Documentation/devicetree/bindings/input/gpio-keys.yaml

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

title: Device-Tree bindings for GPIO attached keys

maintainers:
  - Rob Herring <robh@kernel.org>

properties:
  compatible:
    enum:
      - gpio-keys
      - gpio-keys-polled

patternProperties:
  ".*":
    if:
      type: object
    then:
      $ref: input.yaml#

      properties:
        gpios:
          maxItems: 1

        interrupts:
          maxItems: 1

        label:
          description: Descriptive name of the key.

        linux,code:
          description: Key / Axis code to emit.
          $ref: /schemas/types.yaml#/definitions/uint32

        linux,input-type:
          description:
            Specify event type this button/key generates. If not specified defaults to
            <1> == EV_KEY.
          $ref: /schemas/types.yaml#/definitions/uint32

          default: 1

        linux,input-value:
          description: |
            If linux,input-type is EV_ABS or EV_REL then this
            value is sent for events this button generates when pressed.
            EV_ABS/EV_REL axis will generate an event with a value of 0
            when all buttons with linux,input-type == type and
            linux,code == axis are released. This value is interpreted
            as a signed 32 bit value, e.g. to make a button generate a
            value of -1 use:

            linux,input-value = <0xffffffff>; /* -1 */

          $ref: /schemas/types.yaml#/definitions/uint32

        debounce-interval:
          description:
            Debouncing interval time in milliseconds. If not specified defaults to 5.
          $ref: /schemas/types.yaml#/definitions/uint32

          default: 5

        wakeup-source:
          description: Button can wake-up the system.

        wakeup-event-action:
          description: |
            Specifies whether the key should wake the system when asserted, when
            deasserted, or both. This property is only valid for keys that wake up the
            system (e.g., when the "wakeup-source" property is also provided).

            Supported values are defined in linux-event-codes.h:

              EV_ACT_ANY        - both asserted and deasserted
              EV_ACT_ASSERTED   - asserted
              EV_ACT_DEASSERTED - deasserted
          $ref: /schemas/types.yaml#/definitions/uint32
          enum: [0, 1, 2]

        linux,can-disable:
          description:
            Indicates that button is connected to dedicated (not shared) interrupt
            which can be disabled to suppress events from the button.
          type: boolean

      required:
        - linux,code

      anyOf:
        - required:
            - interrupts
        - required:
            - gpios

      dependencies:
        wakeup-event-action: [ wakeup-source ]
        linux,input-value: [ gpios ]

      unevaluatedProperties: false

if:
  properties:
    compatible:
      const: gpio-keys-polled
then:
  properties:
    poll-interval:
      description:
        Poll interval time in milliseconds
      $ref: /schemas/types.yaml#/definitions/uint32

  required:
    - poll-interval

additionalProperties: false

examples:
  - |
    #include <dt-bindings/interrupt-controller/irq.h>

    gpio-keys {
        compatible = "gpio-keys";
        autorepeat;

        up {
            label = "GPIO Key UP";
            linux,code = <103>;
            gpios = <&gpio1 0 1>;
        };

        down {
            label = "GPIO Key DOWN";
            linux,code = <108>;
            interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
        };
    };

...