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Diffstat (limited to 'Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst index 981c95df2dec..06c9553ac48f 100644 --- a/Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-selection.rst @@ -53,6 +53,10 @@ function of the crop API, and more, are supported by the selections API. See :ref:`subdev` for more information on how each selection target affects the image processing pipeline inside the subdevice. +If the subdev device node has been registered in read-only mode, calls to +``VIDIOC_SUBDEV_S_SELECTION`` are only valid if the ``which`` field is set to +``V4L2_SUBDEV_FORMAT_TRY``, otherwise an error is returned and the errno +variable is set to ``-EPERM``. Types of selection targets -------------------------- @@ -123,3 +127,7 @@ EINVAL ``pad`` references a non-existing pad, the ``which`` field references a non-existing format, or the selection target is not supported on the given subdev pad. + +EPERM + The ``VIDIOC_SUBDEV_S_SELECTION`` ioctl has been called on a read-only + subdevice and the ``which`` field is set to ``V4L2_SUBDEV_FORMAT_ACTIVE``. |