/*
 * 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;

	tty_port_set_check_carrier(port, ~cflag & CLOCAL);
}

static int
isdn_tty_startup(modem_info *info)
{
	if (tty_port_initialized(&info->port))
		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);

	tty_port_set_initialized(&info->port, 1);
	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 (!tty_port_initialized(&info->port))
		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);

	tty_port_set_initialized(&info->port, 0);
}

/* 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_io_error(tty))
		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_io_error(tty))
		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_io_error(tty))
		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;
	}
	info->closing = 1;

	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 (tty_port_initialized(port)) {
		tty_wait_until_sent(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);
	info->closing = 0;
#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;
	tty_port_set_active(port, 0);
	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
			    tty_port_active(&info->port) &&
#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;
}

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_port_active(&info->port)) {
				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_port_active(&info->port)) {
				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_port_active(&info->port) ||
			    (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_port_active(&info->port)) {
#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_port_active(&info->port)) {
				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_port_active(&info->port)) {
				isdn_tty_fax_command(info, c);
			}
			break;
#endif
#ifdef CONFIG_ISDN_AUDIO
		case ISDN_STAT_AUDIO:
			if (tty_port_active(&info->port)) {
				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 (info->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->closing, !info->port.tty);
#endif
		m->mdmreg[REG_RINGCNT] = 0;
		del_timer(&info->nc_timer);
		info->ncarrier = 0;
		if (info->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->closing || (!info->port.tty))
			return;

		if (tty_port_check_carrier(&info->port))
			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);
		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_IN;
		}
#endif
		isdn_command(&cmd);
		cmd.driver = info->isdn_driver;
		cmd.arg = info->isdn_channel;
		cmd.command = ISDN_CMD_ACCEPTD;
		info->dialing = 16;
		info->emu.carrierwait = 0;
		isdn_command(&cmd);
		isdn_timer_ctrl(ISDN_TIMER_CARRIER, 1);
	} else
		isdn_tty_modem_result(RESULT_NO_ANSWER, info);
}

#ifdef CONFIG_ISDN_AUDIO
/*
 * Parse AT+F.. commands
 */
static int
isdn_tty_cmd_PLUSF(char **p, modem_info *info)
{
	atemu *m = &info->emu;
	char rs[20];

	if (!strncmp(p[0], "CLASS", 5)) {
		p[0] += 5;
		switch (*p[0]) {
		case '?':
			p[0]++;
			sprintf(rs, "\r\n%d",
				(m->mdmreg[REG_SI1] & 1) ? 8 : 0);
#ifdef CONFIG_ISDN_TTY_FAX
			if (TTY_IS_FCLASS2(info))
				sprintf(rs, "\r\n2");
			else if (TTY_IS_FCLASS1(info))
				sprintf(rs, "\r\n1");
#endif
			isdn_tty_at_cout(rs, info);
			break;
		case '=':
			p[0]++;
			switch (*p[0]) {
			case '0':
				p[0]++;
				m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_X75I;
				m->mdmreg[REG_L3PROT] = ISDN_PROTO_L3_TRANS;
				m->mdmreg[REG_SI1] = 4;
				info->xmit_size =
					m->mdmreg[REG_PSIZE] * 16;
				break;
#ifdef CONFIG_ISDN_TTY_FAX
			case '1':
				p[0]++;
				if (!(dev->global_features &
				      ISDN_FEATURE_L3_FCLASS1))
					PARSE_ERROR1;
				m->mdmreg[REG_SI1] = 1;
				m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_FAX;
				m->mdmreg[REG_L3PROT] = ISDN_PROTO_L3_FCLASS1;
				info->xmit_size =
					m->mdmreg[REG_PSIZE] * 16;
				break;
			case '2':
				p[0]++;
				if (!(dev->global_features &
				      ISDN_FEATURE_L3_FCLASS2))
					PARSE_ERROR1;
				m->mdmreg[REG_SI1] = 1;
				m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_FAX;
				m->mdmreg[REG_L3PROT] = ISDN_PROTO_L3_FCLASS2;
				info->xmit_size =
					m->mdmreg[REG_PSIZE] * 16;
				break;
#endif
			case '8':
				p[0]++;
				/* L2 will change on dialout with si=1 */
				m->mdmreg[REG_L2PROT] = ISDN_PROTO_L2_X75I;
				m->mdmreg[REG_L3PROT] = ISDN_PROTO_L3_TRANS;
				m->mdmreg[REG_SI1] = 5;
				info->xmit_size = VBUF;
				break;
			case '?':
				p[0]++;
				strcpy(rs, "\r\n0,");
#ifdef CONFIG_ISDN_TTY_FAX
				if (dev->global_features &
				    ISDN_FEATURE_L3_FCLASS1)
					strcat(rs, "1,");
				if (dev->global_features &
				    ISDN_FEATURE_L3_FCLASS2)
					strcat(rs, "2,");
#endif
				strcat(rs, "8");
				isdn_tty_at_cout(rs, info);
				break;
			default:
				PARSE_ERROR1;
			}
			break;
		default:
			PARSE_ERROR1;
		}
		return 0;
	}
#ifdef CONFIG_ISDN_TTY_FAX
	return (isdn_tty_cmd_PLUSF_FAX(p, info));
#else
	PARSE_ERROR1;
#endif
}

/*
 * Parse AT+V.. commands
 */
static int
isdn_tty_cmd_PLUSV(char **p, modem_info *info)
{
	atemu *m = &info->emu;
	isdn_ctrl cmd;
	static char *vcmd[] =
		{"NH", "IP", "LS", "RX", "SD", "SM", "TX", "DD", NULL};
	int i;
	int par1;
	int par2;
	char rs[20];

	i = 0;
	while (vcmd[i]) {
		if (!strncmp(vcmd[i], p[0], 2)) {
			p[0] += 2;
			break;
		}
		i++;
	}
	switch (i) {
	case 0:
		/* AT+VNH - Auto hangup feature */
		switch (*p[0]) {
		case '?':
			p[0]++;
			isdn_tty_at_cout("\r\n1", info);
			break;
		case '=':
			p[0]++;
			switch (*p[0]) {
			case '1':
				p[0]++;
				break;
			case '?':
				p[0]++;
				isdn_tty_at_cout("\r\n1", info);
				break;
			default:
				PARSE_ERROR1;
			}
			break;
		default:
			PARSE_ERROR1;
		}
		break;
	case 1:
		/* AT+VIP - Reset all voice parameters */
		isdn_tty_modem_reset_vpar(m);
		break;
	case 2:
		/* AT+VLS - Select device, accept incoming call */
		switch (*p[0]) {
		case '?':
			p[0]++;
			sprintf(rs, "\r\n%d", m->vpar[0]);
			isdn_tty_at_cout(rs, info);
			break;
		case '=':
			p[0]++;
			switch (*p[0]) {
			case '0':
				p[0]++;
				m->vpar[0] = 0;
				break;
			case '2':
				p[0]++;
				m->vpar[0] = 2;
				break;
			case '?':
				p[0]++;
				isdn_tty_at_cout("\r\n0,2", info);
				break;
			default:
				PARSE_ERROR1;
			}
			break;
		default:
			PARSE_ERROR1;
		}
		break;
	case 3:
		/* AT+VRX - Start recording */
		if (!m->vpar[0])
			PARSE_ERROR1;
		if (info->online != 1) {
			isdn_tty_modem_result(RESULT_NO_ANSWER, info);
			return 1;
		}
		info->dtmf_state = isdn_audio_dtmf_init(info->dtmf_state);
		if (!info->dtmf_state) {
			printk(KERN_WARNING "isdn_tty: Couldn't malloc dtmf state\n");
			PARSE_ERROR1;
		}
		info->silence_state = isdn_audio_silence_init(info->silence_state);
		if (!info->silence_state) {
			printk(KERN_WARNING "isdn_tty: Couldn't malloc silence state\n");
			PARSE_ERROR1;
		}
		if (m->vpar[3] < 5) {
			info->adpcmr = isdn_audio_adpcm_init(info->adpcmr, m->vpar[3]);
			if (!info->adpcmr) {
				printk(KERN_WARNING "isdn_tty: Couldn't malloc adpcm state\n");
				PARSE_ERROR1;
			}
		}
#ifdef ISDN_DEBUG_AT
		printk(KERN_DEBUG "AT: +VRX\n");
#endif
		info->vonline |= 1;
		isdn_tty_modem_result(RESULT_CONNECT, info);
		return 0;
		break;
	case 4:
		/* AT+VSD - Silence detection */
		switch (*p[0]) {
		case '?':
			p[0]++;
			sprintf(rs, "\r\n<%d>,<%d>",
				m->vpar[1],
				m->vpar[2]);
			isdn_tty_at_cout(rs, info);
			break;
		case '=':
			p[0]++;
			if ((*p[0] >= '0') && (*p[0] <= '9')) {
				par1 = isdn_getnum(p);
				if ((par1 < 0) || (par1 > 31))
					PARSE_ERROR1;
				if (*p[0] != ',')
					PARSE_ERROR1;
				p[0]++;
				par2 = isdn_getnum(p);
				if ((par2 < 0) || (par2 > 255))
					PARSE_ERROR1;
				m->vpar[1] = par1;
				m->vpar[2] = par2;
				break;
			} else
				if (*p[0] == '?') {
					p[0]++;
					isdn_tty_at_cout("\r\n<0-31>,<0-255>",
							 info);
					break;
				} else
					PARSE_ERROR1;
			break;
		default:
			PARSE_ERROR1;
		}
		break;
	case 5:
		/* AT+VSM - Select compression */
		switch (*p[0]) {
		case '?':
			p[0]++;
			sprintf(rs, "\r\n<%d>,<%d><8000>",
				m->vpar[3],
				m->vpar[1]);
			isdn_tty_at_cout(rs, info);
			break;
		case '=':
			p[0]++;
			switch (*p[0]) {
			case '2':
			case '3':
			case '4':
			case '5':
			case '6':
				par1 = isdn_getnum(p);
				if ((par1 < 2) || (par1 > 6))
					PARSE_ERROR1;
				m->vpar[3] = par1;
				break;
			case '?':
				p[0]++;
				isdn_tty_at_cout("\r\n2;ADPCM;2;0;(8000)\r\n",
						 info);
				isdn_tty_at_cout("3;ADPCM;3;0;(8000)\r\n",
						 info);
				isdn_tty_at_cout("4;ADPCM;4;0;(8000)\r\n",
						 info);
				isdn_tty_at_cout("5;ALAW;8;0;(8000)\r\n",
						 info);
				isdn_tty_at_cout("6;ULAW;8;0;(8000)\r\n",
						 info);
				break;
			default:
				PARSE_ERROR1;
			}
			break;
		default:
			PARSE_ERROR1;
		}
		break;
	case 6:
		/* AT+VTX - Start sending */
		if (!m->vpar[0])
			PARSE_ERROR1;
		if (info->online != 1) {
			isdn_tty_modem_result(RESULT_NO_ANSWER, info);
			return 1;
		}
		info->dtmf_state = isdn_audio_dtmf_init(info->dtmf_state);
		if (!info->dtmf_state) {
			printk(KERN_WARNING "isdn_tty: Couldn't malloc dtmf state\n");
			PARSE_ERROR1;
		}
		if (m->vpar[3] < 5) {
			info->adpcms = isdn_audio_adpcm_init(info->adpcms, m->vpar[3]);
			if (!info->adpcms) {
				printk(KERN_WARNING "isdn_tty: Couldn't malloc adpcm state\n");
				PARSE_ERROR1;
			}
		}
#ifdef ISDN_DEBUG_AT
		printk(KERN_DEBUG "AT: +VTX\n");
#endif
		m->lastDLE = 0;
		info->vonline |= 2;
		isdn_tty_modem_result(RESULT_CONNECT, info);
		return 0;
		break;
	case 7:
		/* AT+VDD - DTMF detection */
		switch (*p[0]) {
		case '?':
			p[0]++;
			sprintf(rs, "\r\n<%d>,<%d>",
				m->vpar[4],
				m->vpar[5]);
			isdn_tty_at_cout(rs, info);
			break;
		case '=':
			p[0]++;
			if ((*p[0] >= '0') && (*p[0] <= '9')) {
				if (info->online != 1)
					PARSE_ERROR1;
				par1 = isdn_getnum(p);
				if ((par1 < 0) || (par1 > 15))
					PARSE_ERROR1;
				if (*p[0] != ',')
					PARSE_ERROR1;
				p[0]++;
				par2 = isdn_getnum(p);
				if ((par2 < 0) || (par2 > 255))
					PARSE_ERROR1;
				m->vpar[4] = par1;
				m->vpar[5] = par2;
				cmd.driver = info->isdn_driver;
				cmd.command = ISDN_CMD_AUDIO;
				cmd.arg = info->isdn_channel + (ISDN_AUDIO_SETDD << 8);
				cmd.parm.num[0] = par1;
				cmd.parm.num[1] = par2;
				isdn_command(&cmd);
				break;
			} else
				if (*p[0] == '?') {
					p[0]++;
					isdn_tty_at_cout("\r\n<0-15>,<0-255>",
							 info);
					break;
				} else
					PARSE_ERROR1;
			break;
		default:
			PARSE_ERROR1;
		}
		break;
	default:
		PARSE_ERROR1;
	}
	return 0;
}
#endif                          /* CONFIG_ISDN_AUDIO */

/*
 * Parse and perform an AT-command-line.
 */
static void
isdn_tty_parse_at(modem_info *info)
{
	atemu *m = &info->emu;
	char *p;
	char ds[ISDN_MSNLEN];

#ifdef ISDN_DEBUG_AT
	printk(KERN_DEBUG "AT: '%s'\n", m->mdmcmd);
#endif
	for (p = &m->mdmcmd[2]; *p;) {
		switch (*p) {
		case ' ':
			p++;
			break;
		case 'A':
			/* A - Accept incoming call */
			p++;
			isdn_tty_cmd_ATA(info);
			return;
		case 'D':
			/* D - Dial */
			if (info->msr & UART_MSR_DCD)
				PARSE_ERROR;
			if (info->msr & UART_MSR_RI) {
				isdn_tty_modem_result(RESULT_NO_CARRIER, info);
				return;
			}
			isdn_tty_getdial(++p, ds, sizeof ds);
			p += strlen(p);
			if (!strlen(m->msn))
				isdn_tty_modem_result(RESULT_NO_MSN_EAZ, info);
			else if (strlen(ds))
				isdn_tty_dial(ds, info, m);
			else
				PARSE_ERROR;
			return;
		case 'E':
			/* E - Turn Echo on/off */
			p++;
			switch (isdn_getnum(&p)) {
			case 0:
				m->mdmreg[REG_ECHO] &= ~BIT_ECHO;
				break;
			case 1:
				m->mdmreg[REG_ECHO] |= BIT_ECHO;
				break;
			default:
				PARSE_ERROR;
			}
			break;
		case 'H':
			/* H - On/Off-hook */
			p++;
			switch (*p) {
			case '0':
				p++;
				isdn_tty_on_hook(info);
				break;
			case '1':
				p++;
				isdn_tty_off_hook();
				break;
			default:
				isdn_tty_on_hook(info);
				break;
			}
			break;
		case 'I':
			/* I - Information */
			p++;
			isdn_tty_at_cout("\r\nLinux ISDN", info);
			switch (*p) {
			case '0':
			case '1':
				p++;
				break;
			case '2':
				p++;
				isdn_tty_report(info);
				break;
			case '3':
				p++;
				snprintf(ds, sizeof(ds), "\r\n%d", info->emu.charge);
				isdn_tty_at_cout(ds, info);
				break;
			default:;
			}
			break;
#ifdef DUMMY_HAYES_AT
		case 'L':
		case 'M':
			/* only for be compilant with common scripts */
			/* no function */
			p++;
			isdn_getnum(&p);
			break;
#endif
		case 'O':
			/* O - Go online */
			p++;
			if (info->msr & UART_MSR_DCD)
				/* if B-Channel is up */
				isdn_tty_modem_result((m->mdmreg[REG_L2PROT] == ISDN_PROTO_L2_MODEM) ? RESULT_CONNECT : RESULT_CONNECT64000, info);
			else
				isdn_tty_modem_result(RESULT_NO_CARRIER, info);
			return;
		case 'Q':
			/* Q - Turn Emulator messages on/off */
			p++;
			switch (isdn_getnum(&p)) {
			case 0:
				m->mdmreg[REG_RESP] |= BIT_RESP;
				break;
			case 1:
				m->mdmreg[REG_RESP] &= ~BIT_RESP;
				break;
			default:
				PARSE_ERROR;
			}
			break;
		case 'S':
			/* S - Set/Get Register */
			p++;
			if (isdn_tty_cmd_ATS(&p, info))
				return;
			break;
		case 'V':
			/* V - Numeric or ASCII Emulator-messages */
			p++;
			switch (isdn_getnum(&p)) {
			case 0:
				m->mdmreg[REG_RESP] |= BIT_RESPNUM;
				break;
			case 1:
				m->mdmreg[REG_RESP] &= ~BIT_RESPNUM;
				break;
			default:
				PARSE_ERROR;
			}
			break;
		case 'Z':
			/* Z - Load Registers from Profile */
			p++;
			if (info->msr & UART_MSR_DCD) {
				info->online = 0;
				isdn_tty_on_hook(info);
			}
			isdn_tty_modem_reset_regs(info, 1);
			break;
		case '+':
			p++;
			switch (*p) {
#ifdef CONFIG_ISDN_AUDIO
			case 'F':
				p++;
				if (isdn_tty_cmd_PLUSF(&p, info))
					return;
				break;
			case 'V':
				if ((!(m->mdmreg[REG_SI1] & 1)) ||
				    (m->mdmreg[REG_L2PROT] == ISDN_PROTO_L2_MODEM))
					PARSE_ERROR;
				p++;
				if (isdn_tty_cmd_PLUSV(&p, info))
					return;
				break;
#endif                          /* CONFIG_ISDN_AUDIO */
			case 'S':	/* SUSPEND */
				p++;
				isdn_tty_get_msnstr(ds, &p);
				isdn_tty_suspend(ds, info, m);
				break;
			case 'R':	/* RESUME */
				p++;
				isdn_tty_get_msnstr(ds, &p);
				isdn_tty_resume(ds, info, m);
				break;
			case 'M':	/* MESSAGE */
				p++;
				isdn_tty_send_msg(info, m, p);
				break;
			default:
				PARSE_ERROR;
			}
			break;
		case '&':
			p++;
			if (isdn_tty_cmd_ATand(&p, info))
				return;
			break;
		default:
			PARSE_ERROR;
		}
	}
#ifdef CONFIG_ISDN_AUDIO
	if (!info->vonline)
#endif
		isdn_tty_modem_result(RESULT_OK, info);
}

/* Need own toupper() because standard-toupper is not available
 * within modules.
 */
#define my_toupper(c) (((c >= 'a') && (c <= 'z')) ? (c & 0xdf) : c)

/*
 * Perform line-editing of AT-commands
 *
 * Parameters:
 *   p        inputbuffer
 *   count    length of buffer
 *   channel  index to line (minor-device)
 */
static int
isdn_tty_edit_at(const char *p, int count, modem_info *info)
{
	atemu *m = &info->emu;
	int total = 0;
	u_char c;
	char eb[2];
	int cnt;

	for (cnt = count; cnt > 0; p++, cnt--) {
		c = *p;
		total++;
		if (c == m->mdmreg[REG_CR] || c == m->mdmreg[REG_LF]) {
			/* Separator (CR or LF) */
			m->mdmcmd[m->mdmcmdl] = 0;
			if (m->mdmreg[REG_ECHO] & BIT_ECHO) {
				eb[0] = c;
				eb[1] = 0;
				isdn_tty_at_cout(eb, info);
			}
			if ((m->mdmcmdl >= 2) && (!(strncmp(m->mdmcmd, "AT", 2))))
				isdn_tty_parse_at(info);
			m->mdmcmdl = 0;
			continue;
		}
		if (c == m->mdmreg[REG_BS] && m->mdmreg[REG_BS] < 128) {
			/* Backspace-Function */
			if ((m->mdmcmdl > 2) || (!m->mdmcmdl)) {
				if (m->mdmcmdl)
					m->mdmcmdl--;
				if (m->mdmreg[REG_ECHO] & BIT_ECHO)
					isdn_tty_at_cout("\b", info);
			}
			continue;
		}
		if (cmdchar(c)) {
			if (m->mdmreg[REG_ECHO] & BIT_ECHO) {
				eb[0] = c;
				eb[1] = 0;
				isdn_tty_at_cout(eb, info);
			}
			if (m->mdmcmdl < 255) {
				c = my_toupper(c);
				switch (m->mdmcmdl) {
				case 1:
					if (c == 'T') {
						m->mdmcmd[m->mdmcmdl] = c;
						m->mdmcmd[++m->mdmcmdl] = 0;
						break;
					} else
						m->mdmcmdl = 0;
					/* Fall through, check for 'A' */
				case 0:
					if (c == 'A') {
						m->mdmcmd[m->mdmcmdl] = c;
						m->mdmcmd[++m->mdmcmdl] = 0;
					}
					break;
				default:
					m->mdmcmd[m->mdmcmdl] = c;
					m->mdmcmd[++m->mdmcmdl] = 0;
				}
			}
		}
	}
	return total;
}

/*
 * Switch all modem-channels who are online and got a valid
 * escape-sequence 1.5 seconds ago, to command-mode.
 * This function is called every second via timer-interrupt from within
 * timer-dispatcher isdn_timer_function()
 */
void
isdn_tty_modem_escape(void)
{
	int ton = 0;
	int i;
	int midx;

	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
		if (USG_MODEM(dev->usage[i]) && (midx = dev->m_idx[i]) >= 0) {
			modem_info *info = &dev->mdm.info[midx];
			if (info->online) {
				ton = 1;
				if ((info->emu.pluscount == 3) &&
				    time_after(jiffies,
					    info->emu.lastplus + PLUSWAIT2)) {
					info->emu.pluscount = 0;
					info->online = 0;
					isdn_tty_modem_result(RESULT_OK, info);
				}
			}
		}
	isdn_timer_ctrl(ISDN_TIMER_MODEMPLUS, ton);
}

/*
 * Put a RING-message to all modem-channels who have the RI-bit set.
 * This function is called every second via timer-interrupt from within
 * timer-dispatcher isdn_timer_function()
 */
void
isdn_tty_modem_ring(void)
{
	int ton = 0;
	int i;

	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
		modem_info *info = &dev->mdm.info[i];
		if (info->msr & UART_MSR_RI) {
			ton = 1;
			isdn_tty_modem_result(RESULT_RING, info);
		}
	}
	isdn_timer_ctrl(ISDN_TIMER_MODEMRING, ton);
}

/*
 * For all online tty's, try sending data to
 * the lower levels.
 */
void
isdn_tty_modem_xmit(void)
{
	int ton = 1;
	int i;

	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
		modem_info *info = &dev->mdm.info[i];
		if (info->online) {
			ton = 1;
			isdn_tty_senddown(info);
			isdn_tty_tint(info);
		}
	}
	isdn_timer_ctrl(ISDN_TIMER_MODEMXMIT, ton);
}

/*
 * Check all channels if we have a 'no carrier' timeout.
 * Timeout value is set by Register S7.
 */
void
isdn_tty_carrier_timeout(void)
{
	int ton = 0;
	int i;

	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
		modem_info *info = &dev->mdm.info[i];
		if (!info->dialing)
			continue;
		if (info->emu.carrierwait++ > info->emu.mdmreg[REG_WAITC]) {
			info->dialing = 0;
			isdn_tty_modem_result(RESULT_NO_CARRIER, info);
			isdn_tty_modem_hup(info, 1);
		} else
			ton = 1;
	}
	isdn_timer_ctrl(ISDN_TIMER_CARRIER, ton);
}