Re: [PATCH v3 1/3] dt-bindings: iio: adc: sophgo,cv18xx-saradc.yaml: Add Sophgo SARADC binding documentation

From: Inochi Amaoto
Date: Wed Jul 31 2024 - 18:40:17 EST


On Wed, Jul 31, 2024 at 04:48:01PM GMT, Thomas Bonnefille wrote:
>
>
> On 7/31/24 2:41 PM, Inochi Amaoto wrote:
> > On Wed, Jul 31, 2024 at 02:24:14PM GMT, Thomas Bonnefille wrote:
> > > The Sophgo SARADC is a Successive Approximation ADC that can be found in
> > > the Sophgo SoC.
> > >
> > > Signed-off-by: Thomas Bonnefille <thomas.bonnefille@xxxxxxxxxxx>
> > > ---
> > > .../bindings/iio/adc/sophgo,cv18xx-saradc.yaml | 48 ++++++++++++++++++++++
> > > 1 file changed, 48 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/iio/adc/sophgo,cv18xx-saradc.yaml b/Documentation/devicetree/bindings/iio/adc/sophgo,cv18xx-saradc.yaml
> > > new file mode 100644
> > > index 000000000000..79d8cb52279f
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/iio/adc/sophgo,cv18xx-saradc.yaml
> > > @@ -0,0 +1,48 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/iio/adc/sophgo,cv18xx-saradc.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title:
> > > + Sophgo CV18XX SoC series 3 channels Successive Approximation Analog to
> > > + Digital Converters
> > > +
> > > +maintainers:
> > > + - Thomas Bonnefille <thomas.bonnefille@xxxxxxxxxxx>
> > > +
> > > +description:
> > > + Datasheet at https://github.com/sophgo/sophgo-doc/releases
> > > +
> > > +properties:
> > > + compatible:
> > > + oneOf:
> > > + - items:
> > > + - const: sophgo,cv1800b-saradc
> >
> > There is no need to use "oneOF" and "items"
> >
>
> Thank you very much, I'll do that.
>
> > Suggestions: add a compatible like "cv1800-saradc" as fallback
> > and add use "sophgo,cv1800b-saradc" as specific compatible.
> > Use the "cv1800-saradc" in the cv18xx.dtsi and override the
> > compatible with specific one if necessary.
> >
>
> If I understand correctly, maintainers doesn't want the use of wildcards as
> generic compatibles [1]. They prefer to use the most basic SoC as the
> generic compatible.
> Is the CV1800 a real SoC or is it just a kind of wildcard to say CV18* ?

Yeah, that is the wildcard too.

>
> > For example:
> > - items:
> > - enum:
> > - sophgo,cv1800b-saradc
> > - const: sophgo,cv1800-saradc
> > - const: sophgo,cv1800b-saradc
> >
>
> To avoid the issue of falling back on a wildcard I planned to do this
> instead:
> properties:
> compatible:
> const: sophgo,cv1800b-saradc
>

I have read the link, it seems the upstream may prefer this solution.
Let's use cv1800b as the basic fallback.

>
>
> > Regards,
> > Inochi
>
> [1] : https://lore.kernel.org/all/20240708165719.000021b9@xxxxxxxxxx/
>
> Thank you for your comments :)
> Thomas