sys/dev/sound/pcm/vchan.c

   1 /*-
   2  * Copyright (c) 2001 Cameron Grant <cg@freebsd.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/sys/dev/sound/pcm/vchan.c,v 1.17.2.5 2007/02/04 06:17:14 ariff Exp $
  27  * $DragonFly: src/sys/dev/sound/pcm/vchan.c,v 1.8 2008/01/06 16:55:51 swildner Exp $
  28  */
  29
  30 #include <dev/sound/pcm/sound.h>
  31 #include <dev/sound/pcm/vchan.h>
  32 #include "feeder_if.h"
  33
  34 SND_DECLARE_FILE("$DragonFly: src/sys/dev/sound/pcm/vchan.c,v 1.8 2008/01/06 16:55:51 swildner Exp $");
  35
  36 /*
  37  * Default speed
  38  */
  39 #define VCHAN_DEFAULT_SPEED     48000
  40
  41 extern int feeder_rate_ratemin;
  42 extern int feeder_rate_ratemax;
  43
  44 struct vchinfo {
  45         u_int32_t spd, fmt, blksz, bps, run;
  46         struct pcm_channel *channel, *parent;
  47         struct pcmchan_caps caps;
  48 };
  49
  50 static u_int32_t vchan_fmt[] = {
  51         AFMT_STEREO | AFMT_S16_LE,
  52         0
  53 };
  54
  55 static int
  56 vchan_mix_s16(int16_t *to, int16_t *tmp, unsigned int count, int volume)
  57 {
  58         /*
  59          * to is the output buffer, tmp is the input buffer
  60          * count is the number of 16bit samples to mix
  61          * volume is in range 0-100
  62          */
  63         int i;
  64         int x;
  65         int scale;
  66         int doscale;
  67
  68         scale = (volume << 16) / 100;
  69         doscale = volume != 100;
  70
  71         for(i = 0; i < count; i++) {
  72                 x = to[i];
  73                 if (doscale)
  74                         x += ((int)tmp[i] * scale) >> 16;
  75                 else
  76                         x += tmp[i];
  77                 if (x < -32768) {
  78                         /* kprintf("%d + %d = %d (u)\n", to[i], tmp[i], x); */
  79                         x = -32768;
  80                 }
  81                 if (x > 32767) {
  82                         /* kprintf("%d + %d = %d (o)\n", to[i], tmp[i], x); */
  83                         x = 32767;
  84                 }
  85                 to[i] = x & 0x0000ffff;
  86         }
  87         return 0;
  88 }
  89
  90 static int
  91 feed_vchan_s16(struct pcm_feeder *f, struct pcm_channel *c, u_int8_t *b, u_int32_t count, void *source)
  92 {
  93         /* we're going to abuse things a bit */
  94         struct snd_dbuf *src = source;
  95         struct pcmchan_children *cce;
  96         struct pcm_channel *ch;
  97         uint32_t sz;
  98         int16_t *tmp, *dst;
  99         unsigned int cnt, rcnt = 0;
 100         int volume;
 101
 102         #if 0
 103         if (sndbuf_getsize(src) < count)
 104                 panic("feed_vchan_s16(%s): tmp buffer size %d < count %d, flags = 0x%x",
 105                     c->name, sndbuf_getsize(src), count, c->flags);
 106         #endif
 107         sz = sndbuf_getsize(src);
 108         if (sz < count)
 109                 count = sz;
 110         count &= ~1;
 111         if (count < 2)
 112                 return 0;
 113         bzero(b, count);
 114
 115         /*
 116          * we are going to use our source as a temporary buffer since it's
 117          * got no other purpose.  we obtain our data by traversing the channel
 118          * list of children and calling vchan_mix_* to mix count bytes from each
 119          * into our destination buffer, b
 120          */
 121         dst = (int16_t *)b;
 122         tmp = (int16_t *)sndbuf_getbuf(src);
 123         bzero(tmp, count);
 124         SLIST_FOREACH(cce, &c->children, link) {
 125                 ch = cce->channel;
 126                 CHN_LOCK(ch);
 127                 if (ch->flags & CHN_F_TRIGGERED) {
 128                         if (ch->flags & CHN_F_MAPPED)
 129                                 sndbuf_acquire(ch->bufsoft, NULL, sndbuf_getfree(ch->bufsoft));
 130                         cnt = FEEDER_FEED(ch->feeder, ch, (u_int8_t *)tmp, count, ch->bufsoft);
 131                         volume = ch->volume & 0xff;     /* XXX do special stereo processing? */
 132                         volume += (ch->volume >> 8) & 0xff;
 133                         volume >>= 1;
 134                         vchan_mix_s16(dst, tmp, cnt >> 1, volume);
 135                         if (cnt > rcnt)
 136                                 rcnt = cnt;
 137                 }
 138                 CHN_UNLOCK(ch);
 139         }
 140
 141         return rcnt & ~1;
 142 }
 143
 144 static struct pcm_feederdesc feeder_vchan_s16_desc[] = {
 145         {FEEDER_MIXER, AFMT_S16_LE | AFMT_STEREO, AFMT_S16_LE | AFMT_STEREO, 0},
 146         {0},
 147 };
 148 static kobj_method_t feeder_vchan_s16_methods[] = {
 149         KOBJMETHOD(feeder_feed,         feed_vchan_s16),
 150         { 0, 0 }
 151 };
 152 FEEDER_DECLARE(feeder_vchan_s16, 2, NULL);
 153
 154 /************************************************************/
 155
 156 static void *
 157 vchan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b, struct pcm_channel *c, int dir)
 158 {
 159         struct vchinfo *ch;
 160         struct pcm_channel *parent = devinfo;
 161
 162         KASSERT(dir == PCMDIR_PLAY, ("vchan_init: bad direction"));
 163         ch = kmalloc(sizeof(*ch), M_DEVBUF, M_WAITOK | M_ZERO);
 164         ch->parent = parent;
 165         ch->channel = c;
 166         ch->fmt = AFMT_U8;
 167         ch->spd = DSP_DEFAULT_SPEED;
 168         ch->blksz = 2048;
 169
 170         c->flags |= CHN_F_VIRTUAL;
 171
 172         return ch;
 173 }
 174
 175 static int
 176 vchan_free(kobj_t obj, void *data)
 177 {
 178         kfree(data, M_DEVBUF);
 179         return 0;
 180 }
 181
 182 static int
 183 vchan_setformat(kobj_t obj, void *data, u_int32_t format)
 184 {
 185         struct vchinfo *ch = data;
 186         struct pcm_channel *parent = ch->parent;
 187         struct pcm_channel *channel = ch->channel;
 188
 189         ch->fmt = format;
 190         ch->bps = 1;
 191         ch->bps <<= (ch->fmt & AFMT_STEREO)? 1 : 0;
 192         if (ch->fmt & AFMT_16BIT)
 193                 ch->bps <<= 1;
 194         else if (ch->fmt & AFMT_24BIT)
 195                 ch->bps *= 3;
 196         else if (ch->fmt & AFMT_32BIT)
 197                 ch->bps <<= 2;
 198         CHN_UNLOCK(channel);
 199         chn_notify(parent, CHN_N_FORMAT);
 200         CHN_LOCK(channel);
 201         sndbuf_setfmt(channel->bufsoft, format);
 202         return 0;
 203 }
 204
 205 static int
 206 vchan_setspeed(kobj_t obj, void *data, u_int32_t speed)
 207 {
 208         struct vchinfo *ch = data;
 209         struct pcm_channel *parent = ch->parent;
 210         struct pcm_channel *channel = ch->channel;
 211
 212         ch->spd = speed;
 213         CHN_UNLOCK(channel);
 214         CHN_LOCK(parent);
 215         speed = sndbuf_getspd(parent->bufsoft);
 216         CHN_UNLOCK(parent);
 217         CHN_LOCK(channel);
 218         return speed;
 219 }
 220
 221 static int
 222 vchan_setblocksize(kobj_t obj, void *data, u_int32_t blocksize)
 223 {
 224         struct vchinfo *ch = data;
 225         struct pcm_channel *channel = ch->channel;
 226         struct pcm_channel *parent = ch->parent;
 227         /* struct pcm_channel *channel = ch->channel; */
 228         int prate, crate;
 229
 230         ch->blksz = blocksize;
 231         /* CHN_UNLOCK(channel); */
 232         sndbuf_setblksz(channel->bufhard, blocksize);
 233         chn_notify(parent, CHN_N_BLOCKSIZE);
 234         CHN_LOCK(parent);
 235         /* CHN_LOCK(channel); */
 236
 237         crate = ch->spd * ch->bps;
 238         prate = sndbuf_getspd(parent->bufsoft) * sndbuf_getbps(parent->bufsoft);
 239         blocksize = sndbuf_getblksz(parent->bufsoft);
 240         CHN_UNLOCK(parent);
 241         blocksize *= prate;
 242         blocksize /= crate;
 243
 244         return blocksize;
 245 }
 246
 247 static int
 248 vchan_trigger(kobj_t obj, void *data, int go)
 249 {
 250         struct vchinfo *ch = data;
 251         struct pcm_channel *parent = ch->parent;
 252         struct pcm_channel *channel = ch->channel;
 253
 254         if (go == PCMTRIG_EMLDMAWR || go == PCMTRIG_EMLDMARD)
 255                 return 0;
 256
 257         ch->run = (go == PCMTRIG_START)? 1 : 0;
 258         CHN_UNLOCK(channel);
 259         chn_notify(parent, CHN_N_TRIGGER);
 260         CHN_LOCK(channel);
 261
 262         return 0;
 263 }
 264
 265 static struct pcmchan_caps *
 266 vchan_getcaps(kobj_t obj, void *data)
 267 {
 268         struct vchinfo *ch = data;
 269
 270         ch->caps.minspeed = sndbuf_getspd(ch->parent->bufsoft);
 271         ch->caps.maxspeed = ch->caps.minspeed;
 272         ch->caps.fmtlist = vchan_fmt;
 273         ch->caps.caps = 0;
 274
 275         return &ch->caps;
 276 }
 277
 278 static kobj_method_t vchan_methods[] = {
 279         KOBJMETHOD(channel_init,                vchan_init),
 280         KOBJMETHOD(channel_free,                vchan_free),
 281         KOBJMETHOD(channel_setformat,           vchan_setformat),
 282         KOBJMETHOD(channel_setspeed,            vchan_setspeed),
 283         KOBJMETHOD(channel_setblocksize,        vchan_setblocksize),
 284         KOBJMETHOD(channel_trigger,             vchan_trigger),
 285         KOBJMETHOD(channel_getcaps,             vchan_getcaps),
 286         { 0, 0 }
 287 };
 288 CHANNEL_DECLARE(vchan);
 289
 290 #if 0
 291 /*
 292  * On the fly vchan rate settings
 293  */
 294 #ifdef SND_DYNSYSCTL
 295 static int
 296 sysctl_hw_snd_vchanrate(SYSCTL_HANDLER_ARGS)
 297 {
 298         struct snddev_info *d;
 299         struct snddev_channel *sce;
 300         struct pcm_channel *c, *ch = NULL, *fake;
 301         struct pcmchan_caps *caps;
 302         int err = 0;
 303         int newspd = 0;
 304
 305         d = oidp->oid_arg1;
 306         if (!(d->flags & SD_F_AUTOVCHAN) || d->vchancount < 1)
 307                 return EINVAL;
 308         if (pcm_inprog(d, 1) != 1 && req->newptr != NULL) {
 309                 pcm_inprog(d, -1);
 310                 return EINPROGRESS;
 311         }
 312         SLIST_FOREACH(sce, &d->channels, link) {
 313                 c = sce->channel;
 314                 CHN_LOCK(c);
 315                 if (c->direction == PCMDIR_PLAY) {
 316                         if (c->flags & CHN_F_VIRTUAL) {
 317                                 /* Sanity check */
 318                                 if (ch != NULL && ch != c->parentchannel) {
 319                                         CHN_UNLOCK(c);
 320                                         pcm_inprog(d, -1);
 321                                         return EINVAL;
 322                                 }
 323                                 if (req->newptr != NULL &&
 324                                                 (c->flags & CHN_F_BUSY)) {
 325                                         CHN_UNLOCK(c);
 326                                         pcm_inprog(d, -1);
 327                                         return EBUSY;
 328                                 }
 329                         } else if (c->flags & CHN_F_HAS_VCHAN) {
 330                                 /* No way!! */
 331                                 if (ch != NULL) {
 332                                         CHN_UNLOCK(c);
 333                                         pcm_inprog(d, -1);
 334                                         return EINVAL;
 335                                 }
 336                                 ch = c;
 337                                 newspd = ch->speed;
 338                         }
 339                 }
 340                 CHN_UNLOCK(c);
 341         }
 342         if (ch == NULL) {
 343                 pcm_inprog(d, -1);
 344                 return EINVAL;
 345         }
 346         err = sysctl_handle_int(oidp, &newspd, sizeof(newspd), req);
 347         if (err == 0 && req->newptr != NULL) {
 348                 if (newspd < 1 || newspd < feeder_rate_ratemin ||
 349                                 newspd > feeder_rate_ratemax) {
 350                         pcm_inprog(d, -1);
 351                         return EINVAL;
 352                 }
 353                 CHN_LOCK(ch);
 354                 caps = chn_getcaps(ch);
 355                 if (caps == NULL || newspd < caps->minspeed ||
 356                                 newspd > caps->maxspeed) {
 357                         CHN_UNLOCK(ch);
 358                         pcm_inprog(d, -1);
 359                         return EINVAL;
 360                 }
 361                 if (newspd != ch->speed) {
 362                         err = chn_setspeed(ch, newspd);
 363                         /*
 364                          * Try to avoid FEEDER_RATE on parent channel if the
 365                          * requested value is not supported by the hardware.
 366                          */
 367                         if (!err && (ch->feederflags & (1 << FEEDER_RATE))) {
 368                                 newspd = sndbuf_getspd(ch->bufhard);
 369                                 err = chn_setspeed(ch, newspd);
 370                         }
 371                         CHN_UNLOCK(ch);
 372                         if (err == 0) {
 373                                 fake = pcm_getfakechan(d);
 374                                 if (fake != NULL) {
 375                                         CHN_LOCK(fake);
 376                                         fake->speed = newspd;
 377                                         CHN_UNLOCK(fake);
 378                                 }
 379                         }
 380                 } else
 381                         CHN_UNLOCK(ch);
 382         }
 383         pcm_inprog(d, -1);
 384         return err;
 385 }
 386 #endif
 387 #endif
 388
 389 /* virtual channel interface */
 390
 391 int
 392 vchan_create(struct pcm_channel *parent)
 393 {
 394         struct snddev_info *d = parent->parentsnddev;
 395         struct pcmchan_children *pce;
 396         struct pcm_channel *child, *fake;
 397         struct pcmchan_caps *parent_caps;
 398         int err, first, speed = 0;
 399
 400         if (!(parent->flags & CHN_F_BUSY))
 401                 return EBUSY;
 402
 403
 404         CHN_UNLOCK(parent);
 405
 406         pce = kmalloc(sizeof(*pce), M_DEVBUF, M_WAITOK | M_ZERO);
 407
 408         /* create a new playback channel */
 409         child = pcm_chn_create(d, parent, &vchan_class, PCMDIR_VIRTUAL, parent);
 410         if (!child) {
 411                 kfree(pce, M_DEVBUF);
 412                 CHN_LOCK(parent);
 413                 return ENODEV;
 414         }
 415         pce->channel = child;
 416
 417         /* add us to our grandparent's channel list */
 418         /*
 419          * XXX maybe we shouldn't always add the dev_t
 420          */
 421         err = pcm_chn_add(d, child);
 422         if (err) {
 423                 pcm_chn_destroy(child);
 424                 kfree(pce, M_DEVBUF);
 425                 CHN_LOCK(parent);
 426                 return err;
 427         }
 428
 429         CHN_LOCK(parent);
 430         /* add us to our parent channel's children */
 431         first = SLIST_EMPTY(&parent->children);
 432         SLIST_INSERT_HEAD(&parent->children, pce, link);
 433         parent->flags |= CHN_F_HAS_VCHAN;
 434
 435         if (first) {
 436                 parent_caps = chn_getcaps(parent);
 437                 if (parent_caps == NULL)
 438                         err = EINVAL;
 439
 440                 if (!err)
 441                         err = chn_reset(parent, AFMT_STEREO | AFMT_S16_LE);
 442
 443                 if (!err) {
 444                         fake = pcm_getfakechan(d);
 445                         if (fake != NULL) {
 446                                 /*
 447                                  * Avoid querying kernel hint, use saved value
 448                                  * from fake channel.
 449                                  */
 450                                 CHN_UNLOCK(parent);
 451                                 CHN_LOCK(fake);
 452                                 speed = fake->speed;
 453                                 CHN_UNLOCK(fake);
 454                                 CHN_LOCK(parent);
 455                         }
 456
 457                         /*
 458                          * This is very sad. Few soundcards advertised as being
 459                          * able to do (insanely) higher/lower speed, but in
 460                          * reality, they simply can't. At least, we give user chance
 461                          * to set sane value via kernel hints or sysctl.
 462                          */
 463                         if (speed < 1) {
 464                                 int r;
 465                                 CHN_UNLOCK(parent);
 466                                 r = resource_int_value(device_get_name(parent->dev),
 467                                                         device_get_unit(parent->dev),
 468                                                                 "vchanrate", &speed);
 469                                 CHN_LOCK(parent);
 470                                 if (r != 0) {
 471                                         /*
 472                                          * Workaround for sb16 running
 473                                          * poorly at 45k / 49k.
 474                                          */
 475                                         switch (parent_caps->maxspeed) {
 476                                         case 45000:
 477                                         case 49000:
 478                                                 speed = 44100;
 479                                                 break;
 480                                         default:
 481                                                 speed = VCHAN_DEFAULT_SPEED;
 482                                                 break;
 483                                         }
 484                                 }
 485                         }
 486
 487                         /*
 488                          * Limit speed based on driver caps.
 489                          * This is supposed to help fixed rate, non-VRA
 490                          * AC97 cards, but.. (see below)
 491                          */
 492                         if (speed < parent_caps->minspeed)
 493                                 speed = parent_caps->minspeed;
 494                         if (speed > parent_caps->maxspeed)
 495                                 speed = parent_caps->maxspeed;
 496
 497                         /*
 498                          * We still need to limit the speed between
 499                          * feeder_rate_ratemin <-> feeder_rate_ratemax. This is
 500                          * just an escape goat if all of the above failed
 501                          * miserably.
 502                          */
 503                         if (speed < feeder_rate_ratemin)
 504                                 speed = feeder_rate_ratemin;
 505                         if (speed > feeder_rate_ratemax)
 506                                 speed = feeder_rate_ratemax;
 507
 508                         err = chn_setspeed(parent, speed);
 509                         /*
 510                          * Try to avoid FEEDER_RATE on parent channel if the
 511                          * requested value is not supported by the hardware.
 512                          */
 513                         if (!err && (parent->feederflags & (1 << FEEDER_RATE))) {
 514                                 speed = sndbuf_getspd(parent->bufhard);
 515                                 err = chn_setspeed(parent, speed);
 516                         }
 517
 518                         if (!err && fake != NULL) {
 519                                 /*
 520                                  * Save new value to fake channel.
 521                                  */
 522                                 CHN_UNLOCK(parent);
 523                                 CHN_LOCK(fake);
 524                                 fake->speed = speed;
 525                                 CHN_UNLOCK(fake);
 526                                 CHN_LOCK(parent);
 527                         }
 528                 }
 529
 530                 if (err) {
 531                         SLIST_REMOVE(&parent->children, pce, pcmchan_children, link);
 532                         parent->flags &= ~CHN_F_HAS_VCHAN;
 533                         CHN_UNLOCK(parent);
 534                         kfree(pce, M_DEVBUF);
 535                         if (pcm_chn_remove(d, child) == 0)
 536                                 pcm_chn_destroy(child);
 537                         CHN_LOCK(parent);
 538                         return err;
 539                 }
 540         }
 541
 542         return 0;
 543 }
 544
 545 int
 546 vchan_destroy(struct pcm_channel *c)
 547 {
 548         struct pcm_channel *parent = c->parentchannel;
 549         struct snddev_info *d = parent->parentsnddev;
 550         struct pcmchan_children *pce;
 551         struct snddev_channel *sce;
 552         uint32_t spd;
 553         int err;
 554
 555         CHN_LOCK(parent);
 556         if (!(parent->flags & CHN_F_BUSY)) {
 557                 CHN_UNLOCK(parent);
 558                 return EBUSY;
 559         }
 560         if (SLIST_EMPTY(&parent->children)) {
 561                 CHN_UNLOCK(parent);
 562                 return EINVAL;
 563         }
 564
 565         /* remove us from our parent's children list */
 566         SLIST_FOREACH(pce, &parent->children, link) {
 567                 if (pce->channel == c)
 568                         goto gotch;
 569         }
 570         CHN_UNLOCK(parent);
 571         return EINVAL;
 572 gotch:
 573         SLIST_FOREACH(sce, &d->channels, link) {
 574                 if (sce->channel == c) {
 575                         if (sce->dsp_devt) {
 576                                 destroy_dev(sce->dsp_devt);
 577                                 sce->dsp_devt = NULL;
 578                         }
 579                         if (sce->dspW_devt) {
 580                                 destroy_dev(sce->dspW_devt);
 581                                 sce->dspW_devt = NULL;
 582                         }
 583                         if (sce->audio_devt) {
 584                                 destroy_dev(sce->audio_devt);
 585                                 sce->audio_devt = NULL;
 586                         }
 587                         if (sce->dspr_devt) {
 588                                 destroy_dev(sce->dspr_devt);
 589                                 sce->dspr_devt = NULL;
 590                         }
 591                         d->devcount--;
 592                         break;
 593                 }
 594         }
 595         SLIST_REMOVE(&parent->children, pce, pcmchan_children, link);
 596         kfree(pce, M_DEVBUF);
 597
 598         if (SLIST_EMPTY(&parent->children)) {
 599                 parent->flags &= ~(CHN_F_BUSY | CHN_F_HAS_VCHAN);
 600                 spd = parent->speed;
 601                 if (chn_reset(parent, parent->format) == 0)
 602                         chn_setspeed(parent, spd);
 603         }
 604
 605         /* remove us from our grandparent's channel list */
 606         err = pcm_chn_remove(d, c);
 607
 608         CHN_UNLOCK(parent);
 609         /* destroy ourselves */
 610         if (!err)
 611                 err = pcm_chn_destroy(c);
 612
 613         return err;
 614 }
 615
 616 int
 617 vchan_initsys(device_t dev)
 618 {
 619 #ifdef SND_DYNSYSCTL
 620         struct snddev_info *d;
 621
 622         d = device_get_softc(dev);
 623         SYSCTL_ADD_PROC(snd_sysctl_tree(dev), SYSCTL_CHILDREN(snd_sysctl_tree_top(dev)),
 624             OID_AUTO, "vchans", CTLTYPE_INT | CTLFLAG_RW, d, sizeof(d),
 625             sysctl_hw_snd_vchans, "I", "");
 626 #if 0
 627         SYSCTL_ADD_PROC(snd_sysctl_tree(dev), SYSCTL_CHILDREN(snd_sysctl_tree_top(dev)),
 628             OID_AUTO, "vchanrate", CTLTYPE_INT | CTLFLAG_RW, d, sizeof(d),
 629             sysctl_hw_snd_vchanrate, "I", "");
 630 #endif
 631 #endif
 632
 633         return 0;
 634 }