Re: [PATCH v5 04/13] Documentation: ABI: testing: add parent entry for iio channels

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] Fragile UAPI design using optional, non-unique labels for channel hierarchy.
- [Low] Grammatical error in the ABI documentation description.
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commit f761a355fe0232b081f1443ebe1a92190c5be5cb
Author: Rodrigo Alencar <rodrigo.alencar@analog.com>

Documentation: ABI: testing: add parent entry for iio channels

Add documentation for a read-only sysfs attribute that allows to expose
parent-child relationships between IIO channels.

> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index 925a33fd309af..399944974e34d 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -2118,6 +2118,19 @@ Description:
>  		specific attributes. This is useful for userspace to be able to
>  		better identify an individual channel.
>  
> +What:		/sys/bus/iio/devices/iio:deviceX/in_voltageY_parent
> +What:		/sys/bus/iio/devices/iio:deviceX/out_voltageY_parent
> +What:		/sys/bus/iio/devices/iio:deviceX/in_altvoltageY_parent
> +What:		/sys/bus/iio/devices/iio:deviceX/out_altvoltageY_parent
> +KernelVersion:	7.1
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		Read-only attribute containing the label of the parent channel

Would it be more robust to expose the parent channel's unique sysfs base name
(e.g. in_voltage0) instead of its label?

IIO channel labels are optional strings and are not guaranteed to be unique
within a single device. Relying on them might create an ambiguous UAPI, as
the relationship cannot be exposed at all if a parent channel does not have
a label.

> +		for hierarchical channel relationships. Only present on channels
> +		that have a parent channel with a valid label. This is useful for
> +		userspace to organize channels in tree-like structures that reflects

This isn't a bug, but there is a typo here: "structures that reflects" should
be "structures that reflect".

> +		the physical or logical relationships between them.
> +
>  What:		/sys/bus/iio/devices/iio:deviceX/in_phaseY_raw
>  KernelVersion:	4.18
>  Contact:	linux-iio@vger.kernel.org

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Sashiko AI review · https://sashiko.dev/#/patchset/20260517-ad9910-iio-driver-v5-0-31599c88314a@analog.com?part=4