVICE_DIRTY_LATCH_BIT, &ddev->flags);
+
+ /*
+ * Ensure that the state gets marked as dirty before continuing to
+ * query it. Necessary to ensure that clear_bit() calls in
+ * sdtx_notifier() and sdtx_device_mode_workfn() actually clear these
+ * bits if an event is received while updating the state here.
+ */
+ smp_mb__after_atomic();
+
+ status = ssam_retry(ssam_bas_get_base, ddev->ctrl, &base);
+ if (status) {
+ dev_err(ddev->dev, "failed to get base state: %d\n", status);
+ return;
+ }
+
+ status = ssam_retry(ssam_bas_get_device_mode, ddev->ctrl, &mode);
+ if (status) {
+ dev_err(ddev->dev, "failed to get device mode: %d\n", status);
+ return;
+ }
+
+ status = ssam_retry(ssam_bas_get_latch_status, ddev->ctrl, &latch);
+ if (status) {
+ dev_err(ddev->dev, "failed to get latch status: %d\n", status);
+ return;
+ }
+
+ mutex_lock(&ddev->write_lock);
+
+ /*
+ * If the respective dirty-bit has been cleared, an event has been
+ * received, updating this state. The queried state may thus be out of
+ * date. At this point, we can safely assume that the state provided
+ * by the event is either up to date, or we're about to receive
+ * another event updating it.
+ */
+
+ if (test_and_clear_bit(SDTX_DEVICE_DIRTY_BASE_BIT, &ddev->flags))
+ __sdtx_device_state_update_base(ddev, base);
+
+ if (test_and_clear_bit(SDTX_DEVICE_DIRTY_MODE_BIT, &ddev->flags))
+ __sdtx_device_state_update_mode(ddev, mode);
+
+ if (test_and_clear_bit(SDTX_DEVICE_DIRTY_LATCH_BIT, &ddev->flags))
+ __sdtx_device_state_update_latch(ddev, latch);
+
+ mutex_unlock(&ddev->write_lock);
+}
+
+static void sdtx_update_device_state(struct sdtx_device *ddev, unsigned long delay)
+{
+ schedule_delayed_work(&ddev->state_work, delay);
+}
+
+
+/* -- Common device initialization. ----------------------------------------- */
+
+static int sdtx_device_init(struct sdtx_device *ddev, struct device *dev,
+ struct ssam_controller *ctrl)
+{
+ int status, tablet_mode;
+
+ /* Basic initialization. */
+ kref_init(&ddev->kref);
+ init_rwsem(&ddev->lock);
+ ddev->dev = dev;
+ ddev->ctrl = ctrl;
+
+ ddev->mdev.minor = MISC_DYNAMIC_MINOR;
+ ddev->mdev.name = "surface_dtx";
+ ddev->mdev.nodename = "surface/dtx";
+ ddev->mdev.fops = &surface_dtx_fops;
+
+ ddev->notif.base.priority = 1;
+ ddev->notif.base.fn = sdtx_notifier;
+ ddev->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
+ ddev->notif.event.id.target_category = SSAM_SSH_TC_BAS;
+ ddev->notif.event.id.instance = 0;
+ ddev->notif.event.mask = SSAM_EVENT_MASK_NONE;
+ ddev->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+ init_waitqueue_head(&ddev->waitq);
+ mutex_init(&ddev->write_lock);
+ init_rwsem(&ddev->client_lock);
+ INIT_LIST_HEAD(&ddev->client_list);
+
+ INIT_DELAYED_WORK(&ddev->mode_work, sdtx_device_mode_workfn);
+ INIT_DELAYED_WORK(&ddev->state_work, sdtx_device_state_workfn);
+
+ /*
+ * Get current device state. We want to guarantee that events are only
+ * sent when state actually changes. Thus we cannot use special
+ * "uninitialized" values, as that would cause problems when manually
+ * querying the state in surface_dtx_pm_complete(). I.e. we would not
+ * be able to detect state changes there if no change event has been
+ * received between driver initialization and first device suspension.
+ *
+ * Note that we also need to do this before registering the event
+ * notifier, as that may access the state values.
+ */
+ status = ssam_retry(ssam_bas_get_base, ddev->ctrl, &ddev->state.base);
+ if (status)
+ return status;
+
+ status = ssam_retry(ssam_bas_get_device_mode, ddev->ctrl, &ddev->state.device_mode);
+ if (status)
+ return status;
+
+ status = ssam_retry(ssam_bas_get_latch_status, ddev->ctrl, &ddev->state.latch_status);
+ if (status)
+ return status;
+
+ /* Set up tablet mode switch. */
+ ddev->mode_switch = input_allocate_device();
+ if (!ddev->mode_switch)
+ return -ENOMEM;
+
+ ddev->mode_switch->name = "Microsoft Surface DTX Device Mode Switch";
+ ddev->mode_switch->phys = "ssam/01:11:01:00:00/input0";
+ ddev->mode_switch->id.bustype = BUS_HOST;
+ ddev->mode_switch->dev.parent = ddev->dev;
+
+ tablet_mode = (ddev->state.device_mode != SDTX_DEVICE_MODE_LAPTOP);
+ input_set_capability(ddev->mode_switch, EV_SW, SW_TABLET_MODE);
+ input_report_switch(ddev->mode_switch, SW_TABLET_MODE, tablet_mode);
+
+ status = input_register_device(ddev->mode_switch);
+ if (status) {
+ input_free_device(ddev->mode_switch);
+ return status;
+ }
+
+ /* Set up event notifier. */
+ status = ssam_notifier_register(ddev->ctrl, &ddev->notif);
+ if (status)
+ goto err_notif;
+
+ /* Register miscdevice. */
+ status = misc_register(&ddev->mdev);
+ if (status)
+ goto err_mdev;
+
+ /*
+ * Update device state in case it has changed between getting the
+ * initial mode and registering the event notifier.
+ */
+ sdtx_update_device_state(ddev, 0);
+ return 0;
+
+err_notif:
+ ssam_notifier_unregister(ddev->ctrl, &ddev->notif);
+ cancel_delayed_work_sync(&ddev->mode_work);
+err_mdev:
+ input_unregister_device(ddev->mode_switch);
+ return status;
+}
+
+static struct sdtx_device *sdtx_device_create(struct device *dev, struct ssam_controller *ctrl)
+{
+ struct sdtx_device *ddev;
+ int status;
+
+ ddev = kzalloc(sizeof(*ddev), GFP_KERNEL);
+ if (!ddev)
+ return ERR_PTR(-ENOMEM);
+
+ status = sdtx_device_init(ddev, dev, ctrl);
+ if (status) {
+ sdtx_device_put(ddev);
+ return ERR_PTR(status);
+ }
+
+ return ddev;
+}
+
+static void sdtx_device_destroy(struct sdtx_device *ddev)
+{
+ struct sdtx_client *client;
+
+ /*
+ * Mark device as shut-down. Prevent new clients from being added and
+ * new operations from being executed.
+ */
+ set_bit(SDTX_DEVICE_SHUTDOWN_BIT, &ddev->flags);
+
+ /* Disable notifiers, prevent new events from arriving. */
+ ssam_notifier_unregister(ddev->ctrl, &ddev->notif);
+
+ /* Stop mode_work, prevent access to mode_switch. */
+ cancel_delayed_work_sync(&ddev->mode_work);
+
+ /* Stop state_work. */
+ cancel_delayed_work_sync(&ddev->state_work);
+
+ /* With mode_work canceled, we can unregister the mode_switch. */
+ input_unregister_device(ddev->mode_switch);
+
+ /* Wake up async clients. */
+ down_write(&ddev->client_lock);
+ list_for_each_entry(client, &ddev->client_list, node) {
+ kill_fasync(&client->fasync, SIGIO, POLL_HUP);
+ }
+ up_write(&ddev->client_lock);
+
+ /* Wake up blocking clients. */
+ wake_up_interruptible(&ddev->waitq);
+
+ /*
+ * Wait for clients to finish their current operation. After this, the
+ * controller and device references are guaranteed to be no longer in
+ * use.
+ */
+ down_write(&ddev->lock);
+ ddev->dev = NULL;
+ ddev->ctrl = NULL;
+ up_write(&ddev->lock);
+
+ /* Finally remove the misc-device. */
+ misc_deregister(&ddev->mdev);
+
+ /*
+ * We're now guaranteed that sdtx_device_open() won't be called any
+ * more, so we can now drop out reference.
+ */
+ sdtx_device_put(ddev);
+}
+
+
+/* -- PM ops. --------------------------------------------------------------- */
+
+#ifdef CONFIG_PM_SLEEP
+
+static void surface_dtx_pm_complete(struct device *dev)
+{
+ struct sdtx_device *ddev = dev_get_drvdata(dev);
+
+ /*
+ * Normally, the EC will store events while suspended (i.e. in
+ * display-off state) and release them when resumed (i.e. transitioned
+ * to display-on state). During hibernation, however, the EC will be
+ * shut down and does not store events. Furthermore, events might be
+ * dropped during prolonged suspension (it is currently unknown how
+ * big this event buffer is and how it behaves on overruns).
+ *
+ * To prevent any problems, we update the device state here. We do
+ * this delayed to ensure that any events sent by the EC directly
+ * after resuming will be handled first. The delay below has been
+ * chosen (experimentally), so that there should be ample time for
+ * these events to be handled, before we check and, if necessary,
+ * update the state.
+ */
+ sdtx_update_device_state(ddev, msecs_to_jiffies(1000));
+}
+
+static const struct dev_pm_ops surface_dtx_pm_ops = {
+ .complete = surface_dtx_pm_complete,
+};
+
+#else /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops surface_dtx_pm_ops = {};
+
+#endif /* CONFIG_PM_SLEEP */
+
+
+/* -- Platform driver. ------------------------------------------------------ */
+
+static int surface_dtx_platform_probe(struct platform_device *pdev)
+{
+ struct ssam_controller *ctrl;
+ struct sdtx_device *ddev;
+
+ /* Link to EC. */
+ ctrl = ssam_client_bind(&pdev->dev);
+ if (IS_ERR(ctrl))
+ return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl);
+
+ ddev = sdtx_device_create(&pdev->dev, ctrl);
+ if (IS_ERR(ddev))
+ return PTR_ERR(ddev);
+
+ platform_set_drvdata(pdev, ddev);
+ return 0;
+}
+
+static int surface_dtx_platform_remove(struct platform_device *pdev)
+{
+ sdtx_device_destroy(platform_get_drvdata(pdev));
+ return 0;
+}
+
+static const struct acpi_device_id surface_dtx_acpi_match[] = {
+ { "MSHW0133", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, surface_dtx_acpi_match);
+
+static struct platform_driver surface_dtx_platform_driver = {
+ .probe = surface_dtx_platform_probe,
+ .remove = surface_dtx_platform_remove,
+ .driver = {
+ .name = "surface_dtx_pltf",
+ .acpi_match_table = surface_dtx_acpi_match,
+ .pm = &surface_dtx_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_platform_driver(surface_dtx_platform_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Detachment-system driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/surface_aggregator/dtx.h b/include/uapi/linux/surface_aggregator/dtx.h
new file mode 100644
index 000000000000..0833aab0d819
--- /dev/null
+++ b/include/uapi/linux/surface_aggregator/dtx.h
@@ -0,0 +1,146 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Surface DTX (clipboard detachment system driver) user-space interface.
+ *
+ * Definitions, structs, and IOCTLs for the /dev/surface/dtx misc device. This
+ * device allows user-space to control the clipboard detachment process on
+ * Surface Book series devices.
+ *
+ * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#ifndef _UAPI_LINUX_SURFACE_AGGREGATOR_DTX_H
+#define _UAPI_LINUX_SURFACE_AGGREGATOR_DTX_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/* Status/error categories */
+#define SDTX_CATEGORY_STATUS 0x0000
+#define SDTX_CATEGORY_RUNTIME_ERROR 0x1000
+#define SDTX_CATEGORY_HARDWARE_ERROR 0x2000
+#define SDTX_CATEGORY_UNKNOWN 0xf000
+
+#define SDTX_CATEGORY_MASK 0xf000
+#define SDTX_CATEGORY(value) ((value) & SDTX_CATEGORY_MASK)
+
+#define SDTX_STATUS(code) ((code) | SDTX_CATEGORY_STATUS)
+#define SDTX_ERR_RT(code) ((code) | SDTX_CATEGORY_RUNTIME_ERROR)
+#define SDTX_ERR_HW(code) ((code) | SDTX_CATEGORY_HARDWARE_ERROR)
+#define SDTX_UNKNOWN(code) ((code) | SDTX_CATEGORY_UNKNOWN)
+
+#define SDTX_SUCCESS(value) (SDTX_CATEGORY(value) == SDTX_CATEGORY_STATUS)
+
+/* Latch status values */
+#define SDTX_LATCH_CLOSED SDTX_STATUS(0x00)
+#define SDTX_LATCH_OPENED SDTX_STATUS(0x01)
+
+/* Base state values */
+#define SDTX_BASE_DETACHED SDTX_STATUS(0x00)
+#define SDTX_BASE_ATTACHED SDTX_STATUS(0x01)
+
+/* Runtime errors (non-critical) */
+#define SDTX_DETACH_NOT_FEASIBLE SDTX_ERR_RT(0x01)
+#define SDTX_DETACH_TIMEDOUT SDTX_ERR_RT(0x02)
+
+/* Hardware errors (critical) */
+#define SDTX_ERR_FAILED_TO_OPEN SDTX_ERR_HW(0x01)
+#define SDTX_ERR_FAILED_TO_REMAIN_OPEN SDTX_ERR_HW(0x02)
+#define SDTX_ERR_FAILED_TO_CLOSE SDTX_ERR_HW(0x03)
+
+/* Base types */
+#define SDTX_DEVICE_TYPE_HID 0x0100
+#define SDTX_DEVICE_TYPE_SSH 0x0200
+
+#define SDTX_DEVICE_TYPE_MASK 0x0f00
+#define SDTX_DEVICE_TYPE(value) ((value) & SDTX_DEVICE_TYPE_MASK)
+
+#define SDTX_BASE_TYPE_HID(id) ((id) | SDTX_DEVICE_TYPE_HID)
+#define SDTX_BASE_TYPE_SSH(id) ((id) | SDTX_DEVICE_TYPE_SSH)
+
+/**
+ * enum sdtx_device_mode - Mode describing how (and if) the clipboard is
+ * attached to the base of the device.
+ * @SDTX_DEVICE_MODE_TABLET: The clipboard is detached from the base and the
+ * device operates as tablet.
+ * @SDTX_DEVICE_MODE_LAPTOP: The clipboard is attached normally to the base
+ * and the device operates as laptop.
+ * @SDTX_DEVICE_MODE_STUDIO: The clipboard is attached to the base in reverse.
+ * The device operates as tablet with keyboard and
+ * touchpad deactivated, however, the base battery
+ * and, if present in the specific device model, dGPU
+ * are available to the system.
+ */
+enum sdtx_device_mode {
+ SDTX_DEVICE_MODE_TABLET = 0x00,
+ SDTX_DEVICE_MODE_LAPTOP = 0x01,
+ SDTX_DEVICE_MODE_STUDIO = 0x02,
+};
+
+/**
+ * struct sdtx_event - Event provided by reading from the DTX device file.
+ * @length: Length of the event payload, in bytes.
+ * @code: Event code, detailing what type of event this is.
+ * @data: Payload of the event, containing @length bytes.
+ *
+ * See &enum sdtx_event_code for currently valid event codes.
+ */
+struct sdtx_event {
+ __u16 length;
+ __u16 code;
+ __u8 data[];
+} __attribute__((__packed__));
+
+/**
+ * enum sdtx_event_code - Code describing the type of an event.
+ * @SDTX_EVENT_REQUEST: Detachment request event type.
+ * @SDTX_EVENT_CANCEL: Cancel detachment process event type.
+ * @SDTX_EVENT_BASE_CONNECTION: Base/clipboard connection change event type.
+ * @SDTX_EVENT_LATCH_STATUS: Latch status change event type.
+ * @SDTX_EVENT_DEVICE_MODE: Device mode change event type.
+ *
+ * Used in &struct sdtx_event to describe the type of the event. Further event
+ * codes are reserved for future use. Any event parser should be able to
+ * gracefully handle unknown events, i.e. by simply skipping them.
+ *
+ * Consult the DTX user-space interface documentation for details regarding
+ * the individual event types.
+ */
+enum sdtx_event_code {
+ SDTX_EVENT_REQUEST = 1,
+ SDTX_EVENT_CANCEL = 2,
+ SDTX_EVENT_BASE_CONNECTION = 3,
+ SDTX_EVENT_LATCH_STATUS = 4,
+ SDTX_EVENT_DEVICE_MODE = 5,
+};
+
+/**
+ * struct sdtx_base_info - Describes if and what type of base is connected.
+ * @state: The state of the connection. Valid values are %SDTX_BASE_DETACHED,
+ * %SDTX_BASE_ATTACHED, and %SDTX_DETACH_NOT_FEASIBLE (in case a base
+ * is attached but low clipboard battery prevents detachment). Other
+ * values are currently reserved.
+ * @base_id: The type of base connected. Zero if no base is connected.
+ */
+struct sdtx_base_info {
+ __u16 state;
+ __u16 base_id;
+} __attribute__((__packed__));
+
+/* IOCTLs */
+#define SDTX_IOCTL_EVENTS_ENABLE _IO(0xa5, 0x21)
+#define SDTX_IOCTL_EVENTS_DISABLE _IO(0xa5, 0x22)
+
+#define SDTX_IOCTL_LATCH_LOCK _IO(0xa5, 0x23)
+#define SDTX_IOCTL_LATCH_UNLOCK _IO(0xa5, 0x24)
+
+#define SDTX_IOCTL_LATCH_REQUEST _IO(0xa5, 0x25)
+#define SDTX_IOCTL_LATCH_CONFIRM _IO(0xa5, 0x26)
+#define SDTX_IOCTL_LATCH_HEARTBEAT _IO(0xa5, 0x27)
+#define SDTX_IOCTL_LATCH_CANCEL _IO(0xa5, 0x28)
+
+#define SDTX_IOCTL_GET_BASE_INFO _IOR(0xa5, 0x29, struct sdtx_base_info)
+#define SDTX_IOCTL_GET_DEVICE_MODE _IOR(0xa5, 0x2a, __u16)
+#define SDTX_IOCTL_GET_LATCH_STATUS _IOR(0xa5, 0x2b, __u16)
+
+#endif /* _UAPI_LINUX_SURFACE_AGGREGATOR_DTX_H */
--
2.31.1
From 3ac523ccd43bdde0b52426d255fbc50e00659605 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Mon, 8 Mar 2021 19:48:18 +0100
Subject: [PATCH] platform/surface: dtx: Add support for native SSAM devices
Add support for native SSAM devices to the DTX driver. This allows
support for the Surface Book 3, on which the DTX device is not present
in ACPI.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210308184819.437438-3-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/Kconfig | 4 ++
drivers/platform/surface/surface_dtx.c | 90 +++++++++++++++++++++++++-
2 files changed, 93 insertions(+), 1 deletion(-)
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index 41d67bb250fd..53beaedefdd1 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -127,6 +127,10 @@ config SURFACE_DTX
behavior of this process, which includes the option to abort it in
case the base is still in use or speed it up in case it is not.
+ Note that this module can be built without support for the Surface
+ Aggregator Bus (i.e. CONFIG_SURFACE_AGGREGATOR_BUS=n). In that case,
+ some devices, specifically the Surface Book 3, will not be supported.
+
config SURFACE_GPE
tristate "Surface GPE/Lid Support Driver"
depends on DMI
diff --git a/drivers/platform/surface/surface_dtx.c b/drivers/platform/surface/surface_dtx.c
index 1301fab0ea14..85451eb94d98 100644
--- a/drivers/platform/surface/surface_dtx.c
+++ b/drivers/platform/surface/surface_dtx.c
@@ -27,6 +27,7 @@
#include <linux/workqueue.h>
#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
#include <linux/surface_aggregator/dtx.h>
@@ -1194,7 +1195,94 @@ static struct platform_driver surface_dtx_platform_driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
-module_platform_driver(surface_dtx_platform_driver);
+
+
+/* -- SSAM device driver. --------------------------------------------------- */
+
+#ifdef CONFIG_SURFACE_AGGREGATOR_BUS
+
+static int surface_dtx_ssam_probe(struct ssam_device *sdev)
+{
+ struct sdtx_device *ddev;
+
+ ddev = sdtx_device_create(&sdev->dev, sdev->ctrl);
+ if (IS_ERR(ddev))
+ return PTR_ERR(ddev);
+
+ ssam_device_set_drvdata(sdev, ddev);
+ return 0;
+}
+
+static void surface_dtx_ssam_remove(struct ssam_device *sdev)
+{
+ sdtx_device_destroy(ssam_device_get_drvdata(sdev));
+}
+
+static const struct ssam_device_id surface_dtx_ssam_match[] = {
+ { SSAM_SDEV(BAS, 0x01, 0x00, 0x00) },
+ { },
+};
+MODULE_DEVICE_TABLE(ssam, surface_dtx_ssam_match);
+
+static struct ssam_device_driver surface_dtx_ssam_driver = {
+ .probe = surface_dtx_ssam_probe,
+ .remove = surface_dtx_ssam_remove,
+ .match_table = surface_dtx_ssam_match,
+ .driver = {
+ .name = "surface_dtx",
+ .pm = &surface_dtx_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+
+static int ssam_dtx_driver_register(void)
+{
+ return ssam_device_driver_register(&surface_dtx_ssam_driver);
+}
+
+static void ssam_dtx_driver_unregister(void)
+{
+ ssam_device_driver_unregister(&surface_dtx_ssam_driver);
+}
+
+#else /* CONFIG_SURFACE_AGGREGATOR_BUS */
+
+static int ssam_dtx_driver_register(void)
+{
+ return 0;
+}
+
+static void ssam_dtx_driver_unregister(void)
+{
+}
+
+#endif /* CONFIG_SURFACE_AGGREGATOR_BUS */
+
+
+/* -- Module setup. --------------------------------------------------------- */
+
+static int __init surface_dtx_init(void)
+{
+ int status;
+
+ status = ssam_dtx_driver_register();
+ if (status)
+ return status;
+
+ status = platform_driver_register(&surface_dtx_platform_driver);
+ if (status)
+ ssam_dtx_driver_unregister();
+
+ return status;
+}
+module_init(surface_dtx_init);
+
+static void __exit surface_dtx_exit(void)
+{
+ platform_driver_unregister(&surface_dtx_platform_driver);
+ ssam_dtx_driver_unregister();
+}
+module_exit(surface_dtx_exit);
MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
MODULE_DESCRIPTION("Detachment-system driver for Surface System Aggregator Module");
--
2.31.1
From d84ff64a1fa8dce47f3d60fa9ec98db43dcaaee0 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Mon, 8 Mar 2021 19:48:19 +0100
Subject: [PATCH] docs: driver-api: Add Surface DTX driver documentation
Add documentation for the user-space interface of the Surface DTX
(detachment system) driver, used on Microsoft Surface Book series
devices.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210308184819.437438-4-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface_aggregator/clients/dtx.rst | 718 ++++++++++++++++++
.../surface_aggregator/clients/index.rst | 1 +
MAINTAINERS | 1 +
3 files changed, 720 insertions(+)
create mode 100644 Documentation/driver-api/surface_aggregator/clients/dtx.rst
diff --git a/Documentation/driver-api/surface_aggregator/clients/dtx.rst b/Documentation/driver-api/surface_aggregator/clients/dtx.rst
new file mode 100644
index 000000000000..e7e7c20007f0
--- /dev/null
+++ b/Documentation/driver-api/surface_aggregator/clients/dtx.rst
@@ -0,0 +1,718 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+.. |__u16| replace:: :c:type:`__u16 <__u16>`
+.. |sdtx_event| replace:: :c:type:`struct sdtx_event <sdtx_event>`
+.. |sdtx_event_code| replace:: :c:type:`enum sdtx_event_code <sdtx_event_code>`
+.. |sdtx_base_info| replace:: :c:type:`struct sdtx_base_info <sdtx_base_info>`
+.. |sdtx_device_mode| replace:: :c:type:`struct sdtx_device_mode <sdtx_device_mode>`
+
+======================================================
+User-Space DTX (Clipboard Detachment System) Interface
+======================================================
+
+The ``surface_dtx`` driver is responsible for proper clipboard detachment
+and re-attachment handling. To this end, it provides the ``/dev/surface/dtx``
+device file, through which it can interface with a user-space daemon. This
+daemon is then ultimately responsible for determining and taking necessary
+actions, such as unmounting devices attached to the base,
+unloading/reloading the graphics-driver, user-notifications, etc.
+
+There are two basic communication principles used in this driver: Commands
+(in other parts of the documentation also referred to as requests) and
+events. Commands are sent to the EC and may have a different implications in
+different contexts. Events are sent by the EC upon some internal state
+change. Commands are always driver-initiated, whereas events are always
+initiated by the EC.
+
+.. contents::
+
+Nomenclature
+============
+
+* **Clipboard:**
+ The detachable upper part of the Surface Book, housing the screen and CPU.
+
+* **Base:**
+ The lower part of the Surface Book from which the clipboard can be
+ detached, optionally (model dependent) housing the discrete GPU (dGPU).
+
+* **Latch:**
+ The mechanism keeping the clipboard attached to the base in normal
+ operation and allowing it to be detached when requested.
+
+* **Silently ignored commands:**
+ The command is accepted by the EC as a valid command and acknowledged
+ (following the standard communication protocol), but the EC does not act
+ upon it, i.e. ignores it.e upper part of the
+
+
+Detachment Process
+==================
+
+Warning: This part of the documentation is based on reverse engineering and
+testing and thus may contain errors or be incomplete.
+
+Latch States
+------------
+
+The latch mechanism has two major states: *open* and *closed*. In the
+*closed* state (default), the clipboard is secured to the base, whereas in
+the *open* state, the clipboard can be removed by a user.
+
+The latch can additionally be locked and, correspondingly, unlocked, which
+can influence the detachment procedure. Specifically, this locking mechanism
+is intended to prevent the dGPU, positioned in the base of the device, from
+being hot-unplugged while in use. More details can be found in the
+documentation for the detachment procedure below. By default, the latch is
+unlocked.
+
+Detachment Procedure
+--------------------
+
+Note that the detachment process is governed fully by the EC. The
+``surface_dtx`` driver only relays events from the EC to user-space and
+commands from user-space to the EC, i.e. it does not influence this process.
+
+The detachment process is started with the user pressing the *detach* button
+on the base of the device or executing the ``SDTX_IOCTL_LATCH_REQUEST`` IOCTL.
+Following that:
+
+1. The EC turns on the indicator led on the detach-button, sends a
+ *detach-request* event (``SDTX_EVENT_REQUEST``), and awaits further
+ instructions/commands. In case the latch is unlocked, the led will flash
+ green. If the latch has been locked, the led will be solid red
+
+2. The event is, via the ``surface_dtx`` driver, relayed to user-space, where
+ an appropriate user-space daemon can handle it and send instructions back
+ to the EC via IOCTLs provided by this driver.
+
+3. The EC waits for instructions from user-space and acts according to them.
+ If the EC does not receive any instructions in a given period, it will
+ time out and continue as follows:
+
+ - If the latch is unlocked, the EC will open the latch and the clipboard
+ can be detached from the base. This is the exact behavior as without
+ this driver or any user-space daemon. See the ``SDTX_IOCTL_LATCH_CONFIRM``
+ description below for more details on the follow-up behavior of the EC.
+
+ - If the latch is locked, the EC will *not* open the latch, meaning the
+ clipboard cannot be detached from the base. Furthermore, the EC sends
+ an cancel event (``SDTX_EVENT_CANCEL``) detailing this with the cancel
+ reason ``SDTX_DETACH_TIMEDOUT`` (see :ref:`events` for details).
+
+Valid responses by a user-space daemon to a detachment request event are:
+
+- Execute ``SDTX_IOCTL_LATCH_REQUEST``. This will immediately abort the
+ detachment process. Furthermore, the EC will send a detach-request event,
+ similar to the user pressing the detach-button to cancel said process (see
+ below).
+
+- Execute ``SDTX_IOCTL_LATCH_CONFIRM``. This will cause the EC to open the
+ latch, after which the user can separate clipboard and base.
+
+ As this changes the latch state, a *latch-status* event
+ (``SDTX_EVENT_LATCH_STATUS``) will be sent once the latch has been opened
+ successfully. If the EC fails to open the latch, e.g. due to hardware
+ error or low battery, a latch-cancel event (``SDTX_EVENT_CANCEL``) will be
+ sent with the cancel reason indicating the specific failure.
+
+ If the latch is currently locked, the latch will automatically be
+ unlocked before it is opened.
+
+- Execute ``SDTX_IOCTL_LATCH_HEARTBEAT``. This will reset the internal timeout.
+ No other actions will be performed, i.e. the detachment process will neither
+ be completed nor canceled, and the EC will still be waiting for further
+ responses.
+
+- Execute ``SDTX_IOCTL_LATCH_CANCEL``. This will abort the detachment process,
+ similar to ``SDTX_IOCTL_LATCH_REQUEST``, described above, or the button
+ press, described below. A *generic request* event (``SDTX_EVENT_REQUEST``)
+ is send in response to this. In contrast to those, however, this command
+ does not trigger a new detachment process if none is currently in
+ progress.
+
+- Do nothing. The detachment process eventually times out as described in
+ point 3.
+
+See :ref:`ioctls` for more details on these responses.
+
+It is important to note that, if the user presses the detach button at any
+point when a detachment operation is in progress (i.e. after the EC has sent
+the initial *detach-request* event (``SDTX_EVENT_REQUEST``) and before it
+received the corresponding response concluding the process), the detachment
+process is canceled on the EC-level and an identical event is being sent.
+Thus a *detach-request* event, by itself, does not signal the start of the
+detachment process.
+
+The detachment process may further be canceled by the EC due to hardware
+failures or a low clipboard battery. This is done via a cancel event
+(``SDTX_EVENT_CANCEL``) with the corresponding cancel reason.
+
+
+User-Space Interface Documentation
+==================================
+
+Error Codes and Status Values
+-----------------------------
+
+Error and status codes are divided into different categories, which can be
+used to determine if the status code is an error, and, if it is, the
+severity and type of that error. The current categories are:
+
+.. flat-table:: Overview of Status/Error Categories.
+ :widths: 2 1 3
+ :header-rows: 1
+
+ * - Name
+ - Value
+ - Short Description
+
+ * - ``STATUS``
+ - ``0x0000``
+ - Non-error status codes.
+
+ * - ``RUNTIME_ERROR``
+ - ``0x1000``
+ - Non-critical runtime errors.
+
+ * - ``HARDWARE_ERROR``
+ - ``0x2000``
+ - Critical hardware failures.
+
+ * - ``UNKNOWN``
+ - ``0xF000``
+ - Unknown error codes.
+
+Other categories are reserved for future use. The ``SDTX_CATEGORY()`` macro
+can be used to determine the category of any status value. The
+``SDTX_SUCCESS()`` macro can be used to check if the status value is a
+success value (``SDTX_CATEGORY_STATUS``) or if it indicates a failure.
+
+Unknown status or error codes sent by the EC are assigned to the ``UNKNOWN``
+category by the driver and may be implemented via their own code in the
+future.
+
+Currently used error codes are:
+
+.. flat-table:: Overview of Error Codes.
+ :widths: 2 1 1 3
+ :header-rows: 1
+
+ * - Name
+ - Category
+ - Value
+ - Short Description
+
+ * - ``SDTX_DETACH_NOT_FEASIBLE``
+ - ``RUNTIME``
+ - ``0x1001``
+ - Detachment not feasible due to low clipboard battery.
+
+ * - ``SDTX_DETACH_TIMEDOUT``
+ - ``RUNTIME``
+ - ``0x1002``
+ - Detachment process timed out while the latch was locked.
+
+ * - ``SDTX_ERR_FAILED_TO_OPEN``
+ - ``HARDWARE``
+ - ``0x2001``
+ - Failed to open latch.
+
+ * - ``SDTX_ERR_FAILED_TO_REMAIN_OPEN``
+ - ``HARDWARE``
+ - ``0x2002``
+ - Failed to keep latch open.
+
+ * - ``SDTX_ERR_FAILED_TO_CLOSE``
+ - ``HARDWARE``
+ - ``0x2003``
+ - Failed to close latch.
+
+Other error codes are reserved for future use. Non-error status codes may
+overlap and are generally only unique within their use-case:
+
+.. flat-table:: Latch Status Codes.
+ :widths: 2 1 1 3
+ :header-rows: 1
+
+ * - Name
+ - Category
+ - Value
+ - Short Description
+
+ * - ``SDTX_LATCH_CLOSED``
+ - ``STATUS``
+ - ``0x0000``
+ - Latch is closed/has been closed.
+
+ * - ``SDTX_LATCH_OPENED``
+ - ``STATUS``
+ - ``0x0001``
+ - Latch is open/has been opened.
+
+.. flat-table:: Base State Codes.
+ :widths: 2 1 1 3
+ :header-rows: 1
+
+ * - Name
+ - Category
+ - Value
+ - Short Description
+
+ * - ``SDTX_BASE_DETACHED``
+ - ``STATUS``
+ - ``0x0000``
+ - Base has been detached/is not present.
+
+ * - ``SDTX_BASE_ATTACHED``
+ - ``STATUS``
+ - ``0x0001``
+ - Base has been attached/is present.
+
+Again, other codes are reserved for future use.
+
+.. _events:
+
+Events
+------
+
+Events can be received by reading from the device file. They are disabled by
+default and have to be enabled by executing ``SDTX_IOCTL_EVENTS_ENABLE``
+first. All events follow the layout prescribed by |sdtx_event|. Specific
+event types can be identified by their event code, described in
+|sdtx_event_code|. Note that other event codes are reserved for future use,
+thus an event parser must be able to handle any unknown/unsupported event
+types gracefully, by relying on the payload length given in the event header.
+
+Currently provided event types are:
+
+.. flat-table:: Overview of DTX events.
+ :widths: 2 1 1 3
+ :header-rows: 1
+
+ * - Name
+ - Code
+ - Payload
+ - Short Description
+
+ * - ``SDTX_EVENT_REQUEST``
+ - ``1``
+ - ``0`` bytes
+ - Detachment process initiated/aborted.
+
+ * - ``SDTX_EVENT_CANCEL``
+ - ``2``
+ - ``2`` bytes
+ - EC canceled detachment process.
+
+ * - ``SDTX_EVENT_BASE_CONNECTION``
+ - ``3``
+ - ``4`` bytes
+ - Base connection state changed.
+
+ * - ``SDTX_EVENT_LATCH_STATUS``
+ - ``4``
+ - ``2`` bytes
+ - Latch status changed.
+
+ * - ``SDTX_EVENT_DEVICE_MODE``
+ - ``5``
+ - ``2`` bytes
+ - Device mode changed.
+
+Individual events in more detail:
+
+``SDTX_EVENT_REQUEST``
+^^^^^^^^^^^^^^^^^^^^^^
+
+Sent when a detachment process is started or, if in progress, aborted by the
+user, either via a detach button press or a detach request
+(``SDTX_IOCTL_LATCH_REQUEST``) being sent from user-space.
+
+Does not have any payload.
+
+``SDTX_EVENT_CANCEL``
+^^^^^^^^^^^^^^^^^^^^^
+
+Sent when a detachment process is canceled by the EC due to unfulfilled
+preconditions (e.g. clipboard battery too low to detach) or hardware
+failure. The reason for cancellation is given in the event payload detailed
+below and can be one of
+
+* ``SDTX_DETACH_TIMEDOUT``: Detachment timed out while the latch was locked.
+ The latch has neither been opened nor unlocked.
+
+* ``SDTX_DETACH_NOT_FEASIBLE``: Detachment not feasible due to low clipboard
+ battery.
+
+* ``SDTX_ERR_FAILED_TO_OPEN``: Could not open the latch (hardware failure).
+
+* ``SDTX_ERR_FAILED_TO_REMAIN_OPEN``: Could not keep the latch open (hardware
+ failure).
+
+* ``SDTX_ERR_FAILED_TO_CLOSE``: Could not close the latch (hardware failure).
+
+Other error codes in this context are reserved for future use.
+
+These codes can be classified via the ``SDTX_CATEGORY()`` macro to discern
+between critical hardware errors (``SDTX_CATEGORY_HARDWARE_ERROR``) or
+runtime errors (``SDTX_CATEGORY_RUNTIME_ERROR``), the latter of which may
+happen during normal operation if certain preconditions for detachment are
+not given.
+
+.. flat-table:: Detachment Cancel Event Payload
+ :widths: 1 1 4
+ :header-rows: 1
+
+ * - Field
+ - Type
+ - Description
+
+ * - ``reason``
+ - |__u16|
+ - Reason for cancellation.
+
+``SDTX_EVENT_BASE_CONNECTION``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sent when the base connection state has changed, i.e. when the base has been
+attached, detached, or detachment has become infeasible due to low clipboard
+battery. The new state and, if a base is connected, ID of the base is
+provided as payload of type |sdtx_base_info| with its layout presented
+below:
+
+.. flat-table:: Base-Connection-Change Event Payload
+ :widths: 1 1 4
+ :header-rows: 1
+
+ * - Field
+ - Type
+ - Description
+
+ * - ``state``
+ - |__u16|
+ - Base connection state.
+
+ * - ``base_id``
+ - |__u16|
+ - Type of base connected (zero if none).
+
+Possible values for ``state`` are:
+
+* ``SDTX_BASE_DETACHED``,
+* ``SDTX_BASE_ATTACHED``, and
+* ``SDTX_DETACH_NOT_FEASIBLE``.
+
+Other values are reserved for future use.
+
+``SDTX_EVENT_LATCH_STATUS``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sent when the latch status has changed, i.e. when the latch has been opened,
+closed, or an error occurred. The current status is provided as payload:
+
+.. flat-table:: Latch-Status-Change Event Payload
+ :widths: 1 1 4
+ :header-rows: 1
+
+ * - Field
+ - Type
+ - Description
+
+ * - ``status``
+ - |__u16|
+ - Latch status.
+
+Possible values for ``status`` are:
+
+* ``SDTX_LATCH_CLOSED``,
+* ``SDTX_LATCH_OPENED``,
+* ``SDTX_ERR_FAILED_TO_OPEN``,
+* ``SDTX_ERR_FAILED_TO_REMAIN_OPEN``, and
+* ``SDTX_ERR_FAILED_TO_CLOSE``.
+
+Other values are reserved for future use.
+
+``SDTX_EVENT_DEVICE_MODE``
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sent when the device mode has changed. The new device mode is provided as
+payload:
+
+.. flat-table:: Device-Mode-Change Event Payload
+ :widths: 1 1 4
+ :header-rows: 1
+
+ * - Field
+ - Type
+ - Description
+
+ * - ``mode``
+ - |__u16|
+ - Device operation mode.
+
+Possible values for ``mode`` are:
+
+* ``SDTX_DEVICE_MODE_TABLET``,
+* ``SDTX_DEVICE_MODE_LAPTOP``, and
+* ``SDTX_DEVICE_MODE_STUDIO``.
+
+Other values are reserved for future use.
+
+.. _ioctls:
+
+IOCTLs
+------
+
+The following IOCTLs are provided:
+
+.. flat-table:: Overview of DTX IOCTLs
+ :widths: 1 1 1 1 4
+ :header-rows: 1
+
+ * - Type
+ - Number
+ - Direction
+ - Name
+ - Description
+
+ * - ``0xA5``
+ - ``0x21``
+ - ``-``
+ - ``EVENTS_ENABLE``
+ - Enable events for the current file descriptor.
+
+ * - ``0xA5``
+ - ``0x22``
+ - ``-``
+ - ``EVENTS_DISABLE``
+ - Disable events for the current file descriptor.
+
+ * - ``0xA5``
+ - ``0x23``
+ - ``-``
+ - ``LATCH_LOCK``
+ - Lock the latch.
+
+ * - ``0xA5``
+ - ``0x24``
+ - ``-``
+ - ``LATCH_UNLOCK``
+ - Unlock the latch.
+
+ * - ``0xA5``
+ - ``0x25``
+ - ``-``
+ - ``LATCH_REQUEST``
+ - Request clipboard detachment.
+
+ * - ``0xA5``
+ - ``0x26``
+ - ``-``
+ - ``LATCH_CONFIRM``
+ - Confirm clipboard detachment request.
+
+ * - ``0xA5``
+ - ``0x27``
+ - ``-``
+ - ``LATCH_HEARTBEAT``
+ - Send heartbeat signal to EC.
+
+ * - ``0xA5``
+ - ``0x28``
+ - ``-``
+ - ``LATCH_CANCEL``
+ - Cancel detachment process.
+
+ * - ``0xA5``
+ - ``0x29``
+ - ``R``
+ - ``GET_BASE_INFO``
+ - Get current base/connection information.
+
+ * - ``0xA5``
+ - ``0x2A``
+ - ``R``
+ - ``GET_DEVICE_MODE``
+ - Get current device operation mode.
+
+ * - ``0xA5``
+ - ``0x2B``
+ - ``R``
+ - ``GET_LATCH_STATUS``
+ - Get current device latch status.
+
+``SDTX_IOCTL_EVENTS_ENABLE``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x22)``.
+
+Enable events for the current file descriptor. Events can be obtained by
+reading from the device, if enabled. Events are disabled by default.
+
+``SDTX_IOCTL_EVENTS_DISABLE``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x22)``.
+
+Disable events for the current file descriptor. Events can be obtained by
+reading from the device, if enabled. Events are disabled by default.
+
+``SDTX_IOCTL_LATCH_LOCK``
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x23)``.
+
+Locks the latch, causing the detachment procedure to abort without opening
+the latch on timeout. The latch is unlocked by default. This command will be
+silently ignored if the latch is already locked.
+
+``SDTX_IOCTL_LATCH_UNLOCK``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x24)``.
+
+Unlocks the latch, causing the detachment procedure to open the latch on
+timeout. The latch is unlocked by default. This command will not open the
+latch when sent during an ongoing detachment process. It will be silently
+ignored if the latch is already unlocked.
+
+``SDTX_IOCTL_LATCH_REQUEST``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x25)``.
+
+Generic latch request. Behavior depends on the context: If no
+detachment-process is active, detachment is requested. Otherwise the
+currently active detachment-process will be aborted.
+
+If a detachment process is canceled by this operation, a generic detachment
+request event (``SDTX_EVENT_REQUEST``) will be sent.
+
+This essentially behaves the same as a detachment button press.
+
+``SDTX_IOCTL_LATCH_CONFIRM``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x26)``.
+
+Acknowledges and confirms a latch request. If sent during an ongoing
+detachment process, this command causes the latch to be opened immediately.
+The latch will also be opened if it has been locked. In this case, the latch
+lock is reset to the unlocked state.
+
+This command will be silently ignored if there is currently no detachment
+procedure in progress.
+
+``SDTX_IOCTL_LATCH_HEARTBEAT``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x27)``.
+
+Sends a heartbeat, essentially resetting the detachment timeout. This
+command can be used to keep the detachment process alive while work required
+for the detachment to succeed is still in progress.
+
+This command will be silently ignored if there is currently no detachment
+procedure in progress.
+
+``SDTX_IOCTL_LATCH_CANCEL``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IO(0xA5, 0x28)``.
+
+Cancels detachment in progress (if any). If a detachment process is canceled
+by this operation, a generic detachment request event
+(``SDTX_EVENT_REQUEST``) will be sent.
+
+This command will be silently ignored if there is currently no detachment
+procedure in progress.
+
+``SDTX_IOCTL_GET_BASE_INFO``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IOR(0xA5, 0x29, struct sdtx_base_info)``.
+
+Get the current base connection state (i.e. attached/detached) and the type
+of the base connected to the clipboard. This is command essentially provides
+a way to query the information provided by the base connection change event
+(``SDTX_EVENT_BASE_CONNECTION``).
+
+Possible values for ``struct sdtx_base_info.state`` are:
+
+* ``SDTX_BASE_DETACHED``,
+* ``SDTX_BASE_ATTACHED``, and
+* ``SDTX_DETACH_NOT_FEASIBLE``.
+
+Other values are reserved for future use.
+
+``SDTX_IOCTL_GET_DEVICE_MODE``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IOR(0xA5, 0x2A, __u16)``.
+
+Returns the device operation mode, indicating if and how the base is
+attached to the clipboard. This is command essentially provides a way to
+query the information provided by the device mode change event
+(``SDTX_EVENT_DEVICE_MODE``).
+
+Returned values are:
+
+* ``SDTX_DEVICE_MODE_LAPTOP``
+* ``SDTX_DEVICE_MODE_TABLET``
+* ``SDTX_DEVICE_MODE_STUDIO``
+
+See |sdtx_device_mode| for details. Other values are reserved for future
+use.
+
+
+``SDTX_IOCTL_GET_LATCH_STATUS``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Defined as ``_IOR(0xA5, 0x2B, __u16)``.
+
+Get the current latch status or (presumably) the last error encountered when
+trying to open/close the latch. This is command essentially provides a way
+to query the information provided by the latch status change event
+(``SDTX_EVENT_LATCH_STATUS``).
+
+Returned values are:
+
+* ``SDTX_LATCH_CLOSED``,
+* ``SDTX_LATCH_OPENED``,
+* ``SDTX_ERR_FAILED_TO_OPEN``,
+* ``SDTX_ERR_FAILED_TO_REMAIN_OPEN``, and
+* ``SDTX_ERR_FAILED_TO_CLOSE``.
+
+Other values are reserved for future use.
+
+A Note on Base IDs
+------------------
+
+Base types/IDs provided via ``SDTX_EVENT_BASE_CONNECTION`` or
+``SDTX_IOCTL_GET_BASE_INFO`` are directly forwarded from the EC in the lower
+byte of the combined |__u16| value, with the driver storing the EC type from
+which this ID comes in the high byte (without this, base IDs over different
+types of ECs may be overlapping).
+
+The ``SDTX_DEVICE_TYPE()`` macro can be used to determine the EC device
+type. This can be one of
+
+* ``SDTX_DEVICE_TYPE_HID``, for Surface Aggregator Module over HID, and
+
+* ``SDTX_DEVICE_TYPE_SSH``, for Surface Aggregator Module over Surface Serial
+ Hub.
+
+Note that currently only the ``SSH`` type EC is supported, however ``HID``
+type is reserved for future use.
+
+Structures and Enums
+--------------------
+
+.. kernel-doc:: include/uapi/linux/surface_aggregator/dtx.h
+
+API Users
+=========
+
+A user-space daemon utilizing this API can be found at
+https://github.com/linux-surface/surface-dtx-daemon.
diff --git a/Documentation/driver-api/surface_aggregator/clients/index.rst b/Documentation/driver-api/surface_aggregator/clients/index.rst
index 3ccabce23271..98ea9946b8a2 100644
--- a/Documentation/driver-api/surface_aggregator/clients/index.rst
+++ b/Documentation/driver-api/surface_aggregator/clients/index.rst
@@ -11,6 +11,7 @@ This is the documentation for client drivers themselves. Refer to
:maxdepth: 1
cdev
+ dtx
san
.. only:: subproject and html
diff --git a/MAINTAINERS b/MAINTAINERS
index 3917e7363520..da1487d672a8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11872,6 +11872,7 @@ MICROSOFT SURFACE DTX DRIVER
M: Maximilian Luz <luzmaximilian@gmail.com>
L: platform-driver-x86@vger.kernel.org
S: Maintained
+F: Documentation/driver-api/surface_aggregator/clients/dtx.rst
F: drivers/platform/surface/surface_dtx.c
F: include/uapi/linux/surface_aggregator/dtx.h
--
2.31.1
From 1518f129b5389792afb8a311a11294668a5bf6e7 Mon Sep 17 00:00:00 2001
From: Wei Yongjun <weiyongjun1@huawei.com>
Date: Tue, 9 Mar 2021 13:15:00 +0000
Subject: [PATCH] platform/surface: aggregator_registry: Make symbol
'ssam_base_hub_group' static
The sparse tool complains as follows:
drivers/platform/surface/surface_aggregator_registry.c:355:30: warning:
symbol 'ssam_base_hub_group' was not declared. Should it be static?
This symbol is not used outside of surface_aggregator_registry.c, so this
commit marks it static.
Fixes: 797e78564634 ("platform/surface: aggregator_registry: Add base device hub")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210309131500.1885772-1-weiyongjun1@huawei.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/surface_aggregator_registry.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index cdb4a95af3e8..86cff5fce3cd 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -352,7 +352,7 @@ static struct attribute *ssam_base_hub_attrs[] = {
NULL,
};
-const struct attribute_group ssam_base_hub_group = {
+static const struct attribute_group ssam_base_hub_group = {
.attrs = ssam_base_hub_attrs,
};
--
2.31.1
From cec31a9cad519c94fc89a33d9170629a2d310e52 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 9 Mar 2021 17:25:50 +0100
Subject: [PATCH] platform/surface: aggregator_registry: Add support for
Surface Pro 7+
The Surface Pro 7+ is essentially a refresh of the Surface Pro 7 with
updated hardware and a new WSID identifier.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210309162550.302161-1-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/surface_aggregator_registry.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 86cff5fce3cd..eccb9d1007cd 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -191,7 +191,7 @@ static const struct software_node *ssam_node_group_sp6[] = {
NULL,
};
-/* Devices for Surface Pro 7. */
+/* Devices for Surface Pro 7 and Surface Pro 7+. */
static const struct software_node *ssam_node_group_sp7[] = {
&ssam_node_root,
&ssam_node_bat_ac,
@@ -521,6 +521,9 @@ static const struct acpi_device_id ssam_platform_hub_match[] = {
/* Surface Pro 7 */
{ "MSHW0116", (unsigned long)ssam_node_group_sp7 },
+ /* Surface Pro 7+ */
+ { "MSHW0119", (unsigned long)ssam_node_group_sp7 },
+
/* Surface Book 2 */
{ "MSHW0107", (unsigned long)ssam_node_group_sb2 },
--
2.31.1
From 891b8f70fb304ab1ff3482d5aa929ea156996ff4 Mon Sep 17 00:00:00 2001
From: kernel test robot <lkp@intel.com>
Date: Fri, 19 Mar 2021 13:19:19 +0800
Subject: [PATCH] platform/surface: fix semicolon.cocci warnings
drivers/platform/surface/surface_dtx.c:651:2-3: Unneeded semicolon
Remove unneeded semicolon.
Generated by: scripts/coccinelle/misc/semicolon.cocci
Fixes: 1d609992832e ("platform/surface: Add DTX driver")
CC: Maximilian Luz <luzmaximilian@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210319051919.GA39801@ae4f36e4f012
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/surface_dtx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/surface/surface_dtx.c b/drivers/platform/surface/surface_dtx.c
index 85451eb94d98..1fedacf74050 100644
--- a/drivers/platform/surface/surface_dtx.c
+++ b/drivers/platform/surface/surface_dtx.c
@@ -649,7 +649,7 @@ static u32 sdtx_notifier(struct ssam_event_notifier *nf, const struct ssam_event
default:
return 0;
- };
+ }
if (in->length != len) {
dev_err(ddev->dev,
--
2.31.1
From 0cd4b642ccb520ba5b9cac246da1ca2bb76216d7 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Fri, 26 Mar 2021 15:28:48 +0300
Subject: [PATCH] platform/surface: clean up a variable in surface_dtx_read()
The "&client->ddev->lock" and "&ddev->lock" are the same thing. Let's
use "&ddev->lock" consistently.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/YF3TgCcpcCYl3a//@mwanda
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/surface_dtx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/surface/surface_dtx.c b/drivers/platform/surface/surface_dtx.c
index 1fedacf74050..63ce587e79e3 100644
--- a/drivers/platform/surface/surface_dtx.c
+++ b/drivers/platform/surface/surface_dtx.c
@@ -487,7 +487,7 @@ static ssize_t surface_dtx_read(struct file *file, char __user *buf, size_t coun
if (status < 0)
return status;
- if (down_read_killable(&client->ddev->lock))
+ if (down_read_killable(&ddev->lock))
return -ERESTARTSYS;
/* Need to check that we're not shut down again. */
--
2.31.1
From 81d6d2613cf852a1129960879d0ce6b7dae67755 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 6 Apr 2021 01:12:22 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Give devices time to
set up when connecting
Sometimes, the "base connected" event that we rely on to (re-)attach the
device connected to the base is sent a bit too early. When this happens,
some devices may not be completely ready yet.
Specifically, the battery has been observed to report zero-values for
things like full charge capacity, which, however, is only loaded once
when the driver for that device probes. This can thus result in battery
readings being unavailable.
As we cannot easily and reliably discern between devices that are not
ready yet and devices that are not connected (i.e. will never be ready),
delay adding these devices. This should give them enough time to set up.
The delay is set to 2.5 seconds, which should give us a good safety
margin based on testing and still be fairly responsive for users.
To achieve that delay switch to updating via a delayed work struct,
which means that we can also get rid of some locking.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210405231222.358113-1-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
.../surface/surface_aggregator_registry.c | 98 ++++++++-----------
1 file changed, 40 insertions(+), 58 deletions(-)
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index eccb9d1007cd..685d37a7add1 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -13,10 +13,10 @@
#include <linux/kernel.h>
#include <linux/limits.h>
#include <linux/module.h>
-#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/types.h>
+#include <linux/workqueue.h>
#include <linux/surface_aggregator/controller.h>
#include <linux/surface_aggregator/device.h>
@@ -287,6 +287,13 @@ static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *c
/* -- SSAM base-hub driver. ------------------------------------------------- */
+/*
+ * Some devices (especially battery) may need a bit of time to be fully usable
+ * after being (re-)connected. This delay has been determined via
+ * experimentation.
+ */
+#define SSAM_BASE_UPDATE_CONNECT_DELAY msecs_to_jiffies(2500)
+
enum ssam_base_hub_state {
SSAM_BASE_HUB_UNINITIALIZED,
SSAM_BASE_HUB_CONNECTED,
@@ -296,8 +303,8 @@ enum ssam_base_hub_state {
struct ssam_base_hub {
struct ssam_device *sdev;
- struct mutex lock; /* Guards state update checks and transitions. */
enum ssam_base_hub_state state;
+ struct delayed_work update_work;
struct ssam_event_notifier notif;
};
@@ -335,11 +342,7 @@ static ssize_t ssam_base_hub_state_show(struct device *dev, struct device_attrib
char *buf)
{
struct ssam_base_hub *hub = dev_get_drvdata(dev);
- bool connected;
-
- mutex_lock(&hub->lock);
- connected = hub->state == SSAM_BASE_HUB_CONNECTED;
- mutex_unlock(&hub->lock);
+ bool connected = hub->state == SSAM_BASE_HUB_CONNECTED;
return sysfs_emit(buf, "%d\n", connected);
}
@@ -356,16 +359,20 @@ static const struct attribute_group ssam_base_hub_group = {
.attrs = ssam_base_hub_attrs,
};
-static int __ssam_base_hub_update(struct ssam_base_hub *hub, enum ssam_base_hub_state new)
+static void ssam_base_hub_update_workfn(struct work_struct *work)
{
+ struct ssam_base_hub *hub = container_of(work, struct ssam_base_hub, update_work.work);
struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
+ enum ssam_base_hub_state state;
int status = 0;
- lockdep_assert_held(&hub->lock);
+ status = ssam_base_hub_query_state(hub, &state);
+ if (status)
+ return;
- if (hub->state == new)
- return 0;
- hub->state = new;
+ if (hub->state == state)
+ return;
+ hub->state = state;
if (hub->state == SSAM_BASE_HUB_CONNECTED)
status = ssam_hub_add_devices(&hub->sdev->dev, hub->sdev->ctrl, node);
@@ -374,51 +381,28 @@ static int __ssam_base_hub_update(struct ssam_base_hub *hub, enum ssam_base_hub_
if (status)
dev_err(&hub->sdev->dev, "failed to update base-hub devices: %d\n", status);
-
- return status;
-}
-
-static int ssam_base_hub_update(struct ssam_base_hub *hub)
-{
- enum ssam_base_hub_state state;
- int status;
-
- mutex_lock(&hub->lock);
-
- status = ssam_base_hub_query_state(hub, &state);
- if (!status)
- status = __ssam_base_hub_update(hub, state);
-
- mutex_unlock(&hub->lock);
- return status;
}
static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
{
- struct ssam_base_hub *hub;
- struct ssam_device *sdev;
- enum ssam_base_hub_state new;
-
- hub = container_of(nf, struct ssam_base_hub, notif);
- sdev = hub->sdev;
+ struct ssam_base_hub *hub = container_of(nf, struct ssam_base_hub, notif);
+ unsigned long delay;
if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
return 0;
if (event->length < 1) {
- dev_err(&sdev->dev, "unexpected payload size: %u\n",
- event->length);
+ dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
return 0;
}
- if (event->data[0])
- new = SSAM_BASE_HUB_CONNECTED;
- else
- new = SSAM_BASE_HUB_DISCONNECTED;
+ /*
+ * Delay update when the base is being connected to give devices/EC
+ * some time to set up.
+ */
+ delay = event->data[0] ? SSAM_BASE_UPDATE_CONNECT_DELAY : 0;
- mutex_lock(&hub->lock);
- __ssam_base_hub_update(hub, new);
- mutex_unlock(&hub->lock);
+ schedule_delayed_work(&hub->update_work, delay);
/*
* Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
@@ -430,7 +414,10 @@ static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam
static int __maybe_unused ssam_base_hub_resume(struct device *dev)
{
- return ssam_base_hub_update(dev_get_drvdata(dev));
+ struct ssam_base_hub *hub = dev_get_drvdata(dev);
+
+ schedule_delayed_work(&hub->update_work, 0);
+ return 0;
}
static SIMPLE_DEV_PM_OPS(ssam_base_hub_pm_ops, NULL, ssam_base_hub_resume);
@@ -443,8 +430,6 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
if (!hub)
return -ENOMEM;
- mutex_init(&hub->lock);
-
hub->sdev = sdev;
hub->state = SSAM_BASE_HUB_UNINITIALIZED;
@@ -456,27 +441,25 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
hub->notif.event.mask = SSAM_EVENT_MASK_NONE;
hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
+ INIT_DELAYED_WORK(&hub->update_work, ssam_base_hub_update_workfn);
+
ssam_device_set_drvdata(sdev, hub);
status = ssam_notifier_register(sdev->ctrl, &hub->notif);
if (status)
- goto err_register;
-
- status = ssam_base_hub_update(hub);
- if (status)
- goto err_update;
+ return status;
status = sysfs_create_group(&sdev->dev.kobj, &ssam_base_hub_group);
if (status)
- goto err_update;
+ goto err;
+ schedule_delayed_work(&hub->update_work, 0);
return 0;
-err_update:
+err:
ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+ cancel_delayed_work_sync(&hub->update_work);
ssam_hub_remove_devices(&sdev->dev);
-err_register:
- mutex_destroy(&hub->lock);
return status;
}
@@ -487,9 +470,8 @@ static void ssam_base_hub_remove(struct ssam_device *sdev)
sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group);
ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+ cancel_delayed_work_sync(&hub->update_work);
ssam_hub_remove_devices(&sdev->dev);
-
- mutex_destroy(&hub->lock);
}
static const struct ssam_device_id ssam_base_hub_match[] = {
--
2.31.1
From 5177fd376432e132488109743f095ec3c47eafae Mon Sep 17 00:00:00 2001
From: Barry Song <song.bao.hua@hisilicon.com>
Date: Wed, 3 Mar 2021 11:49:15 +1300
Subject: [PATCH] genirq: Add IRQF_NO_AUTOEN for request_irq/nmi()
Many drivers don't want interrupts enabled automatically via request_irq().
So they are handling this issue by either way of the below two:
(1)
irq_set_status_flags(irq, IRQ_NOAUTOEN);
request_irq(dev, irq...);
(2)
request_irq(dev, irq...);
disable_irq(irq);
The code in the second way is silly and unsafe. In the small time gap
between request_irq() and disable_irq(), interrupts can still come.
The code in the first way is safe though it's subobtimal.
Add a new IRQF_NO_AUTOEN flag which can be handed in by drivers to
request_irq() and request_nmi(). It prevents the automatic enabling of the
requested interrupt/nmi in the same safe way as #1 above. With that the
various usage sites of #1 and #2 above can be simplified and corrected.
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: dmitry.torokhov@gmail.com
Link: https://lore.kernel.org/r/20210302224916.13980-2-song.bao.hua@hisilicon.com
Patchset: surface-sam
---
include/linux/interrupt.h | 4 ++++
kernel/irq/manage.c | 11 +++++++++--
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 967e25767153..76f1161a441a 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -61,6 +61,9 @@
* interrupt handler after suspending interrupts. For system
* wakeup devices users need to implement wakeup detection in
* their interrupt handlers.
+ * IRQF_NO_AUTOEN - Don't enable IRQ or NMI automatically when users request it.
+ * Users will enable it explicitly by enable_irq() or enable_nmi()
+ * later.
*/
#define IRQF_SHARED 0x00000080
#define IRQF_PROBE_SHARED 0x00000100
@@ -74,6 +77,7 @@
#define IRQF_NO_THREAD 0x00010000
#define IRQF_EARLY_RESUME 0x00020000
#define IRQF_COND_SUSPEND 0x00040000
+#define IRQF_NO_AUTOEN 0x00080000
#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 21ea370fccda..49288e941365 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1697,7 +1697,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
}
- if (irq_settings_can_autoenable(desc)) {
+ if (!(new->flags & IRQF_NO_AUTOEN) &&
+ irq_settings_can_autoenable(desc)) {
irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
} else {
/*
@@ -2090,10 +2091,15 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
* which interrupt is which (messes up the interrupt freeing
* logic etc).
*
+ * Also shared interrupts do not go well with disabling auto enable.
+ * The sharing interrupt might request it while it's still disabled
+ * and then wait for interrupts forever.
+ *
* Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
* it cannot be set along with IRQF_NO_SUSPEND.
*/
if (((irqflags & IRQF_SHARED) && !dev_id) ||
+ ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
(!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
return -EINVAL;
@@ -2249,7 +2255,8 @@ int request_nmi(unsigned int irq, irq_handler_t handler,
desc = irq_to_desc(irq);
- if (!desc || irq_settings_can_autoenable(desc) ||
+ if (!desc || (irq_settings_can_autoenable(desc) &&
+ !(irqflags & IRQF_NO_AUTOEN)) ||
!irq_settings_can_request(desc) ||
WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
!irq_supports_nmi(desc))
--
2.31.1
From fdca7a09d5270022355cdde51b2f95317af1e6fa Mon Sep 17 00:00:00 2001
From: Tian Tao <tiantao6@hisilicon.com>
Date: Wed, 7 Apr 2021 15:00:52 +0800
Subject: [PATCH] platform/surface: aggregator: move to use request_irq by
IRQF_NO_AUTOEN flag
disable_irq() after request_irq() still has a time gap in which
interrupts can come. request_irq() with IRQF_NO_AUTOEN flag will
disable IRQ auto-enable because of requesting.
this patch is made base on "add IRQF_NO_AUTOEN for request_irq" which
is being merged: https://lore.kernel.org/patchwork/patch/1388765/
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/1617778852-26492-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/aggregator/controller.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index aa6f37b4f46e..00e38284885a 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -2483,7 +2483,8 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
* interrupt, and let the SAM resume callback during the controller
* resume process clear it.
*/
- const int irqf = IRQF_SHARED | IRQF_ONESHOT | IRQF_TRIGGER_RISING;
+ const int irqf = IRQF_SHARED | IRQF_ONESHOT |
+ IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
gpiod = gpiod_get(dev, "ssam_wakeup-int", GPIOD_ASIS);
if (IS_ERR(gpiod))
@@ -2501,7 +2502,6 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
return status;
ctrl->irq.num = irq;
- disable_irq(ctrl->irq.num);
return 0;
}
--
2.31.1
From 7a2a06bd6598d33335519271102ab2f5722e0913 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Wed, 5 May 2021 14:53:45 +0200
Subject: [PATCH] platform/surface: aggregator: Do not mark interrupt as shared
Having both IRQF_NO_AUTOEN and IRQF_SHARED set causes
request_threaded_irq() to return with -EINVAL (see comment in flag
validation in that function). As the interrupt is currently not shared
between multiple devices, drop the IRQF_SHARED flag.
Fixes: 507cf5a2f1e2 ("platform/surface: aggregator: move to use request_irq by IRQF_NO_AUTOEN flag")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/platform/surface/aggregator/controller.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index 00e38284885a..1f42fcd5d8c3 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -2483,8 +2483,7 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
* interrupt, and let the SAM resume callback during the controller
* resume process clear it.
*/
- const int irqf = IRQF_SHARED | IRQF_ONESHOT |
- IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
+ const int irqf = IRQF_ONESHOT | IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
gpiod = gpiod_get(dev, "ssam_wakeup-int", GPIOD_ASIS);
if (IS_ERR(gpiod))
--
2.31.1
From 71a7d75c951e4001b35779cf39f138487454362d Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 20 Apr 2021 11:44:02 +0300
Subject: [PATCH] platform/surface: aggregator: fix a bit test
The "funcs" variable is a u64. If "func" is more than 31 then the
BIT() shift will wrap instead of testing the high bits.
Fixes: c167b9c7e3d6 ("platform/surface: Add Surface Aggregator subsystem")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/YH6UUhJhGk3mk13b@mwanda
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
drivers/platform/surface/aggregator/controller.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index 1f42fcd5d8c3..8a70df60142c 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -1040,7 +1040,7 @@ static int ssam_dsm_load_u32(acpi_handle handle, u64 funcs, u64 func, u32 *ret)
union acpi_object *obj;
u64 val;
- if (!(funcs & BIT(func)))
+ if (!(funcs & BIT_ULL(func)))
return 0; /* Not supported, leave *ret at its default value */
obj = acpi_evaluate_dsm_typed(handle, &SSAM_SSH_DSM_GUID,
--
2.31.1
From 4bac02ecade55ad1c2dc1ebbca0510d8e05c8823 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Wed, 10 Mar 2021 23:53:28 +0100
Subject: [PATCH] HID: Add support for Surface Aggregator Module HID transport
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Add a HID transport driver to support integrated HID devices on newer
Microsoft Surface models (specifically 7th-generation, i.e. Surface
Laptop 3, Surface Book 3, and later).
On those models, the internal keyboard and touchpad (as well as some
other HID devices with currently unknown function) are connected via the
generic HID subsystem (TC=0x15) of the Surface System Aggregator Module
(SSAM). This subsystem provides a generic HID transport layer, support
for which is implemented by this driver.
Co-developed-by: Blaž Hrastnik <blaz@mxxn.io>
Signed-off-by: Blaž Hrastnik <blaz@mxxn.io>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Patchset: surface-sam
---
MAINTAINERS | 7 +
drivers/hid/Kconfig | 2 +
drivers/hid/Makefile | 2 +
drivers/hid/surface-hid/Kconfig | 28 +++
drivers/hid/surface-hid/Makefile | 6 +
drivers/hid/surface-hid/surface_hid.c | 253 +++++++++++++++++++
drivers/hid/surface-hid/surface_hid_core.c | 272 +++++++++++++++++++++
drivers/hid/surface-hid/surface_hid_core.h | 77 ++++++
8 files changed, 647 insertions(+)
create mode 100644 drivers/hid/surface-hid/Kconfig
create mode 100644 drivers/hid/surface-hid/Makefile
create mode 100644 drivers/hid/surface-hid/surface_hid.c
create mode 100644 drivers/hid/surface-hid/surface_hid_core.c
create mode 100644 drivers/hid/surface-hid/surface_hid_core.h
diff --git a/MAINTAINERS b/MAINTAINERS
index da1487d672a8..f54b22333ec6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11891,6 +11891,13 @@ S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git
F: drivers/platform/surface/
+MICROSOFT SURFACE HID TRANSPORT DRIVER
+M: Maximilian Luz <luzmaximilian@gmail.com>
+L: linux-input@vger.kernel.org
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/hid/surface-hid/
+
MICROSOFT SURFACE HOT-PLUG DRIVER
M: Maximilian Luz <luzmaximilian@gmail.com>
L: platform-driver-x86@vger.kernel.org
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 786b71ef7738..26e06097ba08 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -1206,4 +1206,6 @@ source "drivers/hid/intel-ish-hid/Kconfig"
source "drivers/hid/amd-sfh-hid/Kconfig"
+source "drivers/hid/surface-hid/Kconfig"
+
endmenu
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index c4f6d5c613dc..1044ed238856 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -145,3 +145,5 @@ obj-$(CONFIG_INTEL_ISH_HID) += intel-ish-hid/
obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ish-hid/
obj-$(CONFIG_AMD_SFH_HID) += amd-sfh-hid/
+
+obj-$(CONFIG_SURFACE_HID_CORE) += surface-hid/
diff --git a/drivers/hid/surface-hid/Kconfig b/drivers/hid/surface-hid/Kconfig
new file mode 100644
index 000000000000..642c7f0e64fe
--- /dev/null
+++ b/drivers/hid/surface-hid/Kconfig
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0+
+menu "Surface System Aggregator Module HID support"
+ depends on SURFACE_AGGREGATOR
+ depends on INPUT
+
+config SURFACE_HID
+ tristate "HID transport driver for Surface System Aggregator Module"
+ depends on SURFACE_AGGREGATOR_REGISTRY
+ select SURFACE_HID_CORE
+ help
+ Driver to support integrated HID devices on newer Microsoft Surface
+ models.
+
+ This driver provides support for the HID transport protocol provided
+ by the Surface Aggregator Module (i.e. the embedded controller) on
+ 7th-generation Microsoft Surface devices, i.e. Surface Book 3 and
+ Surface Laptop 3. On those models, it is mainly used to connect the
+ integrated touchpad and keyboard.
+
+ Say M or Y here, if you want support for integrated HID devices, i.e.
+ integrated touchpad and keyboard, on 7th generation Microsoft Surface
+ models.
+
+endmenu
+
+config SURFACE_HID_CORE
+ tristate
+ select HID
diff --git a/drivers/hid/surface-hid/Makefile b/drivers/hid/surface-hid/Makefile
new file mode 100644
index 000000000000..62fc04632d3d
--- /dev/null
+++ b/drivers/hid/surface-hid/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Makefile - Surface System Aggregator Module (SSAM) HID transport driver.
+#
+obj-$(CONFIG_SURFACE_HID_CORE) += surface_hid_core.o
+obj-$(CONFIG_SURFACE_HID) += surface_hid.o
diff --git a/drivers/hid/surface-hid/surface_hid.c b/drivers/hid/surface-hid/surface_hid.c
new file mode 100644
index 000000000000..3477b31611ae
--- /dev/null
+++ b/drivers/hid/surface-hid/surface_hid.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface System Aggregator Module (SSAM) HID transport driver for the
+ * generic HID interface (HID/TC=0x15 subsystem). Provides support for
+ * integrated HID devices on Surface Laptop 3, Book 3, and later.
+ *
+ * Copyright (C) 2019-2021 Blaž Hrastnik <blaz@mxxn.io>,
+ * Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/hid.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
+
+#include "surface_hid_core.h"
+
+
+/* -- SAM interface. -------------------------------------------------------- */
+
+struct surface_hid_buffer_slice {
+ __u8 entry;
+ __le32 offset;
+ __le32 length;
+ __u8 end;
+ __u8 data[];
+} __packed;
+
+static_assert(sizeof(struct surface_hid_buffer_slice) == 10);
+
+enum surface_hid_cid {
+ SURFACE_HID_CID_OUTPUT_REPORT = 0x01,
+ SURFACE_HID_CID_GET_FEATURE_REPORT = 0x02,
+ SURFACE_HID_CID_SET_FEATURE_REPORT = 0x03,
+ SURFACE_HID_CID_GET_DESCRIPTOR = 0x04,
+};
+
+static int ssam_hid_get_descriptor(struct surface_hid_device *shid, u8 entry, u8 *buf, size_t len)
+{
+ u8 buffer[sizeof(struct surface_hid_buffer_slice) + 0x76];
+ struct surface_hid_buffer_slice *slice;
+ struct ssam_request rqst;
+ struct ssam_response rsp;
+ u32 buffer_len, offset, length;
+ int status;
+
+ /*
+ * Note: The 0x76 above has been chosen because that's what's used by
+ * the Windows driver. Together with the header, this leads to a 128
+ * byte payload in total.
+ */
+
+ buffer_len = ARRAY_SIZE(buffer) - sizeof(struct surface_hid_buffer_slice);
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.command_id = SURFACE_HID_CID_GET_DESCRIPTOR;
+ rqst.instance_id = shid->uid.instance;
+ rqst.flags = SSAM_REQUEST_HAS_RESPONSE;
+ rqst.length = sizeof(struct surface_hid_buffer_slice);
+ rqst.payload = buffer;
+
+ rsp.capacity = ARRAY_SIZE(buffer);
+ rsp.pointer = buffer;
+
+ slice = (struct surface_hid_buffer_slice *)buffer;
+ slice->entry = entry;
+ slice->end = 0;
+
+ offset = 0;
+ length = buffer_len;
+
+ while (!slice->end && offset < len) {
+ put_unaligned_le32(offset, &slice->offset);
+ put_unaligned_le32(length, &slice->length);
+
+ rsp.length = 0;
+
+ status = ssam_retry(ssam_request_sync_onstack, shid->ctrl, &rqst, &rsp,
+ sizeof(*slice));
+ if (status)
+ return status;
+
+ offset = get_unaligned_le32(&slice->offset);
+ length = get_unaligned_le32(&slice->length);
+
+ /* Don't mess stuff up in case we receive garbage. */
+ if (length > buffer_len || offset > len)
+ return -EPROTO;
+
+ if (offset + length > len)
+ length = len - offset;
+
+ memcpy(buf + offset, &slice->data[0], length);
+
+ offset += length;
+ length = buffer_len;
+ }
+
+ if (offset != len) {
+ dev_err(shid->dev, "unexpected descriptor length: got %u, expected %zu\n",
+ offset, len);
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+static int ssam_hid_set_raw_report(struct surface_hid_device *shid, u8 rprt_id, bool feature,
+ u8 *buf, size_t len)
+{
+ struct ssam_request rqst;
+ u8 cid;
+
+ if (feature)
+ cid = SURFACE_HID_CID_SET_FEATURE_REPORT;
+ else
+ cid = SURFACE_HID_CID_OUTPUT_REPORT;
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.instance_id = shid->uid.instance;
+ rqst.command_id = cid;
+ rqst.flags = 0;
+ rqst.length = len;
+ rqst.payload = buf;
+
+ buf[0] = rprt_id;
+
+ return ssam_retry(ssam_request_sync, shid->ctrl, &rqst, NULL);
+}
+
+static int ssam_hid_get_raw_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ struct ssam_request rqst;
+ struct ssam_response rsp;
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.instance_id = shid->uid.instance;
+ rqst.command_id = SURFACE_HID_CID_GET_FEATURE_REPORT;
+ rqst.flags = 0;
+ rqst.length = sizeof(rprt_id);
+ rqst.payload = &rprt_id;
+
+ rsp.capacity = len;
+ rsp.length = 0;
+ rsp.pointer = buf;
+
+ return ssam_retry(ssam_request_sync_onstack, shid->ctrl, &rqst, &rsp, sizeof(rprt_id));
+}
+
+static u32 ssam_hid_event_fn(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+ struct surface_hid_device *shid = container_of(nf, struct surface_hid_device, notif);
+
+ if (event->command_id != 0x00)
+ return 0;
+
+ hid_input_report(shid->hid, HID_INPUT_REPORT, (u8 *)&event->data[0], event->length, 0);
+ return SSAM_NOTIF_HANDLED;
+}
+
+
+/* -- Transport driver. ----------------------------------------------------- */
+
+static int shid_output_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ int status;
+
+ status = ssam_hid_set_raw_report(shid, rprt_id, false, buf, len);
+ return status >= 0 ? len : status;
+}
+
+static int shid_get_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ int status;
+
+ status = ssam_hid_get_raw_report(shid, rprt_id, buf, len);
+ return status >= 0 ? len : status;
+}
+
+static int shid_set_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ int status;
+
+ status = ssam_hid_set_raw_report(shid, rprt_id, true, buf, len);
+ return status >= 0 ? len : status;
+}
+
+
+/* -- Driver setup. --------------------------------------------------------- */
+
+static int surface_hid_probe(struct ssam_device *sdev)
+{
+ struct surface_hid_device *shid;
+
+ shid = devm_kzalloc(&sdev->dev, sizeof(*shid), GFP_KERNEL);
+ if (!shid)
+ return -ENOMEM;
+
+ shid->dev = &sdev->dev;
+ shid->ctrl = sdev->ctrl;
+ shid->uid = sdev->uid;
+
+ shid->notif.base.priority = 1;
+ shid->notif.base.fn = ssam_hid_event_fn;
+ shid->notif.event.reg = SSAM_EVENT_REGISTRY_REG;
+ shid->notif.event.id.target_category = sdev->uid.category;
+ shid->notif.event.id.instance = sdev->uid.instance;
+ shid->notif.event.mask = SSAM_EVENT_MASK_STRICT;
+ shid->notif.event.flags = 0;
+
+ shid->ops.get_descriptor = ssam_hid_get_descriptor;
+ shid->ops.output_report = shid_output_report;
+ shid->ops.get_feature_report = shid_get_feature_report;
+ shid->ops.set_feature_report = shid_set_feature_report;
+
+ ssam_device_set_drvdata(sdev, shid);
+ return surface_hid_device_add(shid);
+}
+
+static void surface_hid_remove(struct ssam_device *sdev)
+{
+ surface_hid_device_destroy(ssam_device_get_drvdata(sdev));
+}
+
+static const struct ssam_device_id surface_hid_match[] = {
+ { SSAM_SDEV(HID, 0x02, SSAM_ANY_IID, 0x00) },
+ { },
+};
+MODULE_DEVICE_TABLE(ssam, surface_hid_match);
+
+static struct ssam_device_driver surface_hid_driver = {
+ .probe = surface_hid_probe,
+ .remove = surface_hid_remove,
+ .match_table = surface_hid_match,
+ .driver = {
+ .name = "surface_hid",
+ .pm = &surface_hid_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_ssam_device_driver(surface_hid_driver);
+
+MODULE_AUTHOR("Blaž Hrastnik <blaz@mxxn.io>");
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("HID transport driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hid/surface-hid/surface_hid_core.c b/drivers/hid/surface-hid/surface_hid_core.c
new file mode 100644
index 000000000000..7b27ec392232
--- /dev/null
+++ b/drivers/hid/surface-hid/surface_hid_core.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Common/core components for the Surface System Aggregator Module (SSAM) HID
+ * transport driver. Provides support for integrated HID devices on Microsoft
+ * Surface models.
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/hid.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/usb/ch9.h>
+
+#include <linux/surface_aggregator/controller.h>
+
+#include "surface_hid_core.h"
+
+
+/* -- Device descriptor access. --------------------------------------------- */
+
+static int surface_hid_load_hid_descriptor(struct surface_hid_device *shid)
+{
+ int status;
+
+ status = shid->ops.get_descriptor(shid, SURFACE_HID_DESC_HID,
+ (u8 *)&shid->hid_desc, sizeof(shid->hid_desc));
+ if (status)
+ return status;
+
+ if (shid->hid_desc.desc_len != sizeof(shid->hid_desc)) {
+ dev_err(shid->dev, "unexpected HID descriptor length: got %u, expected %zu\n",
+ shid->hid_desc.desc_len, sizeof(shid->hid_desc));
+ return -EPROTO;
+ }
+
+ if (shid->hid_desc.desc_type != HID_DT_HID) {
+ dev_err(shid->dev, "unexpected HID descriptor type: got %#04x, expected %#04x\n",
+ shid->hid_desc.desc_type, HID_DT_HID);
+ return -EPROTO;
+ }
+
+ if (shid->hid_desc.num_descriptors != 1) {
+ dev_err(shid->dev, "unexpected number of descriptors: got %u, expected 1\n",
+ shid->hid_desc.num_descriptors);
+ return -EPROTO;
+ }
+
+ if (shid->hid_desc.report_desc_type != HID_DT_REPORT) {
+ dev_err(shid->dev, "unexpected report descriptor type: got %#04x, expected %#04x\n",
+ shid->hid_desc.report_desc_type, HID_DT_REPORT);
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+static int surface_hid_load_device_attributes(struct surface_hid_device *shid)
+{
+ int status;
+
+ status = shid->ops.get_descriptor(shid, SURFACE_HID_DESC_ATTRS,
+ (u8 *)&shid->attrs, sizeof(shid->attrs));
+ if (status)
+ return status;
+
+ if (get_unaligned_le32(&shid->attrs.length) != sizeof(shid->attrs)) {
+ dev_err(shid->dev, "unexpected attribute length: got %u, expected %zu\n",
+ get_unaligned_le32(&shid->attrs.length), sizeof(shid->attrs));
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+
+/* -- Transport driver (common). -------------------------------------------- */
+
+static int surface_hid_start(struct hid_device *hid)
+{
+ struct surface_hid_device *shid = hid->driver_data;
+
+ return ssam_notifier_register(shid->ctrl, &shid->notif);
+}
+
+static void surface_hid_stop(struct hid_device *hid)
+{
+ struct surface_hid_device *shid = hid->driver_data;
+
+ /* Note: This call will log errors for us, so ignore them here. */
+ ssam_notifier_unregister(shid->ctrl, &shid->notif);
+}
+
+static int surface_hid_open(struct hid_device *hid)
+{
+ return 0;
+}
+
+static void surface_hid_close(struct hid_device *hid)
+{
+}
+
+static int surface_hid_parse(struct hid_device *hid)
+{
+ struct surface_hid_device *shid = hid->driver_data;
+ size_t len = get_unaligned_le16(&shid->hid_desc.report_desc_len);
+ u8 *buf;
+ int status;
+
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ status = shid->ops.get_descriptor(shid, SURFACE_HID_DESC_REPORT, buf, len);
+ if (!status)
+ status = hid_parse_report(hid, buf, len);
+
+ kfree(buf);
+ return status;
+}
+
+static int surface_hid_raw_request(struct hid_device *hid, unsigned char reportnum, u8 *buf,
+ size_t len, unsigned char rtype, int reqtype)
+{
+ struct surface_hid_device *shid = hid->driver_data;
+
+ if (rtype == HID_OUTPUT_REPORT && reqtype == HID_REQ_SET_REPORT)
+ return shid->ops.output_report(shid, reportnum, buf, len);
+
+ else if (rtype == HID_FEATURE_REPORT && reqtype == HID_REQ_GET_REPORT)
+ return shid->ops.get_feature_report(shid, reportnum, buf, len);
+
+ else if (rtype == HID_FEATURE_REPORT && reqtype == HID_REQ_SET_REPORT)
+ return shid->ops.set_feature_report(shid, reportnum, buf, len);
+
+ return -EIO;
+}
+
+static struct hid_ll_driver surface_hid_ll_driver = {
+ .start = surface_hid_start,
+ .stop = surface_hid_stop,
+ .open = surface_hid_open,
+ .close = surface_hid_close,
+ .parse = surface_hid_parse,
+ .raw_request = surface_hid_raw_request,
+};
+
+
+/* -- Common device setup. -------------------------------------------------- */
+
+int surface_hid_device_add(struct surface_hid_device *shid)
+{
+ int status;
+
+ status = surface_hid_load_hid_descriptor(shid);
+ if (status)
+ return status;
+
+ status = surface_hid_load_device_attributes(shid);
+ if (status)
+ return status;
+
+ shid->hid = hid_allocate_device();
+ if (IS_ERR(shid->hid))
+ return PTR_ERR(shid->hid);
+
+ shid->hid->dev.parent = shid->dev;
+ shid->hid->bus = BUS_HOST;
+ shid->hid->vendor = cpu_to_le16(shid->attrs.vendor);
+ shid->hid->product = cpu_to_le16(shid->attrs.product);
+ shid->hid->version = cpu_to_le16(shid->hid_desc.hid_version);
+ shid->hid->country = shid->hid_desc.country_code;
+
+ snprintf(shid->hid->name, sizeof(shid->hid->name), "Microsoft Surface %04X:%04X",
+ shid->hid->vendor, shid->hid->product);
+
+ strscpy(shid->hid->phys, dev_name(shid->dev), sizeof(shid->hid->phys));
+
+ shid->hid->driver_data = shid;
+ shid->hid->ll_driver = &surface_hid_ll_driver;
+
+ status = hid_add_device(shid->hid);
+ if (status)
+ hid_destroy_device(shid->hid);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(surface_hid_device_add);
+
+void surface_hid_device_destroy(struct surface_hid_device *shid)
+{
+ hid_destroy_device(shid->hid);
+}
+EXPORT_SYMBOL_GPL(surface_hid_device_destroy);
+
+
+/* -- PM ops. --------------------------------------------------------------- */
+
+#ifdef CONFIG_PM_SLEEP
+
+static int surface_hid_suspend(struct device *dev)
+{
+ struct surface_hid_device *d = dev_get_drvdata(dev);
+
+ if (d->hid->driver && d->hid->driver->suspend)
+ return d->hid->driver->suspend(d->hid, PMSG_SUSPEND);
+
+ return 0;
+}
+
+static int surface_hid_resume(struct device *dev)
+{
+ struct surface_hid_device *d = dev_get_drvdata(dev);
+
+ if (d->hid->driver && d->hid->driver->resume)
+ return d->hid->driver->resume(d->hid);
+
+ return 0;
+}
+
+static int surface_hid_freeze(struct device *dev)
+{
+ struct surface_hid_device *d = dev_get_drvdata(dev);
+
+ if (d->hid->driver && d->hid->driver->suspend)
+ return d->hid->driver->suspend(d->hid, PMSG_FREEZE);
+
+ return 0;
+}
+
+static int surface_hid_poweroff(struct device *dev)
+{
+ struct surface_hid_device *d = dev_get_drvdata(dev);
+
+ if (d->hid->driver && d->hid->driver->suspend)
+ return d->hid->driver->suspend(d->hid, PMSG_HIBERNATE);
+
+ return 0;
+}
+
+static int surface_hid_restore(struct device *dev)
+{
+ struct surface_hid_device *d = dev_get_drvdata(dev);
+
+ if (d->hid->driver && d->hid->driver->reset_resume)
+ return d->hid->driver->reset_resume(d->hid);
+
+ return 0;
+}
+
+const struct dev_pm_ops surface_hid_pm_ops = {
+ .freeze = surface_hid_freeze,
+ .thaw = surface_hid_resume,
+ .suspend = surface_hid_suspend,
+ .resume = surface_hid_resume,
+ .poweroff = surface_hid_poweroff,
+ .restore = surface_hid_restore,
+};
+EXPORT_SYMBOL_GPL(surface_hid_pm_ops);
+
+#else /* CONFIG_PM_SLEEP */
+
+const struct dev_pm_ops surface_hid_pm_ops = { };
+EXPORT_SYMBOL_GPL(surface_hid_pm_ops);
+
+#endif /* CONFIG_PM_SLEEP */
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("HID transport driver core for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hid/surface-hid/surface_hid_core.h b/drivers/hid/surface-hid/surface_hid_core.h
new file mode 100644
index 000000000000..4b1a7b57e035
--- /dev/null
+++ b/drivers/hid/surface-hid/surface_hid_core.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Common/core components for the Surface System Aggregator Module (SSAM) HID
+ * transport driver. Provides support for integrated HID devices on Microsoft
+ * Surface models.
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#ifndef SURFACE_HID_CORE_H
+#define SURFACE_HID_CORE_H
+
+#include <linux/hid.h>
+#include <linux/pm.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
+
+enum surface_hid_descriptor_entry {
+ SURFACE_HID_DESC_HID = 0,
+ SURFACE_HID_DESC_REPORT = 1,
+ SURFACE_HID_DESC_ATTRS = 2,
+};
+
+struct surface_hid_descriptor {
+ __u8 desc_len; /* = 9 */
+ __u8 desc_type; /* = HID_DT_HID */
+ __le16 hid_version;
+ __u8 country_code;
+ __u8 num_descriptors; /* = 1 */
+
+ __u8 report_desc_type; /* = HID_DT_REPORT */
+ __le16 report_desc_len;
+} __packed;
+
+static_assert(sizeof(struct surface_hid_descriptor) == 9);
+
+struct surface_hid_attributes {
+ __le32 length;
+ __le16 vendor;
+ __le16 product;
+ __le16 version;
+ __u8 _unknown[22];
+} __packed;
+
+static_assert(sizeof(struct surface_hid_attributes) == 32);
+
+struct surface_hid_device;
+
+struct surface_hid_device_ops {
+ int (*get_descriptor)(struct surface_hid_device *shid, u8 entry, u8 *buf, size_t len);
+ int (*output_report)(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len);
+ int (*get_feature_report)(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len);
+ int (*set_feature_report)(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len);
+};
+
+struct surface_hid_device {
+ struct device *dev;
+ struct ssam_controller *ctrl;
+ struct ssam_device_uid uid;
+
+ struct surface_hid_descriptor hid_desc;
+ struct surface_hid_attributes attrs;
+
+ struct ssam_event_notifier notif;
+ struct hid_device *hid;
+
+ struct surface_hid_device_ops ops;
+};
+
+int surface_hid_device_add(struct surface_hid_device *shid);
+void surface_hid_device_destroy(struct surface_hid_device *shid);
+
+extern const struct dev_pm_ops surface_hid_pm_ops;
+
+#endif /* SURFACE_HID_CORE_H */
--
2.31.1
From 61201d7c3512e3b7a74cb76f06db959e50a60d0f Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Wed, 10 Mar 2021 23:53:29 +0100
Subject: [PATCH] HID: surface-hid: Add support for legacy keyboard interface
Add support for the legacy keyboard (KBD/TC=0x08) HID transport layer of
the Surface System Aggregator Module (SSAM) to the Surface HID driver.
On Surface Laptops 1 and 2, this interface is used to connect the
integrated keyboard.
Note that this subsystem interface essentially provides a limited HID
transport layer. In contrast to the generic HID interface (TC=0x15) used
on newer Surface models, this interface only allows (as far as we know)
for a single device to be connected and is otherwise severely limited in
terms of support for feature- and output-reports. Specifically, only
caps-lock-LED output-reports and a single read-only feature-report are
supported.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Patchset: surface-sam
---
drivers/hid/surface-hid/Kconfig | 14 ++
drivers/hid/surface-hid/Makefile | 1 +
drivers/hid/surface-hid/surface_kbd.c | 300 ++++++++++++++++++++++++++
3 files changed, 315 insertions(+)
create mode 100644 drivers/hid/surface-hid/surface_kbd.c
diff --git a/drivers/hid/surface-hid/Kconfig b/drivers/hid/surface-hid/Kconfig
index 642c7f0e64fe..7ce9b5d641eb 100644
--- a/drivers/hid/surface-hid/Kconfig
+++ b/drivers/hid/surface-hid/Kconfig
@@ -21,6 +21,20 @@ config SURFACE_HID
integrated touchpad and keyboard, on 7th generation Microsoft Surface
models.
+config SURFACE_KBD
+ tristate "HID keyboard transport driver for Surface System Aggregator Module"
+ select SURFACE_HID_CORE
+ help
+ Driver to support HID keyboards on Surface Laptop 1 and 2 devices.
+
+ This driver provides support for the HID transport protocol provided
+ by the Surface Aggregator Module (i.e. the embedded controller) on
+ Microsoft Surface Laptops 1 and 2. It is used to connect the
+ integrated keyboard on those devices.
+
+ Say M or Y here, if you want support for the integrated keyboard on
+ Microsoft Surface Laptops 1 and 2.
+
endmenu
config SURFACE_HID_CORE
diff --git a/drivers/hid/surface-hid/Makefile b/drivers/hid/surface-hid/Makefile
index 62fc04632d3d..4ae11cf09b25 100644
--- a/drivers/hid/surface-hid/Makefile
+++ b/drivers/hid/surface-hid/Makefile
@@ -4,3 +4,4 @@
#
obj-$(CONFIG_SURFACE_HID_CORE) += surface_hid_core.o
obj-$(CONFIG_SURFACE_HID) += surface_hid.o
+obj-$(CONFIG_SURFACE_KBD) += surface_kbd.o
diff --git a/drivers/hid/surface-hid/surface_kbd.c b/drivers/hid/surface-hid/surface_kbd.c
new file mode 100644
index 000000000000..0635341bc517
--- /dev/null
+++ b/drivers/hid/surface-hid/surface_kbd.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface System Aggregator Module (SSAM) HID transport driver for the legacy
+ * keyboard interface (KBD/TC=0x08 subsystem). Provides support for the
+ * integrated HID keyboard on Surface Laptops 1 and 2.
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/hid.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/controller.h>
+
+#include "surface_hid_core.h"
+
+
+/* -- SAM interface (KBD). -------------------------------------------------- */
+
+#define KBD_FEATURE_REPORT_SIZE 7 /* 6 + report ID */
+
+enum surface_kbd_cid {
+ SURFACE_KBD_CID_GET_DESCRIPTOR = 0x00,
+ SURFACE_KBD_CID_SET_CAPSLOCK_LED = 0x01,
+ SURFACE_KBD_CID_EVT_INPUT_GENERIC = 0x03,
+ SURFACE_KBD_CID_EVT_INPUT_HOTKEYS = 0x04,
+ SURFACE_KBD_CID_GET_FEATURE_REPORT = 0x0b,
+};
+
+static int ssam_kbd_get_descriptor(struct surface_hid_device *shid, u8 entry, u8 *buf, size_t len)
+{
+ struct ssam_request rqst;
+ struct ssam_response rsp;
+ int status;
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.command_id = SURFACE_KBD_CID_GET_DESCRIPTOR;
+ rqst.instance_id = shid->uid.instance;
+ rqst.flags = SSAM_REQUEST_HAS_RESPONSE;
+ rqst.length = sizeof(entry);
+ rqst.payload = &entry;
+
+ rsp.capacity = len;
+ rsp.length = 0;
+ rsp.pointer = buf;
+
+ status = ssam_retry(ssam_request_sync_onstack, shid->ctrl, &rqst, &rsp, sizeof(entry));
+ if (status)
+ return status;
+
+ if (rsp.length != len) {
+ dev_err(shid->dev, "invalid descriptor length: got %zu, expected, %zu\n",
+ rsp.length, len);
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+static int ssam_kbd_set_caps_led(struct surface_hid_device *shid, bool value)
+{
+ struct ssam_request rqst;
+ u8 value_u8 = value;
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.command_id = SURFACE_KBD_CID_SET_CAPSLOCK_LED;
+ rqst.instance_id = shid->uid.instance;
+ rqst.flags = 0;
+ rqst.length = sizeof(value_u8);
+ rqst.payload = &value_u8;
+
+ return ssam_retry(ssam_request_sync_onstack, shid->ctrl, &rqst, NULL, sizeof(value_u8));
+}
+
+static int ssam_kbd_get_feature_report(struct surface_hid_device *shid, u8 *buf, size_t len)
+{
+ struct ssam_request rqst;
+ struct ssam_response rsp;
+ u8 payload = 0;
+ int status;
+
+ rqst.target_category = shid->uid.category;
+ rqst.target_id = shid->uid.target;
+ rqst.command_id = SURFACE_KBD_CID_GET_FEATURE_REPORT;
+ rqst.instance_id = shid->uid.instance;
+ rqst.flags = SSAM_REQUEST_HAS_RESPONSE;
+ rqst.length = sizeof(payload);
+ rqst.payload = &payload;
+
+ rsp.capacity = len;
+ rsp.length = 0;
+ rsp.pointer = buf;
+
+ status = ssam_retry(ssam_request_sync_onstack, shid->ctrl, &rqst, &rsp, sizeof(payload));
+ if (status)
+ return status;
+
+ if (rsp.length != len) {
+ dev_err(shid->dev, "invalid feature report length: got %zu, expected, %zu\n",
+ rsp.length, len);
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+static bool ssam_kbd_is_input_event(const struct ssam_event *event)
+{
+ if (event->command_id == SURFACE_KBD_CID_EVT_INPUT_GENERIC)
+ return true;
+
+ if (event->command_id == SURFACE_KBD_CID_EVT_INPUT_HOTKEYS)
+ return true;
+
+ return false;
+}
+
+static u32 ssam_kbd_event_fn(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+ struct surface_hid_device *shid = container_of(nf, struct surface_hid_device, notif);
+
+ /*
+ * Check against device UID manually, as registry and device target
+ * category doesn't line up.
+ */
+
+ if (shid->uid.category != event->target_category)
+ return 0;
+
+ if (shid->uid.target != event->target_id)
+ return 0;
+
+ if (shid->uid.instance != event->instance_id)
+ return 0;
+
+ if (!ssam_kbd_is_input_event(event))
+ return 0;
+
+ hid_input_report(shid->hid, HID_INPUT_REPORT, (u8 *)&event->data[0], event->length, 0);
+ return SSAM_NOTIF_HANDLED;
+}
+
+
+/* -- Transport driver (KBD). ----------------------------------------------- */
+
+static int skbd_get_caps_led_value(struct hid_device *hid, u8 rprt_id, u8 *buf, size_t len)
+{
+ struct hid_field *field;
+ unsigned int offset, size;
+ int i;
+
+ /* Get LED field. */
+ field = hidinput_get_led_field(hid);
+ if (!field)
+ return -ENOENT;
+
+ /* Check if we got the correct report. */
+ if (len != hid_report_len(field->report))
+ return -ENOENT;
+
+ if (rprt_id != field->report->id)
+ return -ENOENT;
+
+ /* Get caps lock LED index. */
+ for (i = 0; i < field->report_count; i++)
+ if ((field->usage[i].hid & 0xffff) == 0x02)
+ break;
+
+ if (i == field->report_count)
+ return -ENOENT;
+
+ /* Extract value. */
+ size = field->report_size;
+ offset = field->report_offset + i * size;
+ return !!hid_field_extract(hid, buf + 1, size, offset);
+}
+
+static int skbd_output_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ int caps_led;
+ int status;
+
+ caps_led = skbd_get_caps_led_value(shid->hid, rprt_id, buf, len);
+ if (caps_led < 0)
+ return -EIO; /* Only caps LED output reports are supported. */
+
+ status = ssam_kbd_set_caps_led(shid, caps_led);
+ if (status < 0)
+ return status;
+
+ return len;
+}
+
+static int skbd_get_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ u8 report[KBD_FEATURE_REPORT_SIZE];
+ int status;
+
+ /*
+ * The keyboard only has a single hard-coded read-only feature report
+ * of size KBD_FEATURE_REPORT_SIZE. Try to load it and compare its
+ * report ID against the requested one.
+ */
+
+ if (len < ARRAY_SIZE(report))
+ return -ENOSPC;
+
+ status = ssam_kbd_get_feature_report(shid, report, ARRAY_SIZE(report));
+ if (status < 0)
+ return status;
+
+ if (rprt_id != report[0])
+ return -ENOENT;
+
+ memcpy(buf, report, ARRAY_SIZE(report));
+ return len;
+}
+
+static int skbd_set_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len)
+{
+ /* Not supported. See skbd_get_feature_report() for details. */
+ return -EIO;
+}
+
+
+/* -- Driver setup. --------------------------------------------------------- */
+
+static int surface_kbd_probe(struct platform_device *pdev)
+{
+ struct ssam_controller *ctrl;
+ struct surface_hid_device *shid;
+
+ /* Add device link to EC. */
+ ctrl = ssam_client_bind(&pdev->dev);
+ if (IS_ERR(ctrl))
+ return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl);
+
+ shid = devm_kzalloc(&pdev->dev, sizeof(*shid), GFP_KERNEL);
+ if (!shid)
+ return -ENOMEM;
+
+ shid->dev = &pdev->dev;
+ shid->ctrl = ctrl;
+
+ shid->uid.domain = SSAM_DOMAIN_SERIALHUB;
+ shid->uid.category = SSAM_SSH_TC_KBD;
+ shid->uid.target = 2;
+ shid->uid.instance = 0;
+ shid->uid.function = 0;
+
+ shid->notif.base.priority = 1;
+ shid->notif.base.fn = ssam_kbd_event_fn;
+ shid->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
+ shid->notif.event.id.target_category = shid->uid.category;
+ shid->notif.event.id.instance = shid->uid.instance;
+ shid->notif.event.mask = SSAM_EVENT_MASK_NONE;
+ shid->notif.event.flags = 0;
+
+ shid->ops.get_descriptor = ssam_kbd_get_descriptor;
+ shid->ops.output_report = skbd_output_report;
+ shid->ops.get_feature_report = skbd_get_feature_report;
+ shid->ops.set_feature_report = skbd_set_feature_report;
+
+ platform_set_drvdata(pdev, shid);
+ return surface_hid_device_add(shid);
+}
+
+static int surface_kbd_remove(struct platform_device *pdev)
+{
+ surface_hid_device_destroy(platform_get_drvdata(pdev));
+ return 0;
+}
+
+static const struct acpi_device_id surface_kbd_match[] = {
+ { "MSHW0096" },
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, surface_kbd_match);
+
+static struct platform_driver surface_kbd_driver = {
+ .probe = surface_kbd_probe,
+ .remove = surface_kbd_remove,
+ .driver = {
+ .name = "surface_keyboard",
+ .acpi_match_table = surface_kbd_match,
+ .pm = &surface_hid_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_platform_driver(surface_kbd_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("HID legacy transport driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
--
2.31.1
From 5b5d66c4569050cf2d15073cef9ec0fee33dfa3c Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 23 Apr 2021 00:51:22 +0200
Subject: [PATCH] HID: surface-hid: Fix integer endian conversion
We want to convert from 16 bit (unsigned) little endian values contained
in a packed struct to CPU native endian values here, not the other way
around. So replace cpu_to_le16() with get_unaligned_le16(), using the
latter instead of le16_to_cpu() to acknowledge that we are reading from
a packed struct.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: b05ff1002a5c ("HID: Add support for Surface Aggregator Module HID transport")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/hid/surface-hid/surface_hid_core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/hid/surface-hid/surface_hid_core.c b/drivers/hid/surface-hid/surface_hid_core.c
index 7b27ec392232..5571e74abe91 100644
--- a/drivers/hid/surface-hid/surface_hid_core.c
+++ b/drivers/hid/surface-hid/surface_hid_core.c
@@ -168,9 +168,9 @@ int surface_hid_device_add(struct surface_hid_device *shid)
shid->hid->dev.parent = shid->dev;
shid->hid->bus = BUS_HOST;
- shid->hid->vendor = cpu_to_le16(shid->attrs.vendor);
- shid->hid->product = cpu_to_le16(shid->attrs.product);
- shid->hid->version = cpu_to_le16(shid->hid_desc.hid_version);
+ shid->hid->vendor = get_unaligned_le16(&shid->attrs.vendor);
+ shid->hid->product = get_unaligned_le16(&shid->attrs.product);
+ shid->hid->version = get_unaligned_le16(&shid->hid_desc.hid_version);
shid->hid->country = shid->hid_desc.country_code;
snprintf(shid->hid->name, sizeof(shid->hid->name), "Microsoft Surface %04X:%04X",
--
2.31.1
From 3e16741959dfab7d9bbcab0c1c7f28f5cd5b598e Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 6 Apr 2021 01:41:25 +0200
Subject: [PATCH] power: supply: Add battery driver for Surface Aggregator
Module
On newer Microsoft Surface models (specifically 7th-generation, i.e.
Surface Pro 7, Surface Book 3, Surface Laptop 3, and Surface Laptop Go),
battery and AC status/information is no longer handled via standard ACPI
devices, but instead directly via the Surface System Aggregator Module
(SSAM), i.e. the embedded controller on those devices.
While on previous generation models, battery status is also handled via
SSAM, an ACPI shim was present to translate the standard ACPI battery
interface to SSAM requests. The SSAM interface itself, which is modeled
closely after the ACPI interface, has not changed.
This commit introduces a new SSAM client device driver to support
battery status/information via the aforementioned interface on said
Surface models. It is in parts based on the standard ACPI battery
driver.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Patchset: surface-sam
---
.../ABI/testing/sysfs-class-power-surface | 15 +
MAINTAINERS | 7 +
drivers/power/supply/Kconfig | 16 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/surface_battery.c | 865 ++++++++++++++++++
5 files changed, 904 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-power-surface
create mode 100644 drivers/power/supply/surface_battery.c
diff --git a/Documentation/ABI/testing/sysfs-class-power-surface b/Documentation/ABI/testing/sysfs-class-power-surface
new file mode 100644
index 000000000000..79cde4dcf2f5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-power-surface
@@ -0,0 +1,15 @@
+What: /sys/class/power_supply/<supply_name>/alarm
+Date: April 2021
+KernelVersion: 5.13
+Contact: Maximilian Luz <luzmaximilian@gmail.com>
+Description:
+ Battery trip point. When the remaining battery capacity crosses this
+ value in either direction, the system will be notified and if
+ necessary woken.
+
+ Set to zero to clear/disable.
+
+ Access: Read, Write
+
+ Valid values: In micro-Wh or micro-Ah, depending on the power unit
+ of the battery
diff --git a/MAINTAINERS b/MAINTAINERS
index f54b22333ec6..7ee93b732270 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11868,6 +11868,13 @@ F: drivers/scsi/smartpqi/smartpqi*.[ch]
F: include/linux/cciss*.h
F: include/uapi/linux/cciss*.h
+MICROSOFT SURFACE BATTERY AND AC DRIVERS
+M: Maximilian Luz <luzmaximilian@gmail.com>
+L: linux-pm@vger.kernel.org
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/power/supply/surface_battery.c
+
MICROSOFT SURFACE DTX DRIVER
M: Maximilian Luz <luzmaximilian@gmail.com>
L: platform-driver-x86@vger.kernel.org
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 006b95eca673..cebeff10d543 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -801,4 +801,20 @@ config BATTERY_ACER_A500
help
Say Y to include support for Acer Iconia Tab A500 battery fuel gauge.
+config BATTERY_SURFACE
+ tristate "Battery driver for 7th-generation Microsoft Surface devices"
+ depends on SURFACE_AGGREGATOR_REGISTRY
+ help
+ Driver for battery devices connected via/managed by the Surface System
+ Aggregator Module (SSAM).
+
+ This driver provides battery-information and -status support for
+ Surface devices where said data is not exposed via the standard ACPI
+ devices. On those models (7th-generation), battery-information is
+ instead handled directly via SSAM client devices and this driver.
+
+ Say M or Y here to include battery status support for 7th-generation
+ Microsoft Surface devices, i.e. Surface Pro 7, Surface Laptop 3,
+ Surface Book 3, and Surface Laptop Go.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 5e5fdbbef531..134041538d2c 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -101,3 +101,4 @@ obj-$(CONFIG_CHARGER_BD99954) += bd99954-charger.o
obj-$(CONFIG_CHARGER_WILCO) += wilco-charger.o
obj-$(CONFIG_RN5T618_POWER) += rn5t618_power.o
obj-$(CONFIG_BATTERY_ACER_A500) += acer_a500_battery.o
+obj-$(CONFIG_BATTERY_SURFACE) += surface_battery.o
diff --git a/drivers/power/supply/surface_battery.c b/drivers/power/supply/surface_battery.c
new file mode 100644
index 000000000000..4116dd839ecd
--- /dev/null
+++ b/drivers/power/supply/surface_battery.c
@@ -0,0 +1,865 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Battery driver for 7th-generation Microsoft Surface devices via Surface
+ * System Aggregator Module (SSAM).
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/power_supply.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#include <linux/surface_aggregator/device.h>
+
+
+/* -- SAM interface. -------------------------------------------------------- */
+
+enum sam_event_cid_bat {
+ SAM_EVENT_CID_BAT_BIX = 0x15,
+ SAM_EVENT_CID_BAT_BST = 0x16,
+ SAM_EVENT_CID_BAT_ADP = 0x17,
+ SAM_EVENT_CID_BAT_PROT = 0x18,
+ SAM_EVENT_CID_BAT_DPTF = 0x53,
+};
+
+enum sam_battery_sta {
+ SAM_BATTERY_STA_OK = 0x0f,
+ SAM_BATTERY_STA_PRESENT = 0x10,
+};
+
+enum sam_battery_state {
+ SAM_BATTERY_STATE_DISCHARGING = BIT(0),
+ SAM_BATTERY_STATE_CHARGING = BIT(1),
+ SAM_BATTERY_STATE_CRITICAL = BIT(2),
+};
+
+enum sam_battery_power_unit {
+ SAM_BATTERY_POWER_UNIT_mW = 0,
+ SAM_BATTERY_POWER_UNIT_mA = 1,
+};
+
+/* Equivalent to data returned in ACPI _BIX method, revision 0. */
+struct spwr_bix {
+ u8 revision;
+ __le32 power_unit;
+ __le32 design_cap;
+ __le32 last_full_charge_cap;
+ __le32 technology;
+ __le32 design_voltage;
+ __le32 design_cap_warn;
+ __le32 design_cap_low;
+ __le32 cycle_count;
+ __le32 measurement_accuracy;
+ __le32 max_sampling_time;
+ __le32 min_sampling_time;
+ __le32 max_avg_interval;
+ __le32 min_avg_interval;
+ __le32 bat_cap_granularity_1;
+ __le32 bat_cap_granularity_2;
+ __u8 model[21];
+ __u8 serial[11];
+ __u8 type[5];
+ __u8 oem_info[21];
+} __packed;
+
+static_assert(sizeof(struct spwr_bix) == 119);
+
+/* Equivalent to data returned in ACPI _BST method. */
+struct spwr_bst {
+ __le32 state;
+ __le32 present_rate;
+ __le32 remaining_cap;
+ __le32 present_voltage;
+} __packed;
+
+static_assert(sizeof(struct spwr_bst) == 16);
+
+#define SPWR_BIX_REVISION 0
+#define SPWR_BATTERY_VALUE_UNKNOWN 0xffffffff
+
+/* Get battery status (_STA) */
+SSAM_DEFINE_SYNC_REQUEST_CL_R(ssam_bat_get_sta, __le32, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x01,
+});
+
+/* Get battery static information (_BIX). */
+SSAM_DEFINE_SYNC_REQUEST_CL_R(ssam_bat_get_bix, struct spwr_bix, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x02,
+});
+
+/* Get battery dynamic information (_BST). */
+SSAM_DEFINE_SYNC_REQUEST_CL_R(ssam_bat_get_bst, struct spwr_bst, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x03,
+});
+
+/* Set battery trip point (_BTP). */
+SSAM_DEFINE_SYNC_REQUEST_CL_W(ssam_bat_set_btp, __le32, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x04,
+});
+
+
+/* -- Device structures. ---------------------------------------------------- */
+
+struct spwr_psy_properties {
+ const char *name;
+ struct ssam_event_registry registry;
+};
+
+struct spwr_battery_device {
+ struct ssam_device *sdev;
+
+ char name[32];
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+
+ struct delayed_work update_work;
+
+ struct ssam_event_notifier notif;
+
+ struct mutex lock; /* Guards access to state data below. */
+ unsigned long timestamp;
+
+ __le32 sta;
+ struct spwr_bix bix;
+ struct spwr_bst bst;
+ u32 alarm;
+};
+
+
+/* -- Module parameters. ---------------------------------------------------- */
+
+static unsigned int cache_time = 1000;
+module_param(cache_time, uint, 0644);
+MODULE_PARM_DESC(cache_time, "battery state caching time in milliseconds [default: 1000]");
+
+
+/* -- State management. ----------------------------------------------------- */
+
+/*
+ * Delay for battery update quirk. See spwr_external_power_changed() below
+ * for more details.
+ */
+#define SPWR_AC_BAT_UPDATE_DELAY msecs_to_jiffies(5000)
+
+static bool spwr_battery_present(struct spwr_battery_device *bat)
+{
+ lockdep_assert_held(&bat->lock);
+
+ return le32_to_cpu(bat->sta) & SAM_BATTERY_STA_PRESENT;
+}
+
+static int spwr_battery_load_sta(struct spwr_battery_device *bat)
+{
+ lockdep_assert_held(&bat->lock);
+
+ return ssam_retry(ssam_bat_get_sta, bat->sdev, &bat->sta);
+}
+
+static int spwr_battery_load_bix(struct spwr_battery_device *bat)
+{
+ int status;
+
+ lockdep_assert_held(&bat->lock);
+
+ if (!spwr_battery_present(bat))
+ return 0;
+
+ status = ssam_retry(ssam_bat_get_bix, bat->sdev, &bat->bix);
+
+ /* Enforce NULL terminated strings in case anything goes wrong... */
+ bat->bix.model[ARRAY_SIZE(bat->bix.model) - 1] = 0;
+ bat->bix.serial[ARRAY_SIZE(bat->bix.serial) - 1] = 0;
+ bat->bix.type[ARRAY_SIZE(bat->bix.type) - 1] = 0;
+ bat->bix.oem_info[ARRAY_SIZE(bat->bix.oem_info) - 1] = 0;
+
+ return status;
+}
+
+static int spwr_battery_load_bst(struct spwr_battery_device *bat)
+{
+ lockdep_assert_held(&bat->lock);
+
+ if (!spwr_battery_present(bat))
+ return 0;
+
+ return ssam_retry(ssam_bat_get_bst, bat->sdev, &bat->bst);
+}
+
+static int spwr_battery_set_alarm_unlocked(struct spwr_battery_device *bat, u32 value)
+{
+ __le32 value_le = cpu_to_le32(value);
+
+ lockdep_assert_held(&bat->lock);
+
+ bat->alarm = value;
+ return ssam_retry(ssam_bat_set_btp, bat->sdev, &value_le);
+}
+
+static int spwr_battery_update_bst_unlocked(struct spwr_battery_device *bat, bool cached)
+{
+ unsigned long cache_deadline = bat->timestamp + msecs_to_jiffies(cache_time);
+ int status;
+
+ lockdep_assert_held(&bat->lock);
+
+ if (cached && bat->timestamp && time_is_after_jiffies(cache_deadline))
+ return 0;
+
+ status = spwr_battery_load_sta(bat);
+ if (status)
+ return status;
+
+ status = spwr_battery_load_bst(bat);
+ if (status)
+ return status;
+
+ bat->timestamp = jiffies;
+ return 0;
+}
+
+static int spwr_battery_update_bst(struct spwr_battery_device *bat, bool cached)
+{
+ int status;
+
+ mutex_lock(&bat->lock);
+ status = spwr_battery_update_bst_unlocked(bat, cached);
+ mutex_unlock(&bat->lock);
+
+ return status;
+}
+
+static int spwr_battery_update_bix_unlocked(struct spwr_battery_device *bat)
+{
+ int status;
+
+ lockdep_assert_held(&bat->lock);
+
+ status = spwr_battery_load_sta(bat);
+ if (status)
+ return status;
+
+ status = spwr_battery_load_bix(bat);
+ if (status)
+ return status;
+
+ status = spwr_battery_load_bst(bat);
+ if (status)
+ return status;
+
+ if (bat->bix.revision != SPWR_BIX_REVISION)
+ dev_warn(&bat->sdev->dev, "unsupported battery revision: %u\n", bat->bix.revision);
+
+ bat->timestamp = jiffies;
+ return 0;
+}
+
+static u32 sprw_battery_get_full_cap_safe(struct spwr_battery_device *bat)
+{
+ u32 full_cap = get_unaligned_le32(&bat->bix.last_full_charge_cap);
+
+ lockdep_assert_held(&bat->lock);
+
+ if (full_cap == 0 || full_cap == SPWR_BATTERY_VALUE_UNKNOWN)
+ full_cap = get_unaligned_le32(&bat->bix.design_cap);
+
+ return full_cap;
+}
+
+static bool spwr_battery_is_full(struct spwr_battery_device *bat)
+{
+ u32 state = get_unaligned_le32(&bat->bst.state);
+ u32 full_cap = sprw_battery_get_full_cap_safe(bat);
+ u32 remaining_cap = get_unaligned_le32(&bat->bst.remaining_cap);
+
+ lockdep_assert_held(&bat->lock);
+
+ return full_cap != SPWR_BATTERY_VALUE_UNKNOWN && full_cap != 0 &&
+ remaining_cap != SPWR_BATTERY_VALUE_UNKNOWN &&
+ remaining_cap >= full_cap &&
+ state == 0;
+}
+
+static int spwr_battery_recheck_full(struct spwr_battery_device *bat)
+{
+ bool present;
+ u32 unit;
+ int status;
+
+ mutex_lock(&bat->lock);
+ unit = get_unaligned_le32(&bat->bix.power_unit);
+ present = spwr_battery_present(bat);
+
+ status = spwr_battery_update_bix_unlocked(bat);
+ if (status)
+ goto out;
+
+ /* If battery has been attached, (re-)initialize alarm. */
+ if (!present && spwr_battery_present(bat)) {
+ u32 cap_warn = get_unaligned_le32(&bat->bix.design_cap_warn);
+
+ status = spwr_battery_set_alarm_unlocked(bat, cap_warn);
+ if (status)
+ goto out;
+ }
+
+ /*
+ * Warn if the unit has changed. This is something we genuinely don't
+ * expect to happen, so make this a big warning. If it does, we'll
+ * need to add support for it.
+ */
+ WARN_ON(unit != get_unaligned_le32(&bat->bix.power_unit));
+
+out:
+ mutex_unlock(&bat->lock);
+
+ if (!status)
+ power_supply_changed(bat->psy);
+
+ return status;
+}
+
+static int spwr_battery_recheck_status(struct spwr_battery_device *bat)
+{
+ int status;
+
+ status = spwr_battery_update_bst(bat, false);
+ if (!status)
+ power_supply_changed(bat->psy);
+
+ return status;
+}
+
+static u32 spwr_notify_bat(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+ struct spwr_battery_device *bat = container_of(nf, struct spwr_battery_device, notif);
+ int status;
+
+ dev_dbg(&bat->sdev->dev, "power event (cid = %#04x, iid = %#04x, tid = %#04x)\n",
+ event->command_id, event->instance_id, event->target_id);
+
+ switch (event->command_id) {
+ case SAM_EVENT_CID_BAT_BIX:
+ status = spwr_battery_recheck_full(bat);
+ break;
+
+ case SAM_EVENT_CID_BAT_BST:
+ status = spwr_battery_recheck_status(bat);
+ break;
+
+ case SAM_EVENT_CID_BAT_PROT:
+ /*
+ * TODO: Implement support for battery protection status change
+ * event.
+ */
+ status = 0;
+ break;
+
+ case SAM_EVENT_CID_BAT_DPTF:
+ /*
+ * TODO: Implement support for DPTF event.
+ */
+ status = 0;
+ break;
+
+ default:
+ return 0;
+ }
+
+ return ssam_notifier_from_errno(status) | SSAM_NOTIF_HANDLED;
+}
+
+static void spwr_battery_update_bst_workfn(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct spwr_battery_device *bat;
+ int status;
+
+ bat = container_of(dwork, struct spwr_battery_device, update_work);
+
+ status = spwr_battery_update_bst(bat, false);
+ if (status) {
+ dev_err(&bat->sdev->dev, "failed to update battery state: %d\n", status);
+ return;
+ }
+
+ power_supply_changed(bat->psy);
+}
+
+static void spwr_external_power_changed(struct power_supply *psy)
+{
+ struct spwr_battery_device *bat = power_supply_get_drvdata(psy);
+
+ /*
+ * Handle battery update quirk: When the battery is fully charged (or
+ * charged up to the limit imposed by the UEFI battery limit) and the
+ * adapter is plugged in or removed, the EC does not send a separate
+ * event for the state (charging/discharging) change. Furthermore it
+ * may take some time until the state is updated on the battery.
+ * Schedule an update to solve this.
+ */
+
+ schedule_delayed_work(&bat->update_work, SPWR_AC_BAT_UPDATE_DELAY);
+}
+
+
+/* -- Properties. ----------------------------------------------------------- */
+
+static const enum power_supply_property spwr_battery_props_chg[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_CYCLE_COUNT,
+ POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+ POWER_SUPPLY_PROP_CHARGE_FULL,
+ POWER_SUPPLY_PROP_CHARGE_NOW,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+ POWER_SUPPLY_PROP_MODEL_NAME,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+ POWER_SUPPLY_PROP_SERIAL_NUMBER,
+};
+
+static const enum power_supply_property spwr_battery_props_eng[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_CYCLE_COUNT,
+ POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_POWER_NOW,
+ POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
+ POWER_SUPPLY_PROP_ENERGY_FULL,
+ POWER_SUPPLY_PROP_ENERGY_NOW,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+ POWER_SUPPLY_PROP_MODEL_NAME,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+ POWER_SUPPLY_PROP_SERIAL_NUMBER,
+};
+
+static int spwr_battery_prop_status(struct spwr_battery_device *bat)
+{
+ u32 state = get_unaligned_le32(&bat->bst.state);
+ u32 present_rate = get_unaligned_le32(&bat->bst.present_rate);
+
+ lockdep_assert_held(&bat->lock);
+
+ if (state & SAM_BATTERY_STATE_DISCHARGING)
+ return POWER_SUPPLY_STATUS_DISCHARGING;
+
+ if (state & SAM_BATTERY_STATE_CHARGING)
+ return POWER_SUPPLY_STATUS_CHARGING;
+
+ if (spwr_battery_is_full(bat))
+ return POWER_SUPPLY_STATUS_FULL;
+
+ if (present_rate == 0)
+ return POWER_SUPPLY_STATUS_NOT_CHARGING;
+
+ return POWER_SUPPLY_STATUS_UNKNOWN;
+}
+
+static int spwr_battery_prop_technology(struct spwr_battery_device *bat)
+{
+ lockdep_assert_held(&bat->lock);
+
+ if (!strcasecmp("NiCd", bat->bix.type))
+ return POWER_SUPPLY_TECHNOLOGY_NiCd;
+
+ if (!strcasecmp("NiMH", bat->bix.type))
+ return POWER_SUPPLY_TECHNOLOGY_NiMH;
+
+ if (!strcasecmp("LION", bat->bix.type))
+ return POWER_SUPPLY_TECHNOLOGY_LION;
+
+ if (!strncasecmp("LI-ION", bat->bix.type, 6))
+ return POWER_SUPPLY_TECHNOLOGY_LION;
+
+ if (!strcasecmp("LiP", bat->bix.type))
+ return POWER_SUPPLY_TECHNOLOGY_LIPO;
+
+ return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
+}
+
+static int spwr_battery_prop_capacity(struct spwr_battery_device *bat)
+{
+ u32 full_cap = sprw_battery_get_full_cap_safe(bat);
+ u32 remaining_cap = get_unaligned_le32(&bat->bst.remaining_cap);
+
+ lockdep_assert_held(&bat->lock);
+
+ if (full_cap == 0 || full_cap == SPWR_BATTERY_VALUE_UNKNOWN)
+ return -ENODATA;
+
+ if (remaining_cap == SPWR_BATTERY_VALUE_UNKNOWN)
+ return -ENODATA;
+
+ return remaining_cap * 100 / full_cap;
+}
+
+static int spwr_battery_prop_capacity_level(struct spwr_battery_device *bat)
+{
+ u32 state = get_unaligned_le32(&bat->bst.state);
+ u32 remaining_cap = get_unaligned_le32(&bat->bst.remaining_cap);
+
+ lockdep_assert_held(&bat->lock);
+
+ if (state & SAM_BATTERY_STATE_CRITICAL)
+ return POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+
+ if (spwr_battery_is_full(bat))
+ return POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+
+ if (remaining_cap <= bat->alarm)
+ return POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+
+ return POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+}
+
+static int spwr_battery_get_property(struct power_supply *psy, enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct spwr_battery_device *bat = power_supply_get_drvdata(psy);
+ u32 value;
+ int status;
+
+ mutex_lock(&bat->lock);
+
+ status = spwr_battery_update_bst_unlocked(bat, true);
+ if (status)
+ goto out;
+
+ /* Abort if battery is not present. */
+ if (!spwr_battery_present(bat) && psp != POWER_SUPPLY_PROP_PRESENT) {
+ status = -ENODEV;
+ goto out;
+ }
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = spwr_battery_prop_status(bat);
+ break;
+
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = spwr_battery_present(bat);
+ break;
+
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = spwr_battery_prop_technology(bat);
+ break;
+
+ case POWER_SUPPLY_PROP_CYCLE_COUNT:
+ value = get_unaligned_le32(&bat->bix.cycle_count);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
+ value = get_unaligned_le32(&bat->bix.design_voltage);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ value = get_unaligned_le32(&bat->bst.present_voltage);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ case POWER_SUPPLY_PROP_POWER_NOW:
+ value = get_unaligned_le32(&bat->bst.present_rate);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+ case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
+ value = get_unaligned_le32(&bat->bix.design_cap);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_CHARGE_FULL:
+ case POWER_SUPPLY_PROP_ENERGY_FULL:
+ value = get_unaligned_le32(&bat->bix.last_full_charge_cap);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_CHARGE_NOW:
+ case POWER_SUPPLY_PROP_ENERGY_NOW:
+ value = get_unaligned_le32(&bat->bst.remaining_cap);
+ if (value != SPWR_BATTERY_VALUE_UNKNOWN)
+ val->intval = value * 1000;
+ else
+ status = -ENODATA;
+ break;
+
+ case POWER_SUPPLY_PROP_CAPACITY:
+ val->intval = spwr_battery_prop_capacity(bat);
+ break;
+
+ case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+ val->intval = spwr_battery_prop_capacity_level(bat);
+ break;
+
+ case POWER_SUPPLY_PROP_MODEL_NAME:
+ val->strval = bat->bix.model;
+ break;
+
+ case POWER_SUPPLY_PROP_MANUFACTURER:
+ val->strval = bat->bix.oem_info;
+ break;
+
+ case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+ val->strval = bat->bix.serial;
+ break;
+
+ default:
+ status = -EINVAL;
+ break;
+ }
+
+out:
+ mutex_unlock(&bat->lock);
+ return status;
+}
+
+
+/* -- Alarm attribute. ------------------------------------------------------ */
+
+static ssize_t alarm_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct power_supply *psy = dev_get_drvdata(dev);
+ struct spwr_battery_device *bat = power_supply_get_drvdata(psy);
+ int status;
+
+ mutex_lock(&bat->lock);
+ status = sysfs_emit(buf, "%d\n", bat->alarm * 1000);
+ mutex_unlock(&bat->lock);
+
+ return status;
+}
+
+static ssize_t alarm_store(struct device *dev, struct device_attribute *attr, const char *buf,
+ size_t count)
+{
+ struct power_supply *psy = dev_get_drvdata(dev);
+ struct spwr_battery_device *bat = power_supply_get_drvdata(psy);
+ unsigned long value;
+ int status;
+
+ status = kstrtoul(buf, 0, &value);
+ if (status)
+ return status;
+
+ mutex_lock(&bat->lock);
+
+ if (!spwr_battery_present(bat)) {
+ mutex_unlock(&bat->lock);
+ return -ENODEV;
+ }
+
+ status = spwr_battery_set_alarm_unlocked(bat, value / 1000);
+ if (status) {
+ mutex_unlock(&bat->lock);
+ return status;
+ }
+
+ mutex_unlock(&bat->lock);
+ return count;
+}
+
+DEVICE_ATTR_RW(alarm);
+
+static struct attribute *spwr_battery_attrs[] = {
+ &dev_attr_alarm.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(spwr_battery);
+
+
+/* -- Device setup. --------------------------------------------------------- */
+
+static void spwr_battery_init(struct spwr_battery_device *bat, struct ssam_device *sdev,
+ struct ssam_event_registry registry, const char *name)
+{
+ mutex_init(&bat->lock);
+ strncpy(bat->name, name, ARRAY_SIZE(bat->name) - 1);
+
+ bat->sdev = sdev;
+
+ bat->notif.base.priority = 1;
+ bat->notif.base.fn = spwr_notify_bat;
+ bat->notif.event.reg = registry;
+ bat->notif.event.id.target_category = sdev->uid.category;
+ bat->notif.event.id.instance = 0;
+ bat->notif.event.mask = SSAM_EVENT_MASK_STRICT;
+ bat->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+ bat->psy_desc.name = bat->name;
+ bat->psy_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+ bat->psy_desc.get_property = spwr_battery_get_property;
+
+ INIT_DELAYED_WORK(&bat->update_work, spwr_battery_update_bst_workfn);
+}
+
+static int spwr_battery_register(struct spwr_battery_device *bat)
+{
+ struct power_supply_config psy_cfg = {};
+ __le32 sta;
+ int status;
+
+ /* Make sure the device is there and functioning properly. */
+ status = ssam_retry(ssam_bat_get_sta, bat->sdev, &sta);
+ if (status)
+ return status;
+
+ if ((le32_to_cpu(sta) & SAM_BATTERY_STA_OK) != SAM_BATTERY_STA_OK)
+ return -ENODEV;
+
+ /* Satisfy lockdep although we are in an exclusive context here. */
+ mutex_lock(&bat->lock);
+
+ status = spwr_battery_update_bix_unlocked(bat);
+ if (status) {
+ mutex_unlock(&bat->lock);
+ return status;
+ }
+
+ if (spwr_battery_present(bat)) {
+ u32 cap_warn = get_unaligned_le32(&bat->bix.design_cap_warn);
+
+ status = spwr_battery_set_alarm_unlocked(bat, cap_warn);
+ if (status) {
+ mutex_unlock(&bat->lock);
+ return status;
+ }
+ }
+
+ mutex_unlock(&bat->lock);
+
+ bat->psy_desc.external_power_changed = spwr_external_power_changed;
+
+ switch (get_unaligned_le32(&bat->bix.power_unit)) {
+ case SAM_BATTERY_POWER_UNIT_mW:
+ bat->psy_desc.properties = spwr_battery_props_eng;
+ bat->psy_desc.num_properties = ARRAY_SIZE(spwr_battery_props_eng);
+ break;
+
+ case SAM_BATTERY_POWER_UNIT_mA:
+ bat->psy_desc.properties = spwr_battery_props_chg;
+ bat->psy_desc.num_properties = ARRAY_SIZE(spwr_battery_props_chg);
+ break;
+
+ default:
+ dev_err(&bat->sdev->dev, "unsupported battery power unit: %u\n",
+ get_unaligned_le32(&bat->bix.power_unit));
+ return -EINVAL;
+ }
+
+ psy_cfg.drv_data = bat;
+ psy_cfg.attr_grp = spwr_battery_groups;
+
+ bat->psy = devm_power_supply_register(&bat->sdev->dev, &bat->psy_desc, &psy_cfg);
+ if (IS_ERR(bat->psy))
+ return PTR_ERR(bat->psy);
+
+ return ssam_notifier_register(bat->sdev->ctrl, &bat->notif);
+}
+
+
+/* -- Driver setup. --------------------------------------------------------- */
+
+static int __maybe_unused surface_battery_resume(struct device *dev)
+{
+ return spwr_battery_recheck_full(dev_get_drvdata(dev));
+}
+SIMPLE_DEV_PM_OPS(surface_battery_pm_ops, NULL, surface_battery_resume);
+
+static int surface_battery_probe(struct ssam_device *sdev)
+{
+ const struct spwr_psy_properties *p;
+ struct spwr_battery_device *bat;
+
+ p = ssam_device_get_match_data(sdev);
+ if (!p)
+ return -ENODEV;
+
+ bat = devm_kzalloc(&sdev->dev, sizeof(*bat), GFP_KERNEL);
+ if (!bat)
+ return -ENOMEM;
+
+ spwr_battery_init(bat, sdev, p->registry, p->name);
+ ssam_device_set_drvdata(sdev, bat);
+
+ return spwr_battery_register(bat);
+}
+
+static void surface_battery_remove(struct ssam_device *sdev)
+{
+ struct spwr_battery_device *bat = ssam_device_get_drvdata(sdev);
+
+ ssam_notifier_unregister(sdev->ctrl, &bat->notif);
+ cancel_delayed_work_sync(&bat->update_work);
+}
+
+static const struct spwr_psy_properties spwr_psy_props_bat1 = {
+ .name = "BAT1",
+ .registry = SSAM_EVENT_REGISTRY_SAM,
+};
+
+static const struct spwr_psy_properties spwr_psy_props_bat2_sb3 = {
+ .name = "BAT2",
+ .registry = SSAM_EVENT_REGISTRY_KIP,
+};
+
+static const struct ssam_device_id surface_battery_match[] = {
+ { SSAM_SDEV(BAT, 0x01, 0x01, 0x00), (unsigned long)&spwr_psy_props_bat1 },
+ { SSAM_SDEV(BAT, 0x02, 0x01, 0x00), (unsigned long)&spwr_psy_props_bat2_sb3 },
+ { },
+};
+MODULE_DEVICE_TABLE(ssam, surface_battery_match);
+
+static struct ssam_device_driver surface_battery_driver = {
+ .probe = surface_battery_probe,
+ .remove = surface_battery_remove,
+ .match_table = surface_battery_match,
+ .driver = {
+ .name = "surface_battery",
+ .pm = &surface_battery_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_ssam_device_driver(surface_battery_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Battery driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
--
2.31.1
From 4e25091e5ce472d91a7786010a1a00f4ed1a0374 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 6 Apr 2021 01:41:26 +0200
Subject: [PATCH] power: supply: Add AC driver for Surface Aggregator Module
On newer Microsoft Surface models (specifically 7th-generation, i.e.
Surface Pro 7, Surface Book 3, Surface Laptop 3, and Surface Laptop Go),
battery and AC status/information is no longer handled via standard ACPI
devices, but instead directly via the Surface System Aggregator Module
(SSAM), i.e. the embedded controller on those devices.
While on previous generation models, AC status is also handled via SSAM,
an ACPI shim was present to translate the standard ACPI AC interface to
SSAM requests. The SSAM interface itself, which is modeled closely after
the ACPI interface, has not changed.
This commit introduces a new SSAM client device driver to support AC
status/information via the aforementioned interface on said Surface
models.
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Patchset: surface-sam
---
MAINTAINERS | 1 +
drivers/power/supply/Kconfig | 16 ++
drivers/power/supply/Makefile | 1 +
drivers/power/supply/surface_charger.c | 282 +++++++++++++++++++++++++
4 files changed, 300 insertions(+)
create mode 100644 drivers/power/supply/surface_charger.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7ee93b732270..710617e26f3e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11874,6 +11874,7 @@ L: linux-pm@vger.kernel.org
L: platform-driver-x86@vger.kernel.org
S: Maintained
F: drivers/power/supply/surface_battery.c
+F: drivers/power/supply/surface_charger.c
MICROSOFT SURFACE DTX DRIVER
M: Maximilian Luz <luzmaximilian@gmail.com>
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index cebeff10d543..91f7cf425ac9 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -817,4 +817,20 @@ config BATTERY_SURFACE
Microsoft Surface devices, i.e. Surface Pro 7, Surface Laptop 3,
Surface Book 3, and Surface Laptop Go.
+config CHARGER_SURFACE
+ tristate "AC driver for 7th-generation Microsoft Surface devices"
+ depends on SURFACE_AGGREGATOR_REGISTRY
+ help
+ Driver for AC devices connected via/managed by the Surface System
+ Aggregator Module (SSAM).
+
+ This driver provides AC-information and -status support for Surface
+ devices where said data is not exposed via the standard ACPI devices.
+ On those models (7th-generation), AC-information is instead handled
+ directly via a SSAM client device and this driver.
+
+ Say M or Y here to include AC status support for 7th-generation
+ Microsoft Surface devices, i.e. Surface Pro 7, Surface Laptop 3,
+ Surface Book 3, and Surface Laptop Go.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 134041538d2c..a7309a3d1a47 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -102,3 +102,4 @@ obj-$(CONFIG_CHARGER_WILCO) += wilco-charger.o
obj-$(CONFIG_RN5T618_POWER) += rn5t618_power.o
obj-$(CONFIG_BATTERY_ACER_A500) += acer_a500_battery.o
obj-$(CONFIG_BATTERY_SURFACE) += surface_battery.o
+obj-$(CONFIG_CHARGER_SURFACE) += surface_charger.o
diff --git a/drivers/power/supply/surface_charger.c b/drivers/power/supply/surface_charger.c
new file mode 100644
index 000000000000..c2dd7e604d14
--- /dev/null
+++ b/drivers/power/supply/surface_charger.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AC driver for 7th-generation Microsoft Surface devices via Surface System
+ * Aggregator Module (SSAM).
+ *
+ * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/power_supply.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/device.h>
+
+
+/* -- SAM interface. -------------------------------------------------------- */
+
+enum sam_event_cid_bat {
+ SAM_EVENT_CID_BAT_ADP = 0x17,
+};
+
+enum sam_battery_sta {
+ SAM_BATTERY_STA_OK = 0x0f,
+ SAM_BATTERY_STA_PRESENT = 0x10,
+};
+
+/* Get battery status (_STA). */
+SSAM_DEFINE_SYNC_REQUEST_CL_R(ssam_bat_get_sta, __le32, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x01,
+});
+
+/* Get platform power source for battery (_PSR / DPTF PSRC). */
+SSAM_DEFINE_SYNC_REQUEST_CL_R(ssam_bat_get_psrc, __le32, {
+ .target_category = SSAM_SSH_TC_BAT,
+ .command_id = 0x0d,
+});
+
+
+/* -- Device structures. ---------------------------------------------------- */
+
+struct spwr_psy_properties {
+ const char *name;
+ struct ssam_event_registry registry;
+};
+
+struct spwr_ac_device {
+ struct ssam_device *sdev;
+
+ char name[32];
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+
+ struct ssam_event_notifier notif;
+
+ struct mutex lock; /* Guards access to state below. */
+
+ __le32 state;
+};
+
+
+/* -- State management. ----------------------------------------------------- */
+
+static int spwr_ac_update_unlocked(struct spwr_ac_device *ac)
+{
+ u32 old = ac->state;
+ int status;
+
+ lockdep_assert_held(&ac->lock);
+
+ status = ssam_retry(ssam_bat_get_psrc, ac->sdev, &ac->state);
+ if (status < 0)
+ return status;
+
+ return old != ac->state;
+}
+
+static int spwr_ac_update(struct spwr_ac_device *ac)
+{
+ int status;
+
+ mutex_lock(&ac->lock);
+ status = spwr_ac_update_unlocked(ac);
+ mutex_unlock(&ac->lock);
+
+ return status;
+}
+
+static int spwr_ac_recheck(struct spwr_ac_device *ac)
+{
+ int status;
+
+ status = spwr_ac_update(ac);
+ if (status > 0)
+ power_supply_changed(ac->psy);
+
+ return status >= 0 ? 0 : status;
+}
+
+static u32 spwr_notify_ac(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+ struct spwr_ac_device *ac;
+ int status;
+
+ ac = container_of(nf, struct spwr_ac_device, notif);
+
+ dev_dbg(&ac->sdev->dev, "power event (cid = %#04x, iid = %#04x, tid = %#04x)\n",
+ event->command_id, event->instance_id, event->target_id);
+
+ /*
+ * Allow events of all targets/instances here. Global adapter status
+ * seems to be handled via target=1 and instance=1, but events are
+ * reported on all targets/instances in use.
+ *
+ * While it should be enough to just listen on 1/1, listen everywhere to
+ * make sure we don't miss anything.
+ */
+
+ switch (event->command_id) {
+ case SAM_EVENT_CID_BAT_ADP:
+ status = spwr_ac_recheck(ac);
+ return ssam_notifier_from_errno(status) | SSAM_NOTIF_HANDLED;
+
+ default:
+ return 0;
+ }
+}
+
+
+/* -- Properties. ----------------------------------------------------------- */
+
+static const enum power_supply_property spwr_ac_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+};
+
+static int spwr_ac_get_property(struct power_supply *psy, enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct spwr_ac_device *ac = power_supply_get_drvdata(psy);
+ int status;
+
+ mutex_lock(&ac->lock);
+
+ status = spwr_ac_update_unlocked(ac);
+ if (status)
+ goto out;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = !!le32_to_cpu(ac->state);
+ break;
+
+ default:
+ status = -EINVAL;
+ goto out;
+ }
+
+out:
+ mutex_unlock(&ac->lock);
+ return status;
+}
+
+
+/* -- Device setup. --------------------------------------------------------- */
+
+static char *battery_supplied_to[] = {
+ "BAT1",
+ "BAT2",
+};
+
+static void spwr_ac_init(struct spwr_ac_device *ac, struct ssam_device *sdev,
+ struct ssam_event_registry registry, const char *name)
+{
+ mutex_init(&ac->lock);
+ strncpy(ac->name, name, ARRAY_SIZE(ac->name) - 1);
+
+ ac->sdev = sdev;
+
+ ac->notif.base.priority = 1;
+ ac->notif.base.fn = spwr_notify_ac;
+ ac->notif.event.reg = registry;
+ ac->notif.event.id.target_category = sdev->uid.category;
+ ac->notif.event.id.instance = 0;
+ ac->notif.event.mask = SSAM_EVENT_MASK_NONE;
+ ac->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+ ac->psy_desc.name = ac->name;
+ ac->psy_desc.type = POWER_SUPPLY_TYPE_MAINS;
+ ac->psy_desc.properties = spwr_ac_props;
+ ac->psy_desc.num_properties = ARRAY_SIZE(spwr_ac_props);
+ ac->psy_desc.get_property = spwr_ac_get_property;
+}
+
+static int spwr_ac_register(struct spwr_ac_device *ac)
+{
+ struct power_supply_config psy_cfg = {};
+ __le32 sta;
+ int status;
+
+ /* Make sure the device is there and functioning properly. */
+ status = ssam_retry(ssam_bat_get_sta, ac->sdev, &sta);
+ if (status)
+ return status;
+
+ if ((le32_to_cpu(sta) & SAM_BATTERY_STA_OK) != SAM_BATTERY_STA_OK)
+ return -ENODEV;
+
+ psy_cfg.drv_data = ac;
+ psy_cfg.supplied_to = battery_supplied_to;
+ psy_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
+
+ ac->psy = devm_power_supply_register(&ac->sdev->dev, &ac->psy_desc, &psy_cfg);
+ if (IS_ERR(ac->psy))
+ return PTR_ERR(ac->psy);
+
+ return ssam_notifier_register(ac->sdev->ctrl, &ac->notif);
+}
+
+
+/* -- Driver setup. --------------------------------------------------------- */
+
+static int __maybe_unused surface_ac_resume(struct device *dev)
+{
+ return spwr_ac_recheck(dev_get_drvdata(dev));
+}
+SIMPLE_DEV_PM_OPS(surface_ac_pm_ops, NULL, surface_ac_resume);
+
+static int surface_ac_probe(struct ssam_device *sdev)
+{
+ const struct spwr_psy_properties *p;
+ struct spwr_ac_device *ac;
+
+ p = ssam_device_get_match_data(sdev);
+ if (!p)
+ return -ENODEV;
+
+ ac = devm_kzalloc(&sdev->dev, sizeof(*ac), GFP_KERNEL);
+ if (!ac)
+ return -ENOMEM;
+
+ spwr_ac_init(ac, sdev, p->registry, p->name);
+ ssam_device_set_drvdata(sdev, ac);
+
+ return spwr_ac_register(ac);
+}
+
+static void surface_ac_remove(struct ssam_device *sdev)
+{
+ struct spwr_ac_device *ac = ssam_device_get_drvdata(sdev);
+
+ ssam_notifier_unregister(sdev->ctrl, &ac->notif);
+}
+
+static const struct spwr_psy_properties spwr_psy_props_adp1 = {
+ .name = "ADP1",
+ .registry = SSAM_EVENT_REGISTRY_SAM,
+};
+
+static const struct ssam_device_id surface_ac_match[] = {
+ { SSAM_SDEV(BAT, 0x01, 0x01, 0x01), (unsigned long)&spwr_psy_props_adp1 },
+ { },
+};
+MODULE_DEVICE_TABLE(ssam, surface_ac_match);
+
+static struct ssam_device_driver surface_ac_driver = {
+ .probe = surface_ac_probe,
+ .remove = surface_ac_remove,
+ .match_table = surface_ac_match,
+ .driver = {
+ .name = "surface_ac",
+ .pm = &surface_ac_pm_ops,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+};
+module_ssam_device_driver(surface_ac_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("AC driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
--
2.31.1
From 7feb809859bd62d4a0b10e7d0ce3bdfee5e51d16 Mon Sep 17 00:00:00 2001
From: Qiheng Lin <linqiheng@huawei.com>
Date: Sat, 10 Apr 2021 12:12:46 +0800
Subject: [PATCH] power: supply: surface-battery: Make some symbols static
The sparse tool complains as follows:
drivers/power/supply/surface_battery.c:700:1: warning:
symbol 'dev_attr_alarm' was not declared. Should it be static?
drivers/power/supply/surface_battery.c:805:1: warning:
symbol 'surface_battery_pm_ops' was not declared. Should it be static?
This symbol is not used outside of surface_battery.c, so this
commit marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qiheng Lin <linqiheng@huawei.com>
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Patchset: surface-sam
---
drivers/power/supply/surface_battery.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/power/supply/surface_battery.c b/drivers/power/supply/surface_battery.c
index 4116dd839ecd..7efa431a62b2 100644
--- a/drivers/power/supply/surface_battery.c
+++ b/drivers/power/supply/surface_battery.c
@@ -697,7 +697,7 @@ static ssize_t alarm_store(struct device *dev, struct device_attribute *attr, co
return count;
}
-DEVICE_ATTR_RW(alarm);
+static DEVICE_ATTR_RW(alarm);
static struct attribute *spwr_battery_attrs[] = {
&dev_attr_alarm.attr,
@@ -802,7 +802,7 @@ static int __maybe_unused surface_battery_resume(struct device *dev)
{
return spwr_battery_recheck_full(dev_get_drvdata(dev));
}
-SIMPLE_DEV_PM_OPS(surface_battery_pm_ops, NULL, surface_battery_resume);
+static SIMPLE_DEV_PM_OPS(surface_battery_pm_ops, NULL, surface_battery_resume);
static int surface_battery_probe(struct ssam_device *sdev)
{
--
2.31.1
From 1602265bbdfcc8368d48c3aa664e5b52fcea88da Mon Sep 17 00:00:00 2001
From: Qiheng Lin <linqiheng@huawei.com>
Date: Sat, 10 Apr 2021 12:12:49 +0800
Subject: [PATCH] power: supply: surface-charger: Make symbol
'surface_ac_pm_ops' static
The sparse tool complains as follows:
drivers/power/supply/surface_charger.c:229:1: warning:
symbol 'surface_ac_pm_ops' was not declared. Should it be static?
This symbol is not used outside of surface_charger.c, so this
commit marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qiheng Lin <linqiheng@huawei.com>
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Patchset: surface-sam
---
drivers/power/supply/surface_charger.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/power/supply/surface_charger.c b/drivers/power/supply/surface_charger.c
index c2dd7e604d14..81a5b79822c9 100644
--- a/drivers/power/supply/surface_charger.c
+++ b/drivers/power/supply/surface_charger.c
@@ -226,7 +226,7 @@ static int __maybe_unused surface_ac_resume(struct device *dev)
{
return spwr_ac_recheck(dev_get_drvdata(dev));
}
-SIMPLE_DEV_PM_OPS(surface_ac_pm_ops, NULL, surface_ac_resume);
+static SIMPLE_DEV_PM_OPS(surface_ac_pm_ops, NULL, surface_ac_resume);
static int surface_ac_probe(struct ssam_device *sdev)
{
--
2.31.1
From 729ee99a1b2b0586c5699f96c0ad55926322c4a6 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 4 May 2021 20:00:46 +0200
Subject: [PATCH] power: supply: surface_battery: Fix battery event handling
The battery subsystem of the Surface Aggregator Module EC requires us to
register the battery notifier with instance ID 0. However, battery
events are actually sent with the instance ID corresponding to the
device, which is nonzero. Thus, the strict-matching approach doesn't
work here and will discard events that the driver is expected to handle.
To fix this we have to fall back on notifier matching by target-category
only and have to manually check the instance ID in the notifier
callback.
Fixes: 167f77f7d0b3 ("power: supply: Add battery driver for Surface Aggregator Module")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/power/supply/surface_battery.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/power/supply/surface_battery.c b/drivers/power/supply/surface_battery.c
index 7efa431a62b2..5ec2e6bb2465 100644
--- a/drivers/power/supply/surface_battery.c
+++ b/drivers/power/supply/surface_battery.c
@@ -345,6 +345,16 @@ static u32 spwr_notify_bat(struct ssam_event_notifier *nf, const struct ssam_eve
struct spwr_battery_device *bat = container_of(nf, struct spwr_battery_device, notif);
int status;
+ /*
+ * We cannot use strict matching when registering the notifier as the
+ * EC expects us to register it against instance ID 0. Strict matching
+ * would thus drop events, as those may have non-zero instance IDs in
+ * this subsystem. So we need to check the instance ID of the event
+ * here manually.
+ */
+ if (event->instance_id != bat->sdev->uid.instance)
+ return 0;
+
dev_dbg(&bat->sdev->dev, "power event (cid = %#04x, iid = %#04x, tid = %#04x)\n",
event->command_id, event->instance_id, event->target_id);
@@ -720,8 +730,8 @@ static void spwr_battery_init(struct spwr_battery_device *bat, struct ssam_devic
bat->notif.base.fn = spwr_notify_bat;
bat->notif.event.reg = registry;
bat->notif.event.id.target_category = sdev->uid.category;
- bat->notif.event.id.instance = 0;
- bat->notif.event.mask = SSAM_EVENT_MASK_STRICT;
+ bat->notif.event.id.instance = 0; /* need to register with instance 0 */
+ bat->notif.event.mask = SSAM_EVENT_MASK_TARGET;
bat->notif.event.flags = SSAM_EVENT_SEQUENCED;
bat->psy_desc.name = bat->name;
--
2.31.1
From 36347fcfa36a6d6bfa89d75545c73d44704cf4db Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 11 May 2021 11:24:21 +0200
Subject: [PATCH] power: supply: surface-charger: Fix type of integer variable
The ac->state field is __le32, not u32. So change the variable we're
temporarily storing it in to __le32 as well.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: e61ffb344591 ("power: supply: Add AC driver for Surface Aggregator Module")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/power/supply/surface_charger.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/power/supply/surface_charger.c b/drivers/power/supply/surface_charger.c
index 81a5b79822c9..a060c36c7766 100644
--- a/drivers/power/supply/surface_charger.c
+++ b/drivers/power/supply/surface_charger.c
@@ -66,7 +66,7 @@ struct spwr_ac_device {
static int spwr_ac_update_unlocked(struct spwr_ac_device *ac)
{
- u32 old = ac->state;
+ __le32 old = ac->state;
int status;
lockdep_assert_held(&ac->lock);
--
2.31.1
From 8a75f61f824d460381dde994c806f233ddccfd58 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Wed, 5 May 2021 18:17:04 +0200
Subject: [PATCH] serial: 8250_dw: Add device HID for new AMD UART controller
Add device HID AMDI0022 to the AMD UART controller driver match table
and create a platform device for it. This controller can be found on
Microsoft Surface Laptop 4 devices and seems similar enough that we can
just copy the existing AMDI0020 entries.
Cc: <stable@vger.kernel.org> # 5.10+
Tested-by: Sachi King <nakato@nakato.io>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/acpi/acpi_apd.c | 1 +
drivers/tty/serial/8250/8250_dw.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
index 39359ce0eb2c..645e82a66bb0 100644
--- a/drivers/acpi/acpi_apd.c
+++ b/drivers/acpi/acpi_apd.c
@@ -226,6 +226,7 @@ static const struct acpi_device_id acpi_apd_device_ids[] = {
{ "AMDI0010", APD_ADDR(wt_i2c_desc) },
{ "AMD0020", APD_ADDR(cz_uart_desc) },
{ "AMDI0020", APD_ADDR(cz_uart_desc) },
+ { "AMDI0022", APD_ADDR(cz_uart_desc) },
{ "AMD0030", },
{ "AMD0040", APD_ADDR(fch_misc_desc)},
{ "HYGO0010", APD_ADDR(wt_i2c_desc) },
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 9e204f9b799a..a3a0154da567 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -714,6 +714,7 @@ static const struct acpi_device_id dw8250_acpi_match[] = {
{ "APMC0D08", 0},
{ "AMD0020", 0 },
{ "AMDI0020", 0 },
+ { "AMDI0022", 0 },
{ "BRCM2032", 0 },
{ "HISI0031", 0 },
{ },
--
2.31.1
From eebad61f66d0119629269d1d3eb2339f9e371192 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Wed, 5 May 2021 18:22:04 +0200
Subject: [PATCH] pinctrl/amd: Add device HID for new AMD GPIO controller
Add device HID AMDI0031 to the AMD GPIO controller driver match table.
This controller can be found on Microsoft Surface Laptop 4 devices and
seems similar enough that we can just copy the existing AMDI0030 entry.
Cc: <stable@vger.kernel.org> # 5.10+
Tested-by: Sachi King <nakato@nakato.io>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
drivers/pinctrl/pinctrl-amd.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index 2d4acf21117c..c5950a3b4e4c 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -991,6 +991,7 @@ static int amd_gpio_remove(struct platform_device *pdev)
static const struct acpi_device_id amd_gpio_acpi_match[] = {
{ "AMD0030", 0 },
{ "AMDI0030", 0},
+ { "AMDI0031", 0},
{ },
};
MODULE_DEVICE_TABLE(acpi, amd_gpio_acpi_match);
--
2.31.1
From 1bfc4a7ec82c4c2e25f568cf1b14b071bd5737c3 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Mon, 10 May 2021 23:33:17 +0200
Subject: [PATCH] x86/i8259: Work around buggy legacy PIC
The legacy PIC on the AMD variant of the Microsoft Surface Laptop 4 has
some problems on boot. For some reason it consistently does not respond
on the first try, requiring a couple more tries before it finally
responds.
This currently leads to the PIC not being properly recognized, which
prevents interrupt handling down the line. Ultimately, this also leads
to the pinctrl-amd driver failing to probe due to platform_get_irq()
returning -EINVAL for its base IRQ. That, in turn, means that several
interrupts are not available and device drivers relying on those will
defer probing indefinitely, as querying those interrupts returns
-EPROBE_DEFER.
Add a quirk table and a retry-loop to work around that.
Also switch to pr_info() due to complaints by checkpatch and add a
pr_fmt() definition for completeness.
Cc: <stable@vger.kernel.org> # 5.10+
Co-developed-by: Sachi King <nakato@nakato.io>
Signed-off-by: Sachi King <nakato@nakato.io>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
arch/x86/kernel/i8259.c | 51 +++++++++++++++++++++++++++++++++++++----
1 file changed, 46 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c
index 282b4ee1339f..0da757c6b292 100644
--- a/arch/x86/kernel/i8259.c
+++ b/arch/x86/kernel/i8259.c
@@ -1,4 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
+
+#define pr_fmt(fmt) "i8259: " fmt
+
#include <linux/linkage.h>
#include <linux/errno.h>
#include <linux/signal.h>
@@ -16,6 +19,7 @@
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/pgtable.h>
+#include <linux/dmi.h>
#include <linux/atomic.h>
#include <asm/timer.h>
@@ -298,11 +302,39 @@ static void unmask_8259A(void)
raw_spin_unlock_irqrestore(&i8259A_lock, flags);
}
+/*
+ * DMI table to identify devices with quirky probe behavior. See comment in
+ * probe_8259A() for more details.
+ */
+static const struct dmi_system_id retry_probe_quirk_table[] = {
+ {
+ .ident = "Microsoft Surface Laptop 4 (AMD)",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
+ DMI_MATCH(DMI_PRODUCT_SKU, "Surface_Laptop_4_1952:1953")
+ },
+ },
+ {}
+};
+
static int probe_8259A(void)
{
unsigned long flags;
unsigned char probe_val = ~(1 << PIC_CASCADE_IR);
unsigned char new_val;
+ unsigned int i, imax = 1;
+
+ /*
+ * Some systems have a legacy PIC that doesn't immediately respond
+ * after boot. We know it's there, we know it should respond and is
+ * required for proper interrupt handling later on, so let's try a
+ * couple of times.
+ */
+ if (dmi_check_system(retry_probe_quirk_table)) {
+ pr_warn("system with broken legacy PIC detected, re-trying multiple times if necessary\n");
+ imax = 10;
+ }
+
/*
* Check to see if we have a PIC.
* Mask all except the cascade and read
@@ -312,15 +344,24 @@ static int probe_8259A(void)
*/
raw_spin_lock_irqsave(&i8259A_lock, flags);
- outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
- outb(probe_val, PIC_MASTER_IMR);
- new_val = inb(PIC_MASTER_IMR);
- if (new_val != probe_val) {
- printk(KERN_INFO "Using NULL legacy PIC\n");
+ for (i = 0; i < imax; i++) {
+ outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
+ outb(probe_val, PIC_MASTER_IMR);
+ new_val = inb(PIC_MASTER_IMR);
+ if (new_val == probe_val)
+ break;
+ }
+
+ if (i == imax) {
+ pr_info("using NULL legacy PIC\n");
legacy_pic = &null_legacy_pic;
}
raw_spin_unlock_irqrestore(&i8259A_lock, flags);
+
+ if (imax > 1 && i < imax)
+ pr_info("got legacy PIC after %d tries\n", i + 1);
+
return nr_legacy_irqs();
}
--
2.31.1
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