avcodec/v4l2_m2m: handle v4l2 end of stream event

When flushing the capture buffers, the driver may send a V4L2_EVENT_EOS
to notify that draining is completed. Currently, v4l2_m2m does not
subscribe to this event, which can cause some devices (i.e. imx8qm) to
hang at the end of encoding/decoding. Support for handling the event is
added in this commit.

Some devices may not signal V4L2_EVENT_EOS. This is logged as a warning
message during initialization and not treated as a fatal error.

Signed-off-by: Ming Qian <ming.qian@nxp.com>
Signed-off-by: Andriy Gelman <andriy.gelman@gmail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/libavcodec/v4l2_context.c b/libavcodec/v4l2_context.c
index 31af10d28e..6c2db5c849 100644
--- a/libavcodec/v4l2_context.c
+++ b/libavcodec/v4l2_context.c
@@ -154,6 +154,7 @@ static inline void v4l2_save_to_context(V4L2Context* ctx, struct v4l2_format_upd
 }
 
 /**
+ * handle resolution change event and end of stream event
  * returns 1 if reinit was successful, negative if it failed
  * returns 0 if reinit was not executed
  */
@@ -171,6 +172,11 @@ static int v4l2_handle_event(V4L2Context *ctx)
         return 0;
     }
 
+    if (evt.type == V4L2_EVENT_EOS) {
+        ctx->done = 1;
+        return 0;
+    }
+
     if (evt.type != V4L2_EVENT_SOURCE_CHANGE)
         return 0;