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	cq.p2 = dsp_silence;
272	if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
273		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
274		       __func__);
275		return;
276	}
277	if (dsp_debug & DEBUG_DSP_CORE)
278		printk(KERN_DEBUG "%s: %s set fill_empty = 1\n",
279		       __func__, dsp->name);
280}
281
282static int
283dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
284{
285	struct sk_buff	*nskb;
286	int ret = 0;
287	int cont;
288	u8 *data;
289	int len;
290
291	if (skb->len < sizeof(int)) {
292		printk(KERN_ERR "%s: PH_CONTROL message too short\n", __func__);
293		return -EINVAL;
294	}
295	cont = *((int *)skb->data);
296	len = skb->len - sizeof(int);
297	data = skb->data + sizeof(int);
298
299	switch (cont) {
300	case DTMF_TONE_START: /* turn on DTMF */
301		if (dsp->hdlc) {
302			ret = -EINVAL;
303			break;
304		}
305		if (dsp_debug & DEBUG_DSP_CORE)
306			printk(KERN_DEBUG "%s: start dtmf\n", __func__);
307		if (len == sizeof(int)) {
308			if (dsp_debug & DEBUG_DSP_CORE)
309				printk(KERN_NOTICE "changing DTMF Threshold "
310				       "to %d\n", *((int *)data));
311			dsp->dtmf.treshold = (*(int *)data) * 10000;
312		}
313		dsp->dtmf.enable = 1;
314		/* init goertzel */
315		dsp_dtmf_goertzel_init(dsp);
316
317		/* check dtmf hardware */
318		dsp_dtmf_hardware(dsp);
319		dsp_rx_off(dsp);
320		break;
321	case DTMF_TONE_STOP: /* turn off DTMF */
322		if (dsp_debug & DEBUG_DSP_CORE)
323			printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
324		dsp->dtmf.enable = 0;
325		dsp->dtmf.hardware = 0;
326		dsp->dtmf.software = 0;
327		break;
328	case DSP_CONF_JOIN: /* join / update conference */
329		if (len < sizeof(int)) {
330			ret = -EINVAL;
331			break;
332		}
333		if (*((u32 *)data) == 0)
334			goto conf_split;
335		if (dsp_debug & DEBUG_DSP_CORE)
336			printk(KERN_DEBUG "%s: join conference %d\n",
337			       __func__, *((u32 *)data));
338		ret = dsp_cmx_conf(dsp, *((u32 *)data));
339		/* dsp_cmx_hardware will also be called here */
340		dsp_rx_off(dsp);
341		if (dsp_debug & DEBUG_DSP_CMX)
342			dsp_cmx_debug(dsp);
343		break;
344	case DSP_CONF_SPLIT: /* remove from conference */
345	conf_split:
346		if (dsp_debug & DEBUG_DSP_CORE)
347			printk(KERN_DEBUG "%s: release conference\n", __func__);
348		ret = dsp_cmx_conf(dsp, 0);
349		/* dsp_cmx_hardware will also be called here */
350		if (dsp_debug & DEBUG_DSP_CMX)
351			dsp_cmx_debug(dsp);
352		dsp_rx_off(dsp);
353		break;
354	case DSP_TONE_PATT_ON: /* play tone */
355		if (dsp->hdlc) {
356			ret = -EINVAL;
357			break;
358		}
359		if (len < sizeof(int)) {
360			ret = -EINVAL;
361			break;
362		}
363		if (dsp_debug & DEBUG_DSP_CORE)
364			printk(KERN_DEBUG "%s: turn tone 0x%x on\n",
365			       __func__, *((int *)skb->data));
366		ret = dsp_tone(dsp, *((int *)data));
367		if (!ret) {
368			dsp_cmx_hardware(dsp->conf, dsp);
369			dsp_rx_off(dsp);
370		}
371		if (!dsp->tone.tone)
372			goto tone_off;
373		break;
374	case DSP_TONE_PATT_OFF: /* stop tone */
375		if (dsp->hdlc) {
376			ret = -EINVAL;
377			break;
378		}
379		if (dsp_debug & DEBUG_DSP_CORE)
380			printk(KERN_DEBUG "%s: turn tone off\n", __func__);
381		dsp_tone(dsp, 0);
382		dsp_cmx_hardware(dsp->conf, dsp);
383		dsp_rx_off(dsp);
384		/* reset tx buffers (user space data) */
385	tone_off:
386		dsp->rx_W = 0;
387		dsp->rx_R = 0;
388		break;
389	case DSP_VOL_CHANGE_TX: /* change volume */
390		if (dsp->hdlc) {
391			ret = -EINVAL;
392			break;
393		}
394		if (len < sizeof(int)) {
395			ret = -EINVAL;
396			break;
397		}
398		dsp->tx_volume = *((int *)data);
399		if (dsp_debug & DEBUG_DSP_CORE)
400			printk(KERN_DEBUG "%s: change tx vol to %d\n",
401			       __func__, dsp->tx_volume);
402		dsp_cmx_hardware(dsp->conf, dsp);
403		dsp_dtmf_hardware(dsp);
404		dsp_rx_off(dsp);
405		break;
406	case DSP_VOL_CHANGE_RX: /* change volume */
407		if (dsp->hdlc) {
408			ret = -EINVAL;
409			break;
410		}
411		if (len < sizeof(int)) {
412			ret = -EINVAL;
413			break;
414		}
415		dsp->rx_volume = *((int *)data);
416		if (dsp_debug & DEBUG_DSP_CORE)
417			printk(KERN_DEBUG "%s: change rx vol to %d\n",
418			       __func__, dsp->tx_volume);
419		dsp_cmx_hardware(dsp->conf, dsp);
420		dsp_dtmf_hardware(dsp);
421		dsp_rx_off(dsp);
422		break;
423	case DSP_ECHO_ON: /* enable echo */
424		dsp->echo.software = 1; /* soft echo */
425		if (dsp_debug & DEBUG_DSP_CORE)
426			printk(KERN_DEBUG "%s: enable cmx-echo\n", __func__);
427		dsp_cmx_hardware(dsp->conf, dsp);
428		dsp_rx_off(dsp);
429		if (dsp_debug & DEBUG_DSP_CMX)
430			dsp_cmx_debug(dsp);
431		break;
432	case DSP_ECHO_OFF: /* disable echo */
433		dsp->echo.software = 0;
434		dsp->echo.hardware = 0;
435		if (dsp_debug & DEBUG_DSP_CORE)
436			printk(KERN_DEBUG "%s: disable cmx-echo\n", __func__);
437		dsp_cmx_hardware(dsp->conf, dsp);
438		dsp_rx_off(dsp);
439		if (dsp_debug & DEBUG_DSP_CMX)
440			dsp_cmx_debug(dsp);
441		break;
442	case DSP_RECEIVE_ON: /* enable receive to user space */
443		if (dsp_debug & DEBUG_DSP_CORE)
444			printk(KERN_DEBUG "%s: enable receive to user "
445			       "space\n", __func__);
446		dsp->rx_disabled = 0;
447		dsp_rx_off(dsp);
448		break;
449	case DSP_RECEIVE_OFF: /* disable receive to user space */
450		if (dsp_debug & DEBUG_DSP_CORE)
451			printk(KERN_DEBUG "%s: disable receive to "
452			       "user space\n", __func__);
453		dsp->rx_disabled = 1;
454		dsp_rx_off(dsp);
455		break;
456	case DSP_MIX_ON: /* enable mixing of tx data */
457		if (dsp->hdlc) {
458			ret = -EINVAL;
459			break;
460		}
461		if (dsp_debug & DEBUG_DSP_CORE)
462			printk(KERN_DEBUG "%s: enable mixing of "
463			       "tx-data with conf members\n", __func__);
464		dsp->tx_mix = 1;
465		dsp_cmx_hardware(dsp->conf, dsp);
466		dsp_rx_off(dsp);
467		if (dsp_debug & DEBUG_DSP_CMX)
468			dsp_cmx_debug(dsp);
469		break;
470	case DSP_MIX_OFF: /* disable mixing of tx data */
471		if (dsp->hdlc) {
472			ret = -EINVAL;
473			break;
474		}
475		if (dsp_debug & DEBUG_DSP_CORE)
476			printk(KERN_DEBUG "%s: disable mixing of "
477			       "tx-data with conf members\n", __func__);
478		dsp->tx_mix = 0;
479		dsp_cmx_hardware(dsp->conf, dsp);
480		dsp_rx_off(dsp);
481		if (dsp_debug & DEBUG_DSP_CMX)
482			dsp_cmx_debug(dsp);
483		break;
484	case DSP_TXDATA_ON: /* enable txdata */
485		dsp->tx_data = 1;
486		if (dsp_debug & DEBUG_DSP_CORE)
487			printk(KERN_DEBUG "%s: enable tx-data\n", __func__);
488		dsp_cmx_hardware(dsp->conf, dsp);
489		dsp_rx_off(dsp);
490		if (dsp_debug & DEBUG_DSP_CMX)
491			dsp_cmx_debug(dsp);
492		break;
493	case DSP_TXDATA_OFF: /* disable txdata */
494		dsp->tx_data = 0;
495		if (dsp_debug & DEBUG_DSP_CORE)
496			printk(KERN_DEBUG "%s: disable tx-data\n", __func__);
497		dsp_cmx_hardware(dsp->conf, dsp);
498		dsp_rx_off(dsp);
499		if (dsp_debug & DEBUG_DSP_CMX)
500			dsp_cmx_debug(dsp);
501		break;
502	case DSP_DELAY: /* use delay algorithm instead of dynamic
503			   jitter algorithm */
504		if (dsp->hdlc) {
505			ret = -EINVAL;
506			break;
507		}
508		if (len < sizeof(int)) {
509			ret = -EINVAL;
510			break;
511		}
512		dsp->cmx_delay = (*((int *)data)) << 3;
513		/* milliseconds to samples */
514		if (dsp->cmx_delay >= (CMX_BUFF_HALF >> 1))
515			/* clip to half of maximum usable buffer
516			   (half of half buffer) */
517			dsp->cmx_delay = (CMX_BUFF_HALF >> 1) - 1;
518		if (dsp_debug & DEBUG_DSP_CORE)
519			printk(KERN_DEBUG "%s: use delay algorithm to "
520			       "compensate jitter (%d samples)\n",
521			       __func__, dsp->cmx_delay);
522		break;
523	case DSP_JITTER: /* use dynamic jitter algorithm instead of
524			    delay algorithm */
525		if (dsp->hdlc) {
526			ret = -EINVAL;
527			break;
528		}
529		dsp->cmx_delay = 0;
530		if (dsp_debug & DEBUG_DSP_CORE)
531			printk(KERN_DEBUG "%s: use jitter algorithm to "
532			       "compensate jitter\n", __func__);
533		break;
534	case DSP_TX_DEJITTER: /* use dynamic jitter algorithm for tx-buffer */
535		if (dsp->hdlc) {
536			ret = -EINVAL;
537			break;
538		}
539		dsp->tx_dejitter = 1;
540		if (dsp_debug & DEBUG_DSP_CORE)
541			printk(KERN_DEBUG "%s: use dejitter on TX "
542			       "buffer\n", __func__);
543		break;
544	case DSP_TX_DEJ_OFF: /* use tx-buffer without dejittering*/
545		if (dsp->hdlc) {
546			ret = -EINVAL;
547			break;
548		}
549		dsp->tx_dejitter = 0;
550		if (dsp_debug & DEBUG_DSP_CORE)
551			printk(KERN_DEBUG "%s: use TX buffer without "
552			       "dejittering\n", __func__);
553		break;
554	case DSP_PIPELINE_CFG:
555		if (dsp->hdlc) {
556			ret = -EINVAL;
557			break;
558		}
559		if (len > 0 && ((char *)data)[len - 1]) {
560			printk(KERN_DEBUG "%s: pipeline config string "
561			       "is not NULL terminated!\n", __func__);
562			ret = -EINVAL;
563		} else {
564			dsp->pipeline.inuse = 1;
565			dsp_cmx_hardware(dsp->conf, dsp);
566			ret = dsp_pipeline_build(&dsp->pipeline,
567						 len > 0 ? data : NULL);
568			dsp_cmx_hardware(dsp->conf, dsp);
569			dsp_rx_off(dsp);
570		}
571		break;
572	case DSP_BF_ENABLE_KEY: /* turn blowfish on */
573		if (dsp->hdlc) {
574			ret = -EINVAL;
575			break;
576		}
577		if (len < 4 || len > 56) {
578			ret = -EINVAL;
579			break;
580		}
581		if (dsp_debug & DEBUG_DSP_CORE)
582			printk(KERN_DEBUG "%s: turn blowfish on (key "
583			       "not shown)\n", __func__);
584		ret = dsp_bf_init(dsp, (u8 *)data, len);
585		/* set new cont */
586		if (!ret)
587			cont = DSP_BF_ACCEPT;
588		else
589			cont = DSP_BF_REJECT;
590		/* send indication if it worked to set it */
591		nskb = _alloc_mISDN_skb(PH_CONTROL_IND, MISDN_ID_ANY,
592					sizeof(int), &cont, GFP_ATOMIC);
593		if (nskb) {
594			if (dsp->up) {
595				if (dsp->up->send(dsp->up, nskb))
596					dev_kfree_skb(nskb);
597			} else
598				dev_kfree_skb(nskb);
599		}
600		if (!ret) {
601			dsp_cmx_hardware(dsp->conf, dsp);
602			dsp_dtmf_hardware(dsp);
603			dsp_rx_off(dsp);
604		}
605		break;
606	case DSP_BF_DISABLE: /* turn blowfish off */
607		if (dsp->hdlc) {
608			ret = -EINVAL;
609			break;
610		}
611		if (dsp_debug & DEBUG_DSP_CORE)
612			printk(KERN_DEBUG "%s: turn blowfish off\n", __func__);
613		dsp_bf_cleanup(dsp);
614		dsp_cmx_hardware(dsp->conf, dsp);
615		dsp_dtmf_hardware(dsp);
616		dsp_rx_off(dsp);
617		break;
618	default:
619		if (dsp_debug & DEBUG_DSP_CORE)
620			printk(KERN_DEBUG "%s: ctrl req %x unhandled\n",
621			       __func__, cont);
622		ret = -EINVAL;
623	}
624	return ret;
625}
626
627static void
628get_features(struct mISDNchannel *ch)
629{
630	struct dsp		*dsp = container_of(ch, struct dsp, ch);
631	struct mISDN_ctrl_req	cq;
632
633	if (!ch->peer) {
634		if (dsp_debug & DEBUG_DSP_CORE)
635			printk(KERN_DEBUG "%s: no peer, no features\n",
636			       __func__);
637		return;
638	}
639	memset(&cq, 0, sizeof(cq));
640	cq.op = MISDN_CTRL_GETOP;
641	if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq) < 0) {
642		printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
643		       __func__);
644		return;
645	}
646	if (cq.op & MISDN_CTRL_RX_OFF)
647		dsp->features_rx_off = 1;
648	if (cq.op & MISDN_CTRL_FILL_EMPTY)
649		dsp->features_fill_empty = 1;
650	if (dsp_options & DSP_OPT_NOHARDWARE)
651		return;
652	if ((cq.op & MISDN_CTRL_HW_FEATURES_OP)) {
653		cq.op = MISDN_CTRL_HW_FEATURES;
654		*((u_long *)&cq.p1) = (u_long)&dsp->features;
655		if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq)) {
656			printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
657			       __func__);
658		}
659	} else
660		if (dsp_debug & DEBUG_DSP_CORE)
661			printk(KERN_DEBUG "%s: features not supported for %s\n",
662			       __func__, dsp->name);
663}
664
665static int
666dsp_function(struct mISDNchannel *ch,  struct sk_buff *skb)
667{
668	struct dsp		*dsp = container_of(ch, struct dsp, ch);
669	struct mISDNhead	*hh;
670	int			ret = 0;
671	u8			*digits = NULL;
672	u_long			flags;
673
674	hh = mISDN_HEAD_P(skb);
675	switch (hh->prim) {
676		/* FROM DOWN */
677	case (PH_DATA_CNF):
678		dsp->data_pending = 0;
679		/* trigger next hdlc frame, if any */
680		if (dsp->hdlc) {
681			spin_lock_irqsave(&dsp_lock, flags);
682			if (dsp->b_active)
683				schedule_work(&dsp->workq);
684			spin_unlock_irqrestore(&dsp_lock, flags);
685		}
686		break;
687	case (PH_DATA_IND):
688	case (DL_DATA_IND):
689		if (skb->len < 1) {
690			ret = -EINVAL;
691			break;
692		}
693		if (dsp->rx_is_off) {
694			if (dsp_debug & DEBUG_DSP_CORE)
695				printk(KERN_DEBUG "%s: rx-data during rx_off"
696				       " for %s\n",
697				       __func__, dsp->name);
698		}
699		if (dsp->hdlc) {
700			/* hdlc */
701			spin_lock_irqsave(&dsp_lock, flags);
702			dsp_cmx_hdlc(dsp, skb);
703			spin_unlock_irqrestore(&dsp_lock, flags);
704			if (dsp->rx_disabled) {
705				/* if receive is not allowed */
706				break;
707			}
708			hh->prim = DL_DATA_IND;
709			if (dsp->up)
710				return dsp->up->send(dsp->up, skb);
711			break;
712		}
713
714		spin_lock_irqsave(&dsp_lock, flags);
715
716		/* decrypt if enabled */
717		if (dsp->bf_enable)
718			dsp_bf_decrypt(dsp, skb->data, skb->len);
719		/* pipeline */
720		if (dsp->pipeline.inuse)
721			dsp_pipeline_process_rx(&dsp->pipeline, skb->data,
722						skb->len, hh->id);
723		/* change volume if requested */
724		if (dsp->rx_volume)
725			dsp_change_volume(skb, dsp->rx_volume);
726		/* check if dtmf soft decoding is turned on */
727		if (dsp->dtmf.software) {
728			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
729							  skb->len, (dsp_options & DSP_OPT_ULAW) ? 1 : 0);
730		}
731		/* we need to process receive data if software */
732		if (dsp->conf && dsp->conf->software) {
733			/* process data from card at cmx */
734			dsp_cmx_receive(dsp, skb);
735		}
736
737		spin_unlock_irqrestore(&dsp_lock, flags);
738
739		/* send dtmf result, if any */
740		if (digits) {
741			while (*digits) {
742				int k;
743				struct sk_buff *nskb;
744				if (dsp_debug & DEBUG_DSP_DTMF)
745					printk(KERN_DEBUG "%s: digit"
746					       "(%c) to layer %s\n",
747					       __func__, *digits, dsp->name);
748				k = *digits | DTMF_TONE_VAL;
749				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
750							MISDN_ID_ANY, sizeof(int), &k,
751							GFP_ATOMIC);
752				if (nskb) {
753					if (dsp->up) {
754						if (dsp->up->send(
755							    dsp->up, nskb))
756							dev_kfree_skb(nskb);
757					} else
758						dev_kfree_skb(nskb);
759				}
760				digits++;
761			}
762		}
763		if (dsp->rx_disabled) {
764			/* if receive is not allowed */
765			break;
766		}
767		hh->prim = DL_DATA_IND;
768		if (dsp->up)
769			return dsp->up->send(dsp->up, skb);
770		break;
771	case (PH_CONTROL_IND):
772		if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
773			printk(KERN_DEBUG "%s: PH_CONTROL INDICATION "
774			       "received: %x (len %d) %s\n", __func__,
775			       hh->id, skb->len, dsp->name);
776		switch (hh->id) {
777		case (DTMF_HFC_COEF): /* getting coefficients */
778			if (!dsp->dtmf.hardware) {
779				if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
780					printk(KERN_DEBUG "%s: ignoring DTMF "
781					       "coefficients from HFC\n",
782					       __func__);
783				break;
784			}
785			digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
786							  skb->len, 2);
787			while (*digits) {
788				int k;
789				struct sk_buff *nskb;
790				if (dsp_debug & DEBUG_DSP_DTMF)
791					printk(KERN_DEBUG "%s: digit"
792					       "(%c) to layer %s\n",
793					       __func__, *digits, dsp->name);
794				k = *digits | DTMF_TONE_VAL;
795				nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
796							MISDN_ID_ANY, sizeof(int), &k,
797							GFP_ATOMIC);
798				if (nskb) {
799					if (dsp->up) {
800						if (dsp->up->send(
801							    dsp->up, nskb))
802							dev_kfree_skb(nskb);
803					} else
804						dev_kfree_skb(nskb);
805				}
806				digits++;
807			}
808			break;
809		case (HFC_VOL_CHANGE_TX): /* change volume */
810			if (skb->len != sizeof(int)) {
811				ret = -EINVAL;
812				break;
813			}
814			spin_lock_irqsave(&dsp_lock, flags);
815			dsp->tx_volume = *((int *)skb->data);
816			if (dsp_debug & DEBUG_DSP_CORE)
817				printk(KERN_DEBUG "%s: change tx volume to "
818				       "%d\n", __func__, dsp->tx_volume);
819			dsp_cmx_hardware(dsp->conf, dsp);
820			dsp_dtmf_hardware(dsp);
821			dsp_rx_off(dsp);
822			spin_unlock_irqrestore(&dsp_lock, flags);
823			break;
824		default:
825			if (dsp_debug & DEBUG_DSP_CORE)
826				printk(KERN_DEBUG "%s: ctrl ind %x unhandled "
827				       "%s\n", __func__, hh->id, dsp->name);
828			ret = -EINVAL;
829		}
830		break;
831	case (PH_ACTIVATE_IND):
832	case (PH_ACTIVATE_CNF):
833		if (dsp_debug & DEBUG_DSP_CORE)
834			printk(KERN_DEBUG "%s: b_channel is now active %s\n",
835			       __func__, dsp->name);
836		/* bchannel now active */
837		spin_lock_irqsave(&dsp_lock, flags);
838		dsp->b_active = 1;
839		dsp->data_pending = 0;
840		dsp->rx_init = 1;
841		/* rx_W and rx_R will be adjusted on first frame */
842		dsp->rx_W = 0;
843		dsp->rx_R = 0;
844		memset(dsp->rx_buff, 0, sizeof(dsp->rx_buff));
845		dsp_cmx_hardware(dsp->conf, dsp);
846		dsp_dtmf_hardware(dsp);
847		dsp_rx_off(dsp);
848		spin_unlock_irqrestore(&dsp_lock, flags);
849		if (dsp_debug & DEBUG_DSP_CORE)
850			printk(KERN_DEBUG "%s: done with activation, sending "
851			       "confirm to user space. %s\n", __func__,
852			       dsp->name);
853		/* send activation to upper layer */
854		hh->prim = DL_ESTABLISH_CNF;
855		if (dsp->up)
856			return dsp->up->send(dsp->up, skb);
857		break;
858	case (PH_DEACTIVATE_IND):
859	case (PH_DEACTIVATE_CNF):
860		if (dsp_debug & DEBUG_DSP_CORE)
861			printk(KERN_DEBUG "%s: b_channel is now inactive %s\n",
862			       __func__, dsp->name);
863		/* bchannel now inactive */
864		spin_lock_irqsave(&dsp_lock, flags);
865		dsp->b_active = 0;
866		dsp->data_pending = 0;
867		dsp_cmx_hardware(dsp->conf, dsp);
868		dsp_rx_off(dsp);
869		spin_unlock_irqrestore(&dsp_lock, flags);
870		hh->prim = DL_RELEASE_CNF;
871		if (dsp->up)
872			return dsp->up->send(dsp->up, skb);
873		break;
874		/* FROM UP */
875	case (DL_DATA_REQ):
876	case (PH_DATA_REQ):
877		if (skb->len < 1) {
878			ret = -EINVAL;
879			break;
880		}
881		if (dsp->hdlc) {
882			/* hdlc */
883			if (!dsp->b_active) {
884				ret = -EIO;
885				break;
886			}
887			hh->prim = PH_DATA_REQ;
888			spin_lock_irqsave(&dsp_lock, flags);
889			skb_queue_tail(&dsp->sendq, skb);
890			schedule_work(&dsp->workq);
891			spin_unlock_irqrestore(&dsp_lock, flags);
892			return 0;
893		}
894		/* send data to tx-buffer (if no tone is played) */
895		if (!dsp->tone.tone) {
896			spin_lock_irqsave(&dsp_lock, flags);
897			dsp_cmx_transmit(dsp, skb);
898			spin_unlock_irqrestore(&dsp_lock, flags);
899		}
900		break;
901	case (PH_CONTROL_REQ):
902		spin_lock_irqsave(&dsp_lock, flags);
903		ret = dsp_control_req(dsp, hh, skb);
904		spin_unlock_irqrestore(&dsp_lock, flags);
905		break;
906	case (DL_ESTABLISH_REQ):
907	case (PH_ACTIVATE_REQ):
908		if (dsp_debug & DEBUG_DSP_CORE)
909			printk(KERN_DEBUG "%s: activating b_channel %s\n",
910			       __func__, dsp->name);
911		if (dsp->dtmf.hardware || dsp->dtmf.software)
912			dsp_dtmf_goertzel_init(dsp);
913		get_features(ch);
914		/* enable fill_empty feature */
915		if (dsp->features_fill_empty)
916			dsp_fill_empty(dsp);
917		/* send ph_activate */
918		hh->prim = PH_ACTIVATE_REQ;
919		if (ch->peer)
920			return ch->recv(ch->peer, skb);
921		break;
922	case (DL_RELEASE_REQ):
923	case (PH_DEACTIVATE_REQ):
924		if (dsp_debug & DEBUG_DSP_CORE)
925			printk(KERN_DEBUG "%s: releasing b_channel %s\n",
926			       __func__, dsp->name);
927		spin_lock_irqsave(&dsp_lock, flags);
928		dsp->tone.tone = 0;
929		dsp->tone.hardware = 0;
930		dsp->tone.software = 0;
931		if (timer_pending(&dsp->tone.tl))
932			del_timer(&dsp->tone.tl);
933		if (dsp->conf)
934			dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be
935						 called here */
936		skb_queue_purge(&dsp->sendq);
937		spin_unlock_irqrestore(&dsp_lock, flags);
938		hh->prim = PH_DEACTIVATE_REQ;
939		if (ch->peer)
940			return ch->recv(ch->peer, skb);
941		break;
942	default:
943		if (dsp_debug & DEBUG_DSP_CORE)
944			printk(KERN_DEBUG "%s: msg %x unhandled %s\n",
945			       __func__, hh->prim, dsp->name);
946		ret = -EINVAL;
947	}
948	if (!ret)
949		dev_kfree_skb(skb);
950	return ret;
951}
952
953static int
954dsp_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
955{
956	struct dsp		*dsp = container_of(ch, struct dsp, ch);
957	u_long		flags;
958	int		err = 0;
959
960	if (debug & DEBUG_DSP_CTRL)
961		printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
962
963	switch (cmd) {
964	case OPEN_CHANNEL:
965		break;
966	case CLOSE_CHANNEL:
967		if (dsp->ch.peer)
968			dsp->ch.peer->ctrl(dsp->ch.peer, CLOSE_CHANNEL, NULL);
969
970		/* wait until workqueue has finished,
971		 * must lock here, or we may hit send-process currently
972		 * queueing. */
973		spin_lock_irqsave(&dsp_lock, flags);
974		dsp->b_active = 0;
975		spin_unlock_irqrestore(&dsp_lock, flags);
976		/* MUST not be locked, because it waits until queue is done. */
977		cancel_work_sync(&dsp->workq);
978		spin_lock_irqsave(&dsp_lock, flags);
979		if (timer_pending(&dsp->tone.tl))
980			del_timer(&dsp->tone.tl);
981		skb_queue_purge(&dsp->sendq);
982		if (dsp_debug & DEBUG_DSP_CTRL)
983			printk(KERN_DEBUG "%s: releasing member %s\n",
984			       __func__, dsp->name);
985		dsp->b_active = 0;
986		dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be called
987					 here */
988		dsp_pipeline_destroy(&dsp->pipeline);
989
990		if (dsp_debug & DEBUG_DSP_CTRL)
991			printk(KERN_DEBUG "%s: remove & destroy object %s\n",
992			       __func__, dsp->name);
993		list_del(&dsp->list);
994		spin_unlock_irqrestore(&dsp_lock, flags);
995
996		if (dsp_debug & DEBUG_DSP_CTRL)
997			printk(KERN_DEBUG "%s: dsp instance released\n",
998			       __func__);
999		vfree(dsp);
1000		module_put(THIS_MODULE);
1001		break;
1002	}
1003	return err;
1004}
1005
1006static void
1007dsp_send_bh(struct work_struct *work)
1008{
1009	struct dsp *dsp = container_of(work, struct dsp, workq);
1010	struct sk_buff *skb;
1011	struct mISDNhead	*hh;
1012
1013	if (dsp->hdlc && dsp->data_pending)
1014		return; /* wait until data has been acknowledged */
1015
1016	/* send queued data */
1017	while ((skb = skb_dequeue(&dsp->sendq))) {
1018		/* in locked date, we must have still data in queue */
1019		if (dsp->data_pending) {
1020			if (dsp_debug & DEBUG_DSP_CORE)
1021				printk(KERN_DEBUG "%s: fifo full %s, this is "
1022				       "no bug!\n", __func__, dsp->name);
1023			/* flush transparent data, if not acked */
1024			dev_kfree_skb(skb);
1025			continue;
1026		}
1027		hh = mISDN_HEAD_P(skb);
1028		if (hh->prim == DL_DATA_REQ) {
1029			/* send packet up */
1030			if (dsp->up) {
1031				if (dsp->up->send(dsp->up, skb))
1032					dev_kfree_skb(skb);
1033			} else
1034				dev_kfree_skb(skb);
1035		} else {
1036			/* send packet down */
1037			if (dsp->ch.peer) {
1038				dsp->data_pending = 1;
1039				if (dsp->ch.recv(dsp->ch.peer, skb)) {
1040					dev_kfree_skb(skb);
1041					dsp->data_pending = 0;
1042				}
1043			} else
1044				dev_kfree_skb(skb);
1045		}
1046	}
1047}
1048
1049static int
1050dspcreate(struct channel_req *crq)
1051{
1052	struct dsp		*ndsp;
1053	u_long		flags;
1054
1055	if (crq->protocol != ISDN_P_B_L2DSP
1056	    && crq->protocol != ISDN_P_B_L2DSPHDLC)
1057		return -EPROTONOSUPPORT;
1058	ndsp = vzalloc(sizeof(struct dsp));
1059	if (!ndsp) {
1060		printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
1061		return -ENOMEM;
1062	}
1063	if (dsp_debug & DEBUG_DSP_CTRL)
1064		printk(KERN_DEBUG "%s: creating new dsp instance\n", __func__);
1065
1066	/* default enabled */
1067	INIT_WORK(&ndsp->workq, (void *)dsp_send_bh);
1068	skb_queue_head_init(&ndsp->sendq);
1069	ndsp->ch.send = dsp_function;
1070	ndsp->ch.ctrl = dsp_ctrl;
1071	ndsp->up = crq->ch;
1072	crq->ch = &ndsp->ch;
1073	if (crq->protocol == ISDN_P_B_L2DSP) {
1074		crq->protocol = ISDN_P_B_RAW;
1075		ndsp->hdlc = 0;
1076	} else {
1077		crq->protocol = ISDN_P_B_HDLC;
1078		ndsp->hdlc = 1;
1079	}
1080	if (!try_module_get(THIS_MODULE))
1081		printk(KERN_WARNING "%s:cannot get module\n",
1082		       __func__);
1083
1084	sprintf(ndsp->name, "DSP_C%x(0x%p)",
1085		ndsp->up->st->dev->id + 1, ndsp);
1086	/* set frame size to start */
1087	ndsp->features.hfc_id = -1; /* current PCM id */
1088	ndsp->features.pcm_id = -1; /* current PCM id */
1089	ndsp->pcm_slot_rx = -1; /* current CPM slot */
1090	ndsp->pcm_slot_tx = -1;
1091	ndsp->pcm_bank_rx = -1;
1092	ndsp->pcm_bank_tx = -1;
1093	ndsp->hfc_conf = -1; /* current conference number */
1094	/* set tone timer */
1095	ndsp->tone.tl.function = (void *)dsp_tone_timeout;
1096	ndsp->tone.tl.data = (long) ndsp;
1097	init_timer(&ndsp->tone.tl);
1098
1099	if (dtmfthreshold < 20 || dtmfthreshold > 500)
1100		dtmfthreshold = 200;
1101	ndsp->dtmf.treshold = dtmfthreshold * 10000;
1102
1103	/* init pipeline append to list */
1104	spin_lock_irqsave(&dsp_lock, flags);
1105	dsp_pipeline_init(&ndsp->pipeline);
1106	list_add_tail(&ndsp->list, &dsp_ilist);
1107	spin_unlock_irqrestore(&dsp_lock, flags);
1108
1109	return 0;
1110}
1111
1112
1113static struct Bprotocol DSP = {
1114	.Bprotocols = (1 << (ISDN_P_B_L2DSP & ISDN_P_B_MASK))
1115	| (1 << (ISDN_P_B_L2DSPHDLC & ISDN_P_B_MASK)),
1116	.name = "dsp",
1117	.create = dspcreate
1118};
1119
1120static int __init dsp_init(void)
1121{
1122	int err;
1123	int tics;
1124
1125	printk(KERN_INFO "DSP module %s\n", mISDN_dsp_revision);
1126
1127	dsp_options = options;
1128	dsp_debug = debug;
1129
1130	/* set packet size */
1131	dsp_poll = poll;
1132	if (dsp_poll) {
1133		if (dsp_poll > MAX_POLL) {
1134			printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
1135			       "maximum.\n", __func__, poll, MAX_POLL);
1136			err = -EINVAL;
1137			return err;
1138		}
1139		if (dsp_poll < 8) {
1140			printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
1141			       "minimum.\n", __func__, dsp_poll);
1142			err = -EINVAL;
1143			return err;
1144		}
1145		dsp_tics = poll * HZ / 8000;
1146		if (dsp_tics * 8000 != poll * HZ) {
1147			printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
1148			       "samples (0,125 ms). It is not a multiple of "
1149			       "%d HZ.\n", poll, HZ);
1150			err = -EINVAL;
1151			return err;
1152		}
1153	} else {
1154		poll = 8;
1155		while (poll <= MAX_POLL) {
1156			tics = (poll * HZ) / 8000;
1157			if (tics * 8000 == poll * HZ) {
1158				dsp_tics = tics;
1159				dsp_poll = poll;
1160				if (poll >= 64)
1161					break;
1162			}
1163			poll++;
1164		}
1165	}
1166	if (dsp_poll == 0) {
1167		printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
1168		       "clock that equals exactly the duration of 8-256 "
1169		       "samples. (Choose kernel clock speed like 100, 250, "
1170		       "300, 1000)\n");
1171		err = -EINVAL;
1172		return err;
1173	}
1174	printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
1175	       "%d jiffies.\n", dsp_poll, dsp_tics);
1176
1177	spin_lock_init(&dsp_lock);
1178	INIT_LIST_HEAD(&dsp_ilist);
1179	INIT_LIST_HEAD(&conf_ilist);
1180
1181	/* init conversion tables */
1182	dsp_audio_generate_law_tables();
1183	dsp_silence = (dsp_options & DSP_OPT_ULAW) ? 0xff : 0x2a;
1184	dsp_audio_law_to_s32 = (dsp_options & DSP_OPT_ULAW) ?
1185		dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
1186	dsp_audio_generate_s2law_table();
1187	dsp_audio_generate_seven();
1188	dsp_audio_generate_mix_table();
1189	if (dsp_options & DSP_OPT_ULAW)
1190		dsp_audio_generate_ulaw_samples();
1191	dsp_audio_generate_volume_changes();
1192
1193	err = dsp_pipeline_module_init();
1194	if (err) {
1195		printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
1196		       "error(%d)\n", err);
1197		return err;
1198	}
1199
1200	err = mISDN_register_Bprotocol(&DSP);
1201	if (err) {
1202		printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
1203		return err;
1204	}
1205
1206	/* set sample timer */
1207	dsp_spl_tl.function = (void *)dsp_cmx_send;
1208	dsp_spl_tl.data = 0;
1209	init_timer(&dsp_spl_tl);
1210	dsp_spl_tl.expires = jiffies + dsp_tics;
1211	dsp_spl_jiffies = dsp_spl_tl.expires;
1212	add_timer(&dsp_spl_tl);
1213
1214	return 0;
1215}
1216
1217
1218static void __exit dsp_cleanup(void)
1219{
1220	mISDN_unregister_Bprotocol(&DSP);
1221
1222	del_timer_sync(&dsp_spl_tl);
1223
1224	if (!list_empty(&dsp_ilist)) {
1225		printk(KERN_ERR "mISDN_dsp: Audio DSP object inst list not "
1226		       "empty.\n");
1227	}
1228	if (!list_empty(&conf_ilist)) {
1229		printk(KERN_ERR "mISDN_dsp: Conference list not empty. Not "
1230		       "all memory freed.\n");
1231	}
1232
1233	dsp_pipeline_module_exit();
1234}
1235
1236module_init(dsp_init);
1237module_exit(dsp_cleanup);
1238