# isdn_tty.c

    /* $Id$

     * Linux ISDN subsystem, tty functions and AT-command emulator (linklevel).
     *
     * Copyright 1994,95,96 by Fritz Elfert (fritz@wuemaus.franken.de)
     * Copyright 1995,96    by Thinking Objects Software GmbH Wuerzburg
     *
     * This program is free software; you can redistribute it and/or modify
     * it under the terms of the GNU General Public License as published by
     * the Free Software Foundation; either version 2, or (at your option)
     * any later version.
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
     *
     * $Log$
     * Revision 1.57  1998/06/26 15:12:36  fritz
     * Added handling of STAT_ICALL with incomplete CPN.
     * Added AT&L for ttyI emulator.
     * Added more locking stuff in tty_write.
     *
     * Revision 1.56  1998/06/18 23:31:51  fritz
     * Replaced cli()/restore_flags() in isdn_tty_write() by locking.
     * Removed direct-senddown feature in isdn_tty_write because it will
     * never succeed with locking and is useless anyway.
     *
     * Revision 1.55  1998/06/17 19:50:55  he
     * merged with 2.1.10[34] (cosmetics and udelay() -> mdelay())
     * brute force fix to avoid Ugh's in isdn_tty_write()
     * cleaned up some dead code
     *
     * Revision 1.54  1998/06/07 00:20:13  fritz
     * abc cleanup.
     *
     * Revision 1.53  1998/06/02 12:10:16  detabc
     * wegen einer einstweiliger verfuegung gegen DW ist zur zeit
     * die abc-extension bis zur klaerung der rechtslage nicht verfuegbar
     *
     * Revision 1.52  1998/03/19 13:18:21  keil
     * Start of a CAPI like interface for supplementary Service
     * first service: SUSPEND
     *
     * Revision 1.51  1998/03/08 14:26:11  detabc
     * change kfree_skb to dev_kfree_skb
     * remove SET_SKB_FREE
     *
     * Revision 1.50  1998/03/08 13:14:28  detabc
     * abc-extension support for kernels > 2.1.x
     * first try (sorry experimental)
     *
     * Revision 1.49  1998/03/08 00:01:59  fritz
     * Bugfix: Lowlevel module usage and channel usage were not
     *         reset on NO DCHANNEL.
     *
     * Revision 1.48  1998/03/07 12:28:15  tsbogend
     * fixed kernel unaligned traps on Linux/Alpha
     *
     * Revision 1.47  1998/02/22 19:44:14  fritz
     * Bugfixes and improvements regarding V.110, V.110 now running.
     *
     * Revision 1.46  1998/02/20 17:23:08  fritz
     * Changes for recent kernels.
     * Merged in contributions by Thomas Pfeiffer (V.110 T.70+ Extended FAX stuff)
     * Added symbolic constants for Modem-Registers.
     *
     * Revision 1.45  1998/01/31 22:07:49  keil
     * changes for newer kernels
     *
     * Revision 1.44  1998/01/31 19:30:02  calle
     * Merged changes from and for 2.1.82, not tested only compiled ...
     *
     * Revision 1.43  1997/10/09 21:29:04  fritz
     * New HL<->LL interface:
     *   New BSENT callback with nr. of bytes included.
     *   Sending without ACK.
     *   New L1 error status (not yet in use).
     *   Cleaned up obsolete structures.
     * Implemented Cisco-SLARP.
     * Changed local net-interface data to be dynamically allocated.
     * Removed old 2.0 compatibility stuff.
     *
     * Revision 1.42  1997/10/01 09:20:49  fritz
     * Removed old compatibility stuff for 2.0.X kernels.
     * From now on, this code is for 2.1.X ONLY!
     * Old stuff is still in the separate branch.
     *
     * Revision 1.41  1997/05/27 15:17:31  fritz
     * Added changes for recent 2.1.x kernels:
     *   changed return type of isdn_close
     *   queue_task_* -> queue_task
     *   clear/set_bit -> test_and_... where apropriate.
     *   changed type of hard_header_cache parameter.
     *
     * Revision 1.40  1997/03/24 22:55:27  fritz
     * Added debug code for status callbacks.
     *
     * Revision 1.39  1997/03/21 18:25:56  fritz
     * Corrected CTS handling.
     *
     * Revision 1.38  1997/03/07 12:13:35  fritz
     * Bugfix: Send audio in adpcm format was broken.
     * Bugfix: CTS handling was wrong.
     *
     * Revision 1.37  1997/03/07 01:37:34  fritz
     * Bugfix: Did not compile with CONFIG_ISDN_AUDIO disabled.
     * Bugfix: isdn_tty_tint() did not handle lowlevel errors correctly.
     * Bugfix: conversion was wrong when sending ulaw audio.
     * Added proper ifdef's for CONFIG_ISDN_AUDIO
     *
     * Revision 1.36  1997/03/04 21:41:55  fritz
     * Fix: Excessive stack usage of isdn_tty_senddown()
     *      and isdn_tty_end_vrx() could lead to problems.
     *
     * Revision 1.35  1997/03/02 19:05:52  fritz
     * Bugfix: Avoid recursion.
     *
     * Revision 1.34  1997/03/02 14:29:22  fritz
     * More ttyI related cleanup.
     *
     * Revision 1.33  1997/02/28 02:32:45  fritz
     * Cleanup: Moved some tty related stuff from isdn_common.c
     *          to isdn_tty.c
     * Bugfix:  Bisync protocol did not behave like documented.
     *
     * Revision 1.32  1997/02/23 15:43:03  fritz
     * Small change in handling of incoming calls
     * documented in newest version of ttyI.4
     *
     * Revision 1.31  1997/02/21 13:05:57  fritz
     * Bugfix: Remote hangup did not set location-info on ttyI's
     *
     * Revision 1.30  1997/02/18 09:41:05  fritz
     * Added support for bitwise access to modem registers (ATSx.y=n, ATSx.y?).
     * Beautified output of AT&V.
     *
     * Revision 1.29  1997/02/16 12:11:51  fritz
     * Added S13,Bit4 option.
     *
     * Revision 1.28  1997/02/10 22:07:08  fritz
     * Added 2 modem registers for numbering plan and screening info.
     *
     * Revision 1.27  1997/02/10 21:31:14  fritz
     * Changed setup-interface (incoming and outgoing).
     *
     * Revision 1.26  1997/02/10 20:12:48  fritz
     * Changed interface for reporting incoming calls.
     *
     * Revision 1.25  1997/02/03 23:04:30  fritz
     * Reformatted according CodingStyle.
     * skb->free stuff replaced by macro.
     * Finished full-duplex audio.
     *
     * Revision 1.24  1997/01/14 01:32:42  fritz
     * Changed audio receive not to rely on skb->users and skb->lock.
     * Added ATI2 and related variables.
     * Started adding full-duplex audio capability.
     *
     * Revision 1.23  1996/10/22 23:14:02  fritz
     * Changes for compatibility to 2.0.X and 2.1.X kernels.
     *
     * Revision 1.22  1996/10/19 18:56:43  fritz
     * ATZ did not change the xmitbuf size.
     *
     * Revision 1.21  1996/06/24 17:40:28  fritz
     * Bugfix: Did not compile without CONFIG_ISDN_AUDIO
     *
     * Revision 1.20  1996/06/15 14:59:39  fritz
     * Fixed isdn_tty_tint() to handle partially sent
     * sk_buffs.
     *
     * Revision 1.19  1996/06/12 15:53:56  fritz
     * Bugfix: AT+VTX and AT+VRX could be executed without
     *         having a connection.
     *         Missing check for NULL tty in isdn_tty_flush_buffer().
     *
     * Revision 1.18  1996/06/07 11:17:33  tsbogend
     * added missing #ifdef CONFIG_ISDN_AUDIO to make compiling without
     * audio support possible
     *
     * Revision 1.17  1996/06/06 14:55:47  fritz
     * Changed to support DTMF decoding on audio playback also.
     * Bugfix: Added check for invalid info->isdn_driver in
     *         isdn_tty_senddown().
     * Clear ncarrier flag on last close() of a tty.
     *
     * Revision 1.16  1996/06/05 02:24:12  fritz
     * Added DTMF decoder for audio mode.
     *
     * Revision 1.15  1996/06/03 20:35:01  fritz
     * Fixed typos.
     *
     * Revision 1.14  1996/06/03 20:12:19  fritz
     * Fixed typos.
     * Added call to write_wakeup via isdn_tty_flush_buffer()
     * in isdn_tty_modem_hup().
     *
     * Revision 1.13  1996/05/31 01:33:29  fritz
     * Changed buffering due to bad performance with mgetty.
     * Now sk_buff is delayed allocated in isdn_tty_senddown
     * using xmit_buff like in standard serial driver.
     * Fixed module locking.
     * Added DLE-DC4 handling in voice mode.
     *
     * Revision 1.12  1996/05/19 01:34:40  fritz
     * Bugfix: ATS returned error.
     *         Register 20 made readonly.
     *
     * Revision 1.11  1996/05/18 01:37:03  fritz
     * Added spelling corrections and some minor changes
     * to stay in sync with kernel.
     *
     * Revision 1.10  1996/05/17 03:51:49  fritz
     * Changed DLE handling for audio receive.
     *
     * Revision 1.9  1996/05/11 21:52:07  fritz
     * Changed queue management to use sk_buffs.
     *
     * Revision 1.8  1996/05/10 08:49:43  fritz
     * Checkin before major changes of tty-code.
     *
     * Revision 1.7  1996/05/07 09:15:09  fritz
     * Reorganized and general cleanup.
     * Bugfixes:
     *  - Audio-transmit working now.
     *  - "NO CARRIER" now reported, when hanging up with DTR low.
     *  - Corrected CTS handling.
     *
     * Revision 1.6  1996/05/02 03:59:25  fritz
     * Bugfixes:
     *  - On dialout, layer-2 setup had been incomplete
     *    when using new auto-layer2 feature.
     *  - On hangup, "NO CARRIER" message sometimes missing.
     *
     * Revision 1.5  1996/04/30 21:05:25  fritz
     * Test commit
     *
     * Revision 1.4  1996/04/20 16:39:54  fritz
     * Changed all io to go through generic routines in isdn_common.c
     * Fixed a real ugly bug in modem-emulator: 'ATA' had been accepted
     * even when a call has been cancelled from the remote machine.
     *
     * Revision 1.3  1996/02/11 02:12:32  fritz
     * Bugfixes according to similar fixes in standard serial.c of kernel.
     *
     * Revision 1.2  1996/01/22 05:12:25  fritz
     * replaced my_atoi by simple_strtoul
     *
     * Revision 1.1  1996/01/09 04:13:18  fritz
     * Initial revision
     *
     */
    #undef ISDN_TTY_STAT_DEBUG

    #define __NO_VERSION__
    #include <linux/config.h>
    #include <linux/module.h>
    #include <linux/isdn.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

    /* Prototypes */

    static int isdn_tty_edit_at(const char *, int, modem_info *, int);
    static void isdn_tty_check_esc(const u_char *, u_char, int, int *, int *, int);
    static void isdn_tty_modem_reset_regs(modem_info *, int);
    static void isdn_tty_cmd_ATA(modem_info *);
    static void isdn_tty_at_cout(char *, 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 char *isdn_ttyname_ttyI = "ttyI";
    static char *isdn_ttyname_cui = "cui";
    static int bit2si[8] =
    {1, 5, 7, 7, 7, 7, 7, 7};
    static int si2bit[8] =
    {4, 1, 4, 4, 4, 4, 4, 4};

    char *isdn_tty_revision = "$Revision$";

    #define DLE 0x10
    #define ETX 0x03
    #define DC4 0x14

    /*
     * Definition of some special Registers of AT-Emulator
     */
    #define REG_RINGATA   0
    #define REG_RINGCNT   1
    #define REG_ESC       2
    #define REG_CR        3
    #define REG_LF        4
    #define REG_BS        5

    #define REG_RESP     12
    #define BIT_RESP      1
    #define REG_RESPNUM  12
    #define BIT_RESPNUM   2
    #define REG_ECHO     12
    #define BIT_ECHO      4
    #define REG_DCD      12
    #define BIT_DCD       8
    #define REG_CTS      12
    #define BIT_CTS      16
    #define REG_DTRR     12
    #define BIT_DTRR     32
    #define REG_DSR      12
    #define BIT_DSR      64
    #define REG_CPPP     12
    #define BIT_CPPP    128

    #define REG_T70      13
    #define BIT_T70       2
    #define BIT_T70_EXT  32
    #define REG_DTRHUP   13
    #define BIT_DTRHUP    4
    #define REG_RESPXT   13
    #define BIT_RESPXT    8
    #define REG_CIDONCE  13
    #define BIT_CIDONCE  16
    #define REG_RUNG     13
    #define BIT_RUNG     64
    #define REG_RESRXT   13
    #define BIT_RESRXT  128

    #define REG_L2PROT   14
    #define REG_L3PROT   15
    #define REG_PSIZE    16
    #define REG_WSIZE    17
    #define REG_SI1      18
    #define REG_SI2      19
    #define REG_SI1I     20
    #define REG_PLAN     21
    #define REG_SCREEN   22

    /* 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)
    {
    	int c;
    	int len;
    	struct tty_struct *tty;

    	if (info->online) {
    		if ((tty = info->tty)) {
    			if (info->mcr & UART_MCR_RTS) {
    				c = TTY_FLIPBUF_SIZE - tty->flip.count;
    				len = skb->len
    #ifdef CONFIG_ISDN_AUDIO
    					+ ISDN_AUDIO_SKB_DLECOUNT(skb)
    #endif
    					;
    				if (c >= len) {
    #ifdef CONFIG_ISDN_AUDIO
    					if (ISDN_AUDIO_SKB_DLECOUNT(skb))
    						while (skb->len--) {
    							if (*skb->data == DLE)
    								tty_insert_flip_char(tty, DLE, 0);
    							tty_insert_flip_char(tty, *skb->data++, 0);
    					} else {
    #endif
    						memcpy(tty->flip.char_buf_ptr,
    						       skb->data, len);
    						tty->flip.count += len;
    						tty->flip.char_buf_ptr += len;
    						memset(tty->flip.flag_buf_ptr, 0, len);
    						tty->flip.flag_buf_ptr += len;
    #ifdef CONFIG_ISDN_AUDIO
    					}
    #endif
    					if (info->emu.mdmreg[REG_CPPP] & BIT_CPPP)
    						tty->flip.flag_buf_ptr[len - 1] = 0xff;
    					queue_task(&tty->flip.tqueue, &tq_timer);
    					kfree_skb(skb);
    					return 1;
    				}
    			}
    		}
    	}
    	return 0;
    }

    /* 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 c;
    	int r;
    	ulong flags;
    	struct tty_struct *tty;
    	modem_info *info;

    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		if ((midx = dev->m_idx[i]) >= 0) {
    			info = &dev->mdm.info[midx];
    			if (info->online) {
    				r = 0;
    #ifdef CONFIG_ISDN_AUDIO
    				isdn_audio_eval_dtmf(info);
    #endif
    				if ((tty = info->tty)) {
    					if (info->mcr & UART_MCR_RTS) {
    						c = TTY_FLIPBUF_SIZE - tty->flip.count;
    						if (c > 0) {
    							save_flags(flags);
    							cli();
    							r = isdn_readbchan(info->isdn_driver, info->isdn_channel,
    									   tty->flip.char_buf_ptr,
    									   tty->flip.flag_buf_ptr, c, 0);
    							/* CISCO AsyncPPP Hack */
    							if (!(info->emu.mdmreg[REG_CPPP] & BIT_CPPP))
    								memset(tty->flip.flag_buf_ptr, 0, r);
    							tty->flip.count += r;
    							tty->flip.flag_buf_ptr += r;
    							tty->flip.char_buf_ptr += r;
    							if (r)
    								queue_task(&tty->flip.tqueue, &tq_timer);
    							restore_flags(flags);
    						}
    					} else
    						r = 1;
    				} 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)
    		isdn_audio_calc_dtmf(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
    	if (skb_headroom(skb) < sizeof(isdn_audio_skb)) {
    		printk(KERN_WARNING
    		       "isdn_audio: insufficient skb_headroom, dropping\n");
    		kfree_skb(skb);
    		return 1;
    	}
    	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);
    	}
    #endif
    	/* Try to deliver directly via tty-flip-buf if queue is empty */
    	save_flags(flags);
    	cli();
    	if (skb_queue_empty(&dev->drv[di]->rpqueue[channel]))
    		if (isdn_tty_try_read(info, skb)) {
    			restore_flags(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
    			);
    	restore_flags(flags);
    	/* Schedule dequeuing */
    	if ((dev->modempoll) && (info->rcvsched))
    		isdn_timer_ctrl(ISDN_TIMER_MODEMREAD, 1);
    	return 1;
    }

    void
    isdn_tty_cleanup_xmit(modem_info * info)
    {
    	struct sk_buff *skb;
    	unsigned long flags;

    	save_flags(flags);
    	cli();
    	if (skb_queue_len(&info->xmit_queue))
    		while ((skb = skb_dequeue(&info->xmit_queue)))
    			kfree_skb(skb);
    #ifdef CONFIG_ISDN_AUDIO
    	if (skb_queue_len(&info->dtmf_queue))
    		while ((skb = skb_dequeue(&info->dtmf_queue)))
    			kfree_skb(skb);
    #endif
    	restore_flags(flags);
    }

    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->tty;
    		info->send_outstanding++;
    		info->msr &= ~UART_MSR_CTS;
    		info->lsr &= ~UART_LSR_TEMT;
    		if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
    		    tty->ldisc.write_wakeup)
    			(tty->ldisc.write_wakeup) (tty);
    		wake_up_interruptible(&tty->write_wait);
    		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->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, int from_user)
    {
    	char ch;

    	while (c--) {
    		if (from_user)
    			get_user(ch, buf);
    		else
    			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->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 flip-buffer.
     */
    static void
    isdn_tty_modem_do_ncarrier(unsigned long data)
    {
    	modem_info *info = (modem_info *) data;
    	isdn_tty_modem_result(3, 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;
    		info->nc_timer.function = isdn_tty_modem_do_ncarrier;
    		info->nc_timer.data = (unsigned long) info;
    		add_timer(&info->nc_timer);
    	}
    }

    /* 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];
    	isdn_ctrl cmd;
    	ulong flags;
    	int i;
    	int j;

    	for (j = 7; j >= 0; j--)
    		if (m->mdmreg[REG_SI1] & (1 << j)) {
    			si = bit2si[j];
    			break;
    		}
    #ifdef CONFIG_ISDN_AUDIO
    	if (si == 1) {
    		l2 = ISDN_PROTO_L2_TRANS;
    		usg = ISDN_USAGE_VOICE;
    	}
    #endif
    	m->mdmreg[REG_SI1I] = si2bit[si];
    	save_flags(flags);
    	cli();
    	i = isdn_get_free_channel(usg, l2, m->mdmreg[REG_L3PROT], -1, -1);
    	if (i < 0) {
    		restore_flags(flags);
    		isdn_tty_modem_result(6, 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();
    		restore_flags(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;
    		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;
    		strcpy(dev->num[i], n);
    		isdn_info_update();
    		isdn_command(&cmd);
    	}
    }

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

    	if (!info)
    		return;
    #ifdef ISDN_DEBUG_MODEM_HUP
    	printk(KERN_DEBUG "Mhup ttyI%d\n", info->line);
    #endif
    	info->rcvsched = 0;
    	isdn_tty_flush_buffer(info->tty);
    	if (info->online) {
    		info->last_lhup = local;
    		info->online = 0;
    		/* NO CARRIER message */
    		isdn_tty_modem_result(3, info);
    	}
    #ifdef CONFIG_ISDN_AUDIO
    	info->vonline = 0;
    	if (info->dtmf_state) {
    		kfree(info->dtmf_state);
    		info->dtmf_state = NULL;
    	}
    	if (info->adpcms) {
    		kfree(info->adpcms);
    		info->adpcms = NULL;
    	}
    	if (info->adpcmr) {
    		kfree(info->adpcmr);
    		info->adpcmr = NULL;
    	}
    #endif
    	if ((info->msr & UART_MSR_RI) &&
    		(info->emu.mdmreg[REG_RUNG] & BIT_RUNG))
    		isdn_tty_modem_result(12, info);
    	info->msr &= ~(UART_MSR_DCD | UART_MSR_RI);
    	info->lsr |= UART_LSR_TEMT;
    	if (info->isdn_driver >= 0) {
    		if (local) {
    			cmd.driver = info->isdn_driver;
    			cmd.command = ISDN_CMD_HANGUP;
    			cmd.arg = info->isdn_channel;
    			isdn_command(&cmd);
    		}
    		isdn_all_eaz(info->isdn_driver, info->isdn_channel);
    		info->emu.mdmreg[REG_RINGCNT] = 0;
    		usage = (info->emu.mdmreg[REG_SI1I] == 1) ?
    		    ISDN_USAGE_VOICE : ISDN_USAGE_MODEM;
    		isdn_free_channel(info->isdn_driver, info->isdn_channel,
    				  usage);
    	}
    	info->isdn_driver = -1;
    	info->isdn_channel = -1;
    	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 "avmb1/capicmd.h"  /* this should be moved in a common place */

    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) && l) {
    		cmd.parm.cmsg.Length = l+17;
    		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. unfortunatly 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);
    	if (!l) {
    		isdn_tty_modem_result(4, info);
    		return;
    	}
    	for (j = 7; j >= 0; j--)
    		if (m->mdmreg[REG_SI1] & (1 << j)) {
    			si = bit2si[j];
    			break;
    		}
    #ifdef CONFIG_ISDN_AUDIO
    	if (si == 1) {
    		l2 = ISDN_PROTO_L2_TRANS;
    		usg = ISDN_USAGE_VOICE;
    	}
    #endif
    	m->mdmreg[REG_SI1I] = si2bit[si];
    	save_flags(flags);
    	cli();
    	i = isdn_get_free_channel(usg, l2, m->mdmreg[REG_L3PROT], -1, -1);
    	if (i < 0) {
    		restore_flags(flags);
    		isdn_tty_modem_result(6, 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();
    		restore_flags(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+17;
    		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);
    	}
    }

    static inline int
    isdn_tty_paranoia_check(modem_info * info, kdev_t device, const char *routine)
    {
    #ifdef MODEM_PARANOIA_CHECK
    	if (!info) {
    		printk(KERN_WARNING "isdn_tty: null info_struct for (%d, %d) in %s\n",
    		       MAJOR(device), MINOR(device), routine);
    		return 1;
    	}
    	if (info->magic != ISDN_ASYNC_MAGIC) {
    		printk(KERN_WARNING "isdn_tty: bad magic for modem struct (%d, %d) in %s\n",
    		       MAJOR(device), MINOR(device), 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)
    {
    	uint cflag,
    	 cval,
    	 fcr,
    	 quot;
    	int i;

    	if (!info->tty || !info->tty->termios)
    		return;
    	cflag = info->tty->termios->c_cflag;

    	quot = i = cflag & CBAUD;
    	if (i & CBAUDEX) {
    		i &= ~CBAUDEX;
    		if (i < 1 || i > 2)
    			info->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;
    	fcr = 0;

    	/* CTS flow control flag and modem status interrupts */
    	if (cflag & CRTSCTS) {
    		info->flags |= ISDN_ASYNC_CTS_FLOW;
    	} else
    		info->flags &= ~ISDN_ASYNC_CTS_FLOW;
    	if (cflag & CLOCAL)
    		info->flags &= ~ISDN_ASYNC_CHECK_CD;
    	else {
    		info->flags |= ISDN_ASYNC_CHECK_CD;
    	}
    }

    static int
    isdn_tty_startup(modem_info * info)
    {
    	ulong flags;

    	if (info->flags & ISDN_ASYNC_INITIALIZED)
    		return 0;
    	save_flags(flags);
    	cli();
    	isdn_MOD_INC_USE_COUNT();
    #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->tty)
    		clear_bit(TTY_IO_ERROR, &info->tty->flags);
    	/*
    	 * and set the speed of the serial port
    	 */
    	isdn_tty_change_speed(info);

    	info->flags |= ISDN_ASYNC_INITIALIZED;
    	info->msr |= (UART_MSR_DSR | UART_MSR_CTS);
    	info->send_outstanding = 0;
    	restore_flags(flags);
    	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)
    {
    	ulong flags;

    	if (!(info->flags & ISDN_ASYNC_INITIALIZED))
    		return;
    #ifdef ISDN_DEBUG_MODEM_OPEN
    	printk(KERN_DEBUG "Shutting down isdnmodem port %d ....\n", info->line);
    #endif
    	save_flags(flags);
    	cli();                  /* Disable interrupts */
    	isdn_MOD_DEC_USE_COUNT();
    	info->msr &= ~UART_MSR_RI;
    	if (!info->tty || (info->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->tty)
    		set_bit(TTY_IO_ERROR, &info->tty->flags);

    	info->flags &= ~ISDN_ASYNC_INITIALIZED;
    	restore_flags(flags);
    }

    /* 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, int from_user, const u_char * buf, int count)
    {
    	int c;
    	int total = 0;
    	modem_info *info = (modem_info *) tty->driver_data;

    	if (isdn_tty_paranoia_check(info, tty->device, "isdn_tty_write"))
    		return 0;
    	if (!tty)
    		return 0;
    	if (from_user)
    		down(&info->write_sem);
    	/* See isdn_tty_senddown() */
    	atomic_inc(&info->xmit_lock);
    	while (1) {
    		c = MIN(count, info->xmit_size - info->xmit_count);
    		if (info->isdn_driver >= 0)
    			c = MIN(c, dev->drv[info->isdn_driver]->maxbufsize);
    		if (c <= 0)
    			break;
    		if ((info->online > 1)
    #ifdef CONFIG_ISDN_AUDIO
    		    || (info->vonline & 3)
    #endif
    			) {
    			atemu *m = &info->emu;

    #ifdef CONFIG_ISDN_AUDIO
    			if (!info->vonline)
    #endif
    				isdn_tty_check_esc(buf, m->mdmreg[REG_ESC], c,
    						   &(m->pluscount),
    						   &(m->lastplus),
    						   from_user);
    			if (from_user)
    				copy_from_user(&(info->xmit_buf[info->xmit_count]), buf, c);
    			else
    				memcpy(&(info->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.
    						 */
    						if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
    						 tty->ldisc.write_wakeup)
    							(tty->ldisc.write_wakeup) (tty);
    						wake_up_interruptible(&tty->write_wait);
    						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, from_user)) {
    						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
    #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(3, info);
    				isdn_tty_modem_hup(info, 1);
    			} else
    				c = isdn_tty_edit_at(buf, c, info, from_user);
    		}
    		buf += c;
    		count -= c;
    		total += c;
    	}
    	if ((info->xmit_count) || (skb_queue_len(&info->xmit_queue)))
    		isdn_timer_ctrl(ISDN_TIMER_MODEMXMIT, 1);
    	atomic_dec(&info->xmit_lock);
    	if (from_user)
    		up(&info->write_sem);
    	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->device, "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->device, "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;
    	unsigned long flags;

    	save_flags(flags);
    	cli();
    	if (!tty) {
    		restore_flags(flags);
    		return;
    	}
    	info = (modem_info *) tty->driver_data;
    	if (isdn_tty_paranoia_check(info, tty->device, "isdn_tty_flush_buffer")) {
    		restore_flags(flags);
    		return;
    	}
    	isdn_tty_cleanup_xmit(info);
    	info->xmit_count = 0;
    	restore_flags(flags);
    	wake_up_interruptible(&tty->write_wait);
    	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
    	    tty->ldisc.write_wakeup)
    		(tty->ldisc.write_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->device, "isdn_tty_flush_chars"))
    		return;
    	if ((info->xmit_count) || (skb_queue_len(&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->device, "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->device, "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 * value)
    {
    	u_char status;
    	uint result;
    	ulong flags;

    	save_flags(flags);
    	cli();
    	status = info->lsr;
    	restore_flags(flags);
    	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
    	put_user(result, (uint *) value);
    	return 0;
    }

    static int
    isdn_tty_get_modem_info(modem_info * info, uint * value)
    {
    	u_char control,
    	 status;
    	uint result;
    	ulong flags;

    	control = info->mcr;
    	save_flags(flags);
    	cli();
    	status = info->msr;
    	restore_flags(flags);
    	result = ((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);
    	put_user(result, (uint *) value);
    	return 0;
    }

    static int
    isdn_tty_set_modem_info(modem_info * info, uint cmd, uint * value)
    {
    	uint arg;
    	int pre_dtr;

    	get_user(arg, (uint *) value);
    	switch (cmd) {
    		case TIOCMBIS:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCMBIS\n", info->line);
    #endif
    			if (arg & TIOCM_RTS) {
    				info->mcr |= UART_MCR_RTS;
    			}
    			if (arg & TIOCM_DTR) {
    				info->mcr |= UART_MCR_DTR;
    				isdn_tty_modem_ncarrier(info);
    			}
    			break;
    		case TIOCMBIC:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCMBIC\n", info->line);
    #endif
    			if (arg & TIOCM_RTS) {
    				info->mcr &= ~UART_MCR_RTS;
    			}
    			if (arg & 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 TIOCMBIC\n");
    #endif
    					if (info->online)
    						info->ncarrier = 1;
    					isdn_tty_modem_hup(info, 1);
    				}
    			}
    			break;
    		case TIOCMSET:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCMSET\n", info->line);
    #endif
    			pre_dtr = (info->mcr & UART_MCR_DTR);
    			info->mcr = ((info->mcr & ~(UART_MCR_RTS | UART_MCR_DTR))
    				 | ((arg & TIOCM_RTS) ? UART_MCR_RTS : 0)
    			       | ((arg & TIOCM_DTR) ? UART_MCR_DTR : 0));
    			if (pre_dtr |= (info->mcr & UART_MCR_DTR)) {
    				if (!(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);
    					}
    				} else
    					isdn_tty_modem_ncarrier(info);
    			}
    			break;
    		default:
    			return -EINVAL;
    	}
    	return 0;
    }

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

    	if (isdn_tty_paranoia_check(info, tty->device, "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 TIOCGSOFTCAR:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCGSOFTCAR\n", info->line);
    #endif
    			error = verify_area(VERIFY_WRITE, (void *) arg, sizeof(long));
    			if (error)
    				return error;
    			put_user(C_CLOCAL(tty) ? 1 : 0, (ulong *) arg);
    			return 0;
    		case TIOCSSOFTCAR:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCSSOFTCAR\n", info->line);
    #endif
    			error = verify_area(VERIFY_READ, (void *) arg, sizeof(long));
    			if (error)
    				return error;
    			get_user(arg, (ulong *) arg);
    			tty->termios->c_cflag =
    			    ((tty->termios->c_cflag & ~CLOCAL) |
    			     (arg ? CLOCAL : 0));
    			return 0;
    		case TIOCMGET:
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCMGET\n", info->line);
    #endif
    			error = verify_area(VERIFY_WRITE, (void *) arg, sizeof(uint));
    			if (error)
    				return error;
    			return isdn_tty_get_modem_info(info, (uint *) arg);
    		case TIOCMBIS:
    		case TIOCMBIC:
    		case TIOCMSET:
    			error = verify_area(VERIFY_READ, (void *) arg, sizeof(uint));
    			if (error)
    				return error;
    			return isdn_tty_set_modem_info(info, cmd, (uint *) arg);
    		case TIOCSERGETLSR:	/* Get line status register */
    #ifdef ISDN_DEBUG_MODEM_IOCTL
    			printk(KERN_DEBUG "ttyI%d ioctl TIOCSERGETLSR\n", info->line);
    #endif
    			error = verify_area(VERIFY_WRITE, (void *) arg, sizeof(uint));
    			if (error)
    				return error;
    			else
    				return isdn_tty_get_lsr_info(info, (uint *) 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 termios *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)
    			return;
    		isdn_tty_change_speed(info);
    		if ((old_termios->c_cflag & CRTSCTS) &&
    		    !(tty->termios->c_cflag & CRTSCTS)) {
    			tty->hw_stopped = 0;
    		}
    	}
    }

    /*
     * ------------------------------------------------------------
     * isdn_tty_open() and friends
     * ------------------------------------------------------------
     */
    static int
    isdn_tty_block_til_ready(struct tty_struct *tty, struct file *filp, modem_info * info)
    {
    	struct wait_queue wait =
    	{current, NULL};
    	int do_clocal = 0;
    	unsigned long flags;
    	int retval;

    	/*
    	 * If the device is in the middle of being closed, then block
    	 * until it's done, and then try again.
    	 */
    	if (tty_hung_up_p(filp) ||
    	    (info->flags & ISDN_ASYNC_CLOSING)) {
    		if (info->flags & ISDN_ASYNC_CLOSING)
    			interruptible_sleep_on(&info->close_wait);
    #ifdef MODEM_DO_RESTART
    		if (info->flags & ISDN_ASYNC_HUP_NOTIFY)
    			return -EAGAIN;
    		else
    			return -ERESTARTSYS;
    #else
    		return -EAGAIN;
    #endif
    	}
    	/*
    	 * If this is a callout device, then just make sure the normal
    	 * device isn't being used.
    	 */
    	if (tty->driver.subtype == ISDN_SERIAL_TYPE_CALLOUT) {
    		if (info->flags & ISDN_ASYNC_NORMAL_ACTIVE)
    			return -EBUSY;
    		if ((info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) &&
    		    (info->flags & ISDN_ASYNC_SESSION_LOCKOUT) &&
    		    (info->session != current->session))
    			return -EBUSY;
    		if ((info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) &&
    		    (info->flags & ISDN_ASYNC_PGRP_LOCKOUT) &&
    		    (info->pgrp != current->pgrp))
    			return -EBUSY;
    		info->flags |= ISDN_ASYNC_CALLOUT_ACTIVE;
    		return 0;
    	}
    	/*
    	 * If non-blocking mode is set, then make the check up front
    	 * and then exit.
    	 */
    	if ((filp->f_flags & O_NONBLOCK) ||
    	    (tty->flags & (1 << TTY_IO_ERROR))) {
    		if (info->flags & ISDN_ASYNC_CALLOUT_ACTIVE)
    			return -EBUSY;
    		info->flags |= ISDN_ASYNC_NORMAL_ACTIVE;
    		return 0;
    	}
    	if (info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) {
    		if (info->normal_termios.c_cflag & CLOCAL)
    			do_clocal = 1;
    	} else {
    		if (tty->termios->c_cflag & CLOCAL)
    			do_clocal = 1;
    	}
    	/*
    	 * Block waiting for the carrier detect and the line to become
    	 * free (i.e., not in use by the callout).  While we are in
    	 * this loop, info->count is dropped by one, so that
    	 * isdn_tty_close() knows when to free things.  We restore it upon
    	 * exit, either normal or abnormal.
    	 */
    	retval = 0;
    	add_wait_queue(&info->open_wait, &wait);
    #ifdef ISDN_DEBUG_MODEM_OPEN
    	printk(KERN_DEBUG "isdn_tty_block_til_ready before block: ttyi%d, count = %d\n",
    	       info->line, info->count);
    #endif
    	save_flags(flags);
    	cli();
    	if (!(tty_hung_up_p(filp)))
    		info->count--;
    	restore_flags(flags);
    	info->blocked_open++;
    	while (1) {
    		current->state = TASK_INTERRUPTIBLE;
    		if (tty_hung_up_p(filp) ||
    		    !(info->flags & ISDN_ASYNC_INITIALIZED)) {
    #ifdef MODEM_DO_RESTART
    			if (info->flags & ISDN_ASYNC_HUP_NOTIFY)
    				retval = -EAGAIN;
    			else
    				retval = -ERESTARTSYS;
    #else
    			retval = -EAGAIN;
    #endif
    			break;
    		}
    		if (!(info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) &&
    		    !(info->flags & ISDN_ASYNC_CLOSING) &&
    		    (do_clocal || (info->msr & UART_MSR_DCD))) {
    			break;
    		}
    		if (signal_pending(current)) {
    			retval = -ERESTARTSYS;
    			break;
    		}
    #ifdef ISDN_DEBUG_MODEM_OPEN
    		printk(KERN_DEBUG "isdn_tty_block_til_ready blocking: ttyi%d, count = %d\n",
    		       info->line, info->count);
    #endif
    		schedule();
    	}
    	current->state = TASK_RUNNING;
    	remove_wait_queue(&info->open_wait, &wait);
    	if (!tty_hung_up_p(filp))
    		info->count++;
    	info->blocked_open--;
    #ifdef ISDN_DEBUG_MODEM_OPEN
    	printk(KERN_DEBUG "isdn_tty_block_til_ready after blocking: ttyi%d, count = %d\n",
    	       info->line, info->count);
    #endif
    	if (retval)
    		return retval;
    	info->flags |= ISDN_ASYNC_NORMAL_ACTIVE;
    	return 0;
    }

    /*
     * 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;
    	int retval,
    	 line;

    	line = MINOR(tty->device) - tty->driver.minor_start;
    	if (line < 0 || line > ISDN_MAX_CHANNELS)
    		return -ENODEV;
    	info = &dev->mdm.info[line];
    	if (isdn_tty_paranoia_check(info, tty->device, "isdn_tty_open"))
    		return -ENODEV;
    #ifdef ISDN_DEBUG_MODEM_OPEN
    	printk(KERN_DEBUG "isdn_tty_open %s%d, count = %d\n", tty->driver.name,
    	       info->line, info->count);
    #endif
    	info->count++;
    	tty->driver_data = info;
    	info->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 = isdn_tty_block_til_ready(tty, filp, info);
    	if (retval) {
    #ifdef ISDN_DEBUG_MODEM_OPEN
    		printk(KERN_DEBUG "isdn_tty_open return after isdn_tty_block_til_ready \n");
    #endif
    		return retval;
    	}
    	if ((info->count == 1) && (info->flags & ISDN_ASYNC_SPLIT_TERMIOS)) {
    		if (tty->driver.subtype == ISDN_SERIAL_TYPE_NORMAL)
    			*tty->termios = info->normal_termios;
    		else
    			*tty->termios = info->callout_termios;
    		isdn_tty_change_speed(info);
    	}
    	info->session = current->session;
    	info->pgrp = current->pgrp;
    #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;
    	ulong flags;
    	ulong timeout;

    	if (!info || isdn_tty_paranoia_check(info, tty->device, "isdn_tty_close"))
    		return;
    	save_flags(flags);
    	cli();
    	if (tty_hung_up_p(filp)) {
    		restore_flags(flags);
    #ifdef ISDN_DEBUG_MODEM_OPEN
    		printk(KERN_DEBUG "isdn_tty_close return after tty_hung_up_p\n");
    #endif
    		return;
    	}
    	if ((tty->count == 1) && (info->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", info->count);
    		info->count = 1;
    	}
    	if (--info->count < 0) {
    		printk(KERN_ERR "isdn_tty_close: bad port count for ttyi%d: %d\n",
    		       info->line, info->count);
    		info->count = 0;
    	}
    	if (info->count) {
    		restore_flags(flags);
    #ifdef ISDN_DEBUG_MODEM_OPEN
    		printk(KERN_DEBUG "isdn_tty_close after info->count != 0\n");
    #endif
    		return;
    	}
    	info->flags |= ISDN_ASYNC_CLOSING;
    	/*
    	 * Save the termios structure, since this port may have
    	 * separate termios for callout and dialin.
    	 */
    	if (info->flags & ISDN_ASYNC_NORMAL_ACTIVE)
    		info->normal_termios = *tty->termios;
    	if (info->flags & ISDN_ASYNC_CALLOUT_ACTIVE)
    		info->callout_termios = *tty->termios;

    	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 (info->flags & ISDN_ASYNC_INITIALIZED) {
    		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)) {
    			current->state = TASK_INTERRUPTIBLE;
    			current->timeout = jiffies + 20;
    			schedule();
    			if (jiffies > timeout)
    				break;
    		}
    	}
    	dev->modempoll--;
    	isdn_tty_shutdown(info);
    	if (tty->driver.flush_buffer)
    		tty->driver.flush_buffer(tty);
    	if (tty->ldisc.flush_buffer)
    		tty->ldisc.flush_buffer(tty);
    	info->tty = 0;
    	info->ncarrier = 0;
    	tty->closing = 0;
    	if (info->blocked_open) {
    		current->state = TASK_INTERRUPTIBLE;
    		current->timeout = jiffies + 50;
    		schedule();
    		wake_up_interruptible(&info->open_wait);
    	}
    	info->flags &= ~(ISDN_ASYNC_NORMAL_ACTIVE | ISDN_ASYNC_CALLOUT_ACTIVE |
    			 ISDN_ASYNC_CLOSING);
    	wake_up_interruptible(&info->close_wait);
    	restore_flags(flags);
    #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;

    	if (isdn_tty_paranoia_check(info, tty->device, "isdn_tty_hangup"))
    		return;
    	isdn_tty_shutdown(info);
    	info->count = 0;
    	info->flags &= ~(ISDN_ASYNC_NORMAL_ACTIVE | ISDN_ASYNC_CALLOUT_ACTIVE);
    	info->tty = 0;
    	wake_up_interruptible(&info->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->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   ) */
    }
    #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_ANZREG);
    		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
    	m->mdmcmdl = 0;
    }

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

    int
    isdn_tty_modem_init(void)
    {
    	modem *m;
    	int i;
    	modem_info *info;

    	m = &dev->mdm;
    	memset(&m->tty_modem, 0, sizeof(struct tty_driver));
    	m->tty_modem.magic = TTY_DRIVER_MAGIC;
    	m->tty_modem.name = isdn_ttyname_ttyI;
    	m->tty_modem.major = ISDN_TTY_MAJOR;
    	m->tty_modem.minor_start = 0;
    	m->tty_modem.num = ISDN_MAX_CHANNELS;
    	m->tty_modem.type = TTY_DRIVER_TYPE_SERIAL;
    	m->tty_modem.subtype = ISDN_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.refcount = &m->refcount;
    	m->tty_modem.table = m->modem_table;
    	m->tty_modem.termios = m->modem_termios;
    	m->tty_modem.termios_locked = m->modem_termios_locked;
    	m->tty_modem.open = isdn_tty_open;
    	m->tty_modem.close = isdn_tty_close;
    	m->tty_modem.write = isdn_tty_write;
    	m->tty_modem.put_char = NULL;
    	m->tty_modem.flush_chars = isdn_tty_flush_chars;
    	m->tty_modem.write_room = isdn_tty_write_room;
    	m->tty_modem.chars_in_buffer = isdn_tty_chars_in_buffer;
    	m->tty_modem.flush_buffer = isdn_tty_flush_buffer;
    	m->tty_modem.ioctl = isdn_tty_ioctl;
    	m->tty_modem.throttle = isdn_tty_throttle;
    	m->tty_modem.unthrottle = isdn_tty_unthrottle;
    	m->tty_modem.set_termios = isdn_tty_set_termios;
    	m->tty_modem.stop = NULL;
    	m->tty_modem.start = NULL;
    	m->tty_modem.hangup = isdn_tty_hangup;
    	m->tty_modem.driver_name = "isdn_tty";
    	/*
    	 * The callout device is just like normal device except for
    	 * major number and the subtype code.
    	 */
    	m->cua_modem = m->tty_modem;
    	m->cua_modem.name = isdn_ttyname_cui;
    	m->cua_modem.major = ISDN_TTYAUX_MAJOR;
    	m->tty_modem.minor_start = 0;
    	m->cua_modem.subtype = ISDN_SERIAL_TYPE_CALLOUT;

    	if (tty_register_driver(&m->tty_modem)) {
    		printk(KERN_WARNING "isdn_tty: Couldn't register modem-device\n");
    		return -1;
    	}
    	if (tty_register_driver(&m->cua_modem)) {
    		printk(KERN_WARNING "isdn_tty: Couldn't register modem-callout-device\n");
    		return -2;
    	}
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		info = &m->info[i];
    		info->write_sem = MUTEX;
    		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->tty = 0;
    		info->x_char = 0;
    		info->count = 0;
    		info->blocked_open = 0;
    		info->callout_termios = m->cua_modem.init_termios;
    		info->normal_termios = m->tty_modem.init_termios;
    		info->open_wait = 0;
    		info->close_wait = 0;
    		info->isdn_driver = -1;
    		info->isdn_channel = -1;
    		info->drv_index = -1;
    		info->xmit_size = ISDN_SERIAL_XMIT_SIZE;
    		skb_queue_head_init(&info->xmit_queue);
    #ifdef CONFIG_ISDN_AUDIO
    		skb_queue_head_init(&info->dtmf_queue);
    #endif
    		if (!(info->xmit_buf = kmalloc(ISDN_SERIAL_XMIT_MAX + 5, GFP_KERNEL))) {
    			printk(KERN_ERR "Could not allocate modem xmit-buffer\n");
    			return -3;
    		}
    		/* Make room for T.70 header */
    		info->xmit_buf += 4;
    	}
    	return 0;
    }

    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_wildmat(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
    		return isdn_wildmat(cid, isdn_map_eaz2msn(emu->msn, di));
    }

    /*
     * 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[32];
    	ulong flags;

    	if (!setup.phone[0]) {
    		nr[0] = '0';
    		nr[1] = '\0';
    		printk(KERN_INFO "isdn_tty: Incoming call without OAD, assuming '0'\n");
    	} else
    		strcpy(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;
    	save_flags(flags);
    	cli();
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		modem_info *info = &dev->mdm.info[i];

    		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\n");
    			printk(KERN_DEBUG "m_fi: idx=%d flags=%08lx drv=%d ch=%d usg=%d\n", idx,
    			       info->flags, info->isdn_driver, info->isdn_channel,
    			       dev->usage[idx]);
    #endif
    			if (
    #ifndef FIX_FILE_TRANSFER
    				(info->flags & ISDN_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] |= (si1 == 1) ? ISDN_USAGE_VOICE : ISDN_USAGE_MODEM;
    					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();
    					restore_flags(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(2, info);
    					isdn_timer_ctrl(ISDN_TIMER_MODEMRING, 1);
    					return 1;
    				}
    			}
    		}
    	}
    	restore_flags(flags);
    	printk(KERN_INFO "isdn_tty: call from %s -> %s %s\n", nr, eaz,
    	       (dev->drv[di]->reject_bus && (wret != 2))? "rejected" : "ignored");
    	return (wret == 2)?3:0;
    }

    #define TTY_IS_ACTIVE(info) \
    	(info->flags & (ISDN_ASYNC_NORMAL_ACTIVE | ISDN_ASYNC_CALLOUT_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_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) {
    						info->dialing = 0;
    						isdn_tty_modem_result(7, info);
    					}
    #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
    				/* Schedule CONNECT-Message to any tty
    				 * waiting for it and
    				 * set DCD-bit of its modem-status.
    				 */
    				if (TTY_IS_ACTIVE(info)) {
    					info->msr |= UART_MSR_DCD;
    					info->emu.charge = 0;
    					if (info->dialing) {
    						info->dialing = 0;
    						info->last_dir = 1;
    					} else
    						info->last_dir = 0;
    					info->rcvsched = 1;
    					if (USG_MODEM(dev->usage[i]))
    						isdn_tty_modem_result(5, info);
    					if (USG_VOICE(dev->usage[i]))
    						isdn_tty_modem_result(11, 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(6, 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;
    		}
    	}
    	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.
     */
    static void
    isdn_tty_at_cout(char *msg, modem_info * info)
    {
    	struct tty_struct *tty;
    	atemu *m = &info->emu;
    	char *p;
    	char c;
    	ulong flags;

    	if (!msg) {
    		printk(KERN_WARNING "isdn_tty: Null-Message in isdn_tty_at_cout\n");
    		return;
    	}
    	save_flags(flags);
    	cli();
    	tty = info->tty;
    	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 ((info->flags & ISDN_ASYNC_CLOSING) || (!tty)) {
    			restore_flags(flags);
    			return;
    		}
    		if (tty->flip.count >= TTY_FLIPBUF_SIZE)
    			break;
    		tty_insert_flip_char(tty, c, 0);
    	}
    	restore_flags(flags);
    	queue_task(&tty->flip.tqueue, &tq_timer);
    }

    /*
     * 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,
    		   int *lastplus, int from_user)
    {
    	char cbuf[3];

    	if (plus > 127)
    		return;
    	if (count > 3) {
    		p += count - 3;
    		count = 3;
    		*pluscount = 0;
    	}
    	if (from_user) {
    		copy_from_user(cbuf, p, count);
    		p = cbuf;
    	}
    	while (count > 0) {
    		if (*(p++) == plus) {
    			if ((*pluscount)++) {
    				/* Time since last '+' > 0.5 sec. ? */
    				if ((jiffies - *lastplus) > PLUSWAIT1)
    					*pluscount = 1;
    			} else {
    				/* Time since last non-'+' < 1.5 sec. ? */
    				if ((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"};
    	ulong flags;
    	char s[ISDN_MSNLEN+10];

    	switch (code) {
    		case 2:
    			m->mdmreg[REG_RINGCNT]++;	/* RING */
    			if (m->mdmreg[REG_RINGCNT] == m->mdmreg[REG_RINGATA])
    				/* Automatically accept incoming call */
    				isdn_tty_cmd_ATA(info);
    			break;
    		case 3:
    			/* NO CARRIER */
    #ifdef ISDN_DEBUG_MODEM_HUP
    			printk(KERN_DEBUG "modem_result: NO CARRIER %d %d\n",
    			       (info->flags & ISDN_ASYNC_CLOSING),
    			       (!info->tty));
    #endif
    			save_flags(flags);
    			cli();
    			m->mdmreg[REG_RINGCNT] = 0;
    			del_timer(&info->nc_timer);
    			info->ncarrier = 0;
    			if ((info->flags & ISDN_ASYNC_CLOSING) || (!info->tty)) {
    				restore_flags(flags);
    				return;
    			}
    			restore_flags(flags);
    #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 1:
    		case 5:
    			sprintf(info->last_cause, "0000");
    			if (!info->online)
    				info->online = 2;
    			break;
    		case 11:
    #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;
    	}
    	if (m->mdmreg[REG_RESP] & BIT_RESP) {
    		/* Show results */
    		isdn_tty_at_cout("\r\n", info);
    		if (m->mdmreg[REG_RESPNUM] & BIT_RESPNUM) {
    			/* Show numeric results */
    			sprintf(s, "%d", code);
    			isdn_tty_at_cout(s, info);
    		} else {
    			if ((code == 2) &&
    				(m->mdmreg[REG_RUNG] & BIT_RUNG) &&
    				(m->mdmreg[REG_RINGCNT] > 1))
    				return;
    			if ((code == 2) && (!(m->mdmreg[REG_CIDONCE] & BIT_CIDONCE))) {
    				isdn_tty_at_cout("CALLER NUMBER: ", info);
    				isdn_tty_at_cout(dev->num[info->drv_index], info);
    				isdn_tty_at_cout("\r\n", info);
    			}
    			isdn_tty_at_cout(msg[code], info);
    			switch (code) {
    				case 2:
    					/* Append CPN, if enabled */
    					if ((m->mdmreg[REG_RESRXT] & BIT_RESRXT)) {
    						sprintf(s, "/%s", m->cpn);
    						isdn_tty_at_cout(s, info);
    					}
    					/* Print CID only once, _after_ 1.st 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);
    					}
    					break;
    				case 3:
    				case 6:
    				case 7:
    				case 8:
    					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 5:
    					/* 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 == 3) {
    		save_flags(flags);
    		cli();
    		if ((info->flags & ISDN_ASYNC_CLOSING) || (!info->tty)) {
    			restore_flags(flags);
    			return;
    		}
    		if (info->tty->ldisc.flush_buffer)
    			info->tty->ldisc.flush_buffer(info->tty);
    		if ((info->flags & ISDN_ASYNC_CHECK_CD) &&
    		    (!((info->flags & ISDN_ASYNC_CALLOUT_ACTIVE) &&
    		       (info->flags & ISDN_ASYNC_CALLOUT_NOHUP)))) {
    			tty_hangup(info->tty);
    		}
    		restore_flags(flags);
    	}
    }

    /*
     * 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)
    {
    	while ((*p[0] >= '0' && *p[0] <= '9') ||
    	       /* Why a comma ??? */
    	       (*p[0] == ','))
    		*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=39;	/* MUST match the size in isdn_tty_parse to avoid
    				buffer overflow */

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

    #define PARSE_ERROR { isdn_tty_modem_result(4, info); return; }
    #define PARSE_ERROR1 { isdn_tty_modem_result(4, 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;
    		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 'D':
    			/* &D - Set DCD-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]++;
    			isdn_tty_reset_profile(m);
    			isdn_tty_modem_reset_regs(info, 1);
    			break;
    		case 'L':
    			/* &L -Set Numbers to listen on */
    			p[0]++;
    			i = 0;
    			while ((strchr("0123456789,*[]?;", *p[0])) &&
    			       (i < ISDN_LMSNLEN))
    				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_ANZREG; 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_ANZREG)
    		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)
    				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);
    		isdn_command(&cmd);
    		cmd.driver = info->isdn_driver;
    		cmd.arg = info->isdn_channel;
    		cmd.command = ISDN_CMD_ACCEPTD;
    		isdn_command(&cmd);
    	} else
    		isdn_tty_modem_result(8, info);
    }

    #ifdef CONFIG_ISDN_AUDIO
    /*
     * Parse AT+F.. commands
     */
    static int
    isdn_tty_cmd_PLUSF(char **p, modem_info * info)
    {
    	atemu *m = &info->emu;
    	int par;
    	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);
    				isdn_tty_at_cout(rs, info);
    				break;
    			case '=':
    				p[0]++;
    				switch (*p[0]) {
    					case '0':
    						p[0]++;
    						m->mdmreg[REG_SI1] = 4;
    						info->xmit_size =
    						    m->mdmreg[REG_PSIZE] * 16;
    						break;
    					case '2':
    						printk(KERN_DEBUG "isdn_tty: FCLASS=2\n");
    						p[0]++;
    						break;
    					case '8':
    						p[0]++;
    						m->mdmreg[REG_SI1] = 5;
    						info->xmit_size = VBUF;
    						break;
    					case '?':
    						p[0]++;
    						isdn_tty_at_cout("\r\n0,2,8",
    								 info);
    						break;
    					default:
    						PARSE_ERROR1;
    				}
    				break;
    			default:
    				PARSE_ERROR1;
    		}
    		return 0;
    	}
    	if (!strncmp(p[0], "AA", 2)) {
    		p[0] += 2;
    		switch (*p[0]) {
    			case '?':
    				p[0]++;
    				sprintf(rs, "\r\n%d",
    					m->mdmreg[REG_RINGATA]);
    				isdn_tty_at_cout(rs, info);
    				break;
    			case '=':
    				p[0]++;
    				par = isdn_getnum(p);
    				if ((par < 0) || (par > 255))
    					PARSE_ERROR1;
    				m->mdmreg[REG_RINGATA] = par;
    				break;
    			default:
    				PARSE_ERROR1;
    		}
    		return 0;
    	}
            if (!strncmp(p[0], "TBC=", 4)) { /* UNKLAR !! */
                    p[0] += 4;
                    printk(KERN_DEBUG "isdn_tty: Fax FTBC=%c\n", *p[0]);
                    switch (*p[0]) {
                            case '0':
                                    p[0]++;
                                    break;
                            default:
                                    PARSE_ERROR1;
                    }
                    return 0;
            }
            if (!strncmp(p[0], "BOR=", 4)) { /* UNKLAR !! */
                    p[0] += 4;
                    printk(KERN_DEBUG "isdn_tty: Fax FBOR=%c\n", *p[0]);
                    switch (*p[0]) {
                            case '0':
                                    p[0]++;
                                    break;
                            default:
                                    PARSE_ERROR1;
                    }
                    return 0;
            }
            if (!strncmp(p[0], "DCC=", 4)) { /* SETUP irgendwie !! */
    		int i, val[]={0,0,0,0,0,0,0,0};

                    p[0] += 4;
                    if (*p[0] == '?') {
    			isdn_tty_at_cout("\r\n(0,1),(0-5),(0-2),(0-2),(0,1),(0),(0),(0-7)",info);
    			p[0]++;
                    } else {
    			for (i=0; (*p[0]>='0') && (*p[0]<='9'); i++) {
    				val[i] = *p[0] - 48;
    				p[0]++;
    				if (*p[0] == ',')
    					p[0]++;
    			}
    			printk(KERN_DEBUG "isdn_tty: Fax Setup values=%d,%d,%d,%d,%d,%d,%d,%d\n",
    			       val[0], val[1], val[2], val[3], val[4], val[5], val[6], val[7]);
                    }
                    return 0;
            }
            if (!strncmp(p[0], "LID=", 4)) { /* set sender ID !! */
    		char senderID[80];
    		int i;

                    p[0] += 4;
                    if (*p[0] =='"')
    			p[0]++;
                    for(i=0; (*p[0]) && (*p[0] != '"'); i++)
    			senderID[i] = *p[0]++;
                    senderID[i] = 0;
                    if (*p[0] =='"')
    			p[0]++;
                    printk(KERN_DEBUG "isdn_tty: Fax sender=>%s<\n", senderID);
                    return 0;
            }
            if (!strncmp(p[0], "MFR?", 4)) {
                    p[0] += 4;
                    printk(KERN_DEBUG "isdn_tty: FMFR?\n");
                    isdn_tty_at_cout("\r\nISDNfax", info);
                    return 0;
            }
            if (!strncmp(p[0], "MDL?", 4)) {
                    p[0] += 4;
                    printk(KERN_DEBUG "isdn_tty: FMDL?\n");
                    isdn_tty_at_cout("\r\nAVM-B1", info);
                    return 0;
            }
            if (!strncmp(p[0], "AP=?", 4)) {
                    p[0] += 4;
                    printk(KERN_DEBUG "isdn_tty: FAP=?\n");
                    return 0;
            }
            if (!strncmp(p[0], "PHCTO=", 6)) {
    		/* beim trace mit dem zyxel folgt der wert 30 ;*/
                    p[0] += 6;
                    printk(KERN_DEBUG "isdn_tty: FPHCTO=%s\n", p[0]);
                    return 0;
            }
            if (!strncmp(p[0], "CR=", 3)) {
                    p[0] += 3;
                    printk(KERN_DEBUG "isdn_tty: FCR=%s\n", p[0]);
                    return 0;
            }
            printk(KERN_DEBUG "isdn_tty: unknown token=>AT+F%s<\n", p[0]);
    	PARSE_ERROR1;
    }

    /*
     * Parse AT+V.. commands
     */
    static int
    isdn_tty_cmd_PLUSV(char **p, modem_info * info)
    {
    	atemu *m = &info->emu;
    	static char *vcmd[] =
    	{"NH", "IP", "LS", "RX", "SD", "SM", "TX", 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(8, 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->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(1, 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]++;
    					switch (*p[0]) {
    						case '0':
    						case '1':
    						case '2':
    						case '3':
    							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;
    						case '?':
    							p[0]++;
    							isdn_tty_at_cout("\r\n<0-31>,<0-255>",
    								   info);
    							break;
    						default:
    							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)",
    								   info);
    							isdn_tty_at_cout("6;ULAW;8;0;(8000)",
    								   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(8, 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(1, info);
    			return 0;
    			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[40];

    #ifdef ISDN_DEBUG_AT
    	printk(KERN_DEBUG "AT: '%s'\n", m->mdmcmd);
    #endif
    	for (p = &m->mdmcmd[2]; *p;) {
    		switch (*p) {
    			case 'A':
    				/* A - Accept incoming call */
    				p++;
    				isdn_tty_cmd_ATA(info);
    				return;
    				break;
    			case 'D':
    				/* D - Dial */
    				isdn_tty_getdial(++p, ds, sizeof ds);
    				p += strlen(p);
    				if (!strlen(m->msn))
    					isdn_tty_modem_result(10, 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++;
                                                    sprintf(ds, "\r\n%d", info->emu.charge);
                                                    isdn_tty_at_cout(ds, info);
                                                    break;
    					default:
    				}
    				break;
    			case 'O':
    				/* O - Go online */
    				p++;
    				if (info->msr & UART_MSR_DCD)
    					/* if B-Channel is up */
    					isdn_tty_modem_result(5, info);
    				else
    					isdn_tty_modem_result(3, 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++;
    				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))
    							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 */
    						isdn_tty_get_msnstr(ds, &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(0, 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)
     *   user     flag: buffer is in userspace
     */
    static int
    isdn_tty_edit_at(const char *p, int count, modem_info * info, int user)
    {
    	atemu *m = &info->emu;
    	int total = 0;
    	u_char c;
    	char eb[2];
    	int cnt;

    	for (cnt = count; cnt > 0; p++, cnt--) {
    		if (user)
    			get_user(c, p);
    		else
    			c = *p;
    		total++;
    		if (c == m->mdmreg[REG_CR] || c == m->mdmreg[REG_LF]) {
    			/* Separator (CR oder 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)
    				isdn_tty_parse_at(info);
    			m->mdmcmdl = 0;
    			continue;
    		}
    		if (c == m->mdmreg[REG_BS] && m->mdmreg[REG_BS] < 128) {
    			/* Backspace-Funktion */
    			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 0:
    						if (c == 'A')
    							m->mdmcmd[m->mdmcmdl++] = c;
    						break;
    					case 1:
    						if (c == 'T')
    							m->mdmcmd[m->mdmcmdl++] = c;
    						break;
    					default:
    						m->mdmcmd[m->mdmcmdl++] = c;
    				}
    			}
    		}
    	}
    	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]))
    			if ((midx = dev->m_idx[i]) >= 0) {
    				modem_info *info = &dev->mdm.info[midx];
    				if (info->online) {
    					ton = 1;
    					if ((info->emu.pluscount == 3) &&
    					    ((jiffies - info->emu.lastplus) > PLUSWAIT2)) {
    						info->emu.pluscount = 0;
    						info->online = 0;
    						isdn_tty_modem_result(0, 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(2, 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);
    }