Document the requirement of notifying to userspace the possible re-ordering of the color sample components when a vertical or horizontal flip is applied to a RAW camera sensor. Signed-off-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx> --- Documentation/driver-api/media/camera-sensor.rst | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Documentation/driver-api/media/camera-sensor.rst b/Documentation/driver-api/media/camera-sensor.rst index 93f4f2536c25..ee4a7fe5f72a 100644 --- a/Documentation/driver-api/media/camera-sensor.rst +++ b/Documentation/driver-api/media/camera-sensor.rst @@ -173,3 +173,19 @@ V4L2_CID_VFLIP controls with the values programmed by the register sequences. The default values of these controls shall be 0 (disabled). Especially these controls shall not be inverted, independently of the sensor's mounting rotation. + +Flip handling for raw camera sensors +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Applying vertical and horizontal flips on raw camera sensors inverts the color +sample reading direction on the sensor's pixel array. This causes the +re-ordering of the color samples on the sensor's output frame. As an example, a +raw camera sensor with a Bayer pattern color filter array and a native RGGB +Bayer order will produce frames with GRBG component ordering when a vertical +flip is applied. Camera sensor drivers where inverting the reading order +direction causes a re-ordering of the color components are requested to register +the ``V4L2_CID_VFLIP`` and ``V4L2_CID_HFLIP`` controls with the +``V4L2_CTRL_FLAG_MODIFY_LAYOUT`` flag enabled to notify userspace that enabling +a flip can potentially change the output buffer content layout. Flips should +also be taken into account when enumerating and handling media bus formats +on the camera sensor source pads. -- 2.40.1
