/*
* Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of the License "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description:
*
*/


/**
 @file
 @internalTechnology
*/

#include "cbulkonlytransport.h"
#include "cbulkonlytransportusbcscldd.h"
#include "usbmsshared.h"
#include "massstoragedebug.h"
#include "cusbmassstorageserver.h"


//This value defined in USB Mass Storage Bulk Only Transrt spec and not supposed to be changed
LOCAL_D const TInt KRequiredNumberOfEndpoints = 2; // in addition to endpoint 0.

LOCAL_D const TInt KUsbNumInterfacesOffset = 4;

#ifdef MSDC_MULTITHREADED
//Only used in DB. The first 2K of KMaxScBufferSize for sending CSW 
static const TUint32 KCswBufferSize = 2 * 1024;
#endif

////////////////////////////////////
/**
Called by CBulkOnlyTransportUsbcScLdd to create an instance of CControlInterfaceUsbcScLdd

@param aParent reference to the CBulkOnlyTransportUsbcScLdd
*/


CControlInterfaceUsbcScLdd* CControlInterfaceUsbcScLdd::NewL(CBulkOnlyTransportUsbcScLdd& aParent)
	{
	CControlInterfaceUsbcScLdd* self = new(ELeave) CControlInterfaceUsbcScLdd(aParent);
	CleanupStack::PushL(self);
	self->ConstructL();
	CActiveScheduler::Add(self);
	CleanupStack::Pop();
	return self;
	}


void CControlInterfaceUsbcScLdd::ConstructL()
	{
	}


/**
c'tor

@param aParent reference to the CBulkOnlyTransportUsbcScLdd
*/
CControlInterfaceUsbcScLdd::CControlInterfaceUsbcScLdd(CBulkOnlyTransportUsbcScLdd& aParent)
	:CActive(EPriorityStandard),
	 iParent(aParent),
	 iCurrentState(ENone)
	{
	}


/**
d'tor
*/
CControlInterfaceUsbcScLdd::~CControlInterfaceUsbcScLdd()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::~CControlInterfaceUsbcScLdd ");
	Cancel();
	iEp0Buf.Close();
	}

TInt CControlInterfaceUsbcScLdd::OpenEp0()
	{
	TInt res = iParent.Ldd().OpenEndpoint(iEp0Buf,0);
	return res;
	}

/**
Called by CBulkOnlyTransport HwStart to start control interface
*/
TInt CControlInterfaceUsbcScLdd::Start()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::Start ");
	TInt res = ReadEp0Data();
	return (res);
	}


/**
Called by desctructor of CBulkOnlyTransportUsbcScLdd to stop control interface
*/
void CControlInterfaceUsbcScLdd::Stop()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::Stop ");
	if (!IsActive())
		{
		__PRINT(_L("Not active\n"));
		return;
		}

	__PRINT(_L("\nStopping...\n"));


	iCurrentState = ENone;

	Cancel();
	}


/**
Cancel outstanding request (if any)
*/
void CControlInterfaceUsbcScLdd::DoCancel()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::DoCancel ");
	switch(iCurrentState)
		{
		case EReadEp0Data:
			iParent.Ldd().ReadCancel(KUsbcScEndpointZero);
			break;
		case ESendMaxLun:
			iParent.Ldd().WriteCancel(KUsbcScEndpointZero);
			break;
		default:
			__PRINT(_L("\nWrong state !\n"));
			__ASSERT_DEBUG(EFalse, User::Panic(KUsbMsSvrPncCat, EMsControlInterfaceBadState));
		}
	}


/**
Implement CControlInterfaceUsbcScLdd state machine
*/
void CControlInterfaceUsbcScLdd::RunL()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::RunL ");
	if (iStatus != KErrNone)
		{
		__PRINT1(_L("Error %d in RunL\n"), iStatus.Int());

		//read EP0  again
		ReadEp0Data();
		return;
		}

	ReadEp0Data();
	}

/**
Actual Read to RDevUsbcScClient BIL
*/
TInt CControlInterfaceUsbcScLdd::ReadUsbEp0()
	{
	iCurrentState = EReadEp0Data;
	iStatus = KRequestPending;
	return iEp0Buf.GetBuffer (iEp0Packet,iEp0Size,iEp0Zlp,iStatus);
	}


/**
Post a read request to EEndpoint0 to read request header
*/
TInt CControlInterfaceUsbcScLdd::ReadEp0Data()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::ReadEp0Data ");
	if (IsActive())
		{
		__PRINT(_L("Still active\n"));
		return KErrServerBusy;
		}

	TInt r = KErrNone;
	do
		{
		r = ReadUsbEp0();
		if (r == KErrCompletion)
			{
			iStatus = KErrNone;
			DecodeEp0Data();
			}
		else if (r == KErrNone)
			{
			SetActive();
			}
		} while (((r == KErrCompletion) || (r == TEndpointBuffer::KStateChange)) && (!IsActive()));
	return KErrNone;
	}


/**
Decode request header and do appropriate action - get max LUN info or post a reset request
*/
void CControlInterfaceUsbcScLdd::DecodeEp0Data()
	{
	__FNLOG("CControlInterfaceUsbcScLdd::DecodeEp0Data ");

	if (IsActive())
		{
		__PRINT(_L("Still active\n"));
		__ASSERT_DEBUG(EFalse, User::Panic(KUsbMsSvrPncCat, EMsControlInterfaceStillActive));
		return;
		}

	TPtrC8 ep0ReadDataPtr((TUint8*)iEp0Packet, iEp0Size);
	TInt err = iRequestHeader.Decode(ep0ReadDataPtr);

	if(err != KErrNone)
		return;

    switch(iRequestHeader.iRequest)
		{
		//
		// GET MAX LUN (0xFE)
		//
		case TUsbRequestHdr::EReqGetMaxLun:
			{
			__PRINT1(_L("DecodeEp0Data : 'Get Max LUN' Request MaxLun = %d"),iParent.MaxLun() );

            if (   iRequestHeader.iRequestType != 0xA1 //value from USB MS BOT spec
                || iRequestHeader.iIndex > 15
                || iRequestHeader.iValue != 0
                || iRequestHeader.iLength != 1)
                {
    		    __PRINT(_L("GetMaxLun command packet check error"));
                iParent.Ldd().EndpointZeroRequestError();
                break;
                }

			TPtr8* ep0WriteDataPtr = NULL;
			TUint ep0Length;
			iEp0Buf.GetInBufferRange(((TAny*&)ep0WriteDataPtr),ep0Length);
			ep0WriteDataPtr->SetLength(1);	//Return only 1 byte to host
			ep0WriteDataPtr->Fill(0);
			ep0WriteDataPtr->Fill(iParent.MaxLun());	// Supported Units
			TInt length = ep0WriteDataPtr->Length();
			err = iEp0Buf.WriteBuffer((TPtr8*)(ep0WriteDataPtr->Ptr()),length,ETrue,iStatus);

			iCurrentState = ESendMaxLun;
			SetActive();

			return;
			}
		//
		// RESET (0xFF)
		//
		case TUsbRequestHdr::EReqReset:
			{
			__PRINT(_L("DecodeEp0Data : 'Mass Storage Reset' Request"));

            if (   iRequestHeader.iRequestType != 0x21 //value from USB MS BOT spec
                || iRequestHeader.iIndex > 15
                || iRequestHeader.iValue != 0
                || iRequestHeader.iLength != 0)
                {
			    __PRINT(_L("MSC Reset command packet check error"));
                iParent.Ldd().EndpointZeroRequestError();
                break;
                }

			iParent.HwStop();
			iParent.Controller().Reset();
			iParent.HwStart(ETrue);

            err = iParent.Ldd().SendEp0StatusPacket();
			return;
			}
		//
		// Unknown?
		//
		default:
			{
			__PRINT(_L("DecodeEp0Data : Unknown Request"));

			}
		}
		ReadEp0Data();  //try to get another request
	}


//
// --- class CBulkOnlyTransportUsbcScLdd ---------------------------------------------------------
//

CBulkOnlyTransportUsbcScLdd::CBulkOnlyTransportUsbcScLdd(TInt aNumDrives,CUsbMassStorageController& aController)
	:CBulkOnlyTransport(aNumDrives, aController)
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::CBulkOnlyTransportUsbcScLdd");
	}

/**
Constructs the CBulkOnlyTransportUsbcScLdd object
*/
void CBulkOnlyTransportUsbcScLdd::ConstructL()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::ConstructL()");
	iControlInterface = CControlInterfaceUsbcScLdd::NewL(*this);
	iDeviceStateNotifier = CActiveDeviceStateNotifierBase::NewL(*this, *this);
	iChunk = new RChunk();
	CActiveScheduler::Add(this);
	}


CBulkOnlyTransportUsbcScLdd::~CBulkOnlyTransportUsbcScLdd()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::~CBulkOnlyTransportUsbcScLdd");
	if (iInterfaceConfigured)
		{
		TInt err = iSCReadEndpointBuf.Close(); 
		err = iSCWriteEndpointBuf.Close();
		delete iControlInterface ;
		delete iDeviceStateNotifier;
		delete iChunk;
		}
	}	

RDevUsbcScClient& CBulkOnlyTransportUsbcScLdd::Ldd()
	{
	return iLdd;
	}

/**
Set or unset configuration descriptor for USB MassStorage Bulk Only transport

@param aUnset indicate whether set or unset descriptor
@return KErrNone if operation was completed successfully, errorcode otherwise
*/
TInt CBulkOnlyTransportUsbcScLdd::SetupConfigurationDescriptor(TBool aUnset)
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::SetupConfigurationDescriptor");
	TInt ret(KErrNone);

	if ((ret = iLdd.Open(0)) != KErrNone)
		return ret;

	TInt configDescriptorSize(0);
	iLdd.GetConfigurationDescriptorSize(configDescriptorSize);
	if (static_cast<TUint>(configDescriptorSize) != KUsbDescSize_Config)
		{
		return KErrCorrupt;
		}

	TBuf8<KUsbDescSize_Config> configDescriptor;
	ret = iLdd.GetConfigurationDescriptor(configDescriptor);
	if (ret != KErrNone)
		{
		return ret;
		}

	// I beleive that other fields setted up during LDD initialisation
	if (aUnset)
		{
		--configDescriptor[KUsbNumInterfacesOffset];
		}
	else
		{
		++configDescriptor[KUsbNumInterfacesOffset];
		}
	ret = iLdd.SetConfigurationDescriptor(configDescriptor);

	if (aUnset)
		{
		iLdd.Close();
		}

	return ret;
	}

/**
Set up interface descriptor

@return KErrNone if operation was completed successfully, errorcode otherwise
*/
TInt CBulkOnlyTransportUsbcScLdd::SetupInterfaceDescriptors()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::SetupInterfaceDescriptors");
	// Device caps
	TUsbDeviceCaps d_caps;
	TInt ret = iLdd.DeviceCaps(d_caps);
	if (ret != KErrNone)
		{
		return ret;
		}
	TInt totalEndpoints = d_caps().iTotalEndpoints;
	if (totalEndpoints  < KRequiredNumberOfEndpoints)
		{
		return KErrHardwareNotAvailable;
		}

	// Endpoint caps
	TUsbcEndpointData data[KUsbcMaxEndpoints];
	TPtr8 dataptr(reinterpret_cast<TUint8*>(data), sizeof(data), sizeof(data));
	ret = iLdd.EndpointCaps(dataptr);
	if (ret != KErrNone)
		{
		return ret;
		}

	// Set the active interface
	TUsbcScInterfaceInfoBuf ifc;
	TInt ep_found = 0;
	TBool foundBulkIN = EFalse;
	TBool foundBulkOUT = EFalse;

	for (TInt i = 0; i < totalEndpoints ; i++)
		{
		const TUsbcEndpointCaps* caps = &data[i].iCaps;
		const TInt maxPacketSize = caps->MaxPacketSize();
		if (!foundBulkIN &&
			(caps->iTypesAndDir & (KUsbEpTypeBulk | KUsbEpDirIn)) == (KUsbEpTypeBulk | KUsbEpDirIn))
			{
			// InEndpoint is going to be our TX (IN, write) endpoint
			ifc().iEndpointData[0].iType = KUsbEpTypeBulk;
			ifc().iEndpointData[0].iDir  = KUsbEpDirIn;
			ifc().iEndpointData[0].iSize = maxPacketSize;
			ifc().iEndpointData[0].iInterval_Hs = 0;
			ifc().iEndpointData[0].iBufferSize = KMaxScBufferSize;
			foundBulkIN = ETrue;
			if (++ep_found == KRequiredNumberOfEndpoints)
				{
				break;
				}
			continue;
			}
		if (!foundBulkOUT &&
			(caps->iTypesAndDir & (KUsbEpTypeBulk | KUsbEpDirOut)) == (KUsbEpTypeBulk | KUsbEpDirOut))
			{
			// OutEndpoint is going to be our RX (OUT, read) endpoint
			ifc().iEndpointData[1].iType = KUsbEpTypeBulk;
			ifc().iEndpointData[1].iDir  = KUsbEpDirOut;
			ifc().iEndpointData[1].iSize = maxPacketSize;
			ifc().iEndpointData[1].iInterval_Hs = 0;
			ifc().iEndpointData[1].iBufferSize = KMaxScBufferSize;
			ifc().iEndpointData[1].iReadSize = KMaxScReadSize;

			foundBulkOUT = ETrue;
			if (++ep_found == KRequiredNumberOfEndpoints)
				{
				break;
				}
			continue;
			}
		}
	if (ep_found != KRequiredNumberOfEndpoints)
		{
		return KErrHardwareNotAvailable;
		}

	_LIT16(string, "USB Mass Storage Interface");
	ifc().iString = const_cast<TDesC16*>(&string);
	ifc().iTotalEndpointsUsed = KRequiredNumberOfEndpoints;
	ifc().iClass.iClassNum    = 0x08;	// Mass Storage
	ifc().iClass.iSubClassNum = 0x06;	// SCSI Transparent Command Set
	ifc().iClass.iProtocolNum = 0x50;	// Bulk Only Transport

	if (d_caps().iHighSpeed)
		{
		// Tell the Protocol about it, because it might want to do some
		// optimizing too.
		iProtocol->ReportHighSpeedDevice();
		}

	if ((ret = iLdd.SetInterface(0, ifc)) == KErrNone)
		{
		return (iLdd.FinalizeInterface(iChunk));
		}
	return ret;
	}

void CBulkOnlyTransportUsbcScLdd::ReleaseInterface()
	{
	iLdd.ReleaseInterface(0);
	}


TInt CBulkOnlyTransportUsbcScLdd::StartControlInterface()
	{
	return iControlInterface->Start();
	}

void CBulkOnlyTransportUsbcScLdd::CancelControlInterface()
	{
	iControlInterface->Cancel();
	}

void CBulkOnlyTransportUsbcScLdd::ActivateDeviceStateNotifier()
	{
	iDeviceStateNotifier->Activate();
	}

void CBulkOnlyTransportUsbcScLdd::CancelDeviceStateNotifier()
	{
	iDeviceStateNotifier->Cancel();
	}


void CBulkOnlyTransportUsbcScLdd::CancelReadWriteRequests()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::CancelReadWriteRequests");
	TUsbcScChunkHeader chunkHeader(*iChunk);
	for (TInt i = 0; i < chunkHeader.iAltSettings->iNumOfAltSettings; i++)
		{
		TInt8* endpoint = (TInt8*) (chunkHeader.iAltSettings->iAltTableOffset[i] + (TInt) iChunk->Base());
		TInt numOfEps = chunkHeader.GetNumberOfEndpoints(i);
        __ASSERT_DEBUG(numOfEps >= 0, User::Invariant());
		for (TInt j = 1; j <= numOfEps; j++)
			{
			TUsbcScHdrEndpointRecord* endpointInf = (TUsbcScHdrEndpointRecord*) &(endpoint[j * chunkHeader.iAltSettings->iEpRecordSize]);
			if (endpointInf->Direction() == KUsbScHdrEpDirectionOut)
				{
				iLdd.ReadCancel(endpointInf->iBufferNo);
				}
			if (endpointInf->Direction() == KUsbScHdrEpDirectionIn)
				{
				iLdd.WriteCancel(endpointInf->iBufferNo);
				}
			}
		}
	}

void CBulkOnlyTransportUsbcScLdd::AllocateEndpointResources()
	{
	TUsbcScChunkHeader chunkHeader(*iChunk);
	for (TInt i = 0; i < chunkHeader.iAltSettings->iNumOfAltSettings; i++)
		{
		TInt8* endpoint = (TInt8*) (chunkHeader.iAltSettings->iAltTableOffset[i] + (TInt) iChunk->Base()); 

		for (TInt j = 1; j <= chunkHeader.GetNumberOfEndpoints(i); j++) 
			{
			TUsbcScHdrEndpointRecord* endpointInf = (TUsbcScHdrEndpointRecord*) &(endpoint[j * chunkHeader.iAltSettings->iEpRecordSize]);
			if (endpointInf->Direction() == KUsbScHdrEpDirectionOut)
				{
				iOutEndpoint = j;
				}
			if (endpointInf->Direction() == KUsbScHdrEpDirectionIn)
				{
				iInEndpoint = j;
				}
			}
		}
		
	__PRINT(_L("CBulkOnlyTransportUsbcScLdd::Start  - Setting up DMA and double buffering\n"));
	// Set up DMA if possible (errors are non-critical)
	TInt err = iLdd.AllocateEndpointResource(iOutEndpoint, EUsbcEndpointResourceDMA);
	if (err != KErrNone)
		{
		__PRINT1(_L("Set DMA on OUT endpoint failed with error code: %d"), err);
		}
	err = iLdd.AllocateEndpointResource(iInEndpoint, EUsbcEndpointResourceDMA);
	if (err != KErrNone)
		{
		__PRINT1(_L("Set DMA on IN endpoint failed with error code: %d"), err);
		}

	// Set up Double Buffering if possible (errors are non-critical)
	err = iLdd.AllocateEndpointResource(iOutEndpoint, EUsbcEndpointResourceDoubleBuffering);
	if (err != KErrNone)
		{
		__PRINT1(_L("Set Double Buffering on OUT endpoint failed with error code: %d"), err);
		}
	err = iLdd.AllocateEndpointResource(iInEndpoint, EUsbcEndpointResourceDoubleBuffering);
	if (err != KErrNone)
		{
		__PRINT1(_L("Set Double Buffering on IN endpoint failed with error code: %d"), err);
		}

	
	err = OpenEndpoints();
	}

TInt CBulkOnlyTransportUsbcScLdd::OpenEndpoints()
	{
	TInt res = iLdd.OpenEndpoint(iSCReadEndpointBuf, iOutEndpoint);
	if (res == KErrNone)
		{
		res = iLdd.OpenEndpoint(iSCWriteEndpointBuf, iInEndpoint);
		if (res == KErrNone)
			{
			iSCWriteEndpointBuf.GetInBufferRange((TAny*&)iDataPtr, iInBufferLength);
			res = iControlInterface->OpenEp0();
			}
		return res;
		}

	return res;
	}


TInt CBulkOnlyTransportUsbcScLdd::GetDeviceStatus(TUsbcDeviceState& deviceStatus)
	{
	return iLdd.DeviceStatus(deviceStatus);
	}

void CBulkOnlyTransportUsbcScLdd::FlushData()
	{
	// Intentionally Left Blank Do Nothing 
	}

/**
 * Read out rest data from OutEndpoint and discard them
 */
void CBulkOnlyTransportUsbcScLdd::ReadAndDiscardData(TInt /*aBytes*/)
	{
	__FNLOG("CBulkOnlyTransport::ReadAndDiscardData");
	TRequestStatus status;
	TInt r = KErrNone; // Lets assume there is no data
	do
		{
		iSCReadSize = 0;
		status = KErrNone;
		r = iSCReadEndpointBuf.TakeBuffer(iSCReadData,iSCReadSize,iReadZlp,status);
		iSCReadEndpointBuf.Expire();
		}
	while (r == KErrCompletion);

	if (r == KErrNone)
		{
		TRequestStatus* stat = &status;
		User::RequestComplete(stat, KErrNone);
		}
	}

/**
Called by the protocol to determine how many bytes of data are available in the read buffer.

@return The number of bytes available in the read buffer
*/
TInt CBulkOnlyTransportUsbcScLdd::BytesAvailable()
	{
	// Intentionally Left Blank Do Nothing 
	return 0;
	}

void CBulkOnlyTransportUsbcScLdd::StallEndpointAndWaitForClear()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::StallEndpointAndWaitForClear");

	// Now stall this endpoint
	__PRINT1(_L("Stalling endpoint %d"), iInEndpoint);
	TInt r = iLdd.HaltEndpoint(iInEndpoint);
	if (r != KErrNone)
		{
		__PRINT2(_L("Error: stalling ep %d failed: %d"), iInEndpoint, r);
		}
	TEndpointState ep_state;
	TInt i = 0;
	do
		{
		// Wait for 10ms before checking the ep status
		User::After(10000);
		iLdd.EndpointStatus(iInEndpoint, ep_state);
		if (++i >= 550)
			{
			// 5.5 secs should be enough (see 9.2.6.1 Request Processing Timing)
			__PRINT1(_L("Error: Checked for ep %d de-stall for 5.5s - giving up now"), iInEndpoint);
			// We can now only hope for a Reset Recovery
			return;
			}
		} while ((ep_state == EEndpointStateStalled) && iStarted);
	__PRINT2(_L("Checked for ep %d de-stall: %d time(s)"), iInEndpoint, i);
	}

/**
Read CBW data from the host and decode it.
*/
void CBulkOnlyTransportUsbcScLdd::ReadCBW()
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::ReadCBW");
	if (IsActive())
		{
		__PRINT(_L("Still active\n"));
		__ASSERT_DEBUG(EFalse, User::Panic(KUsbMsSvrPncCat, EMsBulkOnlyStillActive)); 
		return;
		}
	TInt r = KErrNone;
	do
		{
		r = ReadUsb();
		if ((r == KErrCompletion) && (iSCReadSize == KCbwLength))  
			{
			iCurrentState = EWaitForCBW;
			iStatus = KErrNone;
			DecodeCBW();
			iSCReadSize = 0;
			}
		else if (r == KErrNone)
			{
			iCurrentState = EWaitForCBW;
			SetActive();
			}
		else if ((r == KErrCompletion) && (iSCReadSize != KCbwLength))
			{
			ExpireData(iSCReadData);
			}
		}while ((r == KErrCompletion) && (!IsActive()));
	}

void CBulkOnlyTransportUsbcScLdd::ExpireData(TAny* aAddress)
	{
	if (aAddress)
		{
		iSCReadEndpointBuf.Expire(aAddress);
		}
	else
		{
		iSCReadEndpointBuf.Expire();
		}
	}

void CBulkOnlyTransportUsbcScLdd::ProcessCbwEvent()
	{
	ReadCBW();
	}

/**
Request data form the host for the protocol

@param aLength amount of data (in bytes) to be received from the host
*/
void CBulkOnlyTransportUsbcScLdd::ReadData(TUint /*aLength*/)
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::ReadData");
	if (IsActive())
		{
		__PRINT(_L("Still active\n"));
		__ASSERT_DEBUG(EFalse, User::Panic(KUsbMsSvrPncCat, EMsBulkOnlyStillActive));
		return;
		}
	TInt r = KErrNone;
	do
		{
		r = ReadUsb();
		iCurrentState = EReadingData;
		if (r == KErrCompletion)
			{
			iReadBufPtr.Set((TUint8*) iSCReadData, iSCReadSize, iSCReadSize);
			iStatus = KErrNone;
			ProcessDataFromHost();
			iSCReadSize = 0;
			}
		else if (r == KErrNone)
			{
			iSCReadSize = 0;
			SetActive();
			}

		}while ((r == KErrCompletion) && (!IsActive()));
	}

void CBulkOnlyTransportUsbcScLdd::ProcessDataFromHost()
	{
	TInt ret = KErrNone;
		{
		if (iReadSetUp)
			{
			ret = iProtocol->ReadComplete(KErrNone);
			}
#ifndef MSDC_MULTITHREADED
		ExpireData(iSCReadData);
#endif
		TUint deviceDataLength = iSCReadSize; // What was written to the disk // static_cast<TUint>(iReadBuf.Length());
		if(ret == KErrCompletion)
			{
			// The protocol has indicated with KErrCompletion that sufficient
			// data is available in the buffer to process the transfer immediately.

			//iDataResidue is initially set to host data length as we do not know how much data is there in the 'LDD transfer'. 
			//After a TakeBuffer call, iSCReadSize in updated and set to deviceDataLength
			iDataResidue -= deviceDataLength;
			}
		else
			{
			iDataResidue -= deviceDataLength;

			// The protocol has indicated that transfer is
			// complete, so send the CSW response to the host.
			iReadSetUp = EFalse;

			if (ret != KErrNone)
				{
				iCmdStatus = ECommandFailed;
				}

			if (iDataResidue)
				{
				__PRINT(_L("Discarding residue"));
				// we have to read as much data as available that host PC sends;
				// otherwise, bulk-out endpoint will need to keep sending NAK back.
				ReadAndDiscardData(iDataResidue); 
				}

			SendCSW(iCbwTag, iDataResidue, iCmdStatus);
			}
		}
	}

void CBulkOnlyTransportUsbcScLdd::WriteUsb(TRequestStatus& aStatus, TPtrC8& aDes, TUint aLength, TBool aZlpRequired)
	{
	TUint aOffset = (TUint) aDes.Ptr() - (TUint) iChunk->Base();
	iSCWriteEndpointBuf.WriteBuffer(aOffset, aLength, aZlpRequired, aStatus);
	}

void CBulkOnlyTransportUsbcScLdd::SetCbwPtr()
	{
	iCbwBufPtr.Set((TUint8*)iSCReadData, iSCReadSize);
	}

TPtr8& CBulkOnlyTransportUsbcScLdd::SetCommandBufPtr(TUint aLength)
	{
	TPtr8 writeBuf((TUint8*) iDataPtr, aLength);
	iCommandBufPtr.Set(writeBuf);
	return iCommandBufPtr;
	}

void CBulkOnlyTransportUsbcScLdd::SetReadDataBufPtr(TUint /*aLength*/)
	{
	// Do nothing for now 
	}

TPtr8& CBulkOnlyTransportUsbcScLdd::SetDataBufPtr()
	{
	TPtr8 writeBuf((TUint8*) iDataPtr, iInBufferLength);
	iDataBufPtr.Set(writeBuf);
	return iDataBufPtr;
	}

void CBulkOnlyTransportUsbcScLdd::SetPaddingBufPtr(TUint aLength)
	{
	TPtr8 writeBuf((TUint8*) iDataPtr, aLength, aLength);
	iPaddingBufPtr.Set(writeBuf);
	}

void CBulkOnlyTransportUsbcScLdd::SetCswBufPtr(TUint aLength)
	{
	TPtr8 writeBuf((TUint8*) iDataPtr, aLength, aLength);
	iCswBufPtr.Set(writeBuf);
	}

void CBulkOnlyTransportUsbcScLdd::ProcessReadingDataEvent()
	{
	ReadData();
	}

TInt CBulkOnlyTransportUsbcScLdd::ReadUsb(TUint /*aLength*/)
	{
	__FNLOG("CBulkOnlyTransportUsbcScLdd::ReadUSB");
	return iSCReadEndpointBuf.TakeBuffer(iSCReadData,iSCReadSize,iReadZlp,iStatus);
	}

void CBulkOnlyTransportUsbcScLdd::DiscardData(TUint aLength)
	{
	TUint c = 0;
	TRequestStatus status;
	TInt r = KErrNone;
	while (c < aLength)
		{
		iSCReadSize = 0;
		status = KErrNone;
		r = iSCReadEndpointBuf.TakeBuffer(iSCReadData,iSCReadSize,iReadZlp,status);
		c += iSCReadSize;
		if (r == KErrNone)
			User::WaitForRequest(status);
		if (r == KErrCompletion)
			{
			iSCReadEndpointBuf.Expire();
			}
		iSCReadSize = 0;
		}
	}

void CBulkOnlyTransportUsbcScLdd::WriteToClient(TUint aLength)
	{
	TUint c = 0;
	TRequestStatus status;
	TInt r = KErrNone;
	while (c < aLength)
		{
		iSCReadSize = 0;
		status = KErrNone;
		r = iSCReadEndpointBuf.TakeBuffer(iSCReadData,iSCReadSize,iReadZlp,status);
		c += iSCReadSize;
		iProtocol->ReadComplete(KErrGeneral);
		if (r == KErrNone)
			User::WaitForRequest(status);
		if (r == KErrCompletion)
			{
			iSCReadEndpointBuf.Expire();
			}
		iSCReadSize = 0;
		}
	}

#ifdef MSDC_MULTITHREADED
void CBulkOnlyTransportUsbcScLdd::GetBufferPointers(TPtr8& aDes1, TPtr8& aDes2)
	{
	//for DB
	TUint length = (TUint) (iInBufferLength - KCswBufferSize) / 2;

	TUint8* start = (TUint8*) (iDataPtr) + KCswBufferSize ; // 'first' buffer
	aDes1.Set(start, length, length);

	start = (TUint8*) (iDataPtr) + KCswBufferSize + length; // 'second' buffer
	aDes2.Set(start, length, length);
	}
#endif

void CBulkOnlyTransportUsbcScLdd::Activate(TRequestStatus& aStatus, TUint& aDeviceState)
    {
	iLdd.AlternateDeviceStatusNotify(aStatus, aDeviceState);
    }


void CBulkOnlyTransportUsbcScLdd::Cancel()
    {
	iLdd.AlternateDeviceStatusNotifyCancel();
    }




