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