diff options
Diffstat (limited to 'Documentation/media/uapi/v4l/vidioc-qbuf.rst')
| -rw-r--r-- | Documentation/media/uapi/v4l/vidioc-qbuf.rst | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/Documentation/media/uapi/v4l/vidioc-qbuf.rst b/Documentation/media/uapi/v4l/vidioc-qbuf.rst index dd3f2e069fcb..727238fc2337 100644 --- a/Documentation/media/uapi/v4l/vidioc-qbuf.rst +++ b/Documentation/media/uapi/v4l/vidioc-qbuf.rst @@ -39,14 +39,14 @@ Applications call the ``VIDIOC_QBUF`` ioctl to enqueue an empty The semantics depend on the selected I/O method. To enqueue a buffer applications set the ``type`` field of a struct -:ref:`v4l2_buffer <v4l2-buffer>` to the same buffer type as was -previously used with struct :ref:`v4l2_format <v4l2-format>` ``type`` -and struct :ref:`v4l2_requestbuffers <v4l2-requestbuffers>` ``type``. +:c:type:`v4l2_buffer` to the same buffer type as was +previously used with struct :c:type:`v4l2_format` ``type`` +and struct :c:type:`v4l2_requestbuffers` ``type``. Applications must also set the ``index`` field. Valid index numbers range from zero to the number of buffers allocated with :ref:`VIDIOC_REQBUFS` (struct -:ref:`v4l2_requestbuffers <v4l2-requestbuffers>` ``count``) minus -one. The contents of the struct :ref:`struct v4l2_buffer <v4l2-buffer>` returned +:c:type:`v4l2_requestbuffers` ``count``) minus +one. The contents of the struct :c:type:`struct v4l2_buffer <v4l2_buffer>` returned by a :ref:`VIDIOC_QUERYBUF` ioctl will do as well. When the buffer is intended for output (``type`` is ``V4L2_BUF_TYPE_VIDEO_OUTPUT``, ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``, @@ -56,7 +56,7 @@ for details. Applications must also set ``flags`` to 0. The ``reserved2`` and ``reserved`` fields must be set to 0. When using the :ref:`multi-planar API <planar-apis>`, the ``m.planes`` field must contain a userspace pointer to a filled-in array of struct -:ref:`v4l2_plane <v4l2-plane>` and the ``length`` field must be set +:c:type:`v4l2_plane` and the ``length`` field must be set to the number of elements in that array. To enqueue a :ref:`memory mapped <mmap>` buffer applications set the @@ -70,7 +70,7 @@ To enqueue a :ref:`user pointer <userp>` buffer applications set the ``memory`` field to ``V4L2_MEMORY_USERPTR``, the ``m.userptr`` field to the address of the buffer and ``length`` to its size. When the multi-planar API is used, ``m.userptr`` and ``length`` members of the -passed array of struct :ref:`v4l2_plane <v4l2-plane>` have to be used +passed array of struct :c:type:`v4l2_plane` have to be used instead. When ``VIDIOC_QBUF`` is called with a pointer to this structure the driver sets the ``V4L2_BUF_FLAG_QUEUED`` flag and clears the ``V4L2_BUF_FLAG_MAPPED`` and ``V4L2_BUF_FLAG_DONE`` flags in the @@ -85,7 +85,7 @@ To enqueue a :ref:`DMABUF <dmabuf>` buffer applications set the ``memory`` field to ``V4L2_MEMORY_DMABUF`` and the ``m.fd`` field to a file descriptor associated with a DMABUF buffer. When the multi-planar API is used the ``m.fd`` fields of the passed array of struct -:ref:`v4l2_plane <v4l2-plane>` have to be used instead. When +:c:type:`v4l2_plane` have to be used instead. When ``VIDIOC_QBUF`` is called with a pointer to this structure the driver sets the ``V4L2_BUF_FLAG_QUEUED`` flag and clears the ``V4L2_BUF_FLAG_MAPPED`` and ``V4L2_BUF_FLAG_DONE`` flags in the @@ -100,7 +100,7 @@ device is closed. Applications call the ``VIDIOC_DQBUF`` ioctl to dequeue a filled (capturing) or displayed (output) buffer from the driver's outgoing queue. They just set the ``type``, ``memory`` and ``reserved`` fields of -a struct :ref:`v4l2_buffer <v4l2-buffer>` as above, when +a struct :c:type:`v4l2_buffer` as above, when ``VIDIOC_DQBUF`` is called with a pointer to this structure the driver fills the remaining fields or returns an error code. The driver may also set ``V4L2_BUF_FLAG_ERROR`` in the ``flags`` field. It indicates a @@ -114,7 +114,7 @@ queue. When the ``O_NONBLOCK`` flag was given to the :ref:`open() <func-open>` function, ``VIDIOC_DQBUF`` returns immediately with an ``EAGAIN`` error code when no buffer is available. -The :ref:`struct v4l2_buffer <v4l2-buffer>` structure is specified in +The :c:type:`struct v4l2_buffer <v4l2_buffer>` structure is specified in :ref:`buffer`. |