[libcamera-devel] [RFC 10/11] libcamera: pipeline_handler: Add functions to lock a whole pipeline

[Niklas Söderlund]

Add lock() and unlock() which backed by the MediaDevice implementation
can will lock all media devices claimed by a pipeline handler instance.

Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
---
 src/libcamera/include/pipeline_handler.h |  3 +++
 src/libcamera/pipeline_handler.cpp       | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/libcamera/include/pipeline_handler.h b/src/libcamera/include/pipeline_handler.h
index d995a7e56d90f706..0e79b05035cc2abb 100644
--- a/src/libcamera/include/pipeline_handler.h
+++ b/src/libcamera/include/pipeline_handler.h
@@ -56,6 +56,9 @@ public:
 	std::shared_ptr<MediaDevice> tryAcquire(DeviceEnumerator *enumerator,
 						const DeviceMatch &dm);
 
+	bool lock();
+	void unlock();
+
 	virtual CameraConfiguration
 	streamConfiguration(Camera *camera, const std::vector<StreamUsage> &usages) = 0;
 	virtual int configureStreams(Camera *camera, const CameraConfiguration &config) = 0;
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 7f4035c008f95f91..317b680214d91071 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -170,6 +170,24 @@ out:
 	return media;
 }
 
+bool PipelineHandler::lock()
+{
+	for (std::shared_ptr<MediaDevice> media : mediaDevices_) {
+		if (!media->lock()) {
+			unlock();
+			return false;
+		}
+	}
+
+	return true;
+}
+
+void PipelineHandler::unlock()
+{
+	for (std::shared_ptr<MediaDevice> media : mediaDevices_)
+		media->unlock();
+}
+
 /**
  * \fn PipelineHandler::streamConfiguration()
  * \brief Retrieve a group of stream configurations for a specified camera
-- 
2.21.0