Re: [PATCH v2 2/8] dt-bindings: iio: adc: adi,ad4030: Reference spi-peripheral-props

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 19 Sep 2025 16:53:09 -0300
Marcelo Schmitt <marcelo.schmitt1@gmail.com> wrote:

> On 09/19, Conor Dooley wrote:
> > On Thu, Sep 18, 2025 at 02:39:01PM -0500, David Lechner wrote:  
> > > On 9/18/25 12:38 PM, Marcelo Schmitt wrote:  
> > > > AD4030 and similar devices all connect to the system as SPI peripherals.
> > > > Reference spi-peripheral-props so common SPI peripheral can be used from
> > > > ad4030 dt-binding.
> > > > 
> > > > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> > > > ---
> > > >  Documentation/devicetree/bindings/iio/adc/adi,ad4030.yaml | 2 ++  
> ...
> > > > @@ -20,6 +20,8 @@ description: |
> > > >    * https://www.analog.com/media/en/technical-documentation/data-sheets/ad4630-24_ad4632-24.pdf
> > > >    * https://www.analog.com/media/en/technical-documentation/data-sheets/ad4630-16-4632-16.pdf
> > > >  
> > > > +$ref: /schemas/spi/spi-peripheral-props.yaml#  
> > > 
> > > I think this is already referenced for all child nodes of a SPI
> > > controller because of pattern matching of:
> > > 
> > > patternProperties:
> > >   "^.*@[0-9a-f]+$":
> > >     type: object
> > >     $ref: spi-peripheral-props.yaml
> > > 
> > > in Documentation/devicetree/bindings/spi/spi-controller.yaml
> > > 
> > > So perhaps not strictly necessary?
> > > 
> > > Would be curious to know if there is some difference.  
> > 
> > I think it's good form if you're actually referencing the properties. I
> > don't know if it actually makes a difference in the end result of
> > dtbs_check but it may in terms of making sure properties in this binding
> > are properly typed when it is tested against. In this case, it appears
> > you're only looking at uint32 properties so it mightn't have any impact.
> > Rob would know for sure.
> >   
> 
> There's no difference, at least on dt_binding_check output.
> Initial idea was to allow using properties from spi-peripheral-props.yaml, but
> they are already available through the pattern in spi-controller.yaml.
> If the noise doesn't worth it, I don't mind dropping this patch.
> 
I agree with Conor. Having this here might not be strictly necessary but it
helps a reader of this binding know that those properties are relevant.
So I think keep it.

Jonathan

> Thanks,
> Marcelo