codecs/codec_dahdi.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * DAHDI native transcoding support
   5  *
   6  * Copyright (C) 1999 - 2008, Digium, Inc.
   7  *
   8  * Mark Spencer <markster@digium.com>
   9  * Kevin P. Fleming <kpfleming@digium.com>
  10  *
  11  * See http://www.asterisk.org for more information about
  12  * the Asterisk project. Please do not directly contact
  13  * any of the maintainers of this project for assistance;
  14  * the project provides a web site, mailing lists and IRC
  15  * channels for your use.
  16  *
  17  * This program is free software, distributed under the terms of
  18  * the GNU General Public License Version 2. See the LICENSE file
  19  * at the top of the source tree.
  20  */
  21
  22 /*! \file
  23  *
  24  * \brief Translate between various formats natively through DAHDI transcoding
  25  *
  26  * \ingroup codecs
  27  */
  28
  29 /*** MODULEINFO
  30         <depend>dahdi</depend>
  31  ***/
  32
  33 #include "asterisk.h"
  34
  35 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  36
  37 #include <fcntl.h>
  38 #include <netinet/in.h>
  39 #include <sys/ioctl.h>
  40 #include <sys/mman.h>
  41 #include <sys/poll.h>
  42 #include <dahdi/user.h>
  43
  44 #include "asterisk/lock.h"
  45 #include "asterisk/translate.h"
  46 #include "asterisk/config.h"
  47 #include "asterisk/module.h"
  48 #include "asterisk/cli.h"
  49 #include "asterisk/channel.h"
  50 #include "asterisk/utils.h"
  51 #include "asterisk/linkedlists.h"
  52 #include "asterisk/ulaw.h"
  53
  54 #define BUFFER_SIZE 8000
  55
  56 #define G723_SAMPLES 240
  57 #define G729_SAMPLES 160
  58
  59 static struct channel_usage {
  60         int total;
  61         int encoders;
  62         int decoders;
  63 } channels;
  64
  65 static char *handle_cli_transcoder_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a);
  66
  67 static struct ast_cli_entry cli[] = {
  68         AST_CLI_DEFINE(handle_cli_transcoder_show, "Display DAHDI transcoder utilization.")
  69 };
  70
  71 struct format_map {
  72         unsigned int map[32][32];
  73 };
  74
  75 static struct format_map global_format_map = { { { 0 } } };
  76
  77 struct translator {
  78         struct ast_translator t;
  79         AST_LIST_ENTRY(translator) entry;
  80 };
  81
  82 static AST_LIST_HEAD_STATIC(translators, translator);
  83
  84 struct codec_dahdi_pvt {
  85         int fd;
  86         struct dahdi_transcoder_formats fmts;
  87         unsigned int softslin:1;
  88         unsigned int fake:2;
  89         uint16_t required_samples;
  90         uint16_t samples_in_buffer;
  91         uint8_t ulaw_buffer[1024];
  92 };
  93
  94 /* Only used by a decoder */
  95 static int ulawtolin(struct ast_trans_pvt *pvt)
  96 {
  97         struct codec_dahdi_pvt *dahdip = pvt->pvt;
  98         int i = dahdip->required_samples;
  99         uint8_t *src = &dahdip->ulaw_buffer[0];
 100         int16_t *dst = pvt->outbuf.i16 + pvt->datalen;
 101
 102         /* convert and copy in outbuf */
 103         while (i--) {
 104                 *dst++ = AST_MULAW(*src++);
 105         }
 106
 107         return 0;
 108 }
 109
 110 /* Only used by an encoder. */
 111 static int lintoulaw(struct ast_trans_pvt *pvt, struct ast_frame *f)
 112 {
 113         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 114         int i = f->samples;
 115         uint8_t *dst = &dahdip->ulaw_buffer[dahdip->samples_in_buffer];
 116         int16_t *src = f->data.ptr;
 117
 118         if (dahdip->samples_in_buffer + i > sizeof(dahdip->ulaw_buffer)) {
 119                 ast_log(LOG_ERROR, "Out of buffer space!\n");
 120                 return -i;
 121         }
 122
 123         while (i--) {
 124                 *dst++ = AST_LIN2MU(*src++);
 125         }
 126
 127         dahdip->samples_in_buffer += f->samples;
 128         return 0;
 129 }
 130
 131 static char *handle_cli_transcoder_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
 132 {
 133         struct channel_usage copy;
 134
 135         switch (cmd) {
 136         case CLI_INIT:
 137                 e->command = "transcoder show";
 138                 e->usage =
 139                         "Usage: transcoder show\n"
 140                         "       Displays channel utilization of DAHDI transcoder(s).\n";
 141                 return NULL;
 142         case CLI_GENERATE:
 143                 return NULL;
 144         }
 145
 146         if (a->argc != 2)
 147                 return CLI_SHOWUSAGE;
 148
 149         copy = channels;
 150
 151         if (copy.total == 0)
 152                 ast_cli(a->fd, "No DAHDI transcoders found.\n");
 153         else
 154                 ast_cli(a->fd, "%d/%d encoders/decoders of %d channels are in use.\n", copy.encoders, copy.decoders, copy.total);
 155
 156         return CLI_SUCCESS;
 157 }
 158
 159 static void dahdi_write_frame(struct codec_dahdi_pvt *dahdip, const uint8_t *buffer, const ssize_t count)
 160 {
 161         int res;
 162         struct pollfd p = {0};
 163         if (!count) return;
 164         res = write(dahdip->fd, buffer, count);
 165         if (option_verbose > 10) {
 166                 if (-1 == res) {
 167                         ast_log(LOG_ERROR, "Failed to write to transcoder: %s\n", strerror(errno));
 168                 }
 169                 if (count != res) {
 170                         ast_log(LOG_ERROR, "Requested write of %zd bytes, but only wrote %d bytes.\n", count, res);
 171                 }
 172         }
 173         p.fd = dahdip->fd;
 174         p.events = POLLOUT;
 175         res = poll(&p, 1, 50);
 176 }
 177
 178 static int dahdi_encoder_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 179 {
 180         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 181
 182         if (!f->subclass.codec) {
 183                 /* We're just faking a return for calculation purposes. */
 184                 dahdip->fake = 2;
 185                 pvt->samples = f->samples;
 186                 return 0;
 187         }
 188
 189         /* Buffer up the packets and send them to the hardware if we
 190          * have enough samples set up. */
 191         if (dahdip->softslin) {
 192                 if (lintoulaw(pvt, f)) {
 193                          return -1;
 194                 }
 195         } else {
 196                 /* NOTE:  If softslin support is not needed, and the sample
 197                  * size is equal to the required sample size, we wouldn't
 198                  * need this copy operation.  But at the time this was
 199                  * written, only softslin is supported. */
 200                 if (dahdip->samples_in_buffer + f->samples > sizeof(dahdip->ulaw_buffer)) {
 201                         ast_log(LOG_ERROR, "Out of buffer space.\n");
 202                         return -1;
 203                 }
 204                 memcpy(&dahdip->ulaw_buffer[dahdip->samples_in_buffer], f->data.ptr, f->samples);
 205                 dahdip->samples_in_buffer += f->samples;
 206         }
 207
 208         while (dahdip->samples_in_buffer > dahdip->required_samples) {
 209                 dahdi_write_frame(dahdip, dahdip->ulaw_buffer, dahdip->required_samples);
 210                 dahdip->samples_in_buffer -= dahdip->required_samples;
 211                 if (dahdip->samples_in_buffer) {
 212                         /* Shift any remaining bytes down. */
 213                         memmove(dahdip->ulaw_buffer, &dahdip->ulaw_buffer[dahdip->required_samples],
 214                                 dahdip->samples_in_buffer);
 215                 }
 216         }
 217         pvt->samples += f->samples;
 218         pvt->datalen = 0;
 219         return -1;
 220 }
 221
 222 static struct ast_frame *dahdi_encoder_frameout(struct ast_trans_pvt *pvt)
 223 {
 224         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 225         int res;
 226
 227         if (2 == dahdip->fake) {
 228                 dahdip->fake = 1;
 229                 pvt->f.frametype = AST_FRAME_VOICE;
 230                 pvt->f.subclass.codec = 0;
 231                 pvt->f.samples = dahdip->required_samples;
 232                 pvt->f.data.ptr = NULL;
 233                 pvt->f.offset = 0;
 234                 pvt->f.datalen = 0;
 235                 pvt->f.mallocd = 0;
 236                 pvt->samples = 0;
 237
 238                 return ast_frisolate(&pvt->f);
 239
 240         } else if (1 == dahdip->fake) {
 241                 dahdip->fake = 0;
 242                 return NULL;
 243         }
 244
 245         res = read(dahdip->fd, pvt->outbuf.c + pvt->datalen, pvt->t->buf_size - pvt->datalen);
 246         if (-1 == res) {
 247                 if (EWOULDBLOCK == errno) {
 248                         /* Nothing waiting... */
 249                         return NULL;
 250                 } else {
 251                         ast_log(LOG_ERROR, "Failed to read from transcoder: %s\n", strerror(errno));
 252                         return NULL;
 253                 }
 254         } else {
 255                 pvt->f.datalen = res;
 256                 pvt->f.samples = dahdip->required_samples;
 257                 pvt->f.frametype = AST_FRAME_VOICE;
 258                 pvt->f.subclass.codec = 1 <<  (pvt->t->dstfmt);
 259                 pvt->f.mallocd = 0;
 260                 pvt->f.offset = AST_FRIENDLY_OFFSET;
 261                 pvt->f.src = pvt->t->name;
 262                 pvt->f.data.ptr = pvt->outbuf.c;
 263
 264                 pvt->samples = 0;
 265                 pvt->datalen = 0;
 266                 return ast_frisolate(&pvt->f);
 267         }
 268
 269         /* Shouldn't get here... */
 270         return NULL;
 271 }
 272
 273 static int dahdi_decoder_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 274 {
 275         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 276
 277         if (!f->subclass.codec) {
 278                 /* We're just faking a return for calculation purposes. */
 279                 dahdip->fake = 2;
 280                 pvt->samples = f->samples;
 281                 return 0;
 282         }
 283
 284         if (!f->datalen) {
 285                 if (f->samples != dahdip->required_samples) {
 286                         ast_log(LOG_ERROR, "%d != %d %d\n", f->samples, dahdip->required_samples, f->datalen);
 287                 }
 288         }
 289         dahdi_write_frame(dahdip, f->data.ptr, f->datalen);
 290         pvt->samples += f->samples;
 291         pvt->datalen = 0;
 292         return -1;
 293 }
 294
 295 static struct ast_frame *dahdi_decoder_frameout(struct ast_trans_pvt *pvt)
 296 {
 297         int res;
 298         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 299
 300         if (2 == dahdip->fake) {
 301                 dahdip->fake = 1;
 302                 pvt->f.frametype = AST_FRAME_VOICE;
 303                 pvt->f.subclass.codec = 0;
 304                 pvt->f.samples = dahdip->required_samples;
 305                 pvt->f.data.ptr = NULL;
 306                 pvt->f.offset = 0;
 307                 pvt->f.datalen = 0;
 308                 pvt->f.mallocd = 0;
 309                 pvt->samples = 0;
 310                 return ast_frisolate(&pvt->f);
 311         } else if (1 == dahdip->fake) {
 312                 pvt->samples = 0;
 313                 dahdip->fake = 0;
 314                 return NULL;
 315         }
 316
 317         /* Let's check to see if there is a new frame for us.... */
 318         if (dahdip->softslin) {
 319                 res = read(dahdip->fd, dahdip->ulaw_buffer, sizeof(dahdip->ulaw_buffer));
 320         } else {
 321                 res = read(dahdip->fd, pvt->outbuf.c + pvt->datalen, pvt->t->buf_size - pvt->datalen);
 322         }
 323
 324         if (-1 == res) {
 325                 if (EWOULDBLOCK == errno) {
 326                         /* Nothing waiting... */
 327                         return NULL;
 328                 } else {
 329                         ast_log(LOG_ERROR, "Failed to read from transcoder: %s\n", strerror(errno));
 330                         return NULL;
 331                 }
 332         } else {
 333                 if (dahdip->softslin) {
 334                         ulawtolin(pvt);
 335                         pvt->f.datalen = res * 2;
 336                 } else {
 337                         pvt->f.datalen = res;
 338                 }
 339                 pvt->datalen = 0;
 340                 pvt->f.frametype = AST_FRAME_VOICE;
 341                 pvt->f.subclass.codec = 1 <<  (pvt->t->dstfmt);
 342                 pvt->f.mallocd = 0;
 343                 pvt->f.offset = AST_FRIENDLY_OFFSET;
 344                 pvt->f.src = pvt->t->name;
 345                 pvt->f.data.ptr = pvt->outbuf.c;
 346                 pvt->f.samples = dahdip->required_samples;
 347                 pvt->samples = 0;
 348
 349                 return ast_frisolate(&pvt->f);
 350         }
 351
 352         /* Shouldn't get here... */
 353         return NULL;
 354 }
 355
 356
 357 static void dahdi_destroy(struct ast_trans_pvt *pvt)
 358 {
 359         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 360
 361         switch (dahdip->fmts.dstfmt) {
 362         case AST_FORMAT_G729A:
 363         case AST_FORMAT_G723_1:
 364                 ast_atomic_fetchadd_int(&channels.encoders, -1);
 365                 break;
 366         default:
 367                 ast_atomic_fetchadd_int(&channels.decoders, -1);
 368                 break;
 369         }
 370
 371         close(dahdip->fd);
 372 }
 373
 374 static int dahdi_translate(struct ast_trans_pvt *pvt, int dest, int source)
 375 {
 376         /* Request translation through zap if possible */
 377         int fd;
 378         struct codec_dahdi_pvt *dahdip = pvt->pvt;
 379         int flags;
 380         int tried_once = 0;
 381         const char *dev_filename = "/dev/dahdi/transcode";
 382
 383         if ((fd = open(dev_filename, O_RDWR)) < 0) {
 384                 ast_log(LOG_ERROR, "Failed to open %s: %s\n", dev_filename, strerror(errno));
 385                 return -1;
 386         }
 387
 388         dahdip->fmts.srcfmt = (1 << source);
 389         dahdip->fmts.dstfmt = (1 << dest);
 390
 391         ast_debug(1, "Opening transcoder channel from %d to %d.\n", source, dest);
 392
 393 retry:
 394         if (ioctl(fd, DAHDI_TC_ALLOCATE, &dahdip->fmts)) {
 395                 if ((ENODEV == errno) && !tried_once) {
 396                         /* We requested to translate to/from an unsupported
 397                          * format.  Most likely this is because signed linear
 398                          * was not supported by any hardware devices even
 399                          * though this module always registers signed linear
 400                          * support. In this case we'll retry, requesting
 401                          * support for ULAW instead of signed linear and then
 402                          * we'll just convert from ulaw to signed linear in
 403                          * software. */
 404                         if (AST_FORMAT_SLINEAR == dahdip->fmts.srcfmt) {
 405                                 ast_debug(1, "Using soft_slin support on source\n");
 406                                 dahdip->softslin = 1;
 407                                 dahdip->fmts.srcfmt = AST_FORMAT_ULAW;
 408                         } else if (AST_FORMAT_SLINEAR == dahdip->fmts.dstfmt) {
 409                                 ast_debug(1, "Using soft_slin support on destination\n");
 410                                 dahdip->softslin = 1;
 411                                 dahdip->fmts.dstfmt = AST_FORMAT_ULAW;
 412                         }
 413                         tried_once = 1;
 414                         goto retry;
 415                 }
 416                 ast_log(LOG_ERROR, "Unable to attach to transcoder: %s\n", strerror(errno));
 417                 close(fd);
 418
 419                 return -1;
 420         }
 421
 422         flags = fcntl(fd, F_GETFL);
 423         if (flags > - 1) {
 424                 if (fcntl(fd, F_SETFL, flags | O_NONBLOCK))
 425                         ast_log(LOG_WARNING, "Could not set non-block mode!\n");
 426         }
 427
 428         dahdip->fd = fd;
 429
 430         dahdip->required_samples = ((dahdip->fmts.dstfmt|dahdip->fmts.srcfmt)&AST_FORMAT_G723_1) ? G723_SAMPLES : G729_SAMPLES;
 431
 432         switch (dahdip->fmts.dstfmt) {
 433         case AST_FORMAT_G729A:
 434                 ast_atomic_fetchadd_int(&channels.encoders, +1);
 435                 break;
 436         case AST_FORMAT_G723_1:
 437                 ast_atomic_fetchadd_int(&channels.encoders, +1);
 438                 break;
 439         default:
 440                 ast_atomic_fetchadd_int(&channels.decoders, +1);
 441                 break;
 442         }
 443
 444         return 0;
 445 }
 446
 447 static int dahdi_new(struct ast_trans_pvt *pvt)
 448 {
 449         return dahdi_translate(pvt, pvt->t->dstfmt, pvt->t->srcfmt);
 450 }
 451
 452 static struct ast_frame *fakesrc_sample(void)
 453 {
 454         /* Don't bother really trying to test hardware ones. */
 455         static struct ast_frame f = {
 456                 .frametype = AST_FRAME_VOICE,
 457                 .samples = 160,
 458                 .src = __PRETTY_FUNCTION__
 459         };
 460
 461         return &f;
 462 }
 463
 464 static int is_encoder(struct translator *zt)
 465 {
 466         if (zt->t.srcfmt&(AST_FORMAT_ULAW|AST_FORMAT_ALAW|AST_FORMAT_SLINEAR)) {
 467                 return 1;
 468         } else {
 469                 return 0;
 470         }
 471 }
 472
 473 static int register_translator(int dst, int src)
 474 {
 475         struct translator *zt;
 476         int res;
 477
 478         if (!(zt = ast_calloc(1, sizeof(*zt)))) {
 479                 return -1;
 480         }
 481
 482         snprintf((char *) (zt->t.name), sizeof(zt->t.name), "zap%sto%s",
 483                  ast_getformatname((1 << src)), ast_getformatname((1 << dst)));
 484         zt->t.srcfmt = (1 << src);
 485         zt->t.dstfmt = (1 << dst);
 486         zt->t.buf_size = BUFFER_SIZE;
 487         if (is_encoder(zt)) {
 488                 zt->t.framein = dahdi_encoder_framein;
 489                 zt->t.frameout = dahdi_encoder_frameout;
 490         } else {
 491                 zt->t.framein = dahdi_decoder_framein;
 492                 zt->t.frameout = dahdi_decoder_frameout;
 493         }
 494         zt->t.destroy = dahdi_destroy;
 495         zt->t.buffer_samples = 0;
 496         zt->t.newpvt = dahdi_new;
 497         zt->t.sample = fakesrc_sample;
 498         zt->t.native_plc = 0;
 499
 500         zt->t.desc_size = sizeof(struct codec_dahdi_pvt);
 501         if ((res = ast_register_translator(&zt->t))) {
 502                 ast_free(zt);
 503                 return -1;
 504         }
 505
 506         AST_LIST_LOCK(&translators);
 507         AST_LIST_INSERT_HEAD(&translators, zt, entry);
 508         AST_LIST_UNLOCK(&translators);
 509
 510         global_format_map.map[dst][src] = 1;
 511
 512         return res;
 513 }
 514
 515 static void drop_translator(int dst, int src)
 516 {
 517         struct translator *cur;
 518
 519         AST_LIST_LOCK(&translators);
 520         AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, cur, entry) {
 521                 if (cur->t.srcfmt != src)
 522                         continue;
 523
 524                 if (cur->t.dstfmt != dst)
 525                         continue;
 526
 527                 AST_LIST_REMOVE_CURRENT(entry);
 528                 ast_unregister_translator(&cur->t);
 529                 ast_free(cur);
 530                 global_format_map.map[dst][src] = 0;
 531                 break;
 532         }
 533         AST_LIST_TRAVERSE_SAFE_END;
 534         AST_LIST_UNLOCK(&translators);
 535 }
 536
 537 static void unregister_translators(void)
 538 {
 539         struct translator *cur;
 540
 541         AST_LIST_LOCK(&translators);
 542         while ((cur = AST_LIST_REMOVE_HEAD(&translators, entry))) {
 543                 ast_unregister_translator(&cur->t);
 544                 ast_free(cur);
 545         }
 546         AST_LIST_UNLOCK(&translators);
 547 }
 548
 549 static void build_translators(struct format_map *map, unsigned int dstfmts, unsigned int srcfmts)
 550 {
 551         unsigned int src, dst;
 552
 553         for (src = 0; src < 32; src++) {
 554                 for (dst = 0; dst < 32; dst++) {
 555                         if (!(srcfmts & (1 << src)))
 556                                 continue;
 557
 558                         if (!(dstfmts & (1 << dst)))
 559                                 continue;
 560
 561                         if (global_format_map.map[dst][src])
 562                                 continue;
 563
 564                         if (!register_translator(dst, src))
 565                                 map->map[dst][src] = 1;
 566                 }
 567         }
 568 }
 569
 570 static int find_transcoders(void)
 571 {
 572         struct dahdi_transcoder_info info = { 0, };
 573         struct format_map map = { { { 0 } } };
 574         int fd, res;
 575         unsigned int x, y;
 576
 577         if ((fd = open("/dev/dahdi/transcode", O_RDWR)) < 0) {
 578                 ast_log(LOG_ERROR, "Failed to open /dev/dahdi/transcode: %s\n", strerror(errno));
 579                 return 0;
 580         }
 581
 582         for (info.tcnum = 0; !(res = ioctl(fd, DAHDI_TC_GETINFO, &info)); info.tcnum++) {
 583                 if (option_verbose > 1)
 584                         ast_verbose(VERBOSE_PREFIX_2 "Found transcoder '%s'.\n", info.name);
 585
 586                 /* Complex codecs need to support signed linear.  If the
 587                  * hardware transcoder does not natively support signed linear
 588                  * format, we will emulate it in software directly in this
 589                  * module. Also, do not allow direct ulaw/alaw to complex
 590                  * codec translation, since that will prevent the generic PLC
 591                  * functions from working. */
 592                 if (info.dstfmts & (AST_FORMAT_ULAW | AST_FORMAT_ALAW)) {
 593                         info.dstfmts |= AST_FORMAT_SLINEAR;
 594                         info.dstfmts &= ~(AST_FORMAT_ULAW | AST_FORMAT_ALAW);
 595                 }
 596                 if (info.srcfmts & (AST_FORMAT_ULAW | AST_FORMAT_ALAW)) {
 597                         info.srcfmts |= AST_FORMAT_SLINEAR;
 598                         info.srcfmts &= ~(AST_FORMAT_ULAW | AST_FORMAT_ALAW);
 599                 }
 600
 601                 build_translators(&map, info.dstfmts, info.srcfmts);
 602                 ast_atomic_fetchadd_int(&channels.total, info.numchannels / 2);
 603
 604         }
 605
 606         close(fd);
 607
 608         if (!info.tcnum && (option_verbose > 1))
 609                 ast_verbose(VERBOSE_PREFIX_2 "No hardware transcoders found.\n");
 610
 611         for (x = 0; x < 32; x++) {
 612                 for (y = 0; y < 32; y++) {
 613                         if (!map.map[x][y] && global_format_map.map[x][y])
 614                                 drop_translator(x, y);
 615                 }
 616         }
 617
 618         return 0;
 619 }
 620
 621 static int reload(void)
 622 {
 623         struct translator *cur;
 624
 625         return AST_MODULE_LOAD_SUCCESS;
 626 }
 627
 628 static int unload_module(void)
 629 {
 630         ast_cli_unregister_multiple(cli, ARRAY_LEN(cli));
 631         unregister_translators();
 632
 633         return 0;
 634 }
 635
 636 static int load_module(void)
 637 {
 638         ast_ulaw_init();
 639         find_transcoders();
 640         ast_cli_register_multiple(cli, ARRAY_LEN(cli));
 641         return AST_MODULE_LOAD_SUCCESS;
 642 }
 643
 644 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "Generic DAHDI Transcoder Codec Translator",
 645                 .load = load_module,
 646                 .unload = unload_module,
 647                 .reload = reload,
 648                );