Re: [PATCH v2 1/2] dt-bindings: iio: adc: ti,ads1015: Add label property

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 3 Sep 2026 10:30:01 -0500
David Lechner <dlechner@baylibre.com> wrote:

> On 9/3/26 10:19 AM, Flaviu Nistor wrote:
> > On Wed, Sep 2, 2026 at 9:31 PM, David Lechner wrote:  
> >> On 9/2/26 12:22 PM, Flaviu Nistor wrote:  
> >>> Add support for an optional label property per channel similar to other adc
> >>> chips. This allows assigning distinct names for each channel which can
> >>> match the schematic signal name.
> >>>
> >>> Signed-off-by: Flaviu Nistor <flaviu.nistor@gmail.com>
> >>> ---
> >>>  Documentation/devicetree/bindings/iio/adc/ti,ads1015.yaml | 6 ++++++
> >>>  1 file changed, 6 insertions(+)
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/iio/adc/ti,ads1015.yaml b/Documentation/devicetree/bindings/iio/adc/ti,ads1015.yaml
> >>> index 718f633c6e04..777a75c21d7f 100644
> >>> --- a/Documentation/devicetree/bindings/iio/adc/ti,ads1015.yaml
> >>> +++ b/Documentation/devicetree/bindings/iio/adc/ti,ads1015.yaml
> >>> @@ -66,6 +66,11 @@ patternProperties:
> >>>            - minimum: 0
> >>>              maximum: 7
> >>>  
> >>> +      label:
> >>> +        $ref: /schemas/types.yaml#/definitions/string
> >>> +        description:
> >>> +          A descriptive name for this channel, like "vcc_ram" or "CH3".
> >>> +  
> >>
> >> Apparently this chip has quite old dt-bindings. Normally, we would have
> >> included adc.yaml to get this and other channel properties.

Quite a lot of bindings predate that generalization work :(

> >>
> >> And we would have used diff-channels and single-channel from that to
> >> describe which pins are associated with which channel rather than having
> >> a magic number for reg. And the ti,datarate looks suspicious as sampling
> >> frequency is usually we control at runtime.
> >>
> >> Anyway, none of that is really relevant to this patch. We'll see what
> >> Jonathan says about using adc.yaml here vs. adding a label property.

Given it's only a single property and label is pretty universal
I'm fine with just adding it here without the reference to adc.yaml.

DT binding reviewers may disagree however!

J

> >>  
> > 
> > Thanks for your feedback. I can also use:
> > 
> > $ref: adc.yaml
> > unevaluatedProperties: false
> > 
> > and move additionalProperties: false at the end of patternProperties block.  
> 
> It can't have both unevaluatedProperties and additionalProperties (hopefully
> the dt_binding_check would catch that).
> 
> > Any other idea?
> > 
> > Best regards,
> > Flaviu Nistor
> >   
> >>>        ti,gain:
> >>>          $ref: /schemas/types.yaml#/definitions/uint32
> >>>          minimum: 0
> >>> @@ -125,6 +130,7 @@ examples:
> >>>                  reg = <4>;
> >>>                  ti,gain = <3>;
> >>>                  ti,datarate = <5>;
> >>> +                label = "CH3";
> >>>              };
> >>>          };
> >>>      };  
>