ALSA: hda - Enabling Realtek ALC 671 codec
[linux-2.6.git] / 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         init_rwsem(&chip->shutdown_rwsem);
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         down_write(&chip->shutdown_rwsem);
559         chip->shutdown = 1;
560         up_write(&chip->shutdown_rwsem);
561
562         mutex_lock(&register_mutex);
563         chip->num_interfaces--;
564         if (chip->num_interfaces <= 0) {
565                 snd_card_disconnect(card);
566                 /* release the pcm resources */
567                 list_for_each(p, &chip->pcm_list) {
568                         snd_usb_stream_disconnect(p);
569                 }
570                 /* release the midi resources */
571                 list_for_each(p, &chip->midi_list) {
572                         snd_usbmidi_disconnect(p);
573                 }
574                 /* release mixer resources */
575                 list_for_each(p, &chip->mixer_list) {
576                         snd_usb_mixer_disconnect(p);
577                 }
578                 usb_chip[chip->index] = NULL;
579                 mutex_unlock(&register_mutex);
580                 snd_card_free_when_closed(card);
581         } else {
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         down_read(&chip->shutdown_rwsem);
614         if (!chip->shutdown && !chip->probing)
615                 err = usb_autopm_get_interface(chip->pm_intf);
616         up_read(&chip->shutdown_rwsem);
617
618         return err;
619 }
620
621 void snd_usb_autosuspend(struct snd_usb_audio *chip)
622 {
623         down_read(&chip->shutdown_rwsem);
624         if (!chip->shutdown && !chip->probing)
625                 usb_autopm_put_interface(chip->pm_intf);
626         up_read(&chip->shutdown_rwsem);
627 }
628
629 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
630 {
631         struct snd_usb_audio *chip = usb_get_intfdata(intf);
632         struct list_head *p;
633         struct snd_usb_stream *as;
634         struct usb_mixer_interface *mixer;
635
636         if (chip == (void *)-1L)
637                 return 0;
638
639         if (!PMSG_IS_AUTO(message)) {
640                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
641                 if (!chip->num_suspended_intf++) {
642                         list_for_each(p, &chip->pcm_list) {
643                                 as = list_entry(p, struct snd_usb_stream, list);
644                                 snd_pcm_suspend_all(as->pcm);
645                         }
646                 }
647         } else {
648                 /*
649                  * otherwise we keep the rest of the system in the dark
650                  * to keep this transparent
651                  */
652                 if (!chip->num_suspended_intf++)
653                         chip->autosuspended = 1;
654         }
655
656         list_for_each_entry(mixer, &chip->mixer_list, list)
657                 snd_usb_mixer_inactivate(mixer);
658
659         return 0;
660 }
661
662 static int usb_audio_resume(struct usb_interface *intf)
663 {
664         struct snd_usb_audio *chip = usb_get_intfdata(intf);
665         struct usb_mixer_interface *mixer;
666         int err = 0;
667
668         if (chip == (void *)-1L)
669                 return 0;
670         if (--chip->num_suspended_intf)
671                 return 0;
672         /*
673          * ALSA leaves material resumption to user space
674          * we just notify and restart the mixers
675          */
676         list_for_each_entry(mixer, &chip->mixer_list, list) {
677                 err = snd_usb_mixer_activate(mixer);
678                 if (err < 0)
679                         goto err_out;
680         }
681
682         if (!chip->autosuspended)
683                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
684         chip->autosuspended = 0;
685
686 err_out:
687         return err;
688 }
689 #else
690 #define usb_audio_suspend       NULL
691 #define usb_audio_resume        NULL
692 #endif          /* CONFIG_PM */
693
694 static struct usb_device_id usb_audio_ids [] = {
695 #include "quirks-table.h"
696     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
697       .bInterfaceClass = USB_CLASS_AUDIO,
698       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
699     { }                                         /* Terminating entry */
700 };
701
702 MODULE_DEVICE_TABLE (usb, usb_audio_ids);
703
704 /*
705  * entry point for linux usb interface
706  */
707
708 static struct usb_driver usb_audio_driver = {
709         .name =         "snd-usb-audio",
710         .probe =        usb_audio_probe,
711         .disconnect =   usb_audio_disconnect,
712         .suspend =      usb_audio_suspend,
713         .resume =       usb_audio_resume,
714         .id_table =     usb_audio_ids,
715         .supports_autosuspend = 1,
716 };
717
718 static int __init snd_usb_audio_init(void)
719 {
720         if (nrpacks < 1 || nrpacks > MAX_PACKS) {
721                 printk(KERN_WARNING "invalid nrpacks value.\n");
722                 return -EINVAL;
723         }
724         return usb_register(&usb_audio_driver);
725 }
726
727 static void __exit snd_usb_audio_cleanup(void)
728 {
729         usb_deregister(&usb_audio_driver);
730 }
731
732 module_init(snd_usb_audio_init);
733 module_exit(snd_usb_audio_cleanup);