diff -r d3e8e7d462dd -r f92a4f87e424 usbmgmt/usbmgr/device/classdrivers/ncm/classimplementation/ncmpktdrv/pktdrv/src/ncmbuffermanager.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/usbmgmt/usbmgr/device/classdrivers/ncm/classimplementation/ncmpktdrv/pktdrv/src/ncmbuffermanager.cpp	Tue Aug 31 17:01:47 2010 +0300
@@ -0,0 +1,170 @@
+/*
+* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "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
+*/
+
+
+#include "ncmbuffermanager.h"
+#include "OstTraceDefinitions.h"
+#ifdef OST_TRACE_COMPILER_IN_USE
+#include "ncmbuffermanagerTraces.h"
+#endif
+
+
+
+
+// if there are KCongestionCount buffers will notify networking to stop sending
+// if there are at least KUnCongestionCount, will notify networking to start sending
+const TInt KCongestionCount = 1;
+const TInt KUnCongestionCount = 3;
+
+
+
+// ======== MEMBER FUNCTIONS ========
+//
+
+CNcmBufferManager* CNcmBufferManager::NewL()
+    {
+    OstTraceFunctionEntry0( CNCMBUFFERMANAGER_NEWL_ENTRY );
+    CNcmBufferManager *self = new (ELeave) CNcmBufferManager();
+    OstTraceFunctionExit0( CNCMBUFFERMANAGER_NEWL_EXIT );
+    return self;
+    }
+
+CNcmBufferManager::~CNcmBufferManager()
+    {
+    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_CNCMBUFFERMANAGER_ENTRY, this );
+    iFreeQueue.Reset();
+    OstTraceFunctionExit1( CNCMBUFFERMANAGER_CNCMBUFFERMANAGER_EXIT, this );
+    }
+
+//
+// get a buffer block from manager
+//
+TInt CNcmBufferManager::GetBuffer(TNcmBuffer& aBuffer)
+    {
+	OstTraceFunctionEntry1( CNCMBUFFERMANAGER_GETBUFFER_ENTRY, this );
+	
+    TInt count = iFreeQueue.Count();
+    TInt ret = KErrNone;
+
+    if (count == 0)
+        {
+        OstTraceFunctionExit1( CNCMBUFFERMANAGER_GETBUFFER_EXIT, this );
+        return KErrNoBuffer;
+        }
+    else if (count == KCongestionCount)
+        {
+        iIsCongestion = ETrue;
+        ret = KErrCongestion;
+        }
+    aBuffer = iFreeQueue[0];
+    iFreeQueue.Remove(0);
+    OstTraceFunctionExit1( CNCMBUFFERMANAGER_GETBUFFER_EXIT_DUP1, this );
+    return ret;
+    }
+
+//
+// free a buffer block to manager
+//
+void CNcmBufferManager::FreeBuffer(const TNcmBuffer& aBuffer)
+    {
+    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_FREEBUFFER_ENTRY, this );
+    iFreeQueue.Append(aBuffer);  
+    int count = iFreeQueue.Count();
+    iFreeQueue[count-1].iLen = 0;
+    if (count == KUnCongestionCount)
+        {
+        iIsCongestion = EFalse;
+        }
+    OstTraceFunctionExit1( CNCMBUFFERMANAGER_FREEBUFFER_EXIT, this );
+    }
+
+//
+// set the whole buffer area to create buffer blocks
+//
+void CNcmBufferManager::InitBufferArea(TAny* aBuf, TInt aLength)
+    {
+    OstTrace1( TRACE_NORMAL, CNCMBUFFERMANAGER_INITBUFFERAREA, "CNcmBufferManager::InitBufferArea aLength=%d", aLength );    
+    iBuf = (TUint8*)aBuf;
+    iLen = aLength;
+    }
+
+//
+// set the size of a buffer block, create buffer blocks on the buffer area
+//
+TInt CNcmBufferManager::SetBufferCellSize(TInt aSize)
+    {
+    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_ENTRY, this );
+
+//    buffer block size must be aligned with KAlignSize to make the each buffer start align with KAlignSize 
+    iCellSize = (aSize+iAlignSize-1)&~(iAlignSize-1);
+    OstTraceExt2( TRACE_NORMAL, CNCMBUFFERMANAGER_SETBUFFERCELLSIZE, "CNcmBufferManager::SetBufferCellSize aSize=%d, iCellSize=%d", aSize, iCellSize );
+
+//   buffer area got from share chunk LDD may not align, make it align to KAlignSize first
+    TUint32 buf = (TUint)iBuf;
+    buf = (buf+iAlignSize-1)&~(iAlignSize-1);
+    TUint8* alignbuf = (TUint8*)buf;
+    TUint32 offset = buf - (TUint)iBuf;
+    
+    int count = (iLen-offset)/iCellSize;
+    iFreeQueue.Reset();
+    if (count < KUnCongestionCount)
+        {        
+        OstTrace1( TRACE_FATAL, CNCMBUFFERMANAGER_SETBUFFERCELLSIZE1, "the buffer cell size is too big and create too less buffers %d", count );
+        OstTraceFunctionExit1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_EXIT, this );
+        return KErrUnknown;
+        }
+
+    TNcmBuffer ncmbuf;
+    for (TInt i=0 ; i<count ; i++)
+        {
+        ncmbuf.iPtr = alignbuf+i*iCellSize;
+        ncmbuf.iLen = 0;
+        ncmbuf.iMaxLength = iCellSize;
+        iFreeQueue.Append(ncmbuf);
+        }
+    iIsCongestion = EFalse;
+    OstTraceFunctionExit1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_EXIT_DUP1, this );
+    return KErrNone;
+    }
+
+CNcmBufferManager::CNcmBufferManager()
+    {
+    iIsCongestion = EFalse;
+    }
+
+//
+// if there is not enough buffer blocks, return ETrue and will start flow control in networking
+//
+
+TBool CNcmBufferManager::IsCongestion()
+    {
+    OstTrace1( TRACE_NORMAL, CNCMBUFFERMANAGER_ISCONGESTION, "CNcmBufferManager::FreeBufferCount %d", iFreeQueue.Count() );
+    return iIsCongestion;
+    }
+
+TInt CNcmBufferManager::RequiredBufferCount()
+    {
+    return KUnCongestionCount;
+    }
+
+