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>

4 files changed, 44 insertions, 46 deletions

diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index d234a8ac..ed0ef69d 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -152,8 +152,7 @@ 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;
@@ -299,14 +298,13 @@ PipelineHandlerIPU3::generateConfiguration(Camera *camera,
 		cfg.pixelFormat = V4L2_PIX_FMT_NV12;
 		cfg.bufferCount = IPU3_BUFFER_COUNT;
 
-		config[stream] = cfg;
+		config.addConfiguration(cfg);
 	}
 
 	return config;
 }
 
-int PipelineHandlerIPU3::configure(Camera *camera,
-				   const CameraConfiguration &config)
+int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration &config)
 {
 	IPU3CameraData *data = cameraData(camera);
 	IPU3Stream *outStream = &data->outStream_;
@@ -318,9 +316,13 @@ int PipelineHandlerIPU3::configure(Camera *camera,
 
 	outStream->active_ = false;
 	vfStream->active_ = false;
-	for (Stream *s : config) {
-		IPU3Stream *stream = static_cast<IPU3Stream *>(s);
-		const StreamConfiguration &cfg = config[stream];
+	for (StreamConfiguration &cfg : config) {
+		/*
+		 * Pick a stream for the configuration entry.
+		 * \todo: This is a naive temporary implementation that will be
+		 * reworked when implementing camera configuration validation.
+		 */
+		IPU3Stream *stream = vfStream->active_ ? outStream : vfStream;
 
 		/*
 		 * Verify that the requested size respects the IPU3 alignment
@@ -355,6 +357,7 @@ int PipelineHandlerIPU3::configure(Camera *camera,
 			sensorSize.height = cfg.size.height;
 
 		stream->active_ = true;
+		cfg.setStream(stream);
 	}
 
 	/*
@@ -379,10 +382,9 @@ int PipelineHandlerIPU3::configure(Camera *camera,
 		return ret;
 
 	/* Apply the format to the configured streams output devices. */
-	for (Stream *s : config) {
-		IPU3Stream *stream = static_cast<IPU3Stream *>(s);
-
-		ret = imgu->configureOutput(stream->device_, config[stream]);
+	for (StreamConfiguration &cfg : config) {
+		IPU3Stream *stream = static_cast<IPU3Stream *>(cfg.stream());
+		ret = imgu->configureOutput(stream->device_, cfg);
 		if (ret)
 			return ret;
 	}
@@ -393,15 +395,13 @@ int PipelineHandlerIPU3::configure(Camera *camera,
 	 * be at least one active stream in the configuration request).
 	 */
 	if (!outStream->active_) {
-		ret = imgu->configureOutput(outStream->device_,
-					    config[vfStream]);
+		ret = imgu->configureOutput(outStream->device_, config[0]);
 		if (ret)
 			return ret;
 	}
 
 	if (!vfStream->active_) {
-		ret = imgu->configureOutput(vfStream->device_,
-					    config[outStream]);
+		ret = imgu->configureOutput(vfStream->device_, config[0]);
 		if (ret)
 			return ret;
 	}
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index 4bd8c510..ec6980b0 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -36,8 +36,7 @@ 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;
@@ -117,16 +116,15 @@ CameraConfiguration PipelineHandlerRkISP1::generateConfiguration(Camera *camera,
 	cfg.size = data->sensor_->resolution();
 	cfg.bufferCount = RKISP1_BUFFER_COUNT;
 
-	config[&data->stream_] = cfg;
+	config.addConfiguration(cfg);
 
 	return config;
 }
 
-int PipelineHandlerRkISP1::configure(Camera *camera,
-				     const CameraConfiguration &config)
+int PipelineHandlerRkISP1::configure(Camera *camera, CameraConfiguration &config)
 {
 	RkISP1CameraData *data = cameraData(camera);
-	const StreamConfiguration &cfg = config[&data->stream_];
+	StreamConfiguration &cfg = config[0];
 	CameraSensor *sensor = data->sensor_;
 	int ret;
 
@@ -217,6 +215,8 @@ int PipelineHandlerRkISP1::configure(Camera *camera,
 		return -EINVAL;
 	}
 
+	cfg.setStream(&data->stream_);
+
 	return 0;
 }
 
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index d2e1f7d4..5dcc868b 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.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
 PipelineHandlerUVC::generateConfiguration(Camera *camera,
 					  const StreamRoles &roles)
 {
-	UVCCameraData *data = cameraData(camera);
 	CameraConfiguration config;
-	StreamConfiguration cfg{};
+	StreamConfiguration cfg;
 
 	cfg.pixelFormat = V4L2_PIX_FMT_YUYV;
 	cfg.size = { 640, 480 };
 	cfg.bufferCount = 4;
 
-	config[&data->stream_] = cfg;
+	config.addConfiguration(cfg);
 
 	return config;
 }
 
-int PipelineHandlerUVC::configure(Camera *camera,
-				  const CameraConfiguration &config)
+int PipelineHandlerUVC::configure(Camera *camera, CameraConfiguration &config)
 {
 	UVCCameraData *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;
 }
 
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;
 }