# isdn_common.c

    /* $Id$

     * Linux ISDN subsystem, common used functions (linklevel).
     *
     * Copyright 1994,95,96 by Fritz Elfert (fritz@wuemaus.franken.de)
     * Copyright 1995,96    Thinking Objects Software GmbH Wuerzburg
     * Copyright 1995,96    by Michael Hipp (Michael.Hipp@student.uni-tuebingen.de)
     *
     * 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 1.67  1998/06/26 15:12:21  fritz
     * Added handling of STAT_ICALL with incomplete CPN.
     * Added AT&L for ttyI emulator.
     * Added more locking stuff in tty_write.
     *
     * Revision 1.66  1998/06/17 19:50:41  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 1.65  1998/06/07 00:20:00  fritz
     * abc cleanup.
     *
     * Revision 1.64  1998/06/02 12:10:03  detabc
     * wegen einer einstweiliger verfuegung gegen DW ist zur zeit
     * die abc-extension bis zur klaerung der rechtslage nicht verfuegbar
     *
     * Revision 1.63  1998/05/03 17:40:38  detabc
     * Include abc-extension-support for >= 2.1.x Kernels in
     * isdn_net.c and isdn_common.c. alpha-test OK and running !
     *
     * Revision 1.62  1998/04/14 16:28:43  he
     * Fixed user space access with interrupts off and remaining
     * copy_{to,from}_user() -> -EFAULT return codes
     *
     * Revision 1.61  1998/03/22 18:50:46  hipp
     * Added BSD Compression for syncPPP .. UNTESTED at the moment
     *
     * Revision 1.60  1998/03/19 13:18:18  keil
     * Start of a CAPI like interface for supplementary Service
     * first service: SUSPEND
     *
     * Revision 1.59  1998/03/09 17:46:23  he
     * merged in 2.1.89 changes
     *
     * Revision 1.58  1998/03/07 22:35:24  fritz
     * Starting generic module support (Nothing usable yet).
     *
     * Revision 1.57  1998/03/07 18:21:01  cal
     * Dynamic Timeout-Rule-Handling vs. 971110 included
     *
     * Revision 1.56  1998/02/25 17:49:38  he
     * Changed return codes caused be failing copy_{to,from}_user to -EFAULT
     *
     * Revision 1.55  1998/02/23 23:35:32  fritz
     * Eliminated some compiler warnings.
     *
     * Revision 1.54  1998/02/22 19:44:19  fritz
     * Bugfixes and improvements regarding V.110, V.110 now running.
     *
     * Revision 1.53  1998/02/20 17:18:05  fritz
     * Changes for recent kernels.
     * Added common stub for sending commands to lowlevel.
     * Added V.110.
     *
     * Revision 1.52  1998/01/31 22:05:57  keil
     * Lots of changes for X.25 support:
     * Added generic support for connection-controlling encapsulation protocols
     * Added support of BHUP status message
     * Added support for additional p_encap X25IFACE
     * Added support for kernels >= 2.1.72
     *
     * Revision 1.51  1998/01/31 19:17:29  calle
     * merged changes from and for 2.1.82
     *
     * Revision 1.50  1997/12/12 06:12:11  calle
     * moved EXPORT_SYMBOL(register_isdn) from isdn_syms.c to isdn_common.c
     *
     * Revision 1.49  1997/11/06 17:16:52  keil
     * Sync to 2.1.62 changes
     *
     * Revision 1.48  1997/11/02 23:55:50  keil
     * Andi Kleen's changes for 2.1.60
     * without it the isdninfo and isdnctrl devices won't work
     *
     * Revision 1.47  1997/10/09 21:28:46  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 1.46  1997/10/01 09:20:27  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 1.45  1997/08/21 23:11:41  fritz
     * Added changes for kernels >= 2.1.45
     *
     * Revision 1.44  1997/05/27 15:17:23  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 1.43  1997/03/31 14:09:43  fritz
     * Fixed memory leak in isdn_close().
     *
     * Revision 1.42  1997/03/30 16:51:08  calle
     * changed calls to copy_from_user/copy_to_user and removed verify_area
     * were possible.
     *
     * Revision 1.41  1997/03/24 22:54:41  fritz
     * Some small fixes in debug code.
     *
     * Revision 1.40  1997/03/08 08:13:51  fritz
     * Bugfix: IIOCSETMAP (Set mapping) was broken.
     *
     * Revision 1.39  1997/03/07 01:32:54  fritz
     * Added proper ifdef's for CONFIG_ISDN_AUDIO
     *
     * Revision 1.38  1997/03/05 21:15:02  fritz
     * Fix: reduced stack usage of isdn_ioctl() and isdn_set_allcfg()
     *
     * Revision 1.37  1997/03/02 14:29:18  fritz
     * More ttyI related cleanup.
     *
     * Revision 1.36  1997/02/28 02:32:40  fritz
     * Cleanup: Moved some tty related stuff from isdn_common.c
     *          to isdn_tty.c
     * Bugfix:  Bisync protocol did not behave like documented.
     *
     * Revision 1.35  1997/02/21 13:01:19  fritz
     * Changes CAUSE message output in kernel log.
     *
     * Revision 1.34  1997/02/10 20:12:43  fritz
     * Changed interface for reporting incoming calls.
     *
     * Revision 1.33  1997/02/10 10:05:42  fritz
     * More changes for Kernel 2.1.X
     * Symbol information moved to isdn_syms.c
     *
     * Revision 1.32  1997/02/03 22:55:26  fritz
     * Reformatted according CodingStyle.
     * Changed isdn_writebuf_stub static.
     * Slow down tty-RING counter.
     * skb->free stuff replaced by macro.
     * Bugfix in audio-skb locking.
     * Bugfix in HL-driver locking.
     *
     * Revision 1.31  1997/01/17 01:19:18  fritz
     * Applied chargeint patch.
     *
     * Revision 1.30  1997/01/14 01:27:47  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 1.29  1997/01/12 23:33:03  fritz
     * Made isdn_all_eaz foolproof.
     *
     * Revision 1.28  1996/11/13 02:33:19  fritz
     * Fixed a race condition.
     *
     * Revision 1.27  1996/10/27 22:02:41  keil
     * return codes for ISDN_STAT_ICALL
     *
     * Revision 1.26  1996/10/23 11:59:40  fritz
     * More compatibility changes.
     *
     * Revision 1.25  1996/10/22 23:13:54  fritz
     * Changes for compatibility to 2.0.X and 2.1.X kernels.
     *
     * Revision 1.24  1996/10/11 14:02:03  fritz
     * Bugfix: call to isdn_ppp_timer_timeout() never compiled, because of
     *         typo in #ifdef.
     *
     * Revision 1.23  1996/06/25 18:35:38  fritz
     * Fixed bogus memory access in isdn_set_allcfg().
     *
     * Revision 1.22  1996/06/24 17:37:37  fritz
     * Bugfix: isdn_timer_ctrl() did restart timer, even if it
     *         was already running.
     *         lowlevel driver locking did use wrong parameters.
     *
     * Revision 1.21  1996/06/15 14:58:20  fritz
     * Added version signatures for data structures used
     * by userlevel programs.
     *
     * Revision 1.20  1996/06/12 16:01:49  fritz
     * Bugfix: Remote B-channel hangup sometimes did not result
     *         in a NO CARRIER on tty.
     *
     * Revision 1.19  1996/06/11 14:52:04  hipp
     * minor bugfix in isdn_writebuf_skb_stub()
     *
     * Revision 1.18  1996/06/06 14:51:51  fritz
     * Changed to support DTMF decoding on audio playback also.
     *
     * Revision 1.17  1996/06/05 02:24:10  fritz
     * Added DTMF decoder for audio mode.
     *
     * Revision 1.16  1996/06/03 20:09:05  fritz
     * Bugfix: called wrong function pointer for locking in
     *         isdn_get_free_channel().
     *
     * Revision 1.15  1996/05/31 01:10:54  fritz
     * Bugfixes:
     *   Lowlevel modules did not get locked correctly.
     *   Did show wrong revision when initializing.
     *   Minor fixes in ioctl code.
     *   sk_buff did not get freed, if error in writebuf_stub.
     *
     * Revision 1.14  1996/05/18 01:36:55  fritz
     * Added spelling corrections and some minor changes
     * to stay in sync with kernel.
     *
     * Revision 1.13  1996/05/17 15:43:30  fritz
     * Bugfix: decrement of rcvcount in readbchan() corrected.
     *
     * Revision 1.12  1996/05/17 03:55:43  fritz
     * Changed DLE handling for audio receive.
     * Some cleanup.
     * Added display of isdn_audio_revision.
     *
     * Revision 1.11  1996/05/11 21:51:32  fritz
     * Changed queue management to use sk_buffs.
     *
     * Revision 1.10  1996/05/10 08:49:16  fritz
     * Checkin before major changes of tty-code.
     *
     * Revision 1.9  1996/05/07 09:19:41  fritz
     * Adapted to changes in isdn_tty.c
     *
     * Revision 1.8  1996/05/06 11:34:51  hipp
     * fixed a few bugs
     *
     * Revision 1.7  1996/05/02 03:55:17  fritz
     * Bugfixes:
     *  - B-channel connect message for modem devices
     *    sometimes did not result in a CONNECT-message.
     *  - register_isdn did not check for driverId-conflicts.
     *
     * Revision 1.6  1996/04/30 20:57:21  fritz
     * Commit test
     *
     * Revision 1.5  1996/04/20 16:19:07  fritz
     * Changed slow timer handlers to increase accuracy.
     * Added statistic information for usage by xisdnload.
     * Fixed behaviour of isdnctrl-device on non-blocked io.
     * Fixed all io to go through generic writebuf-function without
     * bypassing. Same for incoming data.
     * Fixed bug: Last channel had been unusable.
     * Fixed kfree of tty xmit_buf on ppp initialization failure.
     *
     * Revision 1.4  1996/02/11 02:33:26  fritz
     * Fixed bug in main timer-dispatcher.
     * Bugfix: Lot of tty-callbacks got called regardless of the events already
     * been handled by network-devices.
     * Changed ioctl-names.
     *
     * Revision 1.3  1996/01/22 05:16:11  fritz
     * Changed ioctl-names.
     * Fixed bugs in isdn_open and isdn_close regarding PPP_MINOR.
     *
     * Revision 1.2  1996/01/21 16:52:40  fritz
     * Support for sk_buffs added, changed header-stuffing.
     *
     * Revision 1.1  1996/01/09 04:12:52  fritz
     * Initial revision
     *
     */

    #include <linux/config.h>
    #include <linux/module.h>
    #include <linux/version.h>
    #include <linux/poll.h>
    #include <linux/isdn.h>
    #include "isdn_common.h"
    #include "isdn_tty.h"
    #include "isdn_net.h"
    #include "isdn_ppp.h"
    #ifdef CONFIG_ISDN_AUDIO
    #include "isdn_audio.h"
    #endif
    #include "isdn_v110.h"
    #include "isdn_cards.h"

    /* Debugflags */
    #undef ISDN_DEBUG_STATCALLB

    isdn_dev *dev = (isdn_dev *) 0;

    static char *isdn_revision = "$Revision$";

    extern char *isdn_net_revision;
    extern char *isdn_tty_revision;
    #ifdef CONFIG_ISDN_PPP
    extern char *isdn_ppp_revision;
    #else
    static char *isdn_ppp_revision = ": none $";
    #endif
    #ifdef CONFIG_ISDN_AUDIO
    extern char *isdn_audio_revision;
    #else
    static char *isdn_audio_revision = ": none $";
    #endif
    extern char *isdn_v110_revision;

    static int isdn_writebuf_stub(int, int, const u_char *, int, int);

    void
    isdn_MOD_INC_USE_COUNT(void)
    {
    	MOD_INC_USE_COUNT;
    }

    void
    isdn_MOD_DEC_USE_COUNT(void)
    {
    	MOD_DEC_USE_COUNT;
    }

    #if defined(ISDN_DEBUG_NET_DUMP) || defined(ISDN_DEBUG_MODEM_DUMP) || defined(CONFIG_ISDN_TIMEOUT_RULES)
    void
    isdn_dumppkt(char *s, u_char * p, int len, int dumplen)
    {
    	int dumpc;

    	printk(KERN_DEBUG "%s(%d) ", s, len);
    	for (dumpc = 0; (dumpc < dumplen) && (len); len--, dumpc++)
    		printk(" %02x", *p++);
    	printk("\n");
    }
    #endif

    /*
     * I picked the pattern-matching-functions from an old GNU-tar version (1.10)
     * It was originally written and put to PD by rs@mirror.TMC.COM (Rich Salz)
     */
    static int
    isdn_star(char *s, char *p)
    {
    	while (isdn_wildmat(s, p)) {
    		if (*++s == '\0')
    			return (2);
    	}
    	return (0);
    }

    /*
     * Shell-type Pattern-matching for incoming caller-Ids
     * This function gets a string in s and checks, if it matches the pattern
     * given in p.
     *
     * Return:
     *   0 = match.
     *   1 = no match.
     *   2 = no match. Would eventually match, if s would be longer.
     *
     * Possible Patterns:
     *
     * '?'     matches one character
     * '*'     matches zero or more characters
     * [xyz]   matches the set of characters in brackets.
     * [^xyz]  matches any single character not in the set of characters
     */

    int
    isdn_wildmat(char *s, char *p)
    {
    	register int last;
    	register int matched;
    	register int reverse;
    	register int nostar = 1;

    	for (; *p; s++, p++)
    		switch (*p) {
    			case '\\':
    				/*
    				 * Literal match with following character,
    				 * fall through.
    				 */
    				p++;
    			default:
    				if (*s != *p)
    					return (*s == '\0')?2:1;
    				continue;
    			case '?':
    				/* Match anything. */
    				if (*s == '\0')
    					return (2);
    				continue;
    			case '*':
    				nostar = 0;
    				/* Trailing star matches everything. */
    				return (*++p ? isdn_star(s, p) : 0);
    			case '[':
    				/* [^....] means inverse character class. */
    				if ((reverse = (p[1] == '^')))
    					p++;
    				for (last = 0, matched = 0; *++p && (*p != ']'); last = *p)
    					/* This next line requires a good C compiler. */
    					if (*p == '-' ? *s <= *++p && *s >= last : *s == *p)
    						matched = 1;
    				if (matched == reverse)
    					return (1);
    				continue;
    		}
    	return (*s == '\0')?0:nostar;
    }

    static void
    isdn_free_queue(struct sk_buff_head *queue)
    {
    	struct sk_buff *skb;
    	unsigned long flags;

    	save_flags(flags);
    	cli();
    	if (skb_queue_len(queue))
    		while ((skb = skb_dequeue(queue)))
    			dev_kfree_skb(skb);
    	restore_flags(flags);
    }

    int
    isdn_dc2minor(int di, int ch)
    {
    	int i;
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    		if (dev->chanmap[i] == ch && dev->drvmap[i] == di)
    			return i;
    	return -1;
    }

    static int isdn_timer_cnt1 = 0;
    static int isdn_timer_cnt2 = 0;
    static int isdn_timer_cnt3 = 0;
    static int isdn_timer_cnt4 = 0;

    static void
    isdn_timer_funct(ulong dummy)
    {
    	int tf = dev->tflags;
    	if (tf & ISDN_TIMER_FAST) {
    		if (tf & ISDN_TIMER_MODEMREAD)
    			isdn_tty_readmodem();
    		if (tf & ISDN_TIMER_MODEMPLUS)
    			isdn_tty_modem_escape();
    		if (tf & ISDN_TIMER_MODEMXMIT)
    			isdn_tty_modem_xmit();
    	}
    	if (tf & ISDN_TIMER_SLOW) {
    		if (++isdn_timer_cnt1 >= ISDN_TIMER_02SEC) {
    			isdn_timer_cnt1 = 0;
    			if (tf & ISDN_TIMER_NETDIAL)
    				isdn_net_dial();
    		}
    		if (++isdn_timer_cnt2 >= ISDN_TIMER_1SEC) {
    			isdn_timer_cnt2 = 0;
    			if (tf & ISDN_TIMER_NETHANGUP)
    				isdn_net_autohup();
    			if (++isdn_timer_cnt3 > ISDN_TIMER_RINGING) {
    				isdn_timer_cnt3 = 0;
    				if (tf & ISDN_TIMER_MODEMRING)
    					isdn_tty_modem_ring();
    			}
    			if (++isdn_timer_cnt4 > ISDN_TIMER_KEEPINT) {
    				isdn_timer_cnt4 = 0;
    				if (tf & ISDN_TIMER_KEEPALIVE)
    					isdn_net_slarp_out();
    			}
    #if (defined CONFIG_ISDN_PPP) && (defined CONFIG_ISDN_MPP)
    			if (tf & ISDN_TIMER_IPPP)
    				isdn_ppp_timer_timeout();
    #endif
    		}
    	}
    	if (tf)
    	{
    		int flags;

    		save_flags(flags);
    		cli();
    		del_timer(&dev->timer);
    		dev->timer.expires = jiffies + ISDN_TIMER_RES;
    		add_timer(&dev->timer);
    		restore_flags(flags);
    	}
    }

    void
    isdn_timer_ctrl(int tf, int onoff)
    {
    	int flags;

    	save_flags(flags);
    	cli();
    	if ((tf & ISDN_TIMER_SLOW) && (!(dev->tflags & ISDN_TIMER_SLOW))) {
    		/* If the slow-timer wasn't activated until now */
    		isdn_timer_cnt1 = 0;
    		isdn_timer_cnt2 = 0;
    	}
    	if (onoff)
    		dev->tflags |= tf;
    	else
    		dev->tflags &= ~tf;
    	if (dev->tflags) {
    		if (!del_timer(&dev->timer))	/* del_timer is 1, when active */
    			dev->timer.expires = jiffies + ISDN_TIMER_RES;
    		add_timer(&dev->timer);
    	}
    	restore_flags(flags);
    }

    /*
     * Receive a packet from B-Channel. (Called from low-level-module)
     */
    static void
    isdn_receive_skb_callback(int di, int channel, struct sk_buff *skb)
    {
    	int i;

    	if ((i = isdn_dc2minor(di, channel)) == -1) {
    		dev_kfree_skb(skb);
    		return;
    	}
    	/* Update statistics */
    	dev->ibytes[i] += skb->len;

    	/* First, try to deliver data to network-device */
    	if (isdn_net_rcv_skb(i, skb))
    		return;

    	/* V.110 handling
    	 * makes sense for async streams only, so it is
    	 * called after possible net-device delivery.
    	 */
    	if (dev->v110[i]) {
    		atomic_inc(&dev->v110use[i]);
    		skb = isdn_v110_decode(dev->v110[i], skb);
    		atomic_dec(&dev->v110use[i]);
    		if (!skb)
    			return;
    	}

    	/* No network-device found, deliver to tty or raw-channel */
    	if (skb->len) {
    		if (isdn_tty_rcv_skb(i, di, channel, skb))
    			return;
    		wake_up_interruptible(&dev->drv[di]->rcv_waitq[channel]);
    	} else
    		dev_kfree_skb(skb);
    }

    /*
     * Intercept command from Linklevel to Lowlevel.
     * If layer 2 protocol is V.110 and this is not supported by current
     * lowlevel-driver, use driver's transparent mode and handle V.110 in
     * linklevel instead.
     */
    int
    isdn_command(isdn_ctrl *cmd)
    {
    	if (cmd->command == ISDN_CMD_SETL2) {
    			int idx = isdn_dc2minor(cmd->driver, cmd->arg & 255);
    			unsigned long l2prot = (cmd->arg >> 8) & 255;
    			unsigned long features = (dev->drv[cmd->driver]->interface->features
    						 >> ISDN_FEATURE_L2_SHIFT) &
    				ISDN_FEATURE_L2_MASK;
    			unsigned long l2_feature = (1 << l2prot);

    			switch (l2prot) {
    				case ISDN_PROTO_L2_V11096:
    				case ISDN_PROTO_L2_V11019:
    				case ISDN_PROTO_L2_V11038:
    						/* If V.110 requested, but not supported by
    						 * HL-driver, set emulator-flag and change
    						 * Layer-2 to transparent
    						 */
    					if (!(features & l2_feature)) {
    						dev->v110emu[idx] = l2prot;
    						cmd->arg = (cmd->arg & 255) |
    								   (ISDN_PROTO_L2_TRANS << 8);
    					} else
    						dev->v110emu[idx] = 0;
    			}
    	}
    	return dev->drv[cmd->driver]->interface->command(cmd);
    }

    void
    isdn_all_eaz(int di, int ch)
    {
    	isdn_ctrl cmd;

    	if (di < 0)
    		return;
    	cmd.driver = di;
    	cmd.arg = ch;
    	cmd.command = ISDN_CMD_SETEAZ;
    	cmd.parm.num[0] = '\0';
    	isdn_command(&cmd);
    }

    /*
     * Begin of a CAPI like LL<->HL 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_capi_rec_hl_msg(capi_msg *cm) {

    	int di;
    	int ch;

    	di = (cm->adr.Controller & 0x7f) -1;
    	ch = isdn_dc2minor(di, (cm->adr.Controller>>8)& 0x7f);
    	switch(cm->Command) {
    		case CAPI_FACILITY:
    			/* in the moment only handled in tty */
    			return(isdn_tty_capi_facility(cm));
    		default:
    			return(-1);
    	}
    }

    static int
    isdn_status_callback(isdn_ctrl * c)
    {
    	int di;
    	ulong flags;
    	int i;
    	int r;
    	int retval = 0;
    	isdn_ctrl cmd;

    	di = c->driver;
    	i = isdn_dc2minor(di, c->arg);
    	switch (c->command) {
    		case ISDN_STAT_BSENT:
    			if (i < 0)
    				return -1;
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			if (isdn_net_stat_callback(i, c))
    				return 0;
    			if (isdn_v110_stat_callback(i, c))
    				return 0;
    			if (isdn_tty_stat_callback(i, c))
    				return 0;
    			wake_up_interruptible(&dev->drv[di]->snd_waitq[c->arg]);
    			break;
    		case ISDN_STAT_STAVAIL:
    			save_flags(flags);
    			cli();
    			dev->drv[di]->stavail += c->arg;
    			restore_flags(flags);
    			wake_up_interruptible(&dev->drv[di]->st_waitq);
    			break;
    		case ISDN_STAT_RUN:
    			dev->drv[di]->running = 1;
    			for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    				if (dev->drvmap[i] == di)
    					isdn_all_eaz(di, dev->chanmap[i]);
    			break;
    		case ISDN_STAT_STOP:
    			dev->drv[di]->running = 0;
    			break;
    		case ISDN_STAT_ICALL:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "ICALL (net): %d %ld %s\n", di, c->arg, c->parm.num);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED) {
    				cmd.driver = di;
    				cmd.arg = c->arg;
    				cmd.command = ISDN_CMD_HANGUP;
    				isdn_command(&cmd);
    				return 0;
    			}
    			/* Try to find a network-interface which will accept incoming call */
    			cmd.driver = di;
    			cmd.arg = c->arg;
    			cmd.command = ISDN_CMD_LOCK;
    			isdn_command(&cmd);
    			r = isdn_net_find_icall(di, c->arg, i, c->parm.setup);
    			switch (r) {
    				case 0:
    					/* No network-device replies.
    					 * Try ttyI's.
    					 * These return 0 on no match, 1 on match and
    					 * 3 on eventually match, if CID is longer.
    					 */
    					retval = isdn_tty_find_icall(di, c->arg, c->parm.setup);
    					if ((!retval) && dev->drv[di]->reject_bus) {
    						/* No tty responding */
    						cmd.driver = di;
    						cmd.arg = c->arg;
    						cmd.command = ISDN_CMD_HANGUP;
    						isdn_command(&cmd);
    						retval = 2;
    					}
    					break;
    				case 1:
    					/* Schedule connection-setup */
    					isdn_net_dial();
    					cmd.driver = di;
    					cmd.arg = c->arg;
    					cmd.command = ISDN_CMD_ACCEPTD;
    					isdn_command(&cmd);
    					retval = 1;
    					break;
    				case 2:	/* For calling back, first reject incoming call ... */
    				case 3:	/* Interface found, but down, reject call actively  */
    					retval = 2;
    					printk(KERN_INFO "isdn: Rejecting Call\n");
    					cmd.driver = di;
    					cmd.arg = c->arg;
    					cmd.command = ISDN_CMD_HANGUP;
    					isdn_command(&cmd);
    					if (r == 3)
    						break;
    					/* Fall through */
    				case 4:
    					/* ... then start callback. */
    					isdn_net_dial();
    					break;
    				case 5:
    					/* Number would eventually match, if longer */
    					retval = 3;
    					break;
    			}
    			if (retval != 1) {
    				cmd.driver = di;
    				cmd.arg = c->arg;
    				cmd.command = ISDN_CMD_UNLOCK;
    				isdn_command(&cmd);
    			}
    			printk(KERN_DEBUG "ICALL: ret=%d\n", retval);
    			return retval;
    			break;
    		case ISDN_STAT_CINF:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "CINF: %ld %s\n", c->arg, c->parm.num);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			if (strcmp(c->parm.num, "0"))
    				isdn_net_stat_callback(i, c);
    			isdn_tty_stat_callback(i, c);
    			break;
    		case ISDN_STAT_CAUSE:
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "CAUSE: %ld %s\n", c->arg, c->parm.num);
    #endif
    			printk(KERN_INFO "isdn: %s,ch%ld cause: %s\n",
    			       dev->drvid[di], c->arg, c->parm.num);
    			isdn_tty_stat_callback(i, c);
    			break;
    		case ISDN_STAT_DCONN:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "DCONN: %ld\n", c->arg);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			/* Find any net-device, waiting for D-channel setup */
    			if (isdn_net_stat_callback(i, c))
    				break;
    			isdn_v110_stat_callback(i, c);
    			/* Find any ttyI, waiting for D-channel setup */
    			if (isdn_tty_stat_callback(i, c)) {
    				cmd.driver = di;
    				cmd.arg = c->arg;
    				cmd.command = ISDN_CMD_ACCEPTB;
    				isdn_command(&cmd);
    				break;
    			}
    			break;
    		case ISDN_STAT_DHUP:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "DHUP: %ld\n", c->arg);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			dev->drv[di]->flags &= ~(1 << (c->arg));
    			isdn_info_update();
    			/* Signal hangup to network-devices */
    			if (isdn_net_stat_callback(i, c))
    				break;
    			isdn_v110_stat_callback(i, c);
    			if (isdn_tty_stat_callback(i, c))
    				break;
    			break;
    		case ISDN_STAT_BCONN:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "BCONN: %ld\n", c->arg);
    #endif
    			/* Signal B-channel-connect to network-devices */
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			dev->drv[di]->flags |= (1 << (c->arg));
    			isdn_info_update();
    			if (isdn_net_stat_callback(i, c))
    				break;
    			isdn_v110_stat_callback(i, c);
    			if (isdn_tty_stat_callback(i, c))
    				break;
    			break;
    		case ISDN_STAT_BHUP:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "BHUP: %ld\n", c->arg);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			dev->drv[di]->flags &= ~(1 << (c->arg));
    			isdn_info_update();
    #ifdef CONFIG_ISDN_X25
    			/* Signal hangup to network-devices */
    			if (isdn_net_stat_callback(i, c))
    				break;
    #endif
    			isdn_v110_stat_callback(i, c);
    			if (isdn_tty_stat_callback(i, c))
    				break;
    			break;
    		case ISDN_STAT_NODCH:
    			if (i < 0)
    				return -1;
    #ifdef ISDN_DEBUG_STATCALLB
    			printk(KERN_DEBUG "NODCH: %ld\n", c->arg);
    #endif
    			if (dev->global_flags & ISDN_GLOBAL_STOPPED)
    				return 0;
    			if (isdn_net_stat_callback(i, c))
    				break;
    			if (isdn_tty_stat_callback(i, c))
    				break;
    			break;
    		case ISDN_STAT_ADDCH:
    			break;
    		case ISDN_STAT_UNLOAD:
    			save_flags(flags);
    			cli();
    			isdn_tty_stat_callback(i, c);
    			for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    				if (dev->drvmap[i] == di) {
    					dev->drvmap[i] = -1;
    					dev->chanmap[i] = -1;
    				}
    			dev->drivers--;
    			dev->channels -= dev->drv[di]->channels;
    			kfree(dev->drv[di]->rcverr);
    			kfree(dev->drv[di]->rcvcount);
    			for (i = 0; i < dev->drv[di]->channels; i++)
    				isdn_free_queue(&dev->drv[di]->rpqueue[i]);
    			kfree(dev->drv[di]->rpqueue);
    			kfree(dev->drv[di]->rcv_waitq);
    			kfree(dev->drv[di]->snd_waitq);
    			kfree(dev->drv[di]);
    			dev->drv[di] = NULL;
    			dev->drvid[di][0] = '\0';
    			isdn_info_update();
    			restore_flags(flags);
    			return 0;
    		case ISDN_STAT_L1ERR:
    			break;
    		case CAPI_PUT_MESSAGE:
    			return(isdn_capi_rec_hl_msg(&c->parm.cmsg));
    		default:
    			return -1;
    	}
    	return 0;
    }

    /*
     * Get integer from char-pointer, set pointer to end of number
     */
    int
    isdn_getnum(char **p)
    {
    	int v = -1;

    	while (*p[0] >= '0' && *p[0] <= '9')
    		v = ((v < 0) ? 0 : (v * 10)) + (int) ((*p[0]++) - '0');
    	return v;
    }

    #define DLE 0x10

    /*
     * isdn_readbchan() tries to get data from the read-queue.
     * It MUST be called with interrupts off.
     *
     * Be aware that this is not an atomic operation when sleep != 0, even though
     * interrupts are turned off! Well, like that we are currently only called
     * on behalf of a read system call on raw device files (which are documented
     * to be dangerous and for for debugging purpose only). The inode semaphore
     * takes care that this is not called for the same minor device number while
     * we are sleeping, but access is not serialized against simultaneous read()
     * from the corresponding ttyI device. Can other ugly events, like changes
     * of the mapping (di,ch)<->minor, happen during the sleep? --he
     */
    int
    isdn_readbchan(int di, int channel, u_char * buf, u_char * fp, int len, struct wait_queue **sleep)
    {
    	int left;
    	int count;
    	int count_pull;
    	int count_put;
    	int dflag;
    	struct sk_buff *skb;
    	u_char *cp;

    	if (!dev->drv[di])
    		return 0;
    	if (skb_queue_empty(&dev->drv[di]->rpqueue[channel])) {
    		if (sleep)
    			interruptible_sleep_on(sleep);
    		else
    			return 0;
    	}
    	left = MIN(len, dev->drv[di]->rcvcount[channel]);
    	cp = buf;
    	count = 0;
    	while (left) {
    		if (!(skb = skb_peek(&dev->drv[di]->rpqueue[channel])))
    			break;
    #ifdef CONFIG_ISDN_AUDIO
    		if (ISDN_AUDIO_SKB_LOCK(skb))
    			break;
    		ISDN_AUDIO_SKB_LOCK(skb) = 1;
    		if (ISDN_AUDIO_SKB_DLECOUNT(skb)) {
    			char *p = skb->data;
    			unsigned long DLEmask = (1 << channel);

    			dflag = 0;
    			count_pull = count_put = 0;
    			while ((count_pull < skb->len) && (left-- > 0)) {
    				if (dev->drv[di]->DLEflag & DLEmask) {
    					*cp++ = DLE;
    					dev->drv[di]->DLEflag &= ~DLEmask;
    				} else {
    					*cp++ = *p;
    					if (*p == DLE) {
    						dev->drv[di]->DLEflag |= DLEmask;
    						(ISDN_AUDIO_SKB_DLECOUNT(skb))--;
    					}
    					p++;
    					count_pull++;
    				}
    				count_put++;
    			}
    			if (count_pull >= skb->len)
    				dflag = 1;
    		} else {
    #endif
    			/* No DLE's in buff, so simply copy it */
    			dflag = 1;
    			if ((count_pull = skb->len) > left) {
    				count_pull = left;
    				dflag = 0;
    			}
    			count_put = count_pull;
    			memcpy(cp, skb->data, count_put);
    			cp += count_put;
    			left -= count_put;
    #ifdef CONFIG_ISDN_AUDIO
    		}
    #endif
    		count += count_put;
    		if (fp) {
    			memset(fp, 0, count_put);
    			fp += count_put;
    		}
    		if (dflag) {
    			/* We got all the data in this buff.
    			 * Now we can dequeue it.
    			 */
    			if (fp)
    				*(fp - 1) = 0xff;
    #ifdef CONFIG_ISDN_AUDIO
    			ISDN_AUDIO_SKB_LOCK(skb) = 0;
    #endif
    			skb = skb_dequeue(&dev->drv[di]->rpqueue[channel]);
    			dev_kfree_skb(skb);
    		} else {
    			/* Not yet emptied this buff, so it
    			 * must stay in the queue, for further calls
    			 * but we pull off the data we got until now.
    			 */
    			skb_pull(skb, count_pull);
    #ifdef CONFIG_ISDN_AUDIO
    			ISDN_AUDIO_SKB_LOCK(skb) = 0;
    #endif
    		}
    		dev->drv[di]->rcvcount[channel] -= count_put;
    	}
    	return count;
    }

    static __inline int
    isdn_minor2drv(int minor)
    {
    	return (dev->drvmap[minor]);
    }

    static __inline int
    isdn_minor2chan(int minor)
    {
    	return (dev->chanmap[minor]);
    }

    static char *
    isdn_statstr(void)
    {
    	static char istatbuf[2048];
    	char *p;
    	int i;

    	sprintf(istatbuf, "idmap:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		sprintf(p, "%s ", (dev->drvmap[i] < 0) ? "-" : dev->drvid[dev->drvmap[i]]);
    		p = istatbuf + strlen(istatbuf);
    	}
    	sprintf(p, "\nchmap:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		sprintf(p, "%d ", dev->chanmap[i]);
    		p = istatbuf + strlen(istatbuf);
    	}
    	sprintf(p, "\ndrmap:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		sprintf(p, "%d ", dev->drvmap[i]);
    		p = istatbuf + strlen(istatbuf);
    	}
    	sprintf(p, "\nusage:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		sprintf(p, "%d ", dev->usage[i]);
    		p = istatbuf + strlen(istatbuf);
    	}
    	sprintf(p, "\nflags:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_DRIVERS; i++) {
    		if (dev->drv[i]) {
    			sprintf(p, "%ld ", dev->drv[i]->flags);
    			p = istatbuf + strlen(istatbuf);
    		} else {
    			sprintf(p, "? ");
    			p = istatbuf + strlen(istatbuf);
    		}
    	}
    	sprintf(p, "\nphone:\t");
    	p = istatbuf + strlen(istatbuf);
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		sprintf(p, "%s ", dev->num[i]);
    		p = istatbuf + strlen(istatbuf);
    	}
    	sprintf(p, "\n");
    	return istatbuf;
    }

    /* Module interface-code */

    void
    isdn_info_update(void)
    {
    	infostruct *p = dev->infochain;

    	while (p) {
    		*(p->private) = 1;
    		p = (infostruct *) p->next;
    	}
    	wake_up_interruptible(&(dev->info_waitq));
    }

    static ssize_t
    isdn_read(struct file *file, char *buf, size_t count, loff_t * off)
    {
    	uint minor = MINOR(file->f_dentry->d_inode->i_rdev);
    	int len = 0;
    	ulong flags;
    	int drvidx;
    	int chidx;
    	char *p;

    	if (off != &file->f_pos)
    		return -ESPIPE;

    	if (minor == ISDN_MINOR_STATUS) {
    		if (!file->private_data) {
    			if (file->f_flags & O_NONBLOCK)
    				return -EAGAIN;
    			interruptible_sleep_on(&(dev->info_waitq));
    		}
    		p = isdn_statstr();
    		file->private_data = 0;
    		if ((len = strlen(p)) <= count) {
    			if (copy_to_user(buf, p, len))
    				return -EFAULT;
    			*off += len;
    			return len;
    		}
    		return 0;
    	}
    	if (!dev->drivers)
    		return -ENODEV;
    	if (minor < ISDN_MINOR_CTRL) {
    		drvidx = isdn_minor2drv(minor);
    		if (drvidx < 0)
    			return -ENODEV;
    		if (!dev->drv[drvidx]->running)
    			return -ENODEV;
    		chidx = isdn_minor2chan(minor);
    		if(  ! (p = kmalloc(count,GFP_KERNEL))  ) return -ENOMEM;
    		save_flags(flags);
    		cli();
    		len = isdn_readbchan(drvidx, chidx, p, 0, count,
    				     &dev->drv[drvidx]->rcv_waitq[chidx]);
    		*off += len;
    		restore_flags(flags);
    		if( copy_to_user(buf,p,len) ) len = -EFAULT;
    		kfree(p);
    		return len;
    	}
    	if (minor <= ISDN_MINOR_CTRLMAX) {
    		drvidx = isdn_minor2drv(minor - ISDN_MINOR_CTRL);
    		if (drvidx < 0)
    			return -ENODEV;
    		if (!dev->drv[drvidx]->stavail) {
    			if (file->f_flags & O_NONBLOCK)
    				return -EAGAIN;
    			interruptible_sleep_on(&(dev->drv[drvidx]->st_waitq));
    		}
    		if (dev->drv[drvidx]->interface->readstat)
    			len = dev->drv[drvidx]->interface->
    			    readstat(buf, MIN(count, dev->drv[drvidx]->stavail),
    				     1, drvidx, isdn_minor2chan(minor));
    		else
    			len = 0;
    		save_flags(flags);
    		cli();
    		if (len)
    			dev->drv[drvidx]->stavail -= len;
    		else
    			dev->drv[drvidx]->stavail = 0;
    		restore_flags(flags);
    		*off += len;
    		return len;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX)
    		return (isdn_ppp_read(minor - ISDN_MINOR_PPP, file, buf, count));
    #endif
    	return -ENODEV;
    }

    static loff_t
    isdn_lseek(struct file *file, loff_t offset, int orig)
    {
    	return -ESPIPE;
    }

    static ssize_t
    isdn_write(struct file *file, const char *buf, size_t count, loff_t * off)
    {
    	uint minor = MINOR(file->f_dentry->d_inode->i_rdev);
    	int drvidx;
    	int chidx;

    	if (off != &file->f_pos)
    		return -ESPIPE;

    	if (minor == ISDN_MINOR_STATUS)
    		return -EPERM;
    	if (!dev->drivers)
    		return -ENODEV;
    	if (minor < ISDN_MINOR_CTRL) {
    		drvidx = isdn_minor2drv(minor);
    		if (drvidx < 0)
    			return -ENODEV;
    		if (!dev->drv[drvidx]->running)
    			return -ENODEV;
    		chidx = isdn_minor2chan(minor);
    		while (isdn_writebuf_stub(drvidx, chidx, buf, count, 1) != count)
    			interruptible_sleep_on(&dev->drv[drvidx]->snd_waitq[chidx]);
    		return count;
    	}
    	if (minor <= ISDN_MINOR_CTRLMAX) {
    		drvidx = isdn_minor2drv(minor - ISDN_MINOR_CTRL);
    		if (drvidx < 0)
    			return -ENODEV;
    		/*
    		 * We want to use the isdnctrl device to load the firmware
    		 *
    		 if (!dev->drv[drvidx]->running)
    		 return -ENODEV;
    		 */
    		if (dev->drv[drvidx]->interface->writecmd)
    			return (dev->drv[drvidx]->interface->
    				writecmd(buf, count, 1, drvidx, isdn_minor2chan(minor)));
    		else
    			return count;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX)
    		return (isdn_ppp_write(minor - ISDN_MINOR_PPP, file, buf, count));
    #endif
    	return -ENODEV;
    }

    static unsigned int
    isdn_poll(struct file *file, poll_table * wait)
    {
    	unsigned int mask = 0;
    	unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev);
    	int drvidx = isdn_minor2drv(minor - ISDN_MINOR_CTRL);

    	if (minor == ISDN_MINOR_STATUS) {
    		poll_wait(file, &(dev->info_waitq), wait);
    		/* mask = POLLOUT | POLLWRNORM; */
    		if (file->private_data) {
    			mask |= POLLIN | POLLRDNORM;
    		}
    		return mask;
    	}
    	if (minor >= ISDN_MINOR_CTRL && minor <= ISDN_MINOR_CTRLMAX) {
    		poll_wait(file, &(dev->drv[drvidx]->st_waitq), wait);
    		if (drvidx < 0) {
    			printk(KERN_ERR "isdn_common: isdn_poll 1 -> what the hell\n");
    			return POLLERR;
    		}
    		mask = POLLOUT | POLLWRNORM;
    		if (dev->drv[drvidx]->stavail) {
    			mask |= POLLIN | POLLRDNORM;
    		}
    		return mask;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX)
    		return (isdn_ppp_poll(file, wait));
    #endif
    	printk(KERN_ERR "isdn_common: isdn_poll 2 -> what the hell\n");
    	return POLLERR;
    }

    static int
    isdn_ioctl(struct inode *inode, struct file *file, uint cmd, ulong arg)
    {
    	uint minor = MINOR(inode->i_rdev);
    	isdn_ctrl c;
    	int drvidx;
    	int chidx;
    	int ret;
    	int i;
    	char *p;
    	char *s;
    	union iocpar {
    		char name[10];
    		char bname[22];
    		isdn_ioctl_struct iocts;
    		isdn_net_ioctl_phone phone;
    		isdn_net_ioctl_cfg cfg;
    #ifdef CONFIG_ISDN_TIMEOUT_RULES
    		isdn_ioctl_timeout_rule	timru;
    #endif /* CONFIG_ISDN_TIMEOUT_RULES */
    #ifdef CONFIG_ISDN_BUDGET
    		isdn_ioctl_budget	budget;
    #endif /* CONFIG_ISDN_BUDGET */
    	} iocpar;

    #define name  iocpar.name
    #define bname iocpar.bname
    #define iocts iocpar.iocts
    #define phone iocpar.phone
    #define cfg   iocpar.cfg
    #ifdef CONFIG_ISDN_TIMEOUT_RULES
    #	define	timru	iocpar.timru
    #endif /* CONFIG_ISDN_TIMEOUT_RULES */
    #ifdef CONFIG_ISDN_BUDGET
    #	define	budget	iocpar.budget
    #endif /* CONFIG_ISDN_BUDGET */

    	if (minor == ISDN_MINOR_STATUS) {
    		switch (cmd) {
    			case IIOCGETDVR:
    				return (TTY_DV +
    					(NET_DV << 8) +
    					(INF_DV << 16));
    			case IIOCGETCPS:
    				if (arg) {
    					ulong *p = (ulong *) arg;
    					int i;
    					if ((ret = verify_area(VERIFY_WRITE, (void *) arg,
    							       sizeof(ulong) * ISDN_MAX_CHANNELS * 2)))
    						return ret;
    					for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    						put_user(dev->ibytes[i], p++);
    						put_user(dev->obytes[i], p++);
    					}
    					return 0;
    				} else
    					return -EINVAL;
    				break;
    			default:
    				return -EINVAL;
    		}
    	}
    	if (!dev->drivers)
    		return -ENODEV;
    	if (minor < ISDN_MINOR_CTRL) {
    		drvidx = isdn_minor2drv(minor);
    		if (drvidx < 0)
    			return -ENODEV;
    		chidx = isdn_minor2chan(minor);
    		if (!dev->drv[drvidx]->running)
    			return -ENODEV;
    		return 0;
    	}
    	if (minor <= ISDN_MINOR_CTRLMAX) {
    /*
     * isdn net devices manage lots of configuration variables as linked lists.
     * Those lists must only be manipulated from user space. Some of the ioctl's
     * service routines access user space and are not atomic. Therefor, ioctl's
     * manipulating the lists and ioctl's sleeping while accessing the lists
     * are serialized by means of a semaphore.
     */
    		switch (cmd) {
    #ifdef CONFIG_NETDEVICES
    			case IIOCNETAIF:
    				/* Add a network-interface */
    				if (arg) {
    					if (copy_from_user(name, (char *) arg, sizeof(name)))
    						return -EFAULT;
    					s = name;
    				} else {
    					s = NULL;
    				}
    				ret = down_interruptible(&dev->sem);
    				if( ret ) return ret;
    				if ((s = isdn_net_new(s, NULL))) {
    					if (copy_to_user((char *) arg, s, strlen(s) + 1)){
    						ret = -EFAULT;
    					} else {
    						ret = 0;
    					}
    				} else
    					ret = -ENODEV;
    				up(&dev->sem);
    				return ret;
    			case IIOCNETASL:
    				/* Add a slave to a network-interface */
    				if (arg) {
    					if (copy_from_user(bname, (char *) arg, sizeof(bname) - 1))
    						return -EFAULT;
    				} else
    					return -EINVAL;
    				ret = down_interruptible(&dev->sem);
    				if( ret ) return ret;
    				if ((s = isdn_net_newslave(bname))) {
    					if (copy_to_user((char *) arg, s, strlen(s) + 1)){
    						ret = -EFAULT;
    					} else {
    						ret = 0;
    					}
    				} else
    					ret = -ENODEV;
    				up(&dev->sem);
    				return ret;
    			case IIOCNETDIF:
    				/* Delete a network-interface */
    				if (arg) {
    					if (copy_from_user(name, (char *) arg, sizeof(name)))
    						return -EFAULT;
    					ret = down_interruptible(&dev->sem);
    					if( ret ) return ret;
    					ret = isdn_net_rm(name);
    					up(&dev->sem);
    					return ret;
    				} else
    					return -EINVAL;
    			case IIOCNETSCF:
    				/* Set configurable parameters of a network-interface */
    				if (arg) {
    					if (copy_from_user((char *) &cfg, (char *) arg, sizeof(cfg)))
    						return -EFAULT;
    					return isdn_net_setcfg(&cfg);
    				} else
    					return -EINVAL;
    			case IIOCNETGCF:
    				/* Get configurable parameters of a network-interface */
    				if (arg) {
    					if (copy_from_user((char *) &cfg, (char *) arg, sizeof(cfg)))
    						return -EFAULT;
    					if (!(ret = isdn_net_getcfg(&cfg))) {
    						if (copy_to_user((char *) arg, (char *) &cfg, sizeof(cfg)))
    							return -EFAULT;
    					}
    					return ret;
    				} else
    					return -EINVAL;
    			case IIOCNETANM:
    				/* Add a phone-number to a network-interface */
    				if (arg) {
    					if (copy_from_user((char *) &phone, (char *) arg, sizeof(phone)))
    						return -EFAULT;
    					ret = down_interruptible(&dev->sem);
    					if( ret ) return ret;
    					ret = isdn_net_addphone(&phone);
    					up(&dev->sem);
    					return ret;
    				} else
    					return -EINVAL;
    			case IIOCNETGNM:
    				/* Get list of phone-numbers of a network-interface */
    				if (arg) {
    					if (copy_from_user((char *) &phone, (char *) arg, sizeof(phone)))
    						return -EFAULT;
    					ret = down_interruptible(&dev->sem);
    					if( ret ) return ret;
    					ret = isdn_net_getphones(&phone, (char *) arg);
    					up(&dev->sem);
    					return ret;
    				} else
    					return -EINVAL;
    			case IIOCNETDNM:
    				/* Delete a phone-number of a network-interface */
    				if (arg) {
    					if (copy_from_user((char *) &phone, (char *) arg, sizeof(phone)))
    						return -EFAULT;
    					ret = down_interruptible(&dev->sem);
    					if( ret ) return ret;
    					ret = isdn_net_delphone(&phone);
    					up(&dev->sem);
    					return ret;
    				} else
    					return -EINVAL;
    			case IIOCNETDIL:
    				/* Force dialing of a network-interface */
    				if (arg) {
    					if (copy_from_user(name, (char *) arg, sizeof(name)))
    						return -EFAULT;
    					return isdn_net_force_dial(name);
    				} else
    					return -EINVAL;
    #ifdef CONFIG_ISDN_PPP
    			case IIOCNETALN:
    				if (!arg)
    					return -EINVAL;
    				if (copy_from_user(name, (char *) arg, sizeof(name)))
    					return -EFAULT;
    				return isdn_ppp_dial_slave(name);
    			case IIOCNETDLN:
    				if (!arg)
    					return -EINVAL;
    				if (copy_from_user(name, (char *) arg, sizeof(name)))
    					return -EFAULT;
    				return isdn_ppp_hangup_slave(name);
    #endif
    			case IIOCNETHUP:
    				/* Force hangup of a network-interface */
    				if (!arg)
    					return -EINVAL;
    				if (copy_from_user(name, (char *) arg, sizeof(name)))
    					return -EFAULT;
    				return isdn_net_force_hangup(name);
    				break;
    #ifdef CONFIG_ISDN_TIMEOUT_RULES
    			case IIOCNETARU:
    				/* Add a rule to a network-interface */
    				if (arg) {
    					if(copy_from_user((char *) &timru, (char *) arg, sizeof(timru)))
    						return -EFAULT;
    					return(isdn_timru_ioctl_add_rule(&timru));
    				} else
    					return(-EINVAL);
    			case IIOCNETDRU:
    				/* Delete a rule from a network-interface */
    				if (arg) {
    					if(copy_from_user((char *) &timru, (char *) arg, sizeof(timru)))
    						return -EFAULT;
    					return(isdn_timru_ioctl_del_rule(&timru));
    				} else
    					return(-EINVAL);
    			case IIOCNETGRU:
    				/* Get a rule of a network-interface */
    				if (arg) {
    					if(copy_from_user((char *)&timru, (char *)arg, sizeof(timru)))
    						return -EFAULT;

    					if((ret = isdn_timru_ioctl_get_rule(&timru)))
    						return(ret);

    					if(copy_to_user((char *)arg, (char *)&timru, sizeof(timru)))
    						return -EFAULT;

    					return(0);
    				} else
    					return(-EINVAL);
    #endif /* CONFIG_ISDN_TIMEOUT_RULES */

    #ifdef CONFIG_ISDN_BUDGET
    			case IIOCNETBUD:
    				/* handle budget-accounting of a network-interface */
    				if (arg) {
    					if(copy_from_user((char *)&budget, (char *)arg, sizeof(budget)))
    						return -EFAULT;

    					if((ret = isdn_budget_ioctl(&budget)))
    						return(ret);

    					if(copy_to_user((char *)arg, (char *)&budget, sizeof(budget)))
    						return -EFAULT;

    					return(0);
    				} else
    					return(-EINVAL);
    #endif /* CONFIG_ISDN_BUDGET */
    #endif                          /* CONFIG_NETDEVICES */
    			case IIOCSETVER:
    				dev->net_verbose = arg;
    				printk(KERN_INFO "isdn: Verbose-Level is %d\n", dev->net_verbose);
    				return 0;
    			case IIOCSETGST:
    				if (arg)
    					dev->global_flags |= ISDN_GLOBAL_STOPPED;
    				else
    					dev->global_flags &= ~ISDN_GLOBAL_STOPPED;
    				printk(KERN_INFO "isdn: Global Mode %s\n",
    				       (dev->global_flags & ISDN_GLOBAL_STOPPED) ? "stopped" : "running");
    				return 0;
    			case IIOCSETBRJ:
    				drvidx = -1;
    				if (arg) {
    					int i;
    					char *p;
    					if (copy_from_user((char *) &iocts, (char *) arg,
    					     sizeof(isdn_ioctl_struct)))
    						return -EFAULT;
    					if (strlen(iocts.drvid)) {
    						if ((p = strchr(iocts.drvid, ',')))
    							*p = 0;
    						drvidx = -1;
    						for (i = 0; i < ISDN_MAX_DRIVERS; i++)
    							if (!(strcmp(dev->drvid[i], iocts.drvid))) {
    								drvidx = i;
    								break;
    							}
    					}
    				}
    				if (drvidx == -1)
    					return -ENODEV;
    				dev->drv[drvidx]->reject_bus = iocts.arg;
    				return 0;
    			case IIOCSIGPRF:
    				dev->profd = current;
    				return 0;
    				break;
    			case IIOCGETPRF:
    				/* Get all Modem-Profiles */
    				if (arg) {
    					char *p = (char *) arg;
    					int i;

    					if ((ret = verify_area(VERIFY_WRITE, (void *) arg,
    					(ISDN_MODEM_ANZREG + ISDN_MSNLEN + ISDN_LMSNLEN)
    						   * ISDN_MAX_CHANNELS)))
    						return ret;

    					for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    						if (copy_to_user(p, dev->mdm.info[i].emu.profile,
    						      ISDN_MODEM_ANZREG))
    							return -EFAULT;
    						p += ISDN_MODEM_ANZREG;
    						if (copy_to_user(p, dev->mdm.info[i].emu.pmsn, ISDN_MSNLEN))
    							return -EFAULT;
    						p += ISDN_MSNLEN;
    						if (copy_to_user(p, dev->mdm.info[i].emu.plmsn, ISDN_LMSNLEN))
    							return -EFAULT;
    						p += ISDN_LMSNLEN;
    					}
    					return (ISDN_MODEM_ANZREG + ISDN_MSNLEN + ISDN_LMSNLEN) * ISDN_MAX_CHANNELS;
    				} else
    					return -EINVAL;
    				break;
    			case IIOCSETPRF:
    				/* Set all Modem-Profiles */
    				if (arg) {
    					char *p = (char *) arg;
    					int i;

    					if ((ret = verify_area(VERIFY_READ, (void *) arg,
    					(ISDN_MODEM_ANZREG + ISDN_MSNLEN)
    						   * ISDN_MAX_CHANNELS)))
    						return ret;

    					for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    						if (copy_from_user(dev->mdm.info[i].emu.profile, p,
    						     ISDN_MODEM_ANZREG))
    							return -EFAULT;
    						p += ISDN_MODEM_ANZREG;
    						if (copy_from_user(dev->mdm.info[i].emu.pmsn, p, ISDN_MSNLEN))
    							return -EFAULT;
    						p += ISDN_MSNLEN;
    					}
    					return 0;
    				} else
    					return -EINVAL;
    				break;
    			case IIOCSETMAP:
    			case IIOCGETMAP:
    				/* Set/Get MSN->EAZ-Mapping for a driver */
    				if (arg) {

    					if (copy_from_user((char *) &iocts,
    							    (char *) arg,
    					     sizeof(isdn_ioctl_struct)))
    						return -EFAULT;
    					if (strlen(iocts.drvid)) {
    						drvidx = -1;
    						for (i = 0; i < ISDN_MAX_DRIVERS; i++)
    							if (!(strcmp(dev->drvid[i], iocts.drvid))) {
    								drvidx = i;
    								break;
    							}
    					} else
    						drvidx = 0;
    					if (drvidx == -1)
    						return -ENODEV;
    					if (cmd == IIOCSETMAP) {
    						int loop = 1;

    						p = (char *) iocts.arg;
    						i = 0;
    						while (loop) {
    							int j = 0;

    							while (1) {
    								if ((ret = verify_area(VERIFY_READ, p, 1)))
    									return ret;
    								get_user(bname[j], p++);
    								switch (bname[j]) {
    									case '\0':
    										loop = 0;
    										/* Fall through */
    									case ',':
    										bname[j] = '\0';
    										strcpy(dev->drv[drvidx]->msn2eaz[i], bname);
    										j = ISDN_MSNLEN;
    										break;
    									default:
    										j++;
    								}
    								if (j >= ISDN_MSNLEN)
    									break;
    							}
    							if (++i > 9)
    								break;
    						}
    					} else {
    						p = (char *) iocts.arg;
    						for (i = 0; i < 10; i++) {
    							sprintf(bname, "%s%s",
    								strlen(dev->drv[drvidx]->msn2eaz[i]) ?
    								dev->drv[drvidx]->msn2eaz[i] : "-",
    								(i < 9) ? "," : "\0");
    							if (copy_to_user(p, bname, strlen(bname) + 1))
    								return -EFAULT;
    							p += strlen(bname);
    						}
    					}
    					return 0;
    				} else
    					return -EINVAL;
    			case IIOCDBGVAR:
    				if (arg) {
    					if (copy_to_user((char *) arg, (char *) &dev, sizeof(ulong)))
    						return -EFAULT;
    					return 0;
    				} else
    					return -EINVAL;
    				break;
    			default:
    				if ((cmd & IIOCDRVCTL) == IIOCDRVCTL)
    					cmd = ((cmd >> _IOC_NRSHIFT) & _IOC_NRMASK) & ISDN_DRVIOCTL_MASK;
    				else
    					return -EINVAL;
    				if (arg) {
    					int i;
    					char *p;
    					if (copy_from_user((char *) &iocts, (char *) arg, sizeof(isdn_ioctl_struct)))
    						return -EFAULT;
    					if (strlen(iocts.drvid)) {
    						if ((p = strchr(iocts.drvid, ',')))
    							*p = 0;
    						drvidx = -1;
    						for (i = 0; i < ISDN_MAX_DRIVERS; i++)
    							if (!(strcmp(dev->drvid[i], iocts.drvid))) {
    								drvidx = i;
    								break;
    							}
    					} else
    						drvidx = 0;
    					if (drvidx == -1)
    						return -ENODEV;
    					if ((ret = verify_area(VERIFY_WRITE, (void *) arg,
    					     sizeof(isdn_ioctl_struct))))
    						return ret;
    					c.driver = drvidx;
    					c.command = ISDN_CMD_IOCTL;
    					c.arg = cmd;
    					memcpy(c.parm.num, (char *) &iocts.arg, sizeof(ulong));
    					ret = isdn_command(&c);
    					memcpy((char *) &iocts.arg, c.parm.num, sizeof(ulong));
    					if (copy_to_user((char *) arg, &iocts, sizeof(isdn_ioctl_struct)))
    						return -EFAULT;
    					return ret;
    				} else
    					return -EINVAL;
    		}
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX)
    		return (isdn_ppp_ioctl(minor - ISDN_MINOR_PPP, file, cmd, arg));
    #endif
    	return -ENODEV;

    #undef name
    #undef bname
    #undef iocts
    #undef phone
    #undef cfg
    }

    /*
     * Open the device code.
     * MOD_INC_USE_COUNT make sure that the driver memory is not freed
     * while the device is in use.
     */
    static int
    isdn_open(struct inode *ino, struct file *filep)
    {
    	uint minor = MINOR(ino->i_rdev);
    	int drvidx;
    	int chidx;
    	isdn_ctrl c;

    	if (minor == ISDN_MINOR_STATUS) {
    		infostruct *p;

    		if ((p = (infostruct *) kmalloc(sizeof(infostruct), GFP_KERNEL))) {
    			MOD_INC_USE_COUNT;
    			p->next = (char *) dev->infochain;
    			p->private = (char *) &(filep->private_data);
    			dev->infochain = p;
    			/* At opening we allow a single update */
    			filep->private_data = (char *) 1;
    			return 0;
    		} else
    			return -ENOMEM;
    	}
    	if (!dev->channels)
    		return -ENODEV;
    	if (minor < ISDN_MINOR_CTRL) {
    		drvidx = isdn_minor2drv(minor);
    		if (drvidx < 0)
    			return -ENODEV;
    		chidx = isdn_minor2chan(minor);
    		if (!dev->drv[drvidx]->running)
    			return -ENODEV;
    		if (!(dev->drv[drvidx]->flags & (1 << chidx)))
    			return -ENODEV;
    		c.command = ISDN_CMD_LOCK;
    		c.driver = drvidx;
    		isdn_command(&c);
    		MOD_INC_USE_COUNT;
    		return 0;
    	}
    	if (minor <= ISDN_MINOR_CTRLMAX) {
    		drvidx = isdn_minor2drv(minor - ISDN_MINOR_CTRL);
    		if (drvidx < 0)
    			return -ENODEV;
    		c.command = ISDN_CMD_LOCK;
    		c.driver = drvidx;
    		MOD_INC_USE_COUNT;
    		isdn_command(&c);
    		return 0;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX) {
    		int ret;
    		if (!(ret = isdn_ppp_open(minor - ISDN_MINOR_PPP, filep)))
    			MOD_INC_USE_COUNT;
    		return ret;
    	}
    #endif
    	return -ENODEV;
    }

    static int
    isdn_close(struct inode *ino, struct file *filep)
    {
    	uint minor = MINOR(ino->i_rdev);
    	int drvidx;
    	isdn_ctrl c;

    	MOD_DEC_USE_COUNT;
    	if (minor == ISDN_MINOR_STATUS) {
    		infostruct *p = dev->infochain;
    		infostruct *q = NULL;
    		while (p) {
    			if (p->private == (char *) &(filep->private_data)) {
    				if (q)
    					q->next = p->next;
    				else
    					dev->infochain = (infostruct *) (p->next);
    				kfree(p);
    				return 0;
    			}
    			q = p;
    			p = (infostruct *) (p->next);
    		}
    		printk(KERN_WARNING "isdn: No private data while closing isdnctrl\n");
    		return 0;
    	}
    	if (minor < ISDN_MINOR_CTRL) {
    		drvidx = isdn_minor2drv(minor);
    		if (drvidx < 0)
    			return 0;
    		c.command = ISDN_CMD_UNLOCK;
    		c.driver = drvidx;
    		isdn_command(&c);
    		return 0;
    	}
    	if (minor <= ISDN_MINOR_CTRLMAX) {
    		drvidx = isdn_minor2drv(minor - ISDN_MINOR_CTRL);
    		if (drvidx < 0)
    			return 0;
    		if (dev->profd == current)
    			dev->profd = NULL;
    		c.command = ISDN_CMD_UNLOCK;
    		c.driver = drvidx;
    		isdn_command(&c);
    		return 0;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (minor <= ISDN_MINOR_PPPMAX)
    		isdn_ppp_release(minor - ISDN_MINOR_PPP, filep);
    #endif
    	return 0;
    }

    static struct file_operations isdn_fops =
    {
    	isdn_lseek,
    	isdn_read,
    	isdn_write,
    	NULL,                   /* isdn_readdir */
    	isdn_poll,              /* isdn_poll */
    	isdn_ioctl,             /* isdn_ioctl */
    	NULL,                   /* isdn_mmap */
    	isdn_open,
    	isdn_close,
    	NULL                    /* fsync */
    };

    char *
    isdn_map_eaz2msn(char *msn, int di)
    {
    	driver *this = dev->drv[di];
    	int i;

    	if (strlen(msn) == 1) {
    		i = msn[0] - '0';
    		if ((i >= 0) && (i <= 9))
    			if (strlen(this->msn2eaz[i]))
    				return (this->msn2eaz[i]);
    	}
    	return (msn);
    }

    /*
     * Find an unused ISDN-channel, whose feature-flags match the
     * given L2- and L3-protocols.
     */
    #define L2V (~(ISDN_FEATURE_L2_V11096|ISDN_FEATURE_L2_V11019|ISDN_FEATURE_L2_V11038))

    int
    isdn_get_free_channel(int usage, int l2_proto, int l3_proto, int pre_dev
    		      ,int pre_chan)
    {
    	int i;
    	ulong flags;
    	ulong features;
    	ulong vfeatures;
    	isdn_ctrl cmd;

    	save_flags(flags);
    	cli();
    	features = ((1 << l2_proto) | (0x10000 << l3_proto));
    	vfeatures = (((1 << l2_proto) | (0x10000 << l3_proto)) &
    		     ~(ISDN_FEATURE_L2_V11096|ISDN_FEATURE_L2_V11019|ISDN_FEATURE_L2_V11038));
    	/* If Layer-2 protocol is V.110, accept drivers with
    	 * transparent feature even if these don't support V.110
    	 * because we can emulate this in linklevel.
    	 */
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    		if (USG_NONE(dev->usage[i]) &&
    		    (dev->drvmap[i] != -1)) {
    			int d = dev->drvmap[i];
    			if ((dev->usage[i] & ISDN_USAGE_EXCLUSIVE) &&
    			((pre_dev != d) || (pre_chan != dev->chanmap[i])))
    				continue;
    			if ((dev->drv[d]->running)) {
    				if (((dev->drv[d]->interface->features & features) == features) ||
    				    (((dev->drv[d]->interface->features & vfeatures) == vfeatures) &&
    				     (dev->drv[d]->interface->features & ISDN_FEATURE_L2_TRANS))) {
    					if ((pre_dev < 0) || (pre_chan < 0)) {
    						dev->usage[i] &= ISDN_USAGE_EXCLUSIVE;
    						dev->usage[i] |= usage;
    						isdn_info_update();
    						cmd.driver = d;
    						cmd.arg = 0;
    						cmd.command = ISDN_CMD_LOCK;
    						isdn_command(&cmd);
    						restore_flags(flags);
    						return i;
    					} else {
    						if ((pre_dev == d) && (pre_chan == dev->chanmap[i])) {
    							dev->usage[i] &= ISDN_USAGE_EXCLUSIVE;
    							dev->usage[i] |= usage;
    							isdn_info_update();
    							cmd.driver = d;
    							cmd.arg = 0;
    							cmd.command = ISDN_CMD_LOCK;
    							isdn_command(&cmd);
    							restore_flags(flags);
    							return i;
    						}
    					}
    				}
    			}
    		}
    	restore_flags(flags);
    	return -1;
    }

    /*
     * Set state of ISDN-channel to 'unused'
     */
    void
    isdn_free_channel(int di, int ch, int usage)
    {
    	int i;
    	ulong flags;
    	isdn_ctrl cmd;

    	save_flags(flags);
    	cli();
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    		if (((dev->usage[i] & ISDN_USAGE_MASK) == usage) &&
    		    (dev->drvmap[i] == di) &&
    		    (dev->chanmap[i] == ch)) {
    			dev->usage[i] &= (ISDN_USAGE_NONE | ISDN_USAGE_EXCLUSIVE);
    			strcpy(dev->num[i], "???");
    			dev->ibytes[i] = 0;
    			dev->obytes[i] = 0;
    			isdn_info_update();
    			isdn_free_queue(&dev->drv[di]->rpqueue[ch]);
    			cmd.driver = di;
    			cmd.arg = ch;
    			cmd.command = ISDN_CMD_UNLOCK;
    			restore_flags(flags);
    			isdn_command(&cmd);
    			return;
    		}
    	restore_flags(flags);
    }

    /*
     * Cancel Exclusive-Flag for ISDN-channel
     */
    void
    isdn_unexclusive_channel(int di, int ch)
    {
    	int i;
    	ulong flags;

    	save_flags(flags);
    	cli();
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    		if ((dev->drvmap[i] == di) &&
    		    (dev->chanmap[i] == ch)) {
    			dev->usage[i] &= ~ISDN_USAGE_EXCLUSIVE;
    			isdn_info_update();
    			restore_flags(flags);
    			return;
    		}
    	restore_flags(flags);
    }

    /*
     *  writebuf replacement for SKB_ABLE drivers
     */
    static int
    isdn_writebuf_stub(int drvidx, int chan, const u_char * buf, int len,
    		   int user)
    {
    	int ret;
    	int hl = dev->drv[drvidx]->interface->hl_hdrlen;
    	struct sk_buff *skb = alloc_skb(hl + len, GFP_ATOMIC);

    	if (!skb)
    		return 0;
    	skb_reserve(skb, hl);
    	if (user)
    		copy_from_user(skb_put(skb, len), buf, len);
    	else
    		memcpy(skb_put(skb, len), buf, len);
    	ret = dev->drv[drvidx]->interface->writebuf_skb(drvidx, chan, 1, skb);
    	if (ret <= 0)
    		dev_kfree_skb(skb);
    	if (ret > 0)
    		dev->obytes[isdn_dc2minor(drvidx, chan)] += ret;
    	return ret;
    }

    /*
     * Return: length of data on success, -ERRcode on failure.
     */
    int
    isdn_writebuf_skb_stub(int drvidx, int chan, int ack, struct sk_buff *skb)
    {
    	int ret;
    	struct sk_buff *nskb = NULL;
    	int v110_ret = skb->len;
    	int idx = isdn_dc2minor(drvidx, chan);

    	if (dev->v110[idx]) {
    		atomic_inc(&dev->v110use[idx]);
    		nskb = isdn_v110_encode(dev->v110[idx], skb);
    		atomic_dec(&dev->v110use[idx]);
    		if (!nskb)
    			return 0;
    		v110_ret = *((int *)nskb->data);
    		skb_pull(nskb, sizeof(int));
    		if (!nskb->len) {
    			dev_kfree_skb(nskb);
    			dev_kfree_skb(skb);
    			return v110_ret;
    		}
    		/* V.110 must always be acknowledged */
    		ack = 1;
    		ret = dev->drv[drvidx]->interface->writebuf_skb(drvidx, chan, ack, nskb);
    	} else
    		ret = dev->drv[drvidx]->interface->writebuf_skb(drvidx, chan, ack, skb);
    	if (ret > 0) {
    		dev->obytes[idx] += ret;
    		if (dev->v110[idx]) {
    			atomic_inc(&dev->v110use[idx]);
    			dev->v110[idx]->skbuser++;
    			atomic_dec(&dev->v110use[idx]);
    			dev_kfree_skb(skb);
    			/* For V.110 return unencoded data length */
    			ret = v110_ret;
    			if (ret == skb->len)
    				dev_kfree_skb(skb);
    		}
    	} else
    		if (dev->v110[idx])
    			dev_kfree_skb(nskb);
    	return ret;
    }

    int
    register_isdn_module(isdn_module *m) {
    #if 0
    	isdn_module_list **pp = &dev->modules;
    	isdn_module *new = kmalloc(sizeof(isdn_module_list), GFP_KERNEL);

    	if (!new) {
    		printk(KERN_WARNING "isdn: Out of memory in register_isdn_module\n");
    		return -1;
    	}
    	while (*pp && (*pp)->orig != m)
    		pp = &(*pp)->next;
    	if (*pp != NULL) {
    		printk(KERN_WARNING "isdn: Module %s already registered\n", m->name);
    		return -1;
    	}
    	while (*pp && ((*pp)->module.priority < m->priority))
    		pp = &(*pp)->next;
    	new->next = *pp;
    	new->orig = m;
    	new->module = *m;

    	*pp = new;
    #endif
    	return 0;
    }

    int
    unregister_isdn_module(isdn_module *m) {
    #if 0
    	isdn_module_list **pp = &dev->modules;

    	while (*pp && *pp != m)
    		pp = &(*pp)->next;
    	if (*pp == NULL) {
    		printk(KERN_WARNING "isdn: Module %s not found\n", m->name);
    		return -1;
    	}
    #endif
    	return 0;
    }

    /*
     * Low-level-driver registration
     */

    EXPORT_SYMBOL(register_isdn);
    EXPORT_SYMBOL(register_isdn_module);
    EXPORT_SYMBOL(unregister_isdn_module);
    #ifdef CONFIG_ISDN_PPP
    EXPORT_SYMBOL(isdn_ppp_register_compressor);
    EXPORT_SYMBOL(isdn_ppp_unregister_compressor);
    #endif

    int
    register_isdn(isdn_if * i)
    {
    	driver *d;
    	int n,
    	 j,
    	 k;
    	ulong flags;
    	int drvidx;

    	if (dev->drivers >= ISDN_MAX_DRIVERS) {
    		printk(KERN_WARNING "register_isdn: Max. %d drivers supported\n",
    		       ISDN_MAX_DRIVERS);
    		return 0;
    	}
    	n = i->channels;
    	if (dev->channels + n > ISDN_MAX_CHANNELS) {
    		printk(KERN_WARNING "register_isdn: Max. %d channels supported\n",
    		       ISDN_MAX_CHANNELS);
    		return 0;
    	}
    	if (!i->writebuf_skb) {
    		printk(KERN_WARNING "register_isdn: No write routine given.\n");
    		return 0;
    	}
    	if (!(d = (driver *) kmalloc(sizeof(driver), GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc driver-struct\n");
    		return 0;
    	}
    	memset((char *) d, 0, sizeof(driver));
    	if (!(d->rcverr = (int *) kmalloc(sizeof(int) * n, GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc rcverr\n");
    		kfree(d);
    		return 0;
    	}
    	memset((char *) d->rcverr, 0, sizeof(int) * n);
    	if (!(d->rcvcount = (int *) kmalloc(sizeof(int) * n, GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc rcvcount\n");
    		kfree(d->rcverr);
    		kfree(d);
    		return 0;
    	}
    	memset((char *) d->rcvcount, 0, sizeof(int) * n);
    	if (!(d->rpqueue =
    	      (struct sk_buff_head *) kmalloc(sizeof(struct sk_buff_head) * n, GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc rpqueue\n");
    		kfree(d->rcvcount);
    		kfree(d->rcverr);
    		kfree(d);
    		return 0;
    	}
    	for (j = 0; j < n; j++) {
    		skb_queue_head_init(&d->rpqueue[j]);
    	}
    	if (!(d->rcv_waitq = (struct wait_queue **)
    	      kmalloc(sizeof(struct wait_queue *) * n, GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc rcv_waitq\n");
    		kfree(d->rpqueue);
    		kfree(d->rcvcount);
    		kfree(d->rcverr);
    		kfree(d);
    		return 0;
    	}
    	memset((char *) d->rcv_waitq, 0, sizeof(struct wait_queue *) * n);
    	if (!(d->snd_waitq = (struct wait_queue **)
    	      kmalloc(sizeof(struct wait_queue *) * n, GFP_KERNEL))) {
    		printk(KERN_WARNING "register_isdn: Could not alloc snd_waitq\n");
    		kfree(d->rcv_waitq);
    		kfree(d->rpqueue);
    		kfree(d->rcvcount);
    		kfree(d->rcverr);
    		kfree(d);
    		return 0;
    	}
    	memset((char *) d->snd_waitq, 0, sizeof(struct wait_queue *) * n);
    	d->channels = n;
    	d->loaded = 1;
    	d->maxbufsize = i->maxbufsize;
    	d->pktcount = 0;
    	d->stavail = 0;
    	d->running = 0;
    	d->flags = 0;
    	d->interface = i;
    	for (drvidx = 0; drvidx < ISDN_MAX_DRIVERS; drvidx++)
    		if (!dev->drv[drvidx])
    			break;
    	i->channels = drvidx;

    	i->rcvcallb_skb = isdn_receive_skb_callback;
    	i->statcallb = isdn_status_callback;
    	if (!strlen(i->id))
    		sprintf(i->id, "line%d", drvidx);
    	save_flags(flags);
    	cli();
    	for (j = 0; j < drvidx; j++)
    		if (!strcmp(i->id, dev->drvid[j]))
    			sprintf(i->id, "line%d", drvidx);
    	for (j = 0; j < n; j++)
    		for (k = 0; k < ISDN_MAX_CHANNELS; k++)
    			if (dev->chanmap[k] < 0) {
    				dev->chanmap[k] = j;
    				dev->drvmap[k] = drvidx;
    				break;
    			}
    	dev->drv[drvidx] = d;
    	dev->channels += n;
    	strcpy(dev->drvid[drvidx], i->id);
    	isdn_info_update();
    	dev->drivers++;
    	restore_flags(flags);
    	return 1;
    }

    /*
     *****************************************************************************
     * And now the modules code.
     *****************************************************************************
     */

    extern int printk(const char *fmt,...);

    #ifdef MODULE
    #define isdn_init init_module
    #endif

    static char *
    isdn_getrev(const char *revision)
    {
    	char *rev;
    	char *p;

    	if ((p = strchr(revision, ':'))) {
    		rev = p + 2;
    		p = strchr(rev, '$');
    		*--p = 0;
    	} else
    		rev = "???";
    	return rev;
    }

    /*
     * Allocate and initialize all data, register modem-devices
     */
    int
    isdn_init(void)
    {
    	int i;
    	char tmprev[50];

    	sti();
    	if (!(dev = (isdn_dev *) kmalloc(sizeof(isdn_dev), GFP_KERNEL))) {
    		printk(KERN_WARNING "isdn: Could not allocate device-struct.\n");
    		return -EIO;
    	}
    	memset((char *) dev, 0, sizeof(isdn_dev));
    	init_timer(&dev->timer);
    	dev->timer.function = isdn_timer_funct;
    	dev->sem = MUTEX;
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		dev->drvmap[i] = -1;
    		dev->chanmap[i] = -1;
    		dev->m_idx[i] = -1;
    		strcpy(dev->num[i], "???");
    	}
    	if (register_chrdev(ISDN_MAJOR, "isdn", &isdn_fops)) {
    		printk(KERN_WARNING "isdn: Could not register control devices\n");
    		kfree(dev);
    		return -EIO;
    	}
    	if ((i = isdn_tty_modem_init()) < 0) {
    		printk(KERN_WARNING "isdn: Could not register tty devices\n");
    		if (i == -3)
    			tty_unregister_driver(&dev->mdm.cua_modem);
    		if (i <= -2)
    			tty_unregister_driver(&dev->mdm.tty_modem);
    		kfree(dev);
    		unregister_chrdev(ISDN_MAJOR, "isdn");
    		return -EIO;
    	}
    #ifdef CONFIG_ISDN_PPP
    	if (isdn_ppp_init() < 0) {
    		printk(KERN_WARNING "isdn: Could not create PPP-device-structs\n");
    		tty_unregister_driver(&dev->mdm.tty_modem);
    		tty_unregister_driver(&dev->mdm.cua_modem);
    		for (i = 0; i < ISDN_MAX_CHANNELS; i++)
    			kfree(dev->mdm.info[i].xmit_buf - 4);
    		unregister_chrdev(ISDN_MAJOR, "isdn");
    		kfree(dev);
    		return -EIO;
    	}
    #endif                          /* CONFIG_ISDN_PPP */

    	strcpy(tmprev, isdn_revision);
    	printk(KERN_NOTICE "ISDN subsystem Rev: %s/", isdn_getrev(tmprev));
    	strcpy(tmprev, isdn_tty_revision);
    	printk("%s/", isdn_getrev(tmprev));
    	strcpy(tmprev, isdn_net_revision);
    	printk("%s/", isdn_getrev(tmprev));
    	strcpy(tmprev, isdn_ppp_revision);
    	printk("%s/", isdn_getrev(tmprev));
    	strcpy(tmprev, isdn_audio_revision);
    	printk("%s/", isdn_getrev(tmprev));
    	strcpy(tmprev, isdn_v110_revision);
    	printk("%s", isdn_getrev(tmprev));

    #ifdef MODULE
    	printk(" loaded\n");
    #else
    	printk("\n");
    	isdn_cards_init();
    #endif
    	isdn_info_update();
    	return 0;
    }

    #ifdef MODULE
    /*
     * Unload module
     */
    void
    cleanup_module(void)
    {
    	int flags;
    	int i;

    #ifdef CONFIG_ISDN_PPP
    	isdn_ppp_cleanup();
    #endif
    	save_flags(flags);
    	cli();
    	if (isdn_net_rmall() < 0) {
    		printk(KERN_WARNING "isdn: net-device busy, remove cancelled\n");
    		restore_flags(flags);
    		return;
    	}
    	if (tty_unregister_driver(&dev->mdm.tty_modem)) {
    		printk(KERN_WARNING "isdn: ttyI-device busy, remove cancelled\n");
    		restore_flags(flags);
    		return;
    	}
    	if (tty_unregister_driver(&dev->mdm.cua_modem)) {
    		printk(KERN_WARNING "isdn: cui-device busy, remove cancelled\n");
    		restore_flags(flags);
    		return;
    	}
    	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
    		isdn_tty_cleanup_xmit(&dev->mdm.info[i]);
    		kfree(dev->mdm.info[i].xmit_buf - 4);
    	}
    	if (unregister_chrdev(ISDN_MAJOR, "isdn") != 0) {
    		printk(KERN_WARNING "isdn: controldevice busy, remove cancelled\n");
    	} else {
    		del_timer(&dev->timer);
    		kfree(dev);
    		printk(KERN_NOTICE "ISDN-subsystem unloaded\n");
    	}
    	restore_flags(flags);
    }
    #endif