drivers/isdn/mISDN/dsp_core.c

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