155 lines
4.9 KiB
Plaintext
155 lines
4.9 KiB
Plaintext
Davinci Video processing Front End (VPFE) driver
|
|
|
|
Copyright (C) 2012 Texas Instruments Inc
|
|
|
|
Contacts: Manjunath Hadli <manjunath.hadli@ti.com>
|
|
Prabhakar Lad <prabhakar.lad@ti.com>
|
|
|
|
|
|
Introduction
|
|
============
|
|
|
|
This file documents the Texas Instruments Davinci Video processing Front End
|
|
(VPFE) driver located under drivers/media/platform/davinci. The original driver
|
|
exists for Davinci VPFE, which is now being changed to Media Controller
|
|
Framework.
|
|
|
|
Currently the driver has been successfully used on the following
|
|
version of Davinci:
|
|
|
|
DM365/DM368
|
|
|
|
The driver implements V4L2, Media controller and v4l2_subdev interfaces. Sensor,
|
|
lens and flash drivers using the v4l2_subdev interface in the kernel are
|
|
supported.
|
|
|
|
|
|
Split to subdevs
|
|
================
|
|
|
|
The Davinci VPFE is split into V4L2 subdevs, each of the blocks inside the VPFE
|
|
having one subdev to represent it. Each of the subdevs provide a V4L2 subdev
|
|
interface to userspace.
|
|
|
|
DAVINCI ISIF
|
|
DAVINCI IPIPEIF
|
|
DAVINCI IPIPE
|
|
DAVINCI CROP RESIZER
|
|
DAVINCI RESIZER A
|
|
DAVINCI RESIZER B
|
|
|
|
Each possible link in the VPFE is modelled by a link in the Media controller
|
|
interface. For an example program see [1].
|
|
|
|
|
|
ISIF, IPIPE, and RESIZER block IOCTLs
|
|
======================================
|
|
|
|
The Davinci Video processing Front End (VPFE) driver supports standard V4L2
|
|
IOCTLs and controls where possible and practical. Much of the functions provided
|
|
by the VPFE, however, does not fall under the standard IOCTL's.
|
|
|
|
In general, there is a private ioctl for configuring each of the blocks
|
|
containing hardware-dependent functions.
|
|
|
|
The following private IOCTLs are supported:
|
|
|
|
VIDIOC_VPFE_ISIF_[S/G]_RAW_PARAMS
|
|
VIDIOC_VPFE_IPIPE_[S/G]_CONFIG
|
|
VIDIOC_VPFE_RSZ_[S/G]_CONFIG
|
|
|
|
The parameter structures used by these ioctl's are described in
|
|
include/uapi/linux/davinci_vpfe.h.
|
|
|
|
The VIDIOC_VPFE_ISIF_S_RAW_PARAMS, VIDIOC_VPFE_IPIPE_S_CONFIG and
|
|
VIDIOC_VPFE_RSZ_S_CONFIG are used to configure, enable and disable functions in
|
|
the isif, ipipe and resizer blocks respectively. These IOCTL's control several
|
|
functions in the blocks they control. VIDIOC_VPFE_ISIF_S_RAW_PARAMS IOCTL
|
|
accepts a pointer to struct vpfe_isif_raw_config as its argument. Similarly
|
|
VIDIOC_VPFE_IPIPE_S_CONFIG accepts a pointer to struct vpfe_ipipe_config. And
|
|
VIDIOC_VPFE_RSZ_S_CONFIG accepts a pointer to struct vpfe_rsz_config as its
|
|
argument. Similarly VIDIOC_VPFE_ISIF_G_RAW_PARAMS, VIDIOC_VPFE_IPIPE_G_CONFIG
|
|
and VIDIOC_VPFE_RSZ_G_CONFIG are used to get the current configuration set in
|
|
the isif, ipipe and resizer blocks respectively.
|
|
|
|
The detailed functions of the VPFE itself related to a given VPFE block is
|
|
described in the Technical Reference Manuals (TRMs) --- see the end of the
|
|
document for those.
|
|
|
|
|
|
IPIPEIF block IOCTLs
|
|
======================================
|
|
|
|
The following private IOCTLs are supported:
|
|
|
|
VIDIOC_VPFE_IPIPEIF_[S/G]_CONFIG
|
|
|
|
The parameter structures used by these ioctl's are described in
|
|
include/uapi/linux/dm365_ipipeif.h
|
|
|
|
The VIDIOC_VPFE_IPIPEIF_S_CONFIG is used to configure the ipipeif
|
|
hardware block. The VIDIOC_VPFE_IPIPEIF_S_CONFIG and
|
|
VIDIOC_VPFE_IPIPEIF_G_CONFIG accepts a pointer to struct ipipeif_params
|
|
as its argument.
|
|
|
|
|
|
VPFE Operating Modes
|
|
==========================================
|
|
|
|
a: Continuous Modes
|
|
------------------------
|
|
|
|
1: tvp514x/tvp7002/mt9p031---> DAVINCI ISIF---> SDRAM
|
|
|
|
2: tvp514x/tvp7002/mt9p031---> DAVINCI ISIF---> DAVINCI IPIPEIF--->|
|
|
|
|
|
<--------------------<----------------<---------------------<---|
|
|
|
|
|
V
|
|
DAVINCI CROP RESIZER--->DAVINCI RESIZER [A/B]---> SDRAM
|
|
|
|
3: tvp514x/tvp7002/mt9p031---> DAVINCI ISIF---> DAVINCI IPIPEIF--->|
|
|
|
|
|
<--------------------<----------------<---------------------<---|
|
|
|
|
|
V
|
|
DAVINCI IPIPE---> DAVINCI CROP RESIZER--->DAVINCI RESIZER [A/B]---> SDRAM
|
|
|
|
a: Single Shot Modes
|
|
------------------------
|
|
|
|
1: SDRAM---> DAVINCI IPIPEIF---> DAVINCI IPIPE---> DAVINCI CROP RESIZER--->|
|
|
|
|
|
<----------------<----------------<------------------<---------------<--|
|
|
|
|
|
V
|
|
DAVINCI RESIZER [A/B]---> SDRAM
|
|
|
|
2: SDRAM---> DAVINCI IPIPEIF---> DAVINCI CROP RESIZER--->|
|
|
|
|
|
<----------------<----------------<---------------<---|
|
|
|
|
|
V
|
|
DAVINCI RESIZER [A/B]---> SDRAM
|
|
|
|
|
|
Technical reference manuals (TRMs) and other documentation
|
|
==========================================================
|
|
|
|
Davinci DM365 TRM:
|
|
<URL:http://www.ti.com/lit/ds/sprs457e/sprs457e.pdf>
|
|
Referenced MARCH 2009-REVISED JUNE 2011
|
|
|
|
Davinci DM368 TRM:
|
|
<URL:http://www.ti.com/lit/ds/sprs668c/sprs668c.pdf>
|
|
Referenced APRIL 2010-REVISED JUNE 2011
|
|
|
|
Davinci Video Processing Front End (VPFE) DM36x
|
|
<URL:http://www.ti.com/lit/ug/sprufg8c/sprufg8c.pdf>
|
|
|
|
|
|
References
|
|
==========
|
|
|
|
[1] http://git.ideasonboard.org/?p=media-ctl.git;a=summary
|