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-rw-r--r--Documentation/media/uapi/v4l/buffer.rst29
1 files changed, 26 insertions, 3 deletions
diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst
index e2c85ddc990b..2e266d32470a 100644
--- a/Documentation/media/uapi/v4l/buffer.rst
+++ b/Documentation/media/uapi/v4l/buffer.rst
@@ -306,10 +306,23 @@ struct v4l2_buffer
- A place holder for future extensions. Drivers and applications
must set this to 0.
* - __u32
- - ``reserved``
+ - ``request_fd``
-
- - A place holder for future extensions. Drivers and applications
- must set this to 0.
+ - The file descriptor of the request to queue the buffer to. If the flag
+ ``V4L2_BUF_FLAG_REQUEST_FD`` is set, then the buffer will be
+ queued to this request. If the flag is not set, then this field will
+ be ignored.
+
+ The ``V4L2_BUF_FLAG_REQUEST_FD`` flag and this field are only used by
+ :ref:`ioctl VIDIOC_QBUF <VIDIOC_QBUF>` and ignored by other ioctls that
+ take a :c:type:`v4l2_buffer` as argument.
+
+ Applications should not set ``V4L2_BUF_FLAG_REQUEST_FD`` for any ioctls
+ other than :ref:`VIDIOC_QBUF <VIDIOC_QBUF>`.
+
+ If the device does not support requests, then ``EACCES`` will be returned.
+ If requests are supported but an invalid request file descriptor is
+ given, then ``EINVAL`` will be returned.
@@ -514,6 +527,11 @@ Buffer Flags
streaming may continue as normal and the buffer may be reused
normally. Drivers set this flag when the ``VIDIOC_DQBUF`` ioctl is
called.
+ * .. _`V4L2-BUF-FLAG-IN-REQUEST`:
+
+ - ``V4L2_BUF_FLAG_IN_REQUEST``
+ - 0x00000080
+ - This buffer is part of a request that hasn't been queued yet.
* .. _`V4L2-BUF-FLAG-KEYFRAME`:
- ``V4L2_BUF_FLAG_KEYFRAME``
@@ -589,6 +607,11 @@ Buffer Flags
the format. Any Any subsequent call to the
:ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` ioctl will not block anymore,
but return an ``EPIPE`` error code.
+ * .. _`V4L2-BUF-FLAG-REQUEST-FD`:
+
+ - ``V4L2_BUF_FLAG_REQUEST_FD``
+ - 0x00800000
+ - The ``request_fd`` field contains a valid file descriptor.
* .. _`V4L2-BUF-FLAG-TIMESTAMP-MASK`:
- ``V4L2_BUF_FLAG_TIMESTAMP_MASK``