On Sun, 17 May 2026 19:37:48 +0100 Rodrigo Alencar via B4 Relay <[email protected]> wrote:
> From: Rodrigo Alencar <[email protected]> > > Add documentation for a read-only sysfs attribute that allows to expose > parent-child relationships between IIO channels. > > Signed-off-by: Rodrigo Alencar <[email protected]> > --- > Documentation/ABI/testing/sysfs-bus-iio | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-bus-iio > b/Documentation/ABI/testing/sysfs-bus-iio > index 925a33fd309a..399944974e34 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: [email protected] > +Description: > + Read-only attribute containing the label of the parent channel > + 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 > + the physical or logical relationships between them. Perhaps an example would be useful? Otherwise it seems reasonable. One vague concern I have is maybe we end up with a channel that actually has no other existence than as a parent. Image two signals mixed into one. If that mixed signal has nothing to control it wouldn't normally show up in the ABI. I guess we can give it a label though to ensure there is something there (even when not using labels for this!). J > + > What: /sys/bus/iio/devices/iio:deviceX/in_phaseY_raw > KernelVersion: 4.18 > Contact: [email protected] >

