[PATCH 1/3 v3] dt-bindings: backlight: Add some common backlight properties

[Daniel Thompson]

On Wed, Aug 19, 2020 at 10:51:48PM +0200, Linus Walleij wrote:
> Let's use a common.yaml include for the backlight like we do with
> the LEDs. The LEDs are inherently incompatible so their bindings
> cannot be reused for backlight.
> 
> Cc: devicetree at vger.kernel.org
> Suggested-by: Sam Ravnborg <sam at ravnborg.org>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>

Reviewed-by: Daniel Thompson <daniel.thompson at linaro.org>


> ---
> ChangeLog v2->v3:
> - Drop the | for the description
> - Drop the "default-on" property, we're not using it.
> - Drop the minimum 0 for unsigned u32:s
> ChangeLog v1->v2:
> - New patch as suggested by Sam.
> ---
>  .../bindings/leds/backlight/common.yaml       | 34 +++++++++++++++++++
>  1 file changed, 34 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/backlight/common.yaml
> 
> diff --git a/Documentation/devicetree/bindings/leds/backlight/common.yaml b/Documentation/devicetree/bindings/leds/backlight/common.yaml
> new file mode 100644
> index 000000000000..4e7e95e331a5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/common.yaml
> @@ -0,0 +1,34 @@
> +# 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.jones at linaro.org>
> +  - Daniel Thompson <daniel.thompson at linaro.org>
> +  - Jingoo Han <jingoohan1 at 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
> -- 
> 2.26.2
>