ipa: simple: softisp: Extend to pass metadata

Extend the Simple IPA IPC to support returning a metadata ControlList
when the process call has completed.

A new signal from the IPA is introduced to report the metadata,
similarly to what the hardware pipelines do.

Merge the metadata reported by the ISP into any completing request to
provide to the application.  Completion of a request is delayed until
this is done; this doesn't apply to canceled requests.

Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

include/libcamera/internal/software_isp/software_isp.h

@@ -85,6 +85,7 @@ public:
 	Signal<FrameBuffer *> inputBufferReady;
 	Signal<FrameBuffer *> outputBufferReady;
 	Signal<uint32_t, uint32_t> ispStatsReady;
+	Signal<uint32_t, const ControlList &> metadataReady;
 	Signal<const ControlList &> setSensorControls;
 
 private:

include/libcamera/ipa/soft.mojom

@@ -33,4 +33,5 @@ interface IPASoftInterface {
 interface IPASoftEventInterface {
 	setSensorControls(libcamera.ControlList sensorControls);
 	setIspParams();
+	metadataReady(uint32 frame, libcamera.ControlList metadata);
 };

src/ipa/simple/soft_simple.cpp

@@ -299,15 +299,10 @@ void IPASoftSimple::processStats(const uint32_t frame,
 	int32_t again = sensorControls.get(V4L2_CID_ANALOGUE_GAIN).get<int32_t>();
 	frameContext.sensor.gain = camHelper_ ? camHelper_->gain(again) : again;
 
-	/*
-	 * Software ISP currently does not produce any metadata. Use an empty
-	 * ControlList for now.
-	 *
-	 * \todo Implement proper metadata handling
-	 */
 	ControlList metadata(controls::controls);
 	for (auto const &algo : algorithms())
 		algo->process(context_, frame, frameContext, stats_, metadata);
+	metadataReady.emit(frame, metadata);
 
 	/* Sanity check */
 	if (!sensorControls.contains(V4L2_CID_EXPOSURE) ||

src/libcamera/pipeline/simple/simple.cpp

@@ -182,19 +182,21 @@ LOG_DEFINE_CATEGORY(SimplePipeline)
 class SimplePipelineHandler;
 
 struct SimpleFrameInfo {
-	SimpleFrameInfo(uint32_t f, Request *r)
-		: frame(f), request(r)
+	SimpleFrameInfo(uint32_t f, Request *r, bool m)
+		: frame(f), request(r), metadataRequired(m), metadataProcessed(false)
 	{
 	}
 
 	uint32_t frame;
 	Request *request;
+	bool metadataRequired;
+	bool metadataProcessed;
 };
 
 class SimpleFrames
 {
 public:
-	void create(Request *request);
+	void create(Request *request, bool metadataRequested);
 	void destroy(uint32_t frame);
 	void clear();
 
@@ -204,10 +206,10 @@ private:
 	std::map<uint32_t, SimpleFrameInfo> frameInfo_;
 };
 
-void SimpleFrames::create(Request *request)
+void SimpleFrames::create(Request *request, bool metadataRequired)
 {
 	const uint32_t frame = request->sequence();
-	auto [it, inserted] = frameInfo_.try_emplace(frame, frame, request);
+	auto [it, inserted] = frameInfo_.try_emplace(frame, frame, request, metadataRequired);
 	ASSERT(inserted);
 }
 
@@ -347,11 +349,12 @@ private:
 	void tryPipeline(unsigned int code, const Size &size);
 	static std::vector<const MediaPad *> routedSourcePads(MediaPad *sink);
 
-	void completeRequest(Request *request);
+	void tryCompleteRequest(Request *request);
 	void conversionInputDone(FrameBuffer *buffer);
 	void conversionOutputDone(FrameBuffer *buffer);
 
 	void ispStatsReady(uint32_t frame, uint32_t bufferId);
+	void metadataReady(uint32_t frame, const ControlList &metadata);
 	void setSensorControls(const ControlList &sensorControls);
 };
 
@@ -590,6 +593,7 @@ int SimpleCameraData::init()
 			swIsp_->inputBufferReady.connect(this, &SimpleCameraData::conversionInputDone);
 			swIsp_->outputBufferReady.connect(this, &SimpleCameraData::conversionOutputDone);
 			swIsp_->ispStatsReady.connect(this, &SimpleCameraData::ispStatsReady);
+			swIsp_->metadataReady.connect(this, &SimpleCameraData::metadataReady);
 			swIsp_->setSensorControls.connect(this, &SimpleCameraData::setSensorControls);
 		}
 	}
@@ -835,7 +839,7 @@ void SimpleCameraData::imageBufferReady(FrameBuffer *buffer)
 			/* No conversion, just complete the request. */
 			Request *request = buffer->request();
 			pipe->completeBuffer(request, buffer);
-			completeRequest(request);
+			tryCompleteRequest(request);
 			return;
 		}
 
@@ -853,7 +857,10 @@ void SimpleCameraData::imageBufferReady(FrameBuffer *buffer)
 		const RequestOutputs &outputs = conversionQueue_.front();
 		for (auto &[stream, buf] : outputs.outputs)
 			pipe->completeBuffer(outputs.request, buf);
-		completeRequest(outputs.request);
+		SimpleFrameInfo *info = frameInfo_.find(outputs.request->sequence());
+		if (info)
+			info->metadataRequired = false;
+		tryCompleteRequest(outputs.request);
 		conversionQueue_.pop();
 
 		return;
@@ -911,7 +918,7 @@ void SimpleCameraData::imageBufferReady(FrameBuffer *buffer)
 
 	/* Otherwise simply complete the request. */
 	pipe->completeBuffer(request, buffer);
-	completeRequest(request);
+	tryCompleteRequest(request);
 }
 
 void SimpleCameraData::clearIncompleteRequests()
@@ -922,14 +929,20 @@ void SimpleCameraData::clearIncompleteRequests()
 	}
 }
 
-void SimpleCameraData::completeRequest(Request *request)
+void SimpleCameraData::tryCompleteRequest(Request *request)
 {
+	if (request->hasPendingBuffers())
+		return;
+
 	SimpleFrameInfo *info = frameInfo_.find(request->sequence());
 	if (!info) {
 		/* Something is really wrong, let's return. */
 		return;
 	}
 
+	if (info->metadataRequired && !info->metadataProcessed)
+		return;
+
 	frameInfo_.destroy(info->frame);
 	pipe()->completeRequest(request);
 }
@@ -947,7 +960,7 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer)
 	/* Complete the buffer and the request. */
 	Request *request = buffer->request();
 	if (pipe->completeBuffer(request, buffer))
-		completeRequest(request);
+		tryCompleteRequest(request);
 }
 
 void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId)
@@ -956,6 +969,17 @@ void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId)
 			     delayedCtrls_->get(frame));
 }
 
+void SimpleCameraData::metadataReady(uint32_t frame, const ControlList &metadata)
+{
+	SimpleFrameInfo *info = frameInfo_.find(frame);
+	if (!info)
+		return;
+
+	info->request->metadata().merge(metadata);
+	info->metadataProcessed = true;
+	tryCompleteRequest(info->request);
+}
+
 void SimpleCameraData::setSensorControls(const ControlList &sensorControls)
 {
 	delayedCtrls_->push(sensorControls);
@@ -1489,7 +1513,7 @@ int SimplePipelineHandler::queueRequestDevice(Camera *camera, Request *request)
 		}
 	}
 
-	data->frameInfo_.create(request);
+	data->frameInfo_.create(request, !!data->swIsp_);
 	if (data->useConversion_) {
 		data->conversionQueue_.push({ request, std::move(buffers) });
 		if (data->swIsp_)

src/libcamera/software_isp/software_isp.cpp

@@ -55,6 +55,11 @@ LOG_DEFINE_CATEGORY(SoftwareIsp)
  * \brief A signal emitted when the statistics for IPA are ready
  */
 
+/**
+ * \var SoftwareIsp::metadataReady
+ * \brief A signal emitted when the metadata for IPA is ready
+ */
+
 /**
  * \var SoftwareIsp::setSensorControls
  * \brief A signal emitted when the values to write to the sensor controls are
@@ -141,6 +146,10 @@ SoftwareIsp::SoftwareIsp(PipelineHandler *pipe, const CameraSensor *sensor,
 	}
 
 	ipa_->setIspParams.connect(this, &SoftwareIsp::saveIspParams);
+	ipa_->metadataReady.connect(this,
+				    [this](uint32_t frame, const ControlList &metadata) {
+					    metadataReady.emit(frame, metadata);
+				    });
 	ipa_->setSensorControls.connect(this, &SoftwareIsp::setSensorCtrls);
 
 	debayer_->moveToThread(&ispWorkerThread_);