diff options
Diffstat (limited to 'Documentation/media/uapi/v4l/vidioc-queryctrl.rst')
-rw-r--r-- | Documentation/media/uapi/v4l/vidioc-queryctrl.rst | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst index 8d6e61a..937ce9e 100644 --- a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst +++ b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst @@ -84,7 +84,9 @@ fills the rest of the structure or returns an ``EINVAL`` error code when the :ref:`v4l2_queryctrl <v4l2-queryctrl>` ``minimum`` to ``maximum``, inclusive. -.. note:: It is possible for ``VIDIOC_QUERYMENU`` to return +.. note:: + + It is possible for ``VIDIOC_QUERYMENU`` to return an ``EINVAL`` error code for some indices between ``minimum`` and ``maximum``. In that case that particular menu item is not supported by this driver. Also note that the ``minimum`` value is not necessarily 0. @@ -188,7 +190,9 @@ See also the examples in :ref:`control`. ``_BITMASK``, ``_MENU`` or ``_INTEGER_MENU`` control. Not valid for other types of controls. - .. note:: Drivers reset controls to their default value only when + .. note:: + + Drivers reset controls to their default value only when the driver is first loaded, never afterwards. - .. row 8 @@ -306,7 +310,9 @@ See also the examples in :ref:`control`. ``_BOOLEAN``, ``_BITMASK``, ``_MENU``, ``_INTEGER_MENU``, ``_U8`` or ``_U16`` control. Not valid for other types of controls. - .. note:: Drivers reset controls to their default value only when + .. note:: + + Drivers reset controls to their default value only when the driver is first loaded, never afterwards. - .. row 8 @@ -728,7 +734,9 @@ See also the examples in :ref:`control`. case the hardware calculates the gain value based on the lighting conditions which can change over time. - .. note:: Setting a new value for a volatile control will have no + .. note:: + + Setting a new value for a volatile control will have no effect and no ``V4L2_EVENT_CTRL_CH_VALUE`` will be sent, unless the ``V4L2_CTRL_FLAG_EXECUTE_ON_WRITE`` flag (see below) is also set. Otherwise the new value will just be ignored. |