amazon-mustang: new device (MR 1263)

Just got done with my second port of postmarketOS, here's the device:
Amazon Fire 7 (2019) postmarketOS
Mediatek MT8163
600x1024 display
1GB RAM
Linux 4.9.77 (downstream kernel)

Untested:
- Wi-Fi
- Audio
Pretty much everything else

Works:
- Boots
- Touchscreen
- Battery percentage seems to show in Xfce

device/testing/device-amazon-mustang/APKBUILD

+# Reference: <https://postmarketos.org/devicepkg>
+pkgname=device-amazon-mustang
+pkgdesc="Amazon Fire 7 (2019)"
+pkgver=0.1
+pkgrel=0
+url="https://postmarketos.org"
+license="MIT"
+arch="armv7"
+options="!check !archcheck"
+depends="postmarketos-base linux-amazon-mustang mkbootimg mesa-dri-gallium"
+makedepends="devicepkg-dev"
+source="deviceinfo"
+
+build() {
+	devicepkg_build $startdir $pkgname
+}
+
+package() {
+	devicepkg_package $startdir $pkgname
+}
+
+sha512sums="9a1e225af66c34e6c9f2e7137e9904106bf7858ffc0fd370de16d1a4b2088c18d9138c3b20e8089d46773d50841aba8d8e915a8dd6c53b3584bcdf18ed3de3ed  deviceinfo"

device/testing/device-amazon-mustang/deviceinfo

+# Reference: <https://postmarketos.org/deviceinfo>
+# Please use double quotes only. You can source this file in shell scripts.
+
+deviceinfo_format_version="0"
+deviceinfo_name="Amazon Fire 7 (2019)"
+deviceinfo_manufacturer="Amazon"
+deviceinfo_codename="amazon-mustang"
+deviceinfo_year="2019"
+deviceinfo_dtb=""
+deviceinfo_modules_initfs=""
+deviceinfo_arch="armv7"
+
+# Device related
+deviceinfo_keyboard="false"
+deviceinfo_external_storage="true"
+deviceinfo_screen_width="600"
+deviceinfo_screen_height="1024"
+deviceinfo_chassis="tablet"
+
+# Bootloader related
+deviceinfo_flash_method="fastboot"
+deviceinfo_kernel_cmdline="bootopt=64S3,32N2,64N2 androidboot.selinux=permissive buildvariant=userdebug"
+deviceinfo_generate_bootimg="true"
+deviceinfo_bootimg_qcdt="false"
+deviceinfo_bootimg_dtb_second="false"
+deviceinfo_flash_offset_base="0x40078000"
+deviceinfo_flash_offset_kernel="0x00008000"
+deviceinfo_flash_offset_ramdisk="0x03408000"
+deviceinfo_flash_offset_second="0x00e88000"
+deviceinfo_flash_offset_tags="0x07f88000"
+deviceinfo_flash_pagesize="2048"

device/testing/linux-amazon-mustang/APKBUILD

+# Reference: <https://postmarketos.org/vendorkernel>
+# Kernel config based on: arch/arm/configs/mustang_defconfig
+
+pkgname=linux-amazon-mustang
+pkgver=4.9.77
+pkgrel=0
+pkgdesc="Amazon Fire 7 (2019) kernel fork"
+arch="armv7"
+_carch="arm"
+_flavor="amazon-mustang"
+url="https://kernel.org"
+license="GPL-2.0-only"
+options="!strip !check !tracedeps pmb:cross-native"
+makedepends="bash bc bison devicepkg-dev flex openssl-dev perl gcc6"
+
+# Compiler: GCC 6 (doesn't boot when compiled with newer versions)
+if [ "${CC:0:5}" != "gcc6-" ]; then
+	CC="gcc6-$CC"
+	HOSTCC="gcc6-gcc"
+	CROSS_COMPILE="gcc6-$CROSS_COMPILE"
+fi
+
+# Source
+_repository="android_kernel_amazon_mustang"
+_commit="42d97d6450e8ba87315543081a765b0f0a1da358"
+_config="config-$_flavor.$arch"
+source="
+	$pkgname-$_commit.tar.gz::https://github.com/ggow/$_repository/archive/$_commit.tar.gz
+	$_config
+	pinctrl-mtk-common.patch
+"
+builddir="$srcdir/$_repository-$_commit"
+_outdir="out"
+
+prepare() {
+	default_prepare
+	. downstreamkernel_prepare
+}
+
+build() {
+	unset LDFLAGS
+	make O="$_outdir" ARCH="$_carch" CC="${CC:-gcc}" \
+		KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-postmarketOS"
+}
+
+package() {
+	downstreamkernel_package "$builddir" "$pkgdir" "$_carch" "$_flavor" "$_outdir"
+}
+
+sha512sums="af94e53334bf7ad4541d8813eb8ef6902a352d9ee0951193a3031189d2c232b1cc1fe00a263958b617cea2af7761a56c4144db702d47cde0aed4e8c268d23f0c  linux-amazon-mustang-42d97d6450e8ba87315543081a765b0f0a1da358.tar.gz
+8b2a3bd95fffef958488117e42b436b022c7edb07017c0dd3ad02b302947303660ff6b9d852c4efb59e528b867e1a7fa998b218f0ef20efe8ce970495fa3f3d1  config-amazon-mustang.armv7
+f1ce4270766e992bc2c03821cf2e62c60d987adb7f448d5ae7430f6eba4d0d6718f337c9f0d7e4db4097f5f49d5b49e653fcb6a1ee50fa8d07b625bb04a87484  pinctrl-mtk-common.patch"

device/testing/linux-amazon-mustang/pinctrl-mtk-common.patch

+commit d5a43cdd4e2ce4ee432011501da0fdfa0096ef7e
+Author: Shana <devfusediboot@protonmail.com>
+Date:   Sat May 23 19:07:12 2020 -0700
+
+    drivers: pinctrl: mediatek: fix compile error on GCC 6
+
+diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common.h b/drivers/pinctrl/mediatek/pinctrl-mtk-common.h
+index 7250f25e..83e98b34 100644
+--- a/drivers/pinctrl/mediatek/pinctrl-mtk-common.h
++++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common.h
+@@ -356,7 +356,7 @@ struct mtk_pinctrl_devdata {
+ 	const struct mtk_pin_info		*pin_drve8_grps;
+ 	unsigned int			n_pin_drve8;
+ #endif
+-	const const struct mtk_pin_drv_grp	*pin_drv_grp;
++	const struct mtk_pin_drv_grp	*pin_drv_grp;
+ 	unsigned int			n_pin_drv_grps;
+ 	int (*spec_pull_set)(struct regmap *reg, unsigned int pin,
+ 		unsigned char align, bool isup, unsigned int arg);