libcamera: vimc: Report sensor timestamp

Report the sensor's timestamp in the Request metadata using the
completed buffer timestamp.

The buffer's timestamp reports the video capture buffer processing time,
and it does not theoretically matches the 'start of exposure'
definition.

VIMC being a testing platform and the test driver completes the buffers
for each media entity connected in the pipeline one after the other, the
current solution is acceptable for the pipeline.

Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/src/libcamera/pipeline/vimc/vimc.cpp b/src/libcamera/pipeline/vimc/vimc.cpp
index 8f5f4ba3..ce83dcaa 100644
--- a/src/libcamera/pipeline/vimc/vimc.cpp
+++ b/src/libcamera/pipeline/vimc/vimc.cpp
@@ -523,6 +523,10 @@ void VimcCameraData::bufferReady(FrameBuffer *buffer)
 {
 	Request *request = buffer->request();
 
+	/* Record the sensor's timestamp in the request metadata. */
+	request->metadata().set(controls::SensorTimestamp,
+				buffer->metadata().timestamp);
+
 	pipe_->completeBuffer(request, buffer);
 	pipe_->completeRequest(request);
 }