USB: usb-storage: unusual_devs update for Super TOP SATA bridge
[linux/fpc-iii.git] / sound / core / init.c
blob7b012d15c2cf1599e92d0ddc832a6b0ece653e9e
1 /*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
22 #include <linux/init.h>
23 #include <linux/sched.h>
24 #include <linux/module.h>
25 #include <linux/device.h>
26 #include <linux/file.h>
27 #include <linux/slab.h>
28 #include <linux/time.h>
29 #include <linux/ctype.h>
30 #include <linux/pm.h>
32 #include <sound/core.h>
33 #include <sound/control.h>
34 #include <sound/info.h>
36 /* monitor files for graceful shutdown (hotplug) */
37 struct snd_monitor_file {
38 struct file *file;
39 const struct file_operations *disconnected_f_op;
40 struct list_head shutdown_list; /* still need to shutdown */
41 struct list_head list; /* link of monitor files */
44 static DEFINE_SPINLOCK(shutdown_lock);
45 static LIST_HEAD(shutdown_files);
47 static const struct file_operations snd_shutdown_f_ops;
49 static unsigned int snd_cards_lock; /* locked for registering/using */
50 struct snd_card *snd_cards[SNDRV_CARDS];
51 EXPORT_SYMBOL(snd_cards);
53 static DEFINE_MUTEX(snd_card_mutex);
55 static char *slots[SNDRV_CARDS];
56 module_param_array(slots, charp, NULL, 0444);
57 MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
59 /* return non-zero if the given index is reserved for the given
60 * module via slots option
62 static int module_slot_match(struct module *module, int idx)
64 int match = 1;
65 #ifdef MODULE
66 const char *s1, *s2;
68 if (!module || !module->name || !slots[idx])
69 return 0;
71 s1 = module->name;
72 s2 = slots[idx];
73 if (*s2 == '!') {
74 match = 0; /* negative match */
75 s2++;
77 /* compare module name strings
78 * hyphens are handled as equivalent with underscore
80 for (;;) {
81 char c1 = *s1++;
82 char c2 = *s2++;
83 if (c1 == '-')
84 c1 = '_';
85 if (c2 == '-')
86 c2 = '_';
87 if (c1 != c2)
88 return !match;
89 if (!c1)
90 break;
92 #endif /* MODULE */
93 return match;
96 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
97 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
98 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
99 #endif
101 #ifdef CONFIG_PROC_FS
102 static void snd_card_id_read(struct snd_info_entry *entry,
103 struct snd_info_buffer *buffer)
105 snd_iprintf(buffer, "%s\n", entry->card->id);
108 static inline int init_info_for_card(struct snd_card *card)
110 int err;
111 struct snd_info_entry *entry;
113 if ((err = snd_info_card_register(card)) < 0) {
114 snd_printd("unable to create card info\n");
115 return err;
117 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
118 snd_printd("unable to create card entry\n");
119 return err;
121 entry->c.text.read = snd_card_id_read;
122 if (snd_info_register(entry) < 0) {
123 snd_info_free_entry(entry);
124 entry = NULL;
126 card->proc_id = entry;
127 return 0;
129 #else /* !CONFIG_PROC_FS */
130 #define init_info_for_card(card)
131 #endif
134 * snd_card_create - create and initialize a soundcard structure
135 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
136 * @xid: card identification (ASCII string)
137 * @module: top level module for locking
138 * @extra_size: allocate this extra size after the main soundcard structure
139 * @card_ret: the pointer to store the created card instance
141 * Creates and initializes a soundcard structure.
143 * The function allocates snd_card instance via kzalloc with the given
144 * space for the driver to use freely. The allocated struct is stored
145 * in the given card_ret pointer.
147 * Returns zero if successful or a negative error code.
149 int snd_card_create(int idx, const char *xid,
150 struct module *module, int extra_size,
151 struct snd_card **card_ret)
153 struct snd_card *card;
154 int err, idx2;
156 if (snd_BUG_ON(!card_ret))
157 return -EINVAL;
158 *card_ret = NULL;
160 if (extra_size < 0)
161 extra_size = 0;
162 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
163 if (!card)
164 return -ENOMEM;
165 if (xid)
166 strlcpy(card->id, xid, sizeof(card->id));
167 err = 0;
168 mutex_lock(&snd_card_mutex);
169 if (idx < 0) {
170 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
171 /* idx == -1 == 0xffff means: take any free slot */
172 if (~snd_cards_lock & idx & 1<<idx2) {
173 if (module_slot_match(module, idx2)) {
174 idx = idx2;
175 break;
179 if (idx < 0) {
180 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
181 /* idx == -1 == 0xffff means: take any free slot */
182 if (~snd_cards_lock & idx & 1<<idx2) {
183 if (!slots[idx2] || !*slots[idx2]) {
184 idx = idx2;
185 break;
189 if (idx < 0)
190 err = -ENODEV;
191 else if (idx < snd_ecards_limit) {
192 if (snd_cards_lock & (1 << idx))
193 err = -EBUSY; /* invalid */
194 } else if (idx >= SNDRV_CARDS)
195 err = -ENODEV;
196 if (err < 0) {
197 mutex_unlock(&snd_card_mutex);
198 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
199 idx, snd_ecards_limit - 1, err);
200 goto __error;
202 snd_cards_lock |= 1 << idx; /* lock it */
203 if (idx >= snd_ecards_limit)
204 snd_ecards_limit = idx + 1; /* increase the limit */
205 mutex_unlock(&snd_card_mutex);
206 card->number = idx;
207 card->module = module;
208 INIT_LIST_HEAD(&card->devices);
209 init_rwsem(&card->controls_rwsem);
210 rwlock_init(&card->ctl_files_rwlock);
211 INIT_LIST_HEAD(&card->controls);
212 INIT_LIST_HEAD(&card->ctl_files);
213 spin_lock_init(&card->files_lock);
214 INIT_LIST_HEAD(&card->files_list);
215 init_waitqueue_head(&card->shutdown_sleep);
216 atomic_set(&card->refcount, 0);
217 #ifdef CONFIG_PM
218 mutex_init(&card->power_lock);
219 init_waitqueue_head(&card->power_sleep);
220 #endif
221 /* the control interface cannot be accessed from the user space until */
222 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
223 err = snd_ctl_create(card);
224 if (err < 0) {
225 snd_printk(KERN_ERR "unable to register control minors\n");
226 goto __error;
228 err = snd_info_card_create(card);
229 if (err < 0) {
230 snd_printk(KERN_ERR "unable to create card info\n");
231 goto __error_ctl;
233 if (extra_size > 0)
234 card->private_data = (char *)card + sizeof(struct snd_card);
235 *card_ret = card;
236 return 0;
238 __error_ctl:
239 snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
240 __error:
241 kfree(card);
242 return err;
244 EXPORT_SYMBOL(snd_card_create);
246 /* return non-zero if a card is already locked */
247 int snd_card_locked(int card)
249 int locked;
251 mutex_lock(&snd_card_mutex);
252 locked = snd_cards_lock & (1 << card);
253 mutex_unlock(&snd_card_mutex);
254 return locked;
257 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
259 return -ENODEV;
262 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
263 size_t count, loff_t *offset)
265 return -ENODEV;
268 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
269 size_t count, loff_t *offset)
271 return -ENODEV;
274 static int snd_disconnect_release(struct inode *inode, struct file *file)
276 struct snd_monitor_file *df = NULL, *_df;
278 spin_lock(&shutdown_lock);
279 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
280 if (_df->file == file) {
281 df = _df;
282 list_del_init(&df->shutdown_list);
283 break;
286 spin_unlock(&shutdown_lock);
288 if (likely(df)) {
289 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
290 df->disconnected_f_op->fasync(-1, file, 0);
291 return df->disconnected_f_op->release(inode, file);
294 panic("%s(%p, %p) failed!", __func__, inode, file);
297 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
299 return POLLERR | POLLNVAL;
302 static long snd_disconnect_ioctl(struct file *file,
303 unsigned int cmd, unsigned long arg)
305 return -ENODEV;
308 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
310 return -ENODEV;
313 static int snd_disconnect_fasync(int fd, struct file *file, int on)
315 return -ENODEV;
318 static const struct file_operations snd_shutdown_f_ops =
320 .owner = THIS_MODULE,
321 .llseek = snd_disconnect_llseek,
322 .read = snd_disconnect_read,
323 .write = snd_disconnect_write,
324 .release = snd_disconnect_release,
325 .poll = snd_disconnect_poll,
326 .unlocked_ioctl = snd_disconnect_ioctl,
327 #ifdef CONFIG_COMPAT
328 .compat_ioctl = snd_disconnect_ioctl,
329 #endif
330 .mmap = snd_disconnect_mmap,
331 .fasync = snd_disconnect_fasync
335 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
336 * @card: soundcard structure
338 * Disconnects all APIs from the file-operations (user space).
340 * Returns zero, otherwise a negative error code.
342 * Note: The current implementation replaces all active file->f_op with special
343 * dummy file operations (they do nothing except release).
345 int snd_card_disconnect(struct snd_card *card)
347 struct snd_monitor_file *mfile;
348 int err;
350 if (!card)
351 return -EINVAL;
353 spin_lock(&card->files_lock);
354 if (card->shutdown) {
355 spin_unlock(&card->files_lock);
356 return 0;
358 card->shutdown = 1;
359 spin_unlock(&card->files_lock);
361 /* phase 1: disable fops (user space) operations for ALSA API */
362 mutex_lock(&snd_card_mutex);
363 snd_cards[card->number] = NULL;
364 snd_cards_lock &= ~(1 << card->number);
365 mutex_unlock(&snd_card_mutex);
367 /* phase 2: replace file->f_op with special dummy operations */
369 spin_lock(&card->files_lock);
370 list_for_each_entry(mfile, &card->files_list, list) {
371 /* it's critical part, use endless loop */
372 /* we have no room to fail */
373 mfile->disconnected_f_op = mfile->file->f_op;
375 spin_lock(&shutdown_lock);
376 list_add(&mfile->shutdown_list, &shutdown_files);
377 spin_unlock(&shutdown_lock);
379 mfile->file->f_op = &snd_shutdown_f_ops;
380 fops_get(mfile->file->f_op);
382 spin_unlock(&card->files_lock);
384 /* phase 3: notify all connected devices about disconnection */
385 /* at this point, they cannot respond to any calls except release() */
387 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
388 if (snd_mixer_oss_notify_callback)
389 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
390 #endif
392 /* notify all devices that we are disconnected */
393 err = snd_device_disconnect_all(card);
394 if (err < 0)
395 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
397 snd_info_card_disconnect(card);
398 if (card->card_dev) {
399 device_unregister(card->card_dev);
400 card->card_dev = NULL;
402 #ifdef CONFIG_PM
403 wake_up(&card->power_sleep);
404 #endif
405 return 0;
408 EXPORT_SYMBOL(snd_card_disconnect);
411 * snd_card_free - frees given soundcard structure
412 * @card: soundcard structure
414 * This function releases the soundcard structure and the all assigned
415 * devices automatically. That is, you don't have to release the devices
416 * by yourself.
418 * Returns zero. Frees all associated devices and frees the control
419 * interface associated to given soundcard.
421 static int snd_card_do_free(struct snd_card *card)
423 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
424 if (snd_mixer_oss_notify_callback)
425 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
426 #endif
427 if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
428 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
429 /* Fatal, but this situation should never occur */
431 if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
432 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
433 /* Fatal, but this situation should never occur */
435 if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
436 snd_printk(KERN_ERR "unable to free all devices (post)\n");
437 /* Fatal, but this situation should never occur */
439 if (card->private_free)
440 card->private_free(card);
441 snd_info_free_entry(card->proc_id);
442 if (snd_info_card_free(card) < 0) {
443 snd_printk(KERN_WARNING "unable to free card info\n");
444 /* Not fatal error */
446 kfree(card);
447 return 0;
451 * snd_card_unref - release the reference counter
452 * @card: the card instance
454 * Decrements the reference counter. When it reaches to zero, wake up
455 * the sleeper and call the destructor if needed.
457 void snd_card_unref(struct snd_card *card)
459 if (atomic_dec_and_test(&card->refcount)) {
460 wake_up(&card->shutdown_sleep);
461 if (card->free_on_last_close)
462 snd_card_do_free(card);
465 EXPORT_SYMBOL(snd_card_unref);
467 int snd_card_free_when_closed(struct snd_card *card)
469 int ret;
471 atomic_inc(&card->refcount);
472 ret = snd_card_disconnect(card);
473 if (ret) {
474 atomic_dec(&card->refcount);
475 return ret;
478 card->free_on_last_close = 1;
479 if (atomic_dec_and_test(&card->refcount))
480 snd_card_do_free(card);
481 return 0;
484 EXPORT_SYMBOL(snd_card_free_when_closed);
486 int snd_card_free(struct snd_card *card)
488 int ret = snd_card_disconnect(card);
489 if (ret)
490 return ret;
492 /* wait, until all devices are ready for the free operation */
493 wait_event(card->shutdown_sleep, !atomic_read(&card->refcount));
494 snd_card_do_free(card);
495 return 0;
498 EXPORT_SYMBOL(snd_card_free);
500 /* retrieve the last word of shortname or longname */
501 static const char *retrieve_id_from_card_name(const char *name)
503 const char *spos = name;
505 while (*name) {
506 if (isspace(*name) && isalnum(name[1]))
507 spos = name + 1;
508 name++;
510 return spos;
513 /* return true if the given id string doesn't conflict any other card ids */
514 static bool card_id_ok(struct snd_card *card, const char *id)
516 int i;
517 if (!snd_info_check_reserved_words(id))
518 return false;
519 for (i = 0; i < snd_ecards_limit; i++) {
520 if (snd_cards[i] && snd_cards[i] != card &&
521 !strcmp(snd_cards[i]->id, id))
522 return false;
524 return true;
527 /* copy to card->id only with valid letters from nid */
528 static void copy_valid_id_string(struct snd_card *card, const char *src,
529 const char *nid)
531 char *id = card->id;
533 while (*nid && !isalnum(*nid))
534 nid++;
535 if (isdigit(*nid))
536 *id++ = isalpha(*src) ? *src : 'D';
537 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
538 if (isalnum(*nid))
539 *id++ = *nid;
540 nid++;
542 *id = 0;
545 /* Set card->id from the given string
546 * If the string conflicts with other ids, add a suffix to make it unique.
548 static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
549 const char *nid)
551 int len, loops;
552 bool with_suffix;
553 bool is_default = false;
554 char *id;
556 copy_valid_id_string(card, src, nid);
557 id = card->id;
559 again:
560 /* use "Default" for obviously invalid strings
561 * ("card" conflicts with proc directories)
563 if (!*id || !strncmp(id, "card", 4)) {
564 strcpy(id, "Default");
565 is_default = true;
568 with_suffix = false;
569 for (loops = 0; loops < SNDRV_CARDS; loops++) {
570 if (card_id_ok(card, id))
571 return; /* OK */
573 len = strlen(id);
574 if (!with_suffix) {
575 /* add the "_X" suffix */
576 char *spos = id + len;
577 if (len > sizeof(card->id) - 3)
578 spos = id + sizeof(card->id) - 3;
579 strcpy(spos, "_1");
580 with_suffix = true;
581 } else {
582 /* modify the existing suffix */
583 if (id[len - 1] != '9')
584 id[len - 1]++;
585 else
586 id[len - 1] = 'A';
589 /* fallback to the default id */
590 if (!is_default) {
591 *id = 0;
592 goto again;
594 /* last resort... */
595 snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
596 if (card->proc_root->name)
597 strcpy(card->id, card->proc_root->name);
601 * snd_card_set_id - set card identification name
602 * @card: soundcard structure
603 * @nid: new identification string
605 * This function sets the card identification and checks for name
606 * collisions.
608 void snd_card_set_id(struct snd_card *card, const char *nid)
610 /* check if user specified own card->id */
611 if (card->id[0] != '\0')
612 return;
613 mutex_lock(&snd_card_mutex);
614 snd_card_set_id_no_lock(card, nid, nid);
615 mutex_unlock(&snd_card_mutex);
617 EXPORT_SYMBOL(snd_card_set_id);
619 static ssize_t
620 card_id_show_attr(struct device *dev,
621 struct device_attribute *attr, char *buf)
623 struct snd_card *card = dev_get_drvdata(dev);
624 return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
627 static ssize_t
628 card_id_store_attr(struct device *dev, struct device_attribute *attr,
629 const char *buf, size_t count)
631 struct snd_card *card = dev_get_drvdata(dev);
632 char buf1[sizeof(card->id)];
633 size_t copy = count > sizeof(card->id) - 1 ?
634 sizeof(card->id) - 1 : count;
635 size_t idx;
636 int c;
638 for (idx = 0; idx < copy; idx++) {
639 c = buf[idx];
640 if (!isalnum(c) && c != '_' && c != '-')
641 return -EINVAL;
643 memcpy(buf1, buf, copy);
644 buf1[copy] = '\0';
645 mutex_lock(&snd_card_mutex);
646 if (!card_id_ok(NULL, buf1)) {
647 mutex_unlock(&snd_card_mutex);
648 return -EEXIST;
650 strcpy(card->id, buf1);
651 snd_info_card_id_change(card);
652 mutex_unlock(&snd_card_mutex);
654 return count;
657 static struct device_attribute card_id_attrs =
658 __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
660 static ssize_t
661 card_number_show_attr(struct device *dev,
662 struct device_attribute *attr, char *buf)
664 struct snd_card *card = dev_get_drvdata(dev);
665 return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
668 static struct device_attribute card_number_attrs =
669 __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
672 * snd_card_register - register the soundcard
673 * @card: soundcard structure
675 * This function registers all the devices assigned to the soundcard.
676 * Until calling this, the ALSA control interface is blocked from the
677 * external accesses. Thus, you should call this function at the end
678 * of the initialization of the card.
680 * Returns zero otherwise a negative error code if the registration failed.
682 int snd_card_register(struct snd_card *card)
684 int err;
686 if (snd_BUG_ON(!card))
687 return -EINVAL;
689 if (!card->card_dev) {
690 card->card_dev = device_create(sound_class, card->dev,
691 MKDEV(0, 0), card,
692 "card%i", card->number);
693 if (IS_ERR(card->card_dev))
694 card->card_dev = NULL;
697 if ((err = snd_device_register_all(card)) < 0)
698 return err;
699 mutex_lock(&snd_card_mutex);
700 if (snd_cards[card->number]) {
701 /* already registered */
702 mutex_unlock(&snd_card_mutex);
703 return 0;
705 if (*card->id) {
706 /* make a unique id name from the given string */
707 char tmpid[sizeof(card->id)];
708 memcpy(tmpid, card->id, sizeof(card->id));
709 snd_card_set_id_no_lock(card, tmpid, tmpid);
710 } else {
711 /* create an id from either shortname or longname */
712 const char *src;
713 src = *card->shortname ? card->shortname : card->longname;
714 snd_card_set_id_no_lock(card, src,
715 retrieve_id_from_card_name(src));
717 snd_cards[card->number] = card;
718 mutex_unlock(&snd_card_mutex);
719 init_info_for_card(card);
720 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
721 if (snd_mixer_oss_notify_callback)
722 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
723 #endif
724 if (card->card_dev) {
725 err = device_create_file(card->card_dev, &card_id_attrs);
726 if (err < 0)
727 return err;
728 err = device_create_file(card->card_dev, &card_number_attrs);
729 if (err < 0)
730 return err;
733 return 0;
736 EXPORT_SYMBOL(snd_card_register);
738 #ifdef CONFIG_PROC_FS
739 static struct snd_info_entry *snd_card_info_entry;
741 static void snd_card_info_read(struct snd_info_entry *entry,
742 struct snd_info_buffer *buffer)
744 int idx, count;
745 struct snd_card *card;
747 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
748 mutex_lock(&snd_card_mutex);
749 if ((card = snd_cards[idx]) != NULL) {
750 count++;
751 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
752 idx,
753 card->id,
754 card->driver,
755 card->shortname);
756 snd_iprintf(buffer, " %s\n",
757 card->longname);
759 mutex_unlock(&snd_card_mutex);
761 if (!count)
762 snd_iprintf(buffer, "--- no soundcards ---\n");
765 #ifdef CONFIG_SND_OSSEMUL
767 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
769 int idx, count;
770 struct snd_card *card;
772 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
773 mutex_lock(&snd_card_mutex);
774 if ((card = snd_cards[idx]) != NULL) {
775 count++;
776 snd_iprintf(buffer, "%s\n", card->longname);
778 mutex_unlock(&snd_card_mutex);
780 if (!count) {
781 snd_iprintf(buffer, "--- no soundcards ---\n");
785 #endif
787 #ifdef MODULE
788 static struct snd_info_entry *snd_card_module_info_entry;
789 static void snd_card_module_info_read(struct snd_info_entry *entry,
790 struct snd_info_buffer *buffer)
792 int idx;
793 struct snd_card *card;
795 for (idx = 0; idx < SNDRV_CARDS; idx++) {
796 mutex_lock(&snd_card_mutex);
797 if ((card = snd_cards[idx]) != NULL)
798 snd_iprintf(buffer, "%2i %s\n",
799 idx, card->module->name);
800 mutex_unlock(&snd_card_mutex);
803 #endif
805 int __init snd_card_info_init(void)
807 struct snd_info_entry *entry;
809 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
810 if (! entry)
811 return -ENOMEM;
812 entry->c.text.read = snd_card_info_read;
813 if (snd_info_register(entry) < 0) {
814 snd_info_free_entry(entry);
815 return -ENOMEM;
817 snd_card_info_entry = entry;
819 #ifdef MODULE
820 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
821 if (entry) {
822 entry->c.text.read = snd_card_module_info_read;
823 if (snd_info_register(entry) < 0)
824 snd_info_free_entry(entry);
825 else
826 snd_card_module_info_entry = entry;
828 #endif
830 return 0;
833 int __exit snd_card_info_done(void)
835 snd_info_free_entry(snd_card_info_entry);
836 #ifdef MODULE
837 snd_info_free_entry(snd_card_module_info_entry);
838 #endif
839 return 0;
842 #endif /* CONFIG_PROC_FS */
845 * snd_component_add - add a component string
846 * @card: soundcard structure
847 * @component: the component id string
849 * This function adds the component id string to the supported list.
850 * The component can be referred from the alsa-lib.
852 * Returns zero otherwise a negative error code.
855 int snd_component_add(struct snd_card *card, const char *component)
857 char *ptr;
858 int len = strlen(component);
860 ptr = strstr(card->components, component);
861 if (ptr != NULL) {
862 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
863 return 1;
865 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
866 snd_BUG();
867 return -ENOMEM;
869 if (card->components[0] != '\0')
870 strcat(card->components, " ");
871 strcat(card->components, component);
872 return 0;
875 EXPORT_SYMBOL(snd_component_add);
878 * snd_card_file_add - add the file to the file list of the card
879 * @card: soundcard structure
880 * @file: file pointer
882 * This function adds the file to the file linked-list of the card.
883 * This linked-list is used to keep tracking the connection state,
884 * and to avoid the release of busy resources by hotplug.
886 * Returns zero or a negative error code.
888 int snd_card_file_add(struct snd_card *card, struct file *file)
890 struct snd_monitor_file *mfile;
892 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
893 if (mfile == NULL)
894 return -ENOMEM;
895 mfile->file = file;
896 mfile->disconnected_f_op = NULL;
897 INIT_LIST_HEAD(&mfile->shutdown_list);
898 spin_lock(&card->files_lock);
899 if (card->shutdown) {
900 spin_unlock(&card->files_lock);
901 kfree(mfile);
902 return -ENODEV;
904 list_add(&mfile->list, &card->files_list);
905 atomic_inc(&card->refcount);
906 spin_unlock(&card->files_lock);
907 return 0;
910 EXPORT_SYMBOL(snd_card_file_add);
913 * snd_card_file_remove - remove the file from the file list
914 * @card: soundcard structure
915 * @file: file pointer
917 * This function removes the file formerly added to the card via
918 * snd_card_file_add() function.
919 * If all files are removed and snd_card_free_when_closed() was
920 * called beforehand, it processes the pending release of
921 * resources.
923 * Returns zero or a negative error code.
925 int snd_card_file_remove(struct snd_card *card, struct file *file)
927 struct snd_monitor_file *mfile, *found = NULL;
929 spin_lock(&card->files_lock);
930 list_for_each_entry(mfile, &card->files_list, list) {
931 if (mfile->file == file) {
932 list_del(&mfile->list);
933 spin_lock(&shutdown_lock);
934 list_del(&mfile->shutdown_list);
935 spin_unlock(&shutdown_lock);
936 if (mfile->disconnected_f_op)
937 fops_put(mfile->disconnected_f_op);
938 found = mfile;
939 break;
942 spin_unlock(&card->files_lock);
943 if (!found) {
944 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
945 return -ENOENT;
947 kfree(found);
948 snd_card_unref(card);
949 return 0;
952 EXPORT_SYMBOL(snd_card_file_remove);
954 #ifdef CONFIG_PM
956 * snd_power_wait - wait until the power-state is changed.
957 * @card: soundcard structure
958 * @power_state: expected power state
960 * Waits until the power-state is changed.
962 * Note: the power lock must be active before call.
964 int snd_power_wait(struct snd_card *card, unsigned int power_state)
966 wait_queue_t wait;
967 int result = 0;
969 /* fastpath */
970 if (snd_power_get_state(card) == power_state)
971 return 0;
972 init_waitqueue_entry(&wait, current);
973 add_wait_queue(&card->power_sleep, &wait);
974 while (1) {
975 if (card->shutdown) {
976 result = -ENODEV;
977 break;
979 if (snd_power_get_state(card) == power_state)
980 break;
981 set_current_state(TASK_UNINTERRUPTIBLE);
982 snd_power_unlock(card);
983 schedule_timeout(30 * HZ);
984 snd_power_lock(card);
986 remove_wait_queue(&card->power_sleep, &wait);
987 return result;
990 EXPORT_SYMBOL(snd_power_wait);
991 #endif /* CONFIG_PM */