[ALSA] Changed Jaroslav Kysela's e-mail from perex@suse.cz to perex@perex.cz
[linux-2.6.git] / sound / core / init.c
1 /*
2  *  Initialization routines
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
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.
10  *
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.
15  *
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
19  *
20  */
21
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/pm.h>
30
31 #include <sound/core.h>
32 #include <sound/control.h>
33 #include <sound/info.h>
34
35 static DEFINE_SPINLOCK(shutdown_lock);
36 static LIST_HEAD(shutdown_files);
37
38 static const struct file_operations snd_shutdown_f_ops;
39
40 static unsigned int snd_cards_lock;     /* locked for registering/using */
41 struct snd_card *snd_cards[SNDRV_CARDS];
42 EXPORT_SYMBOL(snd_cards);
43
44 static DEFINE_MUTEX(snd_card_mutex);
45
46 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
47 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
48 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
49 #endif
50
51 #ifdef CONFIG_PROC_FS
52 static void snd_card_id_read(struct snd_info_entry *entry,
53                              struct snd_info_buffer *buffer)
54 {
55         snd_iprintf(buffer, "%s\n", entry->card->id);
56 }
57
58 static inline int init_info_for_card(struct snd_card *card)
59 {
60         int err;
61         struct snd_info_entry *entry;
62
63         if ((err = snd_info_card_register(card)) < 0) {
64                 snd_printd("unable to create card info\n");
65                 return err;
66         }
67         if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
68                 snd_printd("unable to create card entry\n");
69                 return err;
70         }
71         entry->c.text.read = snd_card_id_read;
72         if (snd_info_register(entry) < 0) {
73                 snd_info_free_entry(entry);
74                 entry = NULL;
75         }
76         card->proc_id = entry;
77         return 0;
78 }
79 #else /* !CONFIG_PROC_FS */
80 #define init_info_for_card(card)
81 #endif
82
83 /**
84  *  snd_card_new - create and initialize a soundcard structure
85  *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
86  *  @xid: card identification (ASCII string)
87  *  @module: top level module for locking
88  *  @extra_size: allocate this extra size after the main soundcard structure
89  *
90  *  Creates and initializes a soundcard structure.
91  *
92  *  Returns kmallocated snd_card structure. Creates the ALSA control interface
93  *  (which is blocked until snd_card_register function is called).
94  */
95 struct snd_card *snd_card_new(int idx, const char *xid,
96                          struct module *module, int extra_size)
97 {
98         struct snd_card *card;
99         int err;
100
101         if (extra_size < 0)
102                 extra_size = 0;
103         card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
104         if (card == NULL)
105                 return NULL;
106         if (xid) {
107                 if (!snd_info_check_reserved_words(xid))
108                         goto __error;
109                 strlcpy(card->id, xid, sizeof(card->id));
110         }
111         err = 0;
112         mutex_lock(&snd_card_mutex);
113         if (idx < 0) {
114                 int idx2;
115                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
116                         /* idx == -1 == 0xffff means: take any free slot */
117                         if (~snd_cards_lock & idx & 1<<idx2) {
118                                 idx = idx2;
119                                 if (idx >= snd_ecards_limit)
120                                         snd_ecards_limit = idx + 1;
121                                 break;
122                         }
123         } else {
124                  if (idx < snd_ecards_limit) {
125                         if (snd_cards_lock & (1 << idx))
126                                 err = -EBUSY;   /* invalid */
127                 } else {
128                         if (idx < SNDRV_CARDS)
129                                 snd_ecards_limit = idx + 1; /* increase the limit */
130                         else
131                                 err = -ENODEV;
132                 }
133         }
134         if (idx < 0 || err < 0) {
135                 mutex_unlock(&snd_card_mutex);
136                 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
137                          idx, snd_ecards_limit - 1, err);
138                 goto __error;
139         }
140         snd_cards_lock |= 1 << idx;             /* lock it */
141         mutex_unlock(&snd_card_mutex);
142         card->number = idx;
143         card->module = module;
144         INIT_LIST_HEAD(&card->devices);
145         init_rwsem(&card->controls_rwsem);
146         rwlock_init(&card->ctl_files_rwlock);
147         INIT_LIST_HEAD(&card->controls);
148         INIT_LIST_HEAD(&card->ctl_files);
149         spin_lock_init(&card->files_lock);
150         init_waitqueue_head(&card->shutdown_sleep);
151 #ifdef CONFIG_PM
152         mutex_init(&card->power_lock);
153         init_waitqueue_head(&card->power_sleep);
154 #endif
155         /* the control interface cannot be accessed from the user space until */
156         /* snd_cards_bitmask and snd_cards are set with snd_card_register */
157         if ((err = snd_ctl_create(card)) < 0) {
158                 snd_printd("unable to register control minors\n");
159                 goto __error;
160         }
161         if ((err = snd_info_card_create(card)) < 0) {
162                 snd_printd("unable to create card info\n");
163                 goto __error_ctl;
164         }
165         if (extra_size > 0)
166                 card->private_data = (char *)card + sizeof(struct snd_card);
167         return card;
168
169       __error_ctl:
170         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
171       __error:
172         kfree(card);
173         return NULL;
174 }
175
176 EXPORT_SYMBOL(snd_card_new);
177
178 /* return non-zero if a card is already locked */
179 int snd_card_locked(int card)
180 {
181         int locked;
182
183         mutex_lock(&snd_card_mutex);
184         locked = snd_cards_lock & (1 << card);
185         mutex_unlock(&snd_card_mutex);
186         return locked;
187 }
188
189 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
190 {
191         return -ENODEV;
192 }
193
194 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
195                                    size_t count, loff_t *offset)
196 {
197         return -ENODEV;
198 }
199
200 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
201                                     size_t count, loff_t *offset)
202 {
203         return -ENODEV;
204 }
205
206 static int snd_disconnect_release(struct inode *inode, struct file *file)
207 {
208         struct snd_monitor_file *df = NULL, *_df;
209
210         spin_lock(&shutdown_lock);
211         list_for_each_entry(_df, &shutdown_files, shutdown_list) {
212                 if (_df->file == file) {
213                         df = _df;
214                         break;
215                 }
216         }
217         spin_unlock(&shutdown_lock);
218
219         if (likely(df))
220                 return df->disconnected_f_op->release(inode, file);
221
222         panic("%s(%p, %p) failed!", __FUNCTION__, inode, file);
223 }
224
225 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
226 {
227         return POLLERR | POLLNVAL;
228 }
229
230 static long snd_disconnect_ioctl(struct file *file,
231                                  unsigned int cmd, unsigned long arg)
232 {
233         return -ENODEV;
234 }
235
236 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
237 {
238         return -ENODEV;
239 }
240
241 static int snd_disconnect_fasync(int fd, struct file *file, int on)
242 {
243         return -ENODEV;
244 }
245
246 static const struct file_operations snd_shutdown_f_ops =
247 {
248         .owner =        THIS_MODULE,
249         .llseek =       snd_disconnect_llseek,
250         .read =         snd_disconnect_read,
251         .write =        snd_disconnect_write,
252         .release =      snd_disconnect_release,
253         .poll =         snd_disconnect_poll,
254         .unlocked_ioctl = snd_disconnect_ioctl,
255 #ifdef CONFIG_COMPAT
256         .compat_ioctl = snd_disconnect_ioctl,
257 #endif
258         .mmap =         snd_disconnect_mmap,
259         .fasync =       snd_disconnect_fasync
260 };
261
262 /**
263  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
264  *  @card: soundcard structure
265  *
266  *  Disconnects all APIs from the file-operations (user space).
267  *
268  *  Returns zero, otherwise a negative error code.
269  *
270  *  Note: The current implementation replaces all active file->f_op with special
271  *        dummy file operations (they do nothing except release).
272  */
273 int snd_card_disconnect(struct snd_card *card)
274 {
275         struct snd_monitor_file *mfile;
276         struct file *file;
277         int err;
278
279         spin_lock(&card->files_lock);
280         if (card->shutdown) {
281                 spin_unlock(&card->files_lock);
282                 return 0;
283         }
284         card->shutdown = 1;
285         spin_unlock(&card->files_lock);
286
287         /* phase 1: disable fops (user space) operations for ALSA API */
288         mutex_lock(&snd_card_mutex);
289         snd_cards[card->number] = NULL;
290         mutex_unlock(&snd_card_mutex);
291         
292         /* phase 2: replace file->f_op with special dummy operations */
293         
294         spin_lock(&card->files_lock);
295         mfile = card->files;
296         while (mfile) {
297                 file = mfile->file;
298
299                 /* it's critical part, use endless loop */
300                 /* we have no room to fail */
301                 mfile->disconnected_f_op = mfile->file->f_op;
302
303                 spin_lock(&shutdown_lock);
304                 list_add(&mfile->shutdown_list, &shutdown_files);
305                 spin_unlock(&shutdown_lock);
306
307                 fops_get(&snd_shutdown_f_ops);
308                 mfile->file->f_op = &snd_shutdown_f_ops;
309                 
310                 mfile = mfile->next;
311         }
312         spin_unlock(&card->files_lock); 
313
314         /* phase 3: notify all connected devices about disconnection */
315         /* at this point, they cannot respond to any calls except release() */
316
317 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
318         if (snd_mixer_oss_notify_callback)
319                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
320 #endif
321
322         /* notify all devices that we are disconnected */
323         err = snd_device_disconnect_all(card);
324         if (err < 0)
325                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
326
327         snd_info_card_disconnect(card);
328         return 0;       
329 }
330
331 EXPORT_SYMBOL(snd_card_disconnect);
332
333 /**
334  *  snd_card_free - frees given soundcard structure
335  *  @card: soundcard structure
336  *
337  *  This function releases the soundcard structure and the all assigned
338  *  devices automatically.  That is, you don't have to release the devices
339  *  by yourself.
340  *
341  *  Returns zero. Frees all associated devices and frees the control
342  *  interface associated to given soundcard.
343  */
344 static int snd_card_do_free(struct snd_card *card)
345 {
346 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
347         if (snd_mixer_oss_notify_callback)
348                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
349 #endif
350         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
351                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
352                 /* Fatal, but this situation should never occur */
353         }
354         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
355                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
356                 /* Fatal, but this situation should never occur */
357         }
358         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
359                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
360                 /* Fatal, but this situation should never occur */
361         }
362         if (card->private_free)
363                 card->private_free(card);
364         snd_info_free_entry(card->proc_id);
365         if (snd_info_card_free(card) < 0) {
366                 snd_printk(KERN_WARNING "unable to free card info\n");
367                 /* Not fatal error */
368         }
369 #ifndef CONFIG_SYSFS_DEPRECATED
370         if (card->card_dev)
371                 device_unregister(card->card_dev);
372 #endif
373         kfree(card);
374         return 0;
375 }
376
377 static int snd_card_free_prepare(struct snd_card *card)
378 {
379         if (card == NULL)
380                 return -EINVAL;
381         (void) snd_card_disconnect(card);
382         mutex_lock(&snd_card_mutex);
383         snd_cards[card->number] = NULL;
384         snd_cards_lock &= ~(1 << card->number);
385         mutex_unlock(&snd_card_mutex);
386 #ifdef CONFIG_PM
387         wake_up(&card->power_sleep);
388 #endif
389         return 0;
390 }
391
392 int snd_card_free_when_closed(struct snd_card *card)
393 {
394         int free_now = 0;
395         int ret = snd_card_free_prepare(card);
396         if (ret)
397                 return ret;
398
399         spin_lock(&card->files_lock);
400         if (card->files == NULL)
401                 free_now = 1;
402         else
403                 card->free_on_last_close = 1;
404         spin_unlock(&card->files_lock);
405
406         if (free_now)
407                 snd_card_do_free(card);
408         return 0;
409 }
410
411 EXPORT_SYMBOL(snd_card_free_when_closed);
412
413 int snd_card_free(struct snd_card *card)
414 {
415         int ret = snd_card_free_prepare(card);
416         if (ret)
417                 return ret;
418
419         /* wait, until all devices are ready for the free operation */
420         wait_event(card->shutdown_sleep, card->files == NULL);
421         snd_card_do_free(card);
422         return 0;
423 }
424
425 EXPORT_SYMBOL(snd_card_free);
426
427 static void choose_default_id(struct snd_card *card)
428 {
429         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
430         char *id, *spos;
431         
432         id = spos = card->shortname;    
433         while (*id != '\0') {
434                 if (*id == ' ')
435                         spos = id + 1;
436                 id++;
437         }
438         id = card->id;
439         while (*spos != '\0' && !isalnum(*spos))
440                 spos++;
441         if (isdigit(*spos))
442                 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
443         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
444                 if (isalnum(*spos))
445                         *id++ = *spos;
446                 spos++;
447         }
448         *id = '\0';
449
450         id = card->id;
451         
452         if (*id == '\0')
453                 strcpy(id, "default");
454
455         while (1) {
456                 if (loops-- == 0) {
457                         snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
458                         strcpy(card->id, card->proc_root->name);
459                         return;
460                 }
461                 if (!snd_info_check_reserved_words(id))
462                         goto __change;
463                 for (i = 0; i < snd_ecards_limit; i++) {
464                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
465                                 goto __change;
466                 }
467                 break;
468
469               __change:
470                 len = strlen(id);
471                 if (idx_flag) {
472                         if (id[len-1] != '9')
473                                 id[len-1]++;
474                         else
475                                 id[len-1] = 'A';
476                 } else if ((size_t)len <= sizeof(card->id) - 3) {
477                         strcat(id, "_1");
478                         idx_flag++;
479                 } else {
480                         spos = id + len - 2;
481                         if ((size_t)len <= sizeof(card->id) - 2)
482                                 spos++;
483                         *spos++ = '_';
484                         *spos++ = '1';
485                         *spos++ = '\0';
486                         idx_flag++;
487                 }
488         }
489 }
490
491 /**
492  *  snd_card_register - register the soundcard
493  *  @card: soundcard structure
494  *
495  *  This function registers all the devices assigned to the soundcard.
496  *  Until calling this, the ALSA control interface is blocked from the
497  *  external accesses.  Thus, you should call this function at the end
498  *  of the initialization of the card.
499  *
500  *  Returns zero otherwise a negative error code if the registrain failed.
501  */
502 int snd_card_register(struct snd_card *card)
503 {
504         int err;
505
506         snd_assert(card != NULL, return -EINVAL);
507 #ifndef CONFIG_SYSFS_DEPRECATED
508         if (!card->card_dev) {
509                 card->card_dev = device_create(sound_class, card->dev, 0,
510                                                "card%i", card->number);
511                 if (IS_ERR(card->card_dev))
512                         card->card_dev = NULL;
513         }
514 #endif
515         if ((err = snd_device_register_all(card)) < 0)
516                 return err;
517         mutex_lock(&snd_card_mutex);
518         if (snd_cards[card->number]) {
519                 /* already registered */
520                 mutex_unlock(&snd_card_mutex);
521                 return 0;
522         }
523         if (card->id[0] == '\0')
524                 choose_default_id(card);
525         snd_cards[card->number] = card;
526         mutex_unlock(&snd_card_mutex);
527         init_info_for_card(card);
528 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
529         if (snd_mixer_oss_notify_callback)
530                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
531 #endif
532         return 0;
533 }
534
535 EXPORT_SYMBOL(snd_card_register);
536
537 #ifdef CONFIG_PROC_FS
538 static struct snd_info_entry *snd_card_info_entry;
539
540 static void snd_card_info_read(struct snd_info_entry *entry,
541                                struct snd_info_buffer *buffer)
542 {
543         int idx, count;
544         struct snd_card *card;
545
546         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
547                 mutex_lock(&snd_card_mutex);
548                 if ((card = snd_cards[idx]) != NULL) {
549                         count++;
550                         snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
551                                         idx,
552                                         card->id,
553                                         card->driver,
554                                         card->shortname);
555                         snd_iprintf(buffer, "                      %s\n",
556                                         card->longname);
557                 }
558                 mutex_unlock(&snd_card_mutex);
559         }
560         if (!count)
561                 snd_iprintf(buffer, "--- no soundcards ---\n");
562 }
563
564 #ifdef CONFIG_SND_OSSEMUL
565
566 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
567 {
568         int idx, count;
569         struct snd_card *card;
570
571         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
572                 mutex_lock(&snd_card_mutex);
573                 if ((card = snd_cards[idx]) != NULL) {
574                         count++;
575                         snd_iprintf(buffer, "%s\n", card->longname);
576                 }
577                 mutex_unlock(&snd_card_mutex);
578         }
579         if (!count) {
580                 snd_iprintf(buffer, "--- no soundcards ---\n");
581         }
582 }
583
584 #endif
585
586 #ifdef MODULE
587 static struct snd_info_entry *snd_card_module_info_entry;
588 static void snd_card_module_info_read(struct snd_info_entry *entry,
589                                       struct snd_info_buffer *buffer)
590 {
591         int idx;
592         struct snd_card *card;
593
594         for (idx = 0; idx < SNDRV_CARDS; idx++) {
595                 mutex_lock(&snd_card_mutex);
596                 if ((card = snd_cards[idx]) != NULL)
597                         snd_iprintf(buffer, "%2i %s\n",
598                                     idx, card->module->name);
599                 mutex_unlock(&snd_card_mutex);
600         }
601 }
602 #endif
603
604 int __init snd_card_info_init(void)
605 {
606         struct snd_info_entry *entry;
607
608         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
609         if (! entry)
610                 return -ENOMEM;
611         entry->c.text.read = snd_card_info_read;
612         if (snd_info_register(entry) < 0) {
613                 snd_info_free_entry(entry);
614                 return -ENOMEM;
615         }
616         snd_card_info_entry = entry;
617
618 #ifdef MODULE
619         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
620         if (entry) {
621                 entry->c.text.read = snd_card_module_info_read;
622                 if (snd_info_register(entry) < 0)
623                         snd_info_free_entry(entry);
624                 else
625                         snd_card_module_info_entry = entry;
626         }
627 #endif
628
629         return 0;
630 }
631
632 int __exit snd_card_info_done(void)
633 {
634         snd_info_free_entry(snd_card_info_entry);
635 #ifdef MODULE
636         snd_info_free_entry(snd_card_module_info_entry);
637 #endif
638         return 0;
639 }
640
641 #endif /* CONFIG_PROC_FS */
642
643 /**
644  *  snd_component_add - add a component string
645  *  @card: soundcard structure
646  *  @component: the component id string
647  *
648  *  This function adds the component id string to the supported list.
649  *  The component can be referred from the alsa-lib.
650  *
651  *  Returns zero otherwise a negative error code.
652  */
653   
654 int snd_component_add(struct snd_card *card, const char *component)
655 {
656         char *ptr;
657         int len = strlen(component);
658
659         ptr = strstr(card->components, component);
660         if (ptr != NULL) {
661                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
662                         return 1;
663         }
664         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
665                 snd_BUG();
666                 return -ENOMEM;
667         }
668         if (card->components[0] != '\0')
669                 strcat(card->components, " ");
670         strcat(card->components, component);
671         return 0;
672 }
673
674 EXPORT_SYMBOL(snd_component_add);
675
676 /**
677  *  snd_card_file_add - add the file to the file list of the card
678  *  @card: soundcard structure
679  *  @file: file pointer
680  *
681  *  This function adds the file to the file linked-list of the card.
682  *  This linked-list is used to keep tracking the connection state,
683  *  and to avoid the release of busy resources by hotplug.
684  *
685  *  Returns zero or a negative error code.
686  */
687 int snd_card_file_add(struct snd_card *card, struct file *file)
688 {
689         struct snd_monitor_file *mfile;
690
691         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
692         if (mfile == NULL)
693                 return -ENOMEM;
694         mfile->file = file;
695         mfile->disconnected_f_op = NULL;
696         mfile->next = NULL;
697         spin_lock(&card->files_lock);
698         if (card->shutdown) {
699                 spin_unlock(&card->files_lock);
700                 kfree(mfile);
701                 return -ENODEV;
702         }
703         mfile->next = card->files;
704         card->files = mfile;
705         spin_unlock(&card->files_lock);
706         return 0;
707 }
708
709 EXPORT_SYMBOL(snd_card_file_add);
710
711 /**
712  *  snd_card_file_remove - remove the file from the file list
713  *  @card: soundcard structure
714  *  @file: file pointer
715  *
716  *  This function removes the file formerly added to the card via
717  *  snd_card_file_add() function.
718  *  If all files are removed and snd_card_free_when_closed() was
719  *  called beforehand, it processes the pending release of
720  *  resources.
721  *
722  *  Returns zero or a negative error code.
723  */
724 int snd_card_file_remove(struct snd_card *card, struct file *file)
725 {
726         struct snd_monitor_file *mfile, *pfile = NULL;
727         int last_close = 0;
728
729         spin_lock(&card->files_lock);
730         mfile = card->files;
731         while (mfile) {
732                 if (mfile->file == file) {
733                         if (pfile)
734                                 pfile->next = mfile->next;
735                         else
736                                 card->files = mfile->next;
737                         break;
738                 }
739                 pfile = mfile;
740                 mfile = mfile->next;
741         }
742         if (mfile && mfile->disconnected_f_op) {
743                 fops_put(mfile->disconnected_f_op);
744                 spin_lock(&shutdown_lock);
745                 list_del(&mfile->shutdown_list);
746                 spin_unlock(&shutdown_lock);
747         }
748         if (card->files == NULL)
749                 last_close = 1;
750         spin_unlock(&card->files_lock);
751         if (last_close) {
752                 wake_up(&card->shutdown_sleep);
753                 if (card->free_on_last_close)
754                         snd_card_do_free(card);
755         }
756         if (!mfile) {
757                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
758                 return -ENOENT;
759         }
760         kfree(mfile);
761         return 0;
762 }
763
764 EXPORT_SYMBOL(snd_card_file_remove);
765
766 #ifdef CONFIG_PM
767 /**
768  *  snd_power_wait - wait until the power-state is changed.
769  *  @card: soundcard structure
770  *  @power_state: expected power state
771  *
772  *  Waits until the power-state is changed.
773  *
774  *  Note: the power lock must be active before call.
775  */
776 int snd_power_wait(struct snd_card *card, unsigned int power_state)
777 {
778         wait_queue_t wait;
779         int result = 0;
780
781         /* fastpath */
782         if (snd_power_get_state(card) == power_state)
783                 return 0;
784         init_waitqueue_entry(&wait, current);
785         add_wait_queue(&card->power_sleep, &wait);
786         while (1) {
787                 if (card->shutdown) {
788                         result = -ENODEV;
789                         break;
790                 }
791                 if (snd_power_get_state(card) == power_state)
792                         break;
793                 set_current_state(TASK_UNINTERRUPTIBLE);
794                 snd_power_unlock(card);
795                 schedule_timeout(30 * HZ);
796                 snd_power_lock(card);
797         }
798         remove_wait_queue(&card->power_sleep, &wait);
799         return result;
800 }
801
802 EXPORT_SYMBOL(snd_power_wait);
803 #endif /* CONFIG_PM */