Re: [PATCH 1/2] dt-bindings: iio: adc: add Texas Instruments TLA 2528

Matti Vaittinen
2025-12-29T08:04:40Z

On 23/12/2025 20:26, David Lechner wrote:
> On 12/23/25 9:55 AM, Maxime Chevallier wrote:
>> The TI TLA 2528 is a simple 8 channel, 12-bit ADC? Add a binding
>
> TLA2528 (no space). Also, why the "?"?
>
>> documentation for it.
>>
>> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
>> ---
>> .../bindings/iio/adc/ti,tla2528.yaml | 48 +++++++++++++++++++
>> 1 file changed, 48 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/iio/adc/ti,tla2528.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/iio/adc/ti,tla2528.yaml b/Documentation/devicetree/bindings/iio/adc/ti,tla2528.yaml
>> new file mode 100644
>> index 000000000000..0ee326d77014
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/adc/ti,tla2528.yaml
>> @@ -0,0 +1,48 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/iio/adc/ti,tla2528.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Texas Instruments TLA2528 8-channel 12bit I2C ADC
>
> 12-bit
>
>> +
>> +maintainers:
>> + - Maxime Chevallier <maxime.chevallier@bootlin.com>
>> +
>> +description: |
>> + 12bit 8-channel I2C ADC.
>
> The title already says this. Either drop it or add new info.
>
> Also, don't need the |.
>
>> +
>> +properties:
>> + compatible:
>> + const: ti,tla2528
>> +
>> + reg:
>> + maxItems: 1
>> +
>> + vref-supply:
>> + description: Supply for 2.35V to 5.5V reference voltage
>
> According the the datasheet, there are AVDD and DVDD supplies.
> Nothing named VREF or REF.
>
> So instead:
>
> avdd-supply: true
> dvdd-supply: true
>
>
> It looks like inputs can also be used as GPIOs, so
>
> gpio-controller: true
> #gpio-cells:
> const: 2
>
> would be appropriate (it doesn't matter if the driver doesn't
> implement it, we know what the correct bindings are).
>
>> +
>> + "#io-channel-cells":
>> + const: 1

I didn't check the data-sheet, but if the pins can be set to be GPIOs or
ADC inputs, then I would require channels to be specified. It's only 8
channels, so always listing channels that are present shouldn't be that
big of a problem - and it should avoid one to add extra properties to
denote channels used for GPIO if GPIOs need to be supported.

Well, I am not insisting this, there are folks that know this stuff
better than I :)

Yours,
-- Matti

---
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

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