Re: [PATCH v2 1/3] dt-bindings: iio: adc: sophgo,cv18xx-saradc.yaml: Add Sophgo SARADC binding documentation

Miquel Raynal
2024-07-08T12:23:54Z

Hi Krzysztof,

krzk@kernel.org wrote on Mon, 8 Jul 2024 09:33:04 +0200:

> On 08/07/2024 08:30, Miquel Raynal wrote:
> > Hi Conor,
> >
> >>>>> +properties:
> >>>>> + compatible:
> >>>>> + oneOf:
> >>>>> + - items:
> >>>>> + - enum:
> >>>>> + - sophgo,cv1800b-saradc
> >>>>> + - const: sophgo,cv18xx-saradc
> >>>>
> >>>> I don't think the fallback here makes sense. If there's other devices
> >>>> with a compatible programming model added later, we can fall back to the
> >>>> cv1800b.
> >
> > I'm sorry but isn't this slightly disagreeing with the "writing
> > bindings" doc pointed in v1? It says,
> >
> > * DO use fallback compatibles when devices are the same as or a subset
> > of prior implementations.
> >
> > I believe we fall in the "devices are the same" category, so I would
> > have myself wrote a similar binding here with a compatible matching
> > them all, plus a hardware-implementation-specific compatible as well;
> > just in case.
>
> Fallback from one model to another. There is no "another" model here,
> but wildcard. There is no such device as cv18xx, right?

No there is not. But I don't think there is a "base" model either.
Just multiple SoCs named cv18<something> with apparently the same ADC.

So actually I guess the discussion here is about the wildcard
compatible. It feels strange to me to have no generic compatible either
with a wildcard or with a "base" implementation (because there is
probably none). So I guess the solution here is to just list a single
specific compatible in the end.

Thanks,
Miquèl