Re: [PATCH v2 1/7] dt-bindings: iio: adc: Add TI ADS126x ADC family

[Kurt Borja]

On Mon Jun 29, 2026 at 11:43 AM -05, David Lechner wrote:
> On 6/29/26 11:27 AM, Kurt Borja wrote:
>> On Mon Jun 29, 2026 at 9:21 AM -05, David Lechner wrote:
>>> On 6/28/26 2:12 PM, Kurt Borja wrote:
>>>> On Sun Jun 28, 2026 at 10:45 AM -05, David Lechner wrote:
>>>>> On 6/28/26 12:36 AM, Kurt Borja wrote:
>>>>>> The ADS1262 and ADS1263 are 32-bit, 38.4-kSPS delta-sigma ADCs with an
>>>>>> integrated PGA, internal reference, excitation and burn-out current
>>>>>> sources for sensor biasing and diagnostics. The ADS1263 adds a second,
>>>>>> 24-bit delta-sigma ADC (ADC2) for background measurements.
>>>>>>
>>>
>>> ...
>>>
>>>>>> +
>>>>>> +patternProperties:
>>>>>> +  "^channel@[0-9]+$":
>>>>>> +    $ref: /schemas/iio/adc/adc.yaml#
>>>>>> +    unevaluatedProperties: false
>>>>>> +
>>>>>> +    properties:
>>>>>> +      reg:
>>>>>> +        maxItems: 1
>>>>>> +
>>>>>
>>>>> If we want to allow single-ended/pseudo-differential inputs, then we should
>>>>> also allow single-channel (positive pin) and common-mode-channel (negative
>>>>> pin) properties.
>>>>>
>>>>> This will also require additional common-mode-<N>-supply properties to allow
>>>>> for the negative pin connected to something other than GND.
>>>>
>>>> Ah interesting. Why the N though? wouldn't a single supply connected to
>>>> AINCOM be enough here?
>>>
>>> In theory, any AINx could be a common mode input by connecting it to
>>> a constant voltage supply.
>> 
>> Technically yes, but there is a pin named AINCOM intended for this
>> purpose. Can we do a simplification here? I propose having
>> 
>>   common-mode-channel:
>>     /* AINCOM pin */
>>     const: 10
>> 
>> That way we would only need one common-mode-supply. Would that be okay?
>> 
>
> Ideally, we shouldn't limit how the chip can be wired up in the devicetree
> bindings. It doesn't mean that we have to implement everything in the driver
> though.

Makes sense.

I just have a doubt: In the ADS112c14 bindings, is there a specific
reason why you didn't describe common-mode-<N>-supply?

-- 
Thanks,
 ~ Kurt