audioclass.c

基于ADSP-BF535 USB驱动应用程序

						else if ((newAltSetting == ALTSETTING_FOR_AUDIOSTREAMING_IDLE) && (gIsPlaybackActive))
							{
								Dprintf ("Stopping Playback!");
								gIsPlaybackActive = false;
								//Disarm the endpoint
								DisarmEndpoint (EP1, EP_OUT);
								UnprepareEP (EP1);

#if PROVIDE_FEEDBACK
								DisarmEndpoint (EP2, EP_IN);
								UnprepareEP (EP2);
#endif //PROVIDE_FEEDBACK

								//ToDo: Cleanup the codec so that it stops playing
								AC97_DisablePlayback();
							}
					}
			}
		else
			{
				if (gIsPlaybackActive)
					{
						gIsPlaybackActive = false;
						//Disarm the endpoint
						DisarmEndpoint (EP1, EP_OUT);
						UnprepareEP (EP1);
#if PROVIDE_FEEDBACK
						DisarmEndpoint (EP2, EP_IN);
						UnprepareEP (EP2);
#endif //PROVIDE_FEEDBACK
						//ToDo: Cleanup the codec so that it stops playing
						AC97_DisablePlayback();
					}
				//We should disarm the endpoint(s) at this point!
			}
			
		return true;
	}



/*------------------------------------------------------------
*	OnInTransferComplete
*
*	Parameters:  
*		endpointNumber - the endpoint on which the transfer was completed.
*
*	Globals Used:
*		none
*
*	Description:
*		This routine is called when a IN transfer is completed on one of the
*		endpoints. 
*
*	Returns:
*		Nothing
*
*------------------------------------------------------------*/
void OnInTransferComplete (UCHAR endpointNumber)
	{
		void *pFeedbackData;

#if PROVIDE_FEEDBACK
		if ((endpointNumber == EP2) && (gIsPlaybackActive))
			{
				if (PrepareINEPForXFer (EP2, &pFeedbackData))
					{
						memcpy (pFeedbackData, &gFeedbackData, FEEDBACK_PACKET_SIZE);
						//Arm the endpoint!
						ArmEndpoint (EP2, EP_IN);
					}
			}
#endif //PROVIDE_FEEDBACK
	}


/*------------------------------------------------------------
*	OnOutTransferComplete
*
*	Parameters:  
*		endpointNumber - the endpoint on which the transfer was completed.
*		buffer - data buffer where the data was received
*		numBytesReceived - number of bytes received
*		wasPCAsserted - was the PC(packet complete) asserted when the TC interrup
*			came in. If not, this could be a possible problem???
*
*	Globals Used:
*		gIsPlaybackActive
*
*	Description:
*		This routine is called when a transfer is completed on one of the
*		out endpoints. In turn, this routine saves the received data in
*		a cyclic buffer.
*
*	Returns:
*		true to tell the isr to recycle the dma buffer, and setup
*		things for the next transfer, false to tell the isr to
*		free up the dma buffer, and disarm the endpoint.
*
*------------------------------------------------------------*/
bool OnOutTransferComplete (UCHAR endpointNumber, void *buffer, UINT numBytesReceived, bool wasPCAsserted)
	{

		UINT inThisPass, currentTail, headTailDistance;

		if (!gIsPlaybackActive)
			return (false);

		gTimeoutCount = 0;

		//gDebugNumTransfers++;
		//gDebugTotalTransferLength += numBytesReceived;
			
		if ((gDataBufferHead + numBytesReceived) >= MAX_DATA_BUFFER_SIZE)
			{
				inThisPass = MAX_DATA_BUFFER_SIZE - gDataBufferHead;
				memcpy (&gDataBuffer[gDataBufferHead], buffer, inThisPass);
				memcpy (&gDataBuffer, (UCHAR *)buffer + inThisPass, numBytesReceived - inThisPass);
				gDataBufferHead = numBytesReceived - inThisPass;
			}
		else
			{
				memcpy (&gDataBuffer[gDataBufferHead], buffer, numBytesReceived);
				gDataBufferHead += numBytesReceived;
			}


		if (gEnablePlaybackCountdown != 0)
			{
				gEnablePlaybackCountdown--;
				if (gEnablePlaybackCountdown == 0)
					AC97_EnablePlayback ();
			}
#if PROVIDE_FEEDBACK
		else
			{
				//Check to see if we need to change the feedback Fs?

				//Need to latch this value, as the SPORT0 interrupt
				//might change it any time!
				currentTail = gDataBufferTail;

				if (gDataBufferHead >= currentTail)
					headTailDistance = gDataBufferHead - currentTail;
				else
					headTailDistance = (MAX_DATA_BUFFER_SIZE - currentTail) + gDataBufferHead;
				
				if (headTailDistance > ((PLAYBACK_DELAY + 1) * 4 * 48))
					{
						gFeedbackData = FEEDBACK_FREQUENCY_PLEASE_SLOWDOWN;
						//Dprintf2 ("Slow: Head:%d, Tail: %d", gDataBufferHead, currentTail);
					}
				else if (headTailDistance < ((PLAYBACK_DELAY -1) * 4 * 48))
					{
						gFeedbackData = FEEDBACK_FREQUENCY_PLEASE_HURRY;
						//Dprintf2 ("Hurry: Head:%d, Tail: %d", gDataBufferHead, currentTail);
					}
				else
					gFeedbackData = FEEDBACK_FREQUENCY_NORMAL;

			}
#endif //PROVIDE_FEEDBACK

		return (true);
		

	}


/*------------------------------------------------------------
*	OnNAKSent
*
*	Parameters:  
*		endpointNumber - endpoint where the NAK was sent.
*
*	Globals Used:
*		gPrepareReport
*
*	Description:
*		This routine is called when the device has sent a NAK in response
*		to an IN or OUT request while the DMA buffer for that endpoint
*		has been emptied. Please note that this will only be called in
*		response to an "expected" direction request - IN request for
*		endpoints setup as IN endpoints and OUT request for endpoints
*		setup as OUT endpoints. 
*
*	Returns:
*		Nothing
*
*------------------------------------------------------------*/
void OnNAKSent (UCHAR endpointNumber)
	{
	}




/*------------------------------------------------------------
*	OnSuspend
*
*	Parameters:  
*
*	Globals Used:
*		gpOnSuspend
*
*	Description:
*		This routine will be called when USBDriver detects a
*		suspend condition. Currently, it quites the AC97 and forwards
*		the call to the client!
*
*	Returns:
*		Nothing.
*
*------------------------------------------------------------*/
void OnSuspend (void)
	{
		gIsPlaybackActive = false;
		AC97_DisablePlayback ();
		if (gpOnSuspend)
			(gpOnSuspend)();
	}



/*------------------------------------------------------------
*	OnResume
*
*	Parameters:  
*
*	Globals Used:
*		gpOnResume
*
*	Description:
*		This routine will be called when the USBDriver detects that
*		the bus is out of suspend. Currently, it simply forwards
*		the call to the client!
*
*	Returns:
*		Nothing.
*
*------------------------------------------------------------*/
void OnResume (void)
	{
		if (gpOnResume)
			(gpOnResume) ();
	}


/*------------------------------------------------------------
*	OnSOF
*
*	Parameters:  None.
*
*	Globals Used:
*		gIsPlaybackActive, gTimeoutCount, gDataBufferHead, gDataBufferTail
*		gEnablePlaybackCountdown
*
*	Description:
*		This routine will be called when the USBDriver receives an SOF
*		interrupt. It is mainly used to see if the transfers have timed out.
*
*	Returns:
*		Nothing.
*
*------------------------------------------------------------*/
void OnSOF (void)
	{
		if (!gIsPlaybackActive)
			return;

		if (gTimeoutCount > 3)
			{
				if (gEnablePlaybackCountdown == 0)
					{
						AC97_DisablePlayback ();
						//init the pointers
						gDataBufferHead = gDataBufferTail = 0;
						gEnablePlaybackCountdown = PLAYBACK_DELAY;
					}
			}
		else
			gTimeoutCount++;

	}


/*------------------------------------------------------------
*	OnReset
*
*	Parameters:  
*
*	Globals Used:
*		gpOnReset
*
*	Description:
*		This routine will be called when the USBDriver detects reset
*		signalling on the bus. Currently, it quiets the codec and forwards
*		the call to the client!
*
*	Returns:
*		Nothing.
*
*------------------------------------------------------------*/
void OnReset (void)
	{
		gIsPlaybackActive = false;
		AC97_DisablePlayback ();
		if (gpOnReset)
			(gpOnReset)();
	}


/*----------------------------------------------------------------------------------
* $Log: AudioClass.c,v $
* Revision 1.8  2003/01/17 00:53:10  Devendra
* Commented out a few Dprintfs
*
* Revision 1.7  2003/01/17 00:52:03  Devendra
* - BugFix: Set Volume requests were not handled properly.
* - Changed the feedback speed up and slow down rates to be more aggressive.
*
* Revision 1.6  2003/01/16 19:10:05  Devendra
* - Added code to set AC97 registers for mute and volume controls based on Host requests..
* - Added code to detect "timeout" (no isoch. packets coming in) by implementing OnSOF callback.
* - Added support for AudioClass to perform non-ISR(foreground) tasks.
* - Exposed playback active state variable.
*
* Revision 1.5  2003/01/15 01:35:14  Devendra
* Added code to provide feedback to pace control  the isoch. pipe.
*
* Revision 1.4  2003/01/13 19:56:18  Devendra
* Moved the data buffer to ac97.c
* Added code to enuser "distance" between buffer head and tail (latency).
* BugFix: buffer copy was not proper.
* Separated Descriptors to a separate header.
*
* Revision 1.2  2003/01/10 01:53:55  Devendra
* - Added support for receiving a playback stream on isoch. endpoint and storing the data in a cyclic buffer.
*
* Revision 1.1  2003/01/09 01:16:35  Devendra
* First Rev of AudioClass - have the device enumerated as audio device, and the volume control and mute are functional!
*
* Revision 1.1  2002/10/31 00:30:59  Devendra
* Moved all files in one folder to avoid IDE related problems.
*
* Revision 1.3  2002/10/30 02:36:40  Devendra
* - Added more abstraction to HIDCLASS. So that it's possible to build
*   different devices without making any changes to the HIDCLASS module.
* - Added proper support for handling USB SUSPEND, RESUME, and RESET events.
*
* Revision 1.2  2002/10/22 17:50:54  Devendra
* - Changed Product ID to 0x0005
*
* Revision 1.1  2002/10/22 17:23:38  Devendra
* Rearranged file locations.
*
* Revision 1.6  2002/10/14 05:16:48  Devendra
* Updated version number.
*
* Revision 1.5  2002/10/14 05:16:04  Devendra
* - Custom Device now using Feature reports for I/O
* - Added compiler define/project configuration to switch between mouse and custom device.
*
* Revision 1.4  2002/10/14 01:33:15  Devendra
* Got "custom" device functional with buttons and lights!
*
* Revision 1.3  2002/10/09 17:09:32  Devendra
* - Added support for handling IN endpoints.
* - Added HID descriptors (HID and HID Report)
* - Modified the Interface descriptors to comply to HID Class Spec.
* - Added functionality to use the push-buttons on the Eagle-35 as a mouse (for buttons as well as for movement).
* - The device is now a fully functioning USB Mouse!
*
* Revision 1.2  2002/10/08 19:57:02  Devendra
* - Added specific callbacks for getting Device, Config, and String descriptors.
* - BugFix: Max. Packet Size was not being set correctly in ArmEndpoint.
* - Added internal buffer based logging to allow real-time "printfs".
* - Added String descriptors.
*
* Revision 1.1  2002/09/20 06:51:30  Devendra
* First Rev.
*
*
*---------------------------------------------------------------------------------*/