Merge tag 'locks-v3.16-2' of git://git.samba.org/jlayton/linux
[linux/fpc-iii.git] / sound / core / init.c
blob7bdfd19e24a80aa68b9db813c2d98ea6f2bc36eb
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>
31 #include <linux/completion.h>
33 #include <sound/core.h>
34 #include <sound/control.h>
35 #include <sound/info.h>
37 /* monitor files for graceful shutdown (hotplug) */
38 struct snd_monitor_file {
39 struct file *file;
40 const struct file_operations *disconnected_f_op;
41 struct list_head shutdown_list; /* still need to shutdown */
42 struct list_head list; /* link of monitor files */
45 static DEFINE_SPINLOCK(shutdown_lock);
46 static LIST_HEAD(shutdown_files);
48 static const struct file_operations snd_shutdown_f_ops;
50 /* locked for registering/using */
51 static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
52 struct snd_card *snd_cards[SNDRV_CARDS];
53 EXPORT_SYMBOL(snd_cards);
55 static DEFINE_MUTEX(snd_card_mutex);
57 static char *slots[SNDRV_CARDS];
58 module_param_array(slots, charp, NULL, 0444);
59 MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
61 /* return non-zero if the given index is reserved for the given
62 * module via slots option
64 static int module_slot_match(struct module *module, int idx)
66 int match = 1;
67 #ifdef MODULE
68 const char *s1, *s2;
70 if (!module || !*module->name || !slots[idx])
71 return 0;
73 s1 = module->name;
74 s2 = slots[idx];
75 if (*s2 == '!') {
76 match = 0; /* negative match */
77 s2++;
79 /* compare module name strings
80 * hyphens are handled as equivalent with underscore
82 for (;;) {
83 char c1 = *s1++;
84 char c2 = *s2++;
85 if (c1 == '-')
86 c1 = '_';
87 if (c2 == '-')
88 c2 = '_';
89 if (c1 != c2)
90 return !match;
91 if (!c1)
92 break;
94 #endif /* MODULE */
95 return match;
98 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
99 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
100 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
101 #endif
103 #ifdef CONFIG_PROC_FS
104 static void snd_card_id_read(struct snd_info_entry *entry,
105 struct snd_info_buffer *buffer)
107 snd_iprintf(buffer, "%s\n", entry->card->id);
110 static inline int init_info_for_card(struct snd_card *card)
112 int err;
113 struct snd_info_entry *entry;
115 if ((err = snd_info_card_register(card)) < 0) {
116 dev_dbg(card->dev, "unable to create card info\n");
117 return err;
119 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
120 dev_dbg(card->dev, "unable to create card entry\n");
121 return err;
123 entry->c.text.read = snd_card_id_read;
124 if (snd_info_register(entry) < 0) {
125 snd_info_free_entry(entry);
126 entry = NULL;
128 card->proc_id = entry;
129 return 0;
131 #else /* !CONFIG_PROC_FS */
132 #define init_info_for_card(card)
133 #endif
135 static int check_empty_slot(struct module *module, int slot)
137 return !slots[slot] || !*slots[slot];
140 /* return an empty slot number (>= 0) found in the given bitmask @mask.
141 * @mask == -1 == 0xffffffff means: take any free slot up to 32
142 * when no slot is available, return the original @mask as is.
144 static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
145 struct module *module)
147 int slot;
149 for (slot = 0; slot < SNDRV_CARDS; slot++) {
150 if (slot < 32 && !(mask & (1U << slot)))
151 continue;
152 if (!test_bit(slot, snd_cards_lock)) {
153 if (check(module, slot))
154 return slot; /* found */
157 return mask; /* unchanged */
160 static int snd_card_do_free(struct snd_card *card);
161 static const struct attribute_group *card_dev_attr_groups[];
163 static void release_card_device(struct device *dev)
165 snd_card_do_free(dev_to_snd_card(dev));
169 * snd_card_new - create and initialize a soundcard structure
170 * @parent: the parent device object
171 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
172 * @xid: card identification (ASCII string)
173 * @module: top level module for locking
174 * @extra_size: allocate this extra size after the main soundcard structure
175 * @card_ret: the pointer to store the created card instance
177 * Creates and initializes a soundcard structure.
179 * The function allocates snd_card instance via kzalloc with the given
180 * space for the driver to use freely. The allocated struct is stored
181 * in the given card_ret pointer.
183 * Return: Zero if successful or a negative error code.
185 int snd_card_new(struct device *parent, int idx, const char *xid,
186 struct module *module, int extra_size,
187 struct snd_card **card_ret)
189 struct snd_card *card;
190 int err;
192 if (snd_BUG_ON(!card_ret))
193 return -EINVAL;
194 *card_ret = NULL;
196 if (extra_size < 0)
197 extra_size = 0;
198 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
199 if (!card)
200 return -ENOMEM;
201 if (extra_size > 0)
202 card->private_data = (char *)card + sizeof(struct snd_card);
203 if (xid)
204 strlcpy(card->id, xid, sizeof(card->id));
205 err = 0;
206 mutex_lock(&snd_card_mutex);
207 if (idx < 0) /* first check the matching module-name slot */
208 idx = get_slot_from_bitmask(idx, module_slot_match, module);
209 if (idx < 0) /* if not matched, assign an empty slot */
210 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
211 if (idx < 0)
212 err = -ENODEV;
213 else if (idx < snd_ecards_limit) {
214 if (test_bit(idx, snd_cards_lock))
215 err = -EBUSY; /* invalid */
216 } else if (idx >= SNDRV_CARDS)
217 err = -ENODEV;
218 if (err < 0) {
219 mutex_unlock(&snd_card_mutex);
220 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
221 idx, snd_ecards_limit - 1, err);
222 kfree(card);
223 return err;
225 set_bit(idx, snd_cards_lock); /* lock it */
226 if (idx >= snd_ecards_limit)
227 snd_ecards_limit = idx + 1; /* increase the limit */
228 mutex_unlock(&snd_card_mutex);
229 card->dev = parent;
230 card->number = idx;
231 card->module = module;
232 INIT_LIST_HEAD(&card->devices);
233 init_rwsem(&card->controls_rwsem);
234 rwlock_init(&card->ctl_files_rwlock);
235 mutex_init(&card->user_ctl_lock);
236 INIT_LIST_HEAD(&card->controls);
237 INIT_LIST_HEAD(&card->ctl_files);
238 spin_lock_init(&card->files_lock);
239 INIT_LIST_HEAD(&card->files_list);
240 #ifdef CONFIG_PM
241 mutex_init(&card->power_lock);
242 init_waitqueue_head(&card->power_sleep);
243 #endif
245 device_initialize(&card->card_dev);
246 card->card_dev.parent = parent;
247 card->card_dev.class = sound_class;
248 card->card_dev.release = release_card_device;
249 card->card_dev.groups = card_dev_attr_groups;
250 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
251 if (err < 0)
252 goto __error;
254 /* the control interface cannot be accessed from the user space until */
255 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
256 err = snd_ctl_create(card);
257 if (err < 0) {
258 dev_err(parent, "unable to register control minors\n");
259 goto __error;
261 err = snd_info_card_create(card);
262 if (err < 0) {
263 dev_err(parent, "unable to create card info\n");
264 goto __error_ctl;
266 *card_ret = card;
267 return 0;
269 __error_ctl:
270 snd_device_free_all(card);
271 __error:
272 put_device(&card->card_dev);
273 return err;
275 EXPORT_SYMBOL(snd_card_new);
277 /* return non-zero if a card is already locked */
278 int snd_card_locked(int card)
280 int locked;
282 mutex_lock(&snd_card_mutex);
283 locked = test_bit(card, snd_cards_lock);
284 mutex_unlock(&snd_card_mutex);
285 return locked;
288 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
290 return -ENODEV;
293 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
294 size_t count, loff_t *offset)
296 return -ENODEV;
299 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
300 size_t count, loff_t *offset)
302 return -ENODEV;
305 static int snd_disconnect_release(struct inode *inode, struct file *file)
307 struct snd_monitor_file *df = NULL, *_df;
309 spin_lock(&shutdown_lock);
310 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
311 if (_df->file == file) {
312 df = _df;
313 list_del_init(&df->shutdown_list);
314 break;
317 spin_unlock(&shutdown_lock);
319 if (likely(df)) {
320 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
321 df->disconnected_f_op->fasync(-1, file, 0);
322 return df->disconnected_f_op->release(inode, file);
325 panic("%s(%p, %p) failed!", __func__, inode, file);
328 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
330 return POLLERR | POLLNVAL;
333 static long snd_disconnect_ioctl(struct file *file,
334 unsigned int cmd, unsigned long arg)
336 return -ENODEV;
339 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
341 return -ENODEV;
344 static int snd_disconnect_fasync(int fd, struct file *file, int on)
346 return -ENODEV;
349 static const struct file_operations snd_shutdown_f_ops =
351 .owner = THIS_MODULE,
352 .llseek = snd_disconnect_llseek,
353 .read = snd_disconnect_read,
354 .write = snd_disconnect_write,
355 .release = snd_disconnect_release,
356 .poll = snd_disconnect_poll,
357 .unlocked_ioctl = snd_disconnect_ioctl,
358 #ifdef CONFIG_COMPAT
359 .compat_ioctl = snd_disconnect_ioctl,
360 #endif
361 .mmap = snd_disconnect_mmap,
362 .fasync = snd_disconnect_fasync
366 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
367 * @card: soundcard structure
369 * Disconnects all APIs from the file-operations (user space).
371 * Return: Zero, otherwise a negative error code.
373 * Note: The current implementation replaces all active file->f_op with special
374 * dummy file operations (they do nothing except release).
376 int snd_card_disconnect(struct snd_card *card)
378 struct snd_monitor_file *mfile;
379 int err;
381 if (!card)
382 return -EINVAL;
384 spin_lock(&card->files_lock);
385 if (card->shutdown) {
386 spin_unlock(&card->files_lock);
387 return 0;
389 card->shutdown = 1;
390 spin_unlock(&card->files_lock);
392 /* phase 1: disable fops (user space) operations for ALSA API */
393 mutex_lock(&snd_card_mutex);
394 snd_cards[card->number] = NULL;
395 clear_bit(card->number, snd_cards_lock);
396 mutex_unlock(&snd_card_mutex);
398 /* phase 2: replace file->f_op with special dummy operations */
400 spin_lock(&card->files_lock);
401 list_for_each_entry(mfile, &card->files_list, list) {
402 /* it's critical part, use endless loop */
403 /* we have no room to fail */
404 mfile->disconnected_f_op = mfile->file->f_op;
406 spin_lock(&shutdown_lock);
407 list_add(&mfile->shutdown_list, &shutdown_files);
408 spin_unlock(&shutdown_lock);
410 mfile->file->f_op = &snd_shutdown_f_ops;
411 fops_get(mfile->file->f_op);
413 spin_unlock(&card->files_lock);
415 /* phase 3: notify all connected devices about disconnection */
416 /* at this point, they cannot respond to any calls except release() */
418 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
419 if (snd_mixer_oss_notify_callback)
420 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
421 #endif
423 /* notify all devices that we are disconnected */
424 err = snd_device_disconnect_all(card);
425 if (err < 0)
426 dev_err(card->dev, "not all devices for card %i can be disconnected\n", card->number);
428 snd_info_card_disconnect(card);
429 if (card->registered) {
430 device_del(&card->card_dev);
431 card->registered = false;
433 #ifdef CONFIG_PM
434 wake_up(&card->power_sleep);
435 #endif
436 return 0;
439 EXPORT_SYMBOL(snd_card_disconnect);
442 * snd_card_free - frees given soundcard structure
443 * @card: soundcard structure
445 * This function releases the soundcard structure and the all assigned
446 * devices automatically. That is, you don't have to release the devices
447 * by yourself.
449 * Return: Zero. Frees all associated devices and frees the control
450 * interface associated to given soundcard.
452 static int snd_card_do_free(struct snd_card *card)
454 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
455 if (snd_mixer_oss_notify_callback)
456 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
457 #endif
458 snd_device_free_all(card);
459 if (card->private_free)
460 card->private_free(card);
461 snd_info_free_entry(card->proc_id);
462 if (snd_info_card_free(card) < 0) {
463 dev_warn(card->dev, "unable to free card info\n");
464 /* Not fatal error */
466 if (card->release_completion)
467 complete(card->release_completion);
468 kfree(card);
469 return 0;
472 int snd_card_free_when_closed(struct snd_card *card)
474 int ret = snd_card_disconnect(card);
475 if (ret)
476 return ret;
477 put_device(&card->card_dev);
478 return 0;
480 EXPORT_SYMBOL(snd_card_free_when_closed);
482 int snd_card_free(struct snd_card *card)
484 struct completion released;
485 int ret;
487 init_completion(&released);
488 card->release_completion = &released;
489 ret = snd_card_free_when_closed(card);
490 if (ret)
491 return ret;
492 /* wait, until all devices are ready for the free operation */
493 wait_for_completion(&released);
494 return 0;
496 EXPORT_SYMBOL(snd_card_free);
498 /* retrieve the last word of shortname or longname */
499 static const char *retrieve_id_from_card_name(const char *name)
501 const char *spos = name;
503 while (*name) {
504 if (isspace(*name) && isalnum(name[1]))
505 spos = name + 1;
506 name++;
508 return spos;
511 /* return true if the given id string doesn't conflict any other card ids */
512 static bool card_id_ok(struct snd_card *card, const char *id)
514 int i;
515 if (!snd_info_check_reserved_words(id))
516 return false;
517 for (i = 0; i < snd_ecards_limit; i++) {
518 if (snd_cards[i] && snd_cards[i] != card &&
519 !strcmp(snd_cards[i]->id, id))
520 return false;
522 return true;
525 /* copy to card->id only with valid letters from nid */
526 static void copy_valid_id_string(struct snd_card *card, const char *src,
527 const char *nid)
529 char *id = card->id;
531 while (*nid && !isalnum(*nid))
532 nid++;
533 if (isdigit(*nid))
534 *id++ = isalpha(*src) ? *src : 'D';
535 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
536 if (isalnum(*nid))
537 *id++ = *nid;
538 nid++;
540 *id = 0;
543 /* Set card->id from the given string
544 * If the string conflicts with other ids, add a suffix to make it unique.
546 static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
547 const char *nid)
549 int len, loops;
550 bool is_default = false;
551 char *id;
553 copy_valid_id_string(card, src, nid);
554 id = card->id;
556 again:
557 /* use "Default" for obviously invalid strings
558 * ("card" conflicts with proc directories)
560 if (!*id || !strncmp(id, "card", 4)) {
561 strcpy(id, "Default");
562 is_default = true;
565 len = strlen(id);
566 for (loops = 0; loops < SNDRV_CARDS; loops++) {
567 char *spos;
568 char sfxstr[5]; /* "_012" */
569 int sfxlen;
571 if (card_id_ok(card, id))
572 return; /* OK */
574 /* Add _XYZ suffix */
575 sprintf(sfxstr, "_%X", loops + 1);
576 sfxlen = strlen(sfxstr);
577 if (len + sfxlen >= sizeof(card->id))
578 spos = id + sizeof(card->id) - sfxlen - 1;
579 else
580 spos = id + len;
581 strcpy(spos, sfxstr);
583 /* fallback to the default id */
584 if (!is_default) {
585 *id = 0;
586 goto again;
588 /* last resort... */
589 dev_err(card->dev, "unable to set card id (%s)\n", id);
590 if (card->proc_root->name)
591 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
595 * snd_card_set_id - set card identification name
596 * @card: soundcard structure
597 * @nid: new identification string
599 * This function sets the card identification and checks for name
600 * collisions.
602 void snd_card_set_id(struct snd_card *card, const char *nid)
604 /* check if user specified own card->id */
605 if (card->id[0] != '\0')
606 return;
607 mutex_lock(&snd_card_mutex);
608 snd_card_set_id_no_lock(card, nid, nid);
609 mutex_unlock(&snd_card_mutex);
611 EXPORT_SYMBOL(snd_card_set_id);
613 static ssize_t
614 card_id_show_attr(struct device *dev,
615 struct device_attribute *attr, char *buf)
617 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
618 return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
621 static ssize_t
622 card_id_store_attr(struct device *dev, struct device_attribute *attr,
623 const char *buf, size_t count)
625 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
626 char buf1[sizeof(card->id)];
627 size_t copy = count > sizeof(card->id) - 1 ?
628 sizeof(card->id) - 1 : count;
629 size_t idx;
630 int c;
632 for (idx = 0; idx < copy; idx++) {
633 c = buf[idx];
634 if (!isalnum(c) && c != '_' && c != '-')
635 return -EINVAL;
637 memcpy(buf1, buf, copy);
638 buf1[copy] = '\0';
639 mutex_lock(&snd_card_mutex);
640 if (!card_id_ok(NULL, buf1)) {
641 mutex_unlock(&snd_card_mutex);
642 return -EEXIST;
644 strcpy(card->id, buf1);
645 snd_info_card_id_change(card);
646 mutex_unlock(&snd_card_mutex);
648 return count;
651 static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
653 static ssize_t
654 card_number_show_attr(struct device *dev,
655 struct device_attribute *attr, char *buf)
657 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
658 return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
661 static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
663 static struct attribute *card_dev_attrs[] = {
664 &dev_attr_id.attr,
665 &dev_attr_number.attr,
666 NULL
669 static struct attribute_group card_dev_attr_group = {
670 .attrs = card_dev_attrs,
673 static const struct attribute_group *card_dev_attr_groups[] = {
674 &card_dev_attr_group,
675 NULL
679 * snd_card_register - register the soundcard
680 * @card: soundcard structure
682 * This function registers all the devices assigned to the soundcard.
683 * Until calling this, the ALSA control interface is blocked from the
684 * external accesses. Thus, you should call this function at the end
685 * of the initialization of the card.
687 * Return: Zero otherwise a negative error code if the registration failed.
689 int snd_card_register(struct snd_card *card)
691 int err;
693 if (snd_BUG_ON(!card))
694 return -EINVAL;
696 if (!card->registered) {
697 err = device_add(&card->card_dev);
698 if (err < 0)
699 return err;
700 card->registered = true;
703 if ((err = snd_device_register_all(card)) < 0)
704 return err;
705 mutex_lock(&snd_card_mutex);
706 if (snd_cards[card->number]) {
707 /* already registered */
708 mutex_unlock(&snd_card_mutex);
709 return 0;
711 if (*card->id) {
712 /* make a unique id name from the given string */
713 char tmpid[sizeof(card->id)];
714 memcpy(tmpid, card->id, sizeof(card->id));
715 snd_card_set_id_no_lock(card, tmpid, tmpid);
716 } else {
717 /* create an id from either shortname or longname */
718 const char *src;
719 src = *card->shortname ? card->shortname : card->longname;
720 snd_card_set_id_no_lock(card, src,
721 retrieve_id_from_card_name(src));
723 snd_cards[card->number] = card;
724 mutex_unlock(&snd_card_mutex);
725 init_info_for_card(card);
726 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
727 if (snd_mixer_oss_notify_callback)
728 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
729 #endif
730 return 0;
733 EXPORT_SYMBOL(snd_card_register);
735 #ifdef CONFIG_PROC_FS
736 static struct snd_info_entry *snd_card_info_entry;
738 static void snd_card_info_read(struct snd_info_entry *entry,
739 struct snd_info_buffer *buffer)
741 int idx, count;
742 struct snd_card *card;
744 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
745 mutex_lock(&snd_card_mutex);
746 if ((card = snd_cards[idx]) != NULL) {
747 count++;
748 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
749 idx,
750 card->id,
751 card->driver,
752 card->shortname);
753 snd_iprintf(buffer, " %s\n",
754 card->longname);
756 mutex_unlock(&snd_card_mutex);
758 if (!count)
759 snd_iprintf(buffer, "--- no soundcards ---\n");
762 #ifdef CONFIG_SND_OSSEMUL
764 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
766 int idx, count;
767 struct snd_card *card;
769 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
770 mutex_lock(&snd_card_mutex);
771 if ((card = snd_cards[idx]) != NULL) {
772 count++;
773 snd_iprintf(buffer, "%s\n", card->longname);
775 mutex_unlock(&snd_card_mutex);
777 if (!count) {
778 snd_iprintf(buffer, "--- no soundcards ---\n");
782 #endif
784 #ifdef MODULE
785 static struct snd_info_entry *snd_card_module_info_entry;
786 static void snd_card_module_info_read(struct snd_info_entry *entry,
787 struct snd_info_buffer *buffer)
789 int idx;
790 struct snd_card *card;
792 for (idx = 0; idx < SNDRV_CARDS; idx++) {
793 mutex_lock(&snd_card_mutex);
794 if ((card = snd_cards[idx]) != NULL)
795 snd_iprintf(buffer, "%2i %s\n",
796 idx, card->module->name);
797 mutex_unlock(&snd_card_mutex);
800 #endif
802 int __init snd_card_info_init(void)
804 struct snd_info_entry *entry;
806 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
807 if (! entry)
808 return -ENOMEM;
809 entry->c.text.read = snd_card_info_read;
810 if (snd_info_register(entry) < 0) {
811 snd_info_free_entry(entry);
812 return -ENOMEM;
814 snd_card_info_entry = entry;
816 #ifdef MODULE
817 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
818 if (entry) {
819 entry->c.text.read = snd_card_module_info_read;
820 if (snd_info_register(entry) < 0)
821 snd_info_free_entry(entry);
822 else
823 snd_card_module_info_entry = entry;
825 #endif
827 return 0;
830 int __exit snd_card_info_done(void)
832 snd_info_free_entry(snd_card_info_entry);
833 #ifdef MODULE
834 snd_info_free_entry(snd_card_module_info_entry);
835 #endif
836 return 0;
839 #endif /* CONFIG_PROC_FS */
842 * snd_component_add - add a component string
843 * @card: soundcard structure
844 * @component: the component id string
846 * This function adds the component id string to the supported list.
847 * The component can be referred from the alsa-lib.
849 * Return: Zero otherwise a negative error code.
852 int snd_component_add(struct snd_card *card, const char *component)
854 char *ptr;
855 int len = strlen(component);
857 ptr = strstr(card->components, component);
858 if (ptr != NULL) {
859 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
860 return 1;
862 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
863 snd_BUG();
864 return -ENOMEM;
866 if (card->components[0] != '\0')
867 strcat(card->components, " ");
868 strcat(card->components, component);
869 return 0;
872 EXPORT_SYMBOL(snd_component_add);
875 * snd_card_file_add - add the file to the file list of the card
876 * @card: soundcard structure
877 * @file: file pointer
879 * This function adds the file to the file linked-list of the card.
880 * This linked-list is used to keep tracking the connection state,
881 * and to avoid the release of busy resources by hotplug.
883 * Return: zero or a negative error code.
885 int snd_card_file_add(struct snd_card *card, struct file *file)
887 struct snd_monitor_file *mfile;
889 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
890 if (mfile == NULL)
891 return -ENOMEM;
892 mfile->file = file;
893 mfile->disconnected_f_op = NULL;
894 INIT_LIST_HEAD(&mfile->shutdown_list);
895 spin_lock(&card->files_lock);
896 if (card->shutdown) {
897 spin_unlock(&card->files_lock);
898 kfree(mfile);
899 return -ENODEV;
901 list_add(&mfile->list, &card->files_list);
902 get_device(&card->card_dev);
903 spin_unlock(&card->files_lock);
904 return 0;
907 EXPORT_SYMBOL(snd_card_file_add);
910 * snd_card_file_remove - remove the file from the file list
911 * @card: soundcard structure
912 * @file: file pointer
914 * This function removes the file formerly added to the card via
915 * snd_card_file_add() function.
916 * If all files are removed and snd_card_free_when_closed() was
917 * called beforehand, it processes the pending release of
918 * resources.
920 * Return: Zero or a negative error code.
922 int snd_card_file_remove(struct snd_card *card, struct file *file)
924 struct snd_monitor_file *mfile, *found = NULL;
926 spin_lock(&card->files_lock);
927 list_for_each_entry(mfile, &card->files_list, list) {
928 if (mfile->file == file) {
929 list_del(&mfile->list);
930 spin_lock(&shutdown_lock);
931 list_del(&mfile->shutdown_list);
932 spin_unlock(&shutdown_lock);
933 if (mfile->disconnected_f_op)
934 fops_put(mfile->disconnected_f_op);
935 found = mfile;
936 break;
939 spin_unlock(&card->files_lock);
940 if (!found) {
941 dev_err(card->dev, "card file remove problem (%p)\n", file);
942 return -ENOENT;
944 kfree(found);
945 put_device(&card->card_dev);
946 return 0;
949 EXPORT_SYMBOL(snd_card_file_remove);
951 #ifdef CONFIG_PM
953 * snd_power_wait - wait until the power-state is changed.
954 * @card: soundcard structure
955 * @power_state: expected power state
957 * Waits until the power-state is changed.
959 * Return: Zero if successful, or a negative error code.
961 * Note: the power lock must be active before call.
963 int snd_power_wait(struct snd_card *card, unsigned int power_state)
965 wait_queue_t wait;
966 int result = 0;
968 /* fastpath */
969 if (snd_power_get_state(card) == power_state)
970 return 0;
971 init_waitqueue_entry(&wait, current);
972 add_wait_queue(&card->power_sleep, &wait);
973 while (1) {
974 if (card->shutdown) {
975 result = -ENODEV;
976 break;
978 if (snd_power_get_state(card) == power_state)
979 break;
980 set_current_state(TASK_UNINTERRUPTIBLE);
981 snd_power_unlock(card);
982 schedule_timeout(30 * HZ);
983 snd_power_lock(card);
985 remove_wait_queue(&card->power_sleep, &wait);
986 return result;
989 EXPORT_SYMBOL(snd_power_wait);
990 #endif /* CONFIG_PM */