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

[David Lechner]

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.