card.c

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