media: vimc: streamer: if kthread_stop fails, ignore the error

Ignore errors returned from kthread_stop since the
vimc subdevices should still be notified that
streaming stopped so they can release the memory for
the streaming, and also kthread should be set to NULL.
kthread_stop can return -EINTR in case the thread
did not yet run. This can happen if userspace calls
streamon and streamoff right after.

Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/vimc/vimc-streamer.c

@@ -220,8 +220,14 @@ int vimc_streamer_s_stream(struct vimc_stream *stream,
 			return 0;
 
 		ret = kthread_stop(stream->kthread);
+		/*
+		 * kthread_stop returns -EINTR in cases when streamon was
+		 * immediately followed by streamoff, and the thread didn't had
+		 * a chance to run. Ignore errors to stop the stream in the
+		 * pipeline.
+		 */
 		if (ret)
-			return ret;
+			dev_dbg(ved->dev, "kthread_stop returned '%d'\n", ret);
 
 		stream->kthread = NULL;