sound/usb/card.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   (Tentative) USB Audio Driver for ALSA
   4  *
   5  *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
   6  *
   7  *   Many codes borrowed from audio.c by
   8  *          Alan Cox (alan@lxorguk.ukuu.org.uk)
   9  *          Thomas Sailer (sailer@ife.ee.ethz.ch)
  10  *
  11  *   Audio Class 3.0 support by Ruslan Bilovol <ruslan.bilovol@gmail.com>
  12  *
  13  *  NOTES:
  14  *
  15  *   - the linked URBs would be preferred but not used so far because of
  16  *     the instability of unlinking.
  17  *   - type II is not supported properly.  there is no device which supports
  18  *     this type *correctly*.  SB extigy looks as if it supports, but it's
  19  *     indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
  20  */
  21
  22
  23 #include <linux/bitops.h>
  24 #include <linux/init.h>
  25 #include <linux/list.h>
  26 #include <linux/slab.h>
  27 #include <linux/string.h>
  28 #include <linux/ctype.h>
  29 #include <linux/usb.h>
  30 #include <linux/moduleparam.h>
  31 #include <linux/mutex.h>
  32 #include <linux/usb/audio.h>
  33 #include <linux/usb/audio-v2.h>
  34 #include <linux/usb/audio-v3.h>
  35 #include <linux/module.h>
  36
  37 #include <sound/control.h>
  38 #include <sound/core.h>
  39 #include <sound/info.h>
  40 #include <sound/pcm.h>
  41 #include <sound/pcm_params.h>
  42 #include <sound/initval.h>
  43
  44 #include "usbaudio.h"
  45 #include "card.h"
  46 #include "midi.h"
  47 #include "mixer.h"
  48 #include "proc.h"
  49 #include "quirks.h"
  50 #include "endpoint.h"
  51 #include "helper.h"
  52 #include "debug.h"
  53 #include "pcm.h"
  54 #include "format.h"
  55 #include "power.h"
  56 #include "stream.h"
  57 #include "media.h"
  58
  59 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
  60 MODULE_DESCRIPTION("USB Audio");
  61 MODULE_LICENSE("GPL");
  62 MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
  63
  64
  65 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  66 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  67 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
  68 /* Vendor/product IDs for this card */
  69 static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  70 static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  71 static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
  72 static bool ignore_ctl_error;
  73 static bool autoclock = true;
  74 static char *quirk_alias[SNDRV_CARDS];
  75
  76 bool snd_usb_use_vmalloc = true;
  77
  78 module_param_array(index, int, NULL, 0444);
  79 MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
  80 module_param_array(id, charp, NULL, 0444);
  81 MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
  82 module_param_array(enable, bool, NULL, 0444);
  83 MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
  84 module_param_array(vid, int, NULL, 0444);
  85 MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
  86 module_param_array(pid, int, NULL, 0444);
  87 MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
  88 module_param_array(device_setup, int, NULL, 0444);
  89 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
  90 module_param(ignore_ctl_error, bool, 0444);
  91 MODULE_PARM_DESC(ignore_ctl_error,
  92                  "Ignore errors from USB controller for mixer interfaces.");
  93 module_param(autoclock, bool, 0444);
  94 MODULE_PARM_DESC(autoclock, "Enable auto-clock selection for UAC2 devices (default: yes).");
  95 module_param_array(quirk_alias, charp, NULL, 0444);
  96 MODULE_PARM_DESC(quirk_alias, "Quirk aliases, e.g. 0123abcd:5678beef.");
  97 module_param_named(use_vmalloc, snd_usb_use_vmalloc, bool, 0444);
  98 MODULE_PARM_DESC(use_vmalloc, "Use vmalloc for PCM intermediate buffers (default: yes).");
  99
 100 /*
 101  * we keep the snd_usb_audio_t instances by ourselves for merging
 102  * the all interfaces on the same card as one sound device.
 103  */
 104
 105 static DEFINE_MUTEX(register_mutex);
 106 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
 107 static struct usb_driver usb_audio_driver;
 108
 109 /*
 110  * disconnect streams
 111  * called from usb_audio_disconnect()
 112  */
 113 static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
 114 {
 115         int idx;
 116         struct snd_usb_substream *subs;
 117
 118         for (idx = 0; idx < 2; idx++) {
 119                 subs = &as->substream[idx];
 120                 if (!subs->num_formats)
 121                         continue;
 122                 subs->interface = -1;
 123                 subs->data_endpoint = NULL;
 124                 subs->sync_endpoint = NULL;
 125         }
 126 }
 127
 128 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
 129 {
 130         struct usb_device *dev = chip->dev;
 131         struct usb_host_interface *alts;
 132         struct usb_interface_descriptor *altsd;
 133         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
 134
 135         if (!iface) {
 136                 dev_err(&dev->dev, "%u:%d : does not exist\n",
 137                         ctrlif, interface);
 138                 return -EINVAL;
 139         }
 140
 141         alts = &iface->altsetting[0];
 142         altsd = get_iface_desc(alts);
 143
 144         /*
 145          * Android with both accessory and audio interfaces enabled gets the
 146          * interface numbers wrong.
 147          */
 148         if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
 149              chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
 150             interface == 0 &&
 151             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 152             altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
 153                 interface = 2;
 154                 iface = usb_ifnum_to_if(dev, interface);
 155                 if (!iface)
 156                         return -EINVAL;
 157                 alts = &iface->altsetting[0];
 158                 altsd = get_iface_desc(alts);
 159         }
 160
 161         if (usb_interface_claimed(iface)) {
 162                 dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
 163                         ctrlif, interface);
 164                 return -EINVAL;
 165         }
 166
 167         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 168              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 169             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
 170                 int err = __snd_usbmidi_create(chip->card, iface,
 171                                              &chip->midi_list, NULL,
 172                                              chip->usb_id);
 173                 if (err < 0) {
 174                         dev_err(&dev->dev,
 175                                 "%u:%d: cannot create sequencer device\n",
 176                                 ctrlif, interface);
 177                         return -EINVAL;
 178                 }
 179                 return usb_driver_claim_interface(&usb_audio_driver, iface,
 180                                                   USB_AUDIO_IFACE_UNUSED);
 181         }
 182
 183         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
 184              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 185             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
 186                 dev_dbg(&dev->dev,
 187                         "%u:%d: skipping non-supported interface %d\n",
 188                         ctrlif, interface, altsd->bInterfaceClass);
 189                 /* skip non-supported classes */
 190                 return -EINVAL;
 191         }
 192
 193         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
 194                 dev_err(&dev->dev, "low speed audio streaming not supported\n");
 195                 return -EINVAL;
 196         }
 197
 198         if (! snd_usb_parse_audio_interface(chip, interface)) {
 199                 usb_set_interface(dev, interface, 0); /* reset the current interface */
 200                 return usb_driver_claim_interface(&usb_audio_driver, iface,
 201                                                   USB_AUDIO_IFACE_UNUSED);
 202         }
 203
 204         return 0;
 205 }
 206
 207 /*
 208  * parse audio control descriptor and create pcm/midi streams
 209  */
 210 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 211 {
 212         struct usb_device *dev = chip->dev;
 213         struct usb_host_interface *host_iface;
 214         struct usb_interface_descriptor *altsd;
 215         int i, protocol;
 216
 217         /* find audiocontrol interface */
 218         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
 219         altsd = get_iface_desc(host_iface);
 220         protocol = altsd->bInterfaceProtocol;
 221
 222         switch (protocol) {
 223         default:
 224                 dev_warn(&dev->dev,
 225                          "unknown interface protocol %#02x, assuming v1\n",
 226                          protocol);
 227                 /* fall through */
 228
 229         case UAC_VERSION_1: {
 230                 struct uac1_ac_header_descriptor *h1;
 231                 int rest_bytes;
 232
 233                 h1 = snd_usb_find_csint_desc(host_iface->extra,
 234                                                          host_iface->extralen,
 235                                                          NULL, UAC_HEADER);
 236                 if (!h1 || h1->bLength < sizeof(*h1)) {
 237                         dev_err(&dev->dev, "cannot find UAC_HEADER\n");
 238                         return -EINVAL;
 239                 }
 240
 241                 rest_bytes = (void *)(host_iface->extra +
 242                                 host_iface->extralen) - (void *)h1;
 243
 244                 /* just to be sure -- this shouldn't hit at all */
 245                 if (rest_bytes <= 0) {
 246                         dev_err(&dev->dev, "invalid control header\n");
 247                         return -EINVAL;
 248                 }
 249
 250                 if (rest_bytes < sizeof(*h1)) {
 251                         dev_err(&dev->dev, "too short v1 buffer descriptor\n");
 252                         return -EINVAL;
 253                 }
 254
 255                 if (!h1->bInCollection) {
 256                         dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
 257                         return -EINVAL;
 258                 }
 259
 260                 if (rest_bytes < h1->bLength) {
 261                         dev_err(&dev->dev, "invalid buffer length (v1)\n");
 262                         return -EINVAL;
 263                 }
 264
 265                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
 266                         dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
 267                         return -EINVAL;
 268                 }
 269
 270                 for (i = 0; i < h1->bInCollection; i++)
 271                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
 272
 273                 break;
 274         }
 275
 276         case UAC_VERSION_2:
 277         case UAC_VERSION_3: {
 278                 struct usb_interface_assoc_descriptor *assoc =
 279                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
 280
 281                 if (!assoc) {
 282                         /*
 283                          * Firmware writers cannot count to three.  So to find
 284                          * the IAD on the NuForce UDH-100, also check the next
 285                          * interface.
 286                          */
 287                         struct usb_interface *iface =
 288                                 usb_ifnum_to_if(dev, ctrlif + 1);
 289                         if (iface &&
 290                             iface->intf_assoc &&
 291                             iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
 292                             iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
 293                                 assoc = iface->intf_assoc;
 294                 }
 295
 296                 if (!assoc) {
 297                         dev_err(&dev->dev, "Audio class v2/v3 interfaces need an interface association\n");
 298                         return -EINVAL;
 299                 }
 300
 301                 if (protocol == UAC_VERSION_3) {
 302                         int badd = assoc->bFunctionSubClass;
 303
 304                         if (badd != UAC3_FUNCTION_SUBCLASS_FULL_ADC_3_0 &&
 305                             (badd < UAC3_FUNCTION_SUBCLASS_GENERIC_IO ||
 306                              badd > UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE)) {
 307                                 dev_err(&dev->dev,
 308                                         "Unsupported UAC3 BADD profile\n");
 309                                 return -EINVAL;
 310                         }
 311
 312                         chip->badd_profile = badd;
 313                 }
 314
 315                 for (i = 0; i < assoc->bInterfaceCount; i++) {
 316                         int intf = assoc->bFirstInterface + i;
 317
 318                         if (intf != ctrlif)
 319                                 snd_usb_create_stream(chip, ctrlif, intf);
 320                 }
 321
 322                 break;
 323         }
 324         }
 325
 326         return 0;
 327 }
 328
 329 /*
 330  * free the chip instance
 331  *
 332  * here we have to do not much, since pcm and controls are already freed
 333  *
 334  */
 335
 336 static void snd_usb_audio_free(struct snd_card *card)
 337 {
 338         struct snd_usb_audio *chip = card->private_data;
 339         struct snd_usb_endpoint *ep, *n;
 340
 341         list_for_each_entry_safe(ep, n, &chip->ep_list, list)
 342                 snd_usb_endpoint_free(ep);
 343
 344         mutex_destroy(&chip->mutex);
 345         if (!atomic_read(&chip->shutdown))
 346                 dev_set_drvdata(&chip->dev->dev, NULL);
 347 }
 348
 349 static void usb_audio_make_shortname(struct usb_device *dev,
 350                                      struct snd_usb_audio *chip,
 351                                      const struct snd_usb_audio_quirk *quirk)
 352 {
 353         struct snd_card *card = chip->card;
 354
 355         if (quirk && quirk->product_name && *quirk->product_name) {
 356                 strlcpy(card->shortname, quirk->product_name,
 357                         sizeof(card->shortname));
 358                 return;
 359         }
 360
 361         /* retrieve the device string as shortname */
 362         if (!dev->descriptor.iProduct ||
 363             usb_string(dev, dev->descriptor.iProduct,
 364                        card->shortname, sizeof(card->shortname)) <= 0) {
 365                 /* no name available from anywhere, so use ID */
 366                 sprintf(card->shortname, "USB Device %#04x:%#04x",
 367                         USB_ID_VENDOR(chip->usb_id),
 368                         USB_ID_PRODUCT(chip->usb_id));
 369         }
 370
 371         strim(card->shortname);
 372 }
 373
 374 static void usb_audio_make_longname(struct usb_device *dev,
 375                                     struct snd_usb_audio *chip,
 376                                     const struct snd_usb_audio_quirk *quirk)
 377 {
 378         struct snd_card *card = chip->card;
 379         int len;
 380
 381         /* shortcut - if any pre-defined string is given, use it */
 382         if (quirk && quirk->profile_name && *quirk->profile_name) {
 383                 strlcpy(card->longname, quirk->profile_name,
 384                         sizeof(card->longname));
 385                 return;
 386         }
 387
 388         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
 389                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
 390         } else {
 391                 /* retrieve the vendor and device strings as longname */
 392                 if (dev->descriptor.iManufacturer)
 393                         len = usb_string(dev, dev->descriptor.iManufacturer,
 394                                          card->longname, sizeof(card->longname));
 395                 else
 396                         len = 0;
 397                 /* we don't really care if there isn't any vendor string */
 398         }
 399         if (len > 0) {
 400                 strim(card->longname);
 401                 if (*card->longname)
 402                         strlcat(card->longname, " ", sizeof(card->longname));
 403         }
 404
 405         strlcat(card->longname, card->shortname, sizeof(card->longname));
 406
 407         len = strlcat(card->longname, " at ", sizeof(card->longname));
 408
 409         if (len < sizeof(card->longname))
 410                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
 411
 412         switch (snd_usb_get_speed(dev)) {
 413         case USB_SPEED_LOW:
 414                 strlcat(card->longname, ", low speed", sizeof(card->longname));
 415                 break;
 416         case USB_SPEED_FULL:
 417                 strlcat(card->longname, ", full speed", sizeof(card->longname));
 418                 break;
 419         case USB_SPEED_HIGH:
 420                 strlcat(card->longname, ", high speed", sizeof(card->longname));
 421                 break;
 422         case USB_SPEED_SUPER:
 423                 strlcat(card->longname, ", super speed", sizeof(card->longname));
 424                 break;
 425         case USB_SPEED_SUPER_PLUS:
 426                 strlcat(card->longname, ", super speed plus", sizeof(card->longname));
 427                 break;
 428         default:
 429                 break;
 430         }
 431 }
 432
 433 /*
 434  * create a chip instance and set its names.
 435  */
 436 static int snd_usb_audio_create(struct usb_interface *intf,
 437                                 struct usb_device *dev, int idx,
 438                                 const struct snd_usb_audio_quirk *quirk,
 439                                 unsigned int usb_id,
 440                                 struct snd_usb_audio **rchip)
 441 {
 442         struct snd_card *card;
 443         struct snd_usb_audio *chip;
 444         int err;
 445         char component[14];
 446
 447         *rchip = NULL;
 448
 449         switch (snd_usb_get_speed(dev)) {
 450         case USB_SPEED_LOW:
 451         case USB_SPEED_FULL:
 452         case USB_SPEED_HIGH:
 453         case USB_SPEED_WIRELESS:
 454         case USB_SPEED_SUPER:
 455         case USB_SPEED_SUPER_PLUS:
 456                 break;
 457         default:
 458                 dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
 459                 return -ENXIO;
 460         }
 461
 462         err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
 463                            sizeof(*chip), &card);
 464         if (err < 0) {
 465                 dev_err(&dev->dev, "cannot create card instance %d\n", idx);
 466                 return err;
 467         }
 468
 469         chip = card->private_data;
 470         mutex_init(&chip->mutex);
 471         init_waitqueue_head(&chip->shutdown_wait);
 472         chip->index = idx;
 473         chip->dev = dev;
 474         chip->card = card;
 475         chip->setup = device_setup[idx];
 476         chip->autoclock = autoclock;
 477         atomic_set(&chip->active, 1); /* avoid autopm during probing */
 478         atomic_set(&chip->usage_count, 0);
 479         atomic_set(&chip->shutdown, 0);
 480
 481         chip->usb_id = usb_id;
 482         INIT_LIST_HEAD(&chip->pcm_list);
 483         INIT_LIST_HEAD(&chip->ep_list);
 484         INIT_LIST_HEAD(&chip->midi_list);
 485         INIT_LIST_HEAD(&chip->mixer_list);
 486
 487         card->private_free = snd_usb_audio_free;
 488
 489         strcpy(card->driver, "USB-Audio");
 490         sprintf(component, "USB%04x:%04x",
 491                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
 492         snd_component_add(card, component);
 493
 494         usb_audio_make_shortname(dev, chip, quirk);
 495         usb_audio_make_longname(dev, chip, quirk);
 496
 497         snd_usb_audio_create_proc(chip);
 498
 499         *rchip = chip;
 500         return 0;
 501 }
 502
 503 /* look for a matching quirk alias id */
 504 static bool get_alias_id(struct usb_device *dev, unsigned int *id)
 505 {
 506         int i;
 507         unsigned int src, dst;
 508
 509         for (i = 0; i < ARRAY_SIZE(quirk_alias); i++) {
 510                 if (!quirk_alias[i] ||
 511                     sscanf(quirk_alias[i], "%x:%x", &src, &dst) != 2 ||
 512                     src != *id)
 513                         continue;
 514                 dev_info(&dev->dev,
 515                          "device (%04x:%04x): applying quirk alias %04x:%04x\n",
 516                          USB_ID_VENDOR(*id), USB_ID_PRODUCT(*id),
 517                          USB_ID_VENDOR(dst), USB_ID_PRODUCT(dst));
 518                 *id = dst;
 519                 return true;
 520         }
 521
 522         return false;
 523 }
 524
 525 static const struct usb_device_id usb_audio_ids[]; /* defined below */
 526
 527 /* look for the corresponding quirk */
 528 static const struct snd_usb_audio_quirk *
 529 get_alias_quirk(struct usb_device *dev, unsigned int id)
 530 {
 531         const struct usb_device_id *p;
 532
 533         for (p = usb_audio_ids; p->match_flags; p++) {
 534                 /* FIXME: this checks only vendor:product pair in the list */
 535                 if ((p->match_flags & USB_DEVICE_ID_MATCH_DEVICE) ==
 536                     USB_DEVICE_ID_MATCH_DEVICE &&
 537                     p->idVendor == USB_ID_VENDOR(id) &&
 538                     p->idProduct == USB_ID_PRODUCT(id))
 539                         return (const struct snd_usb_audio_quirk *)p->driver_info;
 540         }
 541
 542         return NULL;
 543 }
 544
 545 /*
 546  * probe the active usb device
 547  *
 548  * note that this can be called multiple times per a device, when it
 549  * includes multiple audio control interfaces.
 550  *
 551  * thus we check the usb device pointer and creates the card instance
 552  * only at the first time.  the successive calls of this function will
 553  * append the pcm interface to the corresponding card.
 554  */
 555 static int usb_audio_probe(struct usb_interface *intf,
 556                            const struct usb_device_id *usb_id)
 557 {
 558         struct usb_device *dev = interface_to_usbdev(intf);
 559         const struct snd_usb_audio_quirk *quirk =
 560                 (const struct snd_usb_audio_quirk *)usb_id->driver_info;
 561         struct snd_usb_audio *chip;
 562         int i, err;
 563         struct usb_host_interface *alts;
 564         int ifnum;
 565         u32 id;
 566
 567         alts = &intf->altsetting[0];
 568         ifnum = get_iface_desc(alts)->bInterfaceNumber;
 569         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 570                     le16_to_cpu(dev->descriptor.idProduct));
 571         if (get_alias_id(dev, &id))
 572                 quirk = get_alias_quirk(dev, id);
 573         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
 574                 return -ENXIO;
 575
 576         err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
 577         if (err < 0)
 578                 return err;
 579
 580         /*
 581          * found a config.  now register to ALSA
 582          */
 583
 584         /* check whether it's already registered */
 585         chip = NULL;
 586         mutex_lock(&register_mutex);
 587         for (i = 0; i < SNDRV_CARDS; i++) {
 588                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
 589                         if (atomic_read(&usb_chip[i]->shutdown)) {
 590                                 dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
 591                                 err = -EIO;
 592                                 goto __error;
 593                         }
 594                         chip = usb_chip[i];
 595                         atomic_inc(&chip->active); /* avoid autopm */
 596                         break;
 597                 }
 598         }
 599         if (! chip) {
 600                 err = snd_usb_apply_boot_quirk_once(dev, intf, quirk, id);
 601                 if (err < 0)
 602                         goto __error;
 603
 604                 /* it's a fresh one.
 605                  * now look for an empty slot and create a new card instance
 606                  */
 607                 for (i = 0; i < SNDRV_CARDS; i++)
 608                         if (!usb_chip[i] &&
 609                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
 610                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
 611                                 if (enable[i]) {
 612                                         err = snd_usb_audio_create(intf, dev, i, quirk,
 613                                                                    id, &chip);
 614                                         if (err < 0)
 615                                                 goto __error;
 616                                         chip->pm_intf = intf;
 617                                         break;
 618                                 } else if (vid[i] != -1 || pid[i] != -1) {
 619                                         dev_info(&dev->dev,
 620                                                  "device (%04x:%04x) is disabled\n",
 621                                                  USB_ID_VENDOR(id),
 622                                                  USB_ID_PRODUCT(id));
 623                                         err = -ENOENT;
 624                                         goto __error;
 625                                 }
 626                         }
 627                 if (!chip) {
 628                         dev_err(&dev->dev, "no available usb audio device\n");
 629                         err = -ENODEV;
 630                         goto __error;
 631                 }
 632         }
 633         dev_set_drvdata(&dev->dev, chip);
 634
 635         /*
 636          * For devices with more than one control interface, we assume the
 637          * first contains the audio controls. We might need a more specific
 638          * check here in the future.
 639          */
 640         if (!chip->ctrl_intf)
 641                 chip->ctrl_intf = alts;
 642
 643         chip->txfr_quirk = 0;
 644         err = 1; /* continue */
 645         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
 646                 /* need some special handlings */
 647                 err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk);
 648                 if (err < 0)
 649                         goto __error;
 650         }
 651
 652         if (err > 0) {
 653                 /* create normal USB audio interfaces */
 654                 err = snd_usb_create_streams(chip, ifnum);
 655                 if (err < 0)
 656                         goto __error;
 657                 err = snd_usb_create_mixer(chip, ifnum, ignore_ctl_error);
 658                 if (err < 0)
 659                         goto __error;
 660         }
 661
 662         /* we are allowed to call snd_card_register() many times, but first
 663          * check to see if a device needs to skip it or do anything special
 664          */
 665         if (!snd_usb_registration_quirk(chip, ifnum)) {
 666                 err = snd_card_register(chip->card);
 667                 if (err < 0)
 668                         goto __error;
 669         }
 670
 671         if (quirk && quirk->shares_media_device) {
 672                 /* don't want to fail when snd_media_device_create() fails */
 673                 snd_media_device_create(chip, intf);
 674         }
 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                 /* chip->active is inside the chip->card object,
 686                  * decrement before memory is possibly returned.
 687                  */
 688                 atomic_dec(&chip->active);
 689                 if (!chip->num_interfaces)
 690                         snd_card_free(chip->card);
 691         }
 692         mutex_unlock(&register_mutex);
 693         return err;
 694 }
 695
 696 /*
 697  * we need to take care of counter, since disconnection can be called also
 698  * many times as well as usb_audio_probe().
 699  */
 700 static void usb_audio_disconnect(struct usb_interface *intf)
 701 {
 702         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 703         struct snd_card *card;
 704         struct list_head *p;
 705
 706         if (chip == USB_AUDIO_IFACE_UNUSED)
 707                 return;
 708
 709         card = chip->card;
 710
 711         mutex_lock(&register_mutex);
 712         if (atomic_inc_return(&chip->shutdown) == 1) {
 713                 struct snd_usb_stream *as;
 714                 struct snd_usb_endpoint *ep;
 715                 struct usb_mixer_interface *mixer;
 716
 717                 /* wait until all pending tasks done;
 718                  * they are protected by snd_usb_lock_shutdown()
 719                  */
 720                 wait_event(chip->shutdown_wait,
 721                            !atomic_read(&chip->usage_count));
 722                 snd_card_disconnect(card);
 723                 /* release the pcm resources */
 724                 list_for_each_entry(as, &chip->pcm_list, list) {
 725                         snd_usb_stream_disconnect(as);
 726                 }
 727                 /* release the endpoint resources */
 728                 list_for_each_entry(ep, &chip->ep_list, list) {
 729                         snd_usb_endpoint_release(ep);
 730                 }
 731                 /* release the midi resources */
 732                 list_for_each(p, &chip->midi_list) {
 733                         snd_usbmidi_disconnect(p);
 734                 }
 735                 /*
 736                  * Nice to check quirk && quirk->shares_media_device and
 737                  * then call the snd_media_device_delete(). Don't have
 738                  * access to the quirk here. snd_media_device_delete()
 739                  * accesses mixer_list
 740                  */
 741                 snd_media_device_delete(chip);
 742
 743                 /* release mixer resources */
 744                 list_for_each_entry(mixer, &chip->mixer_list, list) {
 745                         snd_usb_mixer_disconnect(mixer);
 746                 }
 747         }
 748
 749         chip->num_interfaces--;
 750         if (chip->num_interfaces <= 0) {
 751                 usb_chip[chip->index] = NULL;
 752                 mutex_unlock(&register_mutex);
 753                 snd_card_free_when_closed(card);
 754         } else {
 755                 mutex_unlock(&register_mutex);
 756         }
 757 }
 758
 759 /* lock the shutdown (disconnect) task and autoresume */
 760 int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
 761 {
 762         int err;
 763
 764         atomic_inc(&chip->usage_count);
 765         if (atomic_read(&chip->shutdown)) {
 766                 err = -EIO;
 767                 goto error;
 768         }
 769         err = snd_usb_autoresume(chip);
 770         if (err < 0)
 771                 goto error;
 772         return 0;
 773
 774  error:
 775         if (atomic_dec_and_test(&chip->usage_count))
 776                 wake_up(&chip->shutdown_wait);
 777         return err;
 778 }
 779
 780 /* autosuspend and unlock the shutdown */
 781 void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
 782 {
 783         snd_usb_autosuspend(chip);
 784         if (atomic_dec_and_test(&chip->usage_count))
 785                 wake_up(&chip->shutdown_wait);
 786 }
 787
 788 #ifdef CONFIG_PM
 789
 790 int snd_usb_autoresume(struct snd_usb_audio *chip)
 791 {
 792         if (atomic_read(&chip->shutdown))
 793                 return -EIO;
 794         if (atomic_inc_return(&chip->active) == 1)
 795                 return usb_autopm_get_interface(chip->pm_intf);
 796         return 0;
 797 }
 798
 799 void snd_usb_autosuspend(struct snd_usb_audio *chip)
 800 {
 801         if (atomic_read(&chip->shutdown))
 802                 return;
 803         if (atomic_dec_and_test(&chip->active))
 804                 usb_autopm_put_interface(chip->pm_intf);
 805 }
 806
 807 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 808 {
 809         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 810         struct snd_usb_stream *as;
 811         struct usb_mixer_interface *mixer;
 812         struct list_head *p;
 813
 814         if (chip == USB_AUDIO_IFACE_UNUSED)
 815                 return 0;
 816
 817         if (!chip->num_suspended_intf++) {
 818                 list_for_each_entry(as, &chip->pcm_list, list) {
 819                         snd_usb_pcm_suspend(as);
 820                         as->substream[0].need_setup_ep =
 821                                 as->substream[1].need_setup_ep = true;
 822                 }
 823                 list_for_each(p, &chip->midi_list)
 824                         snd_usbmidi_suspend(p);
 825                 list_for_each_entry(mixer, &chip->mixer_list, list)
 826                         snd_usb_mixer_suspend(mixer);
 827         }
 828
 829         if (!PMSG_IS_AUTO(message) && !chip->system_suspend) {
 830                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
 831                 chip->system_suspend = chip->num_suspended_intf;
 832         }
 833
 834         return 0;
 835 }
 836
 837 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
 838 {
 839         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 840         struct snd_usb_stream *as;
 841         struct usb_mixer_interface *mixer;
 842         struct list_head *p;
 843         int err = 0;
 844
 845         if (chip == USB_AUDIO_IFACE_UNUSED)
 846                 return 0;
 847
 848         atomic_inc(&chip->active); /* avoid autopm */
 849         if (chip->num_suspended_intf > 1)
 850                 goto out;
 851
 852         list_for_each_entry(as, &chip->pcm_list, list) {
 853                 err = snd_usb_pcm_resume(as);
 854                 if (err < 0)
 855                         goto err_out;
 856         }
 857
 858         /*
 859          * ALSA leaves material resumption to user space
 860          * we just notify and restart the mixers
 861          */
 862         list_for_each_entry(mixer, &chip->mixer_list, list) {
 863                 err = snd_usb_mixer_resume(mixer, reset_resume);
 864                 if (err < 0)
 865                         goto err_out;
 866         }
 867
 868         list_for_each(p, &chip->midi_list) {
 869                 snd_usbmidi_resume(p);
 870         }
 871
 872  out:
 873         if (chip->num_suspended_intf == chip->system_suspend) {
 874                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
 875                 chip->system_suspend = 0;
 876         }
 877         chip->num_suspended_intf--;
 878
 879 err_out:
 880         atomic_dec(&chip->active); /* allow autopm after this point */
 881         return err;
 882 }
 883
 884 static int usb_audio_resume(struct usb_interface *intf)
 885 {
 886         return __usb_audio_resume(intf, false);
 887 }
 888
 889 static int usb_audio_reset_resume(struct usb_interface *intf)
 890 {
 891         return __usb_audio_resume(intf, true);
 892 }
 893 #else
 894 #define usb_audio_suspend       NULL
 895 #define usb_audio_resume        NULL
 896 #define usb_audio_reset_resume  NULL
 897 #endif          /* CONFIG_PM */
 898
 899 static const struct usb_device_id usb_audio_ids [] = {
 900 #include "quirks-table.h"
 901     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
 902       .bInterfaceClass = USB_CLASS_AUDIO,
 903       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
 904     { }                                         /* Terminating entry */
 905 };
 906 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
 907
 908 /*
 909  * entry point for linux usb interface
 910  */
 911
 912 static struct usb_driver usb_audio_driver = {
 913         .name =         "snd-usb-audio",
 914         .probe =        usb_audio_probe,
 915         .disconnect =   usb_audio_disconnect,
 916         .suspend =      usb_audio_suspend,
 917         .resume =       usb_audio_resume,
 918         .reset_resume = usb_audio_reset_resume,
 919         .id_table =     usb_audio_ids,
 920         .supports_autosuspend = 1,
 921 };
 922
 923 module_usb_driver(usb_audio_driver);