Re: [PATCH 1/4] dt-bindings: mfd: ricoh,rn5t618: ADC related nodes and properties

[Rob Herring <robh@kernel.org>]

On Sat, Jul 03, 2021 at 05:02:45PM +0100, Jonathan Cameron wrote:
> On Sat,  3 Jul 2021 10:42:21 +0200
> Andreas Kemnade <andreas@kemnade.info> wrote:
> 
> > Add ADC related nodes and properties. This will allow to wire
> > up ADC channels to consumers, especially to measure input voltages
> > by the power subdevice.
> > 
> > Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
> > ---
> >  .../bindings/mfd/ricoh,rn5t618.yaml           | 53 +++++++++++++++++++
> >  1 file changed, 53 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/mfd/ricoh,rn5t618.yaml b/Documentation/devicetree/bindings/mfd/ricoh,rn5t618.yaml
> > index 032a7fb0b4a7..185f87a14a54 100644
> > --- a/Documentation/devicetree/bindings/mfd/ricoh,rn5t618.yaml
> > +++ b/Documentation/devicetree/bindings/mfd/ricoh,rn5t618.yaml
> > @@ -73,6 +73,48 @@ properties:
> >      description: |
> >        See Documentation/devicetree/bindings/power/power-controller.txt
> >  
> > +  adc:
> > +    type: object
> > +
> > +    properties:
> > +      compatible:
> > +        enum:
> > +          - ricoh,rn5t618-adc
> > +          - ricoh,rc5t619-adc
> > +
> > +      "#io-channel-cells":
> > +        const: 1
> > +
> > +    additionalProperties: false
> > +
> > +    required:
> > +      - compatible
> > +      - "#io-channel-cells"
> 
> Strictly required?  If not used below (where it is optional)
> then why do we require the ADC driver to provided the services?
> 
> I don't mind you leave it as it is though if you prefer - it doesn't
> do any harm!

The device is either a provider or it is not regardless of whether 
there's a consumer, so I prefer this to be required. Also, if a consumer 
is in an overlay, then it is easier if we can rely on #io-channel-cells 
being present already.

Rob