Tutorial GPIO keys Mainline Linux

[ua3nbw]

overlay examples: GPIO keys Mainline Linux OrangePi

gpio-keys.dts

/dts-v1/;
/plugin/;

/ {
	compatible = "allwinner,sun4i-a10", "allwinner,sun7i-a20", "allwinner,sun8i-h3", "allwinner,sun50i-a64", "allwinner,sun50i-h5";

	fragment@0 {
		target = <&pio>;
		__overlay__ {
			 gpio_keys: gpio_keys {
				pins = "PA7","PA8","PA9","PA10","PA21";
				function = "gpio_in";
				bias-pull-up;
			};
		};
	};

	fragment@1 {
		target-path = "/";
		__overlay__ {
			gpio-keys-user {

				compatible = "gpio-keys";
				pinctrl-names = "default";
				pinctrl-0 = <&gpio_keys>;

				g-keys_up {
					label = "GPIO KEY_UP";
					linux,code = <103>; /* KEY_UP, see /usr/include/linux/input-event-codes.h */
					gpios = <&pio 0 7 1>; /* PA7 GPIO_ACTIVE_LOW */
				};

				g-keys_down {
					label = "GPIO KEY_DOWN";
					linux,code = <108>; /* KEY_DOWN, see /usr/include/linux/input-event-codes.h */
					gpios = <&pio 0 8 1>; /* PA8 GPIO_ACTIVE_LOW */
				};

				g-keys_left {
					label = "GPIO KEY_LEFT";
					linux,code = <105>; /* KEY_LEFT, see /usr/include/linux/input-event-codes.h */
					gpios = <&pio 0 9 1>; /* PA9 GPIO_ACTIVE_LOW */
				};

				g-keys_right {
					label = "GPIO KEY_RIGHT";
					linux,code = <106>; /* KEY_RIGHT, see /usr/include/linux/input-event-codes.h */
					gpios = <&pio 0 10 1>; /* PA10 GPIO_ACTIVE_LOW */
				};
				g-keys_enter {
					label = "GPIO KEY_ENTER";
					linux,code = <28>; /* KEY_ENTER, see /usr/include/linux/input-event-codes.h */
					gpios = <&pio 0 21 1>; /* PA21 GPIO_ACTIVE_LOW */
				};

			};
		};
	};
};

https://github.com/ua3nbw-cf/gpio-keys