xref: /xsrc/external/mit/xf86-input-mouse/dist/src/pnp.c

/*
 * Copyright 1998 by Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Kazutaka YOKOTA not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Kazutaka YOKOTA makes no representations
 * about the suitability of this software for any purpose.  It is provided
 * "as is" without express or implied warranty.
 *
 * KAZUTAKA YOKOTA DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL KAZUTAKA YOKOTA BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <xorg-server.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <X11/X.h>
#include <X11/Xproto.h>
#include "inputstr.h"
#include "scrnintstr.h"
#include "xf86.h"
#include "xf86Priv.h"
#include "xf86Xinput.h"
#include "xf86_OSproc.h"
#include "mouse.h"
#include "mousePriv.h"

#ifdef MOUSEINITDEBUG
# define DEBUG
# define EXTMOUSEDEBUG
#endif

/* serial PnP ID string */
typedef struct {
    int revision;       /* PnP revision, 100 for 1.00 */
    char *eisaid;       /* EISA ID including mfr ID and product ID */
    char *serial;       /* serial No, optional */
    char *class;        /* device class, optional */
    char *compat;       /* list of compatible drivers, optional */
    char *description;  /* product description, optional */
    int neisaid;        /* length of the above fields... */
    int nserial;
    int nclass;
    int ncompat;
    int ndescription;
} pnpid_t;

/* symbol table entry */
typedef struct {
    const char *name;
    MouseProtocolID val;
} symtab_t;

/* PnP EISA/product IDs */
static symtab_t pnpprod[] = {
    { "KML0001",  PROT_THINKING },      /* Kensington ThinkingMouse */
    { "MSH0001",  PROT_IMSERIAL },      /* MS IntelliMouse */
    { "MSH0004",  PROT_IMSERIAL },      /* MS IntelliMouse TrackBall */
    { "KYEEZ00",  PROT_MS },            /* Genius EZScroll */
    { "KYE0001",  PROT_MS },            /* Genius PnP Mouse */
    { "KYE0002",  PROT_MS },            /* MouseSystem (Genius?) SmartScroll */
    { "KYE0003",  PROT_IMSERIAL },      /* Genius NetMouse */
    { "KYE0004",  PROT_IMSERIAL },      /* Genius NetScroll+ (serial) */
    { "LGI800C",  PROT_IMSERIAL },      /* Logitech MouseMan (4 button model) */
    { "LGI8033",  PROT_IMSERIAL },      /* Logitech Cordless MouseMan Wheel */
    { "LGI8050",  PROT_IMSERIAL },      /* Logitech MouseMan+ */
    { "LGI8051",  PROT_IMSERIAL },      /* Logitech FirstMouse+ */
    { "LGI8001",  PROT_LOGIMAN },       /* Logitech serial */
    { "A4W0005",  PROT_IMSERIAL },      /* A4 Tech 4D/4D+ Mouse */
    { "PEC9802",  PROT_IMSERIAL },      /* 8D Scroll Mouse */

    { "PNP0F00",  PROT_BM },            /* MS bus */
    { "PNP0F01",  PROT_MS },            /* MS serial */
    { "PNP0F02",  PROT_BM },            /* MS InPort */
    { "PNP0F03",  PROT_PS2 },           /* MS PS/2 */
    /*
     * EzScroll returns PNP0F04 in the compatible device field; but it
     * doesn't look compatible... XXX
     */
    { "PNP0F04",  PROT_MSC },           /* MouseSystems */
    { "PNP0F05",  PROT_MSC },           /* MouseSystems */
#ifdef notyet
    { "PNP0F06",  PROT_??? },           /* Genius Mouse */
    { "PNP0F07",  PROT_??? },           /* Genius Mouse */
#endif
    { "PNP0F08",  PROT_LOGIMAN },       /* Logitech serial */
    { "PNP0F09",  PROT_MS },            /* MS BallPoint serial */
    { "PNP0F0A",  PROT_MS },            /* MS PnP serial */
    { "PNP0F0B",  PROT_MS },            /* MS PnP BallPoint serial */
    { "PNP0F0C",  PROT_MS },            /* MS serial compatible */
    { "PNP0F0D",  PROT_BM },            /* MS InPort compatible */
    { "PNP0F0E",  PROT_PS2 },           /* MS PS/2 compatible */
    { "PNP0F0F",  PROT_MS },            /* MS BallPoint compatible */
#ifdef notyet
    { "PNP0F10",  PROT_??? },           /* TI QuickPort */
#endif
    { "PNP0F11",  PROT_BM },            /* MS bus compatible */
    { "PNP0F12",  PROT_PS2 },           /* Logitech PS/2 */
    { "PNP0F13",  PROT_PS2 },           /* PS/2 */
#ifdef notyet
    { "PNP0F14",  PROT_??? },           /* MS Kids Mouse */
#endif
    { "PNP0F15",  PROT_BM },            /* Logitech bus */
#ifdef notyet
    { "PNP0F16",  PROT_??? },           /* Logitech SWIFT */
#endif
    { "PNP0F17",  PROT_LOGIMAN },       /* Logitech serial compat */
    { "PNP0F18",  PROT_BM },            /* Logitech bus compatible */
    { "PNP0F19",  PROT_PS2 },           /* Logitech PS/2 compatible */
#ifdef notyet
    { "PNP0F1A",  PROT_??? },           /* Logitech SWIFT compatible */
    { "PNP0F1B",  PROT_??? },           /* HP Omnibook */
    { "PNP0F1C",  PROT_??? },           /* Compaq LTE TrackBall PS/2 */
    { "PNP0F1D",  PROT_??? },           /* Compaq LTE TrackBall serial */
    { "PNP0F1E",  PROT_??? },           /* MS Kids Trackball */
#endif
    { NULL,       PROT_UNKNOWN },
};

static const char *pnpSerial[] = {
        "BaudRate",     "1200",
        "DataBits",     "7",
        "StopBits",     "1",
        "Parity",       "None",
        "FlowControl",  "None",
        "VTime",        "0",
        "VMin",         "1",
        NULL
};

static int pnpgets(InputInfoPtr, char *, Bool *prePNP);
static int pnpparse(InputInfoPtr, pnpid_t *, char *, int);
static MouseProtocolID prepnpparse(InputInfoPtr pInfo, char *buf);
static symtab_t *pnpproto(pnpid_t *);
static symtab_t *gettoken(symtab_t *, char *, int);
static MouseProtocolID getPs2ProtocolPnP(InputInfoPtr pInfo);
static MouseProtocolID probePs2ProtocolPnP(InputInfoPtr pInfo);

static MouseProtocolID
MouseGetSerialPnpProtocol(InputInfoPtr pInfo)
{
    char buf[256];      /* PnP ID string may be up to 256 bytes long */
    pnpid_t pnpid;
    symtab_t *t;
    int len;
    Bool prePNP;

    if ((len = pnpgets(pInfo, buf, &prePNP)) > 0)
    {
        if (!prePNP) {
            if (pnpparse(pInfo, &pnpid, buf, len) &&
                (t = pnpproto(&pnpid)) != NULL) {
                xf86MsgVerb(X_INFO, 2, "%s: PnP-detected protocol ID: %d\n",
                            pInfo->name, t->val);
                return (t->val);
            }
        } else
            return prepnpparse(pInfo,buf);
    }
    return PROT_UNKNOWN;
}

MouseProtocolID
MouseGetPnpProtocol(InputInfoPtr pInfo)
{
    MouseDevPtr  pMse = pInfo->private;
    mousePrivPtr mPriv = (mousePrivPtr)pMse->mousePriv;
    MouseProtocolID val;
    CARD32 last;

    if ((val = MouseGetSerialPnpProtocol(pInfo)) != PROT_UNKNOWN) {
        if (val == MouseGetSerialPnpProtocol(pInfo))
            return val;
    }

    last = mPriv->pnpLast;
    mPriv->pnpLast = currentTime.milliseconds;

    if (last) {
        if (last - currentTime.milliseconds < 100
            || (mPriv->disablePnPauto
                && (last - currentTime.milliseconds < 10000))) {
#ifdef EXTMOUSEDEBUG
            xf86ErrorF("Mouse: Disabling PnP\n");
#endif
            mPriv->disablePnPauto = TRUE;
            return PROT_UNKNOWN;
        }
    }

#ifdef EXTMOUSEDEBUG
    if (mPriv->disablePnPauto)
        xf86ErrorF("Mouse: Enabling PnP\n");
#endif
    mPriv->disablePnPauto = FALSE;

    if (mPriv->soft)
        return getPs2ProtocolPnP(pInfo);
    else
        return probePs2ProtocolPnP(pInfo);
}

/*
 * Try to elicit a PnP ID as described in
 * Microsoft, Hayes: "Plug and Play External COM Device Specification,
 * rev 1.00", 1995.
 *
 * The routine does not fully implement the COM Enumerator as per Section
 * 2.1 of the document.  In particular, we don't have idle state in which
 * the driver software monitors the com port for dynamic connection or
 * removal of a device at the port, because `moused' simply quits if no
 * device is found.
 *
 * In addition, as PnP COM device enumeration procedure slightly has
 * changed since its first publication, devices which follow earlier
 * revisions of the above spec. may fail to respond if the rev 1.0
 * procedure is used. XXX
 */
static int
pnpgets(InputInfoPtr pInfo, char *buf, Bool *prePNP)
{
    int i;
    char c;
    pointer pnpOpts;

#if 0
    /*
     * This is the procedure described in rev 1.0 of PnP COM device spec.
     * Unfortunately, some devices which conform to earlier revisions of
     * the spec gets confused and do not return the ID string...
     */

    /* port initialization (2.1.2) */
    if ((i = xf86GetSerialModemState(pInfo->fd)) == -1)
        return 0;
    i |= XF86_M_DTR;            /* DTR = 1 */
    i &= ~XF86_M_RTS;           /* RTS = 0 */
    if (xf86SetSerialModemState(pInfo->fd, i) == -1)
        goto disconnect_idle;
    usleep(200000);
    if ((i = xf86GetSerialModemState(pInfo->fd)) == -1 ||
        (i & XF86_M_DSR) == 0)
        goto disconnect_idle;

    /* port setup, 1st phase (2.1.3) */
    pnpOpts = xf86OptionListCreate(pnpSerial, -1, 1);
    xf86SetSerial(pInfo->fd, pnpOpts);
    i = TIOCM_DTR | TIOCM_RTS;  /* DTR = 0, RTS = 0 */
    xf86SerialModemClearBits(pInfo->fd, i);
    usleep(200000);
    i = TIOCM_DTR;              /* DTR = 1, RTS = 0 */
    xf86SerialModemSetBits(pInfo->fd, i);
    usleep(200000);

    /* wait for response, 1st phase (2.1.4) */
    xf86FlushInput(pInfo->fd);
    i = TIOCM_RTS;              /* DTR = 1, RTS = 1 */
    xf86SerialModemSetBits(pInfo->fd, i);

    /* try to read something */
    if (xf86WaitForInput(pInfo->fd, 200000) <= 0) {

        /* port setup, 2nd phase (2.1.5) */
        i = TIOCM_DTR | TIOCM_RTS;      /* DTR = 0, RTS = 0 */
        xf86SerialModemClearBits(pInfo->fd, i);
        usleep(200000);

        /* wait for response, 2nd phase (2.1.6) */
        xf86FlushInput(pInfo->fd);
        i = TIOCM_DTR | TIOCM_RTS;      /* DTR = 1, RTS = 1 */
        xf86SerialModemSetBits(pInfo->fd, i);

        /* try to read something */
        if (xf86WaitForInput(pInfo->fd, 200000) <= 0)
            goto connect_idle;
    }
#else
    /*
     * This is a simplified procedure; it simply toggles RTS.
     */

    if ((i = xf86GetSerialModemState(pInfo->fd)) == -1)
        return 0;
    i |= XF86_M_DTR;            /* DTR = 1 */
    i &= ~XF86_M_RTS;           /* RTS = 0 */
    if (xf86SetSerialModemState(pInfo->fd, i) == -1)
        goto disconnect_idle;
    usleep(200000);

    pnpOpts = xf86OptionListCreate(pnpSerial, -1, 1);
    xf86SetSerial(pInfo->fd, pnpOpts);

    /* wait for response */
    xf86FlushInput(pInfo->fd);
    i = XF86_M_DTR | XF86_M_RTS;        /* DTR = 1, RTS = 1 */
    xf86SerialModemSetBits(pInfo->fd, i);

    /* try to read something */
    if (xf86WaitForInput(pInfo->fd, 200000) <= 0)
        goto connect_idle;
#endif

    /* collect PnP COM device ID (2.1.7) */
    i = 0;
    *prePNP = FALSE;

    usleep(200000);     /* the mouse must send `Begin ID' within 200msec */
    while (xf86ReadSerial(pInfo->fd, &c, 1) == 1) {
        /* we may see "M", or "M3..." before `Begin ID' */
        if (c == 'M')
            *prePNP = TRUE;

        if ((c == 0x08) || (c == 0x28)) {       /* Begin ID */
            *prePNP = FALSE;
            buf[0] = c;
            i = 1;
            break;
        }
        if (*prePNP)
            buf[i++] = c;

        if (xf86WaitForInput(pInfo->fd, 200000) <= 0)
            break;
    }
    if (i <= 0) {
        /* we haven't seen `Begin ID' in time... */
        goto connect_idle;
    }
    if (*prePNP)
        return i;

    ++c;                        /* make it `End ID' */
    for (;;) {
        if (xf86WaitForInput(pInfo->fd, 200000) <= 0)
            break;

        xf86ReadSerial(pInfo->fd, &buf[i], 1);
        if (buf[i++] == c)      /* End ID */
            break;
        if (i >= 256)
            break;
    }
    if (buf[i - 1] != c)
        goto connect_idle;
    return i;

    /*
     * According to PnP spec, we should set DTR = 1 and RTS = 0 while
     * in idle state.  But, `moused' shall set DTR = RTS = 1 and proceed,
     * assuming there is something at the port even if it didn't
     * respond to the PnP enumeration procedure.
     */
disconnect_idle:
    i = XF86_M_DTR | XF86_M_RTS;                /* DTR = 1, RTS = 1 */
    xf86SerialModemSetBits(pInfo->fd, i);
connect_idle:
    return 0;
}

static int
pnpparse(InputInfoPtr pInfo, pnpid_t *id, char *buf, int len)
{
    char s[3];
    int offset;
    int sum = 0;
    int i, j;

    id->revision = 0;
    id->eisaid = NULL;
    id->serial = NULL;
    id->class = NULL;
    id->compat = NULL;
    id->description = NULL;
    id->neisaid = 0;
    id->nserial = 0;
    id->nclass = 0;
    id->ncompat = 0;
    id->ndescription = 0;

    offset = 0x28 - buf[0];

    /* calculate checksum */
    for (i = 0; i < len - 3; ++i) {
        sum += buf[i];
        buf[i] += offset;
    }
    sum += buf[len - 1];
    for (; i < len; ++i)
        buf[i] += offset;
    xf86MsgVerb(X_INFO, 2, "%s: PnP ID string: `%*.*s'\n", pInfo->name,
                len, len, buf);

    /* revision */
    buf[1] -= offset;
    buf[2] -= offset;
    id->revision = ((buf[1] & 0x3f) << 6) | (buf[2] & 0x3f);
    xf86MsgVerb(X_INFO, 2, "%s: PnP rev %d.%02d\n", pInfo->name,
                id->revision / 100, id->revision % 100);

    /* EISA vendor and product ID */
    id->eisaid = &buf[3];
    id->neisaid = 7;

    /* option strings */
    i = 10;
    if (buf[i] == '\\') {
        /* device serial # */
        for (j = ++i; i < len; ++i) {
            if (buf[i] == '\\')
                break;
        }
        if (i >= len)
            i -= 3;
        if (i - j == 8) {
            id->serial = &buf[j];
            id->nserial = 8;
        }
    }
    if (buf[i] == '\\') {
        /* PnP class */
        for (j = ++i; i < len; ++i) {
            if (buf[i] == '\\')
                break;
        }
        if (i >= len)
            i -= 3;
        if (i > j + 1) {
            id->class = &buf[j];
            id->nclass = i - j;
        }
    }
    if (buf[i] == '\\') {
        /* compatible driver */
        for (j = ++i; i < len; ++i) {
            if (buf[i] == '\\')
                break;
        }
        /*
         * PnP COM spec prior to v0.96 allowed '*' in this field,
         * it's not allowed now; just ignore it.
         */
        if (buf[j] == '*')
            ++j;
        if (i >= len)
            i -= 3;
        if (i > j + 1) {
            id->compat = &buf[j];
            id->ncompat = i - j;
        }
    }
    if (buf[i] == '\\') {
        /* product description */
        for (j = ++i; i < len; ++i) {
            if (buf[i] == ';')
                break;
        }
        if (i >= len)
            i -= 3;
        if (i > j + 1) {
            id->description = &buf[j];
            id->ndescription = i - j;
        }
    }

    /* checksum exists if there are any optional fields */
    if ((id->nserial > 0) || (id->nclass > 0)
        || (id->ncompat > 0) || (id->ndescription > 0)) {
        xf86MsgVerb(X_INFO, 4, "%s: PnP checksum: 0x%02X\n", pInfo->name, sum);
        sprintf(s, "%02X", sum & 0x0ff);
        if (strncmp(s, &buf[len - 3], 2) != 0) {
#if 0
            /*
             * Checksum error!!
             * I found some mice do not comply with the PnP COM device
             * spec regarding checksum... XXX
             */
            return FALSE;
#endif
        }
    }

    return TRUE;
}

/* We can only identify MS at the moment */
static MouseProtocolID
prepnpparse(InputInfoPtr pInfo, char *buf)
{
    if (buf[0] == 'M' && buf[1] == '3')
        return PROT_MS;
    return PROT_UNKNOWN;
}


static symtab_t *
pnpproto(pnpid_t *id)
{
    symtab_t *t;
    int i, j;

    if (id->nclass > 0)
        if (strncmp(id->class, "MOUSE", id->nclass) != 0)
            /* this is not a mouse! */
            return NULL;

    if (id->neisaid > 0) {
        t = gettoken(pnpprod, id->eisaid, id->neisaid);
        if (t->val != -1)
            return t;
    }

    /*
     * The 'Compatible drivers' field may contain more than one
     * ID separated by ','.
     */
    if (id->ncompat <= 0)
        return NULL;
    for (i = 0; i < id->ncompat; ++i) {
        for (j = i; id->compat[i] != ','; ++i)
            if (i >= id->ncompat)
                break;
        if (i > j) {
            t = gettoken(pnpprod, id->compat + j, i - j);
            if (t->val != -1)
                return t;
        }
    }

    return NULL;
}

/* name/val mapping */

static symtab_t *
gettoken(symtab_t *tab, char *s, int len)
{
    int i;

    for (i = 0; tab[i].name != NULL; ++i) {
        if (strncmp(tab[i].name, s, len) == 0)
            break;
    }
    return &tab[i];
}

/******************* PS/2 PnP probing ****************/

static int
readMouse(InputInfoPtr pInfo, unsigned char *u)
{

    if (xf86WaitForInput(pInfo->fd, 200000) <= 0)
        return FALSE;

    xf86ReadSerial(pInfo->fd, u, 1);
    return TRUE;
}

static void
ps2DisableWrapMode(InputInfoPtr pInfo)
{
    unsigned char reset_wrap_mode[] = { 0xEC };
    ps2SendPacket(pInfo, reset_wrap_mode, sizeof(reset_wrap_mode));
}

Bool
ps2SendPacket(InputInfoPtr pInfo, unsigned char *bytes, int len)
{
    unsigned char c;
    int i,j;

#ifdef DEBUG
    xf86ErrorF("Ps/2 data package:");
    for (i = 0; i < len; i++)
        xf86ErrorF(" %x", *(bytes + i));
    xf86ErrorF("\n");
#endif

    for (i = 0; i < len; i++) {
        for (j = 0; j < 10; j++) {
            xf86WriteSerial(pInfo->fd, bytes + i, 1);
            usleep(10000);
            if (!readMouse(pInfo,&c)) {
#ifdef DEBUG
                xf86ErrorF("sending 0x%x to PS/2 unsuccessful\n",*(bytes + i));
#endif
                return FALSE;
            }
#ifdef DEBUG
            xf86ErrorF("Received: 0x%x\n",c);
#endif
            if (c == 0xFA) /* ACK */
                break;

            if (c == 0xFE) /* resend */
                continue;


            if (c == 0xFC) /* error */
                return FALSE;

            /* Some mice accidentally enter wrap mode during init */
            if (c == *(bytes + i)    /* wrap mode */
                && (*(bytes + i) != 0xEC)) /* avoid recursion */
                ps2DisableWrapMode(pInfo);

            return FALSE;
        }
        if (j == 10)
            return FALSE;
    }

    return TRUE;
}

static Bool
ps2DisableDataReporting(InputInfoPtr pInfo)
{
    unsigned char packet[] = { 0xF5 };
    return ps2SendPacket(pInfo, packet, sizeof(packet));
}

Bool
ps2EnableDataReporting(InputInfoPtr pInfo)
{
    unsigned char packet[] = { 0xF4 };
    return ps2SendPacket(pInfo, packet, sizeof(packet));
}

int
ps2GetDeviceID(InputInfoPtr pInfo)
{
    unsigned char u;
    unsigned char packet[] = { 0xf2 };

    usleep(30000);
    xf86FlushInput(pInfo->fd);
    if (!ps2SendPacket(pInfo, packet, sizeof(packet)))
        return -1;
    while (1) {
        if (!readMouse(pInfo,&u))
            return -1;
        if (u != 0xFA)
            break;
    }
#ifdef DEBUG
    xf86ErrorF("Obtained Mouse Type: %x\n",u);
#endif
    return (int) u;
}

Bool
ps2Reset(InputInfoPtr pInfo)
{
    unsigned char u;
    unsigned char packet[] = { 0xff };
    unsigned char reply[] = { 0xaa, 0x00 };
    unsigned int i;
#ifdef DEBUG
   xf86ErrorF("PS/2 Mouse reset\n");
#endif
    if (!ps2SendPacket(pInfo, packet, sizeof(packet)))
        return FALSE;
    /* we need a little delay here */
    xf86WaitForInput(pInfo->fd, 500000);
    for (i = 0; i < sizeof(reply) ; i++) {
        if (!readMouse(pInfo,&u)) {
            goto EXIT;
        }
        if (u != reply[i])
            goto EXIT;
    }
    return TRUE;

 EXIT:
    xf86FlushInput(pInfo->fd);
    return FALSE;
}

static MouseProtocolID
probePs2ProtocolPnP(InputInfoPtr pInfo)
{
    unsigned char u;
    MouseProtocolID ret = PROT_UNKNOWN;

    xf86FlushInput(pInfo->fd);

    ps2DisableDataReporting(pInfo);

    if (ps2Reset(pInfo)) { /* Reset PS2 device */
        unsigned char seq[] = { 243, 200, 243, 100, 243, 80 };
        /* Try to identify Intelli Mouse */
        if (ps2SendPacket(pInfo, seq, sizeof(seq))) {
            u = ps2GetDeviceID(pInfo);
            if (u == 0x03) {
                /* found IntelliMouse now try IntelliExplorer */
                unsigned char im_seq[] = { 243, 200, 243, 200, 243, 80 };
                if (ps2SendPacket(pInfo,im_seq,sizeof(im_seq))) {
                    u = ps2GetDeviceID(pInfo);
                    if (u == 0x04)
                        ret =  PROT_EXPPS2;
                    else
                        ret = PROT_IMPS2;
                }
            } else if (ps2Reset(pInfo))  /* reset again to find sane state */
                ret = PROT_PS2;
        }

        if (ret != PROT_UNKNOWN)
            ps2EnableDataReporting(pInfo);
    }
    return ret;
}

static struct ps2protos {
    int Id;
    MouseProtocolID protoID;
} ps2 [] = {
    { 0x0, PROT_PS2 },
    { 0x3, PROT_IMPS2 },
    { 0x4, PROT_EXPPS2 },
    { -1 , PROT_UNKNOWN }
};


static MouseProtocolID
getPs2ProtocolPnP(InputInfoPtr pInfo)
{
    int Id;
    int i;
    MouseProtocolID proto;
    int count = 4;

    xf86FlushInput(pInfo->fd);

    while (--count)
        if (ps2DisableDataReporting(pInfo))
            break;

    if (!count) {
        proto = PROT_UNKNOWN;
        goto EXIT;
    }

    if ((Id = ps2GetDeviceID(pInfo)) == -1) {
        proto = PROT_UNKNOWN;
        goto EXIT;
    }

    if (-1 == ps2EnableDataReporting(pInfo)) {
        proto = PROT_UNKNOWN;
        goto EXIT;
    }

    for (i = 0; ps2[i].protoID != PROT_UNKNOWN; i++) {
        if (ps2[i].Id == Id) {
            xf86MsgVerb(X_PROBED,2,"Found PS/2 proto ID %x\n",Id);
            proto =  ps2[i].protoID;
            goto EXIT;
        }
    }

    proto = PROT_UNKNOWN;
    xf86Msg(X_ERROR,"Found unknown PS/2 proto ID %x\n",Id);

 EXIT:
    xf86FlushInput(pInfo->fd);
    return proto;
}