Added PCF8574A overlay for RaspberryPi 4B, added libconfig.

external_tree/board/iminc/raspberrypi-4b-system-agent/overlays/pcf8574a.dts

@@ -0,0 +1,48 @@
+// Device tree overlay for I2C connected Goodix gt9271 multiple touch controller
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2835";
+
+	fragment@0 {
+		target = <&gpio>;
+		__overlay__ {
+			pcf8574a_pins: pcf8574a_pins {
+				brcm,pins = <4>; // interrupt and reset
+				brcm,function = <0>; // in
+				brcm,pull = <2>; // pull-up
+			};
+		};
+	};
+
+	fragment@1 {
+		target = <&i2c1>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "okay";
+
+			pcf8574a: pcf8574a@3f {
+				compatible = "nxp,pcf8574a";
+				reg = <0x3f>;
+				#gpio-cells = <2>;
+				gpio-controller;
+				pinctrl-names = "default";
+				pinctrl-0 = <&pcf8574a_pins>;
+				interrupt-parent = <&gpio>;
+				interrupt-controller;
+				#interrupt-cells = <2>;
+				interrupts = <4>; // high-to-low edge triggered
+				irq-gpios = <&gpio 4>; // Pin7 on GPIO header
+			};
+		};
+	};
+
+	__overrides__ {
+		addr = <&pcf8574a>,"reg:0";
+		interrupt = <&pcf8574a_pins>,"brcm,pins:0",
+			<&pcf8574a>,"interrupts:0",
+			<&pcf8574a>,"irq-gpios:4";
+	};
+};

external_tree/board/iminc/raspberrypi-4b-system-agent/post-image.sh

@@ -28,6 +28,16 @@ __EOF__
 
 # enable 64bits support
 arm_64bit=1
+__EOF__
+		fi
+		;;
+		--add-pcf8574a-overlay)
+		if ! grep -qE '^dtoverlay=pcf8574a' "${BINARIES_DIR}/rpi-firmware/config.txt"; then
+			echo "Adding 'dtoverlay=pcf8574a' to config.txt."
+			cat << __EOF__ >> "${BINARIES_DIR}/rpi-firmware/config.txt"
+
+# Add PCF8574A GPIO expander
+dtoverlay=pcf8574a,addr=0x3f,interrupt=0x22
 __EOF__
 		fi
 		;;
@@ -50,6 +60,8 @@ ROOTPATH_TMP="$(mktemp -d)"
 
 rm -rf "${GENIMAGE_TMP}"
 
+mv "${BINARIES_DIR}/pcf8574a.dtb" "${BINARIES_DIR}/rpi-firmware/overlays/pcf8574a.dtbo"
+
 genimage \
 	--rootpath "${ROOTPATH_TMP}"   \
 	--tmppath "${GENIMAGE_TMP}"    \

external_tree/configs/system_agent_orangepi_pc_defconfig

@@ -50,6 +50,7 @@ BR2_PACKAGE_UBOOT_TOOLS_MKENVIMAGE=y
 BR2_PACKAGE_UBOOT_TOOLS_DUMPIMAGE=y
 BR2_PACKAGE_LIBOPENSSL_BIN=y
 BR2_PACKAGE_LIBOPENSSL_ENGINES=y
+BR2_PACKAGE_LIBCONFIG=y
 BR2_PACKAGE_LIBGPIOD=y
 BR2_PACKAGE_LIBGPIOD_TOOLS=y
 BR2_PACKAGE_LIBIIO=y

external_tree/configs/system_agent_pine64_plus_defconfig

@@ -50,6 +50,7 @@ BR2_PACKAGE_UBOOT_TOOLS_MKENVIMAGE=y
 BR2_PACKAGE_UBOOT_TOOLS_DUMPIMAGE=y
 BR2_PACKAGE_LIBOPENSSL_BIN=y
 BR2_PACKAGE_LIBOPENSSL_ENGINES=y
+BR2_PACKAGE_LIBCONFIG=y
 BR2_PACKAGE_LIBGPIOD=y
 BR2_PACKAGE_LIBGPIOD_TOOLS=y
 BR2_PACKAGE_LIBIIO=y

external_tree/configs/system_agent_raspberrypi_4b_defconfig

@@ -23,7 +23,7 @@ BR2_ROOTFS_USERS_TABLES="$(BR2_EXTERNAL_system_agent_PATH)/customizations/users.
 BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_system_agent_PATH)/customizations/overlay"
 BR2_ROOTFS_POST_BUILD_SCRIPT="$(BR2_EXTERNAL_system_agent_PATH)/board/iminc/raspberrypi-4b-system-agent/post-build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="$(BR2_EXTERNAL_system_agent_PATH)/board/iminc/raspberrypi-4b-system-agent/post-image.sh"
-BR2_ROOTFS_POST_SCRIPT_ARGS="--add-miniuart-bt-overlay --aarch64"
+BR2_ROOTFS_POST_SCRIPT_ARGS="--add-miniuart-bt-overlay --aarch64 --add-pcf8574a-overlay"
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_TARBALL=y
 BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION="$(call github,raspberrypi,linux,081f560bde7188ca6f40cf297bd55c680e0179c0)/linux-081f560bde7188ca6f40cf297bd55c680e0179c0.tar.gz"
@@ -31,6 +31,7 @@ BR2_LINUX_KERNEL_DEFCONFIG="bcm2711"
 BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="$(BR2_EXTERNAL_system_agent_PATH)/board/iminc/raspberrypi-4b-system-agent/linux.fragment"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
 BR2_LINUX_KERNEL_INTREE_DTS_NAME="broadcom/bcm2711-rpi-4-b"
+BR2_LINUX_KERNEL_CUSTOM_DTS_PATH="$(BR2_EXTERNAL_system_agent_PATH)/board/iminc/raspberrypi-4b-system-agent/overlays/pcf8574a.dts"
 BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
 BR2_PACKAGE_LINUX_TOOLS_CPUPOWER=y
 BR2_PACKAGE_LINUX_TOOLS_GPIO=y
@@ -52,6 +53,7 @@ BR2_PACKAGE_UBOOT_TOOLS_MKENVIMAGE=y
 BR2_PACKAGE_UBOOT_TOOLS_DUMPIMAGE=y
 BR2_PACKAGE_LIBOPENSSL_BIN=y
 BR2_PACKAGE_LIBOPENSSL_ENGINES=y
+BR2_PACKAGE_LIBCONFIG=y
 BR2_PACKAGE_LIBGPIOD=y
 BR2_PACKAGE_LIBGPIOD_TOOLS=y
 BR2_PACKAGE_LIBIIO=y
@@ -72,7 +74,7 @@ BR2_PACKAGE_UTIL_LINUX_HWCLOCK=y
 BR2_PACKAGE_VIM=y
 BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_ROOTFS_EXT2_4=y
-BR2_TARGET_ROOTFS_EXT2_SIZE="128M"
+BR2_TARGET_ROOTFS_EXT2_SIZE="256M"
 # BR2_TARGET_ROOTFS_TAR is not set
 BR2_PACKAGE_HOST_DOSFSTOOLS=y
 BR2_PACKAGE_HOST_GENIMAGE=y