feat: allow controller mapping to explicitely define data direction t…

…o a device

src/controllers/bulk/bulkcontroller.cpp

@@ -172,6 +172,12 @@ int BulkController::open() {
 
     if (m_pReader != nullptr) {
         qCWarning(m_logBase) << "BulkReader already present for" << getName();
+    } else if (m_pMapping &&
+            !(m_pMapping->getDeviceDirection() &
+                    LegacyControllerMapping::DeviceDirection::IN)) {
+        qDebug() << "The mapping for the bulk device" << getName()
+                 << "doesn't require reading the data. Ignoring BulkReader "
+                    "setup.";
     } else {
         m_pReader = new BulkReader(m_phandle, in_epaddr);
         m_pReader->setObjectName(QString("BulkReader %1").arg(getName()));
@@ -195,10 +201,12 @@ int BulkController::close() {
     qCInfo(m_logBase) << "Shutting down USB Bulk device" << getName();
 
     // Stop the reading thread
-    if (m_pReader == nullptr) {
+    if (m_pReader == nullptr &&
+            m_pMapping->getDeviceDirection() &
+                    LegacyControllerMapping::DeviceDirection::IN) {
         qCWarning(m_logBase) << "BulkReader not present for" << getName()
                              << "yet the device is open!";
-    } else {
+    } else if (m_pReader) {
         disconnect(m_pReader, &BulkReader::incomingData, this, &BulkController::receive);
         m_pReader->stop();
         qCInfo(m_logBase) << "  Waiting on reader to finish";
@@ -230,6 +238,14 @@ void BulkController::send(const QList<int>& data, unsigned int length) {
 }
 
 void BulkController::sendBytes(const QByteArray& data) {
+    VERIFY_OR_DEBUG_ASSERT(!m_pMapping ||
+            m_pMapping->getDeviceDirection() &
+                    LegacyControllerMapping::DeviceDirection::OUT) {
+        qDebug() << "The mapping for the bulk device" << getName()
+                 << "doesn't require sending data. Ignoring sending request.";
+        return;
+    }
+
     int ret;
     int transferred;
 

src/controllers/legacycontrollermapping.h

@@ -15,7 +15,7 @@
 class LegacyControllerMapping {
   public:
     LegacyControllerMapping()
-            : m_bDirty(false) {
+            : m_bDirty(false), m_deviceDirection(DeviceDirection::BIDIRECTIONNAL) {
     }
     virtual ~LegacyControllerMapping() = default;
 
@@ -32,6 +32,12 @@ class LegacyControllerMapping {
         bool builtin;
     };
 
+    enum DeviceDirection {
+        BIDIRECTIONNAL = 0b11,
+        IN = 0b10,
+        OUT = 0b01,
+    };
+
     /// Adds a script file to the list of controller scripts for this mapping.
     /// @param filename Name of the script file to add
     /// @param functionprefix The script's function prefix (or empty string)
@@ -54,6 +60,14 @@ class LegacyControllerMapping {
         return m_scripts;
     }
 
+    inline void setDeviceDirection(DeviceDirection aDeviceDirection) {
+        m_deviceDirection = aDeviceDirection;
+    }
+
+    inline DeviceDirection getDeviceDirection() const {
+        return m_deviceDirection;
+    }
+
     inline void setDirty(bool bDirty) {
         m_bDirty = bDirty;
     }
@@ -192,4 +206,5 @@ class LegacyControllerMapping {
     QString m_mixxxVersion;
 
     QList<ScriptFileInfo> m_scripts;
+    DeviceDirection m_deviceDirection;
 };

src/controllers/legacycontrollermappingfilehandler.cpp

@@ -126,6 +126,15 @@ void LegacyControllerMappingFileHandler::addScriptFilesToMapping(
     QString deviceId = controller.attribute("id", "");
     mapping->setDeviceId(deviceId);
 
+    QString deviceDirection = controller.attribute("direction", "").toLower();
+    if (deviceDirection == "in") {
+        mapping->setDeviceDirection(LegacyControllerMapping::DeviceDirection::IN);
+    } else if (deviceDirection == "out") {
+        mapping->setDeviceDirection(LegacyControllerMapping::DeviceDirection::OUT);
+    } else {
+        mapping->setDeviceDirection(LegacyControllerMapping::DeviceDirection::BIDIRECTIONNAL);
+    }
+
     // Build a list of script files to load
     QDomElement scriptFile = controller.firstChildElement("scriptfiles")
                                      .firstChildElement("file");