Adding upstream version 6.1.76.upstream/6.1.76

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

31 files changed, 15463 insertions, 0 deletions

diff --git a/drivers/isdn/mISDN/Kconfig b/drivers/isdn/mISDN/Kconfig
new file mode 100644
index 000000000..c9a53c222
--- /dev/null
+++ b/drivers/isdn/mISDN/Kconfig
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# modularer ISDN driver
+#
+
+menuconfig MISDN
+	tristate "Modular ISDN driver"
+	help
+	  Enable support for the modular ISDN driver.
+
+if MISDN != n
+
+config MISDN_DSP
+	tristate "Digital Audio Processing of transparent data"
+	depends on MISDN
+	select BITREVERSE
+	help
+	  Enable support for digital audio processing capability.
+
+	  This module may be used for special applications that require
+	  cross connecting of bchannels, conferencing, dtmf decoding,
+	  echo cancellation, tone generation, and Blowfish encryption and
+	  decryption. It may use hardware features if available.
+
+	  E.g. it is required for PBX4Linux. Go to http://isdn.eversberg.eu
+	  and get more information about this module and its usage.
+
+	  If unsure, say 'N'.
+
+config MISDN_L1OIP
+	tristate "ISDN over IP tunnel"
+	depends on MISDN
+	help
+	  Enable support for ISDN over IP tunnel.
+
+	  It features:
+	    - dynamic IP exchange, if one or both peers have dynamic IPs
+	    - BRI (S0) and PRI (S2M) interface
+	    - layer 1 control via network keepalive frames
+	    - direct tunneling of physical interface via IP
+
+	  NOTE: This protocol is called 'Layer 1 over IP' and is not
+	  compatible with ISDNoIP (Agfeo) or TDMoIP. Protocol description is
+	  provided in the source code.
+
+source "drivers/isdn/hardware/mISDN/Kconfig"
+
+endif #MISDN
diff --git a/drivers/isdn/mISDN/Makefile b/drivers/isdn/mISDN/Makefile
new file mode 100644
index 000000000..f3b4b7fa8
--- /dev/null
+++ b/drivers/isdn/mISDN/Makefile
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the modular ISDN driver
+#
+
+obj-$(CONFIG_MISDN) += mISDN_core.o
+obj-$(CONFIG_MISDN_DSP) += mISDN_dsp.o
+obj-$(CONFIG_MISDN_L1OIP) += l1oip.o
+
+# multi objects
+
+mISDN_core-objs := core.o fsm.o socket.o clock.o hwchannel.o stack.o layer1.o layer2.o tei.o timerdev.o
+mISDN_dsp-objs := dsp_core.o dsp_cmx.o dsp_tones.o dsp_dtmf.o dsp_audio.o dsp_blowfish.o dsp_pipeline.o dsp_hwec.o
+l1oip-objs := l1oip_core.o l1oip_codec.o
diff --git a/drivers/isdn/mISDN/clock.c b/drivers/isdn/mISDN/clock.c
new file mode 100644
index 000000000..01d878168
--- /dev/null
+++ b/drivers/isdn/mISDN/clock.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2008  by Andreas Eversberg <andreas@eversberg.eu>
+ *
+ * Quick API description:
+ *
+ * A clock source registers using mISDN_register_clock:
+ *	name = text string to name clock source
+ *	priority = value to priorize clock sources (0 = default)
+ *	ctl = callback function to enable/disable clock source
+ *	priv = private pointer of clock source
+ *	return = pointer to clock source structure;
+ *
+ * Note: Callback 'ctl' can be called before mISDN_register_clock returns!
+ *       Also it can be called during mISDN_unregister_clock.
+ *
+ * A clock source calls mISDN_clock_update with given samples elapsed, if
+ * enabled. If function call is delayed, tv must be set with the timestamp
+ * of the actual event.
+ *
+ * A clock source unregisters using mISDN_unregister_clock.
+ *
+ * To get current clock, call mISDN_clock_get. The signed short value
+ * counts the number of samples since. Time since last clock event is added.
+ */
+
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/ktime.h>
+#include <linux/mISDNif.h>
+#include <linux/export.h>
+#include "core.h"
+
+static u_int *debug;
+static LIST_HEAD(iclock_list);
+static DEFINE_RWLOCK(iclock_lock);
+static u16 iclock_count;		/* counter of last clock */
+static ktime_t iclock_timestamp;	/* time stamp of last clock */
+static int iclock_timestamp_valid;	/* already received one timestamp */
+static struct mISDNclock *iclock_current;
+
+void
+mISDN_init_clock(u_int *dp)
+{
+	debug = dp;
+	iclock_timestamp = ktime_get();
+}
+
+static void
+select_iclock(void)
+{
+	struct mISDNclock *iclock, *bestclock = NULL, *lastclock = NULL;
+	int pri = -128;
+
+	list_for_each_entry(iclock, &iclock_list, list) {
+		if (iclock->pri > pri) {
+			pri = iclock->pri;
+			bestclock = iclock;
+		}
+		if (iclock_current == iclock)
+			lastclock = iclock;
+	}
+	if (lastclock && bestclock != lastclock) {
+		/* last used clock source still exists but changes, disable */
+		if (*debug & DEBUG_CLOCK)
+			printk(KERN_DEBUG "Old clock source '%s' disable.\n",
+			       lastclock->name);
+		lastclock->ctl(lastclock->priv, 0);
+	}
+	if (bestclock && bestclock != iclock_current) {
+		/* new clock source selected, enable */
+		if (*debug & DEBUG_CLOCK)
+			printk(KERN_DEBUG "New clock source '%s' enable.\n",
+			       bestclock->name);
+		bestclock->ctl(bestclock->priv, 1);
+	}
+	if (bestclock != iclock_current) {
+		/* no clock received yet */
+		iclock_timestamp_valid = 0;
+	}
+	iclock_current = bestclock;
+}
+
+struct mISDNclock
+*mISDN_register_clock(char *name, int pri, clockctl_func_t *ctl, void *priv)
+{
+	u_long			flags;
+	struct mISDNclock	*iclock;
+
+	if (*debug & (DEBUG_CORE | DEBUG_CLOCK))
+		printk(KERN_DEBUG "%s: %s %d\n", __func__, name, pri);
+	iclock = kzalloc(sizeof(struct mISDNclock), GFP_ATOMIC);
+	if (!iclock) {
+		printk(KERN_ERR "%s: No memory for clock entry.\n", __func__);
+		return NULL;
+	}
+	strncpy(iclock->name, name, sizeof(iclock->name) - 1);
+	iclock->pri = pri;
+	iclock->priv = priv;
+	iclock->ctl = ctl;
+	write_lock_irqsave(&iclock_lock, flags);
+	list_add_tail(&iclock->list, &iclock_list);
+	select_iclock();
+	write_unlock_irqrestore(&iclock_lock, flags);
+	return iclock;
+}
+EXPORT_SYMBOL(mISDN_register_clock);
+
+void
+mISDN_unregister_clock(struct mISDNclock *iclock)
+{
+	u_long	flags;
+
+	if (*debug & (DEBUG_CORE | DEBUG_CLOCK))
+		printk(KERN_DEBUG "%s: %s %d\n", __func__, iclock->name,
+		       iclock->pri);
+	write_lock_irqsave(&iclock_lock, flags);
+	if (iclock_current == iclock) {
+		if (*debug & DEBUG_CLOCK)
+			printk(KERN_DEBUG
+			       "Current clock source '%s' unregisters.\n",
+			       iclock->name);
+		iclock->ctl(iclock->priv, 0);
+	}
+	list_del(&iclock->list);
+	select_iclock();
+	write_unlock_irqrestore(&iclock_lock, flags);
+}
+EXPORT_SYMBOL(mISDN_unregister_clock);
+
+void
+mISDN_clock_update(struct mISDNclock *iclock, int samples, ktime_t *timestamp)
+{
+	u_long		flags;
+	ktime_t		timestamp_now;
+	u16		delta;
+
+	write_lock_irqsave(&iclock_lock, flags);
+	if (iclock_current != iclock) {
+		printk(KERN_ERR "%s: '%s' sends us clock updates, but we do "
+		       "listen to '%s'. This is a bug!\n", __func__,
+		       iclock->name,
+		       iclock_current ? iclock_current->name : "nothing");
+		iclock->ctl(iclock->priv, 0);
+		write_unlock_irqrestore(&iclock_lock, flags);
+		return;
+	}
+	if (iclock_timestamp_valid) {
+		/* increment sample counter by given samples */
+		iclock_count += samples;
+		if (timestamp) { /* timestamp must be set, if function call is delayed */
+			iclock_timestamp = *timestamp;
+		} else	{
+			iclock_timestamp = ktime_get();
+		}
+	} else {
+		/* calc elapsed time by system clock */
+		if (timestamp) { /* timestamp must be set, if function call is delayed */
+			timestamp_now = *timestamp;
+		} else {
+			timestamp_now = ktime_get();
+		}
+		delta = ktime_divns(ktime_sub(timestamp_now, iclock_timestamp),
+				(NSEC_PER_SEC / 8000));
+		/* add elapsed time to counter and set new timestamp */
+		iclock_count += delta;
+		iclock_timestamp = timestamp_now;
+		iclock_timestamp_valid = 1;
+		if (*debug & DEBUG_CLOCK)
+			printk("Received first clock from source '%s'.\n",
+			       iclock_current ? iclock_current->name : "nothing");
+	}
+	write_unlock_irqrestore(&iclock_lock, flags);
+}
+EXPORT_SYMBOL(mISDN_clock_update);
+
+unsigned short
+mISDN_clock_get(void)
+{
+	u_long		flags;
+	ktime_t		timestamp_now;
+	u16		delta;
+	u16		count;
+
+	read_lock_irqsave(&iclock_lock, flags);
+	/* calc elapsed time by system clock */
+	timestamp_now = ktime_get();
+	delta = ktime_divns(ktime_sub(timestamp_now, iclock_timestamp),
+			(NSEC_PER_SEC / 8000));
+	/* add elapsed time to counter */
+	count =	iclock_count + delta;
+	read_unlock_irqrestore(&iclock_lock, flags);
+	return count;
+}
+EXPORT_SYMBOL(mISDN_clock_get);
diff --git a/drivers/isdn/mISDN/core.c b/drivers/isdn/mISDN/core.c
new file mode 100644
index 000000000..90ee56d07
--- /dev/null
+++ b/drivers/isdn/mISDN/core.c
@@ -0,0 +1,420 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/mISDNif.h>
+#include "core.h"
+
+static u_int debug;
+
+MODULE_AUTHOR("Karsten Keil");
+MODULE_LICENSE("GPL");
+module_param(debug, uint, S_IRUGO | S_IWUSR);
+
+static u64		device_ids;
+#define MAX_DEVICE_ID	63
+
+static LIST_HEAD(Bprotocols);
+static DEFINE_RWLOCK(bp_lock);
+
+static void mISDN_dev_release(struct device *dev)
+{
+	/* nothing to do: the device is part of its parent's data structure */
+}
+
+static ssize_t id_show(struct device *dev,
+		       struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return -ENODEV;
+	return sprintf(buf, "%d\n", mdev->id);
+}
+static DEVICE_ATTR_RO(id);
+
+static ssize_t nrbchan_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return -ENODEV;
+	return sprintf(buf, "%d\n", mdev->nrbchan);
+}
+static DEVICE_ATTR_RO(nrbchan);
+
+static ssize_t d_protocols_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return -ENODEV;
+	return sprintf(buf, "%d\n", mdev->Dprotocols);
+}
+static DEVICE_ATTR_RO(d_protocols);
+
+static ssize_t b_protocols_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return -ENODEV;
+	return sprintf(buf, "%d\n", mdev->Bprotocols | get_all_Bprotocols());
+}
+static DEVICE_ATTR_RO(b_protocols);
+
+static ssize_t protocol_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return -ENODEV;
+	return sprintf(buf, "%d\n", mdev->D.protocol);
+}
+static DEVICE_ATTR_RO(protocol);
+
+static ssize_t name_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	strcpy(buf, dev_name(dev));
+	return strlen(buf);
+}
+static DEVICE_ATTR_RO(name);
+
+#if 0 /* hangs */
+static ssize_t name_set(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	int err = 0;
+	char *out = kmalloc(count + 1, GFP_KERNEL);
+
+	if (!out)
+		return -ENOMEM;
+
+	memcpy(out, buf, count);
+	if (count && out[count - 1] == '\n')
+		out[--count] = 0;
+	if (count)
+		err = device_rename(dev, out);
+	kfree(out);
+
+	return (err < 0) ? err : count;
+}
+static DEVICE_ATTR_RW(name);
+#endif
+
+static ssize_t channelmap_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+	char *bp = buf;
+	int i;
+
+	for (i = 0; i <= mdev->nrbchan; i++)
+		*bp++ = test_channelmap(i, mdev->channelmap) ? '1' : '0';
+
+	return bp - buf;
+}
+static DEVICE_ATTR_RO(channelmap);
+
+static struct attribute *mISDN_attrs[] = {
+	&dev_attr_id.attr,
+	&dev_attr_d_protocols.attr,
+	&dev_attr_b_protocols.attr,
+	&dev_attr_protocol.attr,
+	&dev_attr_channelmap.attr,
+	&dev_attr_nrbchan.attr,
+	&dev_attr_name.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(mISDN);
+
+static int mISDN_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return 0;
+
+	if (add_uevent_var(env, "nchans=%d", mdev->nrbchan))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void mISDN_class_release(struct class *cls)
+{
+	/* do nothing, it's static */
+}
+
+static struct class mISDN_class = {
+	.name = "mISDN",
+	.owner = THIS_MODULE,
+	.dev_uevent = mISDN_uevent,
+	.dev_groups = mISDN_groups,
+	.dev_release = mISDN_dev_release,
+	.class_release = mISDN_class_release,
+};
+
+static int
+_get_mdevice(struct device *dev, const void *id)
+{
+	struct mISDNdevice *mdev = dev_to_mISDN(dev);
+
+	if (!mdev)
+		return 0;
+	if (mdev->id != *(const u_int *)id)
+		return 0;
+	return 1;
+}
+
+struct mISDNdevice
+*get_mdevice(u_int id)
+{
+	return dev_to_mISDN(class_find_device(&mISDN_class, NULL, &id,
+					      _get_mdevice));
+}
+
+static int
+_get_mdevice_count(struct device *dev, void *cnt)
+{
+	*(int *)cnt += 1;
+	return 0;
+}
+
+int
+get_mdevice_count(void)
+{
+	int cnt = 0;
+
+	class_for_each_device(&mISDN_class, NULL, &cnt, _get_mdevice_count);
+	return cnt;
+}
+
+static int
+get_free_devid(void)
+{
+	u_int	i;
+
+	for (i = 0; i <= MAX_DEVICE_ID; i++)
+		if (!test_and_set_bit(i, (u_long *)&device_ids))
+			break;
+	if (i > MAX_DEVICE_ID)
+		return -EBUSY;
+	return i;
+}
+
+int
+mISDN_register_device(struct mISDNdevice *dev,
+		      struct device *parent, char *name)
+{
+	int	err;
+
+	err = get_free_devid();
+	if (err < 0)
+		return err;
+	dev->id = err;
+
+	device_initialize(&dev->dev);
+	if (name && name[0])
+		dev_set_name(&dev->dev, "%s", name);
+	else
+		dev_set_name(&dev->dev, "mISDN%d", dev->id);
+	if (debug & DEBUG_CORE)
+		printk(KERN_DEBUG "mISDN_register %s %d\n",
+		       dev_name(&dev->dev), dev->id);
+	dev->dev.class = &mISDN_class;
+
+	err = create_stack(dev);
+	if (err)
+		goto error1;
+
+	dev->dev.platform_data = dev;
+	dev->dev.parent = parent;
+	dev_set_drvdata(&dev->dev, dev);
+
+	err = device_add(&dev->dev);
+	if (err)
+		goto error3;
+	return 0;
+
+error3:
+	delete_stack(dev);
+error1:
+	put_device(&dev->dev);
+	return err;
+
+}
+EXPORT_SYMBOL(mISDN_register_device);
+
+void
+mISDN_unregister_device(struct mISDNdevice *dev) {
+	if (debug & DEBUG_CORE)
+		printk(KERN_DEBUG "mISDN_unregister %s %d\n",
+		       dev_name(&dev->dev), dev->id);
+	/* sysfs_remove_link(&dev->dev.kobj, "device"); */
+	device_del(&dev->dev);
+	dev_set_drvdata(&dev->dev, NULL);
+
+	test_and_clear_bit(dev->id, (u_long *)&device_ids);
+	delete_stack(dev);
+	put_device(&dev->dev);
+}
+EXPORT_SYMBOL(mISDN_unregister_device);
+
+u_int
+get_all_Bprotocols(void)
+{
+	struct Bprotocol	*bp;
+	u_int	m = 0;
+
+	read_lock(&bp_lock);
+	list_for_each_entry(bp, &Bprotocols, list)
+		m |= bp->Bprotocols;
+	read_unlock(&bp_lock);
+	return m;
+}
+
+struct Bprotocol *
+get_Bprotocol4mask(u_int m)
+{
+	struct Bprotocol	*bp;
+
+	read_lock(&bp_lock);
+	list_for_each_entry(bp, &Bprotocols, list)
+		if (bp->Bprotocols & m) {
+			read_unlock(&bp_lock);
+			return bp;
+		}
+	read_unlock(&bp_lock);
+	return NULL;
+}
+
+struct Bprotocol *
+get_Bprotocol4id(u_int id)
+{
+	u_int	m;
+
+	if (id < ISDN_P_B_START || id > 63) {
+		printk(KERN_WARNING "%s id not in range  %d\n",
+		       __func__, id);
+		return NULL;
+	}
+	m = 1 << (id & ISDN_P_B_MASK);
+	return get_Bprotocol4mask(m);
+}
+
+int
+mISDN_register_Bprotocol(struct Bprotocol *bp)
+{
+	u_long			flags;
+	struct Bprotocol	*old;
+
+	if (debug & DEBUG_CORE)
+		printk(KERN_DEBUG "%s: %s/%x\n", __func__,
+		       bp->name, bp->Bprotocols);
+	old = get_Bprotocol4mask(bp->Bprotocols);
+	if (old) {
+		printk(KERN_WARNING
+		       "register duplicate protocol old %s/%x new %s/%x\n",
+		       old->name, old->Bprotocols, bp->name, bp->Bprotocols);
+		return -EBUSY;
+	}
+	write_lock_irqsave(&bp_lock, flags);
+	list_add_tail(&bp->list, &Bprotocols);
+	write_unlock_irqrestore(&bp_lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_register_Bprotocol);
+
+void
+mISDN_unregister_Bprotocol(struct Bprotocol *bp)
+{
+	u_long	flags;
+
+	if (debug & DEBUG_CORE)
+		printk(KERN_DEBUG "%s: %s/%x\n", __func__, bp->name,
+		       bp->Bprotocols);
+	write_lock_irqsave(&bp_lock, flags);
+	list_del(&bp->list);
+	write_unlock_irqrestore(&bp_lock, flags);
+}
+EXPORT_SYMBOL(mISDN_unregister_Bprotocol);
+
+static const char *msg_no_channel = "<no channel>";
+static const char *msg_no_stack = "<no stack>";
+static const char *msg_no_stackdev = "<no stack device>";
+
+const char *mISDNDevName4ch(struct mISDNchannel *ch)
+{
+	if (!ch)
+		return msg_no_channel;
+	if (!ch->st)
+		return msg_no_stack;
+	if (!ch->st->dev)
+		return msg_no_stackdev;
+	return dev_name(&ch->st->dev->dev);
+};
+EXPORT_SYMBOL(mISDNDevName4ch);
+
+static int
+mISDNInit(void)
+{
+	int	err;
+
+	printk(KERN_INFO "Modular ISDN core version %d.%d.%d\n",
+	       MISDN_MAJOR_VERSION, MISDN_MINOR_VERSION, MISDN_RELEASE);
+	mISDN_init_clock(&debug);
+	mISDN_initstack(&debug);
+	err = class_register(&mISDN_class);
+	if (err)
+		goto error1;
+	err = mISDN_inittimer(&debug);
+	if (err)
+		goto error2;
+	err = Isdnl1_Init(&debug);
+	if (err)
+		goto error3;
+	err = Isdnl2_Init(&debug);
+	if (err)
+		goto error4;
+	err = misdn_sock_init(&debug);
+	if (err)
+		goto error5;
+	return 0;
+
+error5:
+	Isdnl2_cleanup();
+error4:
+	Isdnl1_cleanup();
+error3:
+	mISDN_timer_cleanup();
+error2:
+	class_unregister(&mISDN_class);
+error1:
+	return err;
+}
+
+static void mISDN_cleanup(void)
+{
+	misdn_sock_cleanup();
+	Isdnl2_cleanup();
+	Isdnl1_cleanup();
+	mISDN_timer_cleanup();
+	class_unregister(&mISDN_class);
+
+	printk(KERN_DEBUG "mISDNcore unloaded\n");
+}
+
+module_init(mISDNInit);
+module_exit(mISDN_cleanup);
diff --git a/drivers/isdn/mISDN/core.h b/drivers/isdn/mISDN/core.h
new file mode 100644
index 000000000..42599f49c
--- /dev/null
+++ b/drivers/isdn/mISDN/core.h
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#ifndef mISDN_CORE_H
+#define mISDN_CORE_H
+
+extern struct mISDNdevice	*get_mdevice(u_int);
+extern int			get_mdevice_count(void);
+
+/* stack status flag */
+#define mISDN_STACK_ACTION_MASK		0x0000ffff
+#define mISDN_STACK_COMMAND_MASK	0x000f0000
+#define mISDN_STACK_STATUS_MASK		0xfff00000
+/* action bits 0-15 */
+#define mISDN_STACK_WORK	0
+#define mISDN_STACK_SETUP	1
+#define mISDN_STACK_CLEARING	2
+#define mISDN_STACK_RESTART	3
+#define mISDN_STACK_WAKEUP	4
+#define mISDN_STACK_ABORT	15
+/* command bits 16-19 */
+#define mISDN_STACK_STOPPED	16
+#define mISDN_STACK_INIT	17
+#define mISDN_STACK_THREADSTART	18
+/* status bits 20-31 */
+#define mISDN_STACK_BCHANNEL	20
+#define mISDN_STACK_ACTIVE      29
+#define mISDN_STACK_RUNNING     30
+#define mISDN_STACK_KILLED      31
+
+
+/* manager options */
+#define MGR_OPT_USER		24
+#define MGR_OPT_NETWORK		25
+
+extern int	connect_Bstack(struct mISDNdevice *, struct mISDNchannel *,
+			       u_int, struct sockaddr_mISDN *);
+extern int	connect_layer1(struct mISDNdevice *, struct mISDNchannel *,
+			       u_int, struct sockaddr_mISDN *);
+extern int	create_l2entity(struct mISDNdevice *, struct mISDNchannel *,
+				u_int, struct sockaddr_mISDN *);
+
+extern int	create_stack(struct mISDNdevice *);
+extern int	create_teimanager(struct mISDNdevice *);
+extern void	delete_teimanager(struct mISDNchannel *);
+extern void	delete_channel(struct mISDNchannel *);
+extern void	delete_stack(struct mISDNdevice *);
+extern void	mISDN_initstack(u_int *);
+extern int      misdn_sock_init(u_int *);
+extern void     misdn_sock_cleanup(void);
+extern void	add_layer2(struct mISDNchannel *, struct mISDNstack *);
+extern void	__add_layer2(struct mISDNchannel *, struct mISDNstack *);
+
+extern u_int		get_all_Bprotocols(void);
+struct Bprotocol	*get_Bprotocol4mask(u_int);
+struct Bprotocol	*get_Bprotocol4id(u_int);
+
+extern int	mISDN_inittimer(u_int *);
+extern void	mISDN_timer_cleanup(void);
+
+extern int	Isdnl1_Init(u_int *);
+extern void	Isdnl1_cleanup(void);
+extern int	Isdnl2_Init(u_int *);
+extern void	Isdnl2_cleanup(void);
+
+extern void	mISDN_init_clock(u_int *);
+
+#endif
diff --git a/drivers/isdn/mISDN/dsp.h b/drivers/isdn/mISDN/dsp.h
new file mode 100644
index 000000000..baf31258f
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp.h
@@ -0,0 +1,277 @@
+/*
+ * Audio support data for ISDN4Linux.
+ *
+ * Copyright 2002/2003 by Andreas Eversberg (jolly@eversberg.eu)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#define DEBUG_DSP_CTRL		0x0001
+#define DEBUG_DSP_CORE		0x0002
+#define DEBUG_DSP_DTMF		0x0004
+#define DEBUG_DSP_CMX		0x0010
+#define DEBUG_DSP_TONE		0x0020
+#define DEBUG_DSP_BLOWFISH	0x0040
+#define DEBUG_DSP_DELAY		0x0100
+#define DEBUG_DSP_CLOCK		0x0200
+#define DEBUG_DSP_DTMFCOEFF	0x8000 /* heavy output */
+
+/* options may be:
+ *
+ * bit 0 = use ulaw instead of alaw
+ * bit 1 = enable hfc hardware acceleration for all channels
+ *
+ */
+#define DSP_OPT_ULAW		(1 << 0)
+#define DSP_OPT_NOHARDWARE	(1 << 1)
+
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+#include "dsp_ecdis.h"
+
+extern int dsp_options;
+extern int dsp_debug;
+extern int dsp_poll;
+extern int dsp_tics;
+extern spinlock_t dsp_lock;
+extern struct work_struct dsp_workq;
+extern u32 dsp_poll_diff; /* calculated fix-comma corrected poll value */
+
+/***************
+ * audio stuff *
+ ***************/
+
+extern s32 dsp_audio_alaw_to_s32[256];
+extern s32 dsp_audio_ulaw_to_s32[256];
+extern s32 *dsp_audio_law_to_s32;
+extern u8 dsp_audio_s16_to_law[65536];
+extern u8 dsp_audio_alaw_to_ulaw[256];
+extern u8 dsp_audio_mix_law[65536];
+extern u8 dsp_audio_seven2law[128];
+extern u8 dsp_audio_law2seven[256];
+extern void dsp_audio_generate_law_tables(void);
+extern void dsp_audio_generate_s2law_table(void);
+extern void dsp_audio_generate_seven(void);
+extern void dsp_audio_generate_mix_table(void);
+extern void dsp_audio_generate_ulaw_samples(void);
+extern void dsp_audio_generate_volume_changes(void);
+extern u8 dsp_silence;
+
+
+/*************
+ * cmx stuff *
+ *************/
+
+#define MAX_POLL	256	/* maximum number of send-chunks */
+
+#define CMX_BUFF_SIZE	0x8000	/* must be 2**n (0x1000 about 1/2 second) */
+#define CMX_BUFF_HALF	0x4000	/* CMX_BUFF_SIZE / 2 */
+#define CMX_BUFF_MASK	0x7fff	/* CMX_BUFF_SIZE - 1 */
+
+/* how many seconds will we check the lowest delay until the jitter buffer
+   is reduced by that delay */
+#define MAX_SECONDS_JITTER_CHECK 5
+
+extern struct timer_list dsp_spl_tl;
+
+/* the datatype need to match jiffies datatype */
+extern unsigned long dsp_spl_jiffies;
+
+/* the structure of conferences:
+ *
+ * each conference has a unique number, given by user space.
+ * the conferences are linked in a chain.
+ * each conference has members linked in a chain.
+ * each dsplayer points to a member, each member points to a dsplayer.
+ */
+
+/* all members within a conference (this is linked 1:1 with the dsp) */
+struct dsp;
+struct dsp_conf_member {
+	struct list_head	list;
+	struct dsp		*dsp;
+};
+
+/* the list of all conferences */
+struct dsp_conf {
+	struct list_head	list;
+	u32			id;
+	/* all cmx stacks with the same ID are
+	   connected */
+	struct list_head	mlist;
+	int			software; /* conf is processed by software */
+	int			hardware; /* conf is processed by hardware */
+	/* note: if both unset, has only one member */
+};
+
+
+/**************
+ * DTMF stuff *
+ **************/
+
+#define DSP_DTMF_NPOINTS 102
+
+#define ECHOCAN_BUFF_SIZE 0x400 /* must be 2**n */
+#define ECHOCAN_BUFF_MASK 0x3ff /* -1 */
+
+struct dsp_dtmf {
+	int		enable; /* dtmf is enabled */
+	int		treshold; /* above this is dtmf (square of) */
+	int		software; /* dtmf uses software decoding */
+	int		hardware; /* dtmf uses hardware decoding */
+	int		size; /* number of bytes in buffer */
+	signed short	buffer[DSP_DTMF_NPOINTS];
+	/* buffers one full dtmf frame */
+	u8		lastwhat, lastdigit;
+	int		count;
+	u8		digits[16]; /* dtmf result */
+};
+
+
+/******************
+ * pipeline stuff *
+ ******************/
+struct dsp_pipeline {
+	rwlock_t  lock;
+	struct list_head list;
+	int inuse;
+};
+
+/***************
+ * tones stuff *
+ ***************/
+
+struct dsp_tone {
+	int		software; /* tones are generated by software */
+	int		hardware; /* tones are generated by hardware */
+	int		tone;
+	void		*pattern;
+	int		count;
+	int		index;
+	struct timer_list tl;
+};
+
+/***************
+ * echo stuff *
+ ***************/
+
+struct dsp_echo {
+	int		software; /* echo is generated by software */
+	int		hardware; /* echo is generated by hardware */
+};
+
+/*****************
+ * general stuff *
+ *****************/
+
+struct dsp {
+	struct list_head list;
+	struct mISDNchannel	ch;
+	struct mISDNchannel	*up;
+	unsigned char	name[64];
+	int		b_active;
+	struct dsp_echo	echo;
+	int		rx_disabled; /* what the user wants */
+	int		rx_is_off; /* what the card is */
+	int		tx_mix;
+	struct dsp_tone	tone;
+	struct dsp_dtmf	dtmf;
+	int		tx_volume, rx_volume;
+
+	/* queue for sending frames */
+	struct work_struct	workq;
+	struct sk_buff_head	sendq;
+	int		hdlc;	/* if mode is hdlc */
+	int		data_pending;	/* currently an unconfirmed frame */
+
+	/* conference stuff */
+	u32		conf_id;
+	struct dsp_conf	*conf;
+	struct dsp_conf_member
+	*member;
+
+	/* buffer stuff */
+	int		rx_W; /* current write pos for data without timestamp */
+	int		rx_R; /* current read pos for transmit clock */
+	int		rx_init; /* if set, pointers will be adjusted first */
+	int		tx_W; /* current write pos for transmit data */
+	int		tx_R; /* current read pos for transmit clock */
+	int		rx_delay[MAX_SECONDS_JITTER_CHECK];
+	int		tx_delay[MAX_SECONDS_JITTER_CHECK];
+	u8		tx_buff[CMX_BUFF_SIZE];
+	u8		rx_buff[CMX_BUFF_SIZE];
+	int		last_tx; /* if set, we transmitted last poll interval */
+	int		cmx_delay; /* initial delay of buffers,
+				      or 0 for dynamic jitter buffer */
+	int		tx_dejitter; /* if set, dejitter tx buffer */
+	int		tx_data; /* enables tx-data of CMX to upper layer */
+
+	/* hardware stuff */
+	struct dsp_features features;
+	int		features_rx_off; /* set if rx_off is featured */
+	int		features_fill_empty; /* set if fill_empty is featured */
+	int		pcm_slot_rx; /* current PCM slot (or -1) */
+	int		pcm_bank_rx;
+	int		pcm_slot_tx;
+	int		pcm_bank_tx;
+	int		hfc_conf; /* unique id of current conference (or -1) */
+
+	/* encryption stuff */
+	int		bf_enable;
+	u32		bf_p[18];
+	u32		bf_s[1024];
+	int		bf_crypt_pos;
+	u8		bf_data_in[9];
+	u8		bf_crypt_out[9];
+	int		bf_decrypt_in_pos;
+	int		bf_decrypt_out_pos;
+	u8		bf_crypt_inring[16];
+	u8		bf_data_out[9];
+	int		bf_sync;
+
+	struct dsp_pipeline
+	pipeline;
+};
+
+/* functions */
+
+extern void dsp_change_volume(struct sk_buff *skb, int volume);
+
+extern struct list_head dsp_ilist;
+extern struct list_head conf_ilist;
+extern void dsp_cmx_debug(struct dsp *dsp);
+extern void dsp_cmx_hardware(struct dsp_conf *conf, struct dsp *dsp);
+extern int dsp_cmx_conf(struct dsp *dsp, u32 conf_id);
+extern void dsp_cmx_receive(struct dsp *dsp, struct sk_buff *skb);
+extern void dsp_cmx_hdlc(struct dsp *dsp, struct sk_buff *skb);
+extern void dsp_cmx_send(struct timer_list *arg);
+extern void dsp_cmx_transmit(struct dsp *dsp, struct sk_buff *skb);
+extern int dsp_cmx_del_conf_member(struct dsp *dsp);
+extern int dsp_cmx_del_conf(struct dsp_conf *conf);
+
+extern void dsp_dtmf_goertzel_init(struct dsp *dsp);
+extern void dsp_dtmf_hardware(struct dsp *dsp);
+extern u8 *dsp_dtmf_goertzel_decode(struct dsp *dsp, u8 *data, int len,
+				    int fmt);
+
+extern int dsp_tone(struct dsp *dsp, int tone);
+extern void dsp_tone_copy(struct dsp *dsp, u8 *data, int len);
+extern void dsp_tone_timeout(struct timer_list *t);
+
+extern void dsp_bf_encrypt(struct dsp *dsp, u8 *data, int len);
+extern void dsp_bf_decrypt(struct dsp *dsp, u8 *data, int len);
+extern int dsp_bf_init(struct dsp *dsp, const u8 *key, unsigned int keylen);
+extern void dsp_bf_cleanup(struct dsp *dsp);
+
+extern int  dsp_pipeline_module_init(void);
+extern void dsp_pipeline_module_exit(void);
+extern int  dsp_pipeline_init(struct dsp_pipeline *pipeline);
+extern void dsp_pipeline_destroy(struct dsp_pipeline *pipeline);
+extern int  dsp_pipeline_build(struct dsp_pipeline *pipeline, const char *cfg);
+extern void dsp_pipeline_process_tx(struct dsp_pipeline *pipeline, u8 *data,
+				    int len);
+extern void dsp_pipeline_process_rx(struct dsp_pipeline *pipeline, u8 *data,
+				    int len, unsigned int txlen);
diff --git a/drivers/isdn/mISDN/dsp_audio.c b/drivers/isdn/mISDN/dsp_audio.c
new file mode 100644
index 000000000..bbef98e7a
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_audio.c
@@ -0,0 +1,421 @@
+/*
+ * Audio support data for mISDN_dsp.
+ *
+ * Copyright 2002/2003 by Andreas Eversberg (jolly@eversberg.eu)
+ * Rewritten by Peter
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include <linux/export.h>
+#include <linux/bitrev.h>
+#include "core.h"
+#include "dsp.h"
+
+/* ulaw[unsigned char] -> signed 16-bit */
+s32 dsp_audio_ulaw_to_s32[256];
+/* alaw[unsigned char] -> signed 16-bit */
+s32 dsp_audio_alaw_to_s32[256];
+
+s32 *dsp_audio_law_to_s32;
+EXPORT_SYMBOL(dsp_audio_law_to_s32);
+
+/* signed 16-bit -> law */
+u8 dsp_audio_s16_to_law[65536];
+EXPORT_SYMBOL(dsp_audio_s16_to_law);
+
+/* alaw -> ulaw */
+u8 dsp_audio_alaw_to_ulaw[256];
+/* ulaw -> alaw */
+static u8 dsp_audio_ulaw_to_alaw[256];
+u8 dsp_silence;
+
+
+/*****************************************************
+ * generate table for conversion of s16 to alaw/ulaw *
+ *****************************************************/
+
+#define AMI_MASK 0x55
+
+static inline unsigned char linear2alaw(short int linear)
+{
+	int mask;
+	int seg;
+	int pcm_val;
+	static int seg_end[8] = {
+		0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF
+	};
+
+	pcm_val = linear;
+	if (pcm_val >= 0) {
+		/* Sign (7th) bit = 1 */
+		mask = AMI_MASK | 0x80;
+	} else {
+		/* Sign bit = 0 */
+		mask = AMI_MASK;
+		pcm_val = -pcm_val;
+	}
+
+	/* Convert the scaled magnitude to segment number. */
+	for (seg = 0; seg < 8; seg++) {
+		if (pcm_val <= seg_end[seg])
+			break;
+	}
+	/* Combine the sign, segment, and quantization bits. */
+	return  ((seg << 4) |
+		 ((pcm_val >> ((seg)  ?  (seg + 3)  :  4)) & 0x0F)) ^ mask;
+}
+
+
+static inline short int alaw2linear(unsigned char alaw)
+{
+	int i;
+	int seg;
+
+	alaw ^= AMI_MASK;
+	i = ((alaw & 0x0F) << 4) + 8 /* rounding error */;
+	seg = (((int) alaw & 0x70) >> 4);
+	if (seg)
+		i = (i + 0x100) << (seg - 1);
+	return (short int) ((alaw & 0x80)  ?  i  :  -i);
+}
+
+static inline short int ulaw2linear(unsigned char ulaw)
+{
+	short mu, e, f, y;
+	static short etab[] = {0, 132, 396, 924, 1980, 4092, 8316, 16764};
+
+	mu = 255 - ulaw;
+	e = (mu & 0x70) / 16;
+	f = mu & 0x0f;
+	y = f * (1 << (e + 3));
+	y += etab[e];
+	if (mu & 0x80)
+		y = -y;
+	return y;
+}
+
+#define BIAS 0x84   /*!< define the add-in bias for 16 bit samples */
+
+static unsigned char linear2ulaw(short sample)
+{
+	static int exp_lut[256] = {
+		0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
+		4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7};
+	int sign, exponent, mantissa;
+	unsigned char ulawbyte;
+
+	/* Get the sample into sign-magnitude. */
+	sign = (sample >> 8) & 0x80;	  /* set aside the sign */
+	if (sign != 0)
+		sample = -sample;	      /* get magnitude */
+
+	/* Convert from 16 bit linear to ulaw. */
+	sample = sample + BIAS;
+	exponent = exp_lut[(sample >> 7) & 0xFF];
+	mantissa = (sample >> (exponent + 3)) & 0x0F;
+	ulawbyte = ~(sign | (exponent << 4) | mantissa);
+
+	return ulawbyte;
+}
+
+void dsp_audio_generate_law_tables(void)
+{
+	int i;
+	for (i = 0; i < 256; i++)
+		dsp_audio_alaw_to_s32[i] = alaw2linear(bitrev8((u8)i));
+
+	for (i = 0; i < 256; i++)
+		dsp_audio_ulaw_to_s32[i] = ulaw2linear(bitrev8((u8)i));
+
+	for (i = 0; i < 256; i++) {
+		dsp_audio_alaw_to_ulaw[i] =
+			linear2ulaw(dsp_audio_alaw_to_s32[i]);
+		dsp_audio_ulaw_to_alaw[i] =
+			linear2alaw(dsp_audio_ulaw_to_s32[i]);
+	}
+}
+
+void
+dsp_audio_generate_s2law_table(void)
+{
+	int i;
+
+	if (dsp_options & DSP_OPT_ULAW) {
+		/* generating ulaw-table */
+		for (i = -32768; i < 32768; i++) {
+			dsp_audio_s16_to_law[i & 0xffff] =
+				bitrev8(linear2ulaw(i));
+		}
+	} else {
+		/* generating alaw-table */
+		for (i = -32768; i < 32768; i++) {
+			dsp_audio_s16_to_law[i & 0xffff] =
+				bitrev8(linear2alaw(i));
+		}
+	}
+}
+
+
+/*
+ * the seven bit sample is the number of every second alaw-sample ordered by
+ * aplitude. 0x00 is negative, 0x7f is positive amplitude.
+ */
+u8 dsp_audio_seven2law[128];
+u8 dsp_audio_law2seven[256];
+
+/********************************************************************
+ * generate table for conversion law from/to 7-bit alaw-like sample *
+ ********************************************************************/
+
+void
+dsp_audio_generate_seven(void)
+{
+	int i, j, k;
+	u8 spl;
+	u8 sorted_alaw[256];
+
+	/* generate alaw table, sorted by the linear value */
+	for (i = 0; i < 256; i++) {
+		j = 0;
+		for (k = 0; k < 256; k++) {
+			if (dsp_audio_alaw_to_s32[k]
+			    < dsp_audio_alaw_to_s32[i])
+				j++;
+		}
+		sorted_alaw[j] = i;
+	}
+
+	/* generate tabels */
+	for (i = 0; i < 256; i++) {
+		/* spl is the source: the law-sample (converted to alaw) */
+		spl = i;
+		if (dsp_options & DSP_OPT_ULAW)
+			spl = dsp_audio_ulaw_to_alaw[i];
+		/* find the 7-bit-sample */
+		for (j = 0; j < 256; j++) {
+			if (sorted_alaw[j] == spl)
+				break;
+		}
+		/* write 7-bit audio value */
+		dsp_audio_law2seven[i] = j >> 1;
+	}
+	for (i = 0; i < 128; i++) {
+		spl = sorted_alaw[i << 1];
+		if (dsp_options & DSP_OPT_ULAW)
+			spl = dsp_audio_alaw_to_ulaw[spl];
+		dsp_audio_seven2law[i] = spl;
+	}
+}
+
+
+/* mix 2*law -> law */
+u8 dsp_audio_mix_law[65536];
+
+/******************************************************
+ * generate mix table to mix two law samples into one *
+ ******************************************************/
+
+void
+dsp_audio_generate_mix_table(void)
+{
+	int i, j;
+	s32 sample;
+
+	i = 0;
+	while (i < 256) {
+		j = 0;
+		while (j < 256) {
+			sample = dsp_audio_law_to_s32[i];
+			sample += dsp_audio_law_to_s32[j];
+			if (sample > 32767)
+				sample = 32767;
+			if (sample < -32768)
+				sample = -32768;
+			dsp_audio_mix_law[(i << 8) | j] =
+				dsp_audio_s16_to_law[sample & 0xffff];
+			j++;
+		}
+		i++;
+	}
+}
+
+
+/*************************************
+ * generate different volume changes *
+ *************************************/
+
+static u8 dsp_audio_reduce8[256];
+static u8 dsp_audio_reduce7[256];
+static u8 dsp_audio_reduce6[256];
+static u8 dsp_audio_reduce5[256];
+static u8 dsp_audio_reduce4[256];
+static u8 dsp_audio_reduce3[256];
+static u8 dsp_audio_reduce2[256];
+static u8 dsp_audio_reduce1[256];
+static u8 dsp_audio_increase1[256];
+static u8 dsp_audio_increase2[256];
+static u8 dsp_audio_increase3[256];
+static u8 dsp_audio_increase4[256];
+static u8 dsp_audio_increase5[256];
+static u8 dsp_audio_increase6[256];
+static u8 dsp_audio_increase7[256];
+static u8 dsp_audio_increase8[256];
+
+static u8 *dsp_audio_volume_change[16] = {
+	dsp_audio_reduce8,
+	dsp_audio_reduce7,
+	dsp_audio_reduce6,
+	dsp_audio_reduce5,
+	dsp_audio_reduce4,
+	dsp_audio_reduce3,
+	dsp_audio_reduce2,
+	dsp_audio_reduce1,
+	dsp_audio_increase1,
+	dsp_audio_increase2,
+	dsp_audio_increase3,
+	dsp_audio_increase4,
+	dsp_audio_increase5,
+	dsp_audio_increase6,
+	dsp_audio_increase7,
+	dsp_audio_increase8,
+};
+
+void
+dsp_audio_generate_volume_changes(void)
+{
+	register s32 sample;
+	int i;
+	int num[]   = { 110, 125, 150, 175, 200, 300, 400, 500 };
+	int denum[] = { 100, 100, 100, 100, 100, 100, 100, 100 };
+
+	i = 0;
+	while (i < 256) {
+		dsp_audio_reduce8[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[7] / num[7]) & 0xffff];
+		dsp_audio_reduce7[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[6] / num[6]) & 0xffff];
+		dsp_audio_reduce6[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[5] / num[5]) & 0xffff];
+		dsp_audio_reduce5[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[4] / num[4]) & 0xffff];
+		dsp_audio_reduce4[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[3] / num[3]) & 0xffff];
+		dsp_audio_reduce3[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[2] / num[2]) & 0xffff];
+		dsp_audio_reduce2[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[1] / num[1]) & 0xffff];
+		dsp_audio_reduce1[i] = dsp_audio_s16_to_law[
+			(dsp_audio_law_to_s32[i] * denum[0] / num[0]) & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[0] / denum[0];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase1[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[1] / denum[1];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase2[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[2] / denum[2];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase3[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[3] / denum[3];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase4[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[4] / denum[4];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase5[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[5] / denum[5];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase6[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[6] / denum[6];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase7[i] = dsp_audio_s16_to_law[sample & 0xffff];
+		sample = dsp_audio_law_to_s32[i] * num[7] / denum[7];
+		if (sample < -32768)
+			sample = -32768;
+		else if (sample > 32767)
+			sample = 32767;
+		dsp_audio_increase8[i] = dsp_audio_s16_to_law[sample & 0xffff];
+
+		i++;
+	}
+}
+
+
+/**************************************
+ * change the volume of the given skb *
+ **************************************/
+
+/* this is a helper function for changing volume of skb. the range may be
+ * -8 to 8, which is a shift to the power of 2. 0 == no volume, 3 == volume*8
+ */
+void
+dsp_change_volume(struct sk_buff *skb, int volume)
+{
+	u8 *volume_change;
+	int i, ii;
+	u8 *p;
+	int shift;
+
+	if (volume == 0)
+		return;
+
+	/* get correct conversion table */
+	if (volume < 0) {
+		shift = volume + 8;
+		if (shift < 0)
+			shift = 0;
+	} else {
+		shift = volume + 7;
+		if (shift > 15)
+			shift = 15;
+	}
+	volume_change = dsp_audio_volume_change[shift];
+	i = 0;
+	ii = skb->len;
+	p = skb->data;
+	/* change volume */
+	while (i < ii) {
+		*p = volume_change[*p];
+		p++;
+		i++;
+	}
+}
diff --git a/drivers/isdn/mISDN/dsp_biquad.h b/drivers/isdn/mISDN/dsp_biquad.h
new file mode 100644
index 000000000..f40d52a4c
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_biquad.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * biquad.h - General telephony bi-quad section routines (currently this just
+ *            handles canonic/type 2 form)
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2001 Steve Underwood
+ *
+ * All rights reserved.
+ */
+
+struct biquad2_state {
+	int32_t gain;
+	int32_t a1;
+	int32_t a2;
+	int32_t b1;
+	int32_t b2;
+
+	int32_t z1;
+	int32_t z2;
+};
+
+static inline void biquad2_init(struct biquad2_state *bq,
+				int32_t gain, int32_t a1, int32_t a2, int32_t b1, int32_t b2)
+{
+	bq->gain = gain;
+	bq->a1 = a1;
+	bq->a2 = a2;
+	bq->b1 = b1;
+	bq->b2 = b2;
+
+	bq->z1 = 0;
+	bq->z2 = 0;
+}
+
+static inline int16_t biquad2(struct biquad2_state *bq, int16_t sample)
+{
+	int32_t y;
+	int32_t z0;
+
+	z0 = sample * bq->gain + bq->z1 * bq->a1 + bq->z2 * bq->a2;
+	y = z0 + bq->z1 * bq->b1 + bq->z2 * bq->b2;
+
+	bq->z2 = bq->z1;
+	bq->z1 = z0 >> 15;
+	y >>= 15;
+	return  y;
+}
diff --git a/drivers/isdn/mISDN/dsp_blowfish.c b/drivers/isdn/mISDN/dsp_blowfish.c
new file mode 100644
index 000000000..0aa572f38
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_blowfish.c
@@ -0,0 +1,672 @@
+/*
+ * Blowfish encryption/decryption for mISDN_dsp.
+ *
+ * Copyright Andreas Eversberg (jolly@eversberg.eu)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include "core.h"
+#include "dsp.h"
+
+/*
+ * how to encode a sample stream to 64-bit blocks that will be encryped
+ *
+ * first of all, data is collected until a block of 9 samples are received.
+ * of course, a packet may have much more than 9 sample, but is may have
+ * not excacly the multiple of 9 samples. if there is a rest, the next
+ * received data will complete the block.
+ *
+ * the block is then converted to 9 uLAW samples without the least sigificant
+ * bit. the result is a 7-bit encoded sample.
+ *
+ * the samples will be reoganised to form 8 bytes of data:
+ * (5(6) means: encoded sample no. 5, bit 6)
+ *
+ * 0(6) 0(5) 0(4) 0(3) 0(2) 0(1) 0(0) 1(6)
+ * 1(5) 1(4) 1(3) 1(2) 1(1) 1(0) 2(6) 2(5)
+ * 2(4) 2(3) 2(2) 2(1) 2(0) 3(6) 3(5) 3(4)
+ * 3(3) 3(2) 3(1) 3(0) 4(6) 4(5) 4(4) 4(3)
+ * 4(2) 4(1) 4(0) 5(6) 5(5) 5(4) 5(3) 5(2)
+ * 5(1) 5(0) 6(6) 6(5) 6(4) 6(3) 6(2) 6(1)
+ * 6(0) 7(6) 7(5) 7(4) 7(3) 7(2) 7(1) 7(0)
+ * 8(6) 8(5) 8(4) 8(3) 8(2) 8(1) 8(0)
+ *
+ * the missing bit 0 of the last byte is filled with some
+ * random noise, to fill all 8 bytes.
+ *
+ * the 8 bytes will be encrypted using blowfish.
+ *
+ * the result will be converted into 9 bytes. the bit 7 is used for
+ * checksumme (CS) for sync (0, 1) and for the last bit:
+ * (5(6) means: crypted byte 5, bit 6)
+ *
+ * 1    0(7) 0(6) 0(5) 0(4) 0(3) 0(2) 0(1)
+ * 0    0(0) 1(7) 1(6) 1(5) 1(4) 1(3) 1(2)
+ * 0    1(1) 1(0) 2(7) 2(6) 2(5) 2(4) 2(3)
+ * 0    2(2) 2(1) 2(0) 3(7) 3(6) 3(5) 3(4)
+ * 0    3(3) 3(2) 3(1) 3(0) 4(7) 4(6) 4(5)
+ * CS   4(4) 4(3) 4(2) 4(1) 4(0) 5(7) 5(6)
+ * CS   5(5) 5(4) 5(3) 5(2) 5(1) 5(0) 6(7)
+ * CS   6(6) 6(5) 6(4) 6(3) 6(2) 6(1) 6(0)
+ * 7(0) 7(6) 7(5) 7(4) 7(3) 7(2) 7(1) 7(0)
+ *
+ * the checksum is used to detect transmission errors and frame drops.
+ *
+ * synchronisation of received block is done by shifting the upper bit of each
+ * byte (bit 7) to a shift register. if the rigister has the first five bits
+ * (10000), this is used to find the sync. only if sync has been found, the
+ * current block of 9 received bytes are decrypted. before that the check
+ * sum is calculated. if it is incorrect the block is dropped.
+ * this will avoid loud noise due to corrupt encrypted data.
+ *
+ * if the last block is corrupt, the current decoded block is repeated
+ * until a valid block has been received.
+ */
+
+/*
+ *  some blowfish parts are taken from the
+ * crypto-api for faster implementation
+ */
+
+struct bf_ctx {
+	u32 p[18];
+	u32 s[1024];
+};
+
+static const u32 bf_pbox[16 + 2] = {
+	0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344,
+	0xa4093822, 0x299f31d0, 0x082efa98, 0xec4e6c89,
+	0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c,
+	0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917,
+	0x9216d5d9, 0x8979fb1b,
+};
+
+static const u32 bf_sbox[256 * 4] = {
+	0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7,
+	0xb8e1afed, 0x6a267e96, 0xba7c9045, 0xf12c7f99,
+	0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16,
+	0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e,
+	0x0d95748f, 0x728eb658, 0x718bcd58, 0x82154aee,
+	0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013,
+	0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef,
+	0x8e79dcb0, 0x603a180e, 0x6c9e0e8b, 0xb01e8a3e,
+	0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60,
+	0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440,
+	0x55ca396a, 0x2aab10b6, 0xb4cc5c34, 0x1141e8ce,
+	0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a,
+	0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e,
+	0xafd6ba33, 0x6c24cf5c, 0x7a325381, 0x28958677,
+	0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193,
+	0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032,
+	0xef845d5d, 0xe98575b1, 0xdc262302, 0xeb651b88,
+	0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239,
+	0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e,
+	0x21c66842, 0xf6e96c9a, 0x670c9c61, 0xabd388f0,
+	0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3,
+	0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98,
+	0xa1f1651d, 0x39af0176, 0x66ca593e, 0x82430e88,
+	0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe,
+	0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6,
+	0x4ed3aa62, 0x363f7706, 0x1bfedf72, 0x429b023d,
+	0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b,
+	0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7,
+	0xe3fe501a, 0xb6794c3b, 0x976ce0bd, 0x04c006ba,
+	0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463,
+	0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f,
+	0x6dfc511f, 0x9b30952c, 0xcc814544, 0xaf5ebd09,
+	0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3,
+	0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb,
+	0x5579c0bd, 0x1a60320a, 0xd6a100c6, 0x402c7279,
+	0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8,
+	0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab,
+	0x323db5fa, 0xfd238760, 0x53317b48, 0x3e00df82,
+	0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db,
+	0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573,
+	0x695b27b0, 0xbbca58c8, 0xe1ffa35d, 0xb8f011a0,
+	0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b,
+	0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790,
+	0xe1ddf2da, 0xa4cb7e33, 0x62fb1341, 0xcee4c6e8,
+	0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4,
+	0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0,
+	0xd08ed1d0, 0xafc725e0, 0x8e3c5b2f, 0x8e7594b7,
+	0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c,
+	0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad,
+	0x2f2f2218, 0xbe0e1777, 0xea752dfe, 0x8b021fa1,
+	0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299,
+	0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9,
+	0x165fa266, 0x80957705, 0x93cc7314, 0x211a1477,
+	0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf,
+	0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49,
+	0x00250e2d, 0x2071b35e, 0x226800bb, 0x57b8e0af,
+	0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa,
+	0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5,
+	0x83260376, 0x6295cfa9, 0x11c81968, 0x4e734a41,
+	0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915,
+	0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400,
+	0x08ba6fb5, 0x571be91f, 0xf296ec6b, 0x2a0dd915,
+	0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664,
+	0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a,
+	0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623,
+	0xad6ea6b0, 0x49a7df7d, 0x9cee60b8, 0x8fedb266,
+	0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1,
+	0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e,
+	0x3f54989a, 0x5b429d65, 0x6b8fe4d6, 0x99f73fd6,
+	0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1,
+	0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e,
+	0x09686b3f, 0x3ebaefc9, 0x3c971814, 0x6b6a70a1,
+	0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737,
+	0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8,
+	0xb03ada37, 0xf0500c0d, 0xf01c1f04, 0x0200b3ff,
+	0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd,
+	0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701,
+	0x3ae5e581, 0x37c2dadc, 0xc8b57634, 0x9af3dda7,
+	0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41,
+	0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331,
+	0x4e548b38, 0x4f6db908, 0x6f420d03, 0xf60a04bf,
+	0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af,
+	0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e,
+	0x5512721f, 0x2e6b7124, 0x501adde6, 0x9f84cd87,
+	0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c,
+	0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2,
+	0xef1c1847, 0x3215d908, 0xdd433b37, 0x24c2ba16,
+	0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd,
+	0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b,
+	0x043556f1, 0xd7a3c76b, 0x3c11183b, 0x5924a509,
+	0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e,
+	0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3,
+	0x771fe71c, 0x4e3d06fa, 0x2965dcb9, 0x99e71d0f,
+	0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a,
+	0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4,
+	0xf2f74ea7, 0x361d2b3d, 0x1939260f, 0x19c27960,
+	0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66,
+	0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28,
+	0xc332ddef, 0xbe6c5aa5, 0x65582185, 0x68ab9802,
+	0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84,
+	0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510,
+	0x13cca830, 0xeb61bd96, 0x0334fe1e, 0xaa0363cf,
+	0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14,
+	0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e,
+	0x648b1eaf, 0x19bdf0ca, 0xa02369b9, 0x655abb50,
+	0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7,
+	0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8,
+	0xf837889a, 0x97e32d77, 0x11ed935f, 0x16681281,
+	0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99,
+	0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696,
+	0xcdb30aeb, 0x532e3054, 0x8fd948e4, 0x6dbc3128,
+	0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73,
+	0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0,
+	0x45eee2b6, 0xa3aaabea, 0xdb6c4f15, 0xfacb4fd0,
+	0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105,
+	0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250,
+	0xcf62a1f2, 0x5b8d2646, 0xfc8883a0, 0xc1c7b6a3,
+	0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285,
+	0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00,
+	0x58428d2a, 0x0c55f5ea, 0x1dadf43e, 0x233f7061,
+	0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb,
+	0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e,
+	0xa6078084, 0x19f8509e, 0xe8efd855, 0x61d99735,
+	0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc,
+	0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9,
+	0xdb73dbd3, 0x105588cd, 0x675fda79, 0xe3674340,
+	0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20,
+	0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7,
+	0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934,
+	0x411520f7, 0x7602d4f7, 0xbcf46b2e, 0xd4a20068,
+	0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af,
+	0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840,
+	0x4d95fc1d, 0x96b591af, 0x70f4ddd3, 0x66a02f45,
+	0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504,
+	0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a,
+	0x28507825, 0x530429f4, 0x0a2c86da, 0xe9b66dfb,
+	0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee,
+	0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6,
+	0xaace1e7c, 0xd3375fec, 0xce78a399, 0x406b2a42,
+	0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b,
+	0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2,
+	0x3a6efa74, 0xdd5b4332, 0x6841e7f7, 0xca7820fb,
+	0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527,
+	0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b,
+	0x55a867bc, 0xa1159a58, 0xcca92963, 0x99e1db33,
+	0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c,
+	0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3,
+	0x95c11548, 0xe4c66d22, 0x48c1133f, 0xc70f86dc,
+	0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17,
+	0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564,
+	0x257b7834, 0x602a9c60, 0xdff8e8a3, 0x1f636c1b,
+	0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115,
+	0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922,
+	0x85b2a20e, 0xe6ba0d99, 0xde720c8c, 0x2da2f728,
+	0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0,
+	0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e,
+	0x0a476341, 0x992eff74, 0x3a6f6eab, 0xf4f8fd37,
+	0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d,
+	0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804,
+	0xf1290dc7, 0xcc00ffa3, 0xb5390f92, 0x690fed0b,
+	0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3,
+	0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb,
+	0x37392eb3, 0xcc115979, 0x8026e297, 0xf42e312d,
+	0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c,
+	0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350,
+	0x1a6b1018, 0x11caedfa, 0x3d25bdd8, 0xe2e1c3c9,
+	0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a,
+	0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe,
+	0x9dbc8057, 0xf0f7c086, 0x60787bf8, 0x6003604d,
+	0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc,
+	0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f,
+	0x77a057be, 0xbde8ae24, 0x55464299, 0xbf582e61,
+	0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2,
+	0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9,
+	0x7aeb2661, 0x8b1ddf84, 0x846a0e79, 0x915f95e2,
+	0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c,
+	0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e,
+	0xb77f19b6, 0xe0a9dc09, 0x662d09a1, 0xc4324633,
+	0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10,
+	0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169,
+	0xdcb7da83, 0x573906fe, 0xa1e2ce9b, 0x4fcd7f52,
+	0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027,
+	0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5,
+	0xf0177a28, 0xc0f586e0, 0x006058aa, 0x30dc7d62,
+	0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634,
+	0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76,
+	0x6f05e409, 0x4b7c0188, 0x39720a3d, 0x7c927c24,
+	0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc,
+	0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4,
+	0x1e50ef5e, 0xb161e6f8, 0xa28514d9, 0x6c51133c,
+	0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837,
+	0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0,
+	0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b,
+	0x5cb0679e, 0x4fa33742, 0xd3822740, 0x99bc9bbe,
+	0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b,
+	0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4,
+	0x5748ab2f, 0xbc946e79, 0xc6a376d2, 0x6549c2c8,
+	0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6,
+	0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304,
+	0xa1fad5f0, 0x6a2d519a, 0x63ef8ce2, 0x9a86ee22,
+	0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4,
+	0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6,
+	0x2826a2f9, 0xa73a3ae1, 0x4ba99586, 0xef5562e9,
+	0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59,
+	0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593,
+	0xe990fd5a, 0x9e34d797, 0x2cf0b7d9, 0x022b8b51,
+	0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28,
+	0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c,
+	0xe029ac71, 0xe019a5e6, 0x47b0acfd, 0xed93fa9b,
+	0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28,
+	0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c,
+	0x15056dd4, 0x88f46dba, 0x03a16125, 0x0564f0bd,
+	0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a,
+	0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319,
+	0x7533d928, 0xb155fdf5, 0x03563482, 0x8aba3cbb,
+	0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f,
+	0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991,
+	0xea7a90c2, 0xfb3e7bce, 0x5121ce64, 0x774fbe32,
+	0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680,
+	0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166,
+	0xb39a460a, 0x6445c0dd, 0x586cdecf, 0x1c20c8ae,
+	0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb,
+	0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5,
+	0x72eacea8, 0xfa6484bb, 0x8d6612ae, 0xbf3c6f47,
+	0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370,
+	0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d,
+	0x4040cb08, 0x4eb4e2cc, 0x34d2466a, 0x0115af84,
+	0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048,
+	0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8,
+	0x611560b1, 0xe7933fdc, 0xbb3a792b, 0x344525bd,
+	0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9,
+	0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7,
+	0x1a908749, 0xd44fbd9a, 0xd0dadecb, 0xd50ada38,
+	0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f,
+	0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c,
+	0xbf97222c, 0x15e6fc2a, 0x0f91fc71, 0x9b941525,
+	0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1,
+	0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442,
+	0xe0ec6e0e, 0x1698db3b, 0x4c98a0be, 0x3278e964,
+	0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e,
+	0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8,
+	0xdf359f8d, 0x9b992f2e, 0xe60b6f47, 0x0fe3f11d,
+	0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f,
+	0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299,
+	0xf523f357, 0xa6327623, 0x93a83531, 0x56cccd02,
+	0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc,
+	0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614,
+	0xe6c6c7bd, 0x327a140a, 0x45e1d006, 0xc3f27b9a,
+	0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6,
+	0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b,
+	0x53113ec0, 0x1640e3d3, 0x38abbd60, 0x2547adf0,
+	0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060,
+	0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e,
+	0x1948c25c, 0x02fb8a8c, 0x01c36ae4, 0xd6ebe1f9,
+	0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f,
+	0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6,
+};
+
+/*
+ * Round loop unrolling macros, S is a pointer to a S-Box array
+ * organized in 4 unsigned longs at a row.
+ */
+#define GET32_3(x) (((x) & 0xff))
+#define GET32_2(x) (((x) >> (8)) & (0xff))
+#define GET32_1(x) (((x) >> (16)) & (0xff))
+#define GET32_0(x) (((x) >> (24)) & (0xff))
+
+#define bf_F(x) (((S[GET32_0(x)] + S[256 + GET32_1(x)]) ^	\
+		  S[512 + GET32_2(x)]) + S[768 + GET32_3(x)])
+
+#define EROUND(a, b, n)  do { b ^= P[n]; a ^= bf_F(b); } while (0)
+#define DROUND(a, b, n)  do { a ^= bf_F(b); b ^= P[n]; } while (0)
+
+
+/*
+ * encrypt isdn data frame
+ * every block with 9 samples is encrypted
+ */
+void
+dsp_bf_encrypt(struct dsp *dsp, u8 *data, int len)
+{
+	int i = 0, j = dsp->bf_crypt_pos;
+	u8 *bf_data_in = dsp->bf_data_in;
+	u8 *bf_crypt_out = dsp->bf_crypt_out;
+	u32 *P = dsp->bf_p;
+	u32 *S = dsp->bf_s;
+	u32 yl, yr;
+	u32 cs;
+	u8 nibble;
+
+	while (i < len) {
+		/* collect a block of 9 samples */
+		if (j < 9) {
+			bf_data_in[j] = *data;
+			*data++ = bf_crypt_out[j++];
+			i++;
+			continue;
+		}
+		j = 0;
+		/* transcode 9 samples xlaw to 8 bytes */
+		yl = dsp_audio_law2seven[bf_data_in[0]];
+		yl = (yl << 7) | dsp_audio_law2seven[bf_data_in[1]];
+		yl = (yl << 7) | dsp_audio_law2seven[bf_data_in[2]];
+		yl = (yl << 7) | dsp_audio_law2seven[bf_data_in[3]];
+		nibble = dsp_audio_law2seven[bf_data_in[4]];
+		yr = nibble;
+		yl = (yl << 4) | (nibble >> 3);
+		yr = (yr << 7) | dsp_audio_law2seven[bf_data_in[5]];
+		yr = (yr << 7) | dsp_audio_law2seven[bf_data_in[6]];
+		yr = (yr << 7) | dsp_audio_law2seven[bf_data_in[7]];
+		yr = (yr << 7) | dsp_audio_law2seven[bf_data_in[8]];
+		yr = (yr << 1) | (bf_data_in[0] & 1);
+
+		/* fill unused bit with random noise of audio input */
+		/* encrypt */
+
+		EROUND(yr, yl, 0);
+		EROUND(yl, yr, 1);
+		EROUND(yr, yl, 2);
+		EROUND(yl, yr, 3);
+		EROUND(yr, yl, 4);
+		EROUND(yl, yr, 5);
+		EROUND(yr, yl, 6);
+		EROUND(yl, yr, 7);
+		EROUND(yr, yl, 8);
+		EROUND(yl, yr, 9);
+		EROUND(yr, yl, 10);
+		EROUND(yl, yr, 11);
+		EROUND(yr, yl, 12);
+		EROUND(yl, yr, 13);
+		EROUND(yr, yl, 14);
+		EROUND(yl, yr, 15);
+		yl ^= P[16];
+		yr ^= P[17];
+
+		/* calculate 3-bit checksumme */
+		cs = yl ^ (yl >> 3) ^ (yl >> 6) ^ (yl >> 9) ^ (yl >> 12) ^ (yl >> 15)
+			^ (yl >> 18) ^ (yl >> 21) ^ (yl >> 24) ^ (yl >> 27) ^ (yl >> 30)
+			^ (yr << 2) ^ (yr >> 1) ^ (yr >> 4) ^ (yr >> 7) ^ (yr >> 10)
+			^ (yr >> 13) ^ (yr >> 16) ^ (yr >> 19) ^ (yr >> 22) ^ (yr >> 25)
+			^ (yr >> 28) ^ (yr >> 31);
+
+		/*
+		 * transcode 8 crypted bytes to 9 data bytes with sync
+		 * and checksum information
+		 */
+		bf_crypt_out[0] = (yl >> 25) | 0x80;
+		bf_crypt_out[1] = (yl >> 18) & 0x7f;
+		bf_crypt_out[2] = (yl >> 11) & 0x7f;
+		bf_crypt_out[3] = (yl >> 4) & 0x7f;
+		bf_crypt_out[4] = ((yl << 3) & 0x78) | ((yr >> 29) & 0x07);
+		bf_crypt_out[5] = ((yr >> 22) & 0x7f) | ((cs << 5) & 0x80);
+		bf_crypt_out[6] = ((yr >> 15) & 0x7f) | ((cs << 6) & 0x80);
+		bf_crypt_out[7] = ((yr >> 8) & 0x7f) | (cs << 7);
+		bf_crypt_out[8] = yr;
+	}
+
+	/* write current count */
+	dsp->bf_crypt_pos = j;
+
+}
+
+
+/*
+ * decrypt isdn data frame
+ * every block with 9 bytes is decrypted
+ */
+void
+dsp_bf_decrypt(struct dsp *dsp, u8 *data, int len)
+{
+	int i = 0;
+	u8 j = dsp->bf_decrypt_in_pos;
+	u8 k = dsp->bf_decrypt_out_pos;
+	u8 *bf_crypt_inring = dsp->bf_crypt_inring;
+	u8 *bf_data_out = dsp->bf_data_out;
+	u16 sync = dsp->bf_sync;
+	u32 *P = dsp->bf_p;
+	u32 *S = dsp->bf_s;
+	u32 yl, yr;
+	u8 nibble;
+	u8 cs, cs0, cs1, cs2;
+
+	while (i < len) {
+		/*
+		 * shift upper bit and rotate data to buffer ring
+		 * send current decrypted data
+		 */
+		sync = (sync << 1) | ((*data) >> 7);
+		bf_crypt_inring[j++ & 15] = *data;
+		*data++ = bf_data_out[k++];
+		i++;
+		if (k == 9)
+			k = 0; /* repeat if no sync has been found */
+		/* check if not in sync */
+		if ((sync & 0x1f0) != 0x100)
+			continue;
+		j -= 9;
+		/* transcode receive data to 64 bit block of encrypted data */
+		yl = bf_crypt_inring[j++ & 15];
+		yl = (yl << 7) | bf_crypt_inring[j++ & 15]; /* bit7 = 0 */
+		yl = (yl << 7) | bf_crypt_inring[j++ & 15]; /* bit7 = 0 */
+		yl = (yl << 7) | bf_crypt_inring[j++ & 15]; /* bit7 = 0 */
+		nibble = bf_crypt_inring[j++ & 15]; /* bit7 = 0 */
+		yr = nibble;
+		yl = (yl << 4) | (nibble >> 3);
+		cs2 = bf_crypt_inring[j++ & 15];
+		yr = (yr << 7) | (cs2 & 0x7f);
+		cs1 = bf_crypt_inring[j++ & 15];
+		yr = (yr << 7) | (cs1 & 0x7f);
+		cs0 = bf_crypt_inring[j++ & 15];
+		yr = (yr << 7) | (cs0 & 0x7f);
+		yr = (yr << 8) | bf_crypt_inring[j++ & 15];
+
+		/* calculate 3-bit checksumme */
+		cs = yl ^ (yl >> 3) ^ (yl >> 6) ^ (yl >> 9) ^ (yl >> 12) ^ (yl >> 15)
+			^ (yl >> 18) ^ (yl >> 21) ^ (yl >> 24) ^ (yl >> 27) ^ (yl >> 30)
+			^ (yr << 2) ^ (yr >> 1) ^ (yr >> 4) ^ (yr >> 7) ^ (yr >> 10)
+			^ (yr >> 13) ^ (yr >> 16) ^ (yr >> 19) ^ (yr >> 22) ^ (yr >> 25)
+			^ (yr >> 28) ^ (yr >> 31);
+
+		/* check if frame is valid */
+		if ((cs & 0x7) != (((cs2 >> 5) & 4) | ((cs1 >> 6) & 2) | (cs0 >> 7))) {
+			if (dsp_debug & DEBUG_DSP_BLOWFISH)
+				printk(KERN_DEBUG
+				       "DSP BLOWFISH: received corrupt frame, "
+				       "checksumme is not correct\n");
+			continue;
+		}
+
+		/* decrypt */
+		yr ^= P[17];
+		yl ^= P[16];
+		DROUND(yl, yr, 15);
+		DROUND(yr, yl, 14);
+		DROUND(yl, yr, 13);
+		DROUND(yr, yl, 12);
+		DROUND(yl, yr, 11);
+		DROUND(yr, yl, 10);
+		DROUND(yl, yr, 9);
+		DROUND(yr, yl, 8);
+		DROUND(yl, yr, 7);
+		DROUND(yr, yl, 6);
+		DROUND(yl, yr, 5);
+		DROUND(yr, yl, 4);
+		DROUND(yl, yr, 3);
+		DROUND(yr, yl, 2);
+		DROUND(yl, yr, 1);
+		DROUND(yr, yl, 0);
+
+		/* transcode 8 crypted bytes to 9 sample bytes */
+		bf_data_out[0] = dsp_audio_seven2law[(yl >> 25) & 0x7f];
+		bf_data_out[1] = dsp_audio_seven2law[(yl >> 18) & 0x7f];
+		bf_data_out[2] = dsp_audio_seven2law[(yl >> 11) & 0x7f];
+		bf_data_out[3] = dsp_audio_seven2law[(yl >> 4) & 0x7f];
+		bf_data_out[4] = dsp_audio_seven2law[((yl << 3) & 0x78) |
+						     ((yr >> 29) & 0x07)];
+
+		bf_data_out[5] = dsp_audio_seven2law[(yr >> 22) & 0x7f];
+		bf_data_out[6] = dsp_audio_seven2law[(yr >> 15) & 0x7f];
+		bf_data_out[7] = dsp_audio_seven2law[(yr >> 8) & 0x7f];
+		bf_data_out[8] = dsp_audio_seven2law[(yr >> 1) & 0x7f];
+		k = 0; /* start with new decoded frame */
+	}
+
+	/* write current count and sync */
+	dsp->bf_decrypt_in_pos = j;
+	dsp->bf_decrypt_out_pos = k;
+	dsp->bf_sync = sync;
+}
+
+
+/* used to encrypt S and P boxes */
+static inline void
+encrypt_block(const u32 *P, const u32 *S, u32 *dst, u32 *src)
+{
+	u32 yl = src[0];
+	u32 yr = src[1];
+
+	EROUND(yr, yl, 0);
+	EROUND(yl, yr, 1);
+	EROUND(yr, yl, 2);
+	EROUND(yl, yr, 3);
+	EROUND(yr, yl, 4);
+	EROUND(yl, yr, 5);
+	EROUND(yr, yl, 6);
+	EROUND(yl, yr, 7);
+	EROUND(yr, yl, 8);
+	EROUND(yl, yr, 9);
+	EROUND(yr, yl, 10);
+	EROUND(yl, yr, 11);
+	EROUND(yr, yl, 12);
+	EROUND(yl, yr, 13);
+	EROUND(yr, yl, 14);
+	EROUND(yl, yr, 15);
+
+	yl ^= P[16];
+	yr ^= P[17];
+
+	dst[0] = yr;
+	dst[1] = yl;
+}
+
+/*
+ * initialize the dsp for encryption and decryption using the same key
+ * Calculates the blowfish S and P boxes for encryption and decryption.
+ * The margin of keylen must be 4-56 bytes.
+ * returns 0 if ok.
+ */
+int
+dsp_bf_init(struct dsp *dsp, const u8 *key, uint keylen)
+{
+	short i, j, count;
+	u32 data[2], temp;
+	u32 *P = (u32 *)dsp->bf_p;
+	u32 *S = (u32 *)dsp->bf_s;
+
+	if (keylen < 4 || keylen > 56)
+		return 1;
+
+	/* Set dsp states */
+	i = 0;
+	while (i < 9) {
+		dsp->bf_crypt_out[i] = 0xff;
+		dsp->bf_data_out[i] = dsp_silence;
+		i++;
+	}
+	dsp->bf_crypt_pos = 0;
+	dsp->bf_decrypt_in_pos = 0;
+	dsp->bf_decrypt_out_pos = 0;
+	dsp->bf_sync = 0x1ff;
+	dsp->bf_enable = 1;
+
+	/* Copy the initialization s-boxes */
+	for (i = 0, count = 0; i < 256; i++)
+		for (j = 0; j < 4; j++, count++)
+			S[count] = bf_sbox[count];
+
+	/* Set the p-boxes */
+	for (i = 0; i < 16 + 2; i++)
+		P[i] = bf_pbox[i];
+
+	/* Actual subkey generation */
+	for (j = 0, i = 0; i < 16 + 2; i++) {
+		temp = (((u32)key[j] << 24) |
+			((u32)key[(j + 1) % keylen] << 16) |
+			((u32)key[(j + 2) % keylen] << 8) |
+			((u32)key[(j + 3) % keylen]));
+
+		P[i] = P[i] ^ temp;
+		j = (j + 4) % keylen;
+	}
+
+	data[0] = 0x00000000;
+	data[1] = 0x00000000;
+
+	for (i = 0; i < 16 + 2; i += 2) {
+		encrypt_block(P, S, data, data);
+
+		P[i] = data[0];
+		P[i + 1] = data[1];
+	}
+
+	for (i = 0; i < 4; i++) {
+		for (j = 0, count = i * 256; j < 256; j += 2, count += 2) {
+			encrypt_block(P, S, data, data);
+
+			S[count] = data[0];
+			S[count + 1] = data[1];
+		}
+	}
+
+	return 0;
+}
+
+
+/*
+ * turn encryption off
+ */
+void
+dsp_bf_cleanup(struct dsp *dsp)
+{
+	dsp->bf_enable = 0;
+}
diff --git a/drivers/isdn/mISDN/dsp_cmx.c b/drivers/isdn/mISDN/dsp_cmx.c
new file mode 100644
index 000000000..1b73af501
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_cmx.c
@@ -0,0 +1,1960 @@
+/*
+ * Audio crossconnecting/conferrencing (hardware level).
+ *
+ * Copyright 2002 by Andreas Eversberg (jolly@eversberg.eu)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+/*
+ * The process of adding and removing parties to/from a conference:
+ *
+ * There is a chain of struct dsp_conf which has one or more members in a chain
+ * of struct dsp_conf_member.
+ *
+ * After a party is added, the conference is checked for hardware capability.
+ * Also if a party is removed, the conference is checked again.
+ *
+ * There are 3 different solutions: -1 = software, 0 = hardware-crossconnect
+ * 1-n = hardware-conference. The n will give the conference number.
+ *
+ * Depending on the change after removal or insertion of a party, hardware
+ * commands are given.
+ *
+ * The current solution is stored within the struct dsp_conf entry.
+ */
+
+/*
+ * HOW THE CMX WORKS:
+ *
+ * There are 3 types of interaction: One member is alone, in this case only
+ * data flow from upper to lower layer is done.
+ * Two members will also exchange their data so they are crossconnected.
+ * Three or more members will be added in a conference and will hear each
+ * other but will not receive their own speech (echo) if not enabled.
+ *
+ * Features of CMX are:
+ *  - Crossconnecting or even conference, if more than two members are together.
+ *  - Force mixing of transmit data with other crossconnect/conference members.
+ *  - Echo generation to benchmark the delay of audio processing.
+ *  - Use hardware to minimize cpu load, disable FIFO load and minimize delay.
+ *  - Dejittering and clock generation.
+ *
+ * There are 2 buffers:
+ *
+ *
+ * RX-Buffer
+ *                 R             W
+ *                 |             |
+ * ----------------+-------------+-------------------
+ *
+ * The rx-buffer is a ring buffer used to store the received data for each
+ * individual member. This is only the case if data needs to be dejittered
+ * or in case of a conference where different clocks require reclocking.
+ * The transmit-clock (R) will read the buffer.
+ * If the clock overruns the write-pointer, we will have a buffer underrun.
+ * If the write pointer always has a certain distance from the transmit-
+ * clock, we will have a delay. The delay will dynamically be increased and
+ * reduced.
+ *
+ *
+ * TX-Buffer
+ *                  R        W
+ *                  |        |
+ * -----------------+--------+-----------------------
+ *
+ * The tx-buffer is a ring buffer to queue the transmit data from user space
+ * until it will be mixed or sent. There are two pointers, R and W. If the write
+ * pointer W would reach or overrun R, the buffer would overrun. In this case
+ * (some) data is dropped so that it will not overrun.
+ * Additionally a dynamic dejittering can be enabled. this allows data from
+ * user space that have jitter and different clock source.
+ *
+ *
+ * Clock:
+ *
+ * A Clock is not required, if the data source has exactly one clock. In this
+ * case the data source is forwarded to the destination.
+ *
+ * A Clock is required, because the data source
+ *  - has multiple clocks.
+ *  - has no usable clock due to jitter or packet loss (VoIP).
+ * In this case the system's clock is used. The clock resolution depends on
+ * the jiffie resolution.
+ *
+ * If a member joins a conference:
+ *
+ * - If a member joins, its rx_buff is set to silence and change read pointer
+ *   to transmit clock.
+ *
+ * The procedure of received data from card is explained in cmx_receive.
+ * The procedure of received data from user space is explained in cmx_transmit.
+ * The procedure of transmit data to card is cmx_send.
+ *
+ *
+ * Interaction with other features:
+ *
+ * DTMF:
+ * DTMF decoding is done before the data is crossconnected.
+ *
+ * Volume change:
+ * Changing rx-volume is done before the data is crossconnected. The tx-volume
+ * must be changed whenever data is transmitted to the card by the cmx.
+ *
+ * Tones:
+ * If a tone is enabled, it will be processed whenever data is transmitted to
+ * the card. It will replace the tx-data from the user space.
+ * If tones are generated by hardware, this conference member is removed for
+ * this time.
+ *
+ * Disable rx-data:
+ * If cmx is realized in hardware, rx data will be disabled if requested by
+ * the upper layer. If dtmf decoding is done by software and enabled, rx data
+ * will not be disabled but blocked to the upper layer.
+ *
+ * HFC conference engine:
+ * If it is possible to realize all features using hardware, hardware will be
+ * used if not forbidden by control command. Disabling rx-data provides
+ * absolutely traffic free audio processing. (except for the quick 1-frame
+ * upload of a tone loop, only once for a new tone)
+ *
+ */
+
+/* delay.h is required for hw_lock.h */
+
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include "core.h"
+#include "dsp.h"
+/*
+ * debugging of multi party conference,
+ * by using conference even with two members
+ */
+
+/* #define CMX_CONF_DEBUG */
+
+/*#define CMX_DEBUG * massive read/write pointer output */
+/*#define CMX_DELAY_DEBUG * gives rx-buffer delay overview */
+/*#define CMX_TX_DEBUG * massive read/write on tx-buffer with content */
+
+static inline int
+count_list_member(struct list_head *head)
+{
+	int			cnt = 0;
+	struct list_head	*m;
+
+	list_for_each(m, head)
+		cnt++;
+	return cnt;
+}
+
+/*
+ * debug cmx memory structure
+ */
+void
+dsp_cmx_debug(struct dsp *dsp)
+{
+	struct dsp_conf	*conf;
+	struct dsp_conf_member	*member;
+	struct dsp		*odsp;
+
+	printk(KERN_DEBUG "-----Current DSP\n");
+	list_for_each_entry(odsp, &dsp_ilist, list) {
+		printk(KERN_DEBUG "* %s hardecho=%d softecho=%d txmix=%d",
+		       odsp->name, odsp->echo.hardware, odsp->echo.software,
+		       odsp->tx_mix);
+		if (odsp->conf)
+			printk(" (Conf %d)", odsp->conf->id);
+		if (dsp == odsp)
+			printk(" *this*");
+		printk("\n");
+	}
+	printk(KERN_DEBUG "-----Current Conf:\n");
+	list_for_each_entry(conf, &conf_ilist, list) {
+		printk(KERN_DEBUG "* Conf %d (%p)\n", conf->id, conf);
+		list_for_each_entry(member, &conf->mlist, list) {
+			printk(KERN_DEBUG
+			       "  - member = %s (slot_tx %d, bank_tx %d, "
+			       "slot_rx %d, bank_rx %d hfc_conf %d "
+			       "tx_data %d rx_is_off %d)%s\n",
+			       member->dsp->name, member->dsp->pcm_slot_tx,
+			       member->dsp->pcm_bank_tx, member->dsp->pcm_slot_rx,
+			       member->dsp->pcm_bank_rx, member->dsp->hfc_conf,
+			       member->dsp->tx_data, member->dsp->rx_is_off,
+			       (member->dsp == dsp) ? " *this*" : "");
+		}
+	}
+	printk(KERN_DEBUG "-----end\n");
+}
+
+/*
+ * search conference
+ */
+static struct dsp_conf *
+dsp_cmx_search_conf(u32 id)
+{
+	struct dsp_conf *conf;
+
+	if (!id) {
+		printk(KERN_WARNING "%s: conference ID is 0.\n", __func__);
+		return NULL;
+	}
+
+	/* search conference */
+	list_for_each_entry(conf, &conf_ilist, list)
+		if (conf->id == id)
+			return conf;
+
+	return NULL;
+}
+
+
+/*
+ * add member to conference
+ */
+static int
+dsp_cmx_add_conf_member(struct dsp *dsp, struct dsp_conf *conf)
+{
+	struct dsp_conf_member *member;
+
+	if (!conf || !dsp) {
+		printk(KERN_WARNING "%s: conf or dsp is 0.\n", __func__);
+		return -EINVAL;
+	}
+	if (dsp->member) {
+		printk(KERN_WARNING "%s: dsp is already member in a conf.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	if (dsp->conf) {
+		printk(KERN_WARNING "%s: dsp is already in a conf.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	member = kzalloc(sizeof(struct dsp_conf_member), GFP_ATOMIC);
+	if (!member) {
+		printk(KERN_ERR "kzalloc struct dsp_conf_member failed\n");
+		return -ENOMEM;
+	}
+	member->dsp = dsp;
+	/* clear rx buffer */
+	memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
+	dsp->rx_init = 1; /* rx_W and rx_R will be adjusted on first frame */
+	dsp->rx_W = 0;
+	dsp->rx_R = 0;
+
+	list_add_tail(&member->list, &conf->mlist);
+
+	dsp->conf = conf;
+	dsp->member = member;
+
+	return 0;
+}
+
+
+/*
+ * del member from conference
+ */
+int
+dsp_cmx_del_conf_member(struct dsp *dsp)
+{
+	struct dsp_conf_member *member;
+
+	if (!dsp) {
+		printk(KERN_WARNING "%s: dsp is 0.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	if (!dsp->conf) {
+		printk(KERN_WARNING "%s: dsp is not in a conf.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	if (list_empty(&dsp->conf->mlist)) {
+		printk(KERN_WARNING "%s: dsp has linked an empty conf.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	/* find us in conf */
+	list_for_each_entry(member, &dsp->conf->mlist, list) {
+		if (member->dsp == dsp) {
+			list_del(&member->list);
+			dsp->conf = NULL;
+			dsp->member = NULL;
+			kfree(member);
+			return 0;
+		}
+	}
+	printk(KERN_WARNING
+	       "%s: dsp is not present in its own conf_member list.\n",
+	       __func__);
+
+	return -EINVAL;
+}
+
+
+/*
+ * new conference
+ */
+static struct dsp_conf
+*dsp_cmx_new_conf(u32 id)
+{
+	struct dsp_conf *conf;
+
+	if (!id) {
+		printk(KERN_WARNING "%s: id is 0.\n",
+		       __func__);
+		return NULL;
+	}
+
+	conf = kzalloc(sizeof(struct dsp_conf), GFP_ATOMIC);
+	if (!conf) {
+		printk(KERN_ERR "kzalloc struct dsp_conf failed\n");
+		return NULL;
+	}
+	INIT_LIST_HEAD(&conf->mlist);
+	conf->id = id;
+
+	list_add_tail(&conf->list, &conf_ilist);
+
+	return conf;
+}
+
+
+/*
+ * del conference
+ */
+int
+dsp_cmx_del_conf(struct dsp_conf *conf)
+{
+	if (!conf) {
+		printk(KERN_WARNING "%s: conf is null.\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	if (!list_empty(&conf->mlist)) {
+		printk(KERN_WARNING "%s: conf not empty.\n",
+		       __func__);
+		return -EINVAL;
+	}
+	list_del(&conf->list);
+	kfree(conf);
+
+	return 0;
+}
+
+
+/*
+ * send HW message to hfc card
+ */
+static void
+dsp_cmx_hw_message(struct dsp *dsp, u32 message, u32 param1, u32 param2,
+		   u32 param3, u32 param4)
+{
+	struct mISDN_ctrl_req cq;
+
+	memset(&cq, 0, sizeof(cq));
+	cq.op = message;
+	cq.p1 = param1 | (param2 << 8);
+	cq.p2 = param3 | (param4 << 8);
+	if (dsp->ch.peer)
+		dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq);
+}
+
+
+/*
+ * do hardware update and set the software/hardware flag
+ *
+ * either a conference or a dsp instance can be given
+ * if only dsp instance is given, the instance is not associated with a conf
+ * and therefore removed. if a conference is given, the dsp is expected to
+ * be member of that conference.
+ */
+void
+dsp_cmx_hardware(struct dsp_conf *conf, struct dsp *dsp)
+{
+	struct dsp_conf_member	*member, *nextm;
+	struct dsp		*finddsp;
+	int		memb = 0, i, ii, i1, i2;
+	int		freeunits[8];
+	u_char		freeslots[256];
+	int		same_hfc = -1, same_pcm = -1, current_conf = -1,
+		all_conf = 1, tx_data = 0;
+
+	/* dsp gets updated (no conf) */
+	if (!conf) {
+		if (!dsp)
+			return;
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG "%s checking dsp %s\n",
+			       __func__, dsp->name);
+	one_member:
+		/* remove HFC conference if enabled */
+		if (dsp->hfc_conf >= 0) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s removing %s from HFC conf %d "
+				       "because dsp is split\n", __func__,
+				       dsp->name, dsp->hfc_conf);
+			dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_CONF_SPLIT,
+					   0, 0, 0, 0);
+			dsp->hfc_conf = -1;
+		}
+		/* process hw echo */
+		if (dsp->features.pcm_banks < 1)
+			return;
+		if (!dsp->echo.software && !dsp->echo.hardware) {
+			/* NO ECHO: remove PCM slot if assigned */
+			if (dsp->pcm_slot_tx >= 0 || dsp->pcm_slot_rx >= 0) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG "%s removing %s from"
+					       " PCM slot %d (TX) %d (RX) because"
+					       " dsp is split (no echo)\n",
+					       __func__, dsp->name,
+					       dsp->pcm_slot_tx, dsp->pcm_slot_rx);
+				dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_DISC,
+						   0, 0, 0, 0);
+				dsp->pcm_slot_tx = -1;
+				dsp->pcm_bank_tx = -1;
+				dsp->pcm_slot_rx = -1;
+				dsp->pcm_bank_rx = -1;
+			}
+			return;
+		}
+		/* echo is enabled, find out if we use soft or hardware */
+		dsp->echo.software = dsp->tx_data;
+		dsp->echo.hardware = 0;
+		/* ECHO: already echo */
+		if (dsp->pcm_slot_tx >= 0 && dsp->pcm_slot_rx < 0 &&
+		    dsp->pcm_bank_tx == 2 && dsp->pcm_bank_rx == 2) {
+			dsp->echo.hardware = 1;
+			return;
+		}
+		/* ECHO: if slot already assigned */
+		if (dsp->pcm_slot_tx >= 0) {
+			dsp->pcm_slot_rx = dsp->pcm_slot_tx;
+			dsp->pcm_bank_tx = 2; /* 2 means loop */
+			dsp->pcm_bank_rx = 2;
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s refresh %s for echo using slot %d\n",
+				       __func__, dsp->name,
+				       dsp->pcm_slot_tx);
+			dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   dsp->pcm_slot_tx, 2, dsp->pcm_slot_rx, 2);
+			dsp->echo.hardware = 1;
+			return;
+		}
+		/* ECHO: find slot */
+		dsp->pcm_slot_tx = -1;
+		dsp->pcm_slot_rx = -1;
+		memset(freeslots, 1, sizeof(freeslots));
+		list_for_each_entry(finddsp, &dsp_ilist, list) {
+			if (finddsp->features.pcm_id == dsp->features.pcm_id) {
+				if (finddsp->pcm_slot_rx >= 0 &&
+				    finddsp->pcm_slot_rx < sizeof(freeslots))
+					freeslots[finddsp->pcm_slot_rx] = 0;
+				if (finddsp->pcm_slot_tx >= 0 &&
+				    finddsp->pcm_slot_tx < sizeof(freeslots))
+					freeslots[finddsp->pcm_slot_tx] = 0;
+			}
+		}
+		i = 0;
+		ii = dsp->features.pcm_slots;
+		while (i < ii) {
+			if (freeslots[i])
+				break;
+			i++;
+		}
+		if (i == ii) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s no slot available for echo\n",
+				       __func__);
+			/* no more slots available */
+			dsp->echo.software = 1;
+			return;
+		}
+		/* assign free slot */
+		dsp->pcm_slot_tx = i;
+		dsp->pcm_slot_rx = i;
+		dsp->pcm_bank_tx = 2; /* loop */
+		dsp->pcm_bank_rx = 2;
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "%s assign echo for %s using slot %d\n",
+			       __func__, dsp->name, dsp->pcm_slot_tx);
+		dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_CONN,
+				   dsp->pcm_slot_tx, 2, dsp->pcm_slot_rx, 2);
+		dsp->echo.hardware = 1;
+		return;
+	}
+
+	/* conf gets updated (all members) */
+	if (dsp_debug & DEBUG_DSP_CMX)
+		printk(KERN_DEBUG "%s checking conference %d\n",
+		       __func__, conf->id);
+
+	if (list_empty(&conf->mlist)) {
+		printk(KERN_ERR "%s: conference without members\n",
+		       __func__);
+		return;
+	}
+	member = list_entry(conf->mlist.next, struct dsp_conf_member, list);
+	same_hfc = member->dsp->features.hfc_id;
+	same_pcm = member->dsp->features.pcm_id;
+	/* check all members in our conference */
+	list_for_each_entry(member, &conf->mlist, list) {
+		/* check if member uses mixing */
+		if (member->dsp->tx_mix) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "tx_mix is turned on\n", __func__,
+				       member->dsp->name);
+		conf_software:
+			list_for_each_entry(member, &conf->mlist, list) {
+				dsp = member->dsp;
+				/* remove HFC conference if enabled */
+				if (dsp->hfc_conf >= 0) {
+					if (dsp_debug & DEBUG_DSP_CMX)
+						printk(KERN_DEBUG
+						       "%s removing %s from HFC "
+						       "conf %d because not "
+						       "possible with hardware\n",
+						       __func__,
+						       dsp->name,
+						       dsp->hfc_conf);
+					dsp_cmx_hw_message(dsp,
+							   MISDN_CTRL_HFC_CONF_SPLIT,
+							   0, 0, 0, 0);
+					dsp->hfc_conf = -1;
+				}
+				/* remove PCM slot if assigned */
+				if (dsp->pcm_slot_tx >= 0 ||
+				    dsp->pcm_slot_rx >= 0) {
+					if (dsp_debug & DEBUG_DSP_CMX)
+						printk(KERN_DEBUG "%s removing "
+						       "%s from PCM slot %d (TX)"
+						       " slot %d (RX) because not"
+						       " possible with hardware\n",
+						       __func__,
+						       dsp->name,
+						       dsp->pcm_slot_tx,
+						       dsp->pcm_slot_rx);
+					dsp_cmx_hw_message(dsp,
+							   MISDN_CTRL_HFC_PCM_DISC,
+							   0, 0, 0, 0);
+					dsp->pcm_slot_tx = -1;
+					dsp->pcm_bank_tx = -1;
+					dsp->pcm_slot_rx = -1;
+					dsp->pcm_bank_rx = -1;
+				}
+			}
+			conf->hardware = 0;
+			conf->software = 1;
+			return;
+		}
+		/* check if member has echo turned on */
+		if (member->dsp->echo.hardware || member->dsp->echo.software) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "echo is turned on\n", __func__,
+				       member->dsp->name);
+			goto conf_software;
+		}
+		/* check if member has tx_mix turned on */
+		if (member->dsp->tx_mix) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "tx_mix is turned on\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* check if member changes volume at an not suppoted level */
+		if (member->dsp->tx_volume) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "tx_volume is changed\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		if (member->dsp->rx_volume) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "rx_volume is changed\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* check if tx-data turned on */
+		if (member->dsp->tx_data) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s tx_data is turned on\n",
+				       __func__, member->dsp->name);
+			tx_data = 1;
+		}
+		/* check if pipeline exists */
+		if (member->dsp->pipeline.inuse) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "pipeline exists\n", __func__,
+				       member->dsp->name);
+			goto conf_software;
+		}
+		/* check if encryption is enabled */
+		if (member->dsp->bf_enable) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG "%s dsp %s cannot form a "
+				       "conf, because encryption is enabled\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* check if member is on a card with PCM support */
+		if (member->dsp->features.pcm_id < 0) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "dsp has no PCM bus\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* check if relations are on the same PCM bus */
+		if (member->dsp->features.pcm_id != same_pcm) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s dsp %s cannot form a conf, because "
+				       "dsp is on a different PCM bus than the "
+				       "first dsp\n",
+				       __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* determine if members are on the same hfc chip */
+		if (same_hfc != member->dsp->features.hfc_id)
+			same_hfc = -1;
+		/* if there are members already in a conference */
+		if (current_conf < 0 && member->dsp->hfc_conf >= 0)
+			current_conf = member->dsp->hfc_conf;
+		/* if any member is not in a conference */
+		if (member->dsp->hfc_conf < 0)
+			all_conf = 0;
+
+		memb++;
+	}
+
+	/* if no member, this is an error */
+	if (memb < 1)
+		return;
+
+	/* one member */
+	if (memb == 1) {
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "%s conf %d cannot form a HW conference, "
+			       "because dsp is alone\n", __func__, conf->id);
+		conf->hardware = 0;
+		conf->software = 0;
+		member = list_entry(conf->mlist.next, struct dsp_conf_member,
+				    list);
+		dsp = member->dsp;
+		goto one_member;
+	}
+
+	/*
+	 * ok, now we are sure that all members are on the same pcm.
+	 * now we will see if we have only two members, so we can do
+	 * crossconnections, which don't have any limitations.
+	 */
+
+	/* if we have only two members */
+	if (memb == 2) {
+		member = list_entry(conf->mlist.next, struct dsp_conf_member,
+				    list);
+		nextm = list_entry(member->list.next, struct dsp_conf_member,
+				   list);
+		/* remove HFC conference if enabled */
+		if (member->dsp->hfc_conf >= 0) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s removing %s from HFC conf %d because "
+				       "two parties require only a PCM slot\n",
+				       __func__, member->dsp->name,
+				       member->dsp->hfc_conf);
+			dsp_cmx_hw_message(member->dsp,
+					   MISDN_CTRL_HFC_CONF_SPLIT, 0, 0, 0, 0);
+			member->dsp->hfc_conf = -1;
+		}
+		if (nextm->dsp->hfc_conf >= 0) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s removing %s from HFC conf %d because "
+				       "two parties require only a PCM slot\n",
+				       __func__, nextm->dsp->name,
+				       nextm->dsp->hfc_conf);
+			dsp_cmx_hw_message(nextm->dsp,
+					   MISDN_CTRL_HFC_CONF_SPLIT, 0, 0, 0, 0);
+			nextm->dsp->hfc_conf = -1;
+		}
+		/* if members have two banks (and not on the same chip) */
+		if (member->dsp->features.pcm_banks > 1 &&
+		    nextm->dsp->features.pcm_banks > 1 &&
+		    member->dsp->features.hfc_id !=
+		    nextm->dsp->features.hfc_id) {
+			/* if both members have same slots with crossed banks */
+			if (member->dsp->pcm_slot_tx >= 0 &&
+			    member->dsp->pcm_slot_rx >= 0 &&
+			    nextm->dsp->pcm_slot_tx >= 0 &&
+			    nextm->dsp->pcm_slot_rx >= 0 &&
+			    nextm->dsp->pcm_slot_tx ==
+			    member->dsp->pcm_slot_rx &&
+			    nextm->dsp->pcm_slot_rx ==
+			    member->dsp->pcm_slot_tx &&
+			    nextm->dsp->pcm_slot_tx ==
+			    member->dsp->pcm_slot_tx &&
+			    member->dsp->pcm_bank_tx !=
+			    member->dsp->pcm_bank_rx &&
+			    nextm->dsp->pcm_bank_tx !=
+			    nextm->dsp->pcm_bank_rx) {
+				/* all members have same slot */
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s dsp %s & %s stay joined on "
+					       "PCM slot %d bank %d (TX) bank %d "
+					       "(RX) (on different chips)\n",
+					       __func__,
+					       member->dsp->name,
+					       nextm->dsp->name,
+					       member->dsp->pcm_slot_tx,
+					       member->dsp->pcm_bank_tx,
+					       member->dsp->pcm_bank_rx);
+				conf->hardware = 1;
+				conf->software = tx_data;
+				return;
+			}
+			/* find a new slot */
+			memset(freeslots, 1, sizeof(freeslots));
+			list_for_each_entry(dsp, &dsp_ilist, list) {
+				if (dsp != member->dsp &&
+				    dsp != nextm->dsp &&
+				    member->dsp->features.pcm_id ==
+				    dsp->features.pcm_id) {
+					if (dsp->pcm_slot_rx >= 0 &&
+					    dsp->pcm_slot_rx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_rx] = 0;
+					if (dsp->pcm_slot_tx >= 0 &&
+					    dsp->pcm_slot_tx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_tx] = 0;
+				}
+			}
+			i = 0;
+			ii = member->dsp->features.pcm_slots;
+			while (i < ii) {
+				if (freeslots[i])
+					break;
+				i++;
+			}
+			if (i == ii) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s no slot available for "
+					       "%s & %s\n", __func__,
+					       member->dsp->name,
+					       nextm->dsp->name);
+				/* no more slots available */
+				goto conf_software;
+			}
+			/* assign free slot */
+			member->dsp->pcm_slot_tx = i;
+			member->dsp->pcm_slot_rx = i;
+			nextm->dsp->pcm_slot_tx = i;
+			nextm->dsp->pcm_slot_rx = i;
+			member->dsp->pcm_bank_rx = 0;
+			member->dsp->pcm_bank_tx = 1;
+			nextm->dsp->pcm_bank_rx = 1;
+			nextm->dsp->pcm_bank_tx = 0;
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s adding %s & %s to new PCM slot %d "
+				       "(TX and RX on different chips) because "
+				       "both members have not same slots\n",
+				       __func__,
+				       member->dsp->name,
+				       nextm->dsp->name,
+				       member->dsp->pcm_slot_tx);
+			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   member->dsp->pcm_slot_tx, member->dsp->pcm_bank_tx,
+					   member->dsp->pcm_slot_rx, member->dsp->pcm_bank_rx);
+			dsp_cmx_hw_message(nextm->dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   nextm->dsp->pcm_slot_tx, nextm->dsp->pcm_bank_tx,
+					   nextm->dsp->pcm_slot_rx, nextm->dsp->pcm_bank_rx);
+			conf->hardware = 1;
+			conf->software = tx_data;
+			return;
+			/* if members have one bank (or on the same chip) */
+		} else {
+			/* if both members have different crossed slots */
+			if (member->dsp->pcm_slot_tx >= 0 &&
+			    member->dsp->pcm_slot_rx >= 0 &&
+			    nextm->dsp->pcm_slot_tx >= 0 &&
+			    nextm->dsp->pcm_slot_rx >= 0 &&
+			    nextm->dsp->pcm_slot_tx ==
+			    member->dsp->pcm_slot_rx &&
+			    nextm->dsp->pcm_slot_rx ==
+			    member->dsp->pcm_slot_tx &&
+			    member->dsp->pcm_slot_tx !=
+			    member->dsp->pcm_slot_rx &&
+			    member->dsp->pcm_bank_tx == 0 &&
+			    member->dsp->pcm_bank_rx == 0 &&
+			    nextm->dsp->pcm_bank_tx == 0 &&
+			    nextm->dsp->pcm_bank_rx == 0) {
+				/* all members have same slot */
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s dsp %s & %s stay joined on PCM "
+					       "slot %d (TX) %d (RX) on same chip "
+					       "or one bank PCM)\n", __func__,
+					       member->dsp->name,
+					       nextm->dsp->name,
+					       member->dsp->pcm_slot_tx,
+					       member->dsp->pcm_slot_rx);
+				conf->hardware = 1;
+				conf->software = tx_data;
+				return;
+			}
+			/* find two new slot */
+			memset(freeslots, 1, sizeof(freeslots));
+			list_for_each_entry(dsp, &dsp_ilist, list) {
+				if (dsp != member->dsp &&
+				    dsp != nextm->dsp &&
+				    member->dsp->features.pcm_id ==
+				    dsp->features.pcm_id) {
+					if (dsp->pcm_slot_rx >= 0 &&
+					    dsp->pcm_slot_rx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_rx] = 0;
+					if (dsp->pcm_slot_tx >= 0 &&
+					    dsp->pcm_slot_tx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_tx] = 0;
+				}
+			}
+			i1 = 0;
+			ii = member->dsp->features.pcm_slots;
+			while (i1 < ii) {
+				if (freeslots[i1])
+					break;
+				i1++;
+			}
+			if (i1 == ii) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s no slot available "
+					       "for %s & %s\n", __func__,
+					       member->dsp->name,
+					       nextm->dsp->name);
+				/* no more slots available */
+				goto conf_software;
+			}
+			i2 = i1 + 1;
+			while (i2 < ii) {
+				if (freeslots[i2])
+					break;
+				i2++;
+			}
+			if (i2 == ii) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s no slot available "
+					       "for %s & %s\n",
+					       __func__,
+					       member->dsp->name,
+					       nextm->dsp->name);
+				/* no more slots available */
+				goto conf_software;
+			}
+			/* assign free slots */
+			member->dsp->pcm_slot_tx = i1;
+			member->dsp->pcm_slot_rx = i2;
+			nextm->dsp->pcm_slot_tx = i2;
+			nextm->dsp->pcm_slot_rx = i1;
+			member->dsp->pcm_bank_rx = 0;
+			member->dsp->pcm_bank_tx = 0;
+			nextm->dsp->pcm_bank_rx = 0;
+			nextm->dsp->pcm_bank_tx = 0;
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s adding %s & %s to new PCM slot %d "
+				       "(TX) %d (RX) on same chip or one bank "
+				       "PCM, because both members have not "
+				       "crossed slots\n", __func__,
+				       member->dsp->name,
+				       nextm->dsp->name,
+				       member->dsp->pcm_slot_tx,
+				       member->dsp->pcm_slot_rx);
+			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   member->dsp->pcm_slot_tx, member->dsp->pcm_bank_tx,
+					   member->dsp->pcm_slot_rx, member->dsp->pcm_bank_rx);
+			dsp_cmx_hw_message(nextm->dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   nextm->dsp->pcm_slot_tx, nextm->dsp->pcm_bank_tx,
+					   nextm->dsp->pcm_slot_rx, nextm->dsp->pcm_bank_rx);
+			conf->hardware = 1;
+			conf->software = tx_data;
+			return;
+		}
+	}
+
+	/*
+	 * if we have more than two, we may check if we have a conference
+	 * unit available on the chip. also all members must be on the same
+	 */
+
+	/* if not the same HFC chip */
+	if (same_hfc < 0) {
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "%s conference %d cannot be formed, because "
+			       "members are on different chips or not "
+			       "on HFC chip\n",
+			       __func__, conf->id);
+		goto conf_software;
+	}
+
+	/* for more than two members.. */
+
+	/* if all members already have the same conference */
+	if (all_conf) {
+		conf->hardware = 1;
+		conf->software = tx_data;
+		return;
+	}
+
+	/*
+	 * if there is an existing conference, but not all members have joined
+	 */
+	if (current_conf >= 0) {
+	join_members:
+		list_for_each_entry(member, &conf->mlist, list) {
+			/* if no conference engine on our chip, change to
+			 * software */
+			if (!member->dsp->features.hfc_conf)
+				goto conf_software;
+			/* in case of hdlc, change to software */
+			if (member->dsp->hdlc)
+				goto conf_software;
+			/* join to current conference */
+			if (member->dsp->hfc_conf == current_conf)
+				continue;
+			/* get a free timeslot first */
+			memset(freeslots, 1, sizeof(freeslots));
+			list_for_each_entry(dsp, &dsp_ilist, list) {
+				/*
+				 * not checking current member, because
+				 * slot will be overwritten.
+				 */
+				if (
+					dsp != member->dsp &&
+					/* dsp must be on the same PCM */
+					member->dsp->features.pcm_id ==
+					dsp->features.pcm_id) {
+					/* dsp must be on a slot */
+					if (dsp->pcm_slot_tx >= 0 &&
+					    dsp->pcm_slot_tx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_tx] = 0;
+					if (dsp->pcm_slot_rx >= 0 &&
+					    dsp->pcm_slot_rx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_rx] = 0;
+				}
+			}
+			i = 0;
+			ii = member->dsp->features.pcm_slots;
+			while (i < ii) {
+				if (freeslots[i])
+					break;
+				i++;
+			}
+			if (i == ii) {
+				/* no more slots available */
+				if (dsp_debug & DEBUG_DSP_CMX)
+					printk(KERN_DEBUG
+					       "%s conference %d cannot be formed,"
+					       " because no slot free\n",
+					       __func__, conf->id);
+				goto conf_software;
+			}
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "%s changing dsp %s to HW conference "
+				       "%d slot %d\n", __func__,
+				       member->dsp->name, current_conf, i);
+			/* assign free slot & set PCM & join conf */
+			member->dsp->pcm_slot_tx = i;
+			member->dsp->pcm_slot_rx = i;
+			member->dsp->pcm_bank_tx = 2; /* loop */
+			member->dsp->pcm_bank_rx = 2;
+			member->dsp->hfc_conf = current_conf;
+			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
+					   i, 2, i, 2);
+			dsp_cmx_hw_message(member->dsp,
+					   MISDN_CTRL_HFC_CONF_JOIN, current_conf, 0, 0, 0);
+		}
+		conf->hardware = 1;
+		conf->software = tx_data;
+		return;
+	}
+
+	/*
+	 * no member is in a conference yet, so we find a free one
+	 */
+	memset(freeunits, 1, sizeof(freeunits));
+	list_for_each_entry(dsp, &dsp_ilist, list) {
+		/* dsp must be on the same chip */
+		if (dsp->features.hfc_id == same_hfc &&
+		    /* dsp must have joined a HW conference */
+		    dsp->hfc_conf >= 0 &&
+		    /* slot must be within range */
+		    dsp->hfc_conf < 8)
+			freeunits[dsp->hfc_conf] = 0;
+	}
+	i = 0;
+	ii = 8;
+	while (i < ii) {
+		if (freeunits[i])
+			break;
+		i++;
+	}
+	if (i == ii) {
+		/* no more conferences available */
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "%s conference %d cannot be formed, because "
+			       "no conference number free\n",
+			       __func__, conf->id);
+		goto conf_software;
+	}
+	/* join all members */
+	current_conf = i;
+	goto join_members;
+}
+
+
+/*
+ * conf_id != 0: join or change conference
+ * conf_id == 0: split from conference if not already
+ */
+int
+dsp_cmx_conf(struct dsp *dsp, u32 conf_id)
+{
+	int err;
+	struct dsp_conf *conf;
+	struct dsp_conf_member	*member;
+
+	/* if conference doesn't change */
+	if (dsp->conf_id == conf_id)
+		return 0;
+
+	/* first remove us from current conf */
+	if (dsp->conf_id) {
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG "removing us from conference %d\n",
+			       dsp->conf->id);
+		/* remove us from conf */
+		conf = dsp->conf;
+		err = dsp_cmx_del_conf_member(dsp);
+		if (err)
+			return err;
+		dsp->conf_id = 0;
+
+		/* update hardware */
+		dsp_cmx_hardware(NULL, dsp);
+
+		/* conf now empty? */
+		if (list_empty(&conf->mlist)) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "conference is empty, so we remove it.\n");
+			err = dsp_cmx_del_conf(conf);
+			if (err)
+				return err;
+		} else {
+			/* update members left on conf */
+			dsp_cmx_hardware(conf, NULL);
+		}
+	}
+
+	/* if split */
+	if (!conf_id)
+		return 0;
+
+	/* now add us to conf */
+	if (dsp_debug & DEBUG_DSP_CMX)
+		printk(KERN_DEBUG "searching conference %d\n",
+		       conf_id);
+	conf = dsp_cmx_search_conf(conf_id);
+	if (!conf) {
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "conference doesn't exist yet, creating.\n");
+		/* the conference doesn't exist, so we create */
+		conf = dsp_cmx_new_conf(conf_id);
+		if (!conf)
+			return -EINVAL;
+	} else if (!list_empty(&conf->mlist)) {
+		member = list_entry(conf->mlist.next, struct dsp_conf_member,
+				    list);
+		if (dsp->hdlc && !member->dsp->hdlc) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "cannot join transparent conference.\n");
+			return -EINVAL;
+		}
+		if (!dsp->hdlc && member->dsp->hdlc) {
+			if (dsp_debug & DEBUG_DSP_CMX)
+				printk(KERN_DEBUG
+				       "cannot join hdlc conference.\n");
+			return -EINVAL;
+		}
+	}
+	/* add conference member */
+	err = dsp_cmx_add_conf_member(dsp, conf);
+	if (err)
+		return err;
+	dsp->conf_id = conf_id;
+
+	/* if we are alone, we do nothing! */
+	if (list_empty(&conf->mlist)) {
+		if (dsp_debug & DEBUG_DSP_CMX)
+			printk(KERN_DEBUG
+			       "we are alone in this conference, so exit.\n");
+		/* update hardware */
+		dsp_cmx_hardware(NULL, dsp);
+		return 0;
+	}
+
+	/* update members on conf */
+	dsp_cmx_hardware(conf, NULL);
+
+	return 0;
+}
+
+#ifdef CMX_DELAY_DEBUG
+int delaycount;
+static void
+showdelay(struct dsp *dsp, int samples, int delay)
+{
+	char bar[] = "--------------------------------------------------|";
+	int sdelay;
+
+	delaycount += samples;
+	if (delaycount < 8000)
+		return;
+	delaycount = 0;
+
+	sdelay = delay * 50 / (dsp_poll << 2);
+
+	printk(KERN_DEBUG "DELAY (%s) %3d >%s\n", dsp->name, delay,
+	       sdelay > 50 ? "..." : bar + 50 - sdelay);
+}
+#endif
+
+/*
+ * audio data is received from card
+ */
+void
+dsp_cmx_receive(struct dsp *dsp, struct sk_buff *skb)
+{
+	u8 *d, *p;
+	int len = skb->len;
+	struct mISDNhead *hh = mISDN_HEAD_P(skb);
+	int w, i, ii;
+
+	/* check if we have sompen */
+	if (len < 1)
+		return;
+
+	/* half of the buffer should be larger than maximum packet size */
+	if (len >= CMX_BUFF_HALF) {
+		printk(KERN_ERR
+		       "%s line %d: packet from card is too large (%d bytes). "
+		       "please make card send smaller packets OR increase "
+		       "CMX_BUFF_SIZE\n", __FILE__, __LINE__, len);
+		return;
+	}
+
+	/*
+	 * initialize pointers if not already -
+	 * also add delay if requested by PH_SIGNAL
+	 */
+	if (dsp->rx_init) {
+		dsp->rx_init = 0;
+		if (dsp->features.unordered) {
+			dsp->rx_R = (hh->id & CMX_BUFF_MASK);
+			if (dsp->cmx_delay)
+				dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
+					& CMX_BUFF_MASK;
+			else
+				dsp->rx_W = (dsp->rx_R + (dsp_poll >> 1))
+					& CMX_BUFF_MASK;
+		} else {
+			dsp->rx_R = 0;
+			if (dsp->cmx_delay)
+				dsp->rx_W = dsp->cmx_delay;
+			else
+				dsp->rx_W = dsp_poll >> 1;
+		}
+	}
+	/* if frame contains time code, write directly */
+	if (dsp->features.unordered) {
+		dsp->rx_W = (hh->id & CMX_BUFF_MASK);
+		/* printk(KERN_DEBUG "%s %08x\n", dsp->name, hh->id); */
+	}
+	/*
+	 * if we underrun (or maybe overrun),
+	 * we set our new read pointer, and write silence to buffer
+	 */
+	if (((dsp->rx_W-dsp->rx_R) & CMX_BUFF_MASK) >= CMX_BUFF_HALF) {
+		if (dsp_debug & DEBUG_DSP_CLOCK)
+			printk(KERN_DEBUG
+			       "cmx_receive(dsp=%lx): UNDERRUN (or overrun the "
+			       "maximum delay), adjusting read pointer! "
+			       "(inst %s)\n", (u_long)dsp, dsp->name);
+		/* flush rx buffer and set delay to dsp_poll / 2 */
+		if (dsp->features.unordered) {
+			dsp->rx_R = (hh->id & CMX_BUFF_MASK);
+			if (dsp->cmx_delay)
+				dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
+					& CMX_BUFF_MASK;
+			else
+				dsp->rx_W = (dsp->rx_R + (dsp_poll >> 1))
+					& CMX_BUFF_MASK;
+		} else {
+			dsp->rx_R = 0;
+			if (dsp->cmx_delay)
+				dsp->rx_W = dsp->cmx_delay;
+			else
+				dsp->rx_W = dsp_poll >> 1;
+		}
+		memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
+	}
+	/* if we have reached double delay, jump back to middle */
+	if (dsp->cmx_delay)
+		if (((dsp->rx_W - dsp->rx_R) & CMX_BUFF_MASK) >=
+		    (dsp->cmx_delay << 1)) {
+			if (dsp_debug & DEBUG_DSP_CLOCK)
+				printk(KERN_DEBUG
+				       "cmx_receive(dsp=%lx): OVERRUN (because "
+				       "twice the delay is reached), adjusting "
+				       "read pointer! (inst %s)\n",
+				       (u_long)dsp, dsp->name);
+			/* flush buffer */
+			if (dsp->features.unordered) {
+				dsp->rx_R = (hh->id & CMX_BUFF_MASK);
+				dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
+					& CMX_BUFF_MASK;
+			} else {
+				dsp->rx_R = 0;
+				dsp->rx_W = dsp->cmx_delay;
+			}
+			memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
+		}
+
+	/* show where to write */
+#ifdef CMX_DEBUG
+	printk(KERN_DEBUG
+	       "cmx_receive(dsp=%lx): rx_R(dsp)=%05x rx_W(dsp)=%05x len=%d %s\n",
+	       (u_long)dsp, dsp->rx_R, dsp->rx_W, len, dsp->name);
+#endif
+
+	/* write data into rx_buffer */
+	p = skb->data;
+	d = dsp->rx_buff;
+	w = dsp->rx_W;
+	i = 0;
+	ii = len;
+	while (i < ii) {
+		d[w++ & CMX_BUFF_MASK] = *p++;
+		i++;
+	}
+
+	/* increase write-pointer */
+	dsp->rx_W = ((dsp->rx_W + len) & CMX_BUFF_MASK);
+#ifdef CMX_DELAY_DEBUG
+	showdelay(dsp, len, (dsp->rx_W-dsp->rx_R) & CMX_BUFF_MASK);
+#endif
+}
+
+
+/*
+ * send (mixed) audio data to card and control jitter
+ */
+static void
+dsp_cmx_send_member(struct dsp *dsp, int len, s32 *c, int members)
+{
+	struct dsp_conf *conf = dsp->conf;
+	struct dsp *member, *other;
+	register s32 sample;
+	u8 *d, *p, *q, *o_q;
+	struct sk_buff *nskb, *txskb;
+	int r, rr, t, tt, o_r, o_rr;
+	int preload = 0;
+	struct mISDNhead *hh, *thh;
+	int tx_data_only = 0;
+
+	/* don't process if: */
+	if (!dsp->b_active) { /* if not active */
+		dsp->last_tx = 0;
+		return;
+	}
+	if (((dsp->conf && dsp->conf->hardware) || /* hardware conf */
+	     dsp->echo.hardware) && /* OR hardware echo */
+	    dsp->tx_R == dsp->tx_W && /* AND no tx-data */
+	    !(dsp->tone.tone && dsp->tone.software)) { /* AND not soft tones */
+		if (!dsp->tx_data) { /* no tx_data for user space required */
+			dsp->last_tx = 0;
+			return;
+		}
+		if (dsp->conf && dsp->conf->software && dsp->conf->hardware)
+			tx_data_only = 1;
+		if (dsp->echo.software && dsp->echo.hardware)
+			tx_data_only = 1;
+	}
+
+#ifdef CMX_DEBUG
+	printk(KERN_DEBUG
+	       "SEND members=%d dsp=%s, conf=%p, rx_R=%05x rx_W=%05x\n",
+	       members, dsp->name, conf, dsp->rx_R, dsp->rx_W);
+#endif
+
+	/* preload if we have delay set */
+	if (dsp->cmx_delay && !dsp->last_tx) {
+		preload = len;
+		if (preload < 128)
+			preload = 128;
+	}
+
+	/* PREPARE RESULT */
+	nskb = mI_alloc_skb(len + preload, GFP_ATOMIC);
+	if (!nskb) {
+		printk(KERN_ERR
+		       "FATAL ERROR in mISDN_dsp.o: cannot alloc %d bytes\n",
+		       len + preload);
+		return;
+	}
+	hh = mISDN_HEAD_P(nskb);
+	hh->prim = PH_DATA_REQ;
+	hh->id = 0;
+	dsp->last_tx = 1;
+
+	/* set pointers, indexes and stuff */
+	member = dsp;
+	p = dsp->tx_buff; /* transmit data */
+	q = dsp->rx_buff; /* received data */
+	d = skb_put(nskb, preload + len); /* result */
+	t = dsp->tx_R; /* tx-pointers */
+	tt = dsp->tx_W;
+	r = dsp->rx_R; /* rx-pointers */
+	rr = (r + len) & CMX_BUFF_MASK;
+
+	/* preload with silence, if required */
+	if (preload) {
+		memset(d, dsp_silence, preload);
+		d += preload;
+	}
+
+	/* PROCESS TONES/TX-DATA ONLY */
+	if (dsp->tone.tone && dsp->tone.software) {
+		/* -> copy tone */
+		dsp_tone_copy(dsp, d, len);
+		dsp->tx_R = 0; /* clear tx buffer */
+		dsp->tx_W = 0;
+		goto send_packet;
+	}
+	/* if we have tx-data but do not use mixing */
+	if (!dsp->tx_mix && t != tt) {
+		/* -> send tx-data and continue when not enough */
+#ifdef CMX_TX_DEBUG
+		sprintf(debugbuf, "TX sending (%04x-%04x)%p: ", t, tt, p);
+#endif
+		while (r != rr && t != tt) {
+#ifdef CMX_TX_DEBUG
+			if (strlen(debugbuf) < 48)
+				sprintf(debugbuf + strlen(debugbuf), " %02x",
+					p[t]);
+#endif
+			*d++ = p[t]; /* write tx_buff */
+			t = (t + 1) & CMX_BUFF_MASK;
+			r = (r + 1) & CMX_BUFF_MASK;
+		}
+		if (r == rr) {
+			dsp->tx_R = t;
+#ifdef CMX_TX_DEBUG
+			printk(KERN_DEBUG "%s\n", debugbuf);
+#endif
+			goto send_packet;
+		}
+	}
+#ifdef CMX_TX_DEBUG
+	printk(KERN_DEBUG "%s\n", debugbuf);
+#endif
+
+	/* PROCESS DATA (one member / no conf) */
+	if (!conf || members <= 1) {
+		/* -> if echo is NOT enabled */
+		if (!dsp->echo.software) {
+			/* -> send tx-data if available or use 0-volume */
+			while (r != rr && t != tt) {
+				*d++ = p[t]; /* write tx_buff */
+				t = (t + 1) & CMX_BUFF_MASK;
+				r = (r + 1) & CMX_BUFF_MASK;
+			}
+			if (r != rr) {
+				if (dsp_debug & DEBUG_DSP_CLOCK)
+					printk(KERN_DEBUG "%s: RX empty\n",
+					       __func__);
+				memset(d, dsp_silence, (rr - r) & CMX_BUFF_MASK);
+			}
+			/* -> if echo is enabled */
+		} else {
+			/*
+			 * -> mix tx-data with echo if available,
+			 * or use echo only
+			 */
+			while (r != rr && t != tt) {
+				*d++ = dsp_audio_mix_law[(p[t] << 8) | q[r]];
+				t = (t + 1) & CMX_BUFF_MASK;
+				r = (r + 1) & CMX_BUFF_MASK;
+			}
+			while (r != rr) {
+				*d++ = q[r]; /* echo */
+				r = (r + 1) & CMX_BUFF_MASK;
+			}
+		}
+		dsp->tx_R = t;
+		goto send_packet;
+	}
+	/* PROCESS DATA (two members) */
+#ifdef CMX_CONF_DEBUG
+	if (0) {
+#else
+	if (members == 2) {
+#endif
+		/* "other" becomes other party */
+		other = (list_entry(conf->mlist.next,
+				    struct dsp_conf_member, list))->dsp;
+		if (other == member)
+			other = (list_entry(conf->mlist.prev,
+				    struct dsp_conf_member, list))->dsp;
+		o_q = other->rx_buff; /* received data */
+		o_rr = (other->rx_R + len) & CMX_BUFF_MASK;
+		/* end of rx-pointer */
+		o_r = (o_rr - rr + r) & CMX_BUFF_MASK;
+		/* start rx-pointer at current read position*/
+		/* -> if echo is NOT enabled */
+		if (!dsp->echo.software) {
+			/*
+			 * -> copy other member's rx-data,
+			 * if tx-data is available, mix
+			 */
+			while (o_r != o_rr && t != tt) {
+				*d++ = dsp_audio_mix_law[(p[t] << 8) | o_q[o_r]];
+				t = (t + 1) & CMX_BUFF_MASK;
+				o_r = (o_r + 1) & CMX_BUFF_MASK;
+			}
+			while (o_r != o_rr) {
+				*d++ = o_q[o_r];
+				o_r = (o_r + 1) & CMX_BUFF_MASK;
+			}
+			/* -> if echo is enabled */
+		} else {
+			/*
+			 * -> mix other member's rx-data with echo,
+			 * if tx-data is available, mix
+			 */
+			while (r != rr && t != tt) {
+				sample = dsp_audio_law_to_s32[p[t]] +
+					dsp_audio_law_to_s32[q[r]] +
+					dsp_audio_law_to_s32[o_q[o_r]];
+				if (sample < -32768)
+					sample = -32768;
+				else if (sample > 32767)
+					sample = 32767;
+				*d++ = dsp_audio_s16_to_law[sample & 0xffff];
+				/* tx-data + rx_data + echo */
+				t = (t + 1) & CMX_BUFF_MASK;
+				r = (r + 1) & CMX_BUFF_MASK;
+				o_r = (o_r + 1) & CMX_BUFF_MASK;
+			}
+			while (r != rr) {
+				*d++ = dsp_audio_mix_law[(q[r] << 8) | o_q[o_r]];
+				r = (r + 1) & CMX_BUFF_MASK;
+				o_r = (o_r + 1) & CMX_BUFF_MASK;
+			}
+		}
+		dsp->tx_R = t;
+		goto send_packet;
+	}
+	/* PROCESS DATA (three or more members) */
+	/* -> if echo is NOT enabled */
+	if (!dsp->echo.software) {
+		/*
+		 * -> subtract rx-data from conf-data,
+		 * if tx-data is available, mix
+		 */
+		while (r != rr && t != tt) {
+			sample = dsp_audio_law_to_s32[p[t]] + *c++ -
+				dsp_audio_law_to_s32[q[r]];
+			if (sample < -32768)
+				sample = -32768;
+			else if (sample > 32767)
+				sample = 32767;
+			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
+			/* conf-rx+tx */
+			r = (r + 1) & CMX_BUFF_MASK;
+			t = (t + 1) & CMX_BUFF_MASK;
+		}
+		while (r != rr) {
+			sample = *c++ - dsp_audio_law_to_s32[q[r]];
+			if (sample < -32768)
+				sample = -32768;
+			else if (sample > 32767)
+				sample = 32767;
+			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
+			/* conf-rx */
+			r = (r + 1) & CMX_BUFF_MASK;
+		}
+		/* -> if echo is enabled */
+	} else {
+		/*
+		 * -> encode conf-data, if tx-data
+		 * is available, mix
+		 */
+		while (r != rr && t != tt) {
+			sample = dsp_audio_law_to_s32[p[t]] + *c++;
+			if (sample < -32768)
+				sample = -32768;
+			else if (sample > 32767)
+				sample = 32767;
+			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
+			/* conf(echo)+tx */
+			t = (t + 1) & CMX_BUFF_MASK;
+			r = (r + 1) & CMX_BUFF_MASK;
+		}
+		while (r != rr) {
+			sample = *c++;
+			if (sample < -32768)
+				sample = -32768;
+			else if (sample > 32767)
+				sample = 32767;
+			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
+			/* conf(echo) */
+			r = (r + 1) & CMX_BUFF_MASK;
+		}
+	}
+	dsp->tx_R = t;
+	goto send_packet;
+
+send_packet:
+	/*
+	 * send tx-data if enabled - don't filter,
+	 * because we want what we send, not what we filtered
+	 */
+	if (dsp->tx_data) {
+		if (tx_data_only) {
+			hh->prim = DL_DATA_REQ;
+			hh->id = 0;
+			/* queue and trigger */
+			skb_queue_tail(&dsp->sendq, nskb);
+			schedule_work(&dsp->workq);
+			/* exit because only tx_data is used */
+			return;
+		} else {
+			txskb = mI_alloc_skb(len, GFP_ATOMIC);
+			if (!txskb) {
+				printk(KERN_ERR
+				       "FATAL ERROR in mISDN_dsp.o: "
+				       "cannot alloc %d bytes\n", len);
+			} else {
+				thh = mISDN_HEAD_P(txskb);
+				thh->prim = DL_DATA_REQ;
+				thh->id = 0;
+				skb_put_data(txskb, nskb->data + preload, len);
+				/* queue (trigger later) */
+				skb_queue_tail(&dsp->sendq, txskb);
+			}
+		}
+	}
+
+	/* send data only to card, if we don't just calculated tx_data */
+	/* adjust volume */
+	if (dsp->tx_volume)
+		dsp_change_volume(nskb, dsp->tx_volume);
+	/* pipeline */
+	if (dsp->pipeline.inuse)
+		dsp_pipeline_process_tx(&dsp->pipeline, nskb->data,
+					nskb->len);
+	/* crypt */
+	if (dsp->bf_enable)
+		dsp_bf_encrypt(dsp, nskb->data, nskb->len);
+	/* queue and trigger */
+	skb_queue_tail(&dsp->sendq, nskb);
+	schedule_work(&dsp->workq);
+}
+
+static u32	jittercount; /* counter for jitter check */
+struct timer_list dsp_spl_tl;
+unsigned long	dsp_spl_jiffies; /* calculate the next time to fire */
+static u16	dsp_count; /* last sample count */
+static int	dsp_count_valid; /* if we have last sample count */
+
+void
+dsp_cmx_send(struct timer_list *arg)
+{
+	struct dsp_conf *conf;
+	struct dsp_conf_member *member;
+	struct dsp *dsp;
+	int mustmix, members;
+	static s32 mixbuffer[MAX_POLL + 100];
+	s32 *c;
+	u8 *p, *q;
+	int r, rr;
+	int jittercheck = 0, delay, i;
+	u_long flags;
+	u16 length, count;
+
+	/* lock */
+	spin_lock_irqsave(&dsp_lock, flags);
+
+	if (!dsp_count_valid) {
+		dsp_count = mISDN_clock_get();
+		length = dsp_poll;
+		dsp_count_valid = 1;
+	} else {
+		count = mISDN_clock_get();
+		length = count - dsp_count;
+		dsp_count = count;
+	}
+	if (length > MAX_POLL + 100)
+		length = MAX_POLL + 100;
+	/* printk(KERN_DEBUG "len=%d dsp_count=0x%x\n", length, dsp_count); */
+
+	/*
+	 * check if jitter needs to be checked (this is every second)
+	 */
+	jittercount += length;
+	if (jittercount >= 8000) {
+		jittercount -= 8000;
+		jittercheck = 1;
+	}
+
+	/* loop all members that do not require conference mixing */
+	list_for_each_entry(dsp, &dsp_ilist, list) {
+		if (dsp->hdlc)
+			continue;
+		conf = dsp->conf;
+		mustmix = 0;
+		members = 0;
+		if (conf) {
+			members = count_list_member(&conf->mlist);
+#ifdef CMX_CONF_DEBUG
+			if (conf->software && members > 1)
+#else
+			if (conf->software && members > 2)
+#endif
+				mustmix = 1;
+		}
+
+		/* transmission required */
+		if (!mustmix) {
+			dsp_cmx_send_member(dsp, length, mixbuffer, members);
+
+			/*
+			 * unused mixbuffer is given to prevent a
+			 * potential null-pointer-bug
+			 */
+		}
+	}
+
+	/* loop all members that require conference mixing */
+	list_for_each_entry(conf, &conf_ilist, list) {
+		/* count members and check hardware */
+		members = count_list_member(&conf->mlist);
+#ifdef CMX_CONF_DEBUG
+		if (conf->software && members > 1) {
+#else
+		if (conf->software && members > 2) {
+#endif
+			/* check for hdlc conf */
+			member = list_entry(conf->mlist.next,
+					    struct dsp_conf_member, list);
+			if (member->dsp->hdlc)
+				continue;
+			/* mix all data */
+			memset(mixbuffer, 0, length * sizeof(s32));
+			list_for_each_entry(member, &conf->mlist, list) {
+				dsp = member->dsp;
+				/* get range of data to mix */
+				c = mixbuffer;
+				q = dsp->rx_buff;
+				r = dsp->rx_R;
+				rr = (r + length) & CMX_BUFF_MASK;
+				/* add member's data */
+				while (r != rr) {
+					*c++ += dsp_audio_law_to_s32[q[r]];
+					r = (r + 1) & CMX_BUFF_MASK;
+				}
+			}
+
+			/* process each member */
+			list_for_each_entry(member, &conf->mlist, list) {
+				/* transmission */
+				dsp_cmx_send_member(member->dsp, length,
+						    mixbuffer, members);
+			}
+		}
+	}
+
+	/* delete rx-data, increment buffers, change pointers */
+	list_for_each_entry(dsp, &dsp_ilist, list) {
+		if (dsp->hdlc)
+			continue;
+		p = dsp->rx_buff;
+		q = dsp->tx_buff;
+		r = dsp->rx_R;
+		/* move receive pointer when receiving */
+		if (!dsp->rx_is_off) {
+			rr = (r + length) & CMX_BUFF_MASK;
+			/* delete rx-data */
+			while (r != rr) {
+				p[r] = dsp_silence;
+				r = (r + 1) & CMX_BUFF_MASK;
+			}
+			/* increment rx-buffer pointer */
+			dsp->rx_R = r; /* write incremented read pointer */
+		}
+
+		/* check current rx_delay */
+		delay = (dsp->rx_W-dsp->rx_R) & CMX_BUFF_MASK;
+		if (delay >= CMX_BUFF_HALF)
+			delay = 0; /* will be the delay before next write */
+		/* check for lower delay */
+		if (delay < dsp->rx_delay[0])
+			dsp->rx_delay[0] = delay;
+		/* check current tx_delay */
+		delay = (dsp->tx_W-dsp->tx_R) & CMX_BUFF_MASK;
+		if (delay >= CMX_BUFF_HALF)
+			delay = 0; /* will be the delay before next write */
+		/* check for lower delay */
+		if (delay < dsp->tx_delay[0])
+			dsp->tx_delay[0] = delay;
+		if (jittercheck) {
+			/* find the lowest of all rx_delays */
+			delay = dsp->rx_delay[0];
+			i = 1;
+			while (i < MAX_SECONDS_JITTER_CHECK) {
+				if (delay > dsp->rx_delay[i])
+					delay = dsp->rx_delay[i];
+				i++;
+			}
+			/*
+			 * remove rx_delay only if we have delay AND we
+			 * have not preset cmx_delay AND
+			 * the delay is greater dsp_poll
+			 */
+			if (delay > dsp_poll && !dsp->cmx_delay) {
+				if (dsp_debug & DEBUG_DSP_CLOCK)
+					printk(KERN_DEBUG
+					       "%s lowest rx_delay of %d bytes for"
+					       " dsp %s are now removed.\n",
+					       __func__, delay,
+					       dsp->name);
+				r = dsp->rx_R;
+				rr = (r + delay - (dsp_poll >> 1))
+					& CMX_BUFF_MASK;
+				/* delete rx-data */
+				while (r != rr) {
+					p[r] = dsp_silence;
+					r = (r + 1) & CMX_BUFF_MASK;
+				}
+				/* increment rx-buffer pointer */
+				dsp->rx_R = r;
+				/* write incremented read pointer */
+			}
+			/* find the lowest of all tx_delays */
+			delay = dsp->tx_delay[0];
+			i = 1;
+			while (i < MAX_SECONDS_JITTER_CHECK) {
+				if (delay > dsp->tx_delay[i])
+					delay = dsp->tx_delay[i];
+				i++;
+			}
+			/*
+			 * remove delay only if we have delay AND we
+			 * have enabled tx_dejitter
+			 */
+			if (delay > dsp_poll && dsp->tx_dejitter) {
+				if (dsp_debug & DEBUG_DSP_CLOCK)
+					printk(KERN_DEBUG
+					       "%s lowest tx_delay of %d bytes for"
+					       " dsp %s are now removed.\n",
+					       __func__, delay,
+					       dsp->name);
+				r = dsp->tx_R;
+				rr = (r + delay - (dsp_poll >> 1))
+					& CMX_BUFF_MASK;
+				/* delete tx-data */
+				while (r != rr) {
+					q[r] = dsp_silence;
+					r = (r + 1) & CMX_BUFF_MASK;
+				}
+				/* increment rx-buffer pointer */
+				dsp->tx_R = r;
+				/* write incremented read pointer */
+			}
+			/* scroll up delays */
+			i = MAX_SECONDS_JITTER_CHECK - 1;
+			while (i) {
+				dsp->rx_delay[i] = dsp->rx_delay[i - 1];
+				dsp->tx_delay[i] = dsp->tx_delay[i - 1];
+				i--;
+			}
+			dsp->tx_delay[0] = CMX_BUFF_HALF; /* (infinite) delay */
+			dsp->rx_delay[0] = CMX_BUFF_HALF; /* (infinite) delay */
+		}
+	}
+
+	/* if next event would be in the past ... */
+	if ((s32)(dsp_spl_jiffies + dsp_tics-jiffies) <= 0)
+		dsp_spl_jiffies = jiffies + 1;
+	else
+		dsp_spl_jiffies += dsp_tics;
+
+	dsp_spl_tl.expires = dsp_spl_jiffies;
+	add_timer(&dsp_spl_tl);
+
+	/* unlock */
+	spin_unlock_irqrestore(&dsp_lock, flags);
+}
+
+/*
+ * audio data is transmitted from upper layer to the dsp
+ */
+void
+dsp_cmx_transmit(struct dsp *dsp, struct sk_buff *skb)
+{
+	u_int w, ww;
+	u8 *d, *p;
+	int space; /* todo: , l = skb->len; */
+#ifdef CMX_TX_DEBUG
+	char debugbuf[256] = "";
+#endif
+
+	/* check if there is enough space, and then copy */
+	w = dsp->tx_W;
+	ww = dsp->tx_R;
+	p = dsp->tx_buff;
+	d = skb->data;
+	space = (ww - w - 1) & CMX_BUFF_MASK;
+	/* write-pointer should not overrun nor reach read pointer */
+	if (space < skb->len) {
+		/* write to the space we have left */
+		ww = (ww - 1) & CMX_BUFF_MASK; /* end one byte prior tx_R */
+		if (dsp_debug & DEBUG_DSP_CLOCK)
+			printk(KERN_DEBUG "%s: TX overflow space=%d skb->len="
+			       "%d, w=0x%04x, ww=0x%04x\n", __func__, space,
+			       skb->len, w, ww);
+	} else
+		/* write until all byte are copied */
+		ww = (w + skb->len) & CMX_BUFF_MASK;
+	dsp->tx_W = ww;
+		/* show current buffer */
+#ifdef CMX_DEBUG
+	printk(KERN_DEBUG
+	       "cmx_transmit(dsp=%lx) %d bytes to 0x%x-0x%x. %s\n",
+	       (u_long)dsp, (ww - w) & CMX_BUFF_MASK, w, ww, dsp->name);
+#endif
+
+	/* copy transmit data to tx-buffer */
+#ifdef CMX_TX_DEBUG
+	sprintf(debugbuf, "TX getting (%04x-%04x)%p: ", w, ww, p);
+#endif
+	while (w != ww) {
+#ifdef CMX_TX_DEBUG
+		if (strlen(debugbuf) < 48)
+			sprintf(debugbuf + strlen(debugbuf), " %02x", *d);
+#endif
+		p[w] = *d++;
+		w = (w + 1) & CMX_BUFF_MASK;
+	}
+#ifdef CMX_TX_DEBUG
+	printk(KERN_DEBUG "%s\n", debugbuf);
+#endif
+
+}
+
+/*
+ * hdlc data is received from card and sent to all members.
+ */
+void
+dsp_cmx_hdlc(struct dsp *dsp, struct sk_buff *skb)
+{
+	struct sk_buff *nskb = NULL;
+	struct dsp_conf_member *member;
+	struct mISDNhead *hh;
+
+	/* not if not active */
+	if (!dsp->b_active)
+		return;
+
+	/* check if we have sompen */
+	if (skb->len < 1)
+		return;
+
+	/* no conf */
+	if (!dsp->conf) {
+		/* in case of software echo */
+		if (dsp->echo.software) {
+			nskb = skb_clone(skb, GFP_ATOMIC);
+			if (nskb) {
+				hh = mISDN_HEAD_P(nskb);
+				hh->prim = PH_DATA_REQ;
+				hh->id = 0;
+				skb_queue_tail(&dsp->sendq, nskb);
+				schedule_work(&dsp->workq);
+			}
+		}
+		return;
+	}
+	/* in case of hardware conference */
+	if (dsp->conf->hardware)
+		return;
+	list_for_each_entry(member, &dsp->conf->mlist, list) {
+		if (dsp->echo.software || member->dsp != dsp) {
+			nskb = skb_clone(skb, GFP_ATOMIC);
+			if (nskb) {
+				hh = mISDN_HEAD_P(nskb);
+				hh->prim = PH_DATA_REQ;
+				hh->id = 0;
+				skb_queue_tail(&member->dsp->sendq, nskb);
+				schedule_work(&member->dsp->workq);
+			}
+		}
+	}
+}
diff --git a/drivers/isdn/mISDN/dsp_core.c b/drivers/isdn/mISDN/dsp_core.c
new file mode 100644
index 000000000..fae95f166
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_core.c
@@ -0,0 +1,1226 @@
+/*
+ * Author       Andreas Eversberg (jolly@eversberg.eu)
+ * Based on source code structure by
+ *		Karsten Keil (keil@isdn4linux.de)
+ *
+ *		This file is (c) under GNU PUBLIC LICENSE
+ *
+ * Thanks to    Karsten Keil (great drivers)
+ *              Cologne Chip (great chips)
+ *
+ * This module does:
+ *		Real-time tone generation
+ *		DTMF detection
+ *		Real-time cross-connection and conferrence
+ *		Compensate jitter due to system load and hardware fault.
+ *		All features are done in kernel space and will be realized
+ *		using hardware, if available and supported by chip set.
+ *		Blowfish encryption/decryption
+ */
+
+/* STRUCTURE:
+ *
+ * The dsp module provides layer 2 for b-channels (64kbit). It provides
+ * transparent audio forwarding with special digital signal processing:
+ *
+ * - (1) generation of tones
+ * - (2) detection of dtmf tones
+ * - (3) crossconnecting and conferences (clocking)
+ * - (4) echo generation for delay test
+ * - (5) volume control
+ * - (6) disable receive data
+ * - (7) pipeline
+ * - (8) encryption/decryption
+ *
+ * Look:
+ *             TX            RX
+ *         ------upper layer------
+ *             |             ^
+ *             |             |(6)
+ *             v             |
+ *       +-----+-------------+-----+
+ *       |(3)(4)                   |
+ *       |           CMX           |
+ *       |                         |
+ *       |           +-------------+
+ *       |           |       ^
+ *       |           |       |
+ *       |+---------+|  +----+----+
+ *       ||(1)      ||  |(2)      |
+ *       ||         ||  |         |
+ *       ||  Tones  ||  |  DTMF   |
+ *       ||         ||  |         |
+ *       ||         ||  |         |
+ *       |+----+----+|  +----+----+
+ *       +-----+-----+       ^
+ *             |             |
+ *             v             |
+ *        +----+----+   +----+----+
+ *        |(5)      |   |(5)      |
+ *        |         |   |         |
+ *        |TX Volume|   |RX Volume|
+ *        |         |   |         |
+ *        |         |   |         |
+ *        +----+----+   +----+----+
+ *             |             ^
+ *             |             |
+ *             v             |
+ *        +----+-------------+----+
+ *        |(7)                    |
+ *        |                       |
+ *        |  Pipeline Processing  |
+ *        |                       |
+ *        |                       |
+ *        +----+-------------+----+
+ *             |             ^
+ *             |             |
+ *             v             |
+ *        +----+----+   +----+----+
+ *        |(8)      |   |(8)      |
+ *        |         |   |         |
+ *        | Encrypt |   | Decrypt |
+ *        |         |   |         |
+ *        |         |   |         |
+ *        +----+----+   +----+----+
+ *             |             ^
+ *             |             |
+ *             v             |
+ *         ------card  layer------
+ *             TX            RX
+ *
+ * Above you can see the logical data flow. If software is used to do the
+ * process, it is actually the real data flow. If hardware is used, data
+ * may not flow, but hardware commands to the card, to provide the data flow
+ * as shown.
+ *
+ * NOTE: The channel must be activated in order to make dsp work, even if
+ * no data flow to the upper layer is intended. Activation can be done
+ * after and before controlling the setting using PH_CONTROL requests.
+ *
+ * DTMF: Will be detected by hardware if possible. It is done before CMX
+ * processing.
+ *
+ * Tones: Will be generated via software if endless looped audio fifos are
+ * not supported by hardware. Tones will override all data from CMX.
+ * It is not required to join a conference to use tones at any time.
+ *
+ * CMX: Is transparent when not used. When it is used, it will do
+ * crossconnections and conferences via software if not possible through
+ * hardware. If hardware capability is available, hardware is used.
+ *
+ * Echo: Is generated by CMX and is used to check performance of hard and
+ * software CMX.
+ *
+ * The CMX has special functions for conferences with one, two and more
+ * members. It will allow different types of data flow. Receive and transmit
+ * data to/form upper layer may be switched on/off individually without losing
+ * features of CMX, Tones and DTMF.
+ *
+ * Echo Cancellation: Sometimes we like to cancel echo from the interface.
+ * Note that a VoIP call may not have echo caused by the IP phone. The echo
+ * is generated by the telephone line connected to it. Because the delay
+ * is high, it becomes an echo. RESULT: Echo Cachelation is required if
+ * both echo AND delay is applied to an interface.
+ * Remember that software CMX always generates a more or less delay.
+ *
+ * If all used features can be realized in hardware, and if transmit and/or
+ * receive data ist disabled, the card may not send/receive any data at all.
+ * Not receiving is useful if only announcements are played. Not sending is
+ * useful if an answering machine records audio. Not sending and receiving is
+ * useful during most states of the call. If supported by hardware, tones
+ * will be played without cpu load. Small PBXs and NT-Mode applications will
+ * not need expensive hardware when processing calls.
+ *
+ *
+ * LOCKING:
+ *
+ * When data is received from upper or lower layer (card), the complete dsp
+ * module is locked by a global lock.  This lock MUST lock irq, because it
+ * must lock timer events by DSP poll timer.
+ * When data is ready to be transmitted down, the data is queued and sent
+ * outside lock and timer event.
+ * PH_CONTROL must not change any settings, join or split conference members
+ * during process of data.
+ *
+ * HDLC:
+ *
+ * It works quite the same as transparent, except that HDLC data is forwarded
+ * to all other conference members if no hardware bridging is possible.
+ * Send data will be writte to sendq. Sendq will be sent if confirm is received.
+ * Conference cannot join, if one member is not hdlc.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/gfp.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include "core.h"
+#include "dsp.h"
+
+static const char *mISDN_dsp_revision = "2.0";
+
+static int debug;
+static int options;
+static int poll;
+static int dtmfthreshold = 100;
+
+MODULE_AUTHOR("Andreas Eversberg");
+module_param(debug, uint, S_IRUGO | S_IWUSR);
+module_param(options, uint, S_IRUGO | S_IWUSR);
+module_param(poll, uint, S_IRUGO | S_IWUSR);
+module_param(dtmfthreshold, uint, S_IRUGO | S_IWUSR);
+MODULE_LICENSE("GPL");
+
+/*int spinnest = 0;*/
+
+DEFINE_SPINLOCK(dsp_lock); /* global dsp lock */
+LIST_HEAD(dsp_ilist);
+LIST_HEAD(conf_ilist);
+int dsp_debug;
+int dsp_options;
+int dsp_poll, dsp_tics;
+
+/* check if rx may be turned off or must be turned on */
+static void
+dsp_rx_off_member(struct dsp *dsp)
+{
+	struct mISDN_ctrl_req	cq;
+	int rx_off = 1;
+
+	memset(&cq, 0, sizeof(cq));
+
+	if (!dsp->features_rx_off)
+		return;
+
+	/* not disabled */
+	if (!dsp->rx_disabled)
+		rx_off = 0;
+	/* software dtmf */
+	else if (dsp->dtmf.software)
+		rx_off = 0;
+	/* echo in software */
+	else if (dsp->echo.software)
+		rx_off = 0;
+	/* bridge in software */
+	else if (dsp->conf && dsp->conf->software)
+		rx_off = 0;
+	/* data is not required by user space and not required
+	 * for echo dtmf detection, soft-echo, soft-bridging */
+
+	if (rx_off == dsp->rx_is_off)
+		return;
+
+	if (!dsp->ch.peer) {
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: no peer, no rx_off\n",
+			       __func__);
+		return;
+	}
+	cq.op = MISDN_CTRL_RX_OFF;
+	cq.p1 = rx_off;
+	if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
+		printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
+		       __func__);
+		return;
+	}
+	dsp->rx_is_off = rx_off;
+	if (dsp_debug & DEBUG_DSP_CORE)
+		printk(KERN_DEBUG "%s: %s set rx_off = %d\n",
+		       __func__, dsp->name, rx_off);
+}
+static void
+dsp_rx_off(struct dsp *dsp)
+{
+	struct dsp_conf_member	*member;
+
+	if (dsp_options & DSP_OPT_NOHARDWARE)
+		return;
+
+	/* no conf */
+	if (!dsp->conf) {
+		dsp_rx_off_member(dsp);
+		return;
+	}
+	/* check all members in conf */
+	list_for_each_entry(member, &dsp->conf->mlist, list) {
+		dsp_rx_off_member(member->dsp);
+	}
+}
+
+/* enable "fill empty" feature */
+static void
+dsp_fill_empty(struct dsp *dsp)
+{
+	struct mISDN_ctrl_req	cq;
+
+	memset(&cq, 0, sizeof(cq));
+
+	if (!dsp->ch.peer) {
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: no peer, no fill_empty\n",
+			       __func__);
+		return;
+	}
+	cq.op = MISDN_CTRL_FILL_EMPTY;
+	cq.p1 = 1;
+	cq.p2 = dsp_silence;
+	if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
+		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
+		       __func__);
+		return;
+	}
+	if (dsp_debug & DEBUG_DSP_CORE)
+		printk(KERN_DEBUG "%s: %s set fill_empty = 1\n",
+		       __func__, dsp->name);
+}
+
+static int
+dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
+{
+	struct sk_buff	*nskb;
+	int ret = 0;
+	int cont;
+	u8 *data;
+	int len;
+
+	if (skb->len < sizeof(int)) {
+		printk(KERN_ERR "%s: PH_CONTROL message too short\n", __func__);
+		return -EINVAL;
+	}
+	cont = *((int *)skb->data);
+	len = skb->len - sizeof(int);
+	data = skb->data + sizeof(int);
+
+	switch (cont) {
+	case DTMF_TONE_START: /* turn on DTMF */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: start dtmf\n", __func__);
+		if (len == sizeof(int)) {
+			if (dsp_debug & DEBUG_DSP_CORE)
+				printk(KERN_NOTICE "changing DTMF Threshold "
+				       "to %d\n", *((int *)data));
+			dsp->dtmf.treshold = (*(int *)data) * 10000;
+		}
+		dsp->dtmf.enable = 1;
+		/* init goertzel */
+		dsp_dtmf_goertzel_init(dsp);
+
+		/* check dtmf hardware */
+		dsp_dtmf_hardware(dsp);
+		dsp_rx_off(dsp);
+		break;
+	case DTMF_TONE_STOP: /* turn off DTMF */
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
+		dsp->dtmf.enable = 0;
+		dsp->dtmf.hardware = 0;
+		dsp->dtmf.software = 0;
+		break;
+	case DSP_CONF_JOIN: /* join / update conference */
+		if (len < sizeof(int)) {
+			ret = -EINVAL;
+			break;
+		}
+		if (*((u32 *)data) == 0)
+			goto conf_split;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: join conference %d\n",
+			       __func__, *((u32 *)data));
+		ret = dsp_cmx_conf(dsp, *((u32 *)data));
+		/* dsp_cmx_hardware will also be called here */
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_CONF_SPLIT: /* remove from conference */
+	conf_split:
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: release conference\n", __func__);
+		ret = dsp_cmx_conf(dsp, 0);
+		/* dsp_cmx_hardware will also be called here */
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		dsp_rx_off(dsp);
+		break;
+	case DSP_TONE_PATT_ON: /* play tone */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len < sizeof(int)) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: turn tone 0x%x on\n",
+			       __func__, *((int *)skb->data));
+		ret = dsp_tone(dsp, *((int *)data));
+		if (!ret) {
+			dsp_cmx_hardware(dsp->conf, dsp);
+			dsp_rx_off(dsp);
+		}
+		if (!dsp->tone.tone)
+			goto tone_off;
+		break;
+	case DSP_TONE_PATT_OFF: /* stop tone */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: turn tone off\n", __func__);
+		dsp_tone(dsp, 0);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		/* reset tx buffers (user space data) */
+	tone_off:
+		dsp->rx_W = 0;
+		dsp->rx_R = 0;
+		break;
+	case DSP_VOL_CHANGE_TX: /* change volume */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len < sizeof(int)) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->tx_volume = *((int *)data);
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: change tx vol to %d\n",
+			       __func__, dsp->tx_volume);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_dtmf_hardware(dsp);
+		dsp_rx_off(dsp);
+		break;
+	case DSP_VOL_CHANGE_RX: /* change volume */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len < sizeof(int)) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->rx_volume = *((int *)data);
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: change rx vol to %d\n",
+			       __func__, dsp->tx_volume);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_dtmf_hardware(dsp);
+		dsp_rx_off(dsp);
+		break;
+	case DSP_ECHO_ON: /* enable echo */
+		dsp->echo.software = 1; /* soft echo */
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: enable cmx-echo\n", __func__);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_ECHO_OFF: /* disable echo */
+		dsp->echo.software = 0;
+		dsp->echo.hardware = 0;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: disable cmx-echo\n", __func__);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_RECEIVE_ON: /* enable receive to user space */
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: enable receive to user "
+			       "space\n", __func__);
+		dsp->rx_disabled = 0;
+		dsp_rx_off(dsp);
+		break;
+	case DSP_RECEIVE_OFF: /* disable receive to user space */
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: disable receive to "
+			       "user space\n", __func__);
+		dsp->rx_disabled = 1;
+		dsp_rx_off(dsp);
+		break;
+	case DSP_MIX_ON: /* enable mixing of tx data */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: enable mixing of "
+			       "tx-data with conf members\n", __func__);
+		dsp->tx_mix = 1;
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_MIX_OFF: /* disable mixing of tx data */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: disable mixing of "
+			       "tx-data with conf members\n", __func__);
+		dsp->tx_mix = 0;
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_TXDATA_ON: /* enable txdata */
+		dsp->tx_data = 1;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: enable tx-data\n", __func__);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_TXDATA_OFF: /* disable txdata */
+		dsp->tx_data = 0;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: disable tx-data\n", __func__);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		if (dsp_debug & DEBUG_DSP_CMX)
+			dsp_cmx_debug(dsp);
+		break;
+	case DSP_DELAY: /* use delay algorithm instead of dynamic
+			   jitter algorithm */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len < sizeof(int)) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->cmx_delay = (*((int *)data)) << 3;
+		/* milliseconds to samples */
+		if (dsp->cmx_delay >= (CMX_BUFF_HALF >> 1))
+			/* clip to half of maximum usable buffer
+			   (half of half buffer) */
+			dsp->cmx_delay = (CMX_BUFF_HALF >> 1) - 1;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: use delay algorithm to "
+			       "compensate jitter (%d samples)\n",
+			       __func__, dsp->cmx_delay);
+		break;
+	case DSP_JITTER: /* use dynamic jitter algorithm instead of
+			    delay algorithm */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->cmx_delay = 0;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: use jitter algorithm to "
+			       "compensate jitter\n", __func__);
+		break;
+	case DSP_TX_DEJITTER: /* use dynamic jitter algorithm for tx-buffer */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->tx_dejitter = 1;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: use dejitter on TX "
+			       "buffer\n", __func__);
+		break;
+	case DSP_TX_DEJ_OFF: /* use tx-buffer without dejittering*/
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		dsp->tx_dejitter = 0;
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: use TX buffer without "
+			       "dejittering\n", __func__);
+		break;
+	case DSP_PIPELINE_CFG:
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len > 0 && ((char *)data)[len - 1]) {
+			printk(KERN_DEBUG "%s: pipeline config string "
+			       "is not NULL terminated!\n", __func__);
+			ret = -EINVAL;
+		} else {
+			dsp->pipeline.inuse = 1;
+			dsp_cmx_hardware(dsp->conf, dsp);
+			ret = dsp_pipeline_build(&dsp->pipeline,
+						 len > 0 ? data : NULL);
+			dsp_cmx_hardware(dsp->conf, dsp);
+			dsp_rx_off(dsp);
+		}
+		break;
+	case DSP_BF_ENABLE_KEY: /* turn blowfish on */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (len < 4 || len > 56) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: turn blowfish on (key "
+			       "not shown)\n", __func__);
+		ret = dsp_bf_init(dsp, (u8 *)data, len);
+		/* set new cont */
+		if (!ret)
+			cont = DSP_BF_ACCEPT;
+		else
+			cont = DSP_BF_REJECT;
+		/* send indication if it worked to set it */
+		nskb = _alloc_mISDN_skb(PH_CONTROL_IND, MISDN_ID_ANY,
+					sizeof(int), &cont, GFP_ATOMIC);
+		if (nskb) {
+			if (dsp->up) {
+				if (dsp->up->send(dsp->up, nskb))
+					dev_kfree_skb(nskb);
+			} else
+				dev_kfree_skb(nskb);
+		}
+		if (!ret) {
+			dsp_cmx_hardware(dsp->conf, dsp);
+			dsp_dtmf_hardware(dsp);
+			dsp_rx_off(dsp);
+		}
+		break;
+	case DSP_BF_DISABLE: /* turn blowfish off */
+		if (dsp->hdlc) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: turn blowfish off\n", __func__);
+		dsp_bf_cleanup(dsp);
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_dtmf_hardware(dsp);
+		dsp_rx_off(dsp);
+		break;
+	default:
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: ctrl req %x unhandled\n",
+			       __func__, cont);
+		ret = -EINVAL;
+	}
+	return ret;
+}
+
+static void
+get_features(struct mISDNchannel *ch)
+{
+	struct dsp		*dsp = container_of(ch, struct dsp, ch);
+	struct mISDN_ctrl_req	cq;
+
+	if (!ch->peer) {
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: no peer, no features\n",
+			       __func__);
+		return;
+	}
+	memset(&cq, 0, sizeof(cq));
+	cq.op = MISDN_CTRL_GETOP;
+	if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq) < 0) {
+		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
+		       __func__);
+		return;
+	}
+	if (cq.op & MISDN_CTRL_RX_OFF)
+		dsp->features_rx_off = 1;
+	if (cq.op & MISDN_CTRL_FILL_EMPTY)
+		dsp->features_fill_empty = 1;
+	if (dsp_options & DSP_OPT_NOHARDWARE)
+		return;
+	if ((cq.op & MISDN_CTRL_HW_FEATURES_OP)) {
+		cq.op = MISDN_CTRL_HW_FEATURES;
+		*((u_long *)&cq.p1) = (u_long)&dsp->features;
+		if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq)) {
+			printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
+			       __func__);
+		}
+	} else
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: features not supported for %s\n",
+			       __func__, dsp->name);
+}
+
+static int
+dsp_function(struct mISDNchannel *ch,  struct sk_buff *skb)
+{
+	struct dsp		*dsp = container_of(ch, struct dsp, ch);
+	struct mISDNhead	*hh;
+	int			ret = 0;
+	u8			*digits = NULL;
+	u_long			flags;
+
+	hh = mISDN_HEAD_P(skb);
+	switch (hh->prim) {
+		/* FROM DOWN */
+	case (PH_DATA_CNF):
+		dsp->data_pending = 0;
+		/* trigger next hdlc frame, if any */
+		if (dsp->hdlc) {
+			spin_lock_irqsave(&dsp_lock, flags);
+			if (dsp->b_active)
+				schedule_work(&dsp->workq);
+			spin_unlock_irqrestore(&dsp_lock, flags);
+		}
+		break;
+	case (PH_DATA_IND):
+	case (DL_DATA_IND):
+		if (skb->len < 1) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp->rx_is_off) {
+			if (dsp_debug & DEBUG_DSP_CORE)
+				printk(KERN_DEBUG "%s: rx-data during rx_off"
+				       " for %s\n",
+				       __func__, dsp->name);
+		}
+		if (dsp->hdlc) {
+			/* hdlc */
+			spin_lock_irqsave(&dsp_lock, flags);
+			dsp_cmx_hdlc(dsp, skb);
+			spin_unlock_irqrestore(&dsp_lock, flags);
+			if (dsp->rx_disabled) {
+				/* if receive is not allowed */
+				break;
+			}
+			hh->prim = DL_DATA_IND;
+			if (dsp->up)
+				return dsp->up->send(dsp->up, skb);
+			break;
+		}
+
+		spin_lock_irqsave(&dsp_lock, flags);
+
+		/* decrypt if enabled */
+		if (dsp->bf_enable)
+			dsp_bf_decrypt(dsp, skb->data, skb->len);
+		/* pipeline */
+		if (dsp->pipeline.inuse)
+			dsp_pipeline_process_rx(&dsp->pipeline, skb->data,
+						skb->len, hh->id);
+		/* change volume if requested */
+		if (dsp->rx_volume)
+			dsp_change_volume(skb, dsp->rx_volume);
+		/* check if dtmf soft decoding is turned on */
+		if (dsp->dtmf.software) {
+			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
+							  skb->len, (dsp_options & DSP_OPT_ULAW) ? 1 : 0);
+		}
+		/* we need to process receive data if software */
+		if (dsp->conf && dsp->conf->software) {
+			/* process data from card at cmx */
+			dsp_cmx_receive(dsp, skb);
+		}
+
+		spin_unlock_irqrestore(&dsp_lock, flags);
+
+		/* send dtmf result, if any */
+		if (digits) {
+			while (*digits) {
+				int k;
+				struct sk_buff *nskb;
+				if (dsp_debug & DEBUG_DSP_DTMF)
+					printk(KERN_DEBUG "%s: digit"
+					       "(%c) to layer %s\n",
+					       __func__, *digits, dsp->name);
+				k = *digits | DTMF_TONE_VAL;
+				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
+							MISDN_ID_ANY, sizeof(int), &k,
+							GFP_ATOMIC);
+				if (nskb) {
+					if (dsp->up) {
+						if (dsp->up->send(
+							    dsp->up, nskb))
+							dev_kfree_skb(nskb);
+					} else
+						dev_kfree_skb(nskb);
+				}
+				digits++;
+			}
+		}
+		if (dsp->rx_disabled) {
+			/* if receive is not allowed */
+			break;
+		}
+		hh->prim = DL_DATA_IND;
+		if (dsp->up)
+			return dsp->up->send(dsp->up, skb);
+		break;
+	case (PH_CONTROL_IND):
+		if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
+			printk(KERN_DEBUG "%s: PH_CONTROL INDICATION "
+			       "received: %x (len %d) %s\n", __func__,
+			       hh->id, skb->len, dsp->name);
+		switch (hh->id) {
+		case (DTMF_HFC_COEF): /* getting coefficients */
+			if (!dsp->dtmf.hardware) {
+				if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
+					printk(KERN_DEBUG "%s: ignoring DTMF "
+					       "coefficients from HFC\n",
+					       __func__);
+				break;
+			}
+			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
+							  skb->len, 2);
+			while (*digits) {
+				int k;
+				struct sk_buff *nskb;
+				if (dsp_debug & DEBUG_DSP_DTMF)
+					printk(KERN_DEBUG "%s: digit"
+					       "(%c) to layer %s\n",
+					       __func__, *digits, dsp->name);
+				k = *digits | DTMF_TONE_VAL;
+				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
+							MISDN_ID_ANY, sizeof(int), &k,
+							GFP_ATOMIC);
+				if (nskb) {
+					if (dsp->up) {
+						if (dsp->up->send(
+							    dsp->up, nskb))
+							dev_kfree_skb(nskb);
+					} else
+						dev_kfree_skb(nskb);
+				}
+				digits++;
+			}
+			break;
+		case (HFC_VOL_CHANGE_TX): /* change volume */
+			if (skb->len != sizeof(int)) {
+				ret = -EINVAL;
+				break;
+			}
+			spin_lock_irqsave(&dsp_lock, flags);
+			dsp->tx_volume = *((int *)skb->data);
+			if (dsp_debug & DEBUG_DSP_CORE)
+				printk(KERN_DEBUG "%s: change tx volume to "
+				       "%d\n", __func__, dsp->tx_volume);
+			dsp_cmx_hardware(dsp->conf, dsp);
+			dsp_dtmf_hardware(dsp);
+			dsp_rx_off(dsp);
+			spin_unlock_irqrestore(&dsp_lock, flags);
+			break;
+		default:
+			if (dsp_debug & DEBUG_DSP_CORE)
+				printk(KERN_DEBUG "%s: ctrl ind %x unhandled "
+				       "%s\n", __func__, hh->id, dsp->name);
+			ret = -EINVAL;
+		}
+		break;
+	case (PH_ACTIVATE_IND):
+	case (PH_ACTIVATE_CNF):
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: b_channel is now active %s\n",
+			       __func__, dsp->name);
+		/* bchannel now active */
+		spin_lock_irqsave(&dsp_lock, flags);
+		dsp->b_active = 1;
+		dsp->data_pending = 0;
+		dsp->rx_init = 1;
+		/* rx_W and rx_R will be adjusted on first frame */
+		dsp->rx_W = 0;
+		dsp->rx_R = 0;
+		memset(dsp->rx_buff, 0, sizeof(dsp->rx_buff));
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_dtmf_hardware(dsp);
+		dsp_rx_off(dsp);
+		spin_unlock_irqrestore(&dsp_lock, flags);
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: done with activation, sending "
+			       "confirm to user space. %s\n", __func__,
+			       dsp->name);
+		/* send activation to upper layer */
+		hh->prim = DL_ESTABLISH_CNF;
+		if (dsp->up)
+			return dsp->up->send(dsp->up, skb);
+		break;
+	case (PH_DEACTIVATE_IND):
+	case (PH_DEACTIVATE_CNF):
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: b_channel is now inactive %s\n",
+			       __func__, dsp->name);
+		/* bchannel now inactive */
+		spin_lock_irqsave(&dsp_lock, flags);
+		dsp->b_active = 0;
+		dsp->data_pending = 0;
+		dsp_cmx_hardware(dsp->conf, dsp);
+		dsp_rx_off(dsp);
+		spin_unlock_irqrestore(&dsp_lock, flags);
+		hh->prim = DL_RELEASE_CNF;
+		if (dsp->up)
+			return dsp->up->send(dsp->up, skb);
+		break;
+		/* FROM UP */
+	case (DL_DATA_REQ):
+	case (PH_DATA_REQ):
+		if (skb->len < 1) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dsp->hdlc) {
+			/* hdlc */
+			if (!dsp->b_active) {
+				ret = -EIO;
+				break;
+			}
+			hh->prim = PH_DATA_REQ;
+			spin_lock_irqsave(&dsp_lock, flags);
+			skb_queue_tail(&dsp->sendq, skb);
+			schedule_work(&dsp->workq);
+			spin_unlock_irqrestore(&dsp_lock, flags);
+			return 0;
+		}
+		/* send data to tx-buffer (if no tone is played) */
+		if (!dsp->tone.tone) {
+			spin_lock_irqsave(&dsp_lock, flags);
+			dsp_cmx_transmit(dsp, skb);
+			spin_unlock_irqrestore(&dsp_lock, flags);
+		}
+		break;
+	case (PH_CONTROL_REQ):
+		spin_lock_irqsave(&dsp_lock, flags);
+		ret = dsp_control_req(dsp, hh, skb);
+		spin_unlock_irqrestore(&dsp_lock, flags);
+		break;
+	case (DL_ESTABLISH_REQ):
+	case (PH_ACTIVATE_REQ):
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: activating b_channel %s\n",
+			       __func__, dsp->name);
+		if (dsp->dtmf.hardware || dsp->dtmf.software)
+			dsp_dtmf_goertzel_init(dsp);
+		get_features(ch);
+		/* enable fill_empty feature */
+		if (dsp->features_fill_empty)
+			dsp_fill_empty(dsp);
+		/* send ph_activate */
+		hh->prim = PH_ACTIVATE_REQ;
+		if (ch->peer)
+			return ch->recv(ch->peer, skb);
+		break;
+	case (DL_RELEASE_REQ):
+	case (PH_DEACTIVATE_REQ):
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: releasing b_channel %s\n",
+			       __func__, dsp->name);
+		spin_lock_irqsave(&dsp_lock, flags);
+		dsp->tone.tone = 0;
+		dsp->tone.hardware = 0;
+		dsp->tone.software = 0;
+		if (timer_pending(&dsp->tone.tl))
+			del_timer(&dsp->tone.tl);
+		if (dsp->conf)
+			dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be
+						 called here */
+		skb_queue_purge(&dsp->sendq);
+		spin_unlock_irqrestore(&dsp_lock, flags);
+		hh->prim = PH_DEACTIVATE_REQ;
+		if (ch->peer)
+			return ch->recv(ch->peer, skb);
+		break;
+	default:
+		if (dsp_debug & DEBUG_DSP_CORE)
+			printk(KERN_DEBUG "%s: msg %x unhandled %s\n",
+			       __func__, hh->prim, dsp->name);
+		ret = -EINVAL;
+	}
+	if (!ret)
+		dev_kfree_skb(skb);
+	return ret;
+}
+
+static int
+dsp_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct dsp		*dsp = container_of(ch, struct dsp, ch);
+	u_long		flags;
+
+	if (debug & DEBUG_DSP_CTRL)
+		printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
+
+	switch (cmd) {
+	case OPEN_CHANNEL:
+		break;
+	case CLOSE_CHANNEL:
+		if (dsp->ch.peer)
+			dsp->ch.peer->ctrl(dsp->ch.peer, CLOSE_CHANNEL, NULL);
+
+		/* wait until workqueue has finished,
+		 * must lock here, or we may hit send-process currently
+		 * queueing. */
+		spin_lock_irqsave(&dsp_lock, flags);
+		dsp->b_active = 0;
+		spin_unlock_irqrestore(&dsp_lock, flags);
+		/* MUST not be locked, because it waits until queue is done. */
+		cancel_work_sync(&dsp->workq);
+		spin_lock_irqsave(&dsp_lock, flags);
+		if (timer_pending(&dsp->tone.tl))
+			del_timer(&dsp->tone.tl);
+		skb_queue_purge(&dsp->sendq);
+		if (dsp_debug & DEBUG_DSP_CTRL)
+			printk(KERN_DEBUG "%s: releasing member %s\n",
+			       __func__, dsp->name);
+		dsp->b_active = 0;
+		dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be called
+					 here */
+		dsp_pipeline_destroy(&dsp->pipeline);
+
+		if (dsp_debug & DEBUG_DSP_CTRL)
+			printk(KERN_DEBUG "%s: remove & destroy object %s\n",
+			       __func__, dsp->name);
+		list_del(&dsp->list);
+		spin_unlock_irqrestore(&dsp_lock, flags);
+
+		if (dsp_debug & DEBUG_DSP_CTRL)
+			printk(KERN_DEBUG "%s: dsp instance released\n",
+			       __func__);
+		vfree(dsp);
+		module_put(THIS_MODULE);
+		break;
+	}
+	return 0;
+}
+
+static void
+dsp_send_bh(struct work_struct *work)
+{
+	struct dsp *dsp = container_of(work, struct dsp, workq);
+	struct sk_buff *skb;
+	struct mISDNhead	*hh;
+
+	if (dsp->hdlc && dsp->data_pending)
+		return; /* wait until data has been acknowledged */
+
+	/* send queued data */
+	while ((skb = skb_dequeue(&dsp->sendq))) {
+		/* in locked date, we must have still data in queue */
+		if (dsp->data_pending) {
+			if (dsp_debug & DEBUG_DSP_CORE)
+				printk(KERN_DEBUG "%s: fifo full %s, this is "
+				       "no bug!\n", __func__, dsp->name);
+			/* flush transparent data, if not acked */
+			dev_kfree_skb(skb);
+			continue;
+		}
+		hh = mISDN_HEAD_P(skb);
+		if (hh->prim == DL_DATA_REQ) {
+			/* send packet up */
+			if (dsp->up) {
+				if (dsp->up->send(dsp->up, skb))
+					dev_kfree_skb(skb);
+			} else
+				dev_kfree_skb(skb);
+		} else {
+			/* send packet down */
+			if (dsp->ch.peer) {
+				dsp->data_pending = 1;
+				if (dsp->ch.recv(dsp->ch.peer, skb)) {
+					dev_kfree_skb(skb);
+					dsp->data_pending = 0;
+				}
+			} else
+				dev_kfree_skb(skb);
+		}
+	}
+}
+
+static int
+dspcreate(struct channel_req *crq)
+{
+	struct dsp		*ndsp;
+	u_long		flags;
+
+	if (crq->protocol != ISDN_P_B_L2DSP
+	    && crq->protocol != ISDN_P_B_L2DSPHDLC)
+		return -EPROTONOSUPPORT;
+	ndsp = vzalloc(sizeof(struct dsp));
+	if (!ndsp) {
+		printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
+		return -ENOMEM;
+	}
+	if (dsp_debug & DEBUG_DSP_CTRL)
+		printk(KERN_DEBUG "%s: creating new dsp instance\n", __func__);
+
+	/* default enabled */
+	INIT_WORK(&ndsp->workq, (void *)dsp_send_bh);
+	skb_queue_head_init(&ndsp->sendq);
+	ndsp->ch.send = dsp_function;
+	ndsp->ch.ctrl = dsp_ctrl;
+	ndsp->up = crq->ch;
+	crq->ch = &ndsp->ch;
+	if (crq->protocol == ISDN_P_B_L2DSP) {
+		crq->protocol = ISDN_P_B_RAW;
+		ndsp->hdlc = 0;
+	} else {
+		crq->protocol = ISDN_P_B_HDLC;
+		ndsp->hdlc = 1;
+	}
+	if (!try_module_get(THIS_MODULE))
+		printk(KERN_WARNING "%s:cannot get module\n",
+		       __func__);
+
+	sprintf(ndsp->name, "DSP_C%x(0x%p)",
+		ndsp->up->st->dev->id + 1, ndsp);
+	/* set frame size to start */
+	ndsp->features.hfc_id = -1; /* current PCM id */
+	ndsp->features.pcm_id = -1; /* current PCM id */
+	ndsp->pcm_slot_rx = -1; /* current CPM slot */
+	ndsp->pcm_slot_tx = -1;
+	ndsp->pcm_bank_rx = -1;
+	ndsp->pcm_bank_tx = -1;
+	ndsp->hfc_conf = -1; /* current conference number */
+	/* set tone timer */
+	timer_setup(&ndsp->tone.tl, dsp_tone_timeout, 0);
+
+	if (dtmfthreshold < 20 || dtmfthreshold > 500)
+		dtmfthreshold = 200;
+	ndsp->dtmf.treshold = dtmfthreshold * 10000;
+
+	/* init pipeline append to list */
+	spin_lock_irqsave(&dsp_lock, flags);
+	dsp_pipeline_init(&ndsp->pipeline);
+	list_add_tail(&ndsp->list, &dsp_ilist);
+	spin_unlock_irqrestore(&dsp_lock, flags);
+
+	return 0;
+}
+
+
+static struct Bprotocol DSP = {
+	.Bprotocols = (1 << (ISDN_P_B_L2DSP & ISDN_P_B_MASK))
+	| (1 << (ISDN_P_B_L2DSPHDLC & ISDN_P_B_MASK)),
+	.name = "dsp",
+	.create = dspcreate
+};
+
+static int __init dsp_init(void)
+{
+	int err;
+	int tics;
+
+	printk(KERN_INFO "DSP module %s\n", mISDN_dsp_revision);
+
+	dsp_options = options;
+	dsp_debug = debug;
+
+	/* set packet size */
+	dsp_poll = poll;
+	if (dsp_poll) {
+		if (dsp_poll > MAX_POLL) {
+			printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
+			       "maximum.\n", __func__, poll, MAX_POLL);
+			err = -EINVAL;
+			return err;
+		}
+		if (dsp_poll < 8) {
+			printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
+			       "minimum.\n", __func__, dsp_poll);
+			err = -EINVAL;
+			return err;
+		}
+		dsp_tics = poll * HZ / 8000;
+		if (dsp_tics * 8000 != poll * HZ) {
+			printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
+			       "samples (0,125 ms). It is not a multiple of "
+			       "%d HZ.\n", poll, HZ);
+			err = -EINVAL;
+			return err;
+		}
+	} else {
+		poll = 8;
+		while (poll <= MAX_POLL) {
+			tics = (poll * HZ) / 8000;
+			if (tics * 8000 == poll * HZ) {
+				dsp_tics = tics;
+				dsp_poll = poll;
+				if (poll >= 64)
+					break;
+			}
+			poll++;
+		}
+	}
+	if (dsp_poll == 0) {
+		printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
+		       "clock that equals exactly the duration of 8-256 "
+		       "samples. (Choose kernel clock speed like 100, 250, "
+		       "300, 1000)\n");
+		err = -EINVAL;
+		return err;
+	}
+	printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
+	       "%d jiffies.\n", dsp_poll, dsp_tics);
+
+	/* init conversion tables */
+	dsp_audio_generate_law_tables();
+	dsp_silence = (dsp_options & DSP_OPT_ULAW) ? 0xff : 0x2a;
+	dsp_audio_law_to_s32 = (dsp_options & DSP_OPT_ULAW) ?
+		dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
+	dsp_audio_generate_s2law_table();
+	dsp_audio_generate_seven();
+	dsp_audio_generate_mix_table();
+	if (dsp_options & DSP_OPT_ULAW)
+		dsp_audio_generate_ulaw_samples();
+	dsp_audio_generate_volume_changes();
+
+	err = dsp_pipeline_module_init();
+	if (err) {
+		printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
+		       "error(%d)\n", err);
+		return err;
+	}
+
+	err = mISDN_register_Bprotocol(&DSP);
+	if (err) {
+		printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
+		return err;
+	}
+
+	/* set sample timer */
+	timer_setup(&dsp_spl_tl, dsp_cmx_send, 0);
+	dsp_spl_tl.expires = jiffies + dsp_tics;
+	dsp_spl_jiffies = dsp_spl_tl.expires;
+	add_timer(&dsp_spl_tl);
+
+	return 0;
+}
+
+
+static void __exit dsp_cleanup(void)
+{
+	mISDN_unregister_Bprotocol(&DSP);
+
+	del_timer_sync(&dsp_spl_tl);
+
+	if (!list_empty(&dsp_ilist)) {
+		printk(KERN_ERR "mISDN_dsp: Audio DSP object inst list not "
+		       "empty.\n");
+	}
+	if (!list_empty(&conf_ilist)) {
+		printk(KERN_ERR "mISDN_dsp: Conference list not empty. Not "
+		       "all memory freed.\n");
+	}
+
+	dsp_pipeline_module_exit();
+}
+
+module_init(dsp_init);
+module_exit(dsp_cleanup);
diff --git a/drivers/isdn/mISDN/dsp_dtmf.c b/drivers/isdn/mISDN/dsp_dtmf.c
new file mode 100644
index 000000000..642f30be5
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_dtmf.c
@@ -0,0 +1,313 @@
+/*
+ * DTMF decoder.
+ *
+ * Copyright            by Andreas Eversberg (jolly@eversberg.eu)
+ *			based on different decoders such as ISDN4Linux
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include "core.h"
+#include "dsp.h"
+
+#define NCOEFF            8     /* number of frequencies to be analyzed */
+
+/* For DTMF recognition:
+ * 2 * cos(2 * PI * k / N) precalculated for all k
+ */
+static u64 cos2pik[NCOEFF] =
+{
+	/* k << 15 (source: hfc-4s/8s documentation (www.colognechip.de)) */
+	55960, 53912, 51402, 48438, 38146, 32650, 26170, 18630
+};
+
+/* digit matrix */
+static char dtmf_matrix[4][4] =
+{
+	{'1', '2', '3', 'A'},
+	{'4', '5', '6', 'B'},
+	{'7', '8', '9', 'C'},
+	{'*', '0', '#', 'D'}
+};
+
+/* dtmf detection using goertzel algorithm
+ * init function
+ */
+void dsp_dtmf_goertzel_init(struct dsp *dsp)
+{
+	dsp->dtmf.size = 0;
+	dsp->dtmf.lastwhat = '\0';
+	dsp->dtmf.lastdigit = '\0';
+	dsp->dtmf.count = 0;
+}
+
+/* check for hardware or software features
+ */
+void dsp_dtmf_hardware(struct dsp *dsp)
+{
+	int hardware = 1;
+
+	if (!dsp->dtmf.enable)
+		return;
+
+	if (!dsp->features.hfc_dtmf)
+		hardware = 0;
+
+	/* check for volume change */
+	if (dsp->tx_volume) {
+		if (dsp_debug & DEBUG_DSP_DTMF)
+			printk(KERN_DEBUG "%s dsp %s cannot do hardware DTMF, "
+			       "because tx_volume is changed\n",
+			       __func__, dsp->name);
+		hardware = 0;
+	}
+	if (dsp->rx_volume) {
+		if (dsp_debug & DEBUG_DSP_DTMF)
+			printk(KERN_DEBUG "%s dsp %s cannot do hardware DTMF, "
+			       "because rx_volume is changed\n",
+			       __func__, dsp->name);
+		hardware = 0;
+	}
+	/* check if encryption is enabled */
+	if (dsp->bf_enable) {
+		if (dsp_debug & DEBUG_DSP_DTMF)
+			printk(KERN_DEBUG "%s dsp %s cannot do hardware DTMF, "
+			       "because encryption is enabled\n",
+			       __func__, dsp->name);
+		hardware = 0;
+	}
+	/* check if pipeline exists */
+	if (dsp->pipeline.inuse) {
+		if (dsp_debug & DEBUG_DSP_DTMF)
+			printk(KERN_DEBUG "%s dsp %s cannot do hardware DTMF, "
+			       "because pipeline exists.\n",
+			       __func__, dsp->name);
+		hardware = 0;
+	}
+
+	dsp->dtmf.hardware = hardware;
+	dsp->dtmf.software = !hardware;
+}
+
+
+/*************************************************************
+ * calculate the coefficients of the given sample and decode *
+ *************************************************************/
+
+/* the given sample is decoded. if the sample is not long enough for a
+ * complete frame, the decoding is finished and continued with the next
+ * call of this function.
+ *
+ * the algorithm is very good for detection with a minimum of errors. i
+ * tested it allot. it even works with very short tones (40ms). the only
+ * disadvantage is, that it doesn't work good with different volumes of both
+ * tones. this will happen, if accoustically coupled dialers are used.
+ * it sometimes detects tones during speech, which is normal for decoders.
+ * use sequences to given commands during calls.
+ *
+ * dtmf - points to a structure of the current dtmf state
+ * spl and len - the sample
+ * fmt - 0 = alaw, 1 = ulaw, 2 = coefficients from HFC DTMF hw-decoder
+ */
+
+u8
+*dsp_dtmf_goertzel_decode(struct dsp *dsp, u8 *data, int len, int fmt)
+{
+	u8 what;
+	int size;
+	signed short *buf;
+	s32 sk, sk1, sk2;
+	int k, n, i;
+	s32 *hfccoeff;
+	s32 result[NCOEFF], tresh, treshl;
+	int lowgroup, highgroup;
+	s64 cos2pik_;
+
+	dsp->dtmf.digits[0] = '\0';
+
+	/* Note: The function will loop until the buffer has not enough samples
+	 * left to decode a full frame.
+	 */
+again:
+	/* convert samples */
+	size = dsp->dtmf.size;
+	buf = dsp->dtmf.buffer;
+	switch (fmt) {
+	case 0: /* alaw */
+	case 1: /* ulaw */
+		while (size < DSP_DTMF_NPOINTS && len) {
+			buf[size++] = dsp_audio_law_to_s32[*data++];
+			len--;
+		}
+		break;
+
+	case 2: /* HFC coefficients */
+	default:
+		if (len < 64) {
+			if (len > 0)
+				printk(KERN_ERR "%s: coefficients have invalid "
+				       "size. (is=%d < must=%d)\n",
+				       __func__, len, 64);
+			return dsp->dtmf.digits;
+		}
+		hfccoeff = (s32 *)data;
+		for (k = 0; k < NCOEFF; k++) {
+			sk2 = (*hfccoeff++) >> 4;
+			sk = (*hfccoeff++) >> 4;
+			if (sk > 32767 || sk < -32767 || sk2 > 32767
+			    || sk2 < -32767)
+				printk(KERN_WARNING
+				       "DTMF-Detection overflow\n");
+			/* compute |X(k)|**2 */
+			result[k] =
+				(sk * sk) -
+				(((cos2pik[k] * sk) >> 15) * sk2) +
+				(sk2 * sk2);
+		}
+		data += 64;
+		len -= 64;
+		goto coefficients;
+		break;
+	}
+	dsp->dtmf.size = size;
+
+	if (size < DSP_DTMF_NPOINTS)
+		return dsp->dtmf.digits;
+
+	dsp->dtmf.size = 0;
+
+	/* now we have a full buffer of signed long samples - we do goertzel */
+	for (k = 0; k < NCOEFF; k++) {
+		sk = 0;
+		sk1 = 0;
+		sk2 = 0;
+		buf = dsp->dtmf.buffer;
+		cos2pik_ = cos2pik[k];
+		for (n = 0; n < DSP_DTMF_NPOINTS; n++) {
+			sk = ((cos2pik_ * sk1) >> 15) - sk2 + (*buf++);
+			sk2 = sk1;
+			sk1 = sk;
+		}
+		sk >>= 8;
+		sk2 >>= 8;
+		if (sk > 32767 || sk < -32767 || sk2 > 32767 || sk2 < -32767)
+			printk(KERN_WARNING "DTMF-Detection overflow\n");
+		/* compute |X(k)|**2 */
+		result[k] =
+			(sk * sk) -
+			(((cos2pik[k] * sk) >> 15) * sk2) +
+			(sk2 * sk2);
+	}
+
+	/* our (squared) coefficients have been calculated, we need to process
+	 * them.
+	 */
+coefficients:
+	tresh = 0;
+	for (i = 0; i < NCOEFF; i++) {
+		if (result[i] < 0)
+			result[i] = 0;
+		if (result[i] > dsp->dtmf.treshold) {
+			if (result[i] > tresh)
+				tresh = result[i];
+		}
+	}
+
+	if (tresh == 0) {
+		what = 0;
+		goto storedigit;
+	}
+
+	if (dsp_debug & DEBUG_DSP_DTMFCOEFF) {
+		s32 tresh_100 = tresh/100;
+
+		if (tresh_100 == 0) {
+			tresh_100 = 1;
+			printk(KERN_DEBUG
+				"tresh(%d) too small set tresh/100 to 1\n",
+				tresh);
+		}
+		printk(KERN_DEBUG "a %3d %3d %3d %3d %3d %3d %3d %3d"
+		       " tr:%3d r %3d %3d %3d %3d %3d %3d %3d %3d\n",
+		       result[0] / 10000, result[1] / 10000, result[2] / 10000,
+		       result[3] / 10000, result[4] / 10000, result[5] / 10000,
+		       result[6] / 10000, result[7] / 10000, tresh / 10000,
+		       result[0] / (tresh_100), result[1] / (tresh_100),
+		       result[2] / (tresh_100), result[3] / (tresh_100),
+		       result[4] / (tresh_100), result[5] / (tresh_100),
+		       result[6] / (tresh_100), result[7] / (tresh_100));
+	}
+
+	/* calc digit (lowgroup/highgroup) */
+	lowgroup = -1;
+	highgroup = -1;
+	treshl = tresh >> 3;  /* tones which are not on, must be below 9 dB */
+	tresh = tresh >> 2;  /* touchtones must match within 6 dB */
+	for (i = 0; i < NCOEFF; i++) {
+		if (result[i] < treshl)
+			continue;  /* ignore */
+		if (result[i] < tresh) {
+			lowgroup = -1;
+			highgroup = -1;
+			break;  /* noise in between */
+		}
+		/* good level found. This is allowed only one time per group */
+		if (i < NCOEFF / 2) {
+			/* lowgroup */
+			if (lowgroup >= 0) {
+				/* Bad. Another tone found. */
+				lowgroup = -1;
+				break;
+			} else
+				lowgroup = i;
+		} else {
+			/* higroup */
+			if (highgroup >= 0) {
+				/* Bad. Another tone found. */
+				highgroup = -1;
+				break;
+			} else
+				highgroup = i - (NCOEFF / 2);
+		}
+	}
+
+	/* get digit or null */
+	what = 0;
+	if (lowgroup >= 0 && highgroup >= 0)
+		what = dtmf_matrix[lowgroup][highgroup];
+
+storedigit:
+	if (what && (dsp_debug & DEBUG_DSP_DTMF))
+		printk(KERN_DEBUG "DTMF what: %c\n", what);
+
+	if (dsp->dtmf.lastwhat != what)
+		dsp->dtmf.count = 0;
+
+	/* the tone (or no tone) must remain 3 times without change */
+	if (dsp->dtmf.count == 2) {
+		if (dsp->dtmf.lastdigit != what) {
+			dsp->dtmf.lastdigit = what;
+			if (what) {
+				if (dsp_debug & DEBUG_DSP_DTMF)
+					printk(KERN_DEBUG "DTMF digit: %c\n",
+					       what);
+				if ((strlen(dsp->dtmf.digits) + 1)
+				    < sizeof(dsp->dtmf.digits)) {
+					dsp->dtmf.digits[strlen(
+							dsp->dtmf.digits) + 1] = '\0';
+					dsp->dtmf.digits[strlen(
+							dsp->dtmf.digits)] = what;
+				}
+			}
+		}
+	} else
+		dsp->dtmf.count++;
+
+	dsp->dtmf.lastwhat = what;
+
+	goto again;
+}
diff --git a/drivers/isdn/mISDN/dsp_ecdis.h b/drivers/isdn/mISDN/dsp_ecdis.h
new file mode 100644
index 000000000..4bcdf3218
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_ecdis.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * ec_disable_detector.h - A detector which should eventually meet the
+ *                         G.164/G.165 requirements for detecting the
+ *                         2100Hz echo cancellor disable tone.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2001 Steve Underwood
+ *
+ * All rights reserved.
+ */
+
+#include "dsp_biquad.h"
+
+struct ec_disable_detector_state {
+	struct biquad2_state notch;
+	int notch_level;
+	int channel_level;
+	int tone_present;
+	int tone_cycle_duration;
+	int good_cycles;
+	int hit;
+};
+
+
+#define FALSE 0
+#define TRUE (!FALSE)
+
+static inline void
+echo_can_disable_detector_init(struct ec_disable_detector_state *det)
+{
+	/* Elliptic notch */
+	/* This is actually centred at 2095Hz, but gets the balance we want, due
+	   to the asymmetric walls of the notch */
+	biquad2_init(&det->notch,
+		     (int32_t)(-0.7600000 * 32768.0),
+		     (int32_t)(-0.1183852 * 32768.0),
+		     (int32_t)(-0.5104039 * 32768.0),
+		     (int32_t)(0.1567596 * 32768.0),
+		     (int32_t)(1.0000000 * 32768.0));
+
+	det->channel_level = 0;
+	det->notch_level = 0;
+	det->tone_present = FALSE;
+	det->tone_cycle_duration = 0;
+	det->good_cycles = 0;
+	det->hit = 0;
+}
+/*- End of function --------------------------------------------------------*/
+
+static inline int
+echo_can_disable_detector_update(struct ec_disable_detector_state *det,
+				 int16_t amp)
+{
+	int16_t notched;
+
+	notched = biquad2(&det->notch, amp);
+	/* Estimate the overall energy in the channel, and the energy in
+	   the notch (i.e. overall channel energy - tone energy => noise).
+	   Use abs instead of multiply for speed (is it really faster?).
+	   Damp the overall energy a little more for a stable result.
+	   Damp the notch energy a little less, so we don't damp out the
+	   blip every time the phase reverses */
+	det->channel_level += ((abs(amp) - det->channel_level) >> 5);
+	det->notch_level += ((abs(notched) - det->notch_level) >> 4);
+	if (det->channel_level > 280) {
+		/* There is adequate energy in the channel.
+		   Is it mostly at 2100Hz? */
+		if (det->notch_level * 6 < det->channel_level) {
+			/* The notch says yes, so we have the tone. */
+			if (!det->tone_present) {
+				/* Do we get a kick every 450+-25ms? */
+				if (det->tone_cycle_duration >= 425 * 8
+				    && det->tone_cycle_duration <= 475 * 8) {
+					det->good_cycles++;
+					if (det->good_cycles > 2)
+						det->hit = TRUE;
+				}
+				det->tone_cycle_duration = 0;
+			}
+			det->tone_present = TRUE;
+		} else
+			det->tone_present = FALSE;
+		det->tone_cycle_duration++;
+	} else {
+		det->tone_present = FALSE;
+		det->tone_cycle_duration = 0;
+		det->good_cycles = 0;
+	}
+	return det->hit;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/
diff --git a/drivers/isdn/mISDN/dsp_hwec.c b/drivers/isdn/mISDN/dsp_hwec.c
new file mode 100644
index 000000000..0b3f29195
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_hwec.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * dsp_hwec.c:
+ * builtin mISDN dsp pipeline element for enabling the hw echocanceller
+ *
+ * Copyright (C) 2007, Nadi Sarrar
+ *
+ * Nadi Sarrar <nadi@beronet.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/mISDNdsp.h>
+#include <linux/mISDNif.h>
+#include "core.h"
+#include "dsp.h"
+#include "dsp_hwec.h"
+
+static struct mISDN_dsp_element_arg args[] = {
+	{ "deftaps", "128", "Set the number of taps of cancellation." },
+};
+
+static struct mISDN_dsp_element dsp_hwec_p = {
+	.name = "hwec",
+	.new = NULL,
+	.free = NULL,
+	.process_tx = NULL,
+	.process_rx = NULL,
+	.num_args = ARRAY_SIZE(args),
+	.args = args,
+};
+struct mISDN_dsp_element *dsp_hwec = &dsp_hwec_p;
+
+void dsp_hwec_enable(struct dsp *dsp, const char *arg)
+{
+	int deftaps = 128,
+		len;
+	struct mISDN_ctrl_req	cq;
+
+	if (!dsp) {
+		printk(KERN_ERR "%s: failed to enable hwec: dsp is NULL\n",
+		       __func__);
+		return;
+	}
+
+	if (!arg)
+		goto _do;
+
+	len = strlen(arg);
+	if (!len)
+		goto _do;
+
+	{
+		char *dup, *tok, *name, *val;
+		int tmp;
+
+		dup = kstrdup(arg, GFP_ATOMIC);
+		if (!dup)
+			return;
+
+		while ((tok = strsep(&dup, ","))) {
+			if (!strlen(tok))
+				continue;
+			name = strsep(&tok, "=");
+			val = tok;
+
+			if (!val)
+				continue;
+
+			if (!strcmp(name, "deftaps")) {
+				if (sscanf(val, "%d", &tmp) == 1)
+					deftaps = tmp;
+			}
+		}
+
+		kfree(dup);
+	}
+
+_do:
+	printk(KERN_DEBUG "%s: enabling hwec with deftaps=%d\n",
+	       __func__, deftaps);
+	memset(&cq, 0, sizeof(cq));
+	cq.op = MISDN_CTRL_HFC_ECHOCAN_ON;
+	cq.p1 = deftaps;
+	if (!dsp->ch.peer->ctrl(&dsp->ch, CONTROL_CHANNEL, &cq)) {
+		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
+		       __func__);
+		return;
+	}
+}
+
+void dsp_hwec_disable(struct dsp *dsp)
+{
+	struct mISDN_ctrl_req	cq;
+
+	if (!dsp) {
+		printk(KERN_ERR "%s: failed to disable hwec: dsp is NULL\n",
+		       __func__);
+		return;
+	}
+
+	printk(KERN_DEBUG "%s: disabling hwec\n", __func__);
+	memset(&cq, 0, sizeof(cq));
+	cq.op = MISDN_CTRL_HFC_ECHOCAN_OFF;
+	if (!dsp->ch.peer->ctrl(&dsp->ch, CONTROL_CHANNEL, &cq)) {
+		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
+		       __func__);
+		return;
+	}
+}
+
+int dsp_hwec_init(void)
+{
+	mISDN_dsp_element_register(dsp_hwec);
+
+	return 0;
+}
+
+void dsp_hwec_exit(void)
+{
+	mISDN_dsp_element_unregister(dsp_hwec);
+}
diff --git a/drivers/isdn/mISDN/dsp_hwec.h b/drivers/isdn/mISDN/dsp_hwec.h
new file mode 100644
index 000000000..c9cb0ea24
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_hwec.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * dsp_hwec.h
+ */
+
+extern struct mISDN_dsp_element *dsp_hwec;
+extern void dsp_hwec_enable(struct dsp *dsp, const char *arg);
+extern void dsp_hwec_disable(struct dsp *dsp);
+extern int  dsp_hwec_init(void);
+extern void dsp_hwec_exit(void);
diff --git a/drivers/isdn/mISDN/dsp_pipeline.c b/drivers/isdn/mISDN/dsp_pipeline.c
new file mode 100644
index 000000000..cfbcd9e97
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_pipeline.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * dsp_pipeline.c: pipelined audio processing
+ *
+ * Copyright (C) 2007, Nadi Sarrar
+ *
+ * Nadi Sarrar <nadi@beronet.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/string.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include <linux/export.h>
+#include "dsp.h"
+#include "dsp_hwec.h"
+
+struct dsp_pipeline_entry {
+	struct mISDN_dsp_element *elem;
+	void                *p;
+	struct list_head     list;
+};
+struct dsp_element_entry {
+	struct mISDN_dsp_element *elem;
+	struct device	     dev;
+	struct list_head     list;
+};
+
+static LIST_HEAD(dsp_elements);
+
+/* sysfs */
+static struct class *elements_class;
+
+static ssize_t
+attr_show_args(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct mISDN_dsp_element *elem = dev_get_drvdata(dev);
+	int i;
+	char *p = buf;
+
+	*buf = 0;
+	for (i = 0; i < elem->num_args; i++)
+		p += sprintf(p, "Name:        %s\n%s%s%sDescription: %s\n\n",
+			     elem->args[i].name,
+			     elem->args[i].def ? "Default:     " : "",
+			     elem->args[i].def ? elem->args[i].def : "",
+			     elem->args[i].def ? "\n" : "",
+			     elem->args[i].desc);
+
+	return p - buf;
+}
+
+static struct device_attribute element_attributes[] = {
+	__ATTR(args, 0444, attr_show_args, NULL),
+};
+
+static void
+mISDN_dsp_dev_release(struct device *dev)
+{
+	struct dsp_element_entry *entry =
+		container_of(dev, struct dsp_element_entry, dev);
+	list_del(&entry->list);
+	kfree(entry);
+}
+
+int mISDN_dsp_element_register(struct mISDN_dsp_element *elem)
+{
+	struct dsp_element_entry *entry;
+	int ret, i;
+
+	if (!elem)
+		return -EINVAL;
+
+	entry = kzalloc(sizeof(struct dsp_element_entry), GFP_ATOMIC);
+	if (!entry)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&entry->list);
+	entry->elem = elem;
+
+	entry->dev.class = elements_class;
+	entry->dev.release = mISDN_dsp_dev_release;
+	dev_set_drvdata(&entry->dev, elem);
+	dev_set_name(&entry->dev, "%s", elem->name);
+	ret = device_register(&entry->dev);
+	if (ret) {
+		printk(KERN_ERR "%s: failed to register %s\n",
+		       __func__, elem->name);
+		goto err1;
+	}
+	list_add_tail(&entry->list, &dsp_elements);
+
+	for (i = 0; i < ARRAY_SIZE(element_attributes); ++i) {
+		ret = device_create_file(&entry->dev,
+					 &element_attributes[i]);
+		if (ret) {
+			printk(KERN_ERR "%s: failed to create device file\n",
+			       __func__);
+			goto err2;
+		}
+	}
+
+	return 0;
+
+err2:
+	device_unregister(&entry->dev);
+	return ret;
+err1:
+	put_device(&entry->dev);
+	return ret;
+}
+EXPORT_SYMBOL(mISDN_dsp_element_register);
+
+void mISDN_dsp_element_unregister(struct mISDN_dsp_element *elem)
+{
+	struct dsp_element_entry *entry, *n;
+
+	if (!elem)
+		return;
+
+	list_for_each_entry_safe(entry, n, &dsp_elements, list)
+		if (entry->elem == elem) {
+			device_unregister(&entry->dev);
+			return;
+		}
+	printk(KERN_ERR "%s: element %s not in list.\n", __func__, elem->name);
+}
+EXPORT_SYMBOL(mISDN_dsp_element_unregister);
+
+int dsp_pipeline_module_init(void)
+{
+	elements_class = class_create(THIS_MODULE, "dsp_pipeline");
+	if (IS_ERR(elements_class))
+		return PTR_ERR(elements_class);
+
+	dsp_hwec_init();
+
+	return 0;
+}
+
+void dsp_pipeline_module_exit(void)
+{
+	struct dsp_element_entry *entry, *n;
+
+	dsp_hwec_exit();
+
+	class_destroy(elements_class);
+
+	list_for_each_entry_safe(entry, n, &dsp_elements, list) {
+		list_del(&entry->list);
+		printk(KERN_WARNING "%s: element was still registered: %s\n",
+		       __func__, entry->elem->name);
+		kfree(entry);
+	}
+}
+
+int dsp_pipeline_init(struct dsp_pipeline *pipeline)
+{
+	if (!pipeline)
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&pipeline->list);
+
+	return 0;
+}
+
+static inline void _dsp_pipeline_destroy(struct dsp_pipeline *pipeline)
+{
+	struct dsp_pipeline_entry *entry, *n;
+
+	list_for_each_entry_safe(entry, n, &pipeline->list, list) {
+		list_del(&entry->list);
+		if (entry->elem == dsp_hwec)
+			dsp_hwec_disable(container_of(pipeline, struct dsp,
+						      pipeline));
+		else
+			entry->elem->free(entry->p);
+		kfree(entry);
+	}
+}
+
+void dsp_pipeline_destroy(struct dsp_pipeline *pipeline)
+{
+
+	if (!pipeline)
+		return;
+
+	_dsp_pipeline_destroy(pipeline);
+}
+
+int dsp_pipeline_build(struct dsp_pipeline *pipeline, const char *cfg)
+{
+	int found = 0;
+	char *dup, *next, *tok, *name, *args;
+	struct dsp_element_entry *entry, *n;
+	struct dsp_pipeline_entry *pipeline_entry;
+	struct mISDN_dsp_element *elem;
+
+	if (!pipeline)
+		return -EINVAL;
+
+	if (!list_empty(&pipeline->list))
+		_dsp_pipeline_destroy(pipeline);
+
+	dup = next = kstrdup(cfg, GFP_ATOMIC);
+	if (!dup)
+		return 0;
+	while ((tok = strsep(&next, "|"))) {
+		if (!strlen(tok))
+			continue;
+		name = strsep(&tok, "(");
+		args = strsep(&tok, ")");
+		if (args && !*args)
+			args = NULL;
+
+		list_for_each_entry_safe(entry, n, &dsp_elements, list)
+			if (!strcmp(entry->elem->name, name)) {
+				elem = entry->elem;
+
+				pipeline_entry = kmalloc(sizeof(struct
+								dsp_pipeline_entry), GFP_ATOMIC);
+				if (!pipeline_entry) {
+					printk(KERN_ERR "%s: failed to add "
+					       "entry to pipeline: %s (out of "
+					       "memory)\n", __func__, elem->name);
+					goto _out;
+				}
+				pipeline_entry->elem = elem;
+
+				if (elem == dsp_hwec) {
+					/* This is a hack to make the hwec
+					   available as a pipeline module */
+					dsp_hwec_enable(container_of(pipeline,
+								     struct dsp, pipeline), args);
+					list_add_tail(&pipeline_entry->list,
+						      &pipeline->list);
+				} else {
+					pipeline_entry->p = elem->new(args);
+					if (pipeline_entry->p) {
+						list_add_tail(&pipeline_entry->
+							      list, &pipeline->list);
+					} else {
+						printk(KERN_ERR "%s: failed "
+						       "to add entry to pipeline: "
+						       "%s (new() returned NULL)\n",
+						       __func__, elem->name);
+						kfree(pipeline_entry);
+					}
+				}
+				found = 1;
+				break;
+			}
+
+		if (found)
+			found = 0;
+		else
+			printk(KERN_ERR "%s: element not found, skipping: "
+			       "%s\n", __func__, name);
+	}
+
+_out:
+	if (!list_empty(&pipeline->list))
+		pipeline->inuse = 1;
+	else
+		pipeline->inuse = 0;
+
+	kfree(dup);
+	return 0;
+}
+
+void dsp_pipeline_process_tx(struct dsp_pipeline *pipeline, u8 *data, int len)
+{
+	struct dsp_pipeline_entry *entry;
+
+	if (!pipeline)
+		return;
+
+	list_for_each_entry(entry, &pipeline->list, list)
+		if (entry->elem->process_tx)
+			entry->elem->process_tx(entry->p, data, len);
+}
+
+void dsp_pipeline_process_rx(struct dsp_pipeline *pipeline, u8 *data, int len,
+			     unsigned int txlen)
+{
+	struct dsp_pipeline_entry *entry;
+
+	if (!pipeline)
+		return;
+
+	list_for_each_entry_reverse(entry, &pipeline->list, list)
+		if (entry->elem->process_rx)
+			entry->elem->process_rx(entry->p, data, len, txlen);
+}
diff --git a/drivers/isdn/mISDN/dsp_tones.c b/drivers/isdn/mISDN/dsp_tones.c
new file mode 100644
index 000000000..8389e2105
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_tones.c
@@ -0,0 +1,550 @@
+/*
+ * Audio support data for ISDN4Linux.
+ *
+ * Copyright Andreas Eversberg (jolly@eversberg.eu)
+ *
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#include <linux/gfp.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include "core.h"
+#include "dsp.h"
+
+
+#define DATA_S sample_silence
+#define SIZE_S (&sizeof_silence)
+#define DATA_GA sample_german_all
+#define SIZE_GA (&sizeof_german_all)
+#define DATA_GO sample_german_old
+#define SIZE_GO (&sizeof_german_old)
+#define DATA_DT sample_american_dialtone
+#define SIZE_DT (&sizeof_american_dialtone)
+#define DATA_RI sample_american_ringing
+#define SIZE_RI (&sizeof_american_ringing)
+#define DATA_BU sample_american_busy
+#define SIZE_BU (&sizeof_american_busy)
+#define DATA_S1 sample_special1
+#define SIZE_S1 (&sizeof_special1)
+#define DATA_S2 sample_special2
+#define SIZE_S2 (&sizeof_special2)
+#define DATA_S3 sample_special3
+#define SIZE_S3 (&sizeof_special3)
+
+/***************/
+/* tones loops */
+/***************/
+
+/* all tones are alaw encoded */
+/* the last sample+1 is in phase with the first sample. the error is low */
+
+static u8 sample_german_all[] = {
+	0x80, 0xab, 0x81, 0x6d, 0xfd, 0xdd, 0x5d, 0x9d,
+	0x4d, 0xd1, 0x89, 0x88, 0xd0, 0x4c, 0x9c, 0x5c,
+	0xdc, 0xfc, 0x6c,
+	0x80, 0xab, 0x81, 0x6d, 0xfd, 0xdd, 0x5d, 0x9d,
+	0x4d, 0xd1, 0x89, 0x88, 0xd0, 0x4c, 0x9c, 0x5c,
+	0xdc, 0xfc, 0x6c,
+	0x80, 0xab, 0x81, 0x6d, 0xfd, 0xdd, 0x5d, 0x9d,
+	0x4d, 0xd1, 0x89, 0x88, 0xd0, 0x4c, 0x9c, 0x5c,
+	0xdc, 0xfc, 0x6c,
+	0x80, 0xab, 0x81, 0x6d, 0xfd, 0xdd, 0x5d, 0x9d,
+	0x4d, 0xd1, 0x89, 0x88, 0xd0, 0x4c, 0x9c, 0x5c,
+	0xdc, 0xfc, 0x6c,
+};
+static u32 sizeof_german_all = sizeof(sample_german_all);
+
+static u8 sample_german_old[] = {
+	0xec, 0x68, 0xe1, 0x6d, 0x6d, 0x91, 0x51, 0xed,
+	0x6d, 0x01, 0x1e, 0x10, 0x0c, 0x90, 0x60, 0x70,
+	0x8c,
+	0xec, 0x68, 0xe1, 0x6d, 0x6d, 0x91, 0x51, 0xed,
+	0x6d, 0x01, 0x1e, 0x10, 0x0c, 0x90, 0x60, 0x70,
+	0x8c,
+	0xec, 0x68, 0xe1, 0x6d, 0x6d, 0x91, 0x51, 0xed,
+	0x6d, 0x01, 0x1e, 0x10, 0x0c, 0x90, 0x60, 0x70,
+	0x8c,
+	0xec, 0x68, 0xe1, 0x6d, 0x6d, 0x91, 0x51, 0xed,
+	0x6d, 0x01, 0x1e, 0x10, 0x0c, 0x90, 0x60, 0x70,
+	0x8c,
+};
+static u32 sizeof_german_old = sizeof(sample_german_old);
+
+static u8 sample_american_dialtone[] = {
+	0x2a, 0x18, 0x90, 0x6c, 0x4c, 0xbc, 0x4c, 0x6c,
+	0x10, 0x58, 0x32, 0xb9, 0x31, 0x2d, 0x8d, 0x0d,
+	0x8d, 0x2d, 0x31, 0x99, 0x0f, 0x28, 0x60, 0xf0,
+	0xd0, 0x50, 0xd0, 0x30, 0x60, 0x08, 0x8e, 0x67,
+	0x09, 0x19, 0x21, 0xe1, 0xd9, 0xb9, 0x29, 0x67,
+	0x83, 0x02, 0xce, 0xbe, 0xee, 0x1a, 0x1b, 0xef,
+	0xbf, 0xcf, 0x03, 0x82, 0x66, 0x28, 0xb8, 0xd8,
+	0xe0, 0x20, 0x18, 0x08, 0x66, 0x8f, 0x09, 0x61,
+	0x31, 0xd1, 0x51, 0xd1, 0xf1, 0x61, 0x29, 0x0e,
+	0x98, 0x30, 0x2c, 0x8c, 0x0c, 0x8c, 0x2c, 0x30,
+	0xb8, 0x33, 0x59, 0x11, 0x6d, 0x4d, 0xbd, 0x4d,
+	0x6d, 0x91, 0x19,
+};
+static u32 sizeof_american_dialtone = sizeof(sample_american_dialtone);
+
+static u8 sample_american_ringing[] = {
+	0x2a, 0xe0, 0xac, 0x0c, 0xbc, 0x4c, 0x8c, 0x90,
+	0x48, 0xc7, 0xc1, 0xed, 0xcd, 0x4d, 0xcd, 0xed,
+	0xc1, 0xb7, 0x08, 0x30, 0xec, 0xcc, 0xcc, 0x8c,
+	0x10, 0x58, 0x1a, 0x99, 0x71, 0xed, 0x8d, 0x8d,
+	0x2d, 0x41, 0x89, 0x9e, 0x20, 0x70, 0x2c, 0xec,
+	0x2c, 0x70, 0x20, 0x86, 0x77, 0xe1, 0x31, 0x11,
+	0xd1, 0xf1, 0x81, 0x09, 0xa3, 0x56, 0x58, 0x00,
+	0x40, 0xc0, 0x60, 0x38, 0x46, 0x43, 0x57, 0x39,
+	0xd9, 0x59, 0x99, 0xc9, 0x77, 0x2f, 0x2e, 0xc6,
+	0xd6, 0x28, 0xd6, 0x36, 0x26, 0x2e, 0x8a, 0xa3,
+	0x43, 0x63, 0x4b, 0x4a, 0x62, 0x42, 0xa2, 0x8b,
+	0x2f, 0x27, 0x37, 0xd7, 0x29, 0xd7, 0xc7, 0x2f,
+	0x2e, 0x76, 0xc8, 0x98, 0x58, 0xd8, 0x38, 0x56,
+	0x42, 0x47, 0x39, 0x61, 0xc1, 0x41, 0x01, 0x59,
+	0x57, 0xa2, 0x08, 0x80, 0xf0, 0xd0, 0x10, 0x30,
+	0xe0, 0x76, 0x87, 0x21, 0x71, 0x2d, 0xed, 0x2d,
+	0x71, 0x21, 0x9f, 0x88, 0x40, 0x2c, 0x8c, 0x8c,
+	0xec, 0x70, 0x98, 0x1b, 0x59, 0x11, 0x8d, 0xcd,
+	0xcd, 0xed, 0x31, 0x09, 0xb6, 0xc0, 0xec, 0xcc,
+	0x4c, 0xcc, 0xec, 0xc0, 0xc6, 0x49, 0x91, 0x8d,
+	0x4d, 0xbd, 0x0d, 0xad, 0xe1,
+};
+static u32 sizeof_american_ringing = sizeof(sample_american_ringing);
+
+static u8 sample_american_busy[] = {
+	0x2a, 0x00, 0x6c, 0x4c, 0x4c, 0x6c, 0xb0, 0x66,
+	0x99, 0x11, 0x6d, 0x8d, 0x2d, 0x41, 0xd7, 0x96,
+	0x60, 0xf0, 0x70, 0x40, 0x58, 0xf6, 0x53, 0x57,
+	0x09, 0x89, 0xd7, 0x5f, 0xe3, 0x2a, 0xe3, 0x5f,
+	0xd7, 0x89, 0x09, 0x57, 0x53, 0xf6, 0x58, 0x40,
+	0x70, 0xf0, 0x60, 0x96, 0xd7, 0x41, 0x2d, 0x8d,
+	0x6d, 0x11, 0x99, 0x66, 0xb0, 0x6c, 0x4c, 0x4c,
+	0x6c, 0x00, 0x2a, 0x01, 0x6d, 0x4d, 0x4d, 0x6d,
+	0xb1, 0x67, 0x98, 0x10, 0x6c, 0x8c, 0x2c, 0x40,
+	0xd6, 0x97, 0x61, 0xf1, 0x71, 0x41, 0x59, 0xf7,
+	0x52, 0x56, 0x08, 0x88, 0xd6, 0x5e, 0xe2, 0x2a,
+	0xe2, 0x5e, 0xd6, 0x88, 0x08, 0x56, 0x52, 0xf7,
+	0x59, 0x41, 0x71, 0xf1, 0x61, 0x97, 0xd6, 0x40,
+	0x2c, 0x8c, 0x6c, 0x10, 0x98, 0x67, 0xb1, 0x6d,
+	0x4d, 0x4d, 0x6d, 0x01,
+};
+static u32 sizeof_american_busy = sizeof(sample_american_busy);
+
+static u8 sample_special1[] = {
+	0x2a, 0x2c, 0xbc, 0x6c, 0xd6, 0x71, 0xbd, 0x0d,
+	0xd9, 0x80, 0xcc, 0x4c, 0x40, 0x39, 0x0d, 0xbd,
+	0x11, 0x86, 0xec, 0xbc, 0xec, 0x0e, 0x51, 0xbd,
+	0x8d, 0x89, 0x30, 0x4c, 0xcc, 0xe0, 0xe1, 0xcd,
+	0x4d, 0x31, 0x88, 0x8c, 0xbc, 0x50, 0x0f, 0xed,
+	0xbd, 0xed, 0x87, 0x10, 0xbc, 0x0c, 0x38, 0x41,
+	0x4d, 0xcd, 0x81, 0xd8, 0x0c, 0xbc, 0x70, 0xd7,
+	0x6d, 0xbd, 0x2d,
+};
+static u32 sizeof_special1 = sizeof(sample_special1);
+
+static u8 sample_special2[] = {
+	0x2a, 0xcc, 0x8c, 0xd7, 0x4d, 0x2d, 0x18, 0xbc,
+	0x10, 0xc1, 0xbd, 0xc1, 0x10, 0xbc, 0x18, 0x2d,
+	0x4d, 0xd7, 0x8c, 0xcc, 0x2a, 0xcd, 0x8d, 0xd6,
+	0x4c, 0x2c, 0x19, 0xbd, 0x11, 0xc0, 0xbc, 0xc0,
+	0x11, 0xbd, 0x19, 0x2c, 0x4c, 0xd6, 0x8d, 0xcd,
+	0x2a, 0xcc, 0x8c, 0xd7, 0x4d, 0x2d, 0x18, 0xbc,
+	0x10, 0xc1, 0xbd, 0xc1, 0x10, 0xbc, 0x18, 0x2d,
+	0x4d, 0xd7, 0x8c, 0xcc, 0x2a, 0xcd, 0x8d, 0xd6,
+	0x4c, 0x2c, 0x19, 0xbd, 0x11, 0xc0, 0xbc, 0xc0,
+	0x11, 0xbd, 0x19, 0x2c, 0x4c, 0xd6, 0x8d, 0xcd,
+};
+static u32 sizeof_special2 = sizeof(sample_special2);
+
+static u8 sample_special3[] = {
+	0x2a, 0xbc, 0x18, 0xcd, 0x11, 0x2c, 0x8c, 0xc1,
+	0x4d, 0xd6, 0xbc, 0xd6, 0x4d, 0xc1, 0x8c, 0x2c,
+	0x11, 0xcd, 0x18, 0xbc, 0x2a, 0xbd, 0x19, 0xcc,
+	0x10, 0x2d, 0x8d, 0xc0, 0x4c, 0xd7, 0xbd, 0xd7,
+	0x4c, 0xc0, 0x8d, 0x2d, 0x10, 0xcc, 0x19, 0xbd,
+	0x2a, 0xbc, 0x18, 0xcd, 0x11, 0x2c, 0x8c, 0xc1,
+	0x4d, 0xd6, 0xbc, 0xd6, 0x4d, 0xc1, 0x8c, 0x2c,
+	0x11, 0xcd, 0x18, 0xbc, 0x2a, 0xbd, 0x19, 0xcc,
+	0x10, 0x2d, 0x8d, 0xc0, 0x4c, 0xd7, 0xbd, 0xd7,
+	0x4c, 0xc0, 0x8d, 0x2d, 0x10, 0xcc, 0x19, 0xbd,
+};
+static u32 sizeof_special3 = sizeof(sample_special3);
+
+static u8 sample_silence[] = {
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+	0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a,
+};
+static u32 sizeof_silence = sizeof(sample_silence);
+
+struct tones_samples {
+	u32 *len;
+	u8 *data;
+};
+static struct
+tones_samples samples[] = {
+	{&sizeof_german_all, sample_german_all},
+	{&sizeof_german_old, sample_german_old},
+	{&sizeof_american_dialtone, sample_american_dialtone},
+	{&sizeof_american_ringing, sample_american_ringing},
+	{&sizeof_american_busy, sample_american_busy},
+	{&sizeof_special1, sample_special1},
+	{&sizeof_special2, sample_special2},
+	{&sizeof_special3, sample_special3},
+	{NULL, NULL},
+};
+
+/***********************************
+ * generate ulaw from alaw samples *
+ ***********************************/
+
+void
+dsp_audio_generate_ulaw_samples(void)
+{
+	int i, j;
+
+	i = 0;
+	while (samples[i].len) {
+		j = 0;
+		while (j < (*samples[i].len)) {
+			samples[i].data[j] =
+				dsp_audio_alaw_to_ulaw[samples[i].data[j]];
+			j++;
+		}
+		i++;
+	}
+}
+
+
+/****************************
+ * tone sequence definition *
+ ****************************/
+
+static struct pattern {
+	int tone;
+	u8 *data[10];
+	u32 *siz[10];
+	u32 seq[10];
+} pattern[] = {
+	{TONE_GERMAN_DIALTONE,
+	 {DATA_GA, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {1900, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDDIALTONE,
+	 {DATA_GO, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {1998, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_DIALTONE,
+	 {DATA_DT, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_DT, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {8000, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_DIALPBX,
+	 {DATA_GA, DATA_S, DATA_GA, DATA_S, DATA_GA, DATA_S, NULL, NULL, NULL,
+	  NULL},
+	 {SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, NULL, NULL, NULL,
+	  NULL},
+	 {2000, 2000, 2000, 2000, 2000, 12000, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDDIALPBX,
+	 {DATA_GO, DATA_S, DATA_GO, DATA_S, DATA_GO, DATA_S, NULL, NULL, NULL,
+	  NULL},
+	 {SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, NULL, NULL, NULL,
+	  NULL},
+	 {2000, 2000, 2000, 2000, 2000, 12000, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_DIALPBX,
+	 {DATA_DT, DATA_S, DATA_DT, DATA_S, DATA_DT, DATA_S, NULL, NULL, NULL,
+	  NULL},
+	 {SIZE_DT, SIZE_S, SIZE_DT, SIZE_S, SIZE_DT, SIZE_S, NULL, NULL, NULL,
+	  NULL},
+	 {2000, 2000, 2000, 2000, 2000, 12000, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_RINGING,
+	 {DATA_GA, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {8000, 32000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDRINGING,
+	 {DATA_GO, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {8000, 40000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_RINGING,
+	 {DATA_RI, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_RI, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {8000, 32000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_RINGPBX,
+	 {DATA_GA, DATA_S, DATA_GA, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDRINGPBX,
+	 {DATA_GO, DATA_S, DATA_GO, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_RINGPBX,
+	 {DATA_RI, DATA_S, DATA_RI, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_RI, SIZE_S, SIZE_RI, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_BUSY,
+	 {DATA_GA, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDBUSY,
+	 {DATA_GO, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {1000, 5000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_BUSY,
+	 {DATA_BU, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_BU, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_HANGUP,
+	 {DATA_GA, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDHANGUP,
+	 {DATA_GO, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {1000, 5000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_HANGUP,
+	 {DATA_DT, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_DT, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {8000, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_SPECIAL_INFO,
+	 {DATA_S1, DATA_S2, DATA_S3, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_S1, SIZE_S2, SIZE_S3, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {2666, 2666, 2666, 8002, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_GASSENBESETZT,
+	 {DATA_GA, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GA, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {2000, 2000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_AUFSCHALTTON,
+	 {DATA_GO, DATA_S, DATA_GO, DATA_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {1000, 5000, 1000, 17000, 0, 0, 0, 0, 0, 0} },
+
+	{0,
+	 {NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL},
+	 {0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
+/******************
+ * copy tone data *
+ ******************/
+
+/* an sk_buff is generated from the number of samples needed.
+ * the count will be changed and may begin from 0 each pattern period.
+ * the clue is to precalculate the pointers and legths to use only one
+ * memcpy per function call, or two memcpy if the tone sequence changes.
+ *
+ * pattern - the type of the pattern
+ * count - the sample from the beginning of the pattern (phase)
+ * len - the number of bytes
+ *
+ * return - the sk_buff with the sample
+ *
+ * if tones has finished (e.g. knocking tone), dsp->tones is turned off
+ */
+void dsp_tone_copy(struct dsp *dsp, u8 *data, int len)
+{
+	int index, count, start, num;
+	struct pattern *pat;
+	struct dsp_tone *tone = &dsp->tone;
+
+	/* if we have no tone, we copy silence */
+	if (!tone->tone) {
+		memset(data, dsp_silence, len);
+		return;
+	}
+
+	/* process pattern */
+	pat = (struct pattern *)tone->pattern;
+	/* points to the current pattern */
+	index = tone->index; /* gives current sequence index */
+	count = tone->count; /* gives current sample */
+
+	/* copy sample */
+	while (len) {
+		/* find sample to start with */
+		while (42) {
+			/* wrap around */
+			if (!pat->seq[index]) {
+				count = 0;
+				index = 0;
+			}
+			/* check if we are currently playing this tone */
+			if (count < pat->seq[index])
+				break;
+			if (dsp_debug & DEBUG_DSP_TONE)
+				printk(KERN_DEBUG "%s: reaching next sequence "
+				       "(index=%d)\n", __func__, index);
+			count -= pat->seq[index];
+			index++;
+		}
+		/* calculate start and number of samples */
+		start = count % (*(pat->siz[index]));
+		num = len;
+		if (num + count > pat->seq[index])
+			num = pat->seq[index] - count;
+		if (num + start > (*(pat->siz[index])))
+			num = (*(pat->siz[index])) - start;
+		/* copy memory */
+		memcpy(data, pat->data[index] + start, num);
+		/* reduce length */
+		data += num;
+		count += num;
+		len -= num;
+	}
+	tone->index = index;
+	tone->count = count;
+
+	/* return sk_buff */
+	return;
+}
+
+
+/*******************************
+ * send HW message to hfc card *
+ *******************************/
+
+static void
+dsp_tone_hw_message(struct dsp *dsp, u8 *sample, int len)
+{
+	struct sk_buff *nskb;
+
+	/* unlocking is not required, because we don't expect a response */
+	nskb = _alloc_mISDN_skb(PH_CONTROL_REQ,
+				(len) ? HFC_SPL_LOOP_ON : HFC_SPL_LOOP_OFF, len, sample,
+				GFP_ATOMIC);
+	if (nskb) {
+		if (dsp->ch.peer) {
+			if (dsp->ch.recv(dsp->ch.peer, nskb))
+				dev_kfree_skb(nskb);
+		} else
+			dev_kfree_skb(nskb);
+	}
+}
+
+
+/*****************
+ * timer expires *
+ *****************/
+void
+dsp_tone_timeout(struct timer_list *t)
+{
+	struct dsp *dsp = from_timer(dsp, t, tone.tl);
+	struct dsp_tone *tone = &dsp->tone;
+	struct pattern *pat = (struct pattern *)tone->pattern;
+	int index = tone->index;
+
+	if (!tone->tone)
+		return;
+
+	index++;
+	if (!pat->seq[index])
+		index = 0;
+	tone->index = index;
+
+	/* set next tone */
+	if (pat->data[index] == DATA_S)
+		dsp_tone_hw_message(dsp, NULL, 0);
+	else
+		dsp_tone_hw_message(dsp, pat->data[index], *(pat->siz[index]));
+	/* set timer */
+	tone->tl.expires = jiffies + (pat->seq[index] * HZ) / 8000;
+	add_timer(&tone->tl);
+}
+
+
+/********************
+ * set/release tone *
+ ********************/
+
+/*
+ * tones are relaized by streaming or by special loop commands if supported
+ * by hardware. when hardware is used, the patterns will be controlled by
+ * timers.
+ */
+int
+dsp_tone(struct dsp *dsp, int tone)
+{
+	struct pattern *pat;
+	int i;
+	struct dsp_tone *tonet = &dsp->tone;
+
+	tonet->software = 0;
+	tonet->hardware = 0;
+
+	/* we turn off the tone */
+	if (!tone) {
+		if (dsp->features.hfc_loops && timer_pending(&tonet->tl))
+			del_timer(&tonet->tl);
+		if (dsp->features.hfc_loops)
+			dsp_tone_hw_message(dsp, NULL, 0);
+		tonet->tone = 0;
+		return 0;
+	}
+
+	pat = NULL;
+	i = 0;
+	while (pattern[i].tone) {
+		if (pattern[i].tone == tone) {
+			pat = &pattern[i];
+			break;
+		}
+		i++;
+	}
+	if (!pat) {
+		printk(KERN_WARNING "dsp: given tone 0x%x is invalid\n", tone);
+		return -EINVAL;
+	}
+	if (dsp_debug & DEBUG_DSP_TONE)
+		printk(KERN_DEBUG "%s: now starting tone %d (index=%d)\n",
+		       __func__, tone, 0);
+	tonet->tone = tone;
+	tonet->pattern = pat;
+	tonet->index = 0;
+	tonet->count = 0;
+
+	if (dsp->features.hfc_loops) {
+		tonet->hardware = 1;
+		/* set first tone */
+		dsp_tone_hw_message(dsp, pat->data[0], *(pat->siz[0]));
+		/* set timer */
+		if (timer_pending(&tonet->tl))
+			del_timer(&tonet->tl);
+		tonet->tl.expires = jiffies + (pat->seq[0] * HZ) / 8000;
+		add_timer(&tonet->tl);
+	} else {
+		tonet->software = 1;
+	}
+
+	return 0;
+}
diff --git a/drivers/isdn/mISDN/fsm.c b/drivers/isdn/mISDN/fsm.c
new file mode 100644
index 000000000..7c5c2ca6c
--- /dev/null
+++ b/drivers/isdn/mISDN/fsm.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * finite state machine implementation
+ *
+ * Author       Karsten Keil <kkeil@novell.com>
+ *
+ * Thanks to    Jan den Ouden
+ *              Fritz Elfert
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include "fsm.h"
+
+#define FSM_TIMER_DEBUG 0
+
+int
+mISDN_FsmNew(struct Fsm *fsm,
+	     struct FsmNode *fnlist, int fncount)
+{
+	int i;
+
+	fsm->jumpmatrix =
+		kzalloc(array3_size(sizeof(FSMFNPTR), fsm->state_count,
+				    fsm->event_count),
+			GFP_KERNEL);
+	if (fsm->jumpmatrix == NULL)
+		return -ENOMEM;
+
+	for (i = 0; i < fncount; i++)
+		if ((fnlist[i].state >= fsm->state_count) ||
+		    (fnlist[i].event >= fsm->event_count)) {
+			printk(KERN_ERR
+			       "mISDN_FsmNew Error: %d st(%ld/%ld) ev(%ld/%ld)\n",
+			       i, (long)fnlist[i].state, (long)fsm->state_count,
+			       (long)fnlist[i].event, (long)fsm->event_count);
+		} else
+			fsm->jumpmatrix[fsm->state_count * fnlist[i].event +
+					fnlist[i].state] = (FSMFNPTR) fnlist[i].routine;
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_FsmNew);
+
+void
+mISDN_FsmFree(struct Fsm *fsm)
+{
+	kfree((void *) fsm->jumpmatrix);
+}
+EXPORT_SYMBOL(mISDN_FsmFree);
+
+int
+mISDN_FsmEvent(struct FsmInst *fi, int event, void *arg)
+{
+	FSMFNPTR r;
+
+	if ((fi->state >= fi->fsm->state_count) ||
+	    (event >= fi->fsm->event_count)) {
+		printk(KERN_ERR
+		       "mISDN_FsmEvent Error st(%ld/%ld) ev(%d/%ld)\n",
+		       (long)fi->state, (long)fi->fsm->state_count, event,
+		       (long)fi->fsm->event_count);
+		return 1;
+	}
+	r = fi->fsm->jumpmatrix[fi->fsm->state_count * event + fi->state];
+	if (r) {
+		if (fi->debug)
+			fi->printdebug(fi, "State %s Event %s",
+				       fi->fsm->strState[fi->state],
+				       fi->fsm->strEvent[event]);
+		r(fi, event, arg);
+		return 0;
+	} else {
+		if (fi->debug)
+			fi->printdebug(fi, "State %s Event %s no action",
+				       fi->fsm->strState[fi->state],
+				       fi->fsm->strEvent[event]);
+		return 1;
+	}
+}
+EXPORT_SYMBOL(mISDN_FsmEvent);
+
+void
+mISDN_FsmChangeState(struct FsmInst *fi, int newstate)
+{
+	fi->state = newstate;
+	if (fi->debug)
+		fi->printdebug(fi, "ChangeState %s",
+			       fi->fsm->strState[newstate]);
+}
+EXPORT_SYMBOL(mISDN_FsmChangeState);
+
+static void
+FsmExpireTimer(struct timer_list *t)
+{
+	struct FsmTimer *ft = from_timer(ft, t, tl);
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmExpireTimer %lx", (long) ft);
+#endif
+	mISDN_FsmEvent(ft->fi, ft->event, ft->arg);
+}
+
+void
+mISDN_FsmInitTimer(struct FsmInst *fi, struct FsmTimer *ft)
+{
+	ft->fi = fi;
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "mISDN_FsmInitTimer %lx", (long) ft);
+#endif
+	timer_setup(&ft->tl, FsmExpireTimer, 0);
+}
+EXPORT_SYMBOL(mISDN_FsmInitTimer);
+
+void
+mISDN_FsmDelTimer(struct FsmTimer *ft, int where)
+{
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "mISDN_FsmDelTimer %lx %d",
+				   (long) ft, where);
+#endif
+	del_timer(&ft->tl);
+}
+EXPORT_SYMBOL(mISDN_FsmDelTimer);
+
+int
+mISDN_FsmAddTimer(struct FsmTimer *ft,
+		  int millisec, int event, void *arg, int where)
+{
+
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "mISDN_FsmAddTimer %lx %d %d",
+				   (long) ft, millisec, where);
+#endif
+
+	if (timer_pending(&ft->tl)) {
+		if (ft->fi->debug) {
+			printk(KERN_WARNING
+			       "mISDN_FsmAddTimer: timer already active!\n");
+			ft->fi->printdebug(ft->fi,
+					   "mISDN_FsmAddTimer already active!");
+		}
+		return -1;
+	}
+	ft->event = event;
+	ft->arg = arg;
+	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
+	add_timer(&ft->tl);
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_FsmAddTimer);
+
+void
+mISDN_FsmRestartTimer(struct FsmTimer *ft,
+		      int millisec, int event, void *arg, int where)
+{
+
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "mISDN_FsmRestartTimer %lx %d %d",
+				   (long) ft, millisec, where);
+#endif
+
+	if (timer_pending(&ft->tl))
+		del_timer(&ft->tl);
+	ft->event = event;
+	ft->arg = arg;
+	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
+	add_timer(&ft->tl);
+}
+EXPORT_SYMBOL(mISDN_FsmRestartTimer);
diff --git a/drivers/isdn/mISDN/fsm.h b/drivers/isdn/mISDN/fsm.h
new file mode 100644
index 000000000..211554b99
--- /dev/null
+++ b/drivers/isdn/mISDN/fsm.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *
+ * Author       Karsten Keil <kkeil@novell.com>
+ *
+ * Thanks to    Jan den Ouden
+ *              Fritz Elfert
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#ifndef _MISDN_FSM_H
+#define _MISDN_FSM_H
+
+#include <linux/timer.h>
+
+/* Statemachine */
+
+struct FsmInst;
+
+typedef void (*FSMFNPTR)(struct FsmInst *, int, void *);
+
+struct Fsm {
+	FSMFNPTR *jumpmatrix;
+	int state_count, event_count;
+	char **strEvent, **strState;
+};
+
+struct FsmInst {
+	struct Fsm *fsm;
+	int state;
+	int debug;
+	void *userdata;
+	int userint;
+	void (*printdebug) (struct FsmInst *, char *, ...);
+};
+
+struct FsmNode {
+	int state, event;
+	void (*routine) (struct FsmInst *, int, void *);
+};
+
+struct FsmTimer {
+	struct FsmInst *fi;
+	struct timer_list tl;
+	int event;
+	void *arg;
+};
+
+extern int mISDN_FsmNew(struct Fsm *, struct FsmNode *, int);
+extern void mISDN_FsmFree(struct Fsm *);
+extern int mISDN_FsmEvent(struct FsmInst *, int , void *);
+extern void mISDN_FsmChangeState(struct FsmInst *, int);
+extern void mISDN_FsmInitTimer(struct FsmInst *, struct FsmTimer *);
+extern int mISDN_FsmAddTimer(struct FsmTimer *, int, int, void *, int);
+extern void mISDN_FsmRestartTimer(struct FsmTimer *, int, int, void *, int);
+extern void mISDN_FsmDelTimer(struct FsmTimer *, int);
+
+#endif
diff --git a/drivers/isdn/mISDN/hwchannel.c b/drivers/isdn/mISDN/hwchannel.c
new file mode 100644
index 000000000..8c93af06e
--- /dev/null
+++ b/drivers/isdn/mISDN/hwchannel.c
@@ -0,0 +1,516 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/mISDNhw.h>
+
+static void
+dchannel_bh(struct work_struct *ws)
+{
+	struct dchannel	*dch  = container_of(ws, struct dchannel, workq);
+	struct sk_buff	*skb;
+	int		err;
+
+	if (test_and_clear_bit(FLG_RECVQUEUE, &dch->Flags)) {
+		while ((skb = skb_dequeue(&dch->rqueue))) {
+			if (likely(dch->dev.D.peer)) {
+				err = dch->dev.D.recv(dch->dev.D.peer, skb);
+				if (err)
+					dev_kfree_skb(skb);
+			} else
+				dev_kfree_skb(skb);
+		}
+	}
+	if (test_and_clear_bit(FLG_PHCHANGE, &dch->Flags)) {
+		if (dch->phfunc)
+			dch->phfunc(dch);
+	}
+}
+
+static void
+bchannel_bh(struct work_struct *ws)
+{
+	struct bchannel	*bch  = container_of(ws, struct bchannel, workq);
+	struct sk_buff	*skb;
+	int		err;
+
+	if (test_and_clear_bit(FLG_RECVQUEUE, &bch->Flags)) {
+		while ((skb = skb_dequeue(&bch->rqueue))) {
+			bch->rcount--;
+			if (likely(bch->ch.peer)) {
+				err = bch->ch.recv(bch->ch.peer, skb);
+				if (err)
+					dev_kfree_skb(skb);
+			} else
+				dev_kfree_skb(skb);
+		}
+	}
+}
+
+int
+mISDN_initdchannel(struct dchannel *ch, int maxlen, void *phf)
+{
+	test_and_set_bit(FLG_HDLC, &ch->Flags);
+	ch->maxlen = maxlen;
+	ch->hw = NULL;
+	ch->rx_skb = NULL;
+	ch->tx_skb = NULL;
+	ch->tx_idx = 0;
+	ch->phfunc = phf;
+	skb_queue_head_init(&ch->squeue);
+	skb_queue_head_init(&ch->rqueue);
+	INIT_LIST_HEAD(&ch->dev.bchannels);
+	INIT_WORK(&ch->workq, dchannel_bh);
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_initdchannel);
+
+int
+mISDN_initbchannel(struct bchannel *ch, unsigned short maxlen,
+		   unsigned short minlen)
+{
+	ch->Flags = 0;
+	ch->minlen = minlen;
+	ch->next_minlen = minlen;
+	ch->init_minlen = minlen;
+	ch->maxlen = maxlen;
+	ch->next_maxlen = maxlen;
+	ch->init_maxlen = maxlen;
+	ch->hw = NULL;
+	ch->rx_skb = NULL;
+	ch->tx_skb = NULL;
+	ch->tx_idx = 0;
+	skb_queue_head_init(&ch->rqueue);
+	ch->rcount = 0;
+	ch->next_skb = NULL;
+	INIT_WORK(&ch->workq, bchannel_bh);
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_initbchannel);
+
+int
+mISDN_freedchannel(struct dchannel *ch)
+{
+	if (ch->tx_skb) {
+		dev_kfree_skb(ch->tx_skb);
+		ch->tx_skb = NULL;
+	}
+	if (ch->rx_skb) {
+		dev_kfree_skb(ch->rx_skb);
+		ch->rx_skb = NULL;
+	}
+	skb_queue_purge(&ch->squeue);
+	skb_queue_purge(&ch->rqueue);
+	flush_work(&ch->workq);
+	return 0;
+}
+EXPORT_SYMBOL(mISDN_freedchannel);
+
+void
+mISDN_clear_bchannel(struct bchannel *ch)
+{
+	if (ch->tx_skb) {
+		dev_kfree_skb(ch->tx_skb);
+		ch->tx_skb = NULL;
+	}
+	ch->tx_idx = 0;
+	if (ch->rx_skb) {
+		dev_kfree_skb(ch->rx_skb);
+		ch->rx_skb = NULL;
+	}
+	if (ch->next_skb) {
+		dev_kfree_skb(ch->next_skb);
+		ch->next_skb = NULL;
+	}
+	test_and_clear_bit(FLG_TX_BUSY, &ch->Flags);
+	test_and_clear_bit(FLG_TX_NEXT, &ch->Flags);
+	test_and_clear_bit(FLG_ACTIVE, &ch->Flags);
+	test_and_clear_bit(FLG_FILLEMPTY, &ch->Flags);
+	test_and_clear_bit(FLG_TX_EMPTY, &ch->Flags);
+	test_and_clear_bit(FLG_RX_OFF, &ch->Flags);
+	ch->dropcnt = 0;
+	ch->minlen = ch->init_minlen;
+	ch->next_minlen = ch->init_minlen;
+	ch->maxlen = ch->init_maxlen;
+	ch->next_maxlen = ch->init_maxlen;
+	skb_queue_purge(&ch->rqueue);
+	ch->rcount = 0;
+}
+EXPORT_SYMBOL(mISDN_clear_bchannel);
+
+void
+mISDN_freebchannel(struct bchannel *ch)
+{
+	cancel_work_sync(&ch->workq);
+	mISDN_clear_bchannel(ch);
+}
+EXPORT_SYMBOL(mISDN_freebchannel);
+
+int
+mISDN_ctrl_bchannel(struct bchannel *bch, struct mISDN_ctrl_req *cq)
+{
+	int ret = 0;
+
+	switch (cq->op) {
+	case MISDN_CTRL_GETOP:
+		cq->op = MISDN_CTRL_RX_BUFFER | MISDN_CTRL_FILL_EMPTY |
+			 MISDN_CTRL_RX_OFF;
+		break;
+	case MISDN_CTRL_FILL_EMPTY:
+		if (cq->p1) {
+			memset(bch->fill, cq->p2 & 0xff, MISDN_BCH_FILL_SIZE);
+			test_and_set_bit(FLG_FILLEMPTY, &bch->Flags);
+		} else {
+			test_and_clear_bit(FLG_FILLEMPTY, &bch->Flags);
+		}
+		break;
+	case MISDN_CTRL_RX_OFF:
+		/* read back dropped byte count */
+		cq->p2 = bch->dropcnt;
+		if (cq->p1)
+			test_and_set_bit(FLG_RX_OFF, &bch->Flags);
+		else
+			test_and_clear_bit(FLG_RX_OFF, &bch->Flags);
+		bch->dropcnt = 0;
+		break;
+	case MISDN_CTRL_RX_BUFFER:
+		if (cq->p2 > MISDN_CTRL_RX_SIZE_IGNORE)
+			bch->next_maxlen = cq->p2;
+		if (cq->p1 > MISDN_CTRL_RX_SIZE_IGNORE)
+			bch->next_minlen = cq->p1;
+		/* we return the old values */
+		cq->p1 = bch->minlen;
+		cq->p2 = bch->maxlen;
+		break;
+	default:
+		pr_info("mISDN unhandled control %x operation\n", cq->op);
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(mISDN_ctrl_bchannel);
+
+static inline u_int
+get_sapi_tei(u_char *p)
+{
+	u_int	sapi, tei;
+
+	sapi = *p >> 2;
+	tei = p[1] >> 1;
+	return sapi | (tei << 8);
+}
+
+void
+recv_Dchannel(struct dchannel *dch)
+{
+	struct mISDNhead *hh;
+
+	if (dch->rx_skb->len < 2) { /* at least 2 for sapi / tei */
+		dev_kfree_skb(dch->rx_skb);
+		dch->rx_skb = NULL;
+		return;
+	}
+	hh = mISDN_HEAD_P(dch->rx_skb);
+	hh->prim = PH_DATA_IND;
+	hh->id = get_sapi_tei(dch->rx_skb->data);
+	skb_queue_tail(&dch->rqueue, dch->rx_skb);
+	dch->rx_skb = NULL;
+	schedule_event(dch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Dchannel);
+
+void
+recv_Echannel(struct dchannel *ech, struct dchannel *dch)
+{
+	struct mISDNhead *hh;
+
+	if (ech->rx_skb->len < 2) { /* at least 2 for sapi / tei */
+		dev_kfree_skb(ech->rx_skb);
+		ech->rx_skb = NULL;
+		return;
+	}
+	hh = mISDN_HEAD_P(ech->rx_skb);
+	hh->prim = PH_DATA_E_IND;
+	hh->id = get_sapi_tei(ech->rx_skb->data);
+	skb_queue_tail(&dch->rqueue, ech->rx_skb);
+	ech->rx_skb = NULL;
+	schedule_event(dch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Echannel);
+
+void
+recv_Bchannel(struct bchannel *bch, unsigned int id, bool force)
+{
+	struct mISDNhead *hh;
+
+	/* if allocation did fail upper functions still may call us */
+	if (unlikely(!bch->rx_skb))
+		return;
+	if (unlikely(!bch->rx_skb->len)) {
+		/* we have no data to send - this may happen after recovery
+		 * from overflow or too small allocation.
+		 * We need to free the buffer here */
+		dev_kfree_skb(bch->rx_skb);
+		bch->rx_skb = NULL;
+	} else {
+		if (test_bit(FLG_TRANSPARENT, &bch->Flags) &&
+		    (bch->rx_skb->len < bch->minlen) && !force)
+				return;
+		hh = mISDN_HEAD_P(bch->rx_skb);
+		hh->prim = PH_DATA_IND;
+		hh->id = id;
+		if (bch->rcount >= 64) {
+			printk(KERN_WARNING
+			       "B%d receive queue overflow - flushing!\n",
+			       bch->nr);
+			skb_queue_purge(&bch->rqueue);
+		}
+		bch->rcount++;
+		skb_queue_tail(&bch->rqueue, bch->rx_skb);
+		bch->rx_skb = NULL;
+		schedule_event(bch, FLG_RECVQUEUE);
+	}
+}
+EXPORT_SYMBOL(recv_Bchannel);
+
+void
+recv_Dchannel_skb(struct dchannel *dch, struct sk_buff *skb)
+{
+	skb_queue_tail(&dch->rqueue, skb);
+	schedule_event(dch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Dchannel_skb);
+
+void
+recv_Bchannel_skb(struct bchannel *bch, struct sk_buff *skb)
+{
+	if (bch->rcount >= 64) {
+		printk(KERN_WARNING "B-channel %p receive queue overflow, "
+		       "flushing!\n", bch);
+		skb_queue_purge(&bch->rqueue);
+		bch->rcount = 0;
+	}
+	bch->rcount++;
+	skb_queue_tail(&bch->rqueue, skb);
+	schedule_event(bch, FLG_RECVQUEUE);
+}
+EXPORT_SYMBOL(recv_Bchannel_skb);
+
+static void
+confirm_Dsend(struct dchannel *dch)
+{
+	struct sk_buff	*skb;
+
+	skb = _alloc_mISDN_skb(PH_DATA_CNF, mISDN_HEAD_ID(dch->tx_skb),
+			       0, NULL, GFP_ATOMIC);
+	if (!skb) {
+		printk(KERN_ERR "%s: no skb id %x\n", __func__,
+		       mISDN_HEAD_ID(dch->tx_skb));
+		return;
+	}
+	skb_queue_tail(&dch->rqueue, skb);
+	schedule_event(dch, FLG_RECVQUEUE);
+}
+
+int
+get_next_dframe(struct dchannel *dch)
+{
+	dch->tx_idx = 0;
+	dch->tx_skb = skb_dequeue(&dch->squeue);
+	if (dch->tx_skb) {
+		confirm_Dsend(dch);
+		return 1;
+	}
+	dch->tx_skb = NULL;
+	test_and_clear_bit(FLG_TX_BUSY, &dch->Flags);
+	return 0;
+}
+EXPORT_SYMBOL(get_next_dframe);
+
+static void
+confirm_Bsend(struct bchannel *bch)
+{
+	struct sk_buff	*skb;
+
+	if (bch->rcount >= 64) {
+		printk(KERN_WARNING "B-channel %p receive queue overflow, "
+		       "flushing!\n", bch);
+		skb_queue_purge(&bch->rqueue);
+		bch->rcount = 0;
+	}
+	skb = _alloc_mISDN_skb(PH_DATA_CNF, mISDN_HEAD_ID(bch->tx_skb),
+			       0, NULL, GFP_ATOMIC);
+	if (!skb) {
+		printk(KERN_ERR "%s: no skb id %x\n", __func__,
+		       mISDN_HEAD_ID(bch->tx_skb));
+		return;
+	}
+	bch->rcount++;
+	skb_queue_tail(&bch->rqueue, skb);
+	schedule_event(bch, FLG_RECVQUEUE);
+}
+
+int
+get_next_bframe(struct bchannel *bch)
+{
+	bch->tx_idx = 0;
+	if (test_bit(FLG_TX_NEXT, &bch->Flags)) {
+		bch->tx_skb = bch->next_skb;
+		if (bch->tx_skb) {
+			bch->next_skb = NULL;
+			test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
+			/* confirm imediately to allow next data */
+			confirm_Bsend(bch);
+			return 1;
+		} else {
+			test_and_clear_bit(FLG_TX_NEXT, &bch->Flags);
+			printk(KERN_WARNING "B TX_NEXT without skb\n");
+		}
+	}
+	bch->tx_skb = NULL;
+	test_and_clear_bit(FLG_TX_BUSY, &bch->Flags);
+	return 0;
+}
+EXPORT_SYMBOL(get_next_bframe);
+
+void
+queue_ch_frame(struct mISDNchannel *ch, u_int pr, int id, struct sk_buff *skb)
+{
+	struct mISDNhead *hh;
+
+	if (!skb) {
+		_queue_data(ch, pr, id, 0, NULL, GFP_ATOMIC);
+	} else {
+		if (ch->peer) {
+			hh = mISDN_HEAD_P(skb);
+			hh->prim = pr;
+			hh->id = id;
+			if (!ch->recv(ch->peer, skb))
+				return;
+		}
+		dev_kfree_skb(skb);
+	}
+}
+EXPORT_SYMBOL(queue_ch_frame);
+
+int
+dchannel_senddata(struct dchannel *ch, struct sk_buff *skb)
+{
+	/* check oversize */
+	if (skb->len <= 0) {
+		printk(KERN_WARNING "%s: skb too small\n", __func__);
+		return -EINVAL;
+	}
+	if (skb->len > ch->maxlen) {
+		printk(KERN_WARNING "%s: skb too large(%d/%d)\n",
+		       __func__, skb->len, ch->maxlen);
+		return -EINVAL;
+	}
+	/* HW lock must be obtained */
+	if (test_and_set_bit(FLG_TX_BUSY, &ch->Flags)) {
+		skb_queue_tail(&ch->squeue, skb);
+		return 0;
+	} else {
+		/* write to fifo */
+		ch->tx_skb = skb;
+		ch->tx_idx = 0;
+		return 1;
+	}
+}
+EXPORT_SYMBOL(dchannel_senddata);
+
+int
+bchannel_senddata(struct bchannel *ch, struct sk_buff *skb)
+{
+
+	/* check oversize */
+	if (skb->len <= 0) {
+		printk(KERN_WARNING "%s: skb too small\n", __func__);
+		return -EINVAL;
+	}
+	if (skb->len > ch->maxlen) {
+		printk(KERN_WARNING "%s: skb too large(%d/%d)\n",
+		       __func__, skb->len, ch->maxlen);
+		return -EINVAL;
+	}
+	/* HW lock must be obtained */
+	/* check for pending next_skb */
+	if (ch->next_skb) {
+		printk(KERN_WARNING
+		       "%s: next_skb exist ERROR (skb->len=%d next_skb->len=%d)\n",
+		       __func__, skb->len, ch->next_skb->len);
+		return -EBUSY;
+	}
+	if (test_and_set_bit(FLG_TX_BUSY, &ch->Flags)) {
+		test_and_set_bit(FLG_TX_NEXT, &ch->Flags);
+		ch->next_skb = skb;
+		return 0;
+	} else {
+		/* write to fifo */
+		ch->tx_skb = skb;
+		ch->tx_idx = 0;
+		confirm_Bsend(ch);
+		return 1;
+	}
+}
+EXPORT_SYMBOL(bchannel_senddata);
+
+/* The function allocates a new receive skb on demand with a size for the
+ * requirements of the current protocol. It returns the tailroom of the
+ * receive skb or an error.
+ */
+int
+bchannel_get_rxbuf(struct bchannel *bch, int reqlen)
+{
+	int len;
+
+	if (bch->rx_skb) {
+		len = skb_tailroom(bch->rx_skb);
+		if (len < reqlen) {
+			pr_warn("B%d no space for %d (only %d) bytes\n",
+				bch->nr, reqlen, len);
+			if (test_bit(FLG_TRANSPARENT, &bch->Flags)) {
+				/* send what we have now and try a new buffer */
+				recv_Bchannel(bch, 0, true);
+			} else {
+				/* on HDLC we have to drop too big frames */
+				return -EMSGSIZE;
+			}
+		} else {
+			return len;
+		}
+	}
+	/* update current min/max length first */
+	if (unlikely(bch->maxlen != bch->next_maxlen))
+		bch->maxlen = bch->next_maxlen;
+	if (unlikely(bch->minlen != bch->next_minlen))
+		bch->minlen = bch->next_minlen;
+	if (unlikely(reqlen > bch->maxlen))
+		return -EMSGSIZE;
+	if (test_bit(FLG_TRANSPARENT, &bch->Flags)) {
+		if (reqlen >= bch->minlen) {
+			len = reqlen;
+		} else {
+			len = 2 * bch->minlen;
+			if (len > bch->maxlen)
+				len = bch->maxlen;
+		}
+	} else {
+		/* with HDLC we do not know the length yet */
+		len = bch->maxlen;
+	}
+	bch->rx_skb = mI_alloc_skb(len, GFP_ATOMIC);
+	if (!bch->rx_skb) {
+		pr_warn("B%d receive no memory for %d bytes\n", bch->nr, len);
+		len = -ENOMEM;
+	}
+	return len;
+}
+EXPORT_SYMBOL(bchannel_get_rxbuf);
diff --git a/drivers/isdn/mISDN/l1oip.h b/drivers/isdn/mISDN/l1oip.h
new file mode 100644
index 000000000..48133d022
--- /dev/null
+++ b/drivers/isdn/mISDN/l1oip.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * see notice in l1oip.c
+ */
+
+/* debugging */
+#define DEBUG_L1OIP_INIT	0x00010000
+#define DEBUG_L1OIP_SOCKET	0x00020000
+#define DEBUG_L1OIP_MGR		0x00040000
+#define DEBUG_L1OIP_MSG		0x00080000
+
+/* enable to disorder received bchannels by sequence 2143658798... */
+/*
+  #define REORDER_DEBUG
+*/
+
+/* frames */
+#define L1OIP_MAX_LEN		2048		/* max packet size form l2 */
+#define L1OIP_MAX_PERFRAME	1400		/* max data size in one frame */
+
+
+/* timers */
+#define L1OIP_KEEPALIVE		15
+#define L1OIP_TIMEOUT		65
+
+
+/* socket */
+#define L1OIP_DEFAULTPORT	931
+
+
+/* channel structure */
+struct l1oip_chan {
+	struct dchannel		*dch;
+	struct bchannel		*bch;
+	u32			tx_counter;	/* counts xmit bytes/packets */
+	u32			rx_counter;	/* counts recv bytes/packets */
+	u32			codecstate;	/* used by codec to save data */
+#ifdef REORDER_DEBUG
+	int			disorder_flag;
+	struct sk_buff		*disorder_skb;
+	u32			disorder_cnt;
+#endif
+};
+
+
+/* card structure */
+struct l1oip {
+	struct list_head        list;
+
+	/* card */
+	int			registered;	/* if registered with mISDN */
+	char			name[MISDN_MAX_IDLEN];
+	int			idx;		/* card index */
+	int			pri;		/* 1=pri, 0=bri */
+	int			d_idx;		/* current dchannel number */
+	int			b_num;		/* number of bchannels */
+	u32			id;		/* id of connection */
+	int			ondemand;	/* if transmis. is on demand */
+	int			bundle;		/* bundle channels in one frm */
+	int			codec;		/* codec to use for transmis. */
+	int			limit;		/* limit number of bchannels */
+	bool			shutdown;	/* if card is released */
+
+	/* timer */
+	struct timer_list	keep_tl;
+	struct timer_list	timeout_tl;
+	int			timeout_on;
+	struct work_struct	workq;
+
+	/* socket */
+	struct socket		*socket;	/* if set, socket is created */
+	struct completion	socket_complete;/* completion of sock thread */
+	struct task_struct	*socket_thread;
+	spinlock_t		socket_lock;	/* access sock outside thread */
+	u32			remoteip;	/* if all set, ip is assigned */
+	u16			localport;	/* must always be set */
+	u16			remoteport;	/* must always be set */
+	struct sockaddr_in	sin_local;	/* local socket name */
+	struct sockaddr_in	sin_remote;	/* remote socket name */
+	struct msghdr		sendmsg;	/* ip message to send */
+	struct kvec		sendiov;	/* iov for message */
+
+	/* frame */
+	struct l1oip_chan	chan[128];	/* channel instances */
+};
+
+extern int l1oip_law_to_4bit(u8 *data, int len, u8 *result, u32 *state);
+extern int l1oip_4bit_to_law(u8 *data, int len, u8 *result);
+extern int l1oip_alaw_to_ulaw(u8 *data, int len, u8 *result);
+extern int l1oip_ulaw_to_alaw(u8 *data, int len, u8 *result);
+extern void l1oip_4bit_free(void);
+extern int l1oip_4bit_alloc(int ulaw);
diff --git a/drivers/isdn/mISDN/l1oip_codec.c b/drivers/isdn/mISDN/l1oip_codec.c
new file mode 100644
index 000000000..1059234fb
--- /dev/null
+++ b/drivers/isdn/mISDN/l1oip_codec.c
@@ -0,0 +1,358 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+
+ * l1oip_codec.c  generic codec using lookup table
+ *  -> conversion from a-Law to u-Law
+ *  -> conversion from u-Law to a-Law
+ *  -> compression by reducing the number of sample resolution to 4
+ *
+ * NOTE: It is not compatible with any standard codec like ADPCM.
+ *
+ * Author	Andreas Eversberg (jolly@eversberg.eu)
+ *
+
+ */
+
+/*
+
+  How the codec works:
+  --------------------
+
+  The volume is increased to increase the dynamic range of the audio signal.
+  Each sample is converted to a-LAW with only 16 steps of level resolution.
+  A pair of two samples are stored in one byte.
+
+  The first byte is stored in the upper bits, the second byte is stored in the
+  lower bits.
+
+  To speed up compression and decompression, two lookup tables are formed:
+
+  - 16 bits index for two samples (law encoded) with 8 bit compressed result.
+  - 8 bits index for one compressed data with 16 bits decompressed result.
+
+  NOTE: The bytes are handled as they are law-encoded.
+
+*/
+
+#include <linux/vmalloc.h>
+#include <linux/mISDNif.h>
+#include <linux/in.h>
+#include "core.h"
+#include "l1oip.h"
+
+/* definitions of codec. don't use calculations, code may run slower. */
+
+static u8 *table_com;
+static u16 *table_dec;
+
+
+/* alaw -> ulaw */
+static u8 alaw_to_ulaw[256] =
+{
+	0xab, 0x2b, 0xe3, 0x63, 0x8b, 0x0b, 0xc9, 0x49,
+	0xba, 0x3a, 0xf6, 0x76, 0x9b, 0x1b, 0xd7, 0x57,
+	0xa3, 0x23, 0xdd, 0x5d, 0x83, 0x03, 0xc1, 0x41,
+	0xb2, 0x32, 0xeb, 0x6b, 0x93, 0x13, 0xcf, 0x4f,
+	0xaf, 0x2f, 0xe7, 0x67, 0x8f, 0x0f, 0xcd, 0x4d,
+	0xbe, 0x3e, 0xfe, 0x7e, 0x9f, 0x1f, 0xdb, 0x5b,
+	0xa7, 0x27, 0xdf, 0x5f, 0x87, 0x07, 0xc5, 0x45,
+	0xb6, 0x36, 0xef, 0x6f, 0x97, 0x17, 0xd3, 0x53,
+	0xa9, 0x29, 0xe1, 0x61, 0x89, 0x09, 0xc7, 0x47,
+	0xb8, 0x38, 0xf2, 0x72, 0x99, 0x19, 0xd5, 0x55,
+	0xa1, 0x21, 0xdc, 0x5c, 0x81, 0x01, 0xbf, 0x3f,
+	0xb0, 0x30, 0xe9, 0x69, 0x91, 0x11, 0xce, 0x4e,
+	0xad, 0x2d, 0xe5, 0x65, 0x8d, 0x0d, 0xcb, 0x4b,
+	0xbc, 0x3c, 0xfa, 0x7a, 0x9d, 0x1d, 0xd9, 0x59,
+	0xa5, 0x25, 0xde, 0x5e, 0x85, 0x05, 0xc3, 0x43,
+	0xb4, 0x34, 0xed, 0x6d, 0x95, 0x15, 0xd1, 0x51,
+	0xac, 0x2c, 0xe4, 0x64, 0x8c, 0x0c, 0xca, 0x4a,
+	0xbb, 0x3b, 0xf8, 0x78, 0x9c, 0x1c, 0xd8, 0x58,
+	0xa4, 0x24, 0xde, 0x5e, 0x84, 0x04, 0xc2, 0x42,
+	0xb3, 0x33, 0xec, 0x6c, 0x94, 0x14, 0xd0, 0x50,
+	0xb0, 0x30, 0xe8, 0x68, 0x90, 0x10, 0xce, 0x4e,
+	0xbf, 0x3f, 0xfe, 0x7e, 0xa0, 0x20, 0xdc, 0x5c,
+	0xa8, 0x28, 0xe0, 0x60, 0x88, 0x08, 0xc6, 0x46,
+	0xb7, 0x37, 0xf0, 0x70, 0x98, 0x18, 0xd4, 0x54,
+	0xaa, 0x2a, 0xe2, 0x62, 0x8a, 0x0a, 0xc8, 0x48,
+	0xb9, 0x39, 0xf4, 0x74, 0x9a, 0x1a, 0xd6, 0x56,
+	0xa2, 0x22, 0xdd, 0x5d, 0x82, 0x02, 0xc0, 0x40,
+	0xb1, 0x31, 0xea, 0x6a, 0x92, 0x12, 0xcf, 0x4f,
+	0xae, 0x2e, 0xe6, 0x66, 0x8e, 0x0e, 0xcc, 0x4c,
+	0xbd, 0x3d, 0xfc, 0x7c, 0x9e, 0x1e, 0xda, 0x5a,
+	0xa6, 0x26, 0xdf, 0x5f, 0x86, 0x06, 0xc4, 0x44,
+	0xb5, 0x35, 0xee, 0x6e, 0x96, 0x16, 0xd2, 0x52
+};
+
+/* ulaw -> alaw */
+static u8 ulaw_to_alaw[256] =
+{
+	0xab, 0x55, 0xd5, 0x15, 0x95, 0x75, 0xf5, 0x35,
+	0xb5, 0x45, 0xc5, 0x05, 0x85, 0x65, 0xe5, 0x25,
+	0xa5, 0x5d, 0xdd, 0x1d, 0x9d, 0x7d, 0xfd, 0x3d,
+	0xbd, 0x4d, 0xcd, 0x0d, 0x8d, 0x6d, 0xed, 0x2d,
+	0xad, 0x51, 0xd1, 0x11, 0x91, 0x71, 0xf1, 0x31,
+	0xb1, 0x41, 0xc1, 0x01, 0x81, 0x61, 0xe1, 0x21,
+	0x59, 0xd9, 0x19, 0x99, 0x79, 0xf9, 0x39, 0xb9,
+	0x49, 0xc9, 0x09, 0x89, 0x69, 0xe9, 0x29, 0xa9,
+	0xd7, 0x17, 0x97, 0x77, 0xf7, 0x37, 0xb7, 0x47,
+	0xc7, 0x07, 0x87, 0x67, 0xe7, 0x27, 0xa7, 0xdf,
+	0x9f, 0x7f, 0xff, 0x3f, 0xbf, 0x4f, 0xcf, 0x0f,
+	0x8f, 0x6f, 0xef, 0x2f, 0x53, 0x13, 0x73, 0x33,
+	0xb3, 0x43, 0xc3, 0x03, 0x83, 0x63, 0xe3, 0x23,
+	0xa3, 0x5b, 0xdb, 0x1b, 0x9b, 0x7b, 0xfb, 0x3b,
+	0xbb, 0xbb, 0x4b, 0x4b, 0xcb, 0xcb, 0x0b, 0x0b,
+	0x8b, 0x8b, 0x6b, 0x6b, 0xeb, 0xeb, 0x2b, 0x2b,
+	0xab, 0x54, 0xd4, 0x14, 0x94, 0x74, 0xf4, 0x34,
+	0xb4, 0x44, 0xc4, 0x04, 0x84, 0x64, 0xe4, 0x24,
+	0xa4, 0x5c, 0xdc, 0x1c, 0x9c, 0x7c, 0xfc, 0x3c,
+	0xbc, 0x4c, 0xcc, 0x0c, 0x8c, 0x6c, 0xec, 0x2c,
+	0xac, 0x50, 0xd0, 0x10, 0x90, 0x70, 0xf0, 0x30,
+	0xb0, 0x40, 0xc0, 0x00, 0x80, 0x60, 0xe0, 0x20,
+	0x58, 0xd8, 0x18, 0x98, 0x78, 0xf8, 0x38, 0xb8,
+	0x48, 0xc8, 0x08, 0x88, 0x68, 0xe8, 0x28, 0xa8,
+	0xd6, 0x16, 0x96, 0x76, 0xf6, 0x36, 0xb6, 0x46,
+	0xc6, 0x06, 0x86, 0x66, 0xe6, 0x26, 0xa6, 0xde,
+	0x9e, 0x7e, 0xfe, 0x3e, 0xbe, 0x4e, 0xce, 0x0e,
+	0x8e, 0x6e, 0xee, 0x2e, 0x52, 0x12, 0x72, 0x32,
+	0xb2, 0x42, 0xc2, 0x02, 0x82, 0x62, 0xe2, 0x22,
+	0xa2, 0x5a, 0xda, 0x1a, 0x9a, 0x7a, 0xfa, 0x3a,
+	0xba, 0xba, 0x4a, 0x4a, 0xca, 0xca, 0x0a, 0x0a,
+	0x8a, 0x8a, 0x6a, 0x6a, 0xea, 0xea, 0x2a, 0x2a
+};
+
+/* alaw -> 4bit compression */
+static u8 alaw_to_4bit[256] = {
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0d, 0x02,
+	0x0e, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x01, 0x0a, 0x05,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x08, 0x07, 0x0f, 0x00, 0x0b, 0x04,
+	0x0e, 0x01, 0x0a, 0x05, 0x0f, 0x00, 0x0c, 0x03,
+	0x0d, 0x02, 0x09, 0x06, 0x0f, 0x00, 0x0b, 0x04,
+};
+
+/* 4bit -> alaw decompression */
+static u8 _4bit_to_alaw[16] = {
+	0x5d, 0x51, 0xd9, 0xd7, 0x5f, 0x53, 0xa3, 0x4b,
+	0x2a, 0x3a, 0x22, 0x2e, 0x26, 0x56, 0x20, 0x2c,
+};
+
+/* ulaw -> 4bit compression */
+static u8 ulaw_to_4bit[256] = {
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+	0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+	0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,
+	0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,
+	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x04, 0x04,
+	0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
+	0x04, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05,
+	0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
+	0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+	0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x08,
+	0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
+	0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
+	0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
+	0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f,
+	0x0f, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e,
+	0x0e, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e, 0x0e,
+	0x0e, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d,
+	0x0d, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d, 0x0d,
+	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
+	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0b, 0x0b,
+	0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+	0x0b, 0x0b, 0x0b, 0x0b, 0x0a, 0x0a, 0x0a, 0x0a,
+	0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a,
+	0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09,
+	0x09, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+};
+
+/* 4bit -> ulaw decompression */
+static u8 _4bit_to_ulaw[16] = {
+	0x11, 0x21, 0x31, 0x40, 0x4e, 0x5c, 0x68, 0x71,
+	0xfe, 0xef, 0xe7, 0xdb, 0xcd, 0xbf, 0xaf, 0x9f,
+};
+
+
+/*
+ * Compresses data to the result buffer
+ * The result size must be at least half of the input buffer.
+ * The number of samples also must be even!
+ */
+int
+l1oip_law_to_4bit(u8 *data, int len, u8 *result, u32 *state)
+{
+	int ii, i = 0, o = 0;
+
+	if (!len)
+		return 0;
+
+	/* send saved byte and first input byte */
+	if (*state) {
+		*result++ = table_com[(((*state) << 8) & 0xff00) | (*data++)];
+		len--;
+		o++;
+	}
+
+	ii = len >> 1;
+
+	while (i < ii) {
+		*result++ = table_com[(data[0]<<8) | (data[1])];
+		data += 2;
+		i++;
+		o++;
+	}
+
+	/* if len has an odd number, we save byte for next call */
+	if (len & 1)
+		*state = 0x100 + *data;
+	else
+		*state = 0;
+
+	return o;
+}
+
+/* Decompress data to the result buffer
+ * The result size must be the number of sample in packet. (2 * input data)
+ * The number of samples in the result are even!
+ */
+int
+l1oip_4bit_to_law(u8 *data, int len, u8 *result)
+{
+	int i = 0;
+	u16 r;
+
+	while (i < len) {
+		r = table_dec[*data++];
+		*result++ = r >> 8;
+		*result++ = r;
+		i++;
+	}
+
+	return len << 1;
+}
+
+
+/*
+ * law conversion
+ */
+int
+l1oip_alaw_to_ulaw(u8 *data, int len, u8 *result)
+{
+	int i = 0;
+
+	while (i < len) {
+		*result++ = alaw_to_ulaw[*data++];
+		i++;
+	}
+
+	return len;
+}
+
+int
+l1oip_ulaw_to_alaw(u8 *data, int len, u8 *result)
+{
+	int i = 0;
+
+	while (i < len) {
+		*result++ = ulaw_to_alaw[*data++];
+		i++;
+	}
+
+	return len;
+}
+
+
+/*
+ * generate/free compression and decompression table
+ */
+void
+l1oip_4bit_free(void)
+{
+	vfree(table_dec);
+	vfree(table_com);
+	table_com = NULL;
+	table_dec = NULL;
+}
+
+int
+l1oip_4bit_alloc(int ulaw)
+{
+	int i1, i2, c, sample;
+
+	/* in case, it is called again */
+	if (table_dec)
+		return 0;
+
+	/* alloc conversion tables */
+	table_com = vzalloc(65536);
+	table_dec = vzalloc(512);
+	if (!table_com || !table_dec) {
+		l1oip_4bit_free();
+		return -ENOMEM;
+	}
+	/* generate compression table */
+	i1 = 0;
+	while (i1 < 256) {
+		if (ulaw)
+			c = ulaw_to_4bit[i1];
+		else
+			c = alaw_to_4bit[i1];
+		i2 = 0;
+		while (i2 < 256) {
+			table_com[(i1 << 8) | i2] |= (c << 4);
+			table_com[(i2 << 8) | i1] |= c;
+			i2++;
+		}
+		i1++;
+	}
+
+	/* generate decompression table */
+	i1 = 0;
+	while (i1 < 16) {
+		if (ulaw)
+			sample = _4bit_to_ulaw[i1];
+		else
+			sample = _4bit_to_alaw[i1];
+		i2 = 0;
+		while (i2 < 16) {
+			table_dec[(i1 << 4) | i2] |= (sample << 8);
+			table_dec[(i2 << 4) | i1] |= sample;
+			i2++;
+		}
+		i1++;
+	}
+
+	return 0;
+}
diff --git a/drivers/isdn/mISDN/l1oip_core.c b/drivers/isdn/mISDN/l1oip_core.c
new file mode 100644
index 000000000..c24771336
--- /dev/null
+++ b/drivers/isdn/mISDN/l1oip_core.c
@@ -0,0 +1,1504 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+
+ * l1oip.c  low level driver for tunneling layer 1 over IP
+ *
+ * NOTE: It is not compatible with TDMoIP nor "ISDN over IP".
+ *
+ * Author	Andreas Eversberg (jolly@eversberg.eu)
+ */
+
+/* module parameters:
+ * type:
+ Value 1	= BRI
+ Value 2	= PRI
+ Value 3 = BRI (multi channel frame, not supported yet)
+ Value 4 = PRI (multi channel frame, not supported yet)
+ A multi channel frame reduces overhead to a single frame for all
+ b-channels, but increases delay.
+ (NOTE: Multi channel frames are not implemented yet.)
+
+ * codec:
+ Value 0 = transparent (default)
+ Value 1 = transfer ALAW
+ Value 2 = transfer ULAW
+ Value 3 = transfer generic 4 bit compression.
+
+ * ulaw:
+ 0 = we use a-Law (default)
+ 1 = we use u-Law
+
+ * limit:
+ limitation of B-channels to control bandwidth (1...126)
+ BRI: 1 or 2
+ PRI: 1-30, 31-126 (126, because dchannel ist not counted here)
+ Also limited ressources are used for stack, resulting in less channels.
+ It is possible to have more channels than 30 in PRI mode, this must
+ be supported by the application.
+
+ * ip:
+ byte representation of remote ip address (127.0.0.1 -> 127,0,0,1)
+ If not given or four 0, no remote address is set.
+ For multiple interfaces, concat ip addresses. (127,0,0,1,127,0,0,1)
+
+ * port:
+ port number (local interface)
+ If not given or 0, port 931 is used for fist instance, 932 for next...
+ For multiple interfaces, different ports must be given.
+
+ * remoteport:
+ port number (remote interface)
+ If not given or 0, remote port equals local port
+ For multiple interfaces on equal sites, different ports must be given.
+
+ * ondemand:
+ 0 = fixed (always transmit packets, even when remote side timed out)
+ 1 = on demand (only transmit packets, when remote side is detected)
+ the default is 0
+ NOTE: ID must also be set for on demand.
+
+ * id:
+ optional value to identify frames. This value must be equal on both
+ peers and should be random. If omitted or 0, no ID is transmitted.
+
+ * debug:
+ NOTE: only one debug value must be given for all cards
+ enable debugging (see l1oip.h for debug options)
+
+
+ Special mISDN controls:
+
+ op = MISDN_CTRL_SETPEER*
+ p1 = bytes 0-3 : remote IP address in network order (left element first)
+ p2 = bytes 1-2 : remote port in network order (high byte first)
+ optional:
+ p2 = bytes 3-4 : local port in network order (high byte first)
+
+ op = MISDN_CTRL_UNSETPEER*
+
+ * Use l1oipctrl for comfortable setting or removing ip address.
+ (Layer 1 Over IP CTRL)
+
+
+ L1oIP-Protocol
+ --------------
+
+ Frame Header:
+
+ 7 6 5 4 3 2 1 0
+ +---------------+
+ |Ver|T|I|Coding |
+ +---------------+
+ |  ID byte 3 *  |
+ +---------------+
+ |  ID byte 2 *  |
+ +---------------+
+ |  ID byte 1 *  |
+ +---------------+
+ |  ID byte 0 *  |
+ +---------------+
+ |M|   Channel   |
+ +---------------+
+ |    Length *   |
+ +---------------+
+ | Time Base MSB |
+ +---------------+
+ | Time Base LSB |
+ +---------------+
+ | Data....	|
+
+ ...
+
+ |               |
+ +---------------+
+ |M|   Channel   |
+ +---------------+
+ |    Length *   |
+ +---------------+
+ | Time Base MSB |
+ +---------------+
+ | Time Base LSB |
+ +---------------+
+ | Data....	|
+
+ ...
+
+
+ * Only included in some cases.
+
+ - Ver = Version
+ If version is missmatch, the frame must be ignored.
+
+ - T = Type of interface
+ Must be 0 for S0 or 1 for E1.
+
+ - I = Id present
+ If bit is set, four ID bytes are included in frame.
+
+ - ID = Connection ID
+ Additional ID to prevent Denial of Service attacs. Also it prevents hijacking
+ connections with dynamic IP. The ID should be random and must not be 0.
+
+ - Coding = Type of codec
+ Must be 0 for no transcoding. Also for D-channel and other HDLC frames.
+ 1 and 2 are reserved for explicitly use of a-LAW or u-LAW codec.
+ 3 is used for generic table compressor.
+
+ - M = More channels to come. If this flag is 1, the following byte contains
+ the length of the channel data. After the data block, the next channel will
+ be defined. The flag for the last channel block (or if only one channel is
+ transmitted), must be 0 and no length is given.
+
+ - Channel = Channel number
+ 0 reserved
+ 1-3 channel data for S0 (3 is D-channel)
+ 1-31 channel data for E1 (16 is D-channel)
+ 32-127 channel data for extended E1 (16 is D-channel)
+
+ - The length is used if the M-flag is 1. It is used to find the next channel
+ inside frame.
+ NOTE: A value of 0 equals 256 bytes of data.
+ -> For larger data blocks, a single frame must be used.
+ -> For larger streams, a single frame or multiple blocks with same channel ID
+ must be used.
+
+ - Time Base = Timestamp of first sample in frame
+ The "Time Base" is used to rearange packets and to detect packet loss.
+ The 16 bits are sent in network order (MSB first) and count 1/8000 th of a
+ second. This causes a wrap around each 8,192 seconds. There is no requirement
+ for the initial "Time Base", but 0 should be used for the first packet.
+ In case of HDLC data, this timestamp counts the packet or byte number.
+
+
+ Two Timers:
+
+ After initialisation, a timer of 15 seconds is started. Whenever a packet is
+ transmitted, the timer is reset to 15 seconds again. If the timer expires, an
+ empty packet is transmitted. This keep the connection alive.
+
+ When a valid packet is received, a timer 65 seconds is started. The interface
+ become ACTIVE. If the timer expires, the interface becomes INACTIVE.
+
+
+ Dynamic IP handling:
+
+ To allow dynamic IP, the ID must be non 0. In this case, any packet with the
+ correct port number and ID will be accepted. If the remote side changes its IP
+ the new IP is used for all transmitted packets until it changes again.
+
+
+ On Demand:
+
+ If the ondemand parameter is given, the remote IP is set to 0 on timeout.
+ This will stop keepalive traffic to remote. If the remote is online again,
+ traffic will continue to the remote address. This is useful for road warriors.
+ This feature only works with ID set, otherwhise it is highly unsecure.
+
+
+ Socket and Thread
+ -----------------
+
+ The complete socket opening and closing is done by a thread.
+ When the thread opened a socket, the hc->socket descriptor is set. Whenever a
+ packet shall be sent to the socket, the hc->socket must be checked whether not
+ NULL. To prevent change in socket descriptor, the hc->socket_lock must be used.
+ To change the socket, a recall of l1oip_socket_open() will safely kill the
+ socket process and create a new one.
+
+*/
+
+#define L1OIP_VERSION	0	/* 0...3 */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNhw.h>
+#include <linux/mISDNdsp.h>
+#include <linux/init.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <linux/sched/signal.h>
+
+#include <net/sock.h>
+#include "core.h"
+#include "l1oip.h"
+
+static const char *l1oip_revision = "2.00";
+
+static int l1oip_cnt;
+static DEFINE_SPINLOCK(l1oip_lock);
+static LIST_HEAD(l1oip_ilist);
+
+#define MAX_CARDS	16
+static u_int type[MAX_CARDS];
+static u_int codec[MAX_CARDS];
+static u_int ip[MAX_CARDS * 4];
+static u_int port[MAX_CARDS];
+static u_int remoteport[MAX_CARDS];
+static u_int ondemand[MAX_CARDS];
+static u_int limit[MAX_CARDS];
+static u_int id[MAX_CARDS];
+static int debug;
+static int ulaw;
+
+MODULE_AUTHOR("Andreas Eversberg");
+MODULE_LICENSE("GPL");
+module_param_array(type, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(codec, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(ip, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(port, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(remoteport, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(ondemand, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(limit, uint, NULL, S_IRUGO | S_IWUSR);
+module_param_array(id, uint, NULL, S_IRUGO | S_IWUSR);
+module_param(ulaw, uint, S_IRUGO | S_IWUSR);
+module_param(debug, uint, S_IRUGO | S_IWUSR);
+
+/*
+ * send a frame via socket, if open and restart timer
+ */
+static int
+l1oip_socket_send(struct l1oip *hc, u8 localcodec, u8 channel, u32 chanmask,
+		  u16 timebase, u8 *buf, int len)
+{
+	u8 *p;
+	u8 frame[MAX_DFRAME_LEN_L1 + 32];
+	struct socket *socket = NULL;
+
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: sending data to socket (len = %d)\n",
+		       __func__, len);
+
+	p = frame;
+
+	/* restart timer */
+	if (time_before(hc->keep_tl.expires, jiffies + 5 * HZ) && !hc->shutdown)
+		mod_timer(&hc->keep_tl, jiffies + L1OIP_KEEPALIVE * HZ);
+	else
+		hc->keep_tl.expires = jiffies + L1OIP_KEEPALIVE * HZ;
+
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: resetting timer\n", __func__);
+
+	/* drop if we have no remote ip or port */
+	if (!hc->sin_remote.sin_addr.s_addr || !hc->sin_remote.sin_port) {
+		if (debug & DEBUG_L1OIP_MSG)
+			printk(KERN_DEBUG "%s: dropping frame, because remote "
+			       "IP is not set.\n", __func__);
+		return len;
+	}
+
+	/* assemble frame */
+	*p++ = (L1OIP_VERSION << 6) /* version and coding */
+		| (hc->pri ? 0x20 : 0x00) /* type */
+		| (hc->id ? 0x10 : 0x00) /* id */
+		| localcodec;
+	if (hc->id) {
+		*p++ = hc->id >> 24; /* id */
+		*p++ = hc->id >> 16;
+		*p++ = hc->id >> 8;
+		*p++ = hc->id;
+	}
+	*p++ =  0x00 + channel; /* m-flag, channel */
+	*p++ = timebase >> 8; /* time base */
+	*p++ = timebase;
+
+	if (buf && len) { /* add data to frame */
+		if (localcodec == 1 && ulaw)
+			l1oip_ulaw_to_alaw(buf, len, p);
+		else if (localcodec == 2 && !ulaw)
+			l1oip_alaw_to_ulaw(buf, len, p);
+		else if (localcodec == 3)
+			len = l1oip_law_to_4bit(buf, len, p,
+						&hc->chan[channel].codecstate);
+		else
+			memcpy(p, buf, len);
+	}
+	len += p - frame;
+
+	/* check for socket in safe condition */
+	spin_lock(&hc->socket_lock);
+	if (!hc->socket) {
+		spin_unlock(&hc->socket_lock);
+		return 0;
+	}
+	/* seize socket */
+	socket = hc->socket;
+	hc->socket = NULL;
+	spin_unlock(&hc->socket_lock);
+	/* send packet */
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: sending packet to socket (len "
+		       "= %d)\n", __func__, len);
+	hc->sendiov.iov_base = frame;
+	hc->sendiov.iov_len  = len;
+	len = kernel_sendmsg(socket, &hc->sendmsg, &hc->sendiov, 1, len);
+	/* give socket back */
+	hc->socket = socket; /* no locking required */
+
+	return len;
+}
+
+
+/*
+ * receive channel data from socket
+ */
+static void
+l1oip_socket_recv(struct l1oip *hc, u8 remotecodec, u8 channel, u16 timebase,
+		  u8 *buf, int len)
+{
+	struct sk_buff *nskb;
+	struct bchannel *bch;
+	struct dchannel *dch;
+	u8 *p;
+	u32 rx_counter;
+
+	if (len == 0) {
+		if (debug & DEBUG_L1OIP_MSG)
+			printk(KERN_DEBUG "%s: received empty keepalive data, "
+			       "ignoring\n", __func__);
+		return;
+	}
+
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: received data, sending to mISDN (%d)\n",
+		       __func__, len);
+
+	if (channel < 1 || channel > 127) {
+		printk(KERN_WARNING "%s: packet error - channel %d out of "
+		       "range\n", __func__, channel);
+		return;
+	}
+	dch = hc->chan[channel].dch;
+	bch = hc->chan[channel].bch;
+	if (!dch && !bch) {
+		printk(KERN_WARNING "%s: packet error - channel %d not in "
+		       "stack\n", __func__, channel);
+		return;
+	}
+
+	/* prepare message */
+	nskb = mI_alloc_skb((remotecodec == 3) ? (len << 1) : len, GFP_ATOMIC);
+	if (!nskb) {
+		printk(KERN_ERR "%s: No mem for skb.\n", __func__);
+		return;
+	}
+	p = skb_put(nskb, (remotecodec == 3) ? (len << 1) : len);
+
+	if (remotecodec == 1 && ulaw)
+		l1oip_alaw_to_ulaw(buf, len, p);
+	else if (remotecodec == 2 && !ulaw)
+		l1oip_ulaw_to_alaw(buf, len, p);
+	else if (remotecodec == 3)
+		len = l1oip_4bit_to_law(buf, len, p);
+	else
+		memcpy(p, buf, len);
+
+	/* send message up */
+	if (dch && len >= 2) {
+		dch->rx_skb = nskb;
+		recv_Dchannel(dch);
+	}
+	if (bch) {
+		/* expand 16 bit sequence number to 32 bit sequence number */
+		rx_counter = hc->chan[channel].rx_counter;
+		if (((s16)(timebase - rx_counter)) >= 0) {
+			/* time has changed forward */
+			if (timebase >= (rx_counter & 0xffff))
+				rx_counter =
+					(rx_counter & 0xffff0000) | timebase;
+			else
+				rx_counter = ((rx_counter & 0xffff0000) + 0x10000)
+					| timebase;
+		} else {
+			/* time has changed backwards */
+			if (timebase < (rx_counter & 0xffff))
+				rx_counter =
+					(rx_counter & 0xffff0000) | timebase;
+			else
+				rx_counter = ((rx_counter & 0xffff0000) - 0x10000)
+					| timebase;
+		}
+		hc->chan[channel].rx_counter = rx_counter;
+
+#ifdef REORDER_DEBUG
+		if (hc->chan[channel].disorder_flag) {
+			swap(hc->chan[channel].disorder_skb, nskb);
+			swap(hc->chan[channel].disorder_cnt, rx_counter);
+		}
+		hc->chan[channel].disorder_flag ^= 1;
+		if (nskb)
+#endif
+			queue_ch_frame(&bch->ch, PH_DATA_IND, rx_counter, nskb);
+	}
+}
+
+
+/*
+ * parse frame and extract channel data
+ */
+static void
+l1oip_socket_parse(struct l1oip *hc, struct sockaddr_in *sin, u8 *buf, int len)
+{
+	u32			packet_id;
+	u8			channel;
+	u8			remotecodec;
+	u16			timebase;
+	int			m, mlen;
+	int			len_start = len; /* initial frame length */
+	struct dchannel		*dch = hc->chan[hc->d_idx].dch;
+
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: received frame, parsing... (%d)\n",
+		       __func__, len);
+
+	/* check length */
+	if (len < 1 + 1 + 2) {
+		printk(KERN_WARNING "%s: packet error - length %d below "
+		       "4 bytes\n", __func__, len);
+		return;
+	}
+
+	/* check version */
+	if (((*buf) >> 6) != L1OIP_VERSION) {
+		printk(KERN_WARNING "%s: packet error - unknown version %d\n",
+		       __func__, buf[0]>>6);
+		return;
+	}
+
+	/* check type */
+	if (((*buf) & 0x20) && !hc->pri) {
+		printk(KERN_WARNING "%s: packet error - received E1 packet "
+		       "on S0 interface\n", __func__);
+		return;
+	}
+	if (!((*buf) & 0x20) && hc->pri) {
+		printk(KERN_WARNING "%s: packet error - received S0 packet "
+		       "on E1 interface\n", __func__);
+		return;
+	}
+
+	/* get id flag */
+	packet_id = (*buf >> 4) & 1;
+
+	/* check coding */
+	remotecodec = (*buf) & 0x0f;
+	if (remotecodec > 3) {
+		printk(KERN_WARNING "%s: packet error - remotecodec %d "
+		       "unsupported\n", __func__, remotecodec);
+		return;
+	}
+	buf++;
+	len--;
+
+	/* check packet_id */
+	if (packet_id) {
+		if (!hc->id) {
+			printk(KERN_WARNING "%s: packet error - packet has id "
+			       "0x%x, but we have not\n", __func__, packet_id);
+			return;
+		}
+		if (len < 4) {
+			printk(KERN_WARNING "%s: packet error - packet too "
+			       "short for ID value\n", __func__);
+			return;
+		}
+		packet_id = (*buf++) << 24;
+		packet_id += (*buf++) << 16;
+		packet_id += (*buf++) << 8;
+		packet_id += (*buf++);
+		len -= 4;
+
+		if (packet_id != hc->id) {
+			printk(KERN_WARNING "%s: packet error - ID mismatch, "
+			       "got 0x%x, we 0x%x\n",
+			       __func__, packet_id, hc->id);
+			return;
+		}
+	} else {
+		if (hc->id) {
+			printk(KERN_WARNING "%s: packet error - packet has no "
+			       "ID, but we have\n", __func__);
+			return;
+		}
+	}
+
+multiframe:
+	if (len < 1) {
+		printk(KERN_WARNING "%s: packet error - packet too short, "
+		       "channel expected at position %d.\n",
+		       __func__, len-len_start + 1);
+		return;
+	}
+
+	/* get channel and multiframe flag */
+	channel = *buf & 0x7f;
+	m = *buf >> 7;
+	buf++;
+	len--;
+
+	/* check length on multiframe */
+	if (m) {
+		if (len < 1) {
+			printk(KERN_WARNING "%s: packet error - packet too "
+			       "short, length expected at position %d.\n",
+			       __func__, len_start - len - 1);
+			return;
+		}
+
+		mlen = *buf++;
+		len--;
+		if (mlen == 0)
+			mlen = 256;
+		if (len < mlen + 3) {
+			printk(KERN_WARNING "%s: packet error - length %d at "
+			       "position %d exceeds total length %d.\n",
+			       __func__, mlen, len_start-len - 1, len_start);
+			return;
+		}
+		if (len == mlen + 3) {
+			printk(KERN_WARNING "%s: packet error - length %d at "
+			       "position %d will not allow additional "
+			       "packet.\n",
+			       __func__, mlen, len_start-len + 1);
+			return;
+		}
+	} else
+		mlen = len - 2; /* single frame, subtract timebase */
+
+	if (len < 2) {
+		printk(KERN_WARNING "%s: packet error - packet too short, time "
+		       "base expected at position %d.\n",
+		       __func__, len-len_start + 1);
+		return;
+	}
+
+	/* get time base */
+	timebase = (*buf++) << 8;
+	timebase |= (*buf++);
+	len -= 2;
+
+	/* if inactive, we send up a PH_ACTIVATE and activate */
+	if (!test_bit(FLG_ACTIVE, &dch->Flags)) {
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: interface become active due to "
+			       "received packet\n", __func__);
+		test_and_set_bit(FLG_ACTIVE, &dch->Flags);
+		_queue_data(&dch->dev.D, PH_ACTIVATE_IND, MISDN_ID_ANY, 0,
+			    NULL, GFP_ATOMIC);
+	}
+
+	/* distribute packet */
+	l1oip_socket_recv(hc, remotecodec, channel, timebase, buf, mlen);
+	buf += mlen;
+	len -= mlen;
+
+	/* multiframe */
+	if (m)
+		goto multiframe;
+
+	/* restart timer */
+	if ((time_before(hc->timeout_tl.expires, jiffies + 5 * HZ) ||
+	     !hc->timeout_on) &&
+	    !hc->shutdown) {
+		hc->timeout_on = 1;
+		mod_timer(&hc->timeout_tl, jiffies + L1OIP_TIMEOUT * HZ);
+	} else /* only adjust timer */
+		hc->timeout_tl.expires = jiffies + L1OIP_TIMEOUT * HZ;
+
+	/* if ip or source port changes */
+	if ((hc->sin_remote.sin_addr.s_addr != sin->sin_addr.s_addr)
+	    || (hc->sin_remote.sin_port != sin->sin_port)) {
+		if (debug & DEBUG_L1OIP_SOCKET)
+			printk(KERN_DEBUG "%s: remote address changes from "
+			       "0x%08x to 0x%08x (port %d to %d)\n", __func__,
+			       ntohl(hc->sin_remote.sin_addr.s_addr),
+			       ntohl(sin->sin_addr.s_addr),
+			       ntohs(hc->sin_remote.sin_port),
+			       ntohs(sin->sin_port));
+		hc->sin_remote.sin_addr.s_addr = sin->sin_addr.s_addr;
+		hc->sin_remote.sin_port = sin->sin_port;
+	}
+}
+
+
+/*
+ * socket stuff
+ */
+static int
+l1oip_socket_thread(void *data)
+{
+	struct l1oip *hc = (struct l1oip *)data;
+	int ret = 0;
+	struct sockaddr_in sin_rx;
+	struct kvec iov;
+	struct msghdr msg = {.msg_name = &sin_rx,
+			     .msg_namelen = sizeof(sin_rx)};
+	unsigned char *recvbuf;
+	size_t recvbuf_size = 1500;
+	int recvlen;
+	struct socket *socket = NULL;
+	DECLARE_COMPLETION_ONSTACK(wait);
+
+	/* allocate buffer memory */
+	recvbuf = kmalloc(recvbuf_size, GFP_KERNEL);
+	if (!recvbuf) {
+		printk(KERN_ERR "%s: Failed to alloc recvbuf.\n", __func__);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	iov.iov_base = recvbuf;
+	iov.iov_len = recvbuf_size;
+
+	/* make daemon */
+	allow_signal(SIGTERM);
+
+	/* create socket */
+	if (sock_create(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &socket)) {
+		printk(KERN_ERR "%s: Failed to create socket.\n", __func__);
+		ret = -EIO;
+		goto fail;
+	}
+
+	/* set incoming address */
+	hc->sin_local.sin_family = AF_INET;
+	hc->sin_local.sin_addr.s_addr = INADDR_ANY;
+	hc->sin_local.sin_port = htons((unsigned short)hc->localport);
+
+	/* set outgoing address */
+	hc->sin_remote.sin_family = AF_INET;
+	hc->sin_remote.sin_addr.s_addr = htonl(hc->remoteip);
+	hc->sin_remote.sin_port = htons((unsigned short)hc->remoteport);
+
+	/* bind to incoming port */
+	if (socket->ops->bind(socket, (struct sockaddr *)&hc->sin_local,
+			      sizeof(hc->sin_local))) {
+		printk(KERN_ERR "%s: Failed to bind socket to port %d.\n",
+		       __func__, hc->localport);
+		ret = -EINVAL;
+		goto fail;
+	}
+
+	/* check sk */
+	if (socket->sk == NULL) {
+		printk(KERN_ERR "%s: socket->sk == NULL\n", __func__);
+		ret = -EIO;
+		goto fail;
+	}
+
+	/* build send message */
+	hc->sendmsg.msg_name = &hc->sin_remote;
+	hc->sendmsg.msg_namelen = sizeof(hc->sin_remote);
+	hc->sendmsg.msg_control = NULL;
+	hc->sendmsg.msg_controllen = 0;
+
+	/* give away socket */
+	spin_lock(&hc->socket_lock);
+	hc->socket = socket;
+	spin_unlock(&hc->socket_lock);
+
+	/* read loop */
+	if (debug & DEBUG_L1OIP_SOCKET)
+		printk(KERN_DEBUG "%s: socket created and open\n",
+		       __func__);
+	while (!signal_pending(current)) {
+		iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, recvbuf_size);
+		recvlen = sock_recvmsg(socket, &msg, 0);
+		if (recvlen > 0) {
+			l1oip_socket_parse(hc, &sin_rx, recvbuf, recvlen);
+		} else {
+			if (debug & DEBUG_L1OIP_SOCKET)
+				printk(KERN_WARNING
+				       "%s: broken pipe on socket\n", __func__);
+		}
+	}
+
+	/* get socket back, check first if in use, maybe by send function */
+	spin_lock(&hc->socket_lock);
+	/* if hc->socket is NULL, it is in use until it is given back */
+	while (!hc->socket) {
+		spin_unlock(&hc->socket_lock);
+		schedule_timeout(HZ / 10);
+		spin_lock(&hc->socket_lock);
+	}
+	hc->socket = NULL;
+	spin_unlock(&hc->socket_lock);
+
+	if (debug & DEBUG_L1OIP_SOCKET)
+		printk(KERN_DEBUG "%s: socket thread terminating\n",
+		       __func__);
+
+fail:
+	/* free recvbuf */
+	kfree(recvbuf);
+
+	/* close socket */
+	if (socket)
+		sock_release(socket);
+
+	/* if we got killed, signal completion */
+	complete(&hc->socket_complete);
+	hc->socket_thread = NULL; /* show termination of thread */
+
+	if (debug & DEBUG_L1OIP_SOCKET)
+		printk(KERN_DEBUG "%s: socket thread terminated\n",
+		       __func__);
+	return ret;
+}
+
+static void
+l1oip_socket_close(struct l1oip *hc)
+{
+	struct dchannel *dch = hc->chan[hc->d_idx].dch;
+
+	/* kill thread */
+	if (hc->socket_thread) {
+		if (debug & DEBUG_L1OIP_SOCKET)
+			printk(KERN_DEBUG "%s: socket thread exists, "
+			       "killing...\n", __func__);
+		send_sig(SIGTERM, hc->socket_thread, 0);
+		wait_for_completion(&hc->socket_complete);
+	}
+
+	/* if active, we send up a PH_DEACTIVATE and deactivate */
+	if (test_bit(FLG_ACTIVE, &dch->Flags)) {
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: interface become deactivated "
+			       "due to timeout\n", __func__);
+		test_and_clear_bit(FLG_ACTIVE, &dch->Flags);
+		_queue_data(&dch->dev.D, PH_DEACTIVATE_IND, MISDN_ID_ANY, 0,
+			    NULL, GFP_ATOMIC);
+	}
+}
+
+static int
+l1oip_socket_open(struct l1oip *hc)
+{
+	/* in case of reopen, we need to close first */
+	l1oip_socket_close(hc);
+
+	init_completion(&hc->socket_complete);
+
+	/* create receive process */
+	hc->socket_thread = kthread_run(l1oip_socket_thread, hc, "l1oip_%s",
+					hc->name);
+	if (IS_ERR(hc->socket_thread)) {
+		int err = PTR_ERR(hc->socket_thread);
+		printk(KERN_ERR "%s: Failed (%d) to create socket process.\n",
+		       __func__, err);
+		hc->socket_thread = NULL;
+		sock_release(hc->socket);
+		return err;
+	}
+	if (debug & DEBUG_L1OIP_SOCKET)
+		printk(KERN_DEBUG "%s: socket thread created\n", __func__);
+
+	return 0;
+}
+
+
+static void
+l1oip_send_bh(struct work_struct *work)
+{
+	struct l1oip *hc = container_of(work, struct l1oip, workq);
+
+	if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+		printk(KERN_DEBUG "%s: keepalive timer expired, sending empty "
+		       "frame on dchannel\n", __func__);
+
+	/* send an empty l1oip frame at D-channel */
+	l1oip_socket_send(hc, 0, hc->d_idx, 0, 0, NULL, 0);
+}
+
+
+/*
+ * timer stuff
+ */
+static void
+l1oip_keepalive(struct timer_list *t)
+{
+	struct l1oip *hc = from_timer(hc, t, keep_tl);
+
+	schedule_work(&hc->workq);
+}
+
+static void
+l1oip_timeout(struct timer_list *t)
+{
+	struct l1oip			*hc = from_timer(hc, t,
+								  timeout_tl);
+	struct dchannel		*dch = hc->chan[hc->d_idx].dch;
+
+	if (debug & DEBUG_L1OIP_MSG)
+		printk(KERN_DEBUG "%s: timeout timer expired, turn layer one "
+		       "down.\n", __func__);
+
+	hc->timeout_on = 0; /* state that timer must be initialized next time */
+
+	/* if timeout, we send up a PH_DEACTIVATE and deactivate */
+	if (test_bit(FLG_ACTIVE, &dch->Flags)) {
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: interface become deactivated "
+			       "due to timeout\n", __func__);
+		test_and_clear_bit(FLG_ACTIVE, &dch->Flags);
+		_queue_data(&dch->dev.D, PH_DEACTIVATE_IND, MISDN_ID_ANY, 0,
+			    NULL, GFP_ATOMIC);
+	}
+
+	/* if we have ondemand set, we remove ip address */
+	if (hc->ondemand) {
+		if (debug & DEBUG_L1OIP_MSG)
+			printk(KERN_DEBUG "%s: on demand causes ip address to "
+			       "be removed\n", __func__);
+		hc->sin_remote.sin_addr.s_addr = 0;
+	}
+}
+
+
+/*
+ * message handling
+ */
+static int
+handle_dmsg(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct mISDNdevice	*dev = container_of(ch, struct mISDNdevice, D);
+	struct dchannel		*dch = container_of(dev, struct dchannel, dev);
+	struct l1oip			*hc = dch->hw;
+	struct mISDNhead	*hh = mISDN_HEAD_P(skb);
+	int			ret = -EINVAL;
+	int			l, ll;
+	unsigned char		*p;
+
+	switch (hh->prim) {
+	case PH_DATA_REQ:
+		if (skb->len < 1) {
+			printk(KERN_WARNING "%s: skb too small\n",
+			       __func__);
+			break;
+		}
+		if (skb->len > MAX_DFRAME_LEN_L1 || skb->len > L1OIP_MAX_LEN) {
+			printk(KERN_WARNING "%s: skb too large\n",
+			       __func__);
+			break;
+		}
+		/* send frame */
+		p = skb->data;
+		l = skb->len;
+		while (l) {
+			/*
+			 * This is technically bounded by L1OIP_MAX_PERFRAME but
+			 * MAX_DFRAME_LEN_L1 < L1OIP_MAX_PERFRAME
+			 */
+			ll = (l < MAX_DFRAME_LEN_L1) ? l : MAX_DFRAME_LEN_L1;
+			l1oip_socket_send(hc, 0, dch->slot, 0,
+					  hc->chan[dch->slot].tx_counter++, p, ll);
+			p += ll;
+			l -= ll;
+		}
+		skb_trim(skb, 0);
+		queue_ch_frame(ch, PH_DATA_CNF, hh->id, skb);
+		return 0;
+	case PH_ACTIVATE_REQ:
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: PH_ACTIVATE channel %d (1..%d)\n"
+			       , __func__, dch->slot, hc->b_num + 1);
+		skb_trim(skb, 0);
+		if (test_bit(FLG_ACTIVE, &dch->Flags))
+			queue_ch_frame(ch, PH_ACTIVATE_IND, hh->id, skb);
+		else
+			queue_ch_frame(ch, PH_DEACTIVATE_IND, hh->id, skb);
+		return 0;
+	case PH_DEACTIVATE_REQ:
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: PH_DEACTIVATE channel %d "
+			       "(1..%d)\n", __func__, dch->slot,
+			       hc->b_num + 1);
+		skb_trim(skb, 0);
+		if (test_bit(FLG_ACTIVE, &dch->Flags))
+			queue_ch_frame(ch, PH_ACTIVATE_IND, hh->id, skb);
+		else
+			queue_ch_frame(ch, PH_DEACTIVATE_IND, hh->id, skb);
+		return 0;
+	}
+	if (!ret)
+		dev_kfree_skb(skb);
+	return ret;
+}
+
+static int
+channel_dctrl(struct dchannel *dch, struct mISDN_ctrl_req *cq)
+{
+	int	ret = 0;
+	struct l1oip	*hc = dch->hw;
+
+	switch (cq->op) {
+	case MISDN_CTRL_GETOP:
+		cq->op = MISDN_CTRL_SETPEER | MISDN_CTRL_UNSETPEER
+			| MISDN_CTRL_GETPEER;
+		break;
+	case MISDN_CTRL_SETPEER:
+		hc->remoteip = (u32)cq->p1;
+		hc->remoteport = cq->p2 & 0xffff;
+		hc->localport = cq->p2 >> 16;
+		if (!hc->remoteport)
+			hc->remoteport = hc->localport;
+		if (debug & DEBUG_L1OIP_SOCKET)
+			printk(KERN_DEBUG "%s: got new ip address from user "
+			       "space.\n", __func__);
+		l1oip_socket_open(hc);
+		break;
+	case MISDN_CTRL_UNSETPEER:
+		if (debug & DEBUG_L1OIP_SOCKET)
+			printk(KERN_DEBUG "%s: removing ip address.\n",
+			       __func__);
+		hc->remoteip = 0;
+		l1oip_socket_open(hc);
+		break;
+	case MISDN_CTRL_GETPEER:
+		if (debug & DEBUG_L1OIP_SOCKET)
+			printk(KERN_DEBUG "%s: getting ip address.\n",
+			       __func__);
+		cq->p1 = hc->remoteip;
+		cq->p2 = hc->remoteport | (hc->localport << 16);
+		break;
+	default:
+		printk(KERN_WARNING "%s: unknown Op %x\n",
+		       __func__, cq->op);
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int
+open_dchannel(struct l1oip *hc, struct dchannel *dch, struct channel_req *rq)
+{
+	if (debug & DEBUG_HW_OPEN)
+		printk(KERN_DEBUG "%s: dev(%d) open from %p\n", __func__,
+		       dch->dev.id, __builtin_return_address(0));
+	if (rq->protocol == ISDN_P_NONE)
+		return -EINVAL;
+	if ((dch->dev.D.protocol != ISDN_P_NONE) &&
+	    (dch->dev.D.protocol != rq->protocol)) {
+		if (debug & DEBUG_HW_OPEN)
+			printk(KERN_WARNING "%s: change protocol %x to %x\n",
+			       __func__, dch->dev.D.protocol, rq->protocol);
+	}
+	if (dch->dev.D.protocol != rq->protocol)
+		dch->dev.D.protocol = rq->protocol;
+
+	if (test_bit(FLG_ACTIVE, &dch->Flags)) {
+		_queue_data(&dch->dev.D, PH_ACTIVATE_IND, MISDN_ID_ANY,
+			    0, NULL, GFP_KERNEL);
+	}
+	rq->ch = &dch->dev.D;
+	if (!try_module_get(THIS_MODULE))
+		printk(KERN_WARNING "%s:cannot get module\n", __func__);
+	return 0;
+}
+
+static int
+open_bchannel(struct l1oip *hc, struct dchannel *dch, struct channel_req *rq)
+{
+	struct bchannel	*bch;
+	int		ch;
+
+	if (!test_channelmap(rq->adr.channel, dch->dev.channelmap))
+		return -EINVAL;
+	if (rq->protocol == ISDN_P_NONE)
+		return -EINVAL;
+	ch = rq->adr.channel; /* BRI: 1=B1 2=B2  PRI: 1..15,17.. */
+	bch = hc->chan[ch].bch;
+	if (!bch) {
+		printk(KERN_ERR "%s:internal error ch %d has no bch\n",
+		       __func__, ch);
+		return -EINVAL;
+	}
+	if (test_and_set_bit(FLG_OPEN, &bch->Flags))
+		return -EBUSY; /* b-channel can be only open once */
+	bch->ch.protocol = rq->protocol;
+	rq->ch = &bch->ch;
+	if (!try_module_get(THIS_MODULE))
+		printk(KERN_WARNING "%s:cannot get module\n", __func__);
+	return 0;
+}
+
+static int
+l1oip_dctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct mISDNdevice	*dev = container_of(ch, struct mISDNdevice, D);
+	struct dchannel		*dch = container_of(dev, struct dchannel, dev);
+	struct l1oip			*hc = dch->hw;
+	struct channel_req	*rq;
+	int			err = 0;
+
+	if (dch->debug & DEBUG_HW)
+		printk(KERN_DEBUG "%s: cmd:%x %p\n",
+		       __func__, cmd, arg);
+	switch (cmd) {
+	case OPEN_CHANNEL:
+		rq = arg;
+		switch (rq->protocol) {
+		case ISDN_P_TE_S0:
+		case ISDN_P_NT_S0:
+			if (hc->pri) {
+				err = -EINVAL;
+				break;
+			}
+			err = open_dchannel(hc, dch, rq);
+			break;
+		case ISDN_P_TE_E1:
+		case ISDN_P_NT_E1:
+			if (!hc->pri) {
+				err = -EINVAL;
+				break;
+			}
+			err = open_dchannel(hc, dch, rq);
+			break;
+		default:
+			err = open_bchannel(hc, dch, rq);
+		}
+		break;
+	case CLOSE_CHANNEL:
+		if (debug & DEBUG_HW_OPEN)
+			printk(KERN_DEBUG "%s: dev(%d) close from %p\n",
+			       __func__, dch->dev.id,
+			       __builtin_return_address(0));
+		module_put(THIS_MODULE);
+		break;
+	case CONTROL_CHANNEL:
+		err = channel_dctrl(dch, arg);
+		break;
+	default:
+		if (dch->debug & DEBUG_HW)
+			printk(KERN_DEBUG "%s: unknown command %x\n",
+			       __func__, cmd);
+		err = -EINVAL;
+	}
+	return err;
+}
+
+static int
+handle_bmsg(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct bchannel		*bch = container_of(ch, struct bchannel, ch);
+	struct l1oip			*hc = bch->hw;
+	int			ret = -EINVAL;
+	struct mISDNhead	*hh = mISDN_HEAD_P(skb);
+	int			l, ll;
+	unsigned char		*p;
+
+	switch (hh->prim) {
+	case PH_DATA_REQ:
+		if (skb->len <= 0) {
+			printk(KERN_WARNING "%s: skb too small\n",
+			       __func__);
+			break;
+		}
+		if (skb->len > MAX_DFRAME_LEN_L1 || skb->len > L1OIP_MAX_LEN) {
+			printk(KERN_WARNING "%s: skb too large\n",
+			       __func__);
+			break;
+		}
+		/* check for AIS / ulaw-silence */
+		l = skb->len;
+		if (!memchr_inv(skb->data, 0xff, l)) {
+			if (debug & DEBUG_L1OIP_MSG)
+				printk(KERN_DEBUG "%s: got AIS, not sending, "
+				       "but counting\n", __func__);
+			hc->chan[bch->slot].tx_counter += l;
+			skb_trim(skb, 0);
+			queue_ch_frame(ch, PH_DATA_CNF, hh->id, skb);
+			return 0;
+		}
+		/* check for silence */
+		l = skb->len;
+		if (!memchr_inv(skb->data, 0x2a, l)) {
+			if (debug & DEBUG_L1OIP_MSG)
+				printk(KERN_DEBUG "%s: got silence, not sending"
+				       ", but counting\n", __func__);
+			hc->chan[bch->slot].tx_counter += l;
+			skb_trim(skb, 0);
+			queue_ch_frame(ch, PH_DATA_CNF, hh->id, skb);
+			return 0;
+		}
+
+		/* send frame */
+		p = skb->data;
+		l = skb->len;
+		while (l) {
+			/*
+			 * This is technically bounded by L1OIP_MAX_PERFRAME but
+			 * MAX_DFRAME_LEN_L1 < L1OIP_MAX_PERFRAME
+			 */
+			ll = (l < MAX_DFRAME_LEN_L1) ? l : MAX_DFRAME_LEN_L1;
+			l1oip_socket_send(hc, hc->codec, bch->slot, 0,
+					  hc->chan[bch->slot].tx_counter, p, ll);
+			hc->chan[bch->slot].tx_counter += ll;
+			p += ll;
+			l -= ll;
+		}
+		skb_trim(skb, 0);
+		queue_ch_frame(ch, PH_DATA_CNF, hh->id, skb);
+		return 0;
+	case PH_ACTIVATE_REQ:
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: PH_ACTIVATE channel %d (1..%d)\n"
+			       , __func__, bch->slot, hc->b_num + 1);
+		hc->chan[bch->slot].codecstate = 0;
+		test_and_set_bit(FLG_ACTIVE, &bch->Flags);
+		skb_trim(skb, 0);
+		queue_ch_frame(ch, PH_ACTIVATE_IND, hh->id, skb);
+		return 0;
+	case PH_DEACTIVATE_REQ:
+		if (debug & (DEBUG_L1OIP_MSG | DEBUG_L1OIP_SOCKET))
+			printk(KERN_DEBUG "%s: PH_DEACTIVATE channel %d "
+			       "(1..%d)\n", __func__, bch->slot,
+			       hc->b_num + 1);
+		test_and_clear_bit(FLG_ACTIVE, &bch->Flags);
+		skb_trim(skb, 0);
+		queue_ch_frame(ch, PH_DEACTIVATE_IND, hh->id, skb);
+		return 0;
+	}
+	if (!ret)
+		dev_kfree_skb(skb);
+	return ret;
+}
+
+static int
+channel_bctrl(struct bchannel *bch, struct mISDN_ctrl_req *cq)
+{
+	int			ret = 0;
+	struct dsp_features	*features =
+		(struct dsp_features *)(*((u_long *)&cq->p1));
+
+	switch (cq->op) {
+	case MISDN_CTRL_GETOP:
+		cq->op = MISDN_CTRL_HW_FEATURES_OP;
+		break;
+	case MISDN_CTRL_HW_FEATURES: /* fill features structure */
+		if (debug & DEBUG_L1OIP_MSG)
+			printk(KERN_DEBUG "%s: HW_FEATURE request\n",
+			       __func__);
+		/* create confirm */
+		features->unclocked = 1;
+		features->unordered = 1;
+		break;
+	default:
+		printk(KERN_WARNING "%s: unknown Op %x\n",
+		       __func__, cq->op);
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int
+l1oip_bctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct bchannel	*bch = container_of(ch, struct bchannel, ch);
+	int		err = -EINVAL;
+
+	if (bch->debug & DEBUG_HW)
+		printk(KERN_DEBUG "%s: cmd:%x %p\n",
+		       __func__, cmd, arg);
+	switch (cmd) {
+	case CLOSE_CHANNEL:
+		test_and_clear_bit(FLG_OPEN, &bch->Flags);
+		test_and_clear_bit(FLG_ACTIVE, &bch->Flags);
+		ch->protocol = ISDN_P_NONE;
+		ch->peer = NULL;
+		module_put(THIS_MODULE);
+		err = 0;
+		break;
+	case CONTROL_CHANNEL:
+		err = channel_bctrl(bch, arg);
+		break;
+	default:
+		printk(KERN_WARNING "%s: unknown prim(%x)\n",
+		       __func__, cmd);
+	}
+	return err;
+}
+
+
+/*
+ * cleanup module and stack
+ */
+static void
+release_card(struct l1oip *hc)
+{
+	int	ch;
+
+	hc->shutdown = true;
+
+	del_timer_sync(&hc->keep_tl);
+	del_timer_sync(&hc->timeout_tl);
+
+	cancel_work_sync(&hc->workq);
+
+	if (hc->socket_thread)
+		l1oip_socket_close(hc);
+
+	if (hc->registered && hc->chan[hc->d_idx].dch)
+		mISDN_unregister_device(&hc->chan[hc->d_idx].dch->dev);
+	for (ch = 0; ch < 128; ch++) {
+		if (hc->chan[ch].dch) {
+			mISDN_freedchannel(hc->chan[ch].dch);
+			kfree(hc->chan[ch].dch);
+		}
+		if (hc->chan[ch].bch) {
+			mISDN_freebchannel(hc->chan[ch].bch);
+			kfree(hc->chan[ch].bch);
+#ifdef REORDER_DEBUG
+			dev_kfree_skb(hc->chan[ch].disorder_skb);
+#endif
+		}
+	}
+
+	spin_lock(&l1oip_lock);
+	list_del(&hc->list);
+	spin_unlock(&l1oip_lock);
+
+	kfree(hc);
+}
+
+static void
+l1oip_cleanup(void)
+{
+	struct l1oip *hc, *next;
+
+	list_for_each_entry_safe(hc, next, &l1oip_ilist, list)
+		release_card(hc);
+
+	l1oip_4bit_free();
+}
+
+
+/*
+ * module and stack init
+ */
+static int
+init_card(struct l1oip *hc, int pri, int bundle)
+{
+	struct dchannel	*dch;
+	struct bchannel	*bch;
+	int		ret;
+	int		i, ch;
+
+	spin_lock_init(&hc->socket_lock);
+	hc->idx = l1oip_cnt;
+	hc->pri = pri;
+	hc->d_idx = pri ? 16 : 3;
+	hc->b_num = pri ? 30 : 2;
+	hc->bundle = bundle;
+	if (hc->pri)
+		sprintf(hc->name, "l1oip-e1.%d", l1oip_cnt + 1);
+	else
+		sprintf(hc->name, "l1oip-s0.%d", l1oip_cnt + 1);
+
+	switch (codec[l1oip_cnt]) {
+	case 0: /* as is */
+	case 1: /* alaw */
+	case 2: /* ulaw */
+	case 3: /* 4bit */
+		break;
+	default:
+		printk(KERN_ERR "Codec(%d) not supported.\n",
+		       codec[l1oip_cnt]);
+		return -EINVAL;
+	}
+	hc->codec = codec[l1oip_cnt];
+	if (debug & DEBUG_L1OIP_INIT)
+		printk(KERN_DEBUG "%s: using codec %d\n",
+		       __func__, hc->codec);
+
+	if (id[l1oip_cnt] == 0) {
+		printk(KERN_WARNING "Warning: No 'id' value given or "
+		       "0, this is highly unsecure. Please use 32 "
+		       "bit random number 0x...\n");
+	}
+	hc->id = id[l1oip_cnt];
+	if (debug & DEBUG_L1OIP_INIT)
+		printk(KERN_DEBUG "%s: using id 0x%x\n", __func__, hc->id);
+
+	hc->ondemand = ondemand[l1oip_cnt];
+	if (hc->ondemand && !hc->id) {
+		printk(KERN_ERR "%s: ondemand option only allowed in "
+		       "conjunction with non 0 ID\n", __func__);
+		return -EINVAL;
+	}
+
+	if (limit[l1oip_cnt])
+		hc->b_num = limit[l1oip_cnt];
+	if (!pri && hc->b_num > 2) {
+		printk(KERN_ERR "Maximum limit for BRI interface is 2 "
+		       "channels.\n");
+		return -EINVAL;
+	}
+	if (pri && hc->b_num > 126) {
+		printk(KERN_ERR "Maximum limit for PRI interface is 126 "
+		       "channels.\n");
+		return -EINVAL;
+	}
+	if (pri && hc->b_num > 30) {
+		printk(KERN_WARNING "Maximum limit for BRI interface is 30 "
+		       "channels.\n");
+		printk(KERN_WARNING "Your selection of %d channels must be "
+		       "supported by application.\n", hc->limit);
+	}
+
+	hc->remoteip = ip[l1oip_cnt << 2] << 24
+		| ip[(l1oip_cnt << 2) + 1] << 16
+		| ip[(l1oip_cnt << 2) + 2] << 8
+		| ip[(l1oip_cnt << 2) + 3];
+	hc->localport = port[l1oip_cnt]?:(L1OIP_DEFAULTPORT + l1oip_cnt);
+	if (remoteport[l1oip_cnt])
+		hc->remoteport = remoteport[l1oip_cnt];
+	else
+		hc->remoteport = hc->localport;
+	if (debug & DEBUG_L1OIP_INIT)
+		printk(KERN_DEBUG "%s: using local port %d remote ip "
+		       "%d.%d.%d.%d port %d ondemand %d\n", __func__,
+		       hc->localport, hc->remoteip >> 24,
+		       (hc->remoteip >> 16) & 0xff,
+		       (hc->remoteip >> 8) & 0xff, hc->remoteip & 0xff,
+		       hc->remoteport, hc->ondemand);
+
+	dch = kzalloc(sizeof(struct dchannel), GFP_KERNEL);
+	if (!dch)
+		return -ENOMEM;
+	dch->debug = debug;
+	mISDN_initdchannel(dch, MAX_DFRAME_LEN_L1, NULL);
+	dch->hw = hc;
+	if (pri)
+		dch->dev.Dprotocols = (1 << ISDN_P_TE_E1) | (1 << ISDN_P_NT_E1);
+	else
+		dch->dev.Dprotocols = (1 << ISDN_P_TE_S0) | (1 << ISDN_P_NT_S0);
+	dch->dev.Bprotocols = (1 << (ISDN_P_B_RAW & ISDN_P_B_MASK)) |
+		(1 << (ISDN_P_B_HDLC & ISDN_P_B_MASK));
+	dch->dev.D.send = handle_dmsg;
+	dch->dev.D.ctrl = l1oip_dctrl;
+	dch->dev.nrbchan = hc->b_num;
+	dch->slot = hc->d_idx;
+	hc->chan[hc->d_idx].dch = dch;
+	i = 1;
+	for (ch = 0; ch < dch->dev.nrbchan; ch++) {
+		if (ch == 15)
+			i++;
+		bch = kzalloc(sizeof(struct bchannel), GFP_KERNEL);
+		if (!bch) {
+			printk(KERN_ERR "%s: no memory for bchannel\n",
+			       __func__);
+			return -ENOMEM;
+		}
+		bch->nr = i + ch;
+		bch->slot = i + ch;
+		bch->debug = debug;
+		mISDN_initbchannel(bch, MAX_DATA_MEM, 0);
+		bch->hw = hc;
+		bch->ch.send = handle_bmsg;
+		bch->ch.ctrl = l1oip_bctrl;
+		bch->ch.nr = i + ch;
+		list_add(&bch->ch.list, &dch->dev.bchannels);
+		hc->chan[i + ch].bch = bch;
+		set_channelmap(bch->nr, dch->dev.channelmap);
+	}
+	/* TODO: create a parent device for this driver */
+	ret = mISDN_register_device(&dch->dev, NULL, hc->name);
+	if (ret)
+		return ret;
+	hc->registered = 1;
+
+	if (debug & DEBUG_L1OIP_INIT)
+		printk(KERN_DEBUG "%s: Setting up network card(%d)\n",
+		       __func__, l1oip_cnt + 1);
+	ret = l1oip_socket_open(hc);
+	if (ret)
+		return ret;
+
+	timer_setup(&hc->keep_tl, l1oip_keepalive, 0);
+	hc->keep_tl.expires = jiffies + 2 * HZ; /* two seconds first time */
+	add_timer(&hc->keep_tl);
+
+	timer_setup(&hc->timeout_tl, l1oip_timeout, 0);
+	hc->timeout_on = 0; /* state that we have timer off */
+
+	return 0;
+}
+
+static int __init
+l1oip_init(void)
+{
+	int		pri, bundle;
+	struct l1oip		*hc;
+	int		ret;
+
+	printk(KERN_INFO "mISDN: Layer-1-over-IP driver Rev. %s\n",
+	       l1oip_revision);
+
+	if (l1oip_4bit_alloc(ulaw))
+		return -ENOMEM;
+
+	l1oip_cnt = 0;
+	while (l1oip_cnt < MAX_CARDS && type[l1oip_cnt]) {
+		switch (type[l1oip_cnt] & 0xff) {
+		case 1:
+			pri = 0;
+			bundle = 0;
+			break;
+		case 2:
+			pri = 1;
+			bundle = 0;
+			break;
+		case 3:
+			pri = 0;
+			bundle = 1;
+			break;
+		case 4:
+			pri = 1;
+			bundle = 1;
+			break;
+		default:
+			printk(KERN_ERR "Card type(%d) not supported.\n",
+			       type[l1oip_cnt] & 0xff);
+			l1oip_cleanup();
+			return -EINVAL;
+		}
+
+		if (debug & DEBUG_L1OIP_INIT)
+			printk(KERN_DEBUG "%s: interface %d is %s with %s.\n",
+			       __func__, l1oip_cnt, pri ? "PRI" : "BRI",
+			       bundle ? "bundled IP packet for all B-channels" :
+			       "separate IP packets for every B-channel");
+
+		hc = kzalloc(sizeof(struct l1oip), GFP_ATOMIC);
+		if (!hc) {
+			printk(KERN_ERR "No kmem for L1-over-IP driver.\n");
+			l1oip_cleanup();
+			return -ENOMEM;
+		}
+		INIT_WORK(&hc->workq, (void *)l1oip_send_bh);
+
+		spin_lock(&l1oip_lock);
+		list_add_tail(&hc->list, &l1oip_ilist);
+		spin_unlock(&l1oip_lock);
+
+		ret = init_card(hc, pri, bundle);
+		if (ret) {
+			l1oip_cleanup();
+			return ret;
+		}
+
+		l1oip_cnt++;
+	}
+	printk(KERN_INFO "%d virtual devices registered\n", l1oip_cnt);
+	return 0;
+}
+
+module_init(l1oip_init);
+module_exit(l1oip_cleanup);
diff --git a/drivers/isdn/mISDN/layer1.c b/drivers/isdn/mISDN/layer1.c
new file mode 100644
index 000000000..7b31c25a5
--- /dev/null
+++ b/drivers/isdn/mISDN/layer1.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/mISDNhw.h>
+#include "core.h"
+#include "layer1.h"
+#include "fsm.h"
+
+static u_int *debug;
+
+struct layer1 {
+	u_long Flags;
+	struct FsmInst l1m;
+	struct FsmTimer timer3;
+	struct FsmTimer timerX;
+	int delay;
+	int t3_value;
+	struct dchannel *dch;
+	dchannel_l1callback *dcb;
+};
+
+#define TIMER3_DEFAULT_VALUE	7000
+
+static
+struct Fsm l1fsm_s = {NULL, 0, 0, NULL, NULL};
+
+enum {
+	ST_L1_F2,
+	ST_L1_F3,
+	ST_L1_F4,
+	ST_L1_F5,
+	ST_L1_F6,
+	ST_L1_F7,
+	ST_L1_F8,
+};
+
+#define L1S_STATE_COUNT (ST_L1_F8 + 1)
+
+static char *strL1SState[] =
+{
+	"ST_L1_F2",
+	"ST_L1_F3",
+	"ST_L1_F4",
+	"ST_L1_F5",
+	"ST_L1_F6",
+	"ST_L1_F7",
+	"ST_L1_F8",
+};
+
+enum {
+	EV_PH_ACTIVATE,
+	EV_PH_DEACTIVATE,
+	EV_RESET_IND,
+	EV_DEACT_CNF,
+	EV_DEACT_IND,
+	EV_POWER_UP,
+	EV_ANYSIG_IND,
+	EV_INFO2_IND,
+	EV_INFO4_IND,
+	EV_TIMER_DEACT,
+	EV_TIMER_ACT,
+	EV_TIMER3,
+};
+
+#define L1_EVENT_COUNT (EV_TIMER3 + 1)
+
+static char *strL1Event[] =
+{
+	"EV_PH_ACTIVATE",
+	"EV_PH_DEACTIVATE",
+	"EV_RESET_IND",
+	"EV_DEACT_CNF",
+	"EV_DEACT_IND",
+	"EV_POWER_UP",
+	"EV_ANYSIG_IND",
+	"EV_INFO2_IND",
+	"EV_INFO4_IND",
+	"EV_TIMER_DEACT",
+	"EV_TIMER_ACT",
+	"EV_TIMER3",
+};
+
+static void
+l1m_debug(struct FsmInst *fi, char *fmt, ...)
+{
+	struct layer1 *l1 = fi->userdata;
+	struct va_format vaf;
+	va_list va;
+
+	va_start(va, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "%s: %pV\n", dev_name(&l1->dch->dev.dev), &vaf);
+
+	va_end(va);
+}
+
+static void
+l1_reset(struct FsmInst *fi, int event, void *arg)
+{
+	mISDN_FsmChangeState(fi, ST_L1_F3);
+}
+
+static void
+l1_deact_cnf(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	mISDN_FsmChangeState(fi, ST_L1_F3);
+	if (test_bit(FLG_L1_ACTIVATING, &l1->Flags))
+		l1->dcb(l1->dch, HW_POWERUP_REQ);
+}
+
+static void
+l1_deact_req_s(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	mISDN_FsmChangeState(fi, ST_L1_F3);
+	mISDN_FsmRestartTimer(&l1->timerX, 550, EV_TIMER_DEACT, NULL, 2);
+	test_and_set_bit(FLG_L1_DEACTTIMER, &l1->Flags);
+}
+
+static void
+l1_power_up_s(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	if (test_bit(FLG_L1_ACTIVATING, &l1->Flags)) {
+		mISDN_FsmChangeState(fi, ST_L1_F4);
+		l1->dcb(l1->dch, INFO3_P8);
+	} else
+		mISDN_FsmChangeState(fi, ST_L1_F3);
+}
+
+static void
+l1_go_F5(struct FsmInst *fi, int event, void *arg)
+{
+	mISDN_FsmChangeState(fi, ST_L1_F5);
+}
+
+static void
+l1_go_F8(struct FsmInst *fi, int event, void *arg)
+{
+	mISDN_FsmChangeState(fi, ST_L1_F8);
+}
+
+static void
+l1_info2_ind(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	mISDN_FsmChangeState(fi, ST_L1_F6);
+	l1->dcb(l1->dch, INFO3_P8);
+}
+
+static void
+l1_info4_ind(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	mISDN_FsmChangeState(fi, ST_L1_F7);
+	l1->dcb(l1->dch, INFO3_P8);
+	if (test_and_clear_bit(FLG_L1_DEACTTIMER, &l1->Flags))
+		mISDN_FsmDelTimer(&l1->timerX, 4);
+	if (!test_bit(FLG_L1_ACTIVATED, &l1->Flags)) {
+		if (test_and_clear_bit(FLG_L1_T3RUN, &l1->Flags))
+			mISDN_FsmDelTimer(&l1->timer3, 3);
+		mISDN_FsmRestartTimer(&l1->timerX, 110, EV_TIMER_ACT, NULL, 2);
+		test_and_set_bit(FLG_L1_ACTTIMER, &l1->Flags);
+	}
+}
+
+static void
+l1_timer3(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	test_and_clear_bit(FLG_L1_T3RUN, &l1->Flags);
+	if (test_and_clear_bit(FLG_L1_ACTIVATING, &l1->Flags)) {
+		if (test_and_clear_bit(FLG_L1_DBLOCKED, &l1->Flags))
+			l1->dcb(l1->dch, HW_D_NOBLOCKED);
+		l1->dcb(l1->dch, PH_DEACTIVATE_IND);
+	}
+	if (l1->l1m.state != ST_L1_F6) {
+		mISDN_FsmChangeState(fi, ST_L1_F3);
+		/* do not force anything here, we need send INFO 0 */
+	}
+}
+
+static void
+l1_timer_act(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	test_and_clear_bit(FLG_L1_ACTTIMER, &l1->Flags);
+	test_and_set_bit(FLG_L1_ACTIVATED, &l1->Flags);
+	l1->dcb(l1->dch, PH_ACTIVATE_IND);
+}
+
+static void
+l1_timer_deact(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	test_and_clear_bit(FLG_L1_DEACTTIMER, &l1->Flags);
+	test_and_clear_bit(FLG_L1_ACTIVATED, &l1->Flags);
+	if (test_and_clear_bit(FLG_L1_DBLOCKED, &l1->Flags))
+		l1->dcb(l1->dch, HW_D_NOBLOCKED);
+	l1->dcb(l1->dch, PH_DEACTIVATE_IND);
+	l1->dcb(l1->dch, HW_DEACT_REQ);
+}
+
+static void
+l1_activate_s(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	mISDN_FsmRestartTimer(&l1->timer3, l1->t3_value, EV_TIMER3, NULL, 2);
+	test_and_set_bit(FLG_L1_T3RUN, &l1->Flags);
+	/* Tell HW to send INFO 1 */
+	l1->dcb(l1->dch, HW_RESET_REQ);
+}
+
+static void
+l1_activate_no(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer1 *l1 = fi->userdata;
+
+	if ((!test_bit(FLG_L1_DEACTTIMER, &l1->Flags)) &&
+	    (!test_bit(FLG_L1_T3RUN, &l1->Flags))) {
+		test_and_clear_bit(FLG_L1_ACTIVATING, &l1->Flags);
+		if (test_and_clear_bit(FLG_L1_DBLOCKED, &l1->Flags))
+			l1->dcb(l1->dch, HW_D_NOBLOCKED);
+		l1->dcb(l1->dch, PH_DEACTIVATE_IND);
+	}
+}
+
+static struct FsmNode L1SFnList[] =
+{
+	{ST_L1_F3, EV_PH_ACTIVATE, l1_activate_s},
+	{ST_L1_F6, EV_PH_ACTIVATE, l1_activate_no},
+	{ST_L1_F8, EV_PH_ACTIVATE, l1_activate_no},
+	{ST_L1_F3, EV_RESET_IND, l1_reset},
+	{ST_L1_F4, EV_RESET_IND, l1_reset},
+	{ST_L1_F5, EV_RESET_IND, l1_reset},
+	{ST_L1_F6, EV_RESET_IND, l1_reset},
+	{ST_L1_F7, EV_RESET_IND, l1_reset},
+	{ST_L1_F8, EV_RESET_IND, l1_reset},
+	{ST_L1_F3, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F4, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F5, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F6, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F7, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F8, EV_DEACT_CNF, l1_deact_cnf},
+	{ST_L1_F6, EV_DEACT_IND, l1_deact_req_s},
+	{ST_L1_F7, EV_DEACT_IND, l1_deact_req_s},
+	{ST_L1_F8, EV_DEACT_IND, l1_deact_req_s},
+	{ST_L1_F3, EV_POWER_UP,  l1_power_up_s},
+	{ST_L1_F4, EV_ANYSIG_IND, l1_go_F5},
+	{ST_L1_F6, EV_ANYSIG_IND, l1_go_F8},
+	{ST_L1_F7, EV_ANYSIG_IND, l1_go_F8},
+	{ST_L1_F3, EV_INFO2_IND, l1_info2_ind},
+	{ST_L1_F4, EV_INFO2_IND, l1_info2_ind},
+	{ST_L1_F5, EV_INFO2_IND, l1_info2_ind},
+	{ST_L1_F7, EV_INFO2_IND, l1_info2_ind},
+	{ST_L1_F8, EV_INFO2_IND, l1_info2_ind},
+	{ST_L1_F3, EV_INFO4_IND, l1_info4_ind},
+	{ST_L1_F4, EV_INFO4_IND, l1_info4_ind},
+	{ST_L1_F5, EV_INFO4_IND, l1_info4_ind},
+	{ST_L1_F6, EV_INFO4_IND, l1_info4_ind},
+	{ST_L1_F8, EV_INFO4_IND, l1_info4_ind},
+	{ST_L1_F3, EV_TIMER3, l1_timer3},
+	{ST_L1_F4, EV_TIMER3, l1_timer3},
+	{ST_L1_F5, EV_TIMER3, l1_timer3},
+	{ST_L1_F6, EV_TIMER3, l1_timer3},
+	{ST_L1_F8, EV_TIMER3, l1_timer3},
+	{ST_L1_F7, EV_TIMER_ACT, l1_timer_act},
+	{ST_L1_F3, EV_TIMER_DEACT, l1_timer_deact},
+	{ST_L1_F4, EV_TIMER_DEACT, l1_timer_deact},
+	{ST_L1_F5, EV_TIMER_DEACT, l1_timer_deact},
+	{ST_L1_F6, EV_TIMER_DEACT, l1_timer_deact},
+	{ST_L1_F7, EV_TIMER_DEACT, l1_timer_deact},
+	{ST_L1_F8, EV_TIMER_DEACT, l1_timer_deact},
+};
+
+static void
+release_l1(struct layer1 *l1) {
+	mISDN_FsmDelTimer(&l1->timerX, 0);
+	mISDN_FsmDelTimer(&l1->timer3, 0);
+	if (l1->dch)
+		l1->dch->l1 = NULL;
+	module_put(THIS_MODULE);
+	kfree(l1);
+}
+
+int
+l1_event(struct layer1 *l1, u_int event)
+{
+	int		err = 0;
+
+	if (!l1)
+		return -EINVAL;
+	switch (event) {
+	case HW_RESET_IND:
+		mISDN_FsmEvent(&l1->l1m, EV_RESET_IND, NULL);
+		break;
+	case HW_DEACT_IND:
+		mISDN_FsmEvent(&l1->l1m, EV_DEACT_IND, NULL);
+		break;
+	case HW_POWERUP_IND:
+		mISDN_FsmEvent(&l1->l1m, EV_POWER_UP, NULL);
+		break;
+	case HW_DEACT_CNF:
+		mISDN_FsmEvent(&l1->l1m, EV_DEACT_CNF, NULL);
+		break;
+	case ANYSIGNAL:
+		mISDN_FsmEvent(&l1->l1m, EV_ANYSIG_IND, NULL);
+		break;
+	case LOSTFRAMING:
+		mISDN_FsmEvent(&l1->l1m, EV_ANYSIG_IND, NULL);
+		break;
+	case INFO2:
+		mISDN_FsmEvent(&l1->l1m, EV_INFO2_IND, NULL);
+		break;
+	case INFO4_P8:
+		mISDN_FsmEvent(&l1->l1m, EV_INFO4_IND, NULL);
+		break;
+	case INFO4_P10:
+		mISDN_FsmEvent(&l1->l1m, EV_INFO4_IND, NULL);
+		break;
+	case PH_ACTIVATE_REQ:
+		if (test_bit(FLG_L1_ACTIVATED, &l1->Flags))
+			l1->dcb(l1->dch, PH_ACTIVATE_IND);
+		else {
+			test_and_set_bit(FLG_L1_ACTIVATING, &l1->Flags);
+			mISDN_FsmEvent(&l1->l1m, EV_PH_ACTIVATE, NULL);
+		}
+		break;
+	case CLOSE_CHANNEL:
+		release_l1(l1);
+		break;
+	default:
+		if ((event & ~HW_TIMER3_VMASK) == HW_TIMER3_VALUE) {
+			int val = event & HW_TIMER3_VMASK;
+
+			if (val < 5)
+				val = 5;
+			if (val > 30)
+				val = 30;
+			l1->t3_value = val;
+			break;
+		}
+		if (*debug & DEBUG_L1)
+			printk(KERN_DEBUG "%s %x unhandled\n",
+			       __func__, event);
+		err = -EINVAL;
+	}
+	return err;
+}
+EXPORT_SYMBOL(l1_event);
+
+int
+create_l1(struct dchannel *dch, dchannel_l1callback *dcb) {
+	struct layer1	*nl1;
+
+	nl1 = kzalloc(sizeof(struct layer1), GFP_ATOMIC);
+	if (!nl1) {
+		printk(KERN_ERR "kmalloc struct layer1 failed\n");
+		return -ENOMEM;
+	}
+	nl1->l1m.fsm = &l1fsm_s;
+	nl1->l1m.state = ST_L1_F3;
+	nl1->Flags = 0;
+	nl1->t3_value = TIMER3_DEFAULT_VALUE;
+	nl1->l1m.debug = *debug & DEBUG_L1_FSM;
+	nl1->l1m.userdata = nl1;
+	nl1->l1m.userint = 0;
+	nl1->l1m.printdebug = l1m_debug;
+	nl1->dch = dch;
+	nl1->dcb = dcb;
+	mISDN_FsmInitTimer(&nl1->l1m, &nl1->timer3);
+	mISDN_FsmInitTimer(&nl1->l1m, &nl1->timerX);
+	__module_get(THIS_MODULE);
+	dch->l1 = nl1;
+	return 0;
+}
+EXPORT_SYMBOL(create_l1);
+
+int
+Isdnl1_Init(u_int *deb)
+{
+	debug = deb;
+	l1fsm_s.state_count = L1S_STATE_COUNT;
+	l1fsm_s.event_count = L1_EVENT_COUNT;
+	l1fsm_s.strEvent = strL1Event;
+	l1fsm_s.strState = strL1SState;
+	return mISDN_FsmNew(&l1fsm_s, L1SFnList, ARRAY_SIZE(L1SFnList));
+}
+
+void
+Isdnl1_cleanup(void)
+{
+	mISDN_FsmFree(&l1fsm_s);
+}
diff --git a/drivers/isdn/mISDN/layer1.h b/drivers/isdn/mISDN/layer1.h
new file mode 100644
index 000000000..f03e86450
--- /dev/null
+++ b/drivers/isdn/mISDN/layer1.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *
+ * Layer 1 defines
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#define FLG_L1_ACTIVATING	1
+#define FLG_L1_ACTIVATED	2
+#define FLG_L1_DEACTTIMER	3
+#define FLG_L1_ACTTIMER		4
+#define FLG_L1_T3RUN		5
+#define FLG_L1_PULL_REQ		6
+#define FLG_L1_UINT		7
+#define FLG_L1_DBLOCKED		8
diff --git a/drivers/isdn/mISDN/layer2.c b/drivers/isdn/mISDN/layer2.c
new file mode 100644
index 000000000..5bf7fcb28
--- /dev/null
+++ b/drivers/isdn/mISDN/layer2.c
@@ -0,0 +1,2266 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/mISDNif.h>
+#include <linux/slab.h>
+#include "core.h"
+#include "fsm.h"
+#include "layer2.h"
+
+static u_int *debug;
+
+static
+struct Fsm l2fsm = {NULL, 0, 0, NULL, NULL};
+
+static char *strL2State[] =
+{
+	"ST_L2_1",
+	"ST_L2_2",
+	"ST_L2_3",
+	"ST_L2_4",
+	"ST_L2_5",
+	"ST_L2_6",
+	"ST_L2_7",
+	"ST_L2_8",
+};
+
+enum {
+	EV_L2_UI,
+	EV_L2_SABME,
+	EV_L2_DISC,
+	EV_L2_DM,
+	EV_L2_UA,
+	EV_L2_FRMR,
+	EV_L2_SUPER,
+	EV_L2_I,
+	EV_L2_DL_DATA,
+	EV_L2_ACK_PULL,
+	EV_L2_DL_UNITDATA,
+	EV_L2_DL_ESTABLISH_REQ,
+	EV_L2_DL_RELEASE_REQ,
+	EV_L2_MDL_ASSIGN,
+	EV_L2_MDL_REMOVE,
+	EV_L2_MDL_ERROR,
+	EV_L1_DEACTIVATE,
+	EV_L2_T200,
+	EV_L2_T203,
+	EV_L2_T200I,
+	EV_L2_T203I,
+	EV_L2_SET_OWN_BUSY,
+	EV_L2_CLEAR_OWN_BUSY,
+	EV_L2_FRAME_ERROR,
+};
+
+#define L2_EVENT_COUNT (EV_L2_FRAME_ERROR + 1)
+
+static char *strL2Event[] =
+{
+	"EV_L2_UI",
+	"EV_L2_SABME",
+	"EV_L2_DISC",
+	"EV_L2_DM",
+	"EV_L2_UA",
+	"EV_L2_FRMR",
+	"EV_L2_SUPER",
+	"EV_L2_I",
+	"EV_L2_DL_DATA",
+	"EV_L2_ACK_PULL",
+	"EV_L2_DL_UNITDATA",
+	"EV_L2_DL_ESTABLISH_REQ",
+	"EV_L2_DL_RELEASE_REQ",
+	"EV_L2_MDL_ASSIGN",
+	"EV_L2_MDL_REMOVE",
+	"EV_L2_MDL_ERROR",
+	"EV_L1_DEACTIVATE",
+	"EV_L2_T200",
+	"EV_L2_T203",
+	"EV_L2_T200I",
+	"EV_L2_T203I",
+	"EV_L2_SET_OWN_BUSY",
+	"EV_L2_CLEAR_OWN_BUSY",
+	"EV_L2_FRAME_ERROR",
+};
+
+static void
+l2m_debug(struct FsmInst *fi, char *fmt, ...)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct va_format vaf;
+	va_list va;
+
+	if (!(*debug & DEBUG_L2_FSM))
+		return;
+
+	va_start(va, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "%s l2 (sapi %d tei %d): %pV\n",
+	       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei, &vaf);
+
+	va_end(va);
+}
+
+inline u_int
+l2headersize(struct layer2 *l2, int ui)
+{
+	return ((test_bit(FLG_MOD128, &l2->flag) && (!ui)) ? 2 : 1) +
+		(test_bit(FLG_LAPD, &l2->flag) ? 2 : 1);
+}
+
+inline u_int
+l2addrsize(struct layer2 *l2)
+{
+	return test_bit(FLG_LAPD, &l2->flag) ? 2 : 1;
+}
+
+static u_int
+l2_newid(struct layer2 *l2)
+{
+	u_int	id;
+
+	id = l2->next_id++;
+	if (id == 0x7fff)
+		l2->next_id = 1;
+	id <<= 16;
+	id |= l2->tei << 8;
+	id |= l2->sapi;
+	return id;
+}
+
+static void
+l2up(struct layer2 *l2, u_int prim, struct sk_buff *skb)
+{
+	int	err;
+
+	if (!l2->up)
+		return;
+	mISDN_HEAD_PRIM(skb) = prim;
+	mISDN_HEAD_ID(skb) = (l2->ch.nr << 16) | l2->ch.addr;
+	err = l2->up->send(l2->up, skb);
+	if (err) {
+		printk(KERN_WARNING "%s: dev %s err=%d\n", __func__,
+		       mISDNDevName4ch(&l2->ch), err);
+		dev_kfree_skb(skb);
+	}
+}
+
+static void
+l2up_create(struct layer2 *l2, u_int prim, int len, void *arg)
+{
+	struct sk_buff	*skb;
+	struct mISDNhead *hh;
+	int		err;
+
+	if (!l2->up)
+		return;
+	skb = mI_alloc_skb(len, GFP_ATOMIC);
+	if (!skb)
+		return;
+	hh = mISDN_HEAD_P(skb);
+	hh->prim = prim;
+	hh->id = (l2->ch.nr << 16) | l2->ch.addr;
+	if (len)
+		skb_put_data(skb, arg, len);
+	err = l2->up->send(l2->up, skb);
+	if (err) {
+		printk(KERN_WARNING "%s: dev %s err=%d\n", __func__,
+		       mISDNDevName4ch(&l2->ch), err);
+		dev_kfree_skb(skb);
+	}
+}
+
+static int
+l2down_skb(struct layer2 *l2, struct sk_buff *skb) {
+	int ret;
+
+	ret = l2->ch.recv(l2->ch.peer, skb);
+	if (ret && (*debug & DEBUG_L2_RECV))
+		printk(KERN_DEBUG "l2down_skb: dev %s ret(%d)\n",
+		       mISDNDevName4ch(&l2->ch), ret);
+	return ret;
+}
+
+static int
+l2down_raw(struct layer2 *l2, struct sk_buff *skb)
+{
+	struct mISDNhead *hh = mISDN_HEAD_P(skb);
+
+	if (hh->prim == PH_DATA_REQ) {
+		if (test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
+			skb_queue_tail(&l2->down_queue, skb);
+			return 0;
+		}
+		l2->down_id = mISDN_HEAD_ID(skb);
+	}
+	return l2down_skb(l2, skb);
+}
+
+static int
+l2down(struct layer2 *l2, u_int prim, u_int id, struct sk_buff *skb)
+{
+	struct mISDNhead *hh = mISDN_HEAD_P(skb);
+
+	hh->prim = prim;
+	hh->id = id;
+	return l2down_raw(l2, skb);
+}
+
+static int
+l2down_create(struct layer2 *l2, u_int prim, u_int id, int len, void *arg)
+{
+	struct sk_buff	*skb;
+	int		err;
+	struct mISDNhead *hh;
+
+	skb = mI_alloc_skb(len, GFP_ATOMIC);
+	if (!skb)
+		return -ENOMEM;
+	hh = mISDN_HEAD_P(skb);
+	hh->prim = prim;
+	hh->id = id;
+	if (len)
+		skb_put_data(skb, arg, len);
+	err = l2down_raw(l2, skb);
+	if (err)
+		dev_kfree_skb(skb);
+	return err;
+}
+
+static int
+ph_data_confirm(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb) {
+	struct sk_buff *nskb = skb;
+	int ret = -EAGAIN;
+
+	if (test_bit(FLG_L1_NOTREADY, &l2->flag)) {
+		if (hh->id == l2->down_id) {
+			nskb = skb_dequeue(&l2->down_queue);
+			if (nskb) {
+				l2->down_id = mISDN_HEAD_ID(nskb);
+				if (l2down_skb(l2, nskb)) {
+					dev_kfree_skb(nskb);
+					l2->down_id = MISDN_ID_NONE;
+				}
+			} else
+				l2->down_id = MISDN_ID_NONE;
+			if (ret) {
+				dev_kfree_skb(skb);
+				ret = 0;
+			}
+			if (l2->down_id == MISDN_ID_NONE) {
+				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
+				mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
+			}
+		}
+	}
+	if (!test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
+		nskb = skb_dequeue(&l2->down_queue);
+		if (nskb) {
+			l2->down_id = mISDN_HEAD_ID(nskb);
+			if (l2down_skb(l2, nskb)) {
+				dev_kfree_skb(nskb);
+				l2->down_id = MISDN_ID_NONE;
+				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
+			}
+		} else
+			test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
+	}
+	return ret;
+}
+
+static void
+l2_timeout(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb;
+	struct mISDNhead *hh;
+
+	skb = mI_alloc_skb(0, GFP_ATOMIC);
+	if (!skb) {
+		printk(KERN_WARNING "%s: L2(%d,%d) nr:%x timer %s no skb\n",
+		       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei,
+		       l2->ch.nr, event == EV_L2_T200 ? "T200" : "T203");
+		return;
+	}
+	hh = mISDN_HEAD_P(skb);
+	hh->prim = event == EV_L2_T200 ? DL_TIMER200_IND : DL_TIMER203_IND;
+	hh->id = l2->ch.nr;
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s: L2(%d,%d) nr:%x timer %s expired\n",
+		       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei,
+		       l2->ch.nr, event == EV_L2_T200 ? "T200" : "T203");
+	if (l2->ch.st)
+		l2->ch.st->own.recv(&l2->ch.st->own, skb);
+}
+
+static int
+l2mgr(struct layer2 *l2, u_int prim, void *arg) {
+	long c = (long)arg;
+
+	printk(KERN_WARNING "l2mgr: dev %s addr:%x prim %x %c\n",
+	       mISDNDevName4ch(&l2->ch), l2->id, prim, (char)c);
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    !test_bit(FLG_FIXED_TEI, &l2->flag)) {
+		switch (c) {
+		case 'C':
+		case 'D':
+		case 'G':
+		case 'H':
+			l2_tei(l2, prim, (u_long)arg);
+			break;
+		}
+	}
+	return 0;
+}
+
+static void
+set_peer_busy(struct layer2 *l2) {
+	test_and_set_bit(FLG_PEER_BUSY, &l2->flag);
+	if (skb_queue_len(&l2->i_queue) || skb_queue_len(&l2->ui_queue))
+		test_and_set_bit(FLG_L2BLOCK, &l2->flag);
+}
+
+static void
+clear_peer_busy(struct layer2 *l2) {
+	if (test_and_clear_bit(FLG_PEER_BUSY, &l2->flag))
+		test_and_clear_bit(FLG_L2BLOCK, &l2->flag);
+}
+
+static void
+InitWin(struct layer2 *l2)
+{
+	int i;
+
+	for (i = 0; i < MAX_WINDOW; i++)
+		l2->windowar[i] = NULL;
+}
+
+static int
+freewin(struct layer2 *l2)
+{
+	int i, cnt = 0;
+
+	for (i = 0; i < MAX_WINDOW; i++) {
+		if (l2->windowar[i]) {
+			cnt++;
+			dev_kfree_skb(l2->windowar[i]);
+			l2->windowar[i] = NULL;
+		}
+	}
+	return cnt;
+}
+
+static void
+ReleaseWin(struct layer2 *l2)
+{
+	int cnt = freewin(l2);
+
+	if (cnt)
+		printk(KERN_WARNING
+		       "isdnl2 freed %d skbuffs in release\n", cnt);
+}
+
+inline unsigned int
+cansend(struct layer2 *l2)
+{
+	unsigned int p1;
+
+	if (test_bit(FLG_MOD128, &l2->flag))
+		p1 = (l2->vs - l2->va) % 128;
+	else
+		p1 = (l2->vs - l2->va) % 8;
+	return (p1 < l2->window) && !test_bit(FLG_PEER_BUSY, &l2->flag);
+}
+
+inline void
+clear_exception(struct layer2 *l2)
+{
+	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+	test_and_clear_bit(FLG_REJEXC, &l2->flag);
+	test_and_clear_bit(FLG_OWN_BUSY, &l2->flag);
+	clear_peer_busy(l2);
+}
+
+static int
+sethdraddr(struct layer2 *l2, u_char *header, int rsp)
+{
+	u_char *ptr = header;
+	int crbit = rsp;
+
+	if (test_bit(FLG_LAPD, &l2->flag)) {
+		if (test_bit(FLG_LAPD_NET, &l2->flag))
+			crbit = !crbit;
+		*ptr++ = (l2->sapi << 2) | (crbit ? 2 : 0);
+		*ptr++ = (l2->tei << 1) | 1;
+		return 2;
+	} else {
+		if (test_bit(FLG_ORIG, &l2->flag))
+			crbit = !crbit;
+		if (crbit)
+			*ptr++ = l2->addr.B;
+		else
+			*ptr++ = l2->addr.A;
+		return 1;
+	}
+}
+
+static inline void
+enqueue_super(struct layer2 *l2, struct sk_buff *skb)
+{
+	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
+		dev_kfree_skb(skb);
+}
+
+static inline void
+enqueue_ui(struct layer2 *l2, struct sk_buff *skb)
+{
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_UI_IND, 0);
+	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
+		dev_kfree_skb(skb);
+}
+
+inline int
+IsUI(u_char *data)
+{
+	return (data[0] & 0xef) == UI;
+}
+
+inline int
+IsUA(u_char *data)
+{
+	return (data[0] & 0xef) == UA;
+}
+
+inline int
+IsDM(u_char *data)
+{
+	return (data[0] & 0xef) == DM;
+}
+
+inline int
+IsDISC(u_char *data)
+{
+	return (data[0] & 0xef) == DISC;
+}
+
+inline int
+IsRR(u_char *data, struct layer2 *l2)
+{
+	if (test_bit(FLG_MOD128, &l2->flag))
+		return data[0] == RR;
+	else
+		return (data[0] & 0xf) == 1;
+}
+
+inline int
+IsSFrame(u_char *data, struct layer2 *l2)
+{
+	register u_char d = *data;
+
+	if (!test_bit(FLG_MOD128, &l2->flag))
+		d &= 0xf;
+	return ((d & 0xf3) == 1) && ((d & 0x0c) != 0x0c);
+}
+
+inline int
+IsSABME(u_char *data, struct layer2 *l2)
+{
+	u_char d = data[0] & ~0x10;
+
+	return test_bit(FLG_MOD128, &l2->flag) ? d == SABME : d == SABM;
+}
+
+inline int
+IsREJ(u_char *data, struct layer2 *l2)
+{
+	return test_bit(FLG_MOD128, &l2->flag) ?
+		data[0] == REJ : (data[0] & 0xf) == REJ;
+}
+
+inline int
+IsFRMR(u_char *data)
+{
+	return (data[0] & 0xef) == FRMR;
+}
+
+inline int
+IsRNR(u_char *data, struct layer2 *l2)
+{
+	return test_bit(FLG_MOD128, &l2->flag) ?
+		data[0] == RNR : (data[0] & 0xf) == RNR;
+}
+
+static int
+iframe_error(struct layer2 *l2, struct sk_buff *skb)
+{
+	u_int	i;
+	int	rsp = *skb->data & 0x2;
+
+	i = l2addrsize(l2) + (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1);
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+	if (rsp)
+		return 'L';
+	if (skb->len < i)
+		return 'N';
+	if ((skb->len - i) > l2->maxlen)
+		return 'O';
+	return 0;
+}
+
+static int
+super_error(struct layer2 *l2, struct sk_buff *skb)
+{
+	if (skb->len != l2addrsize(l2) +
+	    (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1))
+		return 'N';
+	return 0;
+}
+
+static int
+unnum_error(struct layer2 *l2, struct sk_buff *skb, int wantrsp)
+{
+	int rsp = (*skb->data & 0x2) >> 1;
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+	if (rsp != wantrsp)
+		return 'L';
+	if (skb->len != l2addrsize(l2) + 1)
+		return 'N';
+	return 0;
+}
+
+static int
+UI_error(struct layer2 *l2, struct sk_buff *skb)
+{
+	int rsp = *skb->data & 0x2;
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+	if (rsp)
+		return 'L';
+	if (skb->len > l2->maxlen + l2addrsize(l2) + 1)
+		return 'O';
+	return 0;
+}
+
+static int
+FRMR_error(struct layer2 *l2, struct sk_buff *skb)
+{
+	u_int	headers = l2addrsize(l2) + 1;
+	u_char	*datap = skb->data + headers;
+	int	rsp = *skb->data & 0x2;
+
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+	if (!rsp)
+		return 'L';
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		if (skb->len < headers + 5)
+			return 'N';
+		else if (*debug & DEBUG_L2)
+			l2m_debug(&l2->l2m,
+				  "FRMR information %2x %2x %2x %2x %2x",
+				  datap[0], datap[1], datap[2], datap[3], datap[4]);
+	} else {
+		if (skb->len < headers + 3)
+			return 'N';
+		else if (*debug & DEBUG_L2)
+			l2m_debug(&l2->l2m,
+				  "FRMR information %2x %2x %2x",
+				  datap[0], datap[1], datap[2]);
+	}
+	return 0;
+}
+
+static unsigned int
+legalnr(struct layer2 *l2, unsigned int nr)
+{
+	if (test_bit(FLG_MOD128, &l2->flag))
+		return ((nr - l2->va) % 128) <= ((l2->vs - l2->va) % 128);
+	else
+		return ((nr - l2->va) % 8) <= ((l2->vs - l2->va) % 8);
+}
+
+static void
+setva(struct layer2 *l2, unsigned int nr)
+{
+	struct sk_buff	*skb;
+
+	while (l2->va != nr) {
+		l2->va++;
+		if (test_bit(FLG_MOD128, &l2->flag))
+			l2->va %= 128;
+		else
+			l2->va %= 8;
+		if (l2->windowar[l2->sow]) {
+			skb_trim(l2->windowar[l2->sow], 0);
+			skb_queue_tail(&l2->tmp_queue, l2->windowar[l2->sow]);
+			l2->windowar[l2->sow] = NULL;
+		}
+		l2->sow = (l2->sow + 1) % l2->window;
+	}
+	skb = skb_dequeue(&l2->tmp_queue);
+	while (skb) {
+		dev_kfree_skb(skb);
+		skb = skb_dequeue(&l2->tmp_queue);
+	}
+}
+
+static void
+send_uframe(struct layer2 *l2, struct sk_buff *skb, u_char cmd, u_char cr)
+{
+	u_char tmp[MAX_L2HEADER_LEN];
+	int i;
+
+	i = sethdraddr(l2, tmp, cr);
+	tmp[i++] = cmd;
+	if (skb)
+		skb_trim(skb, 0);
+	else {
+		skb = mI_alloc_skb(i, GFP_ATOMIC);
+		if (!skb) {
+			printk(KERN_WARNING "%s: can't alloc skbuff in %s\n",
+			       mISDNDevName4ch(&l2->ch), __func__);
+			return;
+		}
+	}
+	skb_put_data(skb, tmp, i);
+	enqueue_super(l2, skb);
+}
+
+
+inline u_char
+get_PollFlag(struct layer2 *l2, struct sk_buff *skb)
+{
+	return skb->data[l2addrsize(l2)] & 0x10;
+}
+
+inline u_char
+get_PollFlagFree(struct layer2 *l2, struct sk_buff *skb)
+{
+	u_char PF;
+
+	PF = get_PollFlag(l2, skb);
+	dev_kfree_skb(skb);
+	return PF;
+}
+
+inline void
+start_t200(struct layer2 *l2, int i)
+{
+	mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
+	test_and_set_bit(FLG_T200_RUN, &l2->flag);
+}
+
+inline void
+restart_t200(struct layer2 *l2, int i)
+{
+	mISDN_FsmRestartTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
+	test_and_set_bit(FLG_T200_RUN, &l2->flag);
+}
+
+inline void
+stop_t200(struct layer2 *l2, int i)
+{
+	if (test_and_clear_bit(FLG_T200_RUN, &l2->flag))
+		mISDN_FsmDelTimer(&l2->t200, i);
+}
+
+inline void
+st5_dl_release_l2l3(struct layer2 *l2)
+{
+	int pr;
+
+	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
+		pr = DL_RELEASE_CNF;
+	else
+		pr = DL_RELEASE_IND;
+	l2up_create(l2, pr, 0, NULL);
+}
+
+inline void
+lapb_dl_release_l2l3(struct layer2 *l2, int f)
+{
+	if (test_bit(FLG_LAPB, &l2->flag))
+		l2down_create(l2, PH_DEACTIVATE_REQ, l2_newid(l2), 0, NULL);
+	l2up_create(l2, f, 0, NULL);
+}
+
+static void
+establishlink(struct FsmInst *fi)
+{
+	struct layer2 *l2 = fi->userdata;
+	u_char cmd;
+
+	clear_exception(l2);
+	l2->rc = 0;
+	cmd = (test_bit(FLG_MOD128, &l2->flag) ? SABME : SABM) | 0x10;
+	send_uframe(l2, NULL, cmd, CMD);
+	mISDN_FsmDelTimer(&l2->t203, 1);
+	restart_t200(l2, 1);
+	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
+	freewin(l2);
+	mISDN_FsmChangeState(fi, ST_L2_5);
+}
+
+static void
+l2_mdl_error_ua(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	if (get_PollFlagFree(l2, skb))
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'C');
+	else
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'D');
+
+}
+
+static void
+l2_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	if (get_PollFlagFree(l2, skb))
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
+	else {
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
+		establishlink(fi);
+		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+	}
+}
+
+static void
+l2_st8_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	if (get_PollFlagFree(l2, skb))
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
+	else
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
+	establishlink(fi);
+	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+}
+
+static void
+l2_go_st3(struct FsmInst *fi, int event, void *arg)
+{
+	dev_kfree_skb((struct sk_buff *)arg);
+	mISDN_FsmChangeState(fi, ST_L2_3);
+}
+
+static void
+l2_mdl_assign(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+
+	mISDN_FsmChangeState(fi, ST_L2_3);
+	dev_kfree_skb((struct sk_buff *)arg);
+	l2_tei(l2, MDL_ASSIGN_IND, 0);
+}
+
+static void
+l2_queue_ui_assign(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_tail(&l2->ui_queue, skb);
+	mISDN_FsmChangeState(fi, ST_L2_2);
+	l2_tei(l2, MDL_ASSIGN_IND, 0);
+}
+
+static void
+l2_queue_ui(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_tail(&l2->ui_queue, skb);
+}
+
+static void
+tx_ui(struct layer2 *l2)
+{
+	struct sk_buff *skb;
+	u_char header[MAX_L2HEADER_LEN];
+	int i;
+
+	i = sethdraddr(l2, header, CMD);
+	if (test_bit(FLG_LAPD_NET, &l2->flag))
+		header[1] = 0xff; /* tei 127 */
+	header[i++] = UI;
+	while ((skb = skb_dequeue(&l2->ui_queue))) {
+		memcpy(skb_push(skb, i), header, i);
+		enqueue_ui(l2, skb);
+	}
+}
+
+static void
+l2_send_ui(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_tail(&l2->ui_queue, skb);
+	tx_ui(l2);
+}
+
+static void
+l2_got_ui(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_pull(skb, l2headersize(l2, 1));
+/*
+ *		in states 1-3 for broadcast
+ */
+
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_UI_IND, 0);
+	l2up(l2, DL_UNITDATA_IND, skb);
+}
+
+static void
+l2_establish(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	establishlink(fi);
+	test_and_set_bit(FLG_L3_INIT, &l2->flag);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_discard_i_setl3(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->i_queue);
+	test_and_set_bit(FLG_L3_INIT, &l2->flag);
+	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_l3_reestablish(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->i_queue);
+	establishlink(fi);
+	test_and_set_bit(FLG_L3_INIT, &l2->flag);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_release(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_trim(skb, 0);
+	l2up(l2, DL_RELEASE_CNF, skb);
+}
+
+static void
+l2_pend_rel(struct FsmInst *fi, int event, void *arg)
+{
+	struct sk_buff *skb = arg;
+	struct layer2 *l2 = fi->userdata;
+
+	test_and_set_bit(FLG_PEND_REL, &l2->flag);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_disconnect(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_purge(&l2->i_queue);
+	freewin(l2);
+	mISDN_FsmChangeState(fi, ST_L2_6);
+	l2->rc = 0;
+	send_uframe(l2, NULL, DISC | 0x10, CMD);
+	mISDN_FsmDelTimer(&l2->t203, 1);
+	restart_t200(l2, 2);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_start_multi(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb = arg;
+
+	l2->vs = 0;
+	l2->va = 0;
+	l2->vr = 0;
+	l2->sow = 0;
+	clear_exception(l2);
+	send_uframe(l2, NULL, UA | get_PollFlag(l2, skb), RSP);
+	mISDN_FsmChangeState(fi, ST_L2_7);
+	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);
+	skb_trim(skb, 0);
+	l2up(l2, DL_ESTABLISH_IND, skb);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_UP_IND, 0);
+}
+
+static void
+l2_send_UA(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
+}
+
+static void
+l2_send_DM(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	send_uframe(l2, skb, DM | get_PollFlag(l2, skb), RSP);
+}
+
+static void
+l2_restart_multi(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb = arg;
+	int		est = 0;
+
+	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
+
+	l2mgr(l2, MDL_ERROR_IND, (void *) 'F');
+
+	if (l2->vs != l2->va) {
+		skb_queue_purge(&l2->i_queue);
+		est = 1;
+	}
+
+	clear_exception(l2);
+	l2->vs = 0;
+	l2->va = 0;
+	l2->vr = 0;
+	l2->sow = 0;
+	mISDN_FsmChangeState(fi, ST_L2_7);
+	stop_t200(l2, 3);
+	mISDN_FsmRestartTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);
+
+	if (est)
+		l2up_create(l2, DL_ESTABLISH_IND, 0, NULL);
+/*		mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
+ *		    MGR_SHORTSTATUS | INDICATION, SSTATUS_L2_ESTABLISHED,
+ *		    0, NULL, 0);
+ */
+	if (skb_queue_len(&l2->i_queue) && cansend(l2))
+		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+}
+
+static void
+l2_stop_multi(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb = arg;
+
+	mISDN_FsmChangeState(fi, ST_L2_4);
+	mISDN_FsmDelTimer(&l2->t203, 3);
+	stop_t200(l2, 4);
+
+	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
+	skb_queue_purge(&l2->i_queue);
+	freewin(l2);
+	lapb_dl_release_l2l3(l2, DL_RELEASE_IND);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+}
+
+static void
+l2_connected(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb = arg;
+	int pr = -1;
+
+	if (!get_PollFlag(l2, skb)) {
+		l2_mdl_error_ua(fi, event, arg);
+		return;
+	}
+	dev_kfree_skb(skb);
+	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
+		l2_disconnect(fi, event, NULL);
+	if (test_and_clear_bit(FLG_L3_INIT, &l2->flag)) {
+		pr = DL_ESTABLISH_CNF;
+	} else if (l2->vs != l2->va) {
+		skb_queue_purge(&l2->i_queue);
+		pr = DL_ESTABLISH_IND;
+	}
+	stop_t200(l2, 5);
+	l2->vr = 0;
+	l2->vs = 0;
+	l2->va = 0;
+	l2->sow = 0;
+	mISDN_FsmChangeState(fi, ST_L2_7);
+	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 4);
+	if (pr != -1)
+		l2up_create(l2, pr, 0, NULL);
+
+	if (skb_queue_len(&l2->i_queue) && cansend(l2))
+		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_UP_IND, 0);
+}
+
+static void
+l2_released(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (!get_PollFlag(l2, skb)) {
+		l2_mdl_error_ua(fi, event, arg);
+		return;
+	}
+	dev_kfree_skb(skb);
+	stop_t200(l2, 6);
+	lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
+	mISDN_FsmChangeState(fi, ST_L2_4);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+}
+
+static void
+l2_reestablish(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (!get_PollFlagFree(l2, skb)) {
+		establishlink(fi);
+		test_and_set_bit(FLG_L3_INIT, &l2->flag);
+	}
+}
+
+static void
+l2_st5_dm_release(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (get_PollFlagFree(l2, skb)) {
+		stop_t200(l2, 7);
+		if (!test_bit(FLG_L3_INIT, &l2->flag))
+			skb_queue_purge(&l2->i_queue);
+		if (test_bit(FLG_LAPB, &l2->flag))
+			l2down_create(l2, PH_DEACTIVATE_REQ,
+				      l2_newid(l2), 0, NULL);
+		st5_dl_release_l2l3(l2);
+		mISDN_FsmChangeState(fi, ST_L2_4);
+		if (l2->tm)
+			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+	}
+}
+
+static void
+l2_st6_dm_release(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (get_PollFlagFree(l2, skb)) {
+		stop_t200(l2, 8);
+		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
+		mISDN_FsmChangeState(fi, ST_L2_4);
+		if (l2->tm)
+			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+	}
+}
+
+static void
+enquiry_cr(struct layer2 *l2, u_char typ, u_char cr, u_char pf)
+{
+	struct sk_buff *skb;
+	u_char tmp[MAX_L2HEADER_LEN];
+	int i;
+
+	i = sethdraddr(l2, tmp, cr);
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		tmp[i++] = typ;
+		tmp[i++] = (l2->vr << 1) | (pf ? 1 : 0);
+	} else
+		tmp[i++] = (l2->vr << 5) | typ | (pf ? 0x10 : 0);
+	skb = mI_alloc_skb(i, GFP_ATOMIC);
+	if (!skb) {
+		printk(KERN_WARNING "%s: isdnl2 can't alloc sbbuff in %s\n",
+		       mISDNDevName4ch(&l2->ch), __func__);
+		return;
+	}
+	skb_put_data(skb, tmp, i);
+	enqueue_super(l2, skb);
+}
+
+inline void
+enquiry_response(struct layer2 *l2)
+{
+	if (test_bit(FLG_OWN_BUSY, &l2->flag))
+		enquiry_cr(l2, RNR, RSP, 1);
+	else
+		enquiry_cr(l2, RR, RSP, 1);
+	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+}
+
+inline void
+transmit_enquiry(struct layer2 *l2)
+{
+	if (test_bit(FLG_OWN_BUSY, &l2->flag))
+		enquiry_cr(l2, RNR, CMD, 1);
+	else
+		enquiry_cr(l2, RR, CMD, 1);
+	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+	start_t200(l2, 9);
+}
+
+
+static void
+nrerrorrecovery(struct FsmInst *fi)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	l2mgr(l2, MDL_ERROR_IND, (void *) 'J');
+	establishlink(fi);
+	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+}
+
+static void
+invoke_retransmission(struct layer2 *l2, unsigned int nr)
+{
+	u_int	p1;
+
+	if (l2->vs != nr) {
+		while (l2->vs != nr) {
+			(l2->vs)--;
+			if (test_bit(FLG_MOD128, &l2->flag)) {
+				l2->vs %= 128;
+				p1 = (l2->vs - l2->va) % 128;
+			} else {
+				l2->vs %= 8;
+				p1 = (l2->vs - l2->va) % 8;
+			}
+			p1 = (p1 + l2->sow) % l2->window;
+			if (l2->windowar[p1])
+				skb_queue_head(&l2->i_queue, l2->windowar[p1]);
+			else
+				printk(KERN_WARNING
+				       "%s: windowar[%d] is NULL\n",
+				       mISDNDevName4ch(&l2->ch), p1);
+			l2->windowar[p1] = NULL;
+		}
+		mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
+	}
+}
+
+static void
+l2_st7_got_super(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+	int PollFlag, rsp, typ = RR;
+	unsigned int nr;
+
+	rsp = *skb->data & 0x2;
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+
+	skb_pull(skb, l2addrsize(l2));
+	if (IsRNR(skb->data, l2)) {
+		set_peer_busy(l2);
+		typ = RNR;
+	} else
+		clear_peer_busy(l2);
+	if (IsREJ(skb->data, l2))
+		typ = REJ;
+
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		PollFlag = (skb->data[1] & 0x1) == 0x1;
+		nr = skb->data[1] >> 1;
+	} else {
+		PollFlag = (skb->data[0] & 0x10);
+		nr = (skb->data[0] >> 5) & 0x7;
+	}
+	dev_kfree_skb(skb);
+
+	if (PollFlag) {
+		if (rsp)
+			l2mgr(l2, MDL_ERROR_IND, (void *) 'A');
+		else
+			enquiry_response(l2);
+	}
+	if (legalnr(l2, nr)) {
+		if (typ == REJ) {
+			setva(l2, nr);
+			invoke_retransmission(l2, nr);
+			stop_t200(l2, 10);
+			if (mISDN_FsmAddTimer(&l2->t203, l2->T203,
+					      EV_L2_T203, NULL, 6))
+				l2m_debug(&l2->l2m, "Restart T203 ST7 REJ");
+		} else if ((nr == l2->vs) && (typ == RR)) {
+			setva(l2, nr);
+			stop_t200(l2, 11);
+			mISDN_FsmRestartTimer(&l2->t203, l2->T203,
+					      EV_L2_T203, NULL, 7);
+		} else if ((l2->va != nr) || (typ == RNR)) {
+			setva(l2, nr);
+			if (typ != RR)
+				mISDN_FsmDelTimer(&l2->t203, 9);
+			restart_t200(l2, 12);
+		}
+		if (skb_queue_len(&l2->i_queue) && (typ == RR))
+			mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+	} else
+		nrerrorrecovery(fi);
+}
+
+static void
+l2_feed_i_if_reest(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (!test_bit(FLG_L3_INIT, &l2->flag))
+		skb_queue_tail(&l2->i_queue, skb);
+	else
+		dev_kfree_skb(skb);
+}
+
+static void
+l2_feed_i_pull(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_tail(&l2->i_queue, skb);
+	mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+}
+
+static void
+l2_feed_iqueue(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_tail(&l2->i_queue, skb);
+}
+
+static void
+l2_got_iframe(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb = arg;
+	int		PollFlag, i;
+	u_int		ns, nr;
+
+	i = l2addrsize(l2);
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		PollFlag = ((skb->data[i + 1] & 0x1) == 0x1);
+		ns = skb->data[i] >> 1;
+		nr = (skb->data[i + 1] >> 1) & 0x7f;
+	} else {
+		PollFlag = (skb->data[i] & 0x10);
+		ns = (skb->data[i] >> 1) & 0x7;
+		nr = (skb->data[i] >> 5) & 0x7;
+	}
+	if (test_bit(FLG_OWN_BUSY, &l2->flag)) {
+		dev_kfree_skb(skb);
+		if (PollFlag)
+			enquiry_response(l2);
+	} else {
+		if (l2->vr == ns) {
+			l2->vr++;
+			if (test_bit(FLG_MOD128, &l2->flag))
+				l2->vr %= 128;
+			else
+				l2->vr %= 8;
+			test_and_clear_bit(FLG_REJEXC, &l2->flag);
+			if (PollFlag)
+				enquiry_response(l2);
+			else
+				test_and_set_bit(FLG_ACK_PEND, &l2->flag);
+			skb_pull(skb, l2headersize(l2, 0));
+			l2up(l2, DL_DATA_IND, skb);
+		} else {
+			/* n(s)!=v(r) */
+			dev_kfree_skb(skb);
+			if (test_and_set_bit(FLG_REJEXC, &l2->flag)) {
+				if (PollFlag)
+					enquiry_response(l2);
+			} else {
+				enquiry_cr(l2, REJ, RSP, PollFlag);
+				test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+			}
+		}
+	}
+	if (legalnr(l2, nr)) {
+		if (!test_bit(FLG_PEER_BUSY, &l2->flag) &&
+		    (fi->state == ST_L2_7)) {
+			if (nr == l2->vs) {
+				stop_t200(l2, 13);
+				mISDN_FsmRestartTimer(&l2->t203, l2->T203,
+						      EV_L2_T203, NULL, 7);
+			} else if (nr != l2->va)
+				restart_t200(l2, 14);
+		}
+		setva(l2, nr);
+	} else {
+		nrerrorrecovery(fi);
+		return;
+	}
+	if (skb_queue_len(&l2->i_queue) && (fi->state == ST_L2_7))
+		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+	if (test_and_clear_bit(FLG_ACK_PEND, &l2->flag))
+		enquiry_cr(l2, RR, RSP, 0);
+}
+
+static void
+l2_got_tei(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	u_int		info;
+
+	l2->tei = (signed char)(long)arg;
+	set_channel_address(&l2->ch, l2->sapi, l2->tei);
+	info = DL_INFO_L2_CONNECT;
+	l2up_create(l2, DL_INFORMATION_IND, sizeof(info), &info);
+	if (fi->state == ST_L2_3) {
+		establishlink(fi);
+		test_and_set_bit(FLG_L3_INIT, &l2->flag);
+	} else
+		mISDN_FsmChangeState(fi, ST_L2_4);
+	if (skb_queue_len(&l2->ui_queue))
+		tx_ui(l2);
+}
+
+static void
+l2_st5_tout_200(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
+	} else if (l2->rc == l2->N200) {
+		mISDN_FsmChangeState(fi, ST_L2_4);
+		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
+		skb_queue_purge(&l2->i_queue);
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'G');
+		if (test_bit(FLG_LAPB, &l2->flag))
+			l2down_create(l2, PH_DEACTIVATE_REQ,
+				      l2_newid(l2), 0, NULL);
+		st5_dl_release_l2l3(l2);
+		if (l2->tm)
+			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+	} else {
+		l2->rc++;
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
+		send_uframe(l2, NULL, (test_bit(FLG_MOD128, &l2->flag) ?
+				       SABME : SABM) | 0x10, CMD);
+	}
+}
+
+static void
+l2_st6_tout_200(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
+	} else if (l2->rc == l2->N200) {
+		mISDN_FsmChangeState(fi, ST_L2_4);
+		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'H');
+		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
+		if (l2->tm)
+			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+	} else {
+		l2->rc++;
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200,
+				  NULL, 9);
+		send_uframe(l2, NULL, DISC | 0x10, CMD);
+	}
+}
+
+static void
+l2_st7_tout_200(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
+		return;
+	}
+	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
+	l2->rc = 0;
+	mISDN_FsmChangeState(fi, ST_L2_8);
+	transmit_enquiry(l2);
+	l2->rc++;
+}
+
+static void
+l2_st8_tout_200(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
+		return;
+	}
+	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
+	if (l2->rc == l2->N200) {
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'I');
+		establishlink(fi);
+		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+	} else {
+		transmit_enquiry(l2);
+		l2->rc++;
+	}
+}
+
+static void
+l2_st7_tout_203(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	if (test_bit(FLG_LAPD, &l2->flag) &&
+	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
+		mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 9);
+		return;
+	}
+	mISDN_FsmChangeState(fi, ST_L2_8);
+	transmit_enquiry(l2);
+	l2->rc = 0;
+}
+
+static void
+l2_pull_iqueue(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2	*l2 = fi->userdata;
+	struct sk_buff	*skb, *nskb;
+	u_char		header[MAX_L2HEADER_LEN];
+	u_int		i, p1;
+
+	if (!cansend(l2))
+		return;
+
+	skb = skb_dequeue(&l2->i_queue);
+	if (!skb)
+		return;
+	i = sethdraddr(l2, header, CMD);
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		header[i++] = l2->vs << 1;
+		header[i++] = l2->vr << 1;
+	} else
+		header[i++] = (l2->vr << 5) | (l2->vs << 1);
+	nskb = skb_realloc_headroom(skb, i);
+	if (!nskb) {
+		printk(KERN_WARNING "%s: no headroom(%d) copy for IFrame\n",
+		       mISDNDevName4ch(&l2->ch), i);
+		skb_queue_head(&l2->i_queue, skb);
+		return;
+	}
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		p1 = (l2->vs - l2->va) % 128;
+		l2->vs = (l2->vs + 1) % 128;
+	} else {
+		p1 = (l2->vs - l2->va) % 8;
+		l2->vs = (l2->vs + 1) % 8;
+	}
+	p1 = (p1 + l2->sow) % l2->window;
+	if (l2->windowar[p1]) {
+		printk(KERN_WARNING "%s: l2 try overwrite ack queue entry %d\n",
+		       mISDNDevName4ch(&l2->ch), p1);
+		dev_kfree_skb(l2->windowar[p1]);
+	}
+	l2->windowar[p1] = skb;
+	memcpy(skb_push(nskb, i), header, i);
+	l2down(l2, PH_DATA_REQ, l2_newid(l2), nskb);
+	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+	if (!test_and_set_bit(FLG_T200_RUN, &l2->flag)) {
+		mISDN_FsmDelTimer(&l2->t203, 13);
+		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 11);
+	}
+}
+
+static void
+l2_st8_got_super(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+	int PollFlag, rsp, rnr = 0;
+	unsigned int nr;
+
+	rsp = *skb->data & 0x2;
+	if (test_bit(FLG_ORIG, &l2->flag))
+		rsp = !rsp;
+
+	skb_pull(skb, l2addrsize(l2));
+
+	if (IsRNR(skb->data, l2)) {
+		set_peer_busy(l2);
+		rnr = 1;
+	} else
+		clear_peer_busy(l2);
+
+	if (test_bit(FLG_MOD128, &l2->flag)) {
+		PollFlag = (skb->data[1] & 0x1) == 0x1;
+		nr = skb->data[1] >> 1;
+	} else {
+		PollFlag = (skb->data[0] & 0x10);
+		nr = (skb->data[0] >> 5) & 0x7;
+	}
+	dev_kfree_skb(skb);
+	if (rsp && PollFlag) {
+		if (legalnr(l2, nr)) {
+			if (rnr) {
+				restart_t200(l2, 15);
+			} else {
+				stop_t200(l2, 16);
+				mISDN_FsmAddTimer(&l2->t203, l2->T203,
+						  EV_L2_T203, NULL, 5);
+				setva(l2, nr);
+			}
+			invoke_retransmission(l2, nr);
+			mISDN_FsmChangeState(fi, ST_L2_7);
+			if (skb_queue_len(&l2->i_queue) && cansend(l2))
+				mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
+		} else
+			nrerrorrecovery(fi);
+	} else {
+		if (!rsp && PollFlag)
+			enquiry_response(l2);
+		if (legalnr(l2, nr))
+			setva(l2, nr);
+		else
+			nrerrorrecovery(fi);
+	}
+}
+
+static void
+l2_got_FRMR(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_pull(skb, l2addrsize(l2) + 1);
+
+	if (!(skb->data[0] & 1) || ((skb->data[0] & 3) == 1) || /* I or S */
+	    (IsUA(skb->data) && (fi->state == ST_L2_7))) {
+		l2mgr(l2, MDL_ERROR_IND, (void *) 'K');
+		establishlink(fi);
+		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+	}
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_st24_tei_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->ui_queue);
+	l2->tei = GROUP_TEI;
+	mISDN_FsmChangeState(fi, ST_L2_1);
+}
+
+static void
+l2_st3_tei_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->ui_queue);
+	l2->tei = GROUP_TEI;
+	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
+	mISDN_FsmChangeState(fi, ST_L2_1);
+}
+
+static void
+l2_st5_tei_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	freewin(l2);
+	l2->tei = GROUP_TEI;
+	stop_t200(l2, 17);
+	st5_dl_release_l2l3(l2);
+	mISDN_FsmChangeState(fi, ST_L2_1);
+}
+
+static void
+l2_st6_tei_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->ui_queue);
+	l2->tei = GROUP_TEI;
+	stop_t200(l2, 18);
+	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
+	mISDN_FsmChangeState(fi, ST_L2_1);
+}
+
+static void
+l2_tei_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	freewin(l2);
+	l2->tei = GROUP_TEI;
+	stop_t200(l2, 17);
+	mISDN_FsmDelTimer(&l2->t203, 19);
+	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
+/*	mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
+ *		MGR_SHORTSTATUS_IND, SSTATUS_L2_RELEASED,
+ *		0, NULL, 0);
+ */
+	mISDN_FsmChangeState(fi, ST_L2_1);
+}
+
+static void
+l2_st14_persistent_da(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
+		l2up(l2, DL_RELEASE_IND, skb);
+	else
+		dev_kfree_skb(skb);
+}
+
+static void
+l2_st5_persistent_da(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	freewin(l2);
+	stop_t200(l2, 19);
+	st5_dl_release_l2l3(l2);
+	mISDN_FsmChangeState(fi, ST_L2_4);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_st6_persistent_da(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_purge(&l2->ui_queue);
+	stop_t200(l2, 20);
+	l2up(l2, DL_RELEASE_CNF, skb);
+	mISDN_FsmChangeState(fi, ST_L2_4);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+}
+
+static void
+l2_persistent_da(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	freewin(l2);
+	stop_t200(l2, 19);
+	mISDN_FsmDelTimer(&l2->t203, 19);
+	l2up(l2, DL_RELEASE_IND, skb);
+	mISDN_FsmChangeState(fi, ST_L2_4);
+	if (l2->tm)
+		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
+}
+
+static void
+l2_set_own_busy(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (!test_and_set_bit(FLG_OWN_BUSY, &l2->flag)) {
+		enquiry_cr(l2, RNR, RSP, 0);
+		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+	}
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_clear_own_busy(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+	struct sk_buff *skb = arg;
+
+	if (!test_and_clear_bit(FLG_OWN_BUSY, &l2->flag)) {
+		enquiry_cr(l2, RR, RSP, 0);
+		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
+	}
+	dev_kfree_skb(skb);
+}
+
+static void
+l2_frame_error(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	l2mgr(l2, MDL_ERROR_IND, arg);
+}
+
+static void
+l2_frame_error_reest(struct FsmInst *fi, int event, void *arg)
+{
+	struct layer2 *l2 = fi->userdata;
+
+	l2mgr(l2, MDL_ERROR_IND, arg);
+	establishlink(fi);
+	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
+}
+
+static struct FsmNode L2FnList[] =
+{
+	{ST_L2_1, EV_L2_DL_ESTABLISH_REQ, l2_mdl_assign},
+	{ST_L2_2, EV_L2_DL_ESTABLISH_REQ, l2_go_st3},
+	{ST_L2_4, EV_L2_DL_ESTABLISH_REQ, l2_establish},
+	{ST_L2_5, EV_L2_DL_ESTABLISH_REQ, l2_discard_i_setl3},
+	{ST_L2_7, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
+	{ST_L2_8, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
+	{ST_L2_4, EV_L2_DL_RELEASE_REQ, l2_release},
+	{ST_L2_5, EV_L2_DL_RELEASE_REQ, l2_pend_rel},
+	{ST_L2_7, EV_L2_DL_RELEASE_REQ, l2_disconnect},
+	{ST_L2_8, EV_L2_DL_RELEASE_REQ, l2_disconnect},
+	{ST_L2_5, EV_L2_DL_DATA, l2_feed_i_if_reest},
+	{ST_L2_7, EV_L2_DL_DATA, l2_feed_i_pull},
+	{ST_L2_8, EV_L2_DL_DATA, l2_feed_iqueue},
+	{ST_L2_1, EV_L2_DL_UNITDATA, l2_queue_ui_assign},
+	{ST_L2_2, EV_L2_DL_UNITDATA, l2_queue_ui},
+	{ST_L2_3, EV_L2_DL_UNITDATA, l2_queue_ui},
+	{ST_L2_4, EV_L2_DL_UNITDATA, l2_send_ui},
+	{ST_L2_5, EV_L2_DL_UNITDATA, l2_send_ui},
+	{ST_L2_6, EV_L2_DL_UNITDATA, l2_send_ui},
+	{ST_L2_7, EV_L2_DL_UNITDATA, l2_send_ui},
+	{ST_L2_8, EV_L2_DL_UNITDATA, l2_send_ui},
+	{ST_L2_1, EV_L2_MDL_ASSIGN, l2_got_tei},
+	{ST_L2_2, EV_L2_MDL_ASSIGN, l2_got_tei},
+	{ST_L2_3, EV_L2_MDL_ASSIGN, l2_got_tei},
+	{ST_L2_2, EV_L2_MDL_ERROR, l2_st24_tei_remove},
+	{ST_L2_3, EV_L2_MDL_ERROR, l2_st3_tei_remove},
+	{ST_L2_4, EV_L2_MDL_REMOVE, l2_st24_tei_remove},
+	{ST_L2_5, EV_L2_MDL_REMOVE, l2_st5_tei_remove},
+	{ST_L2_6, EV_L2_MDL_REMOVE, l2_st6_tei_remove},
+	{ST_L2_7, EV_L2_MDL_REMOVE, l2_tei_remove},
+	{ST_L2_8, EV_L2_MDL_REMOVE, l2_tei_remove},
+	{ST_L2_4, EV_L2_SABME, l2_start_multi},
+	{ST_L2_5, EV_L2_SABME, l2_send_UA},
+	{ST_L2_6, EV_L2_SABME, l2_send_DM},
+	{ST_L2_7, EV_L2_SABME, l2_restart_multi},
+	{ST_L2_8, EV_L2_SABME, l2_restart_multi},
+	{ST_L2_4, EV_L2_DISC, l2_send_DM},
+	{ST_L2_5, EV_L2_DISC, l2_send_DM},
+	{ST_L2_6, EV_L2_DISC, l2_send_UA},
+	{ST_L2_7, EV_L2_DISC, l2_stop_multi},
+	{ST_L2_8, EV_L2_DISC, l2_stop_multi},
+	{ST_L2_4, EV_L2_UA, l2_mdl_error_ua},
+	{ST_L2_5, EV_L2_UA, l2_connected},
+	{ST_L2_6, EV_L2_UA, l2_released},
+	{ST_L2_7, EV_L2_UA, l2_mdl_error_ua},
+	{ST_L2_8, EV_L2_UA, l2_mdl_error_ua},
+	{ST_L2_4, EV_L2_DM, l2_reestablish},
+	{ST_L2_5, EV_L2_DM, l2_st5_dm_release},
+	{ST_L2_6, EV_L2_DM, l2_st6_dm_release},
+	{ST_L2_7, EV_L2_DM, l2_mdl_error_dm},
+	{ST_L2_8, EV_L2_DM, l2_st8_mdl_error_dm},
+	{ST_L2_1, EV_L2_UI, l2_got_ui},
+	{ST_L2_2, EV_L2_UI, l2_got_ui},
+	{ST_L2_3, EV_L2_UI, l2_got_ui},
+	{ST_L2_4, EV_L2_UI, l2_got_ui},
+	{ST_L2_5, EV_L2_UI, l2_got_ui},
+	{ST_L2_6, EV_L2_UI, l2_got_ui},
+	{ST_L2_7, EV_L2_UI, l2_got_ui},
+	{ST_L2_8, EV_L2_UI, l2_got_ui},
+	{ST_L2_7, EV_L2_FRMR, l2_got_FRMR},
+	{ST_L2_8, EV_L2_FRMR, l2_got_FRMR},
+	{ST_L2_7, EV_L2_SUPER, l2_st7_got_super},
+	{ST_L2_8, EV_L2_SUPER, l2_st8_got_super},
+	{ST_L2_7, EV_L2_I, l2_got_iframe},
+	{ST_L2_8, EV_L2_I, l2_got_iframe},
+	{ST_L2_5, EV_L2_T200, l2_timeout},
+	{ST_L2_6, EV_L2_T200, l2_timeout},
+	{ST_L2_7, EV_L2_T200, l2_timeout},
+	{ST_L2_8, EV_L2_T200, l2_timeout},
+	{ST_L2_7, EV_L2_T203, l2_timeout},
+	{ST_L2_5, EV_L2_T200I, l2_st5_tout_200},
+	{ST_L2_6, EV_L2_T200I, l2_st6_tout_200},
+	{ST_L2_7, EV_L2_T200I, l2_st7_tout_200},
+	{ST_L2_8, EV_L2_T200I, l2_st8_tout_200},
+	{ST_L2_7, EV_L2_T203I, l2_st7_tout_203},
+	{ST_L2_7, EV_L2_ACK_PULL, l2_pull_iqueue},
+	{ST_L2_7, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
+	{ST_L2_8, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
+	{ST_L2_7, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
+	{ST_L2_8, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
+	{ST_L2_4, EV_L2_FRAME_ERROR, l2_frame_error},
+	{ST_L2_5, EV_L2_FRAME_ERROR, l2_frame_error},
+	{ST_L2_6, EV_L2_FRAME_ERROR, l2_frame_error},
+	{ST_L2_7, EV_L2_FRAME_ERROR, l2_frame_error_reest},
+	{ST_L2_8, EV_L2_FRAME_ERROR, l2_frame_error_reest},
+	{ST_L2_1, EV_L1_DEACTIVATE, l2_st14_persistent_da},
+	{ST_L2_2, EV_L1_DEACTIVATE, l2_st24_tei_remove},
+	{ST_L2_3, EV_L1_DEACTIVATE, l2_st3_tei_remove},
+	{ST_L2_4, EV_L1_DEACTIVATE, l2_st14_persistent_da},
+	{ST_L2_5, EV_L1_DEACTIVATE, l2_st5_persistent_da},
+	{ST_L2_6, EV_L1_DEACTIVATE, l2_st6_persistent_da},
+	{ST_L2_7, EV_L1_DEACTIVATE, l2_persistent_da},
+	{ST_L2_8, EV_L1_DEACTIVATE, l2_persistent_da},
+};
+
+static int
+ph_data_indication(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb)
+{
+	u_char	*datap = skb->data;
+	int	ret = -EINVAL;
+	int	psapi, ptei;
+	u_int	l;
+	int	c = 0;
+
+	l = l2addrsize(l2);
+	if (skb->len <= l) {
+		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *) 'N');
+		return ret;
+	}
+	if (test_bit(FLG_LAPD, &l2->flag)) { /* Maybe not needed */
+		psapi = *datap++;
+		ptei = *datap++;
+		if ((psapi & 1) || !(ptei & 1)) {
+			printk(KERN_WARNING
+			       "%s l2 D-channel frame wrong EA0/EA1\n",
+			       mISDNDevName4ch(&l2->ch));
+			return ret;
+		}
+		psapi >>= 2;
+		ptei >>= 1;
+		if (psapi != l2->sapi) {
+			/* not our business */
+			if (*debug & DEBUG_L2)
+				printk(KERN_DEBUG "%s: sapi %d/%d mismatch\n",
+				       mISDNDevName4ch(&l2->ch), psapi,
+				       l2->sapi);
+			dev_kfree_skb(skb);
+			return 0;
+		}
+		if ((ptei != l2->tei) && (ptei != GROUP_TEI)) {
+			/* not our business */
+			if (*debug & DEBUG_L2)
+				printk(KERN_DEBUG "%s: tei %d/%d mismatch\n",
+				       mISDNDevName4ch(&l2->ch), ptei, l2->tei);
+			dev_kfree_skb(skb);
+			return 0;
+		}
+	} else
+		datap += l;
+	if (!(*datap & 1)) {	/* I-Frame */
+		c = iframe_error(l2, skb);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_I, skb);
+	} else if (IsSFrame(datap, l2)) {	/* S-Frame */
+		c = super_error(l2, skb);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SUPER, skb);
+	} else if (IsUI(datap)) {
+		c = UI_error(l2, skb);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UI, skb);
+	} else if (IsSABME(datap, l2)) {
+		c = unnum_error(l2, skb, CMD);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SABME, skb);
+	} else if (IsUA(datap)) {
+		c = unnum_error(l2, skb, RSP);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UA, skb);
+	} else if (IsDISC(datap)) {
+		c = unnum_error(l2, skb, CMD);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DISC, skb);
+	} else if (IsDM(datap)) {
+		c = unnum_error(l2, skb, RSP);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DM, skb);
+	} else if (IsFRMR(datap)) {
+		c = FRMR_error(l2, skb);
+		if (!c)
+			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_FRMR, skb);
+	} else
+		c = 'L';
+	if (c) {
+		printk(KERN_WARNING "%s:l2 D-channel frame error %c\n",
+		       mISDNDevName4ch(&l2->ch), c);
+		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *)(long)c);
+	}
+	return ret;
+}
+
+static int
+l2_send(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct layer2		*l2 = container_of(ch, struct layer2, ch);
+	struct mISDNhead	*hh =  mISDN_HEAD_P(skb);
+	int			ret = -EINVAL;
+
+	if (*debug & DEBUG_L2_RECV)
+		printk(KERN_DEBUG "%s: %s prim(%x) id(%x) sapi(%d) tei(%d)\n",
+		       __func__, mISDNDevName4ch(&l2->ch), hh->prim, hh->id,
+		       l2->sapi, l2->tei);
+	if (hh->prim == DL_INTERN_MSG) {
+		struct mISDNhead *chh = hh + 1; /* saved copy */
+
+		*hh = *chh;
+		if (*debug & DEBUG_L2_RECV)
+			printk(KERN_DEBUG "%s: prim(%x) id(%x) internal msg\n",
+				mISDNDevName4ch(&l2->ch), hh->prim, hh->id);
+	}
+	switch (hh->prim) {
+	case PH_DATA_IND:
+		ret = ph_data_indication(l2, hh, skb);
+		break;
+	case PH_DATA_CNF:
+		ret = ph_data_confirm(l2, hh, skb);
+		break;
+	case PH_ACTIVATE_IND:
+		test_and_set_bit(FLG_L1_ACTIV, &l2->flag);
+		l2up_create(l2, MPH_ACTIVATE_IND, 0, NULL);
+		if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
+			ret = mISDN_FsmEvent(&l2->l2m,
+					     EV_L2_DL_ESTABLISH_REQ, skb);
+		break;
+	case PH_DEACTIVATE_IND:
+		test_and_clear_bit(FLG_L1_ACTIV, &l2->flag);
+		l2up_create(l2, MPH_DEACTIVATE_IND, 0, NULL);
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L1_DEACTIVATE, skb);
+		break;
+	case MPH_INFORMATION_IND:
+		if (!l2->up)
+			break;
+		ret = l2->up->send(l2->up, skb);
+		break;
+	case DL_DATA_REQ:
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_DATA, skb);
+		break;
+	case DL_UNITDATA_REQ:
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_UNITDATA, skb);
+		break;
+	case DL_ESTABLISH_REQ:
+		if (test_bit(FLG_LAPB, &l2->flag))
+			test_and_set_bit(FLG_ORIG, &l2->flag);
+		if (test_bit(FLG_L1_ACTIV, &l2->flag)) {
+			if (test_bit(FLG_LAPD, &l2->flag) ||
+			    test_bit(FLG_ORIG, &l2->flag))
+				ret = mISDN_FsmEvent(&l2->l2m,
+						     EV_L2_DL_ESTABLISH_REQ, skb);
+		} else {
+			if (test_bit(FLG_LAPD, &l2->flag) ||
+			    test_bit(FLG_ORIG, &l2->flag)) {
+				test_and_set_bit(FLG_ESTAB_PEND,
+						 &l2->flag);
+			}
+			ret = l2down(l2, PH_ACTIVATE_REQ, l2_newid(l2),
+				     skb);
+		}
+		break;
+	case DL_RELEASE_REQ:
+		if (test_bit(FLG_LAPB, &l2->flag))
+			l2down_create(l2, PH_DEACTIVATE_REQ,
+				      l2_newid(l2), 0, NULL);
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_RELEASE_REQ,
+				     skb);
+		break;
+	case DL_TIMER200_IND:
+		mISDN_FsmEvent(&l2->l2m, EV_L2_T200I, NULL);
+		break;
+	case DL_TIMER203_IND:
+		mISDN_FsmEvent(&l2->l2m, EV_L2_T203I, NULL);
+		break;
+	default:
+		if (*debug & DEBUG_L2)
+			l2m_debug(&l2->l2m, "l2 unknown pr %04x",
+				  hh->prim);
+	}
+	if (ret) {
+		dev_kfree_skb(skb);
+		ret = 0;
+	}
+	return ret;
+}
+
+int
+tei_l2(struct layer2 *l2, u_int cmd, u_long arg)
+{
+	int		ret = -EINVAL;
+
+	if (*debug & DEBUG_L2_TEI)
+		printk(KERN_DEBUG "%s: cmd(%x) in %s\n",
+		       mISDNDevName4ch(&l2->ch), cmd, __func__);
+	switch (cmd) {
+	case (MDL_ASSIGN_REQ):
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ASSIGN, (void *)arg);
+		break;
+	case (MDL_REMOVE_REQ):
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_REMOVE, NULL);
+		break;
+	case (MDL_ERROR_IND):
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
+		break;
+	case (MDL_ERROR_RSP):
+		/* ETS 300-125 5.3.2.1 Test: TC13010 */
+		printk(KERN_NOTICE "%s: MDL_ERROR|REQ (tei_l2)\n",
+		       mISDNDevName4ch(&l2->ch));
+		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
+		break;
+	}
+	return ret;
+}
+
+static void
+release_l2(struct layer2 *l2)
+{
+	mISDN_FsmDelTimer(&l2->t200, 21);
+	mISDN_FsmDelTimer(&l2->t203, 16);
+	skb_queue_purge(&l2->i_queue);
+	skb_queue_purge(&l2->ui_queue);
+	skb_queue_purge(&l2->down_queue);
+	ReleaseWin(l2);
+	if (test_bit(FLG_LAPD, &l2->flag)) {
+		TEIrelease(l2);
+		if (l2->ch.st)
+			l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D,
+					       CLOSE_CHANNEL, NULL);
+	}
+	kfree(l2);
+}
+
+static int
+l2_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct layer2		*l2 = container_of(ch, struct layer2, ch);
+	u_int			info;
+
+	if (*debug & DEBUG_L2_CTRL)
+		printk(KERN_DEBUG "%s: %s cmd(%x)\n",
+		       mISDNDevName4ch(ch), __func__, cmd);
+
+	switch (cmd) {
+	case OPEN_CHANNEL:
+		if (test_bit(FLG_LAPD, &l2->flag)) {
+			set_channel_address(&l2->ch, l2->sapi, l2->tei);
+			info = DL_INFO_L2_CONNECT;
+			l2up_create(l2, DL_INFORMATION_IND,
+				    sizeof(info), &info);
+		}
+		break;
+	case CLOSE_CHANNEL:
+		if (l2->ch.peer)
+			l2->ch.peer->ctrl(l2->ch.peer, CLOSE_CHANNEL, NULL);
+		release_l2(l2);
+		break;
+	}
+	return 0;
+}
+
+struct layer2 *
+create_l2(struct mISDNchannel *ch, u_int protocol, u_long options, int tei,
+	  int sapi)
+{
+	struct layer2		*l2;
+	struct channel_req	rq;
+
+	l2 = kzalloc(sizeof(struct layer2), GFP_KERNEL);
+	if (!l2) {
+		printk(KERN_ERR "kzalloc layer2 failed\n");
+		return NULL;
+	}
+	l2->next_id = 1;
+	l2->down_id = MISDN_ID_NONE;
+	l2->up = ch;
+	l2->ch.st = ch->st;
+	l2->ch.send = l2_send;
+	l2->ch.ctrl = l2_ctrl;
+	switch (protocol) {
+	case ISDN_P_LAPD_NT:
+		test_and_set_bit(FLG_LAPD, &l2->flag);
+		test_and_set_bit(FLG_LAPD_NET, &l2->flag);
+		test_and_set_bit(FLG_MOD128, &l2->flag);
+		l2->sapi = sapi;
+		l2->maxlen = MAX_DFRAME_LEN;
+		if (test_bit(OPTION_L2_PMX, &options))
+			l2->window = 7;
+		else
+			l2->window = 1;
+		if (test_bit(OPTION_L2_PTP, &options))
+			test_and_set_bit(FLG_PTP, &l2->flag);
+		if (test_bit(OPTION_L2_FIXEDTEI, &options))
+			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
+		l2->tei = tei;
+		l2->T200 = 1000;
+		l2->N200 = 3;
+		l2->T203 = 10000;
+		if (test_bit(OPTION_L2_PMX, &options))
+			rq.protocol = ISDN_P_NT_E1;
+		else
+			rq.protocol = ISDN_P_NT_S0;
+		rq.adr.channel = 0;
+		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
+		break;
+	case ISDN_P_LAPD_TE:
+		test_and_set_bit(FLG_LAPD, &l2->flag);
+		test_and_set_bit(FLG_MOD128, &l2->flag);
+		test_and_set_bit(FLG_ORIG, &l2->flag);
+		l2->sapi = sapi;
+		l2->maxlen = MAX_DFRAME_LEN;
+		if (test_bit(OPTION_L2_PMX, &options))
+			l2->window = 7;
+		else
+			l2->window = 1;
+		if (test_bit(OPTION_L2_PTP, &options))
+			test_and_set_bit(FLG_PTP, &l2->flag);
+		if (test_bit(OPTION_L2_FIXEDTEI, &options))
+			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
+		l2->tei = tei;
+		l2->T200 = 1000;
+		l2->N200 = 3;
+		l2->T203 = 10000;
+		if (test_bit(OPTION_L2_PMX, &options))
+			rq.protocol = ISDN_P_TE_E1;
+		else
+			rq.protocol = ISDN_P_TE_S0;
+		rq.adr.channel = 0;
+		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
+		break;
+	case ISDN_P_B_X75SLP:
+		test_and_set_bit(FLG_LAPB, &l2->flag);
+		l2->window = 7;
+		l2->maxlen = MAX_DATA_SIZE;
+		l2->T200 = 1000;
+		l2->N200 = 4;
+		l2->T203 = 5000;
+		l2->addr.A = 3;
+		l2->addr.B = 1;
+		break;
+	default:
+		printk(KERN_ERR "layer2 create failed prt %x\n",
+		       protocol);
+		kfree(l2);
+		return NULL;
+	}
+	skb_queue_head_init(&l2->i_queue);
+	skb_queue_head_init(&l2->ui_queue);
+	skb_queue_head_init(&l2->down_queue);
+	skb_queue_head_init(&l2->tmp_queue);
+	InitWin(l2);
+	l2->l2m.fsm = &l2fsm;
+	if (test_bit(FLG_LAPB, &l2->flag) ||
+	    test_bit(FLG_FIXED_TEI, &l2->flag) ||
+	    test_bit(FLG_LAPD_NET, &l2->flag))
+		l2->l2m.state = ST_L2_4;
+	else
+		l2->l2m.state = ST_L2_1;
+	l2->l2m.debug = *debug;
+	l2->l2m.userdata = l2;
+	l2->l2m.userint = 0;
+	l2->l2m.printdebug = l2m_debug;
+
+	mISDN_FsmInitTimer(&l2->l2m, &l2->t200);
+	mISDN_FsmInitTimer(&l2->l2m, &l2->t203);
+	return l2;
+}
+
+static int
+x75create(struct channel_req *crq)
+{
+	struct layer2	*l2;
+
+	if (crq->protocol != ISDN_P_B_X75SLP)
+		return -EPROTONOSUPPORT;
+	l2 = create_l2(crq->ch, crq->protocol, 0, 0, 0);
+	if (!l2)
+		return -ENOMEM;
+	crq->ch = &l2->ch;
+	crq->protocol = ISDN_P_B_HDLC;
+	return 0;
+}
+
+static struct Bprotocol X75SLP = {
+	.Bprotocols = (1 << (ISDN_P_B_X75SLP & ISDN_P_B_MASK)),
+	.name = "X75SLP",
+	.create = x75create
+};
+
+int
+Isdnl2_Init(u_int *deb)
+{
+	int res;
+	debug = deb;
+	mISDN_register_Bprotocol(&X75SLP);
+	l2fsm.state_count = L2_STATE_COUNT;
+	l2fsm.event_count = L2_EVENT_COUNT;
+	l2fsm.strEvent = strL2Event;
+	l2fsm.strState = strL2State;
+	res = mISDN_FsmNew(&l2fsm, L2FnList, ARRAY_SIZE(L2FnList));
+	if (res)
+		goto error;
+	res = TEIInit(deb);
+	if (res)
+		goto error_fsm;
+	return 0;
+
+error_fsm:
+	mISDN_FsmFree(&l2fsm);
+error:
+	mISDN_unregister_Bprotocol(&X75SLP);
+	return res;
+}
+
+void
+Isdnl2_cleanup(void)
+{
+	mISDN_unregister_Bprotocol(&X75SLP);
+	TEIFree();
+	mISDN_FsmFree(&l2fsm);
+}
diff --git a/drivers/isdn/mISDN/layer2.h b/drivers/isdn/mISDN/layer2.h
new file mode 100644
index 000000000..c466fd94a
--- /dev/null
+++ b/drivers/isdn/mISDN/layer2.h
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Layer 2 defines
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/mISDNif.h>
+#include <linux/skbuff.h>
+#include "fsm.h"
+
+#define MAX_WINDOW	8
+
+struct manager {
+	struct mISDNchannel	ch;
+	struct mISDNchannel	bcast;
+	u_long			options;
+	struct list_head	layer2;
+	rwlock_t		lock;
+	struct FsmInst		deact;
+	struct FsmTimer		datimer;
+	struct sk_buff_head	sendq;
+	struct mISDNchannel	*up;
+	u_int			nextid;
+	u_int			lastid;
+};
+
+struct teimgr {
+	int			ri;
+	int			rcnt;
+	struct FsmInst		tei_m;
+	struct FsmTimer		timer;
+	int			tval, nval;
+	struct layer2		*l2;
+	struct manager		*mgr;
+};
+
+struct laddr {
+	u_char	A;
+	u_char	B;
+};
+
+struct layer2 {
+	struct list_head	list;
+	struct mISDNchannel	ch;
+	u_long			flag;
+	int			id;
+	struct mISDNchannel	*up;
+	signed char		sapi;
+	signed char		tei;
+	struct laddr		addr;
+	u_int			maxlen;
+	struct teimgr		*tm;
+	u_int			vs, va, vr;
+	int			rc;
+	u_int			window;
+	u_int			sow;
+	struct FsmInst		l2m;
+	struct FsmTimer		t200, t203;
+	int			T200, N200, T203;
+	u_int			next_id;
+	u_int			down_id;
+	struct sk_buff		*windowar[MAX_WINDOW];
+	struct sk_buff_head	i_queue;
+	struct sk_buff_head	ui_queue;
+	struct sk_buff_head	down_queue;
+	struct sk_buff_head	tmp_queue;
+};
+
+enum {
+	ST_L2_1,
+	ST_L2_2,
+	ST_L2_3,
+	ST_L2_4,
+	ST_L2_5,
+	ST_L2_6,
+	ST_L2_7,
+	ST_L2_8,
+};
+
+#define L2_STATE_COUNT (ST_L2_8 + 1)
+
+extern struct layer2	*create_l2(struct mISDNchannel *, u_int,
+				   u_long, int, int);
+extern int		tei_l2(struct layer2 *, u_int, u_long arg);
+
+
+/* from tei.c */
+extern int		l2_tei(struct layer2 *, u_int, u_long arg);
+extern void		TEIrelease(struct layer2 *);
+extern int		TEIInit(u_int *);
+extern void		TEIFree(void);
+
+#define MAX_L2HEADER_LEN 4
+
+#define RR	0x01
+#define RNR	0x05
+#define REJ	0x09
+#define SABME	0x6f
+#define SABM	0x2f
+#define DM	0x0f
+#define UI	0x03
+#define DISC	0x43
+#define UA	0x63
+#define FRMR	0x87
+#define XID	0xaf
+
+#define CMD	0
+#define RSP	1
+
+#define LC_FLUSH_WAIT 1
+
+#define FLG_LAPB	0
+#define FLG_LAPD	1
+#define FLG_ORIG	2
+#define FLG_MOD128	3
+#define FLG_PEND_REL	4
+#define FLG_L3_INIT	5
+#define FLG_T200_RUN	6
+#define FLG_ACK_PEND	7
+#define FLG_REJEXC	8
+#define FLG_OWN_BUSY	9
+#define FLG_PEER_BUSY	10
+#define FLG_DCHAN_BUSY	11
+#define FLG_L1_ACTIV	12
+#define FLG_ESTAB_PEND	13
+#define FLG_PTP		14
+#define FLG_FIXED_TEI	15
+#define FLG_L2BLOCK	16
+#define FLG_L1_NOTREADY	17
+#define FLG_LAPD_NET	18
diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
new file mode 100644
index 000000000..2776ca5fc
--- /dev/null
+++ b/drivers/isdn/mISDN/socket.c
@@ -0,0 +1,825 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/mISDNif.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include "core.h"
+
+static u_int	*debug;
+
+static struct proto mISDN_proto = {
+	.name		= "misdn",
+	.owner		= THIS_MODULE,
+	.obj_size	= sizeof(struct mISDN_sock)
+};
+
+#define _pms(sk)	((struct mISDN_sock *)sk)
+
+static struct mISDN_sock_list	data_sockets = {
+	.lock = __RW_LOCK_UNLOCKED(data_sockets.lock)
+};
+
+static struct mISDN_sock_list	base_sockets = {
+	.lock = __RW_LOCK_UNLOCKED(base_sockets.lock)
+};
+
+#define L2_HEADER_LEN	4
+
+static inline struct sk_buff *
+_l2_alloc_skb(unsigned int len, gfp_t gfp_mask)
+{
+	struct sk_buff  *skb;
+
+	skb = alloc_skb(len + L2_HEADER_LEN, gfp_mask);
+	if (likely(skb))
+		skb_reserve(skb, L2_HEADER_LEN);
+	return skb;
+}
+
+static void
+mISDN_sock_link(struct mISDN_sock_list *l, struct sock *sk)
+{
+	write_lock_bh(&l->lock);
+	sk_add_node(sk, &l->head);
+	write_unlock_bh(&l->lock);
+}
+
+static void mISDN_sock_unlink(struct mISDN_sock_list *l, struct sock *sk)
+{
+	write_lock_bh(&l->lock);
+	sk_del_node_init(sk);
+	write_unlock_bh(&l->lock);
+}
+
+static int
+mISDN_send(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct mISDN_sock *msk;
+	int	err;
+
+	msk = container_of(ch, struct mISDN_sock, ch);
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s len %d %p\n", __func__, skb->len, skb);
+	if (msk->sk.sk_state == MISDN_CLOSED)
+		return -EUNATCH;
+	__net_timestamp(skb);
+	err = sock_queue_rcv_skb(&msk->sk, skb);
+	if (err)
+		printk(KERN_WARNING "%s: error %d\n", __func__, err);
+	return err;
+}
+
+static int
+mISDN_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct mISDN_sock *msk;
+
+	msk = container_of(ch, struct mISDN_sock, ch);
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s(%p, %x, %p)\n", __func__, ch, cmd, arg);
+	switch (cmd) {
+	case CLOSE_CHANNEL:
+		msk->sk.sk_state = MISDN_CLOSED;
+		break;
+	}
+	return 0;
+}
+
+static inline void
+mISDN_sock_cmsg(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
+{
+	struct __kernel_old_timeval	tv;
+
+	if (_pms(sk)->cmask & MISDN_TIME_STAMP) {
+		skb_get_timestamp(skb, &tv);
+		put_cmsg(msg, SOL_MISDN, MISDN_TIME_STAMP, sizeof(tv), &tv);
+	}
+}
+
+static int
+mISDN_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
+		   int flags)
+{
+	struct sk_buff		*skb;
+	struct sock		*sk = sock->sk;
+
+	int		copied, err;
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s: len %d, flags %x ch.nr %d, proto %x\n",
+		       __func__, (int)len, flags, _pms(sk)->ch.nr,
+		       sk->sk_protocol);
+	if (flags & (MSG_OOB))
+		return -EOPNOTSUPP;
+
+	if (sk->sk_state == MISDN_CLOSED)
+		return 0;
+
+	skb = skb_recv_datagram(sk, flags, &err);
+	if (!skb)
+		return err;
+
+	if (msg->msg_name) {
+		DECLARE_SOCKADDR(struct sockaddr_mISDN *, maddr, msg->msg_name);
+
+		maddr->family = AF_ISDN;
+		maddr->dev = _pms(sk)->dev->id;
+		if ((sk->sk_protocol == ISDN_P_LAPD_TE) ||
+		    (sk->sk_protocol == ISDN_P_LAPD_NT)) {
+			maddr->channel = (mISDN_HEAD_ID(skb) >> 16) & 0xff;
+			maddr->tei =  (mISDN_HEAD_ID(skb) >> 8) & 0xff;
+			maddr->sapi = mISDN_HEAD_ID(skb) & 0xff;
+		} else {
+			maddr->channel = _pms(sk)->ch.nr;
+			maddr->sapi = _pms(sk)->ch.addr & 0xFF;
+			maddr->tei =  (_pms(sk)->ch.addr >> 8) & 0xFF;
+		}
+		msg->msg_namelen = sizeof(*maddr);
+	}
+
+	copied = skb->len + MISDN_HEADER_LEN;
+	if (len < copied) {
+		if (flags & MSG_PEEK)
+			refcount_dec(&skb->users);
+		else
+			skb_queue_head(&sk->sk_receive_queue, skb);
+		return -ENOSPC;
+	}
+	memcpy(skb_push(skb, MISDN_HEADER_LEN), mISDN_HEAD_P(skb),
+	       MISDN_HEADER_LEN);
+
+	err = skb_copy_datagram_msg(skb, 0, msg, copied);
+
+	mISDN_sock_cmsg(sk, msg, skb);
+
+	skb_free_datagram(sk, skb);
+
+	return err ? : copied;
+}
+
+static int
+mISDN_sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+	struct sock		*sk = sock->sk;
+	struct sk_buff		*skb;
+	int			err = -ENOMEM;
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s: len %d flags %x ch %d proto %x\n",
+		       __func__, (int)len, msg->msg_flags, _pms(sk)->ch.nr,
+		       sk->sk_protocol);
+
+	if (msg->msg_flags & MSG_OOB)
+		return -EOPNOTSUPP;
+
+	if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_NOSIGNAL | MSG_ERRQUEUE))
+		return -EINVAL;
+
+	if (len < MISDN_HEADER_LEN)
+		return -EINVAL;
+
+	if (sk->sk_state != MISDN_BOUND)
+		return -EBADFD;
+
+	lock_sock(sk);
+
+	skb = _l2_alloc_skb(len, GFP_KERNEL);
+	if (!skb)
+		goto done;
+
+	if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
+		err = -EFAULT;
+		goto done;
+	}
+
+	memcpy(mISDN_HEAD_P(skb), skb->data, MISDN_HEADER_LEN);
+	skb_pull(skb, MISDN_HEADER_LEN);
+
+	if (msg->msg_namelen >= sizeof(struct sockaddr_mISDN)) {
+		/* if we have a address, we use it */
+		DECLARE_SOCKADDR(struct sockaddr_mISDN *, maddr, msg->msg_name);
+		mISDN_HEAD_ID(skb) = maddr->channel;
+	} else { /* use default for L2 messages */
+		if ((sk->sk_protocol == ISDN_P_LAPD_TE) ||
+		    (sk->sk_protocol == ISDN_P_LAPD_NT))
+			mISDN_HEAD_ID(skb) = _pms(sk)->ch.nr;
+	}
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s: ID:%x\n",
+		       __func__, mISDN_HEAD_ID(skb));
+
+	err = -ENODEV;
+	if (!_pms(sk)->ch.peer)
+		goto done;
+	err = _pms(sk)->ch.recv(_pms(sk)->ch.peer, skb);
+	if (err)
+		goto done;
+	else {
+		skb = NULL;
+		err = len;
+	}
+
+done:
+	kfree_skb(skb);
+	release_sock(sk);
+	return err;
+}
+
+static int
+data_sock_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
+	if (!sk)
+		return 0;
+	switch (sk->sk_protocol) {
+	case ISDN_P_TE_S0:
+	case ISDN_P_NT_S0:
+	case ISDN_P_TE_E1:
+	case ISDN_P_NT_E1:
+		if (sk->sk_state == MISDN_BOUND)
+			delete_channel(&_pms(sk)->ch);
+		else
+			mISDN_sock_unlink(&data_sockets, sk);
+		break;
+	case ISDN_P_LAPD_TE:
+	case ISDN_P_LAPD_NT:
+	case ISDN_P_B_RAW:
+	case ISDN_P_B_HDLC:
+	case ISDN_P_B_X75SLP:
+	case ISDN_P_B_L2DTMF:
+	case ISDN_P_B_L2DSP:
+	case ISDN_P_B_L2DSPHDLC:
+		delete_channel(&_pms(sk)->ch);
+		mISDN_sock_unlink(&data_sockets, sk);
+		break;
+	}
+
+	lock_sock(sk);
+
+	sock_orphan(sk);
+	skb_queue_purge(&sk->sk_receive_queue);
+
+	release_sock(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static int
+data_sock_ioctl_bound(struct sock *sk, unsigned int cmd, void __user *p)
+{
+	struct mISDN_ctrl_req	cq;
+	int			err = -EINVAL, val[2];
+	struct mISDNchannel	*bchan, *next;
+
+	lock_sock(sk);
+	if (!_pms(sk)->dev) {
+		err = -ENODEV;
+		goto done;
+	}
+	switch (cmd) {
+	case IMCTRLREQ:
+		if (copy_from_user(&cq, p, sizeof(cq))) {
+			err = -EFAULT;
+			break;
+		}
+		if ((sk->sk_protocol & ~ISDN_P_B_MASK) == ISDN_P_B_START) {
+			list_for_each_entry_safe(bchan, next,
+						 &_pms(sk)->dev->bchannels, list) {
+				if (bchan->nr == cq.channel) {
+					err = bchan->ctrl(bchan,
+							  CONTROL_CHANNEL, &cq);
+					break;
+				}
+			}
+		} else
+			err = _pms(sk)->dev->D.ctrl(&_pms(sk)->dev->D,
+						    CONTROL_CHANNEL, &cq);
+		if (err)
+			break;
+		if (copy_to_user(p, &cq, sizeof(cq)))
+			err = -EFAULT;
+		break;
+	case IMCLEAR_L2:
+		if (sk->sk_protocol != ISDN_P_LAPD_NT) {
+			err = -EINVAL;
+			break;
+		}
+		val[0] = cmd;
+		if (get_user(val[1], (int __user *)p)) {
+			err = -EFAULT;
+			break;
+		}
+		err = _pms(sk)->dev->teimgr->ctrl(_pms(sk)->dev->teimgr,
+						  CONTROL_CHANNEL, val);
+		break;
+	case IMHOLD_L1:
+		if (sk->sk_protocol != ISDN_P_LAPD_NT
+		    && sk->sk_protocol != ISDN_P_LAPD_TE) {
+			err = -EINVAL;
+			break;
+		}
+		val[0] = cmd;
+		if (get_user(val[1], (int __user *)p)) {
+			err = -EFAULT;
+			break;
+		}
+		err = _pms(sk)->dev->teimgr->ctrl(_pms(sk)->dev->teimgr,
+						  CONTROL_CHANNEL, val);
+		break;
+	default:
+		err = -EINVAL;
+		break;
+	}
+done:
+	release_sock(sk);
+	return err;
+}
+
+static int
+data_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	int			err = 0, id;
+	struct sock		*sk = sock->sk;
+	struct mISDNdevice	*dev;
+	struct mISDNversion	ver;
+
+	switch (cmd) {
+	case IMGETVERSION:
+		ver.major = MISDN_MAJOR_VERSION;
+		ver.minor = MISDN_MINOR_VERSION;
+		ver.release = MISDN_RELEASE;
+		if (copy_to_user((void __user *)arg, &ver, sizeof(ver)))
+			err = -EFAULT;
+		break;
+	case IMGETCOUNT:
+		id = get_mdevice_count();
+		if (put_user(id, (int __user *)arg))
+			err = -EFAULT;
+		break;
+	case IMGETDEVINFO:
+		if (get_user(id, (int __user *)arg)) {
+			err = -EFAULT;
+			break;
+		}
+		dev = get_mdevice(id);
+		if (dev) {
+			struct mISDN_devinfo di;
+
+			memset(&di, 0, sizeof(di));
+			di.id = dev->id;
+			di.Dprotocols = dev->Dprotocols;
+			di.Bprotocols = dev->Bprotocols | get_all_Bprotocols();
+			di.protocol = dev->D.protocol;
+			memcpy(di.channelmap, dev->channelmap,
+			       sizeof(di.channelmap));
+			di.nrbchan = dev->nrbchan;
+			strscpy(di.name, dev_name(&dev->dev), sizeof(di.name));
+			if (copy_to_user((void __user *)arg, &di, sizeof(di)))
+				err = -EFAULT;
+		} else
+			err = -ENODEV;
+		break;
+	default:
+		if (sk->sk_state == MISDN_BOUND)
+			err = data_sock_ioctl_bound(sk, cmd,
+						    (void __user *)arg);
+		else
+			err = -ENOTCONN;
+	}
+	return err;
+}
+
+static int data_sock_setsockopt(struct socket *sock, int level, int optname,
+				sockptr_t optval, unsigned int len)
+{
+	struct sock *sk = sock->sk;
+	int err = 0, opt = 0;
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s(%p, %d, %x, optval, %d)\n", __func__, sock,
+		       level, optname, len);
+
+	lock_sock(sk);
+
+	switch (optname) {
+	case MISDN_TIME_STAMP:
+		if (copy_from_sockptr(&opt, optval, sizeof(int))) {
+			err = -EFAULT;
+			break;
+		}
+
+		if (opt)
+			_pms(sk)->cmask |= MISDN_TIME_STAMP;
+		else
+			_pms(sk)->cmask &= ~MISDN_TIME_STAMP;
+		break;
+	default:
+		err = -ENOPROTOOPT;
+		break;
+	}
+	release_sock(sk);
+	return err;
+}
+
+static int data_sock_getsockopt(struct socket *sock, int level, int optname,
+				char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+	int len, opt;
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+
+	if (len != sizeof(char))
+		return -EINVAL;
+
+	switch (optname) {
+	case MISDN_TIME_STAMP:
+		if (_pms(sk)->cmask & MISDN_TIME_STAMP)
+			opt = 1;
+		else
+			opt = 0;
+
+		if (put_user(opt, optval))
+			return -EFAULT;
+		break;
+	default:
+		return -ENOPROTOOPT;
+	}
+
+	return 0;
+}
+
+static int
+data_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
+{
+	struct sockaddr_mISDN *maddr = (struct sockaddr_mISDN *) addr;
+	struct sock *sk = sock->sk;
+	struct sock *csk;
+	int err = 0;
+
+	if (*debug & DEBUG_SOCKET)
+		printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
+	if (addr_len != sizeof(struct sockaddr_mISDN))
+		return -EINVAL;
+	if (!maddr || maddr->family != AF_ISDN)
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	if (_pms(sk)->dev) {
+		err = -EALREADY;
+		goto done;
+	}
+	_pms(sk)->dev = get_mdevice(maddr->dev);
+	if (!_pms(sk)->dev) {
+		err = -ENODEV;
+		goto done;
+	}
+
+	if (sk->sk_protocol < ISDN_P_B_START) {
+		read_lock_bh(&data_sockets.lock);
+		sk_for_each(csk, &data_sockets.head) {
+			if (sk == csk)
+				continue;
+			if (_pms(csk)->dev != _pms(sk)->dev)
+				continue;
+			if (csk->sk_protocol >= ISDN_P_B_START)
+				continue;
+			if (IS_ISDN_P_TE(csk->sk_protocol)
+			    == IS_ISDN_P_TE(sk->sk_protocol))
+				continue;
+			read_unlock_bh(&data_sockets.lock);
+			err = -EBUSY;
+			goto done;
+		}
+		read_unlock_bh(&data_sockets.lock);
+	}
+
+	_pms(sk)->ch.send = mISDN_send;
+	_pms(sk)->ch.ctrl = mISDN_ctrl;
+
+	switch (sk->sk_protocol) {
+	case ISDN_P_TE_S0:
+	case ISDN_P_NT_S0:
+	case ISDN_P_TE_E1:
+	case ISDN_P_NT_E1:
+		mISDN_sock_unlink(&data_sockets, sk);
+		err = connect_layer1(_pms(sk)->dev, &_pms(sk)->ch,
+				     sk->sk_protocol, maddr);
+		if (err)
+			mISDN_sock_link(&data_sockets, sk);
+		break;
+	case ISDN_P_LAPD_TE:
+	case ISDN_P_LAPD_NT:
+		err = create_l2entity(_pms(sk)->dev, &_pms(sk)->ch,
+				      sk->sk_protocol, maddr);
+		break;
+	case ISDN_P_B_RAW:
+	case ISDN_P_B_HDLC:
+	case ISDN_P_B_X75SLP:
+	case ISDN_P_B_L2DTMF:
+	case ISDN_P_B_L2DSP:
+	case ISDN_P_B_L2DSPHDLC:
+		err = connect_Bstack(_pms(sk)->dev, &_pms(sk)->ch,
+				     sk->sk_protocol, maddr);
+		break;
+	default:
+		err = -EPROTONOSUPPORT;
+	}
+	if (err)
+		goto done;
+	sk->sk_state = MISDN_BOUND;
+	_pms(sk)->ch.protocol = sk->sk_protocol;
+
+done:
+	release_sock(sk);
+	return err;
+}
+
+static int
+data_sock_getname(struct socket *sock, struct sockaddr *addr,
+		  int peer)
+{
+	struct sockaddr_mISDN	*maddr = (struct sockaddr_mISDN *) addr;
+	struct sock		*sk = sock->sk;
+
+	if (!_pms(sk)->dev)
+		return -EBADFD;
+
+	lock_sock(sk);
+
+	maddr->family = AF_ISDN;
+	maddr->dev = _pms(sk)->dev->id;
+	maddr->channel = _pms(sk)->ch.nr;
+	maddr->sapi = _pms(sk)->ch.addr & 0xff;
+	maddr->tei = (_pms(sk)->ch.addr >> 8) & 0xff;
+	release_sock(sk);
+	return sizeof(*maddr);
+}
+
+static const struct proto_ops data_sock_ops = {
+	.family		= PF_ISDN,
+	.owner		= THIS_MODULE,
+	.release	= data_sock_release,
+	.ioctl		= data_sock_ioctl,
+	.bind		= data_sock_bind,
+	.getname	= data_sock_getname,
+	.sendmsg	= mISDN_sock_sendmsg,
+	.recvmsg	= mISDN_sock_recvmsg,
+	.poll		= datagram_poll,
+	.listen		= sock_no_listen,
+	.shutdown	= sock_no_shutdown,
+	.setsockopt	= data_sock_setsockopt,
+	.getsockopt	= data_sock_getsockopt,
+	.connect	= sock_no_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.mmap		= sock_no_mmap
+};
+
+static int
+data_sock_create(struct net *net, struct socket *sock, int protocol, int kern)
+{
+	struct sock *sk;
+
+	if (sock->type != SOCK_DGRAM)
+		return -ESOCKTNOSUPPORT;
+
+	sk = sk_alloc(net, PF_ISDN, GFP_KERNEL, &mISDN_proto, kern);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_init_data(sock, sk);
+
+	sock->ops = &data_sock_ops;
+	sock->state = SS_UNCONNECTED;
+	sock_reset_flag(sk, SOCK_ZAPPED);
+
+	sk->sk_protocol = protocol;
+	sk->sk_state    = MISDN_OPEN;
+	mISDN_sock_link(&data_sockets, sk);
+
+	return 0;
+}
+
+static int
+base_sock_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+
+	printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
+	if (!sk)
+		return 0;
+
+	mISDN_sock_unlink(&base_sockets, sk);
+	sock_orphan(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static int
+base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	int			err = 0, id;
+	struct mISDNdevice	*dev;
+	struct mISDNversion	ver;
+
+	switch (cmd) {
+	case IMGETVERSION:
+		ver.major = MISDN_MAJOR_VERSION;
+		ver.minor = MISDN_MINOR_VERSION;
+		ver.release = MISDN_RELEASE;
+		if (copy_to_user((void __user *)arg, &ver, sizeof(ver)))
+			err = -EFAULT;
+		break;
+	case IMGETCOUNT:
+		id = get_mdevice_count();
+		if (put_user(id, (int __user *)arg))
+			err = -EFAULT;
+		break;
+	case IMGETDEVINFO:
+		if (get_user(id, (int __user *)arg)) {
+			err = -EFAULT;
+			break;
+		}
+		dev = get_mdevice(id);
+		if (dev) {
+			struct mISDN_devinfo di;
+
+			memset(&di, 0, sizeof(di));
+			di.id = dev->id;
+			di.Dprotocols = dev->Dprotocols;
+			di.Bprotocols = dev->Bprotocols | get_all_Bprotocols();
+			di.protocol = dev->D.protocol;
+			memcpy(di.channelmap, dev->channelmap,
+			       sizeof(di.channelmap));
+			di.nrbchan = dev->nrbchan;
+			strscpy(di.name, dev_name(&dev->dev), sizeof(di.name));
+			if (copy_to_user((void __user *)arg, &di, sizeof(di)))
+				err = -EFAULT;
+		} else
+			err = -ENODEV;
+		break;
+	case IMSETDEVNAME:
+	{
+		struct mISDN_devrename dn;
+		if (copy_from_user(&dn, (void __user *)arg,
+				   sizeof(dn))) {
+			err = -EFAULT;
+			break;
+		}
+		dn.name[sizeof(dn.name) - 1] = '\0';
+		dev = get_mdevice(dn.id);
+		if (dev)
+			err = device_rename(&dev->dev, dn.name);
+		else
+			err = -ENODEV;
+	}
+	break;
+	default:
+		err = -EINVAL;
+	}
+	return err;
+}
+
+static int
+base_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
+{
+	struct sockaddr_mISDN *maddr = (struct sockaddr_mISDN *) addr;
+	struct sock *sk = sock->sk;
+	int err = 0;
+
+	if (addr_len < sizeof(struct sockaddr_mISDN))
+		return -EINVAL;
+
+	if (!maddr || maddr->family != AF_ISDN)
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	if (_pms(sk)->dev) {
+		err = -EALREADY;
+		goto done;
+	}
+
+	_pms(sk)->dev = get_mdevice(maddr->dev);
+	if (!_pms(sk)->dev) {
+		err = -ENODEV;
+		goto done;
+	}
+	sk->sk_state = MISDN_BOUND;
+
+done:
+	release_sock(sk);
+	return err;
+}
+
+static const struct proto_ops base_sock_ops = {
+	.family		= PF_ISDN,
+	.owner		= THIS_MODULE,
+	.release	= base_sock_release,
+	.ioctl		= base_sock_ioctl,
+	.bind		= base_sock_bind,
+	.getname	= sock_no_getname,
+	.sendmsg	= sock_no_sendmsg,
+	.recvmsg	= sock_no_recvmsg,
+	.listen		= sock_no_listen,
+	.shutdown	= sock_no_shutdown,
+	.connect	= sock_no_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.mmap		= sock_no_mmap
+};
+
+
+static int
+base_sock_create(struct net *net, struct socket *sock, int protocol, int kern)
+{
+	struct sock *sk;
+
+	if (sock->type != SOCK_RAW)
+		return -ESOCKTNOSUPPORT;
+	if (!capable(CAP_NET_RAW))
+		return -EPERM;
+
+	sk = sk_alloc(net, PF_ISDN, GFP_KERNEL, &mISDN_proto, kern);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_init_data(sock, sk);
+	sock->ops = &base_sock_ops;
+	sock->state = SS_UNCONNECTED;
+	sock_reset_flag(sk, SOCK_ZAPPED);
+	sk->sk_protocol = protocol;
+	sk->sk_state    = MISDN_OPEN;
+	mISDN_sock_link(&base_sockets, sk);
+
+	return 0;
+}
+
+static int
+mISDN_sock_create(struct net *net, struct socket *sock, int proto, int kern)
+{
+	int err = -EPROTONOSUPPORT;
+
+	switch (proto) {
+	case ISDN_P_BASE:
+		err = base_sock_create(net, sock, proto, kern);
+		break;
+	case ISDN_P_TE_S0:
+	case ISDN_P_NT_S0:
+	case ISDN_P_TE_E1:
+	case ISDN_P_NT_E1:
+	case ISDN_P_LAPD_TE:
+	case ISDN_P_LAPD_NT:
+	case ISDN_P_B_RAW:
+	case ISDN_P_B_HDLC:
+	case ISDN_P_B_X75SLP:
+	case ISDN_P_B_L2DTMF:
+	case ISDN_P_B_L2DSP:
+	case ISDN_P_B_L2DSPHDLC:
+		err = data_sock_create(net, sock, proto, kern);
+		break;
+	default:
+		return err;
+	}
+
+	return err;
+}
+
+static const struct net_proto_family mISDN_sock_family_ops = {
+	.owner  = THIS_MODULE,
+	.family = PF_ISDN,
+	.create = mISDN_sock_create,
+};
+
+int
+misdn_sock_init(u_int *deb)
+{
+	int err;
+
+	debug = deb;
+	err = sock_register(&mISDN_sock_family_ops);
+	if (err)
+		printk(KERN_ERR "%s: error(%d)\n", __func__, err);
+	return err;
+}
+
+void
+misdn_sock_cleanup(void)
+{
+	sock_unregister(PF_ISDN);
+}
diff --git a/drivers/isdn/mISDN/stack.c b/drivers/isdn/mISDN/stack.c
new file mode 100644
index 000000000..c2f76f398
--- /dev/null
+++ b/drivers/isdn/mISDN/stack.c
@@ -0,0 +1,654 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/slab.h>
+#include <linux/mISDNif.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/sched/cputime.h>
+#include <linux/signal.h>
+
+#include "core.h"
+
+static u_int	*debug;
+
+static inline void
+_queue_message(struct mISDNstack *st, struct sk_buff *skb)
+{
+	struct mISDNhead	*hh = mISDN_HEAD_P(skb);
+
+	if (*debug & DEBUG_QUEUE_FUNC)
+		printk(KERN_DEBUG "%s prim(%x) id(%x) %p\n",
+		       __func__, hh->prim, hh->id, skb);
+	skb_queue_tail(&st->msgq, skb);
+	if (likely(!test_bit(mISDN_STACK_STOPPED, &st->status))) {
+		test_and_set_bit(mISDN_STACK_WORK, &st->status);
+		wake_up_interruptible(&st->workq);
+	}
+}
+
+static int
+mISDN_queue_message(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	_queue_message(ch->st, skb);
+	return 0;
+}
+
+static struct mISDNchannel *
+get_channel4id(struct mISDNstack *st, u_int id)
+{
+	struct mISDNchannel	*ch;
+
+	mutex_lock(&st->lmutex);
+	list_for_each_entry(ch, &st->layer2, list) {
+		if (id == ch->nr)
+			goto unlock;
+	}
+	ch = NULL;
+unlock:
+	mutex_unlock(&st->lmutex);
+	return ch;
+}
+
+static void
+send_socklist(struct mISDN_sock_list *sl, struct sk_buff *skb)
+{
+	struct sock		*sk;
+	struct sk_buff		*cskb = NULL;
+
+	read_lock(&sl->lock);
+	sk_for_each(sk, &sl->head) {
+		if (sk->sk_state != MISDN_BOUND)
+			continue;
+		if (!cskb)
+			cskb = skb_copy(skb, GFP_ATOMIC);
+		if (!cskb) {
+			printk(KERN_WARNING "%s no skb\n", __func__);
+			break;
+		}
+		if (!sock_queue_rcv_skb(sk, cskb))
+			cskb = NULL;
+	}
+	read_unlock(&sl->lock);
+	dev_kfree_skb(cskb);
+}
+
+static void
+send_layer2(struct mISDNstack *st, struct sk_buff *skb)
+{
+	struct sk_buff		*cskb;
+	struct mISDNhead	*hh = mISDN_HEAD_P(skb);
+	struct mISDNchannel	*ch;
+	int			ret;
+
+	if (!st)
+		return;
+	mutex_lock(&st->lmutex);
+	if ((hh->id & MISDN_ID_ADDR_MASK) == MISDN_ID_ANY) { /* L2 for all */
+		list_for_each_entry(ch, &st->layer2, list) {
+			if (list_is_last(&ch->list, &st->layer2)) {
+				cskb = skb;
+				skb = NULL;
+			} else {
+				cskb = skb_copy(skb, GFP_KERNEL);
+			}
+			if (cskb) {
+				ret = ch->send(ch, cskb);
+				if (ret) {
+					if (*debug & DEBUG_SEND_ERR)
+						printk(KERN_DEBUG
+						       "%s ch%d prim(%x) addr(%x)"
+						       " err %d\n",
+						       __func__, ch->nr,
+						       hh->prim, ch->addr, ret);
+					dev_kfree_skb(cskb);
+				}
+			} else {
+				printk(KERN_WARNING "%s ch%d addr %x no mem\n",
+				       __func__, ch->nr, ch->addr);
+				goto out;
+			}
+		}
+	} else {
+		list_for_each_entry(ch, &st->layer2, list) {
+			if ((hh->id & MISDN_ID_ADDR_MASK) == ch->addr) {
+				ret = ch->send(ch, skb);
+				if (!ret)
+					skb = NULL;
+				goto out;
+			}
+		}
+		ret = st->dev->teimgr->ctrl(st->dev->teimgr, CHECK_DATA, skb);
+		if (!ret)
+			skb = NULL;
+		else if (*debug & DEBUG_SEND_ERR)
+			printk(KERN_DEBUG
+			       "%s mgr prim(%x) err %d\n",
+			       __func__, hh->prim, ret);
+	}
+out:
+	mutex_unlock(&st->lmutex);
+	dev_kfree_skb(skb);
+}
+
+static inline int
+send_msg_to_layer(struct mISDNstack *st, struct sk_buff *skb)
+{
+	struct mISDNhead	*hh = mISDN_HEAD_P(skb);
+	struct mISDNchannel	*ch;
+	int	lm;
+
+	lm = hh->prim & MISDN_LAYERMASK;
+	if (*debug & DEBUG_QUEUE_FUNC)
+		printk(KERN_DEBUG "%s prim(%x) id(%x) %p\n",
+		       __func__, hh->prim, hh->id, skb);
+	if (lm == 0x1) {
+		if (!hlist_empty(&st->l1sock.head)) {
+			__net_timestamp(skb);
+			send_socklist(&st->l1sock, skb);
+		}
+		return st->layer1->send(st->layer1, skb);
+	} else if (lm == 0x2) {
+		if (!hlist_empty(&st->l1sock.head))
+			send_socklist(&st->l1sock, skb);
+		send_layer2(st, skb);
+		return 0;
+	} else if (lm == 0x4) {
+		ch = get_channel4id(st, hh->id);
+		if (ch)
+			return ch->send(ch, skb);
+		else
+			printk(KERN_WARNING
+			       "%s: dev(%s) prim(%x) id(%x) no channel\n",
+			       __func__, dev_name(&st->dev->dev), hh->prim,
+			       hh->id);
+	} else if (lm == 0x8) {
+		WARN_ON(lm == 0x8);
+		ch = get_channel4id(st, hh->id);
+		if (ch)
+			return ch->send(ch, skb);
+		else
+			printk(KERN_WARNING
+			       "%s: dev(%s) prim(%x) id(%x) no channel\n",
+			       __func__, dev_name(&st->dev->dev), hh->prim,
+			       hh->id);
+	} else {
+		/* broadcast not handled yet */
+		printk(KERN_WARNING "%s: dev(%s) prim %x not delivered\n",
+		       __func__, dev_name(&st->dev->dev), hh->prim);
+	}
+	return -ESRCH;
+}
+
+static void
+do_clear_stack(struct mISDNstack *st)
+{
+}
+
+static int
+mISDNStackd(void *data)
+{
+	struct mISDNstack *st = data;
+#ifdef MISDN_MSG_STATS
+	u64 utime, stime;
+#endif
+	int err = 0;
+
+	sigfillset(&current->blocked);
+	if (*debug & DEBUG_MSG_THREAD)
+		printk(KERN_DEBUG "mISDNStackd %s started\n",
+		       dev_name(&st->dev->dev));
+
+	if (st->notify != NULL) {
+		complete(st->notify);
+		st->notify = NULL;
+	}
+
+	for (;;) {
+		struct sk_buff	*skb;
+
+		if (unlikely(test_bit(mISDN_STACK_STOPPED, &st->status))) {
+			test_and_clear_bit(mISDN_STACK_WORK, &st->status);
+			test_and_clear_bit(mISDN_STACK_RUNNING, &st->status);
+		} else
+			test_and_set_bit(mISDN_STACK_RUNNING, &st->status);
+		while (test_bit(mISDN_STACK_WORK, &st->status)) {
+			skb = skb_dequeue(&st->msgq);
+			if (!skb) {
+				test_and_clear_bit(mISDN_STACK_WORK,
+						   &st->status);
+				/* test if a race happens */
+				skb = skb_dequeue(&st->msgq);
+				if (!skb)
+					continue;
+				test_and_set_bit(mISDN_STACK_WORK,
+						 &st->status);
+			}
+#ifdef MISDN_MSG_STATS
+			st->msg_cnt++;
+#endif
+			err = send_msg_to_layer(st, skb);
+			if (unlikely(err)) {
+				if (*debug & DEBUG_SEND_ERR)
+					printk(KERN_DEBUG
+					       "%s: %s prim(%x) id(%x) "
+					       "send call(%d)\n",
+					       __func__, dev_name(&st->dev->dev),
+					       mISDN_HEAD_PRIM(skb),
+					       mISDN_HEAD_ID(skb), err);
+				dev_kfree_skb(skb);
+				continue;
+			}
+			if (unlikely(test_bit(mISDN_STACK_STOPPED,
+					      &st->status))) {
+				test_and_clear_bit(mISDN_STACK_WORK,
+						   &st->status);
+				test_and_clear_bit(mISDN_STACK_RUNNING,
+						   &st->status);
+				break;
+			}
+		}
+		if (test_bit(mISDN_STACK_CLEARING, &st->status)) {
+			test_and_set_bit(mISDN_STACK_STOPPED, &st->status);
+			test_and_clear_bit(mISDN_STACK_RUNNING, &st->status);
+			do_clear_stack(st);
+			test_and_clear_bit(mISDN_STACK_CLEARING, &st->status);
+			test_and_set_bit(mISDN_STACK_RESTART, &st->status);
+		}
+		if (test_and_clear_bit(mISDN_STACK_RESTART, &st->status)) {
+			test_and_clear_bit(mISDN_STACK_STOPPED, &st->status);
+			test_and_set_bit(mISDN_STACK_RUNNING, &st->status);
+			if (!skb_queue_empty(&st->msgq))
+				test_and_set_bit(mISDN_STACK_WORK,
+						 &st->status);
+		}
+		if (test_bit(mISDN_STACK_ABORT, &st->status))
+			break;
+		if (st->notify != NULL) {
+			complete(st->notify);
+			st->notify = NULL;
+		}
+#ifdef MISDN_MSG_STATS
+		st->sleep_cnt++;
+#endif
+		test_and_clear_bit(mISDN_STACK_ACTIVE, &st->status);
+		wait_event_interruptible(st->workq, (st->status &
+						     mISDN_STACK_ACTION_MASK));
+		if (*debug & DEBUG_MSG_THREAD)
+			printk(KERN_DEBUG "%s: %s wake status %08lx\n",
+			       __func__, dev_name(&st->dev->dev), st->status);
+		test_and_set_bit(mISDN_STACK_ACTIVE, &st->status);
+
+		test_and_clear_bit(mISDN_STACK_WAKEUP, &st->status);
+
+		if (test_bit(mISDN_STACK_STOPPED, &st->status)) {
+			test_and_clear_bit(mISDN_STACK_RUNNING, &st->status);
+#ifdef MISDN_MSG_STATS
+			st->stopped_cnt++;
+#endif
+		}
+	}
+#ifdef MISDN_MSG_STATS
+	printk(KERN_DEBUG "mISDNStackd daemon for %s proceed %d "
+	       "msg %d sleep %d stopped\n",
+	       dev_name(&st->dev->dev), st->msg_cnt, st->sleep_cnt,
+	       st->stopped_cnt);
+	task_cputime(st->thread, &utime, &stime);
+	printk(KERN_DEBUG
+	       "mISDNStackd daemon for %s utime(%llu) stime(%llu)\n",
+	       dev_name(&st->dev->dev), utime, stime);
+	printk(KERN_DEBUG
+	       "mISDNStackd daemon for %s nvcsw(%ld) nivcsw(%ld)\n",
+	       dev_name(&st->dev->dev), st->thread->nvcsw, st->thread->nivcsw);
+	printk(KERN_DEBUG "mISDNStackd daemon for %s killed now\n",
+	       dev_name(&st->dev->dev));
+#endif
+	test_and_set_bit(mISDN_STACK_KILLED, &st->status);
+	test_and_clear_bit(mISDN_STACK_RUNNING, &st->status);
+	test_and_clear_bit(mISDN_STACK_ACTIVE, &st->status);
+	test_and_clear_bit(mISDN_STACK_ABORT, &st->status);
+	skb_queue_purge(&st->msgq);
+	st->thread = NULL;
+	if (st->notify != NULL) {
+		complete(st->notify);
+		st->notify = NULL;
+	}
+	return 0;
+}
+
+static int
+l1_receive(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	if (!ch->st)
+		return -ENODEV;
+	__net_timestamp(skb);
+	_queue_message(ch->st, skb);
+	return 0;
+}
+
+void
+set_channel_address(struct mISDNchannel *ch, u_int sapi, u_int tei)
+{
+	ch->addr = sapi | (tei << 8);
+}
+
+void
+__add_layer2(struct mISDNchannel *ch, struct mISDNstack *st)
+{
+	list_add_tail(&ch->list, &st->layer2);
+}
+
+void
+add_layer2(struct mISDNchannel *ch, struct mISDNstack *st)
+{
+	mutex_lock(&st->lmutex);
+	__add_layer2(ch, st);
+	mutex_unlock(&st->lmutex);
+}
+
+static int
+st_own_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	if (!ch->st || !ch->st->layer1)
+		return -EINVAL;
+	return ch->st->layer1->ctrl(ch->st->layer1, cmd, arg);
+}
+
+int
+create_stack(struct mISDNdevice *dev)
+{
+	struct mISDNstack	*newst;
+	int			err;
+	DECLARE_COMPLETION_ONSTACK(done);
+
+	newst = kzalloc(sizeof(struct mISDNstack), GFP_KERNEL);
+	if (!newst) {
+		printk(KERN_ERR "kmalloc mISDN_stack failed\n");
+		return -ENOMEM;
+	}
+	newst->dev = dev;
+	INIT_LIST_HEAD(&newst->layer2);
+	INIT_HLIST_HEAD(&newst->l1sock.head);
+	rwlock_init(&newst->l1sock.lock);
+	init_waitqueue_head(&newst->workq);
+	skb_queue_head_init(&newst->msgq);
+	mutex_init(&newst->lmutex);
+	dev->D.st = newst;
+	err = create_teimanager(dev);
+	if (err) {
+		printk(KERN_ERR "kmalloc teimanager failed\n");
+		kfree(newst);
+		return err;
+	}
+	dev->teimgr->peer = &newst->own;
+	dev->teimgr->recv = mISDN_queue_message;
+	dev->teimgr->st = newst;
+	newst->layer1 = &dev->D;
+	dev->D.recv = l1_receive;
+	dev->D.peer = &newst->own;
+	newst->own.st = newst;
+	newst->own.ctrl = st_own_ctrl;
+	newst->own.send = mISDN_queue_message;
+	newst->own.recv = mISDN_queue_message;
+	if (*debug & DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: st(%s)\n", __func__,
+		       dev_name(&newst->dev->dev));
+	newst->notify = &done;
+	newst->thread = kthread_run(mISDNStackd, (void *)newst, "mISDN_%s",
+				    dev_name(&newst->dev->dev));
+	if (IS_ERR(newst->thread)) {
+		err = PTR_ERR(newst->thread);
+		printk(KERN_ERR
+		       "mISDN:cannot create kernel thread for %s (%d)\n",
+		       dev_name(&newst->dev->dev), err);
+		delete_teimanager(dev->teimgr);
+		kfree(newst);
+	} else
+		wait_for_completion(&done);
+	return err;
+}
+
+int
+connect_layer1(struct mISDNdevice *dev, struct mISDNchannel *ch,
+	       u_int protocol, struct sockaddr_mISDN *adr)
+{
+	struct mISDN_sock	*msk = container_of(ch, struct mISDN_sock, ch);
+	struct channel_req	rq;
+	int			err;
+
+
+	if (*debug &  DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: %s proto(%x) adr(%d %d %d %d)\n",
+		       __func__, dev_name(&dev->dev), protocol, adr->dev,
+		       adr->channel, adr->sapi, adr->tei);
+	switch (protocol) {
+	case ISDN_P_NT_S0:
+	case ISDN_P_NT_E1:
+	case ISDN_P_TE_S0:
+	case ISDN_P_TE_E1:
+		ch->recv = mISDN_queue_message;
+		ch->peer = &dev->D.st->own;
+		ch->st = dev->D.st;
+		rq.protocol = protocol;
+		rq.adr.channel = adr->channel;
+		err = dev->D.ctrl(&dev->D, OPEN_CHANNEL, &rq);
+		printk(KERN_DEBUG "%s: ret %d (dev %d)\n", __func__, err,
+		       dev->id);
+		if (err)
+			return err;
+		write_lock_bh(&dev->D.st->l1sock.lock);
+		sk_add_node(&msk->sk, &dev->D.st->l1sock.head);
+		write_unlock_bh(&dev->D.st->l1sock.lock);
+		break;
+	default:
+		return -ENOPROTOOPT;
+	}
+	return 0;
+}
+
+int
+connect_Bstack(struct mISDNdevice *dev, struct mISDNchannel *ch,
+	       u_int protocol, struct sockaddr_mISDN *adr)
+{
+	struct channel_req	rq, rq2;
+	int			pmask, err;
+	struct Bprotocol	*bp;
+
+	if (*debug &  DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: %s proto(%x) adr(%d %d %d %d)\n",
+		       __func__, dev_name(&dev->dev), protocol,
+		       adr->dev, adr->channel, adr->sapi,
+		       adr->tei);
+	ch->st = dev->D.st;
+	pmask = 1 << (protocol & ISDN_P_B_MASK);
+	if (pmask & dev->Bprotocols) {
+		rq.protocol = protocol;
+		rq.adr = *adr;
+		err = dev->D.ctrl(&dev->D, OPEN_CHANNEL, &rq);
+		if (err)
+			return err;
+		ch->recv = rq.ch->send;
+		ch->peer = rq.ch;
+		rq.ch->recv = ch->send;
+		rq.ch->peer = ch;
+		rq.ch->st = dev->D.st;
+	} else {
+		bp = get_Bprotocol4mask(pmask);
+		if (!bp)
+			return -ENOPROTOOPT;
+		rq2.protocol = protocol;
+		rq2.adr = *adr;
+		rq2.ch = ch;
+		err = bp->create(&rq2);
+		if (err)
+			return err;
+		ch->recv = rq2.ch->send;
+		ch->peer = rq2.ch;
+		rq2.ch->st = dev->D.st;
+		rq.protocol = rq2.protocol;
+		rq.adr = *adr;
+		err = dev->D.ctrl(&dev->D, OPEN_CHANNEL, &rq);
+		if (err) {
+			rq2.ch->ctrl(rq2.ch, CLOSE_CHANNEL, NULL);
+			return err;
+		}
+		rq2.ch->recv = rq.ch->send;
+		rq2.ch->peer = rq.ch;
+		rq.ch->recv = rq2.ch->send;
+		rq.ch->peer = rq2.ch;
+		rq.ch->st = dev->D.st;
+	}
+	ch->protocol = protocol;
+	ch->nr = rq.ch->nr;
+	return 0;
+}
+
+int
+create_l2entity(struct mISDNdevice *dev, struct mISDNchannel *ch,
+		u_int protocol, struct sockaddr_mISDN *adr)
+{
+	struct channel_req	rq;
+	int			err;
+
+	if (*debug &  DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: %s proto(%x) adr(%d %d %d %d)\n",
+		       __func__, dev_name(&dev->dev), protocol,
+		       adr->dev, adr->channel, adr->sapi,
+		       adr->tei);
+	rq.protocol = ISDN_P_TE_S0;
+	if (dev->Dprotocols & (1 << ISDN_P_TE_E1))
+		rq.protocol = ISDN_P_TE_E1;
+	switch (protocol) {
+	case ISDN_P_LAPD_NT:
+		rq.protocol = ISDN_P_NT_S0;
+		if (dev->Dprotocols & (1 << ISDN_P_NT_E1))
+			rq.protocol = ISDN_P_NT_E1;
+		fallthrough;
+	case ISDN_P_LAPD_TE:
+		ch->recv = mISDN_queue_message;
+		ch->peer = &dev->D.st->own;
+		ch->st = dev->D.st;
+		rq.adr.channel = 0;
+		err = dev->D.ctrl(&dev->D, OPEN_CHANNEL, &rq);
+		printk(KERN_DEBUG "%s: ret 1 %d\n", __func__, err);
+		if (err)
+			break;
+		rq.protocol = protocol;
+		rq.adr = *adr;
+		rq.ch = ch;
+		err = dev->teimgr->ctrl(dev->teimgr, OPEN_CHANNEL, &rq);
+		printk(KERN_DEBUG "%s: ret 2 %d\n", __func__, err);
+		if (!err) {
+			if ((protocol == ISDN_P_LAPD_NT) && !rq.ch)
+				break;
+			add_layer2(rq.ch, dev->D.st);
+			rq.ch->recv = mISDN_queue_message;
+			rq.ch->peer = &dev->D.st->own;
+			rq.ch->ctrl(rq.ch, OPEN_CHANNEL, NULL); /* can't fail */
+		}
+		break;
+	default:
+		err = -EPROTONOSUPPORT;
+	}
+	return err;
+}
+
+void
+delete_channel(struct mISDNchannel *ch)
+{
+	struct mISDN_sock	*msk = container_of(ch, struct mISDN_sock, ch);
+	struct mISDNchannel	*pch;
+
+	if (!ch->st) {
+		printk(KERN_WARNING "%s: no stack\n", __func__);
+		return;
+	}
+	if (*debug & DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: st(%s) protocol(%x)\n", __func__,
+		       dev_name(&ch->st->dev->dev), ch->protocol);
+	if (ch->protocol >= ISDN_P_B_START) {
+		if (ch->peer) {
+			ch->peer->ctrl(ch->peer, CLOSE_CHANNEL, NULL);
+			ch->peer = NULL;
+		}
+		return;
+	}
+	switch (ch->protocol) {
+	case ISDN_P_NT_S0:
+	case ISDN_P_TE_S0:
+	case ISDN_P_NT_E1:
+	case ISDN_P_TE_E1:
+		write_lock_bh(&ch->st->l1sock.lock);
+		sk_del_node_init(&msk->sk);
+		write_unlock_bh(&ch->st->l1sock.lock);
+		ch->st->dev->D.ctrl(&ch->st->dev->D, CLOSE_CHANNEL, NULL);
+		break;
+	case ISDN_P_LAPD_TE:
+		pch = get_channel4id(ch->st, ch->nr);
+		if (pch) {
+			mutex_lock(&ch->st->lmutex);
+			list_del(&pch->list);
+			mutex_unlock(&ch->st->lmutex);
+			pch->ctrl(pch, CLOSE_CHANNEL, NULL);
+			pch = ch->st->dev->teimgr;
+			pch->ctrl(pch, CLOSE_CHANNEL, NULL);
+		} else
+			printk(KERN_WARNING "%s: no l2 channel\n",
+			       __func__);
+		break;
+	case ISDN_P_LAPD_NT:
+		pch = ch->st->dev->teimgr;
+		if (pch) {
+			pch->ctrl(pch, CLOSE_CHANNEL, NULL);
+		} else
+			printk(KERN_WARNING "%s: no l2 channel\n",
+			       __func__);
+		break;
+	default:
+		break;
+	}
+	return;
+}
+
+void
+delete_stack(struct mISDNdevice *dev)
+{
+	struct mISDNstack	*st = dev->D.st;
+	DECLARE_COMPLETION_ONSTACK(done);
+
+	if (*debug & DEBUG_CORE_FUNC)
+		printk(KERN_DEBUG "%s: st(%s)\n", __func__,
+		       dev_name(&st->dev->dev));
+	if (dev->teimgr)
+		delete_teimanager(dev->teimgr);
+	if (st->thread) {
+		if (st->notify) {
+			printk(KERN_WARNING "%s: notifier in use\n",
+			       __func__);
+			complete(st->notify);
+		}
+		st->notify = &done;
+		test_and_set_bit(mISDN_STACK_ABORT, &st->status);
+		test_and_set_bit(mISDN_STACK_WAKEUP, &st->status);
+		wake_up_interruptible(&st->workq);
+		wait_for_completion(&done);
+	}
+	if (!list_empty(&st->layer2))
+		printk(KERN_WARNING "%s: layer2 list not empty\n",
+		       __func__);
+	if (!hlist_empty(&st->l1sock.head))
+		printk(KERN_WARNING "%s: layer1 list not empty\n",
+		       __func__);
+	kfree(st);
+}
+
+void
+mISDN_initstack(u_int *dp)
+{
+	debug = dp;
+}
diff --git a/drivers/isdn/mISDN/tei.c b/drivers/isdn/mISDN/tei.c
new file mode 100644
index 000000000..59d28cb19
--- /dev/null
+++ b/drivers/isdn/mISDN/tei.c
@@ -0,0 +1,1416 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+#include "layer2.h"
+#include <linux/random.h>
+#include <linux/slab.h>
+#include "core.h"
+
+#define ID_REQUEST	1
+#define ID_ASSIGNED	2
+#define ID_DENIED	3
+#define ID_CHK_REQ	4
+#define ID_CHK_RES	5
+#define ID_REMOVE	6
+#define ID_VERIFY	7
+
+#define TEI_ENTITY_ID	0xf
+
+#define MGR_PH_ACTIVE	16
+#define MGR_PH_NOTREADY	17
+
+#define DATIMER_VAL	10000
+
+static	u_int	*debug;
+
+static struct Fsm deactfsm = {NULL, 0, 0, NULL, NULL};
+static struct Fsm teifsmu = {NULL, 0, 0, NULL, NULL};
+static struct Fsm teifsmn = {NULL, 0, 0, NULL, NULL};
+
+enum {
+	ST_L1_DEACT,
+	ST_L1_DEACT_PENDING,
+	ST_L1_ACTIV,
+};
+#define DEACT_STATE_COUNT (ST_L1_ACTIV + 1)
+
+static char *strDeactState[] =
+{
+	"ST_L1_DEACT",
+	"ST_L1_DEACT_PENDING",
+	"ST_L1_ACTIV",
+};
+
+enum {
+	EV_ACTIVATE,
+	EV_ACTIVATE_IND,
+	EV_DEACTIVATE,
+	EV_DEACTIVATE_IND,
+	EV_UI,
+	EV_DATIMER,
+};
+
+#define DEACT_EVENT_COUNT (EV_DATIMER + 1)
+
+static char *strDeactEvent[] =
+{
+	"EV_ACTIVATE",
+	"EV_ACTIVATE_IND",
+	"EV_DEACTIVATE",
+	"EV_DEACTIVATE_IND",
+	"EV_UI",
+	"EV_DATIMER",
+};
+
+static void
+da_debug(struct FsmInst *fi, char *fmt, ...)
+{
+	struct manager	*mgr = fi->userdata;
+	struct va_format vaf;
+	va_list va;
+
+	if (!(*debug & DEBUG_L2_TEIFSM))
+		return;
+
+	va_start(va, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "mgr(%d): %pV\n", mgr->ch.st->dev->id, &vaf);
+
+	va_end(va);
+}
+
+static void
+da_activate(struct FsmInst *fi, int event, void *arg)
+{
+	struct manager	*mgr = fi->userdata;
+
+	if (fi->state == ST_L1_DEACT_PENDING)
+		mISDN_FsmDelTimer(&mgr->datimer, 1);
+	mISDN_FsmChangeState(fi, ST_L1_ACTIV);
+}
+
+static void
+da_deactivate_ind(struct FsmInst *fi, int event, void *arg)
+{
+	mISDN_FsmChangeState(fi, ST_L1_DEACT);
+}
+
+static void
+da_deactivate(struct FsmInst *fi, int event, void *arg)
+{
+	struct manager	*mgr = fi->userdata;
+	struct layer2	*l2;
+	u_long		flags;
+
+	read_lock_irqsave(&mgr->lock, flags);
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if (l2->l2m.state > ST_L2_4) {
+			/* have still activ TEI */
+			read_unlock_irqrestore(&mgr->lock, flags);
+			return;
+		}
+	}
+	read_unlock_irqrestore(&mgr->lock, flags);
+	/* All TEI are inactiv */
+	if (!test_bit(OPTION_L1_HOLD, &mgr->options)) {
+		mISDN_FsmAddTimer(&mgr->datimer, DATIMER_VAL, EV_DATIMER,
+				  NULL, 1);
+		mISDN_FsmChangeState(fi, ST_L1_DEACT_PENDING);
+	}
+}
+
+static void
+da_ui(struct FsmInst *fi, int event, void *arg)
+{
+	struct manager	*mgr = fi->userdata;
+
+	/* restart da timer */
+	if (!test_bit(OPTION_L1_HOLD, &mgr->options)) {
+		mISDN_FsmDelTimer(&mgr->datimer, 2);
+		mISDN_FsmAddTimer(&mgr->datimer, DATIMER_VAL, EV_DATIMER,
+				  NULL, 2);
+	}
+}
+
+static void
+da_timer(struct FsmInst *fi, int event, void *arg)
+{
+	struct manager	*mgr = fi->userdata;
+	struct layer2	*l2;
+	u_long		flags;
+
+	/* check again */
+	read_lock_irqsave(&mgr->lock, flags);
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if (l2->l2m.state > ST_L2_4) {
+			/* have still activ TEI */
+			read_unlock_irqrestore(&mgr->lock, flags);
+			mISDN_FsmChangeState(fi, ST_L1_ACTIV);
+			return;
+		}
+	}
+	read_unlock_irqrestore(&mgr->lock, flags);
+	/* All TEI are inactiv */
+	mISDN_FsmChangeState(fi, ST_L1_DEACT);
+	_queue_data(&mgr->ch, PH_DEACTIVATE_REQ, MISDN_ID_ANY, 0, NULL,
+		    GFP_ATOMIC);
+}
+
+static struct FsmNode DeactFnList[] =
+{
+	{ST_L1_DEACT, EV_ACTIVATE_IND, da_activate},
+	{ST_L1_ACTIV, EV_DEACTIVATE_IND, da_deactivate_ind},
+	{ST_L1_ACTIV, EV_DEACTIVATE, da_deactivate},
+	{ST_L1_DEACT_PENDING, EV_ACTIVATE, da_activate},
+	{ST_L1_DEACT_PENDING, EV_UI, da_ui},
+	{ST_L1_DEACT_PENDING, EV_DATIMER, da_timer},
+};
+
+enum {
+	ST_TEI_NOP,
+	ST_TEI_IDREQ,
+	ST_TEI_IDVERIFY,
+};
+
+#define TEI_STATE_COUNT (ST_TEI_IDVERIFY + 1)
+
+static char *strTeiState[] =
+{
+	"ST_TEI_NOP",
+	"ST_TEI_IDREQ",
+	"ST_TEI_IDVERIFY",
+};
+
+enum {
+	EV_IDREQ,
+	EV_ASSIGN,
+	EV_ASSIGN_REQ,
+	EV_DENIED,
+	EV_CHKREQ,
+	EV_CHKRESP,
+	EV_REMOVE,
+	EV_VERIFY,
+	EV_TIMER,
+};
+
+#define TEI_EVENT_COUNT (EV_TIMER + 1)
+
+static char *strTeiEvent[] =
+{
+	"EV_IDREQ",
+	"EV_ASSIGN",
+	"EV_ASSIGN_REQ",
+	"EV_DENIED",
+	"EV_CHKREQ",
+	"EV_CHKRESP",
+	"EV_REMOVE",
+	"EV_VERIFY",
+	"EV_TIMER",
+};
+
+static void
+tei_debug(struct FsmInst *fi, char *fmt, ...)
+{
+	struct teimgr	*tm = fi->userdata;
+	struct va_format vaf;
+	va_list va;
+
+	if (!(*debug & DEBUG_L2_TEIFSM))
+		return;
+
+	va_start(va, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "sapi(%d) tei(%d): %pV\n",
+	       tm->l2->sapi, tm->l2->tei, &vaf);
+
+	va_end(va);
+}
+
+
+
+static int
+get_free_id(struct manager *mgr)
+{
+	DECLARE_BITMAP(ids, 64) = { [0 ... BITS_TO_LONGS(64) - 1] = 0 };
+	int		i;
+	struct layer2	*l2;
+
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if (l2->ch.nr > 63) {
+			printk(KERN_WARNING
+			       "%s: more as 63 layer2 for one device\n",
+			       __func__);
+			return -EBUSY;
+		}
+		__set_bit(l2->ch.nr, ids);
+	}
+	i = find_next_zero_bit(ids, 64, 1);
+	if (i < 64)
+		return i;
+	printk(KERN_WARNING "%s: more as 63 layer2 for one device\n",
+	       __func__);
+	return -EBUSY;
+}
+
+static int
+get_free_tei(struct manager *mgr)
+{
+	DECLARE_BITMAP(ids, 64) = { [0 ... BITS_TO_LONGS(64) - 1] = 0 };
+	int		i;
+	struct layer2	*l2;
+
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if (l2->ch.nr == 0)
+			continue;
+		if ((l2->ch.addr & 0xff) != 0)
+			continue;
+		i = l2->ch.addr >> 8;
+		if (i < 64)
+			continue;
+		i -= 64;
+
+		__set_bit(i, ids);
+	}
+	i = find_first_zero_bit(ids, 64);
+	if (i < 64)
+		return i + 64;
+	printk(KERN_WARNING "%s: more as 63 dynamic tei for one device\n",
+	       __func__);
+	return -1;
+}
+
+static void
+teiup_create(struct manager *mgr, u_int prim, int len, void *arg)
+{
+	struct sk_buff	*skb;
+	struct mISDNhead *hh;
+	int		err;
+
+	skb = mI_alloc_skb(len, GFP_ATOMIC);
+	if (!skb)
+		return;
+	hh = mISDN_HEAD_P(skb);
+	hh->prim = prim;
+	hh->id = (mgr->ch.nr << 16) | mgr->ch.addr;
+	if (len)
+		skb_put_data(skb, arg, len);
+	err = mgr->up->send(mgr->up, skb);
+	if (err) {
+		printk(KERN_WARNING "%s: err=%d\n", __func__, err);
+		dev_kfree_skb(skb);
+	}
+}
+
+static u_int
+new_id(struct manager *mgr)
+{
+	u_int	id;
+
+	id = mgr->nextid++;
+	if (id == 0x7fff)
+		mgr->nextid = 1;
+	id <<= 16;
+	id |= GROUP_TEI << 8;
+	id |= TEI_SAPI;
+	return id;
+}
+
+static void
+do_send(struct manager *mgr)
+{
+	if (!test_bit(MGR_PH_ACTIVE, &mgr->options))
+		return;
+
+	if (!test_and_set_bit(MGR_PH_NOTREADY, &mgr->options)) {
+		struct sk_buff	*skb = skb_dequeue(&mgr->sendq);
+
+		if (!skb) {
+			test_and_clear_bit(MGR_PH_NOTREADY, &mgr->options);
+			return;
+		}
+		mgr->lastid = mISDN_HEAD_ID(skb);
+		mISDN_FsmEvent(&mgr->deact, EV_UI, NULL);
+		if (mgr->ch.recv(mgr->ch.peer, skb)) {
+			dev_kfree_skb(skb);
+			test_and_clear_bit(MGR_PH_NOTREADY, &mgr->options);
+			mgr->lastid = MISDN_ID_NONE;
+		}
+	}
+}
+
+static void
+do_ack(struct manager *mgr, u_int id)
+{
+	if (test_bit(MGR_PH_NOTREADY, &mgr->options)) {
+		if (id == mgr->lastid) {
+			if (test_bit(MGR_PH_ACTIVE, &mgr->options)) {
+				struct sk_buff	*skb;
+
+				skb = skb_dequeue(&mgr->sendq);
+				if (skb) {
+					mgr->lastid = mISDN_HEAD_ID(skb);
+					if (!mgr->ch.recv(mgr->ch.peer, skb))
+						return;
+					dev_kfree_skb(skb);
+				}
+			}
+			mgr->lastid = MISDN_ID_NONE;
+			test_and_clear_bit(MGR_PH_NOTREADY, &mgr->options);
+		}
+	}
+}
+
+static void
+mgr_send_down(struct manager *mgr, struct sk_buff *skb)
+{
+	skb_queue_tail(&mgr->sendq, skb);
+	if (!test_bit(MGR_PH_ACTIVE, &mgr->options)) {
+		_queue_data(&mgr->ch, PH_ACTIVATE_REQ, MISDN_ID_ANY, 0,
+			    NULL, GFP_KERNEL);
+	} else {
+		do_send(mgr);
+	}
+}
+
+static int
+dl_unit_data(struct manager *mgr, struct sk_buff *skb)
+{
+	if (!test_bit(MGR_OPT_NETWORK, &mgr->options)) /* only net send UI */
+		return -EINVAL;
+	if (!test_bit(MGR_PH_ACTIVE, &mgr->options))
+		_queue_data(&mgr->ch, PH_ACTIVATE_REQ, MISDN_ID_ANY, 0,
+			    NULL, GFP_KERNEL);
+	skb_push(skb, 3);
+	skb->data[0] = 0x02; /* SAPI 0 C/R = 1 */
+	skb->data[1] = 0xff; /* TEI 127 */
+	skb->data[2] = UI;   /* UI frame */
+	mISDN_HEAD_PRIM(skb) = PH_DATA_REQ;
+	mISDN_HEAD_ID(skb) = new_id(mgr);
+	skb_queue_tail(&mgr->sendq, skb);
+	do_send(mgr);
+	return 0;
+}
+
+static unsigned int
+random_ri(void)
+{
+	u16 x;
+
+	get_random_bytes(&x, sizeof(x));
+	return x;
+}
+
+static struct layer2 *
+findtei(struct manager *mgr, int tei)
+{
+	struct layer2	*l2;
+	u_long		flags;
+
+	read_lock_irqsave(&mgr->lock, flags);
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if ((l2->sapi == 0) && (l2->tei > 0) &&
+		    (l2->tei != GROUP_TEI) && (l2->tei == tei))
+			goto done;
+	}
+	l2 = NULL;
+done:
+	read_unlock_irqrestore(&mgr->lock, flags);
+	return l2;
+}
+
+static void
+put_tei_msg(struct manager *mgr, u_char m_id, unsigned int ri, int tei)
+{
+	struct sk_buff *skb;
+	u_char bp[8];
+
+	bp[0] = (TEI_SAPI << 2);
+	if (test_bit(MGR_OPT_NETWORK, &mgr->options))
+		bp[0] |= 2; /* CR:=1 for net command */
+	bp[1] = (GROUP_TEI << 1) | 0x1;
+	bp[2] = UI;
+	bp[3] = TEI_ENTITY_ID;
+	bp[4] = ri >> 8;
+	bp[5] = ri & 0xff;
+	bp[6] = m_id;
+	bp[7] = ((tei << 1) & 0xff) | 1;
+	skb = _alloc_mISDN_skb(PH_DATA_REQ, new_id(mgr), 8, bp, GFP_ATOMIC);
+	if (!skb) {
+		printk(KERN_WARNING "%s: no skb for tei msg\n", __func__);
+		return;
+	}
+	mgr_send_down(mgr, skb);
+}
+
+static void
+tei_id_request(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+
+	if (tm->l2->tei != GROUP_TEI) {
+		tm->tei_m.printdebug(&tm->tei_m,
+				     "assign request for already assigned tei %d",
+				     tm->l2->tei);
+		return;
+	}
+	tm->ri = random_ri();
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(&tm->tei_m,
+				     "assign request ri %d", tm->ri);
+	put_tei_msg(tm->mgr, ID_REQUEST, tm->ri, GROUP_TEI);
+	mISDN_FsmChangeState(fi, ST_TEI_IDREQ);
+	mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 1);
+	tm->nval = 3;
+}
+
+static void
+tei_id_assign(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr	*tm = fi->userdata;
+	struct layer2	*l2;
+	u_char *dp = arg;
+	int ri, tei;
+
+	ri = ((unsigned int) *dp++ << 8);
+	ri += *dp++;
+	dp++;
+	tei = *dp >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity assign ri %d tei %d",
+				     ri, tei);
+	l2 = findtei(tm->mgr, tei);
+	if (l2) {	/* same tei is in use */
+		if (ri != l2->tm->ri) {
+			tm->tei_m.printdebug(fi,
+					     "possible duplicate assignment tei %d", tei);
+			tei_l2(l2, MDL_ERROR_RSP, 0);
+		}
+	} else if (ri == tm->ri) {
+		mISDN_FsmDelTimer(&tm->timer, 1);
+		mISDN_FsmChangeState(fi, ST_TEI_NOP);
+		tei_l2(tm->l2, MDL_ASSIGN_REQ, tei);
+	}
+}
+
+static void
+tei_id_test_dup(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr	*tm = fi->userdata;
+	struct layer2	*l2;
+	u_char *dp = arg;
+	int tei, ri;
+
+	ri = ((unsigned int) *dp++ << 8);
+	ri += *dp++;
+	dp++;
+	tei = *dp >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "foreign identity assign ri %d tei %d",
+				     ri, tei);
+	l2 = findtei(tm->mgr, tei);
+	if (l2) {	/* same tei is in use */
+		if (ri != l2->tm->ri) {	/* and it wasn't our request */
+			tm->tei_m.printdebug(fi,
+					     "possible duplicate assignment tei %d", tei);
+			mISDN_FsmEvent(&l2->tm->tei_m, EV_VERIFY, NULL);
+		}
+	}
+}
+
+static void
+tei_id_denied(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+	int ri, tei;
+
+	ri = ((unsigned int) *dp++ << 8);
+	ri += *dp++;
+	dp++;
+	tei = *dp >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity denied ri %d tei %d",
+				     ri, tei);
+}
+
+static void
+tei_id_chk_req(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+	int tei;
+
+	tei = *(dp + 3) >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity check req tei %d", tei);
+	if ((tm->l2->tei != GROUP_TEI) && ((tei == GROUP_TEI) ||
+					   (tei == tm->l2->tei))) {
+		mISDN_FsmDelTimer(&tm->timer, 4);
+		mISDN_FsmChangeState(&tm->tei_m, ST_TEI_NOP);
+		put_tei_msg(tm->mgr, ID_CHK_RES, random_ri(), tm->l2->tei);
+	}
+}
+
+static void
+tei_id_remove(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+	int tei;
+
+	tei = *(dp + 3) >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity remove tei %d", tei);
+	if ((tm->l2->tei != GROUP_TEI) &&
+	    ((tei == GROUP_TEI) || (tei == tm->l2->tei))) {
+		mISDN_FsmDelTimer(&tm->timer, 5);
+		mISDN_FsmChangeState(&tm->tei_m, ST_TEI_NOP);
+		tei_l2(tm->l2, MDL_REMOVE_REQ, 0);
+	}
+}
+
+static void
+tei_id_verify(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "id verify request for tei %d",
+				     tm->l2->tei);
+	put_tei_msg(tm->mgr, ID_VERIFY, 0, tm->l2->tei);
+	mISDN_FsmChangeState(&tm->tei_m, ST_TEI_IDVERIFY);
+	mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 2);
+	tm->nval = 2;
+}
+
+static void
+tei_id_req_tout(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+
+	if (--tm->nval) {
+		tm->ri = random_ri();
+		if (*debug & DEBUG_L2_TEI)
+			tm->tei_m.printdebug(fi, "assign req(%d) ri %d",
+					     4 - tm->nval, tm->ri);
+		put_tei_msg(tm->mgr, ID_REQUEST, tm->ri, GROUP_TEI);
+		mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 3);
+	} else {
+		tm->tei_m.printdebug(fi, "assign req failed");
+		tei_l2(tm->l2, MDL_ERROR_RSP, 0);
+		mISDN_FsmChangeState(fi, ST_TEI_NOP);
+	}
+}
+
+static void
+tei_id_ver_tout(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+
+	if (--tm->nval) {
+		if (*debug & DEBUG_L2_TEI)
+			tm->tei_m.printdebug(fi,
+					     "id verify req(%d) for tei %d",
+					     3 - tm->nval, tm->l2->tei);
+		put_tei_msg(tm->mgr, ID_VERIFY, 0, tm->l2->tei);
+		mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 4);
+	} else {
+		tm->tei_m.printdebug(fi, "verify req for tei %d failed",
+				     tm->l2->tei);
+		tei_l2(tm->l2, MDL_REMOVE_REQ, 0);
+		mISDN_FsmChangeState(fi, ST_TEI_NOP);
+	}
+}
+
+static struct FsmNode TeiFnListUser[] =
+{
+	{ST_TEI_NOP, EV_IDREQ, tei_id_request},
+	{ST_TEI_NOP, EV_ASSIGN, tei_id_test_dup},
+	{ST_TEI_NOP, EV_VERIFY, tei_id_verify},
+	{ST_TEI_NOP, EV_REMOVE, tei_id_remove},
+	{ST_TEI_NOP, EV_CHKREQ, tei_id_chk_req},
+	{ST_TEI_IDREQ, EV_TIMER, tei_id_req_tout},
+	{ST_TEI_IDREQ, EV_ASSIGN, tei_id_assign},
+	{ST_TEI_IDREQ, EV_DENIED, tei_id_denied},
+	{ST_TEI_IDVERIFY, EV_TIMER, tei_id_ver_tout},
+	{ST_TEI_IDVERIFY, EV_REMOVE, tei_id_remove},
+	{ST_TEI_IDVERIFY, EV_CHKREQ, tei_id_chk_req},
+};
+
+static void
+tei_l2remove(struct layer2 *l2)
+{
+	put_tei_msg(l2->tm->mgr, ID_REMOVE, 0, l2->tei);
+	tei_l2(l2, MDL_REMOVE_REQ, 0);
+	list_del(&l2->ch.list);
+	l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+}
+
+static void
+tei_assign_req(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+
+	if (tm->l2->tei == GROUP_TEI) {
+		tm->tei_m.printdebug(&tm->tei_m,
+				     "net tei assign request without tei");
+		return;
+	}
+	tm->ri = ((unsigned int) *dp++ << 8);
+	tm->ri += *dp++;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(&tm->tei_m,
+				     "net assign request ri %d teim %d", tm->ri, *dp);
+	put_tei_msg(tm->mgr, ID_ASSIGNED, tm->ri, tm->l2->tei);
+	mISDN_FsmChangeState(fi, ST_TEI_NOP);
+}
+
+static void
+tei_id_chk_req_net(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr	*tm = fi->userdata;
+
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "id check request for tei %d",
+				     tm->l2->tei);
+	tm->rcnt = 0;
+	put_tei_msg(tm->mgr, ID_CHK_REQ, 0, tm->l2->tei);
+	mISDN_FsmChangeState(&tm->tei_m, ST_TEI_IDVERIFY);
+	mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 2);
+	tm->nval = 2;
+}
+
+static void
+tei_id_chk_resp(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+	int tei;
+
+	tei = dp[3] >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity check resp tei %d", tei);
+	if (tei == tm->l2->tei)
+		tm->rcnt++;
+}
+
+static void
+tei_id_verify_net(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+	u_char *dp = arg;
+	int tei;
+
+	tei = dp[3] >> 1;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(fi, "identity verify req tei %d/%d",
+				     tei, tm->l2->tei);
+	if (tei == tm->l2->tei)
+		tei_id_chk_req_net(fi, event, arg);
+}
+
+static void
+tei_id_ver_tout_net(struct FsmInst *fi, int event, void *arg)
+{
+	struct teimgr *tm = fi->userdata;
+
+	if (tm->rcnt == 1) {
+		if (*debug & DEBUG_L2_TEI)
+			tm->tei_m.printdebug(fi,
+					     "check req for tei %d successful\n", tm->l2->tei);
+		mISDN_FsmChangeState(fi, ST_TEI_NOP);
+	} else if (tm->rcnt > 1) {
+		/* duplicate assignment; remove */
+		tei_l2remove(tm->l2);
+	} else if (--tm->nval) {
+		if (*debug & DEBUG_L2_TEI)
+			tm->tei_m.printdebug(fi,
+					     "id check req(%d) for tei %d",
+					     3 - tm->nval, tm->l2->tei);
+		put_tei_msg(tm->mgr, ID_CHK_REQ, 0, tm->l2->tei);
+		mISDN_FsmAddTimer(&tm->timer, tm->tval, EV_TIMER, NULL, 4);
+	} else {
+		tm->tei_m.printdebug(fi, "check req for tei %d failed",
+				     tm->l2->tei);
+		mISDN_FsmChangeState(fi, ST_TEI_NOP);
+		tei_l2remove(tm->l2);
+	}
+}
+
+static struct FsmNode TeiFnListNet[] =
+{
+	{ST_TEI_NOP, EV_ASSIGN_REQ, tei_assign_req},
+	{ST_TEI_NOP, EV_VERIFY, tei_id_verify_net},
+	{ST_TEI_NOP, EV_CHKREQ, tei_id_chk_req_net},
+	{ST_TEI_IDVERIFY, EV_TIMER, tei_id_ver_tout_net},
+	{ST_TEI_IDVERIFY, EV_CHKRESP, tei_id_chk_resp},
+};
+
+static void
+tei_ph_data_ind(struct teimgr *tm, u_int mt, u_char *dp, int len)
+{
+	if (test_bit(FLG_FIXED_TEI, &tm->l2->flag))
+		return;
+	if (*debug & DEBUG_L2_TEI)
+		tm->tei_m.printdebug(&tm->tei_m, "tei handler mt %x", mt);
+	if (mt == ID_ASSIGNED)
+		mISDN_FsmEvent(&tm->tei_m, EV_ASSIGN, dp);
+	else if (mt == ID_DENIED)
+		mISDN_FsmEvent(&tm->tei_m, EV_DENIED, dp);
+	else if (mt == ID_CHK_REQ)
+		mISDN_FsmEvent(&tm->tei_m, EV_CHKREQ, dp);
+	else if (mt == ID_REMOVE)
+		mISDN_FsmEvent(&tm->tei_m, EV_REMOVE, dp);
+	else if (mt == ID_VERIFY)
+		mISDN_FsmEvent(&tm->tei_m, EV_VERIFY, dp);
+	else if (mt == ID_CHK_RES)
+		mISDN_FsmEvent(&tm->tei_m, EV_CHKRESP, dp);
+}
+
+static struct layer2 *
+create_new_tei(struct manager *mgr, int tei, int sapi)
+{
+	unsigned long		opt = 0;
+	unsigned long		flags;
+	int			id;
+	struct layer2		*l2;
+	struct channel_req	rq;
+
+	if (!mgr->up)
+		return NULL;
+	if ((tei >= 0) && (tei < 64))
+		test_and_set_bit(OPTION_L2_FIXEDTEI, &opt);
+	if (mgr->ch.st->dev->Dprotocols & ((1 << ISDN_P_TE_E1) |
+	    (1 << ISDN_P_NT_E1))) {
+		test_and_set_bit(OPTION_L2_PMX, &opt);
+		rq.protocol = ISDN_P_NT_E1;
+	} else {
+		rq.protocol = ISDN_P_NT_S0;
+	}
+	l2 = create_l2(mgr->up, ISDN_P_LAPD_NT, opt, tei, sapi);
+	if (!l2) {
+		printk(KERN_WARNING "%s:no memory for layer2\n", __func__);
+		return NULL;
+	}
+	l2->tm = kzalloc(sizeof(struct teimgr), GFP_KERNEL);
+	if (!l2->tm) {
+		kfree(l2);
+		printk(KERN_WARNING "%s:no memory for teimgr\n", __func__);
+		return NULL;
+	}
+	l2->tm->mgr = mgr;
+	l2->tm->l2 = l2;
+	l2->tm->tei_m.debug = *debug & DEBUG_L2_TEIFSM;
+	l2->tm->tei_m.userdata = l2->tm;
+	l2->tm->tei_m.printdebug = tei_debug;
+	l2->tm->tei_m.fsm = &teifsmn;
+	l2->tm->tei_m.state = ST_TEI_NOP;
+	l2->tm->tval = 2000; /* T202  2 sec */
+	mISDN_FsmInitTimer(&l2->tm->tei_m, &l2->tm->timer);
+	write_lock_irqsave(&mgr->lock, flags);
+	id = get_free_id(mgr);
+	list_add_tail(&l2->list, &mgr->layer2);
+	write_unlock_irqrestore(&mgr->lock, flags);
+	if (id < 0) {
+		l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+		printk(KERN_WARNING "%s:no free id\n", __func__);
+		return NULL;
+	} else {
+		l2->ch.nr = id;
+		__add_layer2(&l2->ch, mgr->ch.st);
+		l2->ch.recv = mgr->ch.recv;
+		l2->ch.peer = mgr->ch.peer;
+		l2->ch.ctrl(&l2->ch, OPEN_CHANNEL, NULL);
+		/* We need open here L1 for the manager as well (refcounting) */
+		rq.adr.dev = mgr->ch.st->dev->id;
+		id = mgr->ch.st->own.ctrl(&mgr->ch.st->own, OPEN_CHANNEL, &rq);
+		if (id < 0) {
+			printk(KERN_WARNING "%s: cannot open L1\n", __func__);
+			l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+			l2 = NULL;
+		}
+	}
+	return l2;
+}
+
+static void
+new_tei_req(struct manager *mgr, u_char *dp)
+{
+	int		tei, ri;
+	struct layer2	*l2;
+
+	ri = dp[0] << 8;
+	ri += dp[1];
+	if (!mgr->up)
+		goto denied;
+	if (!(dp[3] & 1)) /* Extension bit != 1 */
+		goto denied;
+	if (dp[3] != 0xff)
+		tei = dp[3] >> 1; /* 3GPP TS 08.56 6.1.11.2 */
+	else
+		tei = get_free_tei(mgr);
+	if (tei < 0) {
+		printk(KERN_WARNING "%s:No free tei\n", __func__);
+		goto denied;
+	}
+	l2 = create_new_tei(mgr, tei, CTRL_SAPI);
+	if (!l2)
+		goto denied;
+	else
+		mISDN_FsmEvent(&l2->tm->tei_m, EV_ASSIGN_REQ, dp);
+	return;
+denied:
+	put_tei_msg(mgr, ID_DENIED, ri, GROUP_TEI);
+}
+
+static int
+ph_data_ind(struct manager *mgr, struct sk_buff *skb)
+{
+	int		ret = -EINVAL;
+	struct layer2	*l2, *nl2;
+	u_char		mt;
+
+	if (skb->len < 8) {
+		if (*debug  & DEBUG_L2_TEI)
+			printk(KERN_DEBUG "%s: short mgr frame %d/8\n",
+			       __func__, skb->len);
+		goto done;
+	}
+
+	if ((skb->data[0] >> 2) != TEI_SAPI) /* not for us */
+		goto done;
+	if (skb->data[0] & 1) /* EA0 formal error */
+		goto done;
+	if (!(skb->data[1] & 1)) /* EA1 formal error */
+		goto done;
+	if ((skb->data[1] >> 1) != GROUP_TEI) /* not for us */
+		goto done;
+	if ((skb->data[2] & 0xef) != UI) /* not UI */
+		goto done;
+	if (skb->data[3] != TEI_ENTITY_ID) /* not tei entity */
+		goto done;
+	mt = skb->data[6];
+	switch (mt) {
+	case ID_REQUEST:
+	case ID_CHK_RES:
+	case ID_VERIFY:
+		if (!test_bit(MGR_OPT_NETWORK, &mgr->options))
+			goto done;
+		break;
+	case ID_ASSIGNED:
+	case ID_DENIED:
+	case ID_CHK_REQ:
+	case ID_REMOVE:
+		if (test_bit(MGR_OPT_NETWORK, &mgr->options))
+			goto done;
+		break;
+	default:
+		goto done;
+	}
+	ret = 0;
+	if (mt == ID_REQUEST) {
+		new_tei_req(mgr, &skb->data[4]);
+		goto done;
+	}
+	list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) {
+		tei_ph_data_ind(l2->tm, mt, &skb->data[4], skb->len - 4);
+	}
+done:
+	return ret;
+}
+
+int
+l2_tei(struct layer2 *l2, u_int cmd, u_long arg)
+{
+	struct teimgr	*tm = l2->tm;
+
+	if (test_bit(FLG_FIXED_TEI, &l2->flag))
+		return 0;
+	if (*debug & DEBUG_L2_TEI)
+		printk(KERN_DEBUG "%s: cmd(%x)\n", __func__, cmd);
+	switch (cmd) {
+	case MDL_ASSIGN_IND:
+		mISDN_FsmEvent(&tm->tei_m, EV_IDREQ, NULL);
+		break;
+	case MDL_ERROR_IND:
+		if (test_bit(MGR_OPT_NETWORK, &tm->mgr->options))
+			mISDN_FsmEvent(&tm->tei_m, EV_CHKREQ, &l2->tei);
+		if (test_bit(MGR_OPT_USER, &tm->mgr->options))
+			mISDN_FsmEvent(&tm->tei_m, EV_VERIFY, NULL);
+		break;
+	case MDL_STATUS_UP_IND:
+		if (test_bit(MGR_OPT_NETWORK, &tm->mgr->options))
+			mISDN_FsmEvent(&tm->mgr->deact, EV_ACTIVATE, NULL);
+		break;
+	case MDL_STATUS_DOWN_IND:
+		if (test_bit(MGR_OPT_NETWORK, &tm->mgr->options))
+			mISDN_FsmEvent(&tm->mgr->deact, EV_DEACTIVATE, NULL);
+		break;
+	case MDL_STATUS_UI_IND:
+		if (test_bit(MGR_OPT_NETWORK, &tm->mgr->options))
+			mISDN_FsmEvent(&tm->mgr->deact, EV_UI, NULL);
+		break;
+	}
+	return 0;
+}
+
+void
+TEIrelease(struct layer2 *l2)
+{
+	struct teimgr	*tm = l2->tm;
+	u_long		flags;
+
+	mISDN_FsmDelTimer(&tm->timer, 1);
+	write_lock_irqsave(&tm->mgr->lock, flags);
+	list_del(&l2->list);
+	write_unlock_irqrestore(&tm->mgr->lock, flags);
+	l2->tm = NULL;
+	kfree(tm);
+}
+
+static int
+create_teimgr(struct manager *mgr, struct channel_req *crq)
+{
+	struct layer2		*l2;
+	unsigned long		opt = 0;
+	unsigned long		flags;
+	int			id;
+	struct channel_req	l1rq;
+
+	if (*debug & DEBUG_L2_TEI)
+		printk(KERN_DEBUG "%s: %s proto(%x) adr(%d %d %d %d)\n",
+		       __func__, dev_name(&mgr->ch.st->dev->dev),
+		       crq->protocol, crq->adr.dev, crq->adr.channel,
+		       crq->adr.sapi, crq->adr.tei);
+	if (crq->adr.tei > GROUP_TEI)
+		return -EINVAL;
+	if (crq->adr.tei < 64)
+		test_and_set_bit(OPTION_L2_FIXEDTEI, &opt);
+	if (crq->adr.tei == 0)
+		test_and_set_bit(OPTION_L2_PTP, &opt);
+	if (test_bit(MGR_OPT_NETWORK, &mgr->options)) {
+		if (crq->protocol == ISDN_P_LAPD_TE)
+			return -EPROTONOSUPPORT;
+		if ((crq->adr.tei != 0) && (crq->adr.tei != 127))
+			return -EINVAL;
+		if (mgr->up) {
+			printk(KERN_WARNING
+			       "%s: only one network manager is allowed\n",
+			       __func__);
+			return -EBUSY;
+		}
+	} else if (test_bit(MGR_OPT_USER, &mgr->options)) {
+		if (crq->protocol == ISDN_P_LAPD_NT)
+			return -EPROTONOSUPPORT;
+		if ((crq->adr.tei >= 64) && (crq->adr.tei < GROUP_TEI))
+			return -EINVAL; /* dyn tei */
+	} else {
+		if (crq->protocol == ISDN_P_LAPD_NT)
+			test_and_set_bit(MGR_OPT_NETWORK, &mgr->options);
+		if (crq->protocol == ISDN_P_LAPD_TE)
+			test_and_set_bit(MGR_OPT_USER, &mgr->options);
+	}
+	l1rq.adr = crq->adr;
+	if (mgr->ch.st->dev->Dprotocols
+	    & ((1 << ISDN_P_TE_E1) | (1 << ISDN_P_NT_E1)))
+		test_and_set_bit(OPTION_L2_PMX, &opt);
+	if ((crq->protocol == ISDN_P_LAPD_NT) && (crq->adr.tei == 127)) {
+		mgr->up = crq->ch;
+		id = DL_INFO_L2_CONNECT;
+		teiup_create(mgr, DL_INFORMATION_IND, sizeof(id), &id);
+		if (test_bit(MGR_PH_ACTIVE, &mgr->options))
+			teiup_create(mgr, PH_ACTIVATE_IND, 0, NULL);
+		crq->ch = NULL;
+		if (!list_empty(&mgr->layer2)) {
+			read_lock_irqsave(&mgr->lock, flags);
+			list_for_each_entry(l2, &mgr->layer2, list) {
+				l2->up = mgr->up;
+				l2->ch.ctrl(&l2->ch, OPEN_CHANNEL, NULL);
+			}
+			read_unlock_irqrestore(&mgr->lock, flags);
+		}
+		return 0;
+	}
+	l2 = create_l2(crq->ch, crq->protocol, opt,
+		       crq->adr.tei, crq->adr.sapi);
+	if (!l2)
+		return -ENOMEM;
+	l2->tm = kzalloc(sizeof(struct teimgr), GFP_KERNEL);
+	if (!l2->tm) {
+		kfree(l2);
+		printk(KERN_ERR "kmalloc teimgr failed\n");
+		return -ENOMEM;
+	}
+	l2->tm->mgr = mgr;
+	l2->tm->l2 = l2;
+	l2->tm->tei_m.debug = *debug & DEBUG_L2_TEIFSM;
+	l2->tm->tei_m.userdata = l2->tm;
+	l2->tm->tei_m.printdebug = tei_debug;
+	if (crq->protocol == ISDN_P_LAPD_TE) {
+		l2->tm->tei_m.fsm = &teifsmu;
+		l2->tm->tei_m.state = ST_TEI_NOP;
+		l2->tm->tval = 1000; /* T201  1 sec */
+		if (test_bit(OPTION_L2_PMX, &opt))
+			l1rq.protocol = ISDN_P_TE_E1;
+		else
+			l1rq.protocol = ISDN_P_TE_S0;
+	} else {
+		l2->tm->tei_m.fsm = &teifsmn;
+		l2->tm->tei_m.state = ST_TEI_NOP;
+		l2->tm->tval = 2000; /* T202  2 sec */
+		if (test_bit(OPTION_L2_PMX, &opt))
+			l1rq.protocol = ISDN_P_NT_E1;
+		else
+			l1rq.protocol = ISDN_P_NT_S0;
+	}
+	mISDN_FsmInitTimer(&l2->tm->tei_m, &l2->tm->timer);
+	write_lock_irqsave(&mgr->lock, flags);
+	id = get_free_id(mgr);
+	list_add_tail(&l2->list, &mgr->layer2);
+	write_unlock_irqrestore(&mgr->lock, flags);
+	if (id >= 0) {
+		l2->ch.nr = id;
+		l2->up->nr = id;
+		crq->ch = &l2->ch;
+		/* We need open here L1 for the manager as well (refcounting) */
+		id = mgr->ch.st->own.ctrl(&mgr->ch.st->own, OPEN_CHANNEL,
+					  &l1rq);
+	}
+	if (id < 0)
+		l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+	return id;
+}
+
+static int
+mgr_send(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct manager	*mgr;
+	struct mISDNhead	*hh =  mISDN_HEAD_P(skb);
+	int			ret = -EINVAL;
+
+	mgr = container_of(ch, struct manager, ch);
+	if (*debug & DEBUG_L2_RECV)
+		printk(KERN_DEBUG "%s: prim(%x) id(%x)\n",
+		       __func__, hh->prim, hh->id);
+	switch (hh->prim) {
+	case PH_DATA_IND:
+		mISDN_FsmEvent(&mgr->deact, EV_UI, NULL);
+		ret = ph_data_ind(mgr, skb);
+		break;
+	case PH_DATA_CNF:
+		do_ack(mgr, hh->id);
+		ret = 0;
+		break;
+	case PH_ACTIVATE_IND:
+		test_and_set_bit(MGR_PH_ACTIVE, &mgr->options);
+		if (mgr->up)
+			teiup_create(mgr, PH_ACTIVATE_IND, 0, NULL);
+		mISDN_FsmEvent(&mgr->deact, EV_ACTIVATE_IND, NULL);
+		do_send(mgr);
+		ret = 0;
+		break;
+	case PH_DEACTIVATE_IND:
+		test_and_clear_bit(MGR_PH_ACTIVE, &mgr->options);
+		if (mgr->up)
+			teiup_create(mgr, PH_DEACTIVATE_IND, 0, NULL);
+		mISDN_FsmEvent(&mgr->deact, EV_DEACTIVATE_IND, NULL);
+		ret = 0;
+		break;
+	case DL_UNITDATA_REQ:
+		return dl_unit_data(mgr, skb);
+	}
+	if (!ret)
+		dev_kfree_skb(skb);
+	return ret;
+}
+
+static int
+free_teimanager(struct manager *mgr)
+{
+	struct layer2	*l2, *nl2;
+
+	test_and_clear_bit(OPTION_L1_HOLD, &mgr->options);
+	if (test_bit(MGR_OPT_NETWORK, &mgr->options)) {
+		/* not locked lock is taken in release tei */
+		mgr->up = NULL;
+		if (test_bit(OPTION_L2_CLEANUP, &mgr->options)) {
+			list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) {
+				put_tei_msg(mgr, ID_REMOVE, 0, l2->tei);
+				mutex_lock(&mgr->ch.st->lmutex);
+				list_del(&l2->ch.list);
+				mutex_unlock(&mgr->ch.st->lmutex);
+				l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+			}
+			test_and_clear_bit(MGR_OPT_NETWORK, &mgr->options);
+		} else {
+			list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) {
+				l2->up = NULL;
+			}
+		}
+	}
+	if (test_bit(MGR_OPT_USER, &mgr->options)) {
+		if (list_empty(&mgr->layer2))
+			test_and_clear_bit(MGR_OPT_USER, &mgr->options);
+	}
+	mgr->ch.st->dev->D.ctrl(&mgr->ch.st->dev->D, CLOSE_CHANNEL, NULL);
+	return 0;
+}
+
+static int
+ctrl_teimanager(struct manager *mgr, void *arg)
+{
+	/* currently we only have one option */
+	unsigned int *val = (unsigned int *)arg;
+
+	switch (val[0]) {
+	case IMCLEAR_L2:
+		if (val[1])
+			test_and_set_bit(OPTION_L2_CLEANUP, &mgr->options);
+		else
+			test_and_clear_bit(OPTION_L2_CLEANUP, &mgr->options);
+		break;
+	case IMHOLD_L1:
+		if (val[1])
+			test_and_set_bit(OPTION_L1_HOLD, &mgr->options);
+		else
+			test_and_clear_bit(OPTION_L1_HOLD, &mgr->options);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/* This function does create a L2 for fixed TEI in NT Mode */
+static int
+check_data(struct manager *mgr, struct sk_buff *skb)
+{
+	struct mISDNhead	*hh =  mISDN_HEAD_P(skb);
+	int			ret, tei, sapi;
+	struct layer2		*l2;
+
+	if (*debug & DEBUG_L2_CTRL)
+		printk(KERN_DEBUG "%s: prim(%x) id(%x)\n",
+		       __func__, hh->prim, hh->id);
+	if (test_bit(MGR_OPT_USER, &mgr->options))
+		return -ENOTCONN;
+	if (hh->prim != PH_DATA_IND)
+		return -ENOTCONN;
+	if (skb->len != 3)
+		return -ENOTCONN;
+	if (skb->data[0] & 3) /* EA0 and CR must be  0 */
+		return -EINVAL;
+	sapi = skb->data[0] >> 2;
+	if (!(skb->data[1] & 1)) /* invalid EA1 */
+		return -EINVAL;
+	tei = skb->data[1] >> 1;
+	if (tei > 63) /* not a fixed tei */
+		return -ENOTCONN;
+	if ((skb->data[2] & ~0x10) != SABME)
+		return -ENOTCONN;
+	/* We got a SABME for a fixed TEI */
+	if (*debug & DEBUG_L2_CTRL)
+		printk(KERN_DEBUG "%s: SABME sapi(%d) tei(%d)\n",
+		       __func__, sapi, tei);
+	l2 = create_new_tei(mgr, tei, sapi);
+	if (!l2) {
+		if (*debug & DEBUG_L2_CTRL)
+			printk(KERN_DEBUG "%s: failed to create new tei\n",
+			       __func__);
+		return -ENOMEM;
+	}
+	ret = l2->ch.send(&l2->ch, skb);
+	return ret;
+}
+
+void
+delete_teimanager(struct mISDNchannel *ch)
+{
+	struct manager	*mgr;
+	struct layer2	*l2, *nl2;
+
+	mgr = container_of(ch, struct manager, ch);
+	/* not locked lock is taken in release tei */
+	list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) {
+		mutex_lock(&mgr->ch.st->lmutex);
+		list_del(&l2->ch.list);
+		mutex_unlock(&mgr->ch.st->lmutex);
+		l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
+	}
+	list_del(&mgr->ch.list);
+	list_del(&mgr->bcast.list);
+	skb_queue_purge(&mgr->sendq);
+	kfree(mgr);
+}
+
+static int
+mgr_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+	struct manager	*mgr;
+	int		ret = -EINVAL;
+
+	mgr = container_of(ch, struct manager, ch);
+	if (*debug & DEBUG_L2_CTRL)
+		printk(KERN_DEBUG "%s(%x, %p)\n", __func__, cmd, arg);
+	switch (cmd) {
+	case OPEN_CHANNEL:
+		ret = create_teimgr(mgr, arg);
+		break;
+	case CLOSE_CHANNEL:
+		ret = free_teimanager(mgr);
+		break;
+	case CONTROL_CHANNEL:
+		ret = ctrl_teimanager(mgr, arg);
+		break;
+	case CHECK_DATA:
+		ret = check_data(mgr, arg);
+		break;
+	}
+	return ret;
+}
+
+static int
+mgr_bcast(struct mISDNchannel *ch, struct sk_buff *skb)
+{
+	struct manager		*mgr = container_of(ch, struct manager, bcast);
+	struct mISDNhead	*hhc, *hh = mISDN_HEAD_P(skb);
+	struct sk_buff		*cskb = NULL;
+	struct layer2		*l2;
+	u_long			flags;
+	int			ret;
+
+	read_lock_irqsave(&mgr->lock, flags);
+	list_for_each_entry(l2, &mgr->layer2, list) {
+		if ((hh->id & MISDN_ID_SAPI_MASK) ==
+		    (l2->ch.addr & MISDN_ID_SAPI_MASK)) {
+			if (list_is_last(&l2->list, &mgr->layer2)) {
+				cskb = skb;
+				skb = NULL;
+			} else {
+				if (!cskb)
+					cskb = skb_copy(skb, GFP_ATOMIC);
+			}
+			if (cskb) {
+				hhc = mISDN_HEAD_P(cskb);
+				/* save original header behind normal header */
+				hhc++;
+				*hhc = *hh;
+				hhc--;
+				hhc->prim = DL_INTERN_MSG;
+				hhc->id = l2->ch.nr;
+				ret = ch->st->own.recv(&ch->st->own, cskb);
+				if (ret) {
+					if (*debug & DEBUG_SEND_ERR)
+						printk(KERN_DEBUG
+						       "%s ch%d prim(%x) addr(%x)"
+						       " err %d\n",
+						       __func__, l2->ch.nr,
+						       hh->prim, l2->ch.addr, ret);
+				} else
+					cskb = NULL;
+			} else {
+				printk(KERN_WARNING "%s ch%d addr %x no mem\n",
+				       __func__, ch->nr, ch->addr);
+				goto out;
+			}
+		}
+	}
+out:
+	read_unlock_irqrestore(&mgr->lock, flags);
+	dev_kfree_skb(cskb);
+	dev_kfree_skb(skb);
+	return 0;
+}
+
+static int
+mgr_bcast_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
+{
+
+	return -EINVAL;
+}
+
+int
+create_teimanager(struct mISDNdevice *dev)
+{
+	struct manager *mgr;
+
+	mgr = kzalloc(sizeof(struct manager), GFP_KERNEL);
+	if (!mgr)
+		return -ENOMEM;
+	INIT_LIST_HEAD(&mgr->layer2);
+	rwlock_init(&mgr->lock);
+	skb_queue_head_init(&mgr->sendq);
+	mgr->nextid = 1;
+	mgr->lastid = MISDN_ID_NONE;
+	mgr->ch.send = mgr_send;
+	mgr->ch.ctrl = mgr_ctrl;
+	mgr->ch.st = dev->D.st;
+	set_channel_address(&mgr->ch, TEI_SAPI, GROUP_TEI);
+	add_layer2(&mgr->ch, dev->D.st);
+	mgr->bcast.send = mgr_bcast;
+	mgr->bcast.ctrl = mgr_bcast_ctrl;
+	mgr->bcast.st = dev->D.st;
+	set_channel_address(&mgr->bcast, 0, GROUP_TEI);
+	add_layer2(&mgr->bcast, dev->D.st);
+	mgr->deact.debug = *debug & DEBUG_MANAGER;
+	mgr->deact.userdata = mgr;
+	mgr->deact.printdebug = da_debug;
+	mgr->deact.fsm = &deactfsm;
+	mgr->deact.state = ST_L1_DEACT;
+	mISDN_FsmInitTimer(&mgr->deact, &mgr->datimer);
+	dev->teimgr = &mgr->ch;
+	return 0;
+}
+
+int TEIInit(u_int *deb)
+{
+	int res;
+	debug = deb;
+	teifsmu.state_count = TEI_STATE_COUNT;
+	teifsmu.event_count = TEI_EVENT_COUNT;
+	teifsmu.strEvent = strTeiEvent;
+	teifsmu.strState = strTeiState;
+	res = mISDN_FsmNew(&teifsmu, TeiFnListUser, ARRAY_SIZE(TeiFnListUser));
+	if (res)
+		goto error;
+	teifsmn.state_count = TEI_STATE_COUNT;
+	teifsmn.event_count = TEI_EVENT_COUNT;
+	teifsmn.strEvent = strTeiEvent;
+	teifsmn.strState = strTeiState;
+	res = mISDN_FsmNew(&teifsmn, TeiFnListNet, ARRAY_SIZE(TeiFnListNet));
+	if (res)
+		goto error_smn;
+	deactfsm.state_count =  DEACT_STATE_COUNT;
+	deactfsm.event_count = DEACT_EVENT_COUNT;
+	deactfsm.strEvent = strDeactEvent;
+	deactfsm.strState = strDeactState;
+	res = mISDN_FsmNew(&deactfsm, DeactFnList, ARRAY_SIZE(DeactFnList));
+	if (res)
+		goto error_deact;
+	return 0;
+
+error_deact:
+	mISDN_FsmFree(&teifsmn);
+error_smn:
+	mISDN_FsmFree(&teifsmu);
+error:
+	return res;
+}
+
+void TEIFree(void)
+{
+	mISDN_FsmFree(&teifsmu);
+	mISDN_FsmFree(&teifsmn);
+	mISDN_FsmFree(&deactfsm);
+}
diff --git a/drivers/isdn/mISDN/timerdev.c b/drivers/isdn/mISDN/timerdev.c
new file mode 100644
index 000000000..abdf36ac3
--- /dev/null
+++ b/drivers/isdn/mISDN/timerdev.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * general timer device for using in ISDN stacks
+ *
+ * Author	Karsten Keil <kkeil@novell.com>
+ *
+ * Copyright 2008  by Karsten Keil <kkeil@novell.com>
+ */
+
+#include <linux/poll.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mISDNif.h>
+#include <linux/mutex.h>
+#include <linux/sched/signal.h>
+
+#include "core.h"
+
+static DEFINE_MUTEX(mISDN_mutex);
+static u_int	*debug;
+
+
+struct mISDNtimerdev {
+	int			next_id;
+	struct list_head	pending;
+	struct list_head	expired;
+	wait_queue_head_t	wait;
+	u_int			work;
+	spinlock_t		lock; /* protect lists */
+};
+
+struct mISDNtimer {
+	struct list_head	list;
+	struct  mISDNtimerdev	*dev;
+	struct timer_list	tl;
+	int			id;
+};
+
+static int
+mISDN_open(struct inode *ino, struct file *filep)
+{
+	struct mISDNtimerdev	*dev;
+
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
+	dev = kmalloc(sizeof(struct mISDNtimerdev) , GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+	dev->next_id = 1;
+	INIT_LIST_HEAD(&dev->pending);
+	INIT_LIST_HEAD(&dev->expired);
+	spin_lock_init(&dev->lock);
+	dev->work = 0;
+	init_waitqueue_head(&dev->wait);
+	filep->private_data = dev;
+	return nonseekable_open(ino, filep);
+}
+
+static int
+mISDN_close(struct inode *ino, struct file *filep)
+{
+	struct mISDNtimerdev	*dev = filep->private_data;
+	struct list_head	*list = &dev->pending;
+	struct mISDNtimer	*timer, *next;
+
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
+
+	spin_lock_irq(&dev->lock);
+	while (!list_empty(list)) {
+		timer = list_first_entry(list, struct mISDNtimer, list);
+		spin_unlock_irq(&dev->lock);
+		del_timer_sync(&timer->tl);
+		spin_lock_irq(&dev->lock);
+		/* it might have been moved to ->expired */
+		list_del(&timer->list);
+		kfree(timer);
+	}
+	spin_unlock_irq(&dev->lock);
+
+	list_for_each_entry_safe(timer, next, &dev->expired, list) {
+		kfree(timer);
+	}
+	kfree(dev);
+	return 0;
+}
+
+static ssize_t
+mISDN_read(struct file *filep, char __user *buf, size_t count, loff_t *off)
+{
+	struct mISDNtimerdev	*dev = filep->private_data;
+	struct list_head *list = &dev->expired;
+	struct mISDNtimer	*timer;
+	int	ret = 0;
+
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s(%p, %p, %d, %p)\n", __func__,
+		       filep, buf, (int)count, off);
+
+	if (count < sizeof(int))
+		return -ENOSPC;
+
+	spin_lock_irq(&dev->lock);
+	while (list_empty(list) && (dev->work == 0)) {
+		spin_unlock_irq(&dev->lock);
+		if (filep->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+		wait_event_interruptible(dev->wait, (dev->work ||
+						     !list_empty(list)));
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+		spin_lock_irq(&dev->lock);
+	}
+	if (dev->work)
+		dev->work = 0;
+	if (!list_empty(list)) {
+		timer = list_first_entry(list, struct mISDNtimer, list);
+		list_del(&timer->list);
+		spin_unlock_irq(&dev->lock);
+		if (put_user(timer->id, (int __user *)buf))
+			ret = -EFAULT;
+		else
+			ret = sizeof(int);
+		kfree(timer);
+	} else {
+		spin_unlock_irq(&dev->lock);
+	}
+	return ret;
+}
+
+static __poll_t
+mISDN_poll(struct file *filep, poll_table *wait)
+{
+	struct mISDNtimerdev	*dev = filep->private_data;
+	__poll_t		mask = EPOLLERR;
+
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s(%p, %p)\n", __func__, filep, wait);
+	if (dev) {
+		poll_wait(filep, &dev->wait, wait);
+		mask = 0;
+		if (dev->work || !list_empty(&dev->expired))
+			mask |= (EPOLLIN | EPOLLRDNORM);
+		if (*debug & DEBUG_TIMER)
+			printk(KERN_DEBUG "%s work(%d) empty(%d)\n", __func__,
+			       dev->work, list_empty(&dev->expired));
+	}
+	return mask;
+}
+
+static void
+dev_expire_timer(struct timer_list *t)
+{
+	struct mISDNtimer *timer = from_timer(timer, t, tl);
+	u_long			flags;
+
+	spin_lock_irqsave(&timer->dev->lock, flags);
+	if (timer->id >= 0)
+		list_move_tail(&timer->list, &timer->dev->expired);
+	wake_up_interruptible(&timer->dev->wait);
+	spin_unlock_irqrestore(&timer->dev->lock, flags);
+}
+
+static int
+misdn_add_timer(struct mISDNtimerdev *dev, int timeout)
+{
+	int			id;
+	struct mISDNtimer	*timer;
+
+	if (!timeout) {
+		dev->work = 1;
+		wake_up_interruptible(&dev->wait);
+		id = 0;
+	} else {
+		timer = kzalloc(sizeof(struct mISDNtimer), GFP_KERNEL);
+		if (!timer)
+			return -ENOMEM;
+		timer->dev = dev;
+		timer_setup(&timer->tl, dev_expire_timer, 0);
+		spin_lock_irq(&dev->lock);
+		id = timer->id = dev->next_id++;
+		if (dev->next_id < 0)
+			dev->next_id = 1;
+		list_add_tail(&timer->list, &dev->pending);
+		timer->tl.expires = jiffies + ((HZ * (u_long)timeout) / 1000);
+		add_timer(&timer->tl);
+		spin_unlock_irq(&dev->lock);
+	}
+	return id;
+}
+
+static int
+misdn_del_timer(struct mISDNtimerdev *dev, int id)
+{
+	struct mISDNtimer	*timer;
+
+	spin_lock_irq(&dev->lock);
+	list_for_each_entry(timer, &dev->pending, list) {
+		if (timer->id == id) {
+			list_del_init(&timer->list);
+			timer->id = -1;
+			spin_unlock_irq(&dev->lock);
+			del_timer_sync(&timer->tl);
+			kfree(timer);
+			return id;
+		}
+	}
+	spin_unlock_irq(&dev->lock);
+	return 0;
+}
+
+static long
+mISDN_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
+{
+	struct mISDNtimerdev	*dev = filep->private_data;
+	int			id, tout, ret = 0;
+
+
+	if (*debug & DEBUG_TIMER)
+		printk(KERN_DEBUG "%s(%p, %x, %lx)\n", __func__,
+		       filep, cmd, arg);
+	mutex_lock(&mISDN_mutex);
+	switch (cmd) {
+	case IMADDTIMER:
+		if (get_user(tout, (int __user *)arg)) {
+			ret = -EFAULT;
+			break;
+		}
+		id = misdn_add_timer(dev, tout);
+		if (*debug & DEBUG_TIMER)
+			printk(KERN_DEBUG "%s add %d id %d\n", __func__,
+			       tout, id);
+		if (id < 0) {
+			ret = id;
+			break;
+		}
+		if (put_user(id, (int __user *)arg))
+			ret = -EFAULT;
+		break;
+	case IMDELTIMER:
+		if (get_user(id, (int __user *)arg)) {
+			ret = -EFAULT;
+			break;
+		}
+		if (*debug & DEBUG_TIMER)
+			printk(KERN_DEBUG "%s del id %d\n", __func__, id);
+		id = misdn_del_timer(dev, id);
+		if (put_user(id, (int __user *)arg))
+			ret = -EFAULT;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	mutex_unlock(&mISDN_mutex);
+	return ret;
+}
+
+static const struct file_operations mISDN_fops = {
+	.owner		= THIS_MODULE,
+	.read		= mISDN_read,
+	.poll		= mISDN_poll,
+	.unlocked_ioctl	= mISDN_ioctl,
+	.open		= mISDN_open,
+	.release	= mISDN_close,
+	.llseek		= no_llseek,
+};
+
+static struct miscdevice mISDNtimer = {
+	.minor	= MISC_DYNAMIC_MINOR,
+	.name	= "mISDNtimer",
+	.fops	= &mISDN_fops,
+};
+
+int
+mISDN_inittimer(u_int *deb)
+{
+	int	err;
+
+	debug = deb;
+	err = misc_register(&mISDNtimer);
+	if (err)
+		printk(KERN_WARNING "mISDN: Could not register timer device\n");
+	return err;
+}
+
+void mISDN_timer_cleanup(void)
+{
+	misc_deregister(&mISDNtimer);
+}