libcamera: pipeline_handler: Keep track of MediaDevice

Instead of requiring each pipeline handle implementation to keep track
of calling release() on its media devices upon deletion, keep track of
them in the base class. Add a helper that pipeline handlers shall use
to acquire a media device instead of directly interacting with the
DeviceEnumerator.

This also means that pipeline handler implementations do no need to keep
a shared_ptr<> reference to the media devices they store locally as the
PipelineHandler base class will keep a shared_ptr<> reference to all
media devices consumed for the entire lifetime of the pipeline handler
implementation.

Centrally keeping track of media devices will also be beneficial
to implement exclusive access to pipelines across processes.

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

1 files changed, 5 insertions, 11 deletions

diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index b94d742d..b395405c 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -81,7 +81,7 @@ private:
 	int createCamera(MediaEntity *sensor);
 	void bufferReady(Buffer *buffer);
 
-	std::shared_ptr<MediaDevice> media_;
+	MediaDevice *media_;
 	V4L2Subdevice *dphy_;
 	V4L2Subdevice *isp_;
 	V4L2Device *video_;
@@ -100,9 +100,6 @@ PipelineHandlerRkISP1::~PipelineHandlerRkISP1()
 	delete video_;
 	delete isp_;
 	delete dphy_;
-
-	if (media_)
-		media_->release();
 }
 
 /* -----------------------------------------------------------------------------
@@ -355,24 +352,21 @@ bool PipelineHandlerRkISP1::match(DeviceEnumerator *enumerator)
 	dm.add("rkisp1-input-params");
 	dm.add("rockchip-sy-mipi-dphy");
 
-	media_ = enumerator->search(dm);
+	media_ = acquireMediaDevice(enumerator, dm);
 	if (!media_)
 		return false;
 
-	media_->acquire();
-
 	/* Create the V4L2 subdevices we will need. */
-	dphy_ = V4L2Subdevice::fromEntityName(media_.get(),
-					      "rockchip-sy-mipi-dphy");
+	dphy_ = V4L2Subdevice::fromEntityName(media_, "rockchip-sy-mipi-dphy");
 	if (dphy_->open() < 0)
 		return false;
 
-	isp_ = V4L2Subdevice::fromEntityName(media_.get(), "rkisp1-isp-subdev");
+	isp_ = V4L2Subdevice::fromEntityName(media_, "rkisp1-isp-subdev");
 	if (isp_->open() < 0)
 		return false;
 
 	/* Locate and open the capture video node. */
-	video_ = V4L2Device::fromEntityName(media_.get(), "rkisp1_mainpath");
+	video_ = V4L2Device::fromEntityName(media_, "rkisp1_mainpath");
 	if (video_->open() < 0)
 		return false;