sound/usb/pcm.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  */
   4
   5 #include <linux/init.h>
   6 #include <linux/slab.h>
   7 #include <linux/bitrev.h>
   8 #include <linux/ratelimit.h>
   9 #include <linux/usb.h>
  10 #include <linux/usb/audio.h>
  11 #include <linux/usb/audio-v2.h>
  12
  13 #include <sound/core.h>
  14 #include <sound/pcm.h>
  15 #include <sound/pcm_params.h>
  16
  17 #include "usbaudio.h"
  18 #include "card.h"
  19 #include "quirks.h"
  20 #include "debug.h"
  21 #include "endpoint.h"
  22 #include "helper.h"
  23 #include "pcm.h"
  24 #include "clock.h"
  25 #include "power.h"
  26 #include "media.h"
  27
  28 #define SUBSTREAM_FLAG_DATA_EP_STARTED  0
  29 #define SUBSTREAM_FLAG_SYNC_EP_STARTED  1
  30
  31 /* return the estimated delay based on USB frame counters */
  32 snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,
  33                                     unsigned int rate)
  34 {
  35         int current_frame_number;
  36         int frame_diff;
  37         int est_delay;
  38
  39         if (!subs->last_delay)
  40                 return 0; /* short path */
  41
  42         current_frame_number = usb_get_current_frame_number(subs->dev);
  43         /*
  44          * HCD implementations use different widths, use lower 8 bits.
  45          * The delay will be managed up to 256ms, which is more than
  46          * enough
  47          */
  48         frame_diff = (current_frame_number - subs->last_frame_number) & 0xff;
  49
  50         /* Approximation based on number of samples per USB frame (ms),
  51            some truncation for 44.1 but the estimate is good enough */
  52         est_delay =  frame_diff * rate / 1000;
  53         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
  54                 est_delay = subs->last_delay - est_delay;
  55         else
  56                 est_delay = subs->last_delay + est_delay;
  57
  58         if (est_delay < 0)
  59                 est_delay = 0;
  60         return est_delay;
  61 }
  62
  63 /*
  64  * return the current pcm pointer.  just based on the hwptr_done value.
  65  */
  66 static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream)
  67 {
  68         struct snd_usb_substream *subs = substream->runtime->private_data;
  69         unsigned int hwptr_done;
  70
  71         if (atomic_read(&subs->stream->chip->shutdown))
  72                 return SNDRV_PCM_POS_XRUN;
  73         spin_lock(&subs->lock);
  74         hwptr_done = subs->hwptr_done;
  75         substream->runtime->delay = snd_usb_pcm_delay(subs,
  76                                                 substream->runtime->rate);
  77         spin_unlock(&subs->lock);
  78         return hwptr_done / (substream->runtime->frame_bits >> 3);
  79 }
  80
  81 /*
  82  * find a matching audio format
  83  */
  84 static struct audioformat *find_format(struct snd_usb_substream *subs)
  85 {
  86         struct audioformat *fp;
  87         struct audioformat *found = NULL;
  88         int cur_attr = 0, attr;
  89
  90         list_for_each_entry(fp, &subs->fmt_list, list) {
  91                 if (!(fp->formats & pcm_format_to_bits(subs->pcm_format)))
  92                         continue;
  93                 if (fp->channels != subs->channels)
  94                         continue;
  95                 if (subs->cur_rate < fp->rate_min ||
  96                     subs->cur_rate > fp->rate_max)
  97                         continue;
  98                 if (! (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
  99                         unsigned int i;
 100                         for (i = 0; i < fp->nr_rates; i++)
 101                                 if (fp->rate_table[i] == subs->cur_rate)
 102                                         break;
 103                         if (i >= fp->nr_rates)
 104                                 continue;
 105                 }
 106                 attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
 107                 if (! found) {
 108                         found = fp;
 109                         cur_attr = attr;
 110                         continue;
 111                 }
 112                 /* avoid async out and adaptive in if the other method
 113                  * supports the same format.
 114                  * this is a workaround for the case like
 115                  * M-audio audiophile USB.
 116                  */
 117                 if (attr != cur_attr) {
 118                         if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
 119                              subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
 120                             (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
 121                              subs->direction == SNDRV_PCM_STREAM_CAPTURE))
 122                                 continue;
 123                         if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
 124                              subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
 125                             (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
 126                              subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
 127                                 found = fp;
 128                                 cur_attr = attr;
 129                                 continue;
 130                         }
 131                 }
 132                 /* find the format with the largest max. packet size */
 133                 if (fp->maxpacksize > found->maxpacksize) {
 134                         found = fp;
 135                         cur_attr = attr;
 136                 }
 137         }
 138         return found;
 139 }
 140
 141 static int init_pitch_v1(struct snd_usb_audio *chip, int iface,
 142                          struct usb_host_interface *alts,
 143                          struct audioformat *fmt)
 144 {
 145         struct usb_device *dev = chip->dev;
 146         unsigned int ep;
 147         unsigned char data[1];
 148         int err;
 149
 150         if (get_iface_desc(alts)->bNumEndpoints < 1)
 151                 return -EINVAL;
 152         ep = get_endpoint(alts, 0)->bEndpointAddress;
 153
 154         data[0] = 1;
 155         err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
 156                               USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
 157                               UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
 158                               data, sizeof(data));
 159         if (err < 0) {
 160                 usb_audio_err(chip, "%d:%d: cannot set enable PITCH\n",
 161                               iface, ep);
 162                 return err;
 163         }
 164
 165         return 0;
 166 }
 167
 168 static int init_pitch_v2(struct snd_usb_audio *chip, int iface,
 169                          struct usb_host_interface *alts,
 170                          struct audioformat *fmt)
 171 {
 172         struct usb_device *dev = chip->dev;
 173         unsigned char data[1];
 174         int err;
 175
 176         data[0] = 1;
 177         err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
 178                               USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
 179                               UAC2_EP_CS_PITCH << 8, 0,
 180                               data, sizeof(data));
 181         if (err < 0) {
 182                 usb_audio_err(chip, "%d:%d: cannot set enable PITCH (v2)\n",
 183                               iface, fmt->altsetting);
 184                 return err;
 185         }
 186
 187         return 0;
 188 }
 189
 190 /*
 191  * initialize the pitch control and sample rate
 192  */
 193 int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
 194                        struct usb_host_interface *alts,
 195                        struct audioformat *fmt)
 196 {
 197         /* if endpoint doesn't have pitch control, bail out */
 198         if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
 199                 return 0;
 200
 201         switch (fmt->protocol) {
 202         case UAC_VERSION_1:
 203         default:
 204                 return init_pitch_v1(chip, iface, alts, fmt);
 205
 206         case UAC_VERSION_2:
 207                 return init_pitch_v2(chip, iface, alts, fmt);
 208         }
 209 }
 210
 211 static int start_endpoints(struct snd_usb_substream *subs)
 212 {
 213         int err;
 214
 215         if (!subs->data_endpoint)
 216                 return -EINVAL;
 217
 218         if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
 219                 struct snd_usb_endpoint *ep = subs->data_endpoint;
 220
 221                 dev_dbg(&subs->dev->dev, "Starting data EP @%p\n", ep);
 222
 223                 ep->data_subs = subs;
 224                 err = snd_usb_endpoint_start(ep);
 225                 if (err < 0) {
 226                         clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
 227                         return err;
 228                 }
 229         }
 230
 231         if (subs->sync_endpoint &&
 232             !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
 233                 struct snd_usb_endpoint *ep = subs->sync_endpoint;
 234
 235                 if (subs->data_endpoint->iface != subs->sync_endpoint->iface ||
 236                     subs->data_endpoint->altsetting != subs->sync_endpoint->altsetting) {
 237                         err = usb_set_interface(subs->dev,
 238                                                 subs->sync_endpoint->iface,
 239                                                 subs->sync_endpoint->altsetting);
 240                         if (err < 0) {
 241                                 clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
 242                                 dev_err(&subs->dev->dev,
 243                                            "%d:%d: cannot set interface (%d)\n",
 244                                            subs->sync_endpoint->iface,
 245                                            subs->sync_endpoint->altsetting, err);
 246                                 return -EIO;
 247                         }
 248                 }
 249
 250                 dev_dbg(&subs->dev->dev, "Starting sync EP @%p\n", ep);
 251
 252                 ep->sync_slave = subs->data_endpoint;
 253                 err = snd_usb_endpoint_start(ep);
 254                 if (err < 0) {
 255                         clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
 256                         return err;
 257                 }
 258         }
 259
 260         return 0;
 261 }
 262
 263 static void stop_endpoints(struct snd_usb_substream *subs, bool wait)
 264 {
 265         if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags))
 266                 snd_usb_endpoint_stop(subs->sync_endpoint);
 267
 268         if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags))
 269                 snd_usb_endpoint_stop(subs->data_endpoint);
 270
 271         if (wait) {
 272                 snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
 273                 snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
 274         }
 275 }
 276
 277 static int search_roland_implicit_fb(struct usb_device *dev, int ifnum,
 278                                      unsigned int altsetting,
 279                                      struct usb_host_interface **alts,
 280                                      unsigned int *ep)
 281 {
 282         struct usb_interface *iface;
 283         struct usb_interface_descriptor *altsd;
 284         struct usb_endpoint_descriptor *epd;
 285
 286         iface = usb_ifnum_to_if(dev, ifnum);
 287         if (!iface || iface->num_altsetting < altsetting + 1)
 288                 return -ENOENT;
 289         *alts = &iface->altsetting[altsetting];
 290         altsd = get_iface_desc(*alts);
 291         if (altsd->bAlternateSetting != altsetting ||
 292             altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC ||
 293             (altsd->bInterfaceSubClass != 2 &&
 294              altsd->bInterfaceProtocol != 2   ) ||
 295             altsd->bNumEndpoints < 1)
 296                 return -ENOENT;
 297         epd = get_endpoint(*alts, 0);
 298         if (!usb_endpoint_is_isoc_in(epd) ||
 299             (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) !=
 300                                         USB_ENDPOINT_USAGE_IMPLICIT_FB)
 301                 return -ENOENT;
 302         *ep = epd->bEndpointAddress;
 303         return 0;
 304 }
 305
 306 /* Setup an implicit feedback endpoint from a quirk. Returns 0 if no quirk
 307  * applies. Returns 1 if a quirk was found.
 308  */
 309 static int set_sync_ep_implicit_fb_quirk(struct snd_usb_substream *subs,
 310                                          struct usb_device *dev,
 311                                          struct usb_interface_descriptor *altsd,
 312                                          unsigned int attr)
 313 {
 314         struct usb_host_interface *alts;
 315         struct usb_interface *iface;
 316         unsigned int ep;
 317         unsigned int ifnum;
 318
 319         /* Implicit feedback sync EPs consumers are always playback EPs */
 320         if (subs->direction != SNDRV_PCM_STREAM_PLAYBACK)
 321                 return 0;
 322
 323         switch (subs->stream->chip->usb_id) {
 324         case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
 325         case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
 326                 ep = 0x81;
 327                 ifnum = 3;
 328                 goto add_sync_ep_from_ifnum;
 329         case USB_ID(0x0763, 0x2080): /* M-Audio FastTrack Ultra */
 330         case USB_ID(0x0763, 0x2081):
 331                 ep = 0x81;
 332                 ifnum = 2;
 333                 goto add_sync_ep_from_ifnum;
 334         case USB_ID(0x2466, 0x8003): /* Fractal Audio Axe-Fx II */
 335                 ep = 0x86;
 336                 ifnum = 2;
 337                 goto add_sync_ep_from_ifnum;
 338         case USB_ID(0x2466, 0x8010): /* Fractal Audio Axe-Fx III */
 339                 ep = 0x81;
 340                 ifnum = 2;
 341                 goto add_sync_ep_from_ifnum;
 342         case USB_ID(0x1397, 0x0001): /* Behringer UFX1604 */
 343         case USB_ID(0x1397, 0x0002): /* Behringer UFX1204 */
 344                 ep = 0x81;
 345                 ifnum = 1;
 346                 goto add_sync_ep_from_ifnum;
 347         case USB_ID(0x07fd, 0x0004): /* MOTU MicroBook II */
 348                 ep = 0x84;
 349                 ifnum = 0;
 350                 goto add_sync_ep_from_ifnum;
 351         case USB_ID(0x0582, 0x01d8): /* BOSS Katana */
 352                 /* BOSS Katana amplifiers do not need quirks */
 353                 return 0;
 354         }
 355
 356         if (attr == USB_ENDPOINT_SYNC_ASYNC &&
 357             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 358             altsd->bInterfaceProtocol == 2 &&
 359             altsd->bNumEndpoints == 1 &&
 360             USB_ID_VENDOR(subs->stream->chip->usb_id) == 0x0582 /* Roland */ &&
 361             search_roland_implicit_fb(dev, altsd->bInterfaceNumber + 1,
 362                                       altsd->bAlternateSetting,
 363                                       &alts, &ep) >= 0) {
 364                 goto add_sync_ep;
 365         }
 366
 367         /* No quirk */
 368         return 0;
 369
 370 add_sync_ep_from_ifnum:
 371         iface = usb_ifnum_to_if(dev, ifnum);
 372
 373         if (!iface || iface->num_altsetting == 0)
 374                 return -EINVAL;
 375
 376         alts = &iface->altsetting[1];
 377
 378 add_sync_ep:
 379         subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
 380                                                    alts, ep, !subs->direction,
 381                                                    SND_USB_ENDPOINT_TYPE_DATA);
 382         if (!subs->sync_endpoint)
 383                 return -EINVAL;
 384
 385         subs->data_endpoint->sync_master = subs->sync_endpoint;
 386
 387         return 1;
 388 }
 389
 390 static int set_sync_endpoint(struct snd_usb_substream *subs,
 391                              struct audioformat *fmt,
 392                              struct usb_device *dev,
 393                              struct usb_host_interface *alts,
 394                              struct usb_interface_descriptor *altsd)
 395 {
 396         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
 397         unsigned int ep, attr;
 398         bool implicit_fb;
 399         int err;
 400
 401         /* we need a sync pipe in async OUT or adaptive IN mode */
 402         /* check the number of EP, since some devices have broken
 403          * descriptors which fool us.  if it has only one EP,
 404          * assume it as adaptive-out or sync-in.
 405          */
 406         attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
 407
 408         if ((is_playback && (attr != USB_ENDPOINT_SYNC_ASYNC)) ||
 409                 (!is_playback && (attr != USB_ENDPOINT_SYNC_ADAPTIVE))) {
 410
 411                 /*
 412                  * In these modes the notion of sync_endpoint is irrelevant.
 413                  * Reset pointers to avoid using stale data from previously
 414                  * used settings, e.g. when configuration and endpoints were
 415                  * changed
 416                  */
 417
 418                 subs->sync_endpoint = NULL;
 419                 subs->data_endpoint->sync_master = NULL;
 420         }
 421
 422         err = set_sync_ep_implicit_fb_quirk(subs, dev, altsd, attr);
 423         if (err < 0)
 424                 return err;
 425
 426         /* endpoint set by quirk */
 427         if (err > 0)
 428                 return 0;
 429
 430         if (altsd->bNumEndpoints < 2)
 431                 return 0;
 432
 433         if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
 434                              attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
 435             (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
 436                 return 0;
 437
 438         /*
 439          * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
 440          * if we don't find a sync endpoint, as on M-Audio Transit. In case of
 441          * error fall back to SYNC mode and don't create sync endpoint
 442          */
 443
 444         /* check sync-pipe endpoint */
 445         /* ... and check descriptor size before accessing bSynchAddress
 446            because there is a version of the SB Audigy 2 NX firmware lacking
 447            the audio fields in the endpoint descriptors */
 448         if ((get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
 449             (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
 450              get_endpoint(alts, 1)->bSynchAddress != 0)) {
 451                 dev_err(&dev->dev,
 452                         "%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
 453                            fmt->iface, fmt->altsetting,
 454                            get_endpoint(alts, 1)->bmAttributes,
 455                            get_endpoint(alts, 1)->bLength,
 456                            get_endpoint(alts, 1)->bSynchAddress);
 457                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
 458                         return 0;
 459                 return -EINVAL;
 460         }
 461         ep = get_endpoint(alts, 1)->bEndpointAddress;
 462         if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
 463             get_endpoint(alts, 0)->bSynchAddress != 0 &&
 464             ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
 465              (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
 466                 dev_err(&dev->dev,
 467                         "%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
 468                            fmt->iface, fmt->altsetting,
 469                            is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
 470                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
 471                         return 0;
 472                 return -EINVAL;
 473         }
 474
 475         implicit_fb = (get_endpoint(alts, 1)->bmAttributes & USB_ENDPOINT_USAGE_MASK)
 476                         == USB_ENDPOINT_USAGE_IMPLICIT_FB;
 477
 478         subs->sync_endpoint = snd_usb_add_endpoint(subs->stream->chip,
 479                                                    alts, ep, !subs->direction,
 480                                                    implicit_fb ?
 481                                                         SND_USB_ENDPOINT_TYPE_DATA :
 482                                                         SND_USB_ENDPOINT_TYPE_SYNC);
 483         if (!subs->sync_endpoint) {
 484                 if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
 485                         return 0;
 486                 return -EINVAL;
 487         }
 488
 489         subs->data_endpoint->sync_master = subs->sync_endpoint;
 490
 491         return 0;
 492 }
 493
 494 /*
 495  * find a matching format and set up the interface
 496  */
 497 static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
 498 {
 499         struct usb_device *dev = subs->dev;
 500         struct usb_host_interface *alts;
 501         struct usb_interface_descriptor *altsd;
 502         struct usb_interface *iface;
 503         int err;
 504
 505         iface = usb_ifnum_to_if(dev, fmt->iface);
 506         if (WARN_ON(!iface))
 507                 return -EINVAL;
 508         alts = usb_altnum_to_altsetting(iface, fmt->altsetting);
 509         altsd = get_iface_desc(alts);
 510         if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting))
 511                 return -EINVAL;
 512
 513         if (fmt == subs->cur_audiofmt)
 514                 return 0;
 515
 516         /* close the old interface */
 517         if (subs->interface >= 0 && subs->interface != fmt->iface) {
 518                 if (!subs->stream->chip->keep_iface) {
 519                         err = usb_set_interface(subs->dev, subs->interface, 0);
 520                         if (err < 0) {
 521                                 dev_err(&dev->dev,
 522                                         "%d:%d: return to setting 0 failed (%d)\n",
 523                                         fmt->iface, fmt->altsetting, err);
 524                                 return -EIO;
 525                         }
 526                 }
 527                 subs->interface = -1;
 528                 subs->altset_idx = 0;
 529         }
 530
 531         /* set interface */
 532         if (iface->cur_altsetting != alts) {
 533                 err = snd_usb_select_mode_quirk(subs, fmt);
 534                 if (err < 0)
 535                         return -EIO;
 536
 537                 err = usb_set_interface(dev, fmt->iface, fmt->altsetting);
 538                 if (err < 0) {
 539                         dev_err(&dev->dev,
 540                                 "%d:%d: usb_set_interface failed (%d)\n",
 541                                 fmt->iface, fmt->altsetting, err);
 542                         return -EIO;
 543                 }
 544                 dev_dbg(&dev->dev, "setting usb interface %d:%d\n",
 545                         fmt->iface, fmt->altsetting);
 546                 snd_usb_set_interface_quirk(dev);
 547         }
 548
 549         subs->interface = fmt->iface;
 550         subs->altset_idx = fmt->altset_idx;
 551         subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip,
 552                                                    alts, fmt->endpoint, subs->direction,
 553                                                    SND_USB_ENDPOINT_TYPE_DATA);
 554
 555         if (!subs->data_endpoint)
 556                 return -EINVAL;
 557
 558         err = set_sync_endpoint(subs, fmt, dev, alts, altsd);
 559         if (err < 0)
 560                 return err;
 561
 562         err = snd_usb_init_pitch(subs->stream->chip, fmt->iface, alts, fmt);
 563         if (err < 0)
 564                 return err;
 565
 566         subs->cur_audiofmt = fmt;
 567
 568         snd_usb_set_format_quirk(subs, fmt);
 569
 570         return 0;
 571 }
 572
 573 /*
 574  * Return the score of matching two audioformats.
 575  * Veto the audioformat if:
 576  * - It has no channels for some reason.
 577  * - Requested PCM format is not supported.
 578  * - Requested sample rate is not supported.
 579  */
 580 static int match_endpoint_audioformats(struct snd_usb_substream *subs,
 581                                        struct audioformat *fp,
 582                                        struct audioformat *match, int rate,
 583                                        snd_pcm_format_t pcm_format)
 584 {
 585         int i;
 586         int score = 0;
 587
 588         if (fp->channels < 1) {
 589                 dev_dbg(&subs->dev->dev,
 590                         "%s: (fmt @%p) no channels\n", __func__, fp);
 591                 return 0;
 592         }
 593
 594         if (!(fp->formats & pcm_format_to_bits(pcm_format))) {
 595                 dev_dbg(&subs->dev->dev,
 596                         "%s: (fmt @%p) no match for format %d\n", __func__,
 597                         fp, pcm_format);
 598                 return 0;
 599         }
 600
 601         for (i = 0; i < fp->nr_rates; i++) {
 602                 if (fp->rate_table[i] == rate) {
 603                         score++;
 604                         break;
 605                 }
 606         }
 607         if (!score) {
 608                 dev_dbg(&subs->dev->dev,
 609                         "%s: (fmt @%p) no match for rate %d\n", __func__,
 610                         fp, rate);
 611                 return 0;
 612         }
 613
 614         if (fp->channels == match->channels)
 615                 score++;
 616
 617         dev_dbg(&subs->dev->dev,
 618                 "%s: (fmt @%p) score %d\n", __func__, fp, score);
 619
 620         return score;
 621 }
 622
 623 /*
 624  * Configure the sync ep using the rate and pcm format of the data ep.
 625  */
 626 static int configure_sync_endpoint(struct snd_usb_substream *subs)
 627 {
 628         int ret;
 629         struct audioformat *fp;
 630         struct audioformat *sync_fp = NULL;
 631         int cur_score = 0;
 632         int sync_period_bytes = subs->period_bytes;
 633         struct snd_usb_substream *sync_subs =
 634                 &subs->stream->substream[subs->direction ^ 1];
 635
 636         if (subs->sync_endpoint->type != SND_USB_ENDPOINT_TYPE_DATA ||
 637             !subs->stream)
 638                 return snd_usb_endpoint_set_params(subs->sync_endpoint,
 639                                                    subs->pcm_format,
 640                                                    subs->channels,
 641                                                    subs->period_bytes,
 642                                                    0, 0,
 643                                                    subs->cur_rate,
 644                                                    subs->cur_audiofmt,
 645                                                    NULL);
 646
 647         /* Try to find the best matching audioformat. */
 648         list_for_each_entry(fp, &sync_subs->fmt_list, list) {
 649                 int score = match_endpoint_audioformats(subs,
 650                                                         fp, subs->cur_audiofmt,
 651                         subs->cur_rate, subs->pcm_format);
 652
 653                 if (score > cur_score) {
 654                         sync_fp = fp;
 655                         cur_score = score;
 656                 }
 657         }
 658
 659         if (unlikely(sync_fp == NULL)) {
 660                 dev_err(&subs->dev->dev,
 661                         "%s: no valid audioformat for sync ep %x found\n",
 662                         __func__, sync_subs->ep_num);
 663                 return -EINVAL;
 664         }
 665
 666         /*
 667          * Recalculate the period bytes if channel number differ between
 668          * data and sync ep audioformat.
 669          */
 670         if (sync_fp->channels != subs->channels) {
 671                 sync_period_bytes = (subs->period_bytes / subs->channels) *
 672                         sync_fp->channels;
 673                 dev_dbg(&subs->dev->dev,
 674                         "%s: adjusted sync ep period bytes (%d -> %d)\n",
 675                         __func__, subs->period_bytes, sync_period_bytes);
 676         }
 677
 678         ret = snd_usb_endpoint_set_params(subs->sync_endpoint,
 679                                           subs->pcm_format,
 680                                           sync_fp->channels,
 681                                           sync_period_bytes,
 682                                           0, 0,
 683                                           subs->cur_rate,
 684                                           sync_fp,
 685                                           NULL);
 686
 687         return ret;
 688 }
 689
 690 /*
 691  * configure endpoint params
 692  *
 693  * called  during initial setup and upon resume
 694  */
 695 static int configure_endpoint(struct snd_usb_substream *subs)
 696 {
 697         int ret;
 698
 699         /* format changed */
 700         stop_endpoints(subs, true);
 701         ret = snd_usb_endpoint_set_params(subs->data_endpoint,
 702                                           subs->pcm_format,
 703                                           subs->channels,
 704                                           subs->period_bytes,
 705                                           subs->period_frames,
 706                                           subs->buffer_periods,
 707                                           subs->cur_rate,
 708                                           subs->cur_audiofmt,
 709                                           subs->sync_endpoint);
 710         if (ret < 0)
 711                 return ret;
 712
 713         if (subs->sync_endpoint)
 714                 ret = configure_sync_endpoint(subs);
 715
 716         return ret;
 717 }
 718
 719 static int snd_usb_pcm_change_state(struct snd_usb_substream *subs, int state)
 720 {
 721         int ret;
 722
 723         if (!subs->str_pd)
 724                 return 0;
 725
 726         ret = snd_usb_power_domain_set(subs->stream->chip, subs->str_pd, state);
 727         if (ret < 0) {
 728                 dev_err(&subs->dev->dev,
 729                         "Cannot change Power Domain ID: %d to state: %d. Err: %d\n",
 730                         subs->str_pd->pd_id, state, ret);
 731                 return ret;
 732         }
 733
 734         return 0;
 735 }
 736
 737 int snd_usb_pcm_suspend(struct snd_usb_stream *as)
 738 {
 739         int ret;
 740
 741         ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D2);
 742         if (ret < 0)
 743                 return ret;
 744
 745         ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D2);
 746         if (ret < 0)
 747                 return ret;
 748
 749         return 0;
 750 }
 751
 752 int snd_usb_pcm_resume(struct snd_usb_stream *as)
 753 {
 754         int ret;
 755
 756         ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D1);
 757         if (ret < 0)
 758                 return ret;
 759
 760         ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D1);
 761         if (ret < 0)
 762                 return ret;
 763
 764         return 0;
 765 }
 766
 767 /*
 768  * hw_params callback
 769  *
 770  * allocate a buffer and set the given audio format.
 771  *
 772  * so far we use a physically linear buffer although packetize transfer
 773  * doesn't need a continuous area.
 774  * if sg buffer is supported on the later version of alsa, we'll follow
 775  * that.
 776  */
 777 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
 778                              struct snd_pcm_hw_params *hw_params)
 779 {
 780         struct snd_usb_substream *subs = substream->runtime->private_data;
 781         struct audioformat *fmt;
 782         int ret;
 783
 784         ret = snd_media_start_pipeline(subs);
 785         if (ret)
 786                 return ret;
 787
 788         ret = snd_pcm_lib_malloc_pages(substream,
 789                                        params_buffer_bytes(hw_params));
 790         if (ret < 0)
 791                 goto stop_pipeline;
 792
 793         subs->pcm_format = params_format(hw_params);
 794         subs->period_bytes = params_period_bytes(hw_params);
 795         subs->period_frames = params_period_size(hw_params);
 796         subs->buffer_periods = params_periods(hw_params);
 797         subs->channels = params_channels(hw_params);
 798         subs->cur_rate = params_rate(hw_params);
 799
 800         fmt = find_format(subs);
 801         if (!fmt) {
 802                 dev_dbg(&subs->dev->dev,
 803                         "cannot set format: format = %#x, rate = %d, channels = %d\n",
 804                            subs->pcm_format, subs->cur_rate, subs->channels);
 805                 ret = -EINVAL;
 806                 goto stop_pipeline;
 807         }
 808
 809         ret = snd_usb_lock_shutdown(subs->stream->chip);
 810         if (ret < 0)
 811                 goto stop_pipeline;
 812
 813         ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
 814         if (ret < 0)
 815                 goto unlock;
 816
 817         ret = set_format(subs, fmt);
 818         if (ret < 0)
 819                 goto unlock;
 820
 821         subs->interface = fmt->iface;
 822         subs->altset_idx = fmt->altset_idx;
 823         subs->need_setup_ep = true;
 824
 825  unlock:
 826         snd_usb_unlock_shutdown(subs->stream->chip);
 827         if (ret < 0)
 828                 goto stop_pipeline;
 829         return ret;
 830
 831  stop_pipeline:
 832         snd_media_stop_pipeline(subs);
 833         return ret;
 834 }
 835
 836 /*
 837  * hw_free callback
 838  *
 839  * reset the audio format and release the buffer
 840  */
 841 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
 842 {
 843         struct snd_usb_substream *subs = substream->runtime->private_data;
 844
 845         snd_media_stop_pipeline(subs);
 846         subs->cur_audiofmt = NULL;
 847         subs->cur_rate = 0;
 848         subs->period_bytes = 0;
 849         if (!snd_usb_lock_shutdown(subs->stream->chip)) {
 850                 stop_endpoints(subs, true);
 851                 snd_usb_endpoint_deactivate(subs->sync_endpoint);
 852                 snd_usb_endpoint_deactivate(subs->data_endpoint);
 853                 snd_usb_unlock_shutdown(subs->stream->chip);
 854         }
 855
 856         return snd_pcm_lib_free_pages(substream);
 857 }
 858
 859 /*
 860  * prepare callback
 861  *
 862  * only a few subtle things...
 863  */
 864 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
 865 {
 866         struct snd_pcm_runtime *runtime = substream->runtime;
 867         struct snd_usb_substream *subs = runtime->private_data;
 868         struct usb_host_interface *alts;
 869         struct usb_interface *iface;
 870         int ret;
 871
 872         if (! subs->cur_audiofmt) {
 873                 dev_err(&subs->dev->dev, "no format is specified!\n");
 874                 return -ENXIO;
 875         }
 876
 877         ret = snd_usb_lock_shutdown(subs->stream->chip);
 878         if (ret < 0)
 879                 return ret;
 880         if (snd_BUG_ON(!subs->data_endpoint)) {
 881                 ret = -EIO;
 882                 goto unlock;
 883         }
 884
 885         snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
 886         snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
 887
 888         ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
 889         if (ret < 0)
 890                 goto unlock;
 891
 892         ret = set_format(subs, subs->cur_audiofmt);
 893         if (ret < 0)
 894                 goto unlock;
 895
 896         if (subs->need_setup_ep) {
 897
 898                 iface = usb_ifnum_to_if(subs->dev, subs->cur_audiofmt->iface);
 899                 alts = &iface->altsetting[subs->cur_audiofmt->altset_idx];
 900                 ret = snd_usb_init_sample_rate(subs->stream->chip,
 901                                                subs->cur_audiofmt->iface,
 902                                                alts,
 903                                                subs->cur_audiofmt,
 904                                                subs->cur_rate);
 905                 if (ret < 0)
 906                         goto unlock;
 907
 908                 ret = configure_endpoint(subs);
 909                 if (ret < 0)
 910                         goto unlock;
 911                 subs->need_setup_ep = false;
 912         }
 913
 914         /* some unit conversions in runtime */
 915         subs->data_endpoint->maxframesize =
 916                 bytes_to_frames(runtime, subs->data_endpoint->maxpacksize);
 917         subs->data_endpoint->curframesize =
 918                 bytes_to_frames(runtime, subs->data_endpoint->curpacksize);
 919
 920         /* reset the pointer */
 921         subs->hwptr_done = 0;
 922         subs->transfer_done = 0;
 923         subs->last_delay = 0;
 924         subs->last_frame_number = 0;
 925         runtime->delay = 0;
 926
 927         /* for playback, submit the URBs now; otherwise, the first hwptr_done
 928          * updates for all URBs would happen at the same time when starting */
 929         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
 930                 ret = start_endpoints(subs);
 931
 932  unlock:
 933         snd_usb_unlock_shutdown(subs->stream->chip);
 934         return ret;
 935 }
 936
 937 static const struct snd_pcm_hardware snd_usb_hardware =
 938 {
 939         .info =                 SNDRV_PCM_INFO_MMAP |
 940                                 SNDRV_PCM_INFO_MMAP_VALID |
 941                                 SNDRV_PCM_INFO_BATCH |
 942                                 SNDRV_PCM_INFO_INTERLEAVED |
 943                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
 944                                 SNDRV_PCM_INFO_PAUSE,
 945         .buffer_bytes_max =     1024 * 1024,
 946         .period_bytes_min =     64,
 947         .period_bytes_max =     512 * 1024,
 948         .periods_min =          2,
 949         .periods_max =          1024,
 950 };
 951
 952 static int hw_check_valid_format(struct snd_usb_substream *subs,
 953                                  struct snd_pcm_hw_params *params,
 954                                  struct audioformat *fp)
 955 {
 956         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
 957         struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
 958         struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
 959         struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
 960         struct snd_mask check_fmts;
 961         unsigned int ptime;
 962
 963         /* check the format */
 964         snd_mask_none(&check_fmts);
 965         check_fmts.bits[0] = (u32)fp->formats;
 966         check_fmts.bits[1] = (u32)(fp->formats >> 32);
 967         snd_mask_intersect(&check_fmts, fmts);
 968         if (snd_mask_empty(&check_fmts)) {
 969                 hwc_debug("   > check: no supported format %d\n", fp->format);
 970                 return 0;
 971         }
 972         /* check the channels */
 973         if (fp->channels < ct->min || fp->channels > ct->max) {
 974                 hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
 975                 return 0;
 976         }
 977         /* check the rate is within the range */
 978         if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
 979                 hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
 980                 return 0;
 981         }
 982         if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
 983                 hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
 984                 return 0;
 985         }
 986         /* check whether the period time is >= the data packet interval */
 987         if (subs->speed != USB_SPEED_FULL) {
 988                 ptime = 125 * (1 << fp->datainterval);
 989                 if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
 990                         hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
 991                         return 0;
 992                 }
 993         }
 994         return 1;
 995 }
 996
 997 static int hw_rule_rate(struct snd_pcm_hw_params *params,
 998                         struct snd_pcm_hw_rule *rule)
 999 {
1000         struct snd_usb_substream *subs = rule->private;
1001         struct audioformat *fp;
1002         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1003         unsigned int rmin, rmax;
1004         int changed;
1005
1006         hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
1007         changed = 0;
1008         rmin = rmax = 0;
1009         list_for_each_entry(fp, &subs->fmt_list, list) {
1010                 if (!hw_check_valid_format(subs, params, fp))
1011                         continue;
1012                 if (changed++) {
1013                         if (rmin > fp->rate_min)
1014                                 rmin = fp->rate_min;
1015                         if (rmax < fp->rate_max)
1016                                 rmax = fp->rate_max;
1017                 } else {
1018                         rmin = fp->rate_min;
1019                         rmax = fp->rate_max;
1020                 }
1021         }
1022
1023         if (!changed) {
1024                 hwc_debug("  --> get empty\n");
1025                 it->empty = 1;
1026                 return -EINVAL;
1027         }
1028
1029         changed = 0;
1030         if (it->min < rmin) {
1031                 it->min = rmin;
1032                 it->openmin = 0;
1033                 changed = 1;
1034         }
1035         if (it->max > rmax) {
1036                 it->max = rmax;
1037                 it->openmax = 0;
1038                 changed = 1;
1039         }
1040         if (snd_interval_checkempty(it)) {
1041                 it->empty = 1;
1042                 return -EINVAL;
1043         }
1044         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1045         return changed;
1046 }
1047
1048
1049 static int hw_rule_channels(struct snd_pcm_hw_params *params,
1050                             struct snd_pcm_hw_rule *rule)
1051 {
1052         struct snd_usb_substream *subs = rule->private;
1053         struct audioformat *fp;
1054         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
1055         unsigned int rmin, rmax;
1056         int changed;
1057
1058         hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
1059         changed = 0;
1060         rmin = rmax = 0;
1061         list_for_each_entry(fp, &subs->fmt_list, list) {
1062                 if (!hw_check_valid_format(subs, params, fp))
1063                         continue;
1064                 if (changed++) {
1065                         if (rmin > fp->channels)
1066                                 rmin = fp->channels;
1067                         if (rmax < fp->channels)
1068                                 rmax = fp->channels;
1069                 } else {
1070                         rmin = fp->channels;
1071                         rmax = fp->channels;
1072                 }
1073         }
1074
1075         if (!changed) {
1076                 hwc_debug("  --> get empty\n");
1077                 it->empty = 1;
1078                 return -EINVAL;
1079         }
1080
1081         changed = 0;
1082         if (it->min < rmin) {
1083                 it->min = rmin;
1084                 it->openmin = 0;
1085                 changed = 1;
1086         }
1087         if (it->max > rmax) {
1088                 it->max = rmax;
1089                 it->openmax = 0;
1090                 changed = 1;
1091         }
1092         if (snd_interval_checkempty(it)) {
1093                 it->empty = 1;
1094                 return -EINVAL;
1095         }
1096         hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
1097         return changed;
1098 }
1099
1100 static int hw_rule_format(struct snd_pcm_hw_params *params,
1101                           struct snd_pcm_hw_rule *rule)
1102 {
1103         struct snd_usb_substream *subs = rule->private;
1104         struct audioformat *fp;
1105         struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
1106         u64 fbits;
1107         u32 oldbits[2];
1108         int changed;
1109
1110         hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
1111         fbits = 0;
1112         list_for_each_entry(fp, &subs->fmt_list, list) {
1113                 if (!hw_check_valid_format(subs, params, fp))
1114                         continue;
1115                 fbits |= fp->formats;
1116         }
1117
1118         oldbits[0] = fmt->bits[0];
1119         oldbits[1] = fmt->bits[1];
1120         fmt->bits[0] &= (u32)fbits;
1121         fmt->bits[1] &= (u32)(fbits >> 32);
1122         if (!fmt->bits[0] && !fmt->bits[1]) {
1123                 hwc_debug("  --> get empty\n");
1124                 return -EINVAL;
1125         }
1126         changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
1127         hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
1128         return changed;
1129 }
1130
1131 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
1132                                struct snd_pcm_hw_rule *rule)
1133 {
1134         struct snd_usb_substream *subs = rule->private;
1135         struct audioformat *fp;
1136         struct snd_interval *it;
1137         unsigned char min_datainterval;
1138         unsigned int pmin;
1139         int changed;
1140
1141         it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
1142         hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
1143         min_datainterval = 0xff;
1144         list_for_each_entry(fp, &subs->fmt_list, list) {
1145                 if (!hw_check_valid_format(subs, params, fp))
1146                         continue;
1147                 min_datainterval = min(min_datainterval, fp->datainterval);
1148         }
1149         if (min_datainterval == 0xff) {
1150                 hwc_debug("  --> get empty\n");
1151                 it->empty = 1;
1152                 return -EINVAL;
1153         }
1154         pmin = 125 * (1 << min_datainterval);
1155         changed = 0;
1156         if (it->min < pmin) {
1157                 it->min = pmin;
1158                 it->openmin = 0;
1159                 changed = 1;
1160         }
1161         if (snd_interval_checkempty(it)) {
1162                 it->empty = 1;
1163                 return -EINVAL;
1164         }
1165         hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
1166         return changed;
1167 }
1168
1169 /*
1170  *  If the device supports unusual bit rates, does the request meet these?
1171  */
1172 static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
1173                                   struct snd_usb_substream *subs)
1174 {
1175         struct audioformat *fp;
1176         int *rate_list;
1177         int count = 0, needs_knot = 0;
1178         int err;
1179
1180         kfree(subs->rate_list.list);
1181         subs->rate_list.list = NULL;
1182
1183         list_for_each_entry(fp, &subs->fmt_list, list) {
1184                 if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
1185                         return 0;
1186                 count += fp->nr_rates;
1187                 if (fp->rates & SNDRV_PCM_RATE_KNOT)
1188                         needs_knot = 1;
1189         }
1190         if (!needs_knot)
1191                 return 0;
1192
1193         subs->rate_list.list = rate_list =
1194                 kmalloc_array(count, sizeof(int), GFP_KERNEL);
1195         if (!subs->rate_list.list)
1196                 return -ENOMEM;
1197         subs->rate_list.count = count;
1198         subs->rate_list.mask = 0;
1199         count = 0;
1200         list_for_each_entry(fp, &subs->fmt_list, list) {
1201                 int i;
1202                 for (i = 0; i < fp->nr_rates; i++)
1203                         rate_list[count++] = fp->rate_table[i];
1204         }
1205         err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1206                                          &subs->rate_list);
1207         if (err < 0)
1208                 return err;
1209
1210         return 0;
1211 }
1212
1213
1214 /*
1215  * set up the runtime hardware information.
1216  */
1217
1218 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1219 {
1220         struct audioformat *fp;
1221         unsigned int pt, ptmin;
1222         int param_period_time_if_needed;
1223         int err;
1224
1225         runtime->hw.formats = subs->formats;
1226
1227         runtime->hw.rate_min = 0x7fffffff;
1228         runtime->hw.rate_max = 0;
1229         runtime->hw.channels_min = 256;
1230         runtime->hw.channels_max = 0;
1231         runtime->hw.rates = 0;
1232         ptmin = UINT_MAX;
1233         /* check min/max rates and channels */
1234         list_for_each_entry(fp, &subs->fmt_list, list) {
1235                 runtime->hw.rates |= fp->rates;
1236                 if (runtime->hw.rate_min > fp->rate_min)
1237                         runtime->hw.rate_min = fp->rate_min;
1238                 if (runtime->hw.rate_max < fp->rate_max)
1239                         runtime->hw.rate_max = fp->rate_max;
1240                 if (runtime->hw.channels_min > fp->channels)
1241                         runtime->hw.channels_min = fp->channels;
1242                 if (runtime->hw.channels_max < fp->channels)
1243                         runtime->hw.channels_max = fp->channels;
1244                 if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1245                         /* FIXME: there might be more than one audio formats... */
1246                         runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1247                                 fp->frame_size;
1248                 }
1249                 pt = 125 * (1 << fp->datainterval);
1250                 ptmin = min(ptmin, pt);
1251         }
1252
1253         param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1254         if (subs->speed == USB_SPEED_FULL)
1255                 /* full speed devices have fixed data packet interval */
1256                 ptmin = 1000;
1257         if (ptmin == 1000)
1258                 /* if period time doesn't go below 1 ms, no rules needed */
1259                 param_period_time_if_needed = -1;
1260
1261         err = snd_pcm_hw_constraint_minmax(runtime,
1262                                            SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1263                                            ptmin, UINT_MAX);
1264         if (err < 0)
1265                 return err;
1266
1267         err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1268                                   hw_rule_rate, subs,
1269                                   SNDRV_PCM_HW_PARAM_FORMAT,
1270                                   SNDRV_PCM_HW_PARAM_CHANNELS,
1271                                   param_period_time_if_needed,
1272                                   -1);
1273         if (err < 0)
1274                 return err;
1275         err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1276                                   hw_rule_channels, subs,
1277                                   SNDRV_PCM_HW_PARAM_FORMAT,
1278                                   SNDRV_PCM_HW_PARAM_RATE,
1279                                   param_period_time_if_needed,
1280                                   -1);
1281         if (err < 0)
1282                 return err;
1283         err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1284                                   hw_rule_format, subs,
1285                                   SNDRV_PCM_HW_PARAM_RATE,
1286                                   SNDRV_PCM_HW_PARAM_CHANNELS,
1287                                   param_period_time_if_needed,
1288                                   -1);
1289         if (err < 0)
1290                 return err;
1291         if (param_period_time_if_needed >= 0) {
1292                 err = snd_pcm_hw_rule_add(runtime, 0,
1293                                           SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1294                                           hw_rule_period_time, subs,
1295                                           SNDRV_PCM_HW_PARAM_FORMAT,
1296                                           SNDRV_PCM_HW_PARAM_CHANNELS,
1297                                           SNDRV_PCM_HW_PARAM_RATE,
1298                                           -1);
1299                 if (err < 0)
1300                         return err;
1301         }
1302         err = snd_usb_pcm_check_knot(runtime, subs);
1303         if (err < 0)
1304                 return err;
1305
1306         return snd_usb_autoresume(subs->stream->chip);
1307 }
1308
1309 static int snd_usb_pcm_open(struct snd_pcm_substream *substream)
1310 {
1311         int direction = substream->stream;
1312         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1313         struct snd_pcm_runtime *runtime = substream->runtime;
1314         struct snd_usb_substream *subs = &as->substream[direction];
1315         int ret;
1316
1317         subs->interface = -1;
1318         subs->altset_idx = 0;
1319         runtime->hw = snd_usb_hardware;
1320         runtime->private_data = subs;
1321         subs->pcm_substream = substream;
1322         /* runtime PM is also done there */
1323
1324         /* initialize DSD/DOP context */
1325         subs->dsd_dop.byte_idx = 0;
1326         subs->dsd_dop.channel = 0;
1327         subs->dsd_dop.marker = 1;
1328
1329         ret = setup_hw_info(runtime, subs);
1330         if (ret == 0) {
1331                 ret = snd_media_stream_init(subs, as->pcm, direction);
1332                 if (ret)
1333                         snd_usb_autosuspend(subs->stream->chip);
1334         }
1335         return ret;
1336 }
1337
1338 static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
1339 {
1340         int direction = substream->stream;
1341         struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1342         struct snd_usb_substream *subs = &as->substream[direction];
1343         int ret;
1344
1345         stop_endpoints(subs, true);
1346         snd_media_stop_pipeline(subs);
1347
1348         if (!as->chip->keep_iface &&
1349             subs->interface >= 0 &&
1350             !snd_usb_lock_shutdown(subs->stream->chip)) {
1351                 usb_set_interface(subs->dev, subs->interface, 0);
1352                 subs->interface = -1;
1353                 ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
1354                 snd_usb_unlock_shutdown(subs->stream->chip);
1355                 if (ret < 0)
1356                         return ret;
1357         }
1358
1359         subs->pcm_substream = NULL;
1360         snd_usb_autosuspend(subs->stream->chip);
1361
1362         return 0;
1363 }
1364
1365 /* Since a URB can handle only a single linear buffer, we must use double
1366  * buffering when the data to be transferred overflows the buffer boundary.
1367  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1368  * for all URBs.
1369  */
1370 static void retire_capture_urb(struct snd_usb_substream *subs,
1371                                struct urb *urb)
1372 {
1373         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1374         unsigned int stride, frames, bytes, oldptr;
1375         int i, period_elapsed = 0;
1376         unsigned long flags;
1377         unsigned char *cp;
1378         int current_frame_number;
1379
1380         /* read frame number here, update pointer in critical section */
1381         current_frame_number = usb_get_current_frame_number(subs->dev);
1382
1383         stride = runtime->frame_bits >> 3;
1384
1385         for (i = 0; i < urb->number_of_packets; i++) {
1386                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1387                 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1388                         dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1389                                 i, urb->iso_frame_desc[i].status);
1390                         // continue;
1391                 }
1392                 bytes = urb->iso_frame_desc[i].actual_length;
1393                 frames = bytes / stride;
1394                 if (!subs->txfr_quirk)
1395                         bytes = frames * stride;
1396                 if (bytes % (runtime->sample_bits >> 3) != 0) {
1397                         int oldbytes = bytes;
1398                         bytes = frames * stride;
1399                         dev_warn_ratelimited(&subs->dev->dev,
1400                                  "Corrected urb data len. %d->%d\n",
1401                                                         oldbytes, bytes);
1402                 }
1403                 /* update the current pointer */
1404                 spin_lock_irqsave(&subs->lock, flags);
1405                 oldptr = subs->hwptr_done;
1406                 subs->hwptr_done += bytes;
1407                 if (subs->hwptr_done >= runtime->buffer_size * stride)
1408                         subs->hwptr_done -= runtime->buffer_size * stride;
1409                 frames = (bytes + (oldptr % stride)) / stride;
1410                 subs->transfer_done += frames;
1411                 if (subs->transfer_done >= runtime->period_size) {
1412                         subs->transfer_done -= runtime->period_size;
1413                         period_elapsed = 1;
1414                 }
1415                 /* capture delay is by construction limited to one URB,
1416                  * reset delays here
1417                  */
1418                 runtime->delay = subs->last_delay = 0;
1419
1420                 /* realign last_frame_number */
1421                 subs->last_frame_number = current_frame_number;
1422                 subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1423
1424                 spin_unlock_irqrestore(&subs->lock, flags);
1425                 /* copy a data chunk */
1426                 if (oldptr + bytes > runtime->buffer_size * stride) {
1427                         unsigned int bytes1 =
1428                                         runtime->buffer_size * stride - oldptr;
1429                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
1430                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1431                 } else {
1432                         memcpy(runtime->dma_area + oldptr, cp, bytes);
1433                 }
1434         }
1435
1436         if (period_elapsed)
1437                 snd_pcm_period_elapsed(subs->pcm_substream);
1438 }
1439
1440 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1441                                              struct urb *urb, unsigned int bytes)
1442 {
1443         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1444         unsigned int stride = runtime->frame_bits >> 3;
1445         unsigned int dst_idx = 0;
1446         unsigned int src_idx = subs->hwptr_done;
1447         unsigned int wrap = runtime->buffer_size * stride;
1448         u8 *dst = urb->transfer_buffer;
1449         u8 *src = runtime->dma_area;
1450         u8 marker[] = { 0x05, 0xfa };
1451
1452         /*
1453          * The DSP DOP format defines a way to transport DSD samples over
1454          * normal PCM data endpoints. It requires stuffing of marker bytes
1455          * (0x05 and 0xfa, alternating per sample frame), and then expects
1456          * 2 additional bytes of actual payload. The whole frame is stored
1457          * LSB.
1458          *
1459          * Hence, for a stereo transport, the buffer layout looks like this,
1460          * where L refers to left channel samples and R to right.
1461          *
1462          *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1463          *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1464          *   .....
1465          *
1466          */
1467
1468         while (bytes--) {
1469                 if (++subs->dsd_dop.byte_idx == 3) {
1470                         /* frame boundary? */
1471                         dst[dst_idx++] = marker[subs->dsd_dop.marker];
1472                         src_idx += 2;
1473                         subs->dsd_dop.byte_idx = 0;
1474
1475                         if (++subs->dsd_dop.channel % runtime->channels == 0) {
1476                                 /* alternate the marker */
1477                                 subs->dsd_dop.marker++;
1478                                 subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1479                                 subs->dsd_dop.channel = 0;
1480                         }
1481                 } else {
1482                         /* stuff the DSD payload */
1483                         int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1484
1485                         if (subs->cur_audiofmt->dsd_bitrev)
1486                                 dst[dst_idx++] = bitrev8(src[idx]);
1487                         else
1488                                 dst[dst_idx++] = src[idx];
1489
1490                         subs->hwptr_done++;
1491                 }
1492         }
1493         if (subs->hwptr_done >= runtime->buffer_size * stride)
1494                 subs->hwptr_done -= runtime->buffer_size * stride;
1495 }
1496
1497 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1498                         int offset, int stride, unsigned int bytes)
1499 {
1500         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1501
1502         if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
1503                 /* err, the transferred area goes over buffer boundary. */
1504                 unsigned int bytes1 =
1505                         runtime->buffer_size * stride - subs->hwptr_done;
1506                 memcpy(urb->transfer_buffer + offset,
1507                        runtime->dma_area + subs->hwptr_done, bytes1);
1508                 memcpy(urb->transfer_buffer + offset + bytes1,
1509                        runtime->dma_area, bytes - bytes1);
1510         } else {
1511                 memcpy(urb->transfer_buffer + offset,
1512                        runtime->dma_area + subs->hwptr_done, bytes);
1513         }
1514         subs->hwptr_done += bytes;
1515         if (subs->hwptr_done >= runtime->buffer_size * stride)
1516                 subs->hwptr_done -= runtime->buffer_size * stride;
1517 }
1518
1519 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1520                                       struct urb *urb, int stride,
1521                                       unsigned int bytes)
1522 {
1523         __le32 packet_length;
1524         int i;
1525
1526         /* Put __le32 length descriptor at start of each packet. */
1527         for (i = 0; i < urb->number_of_packets; i++) {
1528                 unsigned int length = urb->iso_frame_desc[i].length;
1529                 unsigned int offset = urb->iso_frame_desc[i].offset;
1530
1531                 packet_length = cpu_to_le32(length);
1532                 offset += i * sizeof(packet_length);
1533                 urb->iso_frame_desc[i].offset = offset;
1534                 urb->iso_frame_desc[i].length += sizeof(packet_length);
1535                 memcpy(urb->transfer_buffer + offset,
1536                        &packet_length, sizeof(packet_length));
1537                 copy_to_urb(subs, urb, offset + sizeof(packet_length),
1538                             stride, length);
1539         }
1540         /* Adjust transfer size accordingly. */
1541         bytes += urb->number_of_packets * sizeof(packet_length);
1542         return bytes;
1543 }
1544
1545 static void prepare_playback_urb(struct snd_usb_substream *subs,
1546                                  struct urb *urb)
1547 {
1548         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1549         struct snd_usb_endpoint *ep = subs->data_endpoint;
1550         struct snd_urb_ctx *ctx = urb->context;
1551         unsigned int counts, frames, bytes;
1552         int i, stride, period_elapsed = 0;
1553         unsigned long flags;
1554
1555         stride = runtime->frame_bits >> 3;
1556
1557         frames = 0;
1558         urb->number_of_packets = 0;
1559         spin_lock_irqsave(&subs->lock, flags);
1560         subs->frame_limit += ep->max_urb_frames;
1561         for (i = 0; i < ctx->packets; i++) {
1562                 if (ctx->packet_size[i])
1563                         counts = ctx->packet_size[i];
1564                 else
1565                         counts = snd_usb_endpoint_next_packet_size(ep);
1566
1567                 /* set up descriptor */
1568                 urb->iso_frame_desc[i].offset = frames * ep->stride;
1569                 urb->iso_frame_desc[i].length = counts * ep->stride;
1570                 frames += counts;
1571                 urb->number_of_packets++;
1572                 subs->transfer_done += counts;
1573                 if (subs->transfer_done >= runtime->period_size) {
1574                         subs->transfer_done -= runtime->period_size;
1575                         subs->frame_limit = 0;
1576                         period_elapsed = 1;
1577                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1578                                 if (subs->transfer_done > 0) {
1579                                         /* FIXME: fill-max mode is not
1580                                          * supported yet */
1581                                         frames -= subs->transfer_done;
1582                                         counts -= subs->transfer_done;
1583                                         urb->iso_frame_desc[i].length =
1584                                                 counts * ep->stride;
1585                                         subs->transfer_done = 0;
1586                                 }
1587                                 i++;
1588                                 if (i < ctx->packets) {
1589                                         /* add a transfer delimiter */
1590                                         urb->iso_frame_desc[i].offset =
1591                                                 frames * ep->stride;
1592                                         urb->iso_frame_desc[i].length = 0;
1593                                         urb->number_of_packets++;
1594                                 }
1595                                 break;
1596                         }
1597                 }
1598                 /* finish at the period boundary or after enough frames */
1599                 if ((period_elapsed ||
1600                                 subs->transfer_done >= subs->frame_limit) &&
1601                     !snd_usb_endpoint_implicit_feedback_sink(ep))
1602                         break;
1603         }
1604         bytes = frames * ep->stride;
1605
1606         if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1607                      subs->cur_audiofmt->dsd_dop)) {
1608                 fill_playback_urb_dsd_dop(subs, urb, bytes);
1609         } else if (unlikely(subs->pcm_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1610                            subs->cur_audiofmt->dsd_bitrev)) {
1611                 /* bit-reverse the bytes */
1612                 u8 *buf = urb->transfer_buffer;
1613                 for (i = 0; i < bytes; i++) {
1614                         int idx = (subs->hwptr_done + i)
1615                                 % (runtime->buffer_size * stride);
1616                         buf[i] = bitrev8(runtime->dma_area[idx]);
1617                 }
1618
1619                 subs->hwptr_done += bytes;
1620                 if (subs->hwptr_done >= runtime->buffer_size * stride)
1621                         subs->hwptr_done -= runtime->buffer_size * stride;
1622         } else {
1623                 /* usual PCM */
1624                 if (!subs->tx_length_quirk)
1625                         copy_to_urb(subs, urb, 0, stride, bytes);
1626                 else
1627                         bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1628                         /* bytes is now amount of outgoing data */
1629         }
1630
1631         /* update delay with exact number of samples queued */
1632         runtime->delay = subs->last_delay;
1633         runtime->delay += frames;
1634         subs->last_delay = runtime->delay;
1635
1636         /* realign last_frame_number */
1637         subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1638         subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
1639
1640         if (subs->trigger_tstamp_pending_update) {
1641                 /* this is the first actual URB submitted,
1642                  * update trigger timestamp to reflect actual start time
1643                  */
1644                 snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1645                 subs->trigger_tstamp_pending_update = false;
1646         }
1647
1648         spin_unlock_irqrestore(&subs->lock, flags);
1649         urb->transfer_buffer_length = bytes;
1650         if (period_elapsed)
1651                 snd_pcm_period_elapsed(subs->pcm_substream);
1652 }
1653
1654 /*
1655  * process after playback data complete
1656  * - decrease the delay count again
1657  */
1658 static void retire_playback_urb(struct snd_usb_substream *subs,
1659                                struct urb *urb)
1660 {
1661         unsigned long flags;
1662         struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1663         struct snd_usb_endpoint *ep = subs->data_endpoint;
1664         int processed = urb->transfer_buffer_length / ep->stride;
1665         int est_delay;
1666
1667         /* ignore the delay accounting when procssed=0 is given, i.e.
1668          * silent payloads are procssed before handling the actual data
1669          */
1670         if (!processed)
1671                 return;
1672
1673         spin_lock_irqsave(&subs->lock, flags);
1674         if (!subs->last_delay)
1675                 goto out; /* short path */
1676
1677         est_delay = snd_usb_pcm_delay(subs, runtime->rate);
1678         /* update delay with exact number of samples played */
1679         if (processed > subs->last_delay)
1680                 subs->last_delay = 0;
1681         else
1682                 subs->last_delay -= processed;
1683         runtime->delay = subs->last_delay;
1684
1685         /*
1686          * Report when delay estimate is off by more than 2ms.
1687          * The error should be lower than 2ms since the estimate relies
1688          * on two reads of a counter updated every ms.
1689          */
1690         if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
1691                 dev_dbg_ratelimited(&subs->dev->dev,
1692                         "delay: estimated %d, actual %d\n",
1693                         est_delay, subs->last_delay);
1694
1695         if (!subs->running) {
1696                 /* update last_frame_number for delay counting here since
1697                  * prepare_playback_urb won't be called during pause
1698                  */
1699                 subs->last_frame_number =
1700                         usb_get_current_frame_number(subs->dev) & 0xff;
1701         }
1702
1703  out:
1704         spin_unlock_irqrestore(&subs->lock, flags);
1705 }
1706
1707 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1708                                               int cmd)
1709 {
1710         struct snd_usb_substream *subs = substream->runtime->private_data;
1711
1712         switch (cmd) {
1713         case SNDRV_PCM_TRIGGER_START:
1714                 subs->trigger_tstamp_pending_update = true;
1715                 /* fall through */
1716         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1717                 subs->data_endpoint->prepare_data_urb = prepare_playback_urb;
1718                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1719                 subs->running = 1;
1720                 return 0;
1721         case SNDRV_PCM_TRIGGER_STOP:
1722                 stop_endpoints(subs, false);
1723                 subs->running = 0;
1724                 return 0;
1725         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1726                 subs->data_endpoint->prepare_data_urb = NULL;
1727                 /* keep retire_data_urb for delay calculation */
1728                 subs->data_endpoint->retire_data_urb = retire_playback_urb;
1729                 subs->running = 0;
1730                 return 0;
1731         }
1732
1733         return -EINVAL;
1734 }
1735
1736 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1737                                              int cmd)
1738 {
1739         int err;
1740         struct snd_usb_substream *subs = substream->runtime->private_data;
1741
1742         switch (cmd) {
1743         case SNDRV_PCM_TRIGGER_START:
1744                 err = start_endpoints(subs);
1745                 if (err < 0)
1746                         return err;
1747
1748                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1749                 subs->running = 1;
1750                 return 0;
1751         case SNDRV_PCM_TRIGGER_STOP:
1752                 stop_endpoints(subs, false);
1753                 subs->running = 0;
1754                 return 0;
1755         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1756                 subs->data_endpoint->retire_data_urb = NULL;
1757                 subs->running = 0;
1758                 return 0;
1759         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1760                 subs->data_endpoint->retire_data_urb = retire_capture_urb;
1761                 subs->running = 1;
1762                 return 0;
1763         }
1764
1765         return -EINVAL;
1766 }
1767
1768 static const struct snd_pcm_ops snd_usb_playback_ops = {
1769         .open =         snd_usb_pcm_open,
1770         .close =        snd_usb_pcm_close,
1771         .ioctl =        snd_pcm_lib_ioctl,
1772         .hw_params =    snd_usb_hw_params,
1773         .hw_free =      snd_usb_hw_free,
1774         .prepare =      snd_usb_pcm_prepare,
1775         .trigger =      snd_usb_substream_playback_trigger,
1776         .pointer =      snd_usb_pcm_pointer,
1777 };
1778
1779 static const struct snd_pcm_ops snd_usb_capture_ops = {
1780         .open =         snd_usb_pcm_open,
1781         .close =        snd_usb_pcm_close,
1782         .ioctl =        snd_pcm_lib_ioctl,
1783         .hw_params =    snd_usb_hw_params,
1784         .hw_free =      snd_usb_hw_free,
1785         .prepare =      snd_usb_pcm_prepare,
1786         .trigger =      snd_usb_substream_capture_trigger,
1787         .pointer =      snd_usb_pcm_pointer,
1788 };
1789
1790 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1791 {
1792         const struct snd_pcm_ops *ops;
1793
1794         ops = stream == SNDRV_PCM_STREAM_PLAYBACK ?
1795                         &snd_usb_playback_ops : &snd_usb_capture_ops;
1796         snd_pcm_set_ops(pcm, stream, ops);
1797 }
1798
1799 void snd_usb_preallocate_buffer(struct snd_usb_substream *subs)
1800 {
1801         struct snd_pcm *pcm = subs->stream->pcm;
1802         struct snd_pcm_substream *s = pcm->streams[subs->direction].substream;
1803         struct device *dev = subs->dev->bus->controller;
1804
1805         if (snd_usb_use_vmalloc)
1806                 snd_pcm_lib_preallocate_pages(s, SNDRV_DMA_TYPE_VMALLOC,
1807                                               NULL, 0, 0);
1808         else
1809                 snd_pcm_lib_preallocate_pages(s, SNDRV_DMA_TYPE_DEV_SG,
1810                                               dev, 64*1024, 512*1024);
1811 }