[media] uvcvideo: Fix clock param realtime setting

timestamps in v4l2 buffers returned to userspace are updated in
uvc_video_clock_update() which uses timestamps fetched from
uvc_video_clock_decode() by calling unconditionally ktime_get_ts().

Hence setting the module clock param to realtime has no effect before
this patch.

This has been tested with ffmpeg:

ffmpeg -y -f v4l2 -input_format yuyv422 -video_size 640x480 -framerate 30 -i /dev/video0 \
 -f alsa -acodec pcm_s16le -ar 16000 -ac 1 -i default \
 -c:v libx264 -preset ultrafast \
 -c:a libfdk_aac \
 out.mkv

and inspecting the v4l2 input starting timestamp.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index ca205eec522389da7cba530d5a8e72506c827fa3..9144a2f3ed826c541ef9d5d1b3286e00ce7c1d6d 100644 (file)
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -361,6 +361,14 @@ static int uvc_commit_video(struct uvc_streaming *stream,
  * Clocks and timestamps
  */
 
+static inline void uvc_video_get_ts(struct timespec *ts)
+{
+       if (uvc_clock_param == CLOCK_MONOTONIC)
+               ktime_get_ts(ts);
+       else
+               ktime_get_real_ts(ts);
+}
+
 static void
 uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf,
                       const __u8 *data, int len)
@@ -420,7 +428,7 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf,
        stream->clock.last_sof = dev_sof;
 
        host_sof = usb_get_current_frame_number(stream->dev->udev);
-       ktime_get_ts(&ts);
+       uvc_video_get_ts(&ts);
 
        /* The UVC specification allows device implementations that can't obtain
         * the USB frame number to keep their own frame counters as long as they
@@ -1011,10 +1019,7 @@ static int uvc_video_decode_start(struct uvc_streaming *stream,
                        return -ENODATA;
                }
 
-               if (uvc_clock_param == CLOCK_MONOTONIC)
-                       ktime_get_ts(&ts);
-               else
-                       ktime_get_real_ts(&ts);
+               uvc_video_get_ts(&ts);
 
                buf->buf.v4l2_buf.sequence = stream->sequence;
                buf->buf.v4l2_buf.timestamp.tv_sec = ts.tv_sec;