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@xxxxxxxxx>
---
diff --git a/Documentation/media/uapi/v4l/vidioc-dqevent.rst b/Documentation/media/uapi/v4l/vidioc-dqevent.rst
index cb3565f36793..04416b6943c0 100644
--- a/Documentation/media/uapi/v4l/vidioc-dqevent.rst
+++ b/Documentation/media/uapi/v4l/vidioc-dqevent.rst
@@ -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
