sun8i-h3-gpio-poweroff.dts

/dts-v1/;
/plugin/;

/* This overlay will pull a pin high to signal the OS has shutdown and
   it's safe to cut power to the board (and the rest of the enclosure).

   Pulling high on shutdown is better than pulling low because once
   power has been cut the high signal will fall back to low. This means
   an SR latch won't have behave in an undefined manner when a "power
   on" button is pressed to restore power to the enclosure, as the
   "power off" signal will clear itself.

   CONFIG_POWER_RESET_GPIO and CONFIG_POWER_RESET_GPIO_RESTART need to
   be enabled in the kernel for this to work.

   See: https://www.kernel.org/doc/Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt
*/

/ {
	compatible = "allwinner,sun8i-h3";

	/* we need to take an unused pin away from the spi1 bus */
	fragment@0 {
		target = <&spi1_pins>;

		__overlay__ {
			pins = "PA15\0PA14\0PA13";
		};
	};

	fragment@1 {
		target = <&pio>;

		__overlay__ {
			power_off_pin: power_off_pin {
				pins = "PA16";
				function = "gpio_out";
				bias-pull-down;
			};
		};
	};

	fragment@2 {
		target-path = "/";

		__overlay__ {
			gpio-poweroff {
				compatible = "gpio-poweroff";
				pinctrl-names = "default";
				pinctrl-0 = <&power_off_pin>;
				gpios = <&pio 0 16 1>;
				status = "okay";
				input;
			};
		};
	};
};