module.c

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/* $Id: module.c,v 1.14.6.4 2001/09/23 22:24:32 kai Exp $
 *
 * ISDN lowlevel-module for the IBM ISDN-S0 Active 2000.
 *
 * Author       Fritz Elfert
 * Copyright    by Fritz Elfert      <[email protected]>
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 * Thanks to Friedemann Baitinger and IBM Germany
 *
 */

#include "act2000.h"
#include "act2000_isa.h"
#include "capi.h"
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>

static unsigned short act2000_isa_ports[] =
{
    0x0200, 0x0240, 0x0280, 0x02c0, 0x0300, 0x0340, 0x0380,
    0xcfe0, 0xcfa0, 0xcf60, 0xcf20, 0xcee0, 0xcea0, 0xce60,
};

static act2000_card *cards = (act2000_card *) NULL;

/* Parameters to be set by insmod */
static int   act_bus  =  0;
static int   act_port = -1;  /* -1 = Autoprobe  */
static int   act_irq  = -1;
static char *act_id   = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";

MODULE_DESCRIPTION("ISDN4Linux: Driver for IBM Active 2000 ISDN card");
MODULE_AUTHOR("Fritz Elfert");
MODULE_LICENSE("GPL");
MODULE_PARM_DESC(act_bus, "BusType of first card, 1=ISA, 2=MCA, 3=PCMCIA, currently only ISA");
MODULE_PARM_DESC(membase, "Base port address of first card");
MODULE_PARM_DESC(act_irq, "IRQ of first card");
MODULE_PARM_DESC(act_id, "ID-String of first card");
module_param(act_bus, int, 0);
module_param(act_port, int, 0);
module_param(act_irq, int, 0);
module_param(act_id, charp, 0);

static int act2000_addcard(int, int, int, char *);

static act2000_chan *
find_channel(act2000_card *card, int channel)
{
    if ((channel >= 0) && (channel < ACT2000_BCH))
        return &(card->bch[channel]);
    printk(KERN_WARNING "act2000: Invalid channel %d\n", channel);
    return NULL;
}

/*
 * Free MSN list
 */
static void
act2000_clear_msn(act2000_card *card)
{
    struct msn_entry *p = card->msn_list;
    struct msn_entry *q;
    unsigned long flags;

    spin_lock_irqsave(&card->lock, flags);
    card->msn_list = NULL;
    spin_unlock_irqrestore(&card->lock, flags);
    while (p) {
        q  = p->next;
        kfree(p);
        p = q;
    }
}

/*
 * Find an MSN entry in the list.
 * If ia5 != 0, return IA5-encoded EAZ, else
 * return a bitmask with corresponding bit set.
 */
static __u16
act2000_find_msn(act2000_card *card, char *msn, int ia5)
{
    struct msn_entry *p = card->msn_list;
    __u8 eaz = '0';

    while (p) {
        if (!strcmp(p->msn, msn)) {
            eaz = p->eaz;
            break;
        }
        p = p->next;
    }
    if (!ia5)
        return (1 << (eaz - '0'));
    else
        return eaz;
}

/*
 * Find an EAZ entry in the list.
 * return a string with corresponding msn.
 */
char *
act2000_find_eaz(act2000_card *card, char eaz)
{
    struct msn_entry *p = card->msn_list;

    while (p) {
        if (p->eaz == eaz)
            return (p->msn);
        p = p->next;
    }
    return ("\0");
}

/*
 * Add or delete an MSN to the MSN list
 *
 * First character of msneaz is EAZ, rest is MSN.
 * If length of eazmsn is 1, delete that entry.
 */
static int
act2000_set_msn(act2000_card *card, char *eazmsn)
{
    struct msn_entry *p = card->msn_list;
    struct msn_entry *q = NULL;
    unsigned long flags;
    int i;

    if (!strlen(eazmsn))
        return 0;
    if (strlen(eazmsn) > 16)
        return -EINVAL;
    for (i = 0; i < strlen(eazmsn); i++)
        if (!isdigit(eazmsn[i]))
            return -EINVAL;
    if (strlen(eazmsn) == 1) {
        /* Delete a single MSN */
        while (p) {
            if (p->eaz == eazmsn[0]) {
                spin_lock_irqsave(&card->lock, flags);
                if (q)
                    q->next = p->next;
                else
                    card->msn_list = p->next;
                spin_unlock_irqrestore(&card->lock, flags);
                kfree(p);
                printk(KERN_DEBUG
                       "Mapping for EAZ %c deleted\n",
                       eazmsn[0]);
                return 0;
            }
            q = p;
            p = p->next;
        }
        return 0;
    }
    /* Add a single MSN */
    while (p) {
        /* Found in list, replace MSN */
        if (p->eaz == eazmsn[0]) {
            spin_lock_irqsave(&card->lock, flags);
            strcpy(p->msn, &eazmsn[1]);
            spin_unlock_irqrestore(&card->lock, flags);
            printk(KERN_DEBUG
                   "Mapping for EAZ %c changed to %s\n",
                   eazmsn[0],
                   &eazmsn[1]);
            return 0;
        }
        p = p->next;
    }
    /* Not found in list, add new entry */
    p = kmalloc(sizeof(msn_entry), GFP_KERNEL);
    if (!p)
        return -ENOMEM;
    p->eaz = eazmsn[0];
    strcpy(p->msn, &eazmsn[1]);
    p->next = card->msn_list;
    spin_lock_irqsave(&card->lock, flags);
    card->msn_list = p;
    spin_unlock_irqrestore(&card->lock, flags);
    printk(KERN_DEBUG
           "Mapping %c -> %s added\n",
           eazmsn[0],
           &eazmsn[1]);
    return 0;
}

static void
act2000_transmit(struct work_struct *work)
{
    struct act2000_card *card =
        container_of(work, struct act2000_card, snd_tq);

    switch (card->bus) {
    case ACT2000_BUS_ISA:
        act2000_isa_send(card);
        break;
    case ACT2000_BUS_PCMCIA:
    case ACT2000_BUS_MCA:
    default:
        printk(KERN_WARNING
               "act2000_transmit: Illegal bustype %d\n", card->bus);
    }
}

static void
act2000_receive(struct work_struct *work)
{
    struct act2000_card *card =
        container_of(work, struct act2000_card, poll_tq);

    switch (card->bus) {
    case ACT2000_BUS_ISA:
        act2000_isa_receive(card);
        break;
    case ACT2000_BUS_PCMCIA:
    case ACT2000_BUS_MCA:
    default:
        printk(KERN_WARNING
               "act2000_receive: Illegal bustype %d\n", card->bus);
    }
}

static void
act2000_poll(unsigned long data)
{
    act2000_card *card = (act2000_card *)data;
    unsigned long flags;

    act2000_receive(&card->poll_tq);
    spin_lock_irqsave(&card->lock, flags);
    mod_timer(&card->ptimer, jiffies + 3);
    spin_unlock_irqrestore(&card->lock, flags);
}

static int
act2000_command(act2000_card *card, isdn_ctrl *c)
{
    ulong a;
    act2000_chan *chan;
    act2000_cdef cdef;
    isdn_ctrl cmd;
    char tmp[17];
    int ret;
    unsigned long flags;
    void __user *arg;

    switch (c->command) {
    case ISDN_CMD_IOCTL:
        memcpy(&a, c->parm.num, sizeof(ulong));
        arg = (void __user *)a;
        switch (c->arg) {
        case ACT2000_IOCTL_LOADBOOT:
            switch (card->bus) {
            case ACT2000_BUS_ISA:
                ret = act2000_isa_download(card,
                               arg);
                if (!ret) {
                    card->flags |= ACT2000_FLAGS_LOADED;
                    if (!(card->flags & ACT2000_FLAGS_IVALID)) {
                        card->ptimer.expires = jiffies + 3;
                        card->ptimer.function = act2000_poll;
                        card->ptimer.data = (unsigned long)card;
                        add_timer(&card->ptimer);
                    }
                    actcapi_manufacturer_req_errh(card);
                }
                break;
            default:
                printk(KERN_WARNING
                       "act2000: Illegal BUS type %d\n",
                       card->bus);
                ret = -EIO;
            }
            return ret;
        case ACT2000_IOCTL_SETPROTO:
            card->ptype = a ? ISDN_PTYPE_EURO : ISDN_PTYPE_1TR6;
            if (!(card->flags & ACT2000_FLAGS_RUNNING))
                return 0;
            actcapi_manufacturer_req_net(card);
            return 0;
        case ACT2000_IOCTL_SETMSN:
            if (copy_from_user(tmp, arg,
                       sizeof(tmp)))
                return -EFAULT;
            if ((ret = act2000_set_msn(card, tmp)))
                return ret;
            if (card->flags & ACT2000_FLAGS_RUNNING)
                return (actcapi_manufacturer_req_msn(card));
            return 0;
        case ACT2000_IOCTL_ADDCARD:
            if (copy_from_user(&cdef, arg,
                       sizeof(cdef)))
                return -EFAULT;
            if (act2000_addcard(cdef.bus, cdef.port, cdef.irq, cdef.id))
                return -EIO;
            return 0;
        case ACT2000_IOCTL_TEST:
            if (!(card->flags & ACT2000_FLAGS_RUNNING))
                return -ENODEV;
            return 0;
        default:
            return -EINVAL;
        }
        break;
    case ISDN_CMD_DIAL:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        spin_lock_irqsave(&card->lock, flags);
        if (chan->fsm_state != ACT2000_STATE_NULL) {
            spin_unlock_irqrestore(&card->lock, flags);
            printk(KERN_WARNING "Dial on channel with state %d\n",
                   chan->fsm_state);
            return -EBUSY;
        }
        if (card->ptype == ISDN_PTYPE_EURO)
            tmp[0] = act2000_find_msn(card, c->parm.setup.eazmsn, 1);
        else
            tmp[0] = c->parm.setup.eazmsn[0];
        chan->fsm_state = ACT2000_STATE_OCALL;
        chan->callref = 0xffff;
        spin_unlock_irqrestore(&card->lock, flags);
        ret = actcapi_connect_req(card, chan, c->parm.setup.phone,
                      tmp[0], c->parm.setup.si1,
                      c->parm.setup.si2);
        if (ret) {
            cmd.driver = card->myid;
            cmd.command = ISDN_STAT_DHUP;
            cmd.arg &= 0x0f;
            card->interface.statcallb(&cmd);
        }
        return ret;
    case ISDN_CMD_ACCEPTD:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        if (chan->fsm_state == ACT2000_STATE_ICALL)
            actcapi_select_b2_protocol_req(card, chan);
        return 0;
    case ISDN_CMD_ACCEPTB:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        return 0;
    case ISDN_CMD_HANGUP:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        switch (chan->fsm_state) {
        case ACT2000_STATE_ICALL:
        case ACT2000_STATE_BSETUP:
            actcapi_connect_resp(card, chan, 0x15);
            break;
        case ACT2000_STATE_ACTIVE:
            actcapi_disconnect_b3_req(card, chan);
            break;
        }
        return 0;
    case ISDN_CMD_SETEAZ:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        if (strlen(c->parm.num)) {
            if (card->ptype == ISDN_PTYPE_EURO) {
                chan->eazmask = act2000_find_msn(card, c->parm.num, 0);
            }
            if (card->ptype == ISDN_PTYPE_1TR6) {
                int i;
                chan->eazmask = 0;
                for (i = 0; i < strlen(c->parm.num); i++)
                    if (isdigit(c->parm.num[i]))
                        chan->eazmask |= (1 << (c->parm.num[i] - '0'));
            }
        } else
            chan->eazmask = 0x3ff;
        actcapi_listen_req(card);
        return 0;
    case ISDN_CMD_CLREAZ:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        chan->eazmask = 0;
        actcapi_listen_req(card);
        return 0;
    case ISDN_CMD_SETL2:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        chan->l2prot = (c->arg >> 8);
        return 0;
    case ISDN_CMD_SETL3:
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        if ((c->arg >> 8) != ISDN_PROTO_L3_TRANS) {
            printk(KERN_WARNING "L3 protocol unknown\n");
            return -1;
        }
        if (!(chan = find_channel(card, c->arg & 0x0f)))
            break;
        chan->l3prot = (c->arg >> 8);
        return 0;
    }

    return -EINVAL;
}

static int
act2000_sendbuf(act2000_card *card, int channel, int ack, struct sk_buff *skb)
{
    struct sk_buff *xmit_skb;
    int len;
    act2000_chan *chan;
    actcapi_msg *msg;

    if (!(chan = find_channel(card, channel)))
        return -1;
    if (chan->fsm_state != ACT2000_STATE_ACTIVE)
        return -1;
    len = skb->len;
    if ((chan->queued + len) >= ACT2000_MAX_QUEUED)
        return 0;
    if (!len)
        return 0;
    if (skb_headroom(skb) < 19) {
        printk(KERN_WARNING "act2000_sendbuf: Headroom only %d\n",
               skb_headroom(skb));
        xmit_skb = alloc_skb(len + 19, GFP_ATOMIC);
        if (!xmit_skb) {
            printk(KERN_WARNING "act2000_sendbuf: Out of memory\n");
            return 0;
        }
        skb_reserve(xmit_skb, 19);
        skb_copy_from_linear_data(skb, skb_put(xmit_skb, len), len);
    } else {
        xmit_skb = skb_clone(skb, GFP_ATOMIC);
        if (!xmit_skb) {
            printk(KERN_WARNING "act2000_sendbuf: Out of memory\n");
            return 0;
        }
    }
    dev_kfree_skb(skb);
    msg = (actcapi_msg *)skb_push(xmit_skb, 19);
    msg->hdr.len = 19 + len;
    msg->hdr.applicationID = 1;
    msg->hdr.cmd.cmd = 0x86;
    msg->hdr.cmd.subcmd = 0x00;
    msg->hdr.msgnum = actcapi_nextsmsg(card);
    msg->msg.data_b3_req.datalen = len;
    msg->msg.data_b3_req.blocknr = (msg->hdr.msgnum & 0xff);
    msg->msg.data_b3_req.fakencci = MAKE_NCCI(chan->plci, 0, chan->ncci);
    msg->msg.data_b3_req.flags = ack; /* Will be set to 0 on actual sending */
    actcapi_debug_msg(xmit_skb, 1);
    chan->queued += len;
    skb_queue_tail(&card->sndq, xmit_skb);
    act2000_schedule_tx(card);
    return len;
}


/* Read the Status-replies from the Interface */
static int
act2000_readstatus(u_char __user *buf, int len, act2000_card *card)
{
    int count;
    u_char __user *p;

    for (p = buf, count = 0; count < len; p++, count++) {
        if (card->status_buf_read == card->status_buf_write)
            return count;
        put_user(*card->status_buf_read++, p);
        if (card->status_buf_read > card->status_buf_end)
            card->status_buf_read = card->status_buf;
    }
    return count;
}

/*
 * Find card with given driverId
 */
static inline act2000_card *
act2000_findcard(int driverid)
{
    act2000_card *p = cards;

    while (p) {
        if (p->myid == driverid)
            return p;
        p = p->next;
    }
    return (act2000_card *) 0;
}

/*
 * Wrapper functions for interface to linklevel
 */
static int
if_command(isdn_ctrl *c)
{
    act2000_card *card = act2000_findcard(c->driver);

    if (card)
        return (act2000_command(card, c));
    printk(KERN_ERR
           "act2000: if_command %d called with invalid driverId %d!\n",
           c->command, c->driver);
    return -ENODEV;
}

static int
if_writecmd(const u_char __user *buf, int len, int id, int channel)
{
    act2000_card *card = act2000_findcard(id);

    if (card) {
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        return (len);
    }
    printk(KERN_ERR
           "act2000: if_writecmd called with invalid driverId!\n");
    return -ENODEV;
}

static int
if_readstatus(u_char __user *buf, int len, int id, int channel)
{
    act2000_card *card = act2000_findcard(id);

    if (card) {
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        return (act2000_readstatus(buf, len, card));
    }
    printk(KERN_ERR
           "act2000: if_readstatus called with invalid driverId!\n");
    return -ENODEV;
}

static int
if_sendbuf(int id, int channel, int ack, struct sk_buff *skb)
{
    act2000_card *card = act2000_findcard(id);

    if (card) {
        if (!(card->flags & ACT2000_FLAGS_RUNNING))
            return -ENODEV;
        return (act2000_sendbuf(card, channel, ack, skb));
    }
    printk(KERN_ERR
           "act2000: if_sendbuf called with invalid driverId!\n");
    return -ENODEV;
}


/*
 * Allocate a new card-struct, initialize it
 * link it into cards-list.
 */
static void
act2000_alloccard(int bus, int port, int irq, char *id)
{
    int i;
    act2000_card *card;
    if (!(card = kzalloc(sizeof(act2000_card), GFP_KERNEL))) {
        printk(KERN_WARNING
               "act2000: (%s) Could not allocate card-struct.\n", id);
        return;
    }
    spin_lock_init(&card->lock);
    spin_lock_init(&card->mnlock);
    skb_queue_head_init(&card->sndq);
    skb_queue_head_init(&card->rcvq);
    skb_queue_head_init(&card->ackq);
    INIT_WORK(&card->snd_tq, act2000_transmit);
    INIT_WORK(&card->rcv_tq, actcapi_dispatch);
    INIT_WORK(&card->poll_tq, act2000_receive);
    init_timer(&card->ptimer);
    card->interface.owner = THIS_MODULE;
    card->interface.channels = ACT2000_BCH;
    card->interface.maxbufsize = 4000;
    card->interface.command = if_command;
    card->interface.writebuf_skb = if_sendbuf;
    card->interface.writecmd = if_writecmd;
    card->interface.readstat = if_readstatus;
    card->interface.features =
        ISDN_FEATURE_L2_X75I |
        ISDN_FEATURE_L2_HDLC |
        ISDN_FEATURE_L3_TRANS |
        ISDN_FEATURE_P_UNKNOWN;
    card->interface.hl_hdrlen = 20;
    card->ptype = ISDN_PTYPE_EURO;
    strlcpy(card->interface.id, id, sizeof(card->interface.id));
    for (i = 0; i < ACT2000_BCH; i++) {
        card->bch[i].plci = 0x8000;
        card->bch[i].ncci = 0x8000;
        card->bch[i].l2prot = ISDN_PROTO_L2_X75I;
        card->bch[i].l3prot = ISDN_PROTO_L3_TRANS;
    }
    card->myid = -1;
    card->bus = bus;
    card->port = port;
    card->irq = irq;
    card->next = cards;
    cards = card;
}

/*
 * register card at linklevel
 */
static int
act2000_registercard(act2000_card *card)
{
    switch (card->bus) {
    case ACT2000_BUS_ISA:
        break;
    case ACT2000_BUS_MCA:
    case ACT2000_BUS_PCMCIA:
    default:
        printk(KERN_WARNING
               "act2000: Illegal BUS type %d\n",
               card->bus);
        return -1;
    }
    if (!register_isdn(&card->interface)) {
        printk(KERN_WARNING
               "act2000: Unable to register %s\n",
               card->interface.id);
        return -1;
    }
    card->myid = card->interface.channels;
    sprintf(card->regname, "act2000-isdn (%s)", card->interface.id);
    return 0;
}

static void
unregister_card(act2000_card *card)
{
    isdn_ctrl cmd;

    cmd.command = ISDN_STAT_UNLOAD;
    cmd.driver = card->myid;
    card->interface.statcallb(&cmd);
    switch (card->bus) {
    case ACT2000_BUS_ISA:
        act2000_isa_release(card);
        break;
    case ACT2000_BUS_MCA:
    case ACT2000_BUS_PCMCIA:
    default:
        printk(KERN_WARNING
               "act2000: Invalid BUS type %d\n",
               card->bus);
        break;
    }
}

static int
act2000_addcard(int bus, int port, int irq, char *id)
{
    act2000_card *p;
    act2000_card *q = NULL;
    int initialized;
    int added = 0;
    int failed = 0;
    int i;

    if (!bus)
        bus = ACT2000_BUS_ISA;
    if (port != -1) {
        /* Port defined, do fixed setup */
        act2000_alloccard(bus, port, irq, id);
    } else {
        /* No port defined, perform autoprobing.
         * This may result in more than one card detected.
         */
        switch (bus) {
        case ACT2000_BUS_ISA:
            for (i = 0; i < ARRAY_SIZE(act2000_isa_ports); i++)
                if (act2000_isa_detect(act2000_isa_ports[i])) {
                    printk(KERN_INFO "act2000: Detected "
                           "ISA card at port 0x%x\n",
                           act2000_isa_ports[i]);
                    act2000_alloccard(bus,
                              act2000_isa_ports[i], irq, id);
                }
            break;
        case ACT2000_BUS_MCA:
        case ACT2000_BUS_PCMCIA:
        default:
            printk(KERN_WARNING
                   "act2000: addcard: Invalid BUS type %d\n", bus);
        }
    }
    if (!cards)
        return 1;
    p = cards;
    while (p) {
        initialized = 0;
        if (!p->interface.statcallb) {
            /* Not yet registered.
             * Try to register and activate it.
             */
            added++;
            switch (p->bus) {
            case ACT2000_BUS_ISA:
                if (act2000_isa_detect(p->port)) {
                    if (act2000_registercard(p))
                        break;
                    if (act2000_isa_config_port(p, p->port)) {
                        printk(KERN_WARNING
                               "act2000: Could not request port 0x%04x\n",
                               p->port);
                        unregister_card(p);
                        p->interface.statcallb = NULL;
                        break;
                    }
                    if (act2000_isa_config_irq(p, p->irq)) {
                        printk(KERN_INFO
                               "act2000: No IRQ available, fallback to polling\n");
                        /* Fall back to polled operation */
                        p->irq = 0;
                    }
                    printk(KERN_INFO
                           "act2000: ISA"
                           "-type card at port "
                           "0x%04x ",
                           p->port);
                    if (p->irq)
                        printk("irq %d\n", p->irq);
                    else
                        printk("polled\n");
                    initialized = 1;
                }
                break;
            case ACT2000_BUS_MCA:
            case ACT2000_BUS_PCMCIA:
            default:
                printk(KERN_WARNING
                       "act2000: addcard: Invalid BUS type %d\n",
                       p->bus);
            }
        } else
            /* Card already initialized */
            initialized = 1;
        if (initialized) {
            /* Init OK, next card ... */
            q = p;
            p = p->next;
        } else {
            /* Init failed, remove card from list, free memory */
            printk(KERN_WARNING
                   "act2000: Initialization of %s failed\n",
                   p->interface.id);
            if (q) {
                q->next = p->next;
                kfree(p);
                p = q->next;
            } else {
                cards = p->next;
                kfree(p);
                p = cards;
            }
            failed++;
        }
    }
    return (added - failed);
}

#define DRIVERNAME "IBM Active 2000 ISDN driver"

static int __init act2000_init(void)
{
    printk(KERN_INFO "%s\n", DRIVERNAME);
    if (!cards)
        act2000_addcard(act_bus, act_port, act_irq, act_id);
    if (!cards)
        printk(KERN_INFO "act2000: No cards defined yet\n");
    return 0;
}

static void __exit act2000_exit(void)
{
    act2000_card *card = cards;
    act2000_card *last;
    while (card) {
        unregister_card(card);
        del_timer(&card->ptimer);
        card = card->next;
    }
    card = cards;
    while (card) {
        last = card;
        card = card->next;
        act2000_clear_msn(last);
        kfree(last);
    }
    printk(KERN_INFO "%s unloaded\n", DRIVERNAME);
}

module_init(act2000_init);
module_exit(act2000_exit);