Re: [PATCH 2/6] dt-bindings: iio: adc: ad7380: fix ad7380-4 reference supply

Julien Stephan
2024-10-15T09:11:03Z

Le lun. 14 oct. 2024 à 20:37, Jonathan Cameron <jic23@kernel.org> a écrit :
>
> On Mon, 14 Oct 2024 11:00:39 +0200
> Julien Stephan <jstephan@baylibre.com> wrote:
>
> > Le jeu. 10 oct. 2024 à 20:22, Jonathan Cameron <jic23@kernel.org> a écrit :
> > >
> > > On Tue, 8 Oct 2024 09:52:50 +0200
> > > Krzysztof Kozlowski <krzk@kernel.org> wrote:
> > >
> > > > On Mon, Oct 07, 2024 at 05:45:45PM +0200, Julien Stephan wrote:
> > > > > ad7380-4 is the only device from ad738x family that doesn't have an
> > > > > internal reference. Moreover its external reference is called REFIN in
> > > > > the datasheet while all other use REFIO as an optional external
> > > > > reference. If refio-supply is omitted the internal reference is
> > > > > used.
> > > > >
> > > > > Fix the binding by adding refin-supply and makes it required for
> > > > > ad7380-4 only.
> > > >
> > > > Maybe let's just use refio as refin? Reference-IO fits here well.
> > > > Otherwise you have two supplies for the same.
> > > Whilst it is ugly, the effort this series is going to in order
> > > to paper over a naming mismatch makes me agree with Krzysztof.
> > >
> > > I think adding a comment to the dt-binding would be sensible
> > > though as people might fall into this hole.
> > >
> >
> > Hi Jonathan and Krzysztof,
> >
> > I am currently adding support for another chip to this family
> > (ADAQ4380-4) and it also uses REFIN.. but in another way ad7380-4
> > does..
> > So:
> > - ad7380-4 does not have any internal reference and use a mandatory
> > refin supply as external reference
> > - adaq4380-4 does not have external reference but uses a 3V internal
> > reference derived from a 5V mandatory refin supply
> > - all others (AFAIK) use an optional refio external reference. If
> > omitted, use an internal 2.5V reference.
> >
> > I am not sure using a single refio-supply for all will make things
> > clearer.. What do you think? Should I also send the adaq series now to
> > bring more context? (I wanted feedback on this series first).
> >
>
> Sounds like that context would be useful if you have it more or less
> ready to send anyway. I don't have particularly strong views on this
> either way. If we 'fix' the case you have here, old bindings should
> continue to work for the part you are moving over (though no need
> to have them in the dt-bindings file).
>

Hi Jonathan,

Just sent the new series with an RFC tag.

Cheers
Julien

> Jonathan
>
> > Cheers
> > Julien
> >
> > > Other than the missing ret =, rest of series looks fine to me
> > >
> > > Jonathan
> > >
> > > >
> > > > Best regards,
> > > > Krzysztof
> > > >
> > >
>