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         subs->stream_offset_adj = 0;
  99
 100         snd_usb_set_pcm_ops(as->pcm, stream);
 101
 102         list_add_tail(&fp->list, &subs->fmt_list);
 103         subs->formats |= fp->formats;
 104         subs->num_formats++;
 105         subs->fmt_type = fp->fmt_type;
 106         subs->ep_num = fp->endpoint;
 107         if (fp->channels > subs->channels_max)
 108                 subs->channels_max = fp->channels;
 109 }
 110
 111 /* kctl callbacks for usb-audio channel maps */
 112 static int usb_chmap_ctl_info(struct snd_kcontrol *kcontrol,
 113                               struct snd_ctl_elem_info *uinfo)
 114 {
 115         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 116         struct snd_usb_substream *subs = info->private_data;
 117
 118         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 119         uinfo->count = subs->channels_max;
 120         uinfo->value.integer.min = 0;
 121         uinfo->value.integer.max = SNDRV_CHMAP_LAST;
 122         return 0;
 123 }
 124
 125 /* check whether a duplicated entry exists in the audiofmt list */
 126 static bool have_dup_chmap(struct snd_usb_substream *subs,
 127                            struct audioformat *fp)
 128 {
 129         struct list_head *p;
 130
 131         for (p = fp->list.prev; p != &subs->fmt_list; p = p->prev) {
 132                 struct audioformat *prev;
 133                 prev = list_entry(p, struct audioformat, list);
 134                 if (prev->chmap &&
 135                     !memcmp(prev->chmap, fp->chmap, sizeof(*fp->chmap)))
 136                         return true;
 137         }
 138         return false;
 139 }
 140
 141 static int usb_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
 142                              unsigned int size, unsigned int __user *tlv)
 143 {
 144         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 145         struct snd_usb_substream *subs = info->private_data;
 146         struct audioformat *fp;
 147         unsigned int __user *dst;
 148         int count = 0;
 149
 150         if (size < 8)
 151                 return -ENOMEM;
 152         if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
 153                 return -EFAULT;
 154         size -= 8;
 155         dst = tlv + 2;
 156         list_for_each_entry(fp, &subs->fmt_list, list) {
 157                 int i, ch_bytes;
 158
 159                 if (!fp->chmap)
 160                         continue;
 161                 if (have_dup_chmap(subs, fp))
 162                         continue;
 163                 /* copy the entry */
 164                 ch_bytes = fp->chmap->channels * 4;
 165                 if (size < 8 + ch_bytes)
 166                         return -ENOMEM;
 167                 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
 168                     put_user(ch_bytes, dst + 1))
 169                         return -EFAULT;
 170                 dst += 2;
 171                 for (i = 0; i < fp->chmap->channels; i++, dst++) {
 172                         if (put_user(fp->chmap->map[i], dst))
 173                                 return -EFAULT;
 174                 }
 175
 176                 count += 8 + ch_bytes;
 177                 size -= 8 + ch_bytes;
 178         }
 179         if (put_user(count, tlv + 1))
 180                 return -EFAULT;
 181         return 0;
 182 }
 183
 184 static int usb_chmap_ctl_get(struct snd_kcontrol *kcontrol,
 185                              struct snd_ctl_elem_value *ucontrol)
 186 {
 187         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 188         struct snd_usb_substream *subs = info->private_data;
 189         struct snd_pcm_chmap_elem *chmap = NULL;
 190         int i = 0;
 191
 192         if (subs->cur_audiofmt)
 193                 chmap = subs->cur_audiofmt->chmap;
 194         if (chmap) {
 195                 for (i = 0; i < chmap->channels; i++)
 196                         ucontrol->value.integer.value[i] = chmap->map[i];
 197         }
 198         for (; i < subs->channels_max; i++)
 199                 ucontrol->value.integer.value[i] = 0;
 200         return 0;
 201 }
 202
 203 /* create a chmap kctl assigned to the given USB substream */
 204 static int add_chmap(struct snd_pcm *pcm, int stream,
 205                      struct snd_usb_substream *subs)
 206 {
 207         struct audioformat *fp;
 208         struct snd_pcm_chmap *chmap;
 209         struct snd_kcontrol *kctl;
 210         int err;
 211
 212         list_for_each_entry(fp, &subs->fmt_list, list)
 213                 if (fp->chmap)
 214                         goto ok;
 215         /* no chmap is found */
 216         return 0;
 217
 218  ok:
 219         err = snd_pcm_add_chmap_ctls(pcm, stream, NULL, 0, 0, &chmap);
 220         if (err < 0)
 221                 return err;
 222
 223         /* override handlers */
 224         chmap->private_data = subs;
 225         kctl = chmap->kctl;
 226         kctl->info = usb_chmap_ctl_info;
 227         kctl->get = usb_chmap_ctl_get;
 228         kctl->tlv.c = usb_chmap_ctl_tlv;
 229
 230         return 0;
 231 }
 232
 233 /* convert from USB ChannelConfig bits to ALSA chmap element */
 234 static struct snd_pcm_chmap_elem *convert_chmap(int channels, unsigned int bits,
 235                                                 int protocol)
 236 {
 237         static unsigned int uac1_maps[] = {
 238                 SNDRV_CHMAP_FL,         /* left front */
 239                 SNDRV_CHMAP_FR,         /* right front */
 240                 SNDRV_CHMAP_FC,         /* center front */
 241                 SNDRV_CHMAP_LFE,        /* LFE */
 242                 SNDRV_CHMAP_SL,         /* left surround */
 243                 SNDRV_CHMAP_SR,         /* right surround */
 244                 SNDRV_CHMAP_FLC,        /* left of center */
 245                 SNDRV_CHMAP_FRC,        /* right of center */
 246                 SNDRV_CHMAP_RC,         /* surround */
 247                 SNDRV_CHMAP_SL,         /* side left */
 248                 SNDRV_CHMAP_SR,         /* side right */
 249                 SNDRV_CHMAP_TC,         /* top */
 250                 0 /* terminator */
 251         };
 252         static unsigned int uac2_maps[] = {
 253                 SNDRV_CHMAP_FL,         /* front left */
 254                 SNDRV_CHMAP_FR,         /* front right */
 255                 SNDRV_CHMAP_FC,         /* front center */
 256                 SNDRV_CHMAP_LFE,        /* LFE */
 257                 SNDRV_CHMAP_RL,         /* back left */
 258                 SNDRV_CHMAP_RR,         /* back right */
 259                 SNDRV_CHMAP_FLC,        /* front left of center */
 260                 SNDRV_CHMAP_FRC,        /* front right of center */
 261                 SNDRV_CHMAP_RC,         /* back center */
 262                 SNDRV_CHMAP_SL,         /* side left */
 263                 SNDRV_CHMAP_SR,         /* side right */
 264                 SNDRV_CHMAP_TC,         /* top center */
 265                 SNDRV_CHMAP_TFL,        /* top front left */
 266                 SNDRV_CHMAP_TFC,        /* top front center */
 267                 SNDRV_CHMAP_TFR,        /* top front right */
 268                 SNDRV_CHMAP_TRL,        /* top back left */
 269                 SNDRV_CHMAP_TRC,        /* top back center */
 270                 SNDRV_CHMAP_TRR,        /* top back right */
 271                 SNDRV_CHMAP_TFLC,       /* top front left of center */
 272                 SNDRV_CHMAP_TFRC,       /* top front right of center */
 273                 SNDRV_CHMAP_LLFE,       /* left LFE */
 274                 SNDRV_CHMAP_RLFE,       /* right LFE */
 275                 SNDRV_CHMAP_TSL,        /* top side left */
 276                 SNDRV_CHMAP_TSR,        /* top side right */
 277                 SNDRV_CHMAP_BC,         /* bottom center */
 278                 SNDRV_CHMAP_RLC,        /* back left of center */
 279                 SNDRV_CHMAP_RRC,        /* back right of center */
 280                 0 /* terminator */
 281         };
 282         struct snd_pcm_chmap_elem *chmap;
 283         const unsigned int *maps;
 284         int c;
 285
 286         if (channels > ARRAY_SIZE(chmap->map))
 287                 return NULL;
 288
 289         chmap = kzalloc(sizeof(*chmap), GFP_KERNEL);
 290         if (!chmap)
 291                 return NULL;
 292
 293         maps = protocol == UAC_VERSION_2 ? uac2_maps : uac1_maps;
 294         chmap->channels = channels;
 295         c = 0;
 296
 297         if (bits) {
 298                 for (; bits && *maps; maps++, bits >>= 1)
 299                         if (bits & 1)
 300                                 chmap->map[c++] = *maps;
 301         } else {
 302                 /* If we're missing wChannelConfig, then guess something
 303                     to make sure the channel map is not skipped entirely */
 304                 if (channels == 1)
 305                         chmap->map[c++] = SNDRV_CHMAP_MONO;
 306                 else
 307                         for (; c < channels && *maps; maps++)
 308                                 chmap->map[c++] = *maps;
 309         }
 310
 311         for (; c < channels; c++)
 312                 chmap->map[c] = SNDRV_CHMAP_UNKNOWN;
 313
 314         return chmap;
 315 }
 316
 317 /*
 318  * add this endpoint to the chip instance.
 319  * if a stream with the same endpoint already exists, append to it.
 320  * if not, create a new pcm stream. note, fp is added to the substream
 321  * fmt_list and will be freed on the chip instance release. do not free
 322  * fp or do remove it from the substream fmt_list to avoid double-free.
 323  */
 324 int snd_usb_add_audio_stream(struct snd_usb_audio *chip,
 325                              int stream,
 326                              struct audioformat *fp)
 327 {
 328         struct snd_usb_stream *as;
 329         struct snd_usb_substream *subs;
 330         struct snd_pcm *pcm;
 331         int err;
 332
 333         list_for_each_entry(as, &chip->pcm_list, list) {
 334                 if (as->fmt_type != fp->fmt_type)
 335                         continue;
 336                 subs = &as->substream[stream];
 337                 if (subs->ep_num == fp->endpoint) {
 338                         list_add_tail(&fp->list, &subs->fmt_list);
 339                         subs->num_formats++;
 340                         subs->formats |= fp->formats;
 341                         return 0;
 342                 }
 343         }
 344         /* look for an empty stream */
 345         list_for_each_entry(as, &chip->pcm_list, list) {
 346                 if (as->fmt_type != fp->fmt_type)
 347                         continue;
 348                 subs = &as->substream[stream];
 349                 if (subs->ep_num)
 350                         continue;
 351                 err = snd_pcm_new_stream(as->pcm, stream, 1);
 352                 if (err < 0)
 353                         return err;
 354                 snd_usb_init_substream(as, stream, fp);
 355                 return add_chmap(as->pcm, stream, subs);
 356         }
 357
 358         /* create a new pcm */
 359         as = kzalloc(sizeof(*as), GFP_KERNEL);
 360         if (!as)
 361                 return -ENOMEM;
 362         as->pcm_index = chip->pcm_devs;
 363         as->chip = chip;
 364         as->fmt_type = fp->fmt_type;
 365         err = snd_pcm_new(chip->card, "USB Audio", chip->pcm_devs,
 366                           stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0,
 367                           stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1,
 368                           &pcm);
 369         if (err < 0) {
 370                 kfree(as);
 371                 return err;
 372         }
 373         as->pcm = pcm;
 374         pcm->private_data = as;
 375         pcm->private_free = snd_usb_audio_pcm_free;
 376         pcm->info_flags = 0;
 377         if (chip->pcm_devs > 0)
 378                 sprintf(pcm->name, "USB Audio #%d", chip->pcm_devs);
 379         else
 380                 strcpy(pcm->name, "USB Audio");
 381
 382         snd_usb_init_substream(as, stream, fp);
 383
 384         /*
 385          * Keep using head insertion for M-Audio Audiophile USB (tm) which has a
 386          * fix to swap capture stream order in conf/cards/USB-audio.conf
 387          */
 388         if (chip->usb_id == USB_ID(0x0763, 0x2003))
 389                 list_add(&as->list, &chip->pcm_list);
 390         else
 391                 list_add_tail(&as->list, &chip->pcm_list);
 392
 393         chip->pcm_devs++;
 394
 395         snd_usb_proc_pcm_format_add(as);
 396
 397         return add_chmap(pcm, stream, &as->substream[stream]);
 398 }
 399
 400 static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
 401                                          struct usb_host_interface *alts,
 402                                          int protocol, int iface_no)
 403 {
 404         /* parsed with a v1 header here. that's ok as we only look at the
 405          * header first which is the same for both versions */
 406         struct uac_iso_endpoint_descriptor *csep;
 407         struct usb_interface_descriptor *altsd = get_iface_desc(alts);
 408         int attributes = 0;
 409
 410         csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
 411
 412         /* Creamware Noah has this descriptor after the 2nd endpoint */
 413         if (!csep && altsd->bNumEndpoints >= 2)
 414                 csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
 415
 416         /*
 417          * If we can't locate the USB_DT_CS_ENDPOINT descriptor in the extra
 418          * bytes after the first endpoint, go search the entire interface.
 419          * Some devices have it directly *before* the standard endpoint.
 420          */
 421         if (!csep)
 422                 csep = snd_usb_find_desc(alts->extra, alts->extralen, NULL, USB_DT_CS_ENDPOINT);
 423
 424         if (!csep || csep->bLength < 7 ||
 425             csep->bDescriptorSubtype != UAC_EP_GENERAL) {
 426                 usb_audio_warn(chip,
 427                                "%u:%d : no or invalid class specific endpoint descriptor\n",
 428                                iface_no, altsd->bAlternateSetting);
 429                 return 0;
 430         }
 431
 432         if (protocol == UAC_VERSION_1) {
 433                 attributes = csep->bmAttributes;
 434         } else {
 435                 struct uac2_iso_endpoint_descriptor *csep2 =
 436                         (struct uac2_iso_endpoint_descriptor *) csep;
 437
 438                 attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
 439
 440                 /* emulate the endpoint attributes of a v1 device */
 441                 if (csep2->bmControls & UAC2_CONTROL_PITCH)
 442                         attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
 443         }
 444
 445         return attributes;
 446 }
 447
 448 /* find an input terminal descriptor (either UAC1 or UAC2) with the given
 449  * terminal id
 450  */
 451 static void *
 452 snd_usb_find_input_terminal_descriptor(struct usb_host_interface *ctrl_iface,
 453                                                int terminal_id)
 454 {
 455         struct uac2_input_terminal_descriptor *term = NULL;
 456
 457         while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
 458                                                ctrl_iface->extralen,
 459                                                term, UAC_INPUT_TERMINAL))) {
 460                 if (term->bTerminalID == terminal_id)
 461                         return term;
 462         }
 463
 464         return NULL;
 465 }
 466
 467 static struct uac2_output_terminal_descriptor *
 468         snd_usb_find_output_terminal_descriptor(struct usb_host_interface *ctrl_iface,
 469                                                 int terminal_id)
 470 {
 471         struct uac2_output_terminal_descriptor *term = NULL;
 472
 473         while ((term = snd_usb_find_csint_desc(ctrl_iface->extra,
 474                                                ctrl_iface->extralen,
 475                                                term, UAC_OUTPUT_TERMINAL))) {
 476                 if (term->bTerminalID == terminal_id)
 477                         return term;
 478         }
 479
 480         return NULL;
 481 }
 482
 483 int snd_usb_parse_audio_interface(struct snd_usb_audio *chip, int iface_no)
 484 {
 485         struct usb_device *dev;
 486         struct usb_interface *iface;
 487         struct usb_host_interface *alts;
 488         struct usb_interface_descriptor *altsd;
 489         int i, altno, err, stream;
 490         unsigned int format = 0, num_channels = 0;
 491         struct audioformat *fp = NULL;
 492         int num, protocol, clock = 0;
 493         struct uac_format_type_i_continuous_descriptor *fmt;
 494         unsigned int chconfig;
 495
 496         dev = chip->dev;
 497
 498         /* parse the interface's altsettings */
 499         iface = usb_ifnum_to_if(dev, iface_no);
 500
 501         num = iface->num_altsetting;
 502
 503         /*
 504          * Dallas DS4201 workaround: It presents 5 altsettings, but the last
 505          * one misses syncpipe, and does not produce any sound.
 506          */
 507         if (chip->usb_id == USB_ID(0x04fa, 0x4201))
 508                 num = 4;
 509
 510         for (i = 0; i < num; i++) {
 511                 alts = &iface->altsetting[i];
 512                 altsd = get_iface_desc(alts);
 513                 protocol = altsd->bInterfaceProtocol;
 514                 /* skip invalid one */
 515                 if (((altsd->bInterfaceClass != USB_CLASS_AUDIO ||
 516                       (altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING &&
 517                        altsd->bInterfaceSubClass != USB_SUBCLASS_VENDOR_SPEC)) &&
 518                      altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 519                     altsd->bNumEndpoints < 1 ||
 520                     le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) == 0)
 521                         continue;
 522                 /* must be isochronous */
 523                 if ((get_endpoint(alts, 0)->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) !=
 524                     USB_ENDPOINT_XFER_ISOC)
 525                         continue;
 526                 /* check direction */
 527                 stream = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN) ?
 528                         SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
 529                 altno = altsd->bAlternateSetting;
 530
 531                 if (snd_usb_apply_interface_quirk(chip, iface_no, altno))
 532                         continue;
 533
 534                 /*
 535                  * Roland audio streaming interfaces are marked with protocols
 536                  * 0/1/2, but are UAC 1 compatible.
 537                  */
 538                 if (USB_ID_VENDOR(chip->usb_id) == 0x0582 &&
 539                     altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 540                     protocol <= 2)
 541                         protocol = UAC_VERSION_1;
 542
 543                 chconfig = 0;
 544                 /* get audio formats */
 545                 switch (protocol) {
 546                 default:
 547                         dev_dbg(&dev->dev, "%u:%d: unknown interface protocol %#02x, assuming v1\n",
 548                                 iface_no, altno, protocol);
 549                         protocol = UAC_VERSION_1;
 550                         /* fall through */
 551
 552                 case UAC_VERSION_1: {
 553                         struct uac1_as_header_descriptor *as =
 554                                 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
 555                         struct uac_input_terminal_descriptor *iterm;
 556
 557                         if (!as) {
 558                                 dev_err(&dev->dev,
 559                                         "%u:%d : UAC_AS_GENERAL descriptor not found\n",
 560                                         iface_no, altno);
 561                                 continue;
 562                         }
 563
 564                         if (as->bLength < sizeof(*as)) {
 565                                 dev_err(&dev->dev,
 566                                         "%u:%d : invalid UAC_AS_GENERAL desc\n",
 567                                         iface_no, altno);
 568                                 continue;
 569                         }
 570
 571                         format = le16_to_cpu(as->wFormatTag); /* remember the format value */
 572
 573                         iterm = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
 574                                                                        as->bTerminalLink);
 575                         if (iterm) {
 576                                 num_channels = iterm->bNrChannels;
 577                                 chconfig = le16_to_cpu(iterm->wChannelConfig);
 578                         }
 579
 580                         break;
 581                 }
 582
 583                 case UAC_VERSION_2: {
 584                         struct uac2_input_terminal_descriptor *input_term;
 585                         struct uac2_output_terminal_descriptor *output_term;
 586                         struct uac2_as_header_descriptor *as =
 587                                 snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_AS_GENERAL);
 588
 589                         if (!as) {
 590                                 dev_err(&dev->dev,
 591                                         "%u:%d : UAC_AS_GENERAL descriptor not found\n",
 592                                         iface_no, altno);
 593                                 continue;
 594                         }
 595
 596                         if (as->bLength < sizeof(*as)) {
 597                                 dev_err(&dev->dev,
 598                                         "%u:%d : invalid UAC_AS_GENERAL desc\n",
 599                                         iface_no, altno);
 600                                 continue;
 601                         }
 602
 603                         num_channels = as->bNrChannels;
 604                         format = le32_to_cpu(as->bmFormats);
 605                         chconfig = le32_to_cpu(as->bmChannelConfig);
 606
 607                         /* lookup the terminal associated to this interface
 608                          * to extract the clock */
 609                         input_term = snd_usb_find_input_terminal_descriptor(chip->ctrl_intf,
 610                                                                             as->bTerminalLink);
 611                         if (input_term) {
 612                                 clock = input_term->bCSourceID;
 613                                 if (!chconfig && (num_channels == input_term->bNrChannels))
 614                                         chconfig = le32_to_cpu(input_term->bmChannelConfig);
 615                                 break;
 616                         }
 617
 618                         output_term = snd_usb_find_output_terminal_descriptor(chip->ctrl_intf,
 619                                                                               as->bTerminalLink);
 620                         if (output_term) {
 621                                 clock = output_term->bCSourceID;
 622                                 break;
 623                         }
 624
 625                         dev_err(&dev->dev,
 626                                 "%u:%d : bogus bTerminalLink %d\n",
 627                                 iface_no, altno, as->bTerminalLink);
 628                         continue;
 629                 }
 630                 }
 631
 632                 /* get format type */
 633                 fmt = snd_usb_find_csint_desc(alts->extra, alts->extralen, NULL, UAC_FORMAT_TYPE);
 634                 if (!fmt) {
 635                         dev_err(&dev->dev,
 636                                 "%u:%d : no UAC_FORMAT_TYPE desc\n",
 637                                 iface_no, altno);
 638                         continue;
 639                 }
 640                 if (((protocol == UAC_VERSION_1) && (fmt->bLength < 8)) ||
 641                     ((protocol == UAC_VERSION_2) && (fmt->bLength < 6))) {
 642                         dev_err(&dev->dev,
 643                                 "%u:%d : invalid UAC_FORMAT_TYPE desc\n",
 644                                 iface_no, altno);
 645                         continue;
 646                 }
 647
 648                 /*
 649                  * Blue Microphones workaround: The last altsetting is identical
 650                  * with the previous one, except for a larger packet size, but
 651                  * is actually a mislabeled two-channel setting; ignore it.
 652                  */
 653                 if (fmt->bNrChannels == 1 &&
 654                     fmt->bSubframeSize == 2 &&
 655                     altno == 2 && num == 3 &&
 656                     fp && fp->altsetting == 1 && fp->channels == 1 &&
 657                     fp->formats == SNDRV_PCM_FMTBIT_S16_LE &&
 658                     protocol == UAC_VERSION_1 &&
 659                     le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize) ==
 660                                                         fp->maxpacksize * 2)
 661                         continue;
 662
 663                 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
 664                 if (! fp) {
 665                         dev_err(&dev->dev, "cannot malloc\n");
 666                         return -ENOMEM;
 667                 }
 668
 669                 fp->iface = iface_no;
 670                 fp->altsetting = altno;
 671                 fp->altset_idx = i;
 672                 fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
 673                 fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
 674                 fp->datainterval = snd_usb_parse_datainterval(chip, alts);
 675                 fp->protocol = protocol;
 676                 fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
 677                 fp->channels = num_channels;
 678                 if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
 679                         fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
 680                                         * (fp->maxpacksize & 0x7ff);
 681                 fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
 682                 fp->clock = clock;
 683                 INIT_LIST_HEAD(&fp->list);
 684
 685                 /* some quirks for attributes here */
 686
 687                 switch (chip->usb_id) {
 688                 case USB_ID(0x0a92, 0x0053): /* AudioTrak Optoplay */
 689                         /* Optoplay sets the sample rate attribute although
 690                          * it seems not supporting it in fact.
 691                          */
 692                         fp->attributes &= ~UAC_EP_CS_ATTR_SAMPLE_RATE;
 693                         break;
 694                 case USB_ID(0x041e, 0x3020): /* Creative SB Audigy 2 NX */
 695                 case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
 696                         /* doesn't set the sample rate attribute, but supports it */
 697                         fp->attributes |= UAC_EP_CS_ATTR_SAMPLE_RATE;
 698                         break;
 699                 case USB_ID(0x0763, 0x2001):  /* M-Audio Quattro USB */
 700                 case USB_ID(0x0763, 0x2012):  /* M-Audio Fast Track Pro USB */
 701                 case USB_ID(0x047f, 0x0ca1): /* plantronics headset */
 702                 case USB_ID(0x077d, 0x07af): /* Griffin iMic (note that there is
 703                                                 an older model 77d:223) */
 704                 /*
 705                  * plantronics headset and Griffin iMic have set adaptive-in
 706                  * although it's really not...
 707                  */
 708                         fp->ep_attr &= ~USB_ENDPOINT_SYNCTYPE;
 709                         if (stream == SNDRV_PCM_STREAM_PLAYBACK)
 710                                 fp->ep_attr |= USB_ENDPOINT_SYNC_ADAPTIVE;
 711                         else
 712                                 fp->ep_attr |= USB_ENDPOINT_SYNC_SYNC;
 713                         break;
 714                 }
 715
 716                 /* ok, let's parse further... */
 717                 if (snd_usb_parse_audio_format(chip, fp, format, fmt, stream) < 0) {
 718                         kfree(fp->rate_table);
 719                         kfree(fp);
 720                         fp = NULL;
 721                         continue;
 722                 }
 723
 724                 /* Create chmap */
 725                 if (fp->channels != num_channels)
 726                         chconfig = 0;
 727                 fp->chmap = convert_chmap(fp->channels, chconfig, protocol);
 728
 729                 dev_dbg(&dev->dev, "%u:%d: add audio endpoint %#x\n", iface_no, altno, fp->endpoint);
 730                 err = snd_usb_add_audio_stream(chip, stream, fp);
 731                 if (err < 0) {
 732                         list_del(&fp->list); /* unlink for avoiding double-free */
 733                         kfree(fp->rate_table);
 734                         kfree(fp->chmap);
 735                         kfree(fp);
 736                         return err;
 737                 }
 738                 /* try to set the interface... */
 739                 usb_set_interface(chip->dev, iface_no, altno);
 740                 snd_usb_init_pitch(chip, iface_no, alts, fp);
 741                 snd_usb_init_sample_rate(chip, iface_no, alts, fp, fp->rate_max);
 742         }
 743         return 0;
 744 }
 745