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 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
 165 static const char *mISDN_dsp_revision = "2.0";
 166
 167 static int debug;
 168 static int options;
 169 static int poll;
 170 static int dtmfthreshold = 100;
 171
 172 MODULE_AUTHOR("Andreas Eversberg");
 173 module_param(debug, uint, S_IRUGO | S_IWUSR);
 174 module_param(options, uint, S_IRUGO | S_IWUSR);
 175 module_param(poll, uint, S_IRUGO | S_IWUSR);
 176 module_param(dtmfthreshold, uint, S_IRUGO | S_IWUSR);
 177 MODULE_LICENSE("GPL");
 178
 179 /*int spinnest = 0;*/
 180
 181 spinlock_t dsp_lock; /* global dsp lock */
 182 struct list_head dsp_ilist;
 183 struct list_head conf_ilist;
 184 int dsp_debug;
 185 int dsp_options;
 186 int dsp_poll, dsp_tics;
 187
 188 /* check if rx may be turned off or must be turned on */
 189 static void
 190 dsp_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 }
 236 static void
 237 dsp_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 */
 256 static void
 257 dsp_fill_empty(struct dsp *dsp)
 258 {
 259         struct mISDN_ctrl_req   cq;
 260
 261         memset(&cq, 0, sizeof(cq));
 262
 263         if (!dsp->ch.peer) {
 264                 if (dsp_debug & DEBUG_DSP_CORE)
 265                         printk(KERN_DEBUG "%s: no peer, no fill_empty\n",
 266                                 __func__);
 267                 return;
 268         }
 269         cq.op = MISDN_CTRL_FILL_EMPTY;
 270         cq.p1 = 1;
 271         if (dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq)) {
 272                 printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
 273                         __func__);
 274                 return;
 275         }
 276         if (dsp_debug & DEBUG_DSP_CORE)
 277                 printk(KERN_DEBUG "%s: %s set fill_empty = 1\n",
 278                         __func__, dsp->name);
 279 }
 280
 281 static int
 282 dsp_control_req(struct dsp *dsp, struct mISDNhead *hh, struct sk_buff *skb)
 283 {
 284         struct sk_buff  *nskb;
 285         int ret = 0;
 286         int cont;
 287         u8 *data;
 288         int len;
 289
 290         if (skb->len < sizeof(int))
 291                 printk(KERN_ERR "%s: PH_CONTROL message too short\n", __func__);
 292         cont = *((int *)skb->data);
 293         len = skb->len - sizeof(int);
 294         data = skb->data + sizeof(int);
 295
 296         switch (cont) {
 297         case DTMF_TONE_START: /* turn on DTMF */
 298                 if (dsp->hdlc) {
 299                         ret = -EINVAL;
 300                         break;
 301                 }
 302                 if (dsp_debug & DEBUG_DSP_CORE)
 303                         printk(KERN_DEBUG "%s: start dtmf\n", __func__);
 304                 if (len == sizeof(int)) {
 305                         if (dsp_debug & DEBUG_DSP_CORE)
 306                                 printk(KERN_NOTICE "changing DTMF Threshold "
 307                                         "to %d\n", *((int *)data));
 308                         dsp->dtmf.treshold = (*(int *)data) * 10000;
 309                 }
 310                 dsp->dtmf.enable = 1;
 311                 /* init goertzel */
 312                 dsp_dtmf_goertzel_init(dsp);
 313
 314                 /* check dtmf hardware */
 315                 dsp_dtmf_hardware(dsp);
 316                 dsp_rx_off(dsp);
 317                 break;
 318         case DTMF_TONE_STOP: /* turn off DTMF */
 319                 if (dsp_debug & DEBUG_DSP_CORE)
 320                         printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
 321                 dsp->dtmf.enable = 0;
 322                 dsp->dtmf.hardware = 0;
 323                 dsp->dtmf.software = 0;
 324                 break;
 325         case DSP_CONF_JOIN: /* join / update conference */
 326                 if (len < sizeof(int)) {
 327                         ret = -EINVAL;
 328                         break;
 329                 }
 330                 if (*((u32 *)data) == 0)
 331                         goto conf_split;
 332                 if (dsp_debug & DEBUG_DSP_CORE)
 333                         printk(KERN_DEBUG "%s: join conference %d\n",
 334                                 __func__, *((u32 *)data));
 335                 ret = dsp_cmx_conf(dsp, *((u32 *)data));
 336                         /* dsp_cmx_hardware will also be called here */
 337                 dsp_rx_off(dsp);
 338                 if (dsp_debug & DEBUG_DSP_CMX)
 339                         dsp_cmx_debug(dsp);
 340                 break;
 341         case DSP_CONF_SPLIT: /* remove from conference */
 342 conf_split:
 343                 if (dsp_debug & DEBUG_DSP_CORE)
 344                         printk(KERN_DEBUG "%s: release conference\n", __func__);
 345                 ret = dsp_cmx_conf(dsp, 0);
 346                         /* dsp_cmx_hardware will also be called here */
 347                 if (dsp_debug & DEBUG_DSP_CMX)
 348                         dsp_cmx_debug(dsp);
 349                 dsp_rx_off(dsp);
 350                 break;
 351         case DSP_TONE_PATT_ON: /* play tone */
 352                 if (dsp->hdlc) {
 353                         ret = -EINVAL;
 354                         break;
 355                 }
 356                 if (len < sizeof(int)) {
 357                         ret = -EINVAL;
 358                         break;
 359                 }
 360                 if (dsp_debug & DEBUG_DSP_CORE)
 361                         printk(KERN_DEBUG "%s: turn tone 0x%x on\n",
 362                                 __func__, *((int *)skb->data));
 363                 ret = dsp_tone(dsp, *((int *)data));
 364                 if (!ret) {
 365                         dsp_cmx_hardware(dsp->conf, dsp);
 366                         dsp_rx_off(dsp);
 367                 }
 368                 if (!dsp->tone.tone)
 369                         goto tone_off;
 370                 break;
 371         case DSP_TONE_PATT_OFF: /* stop tone */
 372                 if (dsp->hdlc) {
 373                         ret = -EINVAL;
 374                         break;
 375                 }
 376                 if (dsp_debug & DEBUG_DSP_CORE)
 377                         printk(KERN_DEBUG "%s: turn tone off\n", __func__);
 378                 dsp_tone(dsp, 0);
 379                 dsp_cmx_hardware(dsp->conf, dsp);
 380                 dsp_rx_off(dsp);
 381                 /* reset tx buffers (user space data) */
 382 tone_off:
 383                 dsp->rx_W = 0;
 384                 dsp->rx_R = 0;
 385                 break;
 386         case DSP_VOL_CHANGE_TX: /* change volume */
 387                 if (dsp->hdlc) {
 388                         ret = -EINVAL;
 389                         break;
 390                 }
 391                 if (len < sizeof(int)) {
 392                         ret = -EINVAL;
 393                         break;
 394                 }
 395                 dsp->tx_volume = *((int *)data);
 396                 if (dsp_debug & DEBUG_DSP_CORE)
 397                         printk(KERN_DEBUG "%s: change tx vol to %d\n",
 398                                 __func__, dsp->tx_volume);
 399                 dsp_cmx_hardware(dsp->conf, dsp);
 400                 dsp_dtmf_hardware(dsp);
 401                 dsp_rx_off(dsp);
 402                 break;
 403         case DSP_VOL_CHANGE_RX: /* change volume */
 404                 if (dsp->hdlc) {
 405                         ret = -EINVAL;
 406                         break;
 407                 }
 408                 if (len < sizeof(int)) {
 409                         ret = -EINVAL;
 410                         break;
 411                 }
 412                 dsp->rx_volume = *((int *)data);
 413                 if (dsp_debug & DEBUG_DSP_CORE)
 414                         printk(KERN_DEBUG "%s: change rx vol to %d\n",
 415                                 __func__, dsp->tx_volume);
 416                 dsp_cmx_hardware(dsp->conf, dsp);
 417                 dsp_dtmf_hardware(dsp);
 418                 dsp_rx_off(dsp);
 419                 break;
 420         case DSP_ECHO_ON: /* enable echo */
 421                 dsp->echo.software = 1; /* soft echo */
 422                 if (dsp_debug & DEBUG_DSP_CORE)
 423                         printk(KERN_DEBUG "%s: enable cmx-echo\n", __func__);
 424                 dsp_cmx_hardware(dsp->conf, dsp);
 425                 dsp_rx_off(dsp);
 426                 if (dsp_debug & DEBUG_DSP_CMX)
 427                         dsp_cmx_debug(dsp);
 428                 break;
 429         case DSP_ECHO_OFF: /* disable echo */
 430                 dsp->echo.software = 0;
 431                 dsp->echo.hardware = 0;
 432                 if (dsp_debug & DEBUG_DSP_CORE)
 433                         printk(KERN_DEBUG "%s: disable cmx-echo\n", __func__);
 434                 dsp_cmx_hardware(dsp->conf, dsp);
 435                 dsp_rx_off(dsp);
 436                 if (dsp_debug & DEBUG_DSP_CMX)
 437                         dsp_cmx_debug(dsp);
 438                 break;
 439         case DSP_RECEIVE_ON: /* enable receive to user space */
 440                 if (dsp_debug & DEBUG_DSP_CORE)
 441                         printk(KERN_DEBUG "%s: enable receive to user "
 442                                 "space\n", __func__);
 443                 dsp->rx_disabled = 0;
 444                 dsp_rx_off(dsp);
 445                 break;
 446         case DSP_RECEIVE_OFF: /* disable receive to user space */
 447                 if (dsp_debug & DEBUG_DSP_CORE)
 448                         printk(KERN_DEBUG "%s: disable receive to "
 449                                 "user space\n", __func__);
 450                 dsp->rx_disabled = 1;
 451                 dsp_rx_off(dsp);
 452                 break;
 453         case DSP_MIX_ON: /* enable mixing of tx data */
 454                 if (dsp->hdlc) {
 455                         ret = -EINVAL;
 456                         break;
 457                 }
 458                 if (dsp_debug & DEBUG_DSP_CORE)
 459                         printk(KERN_DEBUG "%s: enable mixing of "
 460                                 "tx-data with conf mebers\n", __func__);
 461                 dsp->tx_mix = 1;
 462                 dsp_cmx_hardware(dsp->conf, dsp);
 463                 dsp_rx_off(dsp);
 464                 if (dsp_debug & DEBUG_DSP_CMX)
 465                         dsp_cmx_debug(dsp);
 466                 break;
 467         case DSP_MIX_OFF: /* disable mixing of tx data */
 468                 if (dsp->hdlc) {
 469                         ret = -EINVAL;
 470                         break;
 471                 }
 472                 if (dsp_debug & DEBUG_DSP_CORE)
 473                         printk(KERN_DEBUG "%s: disable mixing of "
 474                                 "tx-data with conf mebers\n", __func__);
 475                 dsp->tx_mix = 0;
 476                 dsp_cmx_hardware(dsp->conf, dsp);
 477                 dsp_rx_off(dsp);
 478                 if (dsp_debug & DEBUG_DSP_CMX)
 479                         dsp_cmx_debug(dsp);
 480                 break;
 481         case DSP_TXDATA_ON: /* enable txdata */
 482                 dsp->tx_data = 1;
 483                 if (dsp_debug & DEBUG_DSP_CORE)
 484                         printk(KERN_DEBUG "%s: enable tx-data\n", __func__);
 485                 dsp_cmx_hardware(dsp->conf, dsp);
 486                 dsp_rx_off(dsp);
 487                 if (dsp_debug & DEBUG_DSP_CMX)
 488                         dsp_cmx_debug(dsp);
 489                 break;
 490         case DSP_TXDATA_OFF: /* disable txdata */
 491                 dsp->tx_data = 0;
 492                 if (dsp_debug & DEBUG_DSP_CORE)
 493                         printk(KERN_DEBUG "%s: disable tx-data\n", __func__);
 494                 dsp_cmx_hardware(dsp->conf, dsp);
 495                 dsp_rx_off(dsp);
 496                 if (dsp_debug & DEBUG_DSP_CMX)
 497                         dsp_cmx_debug(dsp);
 498                 break;
 499         case DSP_DELAY: /* use delay algorithm instead of dynamic
 500                            jitter algorithm */
 501                 if (dsp->hdlc) {
 502                         ret = -EINVAL;
 503                         break;
 504                 }
 505                 if (len < sizeof(int)) {
 506                         ret = -EINVAL;
 507                         break;
 508                 }
 509                 dsp->cmx_delay = (*((int *)data)) << 3;
 510                         /* milliseconds to samples */
 511                 if (dsp->cmx_delay >= (CMX_BUFF_HALF>>1))
 512                         /* clip to half of maximum usable buffer
 513                         (half of half buffer) */
 514                         dsp->cmx_delay = (CMX_BUFF_HALF>>1) - 1;
 515                 if (dsp_debug & DEBUG_DSP_CORE)
 516                         printk(KERN_DEBUG "%s: use delay algorithm to "
 517                                 "compensate jitter (%d samples)\n",
 518                                 __func__, dsp->cmx_delay);
 519                 break;
 520         case DSP_JITTER: /* use dynamic jitter algorithm instead of
 521                     delay algorithm */
 522                 if (dsp->hdlc) {
 523                         ret = -EINVAL;
 524                         break;
 525                 }
 526                 dsp->cmx_delay = 0;
 527                 if (dsp_debug & DEBUG_DSP_CORE)
 528                         printk(KERN_DEBUG "%s: use jitter algorithm to "
 529                                 "compensate jitter\n", __func__);
 530                 break;
 531         case DSP_TX_DEJITTER: /* use dynamic jitter algorithm for tx-buffer */
 532                 if (dsp->hdlc) {
 533                         ret = -EINVAL;
 534                         break;
 535                 }
 536                 dsp->tx_dejitter = 1;
 537                 if (dsp_debug & DEBUG_DSP_CORE)
 538                         printk(KERN_DEBUG "%s: use dejitter on TX "
 539                                 "buffer\n", __func__);
 540                 break;
 541         case DSP_TX_DEJ_OFF: /* use tx-buffer without dejittering*/
 542                 if (dsp->hdlc) {
 543                         ret = -EINVAL;
 544                         break;
 545                 }
 546                 dsp->tx_dejitter = 0;
 547                 if (dsp_debug & DEBUG_DSP_CORE)
 548                         printk(KERN_DEBUG "%s: use TX buffer without "
 549                                 "dejittering\n", __func__);
 550                 break;
 551         case DSP_PIPELINE_CFG:
 552                 if (dsp->hdlc) {
 553                         ret = -EINVAL;
 554                         break;
 555                 }
 556                 if (len > 0 && ((char *)data)[len - 1]) {
 557                         printk(KERN_DEBUG "%s: pipeline config string "
 558                                 "is not NULL terminated!\n", __func__);
 559                         ret = -EINVAL;
 560                 } else {
 561                         dsp->pipeline.inuse = 1;
 562                         dsp_cmx_hardware(dsp->conf, dsp);
 563                         ret = dsp_pipeline_build(&dsp->pipeline,
 564                                 len > 0 ? data : NULL);
 565                         dsp_cmx_hardware(dsp->conf, dsp);
 566                         dsp_rx_off(dsp);
 567                 }
 568                 break;
 569         case DSP_BF_ENABLE_KEY: /* turn blowfish on */
 570                 if (dsp->hdlc) {
 571                         ret = -EINVAL;
 572                         break;
 573                 }
 574                 if (len < 4 || len > 56) {
 575                         ret = -EINVAL;
 576                         break;
 577                 }
 578                 if (dsp_debug & DEBUG_DSP_CORE)
 579                         printk(KERN_DEBUG "%s: turn blowfish on (key "
 580                                 "not shown)\n", __func__);
 581                 ret = dsp_bf_init(dsp, (u8 *)data, len);
 582                 /* set new cont */
 583                 if (!ret)
 584                         cont = DSP_BF_ACCEPT;
 585                 else
 586                         cont = DSP_BF_REJECT;
 587                 /* send indication if it worked to set it */
 588                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND, MISDN_ID_ANY,
 589                         sizeof(int), &cont, GFP_ATOMIC);
 590                 if (nskb) {
 591                         if (dsp->up) {
 592                                 if (dsp->up->send(dsp->up, nskb))
 593                                         dev_kfree_skb(nskb);
 594                         } else
 595                                 dev_kfree_skb(nskb);
 596                 }
 597                 if (!ret) {
 598                         dsp_cmx_hardware(dsp->conf, dsp);
 599                         dsp_dtmf_hardware(dsp);
 600                         dsp_rx_off(dsp);
 601                 }
 602                 break;
 603         case DSP_BF_DISABLE: /* turn blowfish off */
 604                 if (dsp->hdlc) {
 605                         ret = -EINVAL;
 606                         break;
 607                 }
 608                 if (dsp_debug & DEBUG_DSP_CORE)
 609                         printk(KERN_DEBUG "%s: turn blowfish off\n", __func__);
 610                 dsp_bf_cleanup(dsp);
 611                 dsp_cmx_hardware(dsp->conf, dsp);
 612                 dsp_dtmf_hardware(dsp);
 613                 dsp_rx_off(dsp);
 614                 break;
 615         default:
 616                 if (dsp_debug & DEBUG_DSP_CORE)
 617                         printk(KERN_DEBUG "%s: ctrl req %x unhandled\n",
 618                                 __func__, cont);
 619                 ret = -EINVAL;
 620         }
 621         return ret;
 622 }
 623
 624 static void
 625 get_features(struct mISDNchannel *ch)
 626 {
 627         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 628         struct mISDN_ctrl_req   cq;
 629
 630         if (!ch->peer) {
 631                 if (dsp_debug & DEBUG_DSP_CORE)
 632                         printk(KERN_DEBUG "%s: no peer, no features\n",
 633                                 __func__);
 634                 return;
 635         }
 636         memset(&cq, 0, sizeof(cq));
 637         cq.op = MISDN_CTRL_GETOP;
 638         if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq) < 0) {
 639                 printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
 640                         __func__);
 641                 return;
 642         }
 643         if (cq.op & MISDN_CTRL_RX_OFF)
 644                 dsp->features_rx_off = 1;
 645         if (cq.op & MISDN_CTRL_FILL_EMPTY)
 646                 dsp->features_fill_empty = 1;
 647         if (dsp_options & DSP_OPT_NOHARDWARE)
 648                 return;
 649         if ((cq.op & MISDN_CTRL_HW_FEATURES_OP)) {
 650                 cq.op = MISDN_CTRL_HW_FEATURES;
 651                 *((u_long *)&cq.p1) = (u_long)&dsp->features;
 652                 if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq)) {
 653                         printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
 654                                 __func__);
 655                 }
 656         } else
 657                 if (dsp_debug & DEBUG_DSP_CORE)
 658                         printk(KERN_DEBUG "%s: features not supported for %s\n",
 659                                 __func__, dsp->name);
 660 }
 661
 662 static int
 663 dsp_function(struct mISDNchannel *ch,  struct sk_buff *skb)
 664 {
 665         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 666         struct mISDNhead        *hh;
 667         int                     ret = 0;
 668         u8                      *digits = NULL;
 669         u_long                  flags;
 670
 671         hh = mISDN_HEAD_P(skb);
 672         switch (hh->prim) {
 673         /* FROM DOWN */
 674         case (PH_DATA_CNF):
 675                 dsp->data_pending = 0;
 676                 /* trigger next hdlc frame, if any */
 677                 if (dsp->hdlc) {
 678                         spin_lock_irqsave(&dsp_lock, flags);
 679                         if (dsp->b_active)
 680                                 schedule_work(&dsp->workq);
 681                         spin_unlock_irqrestore(&dsp_lock, flags);
 682                 }
 683                 break;
 684         case (PH_DATA_IND):
 685         case (DL_DATA_IND):
 686                 if (skb->len < 1) {
 687                         ret = -EINVAL;
 688                         break;
 689                 }
 690                 if (dsp->rx_is_off) {
 691                         if (dsp_debug & DEBUG_DSP_CORE)
 692                                 printk(KERN_DEBUG "%s: rx-data during rx_off"
 693                                         " for %s\n",
 694                                 __func__, dsp->name);
 695                 }
 696                 if (dsp->hdlc) {
 697                         /* hdlc */
 698                         spin_lock_irqsave(&dsp_lock, flags);
 699                         dsp_cmx_hdlc(dsp, skb);
 700                         spin_unlock_irqrestore(&dsp_lock, flags);
 701                         if (dsp->rx_disabled) {
 702                                 /* if receive is not allowed */
 703                                 break;
 704                         }
 705                         hh->prim = DL_DATA_IND;
 706                         if (dsp->up)
 707                                 return dsp->up->send(dsp->up, skb);
 708                         break;
 709                 }
 710
 711                 spin_lock_irqsave(&dsp_lock, flags);
 712
 713                 /* decrypt if enabled */
 714                 if (dsp->bf_enable)
 715                         dsp_bf_decrypt(dsp, skb->data, skb->len);
 716                 /* pipeline */
 717                 if (dsp->pipeline.inuse)
 718                         dsp_pipeline_process_rx(&dsp->pipeline, skb->data,
 719                                 skb->len, hh->id);
 720                 /* change volume if requested */
 721                 if (dsp->rx_volume)
 722                         dsp_change_volume(skb, dsp->rx_volume);
 723                 /* check if dtmf soft decoding is turned on */
 724                 if (dsp->dtmf.software) {
 725                         digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
 726                                 skb->len, (dsp_options&DSP_OPT_ULAW) ? 1 : 0);
 727                 }
 728                 /* we need to process receive data if software */
 729                 if (dsp->conf && dsp->conf->software) {
 730                         /* process data from card at cmx */
 731                         dsp_cmx_receive(dsp, skb);
 732                 }
 733
 734                 spin_unlock_irqrestore(&dsp_lock, flags);
 735
 736                 /* send dtmf result, if any */
 737                 if (digits) {
 738                         while (*digits) {
 739                                 int k;
 740                                 struct sk_buff *nskb;
 741                                 if (dsp_debug & DEBUG_DSP_DTMF)
 742                                         printk(KERN_DEBUG "%s: digit"
 743                                             "(%c) to layer %s\n",
 744                                             __func__, *digits, dsp->name);
 745                                 k = *digits | DTMF_TONE_VAL;
 746                                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
 747                                         MISDN_ID_ANY, sizeof(int), &k,
 748                                         GFP_ATOMIC);
 749                                 if (nskb) {
 750                                         if (dsp->up) {
 751                                                 if (dsp->up->send(
 752                                                     dsp->up, nskb))
 753                                                         dev_kfree_skb(nskb);
 754                                         } else
 755                                                 dev_kfree_skb(nskb);
 756                                 }
 757                                 digits++;
 758                         }
 759                 }
 760                 if (dsp->rx_disabled) {
 761                         /* if receive is not allowed */
 762                         break;
 763                 }
 764                 hh->prim = DL_DATA_IND;
 765                 if (dsp->up)
 766                         return dsp->up->send(dsp->up, skb);
 767                 break;
 768         case (PH_CONTROL_IND):
 769                 if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
 770                         printk(KERN_DEBUG "%s: PH_CONTROL INDICATION "
 771                                 "received: %x (len %d) %s\n", __func__,
 772                                 hh->id, skb->len, dsp->name);
 773                 switch (hh->id) {
 774                 case (DTMF_HFC_COEF): /* getting coefficients */
 775                         if (!dsp->dtmf.hardware) {
 776                                 if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
 777                                         printk(KERN_DEBUG "%s: ignoring DTMF "
 778                                                 "coefficients from HFC\n",
 779                                                 __func__);
 780                                 break;
 781                         }
 782                         digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
 783                                 skb->len, 2);
 784                         while (*digits) {
 785                                 int k;
 786                                 struct sk_buff *nskb;
 787                                 if (dsp_debug & DEBUG_DSP_DTMF)
 788                                         printk(KERN_DEBUG "%s: digit"
 789                                             "(%c) to layer %s\n",
 790                                             __func__, *digits, dsp->name);
 791                                 k = *digits | DTMF_TONE_VAL;
 792                                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
 793                                         MISDN_ID_ANY, sizeof(int), &k,
 794                                         GFP_ATOMIC);
 795                                 if (nskb) {
 796                                         if (dsp->up) {
 797                                                 if (dsp->up->send(
 798                                                     dsp->up, nskb))
 799                                                         dev_kfree_skb(nskb);
 800                                         } else
 801                                                 dev_kfree_skb(nskb);
 802                                 }
 803                                 digits++;
 804                         }
 805                         break;
 806                 case (HFC_VOL_CHANGE_TX): /* change volume */
 807                         if (skb->len != sizeof(int)) {
 808                                 ret = -EINVAL;
 809                                 break;
 810                         }
 811                         spin_lock_irqsave(&dsp_lock, flags);
 812                         dsp->tx_volume = *((int *)skb->data);
 813                         if (dsp_debug & DEBUG_DSP_CORE)
 814                                 printk(KERN_DEBUG "%s: change tx volume to "
 815                                         "%d\n", __func__, dsp->tx_volume);
 816                         dsp_cmx_hardware(dsp->conf, dsp);
 817                         dsp_dtmf_hardware(dsp);
 818                         dsp_rx_off(dsp);
 819                         spin_unlock_irqrestore(&dsp_lock, flags);
 820                         break;
 821                 default:
 822                         if (dsp_debug & DEBUG_DSP_CORE)
 823                                 printk(KERN_DEBUG "%s: ctrl ind %x unhandled "
 824                                         "%s\n", __func__, hh->id, dsp->name);
 825                         ret = -EINVAL;
 826                 }
 827                 break;
 828         case (PH_ACTIVATE_IND):
 829         case (PH_ACTIVATE_CNF):
 830                 if (dsp_debug & DEBUG_DSP_CORE)
 831                         printk(KERN_DEBUG "%s: b_channel is now active %s\n",
 832                                 __func__, dsp->name);
 833                 /* bchannel now active */
 834                 spin_lock_irqsave(&dsp_lock, flags);
 835                 dsp->b_active = 1;
 836                 dsp->data_pending = 0;
 837                 dsp->rx_init = 1;
 838                         /* rx_W and rx_R will be adjusted on first frame */
 839                 dsp->rx_W = 0;
 840                 dsp->rx_R = 0;
 841                 memset(dsp->rx_buff, 0, sizeof(dsp->rx_buff));
 842                 dsp_cmx_hardware(dsp->conf, dsp);
 843                 dsp_dtmf_hardware(dsp);
 844                 dsp_rx_off(dsp);
 845                 spin_unlock_irqrestore(&dsp_lock, flags);
 846                 if (dsp_debug & DEBUG_DSP_CORE)
 847                         printk(KERN_DEBUG "%s: done with activation, sending "
 848                                 "confirm to user space. %s\n", __func__,
 849                                 dsp->name);
 850                 /* send activation to upper layer */
 851                 hh->prim = DL_ESTABLISH_CNF;
 852                 if (dsp->up)
 853                         return dsp->up->send(dsp->up, skb);
 854                 break;
 855         case (PH_DEACTIVATE_IND):
 856         case (PH_DEACTIVATE_CNF):
 857                 if (dsp_debug & DEBUG_DSP_CORE)
 858                         printk(KERN_DEBUG "%s: b_channel is now inactive %s\n",
 859                                 __func__, dsp->name);
 860                 /* bchannel now inactive */
 861                 spin_lock_irqsave(&dsp_lock, flags);
 862                 dsp->b_active = 0;
 863                 dsp->data_pending = 0;
 864                 dsp_cmx_hardware(dsp->conf, dsp);
 865                 dsp_rx_off(dsp);
 866                 spin_unlock_irqrestore(&dsp_lock, flags);
 867                 hh->prim = DL_RELEASE_CNF;
 868                 if (dsp->up)
 869                         return dsp->up->send(dsp->up, skb);
 870                 break;
 871         /* FROM UP */
 872         case (DL_DATA_REQ):
 873         case (PH_DATA_REQ):
 874                 if (skb->len < 1) {
 875                         ret = -EINVAL;
 876                         break;
 877                 }
 878                 if (dsp->hdlc) {
 879                         /* hdlc */
 880                         if (!dsp->b_active) {
 881                                 ret = -EIO;
 882                                 break;
 883                         }
 884                         hh->prim = PH_DATA_REQ;
 885                         spin_lock_irqsave(&dsp_lock, flags);
 886                         skb_queue_tail(&dsp->sendq, skb);
 887                         schedule_work(&dsp->workq);
 888                         spin_unlock_irqrestore(&dsp_lock, flags);
 889                         return 0;
 890                 }
 891                 /* send data to tx-buffer (if no tone is played) */
 892                 if (!dsp->tone.tone) {
 893                         spin_lock_irqsave(&dsp_lock, flags);
 894                         dsp_cmx_transmit(dsp, skb);
 895                         spin_unlock_irqrestore(&dsp_lock, flags);
 896                 }
 897                 break;
 898         case (PH_CONTROL_REQ):
 899                 spin_lock_irqsave(&dsp_lock, flags);
 900                 ret = dsp_control_req(dsp, hh, skb);
 901                 spin_unlock_irqrestore(&dsp_lock, flags);
 902                 break;
 903         case (DL_ESTABLISH_REQ):
 904         case (PH_ACTIVATE_REQ):
 905                 if (dsp_debug & DEBUG_DSP_CORE)
 906                         printk(KERN_DEBUG "%s: activating b_channel %s\n",
 907                                 __func__, dsp->name);
 908                 if (dsp->dtmf.hardware || dsp->dtmf.software)
 909                         dsp_dtmf_goertzel_init(dsp);
 910                 get_features(ch);
 911                 /* enable fill_empty feature */
 912                 if (dsp->features_fill_empty)
 913                         dsp_fill_empty(dsp);
 914                 /* send ph_activate */
 915                 hh->prim = PH_ACTIVATE_REQ;
 916                 if (ch->peer)
 917                         return ch->recv(ch->peer, skb);
 918                 break;
 919         case (DL_RELEASE_REQ):
 920         case (PH_DEACTIVATE_REQ):
 921                 if (dsp_debug & DEBUG_DSP_CORE)
 922                         printk(KERN_DEBUG "%s: releasing b_channel %s\n",
 923                                 __func__, dsp->name);
 924                 spin_lock_irqsave(&dsp_lock, flags);
 925                 dsp->tone.tone = 0;
 926                 dsp->tone.hardware = 0;
 927                 dsp->tone.software = 0;
 928                 if (timer_pending(&dsp->tone.tl))
 929                         del_timer(&dsp->tone.tl);
 930                 if (dsp->conf)
 931                         dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be
 932                                                  called here */
 933                 skb_queue_purge(&dsp->sendq);
 934                 spin_unlock_irqrestore(&dsp_lock, flags);
 935                 hh->prim = PH_DEACTIVATE_REQ;
 936                 if (ch->peer)
 937                         return ch->recv(ch->peer, skb);
 938                 break;
 939         default:
 940                 if (dsp_debug & DEBUG_DSP_CORE)
 941                         printk(KERN_DEBUG "%s: msg %x unhandled %s\n",
 942                                 __func__, hh->prim, dsp->name);
 943                 ret = -EINVAL;
 944         }
 945         if (!ret)
 946                 dev_kfree_skb(skb);
 947         return ret;
 948 }
 949
 950 static int
 951 dsp_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
 952 {
 953         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 954         u_long          flags;
 955         int             err = 0;
 956
 957         if (debug & DEBUG_DSP_CTRL)
 958                 printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
 959
 960         switch (cmd) {
 961         case OPEN_CHANNEL:
 962                 break;
 963         case CLOSE_CHANNEL:
 964                 if (dsp->ch.peer)
 965                         dsp->ch.peer->ctrl(dsp->ch.peer, CLOSE_CHANNEL, NULL);
 966
 967                 /* wait until workqueue has finished,
 968                  * must lock here, or we may hit send-process currently
 969                  * queueing. */
 970                 spin_lock_irqsave(&dsp_lock, flags);
 971                 dsp->b_active = 0;
 972                 spin_unlock_irqrestore(&dsp_lock, flags);
 973                 /* MUST not be locked, because it waits until queue is done. */
 974                 cancel_work_sync(&dsp->workq);
 975                 spin_lock_irqsave(&dsp_lock, flags);
 976                 if (timer_pending(&dsp->tone.tl))
 977                         del_timer(&dsp->tone.tl);
 978                 skb_queue_purge(&dsp->sendq);
 979                 if (dsp_debug & DEBUG_DSP_CTRL)
 980                         printk(KERN_DEBUG "%s: releasing member %s\n",
 981                                 __func__, dsp->name);
 982                 dsp->b_active = 0;
 983                 dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be called
 984                                          here */
 985                 dsp_pipeline_destroy(&dsp->pipeline);
 986
 987                 if (dsp_debug & DEBUG_DSP_CTRL)
 988                         printk(KERN_DEBUG "%s: remove & destroy object %s\n",
 989                                 __func__, dsp->name);
 990                 list_del(&dsp->list);
 991                 spin_unlock_irqrestore(&dsp_lock, flags);
 992
 993                 if (dsp_debug & DEBUG_DSP_CTRL)
 994                         printk(KERN_DEBUG "%s: dsp instance released\n",
 995                                 __func__);
 996                 vfree(dsp);
 997                 module_put(THIS_MODULE);
 998                 break;
 999         }
1000         return err;
1001 }
1002
1003 static void
1004 dsp_send_bh(struct work_struct *work)
1005 {
1006         struct dsp *dsp = container_of(work, struct dsp, workq);
1007         struct sk_buff *skb;
1008         struct mISDNhead        *hh;
1009
1010         if (dsp->hdlc && dsp->data_pending)
1011                 return; /* wait until data has been acknowledged */
1012
1013         /* send queued data */
1014         while ((skb = skb_dequeue(&dsp->sendq))) {
1015                 /* in locked date, we must have still data in queue */
1016                 if (dsp->data_pending) {
1017                         if (dsp_debug & DEBUG_DSP_CORE)
1018                                 printk(KERN_DEBUG "%s: fifo full %s, this is "
1019                                         "no bug!\n", __func__, dsp->name);
1020                         /* flush transparent data, if not acked */
1021                         dev_kfree_skb(skb);
1022                         continue;
1023                 }
1024                 hh = mISDN_HEAD_P(skb);
1025                 if (hh->prim == DL_DATA_REQ) {
1026                         /* send packet up */
1027                         if (dsp->up) {
1028                                 if (dsp->up->send(dsp->up, skb))
1029                                         dev_kfree_skb(skb);
1030                         } else
1031                                 dev_kfree_skb(skb);
1032                 } else {
1033                         /* send packet down */
1034                         if (dsp->ch.peer) {
1035                                 dsp->data_pending = 1;
1036                                 if (dsp->ch.recv(dsp->ch.peer, skb)) {
1037                                         dev_kfree_skb(skb);
1038                                         dsp->data_pending = 0;
1039                                 }
1040                         } else
1041                                 dev_kfree_skb(skb);
1042                 }
1043         }
1044 }
1045
1046 static int
1047 dspcreate(struct channel_req *crq)
1048 {
1049         struct dsp              *ndsp;
1050         u_long          flags;
1051
1052         if (crq->protocol != ISDN_P_B_L2DSP
1053          && crq->protocol != ISDN_P_B_L2DSPHDLC)
1054                 return -EPROTONOSUPPORT;
1055         ndsp = vzalloc(sizeof(struct dsp));
1056         if (!ndsp) {
1057                 printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
1058                 return -ENOMEM;
1059         }
1060         if (dsp_debug & DEBUG_DSP_CTRL)
1061                 printk(KERN_DEBUG "%s: creating new dsp instance\n", __func__);
1062
1063         /* default enabled */
1064         INIT_WORK(&ndsp->workq, (void *)dsp_send_bh);
1065         skb_queue_head_init(&ndsp->sendq);
1066         ndsp->ch.send = dsp_function;
1067         ndsp->ch.ctrl = dsp_ctrl;
1068         ndsp->up = crq->ch;
1069         crq->ch = &ndsp->ch;
1070         if (crq->protocol == ISDN_P_B_L2DSP) {
1071                 crq->protocol = ISDN_P_B_RAW;
1072                 ndsp->hdlc = 0;
1073         } else {
1074                 crq->protocol = ISDN_P_B_HDLC;
1075                 ndsp->hdlc = 1;
1076         }
1077         if (!try_module_get(THIS_MODULE))
1078                 printk(KERN_WARNING "%s:cannot get module\n",
1079                         __func__);
1080
1081         sprintf(ndsp->name, "DSP_C%x(0x%p)",
1082                 ndsp->up->st->dev->id + 1, ndsp);
1083         /* set frame size to start */
1084         ndsp->features.hfc_id = -1; /* current PCM id */
1085         ndsp->features.pcm_id = -1; /* current PCM id */
1086         ndsp->pcm_slot_rx = -1; /* current CPM slot */
1087         ndsp->pcm_slot_tx = -1;
1088         ndsp->pcm_bank_rx = -1;
1089         ndsp->pcm_bank_tx = -1;
1090         ndsp->hfc_conf = -1; /* current conference number */
1091         /* set tone timer */
1092         ndsp->tone.tl.function = (void *)dsp_tone_timeout;
1093         ndsp->tone.tl.data = (long) ndsp;
1094         init_timer(&ndsp->tone.tl);
1095
1096         if (dtmfthreshold < 20 || dtmfthreshold > 500)
1097                 dtmfthreshold = 200;
1098         ndsp->dtmf.treshold = dtmfthreshold*10000;
1099
1100         /* init pipeline append to list */
1101         spin_lock_irqsave(&dsp_lock, flags);
1102         dsp_pipeline_init(&ndsp->pipeline);
1103         list_add_tail(&ndsp->list, &dsp_ilist);
1104         spin_unlock_irqrestore(&dsp_lock, flags);
1105
1106         return 0;
1107 }
1108
1109
1110 static struct Bprotocol DSP = {
1111         .Bprotocols = (1 << (ISDN_P_B_L2DSP & ISDN_P_B_MASK))
1112                 | (1 << (ISDN_P_B_L2DSPHDLC & ISDN_P_B_MASK)),
1113         .name = "dsp",
1114         .create = dspcreate
1115 };
1116
1117 static int __init dsp_init(void)
1118 {
1119         int err;
1120         int tics;
1121
1122         printk(KERN_INFO "DSP modul %s\n", mISDN_dsp_revision);
1123
1124         dsp_options = options;
1125         dsp_debug = debug;
1126
1127         /* set packet size */
1128         dsp_poll = poll;
1129         if (dsp_poll) {
1130                 if (dsp_poll > MAX_POLL) {
1131                         printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
1132                                 "maximum.\n", __func__, poll, MAX_POLL);
1133                         err = -EINVAL;
1134                         return err;
1135                 }
1136                 if (dsp_poll < 8) {
1137                         printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
1138                                 "minimum.\n", __func__, dsp_poll);
1139                         err = -EINVAL;
1140                         return err;
1141                 }
1142                 dsp_tics = poll * HZ / 8000;
1143                 if (dsp_tics * 8000 != poll * HZ) {
1144                         printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
1145                                 "samples (0,125 ms). It is not a multiple of "
1146                                 "%d HZ.\n", poll, HZ);
1147                         err = -EINVAL;
1148                         return err;
1149                 }
1150         } else {
1151                 poll = 8;
1152                 while (poll <= MAX_POLL) {
1153                         tics = (poll * HZ) / 8000;
1154                         if (tics * 8000 == poll * HZ) {
1155                                 dsp_tics = tics;
1156                                 dsp_poll = poll;
1157                                 if (poll >= 64)
1158                                         break;
1159                         }
1160                         poll++;
1161                 }
1162         }
1163         if (dsp_poll == 0) {
1164                 printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
1165                         "clock that equals exactly the duration of 8-256 "
1166                         "samples. (Choose kernel clock speed like 100, 250, "
1167                         "300, 1000)\n");
1168                 err = -EINVAL;
1169                 return err;
1170         }
1171         printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
1172                 "%d jiffies.\n", dsp_poll, dsp_tics);
1173
1174         spin_lock_init(&dsp_lock);
1175         INIT_LIST_HEAD(&dsp_ilist);
1176         INIT_LIST_HEAD(&conf_ilist);
1177
1178         /* init conversion tables */
1179         dsp_audio_generate_law_tables();
1180         dsp_silence = (dsp_options&DSP_OPT_ULAW) ? 0xff : 0x2a;
1181         dsp_audio_law_to_s32 = (dsp_options&DSP_OPT_ULAW) ?
1182                 dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
1183         dsp_audio_generate_s2law_table();
1184         dsp_audio_generate_seven();
1185         dsp_audio_generate_mix_table();
1186         if (dsp_options & DSP_OPT_ULAW)
1187                 dsp_audio_generate_ulaw_samples();
1188         dsp_audio_generate_volume_changes();
1189
1190         err = dsp_pipeline_module_init();
1191         if (err) {
1192                 printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
1193                         "error(%d)\n", err);
1194                 return err;
1195         }
1196
1197         err = mISDN_register_Bprotocol(&DSP);
1198         if (err) {
1199                 printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
1200                 return err;
1201         }
1202
1203         /* set sample timer */
1204         dsp_spl_tl.function = (void *)dsp_cmx_send;
1205         dsp_spl_tl.data = 0;
1206         init_timer(&dsp_spl_tl);
1207         dsp_spl_tl.expires = jiffies + dsp_tics;
1208         dsp_spl_jiffies = dsp_spl_tl.expires;
1209         add_timer(&dsp_spl_tl);
1210
1211         return 0;
1212 }
1213
1214
1215 static void __exit dsp_cleanup(void)
1216 {
1217         mISDN_unregister_Bprotocol(&DSP);
1218
1219         if (timer_pending(&dsp_spl_tl))
1220                 del_timer(&dsp_spl_tl);
1221
1222         if (!list_empty(&dsp_ilist)) {
1223                 printk(KERN_ERR "mISDN_dsp: Audio DSP object inst list not "
1224                         "empty.\n");
1225         }
1226         if (!list_empty(&conf_ilist)) {
1227                 printk(KERN_ERR "mISDN_dsp: Conference list not empty. Not "
1228                         "all memory freed.\n");
1229         }
1230
1231         dsp_pipeline_module_exit();
1232 }
1233
1234 module_init(dsp_init);
1235 module_exit(dsp_cleanup);
1236