ARM: dts: rskrza1: Add input switches

Add support for input switches SW1-3 on the Renesas RZ/A1 RSK+RZA1
development board.

Note that this uses the IRQ interrupts, as the RZ/A1 GPIO controller
does not include interrupt support.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r7s72100-rskrza1.dts

@@ -8,6 +8,7 @@
 /dts-v1/;
 #include "r7s72100.dtsi"
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
 #include <dt-bindings/pinctrl/r7s72100-pinctrl.h>
 
 / {
@@ -28,6 +29,37 @@ memory@8000000 {
 		reg = <0x08000000 0x02000000>;
 	};
 
+	keyboard {
+		compatible = "gpio-keys";
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&keyboard_pins>;
+
+		key-1 {
+			interrupt-parent = <&irqc>;
+			interrupts = <3 IRQ_TYPE_EDGE_BOTH>;
+			linux,code = <KEY_1>;
+			label = "SW1";
+			wakeup-source;
+		};
+
+		key-2 {
+			interrupt-parent = <&irqc>;
+			interrupts = <2 IRQ_TYPE_EDGE_BOTH>;
+			linux,code = <KEY_2>;
+			label = "SW2";
+			wakeup-source;
+		};
+
+		key-3 {
+			interrupt-parent = <&irqc>;
+			interrupts = <5 IRQ_TYPE_EDGE_BOTH>;
+			linux,code = <KEY_3>;
+			label = "SW3";
+			wakeup-source;
+		};
+	};
+
 	lbsc {
 		#address-cells = <1>;
 		#size-cells = <1>;
@@ -101,6 +133,12 @@ i2c3_pins: i2c3 {
 			 <RZA1_PINMUX(1, 7, 1)>;	/* RIIC3SDA */
 	};
 
+	keyboard_pins: keyboard {
+		pinmux = <RZA1_PINMUX(1, 9, 3)>,	/* IRQ3 */
+			 <RZA1_PINMUX(1, 8, 3)>,	/* IRQ2 */
+			 <RZA1_PINMUX(1, 11, 3)>;	/* IRQ5 */
+	};
+
 	/* Serial Console */
 	scif2_pins: serial2 {
 		pinmux = <RZA1_PINMUX(3, 0, 6)>,	/* TxD2 */