[libcamera-devel] [PATCH 2/3] libcamera: pipelines: keep reference to cameras created

[Niklas Söderlund]

The pipeline handlers needs to keep a reference to the cameras it
creates in order to notify it when it's being disconnected. When
hot-unplug support is added the pipeline handler would be deleted when
the hardware is removed from under it.

After the deletion of pipeline handler all the Camera objects created by
the pipeline handler might still be around as they might be in use by a
application. At this point the pipeline handler should inform the camera
that it's disconnected.

Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
---
 src/libcamera/pipeline/ipu3/ipu3.cpp |  7 ++++++-
 src/libcamera/pipeline/uvcvideo.cpp  | 10 +++++++---
 src/libcamera/pipeline/vimc.cpp      | 11 +++++++----
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 48d028f7e6cd9b4d..19f73011f8b75438 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -32,6 +32,8 @@ private:
 	MediaDevice *cio2_;
 	MediaDevice *imgu_;
 
+	std::vector<std::shared_ptr<Camera>> cameras_;
+
 	void registerCameras(CameraManager *manager);
 };
 
@@ -42,6 +44,8 @@ PipelineHandlerIPU3::PipelineHandlerIPU3()
 
 PipelineHandlerIPU3::~PipelineHandlerIPU3()
 {
+	cameras_.clear();
+
 	if (cio2_)
 		cio2_->release();
 
@@ -173,7 +177,8 @@ void PipelineHandlerIPU3::registerCameras(CameraManager *manager)
 		std::string cameraName = sensor->name() + " " + std::to_string(id);
 		std::shared_ptr<Camera> camera = Camera::create(cameraName,
 								this);
-		manager->addCamera(std::move(camera));
+		cameras_.push_back(camera);
+		manager->addCamera(camera);
 
 		LOG(IPU3, Info)
 			<< "Registered Camera[" << numCameras << "] \""
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index 3651250b683e7810..2162824eb571fba7 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.cpp
@@ -24,15 +24,19 @@ public:
 
 private:
 	MediaDevice *dev_;
+	std::shared_ptr<Camera> camera_;
 };
 
 PipelineHandlerUVC::PipelineHandlerUVC()
-	: dev_(nullptr)
+	: dev_(nullptr), camera_(nullptr)
 {
 }
 
 PipelineHandlerUVC::~PipelineHandlerUVC()
 {
+	if (camera_)
+		camera_ = nullptr;
+
 	if (dev_)
 		dev_->release();
 }
@@ -48,8 +52,8 @@ bool PipelineHandlerUVC::match(CameraManager *manager, DeviceEnumerator *enumera
 
 	dev_->acquire();
 
-	std::shared_ptr<Camera> camera = Camera::create(dev_->model(), this);
-	manager->addCamera(std::move(camera));
+	camera_ = Camera::create(dev_->model(), this);
+	manager->addCamera(camera_);
 
 	return true;
 }
diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index 81d8319eb88e06d2..373fc0ee5339f9ae 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -24,15 +24,19 @@ public:
 
 private:
 	MediaDevice *dev_;
+	std::shared_ptr<Camera> camera_;
 };
 
 PipeHandlerVimc::PipeHandlerVimc()
-	: dev_(nullptr)
+	: dev_(nullptr), camera_(nullptr)
 {
 }
 
 PipeHandlerVimc::~PipeHandlerVimc()
 {
+	if (camera_)
+		camera_ = nullptr;
+
 	if (dev_)
 		dev_->release();
 }
@@ -57,9 +61,8 @@ bool PipeHandlerVimc::match(CameraManager *manager, DeviceEnumerator *enumerator
 
 	dev_->acquire();
 
-	std::shared_ptr<Camera> camera = Camera::create("Dummy VIMC Camera",
-							this);
-	manager->addCamera(std::move(camera));
+	camera_ = Camera::create("Dummy VIMC Camera", this);
+	manager->addCamera(camera_);
 
 	return true;
 }
-- 
2.20.1