8 files changed, 25 insertions, 41 deletions
diff --git a/src/cam/main.cpp b/src/cam/main.cpp
index b5895fae..d45ffd37 100644
--- a/src/cam/main.cpp
+++ b/src/cam/main.cpp
@@ -80,8 +80,7 @@ static int parseOptions(int argc, char *argv[])
 
 static int prepareCameraConfig(std::map<Stream *, StreamConfiguration> *config)
 {
-	std::set<Stream *> streams = camera->streams();
-	*config = camera->streamConfiguration(streams);
+	*config = camera->streamConfiguration({ Stream::VideoRecording() });
 	Stream *stream = config->begin()->first;
 
 	if (options.isSet(OptFormat)) {
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index 8ee9cc08..63fde0ff 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -345,33 +345,23 @@ const std::set<Stream *> &Camera::streams() const
 }
 
 /**
- * \brief Retrieve a group of stream configurations
- * \param[in] streams A map of stream IDs and configurations to setup
+ * \brief Retrieve a group of stream configurations according to stream usages
+ * \param[in] usages A list of stream usages
  *
- * Retrieve the camera's configuration for a specified group of streams. The
- * caller can specifies which of the camera's streams to retrieve configuration
- * from by populating \a streams.
+ * Retrieve configuration for a set of desired usages. The caller specifies a
+ * list of stream usages and the camera returns a map of suitable streams and
+ * their suggested default configurations.
  *
- * The easiest way to populate the array of streams to fetch configuration from
- * is to first retrieve the camera's full array of stream with streams() and
- * then potentially trim it down to only contain the streams the caller
- * are interested in.
- *
- * \return A map of successfully retrieved stream IDs and configurations or an
- * empty list on error.
+ * \return A map of streams to configurations if the requested usages can be
+ * satisfied, or an empty map otherwise
  */
 std::map<Stream *, StreamConfiguration>
-Camera::streamConfiguration(std::set<Stream *> &streams)
+Camera::streamConfiguration(const std::vector<StreamUsage> &usages)
 {
-	if (disconnected_ || !streams.size())
+	if (disconnected_ || !usages.size() || usages.size() > streams_.size())
 		return std::map<Stream *, StreamConfiguration>{};
 
-	for (Stream *stream : streams) {
-		if (streams_.find(stream) == streams_.end())
-			return std::map<Stream *, StreamConfiguration>{};
-	}
-
-	return pipe_->streamConfiguration(this, streams);
+	return pipe_->streamConfiguration(this, usages);
 }
 
 /**
diff --git a/src/libcamera/include/pipeline_handler.h b/src/libcamera/include/pipeline_handler.h
index acb376e0..8a1706fa 100644
--- a/src/libcamera/include/pipeline_handler.h
+++ b/src/libcamera/include/pipeline_handler.h
@@ -53,7 +53,7 @@ public:
 	virtual bool match(DeviceEnumerator *enumerator) = 0;
 
 	virtual std::map<Stream *, StreamConfiguration>
-	streamConfiguration(Camera *camera, std::set<Stream *> &streams) = 0;
+	streamConfiguration(Camera *camera, const std::vector<StreamUsage> &usages) = 0;
 	virtual int configureStreams(Camera *camera,
 				     std::map<Stream *, StreamConfiguration> &config) = 0;
 
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index fed04ce5..5d01504e 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -141,7 +141,7 @@ public:
 
 	std::map<Stream *, StreamConfiguration>
 	streamConfiguration(Camera *camera,
-			    std::set<Stream *> &streams) override;
+			    const std::vector<StreamUsage> &usages) override;
 	int configureStreams(Camera *camera,
 			     std::map<Stream *, StreamConfiguration> &config) override;
 
@@ -206,7 +206,7 @@ PipelineHandlerIPU3::~PipelineHandlerIPU3()
 
 std::map<Stream *, StreamConfiguration>
 PipelineHandlerIPU3::streamConfiguration(Camera *camera,
-					 std::set<Stream *> &streams)
+					 const std::vector<StreamUsage> &usages)
 {
 	std::map<Stream *, StreamConfiguration> configs;
 	IPU3CameraData *data = cameraData(camera);
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index cc3e0cd9..dfff7116 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.cpp
@@ -28,7 +28,7 @@ public:
 
 	std::map<Stream *, StreamConfiguration>
 	streamConfiguration(Camera *camera,
-			    std::set<Stream *> &streams) override;
+			    const std::vector<StreamUsage> &usages) override;
 	int configureStreams(Camera *camera,
 			     std::map<Stream *, StreamConfiguration> &config) override;
 
@@ -84,14 +84,12 @@ PipelineHandlerUVC::~PipelineHandlerUVC()
 
 std::map<Stream *, StreamConfiguration>
 PipelineHandlerUVC::streamConfiguration(Camera *camera,
-					std::set<Stream *> &streams)
+					const std::vector<StreamUsage> &usages)
 {
 	UVCCameraData *data = cameraData(camera);
-
 	std::map<Stream *, StreamConfiguration> configs;
 	StreamConfiguration config{};
 
-	LOG(UVC, Debug) << "Retrieving default format";
 	config.width = 640;
 	config.height = 480;
 	config.pixelFormat = V4L2_PIX_FMT_YUYV;
diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index 2e8c26fb..4da4ca01 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -28,7 +28,7 @@ public:
 
 	std::map<Stream *, StreamConfiguration>
 	streamConfiguration(Camera *camera,
-			    std::set<Stream *> &streams) override;
+			    const std::vector<StreamUsage> &usages) override;
 	int configureStreams(Camera *camera,
 			     std::map<Stream *, StreamConfiguration> &config) override;
 
@@ -84,14 +84,12 @@ PipelineHandlerVimc::~PipelineHandlerVimc()
 
 std::map<Stream *, StreamConfiguration>
 PipelineHandlerVimc::streamConfiguration(Camera *camera,
-					 std::set<Stream *> &streams)
+					 const std::vector<StreamUsage> &usages)
 {
 	VimcCameraData *data = cameraData(camera);
 	std::map<Stream *, StreamConfiguration> configs;
-
 	StreamConfiguration config{};
 
-	LOG(VIMC, Debug) << "Retrieving default format";
 	config.width = 640;
 	config.height = 480;
 	config.pixelFormat = V4L2_PIX_FMT_RGB24;
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 1a858f26..0574f990 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -152,13 +152,13 @@ PipelineHandler::~PipelineHandler()
  * \fn PipelineHandler::streamConfiguration()
  * \brief Retrieve a group of stream configurations for a specified camera
  * \param[in] camera The camera to fetch default configuration from
- * \param[in] streams An array of streams to fetch information about
+ * \param[in] usages A list of stream usages
  *
  * Retrieve the species camera's default configuration for a specified group of
- * streams. The caller shall populate the \a streams array with the streams it
- * wish to fetch the configuration from. The map of streams and configuration
- * returned can then be examined by the caller to learn about the defualt
- * parameters for the specified streams.
+ * use-cases. The caller shall populate the \a usages array with the use-cases it
+ * wishes to fetch the default configuration for. The map of streams and
+ * configurations returned can then be examined by the caller to learn about
+ * the default parameters for the specified streams.
  *
  * The intended companion to this is \a configureStreams() which can be used to
  * change the group of streams parameters.
diff --git a/src/qcam/main_window.cpp b/src/qcam/main_window.cpp
index fea70142..faa3bc57 100644
--- a/src/qcam/main_window.cpp
+++ b/src/qcam/main_window.cpp
@@ -97,9 +97,8 @@ int MainWindow::startCapture()
 {
 	int ret;
 
-	Stream *stream = *camera_->streams().begin();
-	std::set<Stream *> streams{ stream };
-	config_ = camera_->streamConfiguration(streams);
+	config_ = camera_->streamConfiguration({ Stream::VideoRecording() });
+	Stream *stream = config_.begin()->first;
 	ret = camera_->configureStreams(config_);
 	if (ret < 0) {
 		std::cout << "Failed to configure camera" << std::endl;