drivers/isdn/mISDN/dsp_core.c

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