p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

media: vidioc-dqevent.rst: clarify V4L2_EVENT_SRC_CH_RESOLUTION 

Clarify that when you receive V4L2_EVENT_SOURCE_CHANGE with flag
V4L2_EVENT_SRC_CH_RESOLUTION set, and the new resolution appears
identical to the old resolution, then you still must restart the
streaming I/O.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This commit is contained in:
Hans Verkuil 2018-09-17 07:37:18 -04:00 committed by Mauro Carvalho Chehab
parent 85e4af0a7a
commit 1611c686c1
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/media/uapi/v4l/vidioc-dqevent.rst
View File

@ -379,7 +379,17 @@ call.
- 0x0001
- This event gets triggered when a resolution change is detected at
an input. This can come from an input connector or from a video
decoder.
decoder. Applications will have to query the new resolution (if
any, the signal may also have been lost).
*Important*: even if the new video timings appear identical to the old
ones, receiving this event indicates that there was an issue with the
video signal and you must stop and restart streaming
(:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>`
followed by :ref:`VIDIOC_STREAMON <VIDIOC_STREAMON>`). The reason is
that many devices are not able to recover from a temporary loss of
signal and so restarting streaming I/O is required in order for the
hardware to synchronize to the video signal.
Return Value