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_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 };