diff --git a/drivers/isdn/mISDN/Kconfig b/drivers/isdn/mISDN/Kconfig
index 231bd0d..6a97e86 100644
--- a/drivers/isdn/mISDN/Kconfig
+++ b/drivers/isdn/mISDN/Kconfig
@@ -7,3 +7,21 @@
 	help
 	  Enable support for the modular ISDN driver.
 
+if MISDN != n
+
+config MISDN_DSP
+	tristate "Digital Audio Processing of transparent data"
+	depends on MISDN
+	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 cancelation, 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 informations about this module and it's usage.
+	  If unsure, say 'N'.
+
+	source "drivers/isdn/hardware/mISDN/Kconfig"
+endif #MISDN
diff --git a/drivers/isdn/mISDN/Makefile b/drivers/isdn/mISDN/Makefile
index 87c563d..7f1a218 100644
--- a/drivers/isdn/mISDN/Makefile
+++ b/drivers/isdn/mISDN/Makefile
@@ -3,7 +3,9 @@
 #
 
 obj-$(CONFIG_MISDN) += mISDN_core.o
+obj-$(CONFIG_MISDN_DSP) += mISDN_dsp.o
 
 # multi objects
 
 mISDN_core-objs := core.o fsm.o socket.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
diff --git a/drivers/isdn/mISDN/dsp.h b/drivers/isdn/mISDN/dsp.h
new file mode 100644
index 0000000..6c3fed6
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp.h
@@ -0,0 +1,263 @@
+/*
+ * 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_DTMFCOEFF	0x8000 /* heavy output */
+
+/* options may be:
+ *
+ * bit 0 = use ulaw instead of alaw
+ * bit 1 = enable hfc hardware accelleration 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;
+extern u32 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_BUFLEN (4*128)
+
+struct dsp_dtmf {
+	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]; /* just the 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;
+};
+
+/*****************
+ * general stuff *
+ *****************/
+
+struct dsp {
+	struct list_head list;
+	struct mISDNchannel	ch;
+	struct mISDNchannel	*up;
+	unsigned char	name[64];
+	int		b_active;
+	int		echo; /* echo is enabled */
+	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		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(void *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(void *arg);
+
+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);
+
diff --git a/drivers/isdn/mISDN/dsp_audio.c b/drivers/isdn/mISDN/dsp_audio.c
new file mode 100644
index 0000000..1c2dd56
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_audio.c
@@ -0,0 +1,434 @@
+/*
+ * 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 "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 */
+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;
+}
+
+static int reverse_bits(int i)
+{
+	int z, j;
+	z = 0;
+
+	for (j = 0; j < 8; j++) {
+		if ((i & (1 << j)) != 0)
+			z |= 1 << (7 - j);
+	}
+	return z;
+}
+
+
+void dsp_audio_generate_law_tables(void)
+{
+	int i;
+	for (i = 0; i < 256; i++)
+		dsp_audio_alaw_to_s32[i] = alaw2linear(reverse_bits(i));
+
+	for (i = 0; i < 256; i++)
+		dsp_audio_ulaw_to_s32[i] = ulaw2linear(reverse_bits(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] =
+				reverse_bits(linear2ulaw(i));
+		}
+	} else {
+		/* generating alaw-table */
+		for (i = -32768; i < 32768; i++) {
+			dsp_audio_s16_to_law[i & 0xffff] =
+				reverse_bits(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 0000000..038191b
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_biquad.h
@@ -0,0 +1,65 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+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 0000000..18e411e
--- /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 0000000..e92b1ba
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_cmx.c
@@ -0,0 +1,1886 @@
+/*
+ * 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 diabled 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/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_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 echo=%d txmix=%d",
+		    odsp->name, odsp->echo, 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)%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 == 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 "kmalloc 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_meber 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 "kmalloc 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;
+
+	/* 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) {
+			/* 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: already echo */
+		if (dsp->pcm_slot_tx >= 0 && dsp->pcm_slot_rx < 0 &&
+		    dsp->pcm_bank_tx == 2 && dsp->pcm_bank_rx == 2)
+			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);
+			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_tx] = 0;
+				if (finddsp->pcm_slot_tx >= 0 &&
+				    finddsp->pcm_slot_tx < sizeof(freeslots))
+					freeslots[finddsp->pcm_slot_rx] = 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 */
+			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);
+		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 whithout 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) {
+			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 cannot form a conf, because "
+				    "tx_data is turned on\n",
+				    __func__, member->dsp->name);
+			goto conf_software;
+		}
+		/* 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 = 0;
+				conf->software = 1;
+				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_tx] = 0;
+					if (dsp->pcm_slot_tx >= 0 &&
+					    dsp->pcm_slot_tx <
+					    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) {
+				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 = 0;
+			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 = 0;
+				conf->software = 1;
+				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_tx] = 0;
+					if (dsp->pcm_slot_tx >= 0 &&
+					    dsp->pcm_slot_tx <
+					    sizeof(freeslots))
+						freeslots[dsp->pcm_slot_rx] = 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 = 0;
+			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.. */
+
+	/* in case of hdlc, we change to software */
+	if (dsp->hdlc)
+		goto conf_software;
+
+	/* if all members already have the same conference */
+	if (all_conf)
+		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) {
+			/* 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);
+		}
+		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;
+}
+
+
+/*
+ * 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);
+			dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
+				& CMX_BUFF_MASK;
+		} else {
+			dsp->rx_R = 0;
+			dsp->rx_W = dsp->cmx_delay;
+		}
+	}
+	/* 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_CMX)
+			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 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));
+	}
+	/* 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_CMX)
+				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);
+}
+
+
+/*
+ * 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;
+
+	/* don't process if: */
+	if (!dsp->b_active) { /* if not active */
+		dsp->last_tx = 0;
+		return;
+	}
+	if (dsp->pcm_slot_tx >= 0 && /* connected to pcm slot */
+	    dsp->tx_R == dsp->tx_W && /* AND no tx-data */
+	    !(dsp->tone.tone && dsp->tone.software)) { /* AND not soft tones */
+		dsp->last_tx = 0;
+		return;
+	}
+
+#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) {
+			/* -> 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)
+				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) {
+			/*
+			 * -> 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;
+	}
+#ifdef DSP_NEVER_DEFINED
+	}
+#endif
+	/* PROCESS DATA (three or more members) */
+	/* -> if echo is NOT enabled */
+	if (!dsp->echo) {
+		/*
+		 * -> substract 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,
+	 * becuase we want what we send, not what we filtered
+	 */
+	if (dsp->tx_data) {
+		/* PREPARE RESULT */
+		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;
+			memcpy(skb_put(txskb, len), nskb->data+preload, len);
+			/* queue (trigger later) */
+			skb_queue_tail(&dsp->sendq, txskb);
+		}
+	}
+	/* 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);
+}
+
+u32	samplecount;
+struct timer_list dsp_spl_tl;
+u32	dsp_spl_jiffies; /* calculate the next time to fire */
+u32	dsp_start_jiffies; /* jiffies at the time, the calculation begins */
+struct timeval dsp_start_tv; /* time at start of calculation */
+
+void
+dsp_cmx_send(void *arg)
+{
+	struct dsp_conf *conf;
+	struct dsp_conf_member *member;
+	struct dsp *dsp;
+	int mustmix, members;
+	s32 mixbuffer[MAX_POLL+100], *c;
+	u8 *p, *q;
+	int r, rr;
+	int jittercheck = 0, delay, i;
+	u_long flags;
+	struct timeval tv;
+	u32 elapsed;
+	s16 length;
+
+	/* lock */
+	spin_lock_irqsave(&dsp_lock, flags);
+
+	if (!dsp_start_tv.tv_sec) {
+		do_gettimeofday(&dsp_start_tv);
+		length = dsp_poll;
+	} else {
+		do_gettimeofday(&tv);
+		elapsed = ((tv.tv_sec - dsp_start_tv.tv_sec) * 8000)
+		    + ((s32)(tv.tv_usec / 125) - (dsp_start_tv.tv_usec / 125));
+		dsp_start_tv.tv_sec = tv.tv_sec;
+		dsp_start_tv.tv_usec = tv.tv_usec;
+		length = elapsed;
+	}
+	if (length > MAX_POLL + 100)
+		length = MAX_POLL + 100;
+/* printk(KERN_DEBUG "len=%d dsp_count=0x%x.%04x dsp_poll_diff=0x%x.%04x\n",
+ length, dsp_count >> 16, dsp_count & 0xffff, dsp_poll_diff >> 16,
+ dsp_poll_diff & 0xffff);
+ */
+
+	/*
+	 * check if jitter needs to be checked
+	 * (this is about every second = 8192 samples)
+	 */
+	samplecount += length;
+	if ((samplecount & 8191) < length)
+		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
+			 */
+			if (delay && !dsp->cmx_delay) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					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) & 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->tx_dejitter) {
+				if (dsp_debug & DEBUG_DSP_CMX)
+					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) & 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;
+	if (space <= 0)
+		space += CMX_BUFF_SIZE;
+	/* write-pointer should not overrun nor reach read pointer */
+	if (space-1 < skb->len)
+		/* write to the space we have left */
+		ww = (ww - 1) & CMX_BUFF_MASK;
+	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 hardware (echo) */
+		if (dsp->pcm_slot_tx >= 0)
+			return;
+		if (dsp->echo)
+			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 || 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 0000000..2f10ed8
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_core.c
@@ -0,0 +1,1191 @@
+/*
+ * 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
+ *		For changes and modifications please read
+ *		../../../Documentation/isdn/mISDN.cert
+ *
+ * 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 performane 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 swithed on/off individually without loosing
+ * 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 usefull if only announcements are played. Not sending is
+ * usefull if an answering machine records audio. Not sending and receiving is
+ * usefull 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/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include "core.h"
+#include "dsp.h"
+
+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;*/
+
+spinlock_t dsp_lock; /* global dsp lock */
+struct list_head dsp_ilist;
+struct 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;
+
+	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 && dsp->pcm_slot_tx < 0)
+		rx_off = 0;
+	/* bridge in software */
+	else if (dsp->conf) {
+		if (dsp->conf->software)
+			rx_off = 0;
+	}
+
+	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);
+	}
+}
+
+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__);
+	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)) {
+			printk(KERN_NOTICE "changing DTMF Threshold "
+				"to %d\n", *((int *)data));
+			dsp->dtmf.treshold = (*(int *)data) * 10000;
+		}
+		/* init goertzel */
+		dsp_dtmf_goertzel_init(dsp);
+
+		/* check dtmf hardware */
+		dsp_dtmf_hardware(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.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 = 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 = 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 mebers\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 mebers\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;
+			/* miliseconds 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 ? (char *)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 (dsp_options & DSP_OPT_NOHARDWARE)
+		return;
+	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_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;
+	int			cont;
+	struct			sk_buff *nskb;
+	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;
+		}
+
+		/* 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);
+		/* 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);
+			while (*digits) {
+				if (dsp_debug & DEBUG_DSP_DTMF)
+					printk(KERN_DEBUG "%s: digit"
+					    "(%c) to layer %s\n",
+					    __func__, *digits, dsp->name);
+				cont = DTMF_TONE_VAL | *digits;
+				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);
+				}
+				digits++;
+			}
+		}
+		/* we need to process receive data if software */
+		spin_lock_irqsave(&dsp_lock, flags);
+		if (dsp->pcm_slot_tx < 0 && dsp->pcm_slot_rx < 0) {
+			/* process data from card at cmx */
+			dsp_cmx_receive(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;
+	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 */
+			spin_lock_irqsave(&dsp_lock, flags);
+			if (dsp->b_active) {
+				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);
+		/* 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;
+	int		err = 0;
+
+	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 err;
+}
+
+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 = vmalloc(sizeof(struct dsp));
+	if (!ndsp) {
+		printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
+		return -ENOMEM;
+	}
+	memset(ndsp, 0, sizeof(struct dsp));
+	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 */
+	ndsp->tone.tl.function = (void *)dsp_tone_timeout;
+	ndsp->tone.tl.data = (long) ndsp;
+	init_timer(&ndsp->tone.tl);
+
+	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 dsp_init(void)
+{
+	int err;
+	int tics;
+
+	printk(KERN_INFO "DSP modul %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);
+
+	spin_lock_init(&dsp_lock);
+	INIT_LIST_HEAD(&dsp_ilist);
+	INIT_LIST_HEAD(&conf_ilist);
+
+	/* 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 */
+	dsp_spl_tl.function = (void *)dsp_cmx_send;
+	dsp_spl_tl.data = 0;
+	init_timer(&dsp_spl_tl);
+	dsp_spl_tl.expires = jiffies + dsp_tics;
+	dsp_spl_jiffies = dsp_spl_tl.expires;
+	add_timer(&dsp_spl_tl);
+
+	return 0;
+}
+
+
+static void dsp_cleanup(void)
+{
+	mISDN_unregister_Bprotocol(&DSP);
+
+	if (timer_pending(&dsp_spl_tl))
+		del_timer(&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 0000000..efc371c
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_dtmf.c
@@ -0,0 +1,303 @@
+/*
+ * 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->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 speach, 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)
+		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 inbetween */
+		}
+		/* 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 0000000..8a20af4
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_ecdis.h
@@ -0,0 +1,110 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#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 0000000..eb892d9
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_hwec.c
@@ -0,0 +1,138 @@
+/*
+ * dsp_hwec.c:
+ * builtin mISDN dsp pipeline element for enabling the hw echocanceller
+ *
+ * Copyright (C) 2007, Nadi Sarrar
+ *
+ * Nadi Sarrar <nadi@beronet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ */
+
+#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 = sizeof(args) / sizeof(struct mISDN_dsp_element_arg),
+	.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[len + 1];
+		char *dup, *tok, *name, *val;
+		int tmp;
+
+		strcpy(_dup, arg);
+		dup = _dup;
+
+		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;
+			}
+		}
+	}
+
+_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 0000000..eebe80c
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_hwec.h
@@ -0,0 +1,10 @@
+/*
+ * 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 0000000..850260a
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_pipeline.c
@@ -0,0 +1,348 @@
+/*
+ * dsp_pipeline.c: pipelined audio processing
+ *
+ * Copyright (C) 2007, Nadi Sarrar
+ *
+ * Nadi Sarrar <nadi@beronet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/string.h>
+#include <linux/mISDNif.h>
+#include <linux/mISDNdsp.h>
+#include "dsp.h"
+#include "dsp_hwec.h"
+
+/* uncomment for debugging */
+/*#define PIPELINE_DEBUG*/
+
+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);
+	ssize_t len = 0;
+	int i = 0;
+
+	*buf = 0;
+	for (; i < elem->num_args; ++i)
+		len = sprintf(buf, "%sName:        %s\n%s%s%sDescription: %s\n"
+			"\n", buf,
+			  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 len;
+}
+
+static struct device_attribute element_attributes[] = {
+	__ATTR(args, 0444, attr_show_args, NULL),
+};
+
+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_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->elem = elem;
+
+	entry->dev.class = elements_class;
+	dev_set_drvdata(&entry->dev, elem);
+	snprintf(entry->dev.bus_id, BUS_ID_SIZE, elem->name);
+	ret = device_register(&entry->dev);
+	if (ret) {
+		printk(KERN_ERR "%s: failed to register %s\n",
+			__func__, elem->name);
+		goto err1;
+	}
+
+	for (i = 0; i < (sizeof(element_attributes)
+		/ sizeof(struct device_attribute)); ++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;
+		}
+
+	list_add_tail(&entry->list, &dsp_elements);
+
+	printk(KERN_DEBUG "%s: %s registered\n", __func__, elem->name);
+
+	return 0;
+
+err2:
+	device_unregister(&entry->dev);
+err1:
+	kfree(entry);
+	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) {
+			list_del(&entry->list);
+			device_unregister(&entry->dev);
+			kfree(entry);
+			printk(KERN_DEBUG "%s: %s unregistered\n",
+				__func__, elem->name);
+			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);
+
+#ifdef PIPELINE_DEBUG
+	printk(KERN_DEBUG "%s: dsp pipeline module initialized\n", __func__);
+#endif
+
+	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);
+	}
+
+	printk(KERN_DEBUG "%s: dsp pipeline module exited\n", __func__);
+}
+
+int dsp_pipeline_init(struct dsp_pipeline *pipeline)
+{
+	if (!pipeline)
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&pipeline->list);
+
+#ifdef PIPELINE_DEBUG
+	printk(KERN_DEBUG "%s: dsp pipeline ready\n", __func__);
+#endif
+
+	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);
+
+#ifdef PIPELINE_DEBUG
+	printk(KERN_DEBUG "%s: dsp pipeline destroyed\n", __func__);
+#endif
+}
+
+int dsp_pipeline_build(struct dsp_pipeline *pipeline, const char *cfg)
+{
+	int len, incomplete = 0, found = 0;
+	char *dup, *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);
+
+	if (!cfg)
+		return 0;
+
+	len = strlen(cfg);
+	if (!len)
+		return 0;
+
+	dup = kmalloc(len + 1, GFP_KERNEL);
+	if (!dup)
+		return 0;
+	strcpy(dup, cfg);
+	while ((tok = strsep(&dup, "|"))) {
+		if (!strlen(tok))
+			continue;
+		name = strsep(&tok, "(");
+		args = strsep(&tok, ")");
+		if (args && !*args)
+			args = 0;
+
+		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_KERNEL);
+				if (!pipeline_entry) {
+					printk(KERN_DEBUG "%s: failed to add "
+					    "entry to pipeline: %s (out of "
+					    "memory)\n", __func__, elem->name);
+					incomplete = 1;
+					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);
+#ifdef PIPELINE_DEBUG
+						printk(KERN_DEBUG "%s: created "
+						    "instance of %s%s%s\n",
+						    __func__, name, args ?
+						    " with args " : "", args ?
+						    args : "");
+#endif
+					} else {
+						printk(KERN_DEBUG "%s: failed "
+						  "to add entry to pipeline: "
+						  "%s (new() returned NULL)\n",
+						  __func__, elem->name);
+						kfree(pipeline_entry);
+						incomplete = 1;
+					}
+				}
+				found = 1;
+				break;
+			}
+
+		if (found)
+			found = 0;
+		else {
+			printk(KERN_DEBUG "%s: element not found, skipping: "
+				"%s\n", __func__, name);
+			incomplete = 1;
+		}
+	}
+
+_out:
+	if (!list_empty(&pipeline->list))
+		pipeline->inuse = 1;
+	else
+		pipeline->inuse = 0;
+
+#ifdef PIPELINE_DEBUG
+	printk(KERN_DEBUG "%s: dsp pipeline built%s: %s\n",
+		__func__, incomplete ? " incomplete" : "", cfg);
+#endif
+	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)
+{
+	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);
+}
+
+
diff --git a/drivers/isdn/mISDN/dsp_tones.c b/drivers/isdn/mISDN/dsp_tones.c
new file mode 100644
index 0000000..23dd0dd
--- /dev/null
+++ b/drivers/isdn/mISDN/dsp_tones.c
@@ -0,0 +1,551 @@
+/*
+ * 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/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 *
+ ****************************/
+
+struct pattern {
+	int tone;
+	u8 *data[10];
+	u32 *siz[10];
+	u32 seq[10];
+} pattern[] = {
+	{TONE_GERMAN_DIALTONE,
+	{DATA_GA, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{1900, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDDIALTONE,
+	{DATA_GO, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{1998, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_DIALTONE,
+	{DATA_DT, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_DT, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{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, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, 0, 0, 0, 0},
+	{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, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, 0, 0, 0, 0},
+	{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, 0, 0, 0, 0},
+	{SIZE_DT, SIZE_S, SIZE_DT, SIZE_S, SIZE_DT, SIZE_S, 0, 0, 0, 0},
+	{2000, 2000, 2000, 2000, 2000, 12000, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_RINGING,
+	{DATA_GA, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{8000, 32000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDRINGING,
+	{DATA_GO, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{8000, 40000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_RINGING,
+	{DATA_RI, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_RI, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{8000, 32000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_RINGPBX,
+	{DATA_GA, DATA_S, DATA_GA, DATA_S, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, SIZE_GA, SIZE_S, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDRINGPBX,
+	{DATA_GO, DATA_S, DATA_GO, DATA_S, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_RINGPBX,
+	{DATA_RI, DATA_S, DATA_RI, DATA_S, 0, 0, 0, 0, 0, 0},
+	{SIZE_RI, SIZE_S, SIZE_RI, SIZE_S, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 4000, 28000, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_BUSY,
+	{DATA_GA, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDBUSY,
+	{DATA_GO, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{1000, 5000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_BUSY,
+	{DATA_BU, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_BU, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_HANGUP,
+	{DATA_GA, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{4000, 4000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_OLDHANGUP,
+	{DATA_GO, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{1000, 5000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_AMERICAN_HANGUP,
+	{DATA_DT, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_DT, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{8000, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_SPECIAL_INFO,
+	{DATA_S1, DATA_S2, DATA_S3, DATA_S, 0, 0, 0, 0, 0, 0},
+	{SIZE_S1, SIZE_S2, SIZE_S3, SIZE_S, 0, 0, 0, 0, 0, 0},
+	{2666, 2666, 2666, 8002, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_GASSENBESETZT,
+	{DATA_GA, DATA_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{SIZE_GA, SIZE_S, 0, 0, 0, 0, 0, 0, 0, 0},
+	{2000, 2000, 0, 0, 0, 0, 0, 0, 0, 0} },
+
+	{TONE_GERMAN_AUFSCHALTTON,
+	{DATA_GO, DATA_S, DATA_GO, DATA_S, 0, 0, 0, 0, 0, 0},
+	{SIZE_GO, SIZE_S, SIZE_GO, SIZE_S, 0, 0, 0, 0, 0, 0},
+	{1000, 5000, 1000, 17000, 0, 0, 0, 0, 0, 0} },
+
+	{0,
+	{0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	{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) {
+			/* warp arround */
+			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(void *arg)
+{
+	struct dsp *dsp = arg;
+	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, 0, 0);
+	else
+		dsp_tone_hw_message(dsp, pat->data[index], *(pat->siz[index]));
+	/* set timer */
+	init_timer(&tone->tl);
+	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)
+		if (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);
+		init_timer(&tonet->tl);
+		tonet->tl.expires = jiffies + (pat->seq[0] * HZ) / 8000;
+		add_timer(&tonet->tl);
+	} else {
+		tonet->software = 1;
+	}
+
+	return 0;
+}
+
+
+
+
+