xref: /openbmc/linux/sound/usb/card.c (revision 9fb29c73)
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  *   Audio Class 3.0 support by Ruslan Bilovol <ruslan.bilovol@gmail.com>
11  *
12  *   This program is free software; you can redistribute it and/or modify
13  *   it under the terms of the GNU General Public License as published by
14  *   the Free Software Foundation; either version 2 of the License, or
15  *   (at your option) any later version.
16  *
17  *   This program is distributed in the hope that it will be useful,
18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *   GNU General Public License for more details.
21  *
22  *   You should have received a copy of the GNU General Public License
23  *   along with this program; if not, write to the Free Software
24  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
25  *
26  *
27  *  NOTES:
28  *
29  *   - the linked URBs would be preferred but not used so far because of
30  *     the instability of unlinking.
31  *   - type II is not supported properly.  there is no device which supports
32  *     this type *correctly*.  SB extigy looks as if it supports, but it's
33  *     indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
34  */
35 
36 
37 #include <linux/bitops.h>
38 #include <linux/init.h>
39 #include <linux/list.h>
40 #include <linux/slab.h>
41 #include <linux/string.h>
42 #include <linux/ctype.h>
43 #include <linux/usb.h>
44 #include <linux/moduleparam.h>
45 #include <linux/mutex.h>
46 #include <linux/usb/audio.h>
47 #include <linux/usb/audio-v2.h>
48 #include <linux/usb/audio-v3.h>
49 #include <linux/module.h>
50 
51 #include <sound/control.h>
52 #include <sound/core.h>
53 #include <sound/info.h>
54 #include <sound/pcm.h>
55 #include <sound/pcm_params.h>
56 #include <sound/initval.h>
57 
58 #include "usbaudio.h"
59 #include "card.h"
60 #include "midi.h"
61 #include "mixer.h"
62 #include "proc.h"
63 #include "quirks.h"
64 #include "endpoint.h"
65 #include "helper.h"
66 #include "debug.h"
67 #include "pcm.h"
68 #include "format.h"
69 #include "power.h"
70 #include "stream.h"
71 
72 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
73 MODULE_DESCRIPTION("USB Audio");
74 MODULE_LICENSE("GPL");
75 MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");
76 
77 
78 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
79 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
80 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
81 /* Vendor/product IDs for this card */
82 static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
83 static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
84 static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
85 static bool ignore_ctl_error;
86 static bool autoclock = true;
87 static char *quirk_alias[SNDRV_CARDS];
88 
89 bool snd_usb_use_vmalloc = true;
90 
91 module_param_array(index, int, NULL, 0444);
92 MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
93 module_param_array(id, charp, NULL, 0444);
94 MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
95 module_param_array(enable, bool, NULL, 0444);
96 MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
97 module_param_array(vid, int, NULL, 0444);
98 MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
99 module_param_array(pid, int, NULL, 0444);
100 MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
101 module_param_array(device_setup, int, NULL, 0444);
102 MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
103 module_param(ignore_ctl_error, bool, 0444);
104 MODULE_PARM_DESC(ignore_ctl_error,
105 		 "Ignore errors from USB controller for mixer interfaces.");
106 module_param(autoclock, bool, 0444);
107 MODULE_PARM_DESC(autoclock, "Enable auto-clock selection for UAC2 devices (default: yes).");
108 module_param_array(quirk_alias, charp, NULL, 0444);
109 MODULE_PARM_DESC(quirk_alias, "Quirk aliases, e.g. 0123abcd:5678beef.");
110 module_param_named(use_vmalloc, snd_usb_use_vmalloc, bool, 0444);
111 MODULE_PARM_DESC(use_vmalloc, "Use vmalloc for PCM intermediate buffers (default: yes).");
112 
113 /*
114  * we keep the snd_usb_audio_t instances by ourselves for merging
115  * the all interfaces on the same card as one sound device.
116  */
117 
118 static DEFINE_MUTEX(register_mutex);
119 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
120 static struct usb_driver usb_audio_driver;
121 
122 /*
123  * disconnect streams
124  * called from usb_audio_disconnect()
125  */
126 static void snd_usb_stream_disconnect(struct snd_usb_stream *as)
127 {
128 	int idx;
129 	struct snd_usb_substream *subs;
130 
131 	for (idx = 0; idx < 2; idx++) {
132 		subs = &as->substream[idx];
133 		if (!subs->num_formats)
134 			continue;
135 		subs->interface = -1;
136 		subs->data_endpoint = NULL;
137 		subs->sync_endpoint = NULL;
138 	}
139 }
140 
141 static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
142 {
143 	struct usb_device *dev = chip->dev;
144 	struct usb_host_interface *alts;
145 	struct usb_interface_descriptor *altsd;
146 	struct usb_interface *iface = usb_ifnum_to_if(dev, interface);
147 
148 	if (!iface) {
149 		dev_err(&dev->dev, "%u:%d : does not exist\n",
150 			ctrlif, interface);
151 		return -EINVAL;
152 	}
153 
154 	alts = &iface->altsetting[0];
155 	altsd = get_iface_desc(alts);
156 
157 	/*
158 	 * Android with both accessory and audio interfaces enabled gets the
159 	 * interface numbers wrong.
160 	 */
161 	if ((chip->usb_id == USB_ID(0x18d1, 0x2d04) ||
162 	     chip->usb_id == USB_ID(0x18d1, 0x2d05)) &&
163 	    interface == 0 &&
164 	    altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC &&
165 	    altsd->bInterfaceSubClass == USB_SUBCLASS_VENDOR_SPEC) {
166 		interface = 2;
167 		iface = usb_ifnum_to_if(dev, interface);
168 		if (!iface)
169 			return -EINVAL;
170 		alts = &iface->altsetting[0];
171 		altsd = get_iface_desc(alts);
172 	}
173 
174 	if (usb_interface_claimed(iface)) {
175 		dev_dbg(&dev->dev, "%d:%d: skipping, already claimed\n",
176 			ctrlif, interface);
177 		return -EINVAL;
178 	}
179 
180 	if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
181 	     altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
182 	    altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
183 		int err = __snd_usbmidi_create(chip->card, iface,
184 					     &chip->midi_list, NULL,
185 					     chip->usb_id);
186 		if (err < 0) {
187 			dev_err(&dev->dev,
188 				"%u:%d: cannot create sequencer device\n",
189 				ctrlif, interface);
190 			return -EINVAL;
191 		}
192 		usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
193 
194 		return 0;
195 	}
196 
197 	if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
198 	     altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
199 	    altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
200 		dev_dbg(&dev->dev,
201 			"%u:%d: skipping non-supported interface %d\n",
202 			ctrlif, interface, altsd->bInterfaceClass);
203 		/* skip non-supported classes */
204 		return -EINVAL;
205 	}
206 
207 	if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
208 		dev_err(&dev->dev, "low speed audio streaming not supported\n");
209 		return -EINVAL;
210 	}
211 
212 	if (! snd_usb_parse_audio_interface(chip, interface)) {
213 		usb_set_interface(dev, interface, 0); /* reset the current interface */
214 		usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
215 	}
216 
217 	return 0;
218 }
219 
220 /*
221  * parse audio control descriptor and create pcm/midi streams
222  */
223 static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
224 {
225 	struct usb_device *dev = chip->dev;
226 	struct usb_host_interface *host_iface;
227 	struct usb_interface_descriptor *altsd;
228 	int i, protocol;
229 
230 	/* find audiocontrol interface */
231 	host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
232 	altsd = get_iface_desc(host_iface);
233 	protocol = altsd->bInterfaceProtocol;
234 
235 	switch (protocol) {
236 	default:
237 		dev_warn(&dev->dev,
238 			 "unknown interface protocol %#02x, assuming v1\n",
239 			 protocol);
240 		/* fall through */
241 
242 	case UAC_VERSION_1: {
243 		struct uac1_ac_header_descriptor *h1;
244 		int rest_bytes;
245 
246 		h1 = snd_usb_find_csint_desc(host_iface->extra,
247 							 host_iface->extralen,
248 							 NULL, UAC_HEADER);
249 		if (!h1 || h1->bLength < sizeof(*h1)) {
250 			dev_err(&dev->dev, "cannot find UAC_HEADER\n");
251 			return -EINVAL;
252 		}
253 
254 		rest_bytes = (void *)(host_iface->extra +
255 				host_iface->extralen) - (void *)h1;
256 
257 		/* just to be sure -- this shouldn't hit at all */
258 		if (rest_bytes <= 0) {
259 			dev_err(&dev->dev, "invalid control header\n");
260 			return -EINVAL;
261 		}
262 
263 		if (rest_bytes < sizeof(*h1)) {
264 			dev_err(&dev->dev, "too short v1 buffer descriptor\n");
265 			return -EINVAL;
266 		}
267 
268 		if (!h1->bInCollection) {
269 			dev_info(&dev->dev, "skipping empty audio interface (v1)\n");
270 			return -EINVAL;
271 		}
272 
273 		if (rest_bytes < h1->bLength) {
274 			dev_err(&dev->dev, "invalid buffer length (v1)\n");
275 			return -EINVAL;
276 		}
277 
278 		if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
279 			dev_err(&dev->dev, "invalid UAC_HEADER (v1)\n");
280 			return -EINVAL;
281 		}
282 
283 		for (i = 0; i < h1->bInCollection; i++)
284 			snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);
285 
286 		break;
287 	}
288 
289 	case UAC_VERSION_2:
290 	case UAC_VERSION_3: {
291 		struct usb_interface_assoc_descriptor *assoc =
292 			usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
293 
294 		if (!assoc) {
295 			/*
296 			 * Firmware writers cannot count to three.  So to find
297 			 * the IAD on the NuForce UDH-100, also check the next
298 			 * interface.
299 			 */
300 			struct usb_interface *iface =
301 				usb_ifnum_to_if(dev, ctrlif + 1);
302 			if (iface &&
303 			    iface->intf_assoc &&
304 			    iface->intf_assoc->bFunctionClass == USB_CLASS_AUDIO &&
305 			    iface->intf_assoc->bFunctionProtocol == UAC_VERSION_2)
306 				assoc = iface->intf_assoc;
307 		}
308 
309 		if (!assoc) {
310 			dev_err(&dev->dev, "Audio class v2/v3 interfaces need an interface association\n");
311 			return -EINVAL;
312 		}
313 
314 		if (protocol == UAC_VERSION_3) {
315 			int badd = assoc->bFunctionSubClass;
316 
317 			if (badd != UAC3_FUNCTION_SUBCLASS_FULL_ADC_3_0 &&
318 			    (badd < UAC3_FUNCTION_SUBCLASS_GENERIC_IO ||
319 			     badd > UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE)) {
320 				dev_err(&dev->dev,
321 					"Unsupported UAC3 BADD profile\n");
322 				return -EINVAL;
323 			}
324 
325 			chip->badd_profile = badd;
326 		}
327 
328 		for (i = 0; i < assoc->bInterfaceCount; i++) {
329 			int intf = assoc->bFirstInterface + i;
330 
331 			if (intf != ctrlif)
332 				snd_usb_create_stream(chip, ctrlif, intf);
333 		}
334 
335 		break;
336 	}
337 	}
338 
339 	return 0;
340 }
341 
342 /*
343  * free the chip instance
344  *
345  * here we have to do not much, since pcm and controls are already freed
346  *
347  */
348 
349 static void snd_usb_audio_free(struct snd_card *card)
350 {
351 	struct snd_usb_audio *chip = card->private_data;
352 	struct snd_usb_endpoint *ep, *n;
353 
354 	list_for_each_entry_safe(ep, n, &chip->ep_list, list)
355 		snd_usb_endpoint_free(ep);
356 
357 	mutex_destroy(&chip->mutex);
358 	if (!atomic_read(&chip->shutdown))
359 		dev_set_drvdata(&chip->dev->dev, NULL);
360 }
361 
362 static void usb_audio_make_shortname(struct usb_device *dev,
363 				     struct snd_usb_audio *chip,
364 				     const struct snd_usb_audio_quirk *quirk)
365 {
366 	struct snd_card *card = chip->card;
367 
368 	if (quirk && quirk->product_name && *quirk->product_name) {
369 		strlcpy(card->shortname, quirk->product_name,
370 			sizeof(card->shortname));
371 		return;
372 	}
373 
374 	/* retrieve the device string as shortname */
375 	if (!dev->descriptor.iProduct ||
376 	    usb_string(dev, dev->descriptor.iProduct,
377 		       card->shortname, sizeof(card->shortname)) <= 0) {
378 		/* no name available from anywhere, so use ID */
379 		sprintf(card->shortname, "USB Device %#04x:%#04x",
380 			USB_ID_VENDOR(chip->usb_id),
381 			USB_ID_PRODUCT(chip->usb_id));
382 	}
383 
384 	strim(card->shortname);
385 }
386 
387 static void usb_audio_make_longname(struct usb_device *dev,
388 				    struct snd_usb_audio *chip,
389 				    const struct snd_usb_audio_quirk *quirk)
390 {
391 	struct snd_card *card = chip->card;
392 	int len;
393 
394 	/* shortcut - if any pre-defined string is given, use it */
395 	if (quirk && quirk->profile_name && *quirk->profile_name) {
396 		strlcpy(card->longname, quirk->profile_name,
397 			sizeof(card->longname));
398 		return;
399 	}
400 
401 	if (quirk && quirk->vendor_name && *quirk->vendor_name) {
402 		len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
403 	} else {
404 		/* retrieve the vendor and device strings as longname */
405 		if (dev->descriptor.iManufacturer)
406 			len = usb_string(dev, dev->descriptor.iManufacturer,
407 					 card->longname, sizeof(card->longname));
408 		else
409 			len = 0;
410 		/* we don't really care if there isn't any vendor string */
411 	}
412 	if (len > 0) {
413 		strim(card->longname);
414 		if (*card->longname)
415 			strlcat(card->longname, " ", sizeof(card->longname));
416 	}
417 
418 	strlcat(card->longname, card->shortname, sizeof(card->longname));
419 
420 	len = strlcat(card->longname, " at ", sizeof(card->longname));
421 
422 	if (len < sizeof(card->longname))
423 		usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);
424 
425 	switch (snd_usb_get_speed(dev)) {
426 	case USB_SPEED_LOW:
427 		strlcat(card->longname, ", low speed", sizeof(card->longname));
428 		break;
429 	case USB_SPEED_FULL:
430 		strlcat(card->longname, ", full speed", sizeof(card->longname));
431 		break;
432 	case USB_SPEED_HIGH:
433 		strlcat(card->longname, ", high speed", sizeof(card->longname));
434 		break;
435 	case USB_SPEED_SUPER:
436 		strlcat(card->longname, ", super speed", sizeof(card->longname));
437 		break;
438 	case USB_SPEED_SUPER_PLUS:
439 		strlcat(card->longname, ", super speed plus", sizeof(card->longname));
440 		break;
441 	default:
442 		break;
443 	}
444 }
445 
446 /*
447  * create a chip instance and set its names.
448  */
449 static int snd_usb_audio_create(struct usb_interface *intf,
450 				struct usb_device *dev, int idx,
451 				const struct snd_usb_audio_quirk *quirk,
452 				unsigned int usb_id,
453 				struct snd_usb_audio **rchip)
454 {
455 	struct snd_card *card;
456 	struct snd_usb_audio *chip;
457 	int err;
458 	char component[14];
459 
460 	*rchip = NULL;
461 
462 	switch (snd_usb_get_speed(dev)) {
463 	case USB_SPEED_LOW:
464 	case USB_SPEED_FULL:
465 	case USB_SPEED_HIGH:
466 	case USB_SPEED_WIRELESS:
467 	case USB_SPEED_SUPER:
468 	case USB_SPEED_SUPER_PLUS:
469 		break;
470 	default:
471 		dev_err(&dev->dev, "unknown device speed %d\n", snd_usb_get_speed(dev));
472 		return -ENXIO;
473 	}
474 
475 	err = snd_card_new(&intf->dev, index[idx], id[idx], THIS_MODULE,
476 			   sizeof(*chip), &card);
477 	if (err < 0) {
478 		dev_err(&dev->dev, "cannot create card instance %d\n", idx);
479 		return err;
480 	}
481 
482 	chip = card->private_data;
483 	mutex_init(&chip->mutex);
484 	init_waitqueue_head(&chip->shutdown_wait);
485 	chip->index = idx;
486 	chip->dev = dev;
487 	chip->card = card;
488 	chip->setup = device_setup[idx];
489 	chip->autoclock = autoclock;
490 	atomic_set(&chip->active, 1); /* avoid autopm during probing */
491 	atomic_set(&chip->usage_count, 0);
492 	atomic_set(&chip->shutdown, 0);
493 
494 	chip->usb_id = usb_id;
495 	INIT_LIST_HEAD(&chip->pcm_list);
496 	INIT_LIST_HEAD(&chip->ep_list);
497 	INIT_LIST_HEAD(&chip->midi_list);
498 	INIT_LIST_HEAD(&chip->mixer_list);
499 
500 	card->private_free = snd_usb_audio_free;
501 
502 	strcpy(card->driver, "USB-Audio");
503 	sprintf(component, "USB%04x:%04x",
504 		USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
505 	snd_component_add(card, component);
506 
507 	usb_audio_make_shortname(dev, chip, quirk);
508 	usb_audio_make_longname(dev, chip, quirk);
509 
510 	snd_usb_audio_create_proc(chip);
511 
512 	*rchip = chip;
513 	return 0;
514 }
515 
516 /* look for a matching quirk alias id */
517 static bool get_alias_id(struct usb_device *dev, unsigned int *id)
518 {
519 	int i;
520 	unsigned int src, dst;
521 
522 	for (i = 0; i < ARRAY_SIZE(quirk_alias); i++) {
523 		if (!quirk_alias[i] ||
524 		    sscanf(quirk_alias[i], "%x:%x", &src, &dst) != 2 ||
525 		    src != *id)
526 			continue;
527 		dev_info(&dev->dev,
528 			 "device (%04x:%04x): applying quirk alias %04x:%04x\n",
529 			 USB_ID_VENDOR(*id), USB_ID_PRODUCT(*id),
530 			 USB_ID_VENDOR(dst), USB_ID_PRODUCT(dst));
531 		*id = dst;
532 		return true;
533 	}
534 
535 	return false;
536 }
537 
538 static const struct usb_device_id usb_audio_ids[]; /* defined below */
539 
540 /* look for the corresponding quirk */
541 static const struct snd_usb_audio_quirk *
542 get_alias_quirk(struct usb_device *dev, unsigned int id)
543 {
544 	const struct usb_device_id *p;
545 
546 	for (p = usb_audio_ids; p->match_flags; p++) {
547 		/* FIXME: this checks only vendor:product pair in the list */
548 		if ((p->match_flags & USB_DEVICE_ID_MATCH_DEVICE) ==
549 		    USB_DEVICE_ID_MATCH_DEVICE &&
550 		    p->idVendor == USB_ID_VENDOR(id) &&
551 		    p->idProduct == USB_ID_PRODUCT(id))
552 			return (const struct snd_usb_audio_quirk *)p->driver_info;
553 	}
554 
555 	return NULL;
556 }
557 
558 /*
559  * probe the active usb device
560  *
561  * note that this can be called multiple times per a device, when it
562  * includes multiple audio control interfaces.
563  *
564  * thus we check the usb device pointer and creates the card instance
565  * only at the first time.  the successive calls of this function will
566  * append the pcm interface to the corresponding card.
567  */
568 static int usb_audio_probe(struct usb_interface *intf,
569 			   const struct usb_device_id *usb_id)
570 {
571 	struct usb_device *dev = interface_to_usbdev(intf);
572 	const struct snd_usb_audio_quirk *quirk =
573 		(const struct snd_usb_audio_quirk *)usb_id->driver_info;
574 	struct snd_usb_audio *chip;
575 	int i, err;
576 	struct usb_host_interface *alts;
577 	int ifnum;
578 	u32 id;
579 
580 	alts = &intf->altsetting[0];
581 	ifnum = get_iface_desc(alts)->bInterfaceNumber;
582 	id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
583 		    le16_to_cpu(dev->descriptor.idProduct));
584 	if (get_alias_id(dev, &id))
585 		quirk = get_alias_quirk(dev, id);
586 	if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
587 		return -ENXIO;
588 
589 	err = snd_usb_apply_boot_quirk(dev, intf, quirk, id);
590 	if (err < 0)
591 		return err;
592 
593 	/*
594 	 * found a config.  now register to ALSA
595 	 */
596 
597 	/* check whether it's already registered */
598 	chip = NULL;
599 	mutex_lock(&register_mutex);
600 	for (i = 0; i < SNDRV_CARDS; i++) {
601 		if (usb_chip[i] && usb_chip[i]->dev == dev) {
602 			if (atomic_read(&usb_chip[i]->shutdown)) {
603 				dev_err(&dev->dev, "USB device is in the shutdown state, cannot create a card instance\n");
604 				err = -EIO;
605 				goto __error;
606 			}
607 			chip = usb_chip[i];
608 			atomic_inc(&chip->active); /* avoid autopm */
609 			break;
610 		}
611 	}
612 	if (! chip) {
613 		/* it's a fresh one.
614 		 * now look for an empty slot and create a new card instance
615 		 */
616 		for (i = 0; i < SNDRV_CARDS; i++)
617 			if (!usb_chip[i] &&
618 			    (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
619 			    (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
620 				if (enable[i]) {
621 					err = snd_usb_audio_create(intf, dev, i, quirk,
622 								   id, &chip);
623 					if (err < 0)
624 						goto __error;
625 					chip->pm_intf = intf;
626 					break;
627 				} else if (vid[i] != -1 || pid[i] != -1) {
628 					dev_info(&dev->dev,
629 						 "device (%04x:%04x) is disabled\n",
630 						 USB_ID_VENDOR(id),
631 						 USB_ID_PRODUCT(id));
632 					err = -ENOENT;
633 					goto __error;
634 				}
635 			}
636 		if (!chip) {
637 			dev_err(&dev->dev, "no available usb audio device\n");
638 			err = -ENODEV;
639 			goto __error;
640 		}
641 	}
642 	dev_set_drvdata(&dev->dev, chip);
643 
644 	/*
645 	 * For devices with more than one control interface, we assume the
646 	 * first contains the audio controls. We might need a more specific
647 	 * check here in the future.
648 	 */
649 	if (!chip->ctrl_intf)
650 		chip->ctrl_intf = alts;
651 
652 	chip->txfr_quirk = 0;
653 	err = 1; /* continue */
654 	if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
655 		/* need some special handlings */
656 		err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk);
657 		if (err < 0)
658 			goto __error;
659 	}
660 
661 	if (err > 0) {
662 		/* create normal USB audio interfaces */
663 		err = snd_usb_create_streams(chip, ifnum);
664 		if (err < 0)
665 			goto __error;
666 		err = snd_usb_create_mixer(chip, ifnum, ignore_ctl_error);
667 		if (err < 0)
668 			goto __error;
669 	}
670 
671 	/* we are allowed to call snd_card_register() many times */
672 	err = snd_card_register(chip->card);
673 	if (err < 0)
674 		goto __error;
675 
676 	usb_chip[chip->index] = chip;
677 	chip->num_interfaces++;
678 	usb_set_intfdata(intf, chip);
679 	atomic_dec(&chip->active);
680 	mutex_unlock(&register_mutex);
681 	return 0;
682 
683  __error:
684 	if (chip) {
685 		/* chip->active is inside the chip->card object,
686 		 * decrement before memory is possibly returned.
687 		 */
688 		atomic_dec(&chip->active);
689 		if (!chip->num_interfaces)
690 			snd_card_free(chip->card);
691 	}
692 	mutex_unlock(&register_mutex);
693 	return err;
694 }
695 
696 /*
697  * we need to take care of counter, since disconnection can be called also
698  * many times as well as usb_audio_probe().
699  */
700 static void usb_audio_disconnect(struct usb_interface *intf)
701 {
702 	struct snd_usb_audio *chip = usb_get_intfdata(intf);
703 	struct snd_card *card;
704 	struct list_head *p;
705 
706 	if (chip == (void *)-1L)
707 		return;
708 
709 	card = chip->card;
710 
711 	mutex_lock(&register_mutex);
712 	if (atomic_inc_return(&chip->shutdown) == 1) {
713 		struct snd_usb_stream *as;
714 		struct snd_usb_endpoint *ep;
715 		struct usb_mixer_interface *mixer;
716 
717 		/* wait until all pending tasks done;
718 		 * they are protected by snd_usb_lock_shutdown()
719 		 */
720 		wait_event(chip->shutdown_wait,
721 			   !atomic_read(&chip->usage_count));
722 		snd_card_disconnect(card);
723 		/* release the pcm resources */
724 		list_for_each_entry(as, &chip->pcm_list, list) {
725 			snd_usb_stream_disconnect(as);
726 		}
727 		/* release the endpoint resources */
728 		list_for_each_entry(ep, &chip->ep_list, list) {
729 			snd_usb_endpoint_release(ep);
730 		}
731 		/* release the midi resources */
732 		list_for_each(p, &chip->midi_list) {
733 			snd_usbmidi_disconnect(p);
734 		}
735 		/* release mixer resources */
736 		list_for_each_entry(mixer, &chip->mixer_list, list) {
737 			snd_usb_mixer_disconnect(mixer);
738 		}
739 	}
740 
741 	chip->num_interfaces--;
742 	if (chip->num_interfaces <= 0) {
743 		usb_chip[chip->index] = NULL;
744 		mutex_unlock(&register_mutex);
745 		snd_card_free_when_closed(card);
746 	} else {
747 		mutex_unlock(&register_mutex);
748 	}
749 }
750 
751 /* lock the shutdown (disconnect) task and autoresume */
752 int snd_usb_lock_shutdown(struct snd_usb_audio *chip)
753 {
754 	int err;
755 
756 	atomic_inc(&chip->usage_count);
757 	if (atomic_read(&chip->shutdown)) {
758 		err = -EIO;
759 		goto error;
760 	}
761 	err = snd_usb_autoresume(chip);
762 	if (err < 0)
763 		goto error;
764 	return 0;
765 
766  error:
767 	if (atomic_dec_and_test(&chip->usage_count))
768 		wake_up(&chip->shutdown_wait);
769 	return err;
770 }
771 
772 /* autosuspend and unlock the shutdown */
773 void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
774 {
775 	snd_usb_autosuspend(chip);
776 	if (atomic_dec_and_test(&chip->usage_count))
777 		wake_up(&chip->shutdown_wait);
778 }
779 
780 #ifdef CONFIG_PM
781 
782 int snd_usb_autoresume(struct snd_usb_audio *chip)
783 {
784 	if (atomic_read(&chip->shutdown))
785 		return -EIO;
786 	if (atomic_inc_return(&chip->active) == 1)
787 		return usb_autopm_get_interface(chip->pm_intf);
788 	return 0;
789 }
790 
791 void snd_usb_autosuspend(struct snd_usb_audio *chip)
792 {
793 	if (atomic_read(&chip->shutdown))
794 		return;
795 	if (atomic_dec_and_test(&chip->active))
796 		usb_autopm_put_interface(chip->pm_intf);
797 }
798 
799 static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
800 {
801 	struct snd_usb_audio *chip = usb_get_intfdata(intf);
802 	struct snd_usb_stream *as;
803 	struct usb_mixer_interface *mixer;
804 	struct list_head *p;
805 
806 	if (chip == (void *)-1L)
807 		return 0;
808 
809 	chip->autosuspended = !!PMSG_IS_AUTO(message);
810 	if (!chip->autosuspended)
811 		snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
812 	if (!chip->num_suspended_intf++) {
813 		list_for_each_entry(as, &chip->pcm_list, list) {
814 			snd_pcm_suspend_all(as->pcm);
815 			snd_usb_pcm_suspend(as);
816 			as->substream[0].need_setup_ep =
817 				as->substream[1].need_setup_ep = true;
818 		}
819 		list_for_each(p, &chip->midi_list)
820 			snd_usbmidi_suspend(p);
821 		list_for_each_entry(mixer, &chip->mixer_list, list)
822 			snd_usb_mixer_suspend(mixer);
823 	}
824 
825 	return 0;
826 }
827 
828 static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
829 {
830 	struct snd_usb_audio *chip = usb_get_intfdata(intf);
831 	struct snd_usb_stream *as;
832 	struct usb_mixer_interface *mixer;
833 	struct list_head *p;
834 	int err = 0;
835 
836 	if (chip == (void *)-1L)
837 		return 0;
838 	if (--chip->num_suspended_intf)
839 		return 0;
840 
841 	atomic_inc(&chip->active); /* avoid autopm */
842 
843 	list_for_each_entry(as, &chip->pcm_list, list) {
844 		err = snd_usb_pcm_resume(as);
845 		if (err < 0)
846 			goto err_out;
847 	}
848 
849 	/*
850 	 * ALSA leaves material resumption to user space
851 	 * we just notify and restart the mixers
852 	 */
853 	list_for_each_entry(mixer, &chip->mixer_list, list) {
854 		err = snd_usb_mixer_resume(mixer, reset_resume);
855 		if (err < 0)
856 			goto err_out;
857 	}
858 
859 	list_for_each(p, &chip->midi_list) {
860 		snd_usbmidi_resume(p);
861 	}
862 
863 	if (!chip->autosuspended)
864 		snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
865 	chip->autosuspended = 0;
866 
867 err_out:
868 	atomic_dec(&chip->active); /* allow autopm after this point */
869 	return err;
870 }
871 
872 static int usb_audio_resume(struct usb_interface *intf)
873 {
874 	return __usb_audio_resume(intf, false);
875 }
876 
877 static int usb_audio_reset_resume(struct usb_interface *intf)
878 {
879 	return __usb_audio_resume(intf, true);
880 }
881 #else
882 #define usb_audio_suspend	NULL
883 #define usb_audio_resume	NULL
884 #define usb_audio_reset_resume	NULL
885 #endif		/* CONFIG_PM */
886 
887 static const struct usb_device_id usb_audio_ids [] = {
888 #include "quirks-table.h"
889     { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
890       .bInterfaceClass = USB_CLASS_AUDIO,
891       .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
892     { }						/* Terminating entry */
893 };
894 MODULE_DEVICE_TABLE(usb, usb_audio_ids);
895 
896 /*
897  * entry point for linux usb interface
898  */
899 
900 static struct usb_driver usb_audio_driver = {
901 	.name =		"snd-usb-audio",
902 	.probe =	usb_audio_probe,
903 	.disconnect =	usb_audio_disconnect,
904 	.suspend =	usb_audio_suspend,
905 	.resume =	usb_audio_resume,
906 	.reset_resume =	usb_audio_reset_resume,
907 	.id_table =	usb_audio_ids,
908 	.supports_autosuspend = 1,
909 };
910 
911 module_usb_driver(usb_audio_driver);
912