From: Francesco Lavra Date: Tue, 24 Mar 2026 08:47:59 +0000 (+0100) Subject: iio: ABI: Add quaternion axis modifier X-Git-Tag: v7.2-rc1~67^2~5^2~255 X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=dd59392a3ec23dbe3a3fabadcf3bb847e9592ccd;p=thirdparty%2Flinux.git iio: ABI: Add quaternion axis modifier This modifier applies to the IIO_ROT channel type, and indicates a data representation that specifies the {x, y, z} components of the normalized quaternion vector. Signed-off-by: Francesco Lavra Reviewed-by: David Lechner Signed-off-by: Jonathan Cameron --- diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio index 851cfe4f0a05a..60dfeff8f2c95 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio +++ b/Documentation/ABI/testing/sysfs-bus-iio @@ -1755,6 +1755,21 @@ Description: measurement from channel Y. Units after application of scale and offset are milliamps. +What: /sys/bus/iio/devices/iio:deviceX/in_rot_quaternionaxis_raw +KernelVersion: 7.1 +Contact: linux-iio@vger.kernel.org +Description: + Raw value of {x, y, z} components of the quaternion vector. These + components represent the axis about which a rotation occurs, and are + subject to the following constraints: + + - the quaternion vector is normalized, i.e. w^2 + x^2 + y^2 + z^2 = 1 + - the rotation angle is within the [-pi, pi] range, i.e. the w + component (which represents the amount of rotation) is non-negative + + These constraints allow the w value to be calculated from the other + components: w = sqrt(1 - (x^2 + y^2 + z^2)). + What: /sys/.../iio:deviceX/in_energy_en What: /sys/.../iio:deviceX/in_distance_en What: /sys/.../iio:deviceX/in_velocity_sqrt(x^2+y^2+z^2)_en diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 22eefd048ba92..bd6f4f9f45330 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -157,6 +157,7 @@ static const char * const iio_modifier_names[] = { [IIO_MOD_ACTIVE] = "active", [IIO_MOD_REACTIVE] = "reactive", [IIO_MOD_APPARENT] = "apparent", + [IIO_MOD_QUATERNION_AXIS] = "quaternionaxis", }; /* relies on pairs of these shared then separate */ diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h index 6d269b8442713..d7c2bb2236518 100644 --- a/include/uapi/linux/iio/types.h +++ b/include/uapi/linux/iio/types.h @@ -113,6 +113,7 @@ enum iio_modifier { IIO_MOD_ACTIVE, IIO_MOD_REACTIVE, IIO_MOD_APPARENT, + IIO_MOD_QUATERNION_AXIS, }; enum iio_event_type { diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c index 03ca33869ce85..df6c43d7738d6 100644 --- a/tools/iio/iio_event_monitor.c +++ b/tools/iio/iio_event_monitor.c @@ -145,6 +145,7 @@ static const char * const iio_modifier_names[] = { [IIO_MOD_ACTIVE] = "active", [IIO_MOD_REACTIVE] = "reactive", [IIO_MOD_APPARENT] = "apparent", + [IIO_MOD_QUATERNION_AXIS] = "quaternionaxis", }; static bool event_is_known(struct iio_event_data *event)