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  *   - async unlink should be used for avoiding the sleep inside lock.
  29  *     2.4.22 usb-uhci seems buggy for async unlinking and results in
  30  *     oops.  in such a cse, pass async_unlink=0 option.
  31  *   - the linked URBs would be preferred but not used so far because of
  32  *     the instability of unlinking.
  33  *   - type II is not supported properly.  there is no device which supports
  34  *     this type *correctly*.  SB extigy looks as if it supports, but it's
  35  *     indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
  36  */
  37
  38
  39 #include <linux/bitops.h>
  40 #include <linux/init.h>
  41 #include <linux/list.h>
  42 #include <linux/slab.h>
  43 #include <linux/string.h>
  44 #include <linux/ctype.h>
  45 #include <linux/usb.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/mutex.h>
  48 #include <linux/usb/audio.h>
  49 #include <linux/usb/audio-v2.h>
  50 #include <linux/module.h>
  51
  52 #include <sound/control.h>
  53 #include <sound/core.h>
  54 #include <sound/info.h>
  55 #include <sound/pcm.h>
  56 #include <sound/pcm_params.h>
  57 #include <sound/initval.h>
  58
  59 #include "usbaudio.h"
  60 #include "card.h"
  61 #include "midi.h"
  62 #include "mixer.h"
  63 #include "proc.h"
  64 #include "quirks.h"
  65 #include "endpoint.h"
  66 #include "helper.h"
  67 #include "debug.h"
  68 #include "pcm.h"
  69 #include "format.h"
  70 #include "power.h"
  71 #include "stream.h"
  72
  73 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
  74 MODULE_DESCRIPTION("USB Audio");
  75 MODULE_LICENSE("GPL");
  76 MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
  77
  78
  79 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  80 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  81 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
  82 /* Vendor/product IDs for this card */
  83 static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  84 static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
  85 static int nrpacks = 8;         /* max. number of packets per urb */
  86 static bool async_unlink = 1;
  87 static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
  88 static bool ignore_ctl_error;
  89
  90 module_param_array(index, int, NULL, 0444);
  91 MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
  92 module_param_array(id, charp, NULL, 0444);
  93 MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
  94 module_param_array(enable, bool, NULL, 0444);
  95 MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
  96 module_param_array(vid, int, NULL, 0444);
  97 MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
  98 module_param_array(pid, int, NULL, 0444);
  99 MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
 100 module_param(nrpacks, int, 0644);
 101 MODULE_PARM_DESC(nrpacks, "Max. number of packets per URB.");
 102 module_param(async_unlink, bool, 0444);
 103 MODULE_PARM_DESC(async_unlink, "Use async unlink mode.");
 104 module_param_array(device_setup, int, NULL, 0444);
 105 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
 106 module_param(ignore_ctl_error, bool, 0444);
 107 MODULE_PARM_DESC(ignore_ctl_error,
 108                  "Ignore errors from USB controller for mixer interfaces.");
 109
 110 /*
 111  * we keep the snd_usb_audio_t instances by ourselves for merging
 112  * the all interfaces on the same card as one sound device.
 113  */
 114
 115 static DEFINE_MUTEX(register_mutex);
 116 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
 117 static struct usb_driver usb_audio_driver;
 118
 119 /*
 120  * disconnect streams
 121  * called from snd_usb_audio_disconnect()
 122  */
 123 static void snd_usb_stream_disconnect(struct list_head *head)
 124 {
 125         int idx;
 126         struct snd_usb_stream *as;
 127         struct snd_usb_substream *subs;
 128
 129         as = list_entry(head, struct snd_usb_stream, list);
 130         for (idx = 0; idx < 2; idx++) {
 131                 subs = &as->substream[idx];
 132                 if (!subs->num_formats)
 133                         continue;
 134                 snd_usb_release_substream_urbs(subs, 1);
 135                 subs->interface = -1;
 136         }
 137 }
 138
 139 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
 140 {
 141         struct usb_device *dev = chip->dev;
 142         struct usb_host_interface *alts;
 143         struct usb_interface_descriptor *altsd;
 144         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
 145
 146         if (!iface) {
 147                 snd_printk(KERN_ERR "%d:%u:%d : does not exist\n",
 148                            dev->devnum, ctrlif, interface);
 149                 return -EINVAL;
 150         }
 151
 152         if (usb_interface_claimed(iface)) {
 153                 snd_printdd(KERN_INFO "%d:%d:%d: skipping, already claimed\n",
 154                                                 dev->devnum, ctrlif, interface);
 155                 return -EINVAL;
 156         }
 157
 158         alts = &iface->altsetting[0];
 159         altsd = get_iface_desc(alts);
 160         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 161              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 162             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
 163                 int err = snd_usbmidi_create(chip->card, iface,
 164                                              &chip->midi_list, NULL);
 165                 if (err < 0) {
 166                         snd_printk(KERN_ERR "%d:%u:%d: cannot create sequencer device\n",
 167                                                 dev->devnum, ctrlif, interface);
 168                         return -EINVAL;
 169                 }
 170                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 171
 172                 return 0;
 173         }
 174
 175         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
 176              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 177             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
 178                 snd_printdd(KERN_ERR "%d:%u:%d: skipping non-supported interface %d\n",
 179                                         dev->devnum, ctrlif, interface, altsd->bInterfaceClass);
 180                 /* skip non-supported classes */
 181                 return -EINVAL;
 182         }
 183
 184         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
 185                 snd_printk(KERN_ERR "low speed audio streaming not supported\n");
 186                 return -EINVAL;
 187         }
 188
 189         if (! snd_usb_parse_audio_interface(chip, interface)) {
 190                 usb_set_interface(dev, interface, 0); /* reset the current interface */
 191                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 192                 return -EINVAL;
 193         }
 194
 195         return 0;
 196 }
 197
 198 /*
 199  * parse audio control descriptor and create pcm/midi streams
 200  */
 201 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 202 {
 203         struct usb_device *dev = chip->dev;
 204         struct usb_host_interface *host_iface;
 205         struct usb_interface_descriptor *altsd;
 206         void *control_header;
 207         int i, protocol;
 208
 209         /* find audiocontrol interface */
 210         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
 211         control_header = snd_usb_find_csint_desc(host_iface->extra,
 212                                                  host_iface->extralen,
 213                                                  NULL, UAC_HEADER);
 214         altsd = get_iface_desc(host_iface);
 215         protocol = altsd->bInterfaceProtocol;
 216
 217         if (!control_header) {
 218                 snd_printk(KERN_ERR "cannot find UAC_HEADER\n");
 219                 return -EINVAL;
 220         }
 221
 222         switch (protocol) {
 223         default:
 224                 snd_printdd(KERN_WARNING "unknown interface protocol %#02x, assuming v1\n",
 225                             protocol);
 226                 /* fall through */
 227
 228         case UAC_VERSION_1: {
 229                 struct uac1_ac_header_descriptor *h1 = control_header;
 230
 231                 if (!h1->bInCollection) {
 232                         snd_printk(KERN_INFO "skipping empty audio interface (v1)\n");
 233                         return -EINVAL;
 234                 }
 235
 236                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
 237                         snd_printk(KERN_ERR "invalid UAC_HEADER (v1)\n");
 238                         return -EINVAL;
 239                 }
 240
 241                 for (i = 0; i < h1->bInCollection; i++)
 242                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
 243
 244                 break;
 245         }
 246
 247         case UAC_VERSION_2: {
 248                 struct usb_interface_assoc_descriptor *assoc =
 249                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
 250
 251                 if (!assoc) {
 252                         snd_printk(KERN_ERR "Audio class v2 interfaces need an interface association\n");
 253                         return -EINVAL;
 254                 }
 255
 256                 for (i = 0; i < assoc->bInterfaceCount; i++) {
 257                         int intf = assoc->bFirstInterface + i;
 258
 259                         if (intf != ctrlif)
 260                                 snd_usb_create_stream(chip, ctrlif, intf);
 261                 }
 262
 263                 break;
 264         }
 265         }
 266
 267         return 0;
 268 }
 269
 270 /*
 271  * free the chip instance
 272  *
 273  * here we have to do not much, since pcm and controls are already freed
 274  *
 275  */
 276
 277 static int snd_usb_audio_free(struct snd_usb_audio *chip)
 278 {
 279         kfree(chip);
 280         return 0;
 281 }
 282
 283 static int snd_usb_audio_dev_free(struct snd_device *device)
 284 {
 285         struct snd_usb_audio *chip = device->device_data;
 286         return snd_usb_audio_free(chip);
 287 }
 288
 289 static void remove_trailing_spaces(char *str)
 290 {
 291         char *p;
 292
 293         if (!*str)
 294                 return;
 295         for (p = str + strlen(str) - 1; p >= str && isspace(*p); p--)
 296                 *p = 0;
 297 }
 298
 299 /*
 300  * create a chip instance and set its names.
 301  */
 302 static int snd_usb_audio_create(struct usb_device *dev, int idx,
 303                                 const struct snd_usb_audio_quirk *quirk,
 304                                 struct snd_usb_audio **rchip)
 305 {
 306         struct snd_card *card;
 307         struct snd_usb_audio *chip;
 308         int err, len;
 309         char component[14];
 310         static struct snd_device_ops ops = {
 311                 .dev_free =     snd_usb_audio_dev_free,
 312         };
 313
 314         *rchip = NULL;
 315
 316         switch (snd_usb_get_speed(dev)) {
 317         case USB_SPEED_LOW:
 318         case USB_SPEED_FULL:
 319         case USB_SPEED_HIGH:
 320         case USB_SPEED_SUPER:
 321                 break;
 322         default:
 323                 snd_printk(KERN_ERR "unknown device speed %d\n", snd_usb_get_speed(dev));
 324                 return -ENXIO;
 325         }
 326
 327         err = snd_card_create(index[idx], id[idx], THIS_MODULE, 0, &card);
 328         if (err < 0) {
 329                 snd_printk(KERN_ERR "cannot create card instance %d\n", idx);
 330                 return err;
 331         }
 332
 333         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 334         if (! chip) {
 335                 snd_card_free(card);
 336                 return -ENOMEM;
 337         }
 338
 339         mutex_init(&chip->shutdown_mutex);
 340         chip->index = idx;
 341         chip->dev = dev;
 342         chip->card = card;
 343         chip->setup = device_setup[idx];
 344         chip->nrpacks = nrpacks;
 345         chip->async_unlink = async_unlink;
 346         chip->probing = 1;
 347
 348         chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 349                               le16_to_cpu(dev->descriptor.idProduct));
 350         INIT_LIST_HEAD(&chip->pcm_list);
 351         INIT_LIST_HEAD(&chip->midi_list);
 352         INIT_LIST_HEAD(&chip->mixer_list);
 353
 354         if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
 355                 snd_usb_audio_free(chip);
 356                 snd_card_free(card);
 357                 return err;
 358         }
 359
 360         strcpy(card->driver, "USB-Audio");
 361         sprintf(component, "USB%04x:%04x",
 362                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
 363         snd_component_add(card, component);
 364
 365         /* retrieve the device string as shortname */
 366         if (quirk && quirk->product_name && *quirk->product_name) {
 367                 strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
 368         } else {
 369                 if (!dev->descriptor.iProduct ||
 370                     usb_string(dev, dev->descriptor.iProduct,
 371                     card->shortname, sizeof(card->shortname)) <= 0) {
 372                         /* no name available from anywhere, so use ID */
 373                         sprintf(card->shortname, "USB Device %#04x:%#04x",
 374                                 USB_ID_VENDOR(chip->usb_id),
 375                                 USB_ID_PRODUCT(chip->usb_id));
 376                 }
 377         }
 378         remove_trailing_spaces(card->shortname);
 379
 380         /* retrieve the vendor and device strings as longname */
 381         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
 382                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
 383         } else {
 384                 if (dev->descriptor.iManufacturer)
 385                         len = usb_string(dev, dev->descriptor.iManufacturer,
 386                                          card->longname, sizeof(card->longname));
 387                 else
 388                         len = 0;
 389                 /* we don't really care if there isn't any vendor string */
 390         }
 391         if (len > 0) {
 392                 remove_trailing_spaces(card->longname);
 393                 if (*card->longname)
 394                         strlcat(card->longname, " ", sizeof(card->longname));
 395         }
 396
 397         strlcat(card->longname, card->shortname, sizeof(card->longname));
 398
 399         len = strlcat(card->longname, " at ", sizeof(card->longname));
 400
 401         if (len < sizeof(card->longname))
 402                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
 403
 404         switch (snd_usb_get_speed(dev)) {
 405         case USB_SPEED_LOW:
 406                 strlcat(card->longname, ", low speed", sizeof(card->longname));
 407                 break;
 408         case USB_SPEED_FULL:
 409                 strlcat(card->longname, ", full speed", sizeof(card->longname));
 410                 break;
 411         case USB_SPEED_HIGH:
 412                 strlcat(card->longname, ", high speed", sizeof(card->longname));
 413                 break;
 414         case USB_SPEED_SUPER:
 415                 strlcat(card->longname, ", super speed", sizeof(card->longname));
 416                 break;
 417         default:
 418                 break;
 419         }
 420
 421         snd_usb_audio_create_proc(chip);
 422
 423         *rchip = chip;
 424         return 0;
 425 }
 426
 427 /*
 428  * probe the active usb device
 429  *
 430  * note that this can be called multiple times per a device, when it
 431  * includes multiple audio control interfaces.
 432  *
 433  * thus we check the usb device pointer and creates the card instance
 434  * only at the first time.  the successive calls of this function will
 435  * append the pcm interface to the corresponding card.
 436  */
 437 static struct snd_usb_audio *
 438 snd_usb_audio_probe(struct usb_device *dev,
 439                     struct usb_interface *intf,
 440                     const struct usb_device_id *usb_id)
 441 {
 442         const struct snd_usb_audio_quirk *quirk = (const struct snd_usb_audio_quirk *)usb_id->driver_info;
 443         int i, err;
 444         struct snd_usb_audio *chip;
 445         struct usb_host_interface *alts;
 446         int ifnum;
 447         u32 id;
 448
 449         alts = &intf->altsetting[0];
 450         ifnum = get_iface_desc(alts)->bInterfaceNumber;
 451         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 452                     le16_to_cpu(dev->descriptor.idProduct));
 453         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
 454                 goto __err_val;
 455
 456         if (snd_usb_apply_boot_quirk(dev, intf, quirk) < 0)
 457                 goto __err_val;
 458
 459         /*
 460          * found a config.  now register to ALSA
 461          */
 462
 463         /* check whether it's already registered */
 464         chip = NULL;
 465         mutex_lock(&register_mutex);
 466         for (i = 0; i < SNDRV_CARDS; i++) {
 467                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
 468                         if (usb_chip[i]->shutdown) {
 469                                 snd_printk(KERN_ERR "USB device is in the shutdown state, cannot create a card instance\n");
 470                                 goto __error;
 471                         }
 472                         chip = usb_chip[i];
 473                         chip->probing = 1;
 474                         break;
 475                 }
 476         }
 477         if (! chip) {
 478                 /* it's a fresh one.
 479                  * now look for an empty slot and create a new card instance
 480                  */
 481                 for (i = 0; i < SNDRV_CARDS; i++)
 482                         if (enable[i] && ! usb_chip[i] &&
 483                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
 484                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
 485                                 if (snd_usb_audio_create(dev, i, quirk, &chip) < 0) {
 486                                         goto __error;
 487                                 }
 488                                 snd_card_set_dev(chip->card, &intf->dev);
 489                                 chip->pm_intf = intf;
 490                                 break;
 491                         }
 492                 if (!chip) {
 493                         printk(KERN_ERR "no available usb audio device\n");
 494                         goto __error;
 495                 }
 496         }
 497
 498         /*
 499          * For devices with more than one control interface, we assume the
 500          * first contains the audio controls. We might need a more specific
 501          * check here in the future.
 502          */
 503         if (!chip->ctrl_intf)
 504                 chip->ctrl_intf = alts;
 505
 506         chip->txfr_quirk = 0;
 507         err = 1; /* continue */
 508         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
 509                 /* need some special handlings */
 510                 if ((err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk)) < 0)
 511                         goto __error;
 512         }
 513
 514         if (err > 0) {
 515                 /* create normal USB audio interfaces */
 516                 if (snd_usb_create_streams(chip, ifnum) < 0 ||
 517                     snd_usb_create_mixer(chip, ifnum, ignore_ctl_error) < 0) {
 518                         goto __error;
 519                 }
 520         }
 521
 522         /* we are allowed to call snd_card_register() many times */
 523         if (snd_card_register(chip->card) < 0) {
 524                 goto __error;
 525         }
 526
 527         usb_chip[chip->index] = chip;
 528         chip->num_interfaces++;
 529         chip->probing = 0;
 530         mutex_unlock(&register_mutex);
 531         return chip;
 532
 533  __error:
 534         if (chip) {
 535                 if (!chip->num_interfaces)
 536                         snd_card_free(chip->card);
 537                 chip->probing = 0;
 538         }
 539         mutex_unlock(&register_mutex);
 540  __err_val:
 541         return NULL;
 542 }
 543
 544 /*
 545  * we need to take care of counter, since disconnection can be called also
 546  * many times as well as usb_audio_probe().
 547  */
 548 static void snd_usb_audio_disconnect(struct usb_device *dev,
 549                                      struct snd_usb_audio *chip)
 550 {
 551         struct snd_card *card;
 552         struct list_head *p;
 553
 554         if (chip == (void *)-1L)
 555                 return;
 556
 557         card = chip->card;
 558         mutex_lock(&register_mutex);
 559         mutex_lock(&chip->shutdown_mutex);
 560         chip->shutdown = 1;
 561         chip->num_interfaces--;
 562         if (chip->num_interfaces <= 0) {
 563                 snd_card_disconnect(card);
 564                 /* release the pcm resources */
 565                 list_for_each(p, &chip->pcm_list) {
 566                         snd_usb_stream_disconnect(p);
 567                 }
 568                 /* release the midi resources */
 569                 list_for_each(p, &chip->midi_list) {
 570                         snd_usbmidi_disconnect(p);
 571                 }
 572                 /* release mixer resources */
 573                 list_for_each(p, &chip->mixer_list) {
 574                         snd_usb_mixer_disconnect(p);
 575                 }
 576                 usb_chip[chip->index] = NULL;
 577                 mutex_unlock(&chip->shutdown_mutex);
 578                 mutex_unlock(&register_mutex);
 579                 snd_card_free_when_closed(card);
 580         } else {
 581                 mutex_unlock(&chip->shutdown_mutex);
 582                 mutex_unlock(&register_mutex);
 583         }
 584 }
 585
 586 /*
 587  * new 2.5 USB kernel API
 588  */
 589 static int usb_audio_probe(struct usb_interface *intf,
 590                            const struct usb_device_id *id)
 591 {
 592         struct snd_usb_audio *chip;
 593         chip = snd_usb_audio_probe(interface_to_usbdev(intf), intf, id);
 594         if (chip) {
 595                 usb_set_intfdata(intf, chip);
 596                 return 0;
 597         } else
 598                 return -EIO;
 599 }
 600
 601 static void usb_audio_disconnect(struct usb_interface *intf)
 602 {
 603         snd_usb_audio_disconnect(interface_to_usbdev(intf),
 604                                  usb_get_intfdata(intf));
 605 }
 606
 607 #ifdef CONFIG_PM
 608
 609 int snd_usb_autoresume(struct snd_usb_audio *chip)
 610 {
 611         int err = -ENODEV;
 612
 613         if (!chip->shutdown && !chip->probing)
 614                 err = usb_autopm_get_interface(chip->pm_intf);
 615
 616         return err;
 617 }
 618
 619 void snd_usb_autosuspend(struct snd_usb_audio *chip)
 620 {
 621         if (!chip->shutdown && !chip->probing)
 622                 usb_autopm_put_interface(chip->pm_intf);
 623 }
 624
 625 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 626 {
 627         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 628         struct list_head *p;
 629         struct snd_usb_stream *as;
 630         struct usb_mixer_interface *mixer;
 631
 632         if (chip == (void *)-1L)
 633                 return 0;
 634
 635         if (!PMSG_IS_AUTO(message)) {
 636                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
 637                 if (!chip->num_suspended_intf++) {
 638                         list_for_each(p, &chip->pcm_list) {
 639                                 as = list_entry(p, struct snd_usb_stream, list);
 640                                 snd_pcm_suspend_all(as->pcm);
 641                         }
 642                 }
 643         } else {
 644                 /*
 645                  * otherwise we keep the rest of the system in the dark
 646                  * to keep this transparent
 647                  */
 648                 if (!chip->num_suspended_intf++)
 649                         chip->autosuspended = 1;
 650         }
 651
 652         list_for_each_entry(mixer, &chip->mixer_list, list)
 653                 snd_usb_mixer_inactivate(mixer);
 654
 655         return 0;
 656 }
 657
 658 static int usb_audio_resume(struct usb_interface *intf)
 659 {
 660         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 661         struct usb_mixer_interface *mixer;
 662         int err = 0;
 663
 664         if (chip == (void *)-1L)
 665                 return 0;
 666         if (--chip->num_suspended_intf)
 667                 return 0;
 668         /*
 669          * ALSA leaves material resumption to user space
 670          * we just notify and restart the mixers
 671          */
 672         list_for_each_entry(mixer, &chip->mixer_list, list) {
 673                 err = snd_usb_mixer_activate(mixer);
 674                 if (err < 0)
 675                         goto err_out;
 676         }
 677
 678         if (!chip->autosuspended)
 679                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
 680         chip->autosuspended = 0;
 681
 682 err_out:
 683         return err;
 684 }
 685 #else
 686 #define usb_audio_suspend       NULL
 687 #define usb_audio_resume        NULL
 688 #endif          /* CONFIG_PM */
 689
 690 static struct usb_device_id usb_audio_ids [] = {
 691 #include "quirks-table.h"
 692     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
 693       .bInterfaceClass = USB_CLASS_AUDIO,
 694       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
 695     { }                                         /* Terminating entry */
 696 };
 697
 698 MODULE_DEVICE_TABLE (usb, usb_audio_ids);
 699
 700 /*
 701  * entry point for linux usb interface
 702  */
 703
 704 static struct usb_driver usb_audio_driver = {
 705         .name =         "snd-usb-audio",
 706         .probe =        usb_audio_probe,
 707         .disconnect =   usb_audio_disconnect,
 708         .suspend =      usb_audio_suspend,
 709         .resume =       usb_audio_resume,
 710         .id_table =     usb_audio_ids,
 711         .supports_autosuspend = 1,
 712 };
 713
 714 static int __init snd_usb_audio_init(void)
 715 {
 716         if (nrpacks < 1 || nrpacks > MAX_PACKS) {
 717                 printk(KERN_WARNING "invalid nrpacks value.\n");
 718                 return -EINVAL;
 719         }
 720         return usb_register(&usb_audio_driver);
 721 }
 722
 723 static void __exit snd_usb_audio_cleanup(void)
 724 {
 725         usb_deregister(&usb_audio_driver);
 726 }
 727
 728 module_init(snd_usb_audio_init);
 729 module_exit(snd_usb_audio_cleanup);