libcamera: Refactor the camera configuration storage and API

Refactor the CameraConfiguration structure to not rely on Stream
instances. This is a step towards making the camera configuration object
more powerful with configuration validation using "try" semantics.

The CameraConfiguration now exposes a simple vector-like API to access
the contained stream configurations. Both operator[]() and at() are
provided to access elements. The isEmpty() method is renamed to empty()
and the methods reordered to match the std::vector class.

As applications need access to the Stream instances associated with the
configuration entries in order to associate buffers with streams when
creating requests, expose the stream selected by the pipeline handler
through a new StreamConfiguration::stream().

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

1 files changed, 11 insertions, 12 deletions

diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index 17e2491e..af6b6f21 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -27,8 +27,7 @@ public:
 
 	CameraConfiguration
 	generateConfiguration(Camera *camera, const StreamRoles &roles) override;
-	int configure(Camera *camera,
-		      const CameraConfiguration &config) override;
+	int configure(Camera *camera, CameraConfiguration &config) override;
 
 	int allocateBuffers(Camera *camera,
 			    const std::set<Stream *> &streams) override;
@@ -78,38 +77,38 @@ CameraConfiguration
 PipelineHandlerVimc::generateConfiguration(Camera *camera,
 					   const StreamRoles &roles)
 {
-	VimcCameraData *data = cameraData(camera);
 	CameraConfiguration config;
-	StreamConfiguration cfg{};
+	StreamConfiguration cfg;
 
 	cfg.pixelFormat = V4L2_PIX_FMT_RGB24;
 	cfg.size = { 640, 480 };
 	cfg.bufferCount = 4;
 
-	config[&data->stream_] = cfg;
+	config.addConfiguration(cfg);
 
 	return config;
 }
 
-int PipelineHandlerVimc::configure(Camera *camera,
-				   const CameraConfiguration &config)
+int PipelineHandlerVimc::configure(Camera *camera, CameraConfiguration &config)
 {
 	VimcCameraData *data = cameraData(camera);
-	const StreamConfiguration *cfg = &config[&data->stream_];
+	StreamConfiguration &cfg = config[0];
 	int ret;
 
 	V4L2DeviceFormat format = {};
-	format.fourcc = cfg->pixelFormat;
-	format.size = cfg->size;
+	format.fourcc = cfg.pixelFormat;
+	format.size = cfg.size;
 
 	ret = data->video_->setFormat(&format);
 	if (ret)
 		return ret;
 
-	if (format.size != cfg->size ||
-	    format.fourcc != cfg->pixelFormat)
+	if (format.size != cfg.size ||
+	    format.fourcc != cfg.pixelFormat)
 		return -EINVAL;
 
+	cfg.setStream(&data->stream_);
+
 	return 0;
 }