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(®ister_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(®ister_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(®ister_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(®ister_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(®ister_mutex); 596 snd_card_free_when_closed(card); 597 } else { 598 mutex_unlock(®ister_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); 752