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-rw-r--r--Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst26
-rw-r--r--Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst14
2 files changed, 35 insertions, 5 deletions
diff --git a/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst b/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
index 4d56c0528ad7..b8698b85bd80 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
@@ -199,6 +199,10 @@ still cause this situation.
- ``p_area``
- A pointer to a struct :c:type:`v4l2_area`. Valid if this control is
of type ``V4L2_CTRL_TYPE_AREA``.
+ * - struct :c:type:`v4l2_rect` *
+ - ``p_rect``
+ - A pointer to a struct :c:type:`v4l2_rect`. Valid if this control is
+ of type ``V4L2_CTRL_TYPE_RECT``.
* - struct :c:type:`v4l2_ctrl_h264_sps` *
- ``p_h264_sps``
- A pointer to a struct :c:type:`v4l2_ctrl_h264_sps`. Valid if this control is
@@ -334,14 +338,26 @@ still cause this situation.
- Which value of the control to get/set/try.
* - :cspan:`2` ``V4L2_CTRL_WHICH_CUR_VAL`` will return the current value of
the control, ``V4L2_CTRL_WHICH_DEF_VAL`` will return the default
- value of the control and ``V4L2_CTRL_WHICH_REQUEST_VAL`` indicates that
- these controls have to be retrieved from a request or tried/set for
- a request. In the latter case the ``request_fd`` field contains the
+ value of the control, ``V4L2_CTRL_WHICH_MIN_VAL`` will return the minimum
+ value of the control, and ``V4L2_CTRL_WHICH_MAX_VAL`` will return the maximum
+ value of the control. ``V4L2_CTRL_WHICH_REQUEST_VAL`` indicates that
+ the control value has to be retrieved from a request or tried/set for
+ a request. In that case the ``request_fd`` field contains the
file descriptor of the request that should be used. If the device
does not support requests, then ``EACCES`` will be returned.
- When using ``V4L2_CTRL_WHICH_DEF_VAL`` be aware that you can only
- get the default value of the control, you cannot set or try it.
+ When using ``V4L2_CTRL_WHICH_DEF_VAL``, ``V4L2_CTRL_WHICH_MIN_VAL``
+ or ``V4L2_CTRL_WHICH_MAX_VAL`` be aware that you can only get the
+ default/minimum/maximum value of the control, you cannot set or try it.
+
+ Whether a control supports querying the minimum and maximum values using
+ ``V4L2_CTRL_WHICH_MIN_VAL`` and ``V4L2_CTRL_WHICH_MAX_VAL`` is indicated
+ by the ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX`` flag. Most non-compound
+ control types support this. For controls with compound types, the
+ definition of minimum/maximum values are provided by
+ the control documentation. If a compound control does not document the
+ meaning of minimum/maximum value, then querying the minimum or maximum
+ value will result in the error code -EINVAL.
For backwards compatibility you can also use a control class here
(see :ref:`ctrl-class`). In that case all controls have to
diff --git a/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst b/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
index 4d38acafe8e1..3549417c7feb 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
@@ -441,6 +441,16 @@ See also the examples in :ref:`control`.
- n/a
- A struct :c:type:`v4l2_area`, containing the width and the height
of a rectangular area. Units depend on the use case.
+ * - ``V4L2_CTRL_TYPE_RECT``
+ - n/a
+ - n/a
+ - n/a
+ - A struct :c:type:`v4l2_rect`, containing a rectangle described by
+ the position of its top-left corner, the width and the height. Units
+ depend on the use case. Support for ``V4L2_CTRL_WHICH_MIN_VAL`` and
+ ``V4L2_CTRL_WHICH_MAX_VAL`` is optional and depends on the
+ ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX`` flag. See the documentation of
+ the specific control on how to interpret the minimum and maximum values.
* - ``V4L2_CTRL_TYPE_H264_SPS``
- n/a
- n/a
@@ -657,6 +667,10 @@ See also the examples in :ref:`control`.
``dims[0]``. So setting the control with a differently sized
array will change the ``elems`` field when the control is
queried afterwards.
+ * - ``V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX``
+ - 0x1000
+ - This control supports getting minimum and maximum values using
+ vidioc_g_ext_ctrls with V4L2_CTRL_WHICH_MIN/MAX_VAL.
Return Value
============