Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6/btrfs-unstable.git] / sound / core / init.c
blobd9ee27ae9a510a2a1e5ff23e767fda896a9e5e37
1 /*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
23 #include <linux/init.h>
24 #include <linux/sched.h>
25 #include <linux/file.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/ctype.h>
29 #include <linux/pci.h>
30 #include <linux/pm.h>
31 #include <linux/platform_device.h>
33 #include <sound/core.h>
34 #include <sound/control.h>
35 #include <sound/info.h>
37 struct snd_shutdown_f_ops {
38 struct file_operations f_ops;
39 struct snd_shutdown_f_ops *next;
42 unsigned int snd_cards_lock = 0; /* locked for registering/using */
43 snd_card_t *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL};
44 DEFINE_RWLOCK(snd_card_rwlock);
46 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
47 int (*snd_mixer_oss_notify_callback)(snd_card_t *card, int free_flag);
48 #endif
50 static void snd_card_id_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
52 snd_iprintf(buffer, "%s\n", entry->card->id);
55 static void snd_card_free_thread(void * __card);
57 /**
58 * snd_card_new - create and initialize a soundcard structure
59 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
60 * @xid: card identification (ASCII string)
61 * @module: top level module for locking
62 * @extra_size: allocate this extra size after the main soundcard structure
64 * Creates and initializes a soundcard structure.
66 * Returns kmallocated snd_card_t structure. Creates the ALSA control interface
67 * (which is blocked until snd_card_register function is called).
69 snd_card_t *snd_card_new(int idx, const char *xid,
70 struct module *module, int extra_size)
72 snd_card_t *card;
73 int err;
75 if (extra_size < 0)
76 extra_size = 0;
77 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
78 if (card == NULL)
79 return NULL;
80 if (xid) {
81 if (!snd_info_check_reserved_words(xid))
82 goto __error;
83 strlcpy(card->id, xid, sizeof(card->id));
85 err = 0;
86 write_lock(&snd_card_rwlock);
87 if (idx < 0) {
88 int idx2;
89 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
90 if (~snd_cards_lock & idx & 1<<idx2) {
91 idx = idx2;
92 if (idx >= snd_ecards_limit)
93 snd_ecards_limit = idx + 1;
94 break;
96 } else if (idx < snd_ecards_limit) {
97 if (snd_cards_lock & (1 << idx))
98 err = -ENODEV; /* invalid */
99 } else if (idx < SNDRV_CARDS)
100 snd_ecards_limit = idx + 1; /* increase the limit */
101 else
102 err = -ENODEV;
103 if (idx < 0 || err < 0) {
104 write_unlock(&snd_card_rwlock);
105 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1);
106 goto __error;
108 snd_cards_lock |= 1 << idx; /* lock it */
109 write_unlock(&snd_card_rwlock);
110 card->number = idx;
111 card->module = module;
112 INIT_LIST_HEAD(&card->devices);
113 init_rwsem(&card->controls_rwsem);
114 rwlock_init(&card->ctl_files_rwlock);
115 INIT_LIST_HEAD(&card->controls);
116 INIT_LIST_HEAD(&card->ctl_files);
117 spin_lock_init(&card->files_lock);
118 init_waitqueue_head(&card->shutdown_sleep);
119 INIT_WORK(&card->free_workq, snd_card_free_thread, card);
120 #ifdef CONFIG_PM
121 init_MUTEX(&card->power_lock);
122 init_waitqueue_head(&card->power_sleep);
123 #endif
124 /* the control interface cannot be accessed from the user space until */
125 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
126 if ((err = snd_ctl_create(card)) < 0) {
127 snd_printd("unable to register control minors\n");
128 goto __error;
130 if ((err = snd_info_card_create(card)) < 0) {
131 snd_printd("unable to create card info\n");
132 goto __error_ctl;
134 if (extra_size > 0)
135 card->private_data = (char *)card + sizeof(snd_card_t);
136 return card;
138 __error_ctl:
139 snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
140 __error:
141 kfree(card);
142 return NULL;
145 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
147 return POLLERR | POLLNVAL;
151 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
152 * @card: soundcard structure
154 * Disconnects all APIs from the file-operations (user space).
156 * Returns zero, otherwise a negative error code.
158 * Note: The current implementation replaces all active file->f_op with special
159 * dummy file operations (they do nothing except release).
161 int snd_card_disconnect(snd_card_t * card)
163 struct snd_monitor_file *mfile;
164 struct file *file;
165 struct snd_shutdown_f_ops *s_f_ops;
166 struct file_operations *f_ops, *old_f_ops;
167 int err;
169 spin_lock(&card->files_lock);
170 if (card->shutdown) {
171 spin_unlock(&card->files_lock);
172 return 0;
174 card->shutdown = 1;
175 spin_unlock(&card->files_lock);
177 /* phase 1: disable fops (user space) operations for ALSA API */
178 write_lock(&snd_card_rwlock);
179 snd_cards[card->number] = NULL;
180 write_unlock(&snd_card_rwlock);
182 /* phase 2: replace file->f_op with special dummy operations */
184 spin_lock(&card->files_lock);
185 mfile = card->files;
186 while (mfile) {
187 file = mfile->file;
189 /* it's critical part, use endless loop */
190 /* we have no room to fail */
191 s_f_ops = kmalloc(sizeof(struct snd_shutdown_f_ops), GFP_ATOMIC);
192 if (s_f_ops == NULL)
193 panic("Atomic allocation failed for snd_shutdown_f_ops!");
195 f_ops = &s_f_ops->f_ops;
197 memset(f_ops, 0, sizeof(*f_ops));
198 f_ops->owner = file->f_op->owner;
199 f_ops->release = file->f_op->release;
200 f_ops->poll = snd_disconnect_poll;
202 s_f_ops->next = card->s_f_ops;
203 card->s_f_ops = s_f_ops;
205 f_ops = fops_get(f_ops);
207 old_f_ops = file->f_op;
208 file->f_op = f_ops; /* must be atomic */
209 fops_put(old_f_ops);
211 mfile = mfile->next;
213 spin_unlock(&card->files_lock);
215 /* phase 3: notify all connected devices about disconnection */
216 /* at this point, they cannot respond to any calls except release() */
218 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
219 if (snd_mixer_oss_notify_callback)
220 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
221 #endif
223 /* notify all devices that we are disconnected */
224 err = snd_device_disconnect_all(card);
225 if (err < 0)
226 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
228 return 0;
231 #ifdef CONFIG_SND_GENERIC_DRIVER
232 static void snd_generic_device_unregister(snd_card_t *card);
233 #else
234 #define snd_generic_device_unregister(x) /*NOP*/
235 #endif
238 * snd_card_free - frees given soundcard structure
239 * @card: soundcard structure
241 * This function releases the soundcard structure and the all assigned
242 * devices automatically. That is, you don't have to release the devices
243 * by yourself.
245 * Returns zero. Frees all associated devices and frees the control
246 * interface associated to given soundcard.
248 int snd_card_free(snd_card_t * card)
250 struct snd_shutdown_f_ops *s_f_ops;
252 if (card == NULL)
253 return -EINVAL;
254 write_lock(&snd_card_rwlock);
255 snd_cards[card->number] = NULL;
256 write_unlock(&snd_card_rwlock);
258 #ifdef CONFIG_PM
259 wake_up(&card->power_sleep);
260 #endif
261 /* wait, until all devices are ready for the free operation */
262 wait_event(card->shutdown_sleep, card->files == NULL);
264 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
265 if (snd_mixer_oss_notify_callback)
266 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
267 #endif
268 if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
269 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
270 /* Fatal, but this situation should never occur */
272 if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
273 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
274 /* Fatal, but this situation should never occur */
276 if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
277 snd_printk(KERN_ERR "unable to free all devices (post)\n");
278 /* Fatal, but this situation should never occur */
280 if (card->private_free)
281 card->private_free(card);
282 if (card->proc_id)
283 snd_info_unregister(card->proc_id);
284 if (snd_info_card_free(card) < 0) {
285 snd_printk(KERN_WARNING "unable to free card info\n");
286 /* Not fatal error */
288 snd_generic_device_unregister(card);
289 while (card->s_f_ops) {
290 s_f_ops = card->s_f_ops;
291 card->s_f_ops = s_f_ops->next;
292 kfree(s_f_ops);
294 write_lock(&snd_card_rwlock);
295 snd_cards_lock &= ~(1 << card->number);
296 write_unlock(&snd_card_rwlock);
297 kfree(card);
298 return 0;
301 static void snd_card_free_thread(void * __card)
303 snd_card_t *card = __card;
304 struct module * module = card->module;
306 if (!try_module_get(module)) {
307 snd_printk(KERN_ERR "unable to lock toplevel module for card %i in free thread\n", card->number);
308 module = NULL;
311 snd_card_free(card);
313 module_put(module);
317 * snd_card_free_in_thread - call snd_card_free() in thread
318 * @card: soundcard structure
320 * This function schedules the call of snd_card_free() function in a
321 * work queue. When all devices are released (non-busy), the work
322 * is woken up and calls snd_card_free().
324 * When a card can be disconnected at any time by hotplug service,
325 * this function should be used in disconnect (or detach) callback
326 * instead of calling snd_card_free() directly.
328 * Returns - zero otherwise a negative error code if the start of thread failed.
330 int snd_card_free_in_thread(snd_card_t * card)
332 if (card->files == NULL) {
333 snd_card_free(card);
334 return 0;
337 if (schedule_work(&card->free_workq))
338 return 0;
340 snd_printk(KERN_ERR "schedule_work() failed in snd_card_free_in_thread for card %i\n", card->number);
341 /* try to free the structure immediately */
342 snd_card_free(card);
343 return -EFAULT;
346 static void choose_default_id(snd_card_t * card)
348 int i, len, idx_flag = 0, loops = 8;
349 char *id, *spos;
351 id = spos = card->shortname;
352 while (*id != '\0') {
353 if (*id == ' ')
354 spos = id + 1;
355 id++;
357 id = card->id;
358 while (*spos != '\0' && !isalnum(*spos))
359 spos++;
360 if (isdigit(*spos))
361 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
362 while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
363 if (isalnum(*spos))
364 *id++ = *spos;
365 spos++;
367 *id = '\0';
369 id = card->id;
371 if (*id == '\0')
372 strcpy(id, "default");
374 while (1) {
375 if (loops-- == 0) {
376 snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
377 strcpy(card->id, card->proc_root->name);
378 return;
380 if (!snd_info_check_reserved_words(id))
381 goto __change;
382 for (i = 0; i < snd_ecards_limit; i++) {
383 if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
384 goto __change;
386 break;
388 __change:
389 len = strlen(id);
390 if (idx_flag)
391 id[len-1]++;
392 else if ((size_t)len <= sizeof(card->id) - 3) {
393 strcat(id, "_1");
394 idx_flag++;
395 } else {
396 spos = id + len - 2;
397 if ((size_t)len <= sizeof(card->id) - 2)
398 spos++;
399 *spos++ = '_';
400 *spos++ = '1';
401 *spos++ = '\0';
402 idx_flag++;
408 * snd_card_register - register the soundcard
409 * @card: soundcard structure
411 * This function registers all the devices assigned to the soundcard.
412 * Until calling this, the ALSA control interface is blocked from the
413 * external accesses. Thus, you should call this function at the end
414 * of the initialization of the card.
416 * Returns zero otherwise a negative error code if the registrain failed.
418 int snd_card_register(snd_card_t * card)
420 int err;
421 snd_info_entry_t *entry;
423 snd_assert(card != NULL, return -EINVAL);
424 if ((err = snd_device_register_all(card)) < 0)
425 return err;
426 write_lock(&snd_card_rwlock);
427 if (snd_cards[card->number]) {
428 /* already registered */
429 write_unlock(&snd_card_rwlock);
430 return 0;
432 if (card->id[0] == '\0')
433 choose_default_id(card);
434 snd_cards[card->number] = card;
435 write_unlock(&snd_card_rwlock);
436 if ((err = snd_info_card_register(card)) < 0) {
437 snd_printd("unable to create card info\n");
438 goto __skip_info;
440 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
441 snd_printd("unable to create card entry\n");
442 goto __skip_info;
444 entry->c.text.read_size = PAGE_SIZE;
445 entry->c.text.read = snd_card_id_read;
446 if (snd_info_register(entry) < 0) {
447 snd_info_free_entry(entry);
448 entry = NULL;
450 card->proc_id = entry;
451 __skip_info:
452 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
453 if (snd_mixer_oss_notify_callback)
454 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
455 #endif
456 return 0;
459 static snd_info_entry_t *snd_card_info_entry = NULL;
461 static void snd_card_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
463 int idx, count;
464 snd_card_t *card;
466 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
467 read_lock(&snd_card_rwlock);
468 if ((card = snd_cards[idx]) != NULL) {
469 count++;
470 snd_iprintf(buffer, "%i [%-15s]: %s - %s\n",
471 idx,
472 card->id,
473 card->driver,
474 card->shortname);
475 snd_iprintf(buffer, " %s\n",
476 card->longname);
478 read_unlock(&snd_card_rwlock);
480 if (!count)
481 snd_iprintf(buffer, "--- no soundcards ---\n");
484 #if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
486 void snd_card_info_read_oss(snd_info_buffer_t * buffer)
488 int idx, count;
489 snd_card_t *card;
491 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
492 read_lock(&snd_card_rwlock);
493 if ((card = snd_cards[idx]) != NULL) {
494 count++;
495 snd_iprintf(buffer, "%s\n", card->longname);
497 read_unlock(&snd_card_rwlock);
499 if (!count) {
500 snd_iprintf(buffer, "--- no soundcards ---\n");
504 #endif
506 #ifdef MODULE
507 static snd_info_entry_t *snd_card_module_info_entry;
508 static void snd_card_module_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
510 int idx;
511 snd_card_t *card;
513 for (idx = 0; idx < SNDRV_CARDS; idx++) {
514 read_lock(&snd_card_rwlock);
515 if ((card = snd_cards[idx]) != NULL)
516 snd_iprintf(buffer, "%i %s\n", idx, card->module->name);
517 read_unlock(&snd_card_rwlock);
520 #endif
522 int __init snd_card_info_init(void)
524 snd_info_entry_t *entry;
526 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
527 if (! entry)
528 return -ENOMEM;
529 entry->c.text.read_size = PAGE_SIZE;
530 entry->c.text.read = snd_card_info_read;
531 if (snd_info_register(entry) < 0) {
532 snd_info_free_entry(entry);
533 return -ENOMEM;
535 snd_card_info_entry = entry;
537 #ifdef MODULE
538 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
539 if (entry) {
540 entry->c.text.read_size = PAGE_SIZE;
541 entry->c.text.read = snd_card_module_info_read;
542 if (snd_info_register(entry) < 0)
543 snd_info_free_entry(entry);
544 else
545 snd_card_module_info_entry = entry;
547 #endif
549 return 0;
552 int __exit snd_card_info_done(void)
554 if (snd_card_info_entry)
555 snd_info_unregister(snd_card_info_entry);
556 #ifdef MODULE
557 if (snd_card_module_info_entry)
558 snd_info_unregister(snd_card_module_info_entry);
559 #endif
560 return 0;
564 * snd_component_add - add a component string
565 * @card: soundcard structure
566 * @component: the component id string
568 * This function adds the component id string to the supported list.
569 * The component can be referred from the alsa-lib.
571 * Returns zero otherwise a negative error code.
574 int snd_component_add(snd_card_t *card, const char *component)
576 char *ptr;
577 int len = strlen(component);
579 ptr = strstr(card->components, component);
580 if (ptr != NULL) {
581 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
582 return 1;
584 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
585 snd_BUG();
586 return -ENOMEM;
588 if (card->components[0] != '\0')
589 strcat(card->components, " ");
590 strcat(card->components, component);
591 return 0;
595 * snd_card_file_add - add the file to the file list of the card
596 * @card: soundcard structure
597 * @file: file pointer
599 * This function adds the file to the file linked-list of the card.
600 * This linked-list is used to keep tracking the connection state,
601 * and to avoid the release of busy resources by hotplug.
603 * Returns zero or a negative error code.
605 int snd_card_file_add(snd_card_t *card, struct file *file)
607 struct snd_monitor_file *mfile;
609 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
610 if (mfile == NULL)
611 return -ENOMEM;
612 mfile->file = file;
613 mfile->next = NULL;
614 spin_lock(&card->files_lock);
615 if (card->shutdown) {
616 spin_unlock(&card->files_lock);
617 kfree(mfile);
618 return -ENODEV;
620 mfile->next = card->files;
621 card->files = mfile;
622 spin_unlock(&card->files_lock);
623 return 0;
627 * snd_card_file_remove - remove the file from the file list
628 * @card: soundcard structure
629 * @file: file pointer
631 * This function removes the file formerly added to the card via
632 * snd_card_file_add() function.
633 * If all files are removed and the release of the card is
634 * scheduled, it will wake up the the thread to call snd_card_free()
635 * (see snd_card_free_in_thread() function).
637 * Returns zero or a negative error code.
639 int snd_card_file_remove(snd_card_t *card, struct file *file)
641 struct snd_monitor_file *mfile, *pfile = NULL;
643 spin_lock(&card->files_lock);
644 mfile = card->files;
645 while (mfile) {
646 if (mfile->file == file) {
647 if (pfile)
648 pfile->next = mfile->next;
649 else
650 card->files = mfile->next;
651 break;
653 pfile = mfile;
654 mfile = mfile->next;
656 spin_unlock(&card->files_lock);
657 if (card->files == NULL)
658 wake_up(&card->shutdown_sleep);
659 if (!mfile) {
660 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
661 return -ENOENT;
663 kfree(mfile);
664 return 0;
667 #ifdef CONFIG_SND_GENERIC_DRIVER
669 * generic device without a proper bus using platform_device
670 * (e.g. ISA)
672 struct snd_generic_device {
673 struct platform_device pdev;
674 snd_card_t *card;
677 #define get_snd_generic_card(dev) container_of(to_platform_device(dev), struct snd_generic_device, pdev)->card
679 #define SND_GENERIC_NAME "snd_generic"
681 #ifdef CONFIG_PM
682 static int snd_generic_suspend(struct device *dev, pm_message_t state);
683 static int snd_generic_resume(struct device *dev);
684 #endif
686 /* initialized in sound.c */
687 struct device_driver snd_generic_driver = {
688 .name = SND_GENERIC_NAME,
689 .bus = &platform_bus_type,
690 #ifdef CONFIG_PM
691 .suspend = snd_generic_suspend,
692 .resume = snd_generic_resume,
693 #endif
696 void snd_generic_device_release(struct device *dev)
700 static int snd_generic_device_register(snd_card_t *card)
702 struct snd_generic_device *dev;
703 int err;
705 if (card->generic_dev)
706 return 0; /* already registered */
708 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
709 if (! dev) {
710 snd_printk(KERN_ERR "can't allocate generic_device\n");
711 return -ENOMEM;
714 dev->pdev.name = SND_GENERIC_NAME;
715 dev->pdev.id = card->number;
716 dev->pdev.dev.release = snd_generic_device_release;
717 dev->card = card;
718 if ((err = platform_device_register(&dev->pdev)) < 0) {
719 kfree(dev);
720 return err;
722 card->generic_dev = dev;
723 return 0;
726 static void snd_generic_device_unregister(snd_card_t *card)
728 struct snd_generic_device *dev = card->generic_dev;
729 if (dev) {
730 platform_device_unregister(&dev->pdev);
731 kfree(dev);
732 card->generic_dev = NULL;
737 * snd_card_set_generic_dev - assign the generic device to the card
738 * @card: soundcard structure
740 * Assigns a generic device to the card. This function is provided as the
741 * last resort, for devices without any proper bus. Thus this won't override
742 * the device already assigned to the card.
744 * Returns zero if successful, or a negative error code.
746 int snd_card_set_generic_dev(snd_card_t *card)
748 int err;
749 if ((err = snd_generic_device_register(card)) < 0)
750 return err;
751 if (! card->dev)
752 snd_card_set_dev(card, &card->generic_dev->pdev.dev);
753 return 0;
755 #endif /* CONFIG_SND_GENERIC_DRIVER */
757 #ifdef CONFIG_PM
759 * snd_power_wait - wait until the power-state is changed.
760 * @card: soundcard structure
761 * @power_state: expected power state
762 * @file: file structure for the O_NONBLOCK check (optional)
764 * Waits until the power-state is changed.
766 * Note: the power lock must be active before call.
768 int snd_power_wait(snd_card_t *card, unsigned int power_state, struct file *file)
770 wait_queue_t wait;
771 int result = 0;
773 /* fastpath */
774 if (snd_power_get_state(card) == power_state)
775 return 0;
776 init_waitqueue_entry(&wait, current);
777 add_wait_queue(&card->power_sleep, &wait);
778 while (1) {
779 if (card->shutdown) {
780 result = -ENODEV;
781 break;
783 if (snd_power_get_state(card) == power_state)
784 break;
785 #if 0 /* block all devices */
786 if (file && (file->f_flags & O_NONBLOCK)) {
787 result = -EAGAIN;
788 break;
790 #endif
791 set_current_state(TASK_UNINTERRUPTIBLE);
792 snd_power_unlock(card);
793 schedule_timeout(30 * HZ);
794 snd_power_lock(card);
796 remove_wait_queue(&card->power_sleep, &wait);
797 return result;
801 * snd_card_set_pm_callback - set the PCI power-management callbacks
802 * @card: soundcard structure
803 * @suspend: suspend callback function
804 * @resume: resume callback function
805 * @private_data: private data to pass to the callback functions
807 * Sets the power-management callback functions of the card.
808 * These callbacks are called from ALSA's common PCI suspend/resume
809 * handler and from the control API.
811 int snd_card_set_pm_callback(snd_card_t *card,
812 int (*suspend)(snd_card_t *, pm_message_t),
813 int (*resume)(snd_card_t *),
814 void *private_data)
816 card->pm_suspend = suspend;
817 card->pm_resume = resume;
818 card->pm_private_data = private_data;
819 return 0;
822 #ifdef CONFIG_SND_GENERIC_DRIVER
823 /* suspend/resume callbacks for snd_generic platform device */
824 static int snd_generic_suspend(struct device *dev, pm_message_t state)
826 snd_card_t *card;
828 card = get_snd_generic_card(dev);
829 if (card->power_state == SNDRV_CTL_POWER_D3hot)
830 return 0;
831 if (card->pm_suspend)
832 card->pm_suspend(card, PMSG_SUSPEND);
833 snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
834 return 0;
837 static int snd_generic_resume(struct device *dev)
839 snd_card_t *card;
841 card = get_snd_generic_card(dev);
842 if (card->power_state == SNDRV_CTL_POWER_D0)
843 return 0;
844 if (card->pm_resume)
845 card->pm_resume(card);
846 snd_power_change_state(card, SNDRV_CTL_POWER_D0);
847 return 0;
851 * snd_card_set_generic_pm_callback - set the generic power-management callbacks
852 * @card: soundcard structure
853 * @suspend: suspend callback function
854 * @resume: resume callback function
855 * @private_data: private data to pass to the callback functions
857 * Registers the power-management and sets the lowlevel callbacks for
858 * the given card. These callbacks are called from the ALSA's common
859 * PM handler and from the control API.
861 int snd_card_set_generic_pm_callback(snd_card_t *card,
862 int (*suspend)(snd_card_t *, pm_message_t),
863 int (*resume)(snd_card_t *),
864 void *private_data)
866 int err;
867 if ((err = snd_generic_device_register(card)) < 0)
868 return err;
869 return snd_card_set_pm_callback(card, suspend, resume, private_data);
871 #endif /* CONFIG_SND_GENERIC_DRIVER */
873 #ifdef CONFIG_PCI
874 int snd_card_pci_suspend(struct pci_dev *dev, pm_message_t state)
876 snd_card_t *card = pci_get_drvdata(dev);
877 int err;
878 if (! card || ! card->pm_suspend)
879 return 0;
880 if (card->power_state == SNDRV_CTL_POWER_D3hot)
881 return 0;
882 err = card->pm_suspend(card, PMSG_SUSPEND);
883 pci_save_state(dev);
884 snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
885 return err;
888 int snd_card_pci_resume(struct pci_dev *dev)
890 snd_card_t *card = pci_get_drvdata(dev);
891 if (! card || ! card->pm_resume)
892 return 0;
893 if (card->power_state == SNDRV_CTL_POWER_D0)
894 return 0;
895 /* restore the PCI config space */
896 pci_restore_state(dev);
897 card->pm_resume(card);
898 snd_power_change_state(card, SNDRV_CTL_POWER_D0);
899 return 0;
901 #endif
903 #endif /* CONFIG_PM */