libcamera: pipeline_handler: Store the camera manager pointer

Instead of passing the camera manager pointer to the match() function,
and later to more PipelineHandler functions, store it in the
PipelineHandler::manager_ member variable at construction time and
access it from there.

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

src/libcamera/camera_manager.cpp

@@ -98,8 +98,8 @@ int CameraManager::start()
 		 * all pipelines it can provide.
 		 */
 		while (1) {
-			PipelineHandler *pipe = factory->create();
-			if (!pipe->match(this, enumerator_.get())) {
+			PipelineHandler *pipe = factory->create(this);
+			if (!pipe->match(enumerator_.get())) {
 				delete pipe;
 				break;
 			}

src/libcamera/include/pipeline_handler.h

@@ -19,9 +19,13 @@ class DeviceEnumerator;
 class PipelineHandler
 {
 public:
-	virtual ~PipelineHandler() { };
+	PipelineHandler(CameraManager *manager);
+	virtual ~PipelineHandler();
 
-	virtual bool match(CameraManager *manager, DeviceEnumerator *enumerator) = 0;
+	virtual bool match(DeviceEnumerator *enumerator) = 0;
+
+protected:
+	CameraManager *manager_;
 };
 
 class PipelineHandlerFactory
@@ -30,7 +34,7 @@ public:
 	PipelineHandlerFactory(const char *name);
 	virtual ~PipelineHandlerFactory() { };
 
-	virtual PipelineHandler *create() = 0;
+	virtual PipelineHandler *create(CameraManager *manager) = 0;
 
 	const std::string &name() const { return name_; }
 
@@ -42,11 +46,13 @@ private:
 };
 
 #define REGISTER_PIPELINE_HANDLER(handler)				\
-class handler##Factory : public PipelineHandlerFactory {		\
+class handler##Factory : public PipelineHandlerFactory			\
+{									\
 public:									\
-	handler##Factory() : PipelineHandlerFactory(#handler) { }	\
-	PipelineHandler *create() final {				\
-		return new handler();					\
+	handler##Factory() : PipelineHandlerFactory(#handler) {}	\
+	PipelineHandler *create(CameraManager *manager) final		\
+	{								\
+		return new handler(manager);				\
 	}								\
 };									\
 static handler##Factory global_##handler##Factory;

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -23,20 +23,20 @@ LOG_DEFINE_CATEGORY(IPU3)
 class PipelineHandlerIPU3 : public PipelineHandler
 {
 public:
-	PipelineHandlerIPU3();
+	PipelineHandlerIPU3(CameraManager *manager);
 	~PipelineHandlerIPU3();
 
-	bool match(CameraManager *manager, DeviceEnumerator *enumerator);
+	bool match(DeviceEnumerator *enumerator);
 
 private:
 	MediaDevice *cio2_;
 	MediaDevice *imgu_;
 
-	void registerCameras(CameraManager *manager);
+	void registerCameras();
 };
 
-PipelineHandlerIPU3::PipelineHandlerIPU3()
-	: cio2_(nullptr), imgu_(nullptr)
+PipelineHandlerIPU3::PipelineHandlerIPU3(CameraManager *manager)
+	: PipelineHandler(manager), cio2_(nullptr), imgu_(nullptr)
 {
 }
 
@@ -52,7 +52,7 @@ PipelineHandlerIPU3::~PipelineHandlerIPU3()
 	imgu_ = nullptr;
 }
 
-bool PipelineHandlerIPU3::match(CameraManager *manager, DeviceEnumerator *enumerator)
+bool PipelineHandlerIPU3::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch cio2_dm("ipu3-cio2");
 	cio2_dm.add("ipu3-csi2 0");
@@ -106,7 +106,7 @@ bool PipelineHandlerIPU3::match(CameraManager *manager, DeviceEnumerator *enumer
 	if (cio2_->disableLinks())
 		goto error_close_cio2;
 
-	registerCameras(manager);
+	registerCameras();
 
 	cio2_->close();
 
@@ -127,7 +127,7 @@ error_release_mdev:
  * media entity with function MEDIA_ENT_F_CAM_SENSOR) to one of the four
  * CIO2 CSI-2 receivers.
  */
-void PipelineHandlerIPU3::registerCameras(CameraManager *manager)
+void PipelineHandlerIPU3::registerCameras()
 {
 	/*
 	 * For each CSI-2 receiver on the IPU3, create a Camera if an
@@ -172,7 +172,7 @@ void PipelineHandlerIPU3::registerCameras(CameraManager *manager)
 
 		std::string cameraName = sensor->name() + " " + std::to_string(id);
 		std::shared_ptr<Camera> camera = Camera::create(cameraName);
-		manager->addCamera(std::move(camera));
+		manager_->addCamera(std::move(camera));
 
 		LOG(IPU3, Info)
 			<< "Registered Camera[" << numCameras << "] \""

src/libcamera/pipeline/uvcvideo.cpp

@@ -17,17 +17,17 @@ namespace libcamera {
 class PipelineHandlerUVC : public PipelineHandler
 {
 public:
-	PipelineHandlerUVC();
+	PipelineHandlerUVC(CameraManager *manager);
 	~PipelineHandlerUVC();
 
-	bool match(CameraManager *manager, DeviceEnumerator *enumerator);
+	bool match(DeviceEnumerator *enumerator);
 
 private:
 	MediaDevice *dev_;
 };
 
-PipelineHandlerUVC::PipelineHandlerUVC()
-	: dev_(nullptr)
+PipelineHandlerUVC::PipelineHandlerUVC(CameraManager *manager)
+	: PipelineHandler(manager), dev_(nullptr)
 {
 }
 
@@ -37,7 +37,7 @@ PipelineHandlerUVC::~PipelineHandlerUVC()
 		dev_->release();
 }
 
-bool PipelineHandlerUVC::match(CameraManager *manager, DeviceEnumerator *enumerator)
+bool PipelineHandlerUVC::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch dm("uvcvideo");
 
@@ -49,7 +49,7 @@ bool PipelineHandlerUVC::match(CameraManager *manager, DeviceEnumerator *enumera
 	dev_->acquire();
 
 	std::shared_ptr<Camera> camera = Camera::create(dev_->model());
-	manager->addCamera(std::move(camera));
+	manager_->addCamera(std::move(camera));
 
 	return true;
 }

src/libcamera/pipeline/vimc.cpp

@@ -17,17 +17,17 @@ namespace libcamera {
 class PipeHandlerVimc : public PipelineHandler
 {
 public:
-	PipeHandlerVimc();
+	PipeHandlerVimc(CameraManager *manager);
 	~PipeHandlerVimc();
 
-	bool match(CameraManager *manager, DeviceEnumerator *enumerator);
+	bool match(DeviceEnumerator *enumerator);
 
 private:
 	MediaDevice *dev_;
 };
 
-PipeHandlerVimc::PipeHandlerVimc()
-	: dev_(nullptr)
+PipeHandlerVimc::PipeHandlerVimc(CameraManager *manager)
+	: PipelineHandler(manager), dev_(nullptr)
 {
 }
 
@@ -37,7 +37,7 @@ PipeHandlerVimc::~PipeHandlerVimc()
 		dev_->release();
 }
 
-bool PipeHandlerVimc::match(CameraManager *manager, DeviceEnumerator *enumerator)
+bool PipeHandlerVimc::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch dm("vimc");
 
@@ -65,7 +65,7 @@ bool PipeHandlerVimc::match(CameraManager *manager, DeviceEnumerator *enumerator
 	 * object is modeled.
 	 */
 	std::shared_ptr<Camera> camera = Camera::create("Dummy VIMC Camera");
-	manager->addCamera(std::move(camera));
+	manager_->addCamera(std::move(camera));
 
 	return true;
 }

src/libcamera/pipeline_handler.cpp

@@ -34,18 +34,30 @@ LOG_DEFINE_CATEGORY(Pipeline)
  * with the pipelines it supports and creates corresponding Camera devices.
  */
 
+/**
+ * \brief Construct a PipelineHandler instance
+ * \param[in] manager The camera manager
+ */
+PipelineHandler::PipelineHandler(CameraManager *manager)
+	: manager_(manager)
+{
+}
+
+PipelineHandler::~PipelineHandler()
+{
+}
+
 /**
  * \fn PipelineHandler::match(DeviceEnumerator *enumerator)
  * \brief Match media devices and create camera instances
- * \param manager The camera manager
  * \param enumerator The enumerator providing all media devices found in the
  * system
  *
  * This function is the main entry point of the pipeline handler. It is called
- * by the camera manager with the \a manager and \a enumerator passed as
- * arguments. It shall acquire from the \a enumerator all the media devices it
- * needs for a single pipeline, create one or multiple Camera instances and
- * register them with the \a manager.
+ * by the camera manager with the \a enumerator passed as an argument. It shall
+ * acquire from the \a enumerator all the media devices it needs for a single
+ * pipeline, create one or multiple Camera instances and register them with the
+ * camera manager.
  *
  * If all media devices needed by the pipeline handler are found, they must all
  * be acquired by a call to MediaDevice::acquire(). This function shall then
@@ -66,6 +78,15 @@ LOG_DEFINE_CATEGORY(Pipeline)
  * created, or false otherwise
  */
 
+/**
+ * \var PipelineHandler::manager_
+ * \brief The Camera manager associated with the pipeline handler
+ *
+ * The camera manager pointer is stored in the pipeline handler for the
+ * convenience of pipeline handler implementations. It remains valid and
+ * constant for the whole lifetime of the pipeline handler.
+ */
+
 /**
  * \class PipelineHandlerFactory
  * \brief Registration of PipelineHandler classes and creation of instances
@@ -96,8 +117,11 @@ PipelineHandlerFactory::PipelineHandlerFactory(const char *name)
 /**
  * \fn PipelineHandlerFactory::create()
  * \brief Create an instance of the PipelineHandler corresponding to the factory
+ * \param[in] manager The camera manager
  *
- * This virtual function is implemented by the REGISTER_PIPELINE_HANDLER() macro.
+ * This virtual function is implemented by the REGISTER_PIPELINE_HANDLER()
+ * macro. It creates a pipeline handler instance associated with the camera
+ * \a manager.
  *
  * \return a pointer to a newly constructed instance of the PipelineHandler
  * subclass corresponding to the factory