pqm: add a callback for the PQM ping task and handle the ping interna…

…lly.

In order to avoid thread concurrency over the serial connection while
acquiring data and also pinging the board, we need to handle the ping
procedure internally. This can only be reproduced on Windows (my guess is
that the different implementation of libserialport for Windows vs UNIX
is the cause for this). Serial port calls return -995 at some point (which
is the error code for no I/O access. After this happens there is no
recovery for the serial connection and the plugin disconnects from the
device. This happens after a random amount of time.

This commit is a temporary workaround due to demand of users. But there is
a task in progress for development and investigation on the IIOPingTask
which should handle the plugin callback for the ping procedure but
should also move the ping management in the DeviceManager rather than
having it inside each plugin.

Signed-off-by: AlexandraTrifan <[email protected]>

iioutil/include/iioutil/iiopingtask.h

@@ -19,7 +19,7 @@ class SCOPY_IIOUTIL_EXPORT IIOPingTask : public QThread
 	IIOPingTask(iio_context *c, QObject *parent = nullptr);
 	~IIOPingTask();
 	virtual void run() override;
-
+	void setCallback(const std::function<bool(void)> callback);
 	static bool ping(iio_context *ctx);
 
 Q_SIGNALS:
@@ -29,6 +29,7 @@ class SCOPY_IIOUTIL_EXPORT IIOPingTask : public QThread
 protected:
 	iio_context *c;
 	bool enabled;
+	std::function<bool(void)> m_callback;
 };
 } // namespace scopy
 #endif // IIOPINGTASK_H

iioutil/src/iiopingtask.cpp

@@ -6,15 +6,20 @@ using namespace scopy;
 IIOPingTask::IIOPingTask(iio_context *c, QObject *parent)
 	: QThread(parent)
 	, c(c)
+	, m_callback(nullptr)
 {}
 
 IIOPingTask::~IIOPingTask() {}
 
 void IIOPingTask::run()
 {
-
+	bool ret;
 	enabled = true;
-	bool ret = ping(c);
+	if (m_callback) {
+		ret = m_callback();
+	} else {
+		ret = ping(c);
+	}
 
 	if(isInterruptionRequested())
 		return;
@@ -24,6 +29,11 @@ void IIOPingTask::run()
 		Q_EMIT pingFailed();
 }
 
+void IIOPingTask::setCallback(const std::function<bool()> callback)
+{
+	m_callback = callback;
+}
+
 bool IIOPingTask::ping(iio_context *ctx)
 {
 	auto dev = iio_context_get_device(ctx, 0);

plugins/pqm/include/pqm/acquisitionmanager.h

@@ -21,6 +21,7 @@ class AcquisitionManager : public QObject
 	~AcquisitionManager();
 
 public Q_SLOTS:
+	bool ping();
 	void toolEnabled(bool en, QString toolName);
 	void setConfigAttr(QMap<QString, QMap<QString, QString>>);
 Q_SIGNALS:
@@ -38,6 +39,7 @@ private Q_SLOTS:
 	bool readPqmAttributes();
 	bool readBufferedData();
 	void setData(QMap<QString, QMap<QString, QString>>);
+	bool pingInternal();
 
 	iio_context *m_ctx;
 	iio_buffer *m_buffer;
@@ -52,6 +54,8 @@ private Q_SLOTS:
 
 	bool m_attrHaveBeenRead = false;
 	bool m_buffHaveBeenRead = false;
+
+	std::atomic<bool> m_pingStatus;
 };
 } // namespace scopy::pqm
 

plugins/pqm/include/pqm/pqmcontroller.h

@@ -13,7 +13,7 @@ class PqmController : public QObject
 	PqmController(QString uri, QObject *parent = nullptr);
 	~PqmController();
 
-	void startPingTask(iio_context *ctx);
+	void startPingTask(iio_context *ctx, const std::function<bool(void)> callback);
 	void stopPingTask();
 
 Q_SIGNALS:

plugins/pqm/src/acquisitionmanager.cpp

@@ -10,6 +10,7 @@ AcquisitionManager::AcquisitionManager(iio_context *ctx, QObject *parent)
 	: QObject(parent)
 	, m_ctx(ctx)
 	, m_buffer(nullptr)
+	, m_pingStatus(true)
 {
 	m_readFw = new QFutureWatcher<void>(this);
 	m_setFw = new QFutureWatcher<void>(this);
@@ -50,6 +51,24 @@ AcquisitionManager::~AcquisitionManager()
 	m_pqmAttr.clear();
 }
 
+bool AcquisitionManager::pingInternal()
+{
+	auto dev = iio_context_get_device(m_ctx, 0);
+	const iio_device *test_device = nullptr;
+
+	int ret = iio_device_get_trigger(dev, &test_device);
+
+	if(ret < 0 && ret != -ENOENT) {
+		return false;
+	}
+	return true;
+}
+
+bool AcquisitionManager::ping()
+{
+	return m_pingStatus;
+}
+
 void AcquisitionManager::enableBufferChnls(iio_device *dev)
 {
 	int chnlsNo = iio_device_get_channels_count(dev);
@@ -86,11 +105,14 @@ void AcquisitionManager::futureReadData()
 void AcquisitionManager::readData()
 {
 	mutex.lock();
-	if(m_tools["rms"] || m_tools["harmonics"] || m_tools["settings"]) {
-		m_attrHaveBeenRead = readPqmAttributes();
-	}
-	if(m_tools["waveform"]) {
-		m_buffHaveBeenRead = readBufferedData();
+	m_pingStatus = pingInternal();
+	if(m_pingStatus) {
+		if(m_tools["rms"] || m_tools["harmonics"] || m_tools["settings"]) {
+			m_attrHaveBeenRead = readPqmAttributes();
+		}
+		if(m_tools["waveform"]) {
+			m_buffHaveBeenRead = readBufferedData();
+		}
 	}
 	mutex.unlock();
 }

plugins/pqm/src/pqmcontroller.cpp

@@ -13,13 +13,14 @@ PqmController::PqmController(QString uri, QObject *parent)
 
 PqmController::~PqmController() { stopPingTask(); }
 
-void PqmController::startPingTask(iio_context *ctx)
+void PqmController::startPingTask(iio_context *ctx, const std::function<bool(void)> callback)
 {
 	if(!ctx) {
 		qWarning(CAT_PQM_CONTROLLER) << "The context is unavailable!";
 		return;
 	}
 	m_pingTask = new IIOPingTask(ctx);
+	m_pingTask->setCallback(callback);
 	m_pingTimer = new CyclicalTask(m_pingTask);
 	connect(m_pingTask, &IIOPingTask::pingFailed, this, &PqmController::pingFailed);
 	connect(m_pingTask, &IIOPingTask::pingSuccess, this, &PqmController::pingSuccess);

plugins/pqm/src/pqmplugin.cpp

@@ -109,9 +109,10 @@ bool PQMPlugin::onConnect()
 	}
 	struct iio_context *ctx = conn->context();
 	connect(m_pqmController, &PqmController::pingFailed, this, &PQMPlugin::disconnectDevice);
-	m_pqmController->startPingTask(ctx);
-
 	m_acqManager = new AcquisitionManager(ctx, this);
+	auto fp = std::bind(&AcquisitionManager::ping, m_acqManager);
+	m_pqmController->startPingTask(ctx, fp);
+
 
 	RmsInstrument *rms = new RmsInstrument();
 	m_toolList[0]->setTool(rms);