USBDevice: factored out a function to release OUT eps

Author: cmaglie

cores/arduino/USB/PluggableUSB.h

@@ -35,7 +35,7 @@ class PluggableUSBModule {
   virtual bool setup(USBSetup& setup) = 0;
   virtual int getInterface(uint8_t* interfaceCount) = 0;
   virtual int getDescriptor(USBSetup& setup) = 0;
-  virtual void handleEndpoint(int ep) {/* Do nothing */}
+  virtual void handleEndpoint(int ep) { (void)ep;/* Do nothing */}
   virtual uint8_t getShortName(char *name) { name[0] = 'A'+pluggedInterface; return 1; }
 
   uint8_t pluggedInterface;

cores/arduino/USB/SAMD21_USBDevice.h

@@ -180,6 +180,15 @@ class USBDevice_SAMD21G18x {
 	inline void epBank0EnableAutoZLP(ep_t ep)  { EP[ep].DeviceDescBank[0].PCKSIZE.bit.AUTO_ZLP = 1; }
 	inline void epBank1EnableAutoZLP(ep_t ep)  { EP[ep].DeviceDescBank[1].PCKSIZE.bit.AUTO_ZLP = 1; }
 
+	// USB Device Endpoint transactions helpers
+	// ----------------------------------------
+
+	inline void epReleaseOutBank0(ep_t ep, uint16_t s) {
+		epBank0SetMultiPacketSize(ep, s);
+		epBank0SetByteCount(ep, 0);
+		epBank0ResetReady(ep);
+	}
+
 private:
 	// USB Device registers
 	UsbDevice &usb;
@@ -243,6 +252,7 @@ class DoubleBufferedEPOutHandler : public EPHandler {
 		usbd.epBank0SetType(ep, 3); // BULK OUT
 
 		usbd.epBank0SetAddress(ep, const_cast<uint8_t *>(data0));
+		usbd.epBank0EnableTransferComplete(ep);
 
 		release();
 	}
@@ -394,11 +404,7 @@ class DoubleBufferedEPOutHandler : public EPHandler {
 	}
 
 	void release() {
-		// Release OUT EP
-		usbd.epBank0EnableTransferComplete(ep);
-		usbd.epBank0SetMultiPacketSize(ep, size);
-		usbd.epBank0SetByteCount(ep, 0);
-		usbd.epBank0ResetReady(ep);
+		usbd.epReleaseOutBank0(ep, size);
 	}
 
 private:

cores/arduino/USB/USBCore.cpp

@@ -542,11 +542,7 @@ void USBDeviceClass::initEP(uint32_t ep, uint32_t config)
 		usbd.epBank1SetType(ep, 1); // CONTROL IN
 
 		// Release OUT EP
-		usbd.epBank0SetMultiPacketSize(ep, 64);
-		usbd.epBank0SetByteCount(ep, 0);
-
-		// NAK on endpoint OUT, the bank is full.
-		usbd.epBank0SetReady(ep);
+		usbd.epReleaseOutBank0(ep, 64);
 	}
 }