Re: [RFC PATCH 7/7] dt-bindings: motion: Add motion-simple-pwm bindings

David Jander
2025-02-28T09:22:05Z

Dear Krzysztof,

Thanks for reviewing...

On Fri, 28 Feb 2025 08:12:45 +0100
Krzysztof Kozlowski <krzk@kernel.org> wrote:

> On Thu, Feb 27, 2025 at 05:28:23PM +0100, David Jander wrote:
> [...]
> > +description: |
>
> Do not need '|' unless you need to preserve formatting.
>
> > + Simple motor control device based on 1 or 2 PWM outputs
>
> Your schema does not allow 1. Test it.

Ok, that came as a surprise to me. Thanks!

> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - motion-simple-pwm
> > +
> > + pwms:
> > + maxItems: 2
>
> List and describe items instead.
>
> > +
> > + pwm-names:
> > + maxItems: 2
>
> List items instead.

Will do in next iteration. Thanks.

> > +
> > + motion,pwm-inverted:
> > + $ref: /schemas/types.yaml#/definitions/flag
>
> And PWM flag does not work?

I have seen PWM controllers that don't seem to support the
PWM_POLARITY_INVERTED flag and those where it just doesn't work. Should all
PWM controller drivers always support the PWM_POLARITY_INVERTED flag, even if
it needs to be inverted in software? If so, there are some drivers that need
fixing.

> Anyway, there is no "motion" company.

Got it. Dropped all the "motion," prefixes.

> > + description:
> > + If present, this flag indicates that the PWM signal should be inverted.
> > + The duty-cycle will be scaled from 100% down to 0% instead 0% to 100%.
> > +
> > +required:
> > + - compatible
> > + - pwms
> > +
> > +allOf:
> > + - $ref: /schemas/motion/common.yaml#
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > + - |
> > + // This example shows how to use the TI DRV8873 or similar motor controllers
> > + // with this driver
> > + motion-simple-pwm0 {
>
> Node names should be generic. See also an explanation and list of
> examples (not exhaustive) in DT specification:
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
>
> e.g. motor {

Will change. Thanks.

Best regards,

--
David Jander