Re: [PATCH v3 2/3] dt-bindings: leds: add dt schema for worldsemi,ws2812b

[Chuanhong Guo]

Hi!

On Thu, Dec 8, 2022 at 3:52 PM Krzysztof Kozlowski
<krzysztof.kozlowski@xxxxxxxxxx> wrote:
>
> On 07/12/2022 05:09, Chuanhong Guo wrote:
> > Add dt binding schema for WorldSemi WS2812B driven using SPI
> > bus.
> >
> > Signed-off-by: Chuanhong Guo <gch981213@xxxxxxxxx>
> > ---
> > Changes since v1:
> > remove linux driver reference from description
> > remove some obvious descriptions
> > fix unit address regex in multi-led property
> > drop various minItems
> > add maxItems = 1 to reg
> > fix node names and property orders in binding example
> > drop -spi from compatible string
> > add default-brightness
> >
> > Change since v2:
> > drop "this patch" from commit message
> > rename leds to led-controller
> > drop default-brightness and default-intensity
> >
> >  .../bindings/leds/worldsemi,ws2812b.yaml      | 116 ++++++++++++++++++
> >  1 file changed, 116 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/leds/worldsemi,ws2812b.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/leds/worldsemi,ws2812b.yaml b/Documentation/devicetree/bindings/leds/worldsemi,ws2812b.yaml
> > new file mode 100644
> > index 000000000000..548c05ac3d31
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/leds/worldsemi,ws2812b.yaml
> > @@ -0,0 +1,116 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/leds/worldsemi,ws2812b.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: WS2812B LEDs driven using SPI
> > +
> > +maintainers:
> > +  - Chuanhong Guo <gch981213@xxxxxxxxx>
> > +
> > +description: |
> > +  WorldSemi WS2812B is a individually addressable LED chip that can be chained
> > +  together and controlled individually using a single wire.
> > +  This binding describes a chain of WS2812B LEDs connected to the SPI MOSI pin.
> > +  Typical setups includes connecting the data pin of the LED chain to MOSI as
> > +  the only device or using CS and MOSI with a tri-state voltage-level shifter
> > +  for the data pin.
> > +  The SPI frequency needs to be 2.105MHz~2.85MHz for the timing to be correct
> > +  and the controller needs to send all the bytes continuously.
> > +
> > +allOf:
> > +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    const: worldsemi,ws2812b
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  spi-max-frequency:
> > +    minimum: 2105000
> > +    maximum: 2850000
> > +
> > +  "#address-cells":
> > +    const: 1
> > +
> > +  "#size-cells":
> > +    const: 0
> > +
> > +patternProperties:
> > +  "^multi-led@[0-9a-f]+$":
> > +    type: object
> > +    $ref: leds-class-multicolor.yaml#
> > +    unevaluatedProperties: false
> > +
> > +    properties:
> > +      color-index:
> > +        description: |
> > +          A 3-item array specifying color of each components in this LED. It
> > +          should be one of the LED_COLOR_ID_* prefixed definitions from the
> > +          header include/dt-bindings/leds/common.h. Defaults to
> > +          <LED_COLOR_ID_GREEN LED_COLOR_ID_RED LED_COLOR_ID_BLUE>
> > +          if unspecified.
> > +        $ref: /schemas/types.yaml#/definitions/uint32-array
>
> Hmm, maybe we should add more colors the "color" property, like
> LED_COLOR_ID_GRB, LED_COLOR_ID_BRG, LED_COLOR_ID_BGR?

Considering the existence of RGBW LEDs, this approach means adding
30 more COLOR_IDs. I think that's too many entries and is inconvenient
to parse in code.

> Rest look ok for me. If there is going to be resend, drop redundant "dt
> schema for" from the subject.

OK.

-- 
Regards,
Chuanhong Guo