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| author | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2019-10-11 12:32:40 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2019-10-21 13:37:57 +0300 |
| commit | 137272cdf7cc5be835f44216e6003769d1638480 (patch) | |
| tree | d72ddc241e6533e749de7ed65751d1373b48284c /Documentation/media | |
| parent | 4b1d7c2760d26363c497b959a81f8d055ba767c1 (diff) | |
| download | linux-137272cdf7cc5be835f44216e6003769d1638480.tar.xz | |
media: vb2: add V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF
This patch adds support for the V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF
flag.
It also adds a new V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF
capability.
Drivers should set vb2_queue->subsystem_flags to
VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF to indicate support
for this flag.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'Documentation/media')
| -rw-r--r-- | Documentation/media/uapi/v4l/buffer.rst | 13 | ||||
| -rw-r--r-- | Documentation/media/uapi/v4l/vidioc-reqbufs.rst | 6 |
2 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst index 1cbd9cde57f3..9149b57728e5 100644 --- a/Documentation/media/uapi/v4l/buffer.rst +++ b/Documentation/media/uapi/v4l/buffer.rst @@ -607,6 +607,19 @@ Buffer Flags applications shall use this flag for output buffers if the data in this buffer has not been created by the CPU but by some DMA-capable unit, in which case caches have not been used. + * .. _`V4L2-BUF-FLAG-M2M-HOLD-CAPTURE-BUF`: + + - ``V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF`` + - 0x00000200 + - Only valid if ``V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF`` is + set. It is typically used with stateless decoders where multiple + output buffers each decode to a slice of the decoded frame. + Applications can set this flag when queueing the output buffer + to prevent the driver from dequeueing the capture buffer after + the output buffer has been decoded (i.e. the capture buffer is + 'held'). If the timestamp of this output buffer differs from that + of the previous output buffer, then that indicates the start of a + new frame and the previously held capture buffer is dequeued. * .. _`V4L2-BUF-FLAG-LAST`: - ``V4L2_BUF_FLAG_LAST`` diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst index d7faef10e39b..d0c643db477a 100644 --- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst +++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst @@ -125,6 +125,7 @@ aborting or finishing any DMA in progress, an implicit .. _V4L2-BUF-CAP-SUPPORTS-DMABUF: .. _V4L2-BUF-CAP-SUPPORTS-REQUESTS: .. _V4L2-BUF-CAP-SUPPORTS-ORPHANED-BUFS: +.. _V4L2-BUF-CAP-SUPPORTS-M2M-HOLD-CAPTURE-BUF: .. cssclass:: longtable @@ -150,6 +151,11 @@ aborting or finishing any DMA in progress, an implicit - The kernel allows calling :ref:`VIDIOC_REQBUFS` while buffers are still mapped or exported via DMABUF. These orphaned buffers will be freed when they are unmapped or when the exported DMABUF fds are closed. + * - ``V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF`` + - 0x00000020 + - Only valid for stateless decoders. If set, then userspace can set the + ``V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF`` flag to hold off on returning the + capture buffer until the OUTPUT timestamp changes. Return Value ============ |