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 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 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                 dev_err(&dev->dev, "%u:%d : does not exist\n",
 143                         ctrlif, interface);
 144                 return -EINVAL;
 145         }
 146
 147         alts = &iface->altsetting[0];
 148         altsd = get_iface_desc(alts);
 149
 150         /*
 151          * Android with both accessory and audio interfaces enabled gets the
 152          * interface numbers wrong.
 153          */
 154         if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
 155              chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
 156             interface == 0 &&
 157             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
 158             altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
 159                 interface = 2;
 160                 iface = usb_ifnum_to_if(dev, interface);
 161                 if (!iface)
 162                         return -EINVAL;
 163                 alts = &iface->altsetting[0];
 164                 altsd = get_iface_desc(alts);
 165         }
 166
 167         if (usb_interface_claimed(iface)) {
 168                 dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
 169                         ctrlif, interface);
 170                 return -EINVAL;
 171         }
 172
 173         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 174              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 175             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
 176                 int err = snd_usbmidi_create(chip->card, iface,
 177                                              &chip->midi_list, NULL);
 178                 if (err < 0) {
 179                         dev_err(&dev->dev,
 180                                 "%u:%d: cannot create sequencer device\n",
 181                                 ctrlif, interface);
 182                         return -EINVAL;
 183                 }
 184                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 185
 186                 return 0;
 187         }
 188
 189         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
 190              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
 191             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
 192                 dev_dbg(&dev->dev,
 193                         "%u:%d: skipping non-supported interface %d\n",
 194                         ctrlif, interface, altsd->bInterfaceClass);
 195                 /* skip non-supported classes */
 196                 return -EINVAL;
 197         }
 198
 199         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
 200                 dev_err(&dev->dev, "low speed audio streaming not supported\n");
 201                 return -EINVAL;
 202         }
 203
 204         if (! snd_usb_parse_audio_interface(chip, interface)) {
 205                 usb_set_interface(dev, interface, 0); /* reset the current interface */
 206                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
 207                 return -EINVAL;
 208         }
 209
 210         return 0;
 211 }
 212
 213 /*
 214  * parse audio control descriptor and create pcm/midi streams
 215  */
 216 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 217 {
 218         struct usb_device *dev = chip->dev;
 219         struct usb_host_interface *host_iface;
 220         struct usb_interface_descriptor *altsd;
 221         void *control_header;
 222         int i, protocol;
 223
 224         /* find audiocontrol interface */
 225         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
 226         control_header = snd_usb_find_csint_desc(host_iface->extra,
 227                                                  host_iface->extralen,
 228                                                  NULL, UAC_HEADER);
 229         altsd = get_iface_desc(host_iface);
 230         protocol = altsd->bInterfaceProtocol;
 231
 232         if (!control_header) {
 233                 dev_err(&dev->dev, "cannot find UAC_HEADER\n");
 234                 return -EINVAL;
 235         }
 236
 237         switch (protocol) {
 238         default:
 239                 dev_warn(&dev->dev,
 240                          "unknown interface protocol %#02x, assuming v1\n",
 241                          protocol);
 242                 /* fall through */
 243
 244         case UAC_VERSION_1: {
 245                 struct uac1_ac_header_descriptor *h1 = control_header;
 246
 247                 if (!h1->bInCollection) {
 248                         dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
 249                         return -EINVAL;
 250                 }
 251
 252                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
 253                         dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
 254                         return -EINVAL;
 255                 }
 256
 257                 for (i = 0; i < h1->bInCollection; i++)
 258                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
 259
 260                 break;
 261         }
 262
 263         case UAC_VERSION_2: {
 264                 struct usb_interface_assoc_descriptor *assoc =
 265                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
 266
 267                 if (!assoc) {
 268                         /*
 269                          * Firmware writers cannot count to three.  So to find
 270                          * the IAD on the NuForce UDH-100, also check the next
 271                          * interface.
 272                          */
 273                         struct usb_interface *iface =
 274                                 usb_ifnum_to_if(dev, ctrlif + 1);
 275                         if (iface &&
 276                             iface->intf_assoc &&
 277                             iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
 278                             iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
 279                                 assoc = iface->intf_assoc;
 280                 }
 281
 282                 if (!assoc) {
 283                         dev_err(&dev->dev, "Audio class v2 interfaces need an interface association\n");
 284                         return -EINVAL;
 285                 }
 286
 287                 for (i = 0; i < assoc->bInterfaceCount; i++) {
 288                         int intf = assoc->bFirstInterface + i;
 289
 290                         if (intf != ctrlif)
 291                                 snd_usb_create_stream(chip, ctrlif, intf);
 292                 }
 293
 294                 break;
 295         }
 296         }
 297
 298         return 0;
 299 }
 300
 301 /*
 302  * free the chip instance
 303  *
 304  * here we have to do not much, since pcm and controls are already freed
 305  *
 306  */
 307
 308 static int snd_usb_audio_free(struct snd_usb_audio *chip)
 309 {
 310         mutex_destroy(&chip->mutex);
 311         kfree(chip);
 312         return 0;
 313 }
 314
 315 static int snd_usb_audio_dev_free(struct snd_device *device)
 316 {
 317         struct snd_usb_audio *chip = device->device_data;
 318         return snd_usb_audio_free(chip);
 319 }
 320
 321 static void remove_trailing_spaces(char *str)
 322 {
 323         char *p;
 324
 325         if (!*str)
 326                 return;
 327         for (p = str + strlen(str) - 1; p >= str && isspace(*p); p--)
 328                 *p = 0;
 329 }
 330
 331 /*
 332  * create a chip instance and set its names.
 333  */
 334 static int snd_usb_audio_create(struct usb_interface *intf,
 335                                 struct usb_device *dev, int idx,
 336                                 const struct snd_usb_audio_quirk *quirk,
 337                                 struct snd_usb_audio **rchip)
 338 {
 339         struct snd_card *card;
 340         struct snd_usb_audio *chip;
 341         int err, len;
 342         char component[14];
 343         static struct snd_device_ops ops = {
 344                 .dev_free =     snd_usb_audio_dev_free,
 345         };
 346
 347         *rchip = NULL;
 348
 349         switch (snd_usb_get_speed(dev)) {
 350         case USB_SPEED_LOW:
 351         case USB_SPEED_FULL:
 352         case USB_SPEED_HIGH:
 353         case USB_SPEED_WIRELESS:
 354         case USB_SPEED_SUPER:
 355                 break;
 356         default:
 357                 dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
 358                 return -ENXIO;
 359         }
 360
 361         err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
 362                            0, &card);
 363         if (err < 0) {
 364                 dev_err(&dev->dev, "cannot create card instance %d\n", idx);
 365                 return err;
 366         }
 367
 368         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 369         if (! chip) {
 370                 snd_card_free(card);
 371                 return -ENOMEM;
 372         }
 373
 374         mutex_init(&chip->mutex);
 375         init_rwsem(&chip->shutdown_rwsem);
 376         chip->index = idx;
 377         chip->dev = dev;
 378         chip->card = card;
 379         chip->setup = device_setup[idx];
 380         chip->autoclock = autoclock;
 381         chip->probing = 1;
 382
 383         chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 384                               le16_to_cpu(dev->descriptor.idProduct));
 385         INIT_LIST_HEAD(&chip->pcm_list);
 386         INIT_LIST_HEAD(&chip->ep_list);
 387         INIT_LIST_HEAD(&chip->midi_list);
 388         INIT_LIST_HEAD(&chip->mixer_list);
 389
 390         if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
 391                 snd_usb_audio_free(chip);
 392                 snd_card_free(card);
 393                 return err;
 394         }
 395
 396         strcpy(card->driver, "USB-Audio");
 397         sprintf(component, "USB%04x:%04x",
 398                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
 399         snd_component_add(card, component);
 400
 401         /* retrieve the device string as shortname */
 402         if (quirk && quirk->product_name && *quirk->product_name) {
 403                 strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
 404         } else {
 405                 if (!dev->descriptor.iProduct ||
 406                     usb_string(dev, dev->descriptor.iProduct,
 407                     card->shortname, sizeof(card->shortname)) <= 0) {
 408                         /* no name available from anywhere, so use ID */
 409                         sprintf(card->shortname, "USB Device %#04x:%#04x",
 410                                 USB_ID_VENDOR(chip->usb_id),
 411                                 USB_ID_PRODUCT(chip->usb_id));
 412                 }
 413         }
 414         remove_trailing_spaces(card->shortname);
 415
 416         /* retrieve the vendor and device strings as longname */
 417         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
 418                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
 419         } else {
 420                 if (dev->descriptor.iManufacturer)
 421                         len = usb_string(dev, dev->descriptor.iManufacturer,
 422                                          card->longname, sizeof(card->longname));
 423                 else
 424                         len = 0;
 425                 /* we don't really care if there isn't any vendor string */
 426         }
 427         if (len > 0) {
 428                 remove_trailing_spaces(card->longname);
 429                 if (*card->longname)
 430                         strlcat(card->longname, " ", sizeof(card->longname));
 431         }
 432
 433         strlcat(card->longname, card->shortname, sizeof(card->longname));
 434
 435         len = strlcat(card->longname, " at ", sizeof(card->longname));
 436
 437         if (len < sizeof(card->longname))
 438                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
 439
 440         switch (snd_usb_get_speed(dev)) {
 441         case USB_SPEED_LOW:
 442                 strlcat(card->longname, ", low speed", sizeof(card->longname));
 443                 break;
 444         case USB_SPEED_FULL:
 445                 strlcat(card->longname, ", full speed", sizeof(card->longname));
 446                 break;
 447         case USB_SPEED_HIGH:
 448                 strlcat(card->longname, ", high speed", sizeof(card->longname));
 449                 break;
 450         case USB_SPEED_SUPER:
 451                 strlcat(card->longname, ", super speed", sizeof(card->longname));
 452                 break;
 453         default:
 454                 break;
 455         }
 456
 457         snd_usb_audio_create_proc(chip);
 458
 459         *rchip = chip;
 460         return 0;
 461 }
 462
 463 /*
 464  * probe the active usb device
 465  *
 466  * note that this can be called multiple times per a device, when it
 467  * includes multiple audio control interfaces.
 468  *
 469  * thus we check the usb device pointer and creates the card instance
 470  * only at the first time.  the successive calls of this function will
 471  * append the pcm interface to the corresponding card.
 472  */
 473 static struct snd_usb_audio *
 474 snd_usb_audio_probe(struct usb_device *dev,
 475                     struct usb_interface *intf,
 476                     const struct usb_device_id *usb_id)
 477 {
 478         const struct snd_usb_audio_quirk *quirk = (const struct snd_usb_audio_quirk *)usb_id->driver_info;
 479         int i, err;
 480         struct snd_usb_audio *chip;
 481         struct usb_host_interface *alts;
 482         int ifnum;
 483         u32 id;
 484
 485         alts = &intf->altsetting[0];
 486         ifnum = get_iface_desc(alts)->bInterfaceNumber;
 487         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
 488                     le16_to_cpu(dev->descriptor.idProduct));
 489         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
 490                 goto __err_val;
 491
 492         if (snd_usb_apply_boot_quirk(dev, intf, quirk) < 0)
 493                 goto __err_val;
 494
 495         /*
 496          * found a config.  now register to ALSA
 497          */
 498
 499         /* check whether it's already registered */
 500         chip = NULL;
 501         mutex_lock(&register_mutex);
 502         for (i = 0; i < SNDRV_CARDS; i++) {
 503                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
 504                         if (usb_chip[i]->shutdown) {
 505                                 dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
 506                                 goto __error;
 507                         }
 508                         chip = usb_chip[i];
 509                         chip->probing = 1;
 510                         break;
 511                 }
 512         }
 513         if (! chip) {
 514                 /* it's a fresh one.
 515                  * now look for an empty slot and create a new card instance
 516                  */
 517                 for (i = 0; i < SNDRV_CARDS; i++)
 518                         if (enable[i] && ! usb_chip[i] &&
 519                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
 520                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
 521                                 if (snd_usb_audio_create(intf, dev, i, quirk,
 522                                                          &chip) < 0) {
 523                                         goto __error;
 524                                 }
 525                                 chip->pm_intf = intf;
 526                                 break;
 527                         }
 528                 if (!chip) {
 529                         dev_err(&dev->dev, "no available usb audio device\n");
 530                         goto __error;
 531                 }
 532         }
 533
 534         /*
 535          * For devices with more than one control interface, we assume the
 536          * first contains the audio controls. We might need a more specific
 537          * check here in the future.
 538          */
 539         if (!chip->ctrl_intf)
 540                 chip->ctrl_intf = alts;
 541
 542         chip->txfr_quirk = 0;
 543         err = 1; /* continue */
 544         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
 545                 /* need some special handlings */
 546                 if ((err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk)) < 0)
 547                         goto __error;
 548         }
 549
 550         if (err > 0) {
 551                 /* create normal USB audio interfaces */
 552                 if (snd_usb_create_streams(chip, ifnum) < 0 ||
 553                     snd_usb_create_mixer(chip, ifnum, ignore_ctl_error) < 0) {
 554                         goto __error;
 555                 }
 556         }
 557
 558         /* we are allowed to call snd_card_register() many times */
 559         if (snd_card_register(chip->card) < 0) {
 560                 goto __error;
 561         }
 562
 563         usb_chip[chip->index] = chip;
 564         chip->num_interfaces++;
 565         chip->probing = 0;
 566         mutex_unlock(&register_mutex);
 567         return chip;
 568
 569  __error:
 570         if (chip) {
 571                 if (!chip->num_interfaces)
 572                         snd_card_free(chip->card);
 573                 chip->probing = 0;
 574         }
 575         mutex_unlock(&register_mutex);
 576  __err_val:
 577         return NULL;
 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 snd_usb_audio_disconnect(struct usb_device *dev,
 585                                      struct snd_usb_audio *chip)
 586 {
 587         struct snd_card *card;
 588         struct list_head *p, *n;
 589
 590         if (chip == (void *)-1L)
 591                 return;
 592
 593         card = chip->card;
 594         down_write(&chip->shutdown_rwsem);
 595         chip->shutdown = 1;
 596         up_write(&chip->shutdown_rwsem);
 597
 598         mutex_lock(&register_mutex);
 599         chip->num_interfaces--;
 600         if (chip->num_interfaces <= 0) {
 601                 snd_card_disconnect(card);
 602                 /* release the pcm resources */
 603                 list_for_each(p, &chip->pcm_list) {
 604                         snd_usb_stream_disconnect(p);
 605                 }
 606                 /* release the endpoint resources */
 607                 list_for_each_safe(p, n, &chip->ep_list) {
 608                         snd_usb_endpoint_free(p);
 609                 }
 610                 /* release the midi resources */
 611                 list_for_each(p, &chip->midi_list) {
 612                         snd_usbmidi_disconnect(p);
 613                 }
 614                 /* release mixer resources */
 615                 list_for_each(p, &chip->mixer_list) {
 616                         snd_usb_mixer_disconnect(p);
 617                 }
 618                 usb_chip[chip->index] = NULL;
 619                 mutex_unlock(&register_mutex);
 620                 snd_card_free_when_closed(card);
 621         } else {
 622                 mutex_unlock(&register_mutex);
 623         }
 624 }
 625
 626 /*
 627  * new 2.5 USB kernel API
 628  */
 629 static int usb_audio_probe(struct usb_interface *intf,
 630                            const struct usb_device_id *id)
 631 {
 632         struct snd_usb_audio *chip;
 633         chip = snd_usb_audio_probe(interface_to_usbdev(intf), intf, id);
 634         if (chip) {
 635                 usb_set_intfdata(intf, chip);
 636                 return 0;
 637         } else
 638                 return -EIO;
 639 }
 640
 641 static void usb_audio_disconnect(struct usb_interface *intf)
 642 {
 643         snd_usb_audio_disconnect(interface_to_usbdev(intf),
 644                                  usb_get_intfdata(intf));
 645 }
 646
 647 #ifdef CONFIG_PM
 648
 649 int snd_usb_autoresume(struct snd_usb_audio *chip)
 650 {
 651         int err = -ENODEV;
 652
 653         down_read(&chip->shutdown_rwsem);
 654         if (chip->probing)
 655                 err = 0;
 656         else if (!chip->shutdown)
 657                 err = usb_autopm_get_interface(chip->pm_intf);
 658         up_read(&chip->shutdown_rwsem);
 659
 660         return err;
 661 }
 662
 663 void snd_usb_autosuspend(struct snd_usb_audio *chip)
 664 {
 665         down_read(&chip->shutdown_rwsem);
 666         if (!chip->shutdown && !chip->probing)
 667                 usb_autopm_put_interface(chip->pm_intf);
 668         up_read(&chip->shutdown_rwsem);
 669 }
 670
 671 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 672 {
 673         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 674         struct snd_usb_stream *as;
 675         struct usb_mixer_interface *mixer;
 676
 677         if (chip == (void *)-1L)
 678                 return 0;
 679
 680         if (!PMSG_IS_AUTO(message)) {
 681                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
 682                 if (!chip->num_suspended_intf++) {
 683                         list_for_each_entry(as, &chip->pcm_list, list) {
 684                                 snd_pcm_suspend_all(as->pcm);
 685                                 as->substream[0].need_setup_ep =
 686                                         as->substream[1].need_setup_ep = true;
 687                         }
 688                 }
 689         } else {
 690                 /*
 691                  * otherwise we keep the rest of the system in the dark
 692                  * to keep this transparent
 693                  */
 694                 if (!chip->num_suspended_intf++)
 695                         chip->autosuspended = 1;
 696         }
 697
 698         list_for_each_entry(mixer, &chip->mixer_list, list)
 699                 snd_usb_mixer_suspend(mixer);
 700
 701         return 0;
 702 }
 703
 704 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
 705 {
 706         struct snd_usb_audio *chip = usb_get_intfdata(intf);
 707         struct usb_mixer_interface *mixer;
 708         int err = 0;
 709
 710         if (chip == (void *)-1L)
 711                 return 0;
 712         if (--chip->num_suspended_intf)
 713                 return 0;
 714         /*
 715          * ALSA leaves material resumption to user space
 716          * we just notify and restart the mixers
 717          */
 718         list_for_each_entry(mixer, &chip->mixer_list, list) {
 719                 err = snd_usb_mixer_resume(mixer, reset_resume);
 720                 if (err < 0)
 721                         goto err_out;
 722         }
 723
 724         if (!chip->autosuspended)
 725                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
 726         chip->autosuspended = 0;
 727
 728 err_out:
 729         return err;
 730 }
 731
 732 static int usb_audio_resume(struct usb_interface *intf)
 733 {
 734         return __usb_audio_resume(intf, false);
 735 }
 736
 737 static int usb_audio_reset_resume(struct usb_interface *intf)
 738 {
 739         return __usb_audio_resume(intf, true);
 740 }
 741 #else
 742 #define usb_audio_suspend       NULL
 743 #define usb_audio_resume        NULL
 744 #define usb_audio_reset_resume  NULL
 745 #endif          /* CONFIG_PM */
 746
 747 static struct usb_device_id usb_audio_ids [] = {
 748 #include "quirks-table.h"
 749     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
 750       .bInterfaceClass = USB_CLASS_AUDIO,
 751       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
 752     { }                                         /* Terminating entry */
 753 };
 754 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
 755
 756 /*
 757  * entry point for linux usb interface
 758  */
 759
 760 static struct usb_driver usb_audio_driver = {
 761         .name =         "snd-usb-audio",
 762         .probe =        usb_audio_probe,
 763         .disconnect =   usb_audio_disconnect,
 764         .suspend =      usb_audio_suspend,
 765         .resume =       usb_audio_resume,
 766         .reset_resume = usb_audio_reset_resume,
 767         .id_table =     usb_audio_ids,
 768         .supports_autosuspend = 1,
 769 };
 770
 771 module_usb_driver(usb_audio_driver);