Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394...
[linux-2.6] / 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 <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>
29
30 #include <sound/core.h>
31 #include <sound/control.h>
32 #include <sound/info.h>
33
34 static DEFINE_SPINLOCK(shutdown_lock);
35 static LIST_HEAD(shutdown_files);
36
37 static const struct file_operations snd_shutdown_f_ops;
38
39 static unsigned int snd_cards_lock;     /* locked for registering/using */
40 struct snd_card *snd_cards[SNDRV_CARDS];
41 EXPORT_SYMBOL(snd_cards);
42
43 static DEFINE_MUTEX(snd_card_mutex);
44
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.");
48
49 /* return non-zero if the given index is already reserved for another
50  * module via slots option
51  */
52 static int module_slot_mismatch(struct module *module, int idx)
53 {
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
62          */
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;
74         }
75 #endif
76         return 0;
77 }
78
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
83
84 #ifdef CONFIG_PROC_FS
85 static void snd_card_id_read(struct snd_info_entry *entry,
86                              struct snd_info_buffer *buffer)
87 {
88         snd_iprintf(buffer, "%s\n", entry->card->id);
89 }
90
91 static inline int init_info_for_card(struct snd_card *card)
92 {
93         int err;
94         struct snd_info_entry *entry;
95
96         if ((err = snd_info_card_register(card)) < 0) {
97                 snd_printd("unable to create card info\n");
98                 return err;
99         }
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;
103         }
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;
108         }
109         card->proc_id = entry;
110         return 0;
111 }
112 #else /* !CONFIG_PROC_FS */
113 #define init_info_for_card(card)
114 #endif
115
116 /**
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
122  *
123  *  Creates and initializes a soundcard structure.
124  *
125  *  Returns kmallocated snd_card structure. Creates the ALSA control interface
126  *  (which is blocked until snd_card_register function is called).
127  */
128 struct snd_card *snd_card_new(int idx, const char *xid,
129                          struct module *module, int extra_size)
130 {
131         struct snd_card *card;
132         int err;
133
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));
143         }
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;
157                         }
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;
167                 }
168         }
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;
174         }
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;
195         }
196         if ((err = snd_info_card_create(card)) < 0) {
197                 snd_printd("unable to create card info\n");
198                 goto __error_ctl;
199         }
200         if (extra_size > 0)
201                 card->private_data = (char *)card + sizeof(struct snd_card);
202         return card;
203
204       __error_ctl:
205         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
206       __error:
207         kfree(card);
208         return NULL;
209 }
210
211 EXPORT_SYMBOL(snd_card_new);
212
213 /* return non-zero if a card is already locked */
214 int snd_card_locked(int card)
215 {
216         int locked;
217
218         mutex_lock(&snd_card_mutex);
219         locked = snd_cards_lock & (1 << card);
220         mutex_unlock(&snd_card_mutex);
221         return locked;
222 }
223
224 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
225 {
226         return -ENODEV;
227 }
228
229 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
230                                    size_t count, loff_t *offset)
231 {
232         return -ENODEV;
233 }
234
235 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
236                                     size_t count, loff_t *offset)
237 {
238         return -ENODEV;
239 }
240
241 static int snd_disconnect_release(struct inode *inode, struct file *file)
242 {
243         struct snd_monitor_file *df = NULL, *_df;
244
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;
250                 }
251         }
252         spin_unlock(&shutdown_lock);
253
254         if (likely(df))
255                 return df->disconnected_f_op->release(inode, file);
256
257         panic("%s(%p, %p) failed!", __func__, inode, file);
258 }
259
260 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
261 {
262         return POLLERR | POLLNVAL;
263 }
264
265 static long snd_disconnect_ioctl(struct file *file,
266                                  unsigned int cmd, unsigned long arg)
267 {
268         return -ENODEV;
269 }
270
271 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
272 {
273         return -ENODEV;
274 }
275
276 static int snd_disconnect_fasync(int fd, struct file *file, int on)
277 {
278         return -ENODEV;
279 }
280
281 static const struct file_operations snd_shutdown_f_ops =
282 {
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
295 };
296
297 /**
298  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
299  *  @card: soundcard structure
300  *
301  *  Disconnects all APIs from the file-operations (user space).
302  *
303  *  Returns zero, otherwise a negative error code.
304  *
305  *  Note: The current implementation replaces all active file->f_op with special
306  *        dummy file operations (they do nothing except release).
307  */
308 int snd_card_disconnect(struct snd_card *card)
309 {
310         struct snd_monitor_file *mfile;
311         struct file *file;
312         int err;
313
314         if (!card)
315                 return -EINVAL;
316
317         spin_lock(&card->files_lock);
318         if (card->shutdown) {
319                 spin_unlock(&card->files_lock);
320                 return 0;
321         }
322         card->shutdown = 1;
323         spin_unlock(&card->files_lock);
324
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);
330         
331         /* phase 2: replace file->f_op with special dummy operations */
332         
333         spin_lock(&card->files_lock);
334         mfile = card->files;
335         while (mfile) {
336                 file = mfile->file;
337
338                 /* it's critical part, use endless loop */
339                 /* we have no room to fail */
340                 mfile->disconnected_f_op = mfile->file->f_op;
341
342                 spin_lock(&shutdown_lock);
343                 list_add(&mfile->shutdown_list, &shutdown_files);
344                 spin_unlock(&shutdown_lock);
345
346                 mfile->file->f_op = &snd_shutdown_f_ops;
347                 fops_get(mfile->file->f_op);
348                 
349                 mfile = mfile->next;
350         }
351         spin_unlock(&card->files_lock); 
352
353         /* phase 3: notify all connected devices about disconnection */
354         /* at this point, they cannot respond to any calls except release() */
355
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
360
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);
365
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;
371         }
372 #endif
373 #ifdef CONFIG_PM
374         wake_up(&card->power_sleep);
375 #endif
376         return 0;       
377 }
378
379 EXPORT_SYMBOL(snd_card_disconnect);
380
381 /**
382  *  snd_card_free - frees given soundcard structure
383  *  @card: soundcard structure
384  *
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.
388  *
389  *  Returns zero. Frees all associated devices and frees the control
390  *  interface associated to given soundcard.
391  */
392 static int snd_card_do_free(struct snd_card *card)
393 {
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 */
401         }
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 */
405         }
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 */
409         }
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 */
416         }
417         kfree(card);
418         return 0;
419 }
420
421 int snd_card_free_when_closed(struct snd_card *card)
422 {
423         int free_now = 0;
424         int ret = snd_card_disconnect(card);
425         if (ret)
426                 return ret;
427
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);
434
435         if (free_now)
436                 snd_card_do_free(card);
437         return 0;
438 }
439
440 EXPORT_SYMBOL(snd_card_free_when_closed);
441
442 int snd_card_free(struct snd_card *card)
443 {
444         int ret = snd_card_disconnect(card);
445         if (ret)
446                 return ret;
447
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;
452 }
453
454 EXPORT_SYMBOL(snd_card_free);
455
456 static void choose_default_id(struct snd_card *card)
457 {
458         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
459         char *id, *spos;
460         
461         id = spos = card->shortname;    
462         while (*id != '\0') {
463                 if (*id == ' ')
464                         spos = id + 1;
465                 id++;
466         }
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++;
476         }
477         *id = '\0';
478
479         id = card->id;
480         
481         if (*id == '\0')
482                 strcpy(id, "default");
483
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;
489                 }
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;
495                 }
496                 break;
497
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++;
516                 }
517         }
518 }
519
520 /**
521  *  snd_card_register - register the soundcard
522  *  @card: soundcard structure
523  *
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.
528  *
529  *  Returns zero otherwise a negative error code if the registrain failed.
530  */
531 int snd_card_register(struct snd_card *card)
532 {
533         int err;
534
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;
542         }
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;
551         }
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;
562 }
563
564 EXPORT_SYMBOL(snd_card_register);
565
566 #ifdef CONFIG_PROC_FS
567 static struct snd_info_entry *snd_card_info_entry;
568
569 static void snd_card_info_read(struct snd_info_entry *entry,
570                                struct snd_info_buffer *buffer)
571 {
572         int idx, count;
573         struct snd_card *card;
574
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);
586                 }
587                 mutex_unlock(&snd_card_mutex);
588         }
589         if (!count)
590                 snd_iprintf(buffer, "--- no soundcards ---\n");
591 }
592
593 #ifdef CONFIG_SND_OSSEMUL
594
595 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
596 {
597         int idx, count;
598         struct snd_card *card;
599
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);
605                 }
606                 mutex_unlock(&snd_card_mutex);
607         }
608         if (!count) {
609                 snd_iprintf(buffer, "--- no soundcards ---\n");
610         }
611 }
612
613 #endif
614
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)
619 {
620         int idx;
621         struct snd_card *card;
622
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);
629         }
630 }
631 #endif
632
633 int __init snd_card_info_init(void)
634 {
635         struct snd_info_entry *entry;
636
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;
644         }
645         snd_card_info_entry = entry;
646
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;
655         }
656 #endif
657
658         return 0;
659 }
660
661 int __exit snd_card_info_done(void)
662 {
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;
668 }
669
670 #endif /* CONFIG_PROC_FS */
671
672 /**
673  *  snd_component_add - add a component string
674  *  @card: soundcard structure
675  *  @component: the component id string
676  *
677  *  This function adds the component id string to the supported list.
678  *  The component can be referred from the alsa-lib.
679  *
680  *  Returns zero otherwise a negative error code.
681  */
682   
683 int snd_component_add(struct snd_card *card, const char *component)
684 {
685         char *ptr;
686         int len = strlen(component);
687
688         ptr = strstr(card->components, component);
689         if (ptr != NULL) {
690                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
691                         return 1;
692         }
693         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
694                 snd_BUG();
695                 return -ENOMEM;
696         }
697         if (card->components[0] != '\0')
698                 strcat(card->components, " ");
699         strcat(card->components, component);
700         return 0;
701 }
702
703 EXPORT_SYMBOL(snd_component_add);
704
705 /**
706  *  snd_card_file_add - add the file to the file list of the card
707  *  @card: soundcard structure
708  *  @file: file pointer
709  *
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.
713  *
714  *  Returns zero or a negative error code.
715  */
716 int snd_card_file_add(struct snd_card *card, struct file *file)
717 {
718         struct snd_monitor_file *mfile;
719
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;
731         }
732         mfile->next = card->files;
733         card->files = mfile;
734         spin_unlock(&card->files_lock);
735         return 0;
736 }
737
738 EXPORT_SYMBOL(snd_card_file_add);
739
740 /**
741  *  snd_card_file_remove - remove the file from the file list
742  *  @card: soundcard structure
743  *  @file: file pointer
744  *
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.
750  *
751  *  Returns zero or a negative error code.
752  */
753 int snd_card_file_remove(struct snd_card *card, struct file *file)
754 {
755         struct snd_monitor_file *mfile, *pfile = NULL;
756         int last_close = 0;
757
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;
767                 }
768                 pfile = mfile;
769                 mfile = mfile->next;
770         }
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);
776         }
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);
784         }
785         if (!mfile) {
786                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
787                 return -ENOENT;
788         }
789         kfree(mfile);
790         return 0;
791 }
792
793 EXPORT_SYMBOL(snd_card_file_remove);
794
795 #ifdef CONFIG_PM
796 /**
797  *  snd_power_wait - wait until the power-state is changed.
798  *  @card: soundcard structure
799  *  @power_state: expected power state
800  *
801  *  Waits until the power-state is changed.
802  *
803  *  Note: the power lock must be active before call.
804  */
805 int snd_power_wait(struct snd_card *card, unsigned int power_state)
806 {
807         wait_queue_t wait;
808         int result = 0;
809
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;
819                 }
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);
826         }
827         remove_wait_queue(&card->power_sleep, &wait);
828         return result;
829 }
830
831 EXPORT_SYMBOL(snd_power_wait);
832 #endif /* CONFIG_PM */