Documentation/devicetree/bindings/leds/leds-gpio.yaml

# SPDX-License-Identifier: GPL-2.0-only
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/leds-gpio.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: LEDs connected to GPIO lines

maintainers:
  - Jacek Anaszewski <jacek.anaszewski@gmail.com>
  - Pavel Machek <pavel@ucw.cz>

description:
  Each LED is represented as a sub-node of the gpio-leds device.  Each
  node's name represents the name of the corresponding LED.

properties:
  compatible:
    const: gpio-leds

patternProperties:
  # The first form is preferred, but fall back to just 'led' anywhere in the
  # node name to at least catch some child nodes.
  "(^led-[0-9a-f]$|led)":
    type: object

    $ref: common.yaml#

    properties:
      gpios:
        maxItems: 1

      retain-state-suspended:
        description:
          The suspend state can be retained.Such as charge-led gpio.
        type: boolean

      retain-state-shutdown:
        description:
          Retain the state of the LED on shutdown. Useful in BMC systems, for
          example when the BMC is rebooted while the host remains up.
        type: boolean

    required:
      - gpios

additionalProperties: false

examples:
  - |

    #include <dt-bindings/gpio/gpio.h>
    #include <dt-bindings/leds/common.h>

    leds {
        compatible = "gpio-leds";
        led-0 {
            gpios = <&mcu_pio 0 GPIO_ACTIVE_LOW>;
            linux,default-trigger = "disk-activity";
            function = LED_FUNCTION_DISK;
        };

        led-1 {
            gpios = <&mcu_pio 1 GPIO_ACTIVE_HIGH>;
            /* Keep LED on if BIOS detected hardware fault */
            default-state = "keep";
            function = LED_FUNCTION_FAULT;
        };
    };

    run-control {
        compatible = "gpio-leds";
        led-0 {
            gpios = <&mpc8572 6 GPIO_ACTIVE_HIGH>;
            color = <LED_COLOR_ID_RED>;
            default-state = "off";
        };
        led-1 {
            gpios = <&mpc8572 7 GPIO_ACTIVE_HIGH>;
            color = <LED_COLOR_ID_GREEN>;
            default-state = "on";
        };
    };

...