sound/usb/card.c

   1 /*
   2  *   (Tentative) USB Audio Driver for ALSA
   3  *
   4  *   Copyright (c) 2002 by Takashi Iwai <[email protected]>
   5  *
   6  *   Many codes borrowed from audio.c by
   7  *          Alan Cox ([email protected])
   8  *          Thomas Sailer ([email protected])
   9  *
  10  *   Audio Class 3.0 support by Ruslan Bilovol <[email protected]>
  11  *
  12  *   This program is free software; you can redistribute it and/or modify
  13  *   it under the terms of the GNU General Public License as published by
  14  *   the Free Software Foundation; either version 2 of the License, or
  15  *   (at your option) any later version.
  16  *
  17  *   This program is distributed in the hope that it will be useful,
  18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *   GNU General Public License for more details.
  21  *
  22  *   You should have received a copy of the GNU General Public License
  23  *   along with this program; if not, write to the Free Software
  24  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  25  *
  26  *
  27  *  NOTES:
  28  *
  29  *   - the linked URBs would be preferred but not used so far because of
  30  *     the instability of unlinking.
  31  *   - type II is not supported properly.  there is no device which supports
  32  *     this type *correctly*.  SB extigy looks as if it supports, but it's
  33  *     indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
  34  */
  35
  36
  37 #include <linux/bitops.h>
  38 #include <linux/init.h>
  39 #include <linux/list.h>
  40 #include <linux/slab.h>
  41 #include <linux/string.h>
  42 #include <linux/ctype.h>
  43 #include <linux/usb.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/mutex.h>
  46 #include <linux/usb/audio.h>
  47 #include <linux/usb/audio-v2.h>
  48 #include <linux/usb/audio-v3.h>
  49 #include <linux/module.h>
  50
  51 #include <sound/control.h>
  52 #include <sound/core.h>
  53 #include <sound/info.h>
  54 #include <sound/pcm.h>
  55 #include <sound/pcm_params.h>
  56 #include <sound/initval.h>
  57
  58 #include "usbaudio.h"
  59 #include "card.h"
  60 #include "midi.h"
  61 #include "mixer.h"
  62 #include "proc.h"
  63 #include "quirks.h"
  64 #include "endpoint.h"
  65 #include "helper.h"
  66 #include "debug.h"
  67 #include "pcm.h"
  68 #include "format.h"
  69 #include "power.h"
  70 #include "stream.h"
  71
  72 MODULE_AUTHOR("Takashi Iwai <[email protected]>");
  73 MODULE_DESCRIPTION("USB Audio");
  74 MODULE_LICENSE("GPL");
  75 MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
  76
  77
  78 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  79 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  80 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
  81 /* Vendor/product IDs for this card */
  82 static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  83 static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  84 static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
  85 static bool ignore_ctl_error;
  86 static bool autoclock = true;
  87 static char *quirk_alias[SNDRV_CARDS];
  88
  89 bool snd_usb_use_vmalloc = true;
  90
  91 module_param_array(index, int, NULL, 0444);
  92 MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
  93 module_param_array(id, charp, NULL, 0444);
  94 MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
  95 module_param_array(enable, bool, NULL, 0444);
  96 MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
  97 module_param_array(vid, int, NULL, 0444);
  98 MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
  99 module_param_array(pid, int, NULL, 0444);
 100 MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
 101 module_param_array(device_setup, int, NULL, 0444);
 102 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
 103 module_param(ignore_ctl_error, bool, 0444);
 104 MODULE_PARM_DESC(ignore_ctl_error,
 105                  "Ignore errors from USB controller for mixer interfaces.");
 106 module_param(autoclock, bool, 0444);
 107 MODULE_PARM_DESC(autoclock, "Enable auto-clock selection for UAC2 devices (default: yes).");
 108 module_param_array(quirk_alias, charp, NULL, 0444);
 109 MODULE_PARM_DESC(quirk_alias, "Quirk aliases, e.g. 0123abcd:5678beef.");
 110 module_param_named(use_vmalloc, snd_usb_use_vmalloc, bool, 0444);
 111 MODULE_PARM_DESC(use_vmalloc, "Use vmalloc for PCM intermediate buffers (default: yes).");
 112
 113 /*
 114  * we keep the snd_usb_audio_t instances by ourselves for merging
 115  * the all interfaces on the same card as one sound device.
 116  */
 117
 118 static DEFINE_MUTEX(register_mutex);
 119 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
 120 static struct usb_driver usb_audio_driver;
 121
 122 /*
 123  * disconnect streams
 124  * called from usb_audio_disconnect()
 125  */
 126 static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
 127 {
 128         int idx;
 129         struct snd_usb_substream *subs;
 130
 131         for (idx = 0; idx < 2; idx++) {
 132                 subs = &as->substream[idx];
 133                 if (!subs->num_formats)
 134                         continue;
 135                 subs->interface = -1;
 136                 subs->data_endpoint = NULL;
 137                 subs->sync_endpoint = NULL;
 138         }
 139 }
 140
 141 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
 142 {
 143         struct usb_device *dev = chip->dev;
 144         struct usb_host_interface *alts;
 145         struct usb_interface_descriptor *altsd;
 146         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
 147
 148         if (!iface) {
 149                 dev_err(&dev->dev, "%u:%d : does not exist\n",
 150                         ctrlif, interface);
 151                 return -EINVAL;
 152         }
 153
 154         alts = &iface->altsetting[0];
 155         altsd = get_iface_desc(alts);
 156
 157         /*
 158          * Android with both accessory and audio interfaces enabled gets the
 159          * interface numbers wrong.
 160          */
 161         if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
 162              chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
 163             interface == 0 &&
 164             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 165             altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
 166                 interface = 2;
 167                 iface = usb_ifnum_to_if(dev, interface);
 168                 if (!iface)
 169                         return -EINVAL;
 170                 alts = &iface->altsetting[0];
 171                 altsd = get_iface_desc(alts);
 172         }
 173
 174         if (usb_interface_claimed(iface)) {
 175                 dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
 176                         ctrlif, interface);
 177                 return -EINVAL;
 178         }
 179
 180         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 181              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 182             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
 183                 int err = __snd_usbmidi_create(chip->card, iface,
 184                                              &chip->midi_list, NULL,
 185                                              chip->usb_id);
 186                 if (err < 0) {
 187                         dev_err(&dev->dev,
 188                                 "%u:%d: cannot create sequencer device\n",
 189                                 ctrlif, interface);
 190                         return -EINVAL;
 191                 }
 192                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 193
 194                 return 0;
 195         }
 196
 197         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
 198              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 199             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
 200                 dev_dbg(&dev->dev,
 201                         "%u:%d: skipping non-supported interface %d\n",
 202                         ctrlif, interface, altsd->bInterfaceClass);
 203                 /* skip non-supported classes */
 204                 return -EINVAL;
 205         }
 206
 207         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
 208                 dev_err(&dev->dev, "low speed audio streaming not supported\n");
 209                 return -EINVAL;
 210         }
 211
 212         if (! snd_usb_parse_audio_interface(chip, interface)) {
 213                 usb_set_interface(dev, interface, 0); /* reset the current interface */
 214                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 215         }
 216
 217         return 0;
 218 }
 219
 220 /*
 221  * parse audio control descriptor and create pcm/midi streams
 222  */
 223 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 224 {
 225         struct usb_device *dev = chip->dev;
 226         struct usb_host_interface *host_iface;
 227         struct usb_interface_descriptor *altsd;
 228         int i, protocol;
 229
 230         /* find audiocontrol interface */
 231         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
 232         altsd = get_iface_desc(host_iface);
 233         protocol = altsd->bInterfaceProtocol;
 234
 235         switch (protocol) {
 236         default:
 237                 dev_warn(&dev->dev,
 238                          "unknown interface protocol %#02x, assuming v1\n",
 239                          protocol);
 240                 /* fall through */
 241
 242         case UAC_VERSION_1: {
 243                 struct uac1_ac_header_descriptor *h1;
 244                 int rest_bytes;
 245
 246                 h1 = snd_usb_find_csint_desc(host_iface->extra,
 247                                                          host_iface->extralen,
 248                                                          NULL, UAC_HEADER);
 249                 if (!h1) {
 250                         dev_err(&dev->dev, "cannot find UAC_HEADER\n");
 251                         return -EINVAL;
 252                 }
 253
 254                 rest_bytes = (void *)(host_iface->extra +
 255                                 host_iface->extralen) - (void *)h1;
 256
 257                 /* just to be sure -- this shouldn't hit at all */
 258                 if (rest_bytes <= 0) {
 259                         dev_err(&dev->dev, "invalid control header\n");
 260                         return -EINVAL;
 261                 }
 262
 263                 if (rest_bytes < sizeof(*h1)) {
 264                         dev_err(&dev->dev, "too short v1 buffer descriptor\n");
 265                         return -EINVAL;
 266                 }
 267
 268                 if (!h1->bInCollection) {
 269                         dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
 270                         return -EINVAL;
 271                 }
 272
 273                 if (rest_bytes < h1->bLength) {
 274                         dev_err(&dev->dev, "invalid buffer length (v1)\n");
 275                         return -EINVAL;
 276                 }
 277
 278                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
 279                         dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
 280                         return -EINVAL;
 281                 }
 282
 283                 for (i = 0; i < h1->bInCollection; i++)
 284                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
 285
 286                 break;
 287         }
 288
 289         case UAC_VERSION_2:
 290         case UAC_VERSION_3: {
 291                 struct usb_interface_assoc_descriptor *assoc =
 292                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
 293
 294                 if (!assoc) {
 295                         /*
 296                          * Firmware writers cannot count to three.  So to find
 297                          * the IAD on the NuForce UDH-100, also check the next
 298                          * interface.
 299                          */
 300                         struct usb_interface *iface =
 301                                 usb_ifnum_to_if(dev, ctrlif + 1);
 302                         if (iface &&
 303                             iface->intf_assoc &&
 304                             iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
 305                             iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
 306                                 assoc = iface->intf_assoc;
 307                 }
 308
 309                 if (!assoc) {
 310                         dev_err(&dev->dev, "Audio class v2/v3 interfaces need an interface association\n");
 311                         return -EINVAL;
 312                 }
 313
 314                 if (protocol == UAC_VERSION_3) {
 315                         int badd = assoc->bFunctionSubClass;
 316
 317                         if (badd != UAC3_FUNCTION_SUBCLASS_FULL_ADC_3_0 &&
 318                             (badd < UAC3_FUNCTION_SUBCLASS_GENERIC_IO ||
 319                              badd > UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE)) {
 320                                 dev_err(&dev->dev,
 321                                         "Unsupported UAC3 BADD profile\n");
 322                                 return -EINVAL;
 323                         }
 324
 325                         chip->badd_profile = badd;
 326                 }
 327
 328                 for (i = 0; i < assoc->bInterfaceCount; i++) {
 329                         int intf = assoc->bFirstInterface + i;
 330
 331                         if (intf != ctrlif)
 332                                 snd_usb_create_stream(chip, ctrlif, intf);
 333                 }
 334
 335                 break;
 336         }
 337         }
 338
 339         return 0;
 340 }
 341
 342 /*
 343  * free the chip instance
 344  *
 345  * here we have to do not much, since pcm and controls are already freed
 346  *
 347  */
 348
 349 static void snd_usb_audio_free(struct snd_card *card)
 350 {
 351         struct snd_usb_audio *chip = card->private_data;
 352         struct snd_usb_endpoint *ep, *n;
 353
 354         list_for_each_entry_safe(ep, n, &chip->ep_list, list)
 355                 snd_usb_endpoint_free(ep);
 356
 357         mutex_destroy(&chip->mutex);
 358         if (!atomic_read(&chip->shutdown))
 359                 dev_set_drvdata(&chip->dev->dev, NULL);
 360 }
 361
 362 static void usb_audio_make_shortname(struct usb_device *dev,
 363                                      struct snd_usb_audio *chip,
 364                                      const struct snd_usb_audio_quirk *quirk)
 365 {
 366         struct snd_card *card = chip->card;
 367
 368         if (quirk && quirk->product_name && *quirk->product_name) {
 369                 strlcpy(card->shortname, quirk->product_name,
 370                         sizeof(card->shortname));
 371                 return;
 372         }
 373
 374         /* retrieve the device string as shortname */
 375         if (!dev->descriptor.iProduct ||
 376             usb_string(dev, dev->descriptor.iProduct,
 377                        card->shortname, sizeof(card->shortname)) <= 0) {
 378                 /* no name available from anywhere, so use ID */
 379                 sprintf(card->shortname, "USB Device %#04x:%#04x",
 380                         USB_ID_VENDOR(chip->usb_id),
 381                         USB_ID_PRODUCT(chip->usb_id));
 382         }
 383
 384         strim(card->shortname);
 385 }
 386
 387 static void usb_audio_make_longname(struct usb_device *dev,
 388                                     struct snd_usb_audio *chip,
 389                                     const struct snd_usb_audio_quirk *quirk)
 390 {
 391         struct snd_card *card = chip->card;
 392         int len;
 393
 394         /* shortcut - if any pre-defined string is given, use it */
 395         if (quirk && quirk->profile_name && *quirk->profile_name) {
 396                 strlcpy(card->longname, quirk->profile_name,
 397                         sizeof(card->longname));
 398                 return;
 399         }
 400
 401         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
 402                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
 403         } else {
 404                 /* retrieve the vendor and device strings as longname */
 405                 if (dev->descriptor.iManufacturer)
 406                         len = usb_string(dev, dev->descriptor.iManufacturer,
 407                                          card->longname, sizeof(card->longname));
 408                 else
 409                         len = 0;
 410                 /* we don't really care if there isn't any vendor string */
 411         }
 412         if (len > 0) {
 413                 strim(card->longname);
 414                 if (*card->longname)
 415                         strlcat(card->longname, " ", sizeof(card->longname));
 416         }
 417
 418         strlcat(card->longname, card->shortname, sizeof(card->longname));
 419
 420         len = strlcat(card->longname, " at ", sizeof(card->longname));
 421
 422         if (len < sizeof(card->longname))
 423                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
 424
 425         switch (snd_usb_get_speed(dev)) {
 426         case USB_SPEED_LOW:
 427                 strlcat(card->longname, ", low speed", sizeof(card->longname));
 428                 break;
 429         case USB_SPEED_FULL:
 430                 strlcat(card->longname, ", full speed", sizeof(card->longname));
 431                 break;
 432         case USB_SPEED_HIGH:
 433                 strlcat(card->longname, ", high speed", sizeof(card->longname));
 434                 break;
 435         case USB_SPEED_SUPER:
 436                 strlcat(card->longname, ", super speed", sizeof(card->longname));
 437                 break;
 438         case USB_SPEED_SUPER_PLUS:
 439                 strlcat(card->longname, ", super speed plus", sizeof(card->longname));
 440                 break;
 441         default:
 442                 break;
 443         }
 444 }
 445
 446 /*
 447  * create a chip instance and set its names.
 448  */
 449 static int snd_usb_audio_create(struct usb_interface *intf,
 450                                 struct usb_device *dev, int idx,
 451                                 const struct snd_usb_audio_quirk *quirk,
 452                                 unsigned int usb_id,
 453                                 struct snd_usb_audio **rchip)
 454 {
 455         struct snd_card *card;
 456         struct snd_usb_audio *chip;
 457         int err;
 458         char component[14];
 459
 460         *rchip = NULL;
 461
 462         switch (snd_usb_get_speed(dev)) {
 463         case USB_SPEED_LOW:
 464         case USB_SPEED_FULL:
 465         case USB_SPEED_HIGH:
 466         case USB_SPEED_WIRELESS:
 467         case USB_SPEED_SUPER:
 468         case USB_SPEED_SUPER_PLUS:
 469                 break;
 470         default:
 471                 dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
 472                 return -ENXIO;
 473         }
 474
 475         err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
 476                            sizeof(*chip), &card);
 477         if (err < 0) {
 478                 dev_err(&dev->dev, "cannot create card instance %d\n", idx);
 479                 return err;
 480         }
 481
 482         chip = card->private_data;
 483         mutex_init(&chip->mutex);
 484         init_waitqueue_head(&chip->shutdown_wait);
 485         chip->index = idx;
 486         chip->dev = dev;
 487         chip->card = card;
 488         chip->setup = device_setup[idx];
 489         chip->autoclock = autoclock;
 490         atomic_set(&chip->active, 1); /* avoid autopm during probing */
 491         atomic_set(&chip->usage_count, 0);
 492         atomic_set(&chip->shutdown, 0);
 493
 494         chip->usb_id = usb_id;
 495         INIT_LIST_HEAD(&chip->pcm_list);
 496         INIT_LIST_HEAD(&chip->ep_list);
 497         INIT_LIST_HEAD(&chip->midi_list);
 498         INIT_LIST_HEAD(&chip->mixer_list);
 499
 500         card->private_free = snd_usb_audio_free;
 501
 502         strcpy(card->driver, "USB-Audio");
 503         sprintf(component, "USB%04x:%04x",
 504                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
 505         snd_component_add(card, component);
 506
 507         usb_audio_make_shortname(dev, chip, quirk);
 508         usb_audio_make_longname(dev, chip, quirk);
 509
 510         snd_usb_audio_create_proc(chip);
 511
 512         *rchip = chip;
 513         return 0;
 514 }
 515
 516 /* look for a matching quirk alias id */
 517 static bool get_alias_id(struct usb_device *dev, unsigned int *id)
 518 {
 519         int i;
 520         unsigned int src, dst;
 521
 522         for (i = 0; i < ARRAY_SIZE(quirk_alias); i++) {
 523                 if (!quirk_alias[i] ||
 524                     sscanf(quirk_alias[i], "%x:%x", &src, &dst) != 2 ||
 525                     src != *id)
 526                         continue;
 527                 dev_info(&dev->dev,
 528                          "device (%04x:%04x): applying quirk alias %04x:%04x\n",
 529                          USB_ID_VENDOR(*id), USB_ID_PRODUCT(*id),
 530                          USB_ID_VENDOR(dst), USB_ID_PRODUCT(dst));
 531                 *id = dst;
 532                 return true;
 533         }
 534
 535         return false;
 536 }
 537
 538 static const struct usb_device_id usb_audio_ids[]; /* defined below */
 539
 540 /* look for the corresponding quirk */
 541 static const struct snd_usb_audio_quirk *
 542 get_alias_quirk(struct usb_device *dev, unsigned int id)
 543 {
 544         const struct usb_device_id *p;
 545
 546         for (p = usb_audio_ids; p->match_flags; p++) {
 547                 /* FIXME: this checks only vendor:product pair in the list */
 548                 if ((p->match_flags & USB_DEVICE_ID_MATCH_DEVICE) ==
 549                     USB_DEVICE_ID_MATCH_DEVICE &&
 550                     p->idVendor == USB_ID_VENDOR(id) &&
 551                     p->idProduct == USB_ID_PRODUCT(id))
 552                         return (const struct snd_usb_audio_quirk *)p->driver_info;
 553         }
 554
 555         return NULL;
 556 }
 557
 558 /*
 559  * probe the active usb device
 560  *
 561  * note that this can be called multiple times per a device, when it
 562  * includes multiple audio control interfaces.
 563  *
 564  * thus we check the usb device pointer and creates the card instance
 565  * only at the first time.  the successive calls of this function will
 566  * append the pcm interface to the corresponding card.
 567  */
 568 static int usb_audio_probe(struct usb_interface *intf,
 569                            const struct usb_device_id *usb_id)
 570 {
 571         struct usb_device *dev = interface_to_usbdev(intf);
 572         const struct snd_usb_audio_quirk *quirk =
 573                 (const struct snd_usb_audio_quirk *)usb_id->driver_info;
 574         struct snd_usb_audio *chip;
 575         int i, err;
 576         struct usb_host_interface *alts;
 577         int ifnum;
 578         u32 id;
 579
 580         alts = &intf->altsetting[0];
 581         ifnum = get_iface_desc(alts)->bInterfaceNumber;
 582         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 583                     le16_to_cpu(dev->descriptor.idProduct));
 584         if (get_alias_id(dev, &id))
 585                 quirk = get_alias_quirk(dev, id);
 586         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
 587                 return -ENXIO;
 588
 589         err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
 590         if (err < 0)
 591                 return err;
 592
 593         /*
 594          * found a config.  now register to ALSA
 595          */
 596
 597         /* check whether it's already registered */
 598         chip = NULL;
 599         mutex_lock(&register_mutex);
 600         for (i = 0; i < SNDRV_CARDS; i++) {
 601                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
 602                         if (atomic_read(&usb_chip[i]->shutdown)) {
 603                                 dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
 604                                 err = -EIO;
 605                                 goto __error;
 606                         }
 607                         chip = usb_chip[i];
 608                         atomic_inc(&chip->active); /* avoid autopm */
 609                         break;
 610                 }
 611         }
 612         if (! chip) {
 613                 /* it's a fresh one.
 614                  * now look for an empty slot and create a new card instance
 615                  */
 616                 for (i = 0; i < SNDRV_CARDS; i++)
 617                         if (!usb_chip[i] &&
 618                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
 619                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
 620                                 if (enable[i]) {
 621                                         err = snd_usb_audio_create(intf, dev, i, quirk,
 622                                                                    id, &chip);
 623                                         if (err < 0)
 624                                                 goto __error;
 625                                         chip->pm_intf = intf;
 626                                         break;
 627                                 } else if (vid[i] != -1 || pid[i] != -1) {
 628                                         dev_info(&dev->dev,
 629                                                  "device (%04x:%04x) is disabled\n",
 630                                                  USB_ID_VENDOR(id),
 631                                                  USB_ID_PRODUCT(id));
 632                                         err = -ENOENT;
 633                                         goto __error;
 634                                 }
 635                         }
 636                 if (!chip) {
 637                         dev_err(&dev->dev, "no available usb audio device\n");
 638                         err = -ENODEV;
 639                         goto __error;
 640                 }
 641         }
 642         dev_set_drvdata(&dev->dev, chip);
 643
 644         /*
 645          * For devices with more than one control interface, we assume the
 646          * first contains the audio controls. We might need a more specific
 647          * check here in the future.
 648          */
 649         if (!chip->ctrl_intf)
 650                 chip->ctrl_intf = alts;
 651
 652         chip->txfr_quirk = 0;
 653         err = 1; /* continue */
 654         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
 655                 /* need some special handlings */
 656                 err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk);
 657                 if (err < 0)
 658                         goto __error;
 659         }
 660
 661         if (err > 0) {
 662                 /* create normal USB audio interfaces */
 663                 err = snd_usb_create_streams(chip, ifnum);
 664                 if (err < 0)
 665                         goto __error;
 666                 err = snd_usb_create_mixer(chip, ifnum, ignore_ctl_error);
 667                 if (err < 0)
 668                         goto __error;
 669         }
 670
 671         /* we are allowed to call snd_card_register() many times */
 672         err = snd_card_register(chip->card);
 673         if (err < 0)
 674                 goto __error;
 675
 676         usb_chip[chip->index] = chip;
 677         chip->num_interfaces++;
 678         usb_set_intfdata(intf, chip);
 679         atomic_dec(&chip->active);
 680         mutex_unlock(&register_mutex);
 681         return 0;
 682
 683  __error:
 684         if (chip) {
 685                 if (!chip->num_interfaces)
 686                         snd_card_free(chip->card);
 687                 atomic_dec(&chip->active);
 688         }
 689         mutex_unlock(&register_mutex);
 690         return err;
 691 }
 692
 693 /*
 694  * we need to take care of counter, since disconnection can be called also
 695  * many times as well as usb_audio_probe().
 696  */
 697 static void usb_audio_disconnect(struct usb_interface *intf)
 698 {
 699         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 700         struct snd_card *card;
 701         struct list_head *p;
 702
 703         if (chip == (void *)-1L)
 704                 return;
 705
 706         card = chip->card;
 707
 708         mutex_lock(&register_mutex);
 709         if (atomic_inc_return(&chip->shutdown) == 1) {
 710                 struct snd_usb_stream *as;
 711                 struct snd_usb_endpoint *ep;
 712                 struct usb_mixer_interface *mixer;
 713
 714                 /* wait until all pending tasks done;
 715                  * they are protected by snd_usb_lock_shutdown()
 716                  */
 717                 wait_event(chip->shutdown_wait,
 718                            !atomic_read(&chip->usage_count));
 719                 snd_card_disconnect(card);
 720                 /* release the pcm resources */
 721                 list_for_each_entry(as, &chip->pcm_list, list) {
 722                         snd_usb_stream_disconnect(as);
 723                 }
 724                 /* release the endpoint resources */
 725                 list_for_each_entry(ep, &chip->ep_list, list) {
 726                         snd_usb_endpoint_release(ep);
 727                 }
 728                 /* release the midi resources */
 729                 list_for_each(p, &chip->midi_list) {
 730                         snd_usbmidi_disconnect(p);
 731                 }
 732                 /* release mixer resources */
 733                 list_for_each_entry(mixer, &chip->mixer_list, list) {
 734                         snd_usb_mixer_disconnect(mixer);
 735                 }
 736         }
 737
 738         chip->num_interfaces--;
 739         if (chip->num_interfaces <= 0) {
 740                 usb_chip[chip->index] = NULL;
 741                 mutex_unlock(&register_mutex);
 742                 snd_card_free_when_closed(card);
 743         } else {
 744                 mutex_unlock(&register_mutex);
 745         }
 746 }
 747
 748 /* lock the shutdown (disconnect) task and autoresume */
 749 int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
 750 {
 751         int err;
 752
 753         atomic_inc(&chip->usage_count);
 754         if (atomic_read(&chip->shutdown)) {
 755                 err = -EIO;
 756                 goto error;
 757         }
 758         err = snd_usb_autoresume(chip);
 759         if (err < 0)
 760                 goto error;
 761         return 0;
 762
 763  error:
 764         if (atomic_dec_and_test(&chip->usage_count))
 765                 wake_up(&chip->shutdown_wait);
 766         return err;
 767 }
 768
 769 /* autosuspend and unlock the shutdown */
 770 void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
 771 {
 772         snd_usb_autosuspend(chip);
 773         if (atomic_dec_and_test(&chip->usage_count))
 774                 wake_up(&chip->shutdown_wait);
 775 }
 776
 777 #ifdef CONFIG_PM
 778
 779 int snd_usb_autoresume(struct snd_usb_audio *chip)
 780 {
 781         if (atomic_read(&chip->shutdown))
 782                 return -EIO;
 783         if (atomic_inc_return(&chip->active) == 1)
 784                 return usb_autopm_get_interface(chip->pm_intf);
 785         return 0;
 786 }
 787
 788 void snd_usb_autosuspend(struct snd_usb_audio *chip)
 789 {
 790         if (atomic_read(&chip->shutdown))
 791                 return;
 792         if (atomic_dec_and_test(&chip->active))
 793                 usb_autopm_put_interface(chip->pm_intf);
 794 }
 795
 796 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 797 {
 798         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 799         struct snd_usb_stream *as;
 800         struct usb_mixer_interface *mixer;
 801         struct list_head *p;
 802
 803         if (chip == (void *)-1L)
 804                 return 0;
 805
 806         chip->autosuspended = !!PMSG_IS_AUTO(message);
 807         if (!chip->autosuspended)
 808                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
 809         if (!chip->num_suspended_intf++) {
 810                 list_for_each_entry(as, &chip->pcm_list, list) {
 811                         snd_pcm_suspend_all(as->pcm);
 812                         snd_usb_pcm_suspend(as);
 813                         as->substream[0].need_setup_ep =
 814                                 as->substream[1].need_setup_ep = true;
 815                 }
 816                 list_for_each(p, &chip->midi_list)
 817                         snd_usbmidi_suspend(p);
 818                 list_for_each_entry(mixer, &chip->mixer_list, list)
 819                         snd_usb_mixer_suspend(mixer);
 820         }
 821
 822         return 0;
 823 }
 824
 825 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
 826 {
 827         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 828         struct snd_usb_stream *as;
 829         struct usb_mixer_interface *mixer;
 830         struct list_head *p;
 831         int err = 0;
 832
 833         if (chip == (void *)-1L)
 834                 return 0;
 835         if (--chip->num_suspended_intf)
 836                 return 0;
 837
 838         atomic_inc(&chip->active); /* avoid autopm */
 839
 840         list_for_each_entry(as, &chip->pcm_list, list) {
 841                 err = snd_usb_pcm_resume(as);
 842                 if (err < 0)
 843                         goto err_out;
 844         }
 845
 846         /*
 847          * ALSA leaves material resumption to user space
 848          * we just notify and restart the mixers
 849          */
 850         list_for_each_entry(mixer, &chip->mixer_list, list) {
 851                 err = snd_usb_mixer_resume(mixer, reset_resume);
 852                 if (err < 0)
 853                         goto err_out;
 854         }
 855
 856         list_for_each(p, &chip->midi_list) {
 857                 snd_usbmidi_resume(p);
 858         }
 859
 860         if (!chip->autosuspended)
 861                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
 862         chip->autosuspended = 0;
 863
 864 err_out:
 865         atomic_dec(&chip->active); /* allow autopm after this point */
 866         return err;
 867 }
 868
 869 static int usb_audio_resume(struct usb_interface *intf)
 870 {
 871         return __usb_audio_resume(intf, false);
 872 }
 873
 874 static int usb_audio_reset_resume(struct usb_interface *intf)
 875 {
 876         return __usb_audio_resume(intf, true);
 877 }
 878 #else
 879 #define usb_audio_suspend       NULL
 880 #define usb_audio_resume        NULL
 881 #define usb_audio_reset_resume  NULL
 882 #endif          /* CONFIG_PM */
 883
 884 static const struct usb_device_id usb_audio_ids [] = {
 885 #include "quirks-table.h"
 886     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
 887       .bInterfaceClass = USB_CLASS_AUDIO,
 888       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
 889     { }                                         /* Terminating entry */
 890 };
 891 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
 892
 893 /*
 894  * entry point for linux usb interface
 895  */
 896
 897 static struct usb_driver usb_audio_driver = {
 898         .name =         "snd-usb-audio",
 899         .probe =        usb_audio_probe,
 900         .disconnect =   usb_audio_disconnect,
 901         .suspend =      usb_audio_suspend,
 902         .resume =       usb_audio_resume,
 903         .reset_resume = usb_audio_reset_resume,
 904         .id_table =     usb_audio_ids,
 905         .supports_autosuspend = 1,
 906 };
 907
 908 module_usb_driver(usb_audio_driver);