Re: [PATCH v3 3/4] dt-bindings: leds: Add binding for a multicolor group of LEDs

From: Sascha Hauer
Date: Wed Aug 24 2022 - 08:22:17 EST


On Wed, Aug 24, 2022 at 12:30:31PM +0200, Jean-Jacques Hiblot wrote:
> This allows to group multiple monochromatic LEDs into a multicolor
> LED, e.g. RGB LEDs.
>
> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> .../bindings/leds/leds-group-multicolor.yaml | 61 +++++++++++++++++++
> 1 file changed, 61 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/leds-group-multicolor.yaml
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-group-multicolor.yaml b/Documentation/devicetree/bindings/leds/leds-group-multicolor.yaml
> new file mode 100644
> index 000000000000..79e5882a08e2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-group-multicolor.yaml
> @@ -0,0 +1,61 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/leds-group-multicolor.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Multi-color LED built with monochromatic LEDs
> +
> +maintainers:
> + - Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
> +
> +description: |
> + This driver combines several monochromatic LEDs into one multi-color
> + LED using the multicolor LED class.
> +
> +properties:
> + compatible:
> + const: leds-group-multicolor
> +
> + leds:
> + description:
> + An aray of monochromatic leds
> + $ref: /schemas/types.yaml#/definitions/phandle-array
> +
> +required:
> + - leds
> +
> +allOf:
> + - $ref: leds-class-multicolor.yaml#
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> + #include <dt-bindings/leds/common.h>
> +
> + monochromatic-leds {
> + compatible = "gpio-leds";
> +
> + led0: led-0 {
> + gpios = <&mcu_pio 0 GPIO_ACTIVE_LOW>;
> + };
> +
> + led1: led-1 {
> + gpios = <&mcu_pio 1 GPIO_ACTIVE_HIGH>;
> + };
> +
> + led2: led-2 {
> + gpios = <&mcu_pio 1 GPIO_ACTIVE_HIGH>;
> + };

led-2 has the same GPIO as led-1, should likely be <&mcu_pio 2 GPIO_ACTIVE_HIGH>;

> + };
> +
> + multi-led {
> + compatible = "leds-group-multicolor";
> + color = <LED_COLOR_ID_RGB>;
> + function = LED_FUNCTION_INDICATOR;
> + leds = <&led0>, <&led1>, <&led2>;
> + };

When reading this I wondered how the driver knows which LED has which
color. Should you assign colors to the individual LEDs to make that
clear in the example?

Sascha

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