/*
 * Linux ISDN subsystem, tty functions and AT-command emulator (linklevel).
 *
 * Copyright 1994-1999  by Fritz Elfert (fritz@isdn4linux.de)
 * Copyright 1995,96    by Thinking Objects Software GmbH Wuerzburg
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */
#undef ISDN_TTY_STAT_DEBUG

#include <linux/isdn.h>
#include <linux/serial.h> /* ASYNC_* flags */
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include "isdn_common.h"
#include "isdn_tty.h"
#ifdef CONFIG_ISDN_AUDIO
#include "isdn_audio.h"
#define VBUF 0x3e0
#define VBUFX (VBUF/16)
#endif

#define FIX_FILE_TRANSFER
#define DUMMY_HAYES_AT

/* Prototypes */

static DEFINE_MUTEX(modem_info_mutex);
static int isdn_tty_edit_at(const char *, int, modem_info *);
static void isdn_tty_check_esc(const u_char *, u_char, int, int *, u_long *);
static void isdn_tty_modem_reset_regs(modem_info *, int);
static void isdn_tty_cmd_ATA(modem_info *);
static void isdn_tty_flush_buffer(struct tty_struct *);
static void isdn_tty_modem_result(int, modem_info *);
#ifdef CONFIG_ISDN_AUDIO
static int isdn_tty_countDLE(unsigned char *, int);
#endif

/* Leave this unchanged unless you know what you do! */
#define MODEM_PARANOIA_CHECK
#define MODEM_DO_RESTART

static int bit2si[8] =
{1, 5, 7, 7, 7, 7, 7, 7};
static int si2bit[8] =
{4, 1, 4, 4, 4, 4, 4, 4};

/* isdn_tty_try_read() is called from within isdn_tty_rcv_skb()
 * to stuff incoming data directly into a tty's flip-buffer. This
 * is done to speed up tty-receiving if the receive-queue is empty.
 * This routine MUST be called with interrupts off.
 * Return:
 *  1 = Success
 *  0 = Failure, data has to be buffered and later processed by
 *      isdn_tty_readmodem().
 */
static int
isdn_tty_try_read(modem_info *info, struct sk_buff *skb)
{
        struct tty_port *port = &info->port;
        int c;
        int len;
        char last;

        if (!info->online)
                return 0;

        if (!(info->mcr & UART_MCR_RTS))
                return 0;

        len = skb->len
#ifdef CONFIG_ISDN_AUDIO
                + ISDN_AUDIO_SKB_DLECOUNT(skb)
#endif
                ;

        c = tty_buffer_request_room(port, len);
        if (c < len)
                return 0;

#ifdef CONFIG_ISDN_AUDIO
        if (ISDN_AUDIO_SKB_DLECOUNT(skb)) {
                int l = skb->len;
                unsigned char *dp = skb->data;
                while (--l) {
                        if (*dp == DLE)
                                tty_insert_flip_char(port, DLE, 0);
                        tty_insert_flip_char(port, *dp++, 0);
                }
                if (*dp == DLE)
                        tty_insert_flip_char(port, DLE, 0);
                last = *dp;
        } else {
#endif
                if (len > 1)
                        tty_insert_flip_string(port, skb->data, len - 1);
                last = skb->data[len - 1];
#ifdef CONFIG_ISDN_AUDIO
        }
#endif
        if (info->emu.mdmreg[REG_CPPP] & BIT_CPPP)
                tty_insert_flip_char(port, last, 0xFF);
        else
                tty_insert_flip_char(port, last, TTY_NORMAL);
        tty_flip_buffer_push(port);
        kfree_skb(skb);

        return 1;
}

/* isdn_tty_readmodem() is called periodically from within timer-interrupt.
 * It tries getting received data from the receive queue an stuff it into
 * the tty's flip-buffer.
 */
void
isdn_tty_readmodem(void)
{
        int resched = 0;
        int midx;
        int i;
        int r;
        modem_info *info;

        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                midx = dev->m_idx[i];
                if (midx < 0)
                        continue;

                info = &dev->mdm.info[midx];
                if (!info->online)
                        continue;

                r = 0;
#ifdef CONFIG_ISDN_AUDIO
                isdn_audio_eval_dtmf(info);
                if ((info->vonline & 1) && (info->emu.vpar[1]))
                        isdn_audio_eval_silence(info);
#endif
                if (info->mcr & UART_MCR_RTS) {
                        /* CISCO AsyncPPP Hack */
                        if (!(info->emu.mdmreg[REG_CPPP] & BIT_CPPP))
                                r = isdn_readbchan_tty(info->isdn_driver,
                                                info->isdn_channel,
                                                &info->port, 0);
                        else
                                r = isdn_readbchan_tty(info->isdn_driver,
                                                info->isdn_channel,
                                                &info->port, 1);
                        if (r)
                                tty_flip_buffer_push(&info->port);
                } else
                        r = 1;

                if (r) {
                        info->rcvsched = 0;
                        resched = 1;
                } else
                        info->rcvsched = 1;
        }
        if (!resched)
                isdn_timer_ctrl(ISDN_TIMER_MODEMREAD, 0);
}

int
isdn_tty_rcv_skb(int i, int di, int channel, struct sk_buff *skb)
{
        ulong flags;
        int midx;
#ifdef CONFIG_ISDN_AUDIO
        int ifmt;
#endif
        modem_info *info;

        if ((midx = dev->m_idx[i]) < 0) {
                /* if midx is invalid, packet is not for tty */
                return 0;
        }
        info = &dev->mdm.info[midx];
#ifdef CONFIG_ISDN_AUDIO
        ifmt = 1;

        if ((info->vonline) && (!info->emu.vpar[4]))
                isdn_audio_calc_dtmf(info, skb->data, skb->len, ifmt);
        if ((info->vonline & 1) && (info->emu.vpar[1]))
                isdn_audio_calc_silence(info, skb->data, skb->len, ifmt);
#endif
        if ((info->online < 2)
#ifdef CONFIG_ISDN_AUDIO
            && (!(info->vonline & 1))
#endif
                ) {
                /* If Modem not listening, drop data */
                kfree_skb(skb);
                return 1;
        }
        if (info->emu.mdmreg[REG_T70] & BIT_T70) {
                if (info->emu.mdmreg[REG_T70] & BIT_T70_EXT) {
                        /* T.70 decoding: throw away the T.70 header (2 or 4 bytes)   */
                        if (skb->data[0] == 3) /* pure data packet -> 4 byte headers  */
                                skb_pull(skb, 4);
                        else
                                if (skb->data[0] == 1) /* keepalive packet -> 2 byte hdr  */
                                        skb_pull(skb, 2);
                } else
                        /* T.70 decoding: Simply throw away the T.70 header (4 bytes) */
                        if ((skb->data[0] == 1) && ((skb->data[1] == 0) || (skb->data[1] == 1)))
                                skb_pull(skb, 4);
        }
#ifdef CONFIG_ISDN_AUDIO
        ISDN_AUDIO_SKB_DLECOUNT(skb) = 0;
        ISDN_AUDIO_SKB_LOCK(skb) = 0;
        if (info->vonline & 1) {
                /* voice conversion/compression */
                switch (info->emu.vpar[3]) {
                case 2:
                case 3:
                case 4:
                        /* adpcm
                         * Since compressed data takes less
                         * space, we can overwrite the buffer.
                         */
                        skb_trim(skb, isdn_audio_xlaw2adpcm(info->adpcmr,
                                                            ifmt,
                                                            skb->data,
                                                            skb->data,
                                                            skb->len));
                        break;
                case 5:
                        /* a-law */
                        if (!ifmt)
                                isdn_audio_ulaw2alaw(skb->data, skb->len);
                        break;
                case 6:
                        /* u-law */
                        if (ifmt)
                                isdn_audio_alaw2ulaw(skb->data, skb->len);
                        break;
                }
                ISDN_AUDIO_SKB_DLECOUNT(skb) =
                        isdn_tty_countDLE(skb->data, skb->len);
        }
#ifdef CONFIG_ISDN_TTY_FAX
        else {
                if (info->faxonline & 2) {
                        isdn_tty_fax_bitorder(info, skb);
                        ISDN_AUDIO_SKB_DLECOUNT(skb) =
                                isdn_tty_countDLE(skb->data, skb->len);
                }
        }
#endif
#endif
        /* Try to deliver directly via tty-buf if queue is empty */
        spin_lock_irqsave(&info->readlock, flags);
        if (skb_queue_empty(&dev->drv[di]->rpqueue[channel]))
                if (isdn_tty_try_read(info, skb)) {
                        spin_unlock_irqrestore(&info->readlock, flags);
                        return 1;
                }
        /* Direct deliver failed or queue wasn't empty.
         * Queue up for later dequeueing via timer-irq.
         */
        __skb_queue_tail(&dev->drv[di]->rpqueue[channel], skb);
        dev->drv[di]->rcvcount[channel] +=
                (skb->len
#ifdef CONFIG_ISDN_AUDIO
                 + ISDN_AUDIO_SKB_DLECOUNT(skb)
#endif
                        );
        spin_unlock_irqrestore(&info->readlock, flags);
        /* Schedule dequeuing */
        if ((dev->modempoll) && (info->rcvsched))
                isdn_timer_ctrl(ISDN_TIMER_MODEMREAD, 1);
        return 1;
}

static void
isdn_tty_cleanup_xmit(modem_info *info)
{
        skb_queue_purge(&info->xmit_queue);
#ifdef CONFIG_ISDN_AUDIO
        skb_queue_purge(&info->dtmf_queue);
#endif
}

static void
isdn_tty_tint(modem_info *info)
{
        struct sk_buff *skb = skb_dequeue(&info->xmit_queue);
        int len, slen;

        if (!skb)
                return;
        len = skb->len;
        if ((slen = isdn_writebuf_skb_stub(info->isdn_driver,
                                           info->isdn_channel, 1, skb)) == len) {
                struct tty_struct *tty = info->port.tty;
                info->send_outstanding++;
                info->msr &= ~UART_MSR_CTS;
                info->lsr &= ~UART_LSR_TEMT;
                tty_wakeup(tty);
                return;
        }
        if (slen < 0) {
                /* Error: no channel, already shutdown, or wrong parameter */
                dev_kfree_skb(skb);
                return;
        }
        skb_queue_head(&info->xmit_queue, skb);
}

#ifdef CONFIG_ISDN_AUDIO
static int
isdn_tty_countDLE(unsigned char *buf, int len)
{
        int count = 0;

        while (len--)
                if (*buf++ == DLE)
                        count++;
        return count;
}

/* This routine is called from within isdn_tty_write() to perform
 * DLE-decoding when sending audio-data.
 */
static int
isdn_tty_handleDLEdown(modem_info *info, atemu *m, int len)
{
        unsigned char *p = &info->port.xmit_buf[info->xmit_count];
        int count = 0;

        while (len > 0) {
                if (m->lastDLE) {
                        m->lastDLE = 0;
                        switch (*p) {
                        case DLE:
                                /* Escape code */
                                if (len > 1)
                                        memmove(p, p + 1, len - 1);
                                p--;
                                count++;
                                break;
                        case ETX:
                                /* End of data */
                                info->vonline |= 4;
                                return count;
                        case DC4:
                                /* Abort RX */
                                info->vonline &= ~1;
#ifdef ISDN_DEBUG_MODEM_VOICE
                                printk(KERN_DEBUG
                                       "DLEdown: got DLE-DC4, send DLE-ETX on ttyI%d\n",
                                       info->line);
#endif
                                isdn_tty_at_cout("\020\003", info);
                                if (!info->vonline) {
#ifdef ISDN_DEBUG_MODEM_VOICE
                                        printk(KERN_DEBUG
                                               "DLEdown: send VCON on ttyI%d\n",
                                               info->line);
#endif
                                        isdn_tty_at_cout("\r\nVCON\r\n", info);
                                }
                                /* Fall through */
                        case 'q':
                        case 's':
                                /* Silence */
                                if (len > 1)
                                        memmove(p, p + 1, len - 1);
                                p--;
                                break;
                        }
                } else {
                        if (*p == DLE)
                                m->lastDLE = 1;
                        else
                                count++;
                }
                p++;
                len--;
        }
        if (len < 0) {
                printk(KERN_WARNING "isdn_tty: len<0 in DLEdown\n");
                return 0;
        }
        return count;
}

/* This routine is called from within isdn_tty_write() when receiving
 * audio-data. It interrupts receiving, if an character other than
 * ^S or ^Q is sent.
 */
static int
isdn_tty_end_vrx(const char *buf, int c)
{
        char ch;

        while (c--) {
                ch = *buf;
                if ((ch != 0x11) && (ch != 0x13))
                        return 1;
                buf++;
        }
        return 0;
}

static int voice_cf[7] =
{0, 0, 4, 3, 2, 0, 0};

#endif                          /* CONFIG_ISDN_AUDIO */

/* isdn_tty_senddown() is called either directly from within isdn_tty_write()
 * or via timer-interrupt from within isdn_tty_modem_xmit(). It pulls
 * outgoing data from the tty's xmit-buffer, handles voice-decompression or
 * T.70 if necessary, and finally queues it up for sending via isdn_tty_tint.
 */
static void
isdn_tty_senddown(modem_info *info)
{
        int buflen;
        int skb_res;
#ifdef CONFIG_ISDN_AUDIO
        int audio_len;
#endif
        struct sk_buff *skb;

#ifdef CONFIG_ISDN_AUDIO
        if (info->vonline & 4) {
                info->vonline &= ~6;
                if (!info->vonline) {
#ifdef ISDN_DEBUG_MODEM_VOICE
                        printk(KERN_DEBUG
                               "senddown: send VCON on ttyI%d\n",
                               info->line);
#endif
                        isdn_tty_at_cout("\r\nVCON\r\n", info);
                }
        }
#endif
        if (!(buflen = info->xmit_count))
                return;
        if ((info->emu.mdmreg[REG_CTS] & BIT_CTS) != 0)
                info->msr &= ~UART_MSR_CTS;
        info->lsr &= ~UART_LSR_TEMT;
        /* info->xmit_count is modified here and in isdn_tty_write().
         * So we return here if isdn_tty_write() is in the
         * critical section.
         */
        atomic_inc(&info->xmit_lock);
        if (!(atomic_dec_and_test(&info->xmit_lock)))
                return;
        if (info->isdn_driver < 0) {
                info->xmit_count = 0;
                return;
        }
        skb_res = dev->drv[info->isdn_driver]->interface->hl_hdrlen + 4;
#ifdef CONFIG_ISDN_AUDIO
        if (info->vonline & 2)
                audio_len = buflen * voice_cf[info->emu.vpar[3]];
        else
                audio_len = 0;
        skb = dev_alloc_skb(skb_res + buflen + audio_len);
#else
        skb = dev_alloc_skb(skb_res + buflen);
#endif
        if (!skb) {
                printk(KERN_WARNING
                       "isdn_tty: Out of memory in ttyI%d senddown\n",
                       info->line);
                return;
        }
        skb_reserve(skb, skb_res);
        memcpy(skb_put(skb, buflen), info->port.xmit_buf, buflen);
        info->xmit_count = 0;
#ifdef CONFIG_ISDN_AUDIO
        if (info->vonline & 2) {
                /* For now, ifmt is fixed to 1 (alaw), since this
                 * is used with ISDN everywhere in the world, except
                 * US, Canada and Japan.
                 * Later, when US-ISDN protocols are implemented,
                 * this setting will depend on the D-channel protocol.
                 */
                int ifmt = 1;

                /* voice conversion/decompression */
                switch (info->emu.vpar[3]) {
                case 2:
                case 3:
                case 4:
                        /* adpcm, compatible to ZyXel 1496 modem
                         * with ROM revision 6.01
                         */
                        audio_len = isdn_audio_adpcm2xlaw(info->adpcms,
                                                          ifmt,
                                                          skb->data,
                                                          skb_put(skb, audio_len),
                                                          buflen);
                        skb_pull(skb, buflen);
                        skb_trim(skb, audio_len);
                        break;
                case 5:
                        /* a-law */
                        if (!ifmt)
                                isdn_audio_alaw2ulaw(skb->data,
                                                     buflen);
                        break;
                case 6:
                        /* u-law */
                        if (ifmt)
                                isdn_audio_ulaw2alaw(skb->data,
                                                     buflen);
                        break;
                }
        }
#endif                          /* CONFIG_ISDN_AUDIO */
        if (info->emu.mdmreg[REG_T70] & BIT_T70) {
                /* Add T.70 simplified header */
                if (info->emu.mdmreg[REG_T70] & BIT_T70_EXT)
                        memcpy(skb_push(skb, 2), "\1\0", 2);
                else
                        memcpy(skb_push(skb, 4), "\1\0\1\0", 4);
        }
        skb_queue_tail(&info->xmit_queue, skb);
}

/************************************************************
 *
 * Modem-functions
 *
 * mostly "stolen" from original Linux-serial.c and friends.
 *
 ************************************************************/

/* The next routine is called once from within timer-interrupt
 * triggered within isdn_tty_modem_ncarrier(). It calls
 * isdn_tty_modem_result() to stuff a "NO CARRIER" Message
 * into the tty's buffer.
 */
static void
isdn_tty_modem_do_ncarrier(unsigned long data)
{
        modem_info *info = (modem_info *) data;
        isdn_tty_modem_result(RESULT_NO_CARRIER, info);
}

/* Next routine is called, whenever the DTR-signal is raised.
 * It checks the ncarrier-flag, and triggers the above routine
 * when necessary. The ncarrier-flag is set, whenever DTR goes
 * low.
 */
static void
isdn_tty_modem_ncarrier(modem_info *info)
{
        if (info->ncarrier) {
                info->nc_timer.expires = jiffies + HZ;
                add_timer(&info->nc_timer);
        }
}

/*
 * return the usage calculated by si and layer 2 protocol
 */
static int
isdn_calc_usage(int si, int l2)
{
        int usg = ISDN_USAGE_MODEM;

#ifdef CONFIG_ISDN_AUDIO
        if (si == 1) {
                switch (l2) {
                case ISDN_PROTO_L2_MODEM:
                        usg = ISDN_USAGE_MODEM;
                        break;
#ifdef CONFIG_ISDN_TTY_FAX
                case ISDN_PROTO_L2_FAX:
                        usg = ISDN_USAGE_FAX;
                        break;
#endif
                case ISDN_PROTO_L2_TRANS:
                default:
                        usg = ISDN_USAGE_VOICE;
                        break;
                }
        }
#endif
        return (usg);
}

/* isdn_tty_dial() performs dialing of a tty an the necessary
 * setup of the lower levels before that.
 */
static void
isdn_tty_dial(char *n, modem_info *info, atemu *m)
{
        int usg = ISDN_USAGE_MODEM;
        int si = 7;
        int l2 = m->mdmreg[REG_L2PROT];
        u_long flags;
        isdn_ctrl cmd;
        int i;
        int j;

        for (j = 7; j >= 0; j--)
                if (m->mdmreg[REG_SI1] & (1 << j)) {
                        si = bit2si[j];
                        break;
                }
        usg = isdn_calc_usage(si, l2);
#ifdef CONFIG_ISDN_AUDIO
        if ((si == 1) &&
            (l2 != ISDN_PROTO_L2_MODEM)
#ifdef CONFIG_ISDN_TTY_FAX
            && (l2 != ISDN_PROTO_L2_FAX)
#endif
                ) {
                l2 = ISDN_PROTO_L2_TRANS;
                usg = ISDN_USAGE_VOICE;
        }
#endif
        m->mdmreg[REG_SI1I] = si2bit[si];
        spin_lock_irqsave(&dev->lock, flags);
        i = isdn_get_free_channel(usg, l2, m->mdmreg[REG_L3PROT], -1, -1, m->msn);
        if (i < 0) {
                spin_unlock_irqrestore(&dev->lock, flags);
                isdn_tty_modem_result(RESULT_NO_DIALTONE, info);
        } else {
                info->isdn_driver = dev->drvmap[i];
                info->isdn_channel = dev->chanmap[i];
                info->drv_index = i;
                dev->m_idx[i] = info->line;
                dev->usage[i] |= ISDN_USAGE_OUTGOING;
                info->last_dir = 1;
                strcpy(info->last_num, n);
                isdn_info_update();
                spin_unlock_irqrestore(&dev->lock, flags);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                cmd.command = ISDN_CMD_CLREAZ;
                isdn_command(&cmd);
                strcpy(cmd.parm.num, isdn_map_eaz2msn(m->msn, info->isdn_driver));
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETEAZ;
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL2;
                info->last_l2 = l2;
                cmd.arg = info->isdn_channel + (l2 << 8);
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL3;
                cmd.arg = info->isdn_channel + (m->mdmreg[REG_L3PROT] << 8);
#ifdef CONFIG_ISDN_TTY_FAX
                if (l2 == ISDN_PROTO_L2_FAX) {
                        cmd.parm.fax = info->fax;
                        info->fax->direction = ISDN_TTY_FAX_CONN_OUT;
                }
#endif
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                sprintf(cmd.parm.setup.phone, "%s", n);
                sprintf(cmd.parm.setup.eazmsn, "%s",
                        isdn_map_eaz2msn(m->msn, info->isdn_driver));
                cmd.parm.setup.si1 = si;
                cmd.parm.setup.si2 = m->mdmreg[REG_SI2];
                cmd.command = ISDN_CMD_DIAL;
                info->dialing = 1;
                info->emu.carrierwait = 0;
                strcpy(dev->num[i], n);
                isdn_info_update();
                isdn_command(&cmd);
                isdn_timer_ctrl(ISDN_TIMER_CARRIER, 1);
        }
}

/* isdn_tty_hangup() disassociates a tty from the real
 * ISDN-line (hangup). The usage-status is cleared
 * and some cleanup is done also.
 */
void
isdn_tty_modem_hup(modem_info *info, int local)
{
        isdn_ctrl cmd;
        int di, ch;

        if (!info)
                return;

        di = info->isdn_driver;
        ch = info->isdn_channel;
        if (di < 0 || ch < 0)
                return;

        info->isdn_driver = -1;
        info->isdn_channel = -1;

#ifdef ISDN_DEBUG_MODEM_HUP
        printk(KERN_DEBUG "Mhup ttyI%d\n", info->line);
#endif
        info->rcvsched = 0;
        isdn_tty_flush_buffer(info->port.tty);
        if (info->online) {
                info->last_lhup = local;
                info->online = 0;
                isdn_tty_modem_result(RESULT_NO_CARRIER, info);
        }
#ifdef CONFIG_ISDN_AUDIO
        info->vonline = 0;
#ifdef CONFIG_ISDN_TTY_FAX
        info->faxonline = 0;
        info->fax->phase = ISDN_FAX_PHASE_IDLE;
#endif
        info->emu.vpar[4] = 0;
        info->emu.vpar[5] = 8;
        kfree(info->dtmf_state);
        info->dtmf_state = NULL;
        kfree(info->silence_state);
        info->silence_state = NULL;
        kfree(info->adpcms);
        info->adpcms = NULL;
        kfree(info->adpcmr);
        info->adpcmr = NULL;
#endif
        if ((info->msr & UART_MSR_RI) &&
            (info->emu.mdmreg[REG_RUNG] & BIT_RUNG))
                isdn_tty_modem_result(RESULT_RUNG, info);
        info->msr &= ~(UART_MSR_DCD | UART_MSR_RI);
        info->lsr |= UART_LSR_TEMT;

        if (local) {
                cmd.driver = di;
                cmd.command = ISDN_CMD_HANGUP;
                cmd.arg = ch;
                isdn_command(&cmd);
        }

        isdn_all_eaz(di, ch);
        info->emu.mdmreg[REG_RINGCNT] = 0;
        isdn_free_channel(di, ch, 0);

        if (info->drv_index >= 0) {
                dev->m_idx[info->drv_index] = -1;
                info->drv_index = -1;
        }
}

/*
 * Begin of a CAPI like interface, currently used only for
 * supplementary service (CAPI 2.0 part III)
 */
#include <linux/isdn/capicmd.h>
#include <linux/module.h>

int
isdn_tty_capi_facility(capi_msg *cm) {
        return (-1); /* dummy */
}

/* isdn_tty_suspend() tries to suspend the current tty connection
 */
static void
isdn_tty_suspend(char *id, modem_info *info, atemu *m)
{
        isdn_ctrl cmd;

        int l;

        if (!info)
                return;

#ifdef ISDN_DEBUG_MODEM_SERVICES
        printk(KERN_DEBUG "Msusp ttyI%d\n", info->line);
#endif
        l = strlen(id);
        if ((info->isdn_driver >= 0)) {
                cmd.parm.cmsg.Length = l + 18;
                cmd.parm.cmsg.Command = CAPI_FACILITY;
                cmd.parm.cmsg.Subcommand = CAPI_REQ;
                cmd.parm.cmsg.adr.Controller = info->isdn_driver + 1;
                cmd.parm.cmsg.para[0] = 3; /* 16 bit 0x0003 suplementary service */
                cmd.parm.cmsg.para[1] = 0;
                cmd.parm.cmsg.para[2] = l + 3;
                cmd.parm.cmsg.para[3] = 4; /* 16 bit 0x0004 Suspend */
                cmd.parm.cmsg.para[4] = 0;
                cmd.parm.cmsg.para[5] = l;
                strncpy(&cmd.parm.cmsg.para[6], id, l);
                cmd.command = CAPI_PUT_MESSAGE;
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                isdn_command(&cmd);
        }
}

/* isdn_tty_resume() tries to resume a suspended call
 * setup of the lower levels before that. unfortunately here is no
 * checking for compatibility of used protocols implemented by Q931
 * It does the same things like isdn_tty_dial, the last command
 * is different, may be we can merge it.
 */

static void
isdn_tty_resume(char *id, modem_info *info, atemu *m)
{
        int usg = ISDN_USAGE_MODEM;
        int si = 7;
        int l2 = m->mdmreg[REG_L2PROT];
        isdn_ctrl cmd;
        ulong flags;
        int i;
        int j;
        int l;

        l = strlen(id);
        for (j = 7; j >= 0; j--)
                if (m->mdmreg[REG_SI1] & (1 << j)) {
                        si = bit2si[j];
                        break;
                }
        usg = isdn_calc_usage(si, l2);
#ifdef CONFIG_ISDN_AUDIO
        if ((si == 1) &&
            (l2 != ISDN_PROTO_L2_MODEM)
#ifdef CONFIG_ISDN_TTY_FAX
            && (l2 != ISDN_PROTO_L2_FAX)
#endif
                ) {
                l2 = ISDN_PROTO_L2_TRANS;
                usg = ISDN_USAGE_VOICE;
        }
#endif
        m->mdmreg[REG_SI1I] = si2bit[si];
        spin_lock_irqsave(&dev->lock, flags);
        i = isdn_get_free_channel(usg, l2, m->mdmreg[REG_L3PROT], -1, -1, m->msn);
        if (i < 0) {
                spin_unlock_irqrestore(&dev->lock, flags);
                isdn_tty_modem_result(RESULT_NO_DIALTONE, info);
        } else {
                info->isdn_driver = dev->drvmap[i];
                info->isdn_channel = dev->chanmap[i];
                info->drv_index = i;
                dev->m_idx[i] = info->line;
                dev->usage[i] |= ISDN_USAGE_OUTGOING;
                info->last_dir = 1;
//              strcpy(info->last_num, n);
                isdn_info_update();
                spin_unlock_irqrestore(&dev->lock, flags);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                cmd.command = ISDN_CMD_CLREAZ;
                isdn_command(&cmd);
                strcpy(cmd.parm.num, isdn_map_eaz2msn(m->msn, info->isdn_driver));
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETEAZ;
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL2;
                info->last_l2 = l2;
                cmd.arg = info->isdn_channel + (l2 << 8);
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL3;
                cmd.arg = info->isdn_channel + (m->mdmreg[REG_L3PROT] << 8);
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                cmd.parm.cmsg.Length = l + 18;
                cmd.parm.cmsg.Command = CAPI_FACILITY;
                cmd.parm.cmsg.Subcommand = CAPI_REQ;
                cmd.parm.cmsg.adr.Controller = info->isdn_driver + 1;
                cmd.parm.cmsg.para[0] = 3; /* 16 bit 0x0003 suplementary service */
                cmd.parm.cmsg.para[1] = 0;
                cmd.parm.cmsg.para[2] = l + 3;
                cmd.parm.cmsg.para[3] = 5; /* 16 bit 0x0005 Resume */
                cmd.parm.cmsg.para[4] = 0;
                cmd.parm.cmsg.para[5] = l;
                strncpy(&cmd.parm.cmsg.para[6], id, l);
                cmd.command = CAPI_PUT_MESSAGE;
                info->dialing = 1;
//              strcpy(dev->num[i], n);
                isdn_info_update();
                isdn_command(&cmd);
                isdn_timer_ctrl(ISDN_TIMER_CARRIER, 1);
        }
}

/* isdn_tty_send_msg() sends a message to a HL driver
 * This is used for hybrid modem cards to send AT commands to it
 */

static void
isdn_tty_send_msg(modem_info *info, atemu *m, char *msg)
{
        int usg = ISDN_USAGE_MODEM;
        int si = 7;
        int l2 = m->mdmreg[REG_L2PROT];
        isdn_ctrl cmd;
        ulong flags;
        int i;
        int j;
        int l;

        l = min(strlen(msg), sizeof(cmd.parm) - sizeof(cmd.parm.cmsg)
                + sizeof(cmd.parm.cmsg.para) - 2);

        if (!l) {
                isdn_tty_modem_result(RESULT_ERROR, info);
                return;
        }
        for (j = 7; j >= 0; j--)
                if (m->mdmreg[REG_SI1] & (1 << j)) {
                        si = bit2si[j];
                        break;
                }
        usg = isdn_calc_usage(si, l2);
#ifdef CONFIG_ISDN_AUDIO
        if ((si == 1) &&
            (l2 != ISDN_PROTO_L2_MODEM)
#ifdef CONFIG_ISDN_TTY_FAX
            && (l2 != ISDN_PROTO_L2_FAX)
#endif
                ) {
                l2 = ISDN_PROTO_L2_TRANS;
                usg = ISDN_USAGE_VOICE;
        }
#endif
        m->mdmreg[REG_SI1I] = si2bit[si];
        spin_lock_irqsave(&dev->lock, flags);
        i = isdn_get_free_channel(usg, l2, m->mdmreg[REG_L3PROT], -1, -1, m->msn);
        if (i < 0) {
                spin_unlock_irqrestore(&dev->lock, flags);
                isdn_tty_modem_result(RESULT_NO_DIALTONE, info);
        } else {
                info->isdn_driver = dev->drvmap[i];
                info->isdn_channel = dev->chanmap[i];
                info->drv_index = i;
                dev->m_idx[i] = info->line;
                dev->usage[i] |= ISDN_USAGE_OUTGOING;
                info->last_dir = 1;
                isdn_info_update();
                spin_unlock_irqrestore(&dev->lock, flags);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                cmd.command = ISDN_CMD_CLREAZ;
                isdn_command(&cmd);
                strcpy(cmd.parm.num, isdn_map_eaz2msn(m->msn, info->isdn_driver));
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETEAZ;
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL2;
                info->last_l2 = l2;
                cmd.arg = info->isdn_channel + (l2 << 8);
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL3;
                cmd.arg = info->isdn_channel + (m->mdmreg[REG_L3PROT] << 8);
                isdn_command(&cmd);
                cmd.driver = info->isdn_driver;
                cmd.arg = info->isdn_channel;
                cmd.parm.cmsg.Length = l + 14;
                cmd.parm.cmsg.Command = CAPI_MANUFACTURER;
                cmd.parm.cmsg.Subcommand = CAPI_REQ;
                cmd.parm.cmsg.adr.Controller = info->isdn_driver + 1;
                cmd.parm.cmsg.para[0] = l + 1;
                strncpy(&cmd.parm.cmsg.para[1], msg, l);
                cmd.parm.cmsg.para[l + 1] = 0xd;
                cmd.command = CAPI_PUT_MESSAGE;
/*              info->dialing = 1;
                strcpy(dev->num[i], n);
                isdn_info_update();
*/
                isdn_command(&cmd);
        }
}

static inline int
isdn_tty_paranoia_check(modem_info *info, char *name, const char *routine)
{
#ifdef MODEM_PARANOIA_CHECK
        if (!info) {
                printk(KERN_WARNING "isdn_tty: null info_struct for %s in %s\n",
                       name, routine);
                return 1;
        }
        if (info->magic != ISDN_ASYNC_MAGIC) {
                printk(KERN_WARNING "isdn_tty: bad magic for modem struct %s in %s\n",
                       name, routine);
                return 1;
        }
#endif
        return 0;
}

/*
 * This routine is called to set the UART divisor registers to match
 * the specified baud rate for a serial port.
 */

static void
isdn_tty_change_speed(modem_info *info)
{
        struct tty_port *port = &info->port;
        uint cflag,
                cval,
                quot;
        int i;

        if (!port->tty)
                return;
        cflag = port->tty->termios.c_cflag;

        quot = i = cflag & CBAUD;
        if (i & CBAUDEX) {
                i &= ~CBAUDEX;
                if (i < 1 || i > 2)
                        port->tty->termios.c_cflag &= ~CBAUDEX;
                else
                        i += 15;
        }
        if (quot) {
                info->mcr |= UART_MCR_DTR;
                isdn_tty_modem_ncarrier(info);
        } else {
                info->mcr &= ~UART_MCR_DTR;
                if (info->emu.mdmreg[REG_DTRHUP] & BIT_DTRHUP) {
#ifdef ISDN_DEBUG_MODEM_HUP
                        printk(KERN_DEBUG "Mhup in changespeed\n");
#endif
                        if (info->online)
                                info->ncarrier = 1;
                        isdn_tty_modem_reset_regs(info, 0);
                        isdn_tty_modem_hup(info, 1);
                }
                return;
        }
        /* byte size and parity */
        cval = cflag & (CSIZE | CSTOPB);
        cval >>= 4;
        if (cflag & PARENB)
                cval |= UART_LCR_PARITY;
        if (!(cflag & PARODD))
                cval |= UART_LCR_EPAR;

        if (cflag & CLOCAL)
                port->flags &= ~ASYNC_CHECK_CD;
        else {
                port->flags |= ASYNC_CHECK_CD;
        }
}

static int
isdn_tty_startup(modem_info *info)
{
        if (info->port.flags & ASYNC_INITIALIZED)
                return 0;
        isdn_lock_drivers();
#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "starting up ttyi%d ...\n", info->line);
#endif
        /*
         * Now, initialize the UART
         */
        info->mcr = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
        if (info->port.tty)
                clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
        /*
         * and set the speed of the serial port
         */
        isdn_tty_change_speed(info);

        info->port.flags |= ASYNC_INITIALIZED;
        info->msr |= (UART_MSR_DSR | UART_MSR_CTS);
        info->send_outstanding = 0;
        return 0;
}

/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static void
isdn_tty_shutdown(modem_info *info)
{
        if (!(info->port.flags & ASYNC_INITIALIZED))
                return;
#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "Shutting down isdnmodem port %d ....\n", info->line);
#endif
        isdn_unlock_drivers();
        info->msr &= ~UART_MSR_RI;
        if (!info->port.tty || (info->port.tty->termios.c_cflag & HUPCL)) {
                info->mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
                if (info->emu.mdmreg[REG_DTRHUP] & BIT_DTRHUP) {
                        isdn_tty_modem_reset_regs(info, 0);
#ifdef ISDN_DEBUG_MODEM_HUP
                        printk(KERN_DEBUG "Mhup in isdn_tty_shutdown\n");
#endif
                        isdn_tty_modem_hup(info, 1);
                }
        }
        if (info->port.tty)
                set_bit(TTY_IO_ERROR, &info->port.tty->flags);

        info->port.flags &= ~ASYNC_INITIALIZED;
}

/* isdn_tty_write() is the main send-routine. It is called from the upper
 * levels within the kernel to perform sending data. Depending on the
 * online-flag it either directs output to the at-command-interpreter or
 * to the lower level. Additional tasks done here:
 *  - If online, check for escape-sequence (+++)
 *  - If sending audio-data, call isdn_tty_DLEdown() to parse DLE-codes.
 *  - If receiving audio-data, call isdn_tty_end_vrx() to abort if needed.
 *  - If dialing, abort dial.
 */
static int
isdn_tty_write(struct tty_struct *tty, const u_char *buf, int count)
{
        int c;
        int total = 0;
        modem_info *info = (modem_info *) tty->driver_data;
        atemu *m = &info->emu;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_write"))
                return 0;
        /* See isdn_tty_senddown() */
        atomic_inc(&info->xmit_lock);
        while (1) {
                c = count;
                if (c > info->xmit_size - info->xmit_count)
                        c = info->xmit_size - info->xmit_count;
                if (info->isdn_driver >= 0 && c > dev->drv[info->isdn_driver]->maxbufsize)
                        c = dev->drv[info->isdn_driver]->maxbufsize;
                if (c <= 0)
                        break;
                if ((info->online > 1)
#ifdef CONFIG_ISDN_AUDIO
                    || (info->vonline & 3)
#endif
                        ) {
#ifdef CONFIG_ISDN_AUDIO
                        if (!info->vonline)
#endif
                                isdn_tty_check_esc(buf, m->mdmreg[REG_ESC], c,
                                                   &(m->pluscount),
                                                   &(m->lastplus));
                        memcpy(&info->port.xmit_buf[info->xmit_count], buf, c);
#ifdef CONFIG_ISDN_AUDIO
                        if (info->vonline) {
                                int cc = isdn_tty_handleDLEdown(info, m, c);
                                if (info->vonline & 2) {
                                        if (!cc) {
                                                /* If DLE decoding results in zero-transmit, but
                                                 * c originally was non-zero, do a wakeup.
                                                 */
                                                tty_wakeup(tty);
                                                info->msr |= UART_MSR_CTS;
                                                info->lsr |= UART_LSR_TEMT;
                                        }
                                        info->xmit_count += cc;
                                }
                                if ((info->vonline & 3) == 1) {
                                        /* Do NOT handle Ctrl-Q or Ctrl-S
                                         * when in full-duplex audio mode.
                                         */
                                        if (isdn_tty_end_vrx(buf, c)) {
                                                info->vonline &= ~1;
#ifdef ISDN_DEBUG_MODEM_VOICE
                                                printk(KERN_DEBUG
                                                       "got !^Q/^S, send DLE-ETX,VCON on ttyI%d\n",
                                                       info->line);
#endif
                                                isdn_tty_at_cout("\020\003\r\nVCON\r\n", info);
                                        }
                                }
                        } else
                                if (TTY_IS_FCLASS1(info)) {
                                        int cc = isdn_tty_handleDLEdown(info, m, c);

                                        if (info->vonline & 4) { /* ETX seen */
                                                isdn_ctrl c;

                                                c.command = ISDN_CMD_FAXCMD;
                                                c.driver = info->isdn_driver;
                                                c.arg = info->isdn_channel;
                                                c.parm.aux.cmd = ISDN_FAX_CLASS1_CTRL;
                                                c.parm.aux.subcmd = ETX;
                                                isdn_command(&c);
                                        }
                                        info->vonline = 0;
#ifdef ISDN_DEBUG_MODEM_VOICE
                                        printk(KERN_DEBUG "fax dle cc/c %d/%d\n", cc, c);
#endif
                                        info->xmit_count += cc;
                                } else
#endif
                                        info->xmit_count += c;
                } else {
                        info->msr |= UART_MSR_CTS;
                        info->lsr |= UART_LSR_TEMT;
                        if (info->dialing) {
                                info->dialing = 0;
#ifdef ISDN_DEBUG_MODEM_HUP
                                printk(KERN_DEBUG "Mhup in isdn_tty_write\n");
#endif
                                isdn_tty_modem_result(RESULT_NO_CARRIER, info);
                                isdn_tty_modem_hup(info, 1);
                        } else
                                c = isdn_tty_edit_at(buf, c, info);
                }
                buf += c;
                count -= c;
                total += c;
        }
        atomic_dec(&info->xmit_lock);
        if ((info->xmit_count) || !skb_queue_empty(&info->xmit_queue)) {
                if (m->mdmreg[REG_DXMT] & BIT_DXMT) {
                        isdn_tty_senddown(info);
                        isdn_tty_tint(info);
                }
                isdn_timer_ctrl(ISDN_TIMER_MODEMXMIT, 1);
        }
        return total;
}

static int
isdn_tty_write_room(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;
        int ret;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_write_room"))
                return 0;
        if (!info->online)
                return info->xmit_size;
        ret = info->xmit_size - info->xmit_count;
        return (ret < 0) ? 0 : ret;
}

static int
isdn_tty_chars_in_buffer(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_chars_in_buffer"))
                return 0;
        if (!info->online)
                return 0;
        return (info->xmit_count);
}

static void
isdn_tty_flush_buffer(struct tty_struct *tty)
{
        modem_info *info;

        if (!tty) {
                return;
        }
        info = (modem_info *) tty->driver_data;
        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_flush_buffer")) {
                return;
        }
        isdn_tty_cleanup_xmit(info);
        info->xmit_count = 0;
        tty_wakeup(tty);
}

static void
isdn_tty_flush_chars(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_flush_chars"))
                return;
        if ((info->xmit_count) || !skb_queue_empty(&info->xmit_queue))
                isdn_timer_ctrl(ISDN_TIMER_MODEMXMIT, 1);
}

/*
 * ------------------------------------------------------------
 * isdn_tty_throttle()
 *
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void
isdn_tty_throttle(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_throttle"))
                return;
        if (I_IXOFF(tty))
                info->x_char = STOP_CHAR(tty);
        info->mcr &= ~UART_MCR_RTS;
}

static void
isdn_tty_unthrottle(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_unthrottle"))
                return;
        if (I_IXOFF(tty)) {
                if (info->x_char)
                        info->x_char = 0;
                else
                        info->x_char = START_CHAR(tty);
        }
        info->mcr |= UART_MCR_RTS;
}

/*
 * ------------------------------------------------------------
 * isdn_tty_ioctl() and friends
 * ------------------------------------------------------------
 */

/*
 * isdn_tty_get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 *          is emptied.  On bus types like RS485, the transmitter must
 *          release the bus after transmitting. This must be done when
 *          the transmit shift register is empty, not be done when the
 *          transmit holding register is empty.  This functionality
 *          allows RS485 driver to be written in user space.
 */
static int
isdn_tty_get_lsr_info(modem_info *info, uint __user *value)
{
        u_char status;
        uint result;

        status = info->lsr;
        result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
        return put_user(result, value);
}


static int
isdn_tty_tiocmget(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;
        u_char control, status;

        if (isdn_tty_paranoia_check(info, tty->name, __func__))
                return -ENODEV;
        if (tty->flags & (1 << TTY_IO_ERROR))
                return -EIO;

        mutex_lock(&modem_info_mutex);
#ifdef ISDN_DEBUG_MODEM_IOCTL
        printk(KERN_DEBUG "ttyI%d ioctl TIOCMGET\n", info->line);
#endif

        control = info->mcr;
        status = info->msr;
        mutex_unlock(&modem_info_mutex);
        return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
                | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
                | ((status & UART_MSR_DCD) ? TIOCM_CAR : 0)
                | ((status & UART_MSR_RI) ? TIOCM_RNG : 0)
                | ((status & UART_MSR_DSR) ? TIOCM_DSR : 0)
                | ((status & UART_MSR_CTS) ? TIOCM_CTS : 0);
}

static int
isdn_tty_tiocmset(struct tty_struct *tty,
                  unsigned int set, unsigned int clear)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (isdn_tty_paranoia_check(info, tty->name, __func__))
                return -ENODEV;
        if (tty->flags & (1 << TTY_IO_ERROR))
                return -EIO;

#ifdef ISDN_DEBUG_MODEM_IOCTL
        printk(KERN_DEBUG "ttyI%d ioctl TIOCMxxx: %x %x\n", info->line, set, clear);
#endif

        mutex_lock(&modem_info_mutex);
        if (set & TIOCM_RTS)
                info->mcr |= UART_MCR_RTS;
        if (set & TIOCM_DTR) {
                info->mcr |= UART_MCR_DTR;
                isdn_tty_modem_ncarrier(info);
        }

        if (clear & TIOCM_RTS)
                info->mcr &= ~UART_MCR_RTS;
        if (clear & TIOCM_DTR) {
                info->mcr &= ~UART_MCR_DTR;
                if (info->emu.mdmreg[REG_DTRHUP] & BIT_DTRHUP) {
                        isdn_tty_modem_reset_regs(info, 0);
#ifdef ISDN_DEBUG_MODEM_HUP
                        printk(KERN_DEBUG "Mhup in TIOCMSET\n");
#endif
                        if (info->online)
                                info->ncarrier = 1;
                        isdn_tty_modem_hup(info, 1);
                }
        }
        mutex_unlock(&modem_info_mutex);
        return 0;
}

static int
isdn_tty_ioctl(struct tty_struct *tty, uint cmd, ulong arg)
{
        modem_info *info = (modem_info *) tty->driver_data;
        int retval;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_ioctl"))
                return -ENODEV;
        if (tty->flags & (1 << TTY_IO_ERROR))
                return -EIO;
        switch (cmd) {
        case TCSBRK:   /* SVID version: non-zero arg --> no break */
#ifdef ISDN_DEBUG_MODEM_IOCTL
                printk(KERN_DEBUG "ttyI%d ioctl TCSBRK\n", info->line);
#endif
                retval = tty_check_change(tty);
                if (retval)
                        return retval;
                tty_wait_until_sent(tty, 0);
                return 0;
        case TCSBRKP:  /* support for POSIX tcsendbreak() */
#ifdef ISDN_DEBUG_MODEM_IOCTL
                printk(KERN_DEBUG "ttyI%d ioctl TCSBRKP\n", info->line);
#endif
                retval = tty_check_change(tty);
                if (retval)
                        return retval;
                tty_wait_until_sent(tty, 0);
                return 0;
        case TIOCSERGETLSR:     /* Get line status register */
#ifdef ISDN_DEBUG_MODEM_IOCTL
                printk(KERN_DEBUG "ttyI%d ioctl TIOCSERGETLSR\n", info->line);
#endif
                return isdn_tty_get_lsr_info(info, (uint __user *) arg);
        default:
#ifdef ISDN_DEBUG_MODEM_IOCTL
                printk(KERN_DEBUG "UNKNOWN ioctl 0x%08x on ttyi%d\n", cmd, info->line);
#endif
                return -ENOIOCTLCMD;
        }
        return 0;
}

static void
isdn_tty_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
{
        modem_info *info = (modem_info *) tty->driver_data;

        if (!old_termios)
                isdn_tty_change_speed(info);
        else {
                if (tty->termios.c_cflag == old_termios->c_cflag &&
                    tty->termios.c_ispeed == old_termios->c_ispeed &&
                    tty->termios.c_ospeed == old_termios->c_ospeed)
                        return;
                isdn_tty_change_speed(info);
        }
}

/*
 * ------------------------------------------------------------
 * isdn_tty_open() and friends
 * ------------------------------------------------------------
 */

static int isdn_tty_install(struct tty_driver *driver, struct tty_struct *tty)
{
        modem_info *info = &dev->mdm.info[tty->index];

        if (isdn_tty_paranoia_check(info, tty->name, __func__))
                return -ENODEV;

        tty->driver_data = info;

        return tty_port_install(&info->port, driver, tty);
}

/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int
isdn_tty_open(struct tty_struct *tty, struct file *filp)
{
        modem_info *info = tty->driver_data;
        struct tty_port *port = &info->port;
        int retval;

#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "isdn_tty_open %s, count = %d\n", tty->name,
               port->count);
#endif
        port->count++;
        port->tty = tty;
        /*
         * Start up serial port
         */
        retval = isdn_tty_startup(info);
        if (retval) {
#ifdef ISDN_DEBUG_MODEM_OPEN
                printk(KERN_DEBUG "isdn_tty_open return after startup\n");
#endif
                return retval;
        }
        retval = tty_port_block_til_ready(port, tty, filp);
        if (retval) {
#ifdef ISDN_DEBUG_MODEM_OPEN
                printk(KERN_DEBUG "isdn_tty_open return after isdn_tty_block_til_ready \n");
#endif
                return retval;
        }
#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "isdn_tty_open ttyi%d successful...\n", info->line);
#endif
        dev->modempoll++;
#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "isdn_tty_open normal exit\n");
#endif
        return 0;
}

static void
isdn_tty_close(struct tty_struct *tty, struct file *filp)
{
        modem_info *info = (modem_info *) tty->driver_data;
        struct tty_port *port = &info->port;
        ulong timeout;

        if (!info || isdn_tty_paranoia_check(info, tty->name, "isdn_tty_close"))
                return;
        if (tty_hung_up_p(filp)) {
#ifdef ISDN_DEBUG_MODEM_OPEN
                printk(KERN_DEBUG "isdn_tty_close return after tty_hung_up_p\n");
#endif
                return;
        }
        if ((tty->count == 1) && (port->count != 1)) {
                /*
                 * Uh, oh.  tty->count is 1, which means that the tty
                 * structure will be freed.  Info->count should always
                 * be one in these conditions.  If it's greater than
                 * one, we've got real problems, since it means the
                 * serial port won't be shutdown.
                 */
                printk(KERN_ERR "isdn_tty_close: bad port count; tty->count is 1, "
                       "info->count is %d\n", port->count);
                port->count = 1;
        }
        if (--port->count < 0) {
                printk(KERN_ERR "isdn_tty_close: bad port count for ttyi%d: %d\n",
                       info->line, port->count);
                port->count = 0;
        }
        if (port->count) {
#ifdef ISDN_DEBUG_MODEM_OPEN
                printk(KERN_DEBUG "isdn_tty_close after info->count != 0\n");
#endif
                return;
        }
        port->flags |= ASYNC_CLOSING;

        tty->closing = 1;
        /*
         * At this point we stop accepting input.  To do this, we
         * disable the receive line status interrupts, and tell the
         * interrupt driver to stop checking the data ready bit in the
         * line status register.
         */
        if (port->flags & ASYNC_INITIALIZED) {
                tty_wait_until_sent_from_close(tty, 3000);      /* 30 seconds timeout */
                /*
                 * Before we drop DTR, make sure the UART transmitter
                 * has completely drained; this is especially
                 * important if there is a transmit FIFO!
                 */
                timeout = jiffies + HZ;
                while (!(info->lsr & UART_LSR_TEMT)) {
                        schedule_timeout_interruptible(20);
                        if (time_after(jiffies, timeout))
                                break;
                }
        }
        dev->modempoll--;
        isdn_tty_shutdown(info);
        isdn_tty_flush_buffer(tty);
        tty_ldisc_flush(tty);
        port->tty = NULL;
        info->ncarrier = 0;

        tty_port_close_end(port, tty);
#ifdef ISDN_DEBUG_MODEM_OPEN
        printk(KERN_DEBUG "isdn_tty_close normal exit\n");
#endif
}

/*
 * isdn_tty_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void
isdn_tty_hangup(struct tty_struct *tty)
{
        modem_info *info = (modem_info *) tty->driver_data;
        struct tty_port *port = &info->port;

        if (isdn_tty_paranoia_check(info, tty->name, "isdn_tty_hangup"))
                return;
        isdn_tty_shutdown(info);
        port->count = 0;
        port->flags &= ~ASYNC_NORMAL_ACTIVE;
        port->tty = NULL;
        wake_up_interruptible(&port->open_wait);
}

/* This routine initializes all emulator-data.
 */
static void
isdn_tty_reset_profile(atemu *m)
{
        m->profile[0] = 0;
        m->profile[1] = 0;
        m->profile[2] = 43;
        m->profile[3] = 13;
        m->profile[4] = 10;
        m->profile[5] = 8;
        m->profile[6] = 3;
        m->profile[7] = 60;
        m->profile[8] = 2;
        m->profile[9] = 6;
        m->profile[10] = 7;
        m->profile[11] = 70;
        m->profile[12] = 0x45;
        m->profile[13] = 4;
        m->profile[14] = ISDN_PROTO_L2_X75I;
        m->profile[15] = ISDN_PROTO_L3_TRANS;
        m->profile[16] = ISDN_SERIAL_XMIT_SIZE / 16;
        m->profile[17] = ISDN_MODEM_WINSIZE;
        m->profile[18] = 4;
        m->profile[19] = 0;
        m->profile[20] = 0;
        m->profile[23] = 0;
        m->pmsn[0] = '\0';
        m->plmsn[0] = '\0';
}

#ifdef CONFIG_ISDN_AUDIO
static void
isdn_tty_modem_reset_vpar(atemu *m)
{
        m->vpar[0] = 2;         /* Voice-device            (2 = phone line) */
        m->vpar[1] = 0;         /* Silence detection level (0 = none      ) */
        m->vpar[2] = 70;        /* Silence interval        (7 sec.        ) */
        m->vpar[3] = 2;         /* Compression type        (1 = ADPCM-2   ) */
        m->vpar[4] = 0;         /* DTMF detection level    (0 = softcode  ) */
        m->vpar[5] = 8;         /* DTMF interval           (8 * 5 ms.     ) */
}
#endif

#ifdef CONFIG_ISDN_TTY_FAX
static void
isdn_tty_modem_reset_faxpar(modem_info *info)
{
        T30_s *f = info->fax;

        f->code = 0;
        f->phase = ISDN_FAX_PHASE_IDLE;
        f->direction = 0;
        f->resolution = 1;      /* fine */
        f->rate = 5;            /* 14400 bit/s */
        f->width = 0;
        f->length = 0;
        f->compression = 0;
        f->ecm = 0;
        f->binary = 0;
        f->scantime = 0;
        memset(&f->id[0], 32, FAXIDLEN - 1);
        f->id[FAXIDLEN - 1] = 0;
        f->badlin = 0;
        f->badmul = 0;
        f->bor = 0;
        f->nbc = 0;
        f->cq = 0;
        f->cr = 0;
        f->ctcrty = 0;
        f->minsp = 0;
        f->phcto = 30;
        f->rel = 0;
        memset(&f->pollid[0], 32, FAXIDLEN - 1);
        f->pollid[FAXIDLEN - 1] = 0;
}
#endif

static void
isdn_tty_modem_reset_regs(modem_info *info, int force)
{
        atemu *m = &info->emu;
        if ((m->mdmreg[REG_DTRR] & BIT_DTRR) || force) {
                memcpy(m->mdmreg, m->profile, ISDN_MODEM_NUMREG);
                memcpy(m->msn, m->pmsn, ISDN_MSNLEN);
                memcpy(m->lmsn, m->plmsn, ISDN_LMSNLEN);
                info->xmit_size = m->mdmreg[REG_PSIZE] * 16;
        }
#ifdef CONFIG_ISDN_AUDIO
        isdn_tty_modem_reset_vpar(m);
#endif
#ifdef CONFIG_ISDN_TTY_FAX
        isdn_tty_modem_reset_faxpar(info);
#endif
        m->mdmcmdl = 0;
}

static void
modem_write_profile(atemu *m)
{
        memcpy(m->profile, m->mdmreg, ISDN_MODEM_NUMREG);
        memcpy(m->pmsn, m->msn, ISDN_MSNLEN);
        memcpy(m->plmsn, m->lmsn, ISDN_LMSNLEN);
        if (dev->profd)
                send_sig(SIGIO, dev->profd, 1);
}

static const struct tty_operations modem_ops = {
        .install = isdn_tty_install,
        .open = isdn_tty_open,
        .close = isdn_tty_close,
        .write = isdn_tty_write,
        .flush_chars = isdn_tty_flush_chars,
        .write_room = isdn_tty_write_room,
        .chars_in_buffer = isdn_tty_chars_in_buffer,
        .flush_buffer = isdn_tty_flush_buffer,
        .ioctl = isdn_tty_ioctl,
        .throttle = isdn_tty_throttle,
        .unthrottle = isdn_tty_unthrottle,
        .set_termios = isdn_tty_set_termios,
        .hangup = isdn_tty_hangup,
        .tiocmget = isdn_tty_tiocmget,
        .tiocmset = isdn_tty_tiocmset,
};

static int isdn_tty_carrier_raised(struct tty_port *port)
{
        modem_info *info = container_of(port, modem_info, port);
        return info->msr & UART_MSR_DCD;
}

static const struct tty_port_operations isdn_tty_port_ops = {
        .carrier_raised = isdn_tty_carrier_raised,
};

int
isdn_tty_modem_init(void)
{
        isdn_modem_t    *m;
        int             i, retval;
        modem_info      *info;

        m = &dev->mdm;
        m->tty_modem = alloc_tty_driver(ISDN_MAX_CHANNELS);
        if (!m->tty_modem)
                return -ENOMEM;
        m->tty_modem->name = "ttyI";
        m->tty_modem->major = ISDN_TTY_MAJOR;
        m->tty_modem->minor_start = 0;
        m->tty_modem->type = TTY_DRIVER_TYPE_SERIAL;
        m->tty_modem->subtype = SERIAL_TYPE_NORMAL;
        m->tty_modem->init_termios = tty_std_termios;
        m->tty_modem->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
        m->tty_modem->flags = TTY_DRIVER_REAL_RAW;
        m->tty_modem->driver_name = "isdn_tty";
        tty_set_operations(m->tty_modem, &modem_ops);
        retval = tty_register_driver(m->tty_modem);
        if (retval) {
                printk(KERN_WARNING "isdn_tty: Couldn't register modem-device\n");
                goto err;
        }
        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                info = &m->info[i];
#ifdef CONFIG_ISDN_TTY_FAX
                if (!(info->fax = kmalloc(sizeof(T30_s), GFP_KERNEL))) {
                        printk(KERN_ERR "Could not allocate fax t30-buffer\n");
                        retval = -ENOMEM;
                        goto err_unregister;
                }
#endif
                tty_port_init(&info->port);
                info->port.ops = &isdn_tty_port_ops;
                spin_lock_init(&info->readlock);
                sprintf(info->last_cause, "0000");
                sprintf(info->last_num, "none");
                info->last_dir = 0;
                info->last_lhup = 1;
                info->last_l2 = -1;
                info->last_si = 0;
                isdn_tty_reset_profile(&info->emu);
                isdn_tty_modem_reset_regs(info, 1);
                info->magic = ISDN_ASYNC_MAGIC;
                info->line = i;
                info->x_char = 0;
                info->isdn_driver = -1;
                info->isdn_channel = -1;
                info->drv_index = -1;
                info->xmit_size = ISDN_SERIAL_XMIT_SIZE;
                init_timer(&info->nc_timer);
                info->nc_timer.function = isdn_tty_modem_do_ncarrier;
                info->nc_timer.data = (unsigned long) info;
                skb_queue_head_init(&info->xmit_queue);
#ifdef CONFIG_ISDN_AUDIO
                skb_queue_head_init(&info->dtmf_queue);
#endif
                info->port.xmit_buf = kmalloc(ISDN_SERIAL_XMIT_MAX + 5,
                                GFP_KERNEL);
                if (!info->port.xmit_buf) {
                        printk(KERN_ERR "Could not allocate modem xmit-buffer\n");
                        retval = -ENOMEM;
                        goto err_unregister;
                }
                /* Make room for T.70 header */
                info->port.xmit_buf += 4;
        }
        return 0;
err_unregister:
        for (i--; i >= 0; i--) {
                info = &m->info[i];
#ifdef CONFIG_ISDN_TTY_FAX
                kfree(info->fax);
#endif
                kfree(info->port.xmit_buf - 4);
                info->port.xmit_buf = NULL;
                tty_port_destroy(&info->port);
        }
        tty_unregister_driver(m->tty_modem);
err:
        put_tty_driver(m->tty_modem);
        m->tty_modem = NULL;
        return retval;
}

void
isdn_tty_exit(void)
{
        modem_info *info;
        int i;

        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                info = &dev->mdm.info[i];
                isdn_tty_cleanup_xmit(info);
#ifdef CONFIG_ISDN_TTY_FAX
                kfree(info->fax);
#endif
                kfree(info->port.xmit_buf - 4);
                info->port.xmit_buf = NULL;
                tty_port_destroy(&info->port);
        }
        tty_unregister_driver(dev->mdm.tty_modem);
        put_tty_driver(dev->mdm.tty_modem);
        dev->mdm.tty_modem = NULL;
}


/*
 * isdn_tty_match_icall(char *MSN, atemu *tty_emulator, int dev_idx)
 *      match the MSN against the MSNs (glob patterns) defined for tty_emulator,
 *      and return 0 for match, 1 for no match, 2 if MSN could match if longer.
 */

static int
isdn_tty_match_icall(char *cid, atemu *emu, int di)
{
#ifdef ISDN_DEBUG_MODEM_ICALL
        printk(KERN_DEBUG "m_fi: msn=%s lmsn=%s mmsn=%s mreg[SI1]=%d mreg[SI2]=%d\n",
               emu->msn, emu->lmsn, isdn_map_eaz2msn(emu->msn, di),
               emu->mdmreg[REG_SI1], emu->mdmreg[REG_SI2]);
#endif
        if (strlen(emu->lmsn)) {
                char *p = emu->lmsn;
                char *q;
                int  tmp;
                int  ret = 0;

                while (1) {
                        if ((q = strchr(p, ';')))
                                *q = '\0';
                        if ((tmp = isdn_msncmp(cid, isdn_map_eaz2msn(p, di))) > ret)
                                ret = tmp;
#ifdef ISDN_DEBUG_MODEM_ICALL
                        printk(KERN_DEBUG "m_fi: lmsnX=%s mmsn=%s -> tmp=%d\n",
                               p, isdn_map_eaz2msn(emu->msn, di), tmp);
#endif
                        if (q) {
                                *q = ';';
                                p = q;
                                p++;
                        }
                        if (!tmp)
                                return 0;
                        if (!q)
                                break;
                }
                return ret;
        } else {
                int tmp;
                tmp = isdn_msncmp(cid, isdn_map_eaz2msn(emu->msn, di));
#ifdef ISDN_DEBUG_MODEM_ICALL
                printk(KERN_DEBUG "m_fi: mmsn=%s -> tmp=%d\n",
                       isdn_map_eaz2msn(emu->msn, di), tmp);
#endif
                return tmp;
        }
}

/*
 * An incoming call-request has arrived.
 * Search the tty-devices for an appropriate device and bind
 * it to the ISDN-Channel.
 * Return:
 *
 *  0 = No matching device found.
 *  1 = A matching device found.
 *  3 = No match found, but eventually would match, if
 *      CID is longer.
 */
int
isdn_tty_find_icall(int di, int ch, setup_parm *setup)
{
        char *eaz;
        int i;
        int wret;
        int idx;
        int si1;
        int si2;
        char *nr;
        ulong flags;

        if (!setup->phone[0]) {
                nr = "0";
                printk(KERN_INFO "isdn_tty: Incoming call without OAD, assuming '0'\n");
        } else
                nr = setup->phone;
        si1 = (int) setup->si1;
        si2 = (int) setup->si2;
        if (!setup->eazmsn[0]) {
                printk(KERN_WARNING "isdn_tty: Incoming call without CPN, assuming '0'\n");
                eaz = "0";
        } else
                eaz = setup->eazmsn;
#ifdef ISDN_DEBUG_MODEM_ICALL
        printk(KERN_DEBUG "m_fi: eaz=%s si1=%d si2=%d\n", eaz, si1, si2);
#endif
        wret = 0;
        spin_lock_irqsave(&dev->lock, flags);
        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                modem_info *info = &dev->mdm.info[i];

                if (info->port.count == 0)
                        continue;
                if ((info->emu.mdmreg[REG_SI1] & si2bit[si1]) &&  /* SI1 is matching */
                    (info->emu.mdmreg[REG_SI2] == si2)) {         /* SI2 is matching */
                        idx = isdn_dc2minor(di, ch);
#ifdef ISDN_DEBUG_MODEM_ICALL
                        printk(KERN_DEBUG "m_fi: match1 wret=%d\n", wret);
                        printk(KERN_DEBUG "m_fi: idx=%d flags=%08lx drv=%d ch=%d usg=%d\n", idx,
                               info->port.flags, info->isdn_driver,
                               info->isdn_channel, dev->usage[idx]);
#endif
                        if (
#ifndef FIX_FILE_TRANSFER
                                (info->port.flags & ASYNC_NORMAL_ACTIVE) &&
#endif
                                (info->isdn_driver == -1) &&
                                (info->isdn_channel == -1) &&
                                (USG_NONE(dev->usage[idx]))) {
                                int matchret;

                                if ((matchret = isdn_tty_match_icall(eaz, &info->emu, di)) > wret)
                                        wret = matchret;
                                if (!matchret) {                  /* EAZ is matching */
                                        info->isdn_driver = di;
                                        info->isdn_channel = ch;
                                        info->drv_index = idx;
                                        dev->m_idx[idx] = info->line;
                                        dev->usage[idx] &= ISDN_USAGE_EXCLUSIVE;
                                        dev->usage[idx] |= isdn_calc_usage(si1, info->emu.mdmreg[REG_L2PROT]);
                                        strcpy(dev->num[idx], nr);
                                        strcpy(info->emu.cpn, eaz);
                                        info->emu.mdmreg[REG_SI1I] = si2bit[si1];
                                        info->emu.mdmreg[REG_PLAN] = setup->plan;

                                        info->emu.mdmreg[REG_SCREEN] = setup->screen;
                                        isdn_info_update();
                                        spin_unlock_irqrestore(&dev->lock, flags);
                                        printk(KERN_INFO "isdn_tty: call from %s, -> RING on ttyI%d\n", nr,
                                               info->line);
                                        info->msr |= UART_MSR_RI;
                                        isdn_tty_modem_result(RESULT_RING, info);
                                        isdn_timer_ctrl(ISDN_TIMER_MODEMRING, 1);
                                        return 1;
                                }
                        }
                }
        }
        spin_unlock_irqrestore(&dev->lock, flags);
        printk(KERN_INFO "isdn_tty: call from %s -> %s %s\n", nr, eaz,
               ((dev->drv[di]->flags & DRV_FLAG_REJBUS) && (wret != 2)) ? "rejected" : "ignored");
        return (wret == 2) ? 3 : 0;
}

#define TTY_IS_ACTIVE(info)     (info->port.flags & ASYNC_NORMAL_ACTIVE)

int
isdn_tty_stat_callback(int i, isdn_ctrl *c)
{
        int mi;
        modem_info *info;
        char *e;

        if (i < 0)
                return 0;
        if ((mi = dev->m_idx[i]) >= 0) {
                info = &dev->mdm.info[mi];
                switch (c->command) {
                case ISDN_STAT_CINF:
                        printk(KERN_DEBUG "CHARGEINFO on ttyI%d: %ld %s\n", info->line, c->arg, c->parm.num);
                        info->emu.charge = (unsigned) simple_strtoul(c->parm.num, &e, 10);
                        if (e == (char *)c->parm.num)
                                info->emu.charge = 0;

                        break;
                case ISDN_STAT_BSENT:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_BSENT ttyI%d\n", info->line);
#endif
                        if ((info->isdn_driver == c->driver) &&
                            (info->isdn_channel == c->arg)) {
                                info->msr |= UART_MSR_CTS;
                                if (info->send_outstanding)
                                        if (!(--info->send_outstanding))
                                                info->lsr |= UART_LSR_TEMT;
                                isdn_tty_tint(info);
                                return 1;
                        }
                        break;
                case ISDN_STAT_CAUSE:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_CAUSE ttyI%d\n", info->line);
#endif
                        /* Signal cause to tty-device */
                        strncpy(info->last_cause, c->parm.num, 5);
                        return 1;
                case ISDN_STAT_DISPLAY:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_DISPLAY ttyI%d\n", info->line);
#endif
                        /* Signal display to tty-device */
                        if ((info->emu.mdmreg[REG_DISPLAY] & BIT_DISPLAY) &&
                            !(info->emu.mdmreg[REG_RESPNUM] & BIT_RESPNUM)) {
                                isdn_tty_at_cout("\r\n", info);
                                isdn_tty_at_cout("DISPLAY: ", info);
                                isdn_tty_at_cout(c->parm.display, info);
                                isdn_tty_at_cout("\r\n", info);
                        }
                        return 1;
                case ISDN_STAT_DCONN:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_DCONN ttyI%d\n", info->line);
#endif
                        if (TTY_IS_ACTIVE(info)) {
                                if (info->dialing == 1) {
                                        info->dialing = 2;
                                        return 1;
                                }
                        }
                        break;
                case ISDN_STAT_DHUP:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_DHUP ttyI%d\n", info->line);
#endif
                        if (TTY_IS_ACTIVE(info)) {
                                if (info->dialing == 1)
                                        isdn_tty_modem_result(RESULT_BUSY, info);
                                if (info->dialing > 1)
                                        isdn_tty_modem_result(RESULT_NO_CARRIER, info);
                                info->dialing = 0;
#ifdef ISDN_DEBUG_MODEM_HUP
                                printk(KERN_DEBUG "Mhup in ISDN_STAT_DHUP\n");
#endif
                                isdn_tty_modem_hup(info, 0);
                                return 1;
                        }
                        break;
                case ISDN_STAT_BCONN:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_BCONN ttyI%d\n", info->line);
#endif
                        /* Wake up any processes waiting
                         * for incoming call of this device when
                         * DCD follow the state of incoming carrier
                         */
                        if (info->port.blocked_open &&
                            (info->emu.mdmreg[REG_DCD] & BIT_DCD)) {
                                wake_up_interruptible(&info->port.open_wait);
                        }

                        /* Schedule CONNECT-Message to any tty
                         * waiting for it and
                         * set DCD-bit of its modem-status.
                         */
                        if (TTY_IS_ACTIVE(info) ||
                            (info->port.blocked_open &&
                             (info->emu.mdmreg[REG_DCD] & BIT_DCD))) {
                                info->msr |= UART_MSR_DCD;
                                info->emu.charge = 0;
                                if (info->dialing & 0xf)
                                        info->last_dir = 1;
                                else
                                        info->last_dir = 0;
                                info->dialing = 0;
                                info->rcvsched = 1;
                                if (USG_MODEM(dev->usage[i])) {
                                        if (info->emu.mdmreg[REG_L2PROT] == ISDN_PROTO_L2_MODEM) {
                                                strcpy(info->emu.connmsg, c->parm.num);
                                                isdn_tty_modem_result(RESULT_CONNECT, info);
                                        } else
                                                isdn_tty_modem_result(RESULT_CONNECT64000, info);
                                }
                                if (USG_VOICE(dev->usage[i]))
                                        isdn_tty_modem_result(RESULT_VCON, info);
                                return 1;
                        }
                        break;
                case ISDN_STAT_BHUP:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_BHUP ttyI%d\n", info->line);
#endif
                        if (TTY_IS_ACTIVE(info)) {
#ifdef ISDN_DEBUG_MODEM_HUP
                                printk(KERN_DEBUG "Mhup in ISDN_STAT_BHUP\n");
#endif
                                isdn_tty_modem_hup(info, 0);
                                return 1;
                        }
                        break;
                case ISDN_STAT_NODCH:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_NODCH ttyI%d\n", info->line);
#endif
                        if (TTY_IS_ACTIVE(info)) {
                                if (info->dialing) {
                                        info->dialing = 0;
                                        info->last_l2 = -1;
                                        info->last_si = 0;
                                        sprintf(info->last_cause, "0000");
                                        isdn_tty_modem_result(RESULT_NO_DIALTONE, info);
                                }
                                isdn_tty_modem_hup(info, 0);
                                return 1;
                        }
                        break;
                case ISDN_STAT_UNLOAD:
#ifdef ISDN_TTY_STAT_DEBUG
                        printk(KERN_DEBUG "tty_STAT_UNLOAD ttyI%d\n", info->line);
#endif
                        for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
                                info = &dev->mdm.info[i];
                                if (info->isdn_driver == c->driver) {
                                        if (info->online)
                                                isdn_tty_modem_hup(info, 1);
                                }
                        }
                        return 1;
#ifdef CONFIG_ISDN_TTY_FAX
                case ISDN_STAT_FAXIND:
                        if (TTY_IS_ACTIVE(info)) {
                                isdn_tty_fax_command(info, c);
                        }
                        break;
#endif
#ifdef CONFIG_ISDN_AUDIO
                case ISDN_STAT_AUDIO:
                        if (TTY_IS_ACTIVE(info)) {
                                switch (c->parm.num[0]) {
                                case ISDN_AUDIO_DTMF:
                                        if (info->vonline) {
                                                isdn_audio_put_dle_code(info,
                                                                        c->parm.num[1]);
                                        }
                                        break;
                                }
                        }
                        break;
#endif
                }
        }
        return 0;
}

/*********************************************************************
 Modem-Emulator-Routines
*********************************************************************/

#define cmdchar(c) ((c >= ' ') && (c <= 0x7f))

/*
 * Put a message from the AT-emulator into receive-buffer of tty,
 * convert CR, LF, and BS to values in modem-registers 3, 4 and 5.
 */
void
isdn_tty_at_cout(char *msg, modem_info *info)
{
        struct tty_port *port = &info->port;
        atemu *m = &info->emu;
        char *p;
        char c;
        u_long flags;
        struct sk_buff *skb = NULL;
        char *sp = NULL;
        int l;

        if (!msg) {
                printk(KERN_WARNING "isdn_tty: Null-Message in isdn_tty_at_cout\n");
                return;
        }

        l = strlen(msg);

        spin_lock_irqsave(&info->readlock, flags);
        if (port->flags & ASYNC_CLOSING) {
                spin_unlock_irqrestore(&info->readlock, flags);
                return;
        }

        /* use queue instead of direct, if online and */
        /* data is in queue or buffer is full */
        if (info->online && ((tty_buffer_request_room(port, l) < l) ||
                             !skb_queue_empty(&dev->drv[info->isdn_driver]->rpqueue[info->isdn_channel]))) {
                skb = alloc_skb(l, GFP_ATOMIC);
                if (!skb) {
                        spin_unlock_irqrestore(&info->readlock, flags);
                        return;
                }
                sp = skb_put(skb, l);
#ifdef CONFIG_ISDN_AUDIO
                ISDN_AUDIO_SKB_DLECOUNT(skb) = 0;
                ISDN_AUDIO_SKB_LOCK(skb) = 0;
#endif
        }

        for (p = msg; *p; p++) {
                switch (*p) {
                case '\r':
                        c = m->mdmreg[REG_CR];
                        break;
                case '\n':
                        c = m->mdmreg[REG_LF];
                        break;
                case '\b':
                        c = m->mdmreg[REG_BS];
                        break;
                default:
                        c = *p;
                }
                if (skb) {
                        *sp++ = c;
                } else {
                        if (tty_insert_flip_char(port, c, TTY_NORMAL) == 0)
                                break;
                }
        }
        if (skb) {
                __skb_queue_tail(&dev->drv[info->isdn_driver]->rpqueue[info->isdn_channel], skb);
                dev->drv[info->isdn_driver]->rcvcount[info->isdn_channel] += skb->len;
                spin_unlock_irqrestore(&info->readlock, flags);
                /* Schedule dequeuing */
                if (dev->modempoll && info->rcvsched)
                        isdn_timer_ctrl(ISDN_TIMER_MODEMREAD, 1);

        } else {
                spin_unlock_irqrestore(&info->readlock, flags);
                tty_flip_buffer_push(port);
        }
}

/*
 * Perform ATH Hangup
 */
static void
isdn_tty_on_hook(modem_info *info)
{
        if (info->isdn_channel >= 0) {
#ifdef ISDN_DEBUG_MODEM_HUP
                printk(KERN_DEBUG "Mhup in isdn_tty_on_hook\n");
#endif
                isdn_tty_modem_hup(info, 1);
        }
}

static void
isdn_tty_off_hook(void)
{
        printk(KERN_DEBUG "isdn_tty_off_hook\n");
}

#define PLUSWAIT1 (HZ / 2)      /* 0.5 sec. */
#define PLUSWAIT2 (HZ * 3 / 2)  /* 1.5 sec */

/*
 * Check Buffer for Modem-escape-sequence, activate timer-callback to
 * isdn_tty_modem_escape() if sequence found.
 *
 * Parameters:
 *   p          pointer to databuffer
 *   plus       escape-character
 *   count      length of buffer
 *   pluscount  count of valid escape-characters so far
 *   lastplus   timestamp of last character
 */
static void
isdn_tty_check_esc(const u_char *p, u_char plus, int count, int *pluscount,
                   u_long *lastplus)
{
        if (plus > 127)
                return;
        if (count > 3) {
                p += count - 3;
                count = 3;
                *pluscount = 0;
        }
        while (count > 0) {
                if (*(p++) == plus) {
                        if ((*pluscount)++) {
                                /* Time since last '+' > 0.5 sec. ? */
                                if (time_after(jiffies, *lastplus + PLUSWAIT1))
                                        *pluscount = 1;
                        } else {
                                /* Time since last non-'+' < 1.5 sec. ? */
                                if (time_before(jiffies, *lastplus + PLUSWAIT2))
                                        *pluscount = 0;
                        }
                        if ((*pluscount == 3) && (count == 1))
                                isdn_timer_ctrl(ISDN_TIMER_MODEMPLUS, 1);
                        if (*pluscount > 3)
                                *pluscount = 1;
                } else
                        *pluscount = 0;
                *lastplus = jiffies;
                count--;
        }
}

/*
 * Return result of AT-emulator to tty-receive-buffer, depending on
 * modem-register 12, bit 0 and 1.
 * For CONNECT-messages also switch to online-mode.
 * For RING-message handle auto-ATA if register 0 != 0
 */

static void
isdn_tty_modem_result(int code, modem_info *info)
{
        atemu *m = &info->emu;
        static char *msg[] =
                {"OK", "CONNECT", "RING", "NO CARRIER", "ERROR",
                 "CONNECT 64000", "NO DIALTONE", "BUSY", "NO ANSWER",
                 "RINGING", "NO MSN/EAZ", "VCON", "RUNG"};
        char s[ISDN_MSNLEN + 10];

        switch (code) {
        case RESULT_RING:
                m->mdmreg[REG_RINGCNT]++;
                if (m->mdmreg[REG_RINGCNT] == m->mdmreg[REG_RINGATA])
                        /* Automatically accept incoming call */
                        isdn_tty_cmd_ATA(info);
                break;
        case RESULT_NO_CARRIER:
#ifdef ISDN_DEBUG_MODEM_HUP
                printk(KERN_DEBUG "modem_result: NO CARRIER %d %d\n",
                       (info->port.flags & ASYNC_CLOSING),
                       (!info->port.tty));
#endif
                m->mdmreg[REG_RINGCNT] = 0;
                del_timer(&info->nc_timer);
                info->ncarrier = 0;
                if ((info->port.flags & ASYNC_CLOSING) || (!info->port.tty))
                        return;

#ifdef CONFIG_ISDN_AUDIO
                if (info->vonline & 1) {
#ifdef ISDN_DEBUG_MODEM_VOICE
                        printk(KERN_DEBUG "res3: send DLE-ETX on ttyI%d\n",
                               info->line);
#endif
                        /* voice-recording, add DLE-ETX */
                        isdn_tty_at_cout("\020\003", info);
                }
                if (info->vonline & 2) {
#ifdef ISDN_DEBUG_MODEM_VOICE
                        printk(KERN_DEBUG "res3: send DLE-DC4 on ttyI%d\n",
                               info->line);
#endif
                        /* voice-playing, add DLE-DC4 */
                        isdn_tty_at_cout("\020\024", info);
                }
#endif
                break;
        case RESULT_CONNECT:
        case RESULT_CONNECT64000:
                sprintf(info->last_cause, "0000");
                if (!info->online)
                        info->online = 2;
                break;
        case RESULT_VCON:
#ifdef ISDN_DEBUG_MODEM_VOICE
                printk(KERN_DEBUG "res3: send VCON on ttyI%d\n",
                       info->line);
#endif
                sprintf(info->last_cause, "0000");
                if (!info->online)
                        info->online = 1;
                break;
        } /* switch (code) */

        if (m->mdmreg[REG_RESP] & BIT_RESP) {
                /* Show results */
                if (m->mdmreg[REG_RESPNUM] & BIT_RESPNUM) {
                        /* Show numeric results only */
                        sprintf(s, "\r\n%d\r\n", code);
                        isdn_tty_at_cout(s, info);
                } else {
                        if (code == RESULT_RING) {
                                /* return if "show RUNG" and ringcounter>1 */
                                if ((m->mdmreg[REG_RUNG] & BIT_RUNG) &&
                                    (m->mdmreg[REG_RINGCNT] > 1))
                                        return;
                                /* print CID, _before_ _every_ ring */
                                if (!(m->mdmreg[REG_CIDONCE] & BIT_CIDONCE)) {
                                        isdn_tty_at_cout("\r\nCALLER NUMBER: ", info);
                                        isdn_tty_at_cout(dev->num[info->drv_index], info);
                                        if (m->mdmreg[REG_CDN] & BIT_CDN) {
                                                isdn_tty_at_cout("\r\nCALLED NUMBER: ", info);
                                                isdn_tty_at_cout(info->emu.cpn, info);
                                        }
                                }
                        }
                        isdn_tty_at_cout("\r\n", info);
                        isdn_tty_at_cout(msg[code], info);
                        switch (code) {
                        case RESULT_CONNECT:
                                switch (m->mdmreg[REG_L2PROT]) {
                                case ISDN_PROTO_L2_MODEM:
                                        isdn_tty_at_cout(" ", info);
                                        isdn_tty_at_cout(m->connmsg, info);
                                        break;
                                }
                                break;
                        case RESULT_RING:
                                /* Append CPN, if enabled */
                                if ((m->mdmreg[REG_CPN] & BIT_CPN)) {
                                        sprintf(s, "/%s", m->cpn);
                                        isdn_tty_at_cout(s, info);
                                }
                                /* Print CID only once, _after_ 1st RING */
                                if ((m->mdmreg[REG_CIDONCE] & BIT_CIDONCE) &&
                                    (m->mdmreg[REG_RINGCNT] == 1)) {
                                        isdn_tty_at_cout("\r\n", info);
                                        isdn_tty_at_cout("CALLER NUMBER: ", info);
                                        isdn_tty_at_cout(dev->num[info->drv_index], info);
                                        if (m->mdmreg[REG_CDN] & BIT_CDN) {
                                                isdn_tty_at_cout("\r\nCALLED NUMBER: ", info);
                                                isdn_tty_at_cout(info->emu.cpn, info);
                                        }
                                }
                                break;
                        case RESULT_NO_CARRIER:
                        case RESULT_NO_DIALTONE:
                        case RESULT_BUSY:
                        case RESULT_NO_ANSWER:
                                m->mdmreg[REG_RINGCNT] = 0;
                                /* Append Cause-Message if enabled */
                                if (m->mdmreg[REG_RESPXT] & BIT_RESPXT) {
                                        sprintf(s, "/%s", info->last_cause);
                                        isdn_tty_at_cout(s, info);
                                }
                                break;
                        case RESULT_CONNECT64000:
                                /* Append Protocol to CONNECT message */
                                switch (m->mdmreg[REG_L2PROT]) {
                                case ISDN_PROTO_L2_X75I:
                                case ISDN_PROTO_L2_X75UI:
                                case ISDN_PROTO_L2_X75BUI:
                                        isdn_tty_at_cout("/X.75", info);
                                        break;
                                case ISDN_PROTO_L2_HDLC:
                                        isdn_tty_at_cout("/HDLC", info);
                                        break;
                                case ISDN_PROTO_L2_V11096:
                                        isdn_tty_at_cout("/V110/9600", info);
                                        break;
                                case ISDN_PROTO_L2_V11019:
                                        isdn_tty_at_cout("/V110/19200", info);
                                        break;
                                case ISDN_PROTO_L2_V11038:
                                        isdn_tty_at_cout("/V110/38400", info);
                                        break;
                                }
                                if (m->mdmreg[REG_T70] & BIT_T70) {
                                        isdn_tty_at_cout("/T.70", info);
                                        if (m->mdmreg[REG_T70] & BIT_T70_EXT)
                                                isdn_tty_at_cout("+", info);
                                }
                                break;
                        }
                        isdn_tty_at_cout("\r\n", info);
                }
        }
        if (code == RESULT_NO_CARRIER) {
                if ((info->port.flags & ASYNC_CLOSING) || (!info->port.tty))
                        return;

                if (info->port.flags & ASYNC_CHECK_CD)
                        tty_hangup(info->port.tty);
        }
}


/*
 * Display a modem-register-value.
 */
static void
isdn_tty_show_profile(int ridx, modem_info *info)
{
        char v[6];

        sprintf(v, "\r\n%d", info->emu.mdmreg[ridx]);
        isdn_tty_at_cout(v, info);
}

/*
 * Get MSN-string from char-pointer, set pointer to end of number
 */
static void
isdn_tty_get_msnstr(char *n, char **p)
{
        int limit = ISDN_MSNLEN - 1;

        while (((*p[0] >= '0' && *p[0] <= '9') ||
                /* Why a comma ??? */
                (*p[0] == ',') || (*p[0] == ':')) &&
               (limit--))
                *n++ = *p[0]++;
        *n = '\0';
}

/*
 * Get phone-number from modem-commandbuffer
 */
static void
isdn_tty_getdial(char *p, char *q, int cnt)
{
        int first = 1;
        int limit = ISDN_MSNLEN - 1;    /* MUST match the size of interface var to avoid
                                           buffer overflow */

        while (strchr(" 0123456789,#.*WPTSR-", *p) && *p && --cnt > 0) {
                if ((*p >= '0' && *p <= '9') || ((*p == 'S') && first) ||
                    ((*p == 'R') && first) ||
                    (*p == '*') || (*p == '#')) {
                        *q++ = *p;
                        limit--;
                }
                if (!limit)
                        break;
                p++;
                first = 0;
        }
        *q = 0;
}

#define PARSE_ERROR { isdn_tty_modem_result(RESULT_ERROR, info); return; }
#define PARSE_ERROR1 { isdn_tty_modem_result(RESULT_ERROR, info); return 1; }

static void
isdn_tty_report(modem_info *info)
{
        atemu *m = &info->emu;
        char s[80];

        isdn_tty_at_cout("\r\nStatistics of last connection:\r\n\r\n", info);
        sprintf(s, "    Remote Number:    %s\r\n", info->last_num);
        isdn_tty_at_cout(s, info);
        sprintf(s, "    Direction:        %s\r\n", info->last_dir ? "outgoing" : "incoming");
        isdn_tty_at_cout(s, info);
        isdn_tty_at_cout("    Layer-2 Protocol: ", info);
        switch (info->last_l2) {
        case ISDN_PROTO_L2_X75I:
                isdn_tty_at_cout("X.75i", info);
                break;
        case ISDN_PROTO_L2_X75UI:
                isdn_tty_at_cout("X.75ui", info);
                break;
        case ISDN_PROTO_L2_X75BUI:
                isdn_tty_at_cout("X.75bui", info);
                break;
        case ISDN_PROTO_L2_HDLC:
                isdn_tty_at_cout("HDLC", info);
                break;
        case ISDN_PROTO_L2_V11096:
                isdn_tty_at_cout("V.110 9600 Baud", info);
                break;
        case ISDN_PROTO_L2_V11019:
                isdn_tty_at_cout("V.110 19200 Baud", info);
                break;
        case ISDN_PROTO_L2_V11038:
                isdn_tty_at_cout("V.110 38400 Baud", info);
                break;
        case ISDN_PROTO_L2_TRANS:
                isdn_tty_at_cout("transparent", info);
                break;
        case ISDN_PROTO_L2_MODEM:
                isdn_tty_at_cout("modem", info);
                break;
        case ISDN_PROTO_L2_FAX:
                isdn_tty_at_cout("fax", info);
                break;
        default:
                isdn_tty_at_cout("unknown", info);
                break;
        }
        if (m->mdmreg[REG_T70] & BIT_T70) {
                isdn_tty_at_cout("/T.70", info);
                if (m->mdmreg[REG_T70] & BIT_T70_EXT)
                        isdn_tty_at_cout("+", info);
        }
        isdn_tty_at_cout("\r\n", info);
        isdn_tty_at_cout("    Service:          ", info);
        switch (info->last_si) {
        case 1:
                isdn_tty_at_cout("audio\r\n", info);
                break;
        case 5:
                isdn_tty_at_cout("btx\r\n", info);
                break;
        case 7:
                isdn_tty_at_cout("data\r\n", info);
                break;
        default:
                sprintf(s, "%d\r\n", info->last_si);
                isdn_tty_at_cout(s, info);
                break;
        }
        sprintf(s, "    Hangup location:  %s\r\n", info->last_lhup ? "local" : "remote");
        isdn_tty_at_cout(s, info);
        sprintf(s, "    Last cause:       %s\r\n", info->last_cause);
        isdn_tty_at_cout(s, info);
}

/*
 * Parse AT&.. commands.
 */
static int
isdn_tty_cmd_ATand(char **p, modem_info *info)
{
        atemu *m = &info->emu;
        int i;
        char rb[100];

#define MAXRB (sizeof(rb) - 1)

        switch (*p[0]) {
        case 'B':
                /* &B - Set Buffersize */
                p[0]++;
                i = isdn_getnum(p);
                if ((i < 0) || (i > ISDN_SERIAL_XMIT_MAX))
                        PARSE_ERROR1;
#ifdef CONFIG_ISDN_AUDIO
                if ((m->mdmreg[REG_SI1] & 1) && (i > VBUF))
                        PARSE_ERROR1;
#endif
                m->mdmreg[REG_PSIZE] = i / 16;
                info->xmit_size = m->mdmreg[REG_PSIZE] * 16;
                switch (m->mdmreg[REG_L2PROT]) {
                case ISDN_PROTO_L2_V11096:
                case ISDN_PROTO_L2_V11019:
                case ISDN_PROTO_L2_V11038:
                        info->xmit_size /= 10;
                }
                break;
        case 'C':
                /* &C - DCD Status */
                p[0]++;
                switch (isdn_getnum(p)) {
                case 0:
                        m->mdmreg[REG_DCD] &= ~BIT_DCD;
                        break;
                case 1:
                        m->mdmreg[REG_DCD] |= BIT_DCD;
                        break;
                default:
                        PARSE_ERROR1
                                }
                break;
        case 'D':
                /* &D - Set DTR-Low-behavior */
                p[0]++;
                switch (isdn_getnum(p)) {
                case 0:
                        m->mdmreg[REG_DTRHUP] &= ~BIT_DTRHUP;
                        m->mdmreg[REG_DTRR] &= ~BIT_DTRR;
                        break;
                case 2:
                        m->mdmreg[REG_DTRHUP] |= BIT_DTRHUP;
                        m->mdmreg[REG_DTRR] &= ~BIT_DTRR;
                        break;
                case 3:
                        m->mdmreg[REG_DTRHUP] |= BIT_DTRHUP;
                        m->mdmreg[REG_DTRR] |= BIT_DTRR;
                        break;
                default:
                        PARSE_ERROR1
                                }
                break;
        case 'E':
                /* &E -Set EAZ/MSN */
                p[0]++;
                isdn_tty_get_msnstr(m->msn, p);
                break;
        case 'F':
                /* &F -Set Factory-Defaults */
                p[0]++;
                if (info->msr & UART_MSR_DCD)
                        PARSE_ERROR1;
                isdn_tty_reset_profile(m);
                isdn_tty_modem_reset_regs(info, 1);
                break;
#ifdef DUMMY_HAYES_AT
        case 'K':
                /* only for be compilant with common scripts */
                /* &K Flowcontrol - no function */
                p[0]++;
                isdn_getnum(p);
                break;
#endif
        case 'L':
                /* &L -Set Numbers to listen on */
                p[0]++;
                i = 0;
                while (*p[0] && (strchr("0123456789,-*[]?;", *p[0])) &&
                       (i < ISDN_LMSNLEN - 1))
                        m->lmsn[i++] = *p[0]++;
                m->lmsn[i] = '\0';
                break;
        case 'R':
                /* &R - Set V.110 bitrate adaption */
                p[0]++;
                i = isdn_getnum(p);
                switch (i) {
                case 0:
                        /* Switch off V.110, back to X.75 */
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_X75I;
                        m->mdmreg[REG_SI2] = 0;
                        info->xmit_size = m->mdmreg[REG_PSIZE] * 16;
                        break;
                case 9600:
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_V11096;
                        m->mdmreg[REG_SI2] = 197;
                        info->xmit_size = m->mdmreg[REG_PSIZE] * 16 / 10;
                        break;
                case 19200:
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_V11019;
                        m->mdmreg[REG_SI2] = 199;
                        info->xmit_size = m->mdmreg[REG_PSIZE] * 16 / 10;
                        break;
                case 38400:
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_V11038;
                        m->mdmreg[REG_SI2] = 198; /* no existing standard for this */
                        info->xmit_size = m->mdmreg[REG_PSIZE] * 16 / 10;
                        break;
                default:
                        PARSE_ERROR1;
                }
                /* Switch off T.70 */
                m->mdmreg[REG_T70] &= ~(BIT_T70 | BIT_T70_EXT);
                /* Set Service 7 */
                m->mdmreg[REG_SI1] |= 4;
                break;
        case 'S':
                /* &S - Set Windowsize */
                p[0]++;
                i = isdn_getnum(p);
                if ((i > 0) && (i < 9))
                        m->mdmreg[REG_WSIZE] = i;
                else
                        PARSE_ERROR1;
                break;
        case 'V':
                /* &V - Show registers */
                p[0]++;
                isdn_tty_at_cout("\r\n", info);
                for (i = 0; i < ISDN_MODEM_NUMREG; i++) {
                        sprintf(rb, "S%02d=%03d%s", i,
                                m->mdmreg[i], ((i + 1) % 10) ? " " : "\r\n");
                        isdn_tty_at_cout(rb, info);
                }
                sprintf(rb, "\r\nEAZ/MSN: %.50s\r\n",
                        strlen(m->msn) ? m->msn : "None");
                isdn_tty_at_cout(rb, info);
                if (strlen(m->lmsn)) {
                        isdn_tty_at_cout("\r\nListen: ", info);
                        isdn_tty_at_cout(m->lmsn, info);
                        isdn_tty_at_cout("\r\n", info);
                }
                break;
        case 'W':
                /* &W - Write Profile */
                p[0]++;
                switch (*p[0]) {
                case '0':
                        p[0]++;
                        modem_write_profile(m);
                        break;
                default:
                        PARSE_ERROR1;
                }
                break;
        case 'X':
                /* &X - Switch to BTX-Mode and T.70 */
                p[0]++;
                switch (isdn_getnum(p)) {
                case 0:
                        m->mdmreg[REG_T70] &= ~(BIT_T70 | BIT_T70_EXT);
                        info->xmit_size = m->mdmreg[REG_PSIZE] * 16;
                        break;
                case 1:
                        m->mdmreg[REG_T70] |= BIT_T70;
                        m->mdmreg[REG_T70] &= ~BIT_T70_EXT;
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_X75I;
                        info->xmit_size = 112;
                        m->mdmreg[REG_SI1] = 4;
                        m->mdmreg[REG_SI2] = 0;
                        break;
                case 2:
                        m->mdmreg[REG_T70] |= (BIT_T70 | BIT_T70_EXT);
                        m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_X75I;
                        info->xmit_size = 112;
                        m->mdmreg[REG_SI1] = 4;
                        m->mdmreg[REG_SI2] = 0;
                        break;
                default:
                        PARSE_ERROR1;
                }
                break;
        default:
                PARSE_ERROR1;
        }
        return 0;
}

static int
isdn_tty_check_ats(int mreg, int mval, modem_info *info, atemu *m)
{
        /* Some plausibility checks */
        switch (mreg) {
        case REG_L2PROT:
                if (mval > ISDN_PROTO_L2_MAX)
                        return 1;
                break;
        case REG_PSIZE:
                if ((mval * 16) > ISDN_SERIAL_XMIT_MAX)
                        return 1;
#ifdef CONFIG_ISDN_AUDIO
                if ((m->mdmreg[REG_SI1] & 1) && (mval > VBUFX))
                        return 1;
#endif
                info->xmit_size = mval * 16;
                switch (m->mdmreg[REG_L2PROT]) {
                case ISDN_PROTO_L2_V11096:
                case ISDN_PROTO_L2_V11019:
                case ISDN_PROTO_L2_V11038:
                        info->xmit_size /= 10;
                }
                break;
        case REG_SI1I:
        case REG_PLAN:
        case REG_SCREEN:
                /* readonly registers */
                return 1;
        }
        return 0;
}

/*
 * Perform ATS command
 */
static int
isdn_tty_cmd_ATS(char **p, modem_info *info)
{
        atemu *m = &info->emu;
        int bitpos;
        int mreg;
        int mval;
        int bval;

        mreg = isdn_getnum(p);
        if (mreg < 0 || mreg >= ISDN_MODEM_NUMREG)
                PARSE_ERROR1;
        switch (*p[0]) {
        case '=':
                p[0]++;
                mval = isdn_getnum(p);
                if (mval < 0 || mval > 255)
                        PARSE_ERROR1;
                if (isdn_tty_check_ats(mreg, mval, info, m))
                        PARSE_ERROR1;
                m->mdmreg[mreg] = mval;
                break;
        case '.':
                /* Set/Clear a single bit */
                p[0]++;
                bitpos = isdn_getnum(p);
                if ((bitpos < 0) || (bitpos > 7))
                        PARSE_ERROR1;
                switch (*p[0]) {
                case '=':
                        p[0]++;
                        bval = isdn_getnum(p);
                        if (bval < 0 || bval > 1)
                                PARSE_ERROR1;
                        if (bval)
                                mval = m->mdmreg[mreg] | (1 << bitpos);
                        else
                                mval = m->mdmreg[mreg] & ~(1 << bitpos);
                        if (isdn_tty_check_ats(mreg, mval, info, m))
                                PARSE_ERROR1;
                        m->mdmreg[mreg] = mval;
                        break;
                case '?':
                        p[0]++;
                        isdn_tty_at_cout("\r\n", info);
                        isdn_tty_at_cout((m->mdmreg[mreg] & (1 << bitpos)) ? "1" : "0",
                                         info);
                        break;
                default:
                        PARSE_ERROR1;
                }
                break;
        case '?':
                p[0]++;
                isdn_tty_show_profile(mreg, info);
                break;
        default:
                PARSE_ERROR1;
                break;
        }
        return 0;
}

/*
 * Perform ATA command
 */
static void
isdn_tty_cmd_ATA(modem_info *info)
{
        atemu *m = &info->emu;
        isdn_ctrl cmd;
        int l2;

        if (info->msr & UART_MSR_RI) {
                /* Accept incoming call */
                info->last_dir = 0;
                strcpy(info->last_num, dev->num[info->drv_index]);
                m->mdmreg[REG_RINGCNT] = 0;
                info->msr &= ~UART_MSR_RI;
                l2 = m->mdmreg[REG_L2PROT];
#ifdef CONFIG_ISDN_AUDIO
                /* If more than one bit set in reg18, autoselect Layer2 */
                if ((m->mdmreg[REG_SI1] & m->mdmreg[REG_SI1I]) != m->mdmreg[REG_SI1]) {
                        if (m->mdmreg[REG_SI1I] == 1) {
                                if ((l2 != ISDN_PROTO_L2_MODEM) && (l2 != ISDN_PROTO_L2_FAX))
                                        l2 = ISDN_PROTO_L2_TRANS;
                        } else
                                l2 = ISDN_PROTO_L2_X75I;
                }
#endif
                cmd.driver = info->isdn_driver;
                cmd.command = ISDN_CMD_SETL2;
                cmd.arg = info->isdn_channel + (l2 << 8);
                info->last_l2 = l2;
                isdn_command(&cmd);