android: camera_device: Report pipeline depth

Report the pipeline depth in the capture results if the pipeline
reports it.

Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

src/android/camera_device.cpp

@@ -675,10 +675,10 @@ std::tuple<uint32_t, uint32_t> CameraDevice::calculateStaticMetadataSize()
 {
 	/*
 	 * \todo Keep this in sync with the actual number of entries.
-	 * Currently: 51 entries, 687 bytes of static metadata
+	 * Currently: 52 entries, 698 bytes of static metadata
 	 */
 	uint32_t numEntries = 52;
-	uint32_t byteSize = 694;
+	uint32_t byteSize = 698;
 
 	/*
 	 * Calculate space occupation in bytes for dynamically built metadata
@@ -1187,6 +1187,7 @@ const camera_metadata_t *CameraDevice::getStaticMetadata()
 		ANDROID_CONTROL_AWB_STATE,
 		ANDROID_CONTROL_AWB_LOCK,
 		ANDROID_LENS_STATE,
+		ANDROID_REQUEST_PIPELINE_DEPTH,
 		ANDROID_SCALER_CROP_REGION,
 		ANDROID_SENSOR_TIMESTAMP,
 		ANDROID_SENSOR_ROLLING_SHUTTER_SKEW,
@@ -1704,7 +1705,7 @@ void CameraDevice::requestComplete(Request *request)
 	 * pipeline handlers) timestamp in the Request itself.
 	 */
 	uint64_t timestamp = buffers.begin()->second->metadata().timestamp;
-	resultMetadata = getResultMetadata(descriptor->frameNumber_, timestamp);
+	resultMetadata = getResultMetadata(descriptor, timestamp);
 
 	/* Handle any JPEG compression. */
 	for (unsigned int i = 0; i < descriptor->numBuffers_; ++i) {
@@ -1822,15 +1823,17 @@ void CameraDevice::notifyError(uint32_t frameNumber, camera3_stream_t *stream)
  * Produce a set of fixed result metadata.
  */
 std::unique_ptr<CameraMetadata>
-CameraDevice::getResultMetadata([[maybe_unused]] int frame_number,
+CameraDevice::getResultMetadata(Camera3RequestDescriptor *descriptor,
 				int64_t timestamp)
 {
+	const ControlList &metadata = descriptor->request_->metadata();
+
 	/*
 	 * \todo Keep this in sync with the actual number of entries.
 	 * Currently: 18 entries, 62 bytes
 	 */
 	std::unique_ptr<CameraMetadata> resultMetadata =
-		std::make_unique<CameraMetadata>(18, 62);
+		std::make_unique<CameraMetadata>(19, 63);
 	if (!resultMetadata->isValid()) {
 		LOG(HAL, Error) << "Failed to allocate static metadata";
 		return nullptr;
@@ -1880,6 +1883,14 @@ CameraDevice::getResultMetadata([[maybe_unused]] int frame_number,
 	resultMetadata->addEntry(ANDROID_STATISTICS_SCENE_FLICKER,
 				 &scene_flicker, 1);
 
+	/* Add metadata tags reported by libcamera. */
+	if (metadata.contains(controls::draft::PipelineDepth)) {
+		uint8_t pipeline_depth =
+			metadata.get<int32_t>(controls::draft::PipelineDepth);
+		resultMetadata->addEntry(ANDROID_REQUEST_PIPELINE_DEPTH,
+					 &pipeline_depth, 1);
+	}
+
 	/*
 	 * Return the result metadata pack even is not valid: get() will return
 	 * nullptr.

src/android/camera_device.h

@@ -105,8 +105,8 @@ private:
 	void notifyError(uint32_t frameNumber, camera3_stream_t *stream);
 	CameraMetadata *requestTemplatePreview();
 	libcamera::PixelFormat toPixelFormat(int format) const;
-	std::unique_ptr<CameraMetadata> getResultMetadata(int frame_number,
+	std::unique_ptr<CameraMetadata> getResultMetadata(
-							  int64_t timestamp);
+		Camera3RequestDescriptor *descriptor, int64_t timestamp);
 
 	unsigned int id_;
 	camera3_device_t camera3Device_;

src/android/camera_worker.h

@@ -25,6 +25,10 @@ public:
 	CaptureRequest(libcamera::Camera *camera, uint64_t cookie);
 
 	const std::vector<int> &fences() const { return acquireFences_; }
+	const libcamera::ControlList &metadata() const
+	{
+		return request_->metadata();
+	}
 
 	void addBuffer(libcamera::Stream *stream,
 		       libcamera::FrameBuffer *buffer, int fence);