Re: [PATCH v5 1/3] dt-bindings: pwm: Add Raspberry Pi RP1 PWM controller

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The binding advertises optional DMA support but omits the required `dmas` and `dma-names` properties, causing schema validation to fail for fully-described hardware.
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commit e8a66b347923785d0769453c48739036bf8237d0
Author: Naushir Patuck <naush@raspberrypi.com>

dt-bindings: pwm: Add Raspberry Pi RP1 PWM controller

This commit adds the devicetree binding documentation for the PWM controller
found in the Raspberry Pi RP1 chipset.

> diff --git a/Documentation/devicetree/bindings/pwm/raspberrypi,rp1-pwm.yaml b/Documentation/devicetree/bindings/pwm/raspberrypi,rp1-pwm.yaml
> new file mode 100644
> index 0000000000000..6f8461d0454f7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pwm/raspberrypi,rp1-pwm.yaml

[ ... ]

> +description: |
> +  The PWM peripheral is a flexible waveform generator with a
> +  variety of operational modes. It has the following features:
> +   - four independent output channels
> +   - 32-bit counter widths
> +   - Seven output generation modes
> +   - Optional per-channel output inversion
> +   - Optional duty-cycle data FIFO with DMA support
> +   - Optional sigma-delta noise shaping engine
> +  Serves as a fan speed provider to other nodes for a PWM-connected
> +  fan using shared registers (syscon).
> +
> +properties:
> +  compatible:
> +    const: raspberrypi,rp1-pwm
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  "#pwm-cells":
> +    const: 3
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +
> +unevaluatedProperties: false

[Severity: Low]
Since the description advertises optional DMA support, should the properties
block also define dmas and dma-names?

With unevaluatedProperties set to false, any device tree node that tries to
describe the hardware's DMA channels will fail schema validation. Even if the
OS driver does not yet implement DMA support, shouldn't the binding fully
describe the hardware capabilities so fully-described nodes aren't rejected?

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Sashiko AI review · https://sashiko.dev/#/patchset/cover.1780670224.git.andrea.porta@suse.com?part=1