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