Re: [PATCH RFC 1/3] dt-bindings: iio: adc: Add reference-source property

[Kurt Borja]

On Fri Jun 19, 2026 at 9:24 AM -05, David Lechner wrote:
> On 6/18/26 7:33 PM, Kurt Borja wrote:
>> Some ADCs have configurable voltage reference sources for each channel.
>> 
>> Signed-off-by: Kurt Borja <kuurtb@xxxxxxxxx>
>> ---
>>  Documentation/devicetree/bindings/iio/adc/adc.yaml | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>> 
>> diff --git a/Documentation/devicetree/bindings/iio/adc/adc.yaml b/Documentation/devicetree/bindings/iio/adc/adc.yaml
>> index b9bc02b5b07a4c..c74c2084fdb68c 100644
>> --- a/Documentation/devicetree/bindings/iio/adc/adc.yaml
>> +++ b/Documentation/devicetree/bindings/iio/adc/adc.yaml
>> @@ -73,6 +73,16 @@ properties:
>>        device design and can interact with other characteristics such as
>>        settling time.
>>  
>> +  reference-source:
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> +    maxItems: 2
>> +    minItems: 1
>> +    description:
>> +      Indicates the voltage reference source or sources for this channel.
>> +
>> +      This array describes either a single reference source or a positive and
>> +      negative reference sources.
>
> Do you actually know of any devices that allow independently selecting
> the positive and negative sources? I don't think I've ever seen anything
> like that.

The ADS1262 allows it, check the REFMUX register. Only ADC1 allows it
though, ADC2 has a single reference select.

Maybe I can get away with only one for both ADCs without restricting too
much.

> Also, this should be string, not uint32.

Sure!

>
>> +
>>  anyOf:
>>    - oneOf:
>>        - required:
>> 

-- 
Thanks,
 ~ Kurt