isicom.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.
 *
 *  Original driver code supplied by Multi-Tech
 *
 *  Changes
 *  1/9/98  [email protected]
 *                  Merge to 2.0.x kernel tree
 *                  Obtain and use official major/minors
 *                  Loader switched to a misc device
 *                  (fixed range check bug as a side effect)
 *                  Printk clean up
 *  9/12/98 [email protected]
 *                  Rough port to 2.1.x
 *
 *  10/6/99 sameer          Merged the ISA and PCI drivers to
 *                  a new unified driver.
 *
 *  3/9/99  sameer          Added support for ISI4616 cards.
 *
 *  16/9/99 sameer          We do not force RTS low anymore.
 *                  This is to prevent the firmware
 *                  from getting confused.
 *
 *  26/10/99 sameer         Cosmetic changes:The driver now
 *                  dumps the Port Count information
 *                  along with I/O address and IRQ.
 *
 *  13/12/99 sameer         Fixed the problem with IRQ sharing.
 *
 *  10/5/00  sameer         Fixed isicom_shutdown_board()
 *                  to not lower DTR on all the ports
 *                  when the last port on the card is
 *                  closed.
 *
 *  10/5/00  sameer         Signal mask setup command added
 *                  to  isicom_setup_port and
 *                  isicom_shutdown_port.
 *
 *  24/5/00  sameer         The driver is now SMP aware.
 *
 *
 *  27/11/00 Vinayak P Risbud   Fixed the Driver Crash Problem
 *
 *
 *  03/01/01  anil .s       Added support for resetting the
 *                  internal modems on ISI cards.
 *
 *  08/02/01  anil .s       Upgraded the driver for kernel
 *                  2.4.x
 *
 *  11/04/01  Kevin         Fixed firmware load problem with
 *                  ISIHP-4X card
 *
 *  30/04/01  anil .s       Fixed the remote login through
 *                  ISI port problem. Now the link
 *                  does not go down before password
 *                  prompt.
 *
 *  03/05/01  anil .s       Fixed the problem with IRQ sharing
 *                  among ISI-PCI cards.
 *
 *  03/05/01  anil .s       Added support to display the version
 *                  info during insmod as well as module
 *                  listing by lsmod.
 *
 *  10/05/01  anil .s       Done the modifications to the source
 *                  file and Install script so that the
 *                  same installation can be used for
 *                  2.2.x and 2.4.x kernel.
 *
 *  06/06/01  anil .s       Now we drop both dtr and rts during
 *                  shutdown_port as well as raise them
 *                  during isicom_config_port.
 *
 *  09/06/01 [email protected]  use capable, not suser, do
 *                  restore_flags on failure in
 *                  isicom_send_break, verify put_user
 *                  result
 *
 *  11/02/03  ranjeeth      Added support for 230 Kbps and 460 Kbps
 *                  Baud index extended to 21
 *
 *  20/03/03  ranjeeth      Made to work for Linux Advanced server.
 *                  Taken care of license warning.
 *
 *  10/12/03  Ravindra      Made to work for Fedora Core 1 of
 *                  Red Hat Distribution
 *
 *  06/01/05  Alan Cox      Merged the ISI and base kernel strands
 *                  into a single 2.6 driver
 *
 *  ***********************************************************
 *
 *  To use this driver you also need the support package. You
 *  can find this in RPM format on
 *      ftp://ftp.linux.org.uk/pub/linux/alan
 *
 *  You can find the original tools for this direct from Multitech
 *      ftp://ftp.multitech.com/ISI-Cards/
 *
 *  Having installed the cards the module options (/etc/modprobe.d/)
 *
 *  options isicom   io=card1,card2,card3,card4 irq=card1,card2,card3,card4
 *
 *  Omit those entries for boards you don't have installed.
 *
 *  TODO
 *      Merge testing
 *      64-bit verification
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/termios.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/serial.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/slab.h>

#include <linux/uaccess.h>
#include <linux/io.h>

#include <linux/pci.h>

#include <linux/isicom.h>

#define InterruptTheCard(base) outw(0, (base) + 0xc)
#define ClearInterrupt(base) inw((base) + 0x0a)

#ifdef DEBUG
#define isicom_paranoia_check(a, b, c) __isicom_paranoia_check((a), (b), (c))
#else
#define isicom_paranoia_check(a, b, c) 0
#endif

static int isicom_probe(struct pci_dev *, const struct pci_device_id *);
static void __devexit isicom_remove(struct pci_dev *);

static struct pci_device_id isicom_pci_tbl[] = {
    { PCI_DEVICE(VENDOR_ID, 0x2028) },
    { PCI_DEVICE(VENDOR_ID, 0x2051) },
    { PCI_DEVICE(VENDOR_ID, 0x2052) },
    { PCI_DEVICE(VENDOR_ID, 0x2053) },
    { PCI_DEVICE(VENDOR_ID, 0x2054) },
    { PCI_DEVICE(VENDOR_ID, 0x2055) },
    { PCI_DEVICE(VENDOR_ID, 0x2056) },
    { PCI_DEVICE(VENDOR_ID, 0x2057) },
    { PCI_DEVICE(VENDOR_ID, 0x2058) },
    { 0 }
};
MODULE_DEVICE_TABLE(pci, isicom_pci_tbl);

static struct pci_driver isicom_driver = {
    .name       = "isicom",
    .id_table   = isicom_pci_tbl,
    .probe      = isicom_probe,
    .remove     = __devexit_p(isicom_remove)
};

static int prev_card = 3;   /*  start servicing isi_card[0] */
static struct tty_driver *isicom_normal;

static void isicom_tx(unsigned long _data);
static void isicom_start(struct tty_struct *tty);

static DEFINE_TIMER(tx, isicom_tx, 0, 0);

/*   baud index mappings from linux defns to isi */

static signed char linuxb_to_isib[] = {
    -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 18, 19, 20, 21
};

struct  isi_board {
    unsigned long       base;
    int         irq;
    unsigned char       port_count;
    unsigned short      status;
    unsigned short      port_status; /* each bit for each port */
    unsigned short      shift_count;
    struct isi_port     *ports;
    signed char     count;
    spinlock_t      card_lock; /* Card wide lock 11/5/00 -sameer */
    unsigned long       flags;
    unsigned int        index;
};

struct  isi_port {
    unsigned short      magic;
    struct tty_port     port;
    u16         channel;
    u16         status;
    struct isi_board    *card;
    unsigned char       *xmit_buf;
    int         xmit_head;
    int         xmit_tail;
    int         xmit_cnt;
};

static struct isi_board isi_card[BOARD_COUNT];
static struct isi_port  isi_ports[PORT_COUNT];

/*
 *  Locking functions for card level locking. We need to own both
 *  the kernel lock for the card and have the card in a position that
 *  it wants to talk.
 */

static inline int WaitTillCardIsFree(unsigned long base)
{
    unsigned int count = 0;
    unsigned int a = in_atomic(); /* do we run under spinlock? */

    while (!(inw(base + 0xe) & 0x1) && count++ < 100)
        if (a)
            mdelay(1);
        else
            msleep(1);

    return !(inw(base + 0xe) & 0x1);
}

static int lock_card(struct isi_board *card)
{
    unsigned long base = card->base;
    unsigned int retries, a;

    for (retries = 0; retries < 10; retries++) {
        spin_lock_irqsave(&card->card_lock, card->flags);
        for (a = 0; a < 10; a++) {
            if (inw(base + 0xe) & 0x1)
                return 1;
            udelay(10);
        }
        spin_unlock_irqrestore(&card->card_lock, card->flags);
        msleep(10);
    }
    pr_warning("Failed to lock Card (0x%lx)\n", card->base);

    return 0;   /* Failed to acquire the card! */
}

static void unlock_card(struct isi_board *card)
{
    spin_unlock_irqrestore(&card->card_lock, card->flags);
}

/*
 *  ISI Card specific ops ...
 */

/* card->lock HAS to be held */
static void raise_dtr(struct isi_port *port)
{
    struct isi_board *card = port->card;
    unsigned long base = card->base;
    u16 channel = port->channel;

    if (WaitTillCardIsFree(base))
        return;

    outw(0x8000 | (channel << card->shift_count) | 0x02, base);
    outw(0x0504, base);
    InterruptTheCard(base);
    port->status |= ISI_DTR;
}

/* card->lock HAS to be held */
static inline void drop_dtr(struct isi_port *port)
{
    struct isi_board *card = port->card;
    unsigned long base = card->base;
    u16 channel = port->channel;

    if (WaitTillCardIsFree(base))
        return;

    outw(0x8000 | (channel << card->shift_count) | 0x02, base);
    outw(0x0404, base);
    InterruptTheCard(base);
    port->status &= ~ISI_DTR;
}

/* card->lock HAS to be held */
static inline void raise_rts(struct isi_port *port)
{
    struct isi_board *card = port->card;
    unsigned long base = card->base;
    u16 channel = port->channel;

    if (WaitTillCardIsFree(base))
        return;

    outw(0x8000 | (channel << card->shift_count) | 0x02, base);
    outw(0x0a04, base);
    InterruptTheCard(base);
    port->status |= ISI_RTS;
}

/* card->lock HAS to be held */
static inline void drop_rts(struct isi_port *port)
{
    struct isi_board *card = port->card;
    unsigned long base = card->base;
    u16 channel = port->channel;

    if (WaitTillCardIsFree(base))
        return;

    outw(0x8000 | (channel << card->shift_count) | 0x02, base);
    outw(0x0804, base);
    InterruptTheCard(base);
    port->status &= ~ISI_RTS;
}

/* card->lock MUST NOT be held */

static void isicom_dtr_rts(struct tty_port *port, int on)
{
    struct isi_port *ip = container_of(port, struct isi_port, port);
    struct isi_board *card = ip->card;
    unsigned long base = card->base;
    u16 channel = ip->channel;

    if (!lock_card(card))
        return;

    if (on) {
        outw(0x8000 | (channel << card->shift_count) | 0x02, base);
        outw(0x0f04, base);
        InterruptTheCard(base);
        ip->status |= (ISI_DTR | ISI_RTS);
    } else {
        outw(0x8000 | (channel << card->shift_count) | 0x02, base);
        outw(0x0C04, base);
        InterruptTheCard(base);
        ip->status &= ~(ISI_DTR | ISI_RTS);
    }
    unlock_card(card);
}

/* card->lock HAS to be held */
static void drop_dtr_rts(struct isi_port *port)
{
    struct isi_board *card = port->card;
    unsigned long base = card->base;
    u16 channel = port->channel;

    if (WaitTillCardIsFree(base))
        return;

    outw(0x8000 | (channel << card->shift_count) | 0x02, base);
    outw(0x0c04, base);
    InterruptTheCard(base);
    port->status &= ~(ISI_RTS | ISI_DTR);
}

/*
 *  ISICOM Driver specific routines ...
 *
 */

static inline int __isicom_paranoia_check(struct isi_port const *port,
    char *name, const char *routine)
{
    if (!port) {
        pr_warning("Warning: bad isicom magic for dev %s in %s.\n",
               name, routine);
        return 1;
    }
    if (port->magic != ISICOM_MAGIC) {
        pr_warning("Warning: NULL isicom port for dev %s in %s.\n",
               name, routine);
        return 1;
    }

    return 0;
}

/*
 *  Transmitter.
 *
 *  We shovel data into the card buffers on a regular basis. The card
 *  will do the rest of the work for us.
 */

static void isicom_tx(unsigned long _data)
{
    unsigned long flags, base;
    unsigned int retries;
    short count = (BOARD_COUNT-1), card;
    short txcount, wrd, residue, word_count, cnt;
    struct isi_port *port;
    struct tty_struct *tty;

    /*  find next active board  */
    card = (prev_card + 1) & 0x0003;
    while (count-- > 0) {
        if (isi_card[card].status & BOARD_ACTIVE)
            break;
        card = (card + 1) & 0x0003;
    }
    if (!(isi_card[card].status & BOARD_ACTIVE))
        goto sched_again;

    prev_card = card;

    count = isi_card[card].port_count;
    port = isi_card[card].ports;
    base = isi_card[card].base;

    spin_lock_irqsave(&isi_card[card].card_lock, flags);
    for (retries = 0; retries < 100; retries++) {
        if (inw(base + 0xe) & 0x1)
            break;
        udelay(2);
    }
    if (retries >= 100)
        goto unlock;

    tty = tty_port_tty_get(&port->port);
    if (tty == NULL)
        goto put_unlock;

    for (; count > 0; count--, port++) {
        /* port not active or tx disabled to force flow control */
        if (!(port->port.flags & ASYNC_INITIALIZED) ||
                !(port->status & ISI_TXOK))
            continue;

        txcount = min_t(short, TX_SIZE, port->xmit_cnt);
        if (txcount <= 0 || tty->stopped || tty->hw_stopped)
            continue;

        if (!(inw(base + 0x02) & (1 << port->channel)))
            continue;

        pr_debug("txing %d bytes, port%d.\n",
             txcount, port->channel + 1);
        outw((port->channel << isi_card[card].shift_count) | txcount,
            base);
        residue = NO;
        wrd = 0;
        while (1) {
            cnt = min_t(int, txcount, (SERIAL_XMIT_SIZE
                    - port->xmit_tail));
            if (residue == YES) {
                residue = NO;
                if (cnt > 0) {
                    wrd |= (port->port.xmit_buf[port->xmit_tail]
                                    << 8);
                    port->xmit_tail = (port->xmit_tail + 1)
                        & (SERIAL_XMIT_SIZE - 1);
                    port->xmit_cnt--;
                    txcount--;
                    cnt--;
                    outw(wrd, base);
                } else {
                    outw(wrd, base);
                    break;
                }
            }
            if (cnt <= 0)
                break;
            word_count = cnt >> 1;
            outsw(base, port->port.xmit_buf+port->xmit_tail, word_count);
            port->xmit_tail = (port->xmit_tail
                + (word_count << 1)) & (SERIAL_XMIT_SIZE - 1);
            txcount -= (word_count << 1);
            port->xmit_cnt -= (word_count << 1);
            if (cnt & 0x0001) {
                residue = YES;
                wrd = port->port.xmit_buf[port->xmit_tail];
                port->xmit_tail = (port->xmit_tail + 1)
                    & (SERIAL_XMIT_SIZE - 1);
                port->xmit_cnt--;
                txcount--;
            }
        }

        InterruptTheCard(base);
        if (port->xmit_cnt <= 0)
            port->status &= ~ISI_TXOK;
        if (port->xmit_cnt <= WAKEUP_CHARS)
            tty_wakeup(tty);
    }

put_unlock:
    tty_kref_put(tty);
unlock:
    spin_unlock_irqrestore(&isi_card[card].card_lock, flags);
    /*  schedule another tx for hopefully in about 10ms */
sched_again:
    mod_timer(&tx, jiffies + msecs_to_jiffies(10));
}

/*
 *  Main interrupt handler routine
 */

static irqreturn_t isicom_interrupt(int irq, void *dev_id)
{
    struct isi_board *card = dev_id;
    struct isi_port *port;
    struct tty_struct *tty;
    unsigned long base;
    u16 header, word_count, count, channel;
    short byte_count;
    unsigned char *rp;

    if (!card || !(card->status & FIRMWARE_LOADED))
        return IRQ_NONE;

    base = card->base;

    /* did the card interrupt us? */
    if (!(inw(base + 0x0e) & 0x02))
        return IRQ_NONE;

    spin_lock(&card->card_lock);

    /*
     * disable any interrupts from the PCI card and lower the
     * interrupt line
     */
    outw(0x8000, base+0x04);
    ClearInterrupt(base);

    inw(base);      /* get the dummy word out */
    header = inw(base);
    channel = (header & 0x7800) >> card->shift_count;
    byte_count = header & 0xff;

    if (channel + 1 > card->port_count) {
        pr_warning("%s(0x%lx): %d(channel) > port_count.\n",
               __func__, base, channel+1);
        outw(0x0000, base+0x04); /* enable interrupts */
        spin_unlock(&card->card_lock);
        return IRQ_HANDLED;
    }
    port = card->ports + channel;
    if (!(port->port.flags & ASYNC_INITIALIZED)) {
        outw(0x0000, base+0x04); /* enable interrupts */
        spin_unlock(&card->card_lock);
        return IRQ_HANDLED;
    }

    tty = tty_port_tty_get(&port->port);
    if (tty == NULL) {
        word_count = byte_count >> 1;
        while (byte_count > 1) {
            inw(base);
            byte_count -= 2;
        }
        if (byte_count & 0x01)
            inw(base);
        outw(0x0000, base+0x04); /* enable interrupts */
        spin_unlock(&card->card_lock);
        return IRQ_HANDLED;
    }

    if (header & 0x8000) {      /* Status Packet */
        header = inw(base);
        switch (header & 0xff) {
        case 0: /* Change in EIA signals */
            if (port->port.flags & ASYNC_CHECK_CD) {
                if (port->status & ISI_DCD) {
                    if (!(header & ISI_DCD)) {
                    /* Carrier has been lost  */
                        pr_debug("%s: DCD->low.\n",
                             __func__);
                        port->status &= ~ISI_DCD;
                        tty_hangup(tty);
                    }
                } else if (header & ISI_DCD) {
                /* Carrier has been detected */
                    pr_debug("%s: DCD->high.\n",
                        __func__);
                    port->status |= ISI_DCD;
                    wake_up_interruptible(&port->port.open_wait);
                }
            } else {
                if (header & ISI_DCD)
                    port->status |= ISI_DCD;
                else
                    port->status &= ~ISI_DCD;
            }

            if (tty_port_cts_enabled(&port->port)) {
                if (tty->hw_stopped) {
                    if (header & ISI_CTS) {
                        port->port.tty->hw_stopped = 0;
                        /* start tx ing */
                        port->status |= (ISI_TXOK
                            | ISI_CTS);
                        tty_wakeup(tty);
                    }
                } else if (!(header & ISI_CTS)) {
                    tty->hw_stopped = 1;
                    /* stop tx ing */
                    port->status &= ~(ISI_TXOK | ISI_CTS);
                }
            } else {
                if (header & ISI_CTS)
                    port->status |= ISI_CTS;
                else
                    port->status &= ~ISI_CTS;
            }

            if (header & ISI_DSR)
                port->status |= ISI_DSR;
            else
                port->status &= ~ISI_DSR;

            if (header & ISI_RI)
                port->status |= ISI_RI;
            else
                port->status &= ~ISI_RI;

            break;

        case 1: /* Received Break !!! */
            tty_insert_flip_char(tty, 0, TTY_BREAK);
            if (port->port.flags & ASYNC_SAK)
                do_SAK(tty);
            tty_flip_buffer_push(tty);
            break;

        case 2: /* Statistics        */
            pr_debug("%s: stats!!!\n", __func__);
            break;

        default:
            pr_debug("%s: Unknown code in status packet.\n",
                 __func__);
            break;
        }
    } else {                /* Data   Packet */

        count = tty_prepare_flip_string(tty, &rp, byte_count & ~1);
        pr_debug("%s: Can rx %d of %d bytes.\n",
             __func__, count, byte_count);
        word_count = count >> 1;
        insw(base, rp, word_count);
        byte_count -= (word_count << 1);
        if (count & 0x0001) {
            tty_insert_flip_char(tty,  inw(base) & 0xff,
                TTY_NORMAL);
            byte_count -= 2;
        }
        if (byte_count > 0) {
            pr_debug("%s(0x%lx:%d): Flip buffer overflow! dropping bytes...\n",
                 __func__, base, channel + 1);
        /* drain out unread xtra data */
        while (byte_count > 0) {
                inw(base);
                byte_count -= 2;
            }
        }
        tty_flip_buffer_push(tty);
    }
    outw(0x0000, base+0x04); /* enable interrupts */
    spin_unlock(&card->card_lock);
    tty_kref_put(tty);

    return IRQ_HANDLED;
}

static void isicom_config_port(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;
    unsigned long baud;
    unsigned long base = card->base;
    u16 channel_setup, channel = port->channel,
        shift_count = card->shift_count;
    unsigned char flow_ctrl;

    /* FIXME: Switch to new tty baud API */
    baud = C_BAUD(tty);
    if (baud & CBAUDEX) {
        baud &= ~CBAUDEX;

        /*  if CBAUDEX bit is on and the baud is set to either 50 or 75
         *  then the card is programmed for 57.6Kbps or 115Kbps
         *  respectively.
         */

        /* 1,2,3,4 => 57.6, 115.2, 230, 460 kbps resp. */
        if (baud < 1 || baud > 4)
            tty->termios.c_cflag &= ~CBAUDEX;
        else
            baud += 15;
    }
    if (baud == 15) {

        /*  the ASYNC_SPD_HI and ASYNC_SPD_VHI options are set
         *  by the set_serial_info ioctl ... this is done by
         *  the 'setserial' utility.
         */

        if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
            baud++; /*  57.6 Kbps */
        if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
            baud += 2; /*  115  Kbps */
        if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
            baud += 3; /* 230 kbps*/
        if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
            baud += 4; /* 460 kbps*/
    }
    if (linuxb_to_isib[baud] == -1) {
        /* hang up */
        drop_dtr(port);
        return;
    } else
        raise_dtr(port);

    if (WaitTillCardIsFree(base) == 0) {
        outw(0x8000 | (channel << shift_count) | 0x03, base);
        outw(linuxb_to_isib[baud] << 8 | 0x03, base);
        channel_setup = 0;
        switch (C_CSIZE(tty)) {
        case CS5:
            channel_setup |= ISICOM_CS5;
            break;
        case CS6:
            channel_setup |= ISICOM_CS6;
            break;
        case CS7:
            channel_setup |= ISICOM_CS7;
            break;
        case CS8:
            channel_setup |= ISICOM_CS8;
            break;
        }

        if (C_CSTOPB(tty))
            channel_setup |= ISICOM_2SB;
        if (C_PARENB(tty)) {
            channel_setup |= ISICOM_EVPAR;
            if (C_PARODD(tty))
                channel_setup |= ISICOM_ODPAR;
        }
        outw(channel_setup, base);
        InterruptTheCard(base);
    }
    if (C_CLOCAL(tty))
        port->port.flags &= ~ASYNC_CHECK_CD;
    else
        port->port.flags |= ASYNC_CHECK_CD;

    /* flow control settings ...*/
    flow_ctrl = 0;
    port->port.flags &= ~ASYNC_CTS_FLOW;
    if (C_CRTSCTS(tty)) {
        port->port.flags |= ASYNC_CTS_FLOW;
        flow_ctrl |= ISICOM_CTSRTS;
    }
    if (I_IXON(tty))
        flow_ctrl |= ISICOM_RESPOND_XONXOFF;
    if (I_IXOFF(tty))
        flow_ctrl |= ISICOM_INITIATE_XONXOFF;

    if (WaitTillCardIsFree(base) == 0) {
        outw(0x8000 | (channel << shift_count) | 0x04, base);
        outw(flow_ctrl << 8 | 0x05, base);
        outw((STOP_CHAR(tty)) << 8 | (START_CHAR(tty)), base);
        InterruptTheCard(base);
    }

    /*  rx enabled -> enable port for rx on the card    */
    if (C_CREAD(tty)) {
        card->port_status |= (1 << channel);
        outw(card->port_status, base + 0x02);
    }
}

/* open et all */

static inline void isicom_setup_board(struct isi_board *bp)
{
    int channel;
    struct isi_port *port;

    bp->count++;
    if (!(bp->status & BOARD_INIT)) {
        port = bp->ports;
        for (channel = 0; channel < bp->port_count; channel++, port++)
            drop_dtr_rts(port);
    }
    bp->status |= BOARD_ACTIVE | BOARD_INIT;
}

/* Activate and thus setup board are protected from races against shutdown
   by the tty_port mutex */

static int isicom_activate(struct tty_port *tport, struct tty_struct *tty)
{
    struct isi_port *port = container_of(tport, struct isi_port, port);
    struct isi_board *card = port->card;
    unsigned long flags;

    if (tty_port_alloc_xmit_buf(tport) < 0)
        return -ENOMEM;

    spin_lock_irqsave(&card->card_lock, flags);
    isicom_setup_board(card);

    port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;

    /*  discard any residual data   */
    if (WaitTillCardIsFree(card->base) == 0) {
        outw(0x8000 | (port->channel << card->shift_count) | 0x02,
                card->base);
        outw(((ISICOM_KILLTX | ISICOM_KILLRX) << 8) | 0x06, card->base);
        InterruptTheCard(card->base);
    }
    isicom_config_port(tty);
    spin_unlock_irqrestore(&card->card_lock, flags);

    return 0;
}

static int isicom_carrier_raised(struct tty_port *port)
{
    struct isi_port *ip = container_of(port, struct isi_port, port);
    return (ip->status & ISI_DCD)?1 : 0;
}

static struct tty_port *isicom_find_port(struct tty_struct *tty)
{
    struct isi_port *port;
    struct isi_board *card;
    unsigned int board;
    int line = tty->index;

    board = BOARD(line);
    card = &isi_card[board];

    if (!(card->status & FIRMWARE_LOADED))
        return NULL;

    /*  open on a port greater than the port count for the card !!! */
    if (line > ((board * 16) + card->port_count - 1))
        return NULL;

    port = &isi_ports[line];
    if (isicom_paranoia_check(port, tty->name, "isicom_open"))
        return NULL;

    return &port->port;
}

static int isicom_open(struct tty_struct *tty, struct file *filp)
{
    struct isi_port *port;
    struct tty_port *tport;

    tport = isicom_find_port(tty);
    if (tport == NULL)
        return -ENODEV;
    port = container_of(tport, struct isi_port, port);

    tty->driver_data = port;
    return tty_port_open(tport, tty, filp);
}

/* close et all */

/* card->lock HAS to be held */
static void isicom_shutdown_port(struct isi_port *port)
{
    struct isi_board *card = port->card;

    if (--card->count < 0) {
        pr_debug("%s: bad board(0x%lx) count %d.\n",
             __func__, card->base, card->count);
        card->count = 0;
    }
    /* last port was closed, shutdown that board too */
    if (!card->count)
        card->status &= BOARD_ACTIVE;
}

static void isicom_flush_buffer(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;
    unsigned long flags;

    if (isicom_paranoia_check(port, tty->name, "isicom_flush_buffer"))
        return;

    spin_lock_irqsave(&card->card_lock, flags);
    port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
    spin_unlock_irqrestore(&card->card_lock, flags);

    tty_wakeup(tty);
}

static void isicom_shutdown(struct tty_port *port)
{
    struct isi_port *ip = container_of(port, struct isi_port, port);
    struct isi_board *card = ip->card;
    unsigned long flags;

    /* indicate to the card that no more data can be received
       on this port */
    spin_lock_irqsave(&card->card_lock, flags);
    card->port_status &= ~(1 << ip->channel);
    outw(card->port_status, card->base + 0x02);
    isicom_shutdown_port(ip);
    spin_unlock_irqrestore(&card->card_lock, flags);
    tty_port_free_xmit_buf(port);
}

static void isicom_close(struct tty_struct *tty, struct file *filp)
{
    struct isi_port *ip = tty->driver_data;
    struct tty_port *port;

    if (ip == NULL)
        return;

    port = &ip->port;
    if (isicom_paranoia_check(ip, tty->name, "isicom_close"))
        return;
    tty_port_close(port, tty, filp);
}

/* write et all */
static int isicom_write(struct tty_struct *tty, const unsigned char *buf,
    int count)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;
    unsigned long flags;
    int cnt, total = 0;

    if (isicom_paranoia_check(port, tty->name, "isicom_write"))
        return 0;

    spin_lock_irqsave(&card->card_lock, flags);

    while (1) {
        cnt = min_t(int, count, min(SERIAL_XMIT_SIZE - port->xmit_cnt
                - 1, SERIAL_XMIT_SIZE - port->xmit_head));
        if (cnt <= 0)
            break;

        memcpy(port->port.xmit_buf + port->xmit_head, buf, cnt);
        port->xmit_head = (port->xmit_head + cnt) & (SERIAL_XMIT_SIZE
            - 1);
        port->xmit_cnt += cnt;
        buf += cnt;
        count -= cnt;
        total += cnt;
    }
    if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped)
        port->status |= ISI_TXOK;
    spin_unlock_irqrestore(&card->card_lock, flags);
    return total;
}

/* put_char et all */
static int isicom_put_char(struct tty_struct *tty, unsigned char ch)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;
    unsigned long flags;

    if (isicom_paranoia_check(port, tty->name, "isicom_put_char"))
        return 0;

    spin_lock_irqsave(&card->card_lock, flags);
    if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
        spin_unlock_irqrestore(&card->card_lock, flags);
        return 0;
    }

    port->port.xmit_buf[port->xmit_head++] = ch;
    port->xmit_head &= (SERIAL_XMIT_SIZE - 1);
    port->xmit_cnt++;
    spin_unlock_irqrestore(&card->card_lock, flags);
    return 1;
}

/* flush_chars et all */
static void isicom_flush_chars(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;

    if (isicom_paranoia_check(port, tty->name, "isicom_flush_chars"))
        return;

    if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
            !port->port.xmit_buf)
        return;

    /* this tells the transmitter to consider this port for
       data output to the card ... that's the best we can do. */
    port->status |= ISI_TXOK;
}

/* write_room et all */
static int isicom_write_room(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    int free;

    if (isicom_paranoia_check(port, tty->name, "isicom_write_room"))
        return 0;

    free = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
    if (free < 0)
        free = 0;
    return free;
}

/* chars_in_buffer et all */
static int isicom_chars_in_buffer(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    if (isicom_paranoia_check(port, tty->name, "isicom_chars_in_buffer"))
        return 0;
    return port->xmit_cnt;
}

/* ioctl et all */
static int isicom_send_break(struct tty_struct *tty, int length)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;
    unsigned long base = card->base;

    if (length == -1)
        return -EOPNOTSUPP;

    if (!lock_card(card))
        return -EINVAL;

    outw(0x8000 | ((port->channel) << (card->shift_count)) | 0x3, base);
    outw((length & 0xff) << 8 | 0x00, base);
    outw((length & 0xff00), base);
    InterruptTheCard(base);

    unlock_card(card);
    return 0;
}

static int isicom_tiocmget(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    /* just send the port status */
    u16 status = port->status;

    if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
        return -ENODEV;

    return  ((status & ISI_RTS) ? TIOCM_RTS : 0) |
        ((status & ISI_DTR) ? TIOCM_DTR : 0) |
        ((status & ISI_DCD) ? TIOCM_CAR : 0) |
        ((status & ISI_DSR) ? TIOCM_DSR : 0) |
        ((status & ISI_CTS) ? TIOCM_CTS : 0) |
        ((status & ISI_RI ) ? TIOCM_RI  : 0);
}

static int isicom_tiocmset(struct tty_struct *tty,
                    unsigned int set, unsigned int clear)
{
    struct isi_port *port = tty->driver_data;
    unsigned long flags;

    if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
        return -ENODEV;

    spin_lock_irqsave(&port->card->card_lock, flags);
    if (set & TIOCM_RTS)
        raise_rts(port);
    if (set & TIOCM_DTR)
        raise_dtr(port);

    if (clear & TIOCM_RTS)
        drop_rts(port);
    if (clear & TIOCM_DTR)
        drop_dtr(port);
    spin_unlock_irqrestore(&port->card->card_lock, flags);

    return 0;
}

static int isicom_set_serial_info(struct tty_struct *tty,
                    struct serial_struct __user *info)
{
    struct isi_port *port = tty->driver_data;
    struct serial_struct newinfo;
    int reconfig_port;

    if (copy_from_user(&newinfo, info, sizeof(newinfo)))
        return -EFAULT;

    mutex_lock(&port->port.mutex);
    reconfig_port = ((port->port.flags & ASYNC_SPD_MASK) !=
        (newinfo.flags & ASYNC_SPD_MASK));

    if (!capable(CAP_SYS_ADMIN)) {
        if ((newinfo.close_delay != port->port.close_delay) ||
                (newinfo.closing_wait != port->port.closing_wait) ||
                ((newinfo.flags & ~ASYNC_USR_MASK) !=
                (port->port.flags & ~ASYNC_USR_MASK))) {
            mutex_unlock(&port->port.mutex);
            return -EPERM;
        }
        port->port.flags = ((port->port.flags & ~ASYNC_USR_MASK) |
                (newinfo.flags & ASYNC_USR_MASK));
    } else {
        port->port.close_delay = newinfo.close_delay;
        port->port.closing_wait = newinfo.closing_wait;
        port->port.flags = ((port->port.flags & ~ASYNC_FLAGS) |
                (newinfo.flags & ASYNC_FLAGS));
    }
    if (reconfig_port) {
        unsigned long flags;
        spin_lock_irqsave(&port->card->card_lock, flags);
        isicom_config_port(tty);
        spin_unlock_irqrestore(&port->card->card_lock, flags);
    }
    mutex_unlock(&port->port.mutex);
    return 0;
}

static int isicom_get_serial_info(struct isi_port *port,
    struct serial_struct __user *info)
{
    struct serial_struct out_info;

    mutex_lock(&port->port.mutex);
    memset(&out_info, 0, sizeof(out_info));
/*  out_info.type = ? */
    out_info.line = port - isi_ports;
    out_info.port = port->card->base;
    out_info.irq = port->card->irq;
    out_info.flags = port->port.flags;
/*  out_info.baud_base = ? */
    out_info.close_delay = port->port.close_delay;
    out_info.closing_wait = port->port.closing_wait;
    mutex_unlock(&port->port.mutex);
    if (copy_to_user(info, &out_info, sizeof(out_info)))
        return -EFAULT;
    return 0;
}

static int isicom_ioctl(struct tty_struct *tty,
    unsigned int cmd, unsigned long arg)
{
    struct isi_port *port = tty->driver_data;
    void __user *argp = (void __user *)arg;

    if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
        return -ENODEV;

    switch (cmd) {
    case TIOCGSERIAL:
        return isicom_get_serial_info(port, argp);

    case TIOCSSERIAL:
        return isicom_set_serial_info(tty, argp);

    default:
        return -ENOIOCTLCMD;
    }
    return 0;
}

/* set_termios et all */
static void isicom_set_termios(struct tty_struct *tty,
    struct ktermios *old_termios)
{
    struct isi_port *port = tty->driver_data;
    unsigned long flags;

    if (isicom_paranoia_check(port, tty->name, "isicom_set_termios"))
        return;

    if (tty->termios.c_cflag == old_termios->c_cflag &&
            tty->termios.c_iflag == old_termios->c_iflag)
        return;

    spin_lock_irqsave(&port->card->card_lock, flags);
    isicom_config_port(tty);
    spin_unlock_irqrestore(&port->card->card_lock, flags);

    if ((old_termios->c_cflag & CRTSCTS) &&
            !(tty->termios.c_cflag & CRTSCTS)) {
        tty->hw_stopped = 0;
        isicom_start(tty);
    }
}

/* throttle et all */
static void isicom_throttle(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;

    if (isicom_paranoia_check(port, tty->name, "isicom_throttle"))
        return;

    /* tell the card that this port cannot handle any more data for now */
    card->port_status &= ~(1 << port->channel);
    outw(card->port_status, card->base + 0x02);
}

/* unthrottle et all */
static void isicom_unthrottle(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;
    struct isi_board *card = port->card;

    if (isicom_paranoia_check(port, tty->name, "isicom_unthrottle"))
        return;

    /* tell the card that this port is ready to accept more data */
    card->port_status |= (1 << port->channel);
    outw(card->port_status, card->base + 0x02);
}

/* stop et all */
static void isicom_stop(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;

    if (isicom_paranoia_check(port, tty->name, "isicom_stop"))
        return;

    /* this tells the transmitter not to consider this port for
       data output to the card. */
    port->status &= ~ISI_TXOK;
}

/* start et all */
static void isicom_start(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;

    if (isicom_paranoia_check(port, tty->name, "isicom_start"))
        return;

    /* this tells the transmitter to consider this port for
       data output to the card. */
    port->status |= ISI_TXOK;
}

static void isicom_hangup(struct tty_struct *tty)
{
    struct isi_port *port = tty->driver_data;

    if (isicom_paranoia_check(port, tty->name, "isicom_hangup"))
        return;
    tty_port_hangup(&port->port);
}


/*
 * Driver init and deinit functions
 */

static const struct tty_operations isicom_ops = {
    .open           = isicom_open,
    .close          = isicom_close,
    .write          = isicom_write,
    .put_char       = isicom_put_char,
    .flush_chars        = isicom_flush_chars,
    .write_room     = isicom_write_room,
    .chars_in_buffer    = isicom_chars_in_buffer,
    .ioctl          = isicom_ioctl,
    .set_termios        = isicom_set_termios,
    .throttle       = isicom_throttle,
    .unthrottle     = isicom_unthrottle,
    .stop           = isicom_stop,
    .start          = isicom_start,
    .hangup         = isicom_hangup,
    .flush_buffer       = isicom_flush_buffer,
    .tiocmget       = isicom_tiocmget,
    .tiocmset       = isicom_tiocmset,
    .break_ctl      = isicom_send_break,
};

static const struct tty_port_operations isicom_port_ops = {
    .carrier_raised     = isicom_carrier_raised,
    .dtr_rts        = isicom_dtr_rts,
    .activate       = isicom_activate,
    .shutdown       = isicom_shutdown,
};

static int __devinit reset_card(struct pci_dev *pdev,
    const unsigned int card, unsigned int *signature)
{
    struct isi_board *board = pci_get_drvdata(pdev);
    unsigned long base = board->base;
    unsigned int sig, portcount = 0;
    int retval = 0;

    dev_dbg(&pdev->dev, "ISILoad:Resetting Card%d at 0x%lx\n", card + 1,
        base);

    inw(base + 0x8);

    msleep(10);

    outw(0, base + 0x8); /* Reset */

    msleep(1000);

    sig = inw(base + 0x4) & 0xff;

    if (sig != 0xa5 && sig != 0xbb && sig != 0xcc && sig != 0xdd &&
            sig != 0xee) {
        dev_warn(&pdev->dev, "ISILoad:Card%u reset failure (Possible "
            "bad I/O Port Address 0x%lx).\n", card + 1, base);
        dev_dbg(&pdev->dev, "Sig=0x%x\n", sig);
        retval = -EIO;
        goto end;
    }

    msleep(10);

    portcount = inw(base + 0x2);
    if (!(inw(base + 0xe) & 0x1) || (portcount != 0 && portcount != 4 &&
                portcount != 8 && portcount != 16)) {
        dev_err(&pdev->dev, "ISILoad:PCI Card%d reset failure.\n",
            card + 1);
        retval = -EIO;
        goto end;
    }

    switch (sig) {
    case 0xa5:
    case 0xbb:
    case 0xdd:
        board->port_count = (portcount == 4) ? 4 : 8;
        board->shift_count = 12;
        break;
    case 0xcc:
    case 0xee:
        board->port_count = 16;
        board->shift_count = 11;
        break;
    }
    dev_info(&pdev->dev, "-Done\n");
    *signature = sig;

end:
    return retval;
}

static int __devinit load_firmware(struct pci_dev *pdev,
    const unsigned int index, const unsigned int signature)
{
    struct isi_board *board = pci_get_drvdata(pdev);
    const struct firmware *fw;
    unsigned long base = board->base;
    unsigned int a;
    u16 word_count, status;
    int retval = -EIO;
    char *name;
    u8 *data;

    struct stframe {
        u16 addr;
        u16 count;
        u8  data[0];
    } *frame;

    switch (signature) {
    case 0xa5:
        name = "isi608.bin";
        break;
    case 0xbb:
        name = "isi608em.bin";
        break;
    case 0xcc:
        name = "isi616em.bin";
        break;
    case 0xdd:
        name = "isi4608.bin";
        break;
    case 0xee:
        name = "isi4616.bin";
        break;
    default:
        dev_err(&pdev->dev, "Unknown signature.\n");
        goto end;
    }

    retval = request_firmware(&fw, name, &pdev->dev);
    if (retval)
        goto end;

    retval = -EIO;

    for (frame = (struct stframe *)fw->data;
            frame < (struct stframe *)(fw->data + fw->size);
            frame = (struct stframe *)((u8 *)(frame + 1) +
                frame->count)) {
        if (WaitTillCardIsFree(base))
            goto errrelfw;

        outw(0xf0, base);   /* start upload sequence */
        outw(0x00, base);
        outw(frame->addr, base); /* lsb of address */

        word_count = frame->count / 2 + frame->count % 2;
        outw(word_count, base);
        InterruptTheCard(base);

        udelay(100); /* 0x2f */

        if (WaitTillCardIsFree(base))
            goto errrelfw;

        status = inw(base + 0x4);
        if (status != 0) {
            dev_warn(&pdev->dev, "Card%d rejected load header:\n"
                 "Address:0x%x\n"
                 "Count:0x%x\n"
                 "Status:0x%x\n",
                 index + 1, frame->addr, frame->count, status);
            goto errrelfw;
        }
        outsw(base, frame->data, word_count);

        InterruptTheCard(base);

        udelay(50); /* 0x0f */

        if (WaitTillCardIsFree(base))
            goto errrelfw;

        status = inw(base + 0x4);
        if (status != 0) {
            dev_err(&pdev->dev, "Card%d got out of sync.Card "
                "Status:0x%x\n", index + 1, status);
            goto errrelfw;
        }
    }

/* XXX: should we test it by reading it back and comparing with original like
 * in load firmware package? */
    for (frame = (struct stframe *)fw->data;
            frame < (struct stframe *)(fw->data + fw->size);
            frame = (struct stframe *)((u8 *)(frame + 1) +
                frame->count)) {
        if (WaitTillCardIsFree(base))
            goto errrelfw;

        outw(0xf1, base); /* start download sequence */
        outw(0x00, base);
        outw(frame->addr, base); /* lsb of address */

        word_count = (frame->count >> 1) + frame->count % 2;
        outw(word_count + 1, base);
        InterruptTheCard(base);

        udelay(50); /* 0xf */

        if (WaitTillCardIsFree(base))
            goto errrelfw;

        status = inw(base + 0x4);
        if (status != 0) {
            dev_warn(&pdev->dev, "Card%d rejected verify header:\n"
                 "Address:0x%x\n"
                 "Count:0x%x\n"
                 "Status: 0x%x\n",
                 index + 1, frame->addr, frame->count, status);
            goto errrelfw;
        }

        data = kmalloc(word_count * 2, GFP_KERNEL);
        if (data == NULL) {
            dev_err(&pdev->dev, "Card%d, firmware upload "
                "failed, not enough memory\n", index + 1);
            goto errrelfw;
        }
        inw(base);
        insw(base, data, word_count);
        InterruptTheCard(base);

        for (a = 0; a < frame->count; a++)
            if (data[a] != frame->data[a]) {
                kfree(data);
                dev_err(&pdev->dev, "Card%d, firmware upload "
                    "failed\n", index + 1);
                goto errrelfw;
            }
        kfree(data);

        udelay(50); /* 0xf */

        if (WaitTillCardIsFree(base))
            goto errrelfw;

        status = inw(base + 0x4);
        if (status != 0) {
            dev_err(&pdev->dev, "Card%d verify got out of sync. "
                "Card Status:0x%x\n", index + 1, status);
            goto errrelfw;
        }
    }

    /* xfer ctrl */
    if (WaitTillCardIsFree(base))
        goto errrelfw;

    outw(0xf2, base);
    outw(0x800, base);
    outw(0x0, base);
    outw(0x0, base);
    InterruptTheCard(base);
    outw(0x0, base + 0x4); /* for ISI4608 cards */

    board->status |= FIRMWARE_LOADED;
    retval = 0;

errrelfw:
    release_firmware(fw);
end:
    return retval;
}

/*
 *  Insmod can set static symbols so keep these static
 */
static unsigned int card_count;

static int __devinit isicom_probe(struct pci_dev *pdev,
    const struct pci_device_id *ent)
{
    unsigned int uninitialized_var(signature), index;
    int retval = -EPERM;
    struct isi_board *board = NULL;

    if (card_count >= BOARD_COUNT)
        goto err;

    retval = pci_enable_device(pdev);
    if (retval) {
        dev_err(&pdev->dev, "failed to enable\n");
        goto err;
    }

    dev_info(&pdev->dev, "ISI PCI Card(Device ID 0x%x)\n", ent->device);

    /* allot the first empty slot in the array */
    for (index = 0; index < BOARD_COUNT; index++) {
        if (isi_card[index].base == 0) {
            board = &isi_card[index];
            break;
        }
    }
    if (index == BOARD_COUNT) {
        retval = -ENODEV;
        goto err_disable;
    }

    board->index = index;
    board->base = pci_resource_start(pdev, 3);
    board->irq = pdev->irq;
    card_count++;

    pci_set_drvdata(pdev, board);

    retval = pci_request_region(pdev, 3, ISICOM_NAME);
    if (retval) {
        dev_err(&pdev->dev, "I/O Region 0x%lx-0x%lx is busy. Card%d "
            "will be disabled.\n", board->base, board->base + 15,
            index + 1);
        retval = -EBUSY;
        goto errdec;
    }

    retval = request_irq(board->irq, isicom_interrupt,
            IRQF_SHARED, ISICOM_NAME, board);
    if (retval < 0) {
        dev_err(&pdev->dev, "Could not install handler at Irq %d. "
            "Card%d will be disabled.\n", board->irq, index + 1);
        goto errunrr;
    }

    retval = reset_card(pdev, index, &signature);
    if (retval < 0)
        goto errunri;

    retval = load_firmware(pdev, index, signature);
    if (retval < 0)
        goto errunri;

    for (index = 0; index < board->port_count; index++)
        tty_port_register_device(&board->ports[index].port,
                isicom_normal, board->index * 16 + index,
                &pdev->dev);

    return 0;

errunri:
    free_irq(board->irq, board);
errunrr:
    pci_release_region(pdev, 3);
errdec:
    board->base = 0;
    card_count--;
err_disable:
    pci_disable_device(pdev);
err:
    return retval;
}

static void __devexit isicom_remove(struct pci_dev *pdev)
{
    struct isi_board *board = pci_get_drvdata(pdev);
    unsigned int i;

    for (i = 0; i < board->port_count; i++)
        tty_unregister_device(isicom_normal, board->index * 16 + i);

    free_irq(board->irq, board);
    pci_release_region(pdev, 3);
    board->base = 0;
    card_count--;
    pci_disable_device(pdev);
}

static int __init isicom_init(void)
{
    int retval, idx, channel;
    struct isi_port *port;

    for (idx = 0; idx < BOARD_COUNT; idx++) {
        port = &isi_ports[idx * 16];
        isi_card[idx].ports = port;
        spin_lock_init(&isi_card[idx].card_lock);
        for (channel = 0; channel < 16; channel++, port++) {
            tty_port_init(&port->port);
            port->port.ops = &isicom_port_ops;
            port->magic = ISICOM_MAGIC;
            port->card = &isi_card[idx];
            port->channel = channel;
            port->port.close_delay = 50 * HZ/100;
            port->port.closing_wait = 3000 * HZ/100;
            port->status = 0;
            /*  . . .  */
        }
        isi_card[idx].base = 0;
        isi_card[idx].irq = 0;
    }

    /* tty driver structure initialization */
    isicom_normal = alloc_tty_driver(PORT_COUNT);
    if (!isicom_normal) {
        retval = -ENOMEM;
        goto error;
    }

    isicom_normal->name             = "ttyM";
    isicom_normal->major            = ISICOM_NMAJOR;
    isicom_normal->minor_start      = 0;
    isicom_normal->type         = TTY_DRIVER_TYPE_SERIAL;
    isicom_normal->subtype          = SERIAL_TYPE_NORMAL;
    isicom_normal->init_termios     = tty_std_termios;
    isicom_normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
        CLOCAL;
    isicom_normal->flags            = TTY_DRIVER_REAL_RAW |
        TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_HARDWARE_BREAK;
    tty_set_operations(isicom_normal, &isicom_ops);

    retval = tty_register_driver(isicom_normal);
    if (retval) {
        pr_debug("Couldn't register the dialin driver\n");
        goto err_puttty;
    }

    retval = pci_register_driver(&isicom_driver);
    if (retval < 0) {
        pr_err("Unable to register pci driver.\n");
        goto err_unrtty;
    }

    mod_timer(&tx, jiffies + 1);

    return 0;
err_unrtty:
    tty_unregister_driver(isicom_normal);
err_puttty:
    put_tty_driver(isicom_normal);
error:
    return retval;
}

static void __exit isicom_exit(void)
{
    del_timer_sync(&tx);

    pci_unregister_driver(&isicom_driver);
    tty_unregister_driver(isicom_normal);
    put_tty_driver(isicom_normal);
}

module_init(isicom_init);
module_exit(isicom_exit);

MODULE_AUTHOR("MultiTech");
MODULE_DESCRIPTION("Driver for the ISI series of cards by MultiTech");
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("isi608.bin");
MODULE_FIRMWARE("isi608em.bin");
MODULE_FIRMWARE("isi616em.bin");
MODULE_FIRMWARE("isi4608.bin");
MODULE_FIRMWARE("isi4616.bin");