Re: [PATCH v2 1/7] dt-bindings: pwm: Document Tegra194 and Tegra264 controllers

From: Thierry Reding

Date: Wed Mar 25 2026 - 10:29:57 EST


On Wed, Mar 25, 2026 at 07:16:59PM +0900, Mikko Perttunen wrote:
> From: Thierry Reding <treding@xxxxxxxxxx>
>
> The PWM controller found on Tegra264 is largely compatible with the one
> on prior generations, but it comes with some extra features, hence a new
> compatible string is needed.
>
> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
> Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.yaml | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.yaml b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.yaml
> index 41cea4979132..15706d2a808d 100644
> --- a/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.yaml
> +++ b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.yaml
> @@ -16,6 +16,8 @@ properties:
> - enum:
> - nvidia,tegra20-pwm
> - nvidia,tegra186-pwm
> + - nvidia,tegra194-pwm
> + - nvidia,tegra264-pwm

I think this was lost during the earlier conversation we had on the
split of these patches. Krzysztof had pointed out that tegra194-pwm is
now a duplicate entry. I don't know exactly how it ended up like this,
but I'm pretty sure what I meant was:

- items:
- const: tegra264-pwm
- const: tegra194-pwm

This mirrors the fact that this is in fact backwards-compatible with
Tegra194 but also has additional features that we need the Tegra264
compatible string for.

Krzysztof also requested that we drop the latter part of, or reword, the
commit message because we always want the compatible string to be added,
regardless of backwards-compatibility, etc.

So I think maybe something like this would be better for the commit
message:

The PWM controller found on Tegra264 is largely compatible with the one
on prior generations, but it comes with some extra features. The new
Tegra264-specific compatible string can be used to distinguish between
the feature sets.

Thierry

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