/*
 * Devicetree overlay for GPIO based backlight on/off capability.
 *
 * Use this if you have one of those HDMI displays whose backlight cannot be
 * controlled via DPMS over HDMI and plan to do a little soldering to use an
 * RPi gpio pin for on/off switching.
 *
 * See: https://www.waveshare.com/wiki/7inch_HDMI_LCD_(C)#Backlight_Control
 *
 */
/dts-v1/;
/plugin/;

/ {
	compatible = "brcm,bcm2835";

	fragment@1 {
		target = <&gpio>;
		__overlay__ {
			hdmi_backlight_hwhack_gpio_pins: hdmi_backlight_hwhack_gpio_pins {
				brcm,pins = <17>;
				brcm,function = <1>; /* out */
			};
		};
	};

	fragment@2 {
		target-path = "/";
		__overlay__ {
			hdmi_backlight_hwhack_gpio: hdmi_backlight_hwhack_gpio {
				compatible = "gpio-backlight";

				pinctrl-names = "default";
				pinctrl-0 = <&hdmi_backlight_hwhack_gpio_pins>;

				gpios = <&gpio 17 0>;
				default-on;
			};
		};
	};

	__overrides__ {
		gpio_pin   = <&hdmi_backlight_hwhack_gpio>,"gpios:4",
		             <&hdmi_backlight_hwhack_gpio_pins>,"brcm,pins:0";
		active_low = <&hdmi_backlight_hwhack_gpio>,"gpios:8";
	};
};