gpio-rotary.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__ {
			pinctrl_button: pinctrl_button {
				pins = "PA6";
				function = "gpio_in";
				bias-pull-up;
			};
			pinctrl_rotary: pinctrl_rotary {
				pins = "PG8","PG9";
				function = "gpio_in";
				bias-pull-up;
			};
		};
	};

	fragment@1 {
		target-path = "/";
		__overlay__ {
			rotary_button {
				compatible = "gpio-keys";
				pinctrl-names = "default";
				pinctrl-0 = <&pinctrl_button>;

				rotary_button_enter {
					label = "ENTER";
					linux,code = <99>; /* KEY_SYSRQ - see linux/input.h */
					gpios = <&pio 0 6 1>; /* PA6 GPIO_ACTIVE_LOW */
				};
			};
			rotary_axis {
				/* https://mchehab.fedorapeople.org/kernel_docs/input/devices/rotary-encoder.html */
				compatible = "rotary-encoder";
				pinctrl-names = "default";
				pinctrl-0 = <&pinctrl_rotary>;
				gpios = <&pio 6 9 1>, <&pio 6 8 1>; /* PG8 PG9 GPIO_ACTIVE_LOW */
				linux,axis = <1>; /* REL_Y */
				rotary-encoder,relative-axis;
				rotary-encoder,half-period;
			};
		};
	};
};