Merge branch 'master' into devel
[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 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_create - 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  *  @card_ret: the pointer to store the created card instance
130  *
131  *  Creates and initializes a soundcard structure.
132  *
133  *  The function allocates snd_card instance via kzalloc with the given
134  *  space for the driver to use freely.  The allocated struct is stored
135  *  in the given card_ret pointer.
136  *
137  *  Returns zero if successful or a negative error code.
138  */
139 int snd_card_create(int idx, const char *xid,
140                     struct module *module, int extra_size,
141                     struct snd_card **card_ret)
142 {
143         struct snd_card *card;
144         int err, idx2;
145
146         if (snd_BUG_ON(!card_ret))
147                 return -EINVAL;
148         *card_ret = NULL;
149
150         if (extra_size < 0)
151                 extra_size = 0;
152         card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
153         if (!card)
154                 return -ENOMEM;
155         if (xid) {
156                 if (!snd_info_check_reserved_words(xid)) {
157                         snd_printk(KERN_ERR
158                                    "given id string '%s' is reserved.\n", xid);
159                         err = -EBUSY;
160                         goto __error;
161                 }
162                 strlcpy(card->id, xid, sizeof(card->id));
163         }
164         err = 0;
165         mutex_lock(&snd_card_mutex);
166         if (idx < 0) {
167                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
168                         /* idx == -1 == 0xffff means: take any free slot */
169                         if (~snd_cards_lock & idx & 1<<idx2) {
170                                 if (module_slot_match(module, idx2)) {
171                                         idx = idx2;
172                                         break;
173                                 }
174                         }
175         }
176         if (idx < 0) {
177                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
178                         /* idx == -1 == 0xffff means: take any free slot */
179                         if (~snd_cards_lock & idx & 1<<idx2) {
180                                 if (!slots[idx2] || !*slots[idx2]) {
181                                         idx = idx2;
182                                         break;
183                                 }
184                         }
185         }
186         if (idx < 0)
187                 err = -ENODEV;
188         else if (idx < snd_ecards_limit) {
189                 if (snd_cards_lock & (1 << idx))
190                         err = -EBUSY;   /* invalid */
191         } else if (idx >= SNDRV_CARDS)
192                 err = -ENODEV;
193         if (err < 0) {
194                 mutex_unlock(&snd_card_mutex);
195                 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
196                          idx, snd_ecards_limit - 1, err);
197                 goto __error;
198         }
199         snd_cards_lock |= 1 << idx;             /* lock it */
200         if (idx >= snd_ecards_limit)
201                 snd_ecards_limit = idx + 1; /* increase the limit */
202         mutex_unlock(&snd_card_mutex);
203         card->number = idx;
204         card->module = module;
205         INIT_LIST_HEAD(&card->devices);
206         init_rwsem(&card->controls_rwsem);
207         rwlock_init(&card->ctl_files_rwlock);
208         INIT_LIST_HEAD(&card->controls);
209         INIT_LIST_HEAD(&card->ctl_files);
210         spin_lock_init(&card->files_lock);
211         INIT_LIST_HEAD(&card->files_list);
212         init_waitqueue_head(&card->shutdown_sleep);
213 #ifdef CONFIG_PM
214         mutex_init(&card->power_lock);
215         init_waitqueue_head(&card->power_sleep);
216 #endif
217         /* the control interface cannot be accessed from the user space until */
218         /* snd_cards_bitmask and snd_cards are set with snd_card_register */
219         err = snd_ctl_create(card);
220         if (err < 0) {
221                 snd_printk(KERN_ERR "unable to register control minors\n");
222                 goto __error;
223         }
224         err = snd_info_card_create(card);
225         if (err < 0) {
226                 snd_printk(KERN_ERR "unable to create card info\n");
227                 goto __error_ctl;
228         }
229         if (extra_size > 0)
230                 card->private_data = (char *)card + sizeof(struct snd_card);
231         *card_ret = card;
232         return 0;
233
234       __error_ctl:
235         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
236       __error:
237         kfree(card);
238         return err;
239 }
240 EXPORT_SYMBOL(snd_card_create);
241
242 /* return non-zero if a card is already locked */
243 int snd_card_locked(int card)
244 {
245         int locked;
246
247         mutex_lock(&snd_card_mutex);
248         locked = snd_cards_lock & (1 << card);
249         mutex_unlock(&snd_card_mutex);
250         return locked;
251 }
252
253 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
254 {
255         return -ENODEV;
256 }
257
258 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
259                                    size_t count, loff_t *offset)
260 {
261         return -ENODEV;
262 }
263
264 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
265                                     size_t count, loff_t *offset)
266 {
267         return -ENODEV;
268 }
269
270 static int snd_disconnect_release(struct inode *inode, struct file *file)
271 {
272         struct snd_monitor_file *df = NULL, *_df;
273
274         spin_lock(&shutdown_lock);
275         list_for_each_entry(_df, &shutdown_files, shutdown_list) {
276                 if (_df->file == file) {
277                         df = _df;
278                         list_del_init(&df->shutdown_list);
279                         break;
280                 }
281         }
282         spin_unlock(&shutdown_lock);
283
284         if (likely(df)) {
285                 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
286                         df->disconnected_f_op->fasync(-1, file, 0);
287                 return df->disconnected_f_op->release(inode, file);
288         }
289
290         panic("%s(%p, %p) failed!", __func__, inode, file);
291 }
292
293 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
294 {
295         return POLLERR | POLLNVAL;
296 }
297
298 static long snd_disconnect_ioctl(struct file *file,
299                                  unsigned int cmd, unsigned long arg)
300 {
301         return -ENODEV;
302 }
303
304 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
305 {
306         return -ENODEV;
307 }
308
309 static int snd_disconnect_fasync(int fd, struct file *file, int on)
310 {
311         return -ENODEV;
312 }
313
314 static const struct file_operations snd_shutdown_f_ops =
315 {
316         .owner =        THIS_MODULE,
317         .llseek =       snd_disconnect_llseek,
318         .read =         snd_disconnect_read,
319         .write =        snd_disconnect_write,
320         .release =      snd_disconnect_release,
321         .poll =         snd_disconnect_poll,
322         .unlocked_ioctl = snd_disconnect_ioctl,
323 #ifdef CONFIG_COMPAT
324         .compat_ioctl = snd_disconnect_ioctl,
325 #endif
326         .mmap =         snd_disconnect_mmap,
327         .fasync =       snd_disconnect_fasync
328 };
329
330 /**
331  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
332  *  @card: soundcard structure
333  *
334  *  Disconnects all APIs from the file-operations (user space).
335  *
336  *  Returns zero, otherwise a negative error code.
337  *
338  *  Note: The current implementation replaces all active file->f_op with special
339  *        dummy file operations (they do nothing except release).
340  */
341 int snd_card_disconnect(struct snd_card *card)
342 {
343         struct snd_monitor_file *mfile;
344         struct file *file;
345         int err;
346
347         if (!card)
348                 return -EINVAL;
349
350         spin_lock(&card->files_lock);
351         if (card->shutdown) {
352                 spin_unlock(&card->files_lock);
353                 return 0;
354         }
355         card->shutdown = 1;
356         spin_unlock(&card->files_lock);
357
358         /* phase 1: disable fops (user space) operations for ALSA API */
359         mutex_lock(&snd_card_mutex);
360         snd_cards[card->number] = NULL;
361         snd_cards_lock &= ~(1 << card->number);
362         mutex_unlock(&snd_card_mutex);
363         
364         /* phase 2: replace file->f_op with special dummy operations */
365         
366         spin_lock(&card->files_lock);
367         list_for_each_entry(mfile, &card->files_list, list) {
368                 file = mfile->file;
369
370                 /* it's critical part, use endless loop */
371                 /* we have no room to fail */
372                 mfile->disconnected_f_op = mfile->file->f_op;
373
374                 spin_lock(&shutdown_lock);
375                 list_add(&mfile->shutdown_list, &shutdown_files);
376                 spin_unlock(&shutdown_lock);
377
378                 mfile->file->f_op = &snd_shutdown_f_ops;
379                 fops_get(mfile->file->f_op);
380         }
381         spin_unlock(&card->files_lock); 
382
383         /* phase 3: notify all connected devices about disconnection */
384         /* at this point, they cannot respond to any calls except release() */
385
386 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
387         if (snd_mixer_oss_notify_callback)
388                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
389 #endif
390
391         /* notify all devices that we are disconnected */
392         err = snd_device_disconnect_all(card);
393         if (err < 0)
394                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
395
396         snd_info_card_disconnect(card);
397 #ifndef CONFIG_SYSFS_DEPRECATED
398         if (card->card_dev) {
399                 device_unregister(card->card_dev);
400                 card->card_dev = NULL;
401         }
402 #endif
403 #ifdef CONFIG_PM
404         wake_up(&card->power_sleep);
405 #endif
406         return 0;       
407 }
408
409 EXPORT_SYMBOL(snd_card_disconnect);
410
411 /**
412  *  snd_card_free - frees given soundcard structure
413  *  @card: soundcard structure
414  *
415  *  This function releases the soundcard structure and the all assigned
416  *  devices automatically.  That is, you don't have to release the devices
417  *  by yourself.
418  *
419  *  Returns zero. Frees all associated devices and frees the control
420  *  interface associated to given soundcard.
421  */
422 static int snd_card_do_free(struct snd_card *card)
423 {
424 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
425         if (snd_mixer_oss_notify_callback)
426                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
427 #endif
428         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
429                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
430                 /* Fatal, but this situation should never occur */
431         }
432         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
433                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
434                 /* Fatal, but this situation should never occur */
435         }
436         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
437                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
438                 /* Fatal, but this situation should never occur */
439         }
440         if (card->private_free)
441                 card->private_free(card);
442         snd_info_free_entry(card->proc_id);
443         if (snd_info_card_free(card) < 0) {
444                 snd_printk(KERN_WARNING "unable to free card info\n");
445                 /* Not fatal error */
446         }
447         kfree(card);
448         return 0;
449 }
450
451 int snd_card_free_when_closed(struct snd_card *card)
452 {
453         int free_now = 0;
454         int ret = snd_card_disconnect(card);
455         if (ret)
456                 return ret;
457
458         spin_lock(&card->files_lock);
459         if (list_empty(&card->files_list))
460                 free_now = 1;
461         else
462                 card->free_on_last_close = 1;
463         spin_unlock(&card->files_lock);
464
465         if (free_now)
466                 snd_card_do_free(card);
467         return 0;
468 }
469
470 EXPORT_SYMBOL(snd_card_free_when_closed);
471
472 int snd_card_free(struct snd_card *card)
473 {
474         int ret = snd_card_disconnect(card);
475         if (ret)
476                 return ret;
477
478         /* wait, until all devices are ready for the free operation */
479         wait_event(card->shutdown_sleep, list_empty(&card->files_list));
480         snd_card_do_free(card);
481         return 0;
482 }
483
484 EXPORT_SYMBOL(snd_card_free);
485
486 static void choose_default_id(struct snd_card *card)
487 {
488         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
489         char *id, *spos;
490         
491         id = spos = card->shortname;    
492         while (*id != '\0') {
493                 if (*id == ' ')
494                         spos = id + 1;
495                 id++;
496         }
497         id = card->id;
498         while (*spos != '\0' && !isalnum(*spos))
499                 spos++;
500         if (isdigit(*spos))
501                 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
502         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
503                 if (isalnum(*spos))
504                         *id++ = *spos;
505                 spos++;
506         }
507         *id = '\0';
508
509         id = card->id;
510         
511         if (*id == '\0')
512                 strcpy(id, "default");
513
514         while (1) {
515                 if (loops-- == 0) {
516                         snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
517                         strcpy(card->id, card->proc_root->name);
518                         return;
519                 }
520                 if (!snd_info_check_reserved_words(id))
521                         goto __change;
522                 for (i = 0; i < snd_ecards_limit; i++) {
523                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
524                                 goto __change;
525                 }
526                 break;
527
528               __change:
529                 len = strlen(id);
530                 if (idx_flag) {
531                         if (id[len-1] != '9')
532                                 id[len-1]++;
533                         else
534                                 id[len-1] = 'A';
535                 } else if ((size_t)len <= sizeof(card->id) - 3) {
536                         strcat(id, "_1");
537                         idx_flag++;
538                 } else {
539                         spos = id + len - 2;
540                         if ((size_t)len <= sizeof(card->id) - 2)
541                                 spos++;
542                         *spos++ = '_';
543                         *spos++ = '1';
544                         *spos++ = '\0';
545                         idx_flag++;
546                 }
547         }
548 }
549
550 #ifndef CONFIG_SYSFS_DEPRECATED
551 static ssize_t
552 card_id_show_attr(struct device *dev,
553                   struct device_attribute *attr, char *buf)
554 {
555         struct snd_card *card = dev_get_drvdata(dev);
556         return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
557 }
558
559 static ssize_t
560 card_id_store_attr(struct device *dev, struct device_attribute *attr,
561                    const char *buf, size_t count)
562 {
563         struct snd_card *card = dev_get_drvdata(dev);
564         char buf1[sizeof(card->id)];
565         size_t copy = count > sizeof(card->id) - 1 ?
566                                         sizeof(card->id) - 1 : count;
567         size_t idx;
568         int c;
569
570         for (idx = 0; idx < copy; idx++) {
571                 c = buf[idx];
572                 if (!isalnum(c) && c != '_' && c != '-')
573                         return -EINVAL;
574         }
575         memcpy(buf1, buf, copy);
576         buf1[copy] = '\0';
577         mutex_lock(&snd_card_mutex);
578         if (!snd_info_check_reserved_words(buf1)) {
579              __exist:
580                 mutex_unlock(&snd_card_mutex);
581                 return -EEXIST;
582         }
583         for (idx = 0; idx < snd_ecards_limit; idx++) {
584                 if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1))
585                         goto __exist;
586         }
587         strcpy(card->id, buf1);
588         snd_info_card_id_change(card);
589         mutex_unlock(&snd_card_mutex);
590
591         return count;
592 }
593
594 static struct device_attribute card_id_attrs =
595         __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
596
597 static ssize_t
598 card_number_show_attr(struct device *dev,
599                      struct device_attribute *attr, char *buf)
600 {
601         struct snd_card *card = dev_get_drvdata(dev);
602         return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
603 }
604
605 static struct device_attribute card_number_attrs =
606         __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
607 #endif /* CONFIG_SYSFS_DEPRECATED */
608
609 /**
610  *  snd_card_register - register the soundcard
611  *  @card: soundcard structure
612  *
613  *  This function registers all the devices assigned to the soundcard.
614  *  Until calling this, the ALSA control interface is blocked from the
615  *  external accesses.  Thus, you should call this function at the end
616  *  of the initialization of the card.
617  *
618  *  Returns zero otherwise a negative error code if the registrain failed.
619  */
620 int snd_card_register(struct snd_card *card)
621 {
622         int err;
623
624         if (snd_BUG_ON(!card))
625                 return -EINVAL;
626 #ifndef CONFIG_SYSFS_DEPRECATED
627         if (!card->card_dev) {
628                 card->card_dev = device_create(sound_class, card->dev,
629                                                MKDEV(0, 0), card,
630                                                "card%i", card->number);
631                 if (IS_ERR(card->card_dev))
632                         card->card_dev = NULL;
633         }
634 #endif
635         if ((err = snd_device_register_all(card)) < 0)
636                 return err;
637         mutex_lock(&snd_card_mutex);
638         if (snd_cards[card->number]) {
639                 /* already registered */
640                 mutex_unlock(&snd_card_mutex);
641                 return 0;
642         }
643         if (card->id[0] == '\0')
644                 choose_default_id(card);
645         snd_cards[card->number] = card;
646         mutex_unlock(&snd_card_mutex);
647         init_info_for_card(card);
648 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
649         if (snd_mixer_oss_notify_callback)
650                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
651 #endif
652 #ifndef CONFIG_SYSFS_DEPRECATED
653         if (card->card_dev) {
654                 err = device_create_file(card->card_dev, &card_id_attrs);
655                 if (err < 0)
656                         return err;
657                 err = device_create_file(card->card_dev, &card_number_attrs);
658                 if (err < 0)
659                         return err;
660         }
661 #endif
662         return 0;
663 }
664
665 EXPORT_SYMBOL(snd_card_register);
666
667 #ifdef CONFIG_PROC_FS
668 static struct snd_info_entry *snd_card_info_entry;
669
670 static void snd_card_info_read(struct snd_info_entry *entry,
671                                struct snd_info_buffer *buffer)
672 {
673         int idx, count;
674         struct snd_card *card;
675
676         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
677                 mutex_lock(&snd_card_mutex);
678                 if ((card = snd_cards[idx]) != NULL) {
679                         count++;
680                         snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
681                                         idx,
682                                         card->id,
683                                         card->driver,
684                                         card->shortname);
685                         snd_iprintf(buffer, "                      %s\n",
686                                         card->longname);
687                 }
688                 mutex_unlock(&snd_card_mutex);
689         }
690         if (!count)
691                 snd_iprintf(buffer, "--- no soundcards ---\n");
692 }
693
694 #ifdef CONFIG_SND_OSSEMUL
695
696 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
697 {
698         int idx, count;
699         struct snd_card *card;
700
701         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
702                 mutex_lock(&snd_card_mutex);
703                 if ((card = snd_cards[idx]) != NULL) {
704                         count++;
705                         snd_iprintf(buffer, "%s\n", card->longname);
706                 }
707                 mutex_unlock(&snd_card_mutex);
708         }
709         if (!count) {
710                 snd_iprintf(buffer, "--- no soundcards ---\n");
711         }
712 }
713
714 #endif
715
716 #ifdef MODULE
717 static struct snd_info_entry *snd_card_module_info_entry;
718 static void snd_card_module_info_read(struct snd_info_entry *entry,
719                                       struct snd_info_buffer *buffer)
720 {
721         int idx;
722         struct snd_card *card;
723
724         for (idx = 0; idx < SNDRV_CARDS; idx++) {
725                 mutex_lock(&snd_card_mutex);
726                 if ((card = snd_cards[idx]) != NULL)
727                         snd_iprintf(buffer, "%2i %s\n",
728                                     idx, card->module->name);
729                 mutex_unlock(&snd_card_mutex);
730         }
731 }
732 #endif
733
734 int __init snd_card_info_init(void)
735 {
736         struct snd_info_entry *entry;
737
738         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
739         if (! entry)
740                 return -ENOMEM;
741         entry->c.text.read = snd_card_info_read;
742         if (snd_info_register(entry) < 0) {
743                 snd_info_free_entry(entry);
744                 return -ENOMEM;
745         }
746         snd_card_info_entry = entry;
747
748 #ifdef MODULE
749         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
750         if (entry) {
751                 entry->c.text.read = snd_card_module_info_read;
752                 if (snd_info_register(entry) < 0)
753                         snd_info_free_entry(entry);
754                 else
755                         snd_card_module_info_entry = entry;
756         }
757 #endif
758
759         return 0;
760 }
761
762 int __exit snd_card_info_done(void)
763 {
764         snd_info_free_entry(snd_card_info_entry);
765 #ifdef MODULE
766         snd_info_free_entry(snd_card_module_info_entry);
767 #endif
768         return 0;
769 }
770
771 #endif /* CONFIG_PROC_FS */
772
773 /**
774  *  snd_component_add - add a component string
775  *  @card: soundcard structure
776  *  @component: the component id string
777  *
778  *  This function adds the component id string to the supported list.
779  *  The component can be referred from the alsa-lib.
780  *
781  *  Returns zero otherwise a negative error code.
782  */
783   
784 int snd_component_add(struct snd_card *card, const char *component)
785 {
786         char *ptr;
787         int len = strlen(component);
788
789         ptr = strstr(card->components, component);
790         if (ptr != NULL) {
791                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
792                         return 1;
793         }
794         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
795                 snd_BUG();
796                 return -ENOMEM;
797         }
798         if (card->components[0] != '\0')
799                 strcat(card->components, " ");
800         strcat(card->components, component);
801         return 0;
802 }
803
804 EXPORT_SYMBOL(snd_component_add);
805
806 /**
807  *  snd_card_file_add - add the file to the file list of the card
808  *  @card: soundcard structure
809  *  @file: file pointer
810  *
811  *  This function adds the file to the file linked-list of the card.
812  *  This linked-list is used to keep tracking the connection state,
813  *  and to avoid the release of busy resources by hotplug.
814  *
815  *  Returns zero or a negative error code.
816  */
817 int snd_card_file_add(struct snd_card *card, struct file *file)
818 {
819         struct snd_monitor_file *mfile;
820
821         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
822         if (mfile == NULL)
823                 return -ENOMEM;
824         mfile->file = file;
825         mfile->disconnected_f_op = NULL;
826         spin_lock(&card->files_lock);
827         if (card->shutdown) {
828                 spin_unlock(&card->files_lock);
829                 kfree(mfile);
830                 return -ENODEV;
831         }
832         list_add(&mfile->list, &card->files_list);
833         spin_unlock(&card->files_lock);
834         return 0;
835 }
836
837 EXPORT_SYMBOL(snd_card_file_add);
838
839 /**
840  *  snd_card_file_remove - remove the file from the file list
841  *  @card: soundcard structure
842  *  @file: file pointer
843  *
844  *  This function removes the file formerly added to the card via
845  *  snd_card_file_add() function.
846  *  If all files are removed and snd_card_free_when_closed() was
847  *  called beforehand, it processes the pending release of
848  *  resources.
849  *
850  *  Returns zero or a negative error code.
851  */
852 int snd_card_file_remove(struct snd_card *card, struct file *file)
853 {
854         struct snd_monitor_file *mfile, *found = NULL;
855         int last_close = 0;
856
857         spin_lock(&card->files_lock);
858         list_for_each_entry(mfile, &card->files_list, list) {
859                 if (mfile->file == file) {
860                         list_del(&mfile->list);
861                         if (mfile->disconnected_f_op)
862                                 fops_put(mfile->disconnected_f_op);
863                         found = mfile;
864                         break;
865                 }
866         }
867         if (list_empty(&card->files_list))
868                 last_close = 1;
869         spin_unlock(&card->files_lock);
870         if (last_close) {
871                 wake_up(&card->shutdown_sleep);
872                 if (card->free_on_last_close)
873                         snd_card_do_free(card);
874         }
875         if (!found) {
876                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
877                 return -ENOENT;
878         }
879         kfree(found);
880         return 0;
881 }
882
883 EXPORT_SYMBOL(snd_card_file_remove);
884
885 #ifdef CONFIG_PM
886 /**
887  *  snd_power_wait - wait until the power-state is changed.
888  *  @card: soundcard structure
889  *  @power_state: expected power state
890  *
891  *  Waits until the power-state is changed.
892  *
893  *  Note: the power lock must be active before call.
894  */
895 int snd_power_wait(struct snd_card *card, unsigned int power_state)
896 {
897         wait_queue_t wait;
898         int result = 0;
899
900         /* fastpath */
901         if (snd_power_get_state(card) == power_state)
902                 return 0;
903         init_waitqueue_entry(&wait, current);
904         add_wait_queue(&card->power_sleep, &wait);
905         while (1) {
906                 if (card->shutdown) {
907                         result = -ENODEV;
908                         break;
909                 }
910                 if (snd_power_get_state(card) == power_state)
911                         break;
912                 set_current_state(TASK_UNINTERRUPTIBLE);
913                 snd_power_unlock(card);
914                 schedule_timeout(30 * HZ);
915                 snd_power_lock(card);
916         }
917         remove_wait_queue(&card->power_sleep, &wait);
918         return result;
919 }
920
921 EXPORT_SYMBOL(snd_power_wait);
922 #endif /* CONFIG_PM */