[ALSA] Remove sound/driver.h
[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 <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!", __FUNCTION__, 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         spin_lock(&card->files_lock);
315         if (card->shutdown) {
316                 spin_unlock(&card->files_lock);
317                 return 0;
318         }
319         card->shutdown = 1;
320         spin_unlock(&card->files_lock);
321
322         /* phase 1: disable fops (user space) operations for ALSA API */
323         mutex_lock(&snd_card_mutex);
324         snd_cards[card->number] = NULL;
325         mutex_unlock(&snd_card_mutex);
326         
327         /* phase 2: replace file->f_op with special dummy operations */
328         
329         spin_lock(&card->files_lock);
330         mfile = card->files;
331         while (mfile) {
332                 file = mfile->file;
333
334                 /* it's critical part, use endless loop */
335                 /* we have no room to fail */
336                 mfile->disconnected_f_op = mfile->file->f_op;
337
338                 spin_lock(&shutdown_lock);
339                 list_add(&mfile->shutdown_list, &shutdown_files);
340                 spin_unlock(&shutdown_lock);
341
342                 fops_get(&snd_shutdown_f_ops);
343                 mfile->file->f_op = &snd_shutdown_f_ops;
344                 
345                 mfile = mfile->next;
346         }
347         spin_unlock(&card->files_lock); 
348
349         /* phase 3: notify all connected devices about disconnection */
350         /* at this point, they cannot respond to any calls except release() */
351
352 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
353         if (snd_mixer_oss_notify_callback)
354                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
355 #endif
356
357         /* notify all devices that we are disconnected */
358         err = snd_device_disconnect_all(card);
359         if (err < 0)
360                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
361
362         snd_info_card_disconnect(card);
363         return 0;       
364 }
365
366 EXPORT_SYMBOL(snd_card_disconnect);
367
368 /**
369  *  snd_card_free - frees given soundcard structure
370  *  @card: soundcard structure
371  *
372  *  This function releases the soundcard structure and the all assigned
373  *  devices automatically.  That is, you don't have to release the devices
374  *  by yourself.
375  *
376  *  Returns zero. Frees all associated devices and frees the control
377  *  interface associated to given soundcard.
378  */
379 static int snd_card_do_free(struct snd_card *card)
380 {
381 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
382         if (snd_mixer_oss_notify_callback)
383                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
384 #endif
385         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
386                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
387                 /* Fatal, but this situation should never occur */
388         }
389         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
390                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
391                 /* Fatal, but this situation should never occur */
392         }
393         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
394                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
395                 /* Fatal, but this situation should never occur */
396         }
397         if (card->private_free)
398                 card->private_free(card);
399         snd_info_free_entry(card->proc_id);
400         if (snd_info_card_free(card) < 0) {
401                 snd_printk(KERN_WARNING "unable to free card info\n");
402                 /* Not fatal error */
403         }
404 #ifndef CONFIG_SYSFS_DEPRECATED
405         if (card->card_dev)
406                 device_unregister(card->card_dev);
407 #endif
408         kfree(card);
409         return 0;
410 }
411
412 static int snd_card_free_prepare(struct snd_card *card)
413 {
414         if (card == NULL)
415                 return -EINVAL;
416         (void) snd_card_disconnect(card);
417         mutex_lock(&snd_card_mutex);
418         snd_cards[card->number] = NULL;
419         snd_cards_lock &= ~(1 << card->number);
420         mutex_unlock(&snd_card_mutex);
421 #ifdef CONFIG_PM
422         wake_up(&card->power_sleep);
423 #endif
424         return 0;
425 }
426
427 int snd_card_free_when_closed(struct snd_card *card)
428 {
429         int free_now = 0;
430         int ret = snd_card_free_prepare(card);
431         if (ret)
432                 return ret;
433
434         spin_lock(&card->files_lock);
435         if (card->files == NULL)
436                 free_now = 1;
437         else
438                 card->free_on_last_close = 1;
439         spin_unlock(&card->files_lock);
440
441         if (free_now)
442                 snd_card_do_free(card);
443         return 0;
444 }
445
446 EXPORT_SYMBOL(snd_card_free_when_closed);
447
448 int snd_card_free(struct snd_card *card)
449 {
450         int ret = snd_card_free_prepare(card);
451         if (ret)
452                 return ret;
453
454         /* wait, until all devices are ready for the free operation */
455         wait_event(card->shutdown_sleep, card->files == NULL);
456         snd_card_do_free(card);
457         return 0;
458 }
459
460 EXPORT_SYMBOL(snd_card_free);
461
462 static void choose_default_id(struct snd_card *card)
463 {
464         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
465         char *id, *spos;
466         
467         id = spos = card->shortname;    
468         while (*id != '\0') {
469                 if (*id == ' ')
470                         spos = id + 1;
471                 id++;
472         }
473         id = card->id;
474         while (*spos != '\0' && !isalnum(*spos))
475                 spos++;
476         if (isdigit(*spos))
477                 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
478         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
479                 if (isalnum(*spos))
480                         *id++ = *spos;
481                 spos++;
482         }
483         *id = '\0';
484
485         id = card->id;
486         
487         if (*id == '\0')
488                 strcpy(id, "default");
489
490         while (1) {
491                 if (loops-- == 0) {
492                         snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
493                         strcpy(card->id, card->proc_root->name);
494                         return;
495                 }
496                 if (!snd_info_check_reserved_words(id))
497                         goto __change;
498                 for (i = 0; i < snd_ecards_limit; i++) {
499                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
500                                 goto __change;
501                 }
502                 break;
503
504               __change:
505                 len = strlen(id);
506                 if (idx_flag) {
507                         if (id[len-1] != '9')
508                                 id[len-1]++;
509                         else
510                                 id[len-1] = 'A';
511                 } else if ((size_t)len <= sizeof(card->id) - 3) {
512                         strcat(id, "_1");
513                         idx_flag++;
514                 } else {
515                         spos = id + len - 2;
516                         if ((size_t)len <= sizeof(card->id) - 2)
517                                 spos++;
518                         *spos++ = '_';
519                         *spos++ = '1';
520                         *spos++ = '\0';
521                         idx_flag++;
522                 }
523         }
524 }
525
526 /**
527  *  snd_card_register - register the soundcard
528  *  @card: soundcard structure
529  *
530  *  This function registers all the devices assigned to the soundcard.
531  *  Until calling this, the ALSA control interface is blocked from the
532  *  external accesses.  Thus, you should call this function at the end
533  *  of the initialization of the card.
534  *
535  *  Returns zero otherwise a negative error code if the registrain failed.
536  */
537 int snd_card_register(struct snd_card *card)
538 {
539         int err;
540
541         snd_assert(card != NULL, return -EINVAL);
542 #ifndef CONFIG_SYSFS_DEPRECATED
543         if (!card->card_dev) {
544                 card->card_dev = device_create(sound_class, card->dev, 0,
545                                                "card%i", card->number);
546                 if (IS_ERR(card->card_dev))
547                         card->card_dev = NULL;
548         }
549 #endif
550         if ((err = snd_device_register_all(card)) < 0)
551                 return err;
552         mutex_lock(&snd_card_mutex);
553         if (snd_cards[card->number]) {
554                 /* already registered */
555                 mutex_unlock(&snd_card_mutex);
556                 return 0;
557         }
558         if (card->id[0] == '\0')
559                 choose_default_id(card);
560         snd_cards[card->number] = card;
561         mutex_unlock(&snd_card_mutex);
562         init_info_for_card(card);
563 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
564         if (snd_mixer_oss_notify_callback)
565                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
566 #endif
567         return 0;
568 }
569
570 EXPORT_SYMBOL(snd_card_register);
571
572 #ifdef CONFIG_PROC_FS
573 static struct snd_info_entry *snd_card_info_entry;
574
575 static void snd_card_info_read(struct snd_info_entry *entry,
576                                struct snd_info_buffer *buffer)
577 {
578         int idx, count;
579         struct snd_card *card;
580
581         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
582                 mutex_lock(&snd_card_mutex);
583                 if ((card = snd_cards[idx]) != NULL) {
584                         count++;
585                         snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
586                                         idx,
587                                         card->id,
588                                         card->driver,
589                                         card->shortname);
590                         snd_iprintf(buffer, "                      %s\n",
591                                         card->longname);
592                 }
593                 mutex_unlock(&snd_card_mutex);
594         }
595         if (!count)
596                 snd_iprintf(buffer, "--- no soundcards ---\n");
597 }
598
599 #ifdef CONFIG_SND_OSSEMUL
600
601 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
602 {
603         int idx, count;
604         struct snd_card *card;
605
606         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
607                 mutex_lock(&snd_card_mutex);
608                 if ((card = snd_cards[idx]) != NULL) {
609                         count++;
610                         snd_iprintf(buffer, "%s\n", card->longname);
611                 }
612                 mutex_unlock(&snd_card_mutex);
613         }
614         if (!count) {
615                 snd_iprintf(buffer, "--- no soundcards ---\n");
616         }
617 }
618
619 #endif
620
621 #ifdef MODULE
622 static struct snd_info_entry *snd_card_module_info_entry;
623 static void snd_card_module_info_read(struct snd_info_entry *entry,
624                                       struct snd_info_buffer *buffer)
625 {
626         int idx;
627         struct snd_card *card;
628
629         for (idx = 0; idx < SNDRV_CARDS; idx++) {
630                 mutex_lock(&snd_card_mutex);
631                 if ((card = snd_cards[idx]) != NULL)
632                         snd_iprintf(buffer, "%2i %s\n",
633                                     idx, card->module->name);
634                 mutex_unlock(&snd_card_mutex);
635         }
636 }
637 #endif
638
639 int __init snd_card_info_init(void)
640 {
641         struct snd_info_entry *entry;
642
643         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
644         if (! entry)
645                 return -ENOMEM;
646         entry->c.text.read = snd_card_info_read;
647         if (snd_info_register(entry) < 0) {
648                 snd_info_free_entry(entry);
649                 return -ENOMEM;
650         }
651         snd_card_info_entry = entry;
652
653 #ifdef MODULE
654         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
655         if (entry) {
656                 entry->c.text.read = snd_card_module_info_read;
657                 if (snd_info_register(entry) < 0)
658                         snd_info_free_entry(entry);
659                 else
660                         snd_card_module_info_entry = entry;
661         }
662 #endif
663
664         return 0;
665 }
666
667 int __exit snd_card_info_done(void)
668 {
669         snd_info_free_entry(snd_card_info_entry);
670 #ifdef MODULE
671         snd_info_free_entry(snd_card_module_info_entry);
672 #endif
673         return 0;
674 }
675
676 #endif /* CONFIG_PROC_FS */
677
678 /**
679  *  snd_component_add - add a component string
680  *  @card: soundcard structure
681  *  @component: the component id string
682  *
683  *  This function adds the component id string to the supported list.
684  *  The component can be referred from the alsa-lib.
685  *
686  *  Returns zero otherwise a negative error code.
687  */
688   
689 int snd_component_add(struct snd_card *card, const char *component)
690 {
691         char *ptr;
692         int len = strlen(component);
693
694         ptr = strstr(card->components, component);
695         if (ptr != NULL) {
696                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
697                         return 1;
698         }
699         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
700                 snd_BUG();
701                 return -ENOMEM;
702         }
703         if (card->components[0] != '\0')
704                 strcat(card->components, " ");
705         strcat(card->components, component);
706         return 0;
707 }
708
709 EXPORT_SYMBOL(snd_component_add);
710
711 /**
712  *  snd_card_file_add - add the file to the file list of the card
713  *  @card: soundcard structure
714  *  @file: file pointer
715  *
716  *  This function adds the file to the file linked-list of the card.
717  *  This linked-list is used to keep tracking the connection state,
718  *  and to avoid the release of busy resources by hotplug.
719  *
720  *  Returns zero or a negative error code.
721  */
722 int snd_card_file_add(struct snd_card *card, struct file *file)
723 {
724         struct snd_monitor_file *mfile;
725
726         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
727         if (mfile == NULL)
728                 return -ENOMEM;
729         mfile->file = file;
730         mfile->disconnected_f_op = NULL;
731         mfile->next = NULL;
732         spin_lock(&card->files_lock);
733         if (card->shutdown) {
734                 spin_unlock(&card->files_lock);
735                 kfree(mfile);
736                 return -ENODEV;
737         }
738         mfile->next = card->files;
739         card->files = mfile;
740         spin_unlock(&card->files_lock);
741         return 0;
742 }
743
744 EXPORT_SYMBOL(snd_card_file_add);
745
746 /**
747  *  snd_card_file_remove - remove the file from the file list
748  *  @card: soundcard structure
749  *  @file: file pointer
750  *
751  *  This function removes the file formerly added to the card via
752  *  snd_card_file_add() function.
753  *  If all files are removed and snd_card_free_when_closed() was
754  *  called beforehand, it processes the pending release of
755  *  resources.
756  *
757  *  Returns zero or a negative error code.
758  */
759 int snd_card_file_remove(struct snd_card *card, struct file *file)
760 {
761         struct snd_monitor_file *mfile, *pfile = NULL;
762         int last_close = 0;
763
764         spin_lock(&card->files_lock);
765         mfile = card->files;
766         while (mfile) {
767                 if (mfile->file == file) {
768                         if (pfile)
769                                 pfile->next = mfile->next;
770                         else
771                                 card->files = mfile->next;
772                         break;
773                 }
774                 pfile = mfile;
775                 mfile = mfile->next;
776         }
777         if (mfile && mfile->disconnected_f_op) {
778                 fops_put(mfile->disconnected_f_op);
779                 spin_lock(&shutdown_lock);
780                 list_del(&mfile->shutdown_list);
781                 spin_unlock(&shutdown_lock);
782         }
783         if (card->files == NULL)
784                 last_close = 1;
785         spin_unlock(&card->files_lock);
786         if (last_close) {
787                 wake_up(&card->shutdown_sleep);
788                 if (card->free_on_last_close)
789                         snd_card_do_free(card);
790         }
791         if (!mfile) {
792                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
793                 return -ENOENT;
794         }
795         kfree(mfile);
796         return 0;
797 }
798
799 EXPORT_SYMBOL(snd_card_file_remove);
800
801 #ifdef CONFIG_PM
802 /**
803  *  snd_power_wait - wait until the power-state is changed.
804  *  @card: soundcard structure
805  *  @power_state: expected power state
806  *
807  *  Waits until the power-state is changed.
808  *
809  *  Note: the power lock must be active before call.
810  */
811 int snd_power_wait(struct snd_card *card, unsigned int power_state)
812 {
813         wait_queue_t wait;
814         int result = 0;
815
816         /* fastpath */
817         if (snd_power_get_state(card) == power_state)
818                 return 0;
819         init_waitqueue_entry(&wait, current);
820         add_wait_queue(&card->power_sleep, &wait);
821         while (1) {
822                 if (card->shutdown) {
823                         result = -ENODEV;
824                         break;
825                 }
826                 if (snd_power_get_state(card) == power_state)
827                         break;
828                 set_current_state(TASK_UNINTERRUPTIBLE);
829                 snd_power_unlock(card);
830                 schedule_timeout(30 * HZ);
831                 snd_power_lock(card);
832         }
833         remove_wait_queue(&card->power_sleep, &wait);
834         return result;
835 }
836
837 EXPORT_SYMBOL(snd_power_wait);
838 #endif /* CONFIG_PM */