os/kernelhwsrv/kernel/eka/drivers/ecomm/uart16550.cpp
author sl
Tue, 10 Jun 2014 14:32:02 +0200
changeset 1 260cb5ec6c19
permissions -rw-r--r--
Update contrib.
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// Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).
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// All rights reserved.
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// This component and the accompanying materials are made available
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// under the terms of the License "Eclipse Public License v1.0"
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// which accompanies this distribution, and is available
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// at the URL "http://www.eclipse.org/legal/epl-v10.html".
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//
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// Initial Contributors:
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// Nokia Corporation - initial contribution.
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//
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// Contributors:
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//
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// Description:
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// e32\drivers\ecomm\uart16550.cpp
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// PDD for 16550 UART
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// 
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//
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#include <drivers/comm.h>
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#include <assp.h>
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#include <var_defs.h>
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#include <uart16550.h>
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#include <e32hal.h>
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_LIT(KPddName,"Comm.16550");
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#define __COMMS_MACHINE_CODED__
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#ifdef __COMMS_MACHINE_CODED__
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#define DBASE_VPTR_OFFSET	4
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#define RX_ISR_VT_OFFSET	0x24
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#define CHK_TXB_VT_OFFSET	0x28
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#define STATE_ISR_VT_OFFSET	0x2C
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#endif
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// needs ldd version..
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const TInt KMinimumLddMajorVersion=1;
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const TInt KMinimumLddMinorVersion=1;
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const TInt KMinimumLddBuild=122;
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// configuration data
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static const TUint16 BaudRateDivisor[19] =
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	{
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	2304,	1536,	1047,	860,	768,	384,	192,	96,
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	64,		58,		48,		32,		24,		16,		12,		6,
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	3,		2,		1
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	};
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class DDriverComm : public DPhysicalDevice
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	{
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public:
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	DDriverComm();
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	virtual TInt Install();
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	virtual void GetCaps(TDes8 &aDes) const;
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	virtual TInt Create(DBase*& aChannel, TInt aUnit, const TDesC8* anInfo, const TVersion &aVer);
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	virtual TInt Validate(TInt aUnit, const TDesC8* anInfo, const TVersion &aVer);
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public:
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	TDynamicDfcQue* iDfcQ;
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	};
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class DComm16550 : public DComm
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	{
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public:
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	DComm16550();
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	~DComm16550();
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	TInt DoCreate(TInt aUnit, const TDesC8* anInfo);
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public:
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	virtual TInt Start();
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	virtual void Stop(TStopMode aMode);
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	virtual void Break(TBool aState);
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	virtual void EnableTransmit();
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	virtual TUint Signals() const;
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	virtual void SetSignals(TUint aSetMask,TUint aClearMask);
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	virtual TInt ValidateConfig(const TCommConfigV01 &aConfig) const;
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	virtual void Configure(TCommConfigV01 &aConfig);
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	virtual void Caps(TDes8 &aCaps) const;
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	virtual TInt DisableIrqs();
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	virtual void RestoreIrqs(TInt aIrq);
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	virtual TDfcQue* DfcQ(TInt aUnit);
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	virtual void CheckConfig(TCommConfigV01& aConfig);
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public:
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	static void Isr(TAny* aPtr);
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public:
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	TInt iInterruptId;
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	TInt iUnit;
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	T16550Uart* iUart;
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	};
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DDriverComm::DDriverComm()
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//
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// Constructor
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//
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	{
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	iUnitsMask=~(0xffffffffu<<KNum16550Uarts);
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	iVersion=TVersion(KCommsMajorVersionNumber,KCommsMinorVersionNumber,KCommsBuildVersionNumber);
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	}
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TInt DDriverComm::Install()
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//
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// Install the driver
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//
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	{
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	// Allocate a kernel thread to run the DFC 
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	TInt r = Kern::DynamicDfcQCreate(iDfcQ, KUart16550ThreadPriority, KUar16550tDriverThread);
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	if (r == KErrNone)
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		{
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		iDfcQ->SetRealtimeState(ERealtimeStateOff);  
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		r = SetName(&KPddName);
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		}
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	return r;
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	}
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/**
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  Destructor
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*/
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DDriverComm::~DDriverComm()
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	{
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	if (iDfcQ)
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		iDfcQ->Destroy();
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	}
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void Get16550CommsCaps(TDes8& aCaps, TInt aUnit)
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	{
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	TCommCaps3 capsBuf;
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	TCommCapsV03 &c=capsBuf();
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	c.iRate=KCapsBps110|KCapsBps150|KCapsBps300|KCapsBps600\
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		|KCapsBps1200|KCapsBps2400|KCapsBps4800|KCapsBps9600\
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		|KCapsBps19200|KCapsBps38400|KCapsBps57600|KCapsBps115200;
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	c.iDataBits=KCapsData5|KCapsData6|KCapsData7|KCapsData8;
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	c.iStopBits=KCapsStop1|KCapsStop2;
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	c.iParity=KCapsParityNone|KCapsParityEven|KCapsParityOdd|KCapsParityMark|KCapsParitySpace;
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	c.iHandshake=KCapsObeyXoffSupported|KCapsSendXoffSupported|
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					KCapsObeyCTSSupported|KCapsFailCTSSupported|
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					KCapsObeyDSRSupported|KCapsFailDSRSupported|
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					KCapsObeyDCDSupported|KCapsFailDCDSupported|
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					KCapsFreeRTSSupported|KCapsFreeDTRSupported;
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	c.iSIR=0;
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	c.iSignals=KCapsSignalCTSSupported|KCapsSignalRTSSupported|KCapsSignalDTRSupported|
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						KCapsSignalDSRSupported|KCapsSignalDCDSupported|KCapsSignalRNGSupported;
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	c.iFifo=KCapsHasFifo;
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	c.iNotificationCaps=KNotifyDataAvailableSupported|KNotifySignalsChangeSupported;
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	c.iRoleCaps=0;
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	c.iFlowControlCaps=0;
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	c.iBreakSupported=ETrue;
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	aCaps.FillZ(aCaps.MaxLength());
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	aCaps=capsBuf.Left(Min(capsBuf.Length(),aCaps.MaxLength()));
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	}
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void DDriverComm::GetCaps(TDes8 &aDes) const
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//
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// Return the drivers capabilities
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//
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	{
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	Get16550CommsCaps(aDes, 0);
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	}
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TInt DDriverComm::Create(DBase*& aChannel, TInt aUnit, const TDesC8* anInfo, const TVersion& aVer)
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//
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// Create a driver
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//
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	{
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	DComm16550* pD=new DComm16550;
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	aChannel=pD;
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	TInt r=KErrNoMemory;
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	if (pD)
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		r=pD->DoCreate(aUnit,anInfo);
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	return r;
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	}
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TInt DDriverComm::Validate(TInt aUnit, const TDesC8* /*anInfo*/, const TVersion& aVer)
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//
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//	Validate the requested configuration
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//
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	{
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	if ((!Kern::QueryVersionSupported(iVersion,aVer)) || (!Kern::QueryVersionSupported(aVer,TVersion(KMinimumLddMajorVersion,KMinimumLddMinorVersion,KMinimumLddBuild))))
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		return KErrNotSupported;
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	if (aUnit<0 || aUnit>=KNum16550Uarts)
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		return KErrNotSupported;
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	return KErrNone;
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	}
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DComm16550::DComm16550()
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//
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// Constructor
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//
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	{
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//	iTransmitting=EFalse;
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	iInterruptId=-1;		// -1 means not bound
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	}
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DComm16550::~DComm16550()
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//
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// Destructor
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//
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	{
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	if (iInterruptId>=0)
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		Interrupt::Unbind(iInterruptId);
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	}
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TInt DComm16550::DoCreate(TInt aUnit, const TDesC8* /*anInfo*/)
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//
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// Sets up the PDD
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//
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	{
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	iUnit=aUnit;
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	TInt irq=IrqFromUnit(aUnit);
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	// bind to UART interrupt
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	TInt r=Interrupt::Bind(irq,Isr,this);
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	if (r==KErrNone)
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		{
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		iInterruptId=irq;
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		iUart=UartFromUnit(aUnit);
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		iUart->SetIER(0);
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		iUart->SetLCR(0);
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		iUart->SetFCR(0);
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		iUart->SetMCR(0);
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		}
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	return r;
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	}
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TDfcQue* DComm16550::DfcQ(TInt /*aUnit*/)
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//
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// Return the DFC queue to be used for this device
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// For PC cards, use the PC card controller thread for the socket in question.
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//
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	{
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	return iDfcQ;
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	}
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TInt DComm16550::Start()
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//
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// Start receiving characters
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//
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	{
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	// if EnableTransmit() called before Start()
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	iTransmitting=EFalse;
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	iUart->SetIER(K16550IER_RDAI|K16550IER_RLSI|K16550IER_MSI);
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	iLdd->UpdateSignals(Signals());
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	Interrupt::Enable(iInterruptId);
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	return KErrNone;
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	}
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TBool FinishedTransmitting(TAny* aPtr)
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	{
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	DComm16550& d=*(DComm16550*)aPtr;
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	return d.iUart->TestLSR(K16550LSR_TxIdle);
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	}
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void DComm16550::Stop(TStopMode aMode)
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//
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// Stop receiving characters
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//
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	{
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	switch (aMode)
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		{
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		case EStopNormal:
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		case EStopPwrDown:
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			iUart->SetIER(0);
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			Interrupt::Disable(iInterruptId);
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			iTransmitting=EFalse;
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			// wait for uart to stop tranmitting
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			Kern::PollingWait(FinishedTransmitting,this,3,100);
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			break;
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		case  EStopEmergency:
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			iUart->SetIER(0);
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			Interrupt::Disable(iInterruptId);
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			iTransmitting=EFalse;
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			break;
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		}
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	}
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void DComm16550::Break(TBool aState)
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//
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// Start or stop the uart breaking
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//
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	{
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	if (aState)
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		iUart->ModifyLCR(0,K16550LCR_TxBreak);
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	else
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		iUart->ModifyLCR(K16550LCR_TxBreak,0);
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	}
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void DComm16550::EnableTransmit()
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//
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// Start sending characters.
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//
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	{
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	TBool tx = (TBool)__e32_atomic_swp_ord32(&iTransmitting, 1);
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	if (tx)
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		return;
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	iUart->ModifyIER(0,K16550IER_THREI);
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	}
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TUint DComm16550::Signals() const
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//
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// Read and translate the modem lines
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//
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	{
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	TUint msr=iUart->MSR();
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	msr=((msr>>4)&0x0f);			// true input signals
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	TUint sig=msr & 3;				// CTS,DSR OK
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	if (msr & 4)
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		sig|=KSignalRNG;			// swap DCD,RNG
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	if (msr & 8)
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		sig|=KSignalDCD;
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	return sig;
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	}
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void DComm16550::SetSignals(TUint aSetMask, TUint aClearMask)
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//
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// Set signals.
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//
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	{
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	TUint set=0;
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	TUint clear=0;
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	if (aSetMask & KSignalRTS)
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		set|=K16550MCR_RTS;
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	if (aSetMask & KSignalDTR)
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		set|=K16550MCR_DTR;
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	if (aClearMask & KSignalRTS)
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		clear|=K16550MCR_RTS;
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	if (aClearMask & KSignalDTR)
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		clear|=K16550MCR_DTR;
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	iUart->ModifyMCR(clear,set);
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	}
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TInt DComm16550::ValidateConfig(const TCommConfigV01 &aConfig) const
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//
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// Check a config structure.
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//
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	{
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	if (aConfig.iSIREnable==ESIREnable)
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		return KErrNotSupported;
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	switch (aConfig.iParity)
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		{
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		case EParityNone:
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		case EParityOdd:
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		case EParityEven:
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		case EParityMark:
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		case EParitySpace:
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			break;
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		default:
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			return KErrNotSupported;
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		}
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	if (TUint(aConfig.iRate)>TUint(EBps115200))
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		return KErrNotSupported;
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	return KErrNone;
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	}
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void DComm16550::CheckConfig(TCommConfigV01& aConfig)
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	{
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	// do nothing
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	}
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TInt DComm16550::DisableIrqs()
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//
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// Disable normal interrupts
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//
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	{
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	return NKern::DisableInterrupts(1);
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	}
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void DComm16550::RestoreIrqs(TInt aLevel)
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//
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// Restore normal interrupts
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//
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	{
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	NKern::RestoreInterrupts(aLevel);
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	}
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void DComm16550::Configure(TCommConfigV01 &aConfig)
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//
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// Set up the Uart
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//
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	{
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	// wait for uart to stop tranmitting
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	Kern::PollingWait(FinishedTransmitting,this,3,100);
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	TUint lcr=0;
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	switch (aConfig.iDataBits)
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		{
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		case EData5: lcr=K16550LCR_Data5; break;
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		case EData6: lcr=K16550LCR_Data6; break;
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		case EData7: lcr=K16550LCR_Data7; break;
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		case EData8: lcr=K16550LCR_Data8; break;
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		}
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	switch (aConfig.iStopBits)
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		{
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		case EStop1: break;
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		case EStop2: lcr|=K16550LCR_Stop2; break;
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		}
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	switch (aConfig.iParity)
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		{
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		case EParityNone: break;
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		case EParityEven: lcr|=K16550LCR_ParityEnable|K16550LCR_ParityEven; break;
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		case EParityOdd: lcr|=K16550LCR_ParityEnable; break;
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		case EParityMark: lcr|=K16550LCR_ParityEnable|K16550LCR_ParityMark; break;
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		case EParitySpace: lcr|=K16550LCR_ParityEnable|K16550LCR_ParitySpace; break;
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		}
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	iUart->SetLCR(lcr|K16550LCR_DLAB);
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	iUart->SetBaudRateDivisor(BaudRateDivisor[(TInt)aConfig.iRate]);
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	iUart->SetLCR(lcr);
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	iUart->SetFCR(K16550FCR_Enable|K16550FCR_RxReset|K16550FCR_TxReset|K16550FCR_RxTrig8);
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	}
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void DComm16550::Caps(TDes8 &aCaps) const
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//
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// return our caps
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//
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	{
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	Get16550CommsCaps(aCaps,iUnit);
sl@0
   418
	}
sl@0
   419
sl@0
   420
void DComm16550::Isr(TAny* aPtr)
sl@0
   421
//
sl@0
   422
// Service the UART interrupt
sl@0
   423
//
sl@0
   424
	{
sl@0
   425
	DComm16550& d=*(DComm16550*)aPtr;
sl@0
   426
	T16550Uart& u=*d.iUart;
sl@0
   427
	TUint rx[32];
sl@0
   428
	TUint xon=d.iLdd->iRxXonChar;
sl@0
   429
	TUint xoff=d.iLdd->iRxXoffChar;
sl@0
   430
sl@0
   431
	TUint isr=u.ISR();
sl@0
   432
	if (isr & K16550ISR_NotPending)
sl@0
   433
		return;
sl@0
   434
	isr&=K16550ISR_IntIdMask;
sl@0
   435
sl@0
   436
	// if receive data available or line status interrupt
sl@0
   437
	if (isr==K16550ISR_RDAI || isr==K16550ISR_RLSI)
sl@0
   438
		{
sl@0
   439
		TInt rxi=0;
sl@0
   440
		TInt x=0;
sl@0
   441
		while(u.TestLSR(K16550LSR_RxReady|K16550LSR_RxParityErr|K16550LSR_RxOverrun|K16550LSR_RxFrameErr|K16550LSR_RxBreak) && Kern::PowerGood())
sl@0
   442
			{
sl@0
   443
			TUint lsr=0;
sl@0
   444
			// checks for EIF flag
sl@0
   445
			if (isr==K16550ISR_RLSI)
sl@0
   446
				lsr=u.LSR()&(K16550LSR_RxParityErr|K16550LSR_RxOverrun|K16550LSR_RxFrameErr);
sl@0
   447
			TUint ch=u.RxData();
sl@0
   448
			// if error in this character
sl@0
   449
			if(lsr)
sl@0
   450
				{
sl@0
   451
				if (lsr & K16550LSR_RxParityErr)
sl@0
   452
					ch|=KReceiveIsrParityError;
sl@0
   453
				if (lsr & K16550LSR_RxBreak)
sl@0
   454
					ch|=KReceiveIsrBreakError;
sl@0
   455
				if (lsr & K16550LSR_RxFrameErr)
sl@0
   456
					ch|=KReceiveIsrFrameError;
sl@0
   457
				if (lsr & K16550LSR_RxOverrun)
sl@0
   458
					ch|=KReceiveIsrOverrunError;
sl@0
   459
				}
sl@0
   460
			if (ch==xon)
sl@0
   461
				x=1;
sl@0
   462
			else if (ch==xoff)
sl@0
   463
				x=-1;
sl@0
   464
			else
sl@0
   465
				rx[rxi++]=ch;
sl@0
   466
			}
sl@0
   467
		d.ReceiveIsr(rx,rxi,x);
sl@0
   468
		return;
sl@0
   469
		}
sl@0
   470
	// if TFS flag and TIE
sl@0
   471
	if (isr==K16550ISR_THREI)
sl@0
   472
		{
sl@0
   473
		TInt n;
sl@0
   474
		for (n=0; n<16; ++n)
sl@0
   475
			{
sl@0
   476
			TInt r=d.TransmitIsr();
sl@0
   477
			if(r<0)
sl@0
   478
				{
sl@0
   479
				//no more to send
sl@0
   480
				// Disable the TX interrupt
sl@0
   481
				u.ModifyIER(K16550IER_THREI,0);
sl@0
   482
				d.iTransmitting=EFalse;
sl@0
   483
				break;
sl@0
   484
				}
sl@0
   485
			u.SetTxData(r);
sl@0
   486
			}
sl@0
   487
		d.CheckTxBuffer();
sl@0
   488
		return;
sl@0
   489
		}
sl@0
   490
	// must be signal change
sl@0
   491
	d.StateIsr(d.Signals());
sl@0
   492
	}
sl@0
   493
sl@0
   494
sl@0
   495
const TInt KUart16550ThreadPriority = 27;
sl@0
   496
_LIT(KUar16550tDriverThread,"UART16550_Thread");
sl@0
   497
sl@0
   498
DECLARE_STANDARD_PDD()
sl@0
   499
	{
sl@0
   500
	return new DDriverComm;
sl@0
   501
	}
sl@0
   502