Revert "ipv6: grab rt->rt6i_ref before allocating pcpu rt"
[linux/fpc-iii.git] / sound / usb / card.c
blob23d1d23aefec375c2c857f090f4920894e4bc7f8
1 /*
2 * (Tentative) USB Audio Driver for ALSA
4 * Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
6 * Many codes borrowed from audio.c by
7 * Alan Cox (alan@lxorguk.ukuu.org.uk)
8 * Thomas Sailer (sailer@ife.ee.ethz.ch)
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.
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.
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
26 * NOTES:
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).
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>
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>
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"
70 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
71 MODULE_DESCRIPTION("USB Audio");
72 MODULE_LICENSE("GPL");
73 MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
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];
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.");
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.
112 static DEFINE_MUTEX(register_mutex);
113 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
114 static struct usb_driver usb_audio_driver;
117 * disconnect streams
118 * called from usb_audio_disconnect()
120 static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
122 int idx;
123 struct snd_usb_substream *subs;
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;
135 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
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);
142 if (!iface) {
143 dev_err(&dev->dev, "%u:%d : does not exist\n",
144 ctrlif, interface);
145 return -EINVAL;
148 alts = &iface->altsetting[0];
149 altsd = get_iface_desc(alts);
152 * Android with both accessory and audio interfaces enabled gets the
153 * interface numbers wrong.
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);
168 if (usb_interface_claimed(iface)) {
169 dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
170 ctrlif, interface);
171 return -EINVAL;
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;
186 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
188 return 0;
191 if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
192 altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
193 altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
194 dev_dbg(&dev->dev,
195 "%u:%d: skipping non-supported interface %d\n",
196 ctrlif, interface, altsd->bInterfaceClass);
197 /* skip non-supported classes */
198 return -EINVAL;
201 if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
202 dev_err(&dev->dev, "low speed audio streaming not supported\n");
203 return -EINVAL;
206 if (! snd_usb_parse_audio_interface(chip, interface)) {
207 usb_set_interface(dev, interface, 0); /* reset the current interface */
208 usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
211 return 0;
215 * parse audio control descriptor and create pcm/midi streams
217 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
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;
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;
234 if (!control_header) {
235 dev_err(&dev->dev, "cannot find UAC_HEADER\n");
236 return -EINVAL;
239 rest_bytes = (void *)(host_iface->extra + host_iface->extralen) -
240 control_header;
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;
248 switch (protocol) {
249 default:
250 dev_warn(&dev->dev,
251 "unknown interface protocol %#02x, assuming v1\n",
252 protocol);
253 /* fall through */
255 case UAC_VERSION_1: {
256 struct uac1_ac_header_descriptor *h1 = control_header;
258 if (rest_bytes < sizeof(*h1)) {
259 dev_err(&dev->dev, "too short v1 buffer descriptor\n");
260 return -EINVAL;
263 if (!h1->bInCollection) {
264 dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
265 return -EINVAL;
268 if (rest_bytes < h1->bLength) {
269 dev_err(&dev->dev, "invalid buffer length (v1)\n");
270 return -EINVAL;
273 if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
274 dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
275 return -EINVAL;
278 for (i = 0; i < h1->bInCollection; i++)
279 snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
281 break;
284 case UAC_VERSION_2: {
285 struct usb_interface_assoc_descriptor *assoc =
286 usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
288 if (!assoc) {
290 * Firmware writers cannot count to three. So to find
291 * the IAD on the NuForce UDH-100, also check the next
292 * interface.
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;
303 if (!assoc) {
304 dev_err(&dev->dev, "Audio class v2 interfaces need an interface association\n");
305 return -EINVAL;
308 for (i = 0; i < assoc->bInterfaceCount; i++) {
309 int intf = assoc->bFirstInterface + i;
311 if (intf != ctrlif)
312 snd_usb_create_stream(chip, ctrlif, intf);
315 break;
319 return 0;
323 * free the chip instance
325 * here we have to do not much, since pcm and controls are already freed
329 static int snd_usb_audio_free(struct snd_usb_audio *chip)
331 struct snd_usb_endpoint *ep, *n;
333 list_for_each_entry_safe(ep, n, &chip->ep_list, list)
334 snd_usb_endpoint_free(ep);
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;
343 static int snd_usb_audio_dev_free(struct snd_device *device)
345 struct snd_usb_audio *chip = device->device_data;
346 return snd_usb_audio_free(chip);
350 * create a chip instance and set its names.
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 unsigned int usb_id,
356 struct snd_usb_audio **rchip)
358 struct snd_card *card;
359 struct snd_usb_audio *chip;
360 int err, len;
361 char component[14];
362 static struct snd_device_ops ops = {
363 .dev_free = snd_usb_audio_dev_free,
366 *rchip = NULL;
368 switch (snd_usb_get_speed(dev)) {
369 case USB_SPEED_LOW:
370 case USB_SPEED_FULL:
371 case USB_SPEED_HIGH:
372 case USB_SPEED_WIRELESS:
373 case USB_SPEED_SUPER:
374 case USB_SPEED_SUPER_PLUS:
375 break;
376 default:
377 dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
378 return -ENXIO;
381 err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
382 0, &card);
383 if (err < 0) {
384 dev_err(&dev->dev, "cannot create card instance %d\n", idx);
385 return err;
388 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
389 if (! chip) {
390 snd_card_free(card);
391 return -ENOMEM;
394 mutex_init(&chip->mutex);
395 init_waitqueue_head(&chip->shutdown_wait);
396 chip->index = idx;
397 chip->dev = dev;
398 chip->card = card;
399 chip->setup = device_setup[idx];
400 chip->autoclock = autoclock;
401 atomic_set(&chip->active, 1); /* avoid autopm during probing */
402 atomic_set(&chip->usage_count, 0);
403 atomic_set(&chip->shutdown, 0);
405 chip->usb_id = usb_id;
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);
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;
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);
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));
435 strim(card->shortname);
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 */
448 if (len > 0) {
449 strim(card->longname);
450 if (*card->longname)
451 strlcat(card->longname, " ", sizeof(card->longname));
454 strlcat(card->longname, card->shortname, sizeof(card->longname));
456 len = strlcat(card->longname, " at ", sizeof(card->longname));
458 if (len < sizeof(card->longname))
459 usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
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;
481 snd_usb_audio_create_proc(chip);
483 *rchip = chip;
484 return 0;
487 /* look for a matching quirk alias id */
488 static bool get_alias_id(struct usb_device *dev, unsigned int *id)
490 int i;
491 unsigned int src, dst;
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;
506 return false;
509 static const struct usb_device_id usb_audio_ids[]; /* defined below */
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)
515 const struct usb_device_id *p;
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;
526 return NULL;
530 * probe the active usb device
532 * note that this can be called multiple times per a device, when it
533 * includes multiple audio control interfaces.
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.
539 static int usb_audio_probe(struct usb_interface *intf,
540 const struct usb_device_id *usb_id)
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;
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;
560 err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
561 if (err < 0)
562 return err;
565 * found a config. now register to ALSA
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;
578 chip = usb_chip[i];
579 atomic_inc(&chip->active); /* avoid autopm */
580 break;
583 if (! chip) {
584 /* it's a fresh one.
585 * now look for an empty slot and create a new card instance
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 id, &chip);
593 if (err < 0)
594 goto __error;
595 chip->pm_intf = intf;
596 break;
598 if (!chip) {
599 dev_err(&dev->dev, "no available usb audio device\n");
600 err = -ENODEV;
601 goto __error;
604 dev_set_drvdata(&dev->dev, chip);
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.
611 if (!chip->ctrl_intf)
612 chip->ctrl_intf = alts;
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;
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;
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;
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;
645 __error:
646 if (chip) {
647 if (!chip->num_interfaces)
648 snd_card_free(chip->card);
649 atomic_dec(&chip->active);
651 mutex_unlock(&register_mutex);
652 return err;
656 * we need to take care of counter, since disconnection can be called also
657 * many times as well as usb_audio_probe().
659 static void usb_audio_disconnect(struct usb_interface *intf)
661 struct snd_usb_audio *chip = usb_get_intfdata(intf);
662 struct snd_card *card;
663 struct list_head *p;
665 if (chip == (void *)-1L)
666 return;
668 card = chip->card;
670 mutex_lock(&register_mutex);
671 if (atomic_inc_return(&chip->shutdown) == 1) {
672 struct snd_usb_stream *as;
673 struct snd_usb_endpoint *ep;
674 struct usb_mixer_interface *mixer;
676 /* wait until all pending tasks done;
677 * they are protected by snd_usb_lock_shutdown()
679 wait_event(chip->shutdown_wait,
680 !atomic_read(&chip->usage_count));
681 snd_card_disconnect(card);
682 /* release the pcm resources */
683 list_for_each_entry(as, &chip->pcm_list, list) {
684 snd_usb_stream_disconnect(as);
686 /* release the endpoint resources */
687 list_for_each_entry(ep, &chip->ep_list, list) {
688 snd_usb_endpoint_release(ep);
690 /* release the midi resources */
691 list_for_each(p, &chip->midi_list) {
692 snd_usbmidi_disconnect(p);
694 /* release mixer resources */
695 list_for_each_entry(mixer, &chip->mixer_list, list) {
696 snd_usb_mixer_disconnect(mixer);
700 chip->num_interfaces--;
701 if (chip->num_interfaces <= 0) {
702 usb_chip[chip->index] = NULL;
703 mutex_unlock(&register_mutex);
704 snd_card_free_when_closed(card);
705 } else {
706 mutex_unlock(&register_mutex);
710 /* lock the shutdown (disconnect) task and autoresume */
711 int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
713 int err;
715 atomic_inc(&chip->usage_count);
716 if (atomic_read(&chip->shutdown)) {
717 err = -EIO;
718 goto error;
720 err = snd_usb_autoresume(chip);
721 if (err < 0)
722 goto error;
723 return 0;
725 error:
726 if (atomic_dec_and_test(&chip->usage_count))
727 wake_up(&chip->shutdown_wait);
728 return err;
731 /* autosuspend and unlock the shutdown */
732 void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
734 snd_usb_autosuspend(chip);
735 if (atomic_dec_and_test(&chip->usage_count))
736 wake_up(&chip->shutdown_wait);
739 #ifdef CONFIG_PM
741 int snd_usb_autoresume(struct snd_usb_audio *chip)
743 if (atomic_read(&chip->shutdown))
744 return -EIO;
745 if (atomic_inc_return(&chip->active) == 1)
746 return usb_autopm_get_interface(chip->pm_intf);
747 return 0;
750 void snd_usb_autosuspend(struct snd_usb_audio *chip)
752 if (atomic_read(&chip->shutdown))
753 return;
754 if (atomic_dec_and_test(&chip->active))
755 usb_autopm_put_interface(chip->pm_intf);
758 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
760 struct snd_usb_audio *chip = usb_get_intfdata(intf);
761 struct snd_usb_stream *as;
762 struct usb_mixer_interface *mixer;
763 struct list_head *p;
765 if (chip == (void *)-1L)
766 return 0;
768 chip->autosuspended = !!PMSG_IS_AUTO(message);
769 if (!chip->autosuspended)
770 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
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;
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);
783 return 0;
786 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
788 struct snd_usb_audio *chip = usb_get_intfdata(intf);
789 struct usb_mixer_interface *mixer;
790 struct list_head *p;
791 int err = 0;
793 if (chip == (void *)-1L)
794 return 0;
795 if (--chip->num_suspended_intf)
796 return 0;
798 atomic_inc(&chip->active); /* avoid autopm */
800 * ALSA leaves material resumption to user space
801 * we just notify and restart the mixers
803 list_for_each_entry(mixer, &chip->mixer_list, list) {
804 err = snd_usb_mixer_resume(mixer, reset_resume);
805 if (err < 0)
806 goto err_out;
809 list_for_each(p, &chip->midi_list) {
810 snd_usbmidi_resume(p);
813 if (!chip->autosuspended)
814 snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
815 chip->autosuspended = 0;
817 err_out:
818 atomic_dec(&chip->active); /* allow autopm after this point */
819 return err;
822 static int usb_audio_resume(struct usb_interface *intf)
824 return __usb_audio_resume(intf, false);
827 static int usb_audio_reset_resume(struct usb_interface *intf)
829 return __usb_audio_resume(intf, true);
831 #else
832 #define usb_audio_suspend NULL
833 #define usb_audio_resume NULL
834 #define usb_audio_reset_resume NULL
835 #endif /* CONFIG_PM */
837 static const struct usb_device_id usb_audio_ids [] = {
838 #include "quirks-table.h"
839 { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
840 .bInterfaceClass = USB_CLASS_AUDIO,
841 .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
842 { } /* Terminating entry */
844 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
847 * entry point for linux usb interface
850 static struct usb_driver usb_audio_driver = {
851 .name = "snd-usb-audio",
852 .probe = usb_audio_probe,
853 .disconnect = usb_audio_disconnect,
854 .suspend = usb_audio_suspend,
855 .resume = usb_audio_resume,
856 .reset_resume = usb_audio_reset_resume,
857 .id_table = usb_audio_ids,
858 .supports_autosuspend = 1,
861 module_usb_driver(usb_audio_driver);