Merge branch 'next' into for-linus
[pandora-kernel.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                 subs->interface = -1;
135                 subs->data_endpoint = NULL;
136                 subs->sync_endpoint = NULL;
137         }
138 }
139
140 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
141 {
142         struct usb_device *dev = chip->dev;
143         struct usb_host_interface *alts;
144         struct usb_interface_descriptor *altsd;
145         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
146
147         if (!iface) {
148                 snd_printk(KERN_ERR "%d:%u:%d : does not exist\n",
149                            dev->devnum, ctrlif, interface);
150                 return -EINVAL;
151         }
152
153         if (usb_interface_claimed(iface)) {
154                 snd_printdd(KERN_INFO "%d:%d:%d: skipping, already claimed\n",
155                                                 dev->devnum, ctrlif, interface);
156                 return -EINVAL;
157         }
158
159         alts = &iface->altsetting[0];
160         altsd = get_iface_desc(alts);
161         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
162              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
163             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
164                 int err = snd_usbmidi_create(chip->card, iface,
165                                              &chip->midi_list, NULL);
166                 if (err < 0) {
167                         snd_printk(KERN_ERR "%d:%u:%d: cannot create sequencer device\n",
168                                                 dev->devnum, ctrlif, interface);
169                         return -EINVAL;
170                 }
171                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
172
173                 return 0;
174         }
175
176         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
177              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
178             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
179                 snd_printdd(KERN_ERR "%d:%u:%d: skipping non-supported interface %d\n",
180                                         dev->devnum, ctrlif, interface, altsd->bInterfaceClass);
181                 /* skip non-supported classes */
182                 return -EINVAL;
183         }
184
185         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
186                 snd_printk(KERN_ERR "low speed audio streaming not supported\n");
187                 return -EINVAL;
188         }
189
190         if (! snd_usb_parse_audio_interface(chip, interface)) {
191                 usb_set_interface(dev, interface, 0); /* reset the current interface */
192                 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
193                 return -EINVAL;
194         }
195
196         return 0;
197 }
198
199 /*
200  * parse audio control descriptor and create pcm/midi streams
201  */
202 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
203 {
204         struct usb_device *dev = chip->dev;
205         struct usb_host_interface *host_iface;
206         struct usb_interface_descriptor *altsd;
207         void *control_header;
208         int i, protocol;
209
210         /* find audiocontrol interface */
211         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
212         control_header = snd_usb_find_csint_desc(host_iface->extra,
213                                                  host_iface->extralen,
214                                                  NULL, UAC_HEADER);
215         altsd = get_iface_desc(host_iface);
216         protocol = altsd->bInterfaceProtocol;
217
218         if (!control_header) {
219                 snd_printk(KERN_ERR "cannot find UAC_HEADER\n");
220                 return -EINVAL;
221         }
222
223         switch (protocol) {
224         default:
225                 snd_printdd(KERN_WARNING "unknown interface protocol %#02x, assuming v1\n",
226                             protocol);
227                 /* fall through */
228
229         case UAC_VERSION_1: {
230                 struct uac1_ac_header_descriptor *h1 = control_header;
231
232                 if (!h1->bInCollection) {
233                         snd_printk(KERN_INFO "skipping empty audio interface (v1)\n");
234                         return -EINVAL;
235                 }
236
237                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
238                         snd_printk(KERN_ERR "invalid UAC_HEADER (v1)\n");
239                         return -EINVAL;
240                 }
241
242                 for (i = 0; i < h1->bInCollection; i++)
243                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
244
245                 break;
246         }
247
248         case UAC_VERSION_2: {
249                 struct usb_interface_assoc_descriptor *assoc =
250                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
251
252                 if (!assoc) {
253                         snd_printk(KERN_ERR "Audio class v2 interfaces need an interface association\n");
254                         return -EINVAL;
255                 }
256
257                 for (i = 0; i < assoc->bInterfaceCount; i++) {
258                         int intf = assoc->bFirstInterface + i;
259
260                         if (intf != ctrlif)
261                                 snd_usb_create_stream(chip, ctrlif, intf);
262                 }
263
264                 break;
265         }
266         }
267
268         return 0;
269 }
270
271 /*
272  * free the chip instance
273  *
274  * here we have to do not much, since pcm and controls are already freed
275  *
276  */
277
278 static int snd_usb_audio_free(struct snd_usb_audio *chip)
279 {
280         mutex_destroy(&chip->mutex);
281         kfree(chip);
282         return 0;
283 }
284
285 static int snd_usb_audio_dev_free(struct snd_device *device)
286 {
287         struct snd_usb_audio *chip = device->device_data;
288         return snd_usb_audio_free(chip);
289 }
290
291 static void remove_trailing_spaces(char *str)
292 {
293         char *p;
294
295         if (!*str)
296                 return;
297         for (p = str + strlen(str) - 1; p >= str && isspace(*p); p--)
298                 *p = 0;
299 }
300
301 /*
302  * create a chip instance and set its names.
303  */
304 static int snd_usb_audio_create(struct usb_device *dev, int idx,
305                                 const struct snd_usb_audio_quirk *quirk,
306                                 struct snd_usb_audio **rchip)
307 {
308         struct snd_card *card;
309         struct snd_usb_audio *chip;
310         int err, len;
311         char component[14];
312         static struct snd_device_ops ops = {
313                 .dev_free =     snd_usb_audio_dev_free,
314         };
315
316         *rchip = NULL;
317
318         switch (snd_usb_get_speed(dev)) {
319         case USB_SPEED_LOW:
320         case USB_SPEED_FULL:
321         case USB_SPEED_HIGH:
322         case USB_SPEED_SUPER:
323                 break;
324         default:
325                 snd_printk(KERN_ERR "unknown device speed %d\n", snd_usb_get_speed(dev));
326                 return -ENXIO;
327         }
328
329         err = snd_card_create(index[idx], id[idx], THIS_MODULE, 0, &card);
330         if (err < 0) {
331                 snd_printk(KERN_ERR "cannot create card instance %d\n", idx);
332                 return err;
333         }
334
335         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
336         if (! chip) {
337                 snd_card_free(card);
338                 return -ENOMEM;
339         }
340
341         mutex_init(&chip->mutex);
342         mutex_init(&chip->shutdown_mutex);
343         chip->index = idx;
344         chip->dev = dev;
345         chip->card = card;
346         chip->setup = device_setup[idx];
347         chip->nrpacks = nrpacks;
348         chip->async_unlink = async_unlink;
349         chip->probing = 1;
350
351         chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
352                               le16_to_cpu(dev->descriptor.idProduct));
353         INIT_LIST_HEAD(&chip->pcm_list);
354         INIT_LIST_HEAD(&chip->ep_list);
355         INIT_LIST_HEAD(&chip->midi_list);
356         INIT_LIST_HEAD(&chip->mixer_list);
357
358         if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
359                 snd_usb_audio_free(chip);
360                 snd_card_free(card);
361                 return err;
362         }
363
364         strcpy(card->driver, "USB-Audio");
365         sprintf(component, "USB%04x:%04x",
366                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
367         snd_component_add(card, component);
368
369         /* retrieve the device string as shortname */
370         if (quirk && quirk->product_name && *quirk->product_name) {
371                 strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
372         } else {
373                 if (!dev->descriptor.iProduct ||
374                     usb_string(dev, dev->descriptor.iProduct,
375                     card->shortname, sizeof(card->shortname)) <= 0) {
376                         /* no name available from anywhere, so use ID */
377                         sprintf(card->shortname, "USB Device %#04x:%#04x",
378                                 USB_ID_VENDOR(chip->usb_id),
379                                 USB_ID_PRODUCT(chip->usb_id));
380                 }
381         }
382         remove_trailing_spaces(card->shortname);
383
384         /* retrieve the vendor and device strings as longname */
385         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
386                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
387         } else {
388                 if (dev->descriptor.iManufacturer)
389                         len = usb_string(dev, dev->descriptor.iManufacturer,
390                                          card->longname, sizeof(card->longname));
391                 else
392                         len = 0;
393                 /* we don't really care if there isn't any vendor string */
394         }
395         if (len > 0) {
396                 remove_trailing_spaces(card->longname);
397                 if (*card->longname)
398                         strlcat(card->longname, " ", sizeof(card->longname));
399         }
400
401         strlcat(card->longname, card->shortname, sizeof(card->longname));
402
403         len = strlcat(card->longname, " at ", sizeof(card->longname));
404
405         if (len < sizeof(card->longname))
406                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
407
408         switch (snd_usb_get_speed(dev)) {
409         case USB_SPEED_LOW:
410                 strlcat(card->longname, ", low speed", sizeof(card->longname));
411                 break;
412         case USB_SPEED_FULL:
413                 strlcat(card->longname, ", full speed", sizeof(card->longname));
414                 break;
415         case USB_SPEED_HIGH:
416                 strlcat(card->longname, ", high speed", sizeof(card->longname));
417                 break;
418         case USB_SPEED_SUPER:
419                 strlcat(card->longname, ", super speed", sizeof(card->longname));
420                 break;
421         default:
422                 break;
423         }
424
425         snd_usb_audio_create_proc(chip);
426
427         *rchip = chip;
428         return 0;
429 }
430
431 /*
432  * probe the active usb device
433  *
434  * note that this can be called multiple times per a device, when it
435  * includes multiple audio control interfaces.
436  *
437  * thus we check the usb device pointer and creates the card instance
438  * only at the first time.  the successive calls of this function will
439  * append the pcm interface to the corresponding card.
440  */
441 static struct snd_usb_audio *
442 snd_usb_audio_probe(struct usb_device *dev,
443                     struct usb_interface *intf,
444                     const struct usb_device_id *usb_id)
445 {
446         const struct snd_usb_audio_quirk *quirk = (const struct snd_usb_audio_quirk *)usb_id->driver_info;
447         int i, err;
448         struct snd_usb_audio *chip;
449         struct usb_host_interface *alts;
450         int ifnum;
451         u32 id;
452
453         alts = &intf->altsetting[0];
454         ifnum = get_iface_desc(alts)->bInterfaceNumber;
455         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
456                     le16_to_cpu(dev->descriptor.idProduct));
457         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
458                 goto __err_val;
459
460         if (snd_usb_apply_boot_quirk(dev, intf, quirk) < 0)
461                 goto __err_val;
462
463         /*
464          * found a config.  now register to ALSA
465          */
466
467         /* check whether it's already registered */
468         chip = NULL;
469         mutex_lock(&register_mutex);
470         for (i = 0; i < SNDRV_CARDS; i++) {
471                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
472                         if (usb_chip[i]->shutdown) {
473                                 snd_printk(KERN_ERR "USB device is in the shutdown state, cannot create a card instance\n");
474                                 goto __error;
475                         }
476                         chip = usb_chip[i];
477                         chip->probing = 1;
478                         break;
479                 }
480         }
481         if (! chip) {
482                 /* it's a fresh one.
483                  * now look for an empty slot and create a new card instance
484                  */
485                 for (i = 0; i < SNDRV_CARDS; i++)
486                         if (enable[i] && ! usb_chip[i] &&
487                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
488                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
489                                 if (snd_usb_audio_create(dev, i, quirk, &chip) < 0) {
490                                         goto __error;
491                                 }
492                                 snd_card_set_dev(chip->card, &intf->dev);
493                                 chip->pm_intf = intf;
494                                 break;
495                         }
496                 if (!chip) {
497                         printk(KERN_ERR "no available usb audio device\n");
498                         goto __error;
499                 }
500         }
501
502         /*
503          * For devices with more than one control interface, we assume the
504          * first contains the audio controls. We might need a more specific
505          * check here in the future.
506          */
507         if (!chip->ctrl_intf)
508                 chip->ctrl_intf = alts;
509
510         chip->txfr_quirk = 0;
511         err = 1; /* continue */
512         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
513                 /* need some special handlings */
514                 if ((err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk)) < 0)
515                         goto __error;
516         }
517
518         if (err > 0) {
519                 /* create normal USB audio interfaces */
520                 if (snd_usb_create_streams(chip, ifnum) < 0 ||
521                     snd_usb_create_mixer(chip, ifnum, ignore_ctl_error) < 0) {
522                         goto __error;
523                 }
524         }
525
526         /* we are allowed to call snd_card_register() many times */
527         if (snd_card_register(chip->card) < 0) {
528                 goto __error;
529         }
530
531         usb_chip[chip->index] = chip;
532         chip->num_interfaces++;
533         chip->probing = 0;
534         mutex_unlock(&register_mutex);
535         return chip;
536
537  __error:
538         if (chip) {
539                 if (!chip->num_interfaces)
540                         snd_card_free(chip->card);
541                 chip->probing = 0;
542         }
543         mutex_unlock(&register_mutex);
544  __err_val:
545         return NULL;
546 }
547
548 /*
549  * we need to take care of counter, since disconnection can be called also
550  * many times as well as usb_audio_probe().
551  */
552 static void snd_usb_audio_disconnect(struct usb_device *dev,
553                                      struct snd_usb_audio *chip)
554 {
555         struct snd_card *card;
556         struct list_head *p, *n;
557
558         if (chip == (void *)-1L)
559                 return;
560
561         card = chip->card;
562         mutex_lock(&register_mutex);
563         mutex_lock(&chip->shutdown_mutex);
564         chip->shutdown = 1;
565         chip->num_interfaces--;
566         if (chip->num_interfaces <= 0) {
567                 snd_card_disconnect(card);
568                 /* release the pcm resources */
569                 list_for_each(p, &chip->pcm_list) {
570                         snd_usb_stream_disconnect(p);
571                 }
572                 /* release the endpoint resources */
573                 list_for_each_safe(p, n, &chip->ep_list) {
574                         snd_usb_endpoint_free(p);
575                 }
576                 /* release the midi resources */
577                 list_for_each(p, &chip->midi_list) {
578                         snd_usbmidi_disconnect(p);
579                 }
580                 /* release mixer resources */
581                 list_for_each(p, &chip->mixer_list) {
582                         snd_usb_mixer_disconnect(p);
583                 }
584                 usb_chip[chip->index] = NULL;
585                 mutex_unlock(&chip->shutdown_mutex);
586                 mutex_unlock(&register_mutex);
587                 snd_card_free_when_closed(card);
588         } else {
589                 mutex_unlock(&chip->shutdown_mutex);
590                 mutex_unlock(&register_mutex);
591         }
592 }
593
594 /*
595  * new 2.5 USB kernel API
596  */
597 static int usb_audio_probe(struct usb_interface *intf,
598                            const struct usb_device_id *id)
599 {
600         struct snd_usb_audio *chip;
601         chip = snd_usb_audio_probe(interface_to_usbdev(intf), intf, id);
602         if (chip) {
603                 usb_set_intfdata(intf, chip);
604                 return 0;
605         } else
606                 return -EIO;
607 }
608
609 static void usb_audio_disconnect(struct usb_interface *intf)
610 {
611         snd_usb_audio_disconnect(interface_to_usbdev(intf),
612                                  usb_get_intfdata(intf));
613 }
614
615 #ifdef CONFIG_PM
616
617 int snd_usb_autoresume(struct snd_usb_audio *chip)
618 {
619         int err = -ENODEV;
620
621         if (!chip->shutdown && !chip->probing)
622                 err = usb_autopm_get_interface(chip->pm_intf);
623
624         return err;
625 }
626
627 void snd_usb_autosuspend(struct snd_usb_audio *chip)
628 {
629         if (!chip->shutdown && !chip->probing)
630                 usb_autopm_put_interface(chip->pm_intf);
631 }
632
633 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
634 {
635         struct snd_usb_audio *chip = usb_get_intfdata(intf);
636         struct list_head *p;
637         struct snd_usb_stream *as;
638         struct usb_mixer_interface *mixer;
639
640         if (chip == (void *)-1L)
641                 return 0;
642
643         if (!PMSG_IS_AUTO(message)) {
644                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
645                 if (!chip->num_suspended_intf++) {
646                         list_for_each(p, &chip->pcm_list) {
647                                 as = list_entry(p, struct snd_usb_stream, list);
648                                 snd_pcm_suspend_all(as->pcm);
649                         }
650                 }
651         } else {
652                 /*
653                  * otherwise we keep the rest of the system in the dark
654                  * to keep this transparent
655                  */
656                 if (!chip->num_suspended_intf++)
657                         chip->autosuspended = 1;
658         }
659
660         list_for_each_entry(mixer, &chip->mixer_list, list)
661                 snd_usb_mixer_inactivate(mixer);
662
663         return 0;
664 }
665
666 static int usb_audio_resume(struct usb_interface *intf)
667 {
668         struct snd_usb_audio *chip = usb_get_intfdata(intf);
669         struct usb_mixer_interface *mixer;
670         int err = 0;
671
672         if (chip == (void *)-1L)
673                 return 0;
674         if (--chip->num_suspended_intf)
675                 return 0;
676         /*
677          * ALSA leaves material resumption to user space
678          * we just notify and restart the mixers
679          */
680         list_for_each_entry(mixer, &chip->mixer_list, list) {
681                 err = snd_usb_mixer_activate(mixer);
682                 if (err < 0)
683                         goto err_out;
684         }
685
686         if (!chip->autosuspended)
687                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
688         chip->autosuspended = 0;
689
690 err_out:
691         return err;
692 }
693 #else
694 #define usb_audio_suspend       NULL
695 #define usb_audio_resume        NULL
696 #endif          /* CONFIG_PM */
697
698 static struct usb_device_id usb_audio_ids [] = {
699 #include "quirks-table.h"
700     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
701       .bInterfaceClass = USB_CLASS_AUDIO,
702       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
703     { }                                         /* Terminating entry */
704 };
705
706 MODULE_DEVICE_TABLE (usb, usb_audio_ids);
707
708 /*
709  * entry point for linux usb interface
710  */
711
712 static struct usb_driver usb_audio_driver = {
713         .name =         "snd-usb-audio",
714         .probe =        usb_audio_probe,
715         .disconnect =   usb_audio_disconnect,
716         .suspend =      usb_audio_suspend,
717         .resume =       usb_audio_resume,
718         .id_table =     usb_audio_ids,
719         .supports_autosuspend = 1,
720 };
721
722 static int __init snd_usb_audio_init(void)
723 {
724         if (nrpacks < 1 || nrpacks > MAX_PACKS) {
725                 printk(KERN_WARNING "invalid nrpacks value.\n");
726                 return -EINVAL;
727         }
728         return usb_register(&usb_audio_driver);
729 }
730
731 static void __exit snd_usb_audio_cleanup(void)
732 {
733         usb_deregister(&usb_audio_driver);
734 }
735
736 module_init(snd_usb_audio_init);
737 module_exit(snd_usb_audio_cleanup);