Added new NO_CLASS_DRIVER_AUTOFLUSH compile time option to disable automatic flushing of interfaces when the USB management tasks for each driver is called.

The MIDI class drivers now automatically flushes the MIDI interface when the MIDI class driver's USBTask() function is called.

LUFA/Drivers/USB/Class/Device/CDC.c

@@ -148,7 +148,9 @@ void CDC_Device_USBTask(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 	if ((USB_DeviceState != DEVICE_STATE_Configured) || !(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS))
 	  return;
 
+	#if !defined(NO_CLASS_DRIVER_AUTOFLUSH)
 	CDC_Device_Flush(CDCInterfaceInfo);
+	#endif
 }
 
 uint8_t CDC_Device_SendString(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo,

LUFA/Drivers/USB/Class/Device/MIDI.c

@@ -76,6 +76,16 @@ bool MIDI_Device_ConfigureEndpoints(USB_ClassInfo_MIDI_Device_t* const MIDIInter
 	return true;
 }
 
+void MIDI_Device_USBTask(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo)
+{
+	if (USB_DeviceState != DEVICE_STATE_Configured)
+	  return;
+
+	#if !defined(NO_CLASS_DRIVER_AUTOFLUSH)
+	MIDI_Device_Flush(MIDIInterfaceInfo);
+	#endif
+}
+
 uint8_t MIDI_Device_SendEventPacket(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo,
                                     const MIDI_EventPacket_t* const Event)
 {

LUFA/Drivers/USB/Class/Device/MIDI.h

@@ -120,6 +120,13 @@
 			 */
 			bool MIDI_Device_ConfigureEndpoints(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
 
+			/** General management task for a given MIDI class interface, required for the correct operation of the interface. This should
+			 *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
+			 *
+			 *  \param[in,out] MIDIInterfaceInfo  Pointer to a structure containing a MIDI Class configuration and state.
+			 */
+			void MIDI_Device_USBTask(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
+
 			/** Sends a MIDI event packet to the host. If no host is connected, the event packet is discarded. Events are queued into the
 			 *  endpoint bank until either the endpoint bank is full, or \ref MIDI_Device_Flush() is called. This allows for multiple
 			 *  MIDI events to be packed into a single endpoint packet, increasing data throughput.
@@ -160,17 +167,6 @@
 			                                    MIDI_EventPacket_t* const Event) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 
 		/* Inline Functions: */
-			/** General management task for a given MIDI class interface, required for the correct operation of the interface. This should
-			 *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
-			 *
-			 *  \param[in,out] MIDIInterfaceInfo  Pointer to a structure containing a MIDI Class configuration and state.
-			 */
-			static inline void MIDI_Device_USBTask(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
-			static inline void MIDI_Device_USBTask(USB_ClassInfo_MIDI_Device_t* const MIDIInterfaceInfo)
-			{
-				(void)MIDIInterfaceInfo;
-			}
-
 			/** Processes incoming control requests from the host, that are directed to the given MIDI class interface. This should be
 			 *  linked to the library \ref EVENT_USB_Device_UnhandledControlRequest() event.
 			 *

LUFA/Drivers/USB/Class/Device/MassStorage.c

@@ -126,7 +126,7 @@ void MS_Device_USBTask(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo)
 			  Endpoint_SelectEndpoint(MSInterfaceInfo->Config.DataINEndpointNumber);
 
 			MSInterfaceInfo->State.CommandStatus.Status = CALLBACK_MS_Device_SCSICommandReceived(MSInterfaceInfo) ?
-			                                                                 MS_SCSI_COMMAND_Pass : MS_SCSI_COMMAND_Fail;
+			                                               MS_SCSI_COMMAND_Pass : MS_SCSI_COMMAND_Fail;
 			MSInterfaceInfo->State.CommandStatus.Signature           = MS_CSW_SIGNATURE;
 			MSInterfaceInfo->State.CommandStatus.Tag                 = MSInterfaceInfo->State.CommandBlock.Tag;
 			MSInterfaceInfo->State.CommandStatus.DataTransferResidue = MSInterfaceInfo->State.CommandBlock.DataTransferLength;

LUFA/Drivers/USB/Class/Host/CDC.c

@@ -226,7 +226,9 @@ void CDC_Host_USBTask(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)
 
 	Pipe_Freeze();
 
+	#if !defined(NO_CLASS_DRIVER_AUTOFLUSH)
 	CDC_Host_Flush(CDCInterfaceInfo);
+	#endif
 }
 
 uint8_t CDC_Host_SetLineEncoding(USB_ClassInfo_CDC_Host_t* const CDCInterfaceInfo)

LUFA/Drivers/USB/Class/Host/MIDI.c

@@ -141,6 +141,16 @@ static uint8_t DCOMP_MIDI_Host_NextMIDIStreamingDataEndpoint(void* const Current
 	return DESCRIPTOR_SEARCH_NotFound;
 }
 
+void MIDI_Host_USBTask(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo)
+{
+	if ((USB_HostState != HOST_STATE_Configured) || !(MIDIInterfaceInfo->State.IsActive))
+	  return;
+
+	#if !defined(NO_CLASS_DRIVER_AUTOFLUSH)
+	MIDI_Host_Flush(MIDIInterfaceInfo);
+	#endif	
+}
+
 uint8_t MIDI_Host_Flush(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo)
 {
 	if ((USB_HostState != HOST_STATE_Configured) || !(MIDIInterfaceInfo->State.IsActive))

LUFA/Drivers/USB/Class/Host/MIDI.h

@@ -137,6 +137,13 @@
 			                                 uint16_t ConfigDescriptorSize,
 			                                 void* DeviceConfigDescriptor) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(3);
 
+			/** General management task for a given MIDI host class interface, required for the correct operation of the interface. This should
+			 *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
+			 *
+			 *  \param[in,out] MIDIInterfaceInfo  Pointer to a structure containing an MIDI Class host configuration and state.
+			 */
+			void MIDI_Host_USBTask(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
+
 			/** Sends a MIDI event packet to the device. If no device is connected, the event packet is discarded.
 			 *
 			 *  \pre This function must only be called when the Host state machine is in the \ref HOST_STATE_Configured state or the
@@ -174,18 +181,6 @@
 			bool MIDI_Host_ReceiveEventPacket(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo,
 			                                  MIDI_EventPacket_t* const Event) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 
-		/* Inline Functions: */
-			/** General management task for a given MIDI host class interface, required for the correct operation of the interface. This should
-			 *  be called frequently in the main program loop, before the master USB management task \ref USB_USBTask().
-			 *
-			 *  \param[in,out] MIDIInterfaceInfo  Pointer to a structure containing an MIDI Class host configuration and state.
-			 */
-			static inline void MIDI_Host_USBTask(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo) ATTR_NON_NULL_PTR_ARG(1);
-			static inline void MIDI_Host_USBTask(USB_ClassInfo_MIDI_Host_t* const MIDIInterfaceInfo)
-			{
-				(void)MIDIInterfaceInfo;
-			}
-
 	/* Private Interface - For use in library only: */
 	#if !defined(__DOXYGEN__)
 		/* Function Prototypes: */

LUFA/Drivers/USB/Class/Host/Printer.c

@@ -142,7 +142,12 @@ static uint8_t DCOMP_PRNT_Host_NextPRNTInterfaceEndpoint(void* CurrentDescriptor
 
 void PRNT_Host_USBTask(USB_ClassInfo_PRNT_Host_t* const PRNTInterfaceInfo)
 {
+	if ((USB_HostState != HOST_STATE_Configured) || !(PRNTInterfaceInfo->State.IsActive))
+	  return;
+
+	#if !defined(NO_CLASS_DRIVER_AUTOFLUSH)
 	PRNT_Host_Flush(PRNTInterfaceInfo);
+	#endif
 }
 
 uint8_t PRNT_Host_SetBidirectionalMode(USB_ClassInfo_PRNT_Host_t* const PRNTInterfaceInfo)

LUFA/ManPages/ChangeLog.txt

@@ -28,6 +28,8 @@
   *  - Added board hardware driver support for the Maximus board (thanks to the PSGroove team)
   *  - Added board hardware driver support for the Minimus board (thanks to the PSGroove team)
   *  - Added default test tone generation mode to the Device mode AudioInput demos
+  *  - Added new NO_CLASS_DRIVER_AUTOFLUSH compile time option to disable automatic flushing of interfaces when the USB management
+  *    tasks for each driver is called
   *
   *  <b>Changed:</b>
   *  - Removed complicated logic for the Endpoint_ConfigureEndpoint() function to use inlined or function called versions
@@ -58,6 +60,7 @@
   *  - All USB class drivers are now automatically included when LUFA/Drivers/USB.h is included, and no longer need to be seperately included
   *  - All LowLevel demos changed to use the constants and types defined in the USB class drivers
   *  - Changed AudioInput and AudioOutput demos to reload the next sample via an interrupt rather than polling the sample timer
+  *  - The MIDI class drivers now automatically flushes the MIDI interface when the MIDI class driver's USBTask() function is called
   *
   *  <b>Fixed:</b>
   *  - Fixed USB_GetHIDReportItemInfo() function modifying the given report item's data when the report item does not exist

LUFA/ManPages/CompileTimeTokens.txt

@@ -67,6 +67,12 @@
  *  and their sizes calculated/stored into the resultant processed report structure. If not defined, this defaults to the value indicated in
  *  the HID.h file documentation.
  *
+ *  <b>NO_CLASS_DRIVER_AUTOFLUSH</b>
+ *  Many of the device and host mode class drivers automatically flush any data waiting to be written to an interface, when the corresponding
+ *  USB management task is executed. This is usually desirable to ensure that any queued data is sent as soon as possible once and new data is
+ *  constructed in the main program loop. However, if flushing is to be controlled manually by the user application via the *_Flush() commands,
+ *  the compile time token may be defined in the application's makefile to disable automatic flushing during calls to the class driver USB
+ *  management tasks.
  *
  *  \section Sec_SummaryUSBTokens General USB Driver Related Tokens
  *  This section describes compile tokens which affect USB driver stack as a whole in the LUFA library.