libcamera: camera: Pass the stream set to allocate/freeBuffers()

Pipeline handlers might need to perform allocation of internal buffers,
setup operations, or simple sanity check before going into the
per-stream buffer allocation.

As of now, PipelineHandler::allocateBuffers() is called once for each
active stream, leaving no space for stream-independent configuration.

Change this by providing to the pipeline handlers the full set of active
streams, and ask them to loop over them to perform per-streams
memory allocations and freeing.

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

6 files changed, 43 insertions, 28 deletions

diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index bdf14b31..21caa24b 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -647,13 +647,11 @@ int Camera::allocateBuffers()
 		return -EINVAL;
 	}
 
-	for (Stream *stream : activeStreams_) {
-		int ret = pipe_->allocateBuffers(this, stream);
-		if (ret) {
-			LOG(Camera, Error) << "Failed to allocate buffers";
-			freeBuffers();
-			return ret;
-		}
+	int ret = pipe_->allocateBuffers(this, activeStreams_);
+	if (ret) {
+		LOG(Camera, Error) << "Failed to allocate buffers";
+		freeBuffers();
+		return ret;
 	}
 
 	state_ = CameraPrepared;
@@ -683,12 +681,11 @@ int Camera::freeBuffers()
 		 * by the V4L2 device that has allocated them.
 		 */
 		stream->bufferPool().destroyBuffers();
-		pipe_->freeBuffers(this, stream);
 	}
 
 	state_ = CameraConfigured;
 
-	return 0;
+	return pipe_->freeBuffers(this, activeStreams_);
 }
 
 /**
diff --git a/src/libcamera/include/pipeline_handler.h b/src/libcamera/include/pipeline_handler.h
index 33b820e7..a0862ebf 100644
--- a/src/libcamera/include/pipeline_handler.h
+++ b/src/libcamera/include/pipeline_handler.h
@@ -58,8 +58,10 @@ public:
 	streamConfiguration(Camera *camera, const std::vector<StreamUsage> &usages) = 0;
 	virtual int configureStreams(Camera *camera, const CameraConfiguration &config) = 0;
 
-	virtual int allocateBuffers(Camera *camera, Stream *stream) = 0;
-	virtual int freeBuffers(Camera *camera, Stream *stream) = 0;
+	virtual int allocateBuffers(Camera *camera,
+				    const std::set<Stream *> &streams) = 0;
+	virtual int freeBuffers(Camera *camera,
+				const std::set<Stream *> &streams) = 0;
 
 	virtual int start(Camera *camera) = 0;
 	virtual void stop(Camera *camera);
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index ca09da75..f96e8763 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -145,8 +145,10 @@ public:
 	int configureStreams(Camera *camera,
 			     const CameraConfiguration &config) override;
 
-	int allocateBuffers(Camera *camera, Stream *stream) override;
-	int freeBuffers(Camera *camera, Stream *stream) override;
+	int allocateBuffers(Camera *camera,
+			    const std::set<Stream *> &streams) override;
+	int freeBuffers(Camera *camera,
+			const std::set<Stream *> &streams) override;
 
 	int start(Camera *camera) override;
 	void stop(Camera *camera) override;
@@ -305,9 +307,11 @@ int PipelineHandlerIPU3::configureStreams(Camera *camera,
 	return 0;
 }
 
-int PipelineHandlerIPU3::allocateBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerIPU3::allocateBuffers(Camera *camera,
+					 const std::set<Stream *> &streams)
 {
 	IPU3CameraData *data = cameraData(camera);
+	Stream *stream = *streams.begin();
 	CIO2Device *cio2 = &data->cio2_;
 	ImgUDevice *imgu = data->imgu_;
 	int ret;
@@ -346,7 +350,8 @@ int PipelineHandlerIPU3::allocateBuffers(Camera *camera, Stream *stream)
 	return 0;
 }
 
-int PipelineHandlerIPU3::freeBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerIPU3::freeBuffers(Camera *camera,
+				     const std::set<Stream *> &streams)
 {
 	IPU3CameraData *data = cameraData(camera);
 
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index cd472cfa..b8f634d8 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.cpp
@@ -32,8 +32,10 @@ public:
 	int configureStreams(Camera *camera,
 			     const CameraConfiguration &config) override;
 
-	int allocateBuffers(Camera *camera, Stream *stream) override;
-	int freeBuffers(Camera *camera, Stream *stream) override;
+	int allocateBuffers(Camera *camera,
+			    const std::set<Stream *> &streams) override;
+	int freeBuffers(Camera *camera,
+			const std::set<Stream *> &streams) override;
 
 	int start(Camera *camera) override;
 	void stop(Camera *camera) override;
@@ -127,9 +129,11 @@ int PipelineHandlerUVC::configureStreams(Camera *camera,
 	return 0;
 }
 
-int PipelineHandlerUVC::allocateBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerUVC::allocateBuffers(Camera *camera,
+					const std::set<Stream *> &streams)
 {
 	UVCCameraData *data = cameraData(camera);
+	Stream *stream = *streams.begin();
 	const StreamConfiguration &cfg = stream->configuration();
 
 	LOG(UVC, Debug) << "Requesting " << cfg.bufferCount << " buffers";
@@ -137,7 +141,8 @@ int PipelineHandlerUVC::allocateBuffers(Camera *camera, Stream *stream)
 	return data->video_->exportBuffers(&stream->bufferPool());
 }
 
-int PipelineHandlerUVC::freeBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerUVC::freeBuffers(Camera *camera,
+				    const std::set<Stream *> &streams)
 {
 	UVCCameraData *data = cameraData(camera);
 	return data->video_->releaseBuffers();
diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index c8bbe2a1..22449e47 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -32,8 +32,10 @@ public:
 	int configureStreams(Camera *camera,
 			     const CameraConfiguration &config) override;
 
-	int allocateBuffers(Camera *camera, Stream *stream) override;
-	int freeBuffers(Camera *camera, Stream *stream) override;
+	int allocateBuffers(Camera *camera,
+			    const std::set<Stream *> &streams) override;
+	int freeBuffers(Camera *camera,
+			const std::set<Stream *> &streams) override;
 
 	int start(Camera *camera) override;
 	void stop(Camera *camera) override;
@@ -127,9 +129,11 @@ int PipelineHandlerVimc::configureStreams(Camera *camera,
 	return 0;
 }
 
-int PipelineHandlerVimc::allocateBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerVimc::allocateBuffers(Camera *camera,
+					 const std::set<Stream *> &streams)
 {
 	VimcCameraData *data = cameraData(camera);
+	Stream *stream = *streams.begin();
 	const StreamConfiguration &cfg = stream->configuration();
 
 	LOG(VIMC, Debug) << "Requesting " << cfg.bufferCount << " buffers";
@@ -137,7 +141,8 @@ int PipelineHandlerVimc::allocateBuffers(Camera *camera, Stream *stream)
 	return data->video_->exportBuffers(&stream->bufferPool());
 }
 
-int PipelineHandlerVimc::freeBuffers(Camera *camera, Stream *stream)
+int PipelineHandlerVimc::freeBuffers(Camera *camera,
+				     const std::set<Stream *> &streams)
 {
 	VimcCameraData *data = cameraData(camera);
 	return data->video_->releaseBuffers();
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 43550c0e..911d0844 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -193,10 +193,11 @@ PipelineHandler::~PipelineHandler()
  * \fn PipelineHandler::allocateBuffers()
  * \brief Allocate buffers for a stream
  * \param[in] camera The camera the \a stream belongs to
- * \param[in] stream The stream to allocate buffers for
+ * \param[in] streams The set of streams to allocate buffers for
  *
- * This method allocates buffers internally in the pipeline handler and
- * associates them with the stream's buffer pool.
+ * This method allocates buffers internally in the pipeline handler for each
+ * stream in the \a streams buffer set, and associates them with the stream's
+ * buffer pool.
  *
  * The intended caller of this method is the Camera class.
  *
@@ -207,9 +208,9 @@ PipelineHandler::~PipelineHandler()
  * \fn PipelineHandler::freeBuffers()
  * \brief Free all buffers associated with a stream
  * \param[in] camera The camera the \a stream belongs to
- * \param[in] stream The stream to free buffers from
+ * \param[in] streams The set of streams to free buffers from
  *
- * After a capture session has been stopped all buffers associated with the
+ * After a capture session has been stopped all buffers associated with each
  * stream shall be freed.
  *
  * The intended caller of this method is the Camera class.