An attempt to get a BUTTON control returns EACCES, not EINVAL. BUTTON controls have V4L2_CTRL_FLAG_WRITE_ONLY set, and the documentation for that flag correctly says that getting a write-only control returns EACCES. It's the description of the BUTTON type that's wrong, so fix that so they are consistent. Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> --- diff --git a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst index 6690928e657b..22ff3c6abd9c 100644 --- a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst +++ b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst @@ -378,7 +378,7 @@ See also the examples in :ref:`control`. - 0 - 0 - A control which performs an action when set. Drivers must ignore - the value passed with ``VIDIOC_S_CTRL`` and return an ``EINVAL`` error + the value passed with ``VIDIOC_S_CTRL`` and return an ``EACCES`` error code on a ``VIDIOC_G_CTRL`` attempt. * - ``V4L2_CTRL_TYPE_INTEGER64`` - any