On Mon, 31 Aug 2020 20:00:17 -0700 Gwendal Grignou <gwendal@xxxxxxxxxxxx> wrote: > Some sensors/sensorhubs can calculate drift or hard iron offsets to > apply to raw data to get the true measure data. > These offsets are applied by the user space application. > When these offsets change, events are raised to tell the application > to update the cached offset values. > > Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx> I'm fine with this, but would like to give a bit more time for others to comment. Also you left the version number as wild cards. I guess I can fix that, but I've been known to miss such things so better to be optimistic and put in 5.10. However I don't really want to see ABI without a user so I'd rather see this patch alongside the driver update. Thanks, Jonathan > --- > Changes since v1: > - Define metadata_en instead of offset/scale_en to limit race > conditions. > 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 f77aee8886c66..45f456de1621a 100644 > --- a/Documentation/ABI/testing/sysfs-bus-iio > +++ b/Documentation/ABI/testing/sysfs-bus-iio > @@ -1735,3 +1735,16 @@ Contact: linux-iio@xxxxxxxxxxxxxxx > Description: > Hard Iron bias calculated by the sensor or sensorhub. To be applied by > user space application to the raw data to obtain the geomagnetic field. > + > +What: /sys/.../iio:deviceX/events/in_accel_metadata_change_en > +What: /sys/.../iio:deviceX/events/in_magn_metadata_change_en > +What: /sys/.../iio:deviceX/events/in_anglvel_metadata_change_en I've just been looking at existing naming of events and thinking about whether we should have a space between metadata and change. From a human readabilty point of view it would be nice, but from a parsability viewpoint possibly not. We do have precedent though for such a space (even if we wouldn't have done it today) in thresh_adaptive and mag_adaptive (see industrialio-event.c) so I guess one more probably doesn't hurt too much. > +KernelVersion: x.y Be an optimist for patches like this and put the next cycle in there. That's better than some maintainers just picking it up with wild cards :) > +Contact: linux-iio@xxxxxxxxxxxxxxx > +Description: > + Some sensors internally calculate offset to apply to remove bias (for > + instance, hard/soft-iron bias for magnetometer, online calibration bias for > + gyroscope or accelerometer). > + When the sensor computes a new set of offset values, it generates an > + event for the userspace application to refresh the offsets to apply to raw > + data.
