pipeline: ipa: raspberrypi: Refactor and move the Raspberry Pi code

Split the Raspberry Pi pipeline handler and IPA source code into common
and VC4/BCM2835 specific file structures.

For the pipeline handler, the common code files now live in
src/libcamera/pipeline/rpi/common/
and the VC4-specific files in src/libcamera/pipeline/rpi/vc4/.

For the IPA, the common code files now live in
src/ipa/rpi/{cam_helper,controller}/
and the vc4 specific files in src/ipa/rpi/vc4/. With this change, the
camera tuning files are now installed under share/libcamera/ipa/rpi/vc4/.

To build the pipeline and IPA, the meson configuration options have now
changed from "raspberrypi" to "rpi/vc4":

meson setup build -Dipas=rpi/vc4 -Dpipelines=rpi/vc4

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/ipa/rpi/controller/algorithm.h

@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2019, Raspberry Pi Ltd
+ *
+ * algorithm.h - ISP control algorithm interface
+ */
+#pragma once
+
+/*
+ * All algorithms should be derived from this class and made available to the
+ * Controller.
+ */
+
+#include <string>
+#include <memory>
+#include <map>
+
+#include "libcamera/internal/yaml_parser.h"
+
+#include "controller.h"
+
+namespace RPiController {
+
+/* This defines the basic interface for all control algorithms. */
+
+class Algorithm
+{
+public:
+	Algorithm(Controller *controller)
+		: controller_(controller)
+	{
+	}
+	virtual ~Algorithm() = default;
+	virtual char const *name() const = 0;
+	virtual int read(const libcamera::YamlObject &params);
+	virtual void initialise();
+	virtual void switchMode(CameraMode const &cameraMode, Metadata *metadata);
+	virtual void prepare(Metadata *imageMetadata);
+	virtual void process(StatisticsPtr &stats, Metadata *imageMetadata);
+	Metadata &getGlobalMetadata() const
+	{
+		return controller_->getGlobalMetadata();
+	}
+	const std::string &getTarget() const
+	{
+		return controller_->getTarget();
+	}
+	const Controller::HardwareConfig &getHardwareConfig() const
+	{
+		return controller_->getHardwareConfig();
+	}
+
+private:
+	Controller *controller_;
+};
+
+/*
+ * This code is for automatic registration of Front End algorithms with the
+ * system.
+ */
+
+typedef Algorithm *(*AlgoCreateFunc)(Controller *controller);
+struct RegisterAlgorithm {
+	RegisterAlgorithm(char const *name, AlgoCreateFunc createFunc);
+};
+std::map<std::string, AlgoCreateFunc> const &getAlgorithms();
+
+} /* namespace RPiController */