Re: [PATCH] dt-bindings: pwm: st: convert sti-pwm to DT schema

[Raphaël Gallais-Pou]

Hi,

Le 03/08/2023 à 18:09, Conor Dooley a écrit :
> On Thu, Aug 03, 2023 at 10:56:45AM +0200, Uwe Kleine-König wrote:
> > On Thu, Aug 03, 2023 at 09:18:14AM +0200, Raphaël Gallais-Pou wrote:
> > > Hi
> > >
> > > Le 02/08/2023 à 10:02, Uwe Kleine-König a écrit :
> > > > Hello,
> > > >
> > > > On Wed, Aug 02, 2023 at 12:05:59AM +0200, Raphael Gallais-Pou wrote:
> > > > > +  st,capture-num-chan:
> > > > > +    $ref: "/schemas/types.yaml#/definitions/uint32"
> > > > > +    description: Number of available Capture channels.
> > > >
> > > > I have the theory that nobody actually uses the capture feature and I'd
> > > > like to get rid of it. People who do use it, should better switch to the
> > > > counter driver.
> > >
> > > TBH I only found two drivers using it, including this one.
> > >
> > > $ grep -rinI "\.capture" drivers/pwm/ | wc -l
> > > 2
> >
> > Right, there is pwm-stm32 and pwm-sti that support capture.
> >
> > There are a few machines that have a st,sti-pwm device:
> >
> > 	$ grep -rl st,sti-pwm arch/arm/boot/dts/*.dtb
> > 	arch/arm/boot/dts/stih407-b2120.dtb
> > 	arch/arm/boot/dts/stih410-b2120.dtb
> > 	arch/arm/boot/dts/stih410-b2260.dtb
> > 	arch/arm/boot/dts/stih418-b2199.dtb
> > 	arch/arm/boot/dts/stih418-b2264.dtb
> >
> > but to actually use capture the device tree must have a property
> > st,capture-num-chan. "st,capture-num-chan" isn't set by any of the
> > devices.

This is also what I came across, this is the reason why I'm not 
reluctant to remove it.

> > I think for stm32 it's not that trivial to show that it's unused.
> > While the capture code isn't a big maintenance burden, I still would
> > prefer to get rid of it if nobody uses it. Still more given that there
> > are better alternatives available.

Regarding stm32, I think the owner of the driver would prefer to handle it.

> > > If there is no opposition about removing this feature I suggest to do it in
> > > a second time, in a serie.
> >
> > Does that mean you will do that? I guess not, but at least this means
> > you're not using capture support.
>
> It seems like it should either be done as part of the conversion or as a
> second patch in the series doing the conversion /shrug

Splitting the conversion and the capture removal is clearer IMO. Mixing 
both could lead to confusion. I'll send another serie to do this.


Regards,
Raphaël