sound/usb/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 nrpacks = 8;         /* max. number of packets per urb */
  83 static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
  84 static bool ignore_ctl_error;
  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(nrpacks, int, 0644);
  97 MODULE_PARM_DESC(nrpacks, "Max. number of packets per URB.");
  98 module_param_array(device_setup, int, NULL, 0444);
  99 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
 100 module_param(ignore_ctl_error, bool, 0444);
 101 MODULE_PARM_DESC(ignore_ctl_error,
 102                  "Ignore errors from USB controller for mixer interfaces.");
 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 snd_usb_audio_disconnect()
 116  */
 117 static void snd_usb_stream_disconnect(struct list_head *head)
 118 {
 119         int idx;
 120         struct snd_usb_stream *as;
 121         struct snd_usb_substream *subs;
 122
 123         as = list_entry(head, struct snd_usb_stream, list);
 124         for (idx = 0; idx < 2; idx++) {
 125                 subs = &as->substream[idx];
 126                 if (!subs->num_formats)
 127                         continue;
 128                 subs->interface = -1;
 129                 subs->data_endpoint = NULL;
 130                 subs->sync_endpoint = NULL;
 131         }
 132 }
 133
 134 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
 135 {
 136         struct usb_device *dev = chip->dev;
 137         struct usb_host_interface *alts;
 138         struct usb_interface_descriptor *altsd;
 139         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
 140
 141         if (!iface) {
 142                 snd_printk(KERN_ERR "%d:%u:%d : does not exist\n",
 143                            dev->devnum, ctrlif, interface);
 144                 return -EINVAL;
 145         }
 146
 147         if (usb_interface_claimed(iface)) {
 148                 snd_printdd(KERN_INFO "%d:%d:%d: skipping, already claimed\n",
 149                                                 dev->devnum, ctrlif, interface);
 150                 return -EINVAL;
 151         }
 152
 153         alts = &iface->altsetting[0];
 154         altsd = get_iface_desc(alts);
 155         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 156              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 157             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
 158                 int err = snd_usbmidi_create(chip->card, iface,
 159                                              &chip->midi_list, NULL);
 160                 if (err < 0) {
 161                         snd_printk(KERN_ERR "%d:%u:%d: cannot create sequencer device\n",
 162                                                 dev->devnum, ctrlif, interface);
 163                         return -EINVAL;
 164                 }
 165                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 166
 167                 return 0;
 168         }
 169
 170         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
 171              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 172             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
 173                 snd_printdd(KERN_ERR "%d:%u:%d: skipping non-supported interface %d\n",
 174                                         dev->devnum, ctrlif, interface, altsd->bInterfaceClass);
 175                 /* skip non-supported classes */
 176                 return -EINVAL;
 177         }
 178
 179         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
 180                 snd_printk(KERN_ERR "low speed audio streaming not supported\n");
 181                 return -EINVAL;
 182         }
 183
 184         if (! snd_usb_parse_audio_interface(chip, interface)) {
 185                 usb_set_interface(dev, interface, 0); /* reset the current interface */
 186                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 187                 return -EINVAL;
 188         }
 189
 190         return 0;
 191 }
 192
 193 /*
 194  * parse audio control descriptor and create pcm/midi streams
 195  */
 196 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 197 {
 198         struct usb_device *dev = chip->dev;
 199         struct usb_host_interface *host_iface;
 200         struct usb_interface_descriptor *altsd;
 201         void *control_header;
 202         int i, protocol;
 203
 204         /* find audiocontrol interface */
 205         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
 206         control_header = snd_usb_find_csint_desc(host_iface->extra,
 207                                                  host_iface->extralen,
 208                                                  NULL, UAC_HEADER);
 209         altsd = get_iface_desc(host_iface);
 210         protocol = altsd->bInterfaceProtocol;
 211
 212         if (!control_header) {
 213                 snd_printk(KERN_ERR "cannot find UAC_HEADER\n");
 214                 return -EINVAL;
 215         }
 216
 217         switch (protocol) {
 218         default:
 219                 snd_printdd(KERN_WARNING "unknown interface protocol %#02x, assuming v1\n",
 220                             protocol);
 221                 /* fall through */
 222
 223         case UAC_VERSION_1: {
 224                 struct uac1_ac_header_descriptor *h1 = control_header;
 225
 226                 if (!h1->bInCollection) {
 227                         snd_printk(KERN_INFO "skipping empty audio interface (v1)\n");
 228                         return -EINVAL;
 229                 }
 230
 231                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
 232                         snd_printk(KERN_ERR "invalid UAC_HEADER (v1)\n");
 233                         return -EINVAL;
 234                 }
 235
 236                 for (i = 0; i < h1->bInCollection; i++)
 237                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
 238
 239                 break;
 240         }
 241
 242         case UAC_VERSION_2: {
 243                 struct usb_interface_assoc_descriptor *assoc =
 244                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
 245
 246                 if (!assoc) {
 247                         /*
 248                          * Firmware writers cannot count to three.  So to find
 249                          * the IAD on the NuForce UDH-100, also check the next
 250                          * interface.
 251                          */
 252                         struct usb_interface *iface =
 253                                 usb_ifnum_to_if(dev, ctrlif + 1);
 254                         if (iface &&
 255                             iface->intf_assoc &&
 256                             iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
 257                             iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
 258                                 assoc = iface->intf_assoc;
 259                 }
 260
 261                 if (!assoc) {
 262                         snd_printk(KERN_ERR "Audio class v2 interfaces need an interface association\n");
 263                         return -EINVAL;
 264                 }
 265
 266                 for (i = 0; i < assoc->bInterfaceCount; i++) {
 267                         int intf = assoc->bFirstInterface + i;
 268
 269                         if (intf != ctrlif)
 270                                 snd_usb_create_stream(chip, ctrlif, intf);
 271                 }
 272
 273                 break;
 274         }
 275         }
 276
 277         return 0;
 278 }
 279
 280 /*
 281  * free the chip instance
 282  *
 283  * here we have to do not much, since pcm and controls are already freed
 284  *
 285  */
 286
 287 static int snd_usb_audio_free(struct snd_usb_audio *chip)
 288 {
 289         mutex_destroy(&chip->mutex);
 290         kfree(chip);
 291         return 0;
 292 }
 293
 294 static int snd_usb_audio_dev_free(struct snd_device *device)
 295 {
 296         struct snd_usb_audio *chip = device->device_data;
 297         return snd_usb_audio_free(chip);
 298 }
 299
 300 static void remove_trailing_spaces(char *str)
 301 {
 302         char *p;
 303
 304         if (!*str)
 305                 return;
 306         for (p = str + strlen(str) - 1; p >= str && isspace(*p); p--)
 307                 *p = 0;
 308 }
 309
 310 /*
 311  * create a chip instance and set its names.
 312  */
 313 static int snd_usb_audio_create(struct usb_device *dev, int idx,
 314                                 const struct snd_usb_audio_quirk *quirk,
 315                                 struct snd_usb_audio **rchip)
 316 {
 317         struct snd_card *card;
 318         struct snd_usb_audio *chip;
 319         int err, len;
 320         char component[14];
 321         static struct snd_device_ops ops = {
 322                 .dev_free =     snd_usb_audio_dev_free,
 323         };
 324
 325         *rchip = NULL;
 326
 327         switch (snd_usb_get_speed(dev)) {
 328         case USB_SPEED_LOW:
 329         case USB_SPEED_FULL:
 330         case USB_SPEED_HIGH:
 331         case USB_SPEED_SUPER:
 332                 break;
 333         default:
 334                 snd_printk(KERN_ERR "unknown device speed %d\n", snd_usb_get_speed(dev));
 335                 return -ENXIO;
 336         }
 337
 338         err = snd_card_create(index[idx], id[idx], THIS_MODULE, 0, &card);
 339         if (err < 0) {
 340                 snd_printk(KERN_ERR "cannot create card instance %d\n", idx);
 341                 return err;
 342         }
 343
 344         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 345         if (! chip) {
 346                 snd_card_free(card);
 347                 return -ENOMEM;
 348         }
 349
 350         mutex_init(&chip->mutex);
 351         init_rwsem(&chip->shutdown_rwsem);
 352         chip->index = idx;
 353         chip->dev = dev;
 354         chip->card = card;
 355         chip->setup = device_setup[idx];
 356         chip->nrpacks = nrpacks;
 357         chip->probing = 1;
 358
 359         chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 360                               le16_to_cpu(dev->descriptor.idProduct));
 361         INIT_LIST_HEAD(&chip->pcm_list);
 362         INIT_LIST_HEAD(&chip->ep_list);
 363         INIT_LIST_HEAD(&chip->midi_list);
 364         INIT_LIST_HEAD(&chip->mixer_list);
 365
 366         if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
 367                 snd_usb_audio_free(chip);
 368                 snd_card_free(card);
 369                 return err;
 370         }
 371
 372         strcpy(card->driver, "USB-Audio");
 373         sprintf(component, "USB%04x:%04x",
 374                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
 375         snd_component_add(card, component);
 376
 377         /* retrieve the device string as shortname */
 378         if (quirk && quirk->product_name && *quirk->product_name) {
 379                 strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
 380         } else {
 381                 if (!dev->descriptor.iProduct ||
 382                     usb_string(dev, dev->descriptor.iProduct,
 383                     card->shortname, sizeof(card->shortname)) <= 0) {
 384                         /* no name available from anywhere, so use ID */
 385                         sprintf(card->shortname, "USB Device %#04x:%#04x",
 386                                 USB_ID_VENDOR(chip->usb_id),
 387                                 USB_ID_PRODUCT(chip->usb_id));
 388                 }
 389         }
 390         remove_trailing_spaces(card->shortname);
 391
 392         /* retrieve the vendor and device strings as longname */
 393         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
 394                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
 395         } else {
 396                 if (dev->descriptor.iManufacturer)
 397                         len = usb_string(dev, dev->descriptor.iManufacturer,
 398                                          card->longname, sizeof(card->longname));
 399                 else
 400                         len = 0;
 401                 /* we don't really care if there isn't any vendor string */
 402         }
 403         if (len > 0) {
 404                 remove_trailing_spaces(card->longname);
 405                 if (*card->longname)
 406                         strlcat(card->longname, " ", sizeof(card->longname));
 407         }
 408
 409         strlcat(card->longname, card->shortname, sizeof(card->longname));
 410
 411         len = strlcat(card->longname, " at ", sizeof(card->longname));
 412
 413         if (len < sizeof(card->longname))
 414                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
 415
 416         switch (snd_usb_get_speed(dev)) {
 417         case USB_SPEED_LOW:
 418                 strlcat(card->longname, ", low speed", sizeof(card->longname));
 419                 break;
 420         case USB_SPEED_FULL:
 421                 strlcat(card->longname, ", full speed", sizeof(card->longname));
 422                 break;
 423         case USB_SPEED_HIGH:
 424                 strlcat(card->longname, ", high speed", sizeof(card->longname));
 425                 break;
 426         case USB_SPEED_SUPER:
 427                 strlcat(card->longname, ", super speed", sizeof(card->longname));
 428                 break;
 429         default:
 430                 break;
 431         }
 432
 433         snd_usb_audio_create_proc(chip);
 434
 435         *rchip = chip;
 436         return 0;
 437 }
 438
 439 /*
 440  * probe the active usb device
 441  *
 442  * note that this can be called multiple times per a device, when it
 443  * includes multiple audio control interfaces.
 444  *
 445  * thus we check the usb device pointer and creates the card instance
 446  * only at the first time.  the successive calls of this function will
 447  * append the pcm interface to the corresponding card.
 448  */
 449 static struct snd_usb_audio *
 450 snd_usb_audio_probe(struct usb_device *dev,
 451                     struct usb_interface *intf,
 452                     const struct usb_device_id *usb_id)
 453 {
 454         const struct snd_usb_audio_quirk *quirk = (const struct snd_usb_audio_quirk *)usb_id->driver_info;
 455         int i, err;
 456         struct snd_usb_audio *chip;
 457         struct usb_host_interface *alts;
 458         int ifnum;
 459         u32 id;
 460
 461         alts = &intf->altsetting[0];
 462         ifnum = get_iface_desc(alts)->bInterfaceNumber;
 463         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 464                     le16_to_cpu(dev->descriptor.idProduct));
 465         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
 466                 goto __err_val;
 467
 468         if (snd_usb_apply_boot_quirk(dev, intf, quirk) < 0)
 469                 goto __err_val;
 470
 471         /*
 472          * found a config.  now register to ALSA
 473          */
 474
 475         /* check whether it's already registered */
 476         chip = NULL;
 477         mutex_lock(&register_mutex);
 478         for (i = 0; i < SNDRV_CARDS; i++) {
 479                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
 480                         if (usb_chip[i]->shutdown) {
 481                                 snd_printk(KERN_ERR "USB device is in the shutdown state, cannot create a card instance\n");
 482                                 goto __error;
 483                         }
 484                         chip = usb_chip[i];
 485                         chip->probing = 1;
 486                         break;
 487                 }
 488         }
 489         if (! chip) {
 490                 /* it's a fresh one.
 491                  * now look for an empty slot and create a new card instance
 492                  */
 493                 for (i = 0; i < SNDRV_CARDS; i++)
 494                         if (enable[i] && ! usb_chip[i] &&
 495                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
 496                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
 497                                 if (snd_usb_audio_create(dev, i, quirk, &chip) < 0) {
 498                                         goto __error;
 499                                 }
 500                                 snd_card_set_dev(chip->card, &intf->dev);
 501                                 chip->pm_intf = intf;
 502                                 break;
 503                         }
 504                 if (!chip) {
 505                         printk(KERN_ERR "no available usb audio device\n");
 506                         goto __error;
 507                 }
 508         }
 509
 510         /*
 511          * For devices with more than one control interface, we assume the
 512          * first contains the audio controls. We might need a more specific
 513          * check here in the future.
 514          */
 515         if (!chip->ctrl_intf)
 516                 chip->ctrl_intf = alts;
 517
 518         chip->txfr_quirk = 0;
 519         err = 1; /* continue */
 520         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
 521                 /* need some special handlings */
 522                 if ((err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk)) < 0)
 523                         goto __error;
 524         }
 525
 526         if (err > 0) {
 527                 /* create normal USB audio interfaces */
 528                 if (snd_usb_create_streams(chip, ifnum) < 0 ||
 529                     snd_usb_create_mixer(chip, ifnum, ignore_ctl_error) < 0) {
 530                         goto __error;
 531                 }
 532         }
 533
 534         /* we are allowed to call snd_card_register() many times */
 535         if (snd_card_register(chip->card) < 0) {
 536                 goto __error;
 537         }
 538
 539         usb_chip[chip->index] = chip;
 540         chip->num_interfaces++;
 541         chip->probing = 0;
 542         mutex_unlock(&register_mutex);
 543         return chip;
 544
 545  __error:
 546         if (chip) {
 547                 if (!chip->num_interfaces)
 548                         snd_card_free(chip->card);
 549                 chip->probing = 0;
 550         }
 551         mutex_unlock(&register_mutex);
 552  __err_val:
 553         return NULL;
 554 }
 555
 556 /*
 557  * we need to take care of counter, since disconnection can be called also
 558  * many times as well as usb_audio_probe().
 559  */
 560 static void snd_usb_audio_disconnect(struct usb_device *dev,
 561                                      struct snd_usb_audio *chip)
 562 {
 563         struct snd_card *card;
 564         struct list_head *p, *n;
 565
 566         if (chip == (void *)-1L)
 567                 return;
 568
 569         card = chip->card;
 570         down_write(&chip->shutdown_rwsem);
 571         chip->shutdown = 1;
 572         up_write(&chip->shutdown_rwsem);
 573
 574         mutex_lock(&register_mutex);
 575         chip->num_interfaces--;
 576         if (chip->num_interfaces <= 0) {
 577                 snd_card_disconnect(card);
 578                 /* release the pcm resources */
 579                 list_for_each(p, &chip->pcm_list) {
 580                         snd_usb_stream_disconnect(p);
 581                 }
 582                 /* release the endpoint resources */
 583                 list_for_each_safe(p, n, &chip->ep_list) {
 584                         snd_usb_endpoint_free(p);
 585                 }
 586                 /* release the midi resources */
 587                 list_for_each(p, &chip->midi_list) {
 588                         snd_usbmidi_disconnect(p);
 589                 }
 590                 /* release mixer resources */
 591                 list_for_each(p, &chip->mixer_list) {
 592                         snd_usb_mixer_disconnect(p);
 593                 }
 594                 usb_chip[chip->index] = NULL;
 595                 mutex_unlock(&register_mutex);
 596                 snd_card_free_when_closed(card);
 597         } else {
 598                 mutex_unlock(&register_mutex);
 599         }
 600 }
 601
 602 /*
 603  * new 2.5 USB kernel API
 604  */
 605 static int usb_audio_probe(struct usb_interface *intf,
 606                            const struct usb_device_id *id)
 607 {
 608         struct snd_usb_audio *chip;
 609         chip = snd_usb_audio_probe(interface_to_usbdev(intf), intf, id);
 610         if (chip) {
 611                 usb_set_intfdata(intf, chip);
 612                 return 0;
 613         } else
 614                 return -EIO;
 615 }
 616
 617 static void usb_audio_disconnect(struct usb_interface *intf)
 618 {
 619         snd_usb_audio_disconnect(interface_to_usbdev(intf),
 620                                  usb_get_intfdata(intf));
 621 }
 622
 623 #ifdef CONFIG_PM
 624
 625 int snd_usb_autoresume(struct snd_usb_audio *chip)
 626 {
 627         int err = -ENODEV;
 628
 629         down_read(&chip->shutdown_rwsem);
 630         if (!chip->shutdown && !chip->probing)
 631                 err = usb_autopm_get_interface(chip->pm_intf);
 632         up_read(&chip->shutdown_rwsem);
 633
 634         return err;
 635 }
 636
 637 void snd_usb_autosuspend(struct snd_usb_audio *chip)
 638 {
 639         down_read(&chip->shutdown_rwsem);
 640         if (!chip->shutdown && !chip->probing)
 641                 usb_autopm_put_interface(chip->pm_intf);
 642         up_read(&chip->shutdown_rwsem);
 643 }
 644
 645 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 646 {
 647         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 648         struct list_head *p;
 649         struct snd_usb_stream *as;
 650         struct usb_mixer_interface *mixer;
 651
 652         if (chip == (void *)-1L)
 653                 return 0;
 654
 655         if (!PMSG_IS_AUTO(message)) {
 656                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
 657                 if (!chip->num_suspended_intf++) {
 658                         list_for_each(p, &chip->pcm_list) {
 659                                 as = list_entry(p, struct snd_usb_stream, list);
 660                                 snd_pcm_suspend_all(as->pcm);
 661                                 as->substream[0].need_setup_ep =
 662                                         as->substream[1].need_setup_ep = true;
 663                         }
 664                 }
 665         } else {
 666                 /*
 667                  * otherwise we keep the rest of the system in the dark
 668                  * to keep this transparent
 669                  */
 670                 if (!chip->num_suspended_intf++)
 671                         chip->autosuspended = 1;
 672         }
 673
 674         list_for_each_entry(mixer, &chip->mixer_list, list)
 675                 snd_usb_mixer_inactivate(mixer);
 676
 677         return 0;
 678 }
 679
 680 static int usb_audio_resume(struct usb_interface *intf)
 681 {
 682         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 683         struct usb_mixer_interface *mixer;
 684         int err = 0;
 685
 686         if (chip == (void *)-1L)
 687                 return 0;
 688         if (--chip->num_suspended_intf)
 689                 return 0;
 690         /*
 691          * ALSA leaves material resumption to user space
 692          * we just notify and restart the mixers
 693          */
 694         list_for_each_entry(mixer, &chip->mixer_list, list) {
 695                 err = snd_usb_mixer_activate(mixer);
 696                 if (err < 0)
 697                         goto err_out;
 698         }
 699
 700         if (!chip->autosuspended)
 701                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
 702         chip->autosuspended = 0;
 703
 704 err_out:
 705         return err;
 706 }
 707 #else
 708 #define usb_audio_suspend       NULL
 709 #define usb_audio_resume        NULL
 710 #endif          /* CONFIG_PM */
 711
 712 static struct usb_device_id usb_audio_ids [] = {
 713 #include "quirks-table.h"
 714     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
 715       .bInterfaceClass = USB_CLASS_AUDIO,
 716       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
 717     { }                                         /* Terminating entry */
 718 };
 719
 720 MODULE_DEVICE_TABLE (usb, usb_audio_ids);
 721
 722 /*
 723  * entry point for linux usb interface
 724  */
 725
 726 static struct usb_driver usb_audio_driver = {
 727         .name =         "snd-usb-audio",
 728         .probe =        usb_audio_probe,
 729         .disconnect =   usb_audio_disconnect,
 730         .suspend =      usb_audio_suspend,
 731         .resume =       usb_audio_resume,
 732         .id_table =     usb_audio_ids,
 733         .supports_autosuspend = 1,
 734 };
 735
 736 static int __init snd_usb_audio_init(void)
 737 {
 738         if (nrpacks < 1 || nrpacks > MAX_PACKS) {
 739                 printk(KERN_WARNING "invalid nrpacks value.\n");
 740                 return -EINVAL;
 741         }
 742         return usb_register(&usb_audio_driver);
 743 }
 744
 745 static void __exit snd_usb_audio_cleanup(void)
 746 {
 747         usb_deregister(&usb_audio_driver);
 748 }
 749
 750 module_init(snd_usb_audio_init);
 751 module_exit(snd_usb_audio_cleanup);