[PATCH 1/3 v2] dt-bindings: backlight: Add some common backlight properties
Rob Herring
robh at kernel.org
Wed Aug 12 15:46:16 UTC 2020
On Wed, Aug 12, 2020 at 2:58 AM Linus Walleij <linus.walleij at linaro.org> 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>
> ---
> ChangeLog v1->v2:
> - New patch as suggested by Sam.
> ---
> .../bindings/leds/backlight/common.yaml | 42 +++++++++++++++++++
> 1 file changed, 42 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/backlight/common.yaml
I'd expect some refactoring here with existing backlight schemas
including the ones I just added for 5.9.
Ideally, we shouldn't have any property have a type definition more
than once. (We don't have any way to detect that though it wouldn't be
hard to write a program to do so).
> diff --git a/Documentation/devicetree/bindings/leds/backlight/common.yaml b/Documentation/devicetree/bindings/leds/backlight/common.yaml
> new file mode 100644
> index 000000000000..8ae7e3818b0d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/common.yaml
> @@ -0,0 +1,42 @@
> +# 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: |
You don't need '|' if there's no formatting to preserve.
> + Backlight devices provide backlight for different types of graphical
> + displays. They are typically but not necessarilt implemented using a white
typo
> + LED powered by a boost converter.
> +
> +properties:
> + default-on:
> + description:
> + The initial state of the backlight can be set to be on with this
> + property. This is a state applied by the operating system so that the
> + backlight is always turned on at boot.
Needs a type.
> +
> + 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
> + minimum: 0
It's an unsigned int, so the min is already 0.
> +
> + 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
> + minimum: 0
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