libcamera: pipeline: rkisp1: Move start and stop of path to RkISP1Path

Move the start and stop of a path to RkISP1Path. This allows the
importing of buffers to be moved closer the path start/stop simplifying
the code. Also by adding a simple running tracker the error logic in
PipelineHandlerRkISP1 can be simplified as stop() can always be called.

This also removes all external users of RkISP1Path::video_ so it can be
made private.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/libcamera/pipeline/rkisp1/rkisp1.cpp

@@ -770,20 +770,6 @@ int PipelineHandlerRkISP1::allocateBuffers(Camera *camera)
 		data->selfPathStream_.configuration().bufferCount,
 	});
 
-	if (data->mainPathActive_) {
-		ret = mainPath_.video_->importBuffers(
-			data->mainPathStream_.configuration().bufferCount);
-		if (ret < 0)
-			goto error;
-	}
-
-	if (data->selfPathActive_) {
-		ret = selfPath_.video_->importBuffers(
-			data->selfPathStream_.configuration().bufferCount);
-		if (ret < 0)
-			goto error;
-	}
-
 	ret = param_->allocateBuffers(maxCount, &paramBuffers_);
 	if (ret < 0)
 		goto error;
@@ -813,8 +799,6 @@ int PipelineHandlerRkISP1::allocateBuffers(Camera *camera)
 error:
 	paramBuffers_.clear();
 	statBuffers_.clear();
-	mainPath_.video_->releaseBuffers();
-	selfPath_.video_->releaseBuffers();
 
 	return ret;
 }
@@ -845,12 +829,6 @@ int PipelineHandlerRkISP1::freeBuffers(Camera *camera)
 	if (stat_->releaseBuffers())
 		LOG(RkISP1, Error) << "Failed to release stat buffers";
 
-	if (mainPath_.video_->releaseBuffers())
-		LOG(RkISP1, Error) << "Failed to release main path buffers";
-
-	if (selfPath_.video_->releaseBuffers())
-		LOG(RkISP1, Error) << "Failed to release self path buffers";
-
 	return 0;
 }
 
@@ -896,15 +874,12 @@ int PipelineHandlerRkISP1::start(Camera *camera)
 	std::map<unsigned int, IPAStream> streamConfig;
 
 	if (data->mainPathActive_) {
-		ret = mainPath_.video_->streamOn();
+		ret = mainPath_.start();
 		if (ret) {
 			param_->streamOff();
 			stat_->streamOff();
 			data->ipa_->stop();
 			freeBuffers(camera);
-
-			LOG(RkISP1, Error)
-				<< "Failed to start main path " << camera->id();
 			return ret;
 		}
 
@@ -915,18 +890,13 @@ int PipelineHandlerRkISP1::start(Camera *camera)
 	}
 
 	if (data->selfPathActive_) {
-		ret = selfPath_.video_->streamOn();
+		ret = selfPath_.start();
 		if (ret) {
-			if (data->mainPathActive_)
-				mainPath_.video_->streamOff();
-
+			mainPath_.stop();
 			param_->streamOff();
 			stat_->streamOff();
 			data->ipa_->stop();
 			freeBuffers(camera);
-
-			LOG(RkISP1, Error)
-				<< "Failed to start self path " << camera->id();
 			return ret;
 		}
 
@@ -963,21 +933,8 @@ void PipelineHandlerRkISP1::stop(Camera *camera)
 	RkISP1CameraData *data = cameraData(camera);
 	int ret;
 
-	if (data->selfPathActive_) {
-		ret = selfPath_.video_->streamOff();
-		if (ret)
-			LOG(RkISP1, Warning)
-				<< "Failed to stop self path for "
-				<< camera->id();
-	}
-
-	if (data->mainPathActive_) {
-		ret = mainPath_.video_->streamOff();
-		if (ret)
-			LOG(RkISP1, Warning)
-				<< "Failed to stop main path for "
-				<< camera->id();
-	}
+	selfPath_.stop();
+	mainPath_.stop();
 
 	ret = stat_->streamOff();
 	if (ret)

src/libcamera/pipeline/rkisp1/rkisp1_path.cpp

@@ -20,9 +20,9 @@ LOG_DECLARE_CATEGORY(RkISP1)
 
 RkISP1Path::RkISP1Path(const char *name, const Span<const PixelFormat> &formats,
 		       const Size &minResolution, const Size &maxResolution)
-	: video_(nullptr), name_(name), formats_(formats),
+	: name_(name), running_(false), formats_(formats),
 	  minResolution_(minResolution), maxResolution_(maxResolution),
-	  resizer_(nullptr)
+	  resizer_(nullptr), video_(nullptr)
 {
 }
 
@@ -149,6 +149,45 @@ int RkISP1Path::configure(const StreamConfiguration &config,
 	return 0;
 }
 
+int RkISP1Path::start()
+{
+	int ret;
+
+	if (running_)
+		return -EBUSY;
+
+	/* \todo Make buffer count user configurable. */
+	ret = video_->importBuffers(RKISP1_BUFFER_COUNT);
+	if (ret)
+		return ret;
+
+	ret = video_->streamOn();
+	if (ret) {
+		LOG(RkISP1, Error)
+			<< "Failed to start " << name_ << " path";
+
+		video_->releaseBuffers();
+		return ret;
+	}
+
+	running_ = true;
+
+	return 0;
+}
+
+void RkISP1Path::stop()
+{
+	if (!running_)
+		return;
+
+	if (video_->streamOff())
+		LOG(RkISP1, Warning) << "Failed to stop " << name_ << " path";
+
+	video_->releaseBuffers();
+
+	running_ = false;
+}
+
 namespace {
 constexpr Size RKISP1_RSZ_MP_SRC_MIN{ 32, 16 };
 constexpr Size RKISP1_RSZ_MP_SRC_MAX{ 4416, 3312 };

src/libcamera/pipeline/rkisp1/rkisp1_path.h

@@ -45,22 +45,24 @@ public:
 		return video_->exportBuffers(bufferCount, buffers);
 	}
 
+	int start();
+	void stop();
+
 	int queueBuffer(FrameBuffer *buffer) { return video_->queueBuffer(buffer); }
 	Signal<FrameBuffer *> &bufferReady() { return video_->bufferReady; }
 
-	/* \todo Make video private. */
-	V4L2VideoDevice *video_;
-
 private:
 	static constexpr unsigned int RKISP1_BUFFER_COUNT = 4;
 
 	const char *name_;
+	bool running_;
 
 	const Span<const PixelFormat> formats_;
 	const Size minResolution_;
 	const Size maxResolution_;
 
 	V4L2Subdevice *resizer_;
+	V4L2VideoDevice *video_;
 };
 
 class RkISP1MainPath : public RkISP1Path