1/*
2 * Author       Andreas Eversberg (jolly@eversberg.eu)
3 * Based on source code structure by
4 *		Karsten Keil (keil@isdn4linux.de)
5 *
6 *		This file is (c) under GNU PUBLIC LICENSE
7 *		For changes and modifications please read
8 *		../../../Documentation/isdn/mISDN.cert
9 *
10 * Thanks to    Karsten Keil (great drivers)
11 *              Cologne Chip (great chips)
12 *
13 * This module does:
14 *		Real-time tone generation
15 *		DTMF detection
16 *		Real-time cross-connection and conferrence
17 *		Compensate jitter due to system load and hardware fault.
18 *		All features are done in kernel space and will be realized
19 *		using hardware, if available and supported by chip set.
20 *		Blowfish encryption/decryption
21 */
22
23/* STRUCTURE:
24 *
25 * The dsp module provides layer 2 for b-channels (64kbit). It provides
26 * transparent audio forwarding with special digital signal processing:
27 *
28 * - (1) generation of tones
29 * - (2) detection of dtmf tones
30 * - (3) crossconnecting and conferences (clocking)
31 * - (4) echo generation for delay test
32 * - (5) volume control
33 * - (6) disable receive data
34 * - (7) pipeline
35 * - (8) encryption/decryption
36 *
37 * Look:
38 *             TX            RX
39 *         ------upper layer------
40 *             |             ^
41 *             |             |(6)
42 *             v             |
43 *       +-----+-------------+-----+
44 *       |(3)(4)                   |
45 *       |           CMX           |
46 *       |                         |
47 *       |           +-------------+
48 *       |           |       ^
49 *       |           |       |
50 *       |+---------+|  +----+----+
51 *       ||(1)      ||  |(2)      |
52 *       ||         ||  |         |
53 *       ||  Tones  ||  |  DTMF   |
54 *       ||         ||  |         |
55 *       ||         ||  |         |
56 *       |+----+----+|  +----+----+
57 *       +-----+-----+       ^
58 *             |             |
59 *             v             |
60 *        +----+----+   +----+----+
61 *        |(5)      |   |(5)      |
62 *        |         |   |         |
63 *        |TX Volume|   |RX Volume|
64 *        |         |   |         |
65 *        |         |   |         |
66 *        +----+----+   +----+----+
67 *             |             ^
68 *             |             |
69 *             v             |
70 *        +----+-------------+----+
71 *        |(7)                    |
72 *        |                       |
73 *        |  Pipeline Processing  |
74 *        |                       |
75 *        |                       |
76 *        +----+-------------+----+
77 *             |             ^
78 *             |             |
79 *             v             |
80 *        +----+----+   +----+----+
81 *        |(8)      |   |(8)      |
82 *        |         |   |         |
83 *        | Encrypt |   | Decrypt |
84 *        |         |   |         |
85 *        |         |   |         |
86 *        +----+----+   +----+----+
87 *             |             ^
88 *             |             |
89 *             v             |
90 *         ------card  layer------
91 *             TX            RX
92 *
93 * Above you can see the logical data flow. If software is used to do the
94 * process, it is actually the real data flow. If hardware is used, data
95 * may not flow, but hardware commands to the card, to provide the data flow
96 * as shown.
97 *
98 * NOTE: The channel must be activated in order to make dsp work, even if
99 * no data flow to the upper layer is intended. Activation can be done
100 * after and before controlling the setting using PH_CONTROL requests.
101 *
102 * DTMF: Will be detected by hardware if possible. It is done before CMX
103 * processing.
104 *
105 * Tones: Will be generated via software if endless looped audio fifos are
106 * not supported by hardware. Tones will override all data from CMX.
107 * It is not required to join a conference to use tones at any time.
108 *
109 * CMX: Is transparent when not used. When it is used, it will do
110 * crossconnections and conferences via software if not possible through
111 * hardware. If hardware capability is available, hardware is used.
112 *
113 * Echo: Is generated by CMX and is used to check performance of hard and
114 * software CMX.
115 *
116 * The CMX has special functions for conferences with one, two and more
117 * members. It will allow different types of data flow. Receive and transmit
118 * data to/form upper layer may be swithed on/off individually without losing
119 * features of CMX, Tones and DTMF.
120 *
121 * Echo Cancellation: Sometimes we like to cancel echo from the interface.
122 * Note that a VoIP call may not have echo caused by the IP phone. The echo
123 * is generated by the telephone line connected to it. Because the delay
124 * is high, it becomes an echo. RESULT: Echo Cachelation is required if
125 * both echo AND delay is applied to an interface.
126 * Remember that software CMX always generates a more or less delay.
127 *
128 * If all used features can be realized in hardware, and if transmit and/or
129 * receive data ist disabled, the card may not send/receive any data at all.
130 * Not receiving is useful if only announcements are played. Not sending is
131 * useful if an answering machine records audio. Not sending and receiving is
132 * useful during most states of the call. If supported by hardware, tones
133 * will be played without cpu load. Small PBXs and NT-Mode applications will
134 * not need expensive hardware when processing calls.
135 *
136 *
137 * LOCKING:
138 *
139 * When data is received from upper or lower layer (card), the complete dsp
140 * module is locked by a global lock.  This lock MUST lock irq, because it
141 * must lock timer events by DSP poll timer.
142 * When data is ready to be transmitted down, the data is queued and sent
143 * outside lock and timer event.
144 * PH_CONTROL must not change any settings, join or split conference members
145 * during process of data.
146 *
147 * HDLC:
148 *
149 * It works quite the same as transparent, except that HDLC data is forwarded
150 * to all other conference members if no hardware bridging is possible.
151 * Send data will be writte to sendq. Sendq will be sent if confirm is received.
152 * Conference cannot join, if one member is not hdlc.
153 *
154 */
155
156#include <linux/delay.h>
157#include <linux/gfp.h>
158#include <linux/mISDNif.h>
159#include <linux/mISDNdsp.h>
160#include <linux/module.h>
161#include <linux/vmalloc.h>
162#include "core.h"
163#include "dsp.h"
164
165static const char *mISDN_dsp_revision = "2.0";
166
167static int debug;
168static int options;
169static int poll;
170static int dtmfthreshold = 100;
171
172MODULE_AUTHOR("Andreas Eversberg");
173module_param(debug, uint, S_IRUGO | S_IWUSR);
174module_param(options, uint, S_IRUGO | S_IWUSR);
175module_param(poll, uint, S_IRUGO | S_IWUSR);
176module_param(dtmfthreshold, uint, S_IRUGO | S_IWUSR);
177MODULE_LICENSE("GPL");
178
179/*int spinnest = 0;*/
180
181spinlock_t dsp_lock; /* global dsp lock */
182struct list_head dsp_ilist;
183struct list_head conf_ilist;
184int dsp_debug;
185int dsp_options;
186int dsp_poll, dsp_tics;
187
188/* check if rx may be turned off or must be turned on */
189static void
190dsp_rx_off_member(struct dsp *dsp)
191{
192	struct mISDN_ctrl_req	cq;
193	int rx_off = 1;
194
195	memset(&cq, 0, sizeof(cq));
196
197	if (!dsp->features_rx_off)
198		return;
199
200	/* not disabled */
201	if (!dsp->rx_disabled)
202		rx_off = 0;
203	/* software dtmf */
204	else if (dsp->dtmf.software)
205		rx_off = 0;
206	/* echo in software */
207	else if (dsp->echo.software)
208		rx_off = 0;
209	/* bridge in software */
210	else if (dsp->conf && dsp->conf->software)
211		rx_off = 0;
212	/* data is not required by user space and not required
213	 * for echo dtmf detection, soft-echo, soft-bridging */
214
215	if (rx_off == dsp->rx_is_off)
216		return;
217
218	if (!dsp->ch.peer) {
219		if (dsp_debug & DEBUG_DSP_CORE)
220			printk(KERN_DEBUG "%s: no peer, no rx_off\n",
221			       __func__);
222		return;
223	}
224	cq.op = MISDN_CTRL_RX_OFF;
225	cq.p1 = rx_off;
226	if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
227		printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
228		       __func__);
229		return;
230	}
231	dsp->rx_is_off = rx_off;
232	if (dsp_debug & DEBUG_DSP_CORE)
233		printk(KERN_DEBUG "%s: %s set rx_off = %d\n",
234		       __func__, dsp->name, rx_off);
235}
236static void
237dsp_rx_off(struct dsp *dsp)
238{
239	struct dsp_conf_member	*member;
240
241	if (dsp_options & DSP_OPT_NOHARDWARE)
242		return;
243
244	/* no conf */
245	if (!dsp->conf) {
246		dsp_rx_off_member(dsp);
247		return;
248	}
249	/* check all members in conf */
250	list_for_each_entry(member, &dsp->conf->mlist, list) {
251		dsp_rx_off_member(member->dsp);
252	}
253}
254
255/* enable "fill empty" feature */
256static void
257dsp_fill_empty(struct dsp *dsp)
258{
259	struct mISDN_ctrl_req	cq;
260
261	memset(&cq, 0, sizeof(cq));
262
263	if (!dsp->ch.peer) {
264		if (dsp_debug & DEBUG_DSP_CORE)
265			printk(KERN_DEBUG "%s: no peer, no fill_empty\n",
266			       __func__);
267		return;
268	}
269	cq.op = MISDN_CTRL_FILL_EMPTY;
270	cq.p1 = 1;
271	if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
272		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
273		       __func__);
274		return;
275	}
276	if (dsp_debug & DEBUG_DSP_CORE)
277		printk(KERN_DEBUG "%s: %s set fill_empty = 1\n",
278		       __func__, dsp->name);
279}
280
281static int
282dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
283{
284	struct sk_buff	*nskb;
285	int ret = 0;
286	int cont;
287	u8 *data;
288	int len;
289
290	if (skb->len < sizeof(int))
291		printk(KERN_ERR "%s: PH_CONTROL message too short\n", __func__);
292	cont = *((int *)skb->data);
293	len = skb->len - sizeof(int);
294	data = skb->data + sizeof(int);
295
296	switch (cont) {
297	case DTMF_TONE_START: /* turn on DTMF */
298		if (dsp->hdlc) {
299			ret = -EINVAL;
300			break;
301		}
302		if (dsp_debug & DEBUG_DSP_CORE)
303			printk(KERN_DEBUG "%s: start dtmf\n", __func__);
304		if (len == sizeof(int)) {
305			if (dsp_debug & DEBUG_DSP_CORE)
306				printk(KERN_NOTICE "changing DTMF Threshold "
307				       "to %d\n", *((int *)data));
308			dsp->dtmf.treshold = (*(int *)data) * 10000;
309		}
310		dsp->dtmf.enable = 1;
311		/* init goertzel */
312		dsp_dtmf_goertzel_init(dsp);
313
314		/* check dtmf hardware */
315		dsp_dtmf_hardware(dsp);
316		dsp_rx_off(dsp);
317		break;
318	case DTMF_TONE_STOP: /* turn off DTMF */
319		if (dsp_debug & DEBUG_DSP_CORE)
320			printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
321		dsp->dtmf.enable = 0;
322		dsp->dtmf.hardware = 0;
323		dsp->dtmf.software = 0;
324		break;
325	case DSP_CONF_JOIN: /* join / update conference */
326		if (len < sizeof(int)) {
327			ret = -EINVAL;
328			break;
329		}
330		if (*((u32 *)data) == 0)
331			goto conf_split;
332		if (dsp_debug & DEBUG_DSP_CORE)
333			printk(KERN_DEBUG "%s: join conference %d\n",
334			       __func__, *((u32 *)data));
335		ret = dsp_cmx_conf(dsp, *((u32 *)data));
336		/* dsp_cmx_hardware will also be called here */
337		dsp_rx_off(dsp);
338		if (dsp_debug & DEBUG_DSP_CMX)
339			dsp_cmx_debug(dsp);
340		break;
341	case DSP_CONF_SPLIT: /* remove from conference */
342	conf_split:
343		if (dsp_debug & DEBUG_DSP_CORE)
344			printk(KERN_DEBUG "%s: release conference\n", __func__);
345		ret = dsp_cmx_conf(dsp, 0);
346		/* dsp_cmx_hardware will also be called here */
347		if (dsp_debug & DEBUG_DSP_CMX)
348			dsp_cmx_debug(dsp);
349		dsp_rx_off(dsp);
350		break;
351	case DSP_TONE_PATT_ON: /* play tone */
352		if (dsp->hdlc) {
353			ret = -EINVAL;
354			break;
355		}
356		if (len < sizeof(int)) {
357			ret = -EINVAL;
358			break;
359		}
360		if (dsp_debug & DEBUG_DSP_CORE)
361			printk(KERN_DEBUG "%s: turn tone 0x%x on\n",
362			       __func__, *((int *)skb->data));
363		ret = dsp_tone(dsp, *((int *)data));
364		if (!ret) {
365			dsp_cmx_hardware(dsp->conf, dsp);
366			dsp_rx_off(dsp);
367		}
368		if (!dsp->tone.tone)
369			goto tone_off;
370		break;
371	case DSP_TONE_PATT_OFF: /* stop tone */
372		if (dsp->hdlc) {
373			ret = -EINVAL;
374			break;
375		}
376		if (dsp_debug & DEBUG_DSP_CORE)
377			printk(KERN_DEBUG "%s: turn tone off\n", __func__);
378		dsp_tone(dsp, 0);
379		dsp_cmx_hardware(dsp->conf, dsp);
380		dsp_rx_off(dsp);
381		/* reset tx buffers (user space data) */
382	tone_off:
383		dsp->rx_W = 0;
384		dsp->rx_R = 0;
385		break;
386	case DSP_VOL_CHANGE_TX: /* change volume */
387		if (dsp->hdlc) {
388			ret = -EINVAL;
389			break;
390		}
391		if (len < sizeof(int)) {
392			ret = -EINVAL;
393			break;
394		}
395		dsp->tx_volume = *((int *)data);
396		if (dsp_debug & DEBUG_DSP_CORE)
397			printk(KERN_DEBUG "%s: change tx vol to %d\n",
398			       __func__, dsp->tx_volume);
399		dsp_cmx_hardware(dsp->conf, dsp);
400		dsp_dtmf_hardware(dsp);
401		dsp_rx_off(dsp);
402		break;
403	case DSP_VOL_CHANGE_RX: /* change volume */
404		if (dsp->hdlc) {
405			ret = -EINVAL;
406			break;
407		}
408		if (len < sizeof(int)) {
409			ret = -EINVAL;
410			break;
411		}
412		dsp->rx_volume = *((int *)data);
413		if (dsp_debug & DEBUG_DSP_CORE)
414			printk(KERN_DEBUG "%s: change rx vol to %d\n",
415			       __func__, dsp->tx_volume);
416		dsp_cmx_hardware(dsp->conf, dsp);
417		dsp_dtmf_hardware(dsp);
418		dsp_rx_off(dsp);
419		break;
420	case DSP_ECHO_ON: /* enable echo */
421		dsp->echo.software = 1; /* soft echo */
422		if (dsp_debug & DEBUG_DSP_CORE)
423			printk(KERN_DEBUG "%s: enable cmx-echo\n", __func__);
424		dsp_cmx_hardware(dsp->conf, dsp);
425		dsp_rx_off(dsp);
426		if (dsp_debug & DEBUG_DSP_CMX)
427			dsp_cmx_debug(dsp);
428		break;
429	case DSP_ECHO_OFF: /* disable echo */
430		dsp->echo.software = 0;
431		dsp->echo.hardware = 0;
432		if (dsp_debug & DEBUG_DSP_CORE)
433			printk(KERN_DEBUG "%s: disable cmx-echo\n", __func__);
434		dsp_cmx_hardware(dsp->conf, dsp);
435		dsp_rx_off(dsp);
436		if (dsp_debug & DEBUG_DSP_CMX)
437			dsp_cmx_debug(dsp);
438		break;
439	case DSP_RECEIVE_ON: /* enable receive to user space */
440		if (dsp_debug & DEBUG_DSP_CORE)
441			printk(KERN_DEBUG "%s: enable receive to user "
442			       "space\n", __func__);
443		dsp->rx_disabled = 0;
444		dsp_rx_off(dsp);
445		break;
446	case DSP_RECEIVE_OFF: /* disable receive to user space */
447		if (dsp_debug & DEBUG_DSP_CORE)
448			printk(KERN_DEBUG "%s: disable receive to "
449			       "user space\n", __func__);
450		dsp->rx_disabled = 1;
451		dsp_rx_off(dsp);
452		break;
453	case DSP_MIX_ON: /* enable mixing of tx data */
454		if (dsp->hdlc) {
455			ret = -EINVAL;
456			break;
457		}
458		if (dsp_debug & DEBUG_DSP_CORE)
459			printk(KERN_DEBUG "%s: enable mixing of "
460			       "tx-data with conf mebers\n", __func__);
461		dsp->tx_mix = 1;
462		dsp_cmx_hardware(dsp->conf, dsp);
463		dsp_rx_off(dsp);
464		if (dsp_debug & DEBUG_DSP_CMX)
465			dsp_cmx_debug(dsp);
466		break;
467	case DSP_MIX_OFF: /* disable mixing of tx data */
468		if (dsp->hdlc) {
469			ret = -EINVAL;
470			break;
471		}
472		if (dsp_debug & DEBUG_DSP_CORE)
473			printk(KERN_DEBUG "%s: disable mixing of "
474			       "tx-data with conf mebers\n", __func__);
475		dsp->tx_mix = 0;
476		dsp_cmx_hardware(dsp->conf, dsp);
477		dsp_rx_off(dsp);
478		if (dsp_debug & DEBUG_DSP_CMX)
479			dsp_cmx_debug(dsp);
480		break;
481	case DSP_TXDATA_ON: /* enable txdata */
482		dsp->tx_data = 1;
483		if (dsp_debug & DEBUG_DSP_CORE)
484			printk(KERN_DEBUG "%s: enable tx-data\n", __func__);
485		dsp_cmx_hardware(dsp->conf, dsp);
486		dsp_rx_off(dsp);
487		if (dsp_debug & DEBUG_DSP_CMX)
488			dsp_cmx_debug(dsp);
489		break;
490	case DSP_TXDATA_OFF: /* disable txdata */
491		dsp->tx_data = 0;
492		if (dsp_debug & DEBUG_DSP_CORE)
493			printk(KERN_DEBUG "%s: disable tx-data\n", __func__);
494		dsp_cmx_hardware(dsp->conf, dsp);
495		dsp_rx_off(dsp);
496		if (dsp_debug & DEBUG_DSP_CMX)
497			dsp_cmx_debug(dsp);
498		break;
499	case DSP_DELAY: /* use delay algorithm instead of dynamic
500			   jitter algorithm */
501		if (dsp->hdlc) {
502			ret = -EINVAL;
503			break;
504		}
505		if (len < sizeof(int)) {
506			ret = -EINVAL;
507			break;
508		}
509		dsp->cmx_delay = (*((int *)data)) << 3;
510		/* milliseconds to samples */
511		if (dsp->cmx_delay >= (CMX_BUFF_HALF >> 1))
512			/* clip to half of maximum usable buffer
513			   (half of half buffer) */
514			dsp->cmx_delay = (CMX_BUFF_HALF >> 1) - 1;
515		if (dsp_debug & DEBUG_DSP_CORE)
516			printk(KERN_DEBUG "%s: use delay algorithm to "
517			       "compensate jitter (%d samples)\n",
518			       __func__, dsp->cmx_delay);
519		break;
520	case DSP_JITTER: /* use dynamic jitter algorithm instead of
521			    delay algorithm */
522		if (dsp->hdlc) {
523			ret = -EINVAL;
524			break;
525		}
526		dsp->cmx_delay = 0;
527		if (dsp_debug & DEBUG_DSP_CORE)
528			printk(KERN_DEBUG "%s: use jitter algorithm to "
529			       "compensate jitter\n", __func__);
530		break;
531	case DSP_TX_DEJITTER: /* use dynamic jitter algorithm for tx-buffer */
532		if (dsp->hdlc) {
533			ret = -EINVAL;
534			break;
535		}
536		dsp->tx_dejitter = 1;
537		if (dsp_debug & DEBUG_DSP_CORE)
538			printk(KERN_DEBUG "%s: use dejitter on TX "
539			       "buffer\n", __func__);
540		break;
541	case DSP_TX_DEJ_OFF: /* use tx-buffer without dejittering*/
542		if (dsp->hdlc) {
543			ret = -EINVAL;
544			break;
545		}
546		dsp->tx_dejitter = 0;
547		if (dsp_debug & DEBUG_DSP_CORE)
548			printk(KERN_DEBUG "%s: use TX buffer without "
549			       "dejittering\n", __func__);
550		break;
551	case DSP_PIPELINE_CFG:
552		if (dsp->hdlc) {
553			ret = -EINVAL;
554			break;
555		}
556		if (len > 0 && ((char *)data)[len - 1]) {
557			printk(KERN_DEBUG "%s: pipeline config string "
558			       "is not NULL terminated!\n", __func__);
559			ret = -EINVAL;
560		} else {
561			dsp->pipeline.inuse = 1;
562			dsp_cmx_hardware(dsp->conf, dsp);
563			ret = dsp_pipeline_build(&dsp->pipeline,
564						 len > 0 ? data : NULL);
565			dsp_cmx_hardware(dsp->conf, dsp);
566			dsp_rx_off(dsp);
567		}
568		break;
569	case DSP_BF_ENABLE_KEY: /* turn blowfish on */
570		if (dsp->hdlc) {
571			ret = -EINVAL;
572			break;
573		}
574		if (len < 4 || len > 56) {
575			ret = -EINVAL;
576			break;
577		}
578		if (dsp_debug & DEBUG_DSP_CORE)
579			printk(KERN_DEBUG "%s: turn blowfish on (key "
580			       "not shown)\n", __func__);
581		ret = dsp_bf_init(dsp, (u8 *)data, len);
582		/* set new cont */
583		if (!ret)
584			cont = DSP_BF_ACCEPT;
585		else
586			cont = DSP_BF_REJECT;
587		/* send indication if it worked to set it */
588		nskb = _alloc_mISDN_skb(PH_CONTROL_IND, MISDN_ID_ANY,
589					sizeof(int), &cont, GFP_ATOMIC);
590		if (nskb) {
591			if (dsp->up) {
592				if (dsp->up->send(dsp->up, nskb))
593					dev_kfree_skb(nskb);
594			} else
595				dev_kfree_skb(nskb);
596		}
597		if (!ret) {
598			dsp_cmx_hardware(dsp->conf, dsp);
599			dsp_dtmf_hardware(dsp);
600			dsp_rx_off(dsp);
601		}
602		break;
603	case DSP_BF_DISABLE: /* turn blowfish off */
604		if (dsp->hdlc) {
605			ret = -EINVAL;
606			break;
607		}
608		if (dsp_debug & DEBUG_DSP_CORE)
609			printk(KERN_DEBUG "%s: turn blowfish off\n", __func__);
610		dsp_bf_cleanup(dsp);
611		dsp_cmx_hardware(dsp->conf, dsp);
612		dsp_dtmf_hardware(dsp);
613		dsp_rx_off(dsp);
614		break;
615	default:
616		if (dsp_debug & DEBUG_DSP_CORE)
617			printk(KERN_DEBUG "%s: ctrl req %x unhandled\n",
618			       __func__, cont);
619		ret = -EINVAL;
620	}
621	return ret;
622}
623
624static void
625get_features(struct mISDNchannel *ch)
626{
627	struct dsp		*dsp = container_of(ch, struct dsp, ch);
628	struct mISDN_ctrl_req	cq;
629
630	if (!ch->peer) {
631		if (dsp_debug & DEBUG_DSP_CORE)
632			printk(KERN_DEBUG "%s: no peer, no features\n",
633			       __func__);
634		return;
635	}
636	memset(&cq, 0, sizeof(cq));
637	cq.op = MISDN_CTRL_GETOP;
638	if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq) < 0) {
639		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
640		       __func__);
641		return;
642	}
643	if (cq.op & MISDN_CTRL_RX_OFF)
644		dsp->features_rx_off = 1;
645	if (cq.op & MISDN_CTRL_FILL_EMPTY)
646		dsp->features_fill_empty = 1;
647	if (dsp_options & DSP_OPT_NOHARDWARE)
648		return;
649	if ((cq.op & MISDN_CTRL_HW_FEATURES_OP)) {
650		cq.op = MISDN_CTRL_HW_FEATURES;
651		*((u_long *)&cq.p1) = (u_long)&dsp->features;
652		if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq)) {
653			printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
654			       __func__);
655		}
656	} else
657		if (dsp_debug & DEBUG_DSP_CORE)
658			printk(KERN_DEBUG "%s: features not supported for %s\n",
659			       __func__, dsp->name);
660}
661
662static int
663dsp_function(struct mISDNchannel *ch,  struct sk_buff *skb)
664{
665	struct dsp		*dsp = container_of(ch, struct dsp, ch);
666	struct mISDNhead	*hh;
667	int			ret = 0;
668	u8			*digits = NULL;
669	u_long			flags;
670
671	hh = mISDN_HEAD_P(skb);
672	switch (hh->prim) {
673		/* FROM DOWN */
674	case (PH_DATA_CNF):
675		dsp->data_pending = 0;
676		/* trigger next hdlc frame, if any */
677		if (dsp->hdlc) {
678			spin_lock_irqsave(&dsp_lock, flags);
679			if (dsp->b_active)
680				schedule_work(&dsp->workq);
681			spin_unlock_irqrestore(&dsp_lock, flags);
682		}
683		break;
684	case (PH_DATA_IND):
685	case (DL_DATA_IND):
686		if (skb->len < 1) {
687			ret = -EINVAL;
688			break;
689		}
690		if (dsp->rx_is_off) {
691			if (dsp_debug & DEBUG_DSP_CORE)
692				printk(KERN_DEBUG "%s: rx-data during rx_off"
693				       " for %s\n",
694				       __func__, dsp->name);
695		}
696		if (dsp->hdlc) {
697			/* hdlc */
698			spin_lock_irqsave(&dsp_lock, flags);
699			dsp_cmx_hdlc(dsp, skb);
700			spin_unlock_irqrestore(&dsp_lock, flags);
701			if (dsp->rx_disabled) {
702				/* if receive is not allowed */
703				break;
704			}
705			hh->prim = DL_DATA_IND;
706			if (dsp->up)
707				return dsp->up->send(dsp->up, skb);
708			break;
709		}
710
711		spin_lock_irqsave(&dsp_lock, flags);
712
713		/* decrypt if enabled */
714		if (dsp->bf_enable)
715			dsp_bf_decrypt(dsp, skb->data, skb->len);
716		/* pipeline */
717		if (dsp->pipeline.inuse)
718			dsp_pipeline_process_rx(&dsp->pipeline, skb->data,
719						skb->len, hh->id);
720		/* change volume if requested */
721		if (dsp->rx_volume)
722			dsp_change_volume(skb, dsp->rx_volume);
723		/* check if dtmf soft decoding is turned on */
724		if (dsp->dtmf.software) {
725			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
726							  skb->len, (dsp_options & DSP_OPT_ULAW) ? 1 : 0);
727		}
728		/* we need to process receive data if software */
729		if (dsp->conf && dsp->conf->software) {
730			/* process data from card at cmx */
731			dsp_cmx_receive(dsp, skb);
732		}
733
734		spin_unlock_irqrestore(&dsp_lock, flags);
735
736		/* send dtmf result, if any */
737		if (digits) {
738			while (*digits) {
739				int k;
740				struct sk_buff *nskb;
741				if (dsp_debug & DEBUG_DSP_DTMF)
742					printk(KERN_DEBUG "%s: digit"
743					       "(%c) to layer %s\n",
744					       __func__, *digits, dsp->name);
745				k = *digits | DTMF_TONE_VAL;
746				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
747							MISDN_ID_ANY, sizeof(int), &k,
748							GFP_ATOMIC);
749				if (nskb) {
750					if (dsp->up) {
751						if (dsp->up->send(
752							    dsp->up, nskb))
753							dev_kfree_skb(nskb);
754					} else
755						dev_kfree_skb(nskb);
756				}
757				digits++;
758			}
759		}
760		if (dsp->rx_disabled) {
761			/* if receive is not allowed */
762			break;
763		}
764		hh->prim = DL_DATA_IND;
765		if (dsp->up)
766			return dsp->up->send(dsp->up, skb);
767		break;
768	case (PH_CONTROL_IND):
769		if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
770			printk(KERN_DEBUG "%s: PH_CONTROL INDICATION "
771			       "received: %x (len %d) %s\n", __func__,
772			       hh->id, skb->len, dsp->name);
773		switch (hh->id) {
774		case (DTMF_HFC_COEF): /* getting coefficients */
775			if (!dsp->dtmf.hardware) {
776				if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
777					printk(KERN_DEBUG "%s: ignoring DTMF "
778					       "coefficients from HFC\n",
779					       __func__);
780				break;
781			}
782			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
783							  skb->len, 2);
784			while (*digits) {
785				int k;
786				struct sk_buff *nskb;
787				if (dsp_debug & DEBUG_DSP_DTMF)
788					printk(KERN_DEBUG "%s: digit"
789					       "(%c) to layer %s\n",
790					       __func__, *digits, dsp->name);
791				k = *digits | DTMF_TONE_VAL;
792				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
793							MISDN_ID_ANY, sizeof(int), &k,
794							GFP_ATOMIC);
795				if (nskb) {
796					if (dsp->up) {
797						if (dsp->up->send(
798							    dsp->up, nskb))
799							dev_kfree_skb(nskb);
800					} else
801						dev_kfree_skb(nskb);
802				}
803				digits++;
804			}
805			break;
806		case (HFC_VOL_CHANGE_TX): /* change volume */
807			if (skb->len != sizeof(int)) {
808				ret = -EINVAL;
809				break;
810			}
811			spin_lock_irqsave(&dsp_lock, flags);
812			dsp->tx_volume = *((int *)skb->data);
813			if (dsp_debug & DEBUG_DSP_CORE)
814				printk(KERN_DEBUG "%s: change tx volume to "
815				       "%d\n", __func__, dsp->tx_volume);
816			dsp_cmx_hardware(dsp->conf, dsp);
817			dsp_dtmf_hardware(dsp);
818			dsp_rx_off(dsp);
819			spin_unlock_irqrestore(&dsp_lock, flags);
820			break;
821		default:
822			if (dsp_debug & DEBUG_DSP_CORE)
823				printk(KERN_DEBUG "%s: ctrl ind %x unhandled "
824				       "%s\n", __func__, hh->id, dsp->name);
825			ret = -EINVAL;
826		}
827		break;
828	case (PH_ACTIVATE_IND):
829	case (PH_ACTIVATE_CNF):
830		if (dsp_debug & DEBUG_DSP_CORE)
831			printk(KERN_DEBUG "%s: b_channel is now active %s\n",
832			       __func__, dsp->name);
833		/* bchannel now active */
834		spin_lock_irqsave(&dsp_lock, flags);
835		dsp->b_active = 1;
836		dsp->data_pending = 0;
837		dsp->rx_init = 1;
838		/* rx_W and rx_R will be adjusted on first frame */
839		dsp->rx_W = 0;
840		dsp->rx_R = 0;
841		memset(dsp->rx_buff, 0, sizeof(dsp->rx_buff));
842		dsp_cmx_hardware(dsp->conf, dsp);
843		dsp_dtmf_hardware(dsp);
844		dsp_rx_off(dsp);
845		spin_unlock_irqrestore(&dsp_lock, flags);
846		if (dsp_debug & DEBUG_DSP_CORE)
847			printk(KERN_DEBUG "%s: done with activation, sending "
848			       "confirm to user space. %s\n", __func__,
849			       dsp->name);
850		/* send activation to upper layer */
851		hh->prim = DL_ESTABLISH_CNF;
852		if (dsp->up)
853			return dsp->up->send(dsp->up, skb);
854		break;
855	case (PH_DEACTIVATE_IND):
856	case (PH_DEACTIVATE_CNF):
857		if (dsp_debug & DEBUG_DSP_CORE)
858			printk(KERN_DEBUG "%s: b_channel is now inactive %s\n",
859			       __func__, dsp->name);
860		/* bchannel now inactive */
861		spin_lock_irqsave(&dsp_lock, flags);
862		dsp->b_active = 0;
863		dsp->data_pending = 0;
864		dsp_cmx_hardware(dsp->conf, dsp);
865		dsp_rx_off(dsp);
866		spin_unlock_irqrestore(&dsp_lock, flags);
867		hh->prim = DL_RELEASE_CNF;
868		if (dsp->up)
869			return dsp->up->send(dsp->up, skb);
870		break;
871		/* FROM UP */
872	case (DL_DATA_REQ):
873	case (PH_DATA_REQ):
874		if (skb->len < 1) {
875			ret = -EINVAL;
876			break;
877		}
878		if (dsp->hdlc) {
879			/* hdlc */
880			if (!dsp->b_active) {
881				ret = -EIO;
882				break;
883			}
884			hh->prim = PH_DATA_REQ;
885			spin_lock_irqsave(&dsp_lock, flags);
886			skb_queue_tail(&dsp->sendq, skb);
887			schedule_work(&dsp->workq);
888			spin_unlock_irqrestore(&dsp_lock, flags);
889			return 0;
890		}
891		/* send data to tx-buffer (if no tone is played) */
892		if (!dsp->tone.tone) {
893			spin_lock_irqsave(&dsp_lock, flags);
894			dsp_cmx_transmit(dsp, skb);
895			spin_unlock_irqrestore(&dsp_lock, flags);
896		}
897		break;
898	case (PH_CONTROL_REQ):
899		spin_lock_irqsave(&dsp_lock, flags);
900		ret = dsp_control_req(dsp, hh, skb);
901		spin_unlock_irqrestore(&dsp_lock, flags);
902		break;
903	case (DL_ESTABLISH_REQ):
904	case (PH_ACTIVATE_REQ):
905		if (dsp_debug & DEBUG_DSP_CORE)
906			printk(KERN_DEBUG "%s: activating b_channel %s\n",
907			       __func__, dsp->name);
908		if (dsp->dtmf.hardware || dsp->dtmf.software)
909			dsp_dtmf_goertzel_init(dsp);
910		get_features(ch);
911		/* enable fill_empty feature */
912		if (dsp->features_fill_empty)
913			dsp_fill_empty(dsp);
914		/* send ph_activate */
915		hh->prim = PH_ACTIVATE_REQ;
916		if (ch->peer)
917			return ch->recv(ch->peer, skb);
918		break;
919	case (DL_RELEASE_REQ):
920	case (PH_DEACTIVATE_REQ):
921		if (dsp_debug & DEBUG_DSP_CORE)
922			printk(KERN_DEBUG "%s: releasing b_channel %s\n",
923			       __func__, dsp->name);
924		spin_lock_irqsave(&dsp_lock, flags);
925		dsp->tone.tone = 0;
926		dsp->tone.hardware = 0;
927		dsp->tone.software = 0;
928		if (timer_pending(&dsp->tone.tl))
929			del_timer(&dsp->tone.tl);
930		if (dsp->conf)
931			dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be
932						 called here */
933		skb_queue_purge(&dsp->sendq);
934		spin_unlock_irqrestore(&dsp_lock, flags);
935		hh->prim = PH_DEACTIVATE_REQ;
936		if (ch->peer)
937			return ch->recv(ch->peer, skb);
938		break;
939	default:
940		if (dsp_debug & DEBUG_DSP_CORE)
941			printk(KERN_DEBUG "%s: msg %x unhandled %s\n",
942			       __func__, hh->prim, dsp->name);
943		ret = -EINVAL;
944	}
945	if (!ret)
946		dev_kfree_skb(skb);
947	return ret;
948}
949
950static int
951dsp_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
952{
953	struct dsp		*dsp = container_of(ch, struct dsp, ch);
954	u_long		flags;
955	int		err = 0;
956
957	if (debug & DEBUG_DSP_CTRL)
958		printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
959
960	switch (cmd) {
961	case OPEN_CHANNEL:
962		break;
963	case CLOSE_CHANNEL:
964		if (dsp->ch.peer)
965			dsp->ch.peer->ctrl(dsp->ch.peer, CLOSE_CHANNEL, NULL);
966
967		/* wait until workqueue has finished,
968		 * must lock here, or we may hit send-process currently
969		 * queueing. */
970		spin_lock_irqsave(&dsp_lock, flags);
971		dsp->b_active = 0;
972		spin_unlock_irqrestore(&dsp_lock, flags);
973		/* MUST not be locked, because it waits until queue is done. */
974		cancel_work_sync(&dsp->workq);
975		spin_lock_irqsave(&dsp_lock, flags);
976		if (timer_pending(&dsp->tone.tl))
977			del_timer(&dsp->tone.tl);
978		skb_queue_purge(&dsp->sendq);
979		if (dsp_debug & DEBUG_DSP_CTRL)
980			printk(KERN_DEBUG "%s: releasing member %s\n",
981			       __func__, dsp->name);
982		dsp->b_active = 0;
983		dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be called
984					 here */
985		dsp_pipeline_destroy(&dsp->pipeline);
986
987		if (dsp_debug & DEBUG_DSP_CTRL)
988			printk(KERN_DEBUG "%s: remove & destroy object %s\n",
989			       __func__, dsp->name);
990		list_del(&dsp->list);
991		spin_unlock_irqrestore(&dsp_lock, flags);
992
993		if (dsp_debug & DEBUG_DSP_CTRL)
994			printk(KERN_DEBUG "%s: dsp instance released\n",
995			       __func__);
996		vfree(dsp);
997		module_put(THIS_MODULE);
998		break;
999	}
1000	return err;
1001}
1002
1003static void
1004dsp_send_bh(struct work_struct *work)
1005{
1006	struct dsp *dsp = container_of(work, struct dsp, workq);
1007	struct sk_buff *skb;
1008	struct mISDNhead	*hh;
1009
1010	if (dsp->hdlc && dsp->data_pending)
1011		return; /* wait until data has been acknowledged */
1012
1013	/* send queued data */
1014	while ((skb = skb_dequeue(&dsp->sendq))) {
1015		/* in locked date, we must have still data in queue */
1016		if (dsp->data_pending) {
1017			if (dsp_debug & DEBUG_DSP_CORE)
1018				printk(KERN_DEBUG "%s: fifo full %s, this is "
1019				       "no bug!\n", __func__, dsp->name);
1020			/* flush transparent data, if not acked */
1021			dev_kfree_skb(skb);
1022			continue;
1023		}
1024		hh = mISDN_HEAD_P(skb);
1025		if (hh->prim == DL_DATA_REQ) {
1026			/* send packet up */
1027			if (dsp->up) {
1028				if (dsp->up->send(dsp->up, skb))
1029					dev_kfree_skb(skb);
1030			} else
1031				dev_kfree_skb(skb);
1032		} else {
1033			/* send packet down */
1034			if (dsp->ch.peer) {
1035				dsp->data_pending = 1;
1036				if (dsp->ch.recv(dsp->ch.peer, skb)) {
1037					dev_kfree_skb(skb);
1038					dsp->data_pending = 0;
1039				}
1040			} else
1041				dev_kfree_skb(skb);
1042		}
1043	}
1044}
1045
1046static int
1047dspcreate(struct channel_req *crq)
1048{
1049	struct dsp		*ndsp;
1050	u_long		flags;
1051
1052	if (crq->protocol != ISDN_P_B_L2DSP
1053	    && crq->protocol != ISDN_P_B_L2DSPHDLC)
1054		return -EPROTONOSUPPORT;
1055	ndsp = vzalloc(sizeof(struct dsp));
1056	if (!ndsp) {
1057		printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
1058		return -ENOMEM;
1059	}
1060	if (dsp_debug & DEBUG_DSP_CTRL)
1061		printk(KERN_DEBUG "%s: creating new dsp instance\n", __func__);
1062
1063	/* default enabled */
1064	INIT_WORK(&ndsp->workq, (void *)dsp_send_bh);
1065	skb_queue_head_init(&ndsp->sendq);
1066	ndsp->ch.send = dsp_function;
1067	ndsp->ch.ctrl = dsp_ctrl;
1068	ndsp->up = crq->ch;
1069	crq->ch = &ndsp->ch;
1070	if (crq->protocol == ISDN_P_B_L2DSP) {
1071		crq->protocol = ISDN_P_B_RAW;
1072		ndsp->hdlc = 0;
1073	} else {
1074		crq->protocol = ISDN_P_B_HDLC;
1075		ndsp->hdlc = 1;
1076	}
1077	if (!try_module_get(THIS_MODULE))
1078		printk(KERN_WARNING "%s:cannot get module\n",
1079		       __func__);
1080
1081	sprintf(ndsp->name, "DSP_C%x(0x%p)",
1082		ndsp->up->st->dev->id + 1, ndsp);
1083	/* set frame size to start */
1084	ndsp->features.hfc_id = -1; /* current PCM id */
1085	ndsp->features.pcm_id = -1; /* current PCM id */
1086	ndsp->pcm_slot_rx = -1; /* current CPM slot */
1087	ndsp->pcm_slot_tx = -1;
1088	ndsp->pcm_bank_rx = -1;
1089	ndsp->pcm_bank_tx = -1;
1090	ndsp->hfc_conf = -1; /* current conference number */
1091	/* set tone timer */
1092	ndsp->tone.tl.function = (void *)dsp_tone_timeout;
1093	ndsp->tone.tl.data = (long) ndsp;
1094	init_timer(&ndsp->tone.tl);
1095
1096	if (dtmfthreshold < 20 || dtmfthreshold > 500)
1097		dtmfthreshold = 200;
1098	ndsp->dtmf.treshold = dtmfthreshold * 10000;
1099
1100	/* init pipeline append to list */
1101	spin_lock_irqsave(&dsp_lock, flags);
1102	dsp_pipeline_init(&ndsp->pipeline);
1103	list_add_tail(&ndsp->list, &dsp_ilist);
1104	spin_unlock_irqrestore(&dsp_lock, flags);
1105
1106	return 0;
1107}
1108
1109
1110static struct Bprotocol DSP = {
1111	.Bprotocols = (1 << (ISDN_P_B_L2DSP & ISDN_P_B_MASK))
1112	| (1 << (ISDN_P_B_L2DSPHDLC & ISDN_P_B_MASK)),
1113	.name = "dsp",
1114	.create = dspcreate
1115};
1116
1117static int __init dsp_init(void)
1118{
1119	int err;
1120	int tics;
1121
1122	printk(KERN_INFO "DSP module %s\n", mISDN_dsp_revision);
1123
1124	dsp_options = options;
1125	dsp_debug = debug;
1126
1127	/* set packet size */
1128	dsp_poll = poll;
1129	if (dsp_poll) {
1130		if (dsp_poll > MAX_POLL) {
1131			printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
1132			       "maximum.\n", __func__, poll, MAX_POLL);
1133			err = -EINVAL;
1134			return err;
1135		}
1136		if (dsp_poll < 8) {
1137			printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
1138			       "minimum.\n", __func__, dsp_poll);
1139			err = -EINVAL;
1140			return err;
1141		}
1142		dsp_tics = poll * HZ / 8000;
1143		if (dsp_tics * 8000 != poll * HZ) {
1144			printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
1145			       "samples (0,125 ms). It is not a multiple of "
1146			       "%d HZ.\n", poll, HZ);
1147			err = -EINVAL;
1148			return err;
1149		}
1150	} else {
1151		poll = 8;
1152		while (poll <= MAX_POLL) {
1153			tics = (poll * HZ) / 8000;
1154			if (tics * 8000 == poll * HZ) {
1155				dsp_tics = tics;
1156				dsp_poll = poll;
1157				if (poll >= 64)
1158					break;
1159			}
1160			poll++;
1161		}
1162	}
1163	if (dsp_poll == 0) {
1164		printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
1165		       "clock that equals exactly the duration of 8-256 "
1166		       "samples. (Choose kernel clock speed like 100, 250, "
1167		       "300, 1000)\n");
1168		err = -EINVAL;
1169		return err;
1170	}
1171	printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
1172	       "%d jiffies.\n", dsp_poll, dsp_tics);
1173
1174	spin_lock_init(&dsp_lock);
1175	INIT_LIST_HEAD(&dsp_ilist);
1176	INIT_LIST_HEAD(&conf_ilist);
1177
1178	/* init conversion tables */
1179	dsp_audio_generate_law_tables();
1180	dsp_silence = (dsp_options & DSP_OPT_ULAW) ? 0xff : 0x2a;
1181	dsp_audio_law_to_s32 = (dsp_options & DSP_OPT_ULAW) ?
1182		dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
1183	dsp_audio_generate_s2law_table();
1184	dsp_audio_generate_seven();
1185	dsp_audio_generate_mix_table();
1186	if (dsp_options & DSP_OPT_ULAW)
1187		dsp_audio_generate_ulaw_samples();
1188	dsp_audio_generate_volume_changes();
1189
1190	err = dsp_pipeline_module_init();
1191	if (err) {
1192		printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
1193		       "error(%d)\n", err);
1194		return err;
1195	}
1196
1197	err = mISDN_register_Bprotocol(&DSP);
1198	if (err) {
1199		printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
1200		return err;
1201	}
1202
1203	/* set sample timer */
1204	dsp_spl_tl.function = (void *)dsp_cmx_send;
1205	dsp_spl_tl.data = 0;
1206	init_timer(&dsp_spl_tl);
1207	dsp_spl_tl.expires = jiffies + dsp_tics;
1208	dsp_spl_jiffies = dsp_spl_tl.expires;
1209	add_timer(&dsp_spl_tl);
1210
1211	return 0;
1212}
1213
1214
1215static void __exit dsp_cleanup(void)
1216{
1217	mISDN_unregister_Bprotocol(&DSP);
1218
1219	if (timer_pending(&dsp_spl_tl))
1220		del_timer(&dsp_spl_tl);
1221
1222	if (!list_empty(&dsp_ilist)) {
1223		printk(KERN_ERR "mISDN_dsp: Audio DSP object inst list not "
1224		       "empty.\n");
1225	}
1226	if (!list_empty(&conf_ilist)) {
1227		printk(KERN_ERR "mISDN_dsp: Conference list not empty. Not "
1228		       "all memory freed.\n");
1229	}
1230
1231	dsp_pipeline_module_exit();
1232}
1233
1234module_init(dsp_init);
1235module_exit(dsp_cleanup);
1236