drivers/isdn/mISDN/dsp_core.c

   1 /*
   2  * Author       Andreas Eversberg ([email protected])
   3  * Based on source code structure by
   4  *              Karsten Keil ([email protected])
   5  *
   6  *              This file is (c) under GNU PUBLIC LICENSE
   7  *
   8  * Thanks to    Karsten Keil (great drivers)
   9  *              Cologne Chip (great chips)
  10  *
  11  * This module does:
  12  *              Real-time tone generation
  13  *              DTMF detection
  14  *              Real-time cross-connection and conferrence
  15  *              Compensate jitter due to system load and hardware fault.
  16  *              All features are done in kernel space and will be realized
  17  *              using hardware, if available and supported by chip set.
  18  *              Blowfish encryption/decryption
  19  */
  20
  21 /* STRUCTURE:
  22  *
  23  * The dsp module provides layer 2 for b-channels (64kbit). It provides
  24  * transparent audio forwarding with special digital signal processing:
  25  *
  26  * - (1) generation of tones
  27  * - (2) detection of dtmf tones
  28  * - (3) crossconnecting and conferences (clocking)
  29  * - (4) echo generation for delay test
  30  * - (5) volume control
  31  * - (6) disable receive data
  32  * - (7) pipeline
  33  * - (8) encryption/decryption
  34  *
  35  * Look:
  36  *             TX            RX
  37  *         ------upper layer------
  38  *             |             ^
  39  *             |             |(6)
  40  *             v             |
  41  *       +-----+-------------+-----+
  42  *       |(3)(4)                   |
  43  *       |           CMX           |
  44  *       |                         |
  45  *       |           +-------------+
  46  *       |           |       ^
  47  *       |           |       |
  48  *       |+---------+|  +----+----+
  49  *       ||(1)      ||  |(2)      |
  50  *       ||         ||  |         |
  51  *       ||  Tones  ||  |  DTMF   |
  52  *       ||         ||  |         |
  53  *       ||         ||  |         |
  54  *       |+----+----+|  +----+----+
  55  *       +-----+-----+       ^
  56  *             |             |
  57  *             v             |
  58  *        +----+----+   +----+----+
  59  *        |(5)      |   |(5)      |
  60  *        |         |   |         |
  61  *        |TX Volume|   |RX Volume|
  62  *        |         |   |         |
  63  *        |         |   |         |
  64  *        +----+----+   +----+----+
  65  *             |             ^
  66  *             |             |
  67  *             v             |
  68  *        +----+-------------+----+
  69  *        |(7)                    |
  70  *        |                       |
  71  *        |  Pipeline Processing  |
  72  *        |                       |
  73  *        |                       |
  74  *        +----+-------------+----+
  75  *             |             ^
  76  *             |             |
  77  *             v             |
  78  *        +----+----+   +----+----+
  79  *        |(8)      |   |(8)      |
  80  *        |         |   |         |
  81  *        | Encrypt |   | Decrypt |
  82  *        |         |   |         |
  83  *        |         |   |         |
  84  *        +----+----+   +----+----+
  85  *             |             ^
  86  *             |             |
  87  *             v             |
  88  *         ------card  layer------
  89  *             TX            RX
  90  *
  91  * Above you can see the logical data flow. If software is used to do the
  92  * process, it is actually the real data flow. If hardware is used, data
  93  * may not flow, but hardware commands to the card, to provide the data flow
  94  * as shown.
  95  *
  96  * NOTE: The channel must be activated in order to make dsp work, even if
  97  * no data flow to the upper layer is intended. Activation can be done
  98  * after and before controlling the setting using PH_CONTROL requests.
  99  *
 100  * DTMF: Will be detected by hardware if possible. It is done before CMX
 101  * processing.
 102  *
 103  * Tones: Will be generated via software if endless looped audio fifos are
 104  * not supported by hardware. Tones will override all data from CMX.
 105  * It is not required to join a conference to use tones at any time.
 106  *
 107  * CMX: Is transparent when not used. When it is used, it will do
 108  * crossconnections and conferences via software if not possible through
 109  * hardware. If hardware capability is available, hardware is used.
 110  *
 111  * Echo: Is generated by CMX and is used to check performance of hard and
 112  * software CMX.
 113  *
 114  * The CMX has special functions for conferences with one, two and more
 115  * members. It will allow different types of data flow. Receive and transmit
 116  * data to/form upper layer may be switched on/off individually without losing
 117  * features of CMX, Tones and DTMF.
 118  *
 119  * Echo Cancellation: Sometimes we like to cancel echo from the interface.
 120  * Note that a VoIP call may not have echo caused by the IP phone. The echo
 121  * is generated by the telephone line connected to it. Because the delay
 122  * is high, it becomes an echo. RESULT: Echo Cachelation is required if
 123  * both echo AND delay is applied to an interface.
 124  * Remember that software CMX always generates a more or less delay.
 125  *
 126  * If all used features can be realized in hardware, and if transmit and/or
 127  * receive data ist disabled, the card may not send/receive any data at all.
 128  * Not receiving is useful if only announcements are played. Not sending is
 129  * useful if an answering machine records audio. Not sending and receiving is
 130  * useful during most states of the call. If supported by hardware, tones
 131  * will be played without cpu load. Small PBXs and NT-Mode applications will
 132  * not need expensive hardware when processing calls.
 133  *
 134  *
 135  * LOCKING:
 136  *
 137  * When data is received from upper or lower layer (card), the complete dsp
 138  * module is locked by a global lock.  This lock MUST lock irq, because it
 139  * must lock timer events by DSP poll timer.
 140  * When data is ready to be transmitted down, the data is queued and sent
 141  * outside lock and timer event.
 142  * PH_CONTROL must not change any settings, join or split conference members
 143  * during process of data.
 144  *
 145  * HDLC:
 146  *
 147  * It works quite the same as transparent, except that HDLC data is forwarded
 148  * to all other conference members if no hardware bridging is possible.
 149  * Send data will be writte to sendq. Sendq will be sent if confirm is received.
 150  * Conference cannot join, if one member is not hdlc.
 151  *
 152  */
 153
 154 #include <linux/delay.h>
 155 #include <linux/gfp.h>
 156 #include <linux/mISDNif.h>
 157 #include <linux/mISDNdsp.h>
 158 #include <linux/module.h>
 159 #include <linux/vmalloc.h>
 160 #include "core.h"
 161 #include "dsp.h"
 162
 163 static const char *mISDN_dsp_revision = "2.0";
 164
 165 static int debug;
 166 static int options;
 167 static int poll;
 168 static int dtmfthreshold = 100;
 169
 170 MODULE_AUTHOR("Andreas Eversberg");
 171 module_param(debug, uint, S_IRUGO | S_IWUSR);
 172 module_param(options, uint, S_IRUGO | S_IWUSR);
 173 module_param(poll, uint, S_IRUGO | S_IWUSR);
 174 module_param(dtmfthreshold, uint, S_IRUGO | S_IWUSR);
 175 MODULE_DESCRIPTION("mISDN driver for Digital Audio Processing of transparent data");
 176 MODULE_LICENSE("GPL");
 177
 178 /*int spinnest = 0;*/
 179
 180 DEFINE_SPINLOCK(dsp_lock); /* global dsp lock */
 181 LIST_HEAD(dsp_ilist);
 182 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         cq.p2 = dsp_silence;
 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                 return -EINVAL;
 293         }
 294         cont = *((int *)skb->data);
 295         len = skb->len - sizeof(int);
 296         data = skb->data + sizeof(int);
 297
 298         switch (cont) {
 299         case DTMF_TONE_START: /* turn on DTMF */
 300                 if (dsp->hdlc) {
 301                         ret = -EINVAL;
 302                         break;
 303                 }
 304                 if (dsp_debug & DEBUG_DSP_CORE)
 305                         printk(KERN_DEBUG "%s: start dtmf\n", __func__);
 306                 if (len == sizeof(int)) {
 307                         if (dsp_debug & DEBUG_DSP_CORE)
 308                                 printk(KERN_NOTICE "changing DTMF Threshold "
 309                                        "to %d\n", *((int *)data));
 310                         dsp->dtmf.treshold = (*(int *)data) * 10000;
 311                 }
 312                 dsp->dtmf.enable = 1;
 313                 /* init goertzel */
 314                 dsp_dtmf_goertzel_init(dsp);
 315
 316                 /* check dtmf hardware */
 317                 dsp_dtmf_hardware(dsp);
 318                 dsp_rx_off(dsp);
 319                 break;
 320         case DTMF_TONE_STOP: /* turn off DTMF */
 321                 if (dsp_debug & DEBUG_DSP_CORE)
 322                         printk(KERN_DEBUG "%s: stop dtmf\n", __func__);
 323                 dsp->dtmf.enable = 0;
 324                 dsp->dtmf.hardware = 0;
 325                 dsp->dtmf.software = 0;
 326                 break;
 327         case DSP_CONF_JOIN: /* join / update conference */
 328                 if (len < sizeof(int)) {
 329                         ret = -EINVAL;
 330                         break;
 331                 }
 332                 if (*((u32 *)data) == 0)
 333                         goto conf_split;
 334                 if (dsp_debug & DEBUG_DSP_CORE)
 335                         printk(KERN_DEBUG "%s: join conference %d\n",
 336                                __func__, *((u32 *)data));
 337                 ret = dsp_cmx_conf(dsp, *((u32 *)data));
 338                 /* dsp_cmx_hardware will also be called here */
 339                 dsp_rx_off(dsp);
 340                 if (dsp_debug & DEBUG_DSP_CMX)
 341                         dsp_cmx_debug(dsp);
 342                 break;
 343         case DSP_CONF_SPLIT: /* remove from conference */
 344         conf_split:
 345                 if (dsp_debug & DEBUG_DSP_CORE)
 346                         printk(KERN_DEBUG "%s: release conference\n", __func__);
 347                 ret = dsp_cmx_conf(dsp, 0);
 348                 /* dsp_cmx_hardware will also be called here */
 349                 if (dsp_debug & DEBUG_DSP_CMX)
 350                         dsp_cmx_debug(dsp);
 351                 dsp_rx_off(dsp);
 352                 break;
 353         case DSP_TONE_PATT_ON: /* play tone */
 354                 if (dsp->hdlc) {
 355                         ret = -EINVAL;
 356                         break;
 357                 }
 358                 if (len < sizeof(int)) {
 359                         ret = -EINVAL;
 360                         break;
 361                 }
 362                 if (dsp_debug & DEBUG_DSP_CORE)
 363                         printk(KERN_DEBUG "%s: turn tone 0x%x on\n",
 364                                __func__, *((int *)skb->data));
 365                 ret = dsp_tone(dsp, *((int *)data));
 366                 if (!ret) {
 367                         dsp_cmx_hardware(dsp->conf, dsp);
 368                         dsp_rx_off(dsp);
 369                 }
 370                 if (!dsp->tone.tone)
 371                         goto tone_off;
 372                 break;
 373         case DSP_TONE_PATT_OFF: /* stop tone */
 374                 if (dsp->hdlc) {
 375                         ret = -EINVAL;
 376                         break;
 377                 }
 378                 if (dsp_debug & DEBUG_DSP_CORE)
 379                         printk(KERN_DEBUG "%s: turn tone off\n", __func__);
 380                 dsp_tone(dsp, 0);
 381                 dsp_cmx_hardware(dsp->conf, dsp);
 382                 dsp_rx_off(dsp);
 383                 /* reset tx buffers (user space data) */
 384         tone_off:
 385                 dsp->rx_W = 0;
 386                 dsp->rx_R = 0;
 387                 break;
 388         case DSP_VOL_CHANGE_TX: /* change volume */
 389                 if (dsp->hdlc) {
 390                         ret = -EINVAL;
 391                         break;
 392                 }
 393                 if (len < sizeof(int)) {
 394                         ret = -EINVAL;
 395                         break;
 396                 }
 397                 dsp->tx_volume = *((int *)data);
 398                 if (dsp_debug & DEBUG_DSP_CORE)
 399                         printk(KERN_DEBUG "%s: change tx vol to %d\n",
 400                                __func__, dsp->tx_volume);
 401                 dsp_cmx_hardware(dsp->conf, dsp);
 402                 dsp_dtmf_hardware(dsp);
 403                 dsp_rx_off(dsp);
 404                 break;
 405         case DSP_VOL_CHANGE_RX: /* change volume */
 406                 if (dsp->hdlc) {
 407                         ret = -EINVAL;
 408                         break;
 409                 }
 410                 if (len < sizeof(int)) {
 411                         ret = -EINVAL;
 412                         break;
 413                 }
 414                 dsp->rx_volume = *((int *)data);
 415                 if (dsp_debug & DEBUG_DSP_CORE)
 416                         printk(KERN_DEBUG "%s: change rx vol to %d\n",
 417                                __func__, dsp->tx_volume);
 418                 dsp_cmx_hardware(dsp->conf, dsp);
 419                 dsp_dtmf_hardware(dsp);
 420                 dsp_rx_off(dsp);
 421                 break;
 422         case DSP_ECHO_ON: /* enable echo */
 423                 dsp->echo.software = 1; /* soft echo */
 424                 if (dsp_debug & DEBUG_DSP_CORE)
 425                         printk(KERN_DEBUG "%s: enable cmx-echo\n", __func__);
 426                 dsp_cmx_hardware(dsp->conf, dsp);
 427                 dsp_rx_off(dsp);
 428                 if (dsp_debug & DEBUG_DSP_CMX)
 429                         dsp_cmx_debug(dsp);
 430                 break;
 431         case DSP_ECHO_OFF: /* disable echo */
 432                 dsp->echo.software = 0;
 433                 dsp->echo.hardware = 0;
 434                 if (dsp_debug & DEBUG_DSP_CORE)
 435                         printk(KERN_DEBUG "%s: disable cmx-echo\n", __func__);
 436                 dsp_cmx_hardware(dsp->conf, dsp);
 437                 dsp_rx_off(dsp);
 438                 if (dsp_debug & DEBUG_DSP_CMX)
 439                         dsp_cmx_debug(dsp);
 440                 break;
 441         case DSP_RECEIVE_ON: /* enable receive to user space */
 442                 if (dsp_debug & DEBUG_DSP_CORE)
 443                         printk(KERN_DEBUG "%s: enable receive to user "
 444                                "space\n", __func__);
 445                 dsp->rx_disabled = 0;
 446                 dsp_rx_off(dsp);
 447                 break;
 448         case DSP_RECEIVE_OFF: /* disable receive to user space */
 449                 if (dsp_debug & DEBUG_DSP_CORE)
 450                         printk(KERN_DEBUG "%s: disable receive to "
 451                                "user space\n", __func__);
 452                 dsp->rx_disabled = 1;
 453                 dsp_rx_off(dsp);
 454                 break;
 455         case DSP_MIX_ON: /* enable mixing of tx data */
 456                 if (dsp->hdlc) {
 457                         ret = -EINVAL;
 458                         break;
 459                 }
 460                 if (dsp_debug & DEBUG_DSP_CORE)
 461                         printk(KERN_DEBUG "%s: enable mixing of "
 462                                "tx-data with conf members\n", __func__);
 463                 dsp->tx_mix = 1;
 464                 dsp_cmx_hardware(dsp->conf, dsp);
 465                 dsp_rx_off(dsp);
 466                 if (dsp_debug & DEBUG_DSP_CMX)
 467                         dsp_cmx_debug(dsp);
 468                 break;
 469         case DSP_MIX_OFF: /* disable mixing of tx data */
 470                 if (dsp->hdlc) {
 471                         ret = -EINVAL;
 472                         break;
 473                 }
 474                 if (dsp_debug & DEBUG_DSP_CORE)
 475                         printk(KERN_DEBUG "%s: disable mixing of "
 476                                "tx-data with conf members\n", __func__);
 477                 dsp->tx_mix = 0;
 478                 dsp_cmx_hardware(dsp->conf, dsp);
 479                 dsp_rx_off(dsp);
 480                 if (dsp_debug & DEBUG_DSP_CMX)
 481                         dsp_cmx_debug(dsp);
 482                 break;
 483         case DSP_TXDATA_ON: /* enable txdata */
 484                 dsp->tx_data = 1;
 485                 if (dsp_debug & DEBUG_DSP_CORE)
 486                         printk(KERN_DEBUG "%s: enable tx-data\n", __func__);
 487                 dsp_cmx_hardware(dsp->conf, dsp);
 488                 dsp_rx_off(dsp);
 489                 if (dsp_debug & DEBUG_DSP_CMX)
 490                         dsp_cmx_debug(dsp);
 491                 break;
 492         case DSP_TXDATA_OFF: /* disable txdata */
 493                 dsp->tx_data = 0;
 494                 if (dsp_debug & DEBUG_DSP_CORE)
 495                         printk(KERN_DEBUG "%s: disable tx-data\n", __func__);
 496                 dsp_cmx_hardware(dsp->conf, dsp);
 497                 dsp_rx_off(dsp);
 498                 if (dsp_debug & DEBUG_DSP_CMX)
 499                         dsp_cmx_debug(dsp);
 500                 break;
 501         case DSP_DELAY: /* use delay algorithm instead of dynamic
 502                            jitter algorithm */
 503                 if (dsp->hdlc) {
 504                         ret = -EINVAL;
 505                         break;
 506                 }
 507                 if (len < sizeof(int)) {
 508                         ret = -EINVAL;
 509                         break;
 510                 }
 511                 dsp->cmx_delay = (*((int *)data)) << 3;
 512                 /* milliseconds to samples */
 513                 if (dsp->cmx_delay >= (CMX_BUFF_HALF >> 1))
 514                         /* clip to half of maximum usable buffer
 515                            (half of half buffer) */
 516                         dsp->cmx_delay = (CMX_BUFF_HALF >> 1) - 1;
 517                 if (dsp_debug & DEBUG_DSP_CORE)
 518                         printk(KERN_DEBUG "%s: use delay algorithm to "
 519                                "compensate jitter (%d samples)\n",
 520                                __func__, dsp->cmx_delay);
 521                 break;
 522         case DSP_JITTER: /* use dynamic jitter algorithm instead of
 523                             delay algorithm */
 524                 if (dsp->hdlc) {
 525                         ret = -EINVAL;
 526                         break;
 527                 }
 528                 dsp->cmx_delay = 0;
 529                 if (dsp_debug & DEBUG_DSP_CORE)
 530                         printk(KERN_DEBUG "%s: use jitter algorithm to "
 531                                "compensate jitter\n", __func__);
 532                 break;
 533         case DSP_TX_DEJITTER: /* use dynamic jitter algorithm for tx-buffer */
 534                 if (dsp->hdlc) {
 535                         ret = -EINVAL;
 536                         break;
 537                 }
 538                 dsp->tx_dejitter = 1;
 539                 if (dsp_debug & DEBUG_DSP_CORE)
 540                         printk(KERN_DEBUG "%s: use dejitter on TX "
 541                                "buffer\n", __func__);
 542                 break;
 543         case DSP_TX_DEJ_OFF: /* use tx-buffer without dejittering*/
 544                 if (dsp->hdlc) {
 545                         ret = -EINVAL;
 546                         break;
 547                 }
 548                 dsp->tx_dejitter = 0;
 549                 if (dsp_debug & DEBUG_DSP_CORE)
 550                         printk(KERN_DEBUG "%s: use TX buffer without "
 551                                "dejittering\n", __func__);
 552                 break;
 553         case DSP_PIPELINE_CFG:
 554                 if (dsp->hdlc) {
 555                         ret = -EINVAL;
 556                         break;
 557                 }
 558                 if (len > 0 && ((char *)data)[len - 1]) {
 559                         printk(KERN_DEBUG "%s: pipeline config string "
 560                                "is not NULL terminated!\n", __func__);
 561                         ret = -EINVAL;
 562                 } else {
 563                         dsp->pipeline.inuse = 1;
 564                         dsp_cmx_hardware(dsp->conf, dsp);
 565                         ret = dsp_pipeline_build(&dsp->pipeline,
 566                                                  len > 0 ? data : NULL);
 567                         dsp_cmx_hardware(dsp->conf, dsp);
 568                         dsp_rx_off(dsp);
 569                 }
 570                 break;
 571         case DSP_BF_ENABLE_KEY: /* turn blowfish on */
 572                 if (dsp->hdlc) {
 573                         ret = -EINVAL;
 574                         break;
 575                 }
 576                 if (len < 4 || len > 56) {
 577                         ret = -EINVAL;
 578                         break;
 579                 }
 580                 if (dsp_debug & DEBUG_DSP_CORE)
 581                         printk(KERN_DEBUG "%s: turn blowfish on (key "
 582                                "not shown)\n", __func__);
 583                 ret = dsp_bf_init(dsp, (u8 *)data, len);
 584                 /* set new cont */
 585                 if (!ret)
 586                         cont = DSP_BF_ACCEPT;
 587                 else
 588                         cont = DSP_BF_REJECT;
 589                 /* send indication if it worked to set it */
 590                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND, MISDN_ID_ANY,
 591                                         sizeof(int), &cont, GFP_ATOMIC);
 592                 if (nskb) {
 593                         if (dsp->up) {
 594                                 if (dsp->up->send(dsp->up, nskb))
 595                                         dev_kfree_skb(nskb);
 596                         } else
 597                                 dev_kfree_skb(nskb);
 598                 }
 599                 if (!ret) {
 600                         dsp_cmx_hardware(dsp->conf, dsp);
 601                         dsp_dtmf_hardware(dsp);
 602                         dsp_rx_off(dsp);
 603                 }
 604                 break;
 605         case DSP_BF_DISABLE: /* turn blowfish off */
 606                 if (dsp->hdlc) {
 607                         ret = -EINVAL;
 608                         break;
 609                 }
 610                 if (dsp_debug & DEBUG_DSP_CORE)
 611                         printk(KERN_DEBUG "%s: turn blowfish off\n", __func__);
 612                 dsp_bf_cleanup(dsp);
 613                 dsp_cmx_hardware(dsp->conf, dsp);
 614                 dsp_dtmf_hardware(dsp);
 615                 dsp_rx_off(dsp);
 616                 break;
 617         default:
 618                 if (dsp_debug & DEBUG_DSP_CORE)
 619                         printk(KERN_DEBUG "%s: ctrl req %x unhandled\n",
 620                                __func__, cont);
 621                 ret = -EINVAL;
 622         }
 623         return ret;
 624 }
 625
 626 static void
 627 get_features(struct mISDNchannel *ch)
 628 {
 629         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 630         struct mISDN_ctrl_req   cq;
 631
 632         if (!ch->peer) {
 633                 if (dsp_debug & DEBUG_DSP_CORE)
 634                         printk(KERN_DEBUG "%s: no peer, no features\n",
 635                                __func__);
 636                 return;
 637         }
 638         memset(&cq, 0, sizeof(cq));
 639         cq.op = MISDN_CTRL_GETOP;
 640         if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq) < 0) {
 641                 printk(KERN_DEBUG "%s: CONTROL_CHANNEL failed\n",
 642                        __func__);
 643                 return;
 644         }
 645         if (cq.op & MISDN_CTRL_RX_OFF)
 646                 dsp->features_rx_off = 1;
 647         if (cq.op & MISDN_CTRL_FILL_EMPTY)
 648                 dsp->features_fill_empty = 1;
 649         if (dsp_options & DSP_OPT_NOHARDWARE)
 650                 return;
 651         if ((cq.op & MISDN_CTRL_HW_FEATURES_OP)) {
 652                 cq.op = MISDN_CTRL_HW_FEATURES;
 653                 *((u_long *)&cq.p1) = (u_long)&dsp->features;
 654                 if (ch->peer->ctrl(ch->peer, CONTROL_CHANNEL, &cq)) {
 655                         printk(KERN_DEBUG "%s: 2nd CONTROL_CHANNEL failed\n",
 656                                __func__);
 657                 }
 658         } else
 659                 if (dsp_debug & DEBUG_DSP_CORE)
 660                         printk(KERN_DEBUG "%s: features not supported for %s\n",
 661                                __func__, dsp->name);
 662 }
 663
 664 static int
 665 dsp_function(struct mISDNchannel *ch,  struct sk_buff *skb)
 666 {
 667         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 668         struct mISDNhead        *hh;
 669         int                     ret = 0;
 670         u8                      *digits = NULL;
 671         u_long                  flags;
 672
 673         hh = mISDN_HEAD_P(skb);
 674         switch (hh->prim) {
 675                 /* FROM DOWN */
 676         case (PH_DATA_CNF):
 677                 dsp->data_pending = 0;
 678                 /* trigger next hdlc frame, if any */
 679                 if (dsp->hdlc) {
 680                         spin_lock_irqsave(&dsp_lock, flags);
 681                         if (dsp->b_active)
 682                                 schedule_work(&dsp->workq);
 683                         spin_unlock_irqrestore(&dsp_lock, flags);
 684                 }
 685                 break;
 686         case (PH_DATA_IND):
 687         case (DL_DATA_IND):
 688                 if (skb->len < 1) {
 689                         ret = -EINVAL;
 690                         break;
 691                 }
 692                 if (dsp->rx_is_off) {
 693                         if (dsp_debug & DEBUG_DSP_CORE)
 694                                 printk(KERN_DEBUG "%s: rx-data during rx_off"
 695                                        " for %s\n",
 696                                        __func__, dsp->name);
 697                 }
 698                 if (dsp->hdlc) {
 699                         /* hdlc */
 700                         spin_lock_irqsave(&dsp_lock, flags);
 701                         dsp_cmx_hdlc(dsp, skb);
 702                         spin_unlock_irqrestore(&dsp_lock, flags);
 703                         if (dsp->rx_disabled) {
 704                                 /* if receive is not allowed */
 705                                 break;
 706                         }
 707                         hh->prim = DL_DATA_IND;
 708                         if (dsp->up)
 709                                 return dsp->up->send(dsp->up, skb);
 710                         break;
 711                 }
 712
 713                 spin_lock_irqsave(&dsp_lock, flags);
 714
 715                 /* decrypt if enabled */
 716                 if (dsp->bf_enable)
 717                         dsp_bf_decrypt(dsp, skb->data, skb->len);
 718                 /* pipeline */
 719                 if (dsp->pipeline.inuse)
 720                         dsp_pipeline_process_rx(&dsp->pipeline, skb->data,
 721                                                 skb->len, hh->id);
 722                 /* change volume if requested */
 723                 if (dsp->rx_volume)
 724                         dsp_change_volume(skb, dsp->rx_volume);
 725                 /* check if dtmf soft decoding is turned on */
 726                 if (dsp->dtmf.software) {
 727                         digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
 728                                                           skb->len, (dsp_options & DSP_OPT_ULAW) ? 1 : 0);
 729                 }
 730                 /* we need to process receive data if software */
 731                 if (dsp->conf && dsp->conf->software) {
 732                         /* process data from card at cmx */
 733                         dsp_cmx_receive(dsp, skb);
 734                 }
 735
 736                 spin_unlock_irqrestore(&dsp_lock, flags);
 737
 738                 /* send dtmf result, if any */
 739                 if (digits) {
 740                         while (*digits) {
 741                                 int k;
 742                                 struct sk_buff *nskb;
 743                                 if (dsp_debug & DEBUG_DSP_DTMF)
 744                                         printk(KERN_DEBUG "%s: digit"
 745                                                "(%c) to layer %s\n",
 746                                                __func__, *digits, dsp->name);
 747                                 k = *digits | DTMF_TONE_VAL;
 748                                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
 749                                                         MISDN_ID_ANY, sizeof(int), &k,
 750                                                         GFP_ATOMIC);
 751                                 if (nskb) {
 752                                         if (dsp->up) {
 753                                                 if (dsp->up->send(
 754                                                             dsp->up, nskb))
 755                                                         dev_kfree_skb(nskb);
 756                                         } else
 757                                                 dev_kfree_skb(nskb);
 758                                 }
 759                                 digits++;
 760                         }
 761                 }
 762                 if (dsp->rx_disabled) {
 763                         /* if receive is not allowed */
 764                         break;
 765                 }
 766                 hh->prim = DL_DATA_IND;
 767                 if (dsp->up)
 768                         return dsp->up->send(dsp->up, skb);
 769                 break;
 770         case (PH_CONTROL_IND):
 771                 if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
 772                         printk(KERN_DEBUG "%s: PH_CONTROL INDICATION "
 773                                "received: %x (len %d) %s\n", __func__,
 774                                hh->id, skb->len, dsp->name);
 775                 switch (hh->id) {
 776                 case (DTMF_HFC_COEF): /* getting coefficients */
 777                         if (!dsp->dtmf.hardware) {
 778                                 if (dsp_debug & DEBUG_DSP_DTMFCOEFF)
 779                                         printk(KERN_DEBUG "%s: ignoring DTMF "
 780                                                "coefficients from HFC\n",
 781                                                __func__);
 782                                 break;
 783                         }
 784                         digits = dsp_dtmf_goertzel_decode(dsp, skb->data,
 785                                                           skb->len, 2);
 786                         while (*digits) {
 787                                 int k;
 788                                 struct sk_buff *nskb;
 789                                 if (dsp_debug & DEBUG_DSP_DTMF)
 790                                         printk(KERN_DEBUG "%s: digit"
 791                                                "(%c) to layer %s\n",
 792                                                __func__, *digits, dsp->name);
 793                                 k = *digits | DTMF_TONE_VAL;
 794                                 nskb = _alloc_mISDN_skb(PH_CONTROL_IND,
 795                                                         MISDN_ID_ANY, sizeof(int), &k,
 796                                                         GFP_ATOMIC);
 797                                 if (nskb) {
 798                                         if (dsp->up) {
 799                                                 if (dsp->up->send(
 800                                                             dsp->up, nskb))
 801                                                         dev_kfree_skb(nskb);
 802                                         } else
 803                                                 dev_kfree_skb(nskb);
 804                                 }
 805                                 digits++;
 806                         }
 807                         break;
 808                 case (HFC_VOL_CHANGE_TX): /* change volume */
 809                         if (skb->len != sizeof(int)) {
 810                                 ret = -EINVAL;
 811                                 break;
 812                         }
 813                         spin_lock_irqsave(&dsp_lock, flags);
 814                         dsp->tx_volume = *((int *)skb->data);
 815                         if (dsp_debug & DEBUG_DSP_CORE)
 816                                 printk(KERN_DEBUG "%s: change tx volume to "
 817                                        "%d\n", __func__, dsp->tx_volume);
 818                         dsp_cmx_hardware(dsp->conf, dsp);
 819                         dsp_dtmf_hardware(dsp);
 820                         dsp_rx_off(dsp);
 821                         spin_unlock_irqrestore(&dsp_lock, flags);
 822                         break;
 823                 default:
 824                         if (dsp_debug & DEBUG_DSP_CORE)
 825                                 printk(KERN_DEBUG "%s: ctrl ind %x unhandled "
 826                                        "%s\n", __func__, hh->id, dsp->name);
 827                         ret = -EINVAL;
 828                 }
 829                 break;
 830         case (PH_ACTIVATE_IND):
 831         case (PH_ACTIVATE_CNF):
 832                 if (dsp_debug & DEBUG_DSP_CORE)
 833                         printk(KERN_DEBUG "%s: b_channel is now active %s\n",
 834                                __func__, dsp->name);
 835                 /* bchannel now active */
 836                 spin_lock_irqsave(&dsp_lock, flags);
 837                 dsp->b_active = 1;
 838                 dsp->data_pending = 0;
 839                 dsp->rx_init = 1;
 840                 /* rx_W and rx_R will be adjusted on first frame */
 841                 dsp->rx_W = 0;
 842                 dsp->rx_R = 0;
 843                 memset(dsp->rx_buff, 0, sizeof(dsp->rx_buff));
 844                 dsp_cmx_hardware(dsp->conf, dsp);
 845                 dsp_dtmf_hardware(dsp);
 846                 dsp_rx_off(dsp);
 847                 spin_unlock_irqrestore(&dsp_lock, flags);
 848                 if (dsp_debug & DEBUG_DSP_CORE)
 849                         printk(KERN_DEBUG "%s: done with activation, sending "
 850                                "confirm to user space. %s\n", __func__,
 851                                dsp->name);
 852                 /* send activation to upper layer */
 853                 hh->prim = DL_ESTABLISH_CNF;
 854                 if (dsp->up)
 855                         return dsp->up->send(dsp->up, skb);
 856                 break;
 857         case (PH_DEACTIVATE_IND):
 858         case (PH_DEACTIVATE_CNF):
 859                 if (dsp_debug & DEBUG_DSP_CORE)
 860                         printk(KERN_DEBUG "%s: b_channel is now inactive %s\n",
 861                                __func__, dsp->name);
 862                 /* bchannel now inactive */
 863                 spin_lock_irqsave(&dsp_lock, flags);
 864                 dsp->b_active = 0;
 865                 dsp->data_pending = 0;
 866                 dsp_cmx_hardware(dsp->conf, dsp);
 867                 dsp_rx_off(dsp);
 868                 spin_unlock_irqrestore(&dsp_lock, flags);
 869                 hh->prim = DL_RELEASE_CNF;
 870                 if (dsp->up)
 871                         return dsp->up->send(dsp->up, skb);
 872                 break;
 873                 /* FROM UP */
 874         case (DL_DATA_REQ):
 875         case (PH_DATA_REQ):
 876                 if (skb->len < 1) {
 877                         ret = -EINVAL;
 878                         break;
 879                 }
 880                 if (dsp->hdlc) {
 881                         /* hdlc */
 882                         if (!dsp->b_active) {
 883                                 ret = -EIO;
 884                                 break;
 885                         }
 886                         hh->prim = PH_DATA_REQ;
 887                         spin_lock_irqsave(&dsp_lock, flags);
 888                         skb_queue_tail(&dsp->sendq, skb);
 889                         schedule_work(&dsp->workq);
 890                         spin_unlock_irqrestore(&dsp_lock, flags);
 891                         return 0;
 892                 }
 893                 /* send data to tx-buffer (if no tone is played) */
 894                 if (!dsp->tone.tone) {
 895                         spin_lock_irqsave(&dsp_lock, flags);
 896                         dsp_cmx_transmit(dsp, skb);
 897                         spin_unlock_irqrestore(&dsp_lock, flags);
 898                 }
 899                 break;
 900         case (PH_CONTROL_REQ):
 901                 spin_lock_irqsave(&dsp_lock, flags);
 902                 ret = dsp_control_req(dsp, hh, skb);
 903                 spin_unlock_irqrestore(&dsp_lock, flags);
 904                 break;
 905         case (DL_ESTABLISH_REQ):
 906         case (PH_ACTIVATE_REQ):
 907                 if (dsp_debug & DEBUG_DSP_CORE)
 908                         printk(KERN_DEBUG "%s: activating b_channel %s\n",
 909                                __func__, dsp->name);
 910                 if (dsp->dtmf.hardware || dsp->dtmf.software)
 911                         dsp_dtmf_goertzel_init(dsp);
 912                 get_features(ch);
 913                 /* enable fill_empty feature */
 914                 if (dsp->features_fill_empty)
 915                         dsp_fill_empty(dsp);
 916                 /* send ph_activate */
 917                 hh->prim = PH_ACTIVATE_REQ;
 918                 if (ch->peer)
 919                         return ch->recv(ch->peer, skb);
 920                 break;
 921         case (DL_RELEASE_REQ):
 922         case (PH_DEACTIVATE_REQ):
 923                 if (dsp_debug & DEBUG_DSP_CORE)
 924                         printk(KERN_DEBUG "%s: releasing b_channel %s\n",
 925                                __func__, dsp->name);
 926                 spin_lock_irqsave(&dsp_lock, flags);
 927                 dsp->tone.tone = 0;
 928                 dsp->tone.hardware = 0;
 929                 dsp->tone.software = 0;
 930                 if (timer_pending(&dsp->tone.tl))
 931                         del_timer(&dsp->tone.tl);
 932                 if (dsp->conf)
 933                         dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be
 934                                                  called here */
 935                 skb_queue_purge(&dsp->sendq);
 936                 spin_unlock_irqrestore(&dsp_lock, flags);
 937                 hh->prim = PH_DEACTIVATE_REQ;
 938                 if (ch->peer)
 939                         return ch->recv(ch->peer, skb);
 940                 break;
 941         default:
 942                 if (dsp_debug & DEBUG_DSP_CORE)
 943                         printk(KERN_DEBUG "%s: msg %x unhandled %s\n",
 944                                __func__, hh->prim, dsp->name);
 945                 ret = -EINVAL;
 946         }
 947         if (!ret)
 948                 dev_kfree_skb(skb);
 949         return ret;
 950 }
 951
 952 static int
 953 dsp_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
 954 {
 955         struct dsp              *dsp = container_of(ch, struct dsp, ch);
 956         u_long          flags;
 957
 958         if (debug & DEBUG_DSP_CTRL)
 959                 printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
 960
 961         switch (cmd) {
 962         case OPEN_CHANNEL:
 963                 break;
 964         case CLOSE_CHANNEL:
 965                 if (dsp->ch.peer)
 966                         dsp->ch.peer->ctrl(dsp->ch.peer, CLOSE_CHANNEL, NULL);
 967
 968                 /* wait until workqueue has finished,
 969                  * must lock here, or we may hit send-process currently
 970                  * queueing. */
 971                 spin_lock_irqsave(&dsp_lock, flags);
 972                 dsp->b_active = 0;
 973                 spin_unlock_irqrestore(&dsp_lock, flags);
 974                 /* MUST not be locked, because it waits until queue is done. */
 975                 cancel_work_sync(&dsp->workq);
 976                 spin_lock_irqsave(&dsp_lock, flags);
 977                 if (timer_pending(&dsp->tone.tl))
 978                         del_timer(&dsp->tone.tl);
 979                 skb_queue_purge(&dsp->sendq);
 980                 if (dsp_debug & DEBUG_DSP_CTRL)
 981                         printk(KERN_DEBUG "%s: releasing member %s\n",
 982                                __func__, dsp->name);
 983                 dsp->b_active = 0;
 984                 dsp_cmx_conf(dsp, 0); /* dsp_cmx_hardware will also be called
 985                                          here */
 986                 dsp_pipeline_destroy(&dsp->pipeline);
 987
 988                 if (dsp_debug & DEBUG_DSP_CTRL)
 989                         printk(KERN_DEBUG "%s: remove & destroy object %s\n",
 990                                __func__, dsp->name);
 991                 list_del(&dsp->list);
 992                 spin_unlock_irqrestore(&dsp_lock, flags);
 993
 994                 if (dsp_debug & DEBUG_DSP_CTRL)
 995                         printk(KERN_DEBUG "%s: dsp instance released\n",
 996                                __func__);
 997                 vfree(dsp);
 998                 module_put(THIS_MODULE);
 999                 break;
1000         }
1001         return 0;
1002 }
1003
1004 static void
1005 dsp_send_bh(struct work_struct *work)
1006 {
1007         struct dsp *dsp = container_of(work, struct dsp, workq);
1008         struct sk_buff *skb;
1009         struct mISDNhead        *hh;
1010
1011         if (dsp->hdlc && dsp->data_pending)
1012                 return; /* wait until data has been acknowledged */
1013
1014         /* send queued data */
1015         while ((skb = skb_dequeue(&dsp->sendq))) {
1016                 /* in locked date, we must have still data in queue */
1017                 if (dsp->data_pending) {
1018                         if (dsp_debug & DEBUG_DSP_CORE)
1019                                 printk(KERN_DEBUG "%s: fifo full %s, this is "
1020                                        "no bug!\n", __func__, dsp->name);
1021                         /* flush transparent data, if not acked */
1022                         dev_kfree_skb(skb);
1023                         continue;
1024                 }
1025                 hh = mISDN_HEAD_P(skb);
1026                 if (hh->prim == DL_DATA_REQ) {
1027                         /* send packet up */
1028                         if (dsp->up) {
1029                                 if (dsp->up->send(dsp->up, skb))
1030                                         dev_kfree_skb(skb);
1031                         } else
1032                                 dev_kfree_skb(skb);
1033                 } else {
1034                         /* send packet down */
1035                         if (dsp->ch.peer) {
1036                                 dsp->data_pending = 1;
1037                                 if (dsp->ch.recv(dsp->ch.peer, skb)) {
1038                                         dev_kfree_skb(skb);
1039                                         dsp->data_pending = 0;
1040                                 }
1041                         } else
1042                                 dev_kfree_skb(skb);
1043                 }
1044         }
1045 }
1046
1047 static int
1048 dspcreate(struct channel_req *crq)
1049 {
1050         struct dsp              *ndsp;
1051         u_long          flags;
1052
1053         if (crq->protocol != ISDN_P_B_L2DSP
1054             && crq->protocol != ISDN_P_B_L2DSPHDLC)
1055                 return -EPROTONOSUPPORT;
1056         ndsp = vzalloc(sizeof(struct dsp));
1057         if (!ndsp) {
1058                 printk(KERN_ERR "%s: vmalloc struct dsp failed\n", __func__);
1059                 return -ENOMEM;
1060         }
1061         if (dsp_debug & DEBUG_DSP_CTRL)
1062                 printk(KERN_DEBUG "%s: creating new dsp instance\n", __func__);
1063
1064         /* default enabled */
1065         INIT_WORK(&ndsp->workq, (void *)dsp_send_bh);
1066         skb_queue_head_init(&ndsp->sendq);
1067         ndsp->ch.send = dsp_function;
1068         ndsp->ch.ctrl = dsp_ctrl;
1069         ndsp->up = crq->ch;
1070         crq->ch = &ndsp->ch;
1071         if (crq->protocol == ISDN_P_B_L2DSP) {
1072                 crq->protocol = ISDN_P_B_RAW;
1073                 ndsp->hdlc = 0;
1074         } else {
1075                 crq->protocol = ISDN_P_B_HDLC;
1076                 ndsp->hdlc = 1;
1077         }
1078         if (!try_module_get(THIS_MODULE))
1079                 printk(KERN_WARNING "%s:cannot get module\n",
1080                        __func__);
1081
1082         sprintf(ndsp->name, "DSP_C%x(0x%p)",
1083                 ndsp->up->st->dev->id + 1, ndsp);
1084         /* set frame size to start */
1085         ndsp->features.hfc_id = -1; /* current PCM id */
1086         ndsp->features.pcm_id = -1; /* current PCM id */
1087         ndsp->pcm_slot_rx = -1; /* current CPM slot */
1088         ndsp->pcm_slot_tx = -1;
1089         ndsp->pcm_bank_rx = -1;
1090         ndsp->pcm_bank_tx = -1;
1091         ndsp->hfc_conf = -1; /* current conference number */
1092         /* set tone timer */
1093         timer_setup(&ndsp->tone.tl, dsp_tone_timeout, 0);
1094
1095         if (dtmfthreshold < 20 || dtmfthreshold > 500)
1096                 dtmfthreshold = 200;
1097         ndsp->dtmf.treshold = dtmfthreshold * 10000;
1098
1099         /* init pipeline append to list */
1100         spin_lock_irqsave(&dsp_lock, flags);
1101         dsp_pipeline_init(&ndsp->pipeline);
1102         list_add_tail(&ndsp->list, &dsp_ilist);
1103         spin_unlock_irqrestore(&dsp_lock, flags);
1104
1105         return 0;
1106 }
1107
1108
1109 static struct Bprotocol DSP = {
1110         .Bprotocols = (1 << (ISDN_P_B_L2DSP & ISDN_P_B_MASK))
1111         | (1 << (ISDN_P_B_L2DSPHDLC & ISDN_P_B_MASK)),
1112         .name = "dsp",
1113         .create = dspcreate
1114 };
1115
1116 static int __init dsp_init(void)
1117 {
1118         int err;
1119         int tics;
1120
1121         printk(KERN_INFO "DSP module %s\n", mISDN_dsp_revision);
1122
1123         dsp_options = options;
1124         dsp_debug = debug;
1125
1126         /* set packet size */
1127         dsp_poll = poll;
1128         if (dsp_poll) {
1129                 if (dsp_poll > MAX_POLL) {
1130                         printk(KERN_ERR "%s: Wrong poll value (%d), use %d "
1131                                "maximum.\n", __func__, poll, MAX_POLL);
1132                         err = -EINVAL;
1133                         return err;
1134                 }
1135                 if (dsp_poll < 8) {
1136                         printk(KERN_ERR "%s: Wrong poll value (%d), use 8 "
1137                                "minimum.\n", __func__, dsp_poll);
1138                         err = -EINVAL;
1139                         return err;
1140                 }
1141                 dsp_tics = poll * HZ / 8000;
1142                 if (dsp_tics * 8000 != poll * HZ) {
1143                         printk(KERN_INFO "mISDN_dsp: Cannot clock every %d "
1144                                "samples (0,125 ms). It is not a multiple of "
1145                                "%d HZ.\n", poll, HZ);
1146                         err = -EINVAL;
1147                         return err;
1148                 }
1149         } else {
1150                 poll = 8;
1151                 while (poll <= MAX_POLL) {
1152                         tics = (poll * HZ) / 8000;
1153                         if (tics * 8000 == poll * HZ) {
1154                                 dsp_tics = tics;
1155                                 dsp_poll = poll;
1156                                 if (poll >= 64)
1157                                         break;
1158                         }
1159                         poll++;
1160                 }
1161         }
1162         if (dsp_poll == 0) {
1163                 printk(KERN_INFO "mISDN_dsp: There is no multiple of kernel "
1164                        "clock that equals exactly the duration of 8-256 "
1165                        "samples. (Choose kernel clock speed like 100, 250, "
1166                        "300, 1000)\n");
1167                 err = -EINVAL;
1168                 return err;
1169         }
1170         printk(KERN_INFO "mISDN_dsp: DSP clocks every %d samples. This equals "
1171                "%d jiffies.\n", dsp_poll, dsp_tics);
1172
1173         /* init conversion tables */
1174         dsp_audio_generate_law_tables();
1175         dsp_silence = (dsp_options & DSP_OPT_ULAW) ? 0xff : 0x2a;
1176         dsp_audio_law_to_s32 = (dsp_options & DSP_OPT_ULAW) ?
1177                 dsp_audio_ulaw_to_s32 : dsp_audio_alaw_to_s32;
1178         dsp_audio_generate_s2law_table();
1179         dsp_audio_generate_seven();
1180         dsp_audio_generate_mix_table();
1181         if (dsp_options & DSP_OPT_ULAW)
1182                 dsp_audio_generate_ulaw_samples();
1183         dsp_audio_generate_volume_changes();
1184
1185         err = dsp_pipeline_module_init();
1186         if (err) {
1187                 printk(KERN_ERR "mISDN_dsp: Can't initialize pipeline, "
1188                        "error(%d)\n", err);
1189                 return err;
1190         }
1191
1192         err = mISDN_register_Bprotocol(&DSP);
1193         if (err) {
1194                 printk(KERN_ERR "Can't register %s error(%d)\n", DSP.name, err);
1195                 return err;
1196         }
1197
1198         /* set sample timer */
1199         timer_setup(&dsp_spl_tl, dsp_cmx_send, 0);
1200         dsp_spl_tl.expires = jiffies + dsp_tics;
1201         dsp_spl_jiffies = dsp_spl_tl.expires;
1202         add_timer(&dsp_spl_tl);
1203
1204         return 0;
1205 }
1206
1207
1208 static void __exit dsp_cleanup(void)
1209 {
1210         mISDN_unregister_Bprotocol(&DSP);
1211
1212         del_timer_sync(&dsp_spl_tl);
1213
1214         if (!list_empty(&dsp_ilist)) {
1215                 printk(KERN_ERR "mISDN_dsp: Audio DSP object inst list not "
1216                        "empty.\n");
1217         }
1218         if (!list_empty(&conf_ilist)) {
1219                 printk(KERN_ERR "mISDN_dsp: Conference list not empty. Not "
1220                        "all memory freed.\n");
1221         }
1222
1223         dsp_pipeline_module_exit();
1224 }
1225
1226 module_init(dsp_init);
1227 module_exit(dsp_cleanup);