kernel/eka/drivers/usbho/usbdi_utils/zerocopytransferstrategy.h
author Mike Kinghan <mikek@symbian.org>
Tue, 16 Nov 2010 14:39:21 +0000
branchGCC_SURGE
changeset 303 9b85206a602c
parent 102 ef2a444a7410
permissions -rw-r--r--
We need a way to pass flags to rombuilds in Raptor via extension flm interfaces, so that the CPP pass of the rom input files can be informed what toolchain we are building with and conditionally include or exclude files depending on whether the toolchain could build them.

// Copyright (c) 2007-2009 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
 @internalComponent
*/

#ifndef ZEROCOPYTRANSFERSTRATEGY_H
#define ZEROCOPYTRANSFERSTRATEGY_H

#include "usbtransferstrategy.h"


NONSHARABLE_CLASS(RUsbZeroCopyTransferStrategy) : public RUsbTransferStrategy
	{
public:
	RUsbZeroCopyTransferStrategy();
	virtual TInt RegisterTransferDescriptor(RUsbTransferDescriptor& aTransferDesc, TInt aRequiredSize, TUint aStartAlignment, TInt aRequiredMaxPackets);
	virtual void ResetTransferDescriptors();
	virtual TInt InitialiseTransferDescriptors(RUsbInterface& aInterface);

	virtual void Close();

public: // Interrupt transfer descriptor methods
	virtual TPtr8	IntrWritableBuffer(TInt aHandle);
	virtual void	IntrSaveData(TInt aHandle, TInt aLength);
	virtual void	IntrSetZlpStatus(TInt aHandle, RUsbTransferDescriptor::TZlpStatus aZlpStatus);
	virtual TPtrC8	IntrBuffer(TInt aHandle) const;
public: // Bulk transfer descriptor methods
	virtual TPtr8	BulkWritableBuffer(TInt aHandle);
	virtual void	BulkSaveData(TInt aHandle, TInt aLength);
	virtual void	BulkSetZlpStatus(TInt aHandle, RUsbTransferDescriptor::TZlpStatus aZlpStatus);
	virtual TPtrC8	BulkBuffer(TInt aHandle) const;
public: // Isochronous transfer descriptor methods
	virtual void	IsocReset(TInt aHandle);
	virtual TPacketLengths IsocLengths(TInt aHandle);
	virtual TPacketResults IsocResults(TInt aHandle);
	virtual TInt	IsocMaxPacketSize(TInt aHandle);
	virtual TPtr8	IsocWritablePackets(TInt aHandle, TInt aWriteHandle, TInt aNumPacketsRequested, TInt& aMaxNumPacketsAbleToWrite);
	virtual TInt	IsocSaveMultiple(TInt aHandle, TInt aWriteHandle, TInt aNumOfPackets);
	virtual TPtrC8	IsocPackets(TInt aHandle, TInt aFirstPacketIndex, TInt aNumPacketsRequested, TInt& aNumPacketsReturned) const;
	virtual void	IsocReceivePackets(TInt aHandle, TInt aNumOfPackets);


private: // Standard (Bulk, Ctrl and Intr) Buffer methods
	TPtr8	WritableBuffer(TInt aHandle);
	void	SaveData(TInt aHandle, TInt aLength);
	void	SetZlpStatus(TInt aHandle, RUsbTransferDescriptor::TZlpStatus aZlpStatus);
	TPtrC8	Buffer(TInt aHandle) const;

private: // Isoc Buffer methods
	void	Reset(TInt aHandle);
	TPacketLengths Lengths(TInt aHandle);
	TPacketResults Results(TInt aHandle);
	TInt	MaxPacketSize(TInt aHandle);
	TPtr8	WritablePackets(TInt aHandle, TInt aWriteHandle, TInt aNumPacketsRequested, TInt& aMaxNumPacketsAbleToWrite);
	TInt	SaveMultiple(TInt aHandle, TInt aWriteHandle, TInt aNumOfPackets);
	TPtrC8	Packets(TInt aHandle, TInt aFirstPacketIndex, TInt aNumPacketsRequested, TInt& aNumPacketsReturned) const;
	void	ReceivePackets(TInt aHandle, TInt aNumOfPackets);
	
private:
	NONSHARABLE_STRUCT(TUsbTransferDescriptorDetails)
		{
        TUsbTransferDescriptorDetails(RUsbTransferDescriptor&, TInt, TUint, TInt);
		RUsbTransferDescriptor& iTransferDesc;
		const TInt iRequiredSize;
		TUint iRequiredAlignment;
		const TInt iRequiredMaxPackets;
		// Members to aid internal logic
		TInt iAssignedOffset;
		TInt iLengthsOffset; // Only applicable to isoc
		TInt iReqLenOffset; // Only applicable to isoc
		TInt iResultsOffset; // Only applicable to isoc
		TInt iNumElements; // Only applicable to isoc
		};

private:
	TInt CalculateDataLayout(TInt& aCurrentOffset, TInt& aNumStandardTransfers, TInt& aNumIsocTransfers, TInt& aNumIsocElements);
	void CalculateMetaDataLayout(TInt& aCurrentOffset, TInt& aMetaDataStart, TInt aNumStandardTransfers, TInt aNumIsocTransfers, TInt aNumIsocElements);
	void InitialiseMetaData(TInt aMetaDataOffset, TInt aNumStandardTransfers, TInt aNumIsocTransfers, TInt aNumIsocElements);
	TInt UsedPackets(TInt aHeaderOffset);
	TBool IsPowerOfTwo(TUint aNumber);
	TInt IncNeededToAlign(TInt aOffset, TUint aAlignment);
	static TBool CompareTransferDescriptor(const RUsbTransferDescriptor* aTransferDesc, const TUsbTransferDescriptorDetails& aDetails);

private: //Calculate additional alignment related methods
	TInt GetMaximumMaxPacketSize(TInt& aMaxMaxBulk, TInt& aMaxMaxInterrupt);
	TInt CaculateAdditionalAlignment(TInt aCurrentOffset, TInt aMaxMaxBulk, TInt aMaxMaxInterrupt, TUsbTransferDescriptorDetails& aTransferDetails);
private:
	RArray<TUsbTransferDescriptorDetails> iRegisteredTransfers;

private:
	RUsbInterface* iInterfaceHandle;
	RChunk iChunk;
	TInt iBaseOffset;
	TInt iPageSize;
	};

#endif // ZEROCOPYTRANSFERSTRATEGY_H