PortAccessNt4.c

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/*
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 *  Copyright 2004-2006 Spiro Trikaliotis
 *  Copyright 1998      Wolfgang Moser
 *
 *  This file is heavily based on LPTDTC by Wolfgang Moser.
 */

#include <initguid.h>
#include <wdm.h>
#include "cbm_driver.h"



// Set ExtendedTests to 1, if you want to try searching for unusual EPP's
// But take notice that the functionality of this test is not guaranteed!
#define AdvancedEPPTests 1

enum lptMode
{
        lptN_A  = 0,
        lptSPP  = 1,
        lptPS2  = 2,
        lptEPP  = 3,
        lptECP  = 4,
        lptEPPc = 5,                    // EPP with special control word to enable
};

enum ecpMode
{
        ecpNOECR   = 0,      // no ECP-Port found!!!

        ecpSTNDRD  = 1,
        ecpBYTE    = 2,
        ecpSTDFIFO = 3,
        ecpECPFIFO = 4,
        ecpEPP     = 5,
        ecpRESVRD  = 6,
        ecpFIFOTST = 7,
        ecpCONFIG  = 8
};

// set the Bidirectional-Flag to output (normal mode)
static void
BIDIoutp(PUCHAR port)
{
    WRITE_PORT_UCHAR(port+2,0xC4);
}

// set the Bidirectional-Flag to input (reverse mode)
static void
BIDIinp(PUCHAR port)
{
    WRITE_PORT_UCHAR(port+2,0xE4);
}

// clear the Timeout-Flag
static void
EPPclear(PUCHAR port)
{
    unsigned char val=READ_PORT_UCHAR(port+1);

                                          // Reset Timeout-Flag by reading
    WRITE_PORT_UCHAR(port+1,val|0x01);    // or by writing 0
    WRITE_PORT_UCHAR(port+1,val&0xFE);    // or by writing 1 to it
}

//----------------------------------------------------------------
// Port Detection Routines
//----------------------------------------------------------------

// ECP port detection
static enum lptMode
ECPdetect(PUCHAR port)
{
    enum lptMode ret = lptN_A;

    unsigned char ECR = READ_PORT_UCHAR(port+0x402)&~0x07;
    do
    {
        WRITE_PORT_UCHAR(port+0x402,0x34);
        WRITE_PORT_UCHAR(port+2,0xC6);
        if(READ_PORT_UCHAR(port+0x402)!=0x35){
        ECR=0xC4;                                                       // There's no ECR,
        break;
    }

    WRITE_PORT_UCHAR(port+0x402,0x35);
    WRITE_PORT_UCHAR(port+0x402,0xd4);
    READ_PORT_UCHAR(port+0x400);
    WRITE_PORT_UCHAR(port+0x400,0xAA);
    if(READ_PORT_UCHAR(port+0x400)!=0xAA)
        break;

    WRITE_PORT_UCHAR(port+0x400,0x55);
    if(READ_PORT_UCHAR(port+0x400)!=0x55)
        break;

    ret=lptECP;

    } while(0);

    WRITE_PORT_UCHAR(port+0x402,0x35);
    WRITE_PORT_UCHAR(port+0x402,ECR);
    return ret;
}

// EPP port detection without Control port initialisation
static enum lptMode
EPPdWOC(PUCHAR port)
{
    do
    {
        EPPclear(port);
        WRITE_PORT_UCHAR(port+3,0xAA);
        EPPclear(port);
        if(READ_PORT_UCHAR(port+3)!=0xAA)
            break;

        EPPclear(port);
        WRITE_PORT_UCHAR(port+3,0x55);
        EPPclear(port);

        if(READ_PORT_UCHAR(port+3)!=0x55)
            break;

        return lptEPP;

    } while(0);

    EPPclear(port);
    WRITE_PORT_UCHAR(port+3,0x00);
    READ_PORT_UCHAR(port+3);

    if(!(READ_PORT_UCHAR(port+1)&0x01))
        return lptN_A;

    EPPclear(port);
    if(READ_PORT_UCHAR(port+1)&0x01)
        return lptN_A;

    return lptEPP;
}

// set the Bidirectional-Flag to input (reverse mode) and block
// the DataStrobe, AddressStrobe and Write line manually, so
// that the EPP can't send any automatic handshake signal
static enum lptMode
EPPdetect(PUCHAR port)
{
    WRITE_PORT_UCHAR(port+2, (UCHAR) 0xEF);
    return EPPdWOC(port);
}

// Parallel Printer Port detection (SPP or PS/2)
static enum lptMode
PPPdetect(PUCHAR port)
{
    BIDIoutp(port);

    WRITE_PORT_UCHAR(port,0xAA);
    if(READ_PORT_UCHAR(port)!=0xAA)
        return lptN_A;

    WRITE_PORT_UCHAR(port,0x55);
    if(READ_PORT_UCHAR(port)!=0x55)
        return lptN_A;

    BIDIinp(port);

    WRITE_PORT_UCHAR(port,0xAA);
    if(READ_PORT_UCHAR(port)!=0xAA)
        return lptPS2;

    WRITE_PORT_UCHAR(port,0x55);
    if(READ_PORT_UCHAR(port)!=0x55)
        return lptPS2;

    return lptSPP;
}

// perform a parallel printer port reset
static void
ResetLPT(PUCHAR port)
{
    int i;

    // since a port read/write command is delayed by ISA bus waitstates to
    // 1,6 æs, we can use it for a simple system independent delay routine.

    // But it would be much better to program one of the system
    // timers to delay 16 micro seconds
    for(i=10;i>0;i--)
        WRITE_PORT_UCHAR(port+2,0xC0);

    BIDIoutp(port);
}

//----------------------------------------------------------------
// Port Mode Resolving Routines
//----------------------------------------------------------------

#if AdvancedEPPTests
enum lptMode AdvEPP(PUCHAR port){
    unsigned char EPPctrl=0;

    // check all control words to free up the EPP
    do
    {
        EPPctrl |= 0x04;        // don't do a reset
            // write the special Control word, for freeing up the EPP
        WRITE_PORT_UCHAR(port+2,EPPctrl);

        if (EPPdWOC(port)!=lptN_A)
            return lptEPPc;

        EPPctrl++;
    } while(EPPctrl);

    return lptN_A;
}

// Resolving the special Control-Word to enable an EPP
static char *
EPPcontrol(PUCHAR port){
    int ret;
    static char ctrlWord[8];
    unsigned int  done0[8], done1[8];
    unsigned char i,EPPctrl, OldCtrl,mask;

    for (i=0;i<8;i++)
        done0[i]=done1[i]=0;

    OldCtrl = READ_PORT_UCHAR(port+2)&0x1f;
    EPPctrl = 0;  // check all control words to free up the EPP

    do
    {
        EPPctrl|=0x04;  // don't do a reset
        // write the special Control word, for freeing up the EPP
        WRITE_PORT_UCHAR(port+2,EPPctrl);
        if(EPPdWOC(port)!=lptN_A)
        {
            // EPP is enabled with this control word
            // return EPPctrl;
            for(i=0,mask=0x80;i<8;i++,mask>>=1)
            {
                if(EPPctrl&mask)
                    done1[i]++;
                else 
                    done0[i]++;
            }
        }
        EPPctrl++;
    } while(EPPctrl);

    WRITE_PORT_UCHAR(port+2,OldCtrl);

    for (i=0;i<8;i++)
    {
        if(done0[i]==done1[i])
        {
            if(!done0[i])        ctrlWord[i]='!';       // Control-Word could not found
            else                                 ctrlWord[i]='X';       // This Bit cares nobody
        }
        else if(!done0[i]) ctrlWord[i]='1'; // This Bit must be 1
        else if(!done1[i]) ctrlWord[i]='0';     // This Bit must be 0
        else               ctrlWord[i]='?';     // This Bit depends on other Bits
    }
    return ctrlWord;
}
#else
static char *
EPPcontrol(PUCHAR)
{
    return "XX0X0100";
}
#endif

static enum lptMode
LPTmode(PUCHAR port)
{
    enum lptMode ret=lptN_A;

    // check for valid portaddresses (LPT 1-6)
    // valid port addresses only at 0x200, 0x204, 0x208, ..., 0x3fc

    if((((ULONG_PTR)port) & ~0x1fc)!=0x200)
        return lptN_A;

        //      if(!(port&0x07)){
        // test for ECP/EPP only at 0/8-bases

    ResetLPT(port);
    //  ECP test doesn't touch any data registers, so no reset is needed

    do
    {
        // tests for an ECP
        if((ret = ECPdetect(port)) != lptN_A)
            break;

        // perform a reset to prevent printers from printing unusable stuff
        ResetLPT(port);

        // tests for an EPP
        if ((ret = EPPdetect(port)) != lptN_A)
            break;

#if AdvancedEPPTests
        // tests for an EPP with different control words
        if ((ret = AdvEPP(port)) != lptN_A)
            break;
#endif
        // tests for a SPP or PS/2
        if ((ret = PPPdetect(port)) != lptN_A)
            break;

    } while(0);
    BIDIoutp(port);
    return ret;
}

static enum ecpMode
ECPmode(PUCHAR port)
{
    if (LPTmode(port) != lptECP)
        return ecpNOECR;

    return (enum ecpMode)(ecpSTNDRD + (READ_PORT_UCHAR(port+0x402)>>5));
}

static enum ecpMode
SetECPmode(PUCHAR port, enum ecpMode mode)
{
    unsigned char oldvalue;

    if (LPTmode(port) != lptECP)
        return ecpNOECR;

    oldvalue = READ_PORT_UCHAR(port+0x402);

    WRITE_PORT_UCHAR(port+0x402, (oldvalue & 0x3f) | ((mode - ecpSTNDRD) << 5));

    return (enum ecpMode)(ecpSTNDRD + (oldvalue>>5));
}

//----------------------------------------------------------------
// Some helper functions
//----------------------------------------------------------------

static int
preprprt(PUCHAR port)
{
    enum lptMode mode;
    const char *modes[6]={"N/A","SPP","PS/2","EPP","ECP","EPPc"};

    FUNC_ENTER();

    mode=LPTmode(port);
    DBG_PRINT((DBG_PREFIX "at 0x%03X, %s", port, modes[mode]));

    FUNC_LEAVE_INT(mode);
}

static int
prport(PUCHAR port)
{
    const char *ecpM[9]={
        "no ECR found",
        "Standard Mode",
        "Byte Mode",
        "Parallel Port FIFO Mode",
        "ECP FIFO Mode",
        "EPP Mode",
        "Reserved",
        "FIFO Test Mode",
        "Configuration Mode"
    };

    int ret;

    FUNC_ENTER();

    ret=1;

    switch (preprprt(port))
    {
        case lptN_A:
            ret=0;
            break;
        case lptEPPc:
            DBG_PRINT((DBG_PREFIX ",  EPP-Enable-Timeout-Bit-Detection-Control-Word:"
                " %s", EPPcontrol(port)));
            break;

        case lptECP:
            DBG_PRINT((DBG_PREFIX ",  ECP-Mode: %s", ecpM[ECPmode(port)]));
    }
    DBG_PRINT((DBG_PREFIX ""));

    FUNC_LEAVE_INT(ret);
}


NTSTATUS
ParPortSetModeNt4(PDEVICE_EXTENSION Pdx)
{
    NTSTATUS ntStatus = STATUS_SUCCESS;
    enum lptMode lptmode = Pdx->HandleEcpEppMyself & 0xFF;
    enum ecpMode oldecpmode = ecpNOECR;

    FUNC_ENTER();

    if (lptmode == lptN_A)
    {
        DBG_PRINT((DBG_PREFIX "Trying to find out mode of 0x%04x", Pdx->ParPortPortAddress));
        lptmode = LPTmode(Pdx->ParPortPortAddress);
        prport(Pdx->ParPortPortAddress);
    }

    if (lptmode == lptECP)
    {
        oldecpmode = ECPmode(Pdx->ParPortPortAddress);

        DBG_PRINT((DBG_PREFIX "Setting ECP mode to BYTE mode"));
        SetECPmode(Pdx->ParPortPortAddress, ecpBYTE);

        DBG_PRINT((DBG_PREFIX "Checking if mode has changed:"));
        prport(Pdx->ParPortPortAddress);
    }

    if (lptmode > lptSPP)
    {
        DBG_PRINT((DBG_PREFIX "Writing the value 0xE4 to 0x%04x", Pdx->ParPortPortAddress+2));
        WRITE_PORT_UCHAR(Pdx->ParPortPortAddress+2,0xE4);
    }

    Pdx->HandleEcpEppMyself = (lptmode & 0xFF) | ((oldecpmode & 0xFF) << 8);

    FUNC_LEAVE_NTSTATUS(ntStatus);
}

NTSTATUS
ParPortUnsetModeNt4(PDEVICE_EXTENSION Pdx)
{
    NTSTATUS ntStatus = STATUS_SUCCESS;
    enum lptMode lptmode = Pdx->HandleEcpEppMyself & 0xFF;
    enum ecpMode oldecpmode = (Pdx->HandleEcpEppMyself & 0xFF00) >> 8;

    FUNC_ENTER();

    if (lptmode == lptECP)
    {
        DBG_PRINT((DBG_PREFIX "Setting ECP mode back to standard mode"));
        SetECPmode(Pdx->ParPortPortAddress, oldecpmode);

        DBG_PRINT((DBG_PREFIX "Checking if mode has changed:"));
        prport(Pdx->ParPortPortAddress);
    }

    FUNC_LEAVE_NTSTATUS(ntStatus);
}

extern VOID
cbmiec_udelay(IN ULONG howlong); // howlong in ms!

NTSTATUS
ParPortSetMode(PDEVICE_EXTENSION Pdx)
{
    NTSTATUS ntStatus = STATUS_LOGON_FAILURE; // this is just a dummy failure value to allow falling into NT4 processing

    FUNC_ENTER();

    if (!Pdx->HandleEcpEppMyself)
    {
        // First, try to set the mode via WDM functions.
        // Remember: Even if we install the NT4 driver, we might be running on 2000 or up.
        ntStatus = ParPortSetModeWdm(Pdx);
    }

    if (Pdx->HandleEcpEppMyself || ((ntStatus == STATUS_INVALID_PARAMETER) && Pdx->IsNT4))
    {
        ntStatus = ParPortSetModeNt4(Pdx);
        cbmiec_udelay(1000 * 10);
    }

    FUNC_LEAVE_NTSTATUS(ntStatus);
}

NTSTATUS
ParPortUnsetMode(PDEVICE_EXTENSION Pdx)
{
    NTSTATUS ntStatus;

    FUNC_ENTER();

    if (Pdx->HandleEcpEppMyself == 0)
    {
        ntStatus = ParPortUnsetModeWdm(Pdx);
    }
    else
    {
        ntStatus = ParPortUnsetModeNt4(Pdx);
    }

    FUNC_LEAVE_NTSTATUS(ntStatus);
}

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