Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3198 insertions, 0 deletions

diff --git a/drivers/isdn/i4l/isdn_net.c b/drivers/isdn/i4l/isdn_net.c
new file mode 100644
index 000000000..c138f66f2
--- /dev/null
+++ b/drivers/isdn/i4l/isdn_net.c
@@ -0,0 +1,3198 @@
+/* $Id: isdn_net.c,v 1.1.2.2 2004/01/12 22:37:19 keil Exp $
+ *
+ * Linux ISDN subsystem, network interfaces and related functions (linklevel).
+ *
+ * Copyright 1994-1998  by Fritz Elfert (fritz@isdn4linux.de)
+ * Copyright 1995,96    by Thinking Objects Software GmbH Wuerzburg
+ * Copyright 1995,96    by Michael Hipp (Michael.Hipp@student.uni-tuebingen.de)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ * Data Over Voice (DOV) support added - Guy Ellis 23-Mar-02
+ *                                       guy@traverse.com.au
+ * Outgoing calls - looks for a 'V' in first char of dialed number
+ * Incoming calls - checks first character of eaz as follows:
+ *   Numeric - accept DATA only - original functionality
+ *   'V'     - accept VOICE (DOV) only
+ *   'B'     - accept BOTH DATA and DOV types
+ *
+ * Jan 2001: fix CISCO HDLC      Bjoern A. Zeeb <i4l@zabbadoz.net>
+ *           for info on the protocol, see
+ *           http://i4l.zabbadoz.net/i4l/cisco-hdlc.txt
+ */
+
+#include <linux/isdn.h>
+#include <linux/slab.h>
+#include <net/arp.h>
+#include <net/dst.h>
+#include <net/pkt_sched.h>
+#include <linux/inetdevice.h>
+#include "isdn_common.h"
+#include "isdn_net.h"
+#ifdef CONFIG_ISDN_PPP
+#include "isdn_ppp.h"
+#endif
+#ifdef CONFIG_ISDN_X25
+#include <linux/concap.h>
+#include "isdn_concap.h"
+#endif
+
+
+/*
+ * Outline of new tbusy handling:
+ *
+ * Old method, roughly spoken, consisted of setting tbusy when entering
+ * isdn_net_start_xmit() and at several other locations and clearing
+ * it from isdn_net_start_xmit() thread when sending was successful.
+ *
+ * With 2.3.x multithreaded network core, to prevent problems, tbusy should
+ * only be set by the isdn_net_start_xmit() thread and only when a tx-busy
+ * condition is detected. Other threads (in particular isdn_net_stat_callb())
+ * are only allowed to clear tbusy.
+ *
+ * -HE
+ */
+
+/*
+ * About SOFTNET:
+ * Most of the changes were pretty obvious and basically done by HE already.
+ *
+ * One problem of the isdn net device code is that it uses struct net_device
+ * for masters and slaves. However, only master interface are registered to
+ * the network layer, and therefore, it only makes sense to call netif_*
+ * functions on them.
+ *
+ * --KG
+ */
+
+/*
+ * Find out if the netdevice has been ifup-ed yet.
+ * For slaves, look at the corresponding master.
+ */
+static __inline__ int isdn_net_device_started(isdn_net_dev *n)
+{
+	isdn_net_local *lp = n->local;
+	struct net_device *dev;
+
+	if (lp->master)
+		dev = lp->master;
+	else
+		dev = n->dev;
+	return netif_running(dev);
+}
+
+/*
+ * wake up the network -> net_device queue.
+ * For slaves, wake the corresponding master interface.
+ */
+static __inline__ void isdn_net_device_wake_queue(isdn_net_local *lp)
+{
+	if (lp->master)
+		netif_wake_queue(lp->master);
+	else
+		netif_wake_queue(lp->netdev->dev);
+}
+
+/*
+ * stop the network -> net_device queue.
+ * For slaves, stop the corresponding master interface.
+ */
+static __inline__ void isdn_net_device_stop_queue(isdn_net_local *lp)
+{
+	if (lp->master)
+		netif_stop_queue(lp->master);
+	else
+		netif_stop_queue(lp->netdev->dev);
+}
+
+/*
+ * find out if the net_device which this lp belongs to (lp can be
+ * master or slave) is busy. It's busy iff all (master and slave)
+ * queues are busy
+ */
+static __inline__ int isdn_net_device_busy(isdn_net_local *lp)
+{
+	isdn_net_local *nlp;
+	isdn_net_dev *nd;
+	unsigned long flags;
+
+	if (!isdn_net_lp_busy(lp))
+		return 0;
+
+	if (lp->master)
+		nd = ISDN_MASTER_PRIV(lp)->netdev;
+	else
+		nd = lp->netdev;
+
+	spin_lock_irqsave(&nd->queue_lock, flags);
+	nlp = lp->next;
+	while (nlp != lp) {
+		if (!isdn_net_lp_busy(nlp)) {
+			spin_unlock_irqrestore(&nd->queue_lock, flags);
+			return 0;
+		}
+		nlp = nlp->next;
+	}
+	spin_unlock_irqrestore(&nd->queue_lock, flags);
+	return 1;
+}
+
+static __inline__ void isdn_net_inc_frame_cnt(isdn_net_local *lp)
+{
+	atomic_inc(&lp->frame_cnt);
+	if (isdn_net_device_busy(lp))
+		isdn_net_device_stop_queue(lp);
+}
+
+static __inline__ void isdn_net_dec_frame_cnt(isdn_net_local *lp)
+{
+	atomic_dec(&lp->frame_cnt);
+
+	if (!(isdn_net_device_busy(lp))) {
+		if (!skb_queue_empty(&lp->super_tx_queue)) {
+			schedule_work(&lp->tqueue);
+		} else {
+			isdn_net_device_wake_queue(lp);
+		}
+	}
+}
+
+static __inline__ void isdn_net_zero_frame_cnt(isdn_net_local *lp)
+{
+	atomic_set(&lp->frame_cnt, 0);
+}
+
+/* For 2.2.x we leave the transmitter busy timeout at 2 secs, just
+ * to be safe.
+ * For 2.3.x we push it up to 20 secs, because call establishment
+ * (in particular callback) may take such a long time, and we
+ * don't want confusing messages in the log. However, there is a slight
+ * possibility that this large timeout will break other things like MPPP,
+ * which might rely on the tx timeout. If so, we'll find out this way...
+ */
+
+#define ISDN_NET_TX_TIMEOUT (20 * HZ)
+
+/* Prototypes */
+
+static int isdn_net_force_dial_lp(isdn_net_local *);
+static netdev_tx_t isdn_net_start_xmit(struct sk_buff *,
+				       struct net_device *);
+
+static void isdn_net_ciscohdlck_connected(isdn_net_local *lp);
+static void isdn_net_ciscohdlck_disconnected(isdn_net_local *lp);
+
+char *isdn_net_revision = "$Revision: 1.1.2.2 $";
+
+/*
+ * Code for raw-networking over ISDN
+ */
+
+static void
+isdn_net_unreachable(struct net_device *dev, struct sk_buff *skb, char *reason)
+{
+	if (skb) {
+
+		u_short proto = ntohs(skb->protocol);
+
+		printk(KERN_DEBUG "isdn_net: %s: %s, signalling dst_link_failure %s\n",
+		       dev->name,
+		       (reason != NULL) ? reason : "unknown",
+		       (proto != ETH_P_IP) ? "Protocol != ETH_P_IP" : "");
+
+		dst_link_failure(skb);
+	}
+	else {  /* dial not triggered by rawIP packet */
+		printk(KERN_DEBUG "isdn_net: %s: %s\n",
+		       dev->name,
+		       (reason != NULL) ? reason : "reason unknown");
+	}
+}
+
+static void
+isdn_net_reset(struct net_device *dev)
+{
+#ifdef CONFIG_ISDN_X25
+	struct concap_device_ops *dops =
+		((isdn_net_local *)netdev_priv(dev))->dops;
+	struct concap_proto *cprot =
+		((isdn_net_local *)netdev_priv(dev))->netdev->cprot;
+#endif
+#ifdef CONFIG_ISDN_X25
+	if (cprot && cprot->pops && dops)
+		cprot->pops->restart(cprot, dev, dops);
+#endif
+}
+
+/* Open/initialize the board. */
+static int
+isdn_net_open(struct net_device *dev)
+{
+	int i;
+	struct net_device *p;
+	struct in_device *in_dev;
+
+	/* moved here from isdn_net_reset, because only the master has an
+	   interface associated which is supposed to be started. BTW:
+	   we need to call netif_start_queue, not netif_wake_queue here */
+	netif_start_queue(dev);
+
+	isdn_net_reset(dev);
+	/* Fill in the MAC-level header (not needed, but for compatibility... */
+	for (i = 0; i < ETH_ALEN - sizeof(u32); i++)
+		dev->dev_addr[i] = 0xfc;
+	if ((in_dev = dev->ip_ptr) != NULL) {
+		/*
+		 *      Any address will do - we take the first
+		 */
+		struct in_ifaddr *ifa = in_dev->ifa_list;
+		if (ifa != NULL)
+			memcpy(dev->dev_addr + 2, &ifa->ifa_local, 4);
+	}
+
+	/* If this interface has slaves, start them also */
+	p = MASTER_TO_SLAVE(dev);
+	if (p) {
+		while (p) {
+			isdn_net_reset(p);
+			p = MASTER_TO_SLAVE(p);
+		}
+	}
+	isdn_lock_drivers();
+	return 0;
+}
+
+/*
+ * Assign an ISDN-channel to a net-interface
+ */
+static void
+isdn_net_bind_channel(isdn_net_local *lp, int idx)
+{
+	lp->flags |= ISDN_NET_CONNECTED;
+	lp->isdn_device = dev->drvmap[idx];
+	lp->isdn_channel = dev->chanmap[idx];
+	dev->rx_netdev[idx] = lp->netdev;
+	dev->st_netdev[idx] = lp->netdev;
+}
+
+/*
+ * unbind a net-interface (resets interface after an error)
+ */
+static void
+isdn_net_unbind_channel(isdn_net_local *lp)
+{
+	skb_queue_purge(&lp->super_tx_queue);
+
+	if (!lp->master) {	/* reset only master device */
+		/* Moral equivalent of dev_purge_queues():
+		   BEWARE! This chunk of code cannot be called from hardware
+		   interrupt handler. I hope it is true. --ANK
+		*/
+		qdisc_reset_all_tx(lp->netdev->dev);
+	}
+	lp->dialstate = 0;
+	dev->rx_netdev[isdn_dc2minor(lp->isdn_device, lp->isdn_channel)] = NULL;
+	dev->st_netdev[isdn_dc2minor(lp->isdn_device, lp->isdn_channel)] = NULL;
+	if (lp->isdn_device != -1 && lp->isdn_channel != -1)
+		isdn_free_channel(lp->isdn_device, lp->isdn_channel,
+				  ISDN_USAGE_NET);
+	lp->flags &= ~ISDN_NET_CONNECTED;
+	lp->isdn_device = -1;
+	lp->isdn_channel = -1;
+}
+
+/*
+ * Perform auto-hangup and cps-calculation for net-interfaces.
+ *
+ * auto-hangup:
+ * Increment idle-counter (this counter is reset on any incoming or
+ * outgoing packet), if counter exceeds configured limit either do a
+ * hangup immediately or - if configured - wait until just before the next
+ * charge-info.
+ *
+ * cps-calculation (needed for dynamic channel-bundling):
+ * Since this function is called every second, simply reset the
+ * byte-counter of the interface after copying it to the cps-variable.
+ */
+static unsigned long last_jiffies = -HZ;
+
+void
+isdn_net_autohup(void)
+{
+	isdn_net_dev *p = dev->netdev;
+	int anymore;
+
+	anymore = 0;
+	while (p) {
+		isdn_net_local *l = p->local;
+		if (jiffies == last_jiffies)
+			l->cps = l->transcount;
+		else
+			l->cps = (l->transcount * HZ) / (jiffies - last_jiffies);
+		l->transcount = 0;
+		if (dev->net_verbose > 3)
+			printk(KERN_DEBUG "%s: %d bogocps\n", p->dev->name, l->cps);
+		if ((l->flags & ISDN_NET_CONNECTED) && (!l->dialstate)) {
+			anymore = 1;
+			l->huptimer++;
+			/*
+			 * if there is some dialmode where timeout-hangup
+			 * should _not_ be done, check for that here
+			 */
+			if ((l->onhtime) &&
+			    (l->huptimer > l->onhtime))
+			{
+				if (l->hupflags & ISDN_MANCHARGE &&
+				    l->hupflags & ISDN_CHARGEHUP) {
+					while (time_after(jiffies, l->chargetime + l->chargeint))
+						l->chargetime += l->chargeint;
+					if (time_after(jiffies, l->chargetime + l->chargeint - 2 * HZ))
+						if (l->outgoing || l->hupflags & ISDN_INHUP)
+							isdn_net_hangup(p->dev);
+				} else if (l->outgoing) {
+					if (l->hupflags & ISDN_CHARGEHUP) {
+						if (l->hupflags & ISDN_WAITCHARGE) {
+							printk(KERN_DEBUG "isdn_net: Hupflags of %s are %X\n",
+							       p->dev->name, l->hupflags);
+							isdn_net_hangup(p->dev);
+						} else if (time_after(jiffies, l->chargetime + l->chargeint)) {
+							printk(KERN_DEBUG
+							       "isdn_net: %s: chtime = %lu, chint = %d\n",
+							       p->dev->name, l->chargetime, l->chargeint);
+							isdn_net_hangup(p->dev);
+						}
+					} else
+						isdn_net_hangup(p->dev);
+				} else if (l->hupflags & ISDN_INHUP)
+					isdn_net_hangup(p->dev);
+			}
+
+			if (dev->global_flags & ISDN_GLOBAL_STOPPED || (ISDN_NET_DIALMODE(*l) == ISDN_NET_DM_OFF)) {
+				isdn_net_hangup(p->dev);
+				break;
+			}
+		}
+		p = (isdn_net_dev *) p->next;
+	}
+	last_jiffies = jiffies;
+	isdn_timer_ctrl(ISDN_TIMER_NETHANGUP, anymore);
+}
+
+static void isdn_net_lp_disconnected(isdn_net_local *lp)
+{
+	isdn_net_rm_from_bundle(lp);
+}
+
+/*
+ * Handle status-messages from ISDN-interfacecard.
+ * This function is called from within the main-status-dispatcher
+ * isdn_status_callback, which itself is called from the low-level driver.
+ * Return: 1 = Event handled, 0 = not for us or unknown Event.
+ */
+int
+isdn_net_stat_callback(int idx, isdn_ctrl *c)
+{
+	isdn_net_dev *p = dev->st_netdev[idx];
+	int cmd = c->command;
+
+	if (p) {
+		isdn_net_local *lp = p->local;
+#ifdef CONFIG_ISDN_X25
+		struct concap_proto *cprot = lp->netdev->cprot;
+		struct concap_proto_ops *pops = cprot ? cprot->pops : NULL;
+#endif
+		switch (cmd) {
+		case ISDN_STAT_BSENT:
+			/* A packet has successfully been sent out */
+			if ((lp->flags & ISDN_NET_CONNECTED) &&
+			    (!lp->dialstate)) {
+				isdn_net_dec_frame_cnt(lp);
+				lp->stats.tx_packets++;
+				lp->stats.tx_bytes += c->parm.length;
+			}
+			return 1;
+		case ISDN_STAT_DCONN:
+			/* D-Channel is up */
+			switch (lp->dialstate) {
+			case 4:
+			case 7:
+			case 8:
+				lp->dialstate++;
+				return 1;
+			case 12:
+				lp->dialstate = 5;
+				return 1;
+			}
+			break;
+		case ISDN_STAT_DHUP:
+			/* Either D-Channel-hangup or error during dialout */
+#ifdef CONFIG_ISDN_X25
+			/* If we are not connencted then dialing had
+			   failed. If there are generic encap protocol
+			   receiver routines signal the closure of
+			   the link*/
+
+			if (!(lp->flags & ISDN_NET_CONNECTED)
+			    && pops && pops->disconn_ind)
+				pops->disconn_ind(cprot);
+#endif /* CONFIG_ISDN_X25 */
+			if ((!lp->dialstate) && (lp->flags & ISDN_NET_CONNECTED)) {
+				if (lp->p_encap == ISDN_NET_ENCAP_CISCOHDLCK)
+					isdn_net_ciscohdlck_disconnected(lp);
+#ifdef CONFIG_ISDN_PPP
+				if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+					isdn_ppp_free(lp);
+#endif
+				isdn_net_lp_disconnected(lp);
+				isdn_all_eaz(lp->isdn_device, lp->isdn_channel);
+				printk(KERN_INFO "%s: remote hangup\n", p->dev->name);
+				printk(KERN_INFO "%s: Chargesum is %d\n", p->dev->name,
+				       lp->charge);
+				isdn_net_unbind_channel(lp);
+				return 1;
+			}
+			break;
+#ifdef CONFIG_ISDN_X25
+		case ISDN_STAT_BHUP:
+			/* B-Channel-hangup */
+			/* try if there are generic encap protocol
+			   receiver routines and signal the closure of
+			   the link */
+			if (pops && pops->disconn_ind) {
+				pops->disconn_ind(cprot);
+				return 1;
+			}
+			break;
+#endif /* CONFIG_ISDN_X25 */
+		case ISDN_STAT_BCONN:
+			/* B-Channel is up */
+			isdn_net_zero_frame_cnt(lp);
+			switch (lp->dialstate) {
+			case 5:
+			case 6:
+			case 7:
+			case 8:
+			case 9:
+			case 10:
+			case 12:
+				if (lp->dialstate <= 6) {
+					dev->usage[idx] |= ISDN_USAGE_OUTGOING;
+					isdn_info_update();
+				} else
+					dev->rx_netdev[idx] = p;
+				lp->dialstate = 0;
+				isdn_timer_ctrl(ISDN_TIMER_NETHANGUP, 1);
+				if (lp->p_encap == ISDN_NET_ENCAP_CISCOHDLCK)
+					isdn_net_ciscohdlck_connected(lp);
+				if (lp->p_encap != ISDN_NET_ENCAP_SYNCPPP) {
+					if (lp->master) { /* is lp a slave? */
+						isdn_net_dev *nd = ISDN_MASTER_PRIV(lp)->netdev;
+						isdn_net_add_to_bundle(nd, lp);
+					}
+				}
+				printk(KERN_INFO "isdn_net: %s connected\n", p->dev->name);
+				/* If first Chargeinfo comes before B-Channel connect,
+				 * we correct the timestamp here.
+				 */
+				lp->chargetime = jiffies;
+
+				/* reset dial-timeout */
+				lp->dialstarted = 0;
+				lp->dialwait_timer = 0;
+
+#ifdef CONFIG_ISDN_PPP
+				if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+					isdn_ppp_wakeup_daemon(lp);
+#endif
+#ifdef CONFIG_ISDN_X25
+				/* try if there are generic concap receiver routines */
+				if (pops)
+					if (pops->connect_ind)
+						pops->connect_ind(cprot);
+#endif /* CONFIG_ISDN_X25 */
+				/* ppp needs to do negotiations first */
+				if (lp->p_encap != ISDN_NET_ENCAP_SYNCPPP)
+					isdn_net_device_wake_queue(lp);
+				return 1;
+			}
+			break;
+		case ISDN_STAT_NODCH:
+			/* No D-Channel avail. */
+			if (lp->dialstate == 4) {
+				lp->dialstate--;
+				return 1;
+			}
+			break;
+		case ISDN_STAT_CINF:
+			/* Charge-info from TelCo. Calculate interval between
+			 * charge-infos and set timestamp for last info for
+			 * usage by isdn_net_autohup()
+			 */
+			lp->charge++;
+			if (lp->hupflags & ISDN_HAVECHARGE) {
+				lp->hupflags &= ~ISDN_WAITCHARGE;
+				lp->chargeint = jiffies - lp->chargetime - (2 * HZ);
+			}
+			if (lp->hupflags & ISDN_WAITCHARGE)
+				lp->hupflags |= ISDN_HAVECHARGE;
+			lp->chargetime = jiffies;
+			printk(KERN_DEBUG "isdn_net: Got CINF chargetime of %s now %lu\n",
+			       p->dev->name, lp->chargetime);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Perform dialout for net-interfaces and timeout-handling for
+ * D-Channel-up and B-Channel-up Messages.
+ * This function is initially called from within isdn_net_start_xmit() or
+ * or isdn_net_find_icall() after initializing the dialstate for an
+ * interface. If further calls are needed, the function schedules itself
+ * for a timer-callback via isdn_timer_function().
+ * The dialstate is also affected by incoming status-messages from
+ * the ISDN-Channel which are handled in isdn_net_stat_callback() above.
+ */
+void
+isdn_net_dial(void)
+{
+	isdn_net_dev *p = dev->netdev;
+	int anymore = 0;
+	int i;
+	isdn_ctrl cmd;
+	u_char *phone_number;
+
+	while (p) {
+		isdn_net_local *lp = p->local;
+
+#ifdef ISDN_DEBUG_NET_DIAL
+		if (lp->dialstate)
+			printk(KERN_DEBUG "%s: dialstate=%d\n", p->dev->name, lp->dialstate);
+#endif
+		switch (lp->dialstate) {
+		case 0:
+			/* Nothing to do for this interface */
+			break;
+		case 1:
+			/* Initiate dialout. Set phone-number-pointer to first number
+			 * of interface.
+			 */
+			lp->dial = lp->phone[1];
+			if (!lp->dial) {
+				printk(KERN_WARNING "%s: phone number deleted?\n",
+				       p->dev->name);
+				isdn_net_hangup(p->dev);
+				break;
+			}
+			anymore = 1;
+
+			if (lp->dialtimeout > 0)
+				if (lp->dialstarted == 0 || time_after(jiffies, lp->dialstarted + lp->dialtimeout + lp->dialwait)) {
+					lp->dialstarted = jiffies;
+					lp->dialwait_timer = 0;
+				}
+
+			lp->dialstate++;
+			/* Fall through */
+		case 2:
+			/* Prepare dialing. Clear EAZ, then set EAZ. */
+			cmd.driver = lp->isdn_device;
+			cmd.arg = lp->isdn_channel;
+			cmd.command = ISDN_CMD_CLREAZ;
+			isdn_command(&cmd);
+			sprintf(cmd.parm.num, "%s", isdn_map_eaz2msn(lp->msn, cmd.driver));
+			cmd.command = ISDN_CMD_SETEAZ;
+			isdn_command(&cmd);
+			lp->dialretry = 0;
+			anymore = 1;
+			lp->dialstate++;
+			/* Fall through */
+		case 3:
+			/* Setup interface, dial current phone-number, switch to next number.
+			 * If list of phone-numbers is exhausted, increment
+			 * retry-counter.
+			 */
+			if (dev->global_flags & ISDN_GLOBAL_STOPPED || (ISDN_NET_DIALMODE(*lp) == ISDN_NET_DM_OFF)) {
+				char *s;
+				if (dev->global_flags & ISDN_GLOBAL_STOPPED)
+					s = "dial suppressed: isdn system stopped";
+				else
+					s = "dial suppressed: dialmode `off'";
+				isdn_net_unreachable(p->dev, NULL, s);
+				isdn_net_hangup(p->dev);
+				break;
+			}
+			cmd.driver = lp->isdn_device;
+			cmd.command = ISDN_CMD_SETL2;
+			cmd.arg = lp->isdn_channel + (lp->l2_proto << 8);
+			isdn_command(&cmd);
+			cmd.driver = lp->isdn_device;
+			cmd.command = ISDN_CMD_SETL3;
+			cmd.arg = lp->isdn_channel + (lp->l3_proto << 8);
+			isdn_command(&cmd);
+			cmd.driver = lp->isdn_device;
+			cmd.arg = lp->isdn_channel;
+			if (!lp->dial) {
+				printk(KERN_WARNING "%s: phone number deleted?\n",
+				       p->dev->name);
+				isdn_net_hangup(p->dev);
+				break;
+			}
+			if (!strncmp(lp->dial->num, "LEASED", strlen("LEASED"))) {
+				lp->dialstate = 4;
+				printk(KERN_INFO "%s: Open leased line ...\n", p->dev->name);
+			} else {
+				if (lp->dialtimeout > 0)
+					if (time_after(jiffies, lp->dialstarted + lp->dialtimeout)) {
+						lp->dialwait_timer = jiffies + lp->dialwait;
+						lp->dialstarted = 0;
+						isdn_net_unreachable(p->dev, NULL, "dial: timed out");
+						isdn_net_hangup(p->dev);
+						break;
+					}
+
+				cmd.driver = lp->isdn_device;
+				cmd.command = ISDN_CMD_DIAL;
+				cmd.parm.setup.si2 = 0;
+
+				/* check for DOV */
+				phone_number = lp->dial->num;
+				if ((*phone_number == 'v') ||
+				    (*phone_number == 'V')) { /* DOV call */
+					cmd.parm.setup.si1 = 1;
+				} else { /* DATA call */
+					cmd.parm.setup.si1 = 7;
+				}
+
+				strcpy(cmd.parm.setup.phone, phone_number);
+				/*
+				 * Switch to next number or back to start if at end of list.
+				 */
+				if (!(lp->dial = (isdn_net_phone *) lp->dial->next)) {
+					lp->dial = lp->phone[1];
+					lp->dialretry++;
+
+					if (lp->dialretry > lp->dialmax) {
+						if (lp->dialtimeout == 0) {
+							lp->dialwait_timer = jiffies + lp->dialwait;
+							lp->dialstarted = 0;
+							isdn_net_unreachable(p->dev, NULL, "dial: tried all numbers dialmax times");
+						}
+						isdn_net_hangup(p->dev);
+						break;
+					}
+				}
+				sprintf(cmd.parm.setup.eazmsn, "%s",
+					isdn_map_eaz2msn(lp->msn, cmd.driver));
+				i = isdn_dc2minor(lp->isdn_device, lp->isdn_channel);
+				if (i >= 0) {
+					strcpy(dev->num[i], cmd.parm.setup.phone);
+					dev->usage[i] |= ISDN_USAGE_OUTGOING;
+					isdn_info_update();
+				}
+				printk(KERN_INFO "%s: dialing %d %s... %s\n", p->dev->name,
+				       lp->dialretry, cmd.parm.setup.phone,
+				       (cmd.parm.setup.si1 == 1) ? "DOV" : "");
+				lp->dtimer = 0;
+#ifdef ISDN_DEBUG_NET_DIAL
+				printk(KERN_DEBUG "dial: d=%d c=%d\n", lp->isdn_device,
+				       lp->isdn_channel);
+#endif
+				isdn_command(&cmd);
+			}
+			lp->huptimer = 0;
+			lp->outgoing = 1;
+			if (lp->chargeint) {
+				lp->hupflags |= ISDN_HAVECHARGE;
+				lp->hupflags &= ~ISDN_WAITCHARGE;
+			} else {
+				lp->hupflags |= ISDN_WAITCHARGE;
+				lp->hupflags &= ~ISDN_HAVECHARGE;
+			}
+			anymore = 1;
+			lp->dialstate =
+				(lp->cbdelay &&
+				 (lp->flags & ISDN_NET_CBOUT)) ? 12 : 4;
+			break;
+		case 4:
+			/* Wait for D-Channel-connect.
+			 * If timeout, switch back to state 3.
+			 * Dialmax-handling moved to state 3.
+			 */
+			if (lp->dtimer++ > ISDN_TIMER_DTIMEOUT10)
+				lp->dialstate = 3;
+			anymore = 1;
+			break;
+		case 5:
+			/* Got D-Channel-Connect, send B-Channel-request */
+			cmd.driver = lp->isdn_device;
+			cmd.arg = lp->isdn_channel;
+			cmd.command = ISDN_CMD_ACCEPTB;
+			anymore = 1;
+			lp->dtimer = 0;
+			lp->dialstate++;
+			isdn_command(&cmd);
+			break;
+		case 6:
+			/* Wait for B- or D-Channel-connect. If timeout,
+			 * switch back to state 3.
+			 */
+#ifdef ISDN_DEBUG_NET_DIAL
+			printk(KERN_DEBUG "dialtimer2: %d\n", lp->dtimer);
+#endif
+			if (lp->dtimer++ > ISDN_TIMER_DTIMEOUT10)
+				lp->dialstate = 3;
+			anymore = 1;
+			break;
+		case 7:
+			/* Got incoming Call, setup L2 and L3 protocols,
+			 * then wait for D-Channel-connect
+			 */
+#ifdef ISDN_DEBUG_NET_DIAL
+			printk(KERN_DEBUG "dialtimer4: %d\n", lp->dtimer);
+#endif
+			cmd.driver = lp->isdn_device;
+			cmd.command = ISDN_CMD_SETL2;
+			cmd.arg = lp->isdn_channel + (lp->l2_proto << 8);
+			isdn_command(&cmd);
+			cmd.driver = lp->isdn_device;
+			cmd.command = ISDN_CMD_SETL3;
+			cmd.arg = lp->isdn_channel + (lp->l3_proto << 8);
+			isdn_command(&cmd);
+			if (lp->dtimer++ > ISDN_TIMER_DTIMEOUT15)
+				isdn_net_hangup(p->dev);
+			else {
+				anymore = 1;
+				lp->dialstate++;
+			}
+			break;
+		case 9:
+			/* Got incoming D-Channel-Connect, send B-Channel-request */
+			cmd.driver = lp->isdn_device;
+			cmd.arg = lp->isdn_channel;
+			cmd.command = ISDN_CMD_ACCEPTB;
+			isdn_command(&cmd);
+			anymore = 1;
+			lp->dtimer = 0;
+			lp->dialstate++;
+			break;
+		case 8:
+		case 10:
+			/*  Wait for B- or D-channel-connect */
+#ifdef ISDN_DEBUG_NET_DIAL
+			printk(KERN_DEBUG "dialtimer4: %d\n", lp->dtimer);
+#endif
+			if (lp->dtimer++ > ISDN_TIMER_DTIMEOUT10)
+				isdn_net_hangup(p->dev);
+			else
+				anymore = 1;
+			break;
+		case 11:
+			/* Callback Delay */
+			if (lp->dtimer++ > lp->cbdelay)
+				lp->dialstate = 1;
+			anymore = 1;
+			break;
+		case 12:
+			/* Remote does callback. Hangup after cbdelay, then wait for incoming
+			 * call (in state 4).
+			 */
+			if (lp->dtimer++ > lp->cbdelay)
+			{
+				printk(KERN_INFO "%s: hangup waiting for callback ...\n", p->dev->name);
+				lp->dtimer = 0;
+				lp->dialstate = 4;
+				cmd.driver = lp->isdn_device;
+				cmd.command = ISDN_CMD_HANGUP;
+				cmd.arg = lp->isdn_channel;
+				isdn_command(&cmd);
+				isdn_all_eaz(lp->isdn_device, lp->isdn_channel);
+			}
+			anymore = 1;
+			break;
+		default:
+			printk(KERN_WARNING "isdn_net: Illegal dialstate %d for device %s\n",
+			       lp->dialstate, p->dev->name);
+		}
+		p = (isdn_net_dev *) p->next;
+	}
+	isdn_timer_ctrl(ISDN_TIMER_NETDIAL, anymore);
+}
+
+/*
+ * Perform hangup for a net-interface.
+ */
+void
+isdn_net_hangup(struct net_device *d)
+{
+	isdn_net_local *lp = netdev_priv(d);
+	isdn_ctrl cmd;
+#ifdef CONFIG_ISDN_X25
+	struct concap_proto *cprot = lp->netdev->cprot;
+	struct concap_proto_ops *pops = cprot ? cprot->pops : NULL;
+#endif
+
+	if (lp->flags & ISDN_NET_CONNECTED) {
+		if (lp->slave != NULL) {
+			isdn_net_local *slp = ISDN_SLAVE_PRIV(lp);
+			if (slp->flags & ISDN_NET_CONNECTED) {
+				printk(KERN_INFO
+				       "isdn_net: hang up slave %s before %s\n",
+				       lp->slave->name, d->name);
+				isdn_net_hangup(lp->slave);
+			}
+		}
+		printk(KERN_INFO "isdn_net: local hangup %s\n", d->name);
+#ifdef CONFIG_ISDN_PPP
+		if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+			isdn_ppp_free(lp);
+#endif
+		isdn_net_lp_disconnected(lp);
+#ifdef CONFIG_ISDN_X25
+		/* try if there are generic encap protocol
+		   receiver routines and signal the closure of
+		   the link */
+		if (pops && pops->disconn_ind)
+			pops->disconn_ind(cprot);
+#endif /* CONFIG_ISDN_X25 */
+
+		cmd.driver = lp->isdn_device;
+		cmd.command = ISDN_CMD_HANGUP;
+		cmd.arg = lp->isdn_channel;
+		isdn_command(&cmd);
+		printk(KERN_INFO "%s: Chargesum is %d\n", d->name, lp->charge);
+		isdn_all_eaz(lp->isdn_device, lp->isdn_channel);
+	}
+	isdn_net_unbind_channel(lp);
+}
+
+typedef struct {
+	__be16 source;
+	__be16 dest;
+} ip_ports;
+
+static void
+isdn_net_log_skb(struct sk_buff *skb, isdn_net_local *lp)
+{
+	/* hopefully, this was set correctly */
+	const u_char *p = skb_network_header(skb);
+	unsigned short proto = ntohs(skb->protocol);
+	int data_ofs;
+	ip_ports *ipp;
+	char addinfo[100];
+
+	addinfo[0] = '\0';
+	/* This check stolen from 2.1.72 dev_queue_xmit_nit() */
+	if (p < skb->data || skb_network_header(skb) >= skb_tail_pointer(skb)) {
+		/* fall back to old isdn_net_log_packet method() */
+		char *buf = skb->data;
+
+		printk(KERN_DEBUG "isdn_net: protocol %04x is buggy, dev %s\n", skb->protocol, lp->netdev->dev->name);
+		p = buf;
+		proto = ETH_P_IP;
+		switch (lp->p_encap) {
+		case ISDN_NET_ENCAP_IPTYP:
+			proto = ntohs(*(__be16 *)&buf[0]);
+			p = &buf[2];
+			break;
+		case ISDN_NET_ENCAP_ETHER:
+			proto = ntohs(*(__be16 *)&buf[12]);
+			p = &buf[14];
+			break;
+		case ISDN_NET_ENCAP_CISCOHDLC:
+			proto = ntohs(*(__be16 *)&buf[2]);
+			p = &buf[4];
+			break;
+#ifdef CONFIG_ISDN_PPP
+		case ISDN_NET_ENCAP_SYNCPPP:
+			proto = ntohs(skb->protocol);
+			p = &buf[IPPP_MAX_HEADER];
+			break;
+#endif
+		}
+	}
+	data_ofs = ((p[0] & 15) * 4);
+	switch (proto) {
+	case ETH_P_IP:
+		switch (p[9]) {
+		case 1:
+			strcpy(addinfo, " ICMP");
+			break;
+		case 2:
+			strcpy(addinfo, " IGMP");
+			break;
+		case 4:
+			strcpy(addinfo, " IPIP");
+			break;
+		case 6:
+			ipp = (ip_ports *) (&p[data_ofs]);
+			sprintf(addinfo, " TCP, port: %d -> %d", ntohs(ipp->source),
+				ntohs(ipp->dest));
+			break;
+		case 8:
+			strcpy(addinfo, " EGP");
+			break;
+		case 12:
+			strcpy(addinfo, " PUP");
+			break;
+		case 17:
+			ipp = (ip_ports *) (&p[data_ofs]);
+			sprintf(addinfo, " UDP, port: %d -> %d", ntohs(ipp->source),
+				ntohs(ipp->dest));
+			break;
+		case 22:
+			strcpy(addinfo, " IDP");
+			break;
+		}
+		printk(KERN_INFO "OPEN: %pI4 -> %pI4%s\n",
+		       p + 12, p + 16, addinfo);
+		break;
+	case ETH_P_ARP:
+		printk(KERN_INFO "OPEN: ARP %pI4 -> *.*.*.* ?%pI4\n",
+		       p + 14, p + 24);
+		break;
+	}
+}
+
+/*
+ * this function is used to send supervisory data, i.e. data which was
+ * not received from the network layer, but e.g. frames from ipppd, CCP
+ * reset frames etc.
+ */
+void isdn_net_write_super(isdn_net_local *lp, struct sk_buff *skb)
+{
+	if (in_irq()) {
+		// we can't grab the lock from irq context,
+		// so we just queue the packet
+		skb_queue_tail(&lp->super_tx_queue, skb);
+		schedule_work(&lp->tqueue);
+		return;
+	}
+
+	spin_lock_bh(&lp->xmit_lock);
+	if (!isdn_net_lp_busy(lp)) {
+		isdn_net_writebuf_skb(lp, skb);
+	} else {
+		skb_queue_tail(&lp->super_tx_queue, skb);
+	}
+	spin_unlock_bh(&lp->xmit_lock);
+}
+
+/*
+ * called from tq_immediate
+ */
+static void isdn_net_softint(struct work_struct *work)
+{
+	isdn_net_local *lp = container_of(work, isdn_net_local, tqueue);
+	struct sk_buff *skb;
+
+	spin_lock_bh(&lp->xmit_lock);
+	while (!isdn_net_lp_busy(lp)) {
+		skb = skb_dequeue(&lp->super_tx_queue);
+		if (!skb)
+			break;
+		isdn_net_writebuf_skb(lp, skb);
+	}
+	spin_unlock_bh(&lp->xmit_lock);
+}
+
+/*
+ * all frames sent from the (net) LL to a HL driver should go via this function
+ * it's serialized by the caller holding the lp->xmit_lock spinlock
+ */
+void isdn_net_writebuf_skb(isdn_net_local *lp, struct sk_buff *skb)
+{
+	int ret;
+	int len = skb->len;     /* save len */
+
+	/* before obtaining the lock the caller should have checked that
+	   the lp isn't busy */
+	if (isdn_net_lp_busy(lp)) {
+		printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__);
+		goto error;
+	}
+
+	if (!(lp->flags & ISDN_NET_CONNECTED)) {
+		printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__);
+		goto error;
+	}
+	ret = isdn_writebuf_skb_stub(lp->isdn_device, lp->isdn_channel, 1, skb);
+	if (ret != len) {
+		/* we should never get here */
+		printk(KERN_WARNING "%s: HL driver queue full\n", lp->netdev->dev->name);
+		goto error;
+	}
+
+	lp->transcount += len;
+	isdn_net_inc_frame_cnt(lp);
+	return;
+
+error:
+	dev_kfree_skb(skb);
+	lp->stats.tx_errors++;
+
+}
+
+
+/*
+ *  Helper function for isdn_net_start_xmit.
+ *  When called, the connection is already established.
+ *  Based on cps-calculation, check if device is overloaded.
+ *  If so, and if a slave exists, trigger dialing for it.
+ *  If any slave is online, deliver packets using a simple round robin
+ *  scheme.
+ *
+ *  Return: 0 on success, !0 on failure.
+ */
+
+static int
+isdn_net_xmit(struct net_device *ndev, struct sk_buff *skb)
+{
+	isdn_net_dev *nd;
+	isdn_net_local *slp;
+	isdn_net_local *lp = netdev_priv(ndev);
+	int retv = NETDEV_TX_OK;
+
+	if (((isdn_net_local *) netdev_priv(ndev))->master) {
+		printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__);
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	/* For the other encaps the header has already been built */
+#ifdef CONFIG_ISDN_PPP
+	if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP) {
+		return isdn_ppp_xmit(skb, ndev);
+	}
+#endif
+	nd = ((isdn_net_local *) netdev_priv(ndev))->netdev;
+	lp = isdn_net_get_locked_lp(nd);
+	if (!lp) {
+		printk(KERN_WARNING "%s: all channels busy - requeuing!\n", ndev->name);
+		return NETDEV_TX_BUSY;
+	}
+	/* we have our lp locked from now on */
+
+	/* Reset hangup-timeout */
+	lp->huptimer = 0; // FIXME?
+	isdn_net_writebuf_skb(lp, skb);
+	spin_unlock_bh(&lp->xmit_lock);
+
+	/* the following stuff is here for backwards compatibility.
+	 * in future, start-up and hangup of slaves (based on current load)
+	 * should move to userspace and get based on an overall cps
+	 * calculation
+	 */
+	if (lp->cps > lp->triggercps) {
+		if (lp->slave) {
+			if (!lp->sqfull) {
+				/* First time overload: set timestamp only */
+				lp->sqfull = 1;
+				lp->sqfull_stamp = jiffies;
+			} else {
+				/* subsequent overload: if slavedelay exceeded, start dialing */
+				if (time_after(jiffies, lp->sqfull_stamp + lp->slavedelay)) {
+					slp = ISDN_SLAVE_PRIV(lp);
+					if (!(slp->flags & ISDN_NET_CONNECTED)) {
+						isdn_net_force_dial_lp(ISDN_SLAVE_PRIV(lp));
+					}
+				}
+			}
+		}
+	} else {
+		if (lp->sqfull && time_after(jiffies, lp->sqfull_stamp + lp->slavedelay + (10 * HZ))) {
+			lp->sqfull = 0;
+		}
+		/* this is a hack to allow auto-hangup for slaves on moderate loads */
+		nd->queue = nd->local;
+	}
+
+	return retv;
+
+}
+
+static void
+isdn_net_adjust_hdr(struct sk_buff *skb, struct net_device *dev)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+	if (!skb)
+		return;
+	if (lp->p_encap == ISDN_NET_ENCAP_ETHER) {
+		const int pullsize = skb_network_offset(skb) - ETH_HLEN;
+		if (pullsize > 0) {
+			printk(KERN_DEBUG "isdn_net: Pull junk %d\n", pullsize);
+			skb_pull(skb, pullsize);
+		}
+	}
+}
+
+
+static void isdn_net_tx_timeout(struct net_device *ndev)
+{
+	isdn_net_local *lp = netdev_priv(ndev);
+
+	printk(KERN_WARNING "isdn_tx_timeout dev %s dialstate %d\n", ndev->name, lp->dialstate);
+	if (!lp->dialstate) {
+		lp->stats.tx_errors++;
+		/*
+		 * There is a certain probability that this currently
+		 * works at all because if we always wake up the interface,
+		 * then upper layer will try to send the next packet
+		 * immediately. And then, the old clean_up logic in the
+		 * driver will hopefully continue to work as it used to do.
+		 *
+		 * This is rather primitive right know, we better should
+		 * clean internal queues here, in particular for multilink and
+		 * ppp, and reset HL driver's channel, too.   --HE
+		 *
+		 * actually, this may not matter at all, because ISDN hardware
+		 * should not see transmitter hangs at all IMO
+		 * changed KERN_DEBUG to KERN_WARNING to find out if this is
+		 * ever called   --KG
+		 */
+	}
+	netif_trans_update(ndev);
+	netif_wake_queue(ndev);
+}
+
+/*
+ * Try sending a packet.
+ * If this interface isn't connected to a ISDN-Channel, find a free channel,
+ * and start dialing.
+ */
+static netdev_tx_t
+isdn_net_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+	isdn_net_local *lp = netdev_priv(ndev);
+#ifdef CONFIG_ISDN_X25
+	struct concap_proto *cprot = lp->netdev->cprot;
+/* At this point hard_start_xmit() passes control to the encapsulation
+   protocol (if present).
+   For X.25 auto-dialing is completly bypassed because:
+   - It does not conform with the semantics of a reliable datalink
+   service as needed by X.25 PLP.
+   - I don't want that the interface starts dialing when the network layer
+   sends a message which requests to disconnect the lapb link (or if it
+   sends any other message not resulting in data transmission).
+   Instead, dialing will be initiated by the encapsulation protocol entity
+   when a dl_establish request is received from the upper layer.
+*/
+	if (cprot && cprot->pops) {
+		int ret = cprot->pops->encap_and_xmit(cprot, skb);
+
+		if (ret)
+			netif_stop_queue(ndev);
+		return ret;
+	} else
+#endif
+		/* auto-dialing xmit function */
+	{
+#ifdef ISDN_DEBUG_NET_DUMP
+		u_char *buf;
+#endif
+		isdn_net_adjust_hdr(skb, ndev);
+#ifdef ISDN_DEBUG_NET_DUMP
+		buf = skb->data;
+		isdn_dumppkt("S:", buf, skb->len, 40);
+#endif
+
+		if (!(lp->flags & ISDN_NET_CONNECTED)) {
+			int chi;
+			/* only do autodial if allowed by config */
+			if (!(ISDN_NET_DIALMODE(*lp) == ISDN_NET_DM_AUTO)) {
+				isdn_net_unreachable(ndev, skb, "dial rejected: interface not in dialmode `auto'");
+				dev_kfree_skb(skb);
+				return NETDEV_TX_OK;
+			}
+			if (lp->phone[1]) {
+				ulong flags;
+
+				if (lp->dialwait_timer <= 0)
+					if (lp->dialstarted > 0 && lp->dialtimeout > 0 && time_before(jiffies, lp->dialstarted + lp->dialtimeout + lp->dialwait))
+						lp->dialwait_timer = lp->dialstarted + lp->dialtimeout + lp->dialwait;
+
+				if (lp->dialwait_timer > 0) {
+					if (time_before(jiffies, lp->dialwait_timer)) {
+						isdn_net_unreachable(ndev, skb, "dial rejected: retry-time not reached");
+						dev_kfree_skb(skb);
+						return NETDEV_TX_OK;
+					} else
+						lp->dialwait_timer = 0;
+				}
+				/* Grab a free ISDN-Channel */
+				spin_lock_irqsave(&dev->lock, flags);
+				if (((chi =
+				      isdn_get_free_channel(
+					      ISDN_USAGE_NET,
+					      lp->l2_proto,
+					      lp->l3_proto,
+					      lp->pre_device,
+					      lp->pre_channel,
+					      lp->msn)
+					     ) < 0) &&
+				    ((chi =
+				      isdn_get_free_channel(
+					      ISDN_USAGE_NET,
+					      lp->l2_proto,
+					      lp->l3_proto,
+					      lp->pre_device,
+					      lp->pre_channel^1,
+					      lp->msn)
+					    ) < 0)) {
+					spin_unlock_irqrestore(&dev->lock, flags);
+					isdn_net_unreachable(ndev, skb,
+							     "No channel");
+					dev_kfree_skb(skb);
+					return NETDEV_TX_OK;
+				}
+				/* Log packet, which triggered dialing */
+				if (dev->net_verbose)
+					isdn_net_log_skb(skb, lp);
+				lp->dialstate = 1;
+				/* Connect interface with channel */
+				isdn_net_bind_channel(lp, chi);
+#ifdef CONFIG_ISDN_PPP
+				if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP) {
+					/* no 'first_skb' handling for syncPPP */
+					if (isdn_ppp_bind(lp) < 0) {
+						dev_kfree_skb(skb);
+						isdn_net_unbind_channel(lp);
+						spin_unlock_irqrestore(&dev->lock, flags);
+						return NETDEV_TX_OK;	/* STN (skb to nirvana) ;) */
+					}
+#ifdef CONFIG_IPPP_FILTER
+					if (isdn_ppp_autodial_filter(skb, lp)) {
+						isdn_ppp_free(lp);
+						isdn_net_unbind_channel(lp);
+						spin_unlock_irqrestore(&dev->lock, flags);
+						isdn_net_unreachable(ndev, skb, "dial rejected: packet filtered");
+						dev_kfree_skb(skb);
+						return NETDEV_TX_OK;
+					}
+#endif
+					spin_unlock_irqrestore(&dev->lock, flags);
+					isdn_net_dial();	/* Initiate dialing */
+					netif_stop_queue(ndev);
+					return NETDEV_TX_BUSY;	/* let upper layer requeue skb packet */
+				}
+#endif
+				/* Initiate dialing */
+				spin_unlock_irqrestore(&dev->lock, flags);
+				isdn_net_dial();
+				isdn_net_device_stop_queue(lp);
+				return NETDEV_TX_BUSY;
+			} else {
+				isdn_net_unreachable(ndev, skb,
+						     "No phone number");
+				dev_kfree_skb(skb);
+				return NETDEV_TX_OK;
+			}
+		} else {
+			/* Device is connected to an ISDN channel */
+			netif_trans_update(ndev);
+			if (!lp->dialstate) {
+				/* ISDN connection is established, try sending */
+				int ret;
+				ret = (isdn_net_xmit(ndev, skb));
+				if (ret) netif_stop_queue(ndev);
+				return ret;
+			} else
+				netif_stop_queue(ndev);
+		}
+	}
+	return NETDEV_TX_BUSY;
+}
+
+/*
+ * Shutdown a net-interface.
+ */
+static int
+isdn_net_close(struct net_device *dev)
+{
+	struct net_device *p;
+#ifdef CONFIG_ISDN_X25
+	struct concap_proto *cprot =
+		((isdn_net_local *)netdev_priv(dev))->netdev->cprot;
+	/* printk(KERN_DEBUG "isdn_net_close %s\n" , dev-> name); */
+#endif
+
+#ifdef CONFIG_ISDN_X25
+	if (cprot && cprot->pops) cprot->pops->close(cprot);
+#endif
+	netif_stop_queue(dev);
+	p = MASTER_TO_SLAVE(dev);
+	if (p) {
+		/* If this interface has slaves, stop them also */
+		while (p) {
+#ifdef CONFIG_ISDN_X25
+			cprot = ((isdn_net_local *)netdev_priv(p))
+				->netdev->cprot;
+			if (cprot && cprot->pops)
+				cprot->pops->close(cprot);
+#endif
+			isdn_net_hangup(p);
+			p = MASTER_TO_SLAVE(p);
+		}
+	}
+	isdn_net_hangup(dev);
+	isdn_unlock_drivers();
+	return 0;
+}
+
+/*
+ * Get statistics
+ */
+static struct net_device_stats *
+isdn_net_get_stats(struct net_device *dev)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+	return &lp->stats;
+}
+
+/*      This is simply a copy from std. eth.c EXCEPT we pull ETH_HLEN
+ *      instead of dev->hard_header_len off. This is done because the
+ *      lowlevel-driver has already pulled off its stuff when we get
+ *      here and this routine only gets called with p_encap == ETHER.
+ *      Determine the packet's protocol ID. The rule here is that we
+ *      assume 802.3 if the type field is short enough to be a length.
+ *      This is normal practice and works for any 'now in use' protocol.
+ */
+
+static __be16
+isdn_net_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ethhdr *eth;
+	unsigned char *rawp;
+
+	skb_reset_mac_header(skb);
+	skb_pull(skb, ETH_HLEN);
+	eth = eth_hdr(skb);
+
+	if (*eth->h_dest & 1) {
+		if (ether_addr_equal(eth->h_dest, dev->broadcast))
+			skb->pkt_type = PACKET_BROADCAST;
+		else
+			skb->pkt_type = PACKET_MULTICAST;
+	}
+	/*
+	 *      This ALLMULTI check should be redundant by 1.4
+	 *      so don't forget to remove it.
+	 */
+
+	else if (dev->flags & (IFF_PROMISC /*| IFF_ALLMULTI*/)) {
+		if (!ether_addr_equal(eth->h_dest, dev->dev_addr))
+			skb->pkt_type = PACKET_OTHERHOST;
+	}
+	if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
+		return eth->h_proto;
+
+	rawp = skb->data;
+
+	/*
+	 *      This is a magic hack to spot IPX packets. Older Novell breaks
+	 *      the protocol design and runs IPX over 802.3 without an 802.2 LLC
+	 *      layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
+	 *      won't work for fault tolerant netware but does for the rest.
+	 */
+	if (*(unsigned short *) rawp == 0xFFFF)
+		return htons(ETH_P_802_3);
+	/*
+	 *      Real 802.2 LLC
+	 */
+	return htons(ETH_P_802_2);
+}
+
+
+/*
+ * CISCO HDLC keepalive specific stuff
+ */
+static struct sk_buff*
+isdn_net_ciscohdlck_alloc_skb(isdn_net_local *lp, int len)
+{
+	unsigned short hl = dev->drv[lp->isdn_device]->interface->hl_hdrlen;
+	struct sk_buff *skb;
+
+	skb = alloc_skb(hl + len, GFP_ATOMIC);
+	if (skb)
+		skb_reserve(skb, hl);
+	else
+		printk("isdn out of mem at %s:%d!\n", __FILE__, __LINE__);
+	return skb;
+}
+
+/* cisco hdlck device private ioctls */
+static int
+isdn_ciscohdlck_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+	unsigned long len = 0;
+	unsigned long expires = 0;
+	int tmp = 0;
+	int period = lp->cisco_keepalive_period;
+	s8 debserint = lp->cisco_debserint;
+	int rc = 0;
+
+	if (lp->p_encap != ISDN_NET_ENCAP_CISCOHDLCK)
+		return -EINVAL;
+
+	switch (cmd) {
+		/* get/set keepalive period */
+	case SIOCGKEEPPERIOD:
+		len = (unsigned long)sizeof(lp->cisco_keepalive_period);
+		if (copy_to_user(ifr->ifr_data,
+				 &lp->cisco_keepalive_period, len))
+			rc = -EFAULT;
+		break;
+	case SIOCSKEEPPERIOD:
+		tmp = lp->cisco_keepalive_period;
+		len = (unsigned long)sizeof(lp->cisco_keepalive_period);
+		if (copy_from_user(&period, ifr->ifr_data, len))
+			rc = -EFAULT;
+		if ((period > 0) && (period <= 32767))
+			lp->cisco_keepalive_period = period;
+		else
+			rc = -EINVAL;
+		if (!rc && (tmp != lp->cisco_keepalive_period)) {
+			expires = (unsigned long)(jiffies +
+						  lp->cisco_keepalive_period * HZ);
+			mod_timer(&lp->cisco_timer, expires);
+			printk(KERN_INFO "%s: Keepalive period set "
+			       "to %d seconds.\n",
+			       dev->name, lp->cisco_keepalive_period);
+		}
+		break;
+
+		/* get/set debugging */
+	case SIOCGDEBSERINT:
+		len = (unsigned long)sizeof(lp->cisco_debserint);
+		if (copy_to_user(ifr->ifr_data,
+				 &lp->cisco_debserint, len))
+			rc = -EFAULT;
+		break;
+	case SIOCSDEBSERINT:
+		len = (unsigned long)sizeof(lp->cisco_debserint);
+		if (copy_from_user(&debserint,
+				   ifr->ifr_data, len))
+			rc = -EFAULT;
+		if ((debserint >= 0) && (debserint <= 64))
+			lp->cisco_debserint = debserint;
+		else
+			rc = -EINVAL;
+		break;
+
+	default:
+		rc = -EINVAL;
+		break;
+	}
+	return (rc);
+}
+
+
+static int isdn_net_ioctl(struct net_device *dev,
+			  struct ifreq *ifr, int cmd)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+
+	switch (lp->p_encap) {
+#ifdef CONFIG_ISDN_PPP
+	case ISDN_NET_ENCAP_SYNCPPP:
+		return isdn_ppp_dev_ioctl(dev, ifr, cmd);
+#endif
+	case ISDN_NET_ENCAP_CISCOHDLCK:
+		return isdn_ciscohdlck_dev_ioctl(dev, ifr, cmd);
+	default:
+		return -EINVAL;
+	}
+}
+
+/* called via cisco_timer.function */
+static void
+isdn_net_ciscohdlck_slarp_send_keepalive(struct timer_list *t)
+{
+	isdn_net_local *lp = from_timer(lp, t, cisco_timer);
+	struct sk_buff *skb;
+	unsigned char *p;
+	unsigned long last_cisco_myseq = lp->cisco_myseq;
+	int myseq_diff = 0;
+
+	if (!(lp->flags & ISDN_NET_CONNECTED) || lp->dialstate) {
+		printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__);
+		return;
+	}
+	lp->cisco_myseq++;
+
+	myseq_diff = (lp->cisco_myseq - lp->cisco_mineseen);
+	if ((lp->cisco_line_state) && ((myseq_diff >= 3) || (myseq_diff <= -3))) {
+		/* line up -> down */
+		lp->cisco_line_state = 0;
+		printk(KERN_WARNING
+		       "UPDOWN: Line protocol on Interface %s,"
+		       " changed state to down\n", lp->netdev->dev->name);
+		/* should stop routing higher-level data across */
+	} else if ((!lp->cisco_line_state) &&
+		   (myseq_diff >= 0) && (myseq_diff <= 2)) {
+		/* line down -> up */
+		lp->cisco_line_state = 1;
+		printk(KERN_WARNING
+		       "UPDOWN: Line protocol on Interface %s,"
+		       " changed state to up\n", lp->netdev->dev->name);
+		/* restart routing higher-level data across */
+	}
+
+	if (lp->cisco_debserint)
+		printk(KERN_DEBUG "%s: HDLC "
+		       "myseq %lu, mineseen %lu%c, yourseen %lu, %s\n",
+		       lp->netdev->dev->name, last_cisco_myseq, lp->cisco_mineseen,
+		       ((last_cisco_myseq == lp->cisco_mineseen) ? '*' : 040),
+		       lp->cisco_yourseq,
+		       ((lp->cisco_line_state) ? "line up" : "line down"));
+
+	skb = isdn_net_ciscohdlck_alloc_skb(lp, 4 + 14);
+	if (!skb)
+		return;
+
+	p = skb_put(skb, 4 + 14);
+
+	/* cisco header */
+	*(u8 *)(p + 0) = CISCO_ADDR_UNICAST;
+	*(u8 *)(p + 1) = CISCO_CTRL;
+	*(__be16 *)(p + 2) = cpu_to_be16(CISCO_TYPE_SLARP);
+
+	/* slarp keepalive */
+	*(__be32 *)(p +  4) = cpu_to_be32(CISCO_SLARP_KEEPALIVE);
+	*(__be32 *)(p +  8) = cpu_to_be32(lp->cisco_myseq);
+	*(__be32 *)(p + 12) = cpu_to_be32(lp->cisco_yourseq);
+	*(__be16 *)(p + 16) = cpu_to_be16(0xffff); // reliability, always 0xffff
+	p += 18;
+
+	isdn_net_write_super(lp, skb);
+
+	lp->cisco_timer.expires = jiffies + lp->cisco_keepalive_period * HZ;
+
+	add_timer(&lp->cisco_timer);
+}
+
+static void
+isdn_net_ciscohdlck_slarp_send_request(isdn_net_local *lp)
+{
+	struct sk_buff *skb;
+	unsigned char *p;
+
+	skb = isdn_net_ciscohdlck_alloc_skb(lp, 4 + 14);
+	if (!skb)
+		return;
+
+	p = skb_put(skb, 4 + 14);
+
+	/* cisco header */
+	*(u8 *)(p + 0) = CISCO_ADDR_UNICAST;
+	*(u8 *)(p + 1) = CISCO_CTRL;
+	*(__be16 *)(p + 2) = cpu_to_be16(CISCO_TYPE_SLARP);
+
+	/* slarp request */
+	*(__be32 *)(p +  4) = cpu_to_be32(CISCO_SLARP_REQUEST);
+	*(__be32 *)(p +  8) = cpu_to_be32(0); // address
+	*(__be32 *)(p + 12) = cpu_to_be32(0); // netmask
+	*(__be16 *)(p + 16) = cpu_to_be16(0); // unused
+	p += 18;
+
+	isdn_net_write_super(lp, skb);
+}
+
+static void
+isdn_net_ciscohdlck_connected(isdn_net_local *lp)
+{
+	lp->cisco_myseq = 0;
+	lp->cisco_mineseen = 0;
+	lp->cisco_yourseq = 0;
+	lp->cisco_keepalive_period = ISDN_TIMER_KEEPINT;
+	lp->cisco_last_slarp_in = 0;
+	lp->cisco_line_state = 0;
+	lp->cisco_debserint = 0;
+
+	/* send slarp request because interface/seq.no.s reset */
+	isdn_net_ciscohdlck_slarp_send_request(lp);
+
+	timer_setup(&lp->cisco_timer,
+		    isdn_net_ciscohdlck_slarp_send_keepalive, 0);
+	lp->cisco_timer.expires = jiffies + lp->cisco_keepalive_period * HZ;
+	add_timer(&lp->cisco_timer);
+}
+
+static void
+isdn_net_ciscohdlck_disconnected(isdn_net_local *lp)
+{
+	del_timer(&lp->cisco_timer);
+}
+
+static void
+isdn_net_ciscohdlck_slarp_send_reply(isdn_net_local *lp)
+{
+	struct sk_buff *skb;
+	unsigned char *p;
+	struct in_device *in_dev = NULL;
+	__be32 addr = 0;		/* local ipv4 address */
+	__be32 mask = 0;		/* local netmask */
+
+	if ((in_dev = lp->netdev->dev->ip_ptr) != NULL) {
+		/* take primary(first) address of interface */
+		struct in_ifaddr *ifa = in_dev->ifa_list;
+		if (ifa != NULL) {
+			addr = ifa->ifa_local;
+			mask = ifa->ifa_mask;
+		}
+	}
+
+	skb = isdn_net_ciscohdlck_alloc_skb(lp, 4 + 14);
+	if (!skb)
+		return;
+
+	p = skb_put(skb, 4 + 14);
+
+	/* cisco header */
+	*(u8 *)(p + 0) = CISCO_ADDR_UNICAST;
+	*(u8 *)(p + 1) = CISCO_CTRL;
+	*(__be16 *)(p + 2) = cpu_to_be16(CISCO_TYPE_SLARP);
+
+	/* slarp reply, send own ip/netmask; if values are nonsense remote
+	 * should think we are unable to provide it with an address via SLARP */
+	*(__be32 *)(p +  4) = cpu_to_be32(CISCO_SLARP_REPLY);
+	*(__be32 *)(p +  8) = addr; // address
+	*(__be32 *)(p + 12) = mask; // netmask
+	*(__be16 *)(p + 16) = cpu_to_be16(0); // unused
+	p += 18;
+
+	isdn_net_write_super(lp, skb);
+}
+
+static void
+isdn_net_ciscohdlck_slarp_in(isdn_net_local *lp, struct sk_buff *skb)
+{
+	unsigned char *p;
+	int period;
+	u32 code;
+	u32 my_seq;
+	u32 your_seq;
+	__be32 local;
+	__be32 *addr, *mask;
+
+	if (skb->len < 14)
+		return;
+
+	p = skb->data;
+	code = be32_to_cpup((__be32 *)p);
+	p += 4;
+
+	switch (code) {
+	case CISCO_SLARP_REQUEST:
+		lp->cisco_yourseq = 0;
+		isdn_net_ciscohdlck_slarp_send_reply(lp);
+		break;
+	case CISCO_SLARP_REPLY:
+		addr = (__be32 *)p;
+		mask = (__be32 *)(p + 4);
+		if (*mask != cpu_to_be32(0xfffffffc))
+			goto slarp_reply_out;
+		if ((*addr & cpu_to_be32(3)) == cpu_to_be32(0) ||
+		    (*addr & cpu_to_be32(3)) == cpu_to_be32(3))
+			goto slarp_reply_out;
+		local = *addr ^ cpu_to_be32(3);
+		printk(KERN_INFO "%s: got slarp reply: remote ip: %pI4, local ip: %pI4 mask: %pI4\n",
+		       lp->netdev->dev->name, addr, &local, mask);
+		break;
+	slarp_reply_out:
+		printk(KERN_INFO "%s: got invalid slarp reply (%pI4/%pI4) - ignored\n",
+		       lp->netdev->dev->name, addr, mask);
+		break;
+	case CISCO_SLARP_KEEPALIVE:
+		period = (int)((jiffies - lp->cisco_last_slarp_in
+				+ HZ / 2 - 1) / HZ);
+		if (lp->cisco_debserint &&
+		    (period != lp->cisco_keepalive_period) &&
+		    lp->cisco_last_slarp_in) {
+			printk(KERN_DEBUG "%s: Keepalive period mismatch - "
+			       "is %d but should be %d.\n",
+			       lp->netdev->dev->name, period,
+			       lp->cisco_keepalive_period);
+		}
+		lp->cisco_last_slarp_in = jiffies;
+		my_seq = be32_to_cpup((__be32 *)(p + 0));
+		your_seq = be32_to_cpup((__be32 *)(p + 4));
+		p += 10;
+		lp->cisco_yourseq = my_seq;
+		lp->cisco_mineseen = your_seq;
+		break;
+	}
+}
+
+static void
+isdn_net_ciscohdlck_receive(isdn_net_local *lp, struct sk_buff *skb)
+{
+	unsigned char *p;
+	u8 addr;
+	u8 ctrl;
+	u16 type;
+
+	if (skb->len < 4)
+		goto out_free;
+
+	p = skb->data;
+	addr = *(u8 *)(p + 0);
+	ctrl = *(u8 *)(p + 1);
+	type = be16_to_cpup((__be16 *)(p + 2));
+	p += 4;
+	skb_pull(skb, 4);
+
+	if (addr != CISCO_ADDR_UNICAST && addr != CISCO_ADDR_BROADCAST) {
+		printk(KERN_WARNING "%s: Unknown Cisco addr 0x%02x\n",
+		       lp->netdev->dev->name, addr);
+		goto out_free;
+	}
+	if (ctrl != CISCO_CTRL) {
+		printk(KERN_WARNING "%s: Unknown Cisco ctrl 0x%02x\n",
+		       lp->netdev->dev->name, ctrl);
+		goto out_free;
+	}
+
+	switch (type) {
+	case CISCO_TYPE_SLARP:
+		isdn_net_ciscohdlck_slarp_in(lp, skb);
+		goto out_free;
+	case CISCO_TYPE_CDP:
+		if (lp->cisco_debserint)
+			printk(KERN_DEBUG "%s: Received CDP packet. use "
+			       "\"no cdp enable\" on cisco.\n",
+			       lp->netdev->dev->name);
+		goto out_free;
+	default:
+		/* no special cisco protocol */
+		skb->protocol = htons(type);
+		netif_rx(skb);
+		return;
+	}
+
+out_free:
+	kfree_skb(skb);
+}
+
+/*
+ * Got a packet from ISDN-Channel.
+ */
+static void
+isdn_net_receive(struct net_device *ndev, struct sk_buff *skb)
+{
+	isdn_net_local *lp = netdev_priv(ndev);
+	isdn_net_local *olp = lp;	/* original 'lp' */
+#ifdef CONFIG_ISDN_X25
+	struct concap_proto *cprot = lp->netdev->cprot;
+#endif
+	lp->transcount += skb->len;
+
+	lp->stats.rx_packets++;
+	lp->stats.rx_bytes += skb->len;
+	if (lp->master) {
+		/* Bundling: If device is a slave-device, deliver to master, also
+		 * handle master's statistics and hangup-timeout
+		 */
+		ndev = lp->master;
+		lp = netdev_priv(ndev);
+		lp->stats.rx_packets++;
+		lp->stats.rx_bytes += skb->len;
+	}
+	skb->dev = ndev;
+	skb->pkt_type = PACKET_HOST;
+	skb_reset_mac_header(skb);
+#ifdef ISDN_DEBUG_NET_DUMP
+	isdn_dumppkt("R:", skb->data, skb->len, 40);
+#endif
+	switch (lp->p_encap) {
+	case ISDN_NET_ENCAP_ETHER:
+		/* Ethernet over ISDN */
+		olp->huptimer = 0;
+		lp->huptimer = 0;
+		skb->protocol = isdn_net_type_trans(skb, ndev);
+		break;
+	case ISDN_NET_ENCAP_UIHDLC:
+		/* HDLC with UI-frame (for ispa with -h1 option) */
+		olp->huptimer = 0;
+		lp->huptimer = 0;
+		skb_pull(skb, 2);
+		/* Fall through */
+	case ISDN_NET_ENCAP_RAWIP:
+		/* RAW-IP without MAC-Header */
+		olp->huptimer = 0;
+		lp->huptimer = 0;
+		skb->protocol = htons(ETH_P_IP);
+		break;
+	case ISDN_NET_ENCAP_CISCOHDLCK:
+		isdn_net_ciscohdlck_receive(lp, skb);
+		return;
+	case ISDN_NET_ENCAP_CISCOHDLC:
+		/* CISCO-HDLC IP with type field and  fake I-frame-header */
+		skb_pull(skb, 2);
+		/* Fall through */
+	case ISDN_NET_ENCAP_IPTYP:
+		/* IP with type field */
+		olp->huptimer = 0;
+		lp->huptimer = 0;
+		skb->protocol = *(__be16 *)&(skb->data[0]);
+		skb_pull(skb, 2);
+		if (*(unsigned short *) skb->data == 0xFFFF)
+			skb->protocol = htons(ETH_P_802_3);
+		break;
+#ifdef CONFIG_ISDN_PPP
+	case ISDN_NET_ENCAP_SYNCPPP:
+		/* huptimer is done in isdn_ppp_push_higher */
+		isdn_ppp_receive(lp->netdev, olp, skb);
+		return;
+#endif
+
+	default:
+#ifdef CONFIG_ISDN_X25
+		/* try if there are generic sync_device receiver routines */
+		if (cprot) if (cprot->pops)
+				   if (cprot->pops->data_ind) {
+					   cprot->pops->data_ind(cprot, skb);
+					   return;
+				   };
+#endif /* CONFIG_ISDN_X25 */
+		printk(KERN_WARNING "%s: unknown encapsulation, dropping\n",
+		       lp->netdev->dev->name);
+		kfree_skb(skb);
+		return;
+	}
+
+	netif_rx(skb);
+	return;
+}
+
+/*
+ * A packet arrived via ISDN. Search interface-chain for a corresponding
+ * interface. If found, deliver packet to receiver-function and return 1,
+ * else return 0.
+ */
+int
+isdn_net_rcv_skb(int idx, struct sk_buff *skb)
+{
+	isdn_net_dev *p = dev->rx_netdev[idx];
+
+	if (p) {
+		isdn_net_local *lp = p->local;
+		if ((lp->flags & ISDN_NET_CONNECTED) &&
+		    (!lp->dialstate)) {
+			isdn_net_receive(p->dev, skb);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/*
+ *  build an header
+ *  depends on encaps that is being used.
+ */
+
+static int isdn_net_header(struct sk_buff *skb, struct net_device *dev,
+			   unsigned short type,
+			   const void *daddr, const void *saddr, unsigned plen)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+	unsigned char *p;
+	int len = 0;
+
+	switch (lp->p_encap) {
+	case ISDN_NET_ENCAP_ETHER:
+		len = eth_header(skb, dev, type, daddr, saddr, plen);
+		break;
+#ifdef CONFIG_ISDN_PPP
+	case ISDN_NET_ENCAP_SYNCPPP:
+		/* stick on a fake header to keep fragmentation code happy. */
+		len = IPPP_MAX_HEADER;
+		skb_push(skb, len);
+		break;
+#endif
+	case ISDN_NET_ENCAP_RAWIP:
+		printk(KERN_WARNING "isdn_net_header called with RAW_IP!\n");
+		len = 0;
+		break;
+	case ISDN_NET_ENCAP_IPTYP:
+		/* ethernet type field */
+		*((__be16 *)skb_push(skb, 2)) = htons(type);
+		len = 2;
+		break;
+	case ISDN_NET_ENCAP_UIHDLC:
+		/* HDLC with UI-Frames (for ispa with -h1 option) */
+		*((__be16 *)skb_push(skb, 2)) = htons(0x0103);
+		len = 2;
+		break;
+	case ISDN_NET_ENCAP_CISCOHDLC:
+	case ISDN_NET_ENCAP_CISCOHDLCK:
+		p = skb_push(skb, 4);
+		*(u8 *)(p + 0) = CISCO_ADDR_UNICAST;
+		*(u8 *)(p + 1) = CISCO_CTRL;
+		*(__be16 *)(p + 2) = cpu_to_be16(type);
+		p += 4;
+		len = 4;
+		break;
+#ifdef CONFIG_ISDN_X25
+	default:
+		/* try if there are generic concap protocol routines */
+		if (lp->netdev->cprot) {
+			printk(KERN_WARNING "isdn_net_header called with concap_proto!\n");
+			len = 0;
+			break;
+		}
+		break;
+#endif /* CONFIG_ISDN_X25 */
+	}
+	return len;
+}
+
+static int isdn_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
+			     __be16 type)
+{
+	const struct net_device *dev = neigh->dev;
+	isdn_net_local *lp = netdev_priv(dev);
+
+	if (lp->p_encap == ISDN_NET_ENCAP_ETHER)
+		return eth_header_cache(neigh, hh, type);
+	return -1;
+}
+
+static void isdn_header_cache_update(struct hh_cache *hh,
+				     const struct net_device *dev,
+				     const unsigned char *haddr)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+	if (lp->p_encap == ISDN_NET_ENCAP_ETHER)
+		eth_header_cache_update(hh, dev, haddr);
+}
+
+static const struct header_ops isdn_header_ops = {
+	.create = isdn_net_header,
+	.cache = isdn_header_cache,
+	.cache_update = isdn_header_cache_update,
+};
+
+/*
+ * Interface-setup. (just after registering a new interface)
+ */
+static int
+isdn_net_init(struct net_device *ndev)
+{
+	ushort max_hlhdr_len = 0;
+	int drvidx;
+
+	/*
+	 *  up till binding we ask the protocol layer to reserve as much
+	 *  as we might need for HL layer
+	 */
+
+	for (drvidx = 0; drvidx < ISDN_MAX_DRIVERS; drvidx++)
+		if (dev->drv[drvidx])
+			if (max_hlhdr_len < dev->drv[drvidx]->interface->hl_hdrlen)
+				max_hlhdr_len = dev->drv[drvidx]->interface->hl_hdrlen;
+
+	ndev->hard_header_len = ETH_HLEN + max_hlhdr_len;
+	return 0;
+}
+
+static void
+isdn_net_swapbind(int drvidx)
+{
+	isdn_net_dev *p;
+
+#ifdef ISDN_DEBUG_NET_ICALL
+	printk(KERN_DEBUG "n_fi: swapping ch of %d\n", drvidx);
+#endif
+	p = dev->netdev;
+	while (p) {
+		if (p->local->pre_device == drvidx)
+			switch (p->local->pre_channel) {
+			case 0:
+				p->local->pre_channel = 1;
+				break;
+			case 1:
+				p->local->pre_channel = 0;
+				break;
+			}
+		p = (isdn_net_dev *) p->next;
+	}
+}
+
+static void
+isdn_net_swap_usage(int i1, int i2)
+{
+	int u1 = dev->usage[i1] & ISDN_USAGE_EXCLUSIVE;
+	int u2 = dev->usage[i2] & ISDN_USAGE_EXCLUSIVE;
+
+#ifdef ISDN_DEBUG_NET_ICALL
+	printk(KERN_DEBUG "n_fi: usage of %d and %d\n", i1, i2);
+#endif
+	dev->usage[i1] &= ~ISDN_USAGE_EXCLUSIVE;
+	dev->usage[i1] |= u2;
+	dev->usage[i2] &= ~ISDN_USAGE_EXCLUSIVE;
+	dev->usage[i2] |= u1;
+	isdn_info_update();
+}
+
+/*
+ * An incoming call-request has arrived.
+ * Search the interface-chain for an appropriate interface.
+ * If found, connect the interface to the ISDN-channel and initiate
+ * D- and B-Channel-setup. If secure-flag is set, accept only
+ * configured phone-numbers. If callback-flag is set, initiate
+ * callback-dialing.
+ *
+ * Return-Value: 0 = No appropriate interface for this call.
+ *               1 = Call accepted
+ *               2 = Reject call, wait cbdelay, then call back
+ *               3 = Reject call
+ *               4 = Wait cbdelay, then call back
+ *               5 = No appropriate interface for this call,
+ *                   would eventually match if CID was longer.
+ */
+
+int
+isdn_net_find_icall(int di, int ch, int idx, setup_parm *setup)
+{
+	char *eaz;
+	int si1;
+	int si2;
+	int ematch;
+	int wret;
+	int swapped;
+	int sidx = 0;
+	u_long flags;
+	isdn_net_dev *p;
+	isdn_net_phone *n;
+	char nr[ISDN_MSNLEN];
+	char *my_eaz;
+
+	/* Search name in netdev-chain */
+	if (!setup->phone[0]) {
+		nr[0] = '0';
+		nr[1] = '\0';
+		printk(KERN_INFO "isdn_net: Incoming call without OAD, assuming '0'\n");
+	} else
+		strlcpy(nr, setup->phone, ISDN_MSNLEN);
+	si1 = (int) setup->si1;
+	si2 = (int) setup->si2;
+	if (!setup->eazmsn[0]) {
+		printk(KERN_WARNING "isdn_net: Incoming call without CPN, assuming '0'\n");
+		eaz = "0";
+	} else
+		eaz = setup->eazmsn;
+	if (dev->net_verbose > 1)
+		printk(KERN_INFO "isdn_net: call from %s,%d,%d -> %s\n", nr, si1, si2, eaz);
+	/* Accept DATA and VOICE calls at this stage
+	 * local eaz is checked later for allowed call types
+	 */
+	if ((si1 != 7) && (si1 != 1)) {
+		if (dev->net_verbose > 1)
+			printk(KERN_INFO "isdn_net: Service-Indicator not 1 or 7, ignored\n");
+		return 0;
+	}
+	n = (isdn_net_phone *) 0;
+	p = dev->netdev;
+	ematch = wret = swapped = 0;
+#ifdef ISDN_DEBUG_NET_ICALL
+	printk(KERN_DEBUG "n_fi: di=%d ch=%d idx=%d usg=%d\n", di, ch, idx,
+	       dev->usage[idx]);
+#endif
+	while (p) {
+		int matchret;
+		isdn_net_local *lp = p->local;
+
+		/* If last check has triggered as binding-swap, revert it */
+		switch (swapped) {
+		case 2:
+			isdn_net_swap_usage(idx, sidx);
+			/* fall through */
+		case 1:
+			isdn_net_swapbind(di);
+			break;
+		}
+		swapped = 0;
+		/* check acceptable call types for DOV */
+		my_eaz = isdn_map_eaz2msn(lp->msn, di);
+		if (si1 == 1) { /* it's a DOV call, check if we allow it */
+			if (*my_eaz == 'v' || *my_eaz == 'V' ||
+			    *my_eaz == 'b' || *my_eaz == 'B')
+				my_eaz++; /* skip to allow a match */
+			else
+				my_eaz = NULL; /* force non match */
+		} else { /* it's a DATA call, check if we allow it */
+			if (*my_eaz == 'b' || *my_eaz == 'B')
+				my_eaz++; /* skip to allow a match */
+		}
+		if (my_eaz)
+			matchret = isdn_msncmp(eaz, my_eaz);
+		else
+			matchret = 1;
+		if (!matchret)
+			ematch = 1;
+
+		/* Remember if more numbers eventually can match */
+		if (matchret > wret)
+			wret = matchret;
+#ifdef ISDN_DEBUG_NET_ICALL
+		printk(KERN_DEBUG "n_fi: if='%s', l.msn=%s, l.flags=%d, l.dstate=%d\n",
+		       p->dev->name, lp->msn, lp->flags, lp->dialstate);
+#endif
+		if ((!matchret) &&                                        /* EAZ is matching   */
+		    (((!(lp->flags & ISDN_NET_CONNECTED)) &&              /* but not connected */
+		      (USG_NONE(dev->usage[idx]))) ||                     /* and ch. unused or */
+		     ((((lp->dialstate == 4) || (lp->dialstate == 12)) && /* if dialing        */
+		       (!(lp->flags & ISDN_NET_CALLBACK)))                /* but no callback   */
+			     )))
+		{
+#ifdef ISDN_DEBUG_NET_ICALL
+			printk(KERN_DEBUG "n_fi: match1, pdev=%d pch=%d\n",
+			       lp->pre_device, lp->pre_channel);
+#endif
+			if (dev->usage[idx] & ISDN_USAGE_EXCLUSIVE) {
+				if ((lp->pre_channel != ch) ||
+				    (lp->pre_device != di)) {
+					/* Here we got a problem:
+					 * If using an ICN-Card, an incoming call is always signaled on
+					 * on the first channel of the card, if both channels are
+					 * down. However this channel may be bound exclusive. If the
+					 * second channel is free, this call should be accepted.
+					 * The solution is horribly but it runs, so what:
+					 * We exchange the exclusive bindings of the two channels, the
+					 * corresponding variables in the interface-structs.
+					 */
+					if (ch == 0) {
+						sidx = isdn_dc2minor(di, 1);
+#ifdef ISDN_DEBUG_NET_ICALL
+						printk(KERN_DEBUG "n_fi: ch is 0\n");
+#endif
+						if (USG_NONE(dev->usage[sidx])) {
+							/* Second Channel is free, now see if it is bound
+							 * exclusive too. */
+							if (dev->usage[sidx] & ISDN_USAGE_EXCLUSIVE) {
+#ifdef ISDN_DEBUG_NET_ICALL
+								printk(KERN_DEBUG "n_fi: 2nd channel is down and bound\n");
+#endif
+								/* Yes, swap bindings only, if the original
+								 * binding is bound to channel 1 of this driver */
+								if ((lp->pre_device == di) &&
+								    (lp->pre_channel == 1)) {
+									isdn_net_swapbind(di);
+									swapped = 1;
+								} else {
+									/* ... else iterate next device */
+									p = (isdn_net_dev *) p->next;
+									continue;
+								}
+							} else {
+#ifdef ISDN_DEBUG_NET_ICALL
+								printk(KERN_DEBUG "n_fi: 2nd channel is down and unbound\n");
+#endif
+								/* No, swap always and swap excl-usage also */
+								isdn_net_swap_usage(idx, sidx);
+								isdn_net_swapbind(di);
+								swapped = 2;
+							}
+							/* Now check for exclusive binding again */
+#ifdef ISDN_DEBUG_NET_ICALL
+							printk(KERN_DEBUG "n_fi: final check\n");
+#endif
+							if ((dev->usage[idx] & ISDN_USAGE_EXCLUSIVE) &&
+							    ((lp->pre_channel != ch) ||
+							     (lp->pre_device != di))) {
+#ifdef ISDN_DEBUG_NET_ICALL
+								printk(KERN_DEBUG "n_fi: final check failed\n");
+#endif
+								p = (isdn_net_dev *) p->next;
+								continue;
+							}
+						}
+					} else {
+						/* We are already on the second channel, so nothing to do */
+#ifdef ISDN_DEBUG_NET_ICALL
+						printk(KERN_DEBUG "n_fi: already on 2nd channel\n");
+#endif
+					}
+				}
+			}
+#ifdef ISDN_DEBUG_NET_ICALL
+			printk(KERN_DEBUG "n_fi: match2\n");
+#endif
+			n = lp->phone[0];
+			if (lp->flags & ISDN_NET_SECURE) {
+				while (n) {
+					if (!isdn_msncmp(nr, n->num))
+						break;
+					n = (isdn_net_phone *) n->next;
+				}
+			}
+			if (n || (!(lp->flags & ISDN_NET_SECURE))) {
+#ifdef ISDN_DEBUG_NET_ICALL
+				printk(KERN_DEBUG "n_fi: match3\n");
+#endif
+				/* matching interface found */
+
+				/*
+				 * Is the state STOPPED?
+				 * If so, no dialin is allowed,
+				 * so reject actively.
+				 * */
+				if (ISDN_NET_DIALMODE(*lp) == ISDN_NET_DM_OFF) {
+					printk(KERN_INFO "incoming call, interface %s `stopped' -> rejected\n",
+					       p->dev->name);
+					return 3;
+				}
+				/*
+				 * Is the interface up?
+				 * If not, reject the call actively.
+				 */
+				if (!isdn_net_device_started(p)) {
+					printk(KERN_INFO "%s: incoming call, interface down -> rejected\n",
+					       p->dev->name);
+					return 3;
+				}
+				/* Interface is up, now see if it's a slave. If so, see if
+				 * it's master and parent slave is online. If not, reject the call.
+				 */
+				if (lp->master) {
+					isdn_net_local *mlp = ISDN_MASTER_PRIV(lp);
+					printk(KERN_DEBUG "ICALLslv: %s\n", p->dev->name);
+					printk(KERN_DEBUG "master=%s\n", lp->master->name);
+					if (mlp->flags & ISDN_NET_CONNECTED) {
+						printk(KERN_DEBUG "master online\n");
+						/* Master is online, find parent-slave (master if first slave) */
+						while (mlp->slave) {
+							if (ISDN_SLAVE_PRIV(mlp) == lp)
+								break;
+							mlp = ISDN_SLAVE_PRIV(mlp);
+						}
+					} else
+						printk(KERN_DEBUG "master offline\n");
+					/* Found parent, if it's offline iterate next device */
+					printk(KERN_DEBUG "mlpf: %d\n", mlp->flags & ISDN_NET_CONNECTED);
+					if (!(mlp->flags & ISDN_NET_CONNECTED)) {
+						p = (isdn_net_dev *) p->next;
+						continue;
+					}
+				}
+				if (lp->flags & ISDN_NET_CALLBACK) {
+					int chi;
+					/*
+					 * Is the state MANUAL?
+					 * If so, no callback can be made,
+					 * so reject actively.
+					 * */
+					if (ISDN_NET_DIALMODE(*lp) == ISDN_NET_DM_OFF) {
+						printk(KERN_INFO "incoming call for callback, interface %s `off' -> rejected\n",
+						       p->dev->name);
+						return 3;
+					}
+					printk(KERN_DEBUG "%s: call from %s -> %s, start callback\n",
+					       p->dev->name, nr, eaz);
+					if (lp->phone[1]) {
+						/* Grab a free ISDN-Channel */
+						spin_lock_irqsave(&dev->lock, flags);
+						if ((chi =
+						     isdn_get_free_channel(
+							     ISDN_USAGE_NET,
+							     lp->l2_proto,
+							     lp->l3_proto,
+							     lp->pre_device,
+							     lp->pre_channel,
+							     lp->msn)
+							    ) < 0) {
+
+							printk(KERN_WARNING "isdn_net_find_icall: No channel for %s\n",
+							       p->dev->name);
+							spin_unlock_irqrestore(&dev->lock, flags);
+							return 0;
+						}
+						/* Setup dialstate. */
+						lp->dtimer = 0;
+						lp->dialstate = 11;
+						/* Connect interface with channel */
+						isdn_net_bind_channel(lp, chi);
+#ifdef CONFIG_ISDN_PPP
+						if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+							if (isdn_ppp_bind(lp) < 0) {
+								spin_unlock_irqrestore(&dev->lock, flags);
+								isdn_net_unbind_channel(lp);
+								return 0;
+							}
+#endif
+						spin_unlock_irqrestore(&dev->lock, flags);
+						/* Initiate dialing by returning 2 or 4 */
+						return (lp->flags & ISDN_NET_CBHUP) ? 2 : 4;
+					} else
+						printk(KERN_WARNING "isdn_net: %s: No phone number\n",
+						       p->dev->name);
+					return 0;
+				} else {
+					printk(KERN_DEBUG "%s: call from %s -> %s accepted\n",
+					       p->dev->name, nr, eaz);
+					/* if this interface is dialing, it does it probably on a different
+					   device, so free this device */
+					if ((lp->dialstate == 4) || (lp->dialstate == 12)) {
+#ifdef CONFIG_ISDN_PPP
+						if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+							isdn_ppp_free(lp);
+#endif
+						isdn_net_lp_disconnected(lp);
+						isdn_free_channel(lp->isdn_device, lp->isdn_channel,
+								  ISDN_USAGE_NET);
+					}
+					spin_lock_irqsave(&dev->lock, flags);
+					dev->usage[idx] &= ISDN_USAGE_EXCLUSIVE;
+					dev->usage[idx] |= ISDN_USAGE_NET;
+					strcpy(dev->num[idx], nr);
+					isdn_info_update();
+					dev->st_netdev[idx] = lp->netdev;
+					lp->isdn_device = di;
+					lp->isdn_channel = ch;
+					lp->ppp_slot = -1;
+					lp->flags |= ISDN_NET_CONNECTED;
+					lp->dialstate = 7;
+					lp->dtimer = 0;
+					lp->outgoing = 0;
+					lp->huptimer = 0;
+					lp->hupflags |= ISDN_WAITCHARGE;
+					lp->hupflags &= ~ISDN_HAVECHARGE;
+#ifdef CONFIG_ISDN_PPP
+					if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP) {
+						if (isdn_ppp_bind(lp) < 0) {
+							isdn_net_unbind_channel(lp);
+							spin_unlock_irqrestore(&dev->lock, flags);
+							return 0;
+						}
+					}
+#endif
+					spin_unlock_irqrestore(&dev->lock, flags);
+					return 1;
+				}
+			}
+		}
+		p = (isdn_net_dev *) p->next;
+	}
+	/* If none of configured EAZ/MSN matched and not verbose, be silent */
+	if (!ematch || dev->net_verbose)
+		printk(KERN_INFO "isdn_net: call from %s -> %d %s ignored\n", nr, di, eaz);
+	return (wret == 2) ? 5 : 0;
+}
+
+/*
+ * Search list of net-interfaces for an interface with given name.
+ */
+isdn_net_dev *
+isdn_net_findif(char *name)
+{
+	isdn_net_dev *p = dev->netdev;
+
+	while (p) {
+		if (!strcmp(p->dev->name, name))
+			return p;
+		p = (isdn_net_dev *) p->next;
+	}
+	return (isdn_net_dev *) NULL;
+}
+
+/*
+ * Force a net-interface to dial out.
+ * This is called from the userlevel-routine below or
+ * from isdn_net_start_xmit().
+ */
+static int
+isdn_net_force_dial_lp(isdn_net_local *lp)
+{
+	if ((!(lp->flags & ISDN_NET_CONNECTED)) && !lp->dialstate) {
+		int chi;
+		if (lp->phone[1]) {
+			ulong flags;
+
+			/* Grab a free ISDN-Channel */
+			spin_lock_irqsave(&dev->lock, flags);
+			if ((chi = isdn_get_free_channel(
+				     ISDN_USAGE_NET,
+				     lp->l2_proto,
+				     lp->l3_proto,
+				     lp->pre_device,
+				     lp->pre_channel,
+				     lp->msn)) < 0) {
+				printk(KERN_WARNING "isdn_net_force_dial: No channel for %s\n",
+				       lp->netdev->dev->name);
+				spin_unlock_irqrestore(&dev->lock, flags);
+				return -EAGAIN;
+			}
+			lp->dialstate = 1;
+			/* Connect interface with channel */
+			isdn_net_bind_channel(lp, chi);
+#ifdef CONFIG_ISDN_PPP
+			if (lp->p_encap == ISDN_NET_ENCAP_SYNCPPP)
+				if (isdn_ppp_bind(lp) < 0) {
+					isdn_net_unbind_channel(lp);
+					spin_unlock_irqrestore(&dev->lock, flags);
+					return -EAGAIN;
+				}
+#endif
+			/* Initiate dialing */
+			spin_unlock_irqrestore(&dev->lock, flags);
+			isdn_net_dial();
+			return 0;
+		} else
+			return -EINVAL;
+	} else
+		return -EBUSY;
+}
+
+/*
+ * This is called from certain upper protocol layers (multilink ppp
+ * and x25iface encapsulation module) that want to initiate dialing
+ * themselves.
+ */
+int
+isdn_net_dial_req(isdn_net_local *lp)
+{
+	/* is there a better error code? */
+	if (!(ISDN_NET_DIALMODE(*lp) == ISDN_NET_DM_AUTO)) return -EBUSY;
+
+	return isdn_net_force_dial_lp(lp);
+}
+
+/*
+ * Force a net-interface to dial out.
+ * This is always called from within userspace (ISDN_IOCTL_NET_DIAL).
+ */
+int
+isdn_net_force_dial(char *name)
+{
+	isdn_net_dev *p = isdn_net_findif(name);
+
+	if (!p)
+		return -ENODEV;
+	return (isdn_net_force_dial_lp(p->local));
+}
+
+/* The ISDN-specific entries in the device structure. */
+static const struct net_device_ops isdn_netdev_ops = {
+	.ndo_init	      = isdn_net_init,
+	.ndo_open	      = isdn_net_open,
+	.ndo_stop	      = isdn_net_close,
+	.ndo_do_ioctl	      = isdn_net_ioctl,
+
+	.ndo_start_xmit	      = isdn_net_start_xmit,
+	.ndo_get_stats	      = isdn_net_get_stats,
+	.ndo_tx_timeout	      = isdn_net_tx_timeout,
+};
+
+/*
+ * Helper for alloc_netdev()
+ */
+static void _isdn_setup(struct net_device *dev)
+{
+	isdn_net_local *lp = netdev_priv(dev);
+
+	ether_setup(dev);
+
+	/* Setup the generic properties */
+	dev->flags = IFF_NOARP | IFF_POINTOPOINT;
+
+	/* isdn prepends a header in the tx path, can't share skbs */
+	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+	dev->header_ops = NULL;
+	dev->netdev_ops = &isdn_netdev_ops;
+
+	/* for clients with MPPP maybe higher values better */
+	dev->tx_queue_len = 30;
+
+	lp->p_encap = ISDN_NET_ENCAP_RAWIP;
+	lp->magic = ISDN_NET_MAGIC;
+	lp->last = lp;
+	lp->next = lp;
+	lp->isdn_device = -1;
+	lp->isdn_channel = -1;
+	lp->pre_device = -1;
+	lp->pre_channel = -1;
+	lp->exclusive = -1;
+	lp->ppp_slot = -1;
+	lp->pppbind = -1;
+	skb_queue_head_init(&lp->super_tx_queue);
+	lp->l2_proto = ISDN_PROTO_L2_X75I;
+	lp->l3_proto = ISDN_PROTO_L3_TRANS;
+	lp->triggercps = 6000;
+	lp->slavedelay = 10 * HZ;
+	lp->hupflags = ISDN_INHUP;	/* Do hangup even on incoming calls */
+	lp->onhtime = 10;	/* Default hangup-time for saving costs */
+	lp->dialmax = 1;
+	/* Hangup before Callback, manual dial */
+	lp->flags = ISDN_NET_CBHUP | ISDN_NET_DM_MANUAL;
+	lp->cbdelay = 25;	/* Wait 5 secs before Callback */
+	lp->dialtimeout = -1;  /* Infinite Dial-Timeout */
+	lp->dialwait = 5 * HZ; /* Wait 5 sec. after failed dial */
+	lp->dialstarted = 0;   /* Jiffies of last dial-start */
+	lp->dialwait_timer = 0;  /* Jiffies of earliest next dial-start */
+}
+
+/*
+ * Allocate a new network-interface and initialize its data structures.
+ */
+char *
+isdn_net_new(char *name, struct net_device *master)
+{
+	isdn_net_dev *netdev;
+
+	/* Avoid creating an existing interface */
+	if (isdn_net_findif(name)) {
+		printk(KERN_WARNING "isdn_net: interface %s already exists\n", name);
+		return NULL;
+	}
+	if (name == NULL)
+		return NULL;
+	if (!(netdev = kzalloc(sizeof(isdn_net_dev), GFP_KERNEL))) {
+		printk(KERN_WARNING "isdn_net: Could not allocate net-device\n");
+		return NULL;
+	}
+	netdev->dev = alloc_netdev(sizeof(isdn_net_local), name,
+				   NET_NAME_UNKNOWN, _isdn_setup);
+	if (!netdev->dev) {
+		printk(KERN_WARNING "isdn_net: Could not allocate network device\n");
+		kfree(netdev);
+		return NULL;
+	}
+	netdev->local = netdev_priv(netdev->dev);
+
+	if (master) {
+		/* Device shall be a slave */
+		struct net_device *p = MASTER_TO_SLAVE(master);
+		struct net_device *q = master;
+
+		netdev->local->master = master;
+		/* Put device at end of slave-chain */
+		while (p) {
+			q = p;
+			p = MASTER_TO_SLAVE(p);
+		}
+		MASTER_TO_SLAVE(q) = netdev->dev;
+	} else {
+		/* Device shall be a master */
+		/*
+		 * Watchdog timer (currently) for master only.
+		 */
+		netdev->dev->watchdog_timeo = ISDN_NET_TX_TIMEOUT;
+		if (register_netdev(netdev->dev) != 0) {
+			printk(KERN_WARNING "isdn_net: Could not register net-device\n");
+			free_netdev(netdev->dev);
+			kfree(netdev);
+			return NULL;
+		}
+	}
+	netdev->queue = netdev->local;
+	spin_lock_init(&netdev->queue_lock);
+
+	netdev->local->netdev = netdev;
+
+	INIT_WORK(&netdev->local->tqueue, isdn_net_softint);
+	spin_lock_init(&netdev->local->xmit_lock);
+
+	/* Put into to netdev-chain */
+	netdev->next = (void *) dev->netdev;
+	dev->netdev = netdev;
+	return netdev->dev->name;
+}
+
+char *
+isdn_net_newslave(char *parm)
+{
+	char *p = strchr(parm, ',');
+	isdn_net_dev *n;
+	char newname[10];
+
+	if (p) {
+		/* Slave-Name MUST not be empty or overflow 'newname' */
+		if (strscpy(newname, p + 1, sizeof(newname)) <= 0)
+			return NULL;
+		*p = 0;
+		/* Master must already exist */
+		if (!(n = isdn_net_findif(parm)))
+			return NULL;
+		/* Master must be a real interface, not a slave */
+		if (n->local->master)
+			return NULL;
+		/* Master must not be started yet */
+		if (isdn_net_device_started(n))
+			return NULL;
+		return (isdn_net_new(newname, n->dev));
+	}
+	return NULL;
+}
+
+/*
+ * Set interface-parameters.
+ * Always set all parameters, so the user-level application is responsible
+ * for not overwriting existing setups. It has to get the current
+ * setup first, if only selected parameters are to be changed.
+ */
+int
+isdn_net_setcfg(isdn_net_ioctl_cfg *cfg)
+{
+	isdn_net_dev *p = isdn_net_findif(cfg->name);
+	ulong features;
+	int i;
+	int drvidx;
+	int chidx;
+	char drvid[25];
+
+	if (p) {
+		isdn_net_local *lp = p->local;
+
+		/* See if any registered driver supports the features we want */
+		features = ((1 << cfg->l2_proto) << ISDN_FEATURE_L2_SHIFT) |
+			((1 << cfg->l3_proto) << ISDN_FEATURE_L3_SHIFT);
+		for (i = 0; i < ISDN_MAX_DRIVERS; i++)
+			if (dev->drv[i])
+				if ((dev->drv[i]->interface->features & features) == features)
+					break;
+		if (i == ISDN_MAX_DRIVERS) {
+			printk(KERN_WARNING "isdn_net: No driver with selected features\n");
+			return -ENODEV;
+		}
+		if (lp->p_encap != cfg->p_encap) {
+#ifdef CONFIG_ISDN_X25
+			struct concap_proto *cprot = p->cprot;
+#endif
+			if (isdn_net_device_started(p)) {
+				printk(KERN_WARNING "%s: cannot change encap when if is up\n",
+				       p->dev->name);
+				return -EBUSY;
+			}
+#ifdef CONFIG_ISDN_X25
+			if (cprot && cprot->pops)
+				cprot->pops->proto_del(cprot);
+			p->cprot = NULL;
+			lp->dops = NULL;
+			/* ... ,  prepare for configuration of new one ... */
+			switch (cfg->p_encap) {
+			case ISDN_NET_ENCAP_X25IFACE:
+				lp->dops = &isdn_concap_reliable_dl_dops;
+			}
+			/* ... and allocate new one ... */
+			p->cprot = isdn_concap_new(cfg->p_encap);
+			/* p -> cprot == NULL now if p_encap is not supported
+			   by means of the concap_proto mechanism */
+			/* the protocol is not configured yet; this will
+			   happen later when isdn_net_reset() is called */
+#endif
+		}
+		switch (cfg->p_encap) {
+		case ISDN_NET_ENCAP_SYNCPPP:
+#ifndef CONFIG_ISDN_PPP
+			printk(KERN_WARNING "%s: SyncPPP support not configured\n",
+			       p->dev->name);
+			return -EINVAL;
+#else
+			p->dev->type = ARPHRD_PPP;	/* change ARP type */
+			p->dev->addr_len = 0;
+#endif
+			break;
+		case ISDN_NET_ENCAP_X25IFACE:
+#ifndef CONFIG_ISDN_X25
+			printk(KERN_WARNING "%s: isdn-x25 support not configured\n",
+			       p->dev->name);
+			return -EINVAL;
+#else
+			p->dev->type = ARPHRD_X25;	/* change ARP type */
+			p->dev->addr_len = 0;
+#endif
+			break;
+		case ISDN_NET_ENCAP_CISCOHDLCK:
+			break;
+		default:
+			if (cfg->p_encap >= 0 &&
+			    cfg->p_encap <= ISDN_NET_ENCAP_MAX_ENCAP)
+				break;
+			printk(KERN_WARNING
+			       "%s: encapsulation protocol %d not supported\n",
+			       p->dev->name, cfg->p_encap);
+			return -EINVAL;
+		}
+		if (strlen(cfg->drvid)) {
+			/* A bind has been requested ... */
+			char *c,
+				*e;
+
+			if (strnlen(cfg->drvid, sizeof(cfg->drvid)) ==
+			    sizeof(cfg->drvid))
+				return -EINVAL;
+			drvidx = -1;
+			chidx = -1;
+			strcpy(drvid, cfg->drvid);
+			if ((c = strchr(drvid, ','))) {
+				/* The channel-number is appended to the driver-Id with a comma */
+				chidx = (int) simple_strtoul(c + 1, &e, 10);
+				if (e == c)
+					chidx = -1;
+				*c = '\0';
+			}
+			for (i = 0; i < ISDN_MAX_DRIVERS; i++)
+				/* Lookup driver-Id in array */
+				if (!(strcmp(dev->drvid[i], drvid))) {
+					drvidx = i;
+					break;
+				}
+			if ((drvidx == -1) || (chidx == -1))
+				/* Either driver-Id or channel-number invalid */
+				return -ENODEV;
+		} else {
+			/* Parameters are valid, so get them */
+			drvidx = lp->pre_device;
+			chidx = lp->pre_channel;
+		}
+		if (cfg->exclusive > 0) {
+			unsigned long flags;
+
+			/* If binding is exclusive, try to grab the channel */
+			spin_lock_irqsave(&dev->lock, flags);
+			if ((i = isdn_get_free_channel(ISDN_USAGE_NET,
+						       lp->l2_proto, lp->l3_proto, drvidx,
+						       chidx, lp->msn)) < 0) {
+				/* Grab failed, because desired channel is in use */
+				lp->exclusive = -1;
+				spin_unlock_irqrestore(&dev->lock, flags);
+				return -EBUSY;
+			}
+			/* All went ok, so update isdninfo */
+			dev->usage[i] = ISDN_USAGE_EXCLUSIVE;
+			isdn_info_update();
+			spin_unlock_irqrestore(&dev->lock, flags);
+			lp->exclusive = i;
+		} else {
+			/* Non-exclusive binding or unbind. */
+			lp->exclusive = -1;
+			if ((lp->pre_device != -1) && (cfg->exclusive == -1)) {
+				isdn_unexclusive_channel(lp->pre_device, lp->pre_channel);
+				isdn_free_channel(lp->pre_device, lp->pre_channel, ISDN_USAGE_NET);
+				drvidx = -1;
+				chidx = -1;
+			}
+		}
+		strlcpy(lp->msn, cfg->eaz, sizeof(lp->msn));
+		lp->pre_device = drvidx;
+		lp->pre_channel = chidx;
+		lp->onhtime = cfg->onhtime;
+		lp->charge = cfg->charge;
+		lp->l2_proto = cfg->l2_proto;
+		lp->l3_proto = cfg->l3_proto;
+		lp->cbdelay = cfg->cbdelay;
+		lp->dialmax = cfg->dialmax;
+		lp->triggercps = cfg->triggercps;
+		lp->slavedelay = cfg->slavedelay * HZ;
+		lp->pppbind = cfg->pppbind;
+		lp->dialtimeout = cfg->dialtimeout >= 0 ? cfg->dialtimeout * HZ : -1;
+		lp->dialwait = cfg->dialwait * HZ;
+		if (cfg->secure)
+			lp->flags |= ISDN_NET_SECURE;
+		else
+			lp->flags &= ~ISDN_NET_SECURE;
+		if (cfg->cbhup)
+			lp->flags |= ISDN_NET_CBHUP;
+		else
+			lp->flags &= ~ISDN_NET_CBHUP;
+		switch (cfg->callback) {
+		case 0:
+			lp->flags &= ~(ISDN_NET_CALLBACK | ISDN_NET_CBOUT);
+			break;
+		case 1:
+			lp->flags |= ISDN_NET_CALLBACK;
+			lp->flags &= ~ISDN_NET_CBOUT;
+			break;
+		case 2:
+			lp->flags |= ISDN_NET_CBOUT;
+			lp->flags &= ~ISDN_NET_CALLBACK;
+			break;
+		}
+		lp->flags &= ~ISDN_NET_DIALMODE_MASK;	/* first all bits off */
+		if (cfg->dialmode && !(cfg->dialmode & ISDN_NET_DIALMODE_MASK)) {
+			/* old isdnctrl version, where only 0 or 1 is given */
+			printk(KERN_WARNING
+			       "Old isdnctrl version detected! Please update.\n");
+			lp->flags |= ISDN_NET_DM_OFF; /* turn on `off' bit */
+		}
+		else {
+			lp->flags |= cfg->dialmode;  /* turn on selected bits */
+		}
+		if (cfg->chargehup)
+			lp->hupflags |= ISDN_CHARGEHUP;
+		else
+			lp->hupflags &= ~ISDN_CHARGEHUP;
+		if (cfg->ihup)
+			lp->hupflags |= ISDN_INHUP;
+		else
+			lp->hupflags &= ~ISDN_INHUP;
+		if (cfg->chargeint > 10) {
+			lp->hupflags |= ISDN_CHARGEHUP | ISDN_HAVECHARGE | ISDN_MANCHARGE;
+			lp->chargeint = cfg->chargeint * HZ;
+		}
+		if (cfg->p_encap != lp->p_encap) {
+			if (cfg->p_encap == ISDN_NET_ENCAP_RAWIP) {
+				p->dev->header_ops = NULL;
+				p->dev->flags = IFF_NOARP | IFF_POINTOPOINT;
+			} else {
+				p->dev->header_ops = &isdn_header_ops;
+				if (cfg->p_encap == ISDN_NET_ENCAP_ETHER)
+					p->dev->flags = IFF_BROADCAST | IFF_MULTICAST;
+				else
+					p->dev->flags = IFF_NOARP | IFF_POINTOPOINT;
+			}
+		}
+		lp->p_encap = cfg->p_encap;
+		return 0;
+	}
+	return -ENODEV;
+}
+
+/*
+ * Perform get-interface-parameters.ioctl
+ */
+int
+isdn_net_getcfg(isdn_net_ioctl_cfg *cfg)
+{
+	isdn_net_dev *p = isdn_net_findif(cfg->name);
+
+	if (p) {
+		isdn_net_local *lp = p->local;
+
+		strcpy(cfg->eaz, lp->msn);
+		cfg->exclusive = lp->exclusive;
+		if (lp->pre_device >= 0) {
+			sprintf(cfg->drvid, "%s,%d", dev->drvid[lp->pre_device],
+				lp->pre_channel);
+		} else
+			cfg->drvid[0] = '\0';
+		cfg->onhtime = lp->onhtime;
+		cfg->charge = lp->charge;
+		cfg->l2_proto = lp->l2_proto;
+		cfg->l3_proto = lp->l3_proto;
+		cfg->p_encap = lp->p_encap;
+		cfg->secure = (lp->flags & ISDN_NET_SECURE) ? 1 : 0;
+		cfg->callback = 0;
+		if (lp->flags & ISDN_NET_CALLBACK)
+			cfg->callback = 1;
+		if (lp->flags & ISDN_NET_CBOUT)
+			cfg->callback = 2;
+		cfg->cbhup = (lp->flags & ISDN_NET_CBHUP) ? 1 : 0;
+		cfg->dialmode = lp->flags & ISDN_NET_DIALMODE_MASK;
+		cfg->chargehup = (lp->hupflags & ISDN_CHARGEHUP) ? 1 : 0;
+		cfg->ihup = (lp->hupflags & ISDN_INHUP) ? 1 : 0;
+		cfg->cbdelay = lp->cbdelay;
+		cfg->dialmax = lp->dialmax;
+		cfg->triggercps = lp->triggercps;
+		cfg->slavedelay = lp->slavedelay / HZ;
+		cfg->chargeint = (lp->hupflags & ISDN_CHARGEHUP) ?
+			(lp->chargeint / HZ) : 0;
+		cfg->pppbind = lp->pppbind;
+		cfg->dialtimeout = lp->dialtimeout >= 0 ? lp->dialtimeout / HZ : -1;
+		cfg->dialwait = lp->dialwait / HZ;
+		if (lp->slave) {
+			if (strlen(lp->slave->name) >= 10)
+				strcpy(cfg->slave, "too-long");
+			else
+				strcpy(cfg->slave, lp->slave->name);
+		} else
+			cfg->slave[0] = '\0';
+		if (lp->master) {
+			if (strlen(lp->master->name) >= 10)
+				strcpy(cfg->master, "too-long");
+			else
+				strcpy(cfg->master, lp->master->name);
+		} else
+			cfg->master[0] = '\0';
+		return 0;
+	}
+	return -ENODEV;
+}
+
+/*
+ * Add a phone-number to an interface.
+ */
+int
+isdn_net_addphone(isdn_net_ioctl_phone *phone)
+{
+	isdn_net_dev *p = isdn_net_findif(phone->name);
+	isdn_net_phone *n;
+
+	if (p) {
+		if (!(n = kmalloc(sizeof(isdn_net_phone), GFP_KERNEL)))
+			return -ENOMEM;
+		strlcpy(n->num, phone->phone, sizeof(n->num));
+		n->next = p->local->phone[phone->outgoing & 1];
+		p->local->phone[phone->outgoing & 1] = n;
+		return 0;
+	}
+	return -ENODEV;
+}
+
+/*
+ * Copy a string of all phone-numbers of an interface to user space.
+ * This might sleep and must be called with the isdn semaphore down.
+ */
+int
+isdn_net_getphones(isdn_net_ioctl_phone *phone, char __user *phones)
+{
+	isdn_net_dev *p = isdn_net_findif(phone->name);
+	int inout = phone->outgoing & 1;
+	int more = 0;
+	int count = 0;
+	isdn_net_phone *n;
+
+	if (!p)
+		return -ENODEV;
+	inout &= 1;
+	for (n = p->local->phone[inout]; n; n = n->next) {
+		if (more) {
+			put_user(' ', phones++);
+			count++;
+		}
+		if (copy_to_user(phones, n->num, strlen(n->num) + 1)) {
+			return -EFAULT;
+		}
+		phones += strlen(n->num);
+		count += strlen(n->num);
+		more = 1;
+	}
+	put_user(0, phones);
+	count++;
+	return count;
+}
+
+/*
+ * Copy a string containing the peer's phone number of a connected interface
+ * to user space.
+ */
+int
+isdn_net_getpeer(isdn_net_ioctl_phone *phone, isdn_net_ioctl_phone __user *peer)
+{
+	isdn_net_dev *p = isdn_net_findif(phone->name);
+	int ch, dv, idx;
+
+	if (!p)
+		return -ENODEV;
+	/*
+	 * Theoretical race: while this executes, the remote number might
+	 * become invalid (hang up) or change (new connection), resulting
+	 * in (partially) wrong number copied to user. This race
+	 * currently ignored.
+	 */
+	ch = p->local->isdn_channel;
+	dv = p->local->isdn_device;
+	if (ch < 0 && dv < 0)
+		return -ENOTCONN;
+	idx = isdn_dc2minor(dv, ch);
+	if (idx < 0)
+		return -ENODEV;
+	/* for pre-bound channels, we need this extra check */
+	if (strncmp(dev->num[idx], "???", 3) == 0)
+		return -ENOTCONN;
+	strncpy(phone->phone, dev->num[idx], ISDN_MSNLEN);
+	phone->outgoing = USG_OUTGOING(dev->usage[idx]);
+	if (copy_to_user(peer, phone, sizeof(*peer)))
+		return -EFAULT;
+	return 0;
+}
+/*
+ * Delete a phone-number from an interface.
+ */
+int
+isdn_net_delphone(isdn_net_ioctl_phone *phone)
+{
+	isdn_net_dev *p = isdn_net_findif(phone->name);
+	int inout = phone->outgoing & 1;
+	isdn_net_phone *n;
+	isdn_net_phone *m;
+
+	if (p) {
+		n = p->local->phone[inout];
+		m = NULL;
+		while (n) {
+			if (!strcmp(n->num, phone->phone)) {
+				if (p->local->dial == n)
+					p->local->dial = n->next;
+				if (m)
+					m->next = n->next;
+				else
+					p->local->phone[inout] = n->next;
+				kfree(n);
+				return 0;
+			}
+			m = n;
+			n = (isdn_net_phone *) n->next;
+		}
+		return -EINVAL;
+	}
+	return -ENODEV;
+}
+
+/*
+ * Delete all phone-numbers of an interface.
+ */
+static int
+isdn_net_rmallphone(isdn_net_dev *p)
+{
+	isdn_net_phone *n;
+	isdn_net_phone *m;
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		n = p->local->phone[i];
+		while (n) {
+			m = n->next;
+			kfree(n);
+			n = m;
+		}
+		p->local->phone[i] = NULL;
+	}
+	p->local->dial = NULL;
+	return 0;
+}
+
+/*
+ * Force a hangup of a network-interface.
+ */
+int
+isdn_net_force_hangup(char *name)
+{
+	isdn_net_dev *p = isdn_net_findif(name);
+	struct net_device *q;
+
+	if (p) {
+		if (p->local->isdn_device < 0)
+			return 1;
+		q = p->local->slave;
+		/* If this interface has slaves, do a hangup for them also. */
+		while (q) {
+			isdn_net_hangup(q);
+			q = MASTER_TO_SLAVE(q);
+		}
+		isdn_net_hangup(p->dev);
+		return 0;
+	}
+	return -ENODEV;
+}
+
+/*
+ * Helper-function for isdn_net_rm: Do the real work.
+ */
+static int
+isdn_net_realrm(isdn_net_dev *p, isdn_net_dev *q)
+{
+	u_long flags;
+
+	if (isdn_net_device_started(p)) {
+		return -EBUSY;
+	}
+#ifdef CONFIG_ISDN_X25
+	if (p->cprot && p->cprot->pops)
+		p->cprot->pops->proto_del(p->cprot);
+#endif
+	/* Free all phone-entries */
+	isdn_net_rmallphone(p);
+	/* If interface is bound exclusive, free channel-usage */
+	if (p->local->exclusive != -1)
+		isdn_unexclusive_channel(p->local->pre_device, p->local->pre_channel);
+	if (p->local->master) {
+		/* It's a slave-device, so update master's slave-pointer if necessary */
+		if (((isdn_net_local *) ISDN_MASTER_PRIV(p->local))->slave ==
+		    p->dev)
+			((isdn_net_local *)ISDN_MASTER_PRIV(p->local))->slave =
+				p->local->slave;
+	} else {
+		/* Unregister only if it's a master-device */
+		unregister_netdev(p->dev);
+	}
+	/* Unlink device from chain */
+	spin_lock_irqsave(&dev->lock, flags);
+	if (q)
+		q->next = p->next;
+	else
+		dev->netdev = p->next;
+	if (p->local->slave) {
+		/* If this interface has a slave, remove it also */
+		char *slavename = p->local->slave->name;
+		isdn_net_dev *n = dev->netdev;
+		q = NULL;
+		while (n) {
+			if (!strcmp(n->dev->name, slavename)) {
+				spin_unlock_irqrestore(&dev->lock, flags);
+				isdn_net_realrm(n, q);
+				spin_lock_irqsave(&dev->lock, flags);
+				break;
+			}
+			q = n;
+			n = (isdn_net_dev *)n->next;
+		}
+	}
+	spin_unlock_irqrestore(&dev->lock, flags);
+	/* If no more net-devices remain, disable auto-hangup timer */
+	if (dev->netdev == NULL)
+		isdn_timer_ctrl(ISDN_TIMER_NETHANGUP, 0);
+	free_netdev(p->dev);
+	kfree(p);
+
+	return 0;
+}
+
+/*
+ * Remove a single network-interface.
+ */
+int
+isdn_net_rm(char *name)
+{
+	u_long flags;
+	isdn_net_dev *p;
+	isdn_net_dev *q;
+
+	/* Search name in netdev-chain */
+	spin_lock_irqsave(&dev->lock, flags);
+	p = dev->netdev;
+	q = NULL;
+	while (p) {
+		if (!strcmp(p->dev->name, name)) {
+			spin_unlock_irqrestore(&dev->lock, flags);
+			return (isdn_net_realrm(p, q));
+		}
+		q = p;
+		p = (isdn_net_dev *) p->next;
+	}
+	spin_unlock_irqrestore(&dev->lock, flags);
+	/* If no more net-devices remain, disable auto-hangup timer */
+	if (dev->netdev == NULL)
+		isdn_timer_ctrl(ISDN_TIMER_NETHANGUP, 0);
+	return -ENODEV;
+}
+
+/*
+ * Remove all network-interfaces
+ */
+int
+isdn_net_rmall(void)
+{
+	u_long flags;
+	int ret;
+
+	/* Walk through netdev-chain */
+	spin_lock_irqsave(&dev->lock, flags);
+	while (dev->netdev) {
+		if (!dev->netdev->local->master) {
+			/* Remove master-devices only, slaves get removed with their master */
+			spin_unlock_irqrestore(&dev->lock, flags);
+			if ((ret = isdn_net_realrm(dev->netdev, NULL))) {
+				return ret;
+			}
+			spin_lock_irqsave(&dev->lock, flags);
+		}
+	}
+	dev->netdev = NULL;
+	spin_unlock_irqrestore(&dev->lock, flags);
+	return 0;
+}