device create: sound: convert device_create to device_create_drvdata
[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 reserved for the given
50  * module via slots option
51  */
52 static int module_slot_match(struct module *module, int idx)
53 {
54         int match = 1;
55 #ifdef MODULE
56         const char *s1, *s2;
57
58         if (!module || !module->name || !slots[idx])
59                 return 0;
60
61         s1 = module->name;
62         s2 = slots[idx];
63         if (*s2 == '!') {
64                 match = 0; /* negative match */
65                 s2++;
66         }
67         /* compare module name strings
68          * hyphens are handled as equivalent with underscore
69          */
70         for (;;) {
71                 char c1 = *s1++;
72                 char c2 = *s2++;
73                 if (c1 == '-')
74                         c1 = '_';
75                 if (c2 == '-')
76                         c2 = '_';
77                 if (c1 != c2)
78                         return !match;
79                 if (!c1)
80                         break;
81         }
82 #endif /* MODULE */
83         return match;
84 }
85
86 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
87 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
88 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
89 #endif
90
91 #ifdef CONFIG_PROC_FS
92 static void snd_card_id_read(struct snd_info_entry *entry,
93                              struct snd_info_buffer *buffer)
94 {
95         snd_iprintf(buffer, "%s\n", entry->card->id);
96 }
97
98 static inline int init_info_for_card(struct snd_card *card)
99 {
100         int err;
101         struct snd_info_entry *entry;
102
103         if ((err = snd_info_card_register(card)) < 0) {
104                 snd_printd("unable to create card info\n");
105                 return err;
106         }
107         if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
108                 snd_printd("unable to create card entry\n");
109                 return err;
110         }
111         entry->c.text.read = snd_card_id_read;
112         if (snd_info_register(entry) < 0) {
113                 snd_info_free_entry(entry);
114                 entry = NULL;
115         }
116         card->proc_id = entry;
117         return 0;
118 }
119 #else /* !CONFIG_PROC_FS */
120 #define init_info_for_card(card)
121 #endif
122
123 /**
124  *  snd_card_new - create and initialize a soundcard structure
125  *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
126  *  @xid: card identification (ASCII string)
127  *  @module: top level module for locking
128  *  @extra_size: allocate this extra size after the main soundcard structure
129  *
130  *  Creates and initializes a soundcard structure.
131  *
132  *  Returns kmallocated snd_card structure. Creates the ALSA control interface
133  *  (which is blocked until snd_card_register function is called).
134  */
135 struct snd_card *snd_card_new(int idx, const char *xid,
136                          struct module *module, int extra_size)
137 {
138         struct snd_card *card;
139         int err, idx2;
140
141         if (extra_size < 0)
142                 extra_size = 0;
143         card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
144         if (card == NULL)
145                 return NULL;
146         if (xid) {
147                 if (!snd_info_check_reserved_words(xid))
148                         goto __error;
149                 strlcpy(card->id, xid, sizeof(card->id));
150         }
151         err = 0;
152         mutex_lock(&snd_card_mutex);
153         if (idx < 0) {
154                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
155                         /* idx == -1 == 0xffff means: take any free slot */
156                         if (~snd_cards_lock & idx & 1<<idx2) {
157                                 if (module_slot_match(module, idx2)) {
158                                         idx = idx2;
159                                         break;
160                                 }
161                         }
162         }
163         if (idx < 0) {
164                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
165                         /* idx == -1 == 0xffff means: take any free slot */
166                         if (~snd_cards_lock & idx & 1<<idx2) {
167                                 if (!slots[idx2] || !*slots[idx2]) {
168                                         idx = idx2;
169                                         break;
170                                 }
171                         }
172         }
173         if (idx < 0)
174                 err = -ENODEV;
175         else if (idx < snd_ecards_limit) {
176                 if (snd_cards_lock & (1 << idx))
177                         err = -EBUSY;   /* invalid */
178         } else if (idx >= SNDRV_CARDS)
179                 err = -ENODEV;
180         if (err < 0) {
181                 mutex_unlock(&snd_card_mutex);
182                 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
183                          idx, snd_ecards_limit - 1, err);
184                 goto __error;
185         }
186         snd_cards_lock |= 1 << idx;             /* lock it */
187         if (idx >= snd_ecards_limit)
188                 snd_ecards_limit = idx + 1; /* increase the limit */
189         mutex_unlock(&snd_card_mutex);
190         card->number = idx;
191         card->module = module;
192         INIT_LIST_HEAD(&card->devices);
193         init_rwsem(&card->controls_rwsem);
194         rwlock_init(&card->ctl_files_rwlock);
195         INIT_LIST_HEAD(&card->controls);
196         INIT_LIST_HEAD(&card->ctl_files);
197         spin_lock_init(&card->files_lock);
198         init_waitqueue_head(&card->shutdown_sleep);
199 #ifdef CONFIG_PM
200         mutex_init(&card->power_lock);
201         init_waitqueue_head(&card->power_sleep);
202 #endif
203         /* the control interface cannot be accessed from the user space until */
204         /* snd_cards_bitmask and snd_cards are set with snd_card_register */
205         if ((err = snd_ctl_create(card)) < 0) {
206                 snd_printd("unable to register control minors\n");
207                 goto __error;
208         }
209         if ((err = snd_info_card_create(card)) < 0) {
210                 snd_printd("unable to create card info\n");
211                 goto __error_ctl;
212         }
213         if (extra_size > 0)
214                 card->private_data = (char *)card + sizeof(struct snd_card);
215         return card;
216
217       __error_ctl:
218         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
219       __error:
220         kfree(card);
221         return NULL;
222 }
223
224 EXPORT_SYMBOL(snd_card_new);
225
226 /* return non-zero if a card is already locked */
227 int snd_card_locked(int card)
228 {
229         int locked;
230
231         mutex_lock(&snd_card_mutex);
232         locked = snd_cards_lock & (1 << card);
233         mutex_unlock(&snd_card_mutex);
234         return locked;
235 }
236
237 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
238 {
239         return -ENODEV;
240 }
241
242 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
243                                    size_t count, loff_t *offset)
244 {
245         return -ENODEV;
246 }
247
248 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
249                                     size_t count, loff_t *offset)
250 {
251         return -ENODEV;
252 }
253
254 static int snd_disconnect_release(struct inode *inode, struct file *file)
255 {
256         struct snd_monitor_file *df = NULL, *_df;
257
258         spin_lock(&shutdown_lock);
259         list_for_each_entry(_df, &shutdown_files, shutdown_list) {
260                 if (_df->file == file) {
261                         df = _df;
262                         break;
263                 }
264         }
265         spin_unlock(&shutdown_lock);
266
267         if (likely(df))
268                 return df->disconnected_f_op->release(inode, file);
269
270         panic("%s(%p, %p) failed!", __func__, inode, file);
271 }
272
273 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
274 {
275         return POLLERR | POLLNVAL;
276 }
277
278 static long snd_disconnect_ioctl(struct file *file,
279                                  unsigned int cmd, unsigned long arg)
280 {
281         return -ENODEV;
282 }
283
284 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
285 {
286         return -ENODEV;
287 }
288
289 static int snd_disconnect_fasync(int fd, struct file *file, int on)
290 {
291         return -ENODEV;
292 }
293
294 static const struct file_operations snd_shutdown_f_ops =
295 {
296         .owner =        THIS_MODULE,
297         .llseek =       snd_disconnect_llseek,
298         .read =         snd_disconnect_read,
299         .write =        snd_disconnect_write,
300         .release =      snd_disconnect_release,
301         .poll =         snd_disconnect_poll,
302         .unlocked_ioctl = snd_disconnect_ioctl,
303 #ifdef CONFIG_COMPAT
304         .compat_ioctl = snd_disconnect_ioctl,
305 #endif
306         .mmap =         snd_disconnect_mmap,
307         .fasync =       snd_disconnect_fasync
308 };
309
310 /**
311  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
312  *  @card: soundcard structure
313  *
314  *  Disconnects all APIs from the file-operations (user space).
315  *
316  *  Returns zero, otherwise a negative error code.
317  *
318  *  Note: The current implementation replaces all active file->f_op with special
319  *        dummy file operations (they do nothing except release).
320  */
321 int snd_card_disconnect(struct snd_card *card)
322 {
323         struct snd_monitor_file *mfile;
324         struct file *file;
325         int err;
326
327         if (!card)
328                 return -EINVAL;
329
330         spin_lock(&card->files_lock);
331         if (card->shutdown) {
332                 spin_unlock(&card->files_lock);
333                 return 0;
334         }
335         card->shutdown = 1;
336         spin_unlock(&card->files_lock);
337
338         /* phase 1: disable fops (user space) operations for ALSA API */
339         mutex_lock(&snd_card_mutex);
340         snd_cards[card->number] = NULL;
341         snd_cards_lock &= ~(1 << card->number);
342         mutex_unlock(&snd_card_mutex);
343         
344         /* phase 2: replace file->f_op with special dummy operations */
345         
346         spin_lock(&card->files_lock);
347         mfile = card->files;
348         while (mfile) {
349                 file = mfile->file;
350
351                 /* it's critical part, use endless loop */
352                 /* we have no room to fail */
353                 mfile->disconnected_f_op = mfile->file->f_op;
354
355                 spin_lock(&shutdown_lock);
356                 list_add(&mfile->shutdown_list, &shutdown_files);
357                 spin_unlock(&shutdown_lock);
358
359                 mfile->file->f_op = &snd_shutdown_f_ops;
360                 fops_get(mfile->file->f_op);
361                 
362                 mfile = mfile->next;
363         }
364         spin_unlock(&card->files_lock); 
365
366         /* phase 3: notify all connected devices about disconnection */
367         /* at this point, they cannot respond to any calls except release() */
368
369 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
370         if (snd_mixer_oss_notify_callback)
371                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
372 #endif
373
374         /* notify all devices that we are disconnected */
375         err = snd_device_disconnect_all(card);
376         if (err < 0)
377                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
378
379         snd_info_card_disconnect(card);
380 #ifndef CONFIG_SYSFS_DEPRECATED
381         if (card->card_dev) {
382                 device_unregister(card->card_dev);
383                 card->card_dev = NULL;
384         }
385 #endif
386 #ifdef CONFIG_PM
387         wake_up(&card->power_sleep);
388 #endif
389         return 0;       
390 }
391
392 EXPORT_SYMBOL(snd_card_disconnect);
393
394 /**
395  *  snd_card_free - frees given soundcard structure
396  *  @card: soundcard structure
397  *
398  *  This function releases the soundcard structure and the all assigned
399  *  devices automatically.  That is, you don't have to release the devices
400  *  by yourself.
401  *
402  *  Returns zero. Frees all associated devices and frees the control
403  *  interface associated to given soundcard.
404  */
405 static int snd_card_do_free(struct snd_card *card)
406 {
407 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
408         if (snd_mixer_oss_notify_callback)
409                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
410 #endif
411         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
412                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
413                 /* Fatal, but this situation should never occur */
414         }
415         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
416                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
417                 /* Fatal, but this situation should never occur */
418         }
419         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
420                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
421                 /* Fatal, but this situation should never occur */
422         }
423         if (card->private_free)
424                 card->private_free(card);
425         snd_info_free_entry(card->proc_id);
426         if (snd_info_card_free(card) < 0) {
427                 snd_printk(KERN_WARNING "unable to free card info\n");
428                 /* Not fatal error */
429         }
430         kfree(card);
431         return 0;
432 }
433
434 int snd_card_free_when_closed(struct snd_card *card)
435 {
436         int free_now = 0;
437         int ret = snd_card_disconnect(card);
438         if (ret)
439                 return ret;
440
441         spin_lock(&card->files_lock);
442         if (card->files == NULL)
443                 free_now = 1;
444         else
445                 card->free_on_last_close = 1;
446         spin_unlock(&card->files_lock);
447
448         if (free_now)
449                 snd_card_do_free(card);
450         return 0;
451 }
452
453 EXPORT_SYMBOL(snd_card_free_when_closed);
454
455 int snd_card_free(struct snd_card *card)
456 {
457         int ret = snd_card_disconnect(card);
458         if (ret)
459                 return ret;
460
461         /* wait, until all devices are ready for the free operation */
462         wait_event(card->shutdown_sleep, card->files == NULL);
463         snd_card_do_free(card);
464         return 0;
465 }
466
467 EXPORT_SYMBOL(snd_card_free);
468
469 static void choose_default_id(struct snd_card *card)
470 {
471         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
472         char *id, *spos;
473         
474         id = spos = card->shortname;    
475         while (*id != '\0') {
476                 if (*id == ' ')
477                         spos = id + 1;
478                 id++;
479         }
480         id = card->id;
481         while (*spos != '\0' && !isalnum(*spos))
482                 spos++;
483         if (isdigit(*spos))
484                 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
485         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
486                 if (isalnum(*spos))
487                         *id++ = *spos;
488                 spos++;
489         }
490         *id = '\0';
491
492         id = card->id;
493         
494         if (*id == '\0')
495                 strcpy(id, "default");
496
497         while (1) {
498                 if (loops-- == 0) {
499                         snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
500                         strcpy(card->id, card->proc_root->name);
501                         return;
502                 }
503                 if (!snd_info_check_reserved_words(id))
504                         goto __change;
505                 for (i = 0; i < snd_ecards_limit; i++) {
506                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
507                                 goto __change;
508                 }
509                 break;
510
511               __change:
512                 len = strlen(id);
513                 if (idx_flag) {
514                         if (id[len-1] != '9')
515                                 id[len-1]++;
516                         else
517                                 id[len-1] = 'A';
518                 } else if ((size_t)len <= sizeof(card->id) - 3) {
519                         strcat(id, "_1");
520                         idx_flag++;
521                 } else {
522                         spos = id + len - 2;
523                         if ((size_t)len <= sizeof(card->id) - 2)
524                                 spos++;
525                         *spos++ = '_';
526                         *spos++ = '1';
527                         *spos++ = '\0';
528                         idx_flag++;
529                 }
530         }
531 }
532
533 /**
534  *  snd_card_register - register the soundcard
535  *  @card: soundcard structure
536  *
537  *  This function registers all the devices assigned to the soundcard.
538  *  Until calling this, the ALSA control interface is blocked from the
539  *  external accesses.  Thus, you should call this function at the end
540  *  of the initialization of the card.
541  *
542  *  Returns zero otherwise a negative error code if the registrain failed.
543  */
544 int snd_card_register(struct snd_card *card)
545 {
546         int err;
547
548         snd_assert(card != NULL, return -EINVAL);
549 #ifndef CONFIG_SYSFS_DEPRECATED
550         if (!card->card_dev) {
551                 card->card_dev = device_create_drvdata(sound_class, card->dev,
552                                                        MKDEV(0, 0), NULL,
553                                                        "card%i", card->number);
554                 if (IS_ERR(card->card_dev))
555                         card->card_dev = NULL;
556         }
557 #endif
558         if ((err = snd_device_register_all(card)) < 0)
559                 return err;
560         mutex_lock(&snd_card_mutex);
561         if (snd_cards[card->number]) {
562                 /* already registered */
563                 mutex_unlock(&snd_card_mutex);
564                 return 0;
565         }
566         if (card->id[0] == '\0')
567                 choose_default_id(card);
568         snd_cards[card->number] = card;
569         mutex_unlock(&snd_card_mutex);
570         init_info_for_card(card);
571 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
572         if (snd_mixer_oss_notify_callback)
573                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
574 #endif
575         return 0;
576 }
577
578 EXPORT_SYMBOL(snd_card_register);
579
580 #ifdef CONFIG_PROC_FS
581 static struct snd_info_entry *snd_card_info_entry;
582
583 static void snd_card_info_read(struct snd_info_entry *entry,
584                                struct snd_info_buffer *buffer)
585 {
586         int idx, count;
587         struct snd_card *card;
588
589         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
590                 mutex_lock(&snd_card_mutex);
591                 if ((card = snd_cards[idx]) != NULL) {
592                         count++;
593                         snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
594                                         idx,
595                                         card->id,
596                                         card->driver,
597                                         card->shortname);
598                         snd_iprintf(buffer, "                      %s\n",
599                                         card->longname);
600                 }
601                 mutex_unlock(&snd_card_mutex);
602         }
603         if (!count)
604                 snd_iprintf(buffer, "--- no soundcards ---\n");
605 }
606
607 #ifdef CONFIG_SND_OSSEMUL
608
609 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
610 {
611         int idx, count;
612         struct snd_card *card;
613
614         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
615                 mutex_lock(&snd_card_mutex);
616                 if ((card = snd_cards[idx]) != NULL) {
617                         count++;
618                         snd_iprintf(buffer, "%s\n", card->longname);
619                 }
620                 mutex_unlock(&snd_card_mutex);
621         }
622         if (!count) {
623                 snd_iprintf(buffer, "--- no soundcards ---\n");
624         }
625 }
626
627 #endif
628
629 #ifdef MODULE
630 static struct snd_info_entry *snd_card_module_info_entry;
631 static void snd_card_module_info_read(struct snd_info_entry *entry,
632                                       struct snd_info_buffer *buffer)
633 {
634         int idx;
635         struct snd_card *card;
636
637         for (idx = 0; idx < SNDRV_CARDS; idx++) {
638                 mutex_lock(&snd_card_mutex);
639                 if ((card = snd_cards[idx]) != NULL)
640                         snd_iprintf(buffer, "%2i %s\n",
641                                     idx, card->module->name);
642                 mutex_unlock(&snd_card_mutex);
643         }
644 }
645 #endif
646
647 int __init snd_card_info_init(void)
648 {
649         struct snd_info_entry *entry;
650
651         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
652         if (! entry)
653                 return -ENOMEM;
654         entry->c.text.read = snd_card_info_read;
655         if (snd_info_register(entry) < 0) {
656                 snd_info_free_entry(entry);
657                 return -ENOMEM;
658         }
659         snd_card_info_entry = entry;
660
661 #ifdef MODULE
662         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
663         if (entry) {
664                 entry->c.text.read = snd_card_module_info_read;
665                 if (snd_info_register(entry) < 0)
666                         snd_info_free_entry(entry);
667                 else
668                         snd_card_module_info_entry = entry;
669         }
670 #endif
671
672         return 0;
673 }
674
675 int __exit snd_card_info_done(void)
676 {
677         snd_info_free_entry(snd_card_info_entry);
678 #ifdef MODULE
679         snd_info_free_entry(snd_card_module_info_entry);
680 #endif
681         return 0;
682 }
683
684 #endif /* CONFIG_PROC_FS */
685
686 /**
687  *  snd_component_add - add a component string
688  *  @card: soundcard structure
689  *  @component: the component id string
690  *
691  *  This function adds the component id string to the supported list.
692  *  The component can be referred from the alsa-lib.
693  *
694  *  Returns zero otherwise a negative error code.
695  */
696   
697 int snd_component_add(struct snd_card *card, const char *component)
698 {
699         char *ptr;
700         int len = strlen(component);
701
702         ptr = strstr(card->components, component);
703         if (ptr != NULL) {
704                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
705                         return 1;
706         }
707         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
708                 snd_BUG();
709                 return -ENOMEM;
710         }
711         if (card->components[0] != '\0')
712                 strcat(card->components, " ");
713         strcat(card->components, component);
714         return 0;
715 }
716
717 EXPORT_SYMBOL(snd_component_add);
718
719 /**
720  *  snd_card_file_add - add the file to the file list of the card
721  *  @card: soundcard structure
722  *  @file: file pointer
723  *
724  *  This function adds the file to the file linked-list of the card.
725  *  This linked-list is used to keep tracking the connection state,
726  *  and to avoid the release of busy resources by hotplug.
727  *
728  *  Returns zero or a negative error code.
729  */
730 int snd_card_file_add(struct snd_card *card, struct file *file)
731 {
732         struct snd_monitor_file *mfile;
733
734         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
735         if (mfile == NULL)
736                 return -ENOMEM;
737         mfile->file = file;
738         mfile->disconnected_f_op = NULL;
739         mfile->next = NULL;
740         spin_lock(&card->files_lock);
741         if (card->shutdown) {
742                 spin_unlock(&card->files_lock);
743                 kfree(mfile);
744                 return -ENODEV;
745         }
746         mfile->next = card->files;
747         card->files = mfile;
748         spin_unlock(&card->files_lock);
749         return 0;
750 }
751
752 EXPORT_SYMBOL(snd_card_file_add);
753
754 /**
755  *  snd_card_file_remove - remove the file from the file list
756  *  @card: soundcard structure
757  *  @file: file pointer
758  *
759  *  This function removes the file formerly added to the card via
760  *  snd_card_file_add() function.
761  *  If all files are removed and snd_card_free_when_closed() was
762  *  called beforehand, it processes the pending release of
763  *  resources.
764  *
765  *  Returns zero or a negative error code.
766  */
767 int snd_card_file_remove(struct snd_card *card, struct file *file)
768 {
769         struct snd_monitor_file *mfile, *pfile = NULL;
770         int last_close = 0;
771
772         spin_lock(&card->files_lock);
773         mfile = card->files;
774         while (mfile) {
775                 if (mfile->file == file) {
776                         if (pfile)
777                                 pfile->next = mfile->next;
778                         else
779                                 card->files = mfile->next;
780                         break;
781                 }
782                 pfile = mfile;
783                 mfile = mfile->next;
784         }
785         if (mfile && mfile->disconnected_f_op) {
786                 fops_put(mfile->disconnected_f_op);
787                 spin_lock(&shutdown_lock);
788                 list_del(&mfile->shutdown_list);
789                 spin_unlock(&shutdown_lock);
790         }
791         if (card->files == NULL)
792                 last_close = 1;
793         spin_unlock(&card->files_lock);
794         if (last_close) {
795                 wake_up(&card->shutdown_sleep);
796                 if (card->free_on_last_close)
797                         snd_card_do_free(card);
798         }
799         if (!mfile) {
800                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
801                 return -ENOENT;
802         }
803         kfree(mfile);
804         return 0;
805 }
806
807 EXPORT_SYMBOL(snd_card_file_remove);
808
809 #ifdef CONFIG_PM
810 /**
811  *  snd_power_wait - wait until the power-state is changed.
812  *  @card: soundcard structure
813  *  @power_state: expected power state
814  *
815  *  Waits until the power-state is changed.
816  *
817  *  Note: the power lock must be active before call.
818  */
819 int snd_power_wait(struct snd_card *card, unsigned int power_state)
820 {
821         wait_queue_t wait;
822         int result = 0;
823
824         /* fastpath */
825         if (snd_power_get_state(card) == power_state)
826                 return 0;
827         init_waitqueue_entry(&wait, current);
828         add_wait_queue(&card->power_sleep, &wait);
829         while (1) {
830                 if (card->shutdown) {
831                         result = -ENODEV;
832                         break;
833                 }
834                 if (snd_power_get_state(card) == power_state)
835                         break;
836                 set_current_state(TASK_UNINTERRUPTIBLE);
837                 snd_power_unlock(card);
838                 schedule_timeout(30 * HZ);
839                 snd_power_lock(card);
840         }
841         remove_wait_queue(&card->power_sleep, &wait);
842         return result;
843 }
844
845 EXPORT_SYMBOL(snd_power_wait);
846 #endif /* CONFIG_PM */