boards: aesc: ElemRV-N: Add GPIO Controller

ElemRV-N has a gpio controller. Enable this node in the board-level
device-tree and add this interface to all aux. files.

Also sort device-tree nodes in the DTS file alphabetically.

Signed-off-by: Daniel Schultz <dnltz@aesc-silicon.de>

boards/aesc/elemrv/doc/index.rst

@@ -62,6 +62,22 @@ To evaluate the UART interface, build and run the following sample:
    :zephyr-app: samples/hello_world
    :goals: build
 
+GPIO
+====
+
+The GPIO (General-Purpose Input/Output) interface with tri-state pins is a digital interface that
+allows each pin to be configured as either an input or an output, with additional control for
+setting the direction of data flow.
+
+``gpio`` consists of a total of 12 individual pins.
+
+The Blinky sample provides a simple way to explore how a GPIO can be used to control an external LED.
+
+.. zephyr-app-commands::
+   :board: elemrv/elemrv_n
+   :zephyr-app: samples/basic/blinky
+   :goals: build
+
 .. _GitHub Project:
    https://github.com/aesc-silicon/elemrv
 

boards/aesc/elemrv/elemrv_elemrv_n.dts

@@ -12,6 +12,10 @@
 	model = "ElemRV-N";
 	compatible = "aesc,elemrv-n";
 
+	aliases {
+		led0 = &led0;
+	};
+
 	chosen {
 		zephyr,console = &uart0;
 		zephyr,shell-uart = &uart0;
@@ -19,6 +23,15 @@
 		zephyr,flash = &flash;
 	};
 
+	leds: leds {
+		compatible = "gpio-leds";
+
+		led0: led0 {
+			gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
+			label = "LED_0";
+		};
+	};
+
 	soc {
 		ocram: memory@80000000 {
 			device_type = "memory";
@@ -39,12 +52,16 @@
 	};
 };
 
+&cpu0 {
+	clock-frequency = <DT_FREQ_M(20)>;
+};
+
+&gpio0 {
+	status = "okay";
+};
+
 &uart0 {
 	clock-frequency = <DT_FREQ_M(20)>;
 	current-speed = <115200>;
 	status = "okay";
 };
-
-&cpu0 {
-	clock-frequency = <DT_FREQ_M(20)>;
-};

boards/aesc/elemrv/elemrv_elemrv_n.yaml

@@ -7,3 +7,7 @@ toolchain:
   - zephyr
 ram: 32
 flash: 32
+vendor: aesc
+supported:
+  - gpio
+  - uart

boards/aesc/elemrv/elemrv_elemrv_n_defconfig

@@ -7,3 +7,6 @@ CONFIG_SERIAL=y
 # Enable Console
 CONFIG_CONSOLE=y
 CONFIG_UART_CONSOLE=y
+
+# GPIO Driver
+CONFIG_GPIO=y