3 files changed, 40 insertions, 6 deletions

diff --git a/include/libcamera/camera_manager.h b/include/libcamera/camera_manager.h
index 95dc6360..9eb2b6f5 100644
--- a/include/libcamera/camera_manager.h
+++ b/include/libcamera/camera_manager.h
@@ -13,6 +13,7 @@
 #include <vector>
 
 #include <libcamera/object.h>
+#include <libcamera/signal.h>
 
 namespace libcamera {
 
@@ -36,13 +37,16 @@ public:
 
 	void addCamera(std::shared_ptr<Camera> camera,
 		       const std::vector<dev_t> &devnums);
-	void removeCamera(Camera *camera);
+	void removeCamera(std::shared_ptr<Camera> camera);
 
 	static const std::string &version() { return version_; }
 
 	void setEventDispatcher(std::unique_ptr<EventDispatcher> dispatcher);
 	EventDispatcher *eventDispatcher();
 
+	Signal<std::shared_ptr<Camera>> cameraAdded;
+	Signal<std::shared_ptr<Camera>> cameraRemoved;
+
 private:
 	static const std::string version_;
 	static CameraManager *self_;
diff --git a/src/libcamera/camera_manager.cpp b/src/libcamera/camera_manager.cpp
index 30827976..f60491d2 100644
--- a/src/libcamera/camera_manager.cpp
+++ b/src/libcamera/camera_manager.cpp
@@ -36,7 +36,7 @@ public:
 	Private(CameraManager *cm);
 
 	int start();
-	void addCamera(std::shared_ptr<Camera> &camera,
+	void addCamera(std::shared_ptr<Camera> camera,
 		       const std::vector<dev_t> &devnums);
 	void removeCamera(Camera *camera);
 
@@ -171,7 +171,7 @@ void CameraManager::Private::cleanup()
 	enumerator_.reset(nullptr);
 }
 
-void CameraManager::Private::addCamera(std::shared_ptr<Camera> &camera,
+void CameraManager::Private::addCamera(std::shared_ptr<Camera> camera,
 				       const std::vector<dev_t> &devnums)
 {
 	MutexLocker locker(mutex_);
@@ -375,6 +375,34 @@ std::shared_ptr<Camera> CameraManager::get(dev_t devnum)
 }
 
 /**
+ * \var CameraManager::cameraAdded
+ * \brief Notify of a new camera added to the system
+ *
+ * This signal is emitted when a new camera is detected and successfully handled
+ * by the camera manager. The notification occurs alike for cameras detected
+ * when the manager is started with start() or when new cameras are later
+ * connected to the system. When the signal is emitted the new camera is already
+ * available from the list of cameras().
+ *
+ * The signal is emitted from the CameraManager thread. Applications shall
+ * minimize the time spent in the signal handler and shall in particular not
+ * perform any blocking operation.
+ */
+
+/**
+ * \var CameraManager::cameraRemoved
+ * \brief Notify of a new camera removed from the system
+ *
+ * This signal is emitted when a camera is removed from the system. When the
+ * signal is emitted the camera is not available from the list of cameras()
+ * anymore.
+ *
+ * The signal is emitted from the CameraManager thread. Applications shall
+ * minimize the time spent in the signal handler and shall in particular not
+ * perform any blocking operation.
+ */
+
+/**
  * \brief Add a camera to the camera manager
  * \param[in] camera The camera to be added
  * \param[in] devnums The device numbers to associate with \a camera
@@ -394,6 +422,7 @@ void CameraManager::addCamera(std::shared_ptr<Camera> camera,
 	ASSERT(Thread::current() == p_.get());
 
 	p_->addCamera(camera, devnums);
+	cameraAdded.emit(camera);
 }
 
 /**
@@ -406,11 +435,12 @@ void CameraManager::addCamera(std::shared_ptr<Camera> camera,
  *
  * \context This function shall be called from the CameraManager thread.
  */
-void CameraManager::removeCamera(Camera *camera)
+void CameraManager::removeCamera(std::shared_ptr<Camera> camera)
 {
 	ASSERT(Thread::current() == p_.get());
 
-	p_->removeCamera(camera);
+	p_->removeCamera(camera.get());
+	cameraRemoved.emit(camera);
 }
 
 /**
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 38c85779..14dfba0b 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -579,7 +579,7 @@ void PipelineHandler::disconnect()
 			continue;
 
 		camera->disconnect();
-		manager_->removeCamera(camera.get());
+		manager_->removeCamera(camera);
 	}
 }