# Maintainer: Maximilian Luz <luzmaximilian@gmail.com>

pkgbase=linux-surface-lts
pkgver=4.19.193
pkgrel=1
pkgdesc='LTS Linux'
url="https://www.kernel.org/"
arch=(x86_64)
license=(GPL2)
makedepends=(
  bc kmod libelf cpio perl tar xz
  python
  xmlto python-sphinx python-sphinx_rtd_theme graphviz imagemagick
)
options=('!strip')
_srcname=linux-$pkgver
source=(
  https://www.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/${_srcname}.tar.{xz,sign}
  config         # the main kernel config file
  0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch

  surface.config

  0001-surface3-power.patch
  0002-surface3-touchscreen-dma-fix.patch
  0003-surface3-oemb.patch
  0004-surface-buttons.patch
  0005-suspend.patch
  0006-ipts.patch
  0007-wifi.patch
  0008-surface-gpe.patch
  0009-surface-sam-over-hid.patch
  0010-surface-sam.patch
  0011-surface-hotplug.patch
  0012-surface-typecover.patch
  0013-surface-go-touchscreen.patch
  0014-ath10k-firmware-override.patch
)
validpgpkeys=(
  'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
  '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
)
# https://www.kernel.org/pub/linux/kernel/v4.x/sha256sums.asc
sha256sums=('84c2ea0b8d096bbb46eceb04825090a4c2f4987dcc0d3bdd0c80c7325522919d'
            'SKIP'
            '4e68572e7cc4c5368f0236e0792660ae8498373988625dca46e509399a7eaea6'
            'a13581d3c6dc595206e4fe7fcf6b542e7a1bdbe96101f0f010fc5be49f99baf2'
            'c523d8ba9f02992c34b325cd7b07e27bfead33ecab29877e659a12b2d56b1118'
            '1db89e197b05aafeab4257fd2610823137297d0f38761c5463f178903a81c730'
            '960788d1f8e59965e6e68dc3c83fad09edade041738c85c277ad3fbcc3f3b66f'
            '9e872762e8ab8513c8402864f124d0b34de348d625fe64193987c50b98770ae0'
            'bd8677d585cb2cbdd8138ed475b1c1744d5f7f3ca5d95274b90b9961be459278'
            'c22ec8bf62046a203a1c5d9e1e15425eef0933714d23d2e7f2e39023bf322a53'
            '2d3ba06a04e652722ce804bfbbd478e40bdc83ce0fe106b4f62cde169207ff51'
            'cfc277e4a36d50d815c274020a192ffc4cb77b67d7a54913c1259782d7f1d785'
            'f511907d1f1e6ca8a7e6a2f4d9e464f4378de1095f8618a3abfa4cc1ac194577'
            '8956b5be58f556064b5f29d149c7f2965c642c228faf828c4d7b09f93af44efa'
            '1e31bd2ad6953b09e9f9fddfced439e8ff126accd40fb0726e0d7a23be71d2a8'
            '5ae7331873642bb99f0b4bb0cf4c665f5ce73ec93ab21b75e6db460f9f946faf'
            '4c44ba127c6430db1f1d17d021216cccba738900a446e246a3b1c36702c23d20'
            '363f4bec0c02770b615efca07586de498b19a097d26c55ba8a2a22ea83512739'
            'fe6a9f042b3d991b40c0e7676babb2778fb6fc3d53a2e43b919c18d9a57a8c3b')

export KBUILD_BUILD_HOST=archlinux
export KBUILD_BUILD_USER=$pkgbase
export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

# optional certificate and key for secure boot signing
_mok_crt="$PWD/MOK.crt"
_mok_key="$PWD/MOK.key"

prepare() {
  cd $_srcname

  msg2 "Setting version..."
  scripts/setlocalversion --save-scmversion
  echo "-$pkgrel" > localversion.10-pkgrel
  echo "${pkgbase#linux}" > localversion.20-pkgname

  local src
  for src in "${source[@]}"; do
    src="${src%%::*}"
    src="${src##*/}"
    [[ $src = *.patch ]] || continue
    msg2 "Applying patch $src..."
    patch -Np1 < "../$src"
  done

  msg2 "Setting config..."
  # cp ../config .config
  # merge the two configs together
  ./scripts/kconfig/merge_config.sh -m ../config ../surface.config
  make olddefconfig

  make -s kernelrelease > version
  msg2 "Prepared %s version %s" "$pkgbase" "$(<version)"
}

build() {
  cd $_srcname
  make bzImage modules
}

_package() {
  pkgdesc="The $pkgdesc kernel and modules"
  depends=(coreutils kmod initramfs)
  optdepends=('crda: to set the correct wireless channels of your country'
              'linux-firmware: firmware images needed for some devices')
  provides=("linux=${pkgver}")

  cd $_srcname
  local kernver="$(<version)"
  local modulesdir="$pkgdir/usr/lib/modules/$kernver"
  local image_name="$(make -s image_name)"

  # sign boot image if the prequisites are available
  if [[ -f "$_mok_crt" ]] && [[ -f "$_mok_key" ]] && [[ -x "$(command -v sbsign)" ]]; then
    msg2 "Signing boot image..."
    sbsign --key "$_mok_key" --cert "$_mok_crt" --output "$image_name" "$image_name"
  fi

  msg2 "Installing boot image..."
  # systemd expects to find the kernel here to allow hibernation
  # https://github.com/systemd/systemd/commit/edda44605f06a41fb86b7ab8128dcf99161d2344
  install -Dm644 "$image_name" "$modulesdir/vmlinuz"

  # Used by mkinitcpio to name the kernel
  echo "$pkgbase" | install -Dm644 /dev/stdin "$modulesdir/pkgbase"

  msg2 "Installing modules..."
  make INSTALL_MOD_PATH="$pkgdir/usr" modules_install

  # remove build and source links
  rm "$modulesdir"/{source,build}

  msg2 "Fixing permissions..."
  chmod -Rc u=rwX,go=rX "$pkgdir"
}

_package-headers() {
  pkgdesc="Headers and scripts for building modules for the $pkgdesc kernel"
  provides=("linux-headers=${pkgver}")

  cd $_srcname
  local builddir="$pkgdir/usr/lib/modules/$(<version)/build"

  msg2 "Installing build files..."
  install -Dt "$builddir" -m644 .config Makefile Module.symvers System.map \
    localversion.* version vmlinux
  install -Dt "$builddir/kernel" -m644 kernel/Makefile
  install -Dt "$builddir/arch/x86" -m644 arch/x86/Makefile
  cp -t "$builddir" -a scripts

  # add objtool for external module building and enabled VALIDATION_STACK option
  install -Dt "$builddir/tools/objtool" tools/objtool/objtool

  # add xfs and shmem for aufs building
  mkdir -p "$builddir"/{fs/xfs,mm}

  # this is gone in v5.3
  mkdir "$builddir/.tmp_versions"

  msg2 "Installing headers..."
  cp -t "$builddir" -a include
  cp -t "$builddir/arch/x86" -a arch/x86/include
  install -Dt "$builddir/arch/x86/kernel" -m644 arch/x86/kernel/asm-offsets.s

  install -Dt "$builddir/drivers/md" -m644 drivers/md/*.h
  install -Dt "$builddir/net/mac80211" -m644 net/mac80211/*.h

  # http://bugs.archlinux.org/task/13146
  install -Dt "$builddir/drivers/media/i2c" -m644 drivers/media/i2c/msp3400-driver.h

  # http://bugs.archlinux.org/task/20402
  install -Dt "$builddir/drivers/media/usb/dvb-usb" -m644 drivers/media/usb/dvb-usb/*.h
  install -Dt "$builddir/drivers/media/dvb-frontends" -m644 drivers/media/dvb-frontends/*.h
  install -Dt "$builddir/drivers/media/tuners" -m644 drivers/media/tuners/*.h

  msg2 "Installing KConfig files..."
  find . -name 'Kconfig*' -exec install -Dm644 {} "$builddir/{}" \;

  msg2 "Removing unneeded architectures..."
  local arch
  for arch in "$builddir"/arch/*/; do
    [[ $arch = */x86/ ]] && continue
    echo "Removing $(basename "$arch")"
    rm -r "$arch"
  done

  msg2 "Removing documentation..."
  rm -r "$builddir/Documentation"

  msg2 "Removing broken symlinks..."
  find -L "$builddir" -type l -printf 'Removing %P\n' -delete

  msg2 "Removing loose objects..."
  find "$builddir" -type f -name '*.o' -printf 'Removing %P\n' -delete

  msg2 "Stripping build tools..."
  local file
  while read -rd '' file; do
    case "$(file -bi "$file")" in
      application/x-sharedlib\;*)      # Libraries (.so)
        strip -v $STRIP_SHARED "$file" ;;
      application/x-archive\;*)        # Libraries (.a)
        strip -v $STRIP_STATIC "$file" ;;
      application/x-executable\;*)     # Binaries
        strip -v $STRIP_BINARIES "$file" ;;
      application/x-pie-executable\;*) # Relocatable binaries
        strip -v $STRIP_SHARED "$file" ;;
    esac
  done < <(find "$builddir" -type f -perm -u+x ! -name vmlinux -print0)

  msg2 "Adding symlink..."
  mkdir -p "$pkgdir/usr/src"
  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"

  msg2 "Fixing permissions..."
  chmod -Rc u=rwX,go=rX "$pkgdir"
}

pkgname=("$pkgbase" "$pkgbase-headers")
for _p in "${pkgname[@]}"; do
  eval "package_$_p() {
    $(declare -f "_package${_p#$pkgbase}")
    _package${_p#$pkgbase}
  }"
done

# vim:set ts=8 sts=2 sw=2 et: