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

pkgbase=linux-surface-lts
pkgver=4.19.186
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-ath10k-firmware-override.patch
)
validpgpkeys=(
  'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
  '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
)
# https://www.kernel.org/pub/linux/kernel/v4.x/sha256sums.asc
sha256sums=('d8c5d7844214510e85ceb9f5236f27f63fc03535a143f3aaa0c1677a8f92e631'
            'SKIP'
            '4e68572e7cc4c5368f0236e0792660ae8498373988625dca46e509399a7eaea6'
            'a13581d3c6dc595206e4fe7fcf6b542e7a1bdbe96101f0f010fc5be49f99baf2'
            'c523d8ba9f02992c34b325cd7b07e27bfead33ecab29877e659a12b2d56b1118'
            '28d0590c7d80c78a3241b3bc02f8f1c9740e29836e5219390b9bd2e74294d275'
            '714104ee77c2cbaa85ed898038b86187e4bcad55303c7fb53a289b118958e033'
            '71478881042d360c743806dfdbba8ece05d2c1ad9629d9d73cef60b5fd4d0f1b'
            'b5399a2c1bbb7355e7873445e1831d16c0de6d3f07fb6822f4998d68a1a35631'
            'ee37069a260b0cb5e478eb62471714faba516edbaa387637188e7ee1b2ae308a'
            'e7b55a844072a6929c71114cd2f411fb9d2b93bb5ac1190b97d82a7fcfadbe06'
            '53b6608d17a58c347ab1de8aaf030bf2ef153586c9f34799c34ca9142b001f5f'
            'bf64c846e8667aa09f17a0c3cdc54bb4f4c5bd5c37a6be88e514860771f9b956'
            '7ad639a41c5dce7c06fdad16c9ccb4a822f715a75ebca652a914f9b58cbae22a'
            '6f2d0ca2bef37961c6dedf6b2175dd0f738d9b5b79d4b8dc1921b3e157bf705f'
            '3868ec90be5782a5b291d8967a407aab4bdc3d84a85e1fc351e33d406c9e5c2d'
            'bfca8cd52316357a1ee3c0cc7892a3b27788e0d3a3e4145c71be8094b02f76a7'
            'af63dd5479626119df2dcb85b850c1111b8666f4292d1c74f123ad62fe6f687b')

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: