[PATCH 01/31] staging: bcm2835-camera: Ensure H264 header bytes get a sensible timestamp

[Stefan Wahren]

From: Dave Stevenson <dave.stevenson at raspberrypi.org>

H264 header come from VC with 0 timestamps, which means they get a
strange timestamp when processed with VC/kernel start times,
particularly if used with the inline header option.
Remember the last frame timestamp and use that if set, or otherwise
use the kernel start time.

Link: https://github.com/raspberrypi/linux/issues/1836
Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.org>
---
 .../staging/vc04_services/bcm2835-camera/bcm2835-camera.c  | 14 ++++++++++++--
 .../staging/vc04_services/bcm2835-camera/bcm2835-camera.h  |  2 ++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
index dce6e6d..0c04815 100644
--- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
+++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
@@ -359,7 +359,9 @@ static void buffer_cb(struct vchiq_mmal_instance *instance,
 		}
 	} else {
 		if (dev->capture.frame_count) {
-			if (dev->capture.vc_start_timestamp != -1 && pts) {
+			if (dev->capture.vc_start_timestamp != -1) {
+				buf->vb.vb2_buf.timestamp = ktime_get_ns();
+			} else if (pts) {
 				ktime_t timestamp;
 				s64 runtime_us = pts -
 				    dev->capture.vc_start_timestamp;
@@ -372,8 +374,15 @@ static void buffer_cb(struct vchiq_mmal_instance *instance,
 					 ktime_to_ns(timestamp));
 				buf->vb.vb2_buf.timestamp = ktime_to_ns(timestamp);
 			} else {
-				buf->vb.vb2_buf.timestamp = ktime_get_ns();
+				if (dev->capture.last_timestamp) {
+					buf->vb.vb2_buf.timestamp =
+						dev->capture.last_timestamp;
+				} else {
+					buf->vb.vb2_buf.timestamp =
+						ktime_to_ns(dev->capture.kernel_start_ts);
+				}
 			}
+			dev->capture.last_timestamp = buf->vb.vb2_buf.timestamp;

 			vb2_set_plane_payload(&buf->vb.vb2_buf, 0, length);
 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
@@ -541,6 +550,7 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count)
 			 dev->capture.vc_start_timestamp, parameter_size);

 	dev->capture.kernel_start_ts = ktime_get();
+	dev->capture.last_timestamp = 0;

 	/* enable the camera port */
 	dev->capture.port->cb_ctx = dev;
diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.h b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.h
index 2b5679e..09273b0 100644
--- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.h
+++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.h
@@ -90,6 +90,8 @@ struct bm2835_mmal_dev {
 		s64         vc_start_timestamp;
 		/* Kernel start timestamp for streaming */
 		ktime_t kernel_start_ts;
+		/* Timestamp of last frame */
+		u64		last_timestamp;

 		struct vchiq_mmal_port  *port; /* port being used for capture */
 		/* camera port being used for capture */
--
2.7.4