Documentation/devicetree/bindings/leds/backlight/common.yaml

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/backlight/common.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Common backlight properties

maintainers:
  - Lee Jones <lee@kernel.org>
  - Daniel Thompson <daniel.thompson@linaro.org>
  - Jingoo Han <jingoohan1@gmail.com>

description:
  Backlight devices provide backlight for different types of graphical
  displays. They are typically but not necessarily implemented using a white
  LED powered by a boost converter.

properties:
  default-brightness:
    description:
      The default brightness that should be applied to the LED by the operating
      system on start-up. The brightness should not exceed the brightness the
      LED can provide.
    $ref: /schemas/types.yaml#/definitions/uint32

  max-brightness:
    description:
      Normally the maximum brightness is determined by the hardware and this
      property is not required. This property is used to put a software limit
      on the brightness apart from what the driver says, as it could happen
      that a LED can be made so bright that it gets damaged or causes damage
      due to restrictions in a specific system, such as mounting conditions.
    $ref: /schemas/types.yaml#/definitions/uint32

  brightness-levels:
    description:
      Array of distinct brightness levels. The levels must be in the range
      accepted by the underlying LED device. Typically these are in the range
      from 0 to 255, but any range starting at 0 will do, as long as they are
      accepted by the LED.
      The 0 value means a 0% of brightness (darkest/off), while the last value
      in the array represents a full 100% brightness (brightest).
      If this array is not provided, the driver default mapping is used.
    $ref: /schemas/types.yaml#/definitions/uint32-array

  default-brightness-level:
    description:
      The default brightness level (index into the array defined by the
      "brightness-levels" property).
    $ref: /schemas/types.yaml#/definitions/uint32

additionalProperties: true