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