ia64/kvm: compilation fix. export account_system_vtime.
[pv_ops_mirror.git] / sound / core / init.c
blobac0573416130d56b480caf2948a88f1017ad3bb8
1 /*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/init.h>
23 #include <linux/sched.h>
24 #include <linux/file.h>
25 #include <linux/slab.h>
26 #include <linux/time.h>
27 #include <linux/ctype.h>
28 #include <linux/pm.h>
30 #include <sound/core.h>
31 #include <sound/control.h>
32 #include <sound/info.h>
34 static DEFINE_SPINLOCK(shutdown_lock);
35 static LIST_HEAD(shutdown_files);
37 static const struct file_operations snd_shutdown_f_ops;
39 static unsigned int snd_cards_lock; /* locked for registering/using */
40 struct snd_card *snd_cards[SNDRV_CARDS];
41 EXPORT_SYMBOL(snd_cards);
43 static DEFINE_MUTEX(snd_card_mutex);
45 static char *slots[SNDRV_CARDS];
46 module_param_array(slots, charp, NULL, 0444);
47 MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
49 /* return non-zero if the given index is already reserved for another
50 * module via slots option
52 static int module_slot_mismatch(struct module *module, int idx)
54 #ifdef MODULE
55 char *s1, *s2;
56 if (!module || !module->name || !slots[idx])
57 return 0;
58 s1 = slots[idx];
59 s2 = module->name;
60 /* compare module name strings
61 * hyphens are handled as equivalent with underscore
63 for (;;) {
64 char c1 = *s1++;
65 char c2 = *s2++;
66 if (c1 == '-')
67 c1 = '_';
68 if (c2 == '-')
69 c2 = '_';
70 if (c1 != c2)
71 return 1;
72 if (!c1)
73 break;
75 #endif
76 return 0;
79 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
80 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
81 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
82 #endif
84 #ifdef CONFIG_PROC_FS
85 static void snd_card_id_read(struct snd_info_entry *entry,
86 struct snd_info_buffer *buffer)
88 snd_iprintf(buffer, "%s\n", entry->card->id);
91 static inline int init_info_for_card(struct snd_card *card)
93 int err;
94 struct snd_info_entry *entry;
96 if ((err = snd_info_card_register(card)) < 0) {
97 snd_printd("unable to create card info\n");
98 return err;
100 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
101 snd_printd("unable to create card entry\n");
102 return err;
104 entry->c.text.read = snd_card_id_read;
105 if (snd_info_register(entry) < 0) {
106 snd_info_free_entry(entry);
107 entry = NULL;
109 card->proc_id = entry;
110 return 0;
112 #else /* !CONFIG_PROC_FS */
113 #define init_info_for_card(card)
114 #endif
117 * snd_card_new - create and initialize a soundcard structure
118 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
119 * @xid: card identification (ASCII string)
120 * @module: top level module for locking
121 * @extra_size: allocate this extra size after the main soundcard structure
123 * Creates and initializes a soundcard structure.
125 * Returns kmallocated snd_card structure. Creates the ALSA control interface
126 * (which is blocked until snd_card_register function is called).
128 struct snd_card *snd_card_new(int idx, const char *xid,
129 struct module *module, int extra_size)
131 struct snd_card *card;
132 int err;
134 if (extra_size < 0)
135 extra_size = 0;
136 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
137 if (card == NULL)
138 return NULL;
139 if (xid) {
140 if (!snd_info_check_reserved_words(xid))
141 goto __error;
142 strlcpy(card->id, xid, sizeof(card->id));
144 err = 0;
145 mutex_lock(&snd_card_mutex);
146 if (idx < 0) {
147 int idx2;
148 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
149 /* idx == -1 == 0xffff means: take any free slot */
150 if (~snd_cards_lock & idx & 1<<idx2) {
151 if (module_slot_mismatch(module, idx2))
152 continue;
153 idx = idx2;
154 if (idx >= snd_ecards_limit)
155 snd_ecards_limit = idx + 1;
156 break;
158 } else {
159 if (idx < snd_ecards_limit) {
160 if (snd_cards_lock & (1 << idx))
161 err = -EBUSY; /* invalid */
162 } else {
163 if (idx < SNDRV_CARDS)
164 snd_ecards_limit = idx + 1; /* increase the limit */
165 else
166 err = -ENODEV;
169 if (idx < 0 || err < 0) {
170 mutex_unlock(&snd_card_mutex);
171 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
172 idx, snd_ecards_limit - 1, err);
173 goto __error;
175 snd_cards_lock |= 1 << idx; /* lock it */
176 mutex_unlock(&snd_card_mutex);
177 card->number = idx;
178 card->module = module;
179 INIT_LIST_HEAD(&card->devices);
180 init_rwsem(&card->controls_rwsem);
181 rwlock_init(&card->ctl_files_rwlock);
182 INIT_LIST_HEAD(&card->controls);
183 INIT_LIST_HEAD(&card->ctl_files);
184 spin_lock_init(&card->files_lock);
185 init_waitqueue_head(&card->shutdown_sleep);
186 #ifdef CONFIG_PM
187 mutex_init(&card->power_lock);
188 init_waitqueue_head(&card->power_sleep);
189 #endif
190 /* the control interface cannot be accessed from the user space until */
191 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
192 if ((err = snd_ctl_create(card)) < 0) {
193 snd_printd("unable to register control minors\n");
194 goto __error;
196 if ((err = snd_info_card_create(card)) < 0) {
197 snd_printd("unable to create card info\n");
198 goto __error_ctl;
200 if (extra_size > 0)
201 card->private_data = (char *)card + sizeof(struct snd_card);
202 return card;
204 __error_ctl:
205 snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
206 __error:
207 kfree(card);
208 return NULL;
211 EXPORT_SYMBOL(snd_card_new);
213 /* return non-zero if a card is already locked */
214 int snd_card_locked(int card)
216 int locked;
218 mutex_lock(&snd_card_mutex);
219 locked = snd_cards_lock & (1 << card);
220 mutex_unlock(&snd_card_mutex);
221 return locked;
224 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
226 return -ENODEV;
229 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
230 size_t count, loff_t *offset)
232 return -ENODEV;
235 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
236 size_t count, loff_t *offset)
238 return -ENODEV;
241 static int snd_disconnect_release(struct inode *inode, struct file *file)
243 struct snd_monitor_file *df = NULL, *_df;
245 spin_lock(&shutdown_lock);
246 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
247 if (_df->file == file) {
248 df = _df;
249 break;
252 spin_unlock(&shutdown_lock);
254 if (likely(df))
255 return df->disconnected_f_op->release(inode, file);
257 panic("%s(%p, %p) failed!", __func__, inode, file);
260 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
262 return POLLERR | POLLNVAL;
265 static long snd_disconnect_ioctl(struct file *file,
266 unsigned int cmd, unsigned long arg)
268 return -ENODEV;
271 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
273 return -ENODEV;
276 static int snd_disconnect_fasync(int fd, struct file *file, int on)
278 return -ENODEV;
281 static const struct file_operations snd_shutdown_f_ops =
283 .owner = THIS_MODULE,
284 .llseek = snd_disconnect_llseek,
285 .read = snd_disconnect_read,
286 .write = snd_disconnect_write,
287 .release = snd_disconnect_release,
288 .poll = snd_disconnect_poll,
289 .unlocked_ioctl = snd_disconnect_ioctl,
290 #ifdef CONFIG_COMPAT
291 .compat_ioctl = snd_disconnect_ioctl,
292 #endif
293 .mmap = snd_disconnect_mmap,
294 .fasync = snd_disconnect_fasync
298 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
299 * @card: soundcard structure
301 * Disconnects all APIs from the file-operations (user space).
303 * Returns zero, otherwise a negative error code.
305 * Note: The current implementation replaces all active file->f_op with special
306 * dummy file operations (they do nothing except release).
308 int snd_card_disconnect(struct snd_card *card)
310 struct snd_monitor_file *mfile;
311 struct file *file;
312 int err;
314 if (!card)
315 return -EINVAL;
317 spin_lock(&card->files_lock);
318 if (card->shutdown) {
319 spin_unlock(&card->files_lock);
320 return 0;
322 card->shutdown = 1;
323 spin_unlock(&card->files_lock);
325 /* phase 1: disable fops (user space) operations for ALSA API */
326 mutex_lock(&snd_card_mutex);
327 snd_cards[card->number] = NULL;
328 snd_cards_lock &= ~(1 << card->number);
329 mutex_unlock(&snd_card_mutex);
331 /* phase 2: replace file->f_op with special dummy operations */
333 spin_lock(&card->files_lock);
334 mfile = card->files;
335 while (mfile) {
336 file = mfile->file;
338 /* it's critical part, use endless loop */
339 /* we have no room to fail */
340 mfile->disconnected_f_op = mfile->file->f_op;
342 spin_lock(&shutdown_lock);
343 list_add(&mfile->shutdown_list, &shutdown_files);
344 spin_unlock(&shutdown_lock);
346 mfile->file->f_op = &snd_shutdown_f_ops;
347 fops_get(mfile->file->f_op);
349 mfile = mfile->next;
351 spin_unlock(&card->files_lock);
353 /* phase 3: notify all connected devices about disconnection */
354 /* at this point, they cannot respond to any calls except release() */
356 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
357 if (snd_mixer_oss_notify_callback)
358 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
359 #endif
361 /* notify all devices that we are disconnected */
362 err = snd_device_disconnect_all(card);
363 if (err < 0)
364 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
366 snd_info_card_disconnect(card);
367 #ifndef CONFIG_SYSFS_DEPRECATED
368 if (card->card_dev) {
369 device_unregister(card->card_dev);
370 card->card_dev = NULL;
372 #endif
373 #ifdef CONFIG_PM
374 wake_up(&card->power_sleep);
375 #endif
376 return 0;
379 EXPORT_SYMBOL(snd_card_disconnect);
382 * snd_card_free - frees given soundcard structure
383 * @card: soundcard structure
385 * This function releases the soundcard structure and the all assigned
386 * devices automatically. That is, you don't have to release the devices
387 * by yourself.
389 * Returns zero. Frees all associated devices and frees the control
390 * interface associated to given soundcard.
392 static int snd_card_do_free(struct snd_card *card)
394 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
395 if (snd_mixer_oss_notify_callback)
396 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
397 #endif
398 if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
399 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
400 /* Fatal, but this situation should never occur */
402 if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
403 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
404 /* Fatal, but this situation should never occur */
406 if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
407 snd_printk(KERN_ERR "unable to free all devices (post)\n");
408 /* Fatal, but this situation should never occur */
410 if (card->private_free)
411 card->private_free(card);
412 snd_info_free_entry(card->proc_id);
413 if (snd_info_card_free(card) < 0) {
414 snd_printk(KERN_WARNING "unable to free card info\n");
415 /* Not fatal error */
417 kfree(card);
418 return 0;
421 int snd_card_free_when_closed(struct snd_card *card)
423 int free_now = 0;
424 int ret = snd_card_disconnect(card);
425 if (ret)
426 return ret;
428 spin_lock(&card->files_lock);
429 if (card->files == NULL)
430 free_now = 1;
431 else
432 card->free_on_last_close = 1;
433 spin_unlock(&card->files_lock);
435 if (free_now)
436 snd_card_do_free(card);
437 return 0;
440 EXPORT_SYMBOL(snd_card_free_when_closed);
442 int snd_card_free(struct snd_card *card)
444 int ret = snd_card_disconnect(card);
445 if (ret)
446 return ret;
448 /* wait, until all devices are ready for the free operation */
449 wait_event(card->shutdown_sleep, card->files == NULL);
450 snd_card_do_free(card);
451 return 0;
454 EXPORT_SYMBOL(snd_card_free);
456 static void choose_default_id(struct snd_card *card)
458 int i, len, idx_flag = 0, loops = SNDRV_CARDS;
459 char *id, *spos;
461 id = spos = card->shortname;
462 while (*id != '\0') {
463 if (*id == ' ')
464 spos = id + 1;
465 id++;
467 id = card->id;
468 while (*spos != '\0' && !isalnum(*spos))
469 spos++;
470 if (isdigit(*spos))
471 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
472 while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
473 if (isalnum(*spos))
474 *id++ = *spos;
475 spos++;
477 *id = '\0';
479 id = card->id;
481 if (*id == '\0')
482 strcpy(id, "default");
484 while (1) {
485 if (loops-- == 0) {
486 snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
487 strcpy(card->id, card->proc_root->name);
488 return;
490 if (!snd_info_check_reserved_words(id))
491 goto __change;
492 for (i = 0; i < snd_ecards_limit; i++) {
493 if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
494 goto __change;
496 break;
498 __change:
499 len = strlen(id);
500 if (idx_flag) {
501 if (id[len-1] != '9')
502 id[len-1]++;
503 else
504 id[len-1] = 'A';
505 } else if ((size_t)len <= sizeof(card->id) - 3) {
506 strcat(id, "_1");
507 idx_flag++;
508 } else {
509 spos = id + len - 2;
510 if ((size_t)len <= sizeof(card->id) - 2)
511 spos++;
512 *spos++ = '_';
513 *spos++ = '1';
514 *spos++ = '\0';
515 idx_flag++;
521 * snd_card_register - register the soundcard
522 * @card: soundcard structure
524 * This function registers all the devices assigned to the soundcard.
525 * Until calling this, the ALSA control interface is blocked from the
526 * external accesses. Thus, you should call this function at the end
527 * of the initialization of the card.
529 * Returns zero otherwise a negative error code if the registrain failed.
531 int snd_card_register(struct snd_card *card)
533 int err;
535 snd_assert(card != NULL, return -EINVAL);
536 #ifndef CONFIG_SYSFS_DEPRECATED
537 if (!card->card_dev) {
538 card->card_dev = device_create(sound_class, card->dev, 0,
539 "card%i", card->number);
540 if (IS_ERR(card->card_dev))
541 card->card_dev = NULL;
543 #endif
544 if ((err = snd_device_register_all(card)) < 0)
545 return err;
546 mutex_lock(&snd_card_mutex);
547 if (snd_cards[card->number]) {
548 /* already registered */
549 mutex_unlock(&snd_card_mutex);
550 return 0;
552 if (card->id[0] == '\0')
553 choose_default_id(card);
554 snd_cards[card->number] = card;
555 mutex_unlock(&snd_card_mutex);
556 init_info_for_card(card);
557 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
558 if (snd_mixer_oss_notify_callback)
559 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
560 #endif
561 return 0;
564 EXPORT_SYMBOL(snd_card_register);
566 #ifdef CONFIG_PROC_FS
567 static struct snd_info_entry *snd_card_info_entry;
569 static void snd_card_info_read(struct snd_info_entry *entry,
570 struct snd_info_buffer *buffer)
572 int idx, count;
573 struct snd_card *card;
575 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
576 mutex_lock(&snd_card_mutex);
577 if ((card = snd_cards[idx]) != NULL) {
578 count++;
579 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
580 idx,
581 card->id,
582 card->driver,
583 card->shortname);
584 snd_iprintf(buffer, " %s\n",
585 card->longname);
587 mutex_unlock(&snd_card_mutex);
589 if (!count)
590 snd_iprintf(buffer, "--- no soundcards ---\n");
593 #ifdef CONFIG_SND_OSSEMUL
595 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
597 int idx, count;
598 struct snd_card *card;
600 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
601 mutex_lock(&snd_card_mutex);
602 if ((card = snd_cards[idx]) != NULL) {
603 count++;
604 snd_iprintf(buffer, "%s\n", card->longname);
606 mutex_unlock(&snd_card_mutex);
608 if (!count) {
609 snd_iprintf(buffer, "--- no soundcards ---\n");
613 #endif
615 #ifdef MODULE
616 static struct snd_info_entry *snd_card_module_info_entry;
617 static void snd_card_module_info_read(struct snd_info_entry *entry,
618 struct snd_info_buffer *buffer)
620 int idx;
621 struct snd_card *card;
623 for (idx = 0; idx < SNDRV_CARDS; idx++) {
624 mutex_lock(&snd_card_mutex);
625 if ((card = snd_cards[idx]) != NULL)
626 snd_iprintf(buffer, "%2i %s\n",
627 idx, card->module->name);
628 mutex_unlock(&snd_card_mutex);
631 #endif
633 int __init snd_card_info_init(void)
635 struct snd_info_entry *entry;
637 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
638 if (! entry)
639 return -ENOMEM;
640 entry->c.text.read = snd_card_info_read;
641 if (snd_info_register(entry) < 0) {
642 snd_info_free_entry(entry);
643 return -ENOMEM;
645 snd_card_info_entry = entry;
647 #ifdef MODULE
648 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
649 if (entry) {
650 entry->c.text.read = snd_card_module_info_read;
651 if (snd_info_register(entry) < 0)
652 snd_info_free_entry(entry);
653 else
654 snd_card_module_info_entry = entry;
656 #endif
658 return 0;
661 int __exit snd_card_info_done(void)
663 snd_info_free_entry(snd_card_info_entry);
664 #ifdef MODULE
665 snd_info_free_entry(snd_card_module_info_entry);
666 #endif
667 return 0;
670 #endif /* CONFIG_PROC_FS */
673 * snd_component_add - add a component string
674 * @card: soundcard structure
675 * @component: the component id string
677 * This function adds the component id string to the supported list.
678 * The component can be referred from the alsa-lib.
680 * Returns zero otherwise a negative error code.
683 int snd_component_add(struct snd_card *card, const char *component)
685 char *ptr;
686 int len = strlen(component);
688 ptr = strstr(card->components, component);
689 if (ptr != NULL) {
690 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
691 return 1;
693 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
694 snd_BUG();
695 return -ENOMEM;
697 if (card->components[0] != '\0')
698 strcat(card->components, " ");
699 strcat(card->components, component);
700 return 0;
703 EXPORT_SYMBOL(snd_component_add);
706 * snd_card_file_add - add the file to the file list of the card
707 * @card: soundcard structure
708 * @file: file pointer
710 * This function adds the file to the file linked-list of the card.
711 * This linked-list is used to keep tracking the connection state,
712 * and to avoid the release of busy resources by hotplug.
714 * Returns zero or a negative error code.
716 int snd_card_file_add(struct snd_card *card, struct file *file)
718 struct snd_monitor_file *mfile;
720 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
721 if (mfile == NULL)
722 return -ENOMEM;
723 mfile->file = file;
724 mfile->disconnected_f_op = NULL;
725 mfile->next = NULL;
726 spin_lock(&card->files_lock);
727 if (card->shutdown) {
728 spin_unlock(&card->files_lock);
729 kfree(mfile);
730 return -ENODEV;
732 mfile->next = card->files;
733 card->files = mfile;
734 spin_unlock(&card->files_lock);
735 return 0;
738 EXPORT_SYMBOL(snd_card_file_add);
741 * snd_card_file_remove - remove the file from the file list
742 * @card: soundcard structure
743 * @file: file pointer
745 * This function removes the file formerly added to the card via
746 * snd_card_file_add() function.
747 * If all files are removed and snd_card_free_when_closed() was
748 * called beforehand, it processes the pending release of
749 * resources.
751 * Returns zero or a negative error code.
753 int snd_card_file_remove(struct snd_card *card, struct file *file)
755 struct snd_monitor_file *mfile, *pfile = NULL;
756 int last_close = 0;
758 spin_lock(&card->files_lock);
759 mfile = card->files;
760 while (mfile) {
761 if (mfile->file == file) {
762 if (pfile)
763 pfile->next = mfile->next;
764 else
765 card->files = mfile->next;
766 break;
768 pfile = mfile;
769 mfile = mfile->next;
771 if (mfile && mfile->disconnected_f_op) {
772 fops_put(mfile->disconnected_f_op);
773 spin_lock(&shutdown_lock);
774 list_del(&mfile->shutdown_list);
775 spin_unlock(&shutdown_lock);
777 if (card->files == NULL)
778 last_close = 1;
779 spin_unlock(&card->files_lock);
780 if (last_close) {
781 wake_up(&card->shutdown_sleep);
782 if (card->free_on_last_close)
783 snd_card_do_free(card);
785 if (!mfile) {
786 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
787 return -ENOENT;
789 kfree(mfile);
790 return 0;
793 EXPORT_SYMBOL(snd_card_file_remove);
795 #ifdef CONFIG_PM
797 * snd_power_wait - wait until the power-state is changed.
798 * @card: soundcard structure
799 * @power_state: expected power state
801 * Waits until the power-state is changed.
803 * Note: the power lock must be active before call.
805 int snd_power_wait(struct snd_card *card, unsigned int power_state)
807 wait_queue_t wait;
808 int result = 0;
810 /* fastpath */
811 if (snd_power_get_state(card) == power_state)
812 return 0;
813 init_waitqueue_entry(&wait, current);
814 add_wait_queue(&card->power_sleep, &wait);
815 while (1) {
816 if (card->shutdown) {
817 result = -ENODEV;
818 break;
820 if (snd_power_get_state(card) == power_state)
821 break;
822 set_current_state(TASK_UNINTERRUPTIBLE);
823 snd_power_unlock(card);
824 schedule_timeout(30 * HZ);
825 snd_power_lock(card);
827 remove_wait_queue(&card->power_sleep, &wait);
828 return result;
831 EXPORT_SYMBOL(snd_power_wait);
832 #endif /* CONFIG_PM */