ipa: raspberrypi Store the target string in the controller

The target string may be used by algorithms to determine the running
hardware target.

Store the target string provided by the camera tuning files in the
controller state. Add a getTarget() member function to retrieve this
string.

Validate the correct hardware target ("bcm2835") during the IPA
initialisation phase.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/ipa/raspberrypi/controller/algorithm.h

@@ -41,6 +41,10 @@ public:
 	{
 		return controller_->getGlobalMetadata();
 	}
+	const std::string &getTarget() const
+	{
+		return controller_->getTarget();
+	}
 
 private:
 	Controller *controller_;

src/ipa/raspberrypi/controller/controller.cpp

@@ -38,6 +38,7 @@ int Controller::read(char const *filename)
 
 	std::unique_ptr<YamlObject> root = YamlParser::parse(file);
 	double version = (*root)["version"].get<double>(1.0);
+	target_ = (*root)["target"].get<std::string>("bcm2835");
 
 	if (version < 2.0) {
 		LOG(RPiController, Warning)
@@ -142,3 +143,8 @@ Algorithm *Controller::getAlgorithm(std::string const &name) const
 	}
 	return nullptr;
 }
+
+const std::string &Controller::getTarget() const
+{
+	return target_;
+}

src/ipa/raspberrypi/controller/controller.h

@@ -46,6 +46,7 @@ public:
 	void process(StatisticsPtr stats, Metadata *imageMetadata);
 	Metadata &getGlobalMetadata();
 	Algorithm *getAlgorithm(std::string const &name) const;
+	const std::string &getTarget() const;
 
 protected:
 	int createAlgorithm(const std::string &name, const libcamera::YamlObject &params);
@@ -53,6 +54,9 @@ protected:
 	Metadata globalMetadata_;
 	std::vector<AlgorithmPtr> algorithms_;
 	bool switchModeCalled_;
+
+private:
+	std::string target_;
 };
 
 } /* namespace RPiController */

src/ipa/raspberrypi/raspberrypi.cpp

@@ -266,6 +266,14 @@ int IPARPi::init(const IPASettings &settings, bool lensPresent, IPAInitResult *r
 		return ret;
 	}
 
+	const std::string &target = controller_.getTarget();
+	if (target != "bcm2835") {
+		LOG(IPARPI, Error)
+			<< "Tuning data file target returned \"" << target << "\""
+			<< ", expected \"bcm2835\"";
+		return -EINVAL;
+	}
+
 	lensPresent_ = lensPresent;
 
 	controller_.initialise();