// SPDX-License-Identifier: GPL-2.0+
/*
 *      Original driver code supplied by Multi-Tech
 *
 *      Changes
 *      1/9/98  alan@lxorguk.ukuu.org.uk
 *                                      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 alan@lxorguk.ukuu.org.uk
 *                                      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 acme@conectiva.com.br  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 isicom_remove(struct pci_dev *);

static const 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         = isicom_remove
};

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

static void isicom_tx(struct timer_list *unused);
static void isicom_start(struct tty_struct *tty);

static DEFINE_TIMER(tx, isicom_tx);

/*   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 int WaitTillCardIsFree(unsigned long base)
{
        unsigned int count = 0;

        while (!(inw(base + 0xe) & 0x1) && count++ < 100)
                mdelay(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_warn("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 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_warn("Warning: bad isicom magic for dev %s in %s\n",
                        name, routine);
                return 1;
        }
        if (port->magic != ISICOM_MAGIC) {
                pr_warn("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(struct timer_list *unused)
{
        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 (!tty_port_initialized(&port->port) ||
                        !(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_warn("%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 (!tty_port_initialized(&port->port)) {
                outw(0x0000, base+0x04); /* enable interrupts */
                spin_unlock(&card->card_lock);
                return IRQ_HANDLED;
        }

        tty = tty_port_tty_get(&port->port);
        if (tty == NULL) {
                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 (tty_port_check_carrier(&port->port)) {
                                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) {
                                                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(&port->port, 0, TTY_BREAK);
                        if (port->port.flags & ASYNC_SAK)
                                do_SAK(tty);
                        tty_flip_buffer_push(&port->port);
                        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(&port->port, &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(&port->port, 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(&port->port);
        }
        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);
        }
        tty_port_set_check_carrier(&port->port, !C_CLOCAL(tty));

        /* flow control settings ...*/
        flow_ctrl = 0;
        tty_port_set_cts_flow(&port->port, C_CRTSCTS(tty));
        if (C_CRTSCTS(tty))
                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 & 0xff00u), 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 *ss)
{
        struct isi_port *port = tty->driver_data;
        int reconfig_port;

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

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

        if (!capable(CAP_SYS_ADMIN)) {
                if ((ss->close_delay != port->port.close_delay) ||
                                (ss->closing_wait != port->port.closing_wait) ||
                                ((ss->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) |
                                (ss->flags & ASYNC_USR_MASK));
        } else {
                port->port.close_delay = ss->close_delay;
                port->port.closing_wait = ss->closing_wait;
                port->port.flags = ((port->port.flags & ~ASYNC_FLAGS) |
                                (ss->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 tty_struct *tty,
        struct serial_struct *ss)
{
        struct isi_port *port = tty->driver_data;

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

        mutex_lock(&port->port.mutex);
/*      ss->type = ? */
        ss->line = port - isi_ports;
        ss->port = port->card->base;
        ss->irq = port->card->irq;
        ss->flags = port->port.flags;
/*      ss->baud_base = ? */
        ss->close_delay = port->port.close_delay;
        ss->closing_wait = port->port.closing_wait;
        mutex_unlock(&port->port.mutex);
        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) && !C_CRTSCTS(tty)) {
                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,
        .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,
        .get_serial             = isicom_get_serial_info,
        .set_serial             = isicom_set_serial_info,
};

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 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 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_array(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 isicom_probe(struct pci_dev *pdev,
        const struct pci_device_id *ent)
{
        unsigned int 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++) {
                struct tty_port *tport = &board->ports[index].port;
                tty_port_init(tport);
                tport->ops = &isicom_port_ops;
                tport->close_delay = 50 * HZ/100;
                tport->closing_wait = 3000 * HZ/100;
                tty_port_register_device(tport, 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 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);
                tty_port_destroy(&board->ports[i].port);
        }

        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++) {
                        port->magic = ISICOM_MAGIC;
                        port->card = &isi_card[idx];
                        port->channel = channel;
                        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");