GNU Linux-libre 4.9.331-gnu1
[releases.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  *   - 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 static char *quirk_alias[SNDRV_CARDS];
86
87 module_param_array(index, int, NULL, 0444);
88 MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
89 module_param_array(id, charp, NULL, 0444);
90 MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
91 module_param_array(enable, bool, NULL, 0444);
92 MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
93 module_param_array(vid, int, NULL, 0444);
94 MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
95 module_param_array(pid, int, NULL, 0444);
96 MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
97 module_param_array(device_setup, int, NULL, 0444);
98 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
99 module_param(ignore_ctl_error, bool, 0444);
100 MODULE_PARM_DESC(ignore_ctl_error,
101                  "Ignore errors from USB controller for mixer interfaces.");
102 module_param(autoclock, bool, 0444);
103 MODULE_PARM_DESC(autoclock, "Enable auto-clock selection for UAC2 devices (default: yes).");
104 module_param_array(quirk_alias, charp, NULL, 0444);
105 MODULE_PARM_DESC(quirk_alias, "Quirk aliases, e.g. 0123abcd:5678beef.");
106
107 /*
108  * we keep the snd_usb_audio_t instances by ourselves for merging
109  * the all interfaces on the same card as one sound device.
110  */
111
112 static DEFINE_MUTEX(register_mutex);
113 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
114 static struct usb_driver usb_audio_driver;
115
116 /*
117  * disconnect streams
118  * called from usb_audio_disconnect()
119  */
120 static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
121 {
122         int idx;
123         struct snd_usb_substream *subs;
124
125         for (idx = 0; idx < 2; idx++) {
126                 subs = &as->substream[idx];
127                 if (!subs->num_formats)
128                         continue;
129                 subs->interface = -1;
130                 subs->data_endpoint = NULL;
131                 subs->sync_endpoint = NULL;
132         }
133 }
134
135 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
136 {
137         struct usb_device *dev = chip->dev;
138         struct usb_host_interface *alts;
139         struct usb_interface_descriptor *altsd;
140         struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
141
142         if (!iface) {
143                 dev_err(&dev->dev, "%u:%d : does not exist\n",
144                         ctrlif, interface);
145                 return -EINVAL;
146         }
147
148         alts = &iface->altsetting[0];
149         altsd = get_iface_desc(alts);
150
151         /*
152          * Android with both accessory and audio interfaces enabled gets the
153          * interface numbers wrong.
154          */
155         if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
156              chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
157             interface == 0 &&
158             altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
159             altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
160                 interface = 2;
161                 iface = usb_ifnum_to_if(dev, interface);
162                 if (!iface)
163                         return -EINVAL;
164                 alts = &iface->altsetting[0];
165                 altsd = get_iface_desc(alts);
166         }
167
168         if (usb_interface_claimed(iface)) {
169                 dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
170                         ctrlif, interface);
171                 return -EINVAL;
172         }
173
174         if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
175              altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
176             altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
177                 int err = __snd_usbmidi_create(chip->card, iface,
178                                              &chip->midi_list, NULL,
179                                              chip->usb_id);
180                 if (err < 0) {
181                         dev_err(&dev->dev,
182                                 "%u:%d: cannot create sequencer device\n",
183                                 ctrlif, interface);
184                         return -EINVAL;
185                 }
186                 return usb_driver_claim_interface(&usb_audio_driver, iface,
187                                                   USB_AUDIO_IFACE_UNUSED);
188         }
189
190         if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
191              altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
192             altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
193                 dev_dbg(&dev->dev,
194                         "%u:%d: skipping non-supported interface %d\n",
195                         ctrlif, interface, altsd->bInterfaceClass);
196                 /* skip non-supported classes */
197                 return -EINVAL;
198         }
199
200         if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
201                 dev_err(&dev->dev, "low speed audio streaming not supported\n");
202                 return -EINVAL;
203         }
204
205         if (! snd_usb_parse_audio_interface(chip, interface)) {
206                 usb_set_interface(dev, interface, 0); /* reset the current interface */
207                 return usb_driver_claim_interface(&usb_audio_driver, iface,
208                                                   USB_AUDIO_IFACE_UNUSED);
209         }
210
211         return 0;
212 }
213
214 /*
215  * parse audio control descriptor and create pcm/midi streams
216  */
217 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
218 {
219         struct usb_device *dev = chip->dev;
220         struct usb_host_interface *host_iface;
221         struct usb_interface_descriptor *altsd;
222         void *control_header;
223         int i, protocol;
224         int rest_bytes;
225
226         /* find audiocontrol interface */
227         host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
228         control_header = snd_usb_find_csint_desc(host_iface->extra,
229                                                  host_iface->extralen,
230                                                  NULL, UAC_HEADER);
231         altsd = get_iface_desc(host_iface);
232         protocol = altsd->bInterfaceProtocol;
233
234         if (!control_header) {
235                 dev_err(&dev->dev, "cannot find UAC_HEADER\n");
236                 return -EINVAL;
237         }
238
239         rest_bytes = (void *)(host_iface->extra + host_iface->extralen) -
240                 control_header;
241
242         /* just to be sure -- this shouldn't hit at all */
243         if (rest_bytes <= 0) {
244                 dev_err(&dev->dev, "invalid control header\n");
245                 return -EINVAL;
246         }
247
248         switch (protocol) {
249         default:
250                 dev_warn(&dev->dev,
251                          "unknown interface protocol %#02x, assuming v1\n",
252                          protocol);
253                 /* fall through */
254
255         case UAC_VERSION_1: {
256                 struct uac1_ac_header_descriptor *h1 = control_header;
257
258                 if (rest_bytes < sizeof(*h1)) {
259                         dev_err(&dev->dev, "too short v1 buffer descriptor\n");
260                         return -EINVAL;
261                 }
262
263                 if (!h1->bInCollection) {
264                         dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
265                         return -EINVAL;
266                 }
267
268                 if (rest_bytes < h1->bLength) {
269                         dev_err(&dev->dev, "invalid buffer length (v1)\n");
270                         return -EINVAL;
271                 }
272
273                 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
274                         dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
275                         return -EINVAL;
276                 }
277
278                 for (i = 0; i < h1->bInCollection; i++)
279                         snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
280
281                 break;
282         }
283
284         case UAC_VERSION_2: {
285                 struct usb_interface_assoc_descriptor *assoc =
286                         usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
287
288                 if (!assoc) {
289                         /*
290                          * Firmware writers cannot count to three.  So to find
291                          * the IAD on the NuForce UDH-100, also check the next
292                          * interface.
293                          */
294                         struct usb_interface *iface =
295                                 usb_ifnum_to_if(dev, ctrlif + 1);
296                         if (iface &&
297                             iface->intf_assoc &&
298                             iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
299                             iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
300                                 assoc = iface->intf_assoc;
301                 }
302
303                 if (!assoc) {
304                         dev_err(&dev->dev, "Audio class v2 interfaces need an interface association\n");
305                         return -EINVAL;
306                 }
307
308                 for (i = 0; i < assoc->bInterfaceCount; i++) {
309                         int intf = assoc->bFirstInterface + i;
310
311                         if (intf != ctrlif)
312                                 snd_usb_create_stream(chip, ctrlif, intf);
313                 }
314
315                 break;
316         }
317         }
318
319         return 0;
320 }
321
322 /*
323  * free the chip instance
324  *
325  * here we have to do not much, since pcm and controls are already freed
326  *
327  */
328
329 static int snd_usb_audio_free(struct snd_usb_audio *chip)
330 {
331         struct snd_usb_endpoint *ep, *n;
332
333         list_for_each_entry_safe(ep, n, &chip->ep_list, list)
334                 snd_usb_endpoint_free(ep);
335
336         mutex_destroy(&chip->mutex);
337         if (!atomic_read(&chip->shutdown))
338                 dev_set_drvdata(&chip->dev->dev, NULL);
339         kfree(chip);
340         return 0;
341 }
342
343 static int snd_usb_audio_dev_free(struct snd_device *device)
344 {
345         struct snd_usb_audio *chip = device->device_data;
346         return snd_usb_audio_free(chip);
347 }
348
349 /*
350  * create a chip instance and set its names.
351  */
352 static int snd_usb_audio_create(struct usb_interface *intf,
353                                 struct usb_device *dev, int idx,
354                                 const struct snd_usb_audio_quirk *quirk,
355                                 struct snd_usb_audio **rchip)
356 {
357         struct snd_card *card;
358         struct snd_usb_audio *chip;
359         int err, len;
360         char component[14];
361         static struct snd_device_ops ops = {
362                 .dev_free =     snd_usb_audio_dev_free,
363         };
364
365         *rchip = NULL;
366
367         switch (snd_usb_get_speed(dev)) {
368         case USB_SPEED_LOW:
369         case USB_SPEED_FULL:
370         case USB_SPEED_HIGH:
371         case USB_SPEED_WIRELESS:
372         case USB_SPEED_SUPER:
373         case USB_SPEED_SUPER_PLUS:
374                 break;
375         default:
376                 dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
377                 return -ENXIO;
378         }
379
380         err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
381                            0, &card);
382         if (err < 0) {
383                 dev_err(&dev->dev, "cannot create card instance %d\n", idx);
384                 return err;
385         }
386
387         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
388         if (! chip) {
389                 snd_card_free(card);
390                 return -ENOMEM;
391         }
392
393         mutex_init(&chip->mutex);
394         init_waitqueue_head(&chip->shutdown_wait);
395         chip->index = idx;
396         chip->dev = dev;
397         chip->card = card;
398         chip->setup = device_setup[idx];
399         chip->autoclock = autoclock;
400         atomic_set(&chip->active, 1); /* avoid autopm during probing */
401         atomic_set(&chip->usage_count, 0);
402         atomic_set(&chip->shutdown, 0);
403
404         chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
405                               le16_to_cpu(dev->descriptor.idProduct));
406         INIT_LIST_HEAD(&chip->pcm_list);
407         INIT_LIST_HEAD(&chip->ep_list);
408         INIT_LIST_HEAD(&chip->midi_list);
409         INIT_LIST_HEAD(&chip->mixer_list);
410
411         if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
412                 snd_usb_audio_free(chip);
413                 snd_card_free(card);
414                 return err;
415         }
416
417         strcpy(card->driver, "USB-Audio");
418         sprintf(component, "USB%04x:%04x",
419                 USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
420         snd_component_add(card, component);
421
422         /* retrieve the device string as shortname */
423         if (quirk && quirk->product_name && *quirk->product_name) {
424                 strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
425         } else {
426                 if (!dev->descriptor.iProduct ||
427                     usb_string(dev, dev->descriptor.iProduct,
428                     card->shortname, sizeof(card->shortname)) <= 0) {
429                         /* no name available from anywhere, so use ID */
430                         sprintf(card->shortname, "USB Device %#04x:%#04x",
431                                 USB_ID_VENDOR(chip->usb_id),
432                                 USB_ID_PRODUCT(chip->usb_id));
433                 }
434         }
435         strim(card->shortname);
436
437         /* retrieve the vendor and device strings as longname */
438         if (quirk && quirk->vendor_name && *quirk->vendor_name) {
439                 len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
440         } else {
441                 if (dev->descriptor.iManufacturer)
442                         len = usb_string(dev, dev->descriptor.iManufacturer,
443                                          card->longname, sizeof(card->longname));
444                 else
445                         len = 0;
446                 /* we don't really care if there isn't any vendor string */
447         }
448         if (len > 0) {
449                 strim(card->longname);
450                 if (*card->longname)
451                         strlcat(card->longname, " ", sizeof(card->longname));
452         }
453
454         strlcat(card->longname, card->shortname, sizeof(card->longname));
455
456         len = strlcat(card->longname, " at ", sizeof(card->longname));
457
458         if (len < sizeof(card->longname))
459                 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
460
461         switch (snd_usb_get_speed(dev)) {
462         case USB_SPEED_LOW:
463                 strlcat(card->longname, ", low speed", sizeof(card->longname));
464                 break;
465         case USB_SPEED_FULL:
466                 strlcat(card->longname, ", full speed", sizeof(card->longname));
467                 break;
468         case USB_SPEED_HIGH:
469                 strlcat(card->longname, ", high speed", sizeof(card->longname));
470                 break;
471         case USB_SPEED_SUPER:
472                 strlcat(card->longname, ", super speed", sizeof(card->longname));
473                 break;
474         case USB_SPEED_SUPER_PLUS:
475                 strlcat(card->longname, ", super speed plus", sizeof(card->longname));
476                 break;
477         default:
478                 break;
479         }
480
481         snd_usb_audio_create_proc(chip);
482
483         *rchip = chip;
484         return 0;
485 }
486
487 /* look for a matching quirk alias id */
488 static bool get_alias_id(struct usb_device *dev, unsigned int *id)
489 {
490         int i;
491         unsigned int src, dst;
492
493         for (i = 0; i < ARRAY_SIZE(quirk_alias); i++) {
494                 if (!quirk_alias[i] ||
495                     sscanf(quirk_alias[i], "%x:%x", &src, &dst) != 2 ||
496                     src != *id)
497                         continue;
498                 dev_info(&dev->dev,
499                          "device (%04x:%04x): applying quirk alias %04x:%04x\n",
500                          USB_ID_VENDOR(*id), USB_ID_PRODUCT(*id),
501                          USB_ID_VENDOR(dst), USB_ID_PRODUCT(dst));
502                 *id = dst;
503                 return true;
504         }
505
506         return false;
507 }
508
509 static struct usb_device_id usb_audio_ids[]; /* defined below */
510
511 /* look for the corresponding quirk */
512 static const struct snd_usb_audio_quirk *
513 get_alias_quirk(struct usb_device *dev, unsigned int id)
514 {
515         const struct usb_device_id *p;
516
517         for (p = usb_audio_ids; p->match_flags; p++) {
518                 /* FIXME: this checks only vendor:product pair in the list */
519                 if ((p->match_flags & USB_DEVICE_ID_MATCH_DEVICE) ==
520                     USB_DEVICE_ID_MATCH_DEVICE &&
521                     p->idVendor == USB_ID_VENDOR(id) &&
522                     p->idProduct == USB_ID_PRODUCT(id))
523                         return (const struct snd_usb_audio_quirk *)p->driver_info;
524         }
525
526         return NULL;
527 }
528
529 /*
530  * probe the active usb device
531  *
532  * note that this can be called multiple times per a device, when it
533  * includes multiple audio control interfaces.
534  *
535  * thus we check the usb device pointer and creates the card instance
536  * only at the first time.  the successive calls of this function will
537  * append the pcm interface to the corresponding card.
538  */
539 static int usb_audio_probe(struct usb_interface *intf,
540                            const struct usb_device_id *usb_id)
541 {
542         struct usb_device *dev = interface_to_usbdev(intf);
543         const struct snd_usb_audio_quirk *quirk =
544                 (const struct snd_usb_audio_quirk *)usb_id->driver_info;
545         struct snd_usb_audio *chip;
546         int i, err;
547         struct usb_host_interface *alts;
548         int ifnum;
549         u32 id;
550
551         alts = &intf->altsetting[0];
552         ifnum = get_iface_desc(alts)->bInterfaceNumber;
553         id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
554                     le16_to_cpu(dev->descriptor.idProduct));
555         if (get_alias_id(dev, &id))
556                 quirk = get_alias_quirk(dev, id);
557         if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
558                 return -ENXIO;
559
560         err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
561         if (err < 0)
562                 return err;
563
564         /*
565          * found a config.  now register to ALSA
566          */
567
568         /* check whether it's already registered */
569         chip = NULL;
570         mutex_lock(&register_mutex);
571         for (i = 0; i < SNDRV_CARDS; i++) {
572                 if (usb_chip[i] && usb_chip[i]->dev == dev) {
573                         if (atomic_read(&usb_chip[i]->shutdown)) {
574                                 dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
575                                 err = -EIO;
576                                 goto __error;
577                         }
578                         chip = usb_chip[i];
579                         atomic_inc(&chip->active); /* avoid autopm */
580                         break;
581                 }
582         }
583         if (! chip) {
584                 /* it's a fresh one.
585                  * now look for an empty slot and create a new card instance
586                  */
587                 for (i = 0; i < SNDRV_CARDS; i++)
588                         if (enable[i] && ! usb_chip[i] &&
589                             (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
590                             (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
591                                 err = snd_usb_audio_create(intf, dev, i, quirk,
592                                                            &chip);
593                                 if (err < 0)
594                                         goto __error;
595                                 chip->pm_intf = intf;
596                                 break;
597                         }
598                 if (!chip) {
599                         dev_err(&dev->dev, "no available usb audio device\n");
600                         err = -ENODEV;
601                         goto __error;
602                 }
603         }
604         dev_set_drvdata(&dev->dev, chip);
605
606         /*
607          * For devices with more than one control interface, we assume the
608          * first contains the audio controls. We might need a more specific
609          * check here in the future.
610          */
611         if (!chip->ctrl_intf)
612                 chip->ctrl_intf = alts;
613
614         chip->txfr_quirk = 0;
615         err = 1; /* continue */
616         if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
617                 /* need some special handlings */
618                 err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk);
619                 if (err < 0)
620                         goto __error;
621         }
622
623         if (err > 0) {
624                 /* create normal USB audio interfaces */
625                 err = snd_usb_create_streams(chip, ifnum);
626                 if (err < 0)
627                         goto __error;
628                 err = snd_usb_create_mixer(chip, ifnum, ignore_ctl_error);
629                 if (err < 0)
630                         goto __error;
631         }
632
633         /* we are allowed to call snd_card_register() many times */
634         err = snd_card_register(chip->card);
635         if (err < 0)
636                 goto __error;
637
638         usb_chip[chip->index] = chip;
639         chip->num_interfaces++;
640         usb_set_intfdata(intf, chip);
641         atomic_dec(&chip->active);
642         mutex_unlock(&register_mutex);
643         return 0;
644
645  __error:
646         if (chip) {
647                 /* chip->active is inside the chip->card object,
648                  * decrement before memory is possibly returned.
649                  */
650                 atomic_dec(&chip->active);
651                 if (!chip->num_interfaces)
652                         snd_card_free(chip->card);
653         }
654         mutex_unlock(&register_mutex);
655         return err;
656 }
657
658 /*
659  * we need to take care of counter, since disconnection can be called also
660  * many times as well as usb_audio_probe().
661  */
662 static void usb_audio_disconnect(struct usb_interface *intf)
663 {
664         struct snd_usb_audio *chip = usb_get_intfdata(intf);
665         struct snd_card *card;
666         struct list_head *p;
667
668         if (chip == USB_AUDIO_IFACE_UNUSED)
669                 return;
670
671         card = chip->card;
672
673         mutex_lock(&register_mutex);
674         if (atomic_inc_return(&chip->shutdown) == 1) {
675                 struct snd_usb_stream *as;
676                 struct snd_usb_endpoint *ep;
677                 struct usb_mixer_interface *mixer;
678
679                 /* wait until all pending tasks done;
680                  * they are protected by snd_usb_lock_shutdown()
681                  */
682                 wait_event(chip->shutdown_wait,
683                            !atomic_read(&chip->usage_count));
684                 snd_card_disconnect(card);
685                 /* release the pcm resources */
686                 list_for_each_entry(as, &chip->pcm_list, list) {
687                         snd_usb_stream_disconnect(as);
688                 }
689                 /* release the endpoint resources */
690                 list_for_each_entry(ep, &chip->ep_list, list) {
691                         snd_usb_endpoint_release(ep);
692                 }
693                 /* release the midi resources */
694                 list_for_each(p, &chip->midi_list) {
695                         snd_usbmidi_disconnect(p);
696                 }
697                 /* release mixer resources */
698                 list_for_each_entry(mixer, &chip->mixer_list, list) {
699                         snd_usb_mixer_disconnect(mixer);
700                 }
701         }
702
703         chip->num_interfaces--;
704         if (chip->num_interfaces <= 0) {
705                 usb_chip[chip->index] = NULL;
706                 mutex_unlock(&register_mutex);
707                 snd_card_free_when_closed(card);
708         } else {
709                 mutex_unlock(&register_mutex);
710         }
711 }
712
713 /* lock the shutdown (disconnect) task and autoresume */
714 int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
715 {
716         int err;
717
718         atomic_inc(&chip->usage_count);
719         if (atomic_read(&chip->shutdown)) {
720                 err = -EIO;
721                 goto error;
722         }
723         err = snd_usb_autoresume(chip);
724         if (err < 0)
725                 goto error;
726         return 0;
727
728  error:
729         if (atomic_dec_and_test(&chip->usage_count))
730                 wake_up(&chip->shutdown_wait);
731         return err;
732 }
733
734 /* autosuspend and unlock the shutdown */
735 void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
736 {
737         snd_usb_autosuspend(chip);
738         if (atomic_dec_and_test(&chip->usage_count))
739                 wake_up(&chip->shutdown_wait);
740 }
741
742 #ifdef CONFIG_PM
743
744 int snd_usb_autoresume(struct snd_usb_audio *chip)
745 {
746         if (atomic_read(&chip->shutdown))
747                 return -EIO;
748         if (atomic_inc_return(&chip->active) == 1)
749                 return usb_autopm_get_interface(chip->pm_intf);
750         return 0;
751 }
752
753 void snd_usb_autosuspend(struct snd_usb_audio *chip)
754 {
755         if (atomic_read(&chip->shutdown))
756                 return;
757         if (atomic_dec_and_test(&chip->active))
758                 usb_autopm_put_interface(chip->pm_intf);
759 }
760
761 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
762 {
763         struct snd_usb_audio *chip = usb_get_intfdata(intf);
764         struct snd_usb_stream *as;
765         struct usb_mixer_interface *mixer;
766         struct list_head *p;
767
768         if (chip == USB_AUDIO_IFACE_UNUSED)
769                 return 0;
770
771         if (!chip->num_suspended_intf++) {
772                 list_for_each_entry(as, &chip->pcm_list, list) {
773                         snd_pcm_suspend_all(as->pcm);
774                         as->substream[0].need_setup_ep =
775                                 as->substream[1].need_setup_ep = true;
776                 }
777                 list_for_each(p, &chip->midi_list)
778                         snd_usbmidi_suspend(p);
779                 list_for_each_entry(mixer, &chip->mixer_list, list)
780                         snd_usb_mixer_suspend(mixer);
781         }
782
783         if (!PMSG_IS_AUTO(message) && !chip->system_suspend) {
784                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
785                 chip->system_suspend = chip->num_suspended_intf;
786         }
787
788         return 0;
789 }
790
791 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
792 {
793         struct snd_usb_audio *chip = usb_get_intfdata(intf);
794         struct usb_mixer_interface *mixer;
795         struct list_head *p;
796         int err = 0;
797
798         if (chip == USB_AUDIO_IFACE_UNUSED)
799                 return 0;
800
801         atomic_inc(&chip->active); /* avoid autopm */
802         if (chip->num_suspended_intf > 1)
803                 goto out;
804
805         /*
806          * ALSA leaves material resumption to user space
807          * we just notify and restart the mixers
808          */
809         list_for_each_entry(mixer, &chip->mixer_list, list) {
810                 err = snd_usb_mixer_resume(mixer, reset_resume);
811                 if (err < 0)
812                         goto err_out;
813         }
814
815         list_for_each(p, &chip->midi_list) {
816                 snd_usbmidi_resume(p);
817         }
818
819  out:
820         if (chip->num_suspended_intf == chip->system_suspend) {
821                 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
822                 chip->system_suspend = 0;
823         }
824         chip->num_suspended_intf--;
825
826 err_out:
827         atomic_dec(&chip->active); /* allow autopm after this point */
828         return err;
829 }
830
831 static int usb_audio_resume(struct usb_interface *intf)
832 {
833         return __usb_audio_resume(intf, false);
834 }
835
836 static int usb_audio_reset_resume(struct usb_interface *intf)
837 {
838         return __usb_audio_resume(intf, true);
839 }
840 #else
841 #define usb_audio_suspend       NULL
842 #define usb_audio_resume        NULL
843 #define usb_audio_reset_resume  NULL
844 #endif          /* CONFIG_PM */
845
846 static struct usb_device_id usb_audio_ids [] = {
847 #include "quirks-table.h"
848     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
849       .bInterfaceClass = USB_CLASS_AUDIO,
850       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
851     { }                                         /* Terminating entry */
852 };
853 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
854
855 /*
856  * entry point for linux usb interface
857  */
858
859 static struct usb_driver usb_audio_driver = {
860         .name =         "snd-usb-audio",
861         .probe =        usb_audio_probe,
862         .disconnect =   usb_audio_disconnect,
863         .suspend =      usb_audio_suspend,
864         .resume =       usb_audio_resume,
865         .reset_resume = usb_audio_reset_resume,
866         .id_table =     usb_audio_ids,
867         .supports_autosuspend = 1,
868 };
869
870 module_usb_driver(usb_audio_driver);