windows-xp/Source/XPSP1/NT/drivers/net/irda/mknet/sys/sir.c

/*****************************************************************************
 **																			**
 **	COPYRIGHT (C) 2000, 2001 MKNET CORPORATION								**
 **	DEVELOPED FOR THE MK7100-BASED VFIR PCI CONTROLLER.						**
 **																			**
 *****************************************************************************/

 /**********************************************************************

Module Name:
	SIR.C

Routines:
	NdisToSirPacket
	ComputeSirFCS
	ProcRXSir

Comments:

**********************************************************************/


#include	"precomp.h"
#include	"protot.h"
#pragma		hdrstop



// SIR only
const USHORT fcsTable[256] =
{
        0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
        0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
        0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
        0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
        0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
        0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
        0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
        0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
        0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
        0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
        0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
        0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
        0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
        0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
        0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
        0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
        0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
        0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
        0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
        0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
        0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
        0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
        0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
        0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
        0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
        0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
        0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
        0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
        0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
        0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
        0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
        0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};





ULONG __inline EscapeSlowIrData(PUCHAR Dest, UCHAR SourceByte)
{
    switch (SourceByte){
        case SIR_BOF:
        case SIR_EOF:
        case SIR_ESC:
            Dest[0] = SIR_ESC;
            Dest[1] = SourceByte ^ SIR_ESC_COMP;
            return 2;

        default:
            Dest[0] = SourceByte;
            return 1;
    }
}




//-----------------------------------------------------------------------------
// Procedure:	[NdisToSirPacket]
//-----------------------------------------------------------------------------
BOOLEAN NdisToSirPacket	(PMK7_ADAPTER Adapter,
						PNDIS_PACKET Packet,
						UCHAR *irPacketBuf,
						UINT irPacketBufLen,
						UINT *irPacketLen
					)
{
	PNDIS_BUFFER    CurrentBuffer, NextBuffer;
	UINT			CurrentLength;
	PVOID           VirtualAddress;
	PNDIS_BUFFER ndisBuf;
	UINT i, ndisPacketBytes = 0, I_fieldBytes, totalBytes = 0;
	UINT ndisPacketLen, numExtraBOFs;
	SIR_FCS_TYPE fcs;
	UCHAR nextChar;
    UCHAR *bufData;
    UINT bufLen;
	PNDIS_IRDA_PACKET_INFO packetInfo = GetPacketInfo(Packet);


	// Get the packet's entire length and its first NDIS buffer
	NdisQueryPacket(Packet, NULL, NULL, &ndisBuf, &ndisPacketLen);

	// Make sure that the packet is big enough to be legal.
	// It consists of an A, C, and variable-length I field.
	if (ndisPacketLen < ADDR_SIZE + CONTROL_SIZE){
//		DBGERR(("packet too short in NdisToIrPacket (%d bytes)", ndisPacketLen));
		return (FALSE);
	}
	else {
		I_fieldBytes = ndisPacketLen - ADDR_SIZE - CONTROL_SIZE;
	}


	// Make sure that we won't overwrite our contiguous buffer.
	// Make sure that the passed-in buffer can accomodate this packet's
	// data no matter how much it grows through adding ESC-sequences, etc.
	if (ndisPacketLen > MK7_MAXIMUM_PACKET_SIZE) {
		// The packet is too large
		// Tell the caller to retry with a packet size large
		// enough to get past this stage next time.
		//DBGERR(("Packet too large in NdisToIrPacket (%d=%xh bytes), MAX_IRDA_DATA_SIZE=%d, irPacketBufLen=%d.",  ndisPacketLen, ndisPacketLen, MAX_IRDA_DATA_SIZE, irPacketBufLen));
		*irPacketLen = ndisPacketLen;
		return (FALSE);
	}
	
    if (!ndisBuf) {
        // DBGERR(("No NDIS_BUFFER in NdisToIrPacket"));
        return (FALSE);
    }
	
	
	CurrentBuffer = ndisBuf;
	while (CurrentBuffer != NULL) {
			NdisQueryBufferSafe(CurrentBuffer, &VirtualAddress, &CurrentLength, 16);
			if (!VirtualAddress) {
#if DBG
				DbgPrint("==> Throw Away Failed Packet\n\r");
#endif
				return (FALSE);
			}
			NdisGetNextBuffer(CurrentBuffer, &NextBuffer);
			CurrentBuffer = NextBuffer;
	}

	// NDIS requirement
//  NdisQueryBuffer(ndisBuf, (PVOID *)&bufData, &bufLen);
    NdisQueryBufferSafe(ndisBuf, (PVOID *)&bufData, &bufLen,16);

	/*
	 *  Now begin building the IR frame.
	 *
	 *  This is the final format:
	 *
	 *      extra BOFs ...
	 *		BOF	(1)
	 *		NdisMediumIrda packet (what we get from NDIS):
	 *			Address (1)
	 *			Control (1)
	 *		FCS	(2)
	 *      EOF (1)
	 */

    // Prepend BOFs (extra BOFs + 1 actual BOF)
	// 4.1.0
	if ((Adapter->HwVersion==HW_VER_1) && (Adapter->CurrentSpeed <= MAX_SIR_SPEED))
		numExtraBOFs = HW_VER_1_EBOFS;	
	else
		numExtraBOFs = packetInfo->ExtraBOFs;

	
	if (numExtraBOFs > MAX_EXTRA_SIR_BOFS) {
		numExtraBOFs = MAX_EXTRA_SIR_BOFS;
	}
	for (i = totalBytes = 0; i < numExtraBOFs; i++) {
		*(SIR_BOF_TYPE *)(irPacketBuf+totalBytes) = SIR_EXTRA_BOF;
		totalBytes += SIR_EXTRA_BOF_SIZE;
	}
	*(SIR_BOF_TYPE *)(irPacketBuf+totalBytes) = SIR_BOF;
	totalBytes += SIR_BOF_SIZE;

    fcs = 0xffff;

	// Fill TX buff w/ I data & calculate FCS as we go
    for (i=0; i<ndisPacketLen; i++) {

        ASSERT(bufData);
        nextChar = *bufData++;
        fcs = (fcs >> 8) ^ fcsTable[(fcs ^ nextChar) & 0xff];

		totalBytes += EscapeSlowIrData(&irPacketBuf[totalBytes], nextChar);
		
        if (--bufLen==0) {
            NdisGetNextBuffer(ndisBuf, &ndisBuf);
            if (ndisBuf) {
				// NDIS requriement
//				NdisQueryBuffer(ndisBuf, (PVOID *)&bufData, &bufLen);
				NdisQueryBufferSafe(ndisBuf, (PVOID *)&bufData, &bufLen,16);
            }
            else {
                bufData = NULL;
            }
        }
    }


    if (bufData != NULL) {
		// Packet was corrupt -- it misreported its size.
		// DBGERR(("Packet corrupt in NdisToIrPacket (buffer lengths don't add up to packet length)."));
		*irPacketLen = 0;
		return (FALSE);
    }

    fcs = ~fcs;

	// Put in the 16-bit FCS
    totalBytes += EscapeSlowIrData(&irPacketBuf[totalBytes], (UCHAR)(fcs&0xff));
    totalBytes += EscapeSlowIrData(&irPacketBuf[totalBytes], (UCHAR)(fcs>>8));

    // EOF
	*(SIR_EOF_TYPE *)&irPacketBuf[totalBytes] = SIR_EOF;
	totalBytes += SIR_EOF_SIZE;

	*irPacketLen = totalBytes;

//	DBGOUT(("... NdisToIrPacket converted %d-byte ndis pkt to %d-byte irda pkt:", ndisPacketLen, *irPacketLen));

	return (TRUE);
}



//----------------------------------------------------------------------
// Procedure:	[ComputeSirFCS]
//
//----------------------------------------------------------------------
USHORT ComputeSirFCS(UCHAR *data, UINT dataLen)
{
  USHORT fcs = 0xffff;
  UINT i;
 	
//  DBGOUT(("ComputeSirFCS() on %d-byte buffer.", dataLen));

  for (i = 0; i < dataLen; i++){
    fcs = (fcs >> 8) ^ fcsTable[(fcs ^ *data++) & 0xff];
  }

  fcs = ~fcs;

//  DBGOUT(("ComputeFCS returning %d=0x%x.", (UINT)fcs, (UINT)fcs));

  return (fcs);
}


//-----------------------------------------------------------------------------
// Procedure:   [ProcRXSir]
//
//-----------------------------------------------------------------------------
BOOLEAN	ProcRXSir(UCHAR *dBuff, UINT dCnt)
{
	USHORT fcs;


	// FCS is not computed over the FCS field. Need to look into this.
	// (It seems when the original FCS is included in the calculation,
	// we should get GOOD_FCS for result.)

	fcs = ComputeSirFCS(dBuff, dCnt);

	if (fcs != GOOD_FCS)
		return (FALSE);

	return (TRUE);
}