sound/usb/stream.c

   1 /*
   2  *   This program is free software; you can redistribute it and/or modify
   3  *   it under the terms of the GNU General Public License as published by
   4  *   the Free Software Foundation; either version 2 of the License, or
   5  *   (at your option) any later version.
   6  *
   7  *   This program is distributed in the hope that it will be useful,
   8  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  *   GNU General Public License for more details.
  11  *
  12  *   You should have received a copy of the GNU General Public License
  13  *   along with this program; if not, write to the Free Software
  14  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  15  */
  16
  17
  18 #include <linux/init.h>
  19 #include <linux/slab.h>
  20 #include <linux/usb.h>
  21 #include <linux/usb/audio.h>
  22 #include <linux/usb/audio-v2.h>
  23
  24 #include <sound/core.h>
  25 #include <sound/pcm.h>
  26 #include <sound/control.h>
  27 #include <sound/tlv.h>
  28
  29 #include "usbaudio.h"
  30 #include "card.h"
  31 #include "proc.h"
  32 #include "quirks.h"
  33 #include "endpoint.h"
  34 #include "pcm.h"
  35 #include "helper.h"
  36 #include "format.h"
  37 #include "clock.h"
  38 #include "stream.h"
  39
  40 /*
  41  * free a substream
  42  */
  43 static void free_substream(struct snd_usb_substream *subs)
  44 {
  45         struct audioformat *fp, *n;
  46
  47         if (!subs->num_formats)
  48                 return; /* not initialized */
  49         list_for_each_entry_safe(fp, n, &subs->fmt_list, list) {
  50                 kfree(fp->rate_table);
  51                 kfree(fp->chmap);
  52                 kfree(fp);
  53         }
  54         kfree(subs->rate_list.list);
  55 }
  56
  57
  58 /*
  59  * free a usb stream instance
  60  */
  61 static void snd_usb_audio_stream_free(struct snd_usb_stream *stream)
  62 {
  63         free_substream(&stream->substream[0]);
  64         free_substream(&stream->substream[1]);
  65         list_del(&stream->list);
  66         kfree(stream);
  67 }
  68
  69 static void snd_usb_audio_pcm_free(struct snd_pcm *pcm)
  70 {
  71         struct snd_usb_stream *stream = pcm->private_data;
  72         if (stream) {
  73                 stream->pcm = NULL;
  74                 snd_usb_audio_stream_free(stream);
  75         }
  76 }
  77
  78 /*
  79  * initialize the substream instance.
  80  */
  81
  82 static void snd_usb_init_substream(struct snd_usb_stream *as,
  83                                    int stream,
  84                                    struct audioformat *fp)
  85 {
  86         struct snd_usb_substream *subs = &as->substream[stream];
  87
  88         INIT_LIST_HEAD(&subs->fmt_list);
  89         spin_lock_init(&subs->lock);
  90
  91         subs->stream = as;
  92         subs->direction = stream;
  93         subs->dev = as->chip->dev;
  94         subs->txfr_quirk = as->chip->txfr_quirk;
  95         subs->tx_length_quirk = as->chip->tx_length_quirk;
  96         subs->speed = snd_usb_get_speed(subs->dev);
  97         subs->pkt_offset_adj = 0;
  98
  99         snd_usb_set_pcm_ops(as->pcm, stream);
 100
 101         list_add_tail(&fp->list, &subs->fmt_list);
 102         subs->formats |= fp->formats;
 103         subs->num_formats++;
 104         subs->fmt_type = fp->fmt_type;
 105         subs->ep_num = fp->endpoint;
 106         if (fp->channels > subs->channels_max)
 107                 subs->channels_max = fp->channels;
 108 }
 109
 110 /* kctl callbacks for usb-audio channel maps */
 111 static int usb_chmap_ctl_info(struct snd_kcontrol *kcontrol,
 112                               struct snd_ctl_elem_info *uinfo)
 113 {
 114         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 115         struct snd_usb_substream *subs = info->private_data;
 116
 117         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 118         uinfo->count = subs->channels_max;
 119         uinfo->value.integer.min = 0;
 120         uinfo->value.integer.max = SNDRV_CHMAP_LAST;
 121         return 0;
 122 }
 123
 124 /* check whether a duplicated entry exists in the audiofmt list */
 125 static bool have_dup_chmap(struct snd_usb_substream *subs,
 126                            struct audioformat *fp)
 127 {
 128         struct audioformat *prev = fp;
 129
 130         list_for_each_entry_continue_reverse(prev, &subs->fmt_list, list) {
 131                 if (prev->chmap &&
 132                     !memcmp(prev->chmap, fp->chmap, sizeof(*fp->chmap)))
 133                         return true;
 134         }
 135         return false;
 136 }
 137
 138 static int usb_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
 139                              unsigned int size, unsigned int __user *tlv)
 140 {
 141         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 142         struct snd_usb_substream *subs = info->private_data;
 143         struct audioformat *fp;
 144         unsigned int __user *dst;
 145         int count = 0;
 146
 147         if (size < 8)
 148                 return -ENOMEM;
 149         if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
 150                 return -EFAULT;
 151         size -= 8;
 152         dst = tlv + 2;
 153         list_for_each_entry(fp, &subs->fmt_list, list) {
 154                 int i, ch_bytes;
 155
 156                 if (!fp->chmap)
 157                         continue;
 158                 if (have_dup_chmap(subs, fp))
 159                         continue;
 160                 /* copy the entry */
 161                 ch_bytes = fp->chmap->channels * 4;
 162                 if (size < 8 + ch_bytes)
 163                         return -ENOMEM;
 164                 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
 165                     put_user(ch_bytes, dst + 1))
 166                         return -EFAULT;
 167                 dst += 2;
 168                 for (i = 0; i < fp->chmap->channels; i++, dst++) {
 169                         if (put_user(fp->chmap->map[i], dst))
 170                                 return -EFAULT;
 171                 }
 172
 173                 count += 8 + ch_bytes;
 174                 size -= 8 + ch_bytes;
 175         }
 176         if (put_user(count, tlv + 1))
 177                 return -EFAULT;
 178         return 0;
 179 }
 180
 181 static int usb_chmap_ctl_get(struct snd_kcontrol *kcontrol,
 182                              struct snd_ctl_elem_value *ucontrol)
 183 {
 184         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 185         struct snd_usb_substream *subs = info->private_data;
 186         struct snd_pcm_chmap_elem *chmap = NULL;
 187         int i;
 188
 189         memset(ucontrol->value.integer.value, 0,
 190                sizeof(ucontrol->value.integer.value));
 191         if (subs->cur_audiofmt)
 192                 chmap = subs->cur_audiofmt->chmap;
 193         if (chmap) {
 194                 for (i = 0; i < chmap->channels; i++)
 195                         ucontrol->value.integer.value[i] = chmap->map[i];
 196         }
 197         return 0;
 198 }
 199
 200 /* create a chmap kctl assigned to the given USB substream */
 201 static int add_chmap(struct snd_pcm *pcm, int stream,
 202                      struct snd_usb_substream *subs)
 203 {
 204         struct audioformat *fp;
 205         struct snd_pcm_chmap *chmap;
 206         struct snd_kcontrol *kctl;
 207         int err;
 208
 209         list_for_each_entry(fp, &subs->fmt_list, list)
 210                 if (fp->chmap)
 211                         goto ok;
 212         /* no chmap is found */
 213         return 0;
 214
 215  ok:
 216         err = snd_pcm_add_chmap_ctls(pcm, stream, NULL, 0, 0, &chmap);
 217         if (err < 0)
 218                 return err;
 219
 220         /* override handlers */
 221         chmap->private_data = subs;
 222         kctl = chmap->kctl;
 223         kctl->info = usb_chmap_ctl_info;
 224         kctl->get = usb_chmap_ctl_get;
 225         kctl->tlv.c = usb_chmap_ctl_tlv;
 226
 227         return 0;
 228 }
 229
 230 /* convert from USB ChannelConfig bits to ALSA chmap element */
 231 static struct snd_pcm_chmap_elem *convert_chmap(int channels, unsigned int bits,
 232                                                 int protocol)
 233 {
 234         static unsigned int uac1_maps[] = {
 235                 SNDRV_CHMAP_FL,         /* left front */
 236                 SNDRV_CHMAP_FR,         /* right front */
 237                 SNDRV_CHMAP_FC,         /* center front */
 238                 SNDRV_CHMAP_LFE,        /* LFE */
 239                 SNDRV_CHMAP_SL,         /* left surround */
 240                 SNDRV_CHMAP_SR,         /* right surround */
 241                 SNDRV_CHMAP_FLC,        /* left of center */
 242                 SNDRV_CHMAP_FRC,        /* right of center */
 243                 SNDRV_CHMAP_RC,         /* surround */
 244                 SNDRV_CHMAP_SL,         /* side left */
 245                 SNDRV_CHMAP_SR,         /* side right */
 246                 SNDRV_CHMAP_TC,         /* top */
 247                 0 /* terminator */
 248         };
 249         static unsigned int uac2_maps[] = {
 250                 SNDRV_CHMAP_FL,         /* front left */
 251                 SNDRV_CHMAP_FR,         /* front right */
 252                 SNDRV_CHMAP_FC,         /* front center */
 253                 SNDRV_CHMAP_LFE,        /* LFE */
 254                 SNDRV_CHMAP_RL,         /* back left */
 255                 SNDRV_CHMAP_RR,         /* back right */
 256                 SNDRV_CHMAP_FLC,        /* front left of center */
 257                 SNDRV_CHMAP_FRC,        /* front right of center */
 258                 SNDRV_CHMAP_RC,         /* back center */
 259                 SNDRV_CHMAP_SL,         /* side left */
 260                 SNDRV_CHMAP_SR,         /* side right */
 261                 SNDRV_CHMAP_TC,         /* top center */
 262                 SNDRV_CHMAP_TFL,        /* top front left */
 263                 SNDRV_CHMAP_TFC,        /* top front center */
 264                 SNDRV_CHMAP_TFR,        /* top front right */
 265                 SNDRV_CHMAP_TRL,        /* top back left */
 266                 SNDRV_CHMAP_TRC,        /* top back center */
 267                 SNDRV_CHMAP_TRR,        /* top back right */
 268                 SNDRV_CHMAP_TFLC,       /* top front left of center */
 269                 SNDRV_CHMAP_TFRC,       /* top front right of center */
 270                 SNDRV_CHMAP_LLFE,       /* left LFE */
 271                 SNDRV_CHMAP_RLFE,       /* right LFE */
 272                 SNDRV_CHMAP_TSL,        /* top side left */
 273                 SNDRV_CHMAP_TSR,        /* top side right */
 274                 SNDRV_CHMAP_BC,         /* bottom center */
 275                 SNDRV_CHMAP_RLC,        /* back left of center */
 276                 SNDRV_CHMAP_RRC,        /* back right of center */
 277                 0 /* terminator */
 278         };
 279         struct snd_pcm_chmap_elem *chmap;
 280         const unsigned int *maps;
 281         int c;
 282
 283         if (channels > ARRAY_SIZE(chmap->map))
 284                 return NULL;
 285
 286         chmap = kzalloc(sizeof(*chmap), GFP_KERNEL);
 287         if (!chmap)
 288                 return NULL;
 289
 290         maps = protocol == UAC_VERSION_2 ? uac2_maps : uac1_maps;
 291         chmap->channels = channels;
 292         c = 0;
 293
 294         if (bits) {
 295                 for (; bits && *maps; maps++, bits >>= 1)
 296                         if (bits & 1)
 297                                 chmap->map[c++] = *maps;
 298         } else {
 299                 /* If we're missing wChannelConfig, then guess something
 300                     to make sure the channel map is not skipped entirely */
 301                 if (channels == 1)
 302                         chmap->map[c++] = SNDRV_CHMAP_MONO;
 303                 else
 304                         for (; c < channels && *maps; maps++)
 305                                 chmap->map[c++] = *maps;
 306         }
 307
 308         for (; c < channels; c++)
 309                 chmap->map[c] = SNDRV_CHMAP_UNKNOWN;
 310
 311         return chmap;
 312 }
 313
 314 /*
 315  * add this endpoint to the chip instance.
 316  * if a stream with the same endpoint already exists, append to it.
 317  * if not, create a new pcm stream.
 318  */
 319 int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
 320                              int stream,
 321                              struct audioformat *fp)
 322 {
 323         struct snd_usb_stream *as;
 324         struct snd_usb_substream *subs;
 325         struct snd_pcm *pcm;
 326         int err;
 327
 328         list_for_each_entry(as, &chip->pcm_list, list) {
 329                 if (as->fmt_type != fp->fmt_type)
 330                         continue;
 331                 subs = &as->substream[stream];
 332                 if (subs->ep_num == fp->endpoint) {
 333                         list_add_tail(&fp->list, &subs->fmt_list);
 334                         subs->num_formats++;
 335                         subs->formats |= fp->formats;
 336                         return 0;
 337                 }
 338         }
 339         /* look for an empty stream */
 340         list_for_each_entry(as, &chip->pcm_list, list) {
 341                 if (as->fmt_type != fp->fmt_type)
 342                         continue;
 343                 subs = &as->substream[stream];
 344                 if (subs->ep_num)
 345                         continue;
 346                 err = snd_pcm_new_stream(as->pcm, stream, 1);
 347                 if (err < 0)
 348                         return err;
 349                 snd_usb_init_substream(as, stream, fp);
 350                 return add_chmap(as->pcm, stream, subs);
 351         }
 352
 353         /* create a new pcm */
 354         as = kzalloc(sizeof(*as), GFP_KERNEL);
 355         if (!as)
 356                 return -ENOMEM;
 357         as->pcm_index = chip->pcm_devs;
 358         as->chip = chip;
 359         as->fmt_type = fp->fmt_type;
 360         err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
 361                           stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
 362                           stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
 363                           &pcm);
 364         if (err < 0) {
 365                 kfree(as);
 366                 return err;
 367         }
 368         as->pcm = pcm;
 369         pcm->private_data = as;
 370         pcm->private_free = snd_usb_audio_pcm_free;
 371         pcm->info_flags = 0;
 372         if (chip->pcm_devs > 0)
 373                 sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
 374         else
 375                 strcpy(pcm->name, "USB Audio");
 376
 377         snd_usb_init_substream(as, stream, fp);
 378
 379         /*
 380          * Keep using head insertion for M-Audio Audiophile USB (tm) which has a
 381          * fix to swap capture stream order in conf/cards/USB-audio.conf
 382          */
 383         if (chip->usb_id == USB_ID(0x0763, 0x2003))
 384                 list_add(&as->list, &chip->pcm_list);
 385         else
 386                 list_add_tail(&as->list, &chip->pcm_list);
 387
 388         chip->pcm_devs++;
 389
 390         snd_usb_proc_pcm_format_add(as);
 391
 392         return add_chmap(pcm, stream, &as->substream[stream]);
 393 }
 394
 395 static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
 396                                          struct usb_host_interface *alts,
 397                                          int protocol, int iface_no)
 398 {
 399         /* parsed with a v1 header here. that's ok as we only look at the
 400          * header first which is the same for both versions */
 401         struct uac_iso_endpoint_descriptor *csep;
 402         struct usb_interface_descriptor *altsd = get_iface_desc(alts);
 403         int attributes = 0;
 404
 405         csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
 406
 407         /* Creamware Noah has this descriptor after the 2nd endpoint */
 408         if (!csep && altsd->bNumEndpoints >= 2)
 409                 csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
 410
 411         /*
 412          * If we can't locate the USB_DT_CS_ENDPOINT descriptor in the extra
 413          * bytes after the first endpoint, go search the entire interface.
 414          * Some devices have it directly *before* the standard endpoint.
 415          */
 416         if (!csep)
 417                 csep = snd_usb_find_desc(alts->extra, alts->extralen, NULL, USB_DT_CS_ENDPOINT);
 418
 419         if (!csep || csep->bLength < 7 ||
 420             csep->bDescriptorSubtype != UAC_EP_GENERAL) {
 421                 usb_audio_warn(chip,
 422                                "%u:%d : no or invalid class specific endpoint descriptor\n",
 423                                iface_no, altsd->bAlternateSetting);
 424                 return 0;
 425         }
 426
 427         if (protocol == UAC_VERSION_1) {
 428                 attributes = csep->bmAttributes;
 429         } else {
 430                 struct uac2_iso_endpoint_descriptor *csep2 =
 431                         (struct uac2_iso_endpoint_descriptor *) csep;
 432
 433                 attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
 434
 435                 /* emulate the endpoint attributes of a v1 device */
 436                 if (csep2->bmControls & UAC2_CONTROL_PITCH)
 437                         attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
 438         }
 439
 440         return attributes;
 441 }
 442
 443 /* find an input terminal descriptor (either UAC1 or UAC2) with the given
 444  * terminal id
 445  */
 446 static void *
 447 snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
 448                                                int terminal_id)
 449 {
 450         struct uac2_input_terminal_descriptor *term = NULL;
 451
 452         while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
 453                                                ctrl_iface->extralen,
 454                                                term, UAC_INPUT_TERMINAL))) {
 455                 if (term->bTerminalID == terminal_id)
 456                         return term;
 457         }
 458
 459         return NULL;
 460 }
 461
 462 static struct uac2_output_terminal_descriptor *
 463         snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
 464                                                 int terminal_id)
 465 {
 466         struct uac2_output_terminal_descriptor *term = NULL;
 467
 468         while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
 469                                                ctrl_iface->extralen,
 470                                                term, UAC_OUTPUT_TERMINAL))) {
 471                 if (term->bTerminalID == terminal_id)
 472                         return term;
 473         }
 474
 475         return NULL;
 476 }
 477
 478 int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
 479 {
 480         struct usb_device *dev;
 481         struct usb_interface *iface;
 482         struct usb_host_interface *alts;
 483         struct usb_interface_descriptor *altsd;
 484         int i, altno, err, stream;
 485         unsigned int format = 0, num_channels = 0;
 486         struct audioformat *fp = NULL;
 487         int num, protocol, clock = 0;
 488         struct uac_format_type_i_continuous_descriptor *fmt;
 489         unsigned int chconfig;
 490
 491         dev = chip->dev;
 492
 493         /* parse the interface's altsettings */
 494         iface = usb_ifnum_to_if(dev, iface_no);
 495
 496         num = iface->num_altsetting;
 497
 498         /*
 499          * Dallas DS4201 workaround: It presents 5 altsettings, but the last
 500          * one misses syncpipe, and does not produce any sound.
 501          */
 502         if (chip->usb_id == USB_ID(0x04fa, 0x4201))
 503                 num = 4;
 504
 505         for (i = 0; i < num; i++) {
 506                 alts = &iface->altsetting[i];
 507                 altsd = get_iface_desc(alts);
 508                 protocol = altsd->bInterfaceProtocol;
 509                 /* skip invalid one */
 510                 if (((altsd->bInterfaceClass != USB_CLASS_AUDIO ||
 511                       (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
 512                        altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC)) &&
 513                      altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 514                     altsd->bNumEndpoints < 1 ||
 515                     le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
 516                         continue;
 517                 /* must be isochronous */
 518                 if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
 519                     USB_ENDPOINT_XFER_ISOC)
 520                         continue;
 521                 /* check direction */
 522                 stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
 523                         SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
 524                 altno = altsd->bAlternateSetting;
 525
 526                 if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
 527                         continue;
 528
 529                 /*
 530                  * Roland audio streaming interfaces are marked with protocols
 531                  * 0/1/2, but are UAC 1 compatible.
 532                  */
 533                 if (USB_ID_VENDOR(chip->usb_id) == 0x0582 &&
 534                     altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 535                     protocol <= 2)
 536                         protocol = UAC_VERSION_1;
 537
 538                 chconfig = 0;
 539                 /* get audio formats */
 540                 switch (protocol) {
 541                 default:
 542                         dev_dbg(&dev->dev, "%u:%d: unknown interface protocol %#02x, assuming v1\n",
 543                                 iface_no, altno, protocol);
 544                         protocol = UAC_VERSION_1;
 545                         /* fall through */
 546
 547                 case UAC_VERSION_1: {
 548                         struct uac1_as_header_descriptor *as =
 549                                 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
 550                         struct uac_input_terminal_descriptor *iterm;
 551
 552                         if (!as) {
 553                                 dev_err(&dev->dev,
 554                                         "%u:%d : UAC_AS_GENERAL descriptor not found\n",
 555                                         iface_no, altno);
 556                                 continue;
 557                         }
 558
 559                         if (as->bLength < sizeof(*as)) {
 560                                 dev_err(&dev->dev,
 561                                         "%u:%d : invalid UAC_AS_GENERAL desc\n",
 562                                         iface_no, altno);
 563                                 continue;
 564                         }
 565
 566                         format = le16_to_cpu(as->wFormatTag); /* remember the format value */
 567
 568                         iterm = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
 569                                                                        as->bTerminalLink);
 570                         if (iterm) {
 571                                 num_channels = iterm->bNrChannels;
 572                                 chconfig = le16_to_cpu(iterm->wChannelConfig);
 573                         }
 574
 575                         break;
 576                 }
 577
 578                 case UAC_VERSION_2: {
 579                         struct uac2_input_terminal_descriptor *input_term;
 580                         struct uac2_output_terminal_descriptor *output_term;
 581                         struct uac2_as_header_descriptor *as =
 582                                 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
 583
 584                         if (!as) {
 585                                 dev_err(&dev->dev,
 586                                         "%u:%d : UAC_AS_GENERAL descriptor not found\n",
 587                                         iface_no, altno);
 588                                 continue;
 589                         }
 590
 591                         if (as->bLength < sizeof(*as)) {
 592                                 dev_err(&dev->dev,
 593                                         "%u:%d : invalid UAC_AS_GENERAL desc\n",
 594                                         iface_no, altno);
 595                                 continue;
 596                         }
 597
 598                         num_channels = as->bNrChannels;
 599                         format = le32_to_cpu(as->bmFormats);
 600                         chconfig = le32_to_cpu(as->bmChannelConfig);
 601
 602                         /* lookup the terminal associated to this interface
 603                          * to extract the clock */
 604                         input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
 605                                                                             as->bTerminalLink);
 606                         if (input_term) {
 607                                 clock = input_term->bCSourceID;
 608                                 if (!chconfig && (num_channels == input_term->bNrChannels))
 609                                         chconfig = le32_to_cpu(input_term->bmChannelConfig);
 610                                 break;
 611                         }
 612
 613                         output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
 614                                                                               as->bTerminalLink);
 615                         if (output_term) {
 616                                 clock = output_term->bCSourceID;
 617                                 break;
 618                         }
 619
 620                         dev_err(&dev->dev,
 621                                 "%u:%d : bogus bTerminalLink %d\n",
 622                                 iface_no, altno, as->bTerminalLink);
 623                         continue;
 624                 }
 625                 }
 626
 627                 /* get format type */
 628                 fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
 629                 if (!fmt) {
 630                         dev_err(&dev->dev,
 631                                 "%u:%d : no UAC_FORMAT_TYPE desc\n",
 632                                 iface_no, altno);
 633                         continue;
 634                 }
 635                 if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
 636                     ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
 637                         dev_err(&dev->dev,
 638                                 "%u:%d : invalid UAC_FORMAT_TYPE desc\n",
 639                                 iface_no, altno);
 640                         continue;
 641                 }
 642
 643                 /*
 644                  * Blue Microphones workaround: The last altsetting is identical
 645                  * with the previous one, except for a larger packet size, but
 646                  * is actually a mislabeled two-channel setting; ignore it.
 647                  */
 648                 if (fmt->bNrChannels == 1 &&
 649                     fmt->bSubframeSize == 2 &&
 650                     altno == 2 && num == 3 &&
 651                     fp && fp->altsetting == 1 && fp->channels == 1 &&
 652                     fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
 653                     protocol == UAC_VERSION_1 &&
 654                     le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
 655                                                         fp->maxpacksize * 2)
 656                         continue;
 657
 658                 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
 659                 if (! fp) {
 660                         dev_err(&dev->dev, "cannot malloc\n");
 661                         return -ENOMEM;
 662                 }
 663
 664                 fp->iface = iface_no;
 665                 fp->altsetting = altno;
 666                 fp->altset_idx = i;
 667                 fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
 668                 fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
 669                 fp->datainterval = snd_usb_parse_datainterval(chip, alts);
 670                 fp->protocol = protocol;
 671                 fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
 672                 fp->channels = num_channels;
 673                 if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
 674                         fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
 675                                         * (fp->maxpacksize & 0x7ff);
 676                 fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
 677                 fp->clock = clock;
 678
 679                 /* some quirks for attributes here */
 680
 681                 switch (chip->usb_id) {
 682                 case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
 683                         /* Optoplay sets the sample rate attribute although
 684                          * it seems not supporting it in fact.
 685                          */
 686                         fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
 687                         break;
 688                 case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
 689                 case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
 690                         /* doesn't set the sample rate attribute, but supports it */
 691                         fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
 692                         break;
 693                 case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
 694                 case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
 695                 case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
 696                 case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
 697                                                 an older model 77d:223) */
 698                 /*
 699                  * plantronics headset and Griffin iMic have set adaptive-in
 700                  * although it's really not...
 701                  */
 702                         fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
 703                         if (stream == SNDRV_PCM_STREAM_PLAYBACK)
 704                                 fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
 705                         else
 706                                 fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
 707                         break;
 708                 }
 709
 710                 /* ok, let's parse further... */
 711                 if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream) < 0) {
 712                         kfree(fp->rate_table);
 713                         kfree(fp);
 714                         fp = NULL;
 715                         continue;
 716                 }
 717
 718                 /* Create chmap */
 719                 if (fp->channels != num_channels)
 720                         chconfig = 0;
 721                 fp->chmap = convert_chmap(fp->channels, chconfig, protocol);
 722
 723                 dev_dbg(&dev->dev, "%u:%d: add audio endpoint %#x\n", iface_no, altno, fp->endpoint);
 724                 err = snd_usb_add_audio_stream(chip, stream, fp);
 725                 if (err < 0) {
 726                         kfree(fp->rate_table);
 727                         kfree(fp->chmap);
 728                         kfree(fp);
 729                         return err;
 730                 }
 731                 /* try to set the interface... */
 732                 usb_set_interface(chip->dev, iface_no, altno);
 733                 snd_usb_init_pitch(chip, iface_no, alts, fp);
 734                 snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
 735         }
 736         return 0;
 737 }
 738