Re: [PATCH v2 1/2] dt-binding: leds: Document leds-multi-gpio bindings

From: Rob Herring
Date: Sat Mar 27 2021 - 14:13:21 EST


On Fri, Mar 26, 2021 at 01:28:00PM +0800, Hermes Zhang wrote:
> From: Hermes Zhang <chenhuiz@xxxxxxxx>
>
> This binding represents LED devices which are controller with
> multiple GPIO lines in order to achieve more than two brightness
> states.
>
> Signed-off-by: Hermes Zhang <chenhuiz@xxxxxxxx>
> ---
> .../bindings/leds/leds-multi-gpio.yaml | 50 +++++++++++++++++++
> 1 file changed, 50 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/leds-multi-gpio.yaml
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-multi-gpio.yaml b/Documentation/devicetree/bindings/leds/leds-multi-gpio.yaml
> new file mode 100644
> index 000000000000..1549f21e8d6e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-multi-gpio.yaml
> @@ -0,0 +1,50 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/leds-multi-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Multiple GPIOs LED driver
> +
> +maintainers:
> + - Hermes Zhang <chenhuiz@xxxxxxxx>
> +
> +description:
> + This will support some LED made of multiple GPIOs and the brightness of the
> + LED could map to different states of the GPIOs.
> +
> +properties:
> + compatible:
> + const: multi-gpio-led
> +
> + led-gpios:
> + description: Array of one or more GPIOs pins used to control the LED.
> + minItems: 1
> + maxItems: 8 # Should be enough
> +
> + led-states:
> + description: |
> + The array list the supported states here which will map to brightness
> + from 0 to maximum. Each item in the array will present all the GPIOs
> + value by bit.
> + $ref: /schemas/types.yaml#/definitions/uint8-array
> + minItems: 1
> + maxItems: 256 # Should be enough

Isn't this the same as the standard 'brightness-levels' from backlight
binding? The index is the level and the value is the h/w specific
setting.

> +
> +required:
> + - compatible
> + - led-gpios
> + - led-states
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + gpios-led {
> + compatible = "multi-gpio-led";
> +
> + led-gpios = <&gpio0 23 0x1>,
> + <&gpio0 24 0x1>;
> + led-states = /bits/ 8 <0x00 0x01 0x02 0x03>;
> + };
> +...
> --
> 2.20.1
>