Re: [PATCH 3/7] pwm: dwc: add of/platform support

[Ben Dooks]

On 13/07/2022 16:07, Uwe Kleine-König wrote:
> On Wed, Jul 13, 2022 at 03:30:07PM +0100, Ben Dooks wrote:
> > On 13/07/2022 14:52, Uwe Kleine-König wrote:
> > > On Wed, Jul 13, 2022 at 12:56:55PM +0100, Ben Dooks wrote:
> > > > On 12/07/2022 23:17, Rob Herring wrote:
> > > > > On Tue, Jul 12, 2022 at 11:01:09AM +0100, Ben Dooks wrote:
> > > > > > The dwc pwm controller can be used in non-PCI systems, so allow
> > > > > > either platform or OF based probing.
> > > > > >
> > > > > > Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxx>
> >
> > [snip]
> >
> > > > > > +properties:
> > > > > > +  "#pwm-cells":
> > > > > > +    description: |
> > > > > > +      See pwm.yaml in this directory for a description of the cells format.
> > > > >
> > > > > pwm.yaml doesn't define how many cells. You need to. And you don't need
> > > > > generic descriptions.
> > > >
> > > >    "#pwm-cells":
> > > >       const: 1
> > > >
> > > > should be sufficient then?
> > >
> > > I would expect a value of (at least) 2 or (better) 3.
> >
> > OOPS, forgot the phandle.
> >
> > I will have to check if we have any support yet for dealing
> > with any of the pwm flags yet.
>
> I didn't double check, but given that the driver only supports inversed
> polarity it might not even work without passing the flag for inversed
> polarity. Having said that, I expect you have to only add "#pwm-cells =
> <3>;" to your dts and then everything should work just fine.

I hadn't noticed, but we've been testing with the sysfs interface
as we're using qemu.