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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Initialization routines
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/init.h>
8#include <linux/sched.h>
9#include <linux/module.h>
10#include <linux/device.h>
11#include <linux/file.h>
12#include <linux/slab.h>
13#include <linux/time.h>
14#include <linux/ctype.h>
15#include <linux/pm.h>
16#include <linux/completion.h>
17
18#include <sound/core.h>
19#include <sound/control.h>
20#include <sound/info.h>
21
22/* monitor files for graceful shutdown (hotplug) */
23struct snd_monitor_file {
24 struct file *file;
25 const struct file_operations *disconnected_f_op;
26 struct list_head shutdown_list; /* still need to shutdown */
27 struct list_head list; /* link of monitor files */
28};
29
30static DEFINE_SPINLOCK(shutdown_lock);
31static LIST_HEAD(shutdown_files);
32
33static const struct file_operations snd_shutdown_f_ops;
34
35/* locked for registering/using */
36static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
37static struct snd_card *snd_cards[SNDRV_CARDS];
38
39static DEFINE_MUTEX(snd_card_mutex);
40
41static char *slots[SNDRV_CARDS];
42module_param_array(slots, charp, NULL, 0444);
43MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
44
45/* return non-zero if the given index is reserved for the given
46 * module via slots option
47 */
48static int module_slot_match(struct module *module, int idx)
49{
50 int match = 1;
51#ifdef MODULE
52 const char *s1, *s2;
53
54 if (!module || !*module->name || !slots[idx])
55 return 0;
56
57 s1 = module->name;
58 s2 = slots[idx];
59 if (*s2 == '!') {
60 match = 0; /* negative match */
61 s2++;
62 }
63 /* compare module name strings
64 * hyphens are handled as equivalent with underscore
65 */
66 for (;;) {
67 char c1 = *s1++;
68 char c2 = *s2++;
69 if (c1 == '-')
70 c1 = '_';
71 if (c2 == '-')
72 c2 = '_';
73 if (c1 != c2)
74 return !match;
75 if (!c1)
76 break;
77 }
78#endif /* MODULE */
79 return match;
80}
81
82#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
83int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
84EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
85#endif
86
87static int check_empty_slot(struct module *module, int slot)
88{
89 return !slots[slot] || !*slots[slot];
90}
91
92/* return an empty slot number (>= 0) found in the given bitmask @mask.
93 * @mask == -1 == 0xffffffff means: take any free slot up to 32
94 * when no slot is available, return the original @mask as is.
95 */
96static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
97 struct module *module)
98{
99 int slot;
100
101 for (slot = 0; slot < SNDRV_CARDS; slot++) {
102 if (slot < 32 && !(mask & (1U << slot)))
103 continue;
104 if (!test_bit(slot, snd_cards_lock)) {
105 if (check(module, slot))
106 return slot; /* found */
107 }
108 }
109 return mask; /* unchanged */
110}
111
112/* the default release callback set in snd_device_initialize() below;
113 * this is just NOP for now, as almost all jobs are already done in
114 * dev_free callback of snd_device chain instead.
115 */
116static void default_release(struct device *dev)
117{
118}
119
120/**
121 * snd_device_initialize - Initialize struct device for sound devices
122 * @dev: device to initialize
123 * @card: card to assign, optional
124 */
125void snd_device_initialize(struct device *dev, struct snd_card *card)
126{
127 device_initialize(dev);
128 if (card)
129 dev->parent = &card->card_dev;
130 dev->class = sound_class;
131 dev->release = default_release;
132}
133EXPORT_SYMBOL_GPL(snd_device_initialize);
134
135static int snd_card_do_free(struct snd_card *card);
136static const struct attribute_group card_dev_attr_group;
137
138static void release_card_device(struct device *dev)
139{
140 snd_card_do_free(dev_to_snd_card(dev));
141}
142
143/**
144 * snd_card_new - create and initialize a soundcard structure
145 * @parent: the parent device object
146 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
147 * @xid: card identification (ASCII string)
148 * @module: top level module for locking
149 * @extra_size: allocate this extra size after the main soundcard structure
150 * @card_ret: the pointer to store the created card instance
151 *
152 * Creates and initializes a soundcard structure.
153 *
154 * The function allocates snd_card instance via kzalloc with the given
155 * space for the driver to use freely. The allocated struct is stored
156 * in the given card_ret pointer.
157 *
158 * Return: Zero if successful or a negative error code.
159 */
160int snd_card_new(struct device *parent, int idx, const char *xid,
161 struct module *module, int extra_size,
162 struct snd_card **card_ret)
163{
164 struct snd_card *card;
165 int err;
166
167 if (snd_BUG_ON(!card_ret))
168 return -EINVAL;
169 *card_ret = NULL;
170
171 if (extra_size < 0)
172 extra_size = 0;
173 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
174 if (!card)
175 return -ENOMEM;
176 if (extra_size > 0)
177 card->private_data = (char *)card + sizeof(struct snd_card);
178 if (xid)
179 strlcpy(card->id, xid, sizeof(card->id));
180 err = 0;
181 mutex_lock(&snd_card_mutex);
182 if (idx < 0) /* first check the matching module-name slot */
183 idx = get_slot_from_bitmask(idx, module_slot_match, module);
184 if (idx < 0) /* if not matched, assign an empty slot */
185 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
186 if (idx < 0)
187 err = -ENODEV;
188 else if (idx < snd_ecards_limit) {
189 if (test_bit(idx, snd_cards_lock))
190 err = -EBUSY; /* invalid */
191 } else if (idx >= SNDRV_CARDS)
192 err = -ENODEV;
193 if (err < 0) {
194 mutex_unlock(&snd_card_mutex);
195 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
196 idx, snd_ecards_limit - 1, err);
197 kfree(card);
198 return err;
199 }
200 set_bit(idx, snd_cards_lock); /* lock it */
201 if (idx >= snd_ecards_limit)
202 snd_ecards_limit = idx + 1; /* increase the limit */
203 mutex_unlock(&snd_card_mutex);
204 card->dev = parent;
205 card->number = idx;
206 card->module = module;
207 INIT_LIST_HEAD(&card->devices);
208 init_rwsem(&card->controls_rwsem);
209 rwlock_init(&card->ctl_files_rwlock);
210 INIT_LIST_HEAD(&card->controls);
211 INIT_LIST_HEAD(&card->ctl_files);
212 spin_lock_init(&card->files_lock);
213 INIT_LIST_HEAD(&card->files_list);
214#ifdef CONFIG_PM
215 init_waitqueue_head(&card->power_sleep);
216#endif
217 init_waitqueue_head(&card->remove_sleep);
218
219 device_initialize(&card->card_dev);
220 card->card_dev.parent = parent;
221 card->card_dev.class = sound_class;
222 card->card_dev.release = release_card_device;
223 card->card_dev.groups = card->dev_groups;
224 card->dev_groups[0] = &card_dev_attr_group;
225 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
226 if (err < 0)
227 goto __error;
228
229 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
230 dev_driver_string(card->dev), dev_name(&card->card_dev));
231
232 /* the control interface cannot be accessed from the user space until */
233 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
234 err = snd_ctl_create(card);
235 if (err < 0) {
236 dev_err(parent, "unable to register control minors\n");
237 goto __error;
238 }
239 err = snd_info_card_create(card);
240 if (err < 0) {
241 dev_err(parent, "unable to create card info\n");
242 goto __error_ctl;
243 }
244 *card_ret = card;
245 return 0;
246
247 __error_ctl:
248 snd_device_free_all(card);
249 __error:
250 put_device(&card->card_dev);
251 return err;
252}
253EXPORT_SYMBOL(snd_card_new);
254
255/**
256 * snd_card_ref - Get the card object from the index
257 * @idx: the card index
258 *
259 * Returns a card object corresponding to the given index or NULL if not found.
260 * Release the object via snd_card_unref().
261 */
262struct snd_card *snd_card_ref(int idx)
263{
264 struct snd_card *card;
265
266 mutex_lock(&snd_card_mutex);
267 card = snd_cards[idx];
268 if (card)
269 get_device(&card->card_dev);
270 mutex_unlock(&snd_card_mutex);
271 return card;
272}
273EXPORT_SYMBOL_GPL(snd_card_ref);
274
275/* return non-zero if a card is already locked */
276int snd_card_locked(int card)
277{
278 int locked;
279
280 mutex_lock(&snd_card_mutex);
281 locked = test_bit(card, snd_cards_lock);
282 mutex_unlock(&snd_card_mutex);
283 return locked;
284}
285
286static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
287{
288 return -ENODEV;
289}
290
291static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
292 size_t count, loff_t *offset)
293{
294 return -ENODEV;
295}
296
297static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
298 size_t count, loff_t *offset)
299{
300 return -ENODEV;
301}
302
303static int snd_disconnect_release(struct inode *inode, struct file *file)
304{
305 struct snd_monitor_file *df = NULL, *_df;
306
307 spin_lock(&shutdown_lock);
308 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
309 if (_df->file == file) {
310 df = _df;
311 list_del_init(&df->shutdown_list);
312 break;
313 }
314 }
315 spin_unlock(&shutdown_lock);
316
317 if (likely(df)) {
318 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
319 df->disconnected_f_op->fasync(-1, file, 0);
320 return df->disconnected_f_op->release(inode, file);
321 }
322
323 panic("%s(%p, %p) failed!", __func__, inode, file);
324}
325
326static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
327{
328 return EPOLLERR | EPOLLNVAL;
329}
330
331static long snd_disconnect_ioctl(struct file *file,
332 unsigned int cmd, unsigned long arg)
333{
334 return -ENODEV;
335}
336
337static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
338{
339 return -ENODEV;
340}
341
342static int snd_disconnect_fasync(int fd, struct file *file, int on)
343{
344 return -ENODEV;
345}
346
347static const struct file_operations snd_shutdown_f_ops =
348{
349 .owner = THIS_MODULE,
350 .llseek = snd_disconnect_llseek,
351 .read = snd_disconnect_read,
352 .write = snd_disconnect_write,
353 .release = snd_disconnect_release,
354 .poll = snd_disconnect_poll,
355 .unlocked_ioctl = snd_disconnect_ioctl,
356#ifdef CONFIG_COMPAT
357 .compat_ioctl = snd_disconnect_ioctl,
358#endif
359 .mmap = snd_disconnect_mmap,
360 .fasync = snd_disconnect_fasync
361};
362
363/**
364 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
365 * @card: soundcard structure
366 *
367 * Disconnects all APIs from the file-operations (user space).
368 *
369 * Return: Zero, otherwise a negative error code.
370 *
371 * Note: The current implementation replaces all active file->f_op with special
372 * dummy file operations (they do nothing except release).
373 */
374int snd_card_disconnect(struct snd_card *card)
375{
376 struct snd_monitor_file *mfile;
377
378 if (!card)
379 return -EINVAL;
380
381 spin_lock(&card->files_lock);
382 if (card->shutdown) {
383 spin_unlock(&card->files_lock);
384 return 0;
385 }
386 card->shutdown = 1;
387 spin_unlock(&card->files_lock);
388
389 /* replace file->f_op with special dummy operations */
390 spin_lock(&card->files_lock);
391 list_for_each_entry(mfile, &card->files_list, list) {
392 /* it's critical part, use endless loop */
393 /* we have no room to fail */
394 mfile->disconnected_f_op = mfile->file->f_op;
395
396 spin_lock(&shutdown_lock);
397 list_add(&mfile->shutdown_list, &shutdown_files);
398 spin_unlock(&shutdown_lock);
399
400 mfile->file->f_op = &snd_shutdown_f_ops;
401 fops_get(mfile->file->f_op);
402 }
403 spin_unlock(&card->files_lock);
404
405 /* notify all connected devices about disconnection */
406 /* at this point, they cannot respond to any calls except release() */
407
408#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
409 if (snd_mixer_oss_notify_callback)
410 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
411#endif
412
413 /* notify all devices that we are disconnected */
414 snd_device_disconnect_all(card);
415
416 snd_info_card_disconnect(card);
417 if (card->registered) {
418 device_del(&card->card_dev);
419 card->registered = false;
420 }
421
422 /* disable fops (user space) operations for ALSA API */
423 mutex_lock(&snd_card_mutex);
424 snd_cards[card->number] = NULL;
425 clear_bit(card->number, snd_cards_lock);
426 mutex_unlock(&snd_card_mutex);
427
428#ifdef CONFIG_PM
429 wake_up(&card->power_sleep);
430#endif
431 return 0;
432}
433EXPORT_SYMBOL(snd_card_disconnect);
434
435/**
436 * snd_card_disconnect_sync - disconnect card and wait until files get closed
437 * @card: card object to disconnect
438 *
439 * This calls snd_card_disconnect() for disconnecting all belonging components
440 * and waits until all pending files get closed.
441 * It assures that all accesses from user-space finished so that the driver
442 * can release its resources gracefully.
443 */
444void snd_card_disconnect_sync(struct snd_card *card)
445{
446 int err;
447
448 err = snd_card_disconnect(card);
449 if (err < 0) {
450 dev_err(card->dev,
451 "snd_card_disconnect error (%d), skipping sync\n",
452 err);
453 return;
454 }
455
456 spin_lock_irq(&card->files_lock);
457 wait_event_lock_irq(card->remove_sleep,
458 list_empty(&card->files_list),
459 card->files_lock);
460 spin_unlock_irq(&card->files_lock);
461}
462EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
463
464static int snd_card_do_free(struct snd_card *card)
465{
466#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
467 if (snd_mixer_oss_notify_callback)
468 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
469#endif
470 snd_device_free_all(card);
471 if (card->private_free)
472 card->private_free(card);
473 if (snd_info_card_free(card) < 0) {
474 dev_warn(card->dev, "unable to free card info\n");
475 /* Not fatal error */
476 }
477 if (card->release_completion)
478 complete(card->release_completion);
479 kfree(card);
480 return 0;
481}
482
483/**
484 * snd_card_free_when_closed - Disconnect the card, free it later eventually
485 * @card: soundcard structure
486 *
487 * Unlike snd_card_free(), this function doesn't try to release the card
488 * resource immediately, but tries to disconnect at first. When the card
489 * is still in use, the function returns before freeing the resources.
490 * The card resources will be freed when the refcount gets to zero.
491 */
492int snd_card_free_when_closed(struct snd_card *card)
493{
494 int ret = snd_card_disconnect(card);
495 if (ret)
496 return ret;
497 put_device(&card->card_dev);
498 return 0;
499}
500EXPORT_SYMBOL(snd_card_free_when_closed);
501
502/**
503 * snd_card_free - frees given soundcard structure
504 * @card: soundcard structure
505 *
506 * This function releases the soundcard structure and the all assigned
507 * devices automatically. That is, you don't have to release the devices
508 * by yourself.
509 *
510 * This function waits until the all resources are properly released.
511 *
512 * Return: Zero. Frees all associated devices and frees the control
513 * interface associated to given soundcard.
514 */
515int snd_card_free(struct snd_card *card)
516{
517 struct completion released;
518 int ret;
519
520 init_completion(&released);
521 card->release_completion = &released;
522 ret = snd_card_free_when_closed(card);
523 if (ret)
524 return ret;
525 /* wait, until all devices are ready for the free operation */
526 wait_for_completion(&released);
527 return 0;
528}
529EXPORT_SYMBOL(snd_card_free);
530
531/* retrieve the last word of shortname or longname */
532static const char *retrieve_id_from_card_name(const char *name)
533{
534 const char *spos = name;
535
536 while (*name) {
537 if (isspace(*name) && isalnum(name[1]))
538 spos = name + 1;
539 name++;
540 }
541 return spos;
542}
543
544/* return true if the given id string doesn't conflict any other card ids */
545static bool card_id_ok(struct snd_card *card, const char *id)
546{
547 int i;
548 if (!snd_info_check_reserved_words(id))
549 return false;
550 for (i = 0; i < snd_ecards_limit; i++) {
551 if (snd_cards[i] && snd_cards[i] != card &&
552 !strcmp(snd_cards[i]->id, id))
553 return false;
554 }
555 return true;
556}
557
558/* copy to card->id only with valid letters from nid */
559static void copy_valid_id_string(struct snd_card *card, const char *src,
560 const char *nid)
561{
562 char *id = card->id;
563
564 while (*nid && !isalnum(*nid))
565 nid++;
566 if (isdigit(*nid))
567 *id++ = isalpha(*src) ? *src : 'D';
568 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
569 if (isalnum(*nid))
570 *id++ = *nid;
571 nid++;
572 }
573 *id = 0;
574}
575
576/* Set card->id from the given string
577 * If the string conflicts with other ids, add a suffix to make it unique.
578 */
579static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
580 const char *nid)
581{
582 int len, loops;
583 bool is_default = false;
584 char *id;
585
586 copy_valid_id_string(card, src, nid);
587 id = card->id;
588
589 again:
590 /* use "Default" for obviously invalid strings
591 * ("card" conflicts with proc directories)
592 */
593 if (!*id || !strncmp(id, "card", 4)) {
594 strcpy(id, "Default");
595 is_default = true;
596 }
597
598 len = strlen(id);
599 for (loops = 0; loops < SNDRV_CARDS; loops++) {
600 char *spos;
601 char sfxstr[5]; /* "_012" */
602 int sfxlen;
603
604 if (card_id_ok(card, id))
605 return; /* OK */
606
607 /* Add _XYZ suffix */
608 sprintf(sfxstr, "_%X", loops + 1);
609 sfxlen = strlen(sfxstr);
610 if (len + sfxlen >= sizeof(card->id))
611 spos = id + sizeof(card->id) - sfxlen - 1;
612 else
613 spos = id + len;
614 strcpy(spos, sfxstr);
615 }
616 /* fallback to the default id */
617 if (!is_default) {
618 *id = 0;
619 goto again;
620 }
621 /* last resort... */
622 dev_err(card->dev, "unable to set card id (%s)\n", id);
623 if (card->proc_root->name)
624 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
625}
626
627/**
628 * snd_card_set_id - set card identification name
629 * @card: soundcard structure
630 * @nid: new identification string
631 *
632 * This function sets the card identification and checks for name
633 * collisions.
634 */
635void snd_card_set_id(struct snd_card *card, const char *nid)
636{
637 /* check if user specified own card->id */
638 if (card->id[0] != '\0')
639 return;
640 mutex_lock(&snd_card_mutex);
641 snd_card_set_id_no_lock(card, nid, nid);
642 mutex_unlock(&snd_card_mutex);
643}
644EXPORT_SYMBOL(snd_card_set_id);
645
646static ssize_t
647card_id_show_attr(struct device *dev,
648 struct device_attribute *attr, char *buf)
649{
650 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
651 return scnprintf(buf, PAGE_SIZE, "%s\n", card->id);
652}
653
654static ssize_t
655card_id_store_attr(struct device *dev, struct device_attribute *attr,
656 const char *buf, size_t count)
657{
658 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
659 char buf1[sizeof(card->id)];
660 size_t copy = count > sizeof(card->id) - 1 ?
661 sizeof(card->id) - 1 : count;
662 size_t idx;
663 int c;
664
665 for (idx = 0; idx < copy; idx++) {
666 c = buf[idx];
667 if (!isalnum(c) && c != '_' && c != '-')
668 return -EINVAL;
669 }
670 memcpy(buf1, buf, copy);
671 buf1[copy] = '\0';
672 mutex_lock(&snd_card_mutex);
673 if (!card_id_ok(NULL, buf1)) {
674 mutex_unlock(&snd_card_mutex);
675 return -EEXIST;
676 }
677 strcpy(card->id, buf1);
678 snd_info_card_id_change(card);
679 mutex_unlock(&snd_card_mutex);
680
681 return count;
682}
683
684static DEVICE_ATTR(id, 0644, card_id_show_attr, card_id_store_attr);
685
686static ssize_t
687card_number_show_attr(struct device *dev,
688 struct device_attribute *attr, char *buf)
689{
690 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
691 return scnprintf(buf, PAGE_SIZE, "%i\n", card->number);
692}
693
694static DEVICE_ATTR(number, 0444, card_number_show_attr, NULL);
695
696static struct attribute *card_dev_attrs[] = {
697 &dev_attr_id.attr,
698 &dev_attr_number.attr,
699 NULL
700};
701
702static const struct attribute_group card_dev_attr_group = {
703 .attrs = card_dev_attrs,
704};
705
706/**
707 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
708 * @card: card instance
709 * @group: attribute group to append
710 */
711int snd_card_add_dev_attr(struct snd_card *card,
712 const struct attribute_group *group)
713{
714 int i;
715
716 /* loop for (arraysize-1) here to keep NULL at the last entry */
717 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
718 if (!card->dev_groups[i]) {
719 card->dev_groups[i] = group;
720 return 0;
721 }
722 }
723
724 dev_err(card->dev, "Too many groups assigned\n");
725 return -ENOSPC;
726}
727EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
728
729/**
730 * snd_card_register - register the soundcard
731 * @card: soundcard structure
732 *
733 * This function registers all the devices assigned to the soundcard.
734 * Until calling this, the ALSA control interface is blocked from the
735 * external accesses. Thus, you should call this function at the end
736 * of the initialization of the card.
737 *
738 * Return: Zero otherwise a negative error code if the registration failed.
739 */
740int snd_card_register(struct snd_card *card)
741{
742 int err;
743
744 if (snd_BUG_ON(!card))
745 return -EINVAL;
746
747 if (!card->registered) {
748 err = device_add(&card->card_dev);
749 if (err < 0)
750 return err;
751 card->registered = true;
752 }
753
754 if ((err = snd_device_register_all(card)) < 0)
755 return err;
756 mutex_lock(&snd_card_mutex);
757 if (snd_cards[card->number]) {
758 /* already registered */
759 mutex_unlock(&snd_card_mutex);
760 return snd_info_card_register(card); /* register pending info */
761 }
762 if (*card->id) {
763 /* make a unique id name from the given string */
764 char tmpid[sizeof(card->id)];
765 memcpy(tmpid, card->id, sizeof(card->id));
766 snd_card_set_id_no_lock(card, tmpid, tmpid);
767 } else {
768 /* create an id from either shortname or longname */
769 const char *src;
770 src = *card->shortname ? card->shortname : card->longname;
771 snd_card_set_id_no_lock(card, src,
772 retrieve_id_from_card_name(src));
773 }
774 snd_cards[card->number] = card;
775 mutex_unlock(&snd_card_mutex);
776 err = snd_info_card_register(card);
777 if (err < 0)
778 return err;
779
780#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
781 if (snd_mixer_oss_notify_callback)
782 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
783#endif
784 return 0;
785}
786EXPORT_SYMBOL(snd_card_register);
787
788#ifdef CONFIG_SND_PROC_FS
789static void snd_card_info_read(struct snd_info_entry *entry,
790 struct snd_info_buffer *buffer)
791{
792 int idx, count;
793 struct snd_card *card;
794
795 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
796 mutex_lock(&snd_card_mutex);
797 if ((card = snd_cards[idx]) != NULL) {
798 count++;
799 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
800 idx,
801 card->id,
802 card->driver,
803 card->shortname);
804 snd_iprintf(buffer, " %s\n",
805 card->longname);
806 }
807 mutex_unlock(&snd_card_mutex);
808 }
809 if (!count)
810 snd_iprintf(buffer, "--- no soundcards ---\n");
811}
812
813#ifdef CONFIG_SND_OSSEMUL
814void snd_card_info_read_oss(struct snd_info_buffer *buffer)
815{
816 int idx, count;
817 struct snd_card *card;
818
819 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
820 mutex_lock(&snd_card_mutex);
821 if ((card = snd_cards[idx]) != NULL) {
822 count++;
823 snd_iprintf(buffer, "%s\n", card->longname);
824 }
825 mutex_unlock(&snd_card_mutex);
826 }
827 if (!count) {
828 snd_iprintf(buffer, "--- no soundcards ---\n");
829 }
830}
831
832#endif
833
834#ifdef MODULE
835static void snd_card_module_info_read(struct snd_info_entry *entry,
836 struct snd_info_buffer *buffer)
837{
838 int idx;
839 struct snd_card *card;
840
841 for (idx = 0; idx < SNDRV_CARDS; idx++) {
842 mutex_lock(&snd_card_mutex);
843 if ((card = snd_cards[idx]) != NULL)
844 snd_iprintf(buffer, "%2i %s\n",
845 idx, card->module->name);
846 mutex_unlock(&snd_card_mutex);
847 }
848}
849#endif
850
851int __init snd_card_info_init(void)
852{
853 struct snd_info_entry *entry;
854
855 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
856 if (! entry)
857 return -ENOMEM;
858 entry->c.text.read = snd_card_info_read;
859 if (snd_info_register(entry) < 0)
860 return -ENOMEM; /* freed in error path */
861
862#ifdef MODULE
863 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
864 if (!entry)
865 return -ENOMEM;
866 entry->c.text.read = snd_card_module_info_read;
867 if (snd_info_register(entry) < 0)
868 return -ENOMEM; /* freed in error path */
869#endif
870
871 return 0;
872}
873#endif /* CONFIG_SND_PROC_FS */
874
875/**
876 * snd_component_add - add a component string
877 * @card: soundcard structure
878 * @component: the component id string
879 *
880 * This function adds the component id string to the supported list.
881 * The component can be referred from the alsa-lib.
882 *
883 * Return: Zero otherwise a negative error code.
884 */
885
886int snd_component_add(struct snd_card *card, const char *component)
887{
888 char *ptr;
889 int len = strlen(component);
890
891 ptr = strstr(card->components, component);
892 if (ptr != NULL) {
893 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
894 return 1;
895 }
896 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
897 snd_BUG();
898 return -ENOMEM;
899 }
900 if (card->components[0] != '\0')
901 strcat(card->components, " ");
902 strcat(card->components, component);
903 return 0;
904}
905EXPORT_SYMBOL(snd_component_add);
906
907/**
908 * snd_card_file_add - add the file to the file list of the card
909 * @card: soundcard structure
910 * @file: file pointer
911 *
912 * This function adds the file to the file linked-list of the card.
913 * This linked-list is used to keep tracking the connection state,
914 * and to avoid the release of busy resources by hotplug.
915 *
916 * Return: zero or a negative error code.
917 */
918int snd_card_file_add(struct snd_card *card, struct file *file)
919{
920 struct snd_monitor_file *mfile;
921
922 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
923 if (mfile == NULL)
924 return -ENOMEM;
925 mfile->file = file;
926 mfile->disconnected_f_op = NULL;
927 INIT_LIST_HEAD(&mfile->shutdown_list);
928 spin_lock(&card->files_lock);
929 if (card->shutdown) {
930 spin_unlock(&card->files_lock);
931 kfree(mfile);
932 return -ENODEV;
933 }
934 list_add(&mfile->list, &card->files_list);
935 get_device(&card->card_dev);
936 spin_unlock(&card->files_lock);
937 return 0;
938}
939EXPORT_SYMBOL(snd_card_file_add);
940
941/**
942 * snd_card_file_remove - remove the file from the file list
943 * @card: soundcard structure
944 * @file: file pointer
945 *
946 * This function removes the file formerly added to the card via
947 * snd_card_file_add() function.
948 * If all files are removed and snd_card_free_when_closed() was
949 * called beforehand, it processes the pending release of
950 * resources.
951 *
952 * Return: Zero or a negative error code.
953 */
954int snd_card_file_remove(struct snd_card *card, struct file *file)
955{
956 struct snd_monitor_file *mfile, *found = NULL;
957
958 spin_lock(&card->files_lock);
959 list_for_each_entry(mfile, &card->files_list, list) {
960 if (mfile->file == file) {
961 list_del(&mfile->list);
962 spin_lock(&shutdown_lock);
963 list_del(&mfile->shutdown_list);
964 spin_unlock(&shutdown_lock);
965 if (mfile->disconnected_f_op)
966 fops_put(mfile->disconnected_f_op);
967 found = mfile;
968 break;
969 }
970 }
971 if (list_empty(&card->files_list))
972 wake_up_all(&card->remove_sleep);
973 spin_unlock(&card->files_lock);
974 if (!found) {
975 dev_err(card->dev, "card file remove problem (%p)\n", file);
976 return -ENOENT;
977 }
978 kfree(found);
979 put_device(&card->card_dev);
980 return 0;
981}
982EXPORT_SYMBOL(snd_card_file_remove);
983
984#ifdef CONFIG_PM
985/**
986 * snd_power_wait - wait until the power-state is changed.
987 * @card: soundcard structure
988 * @power_state: expected power state
989 *
990 * Waits until the power-state is changed.
991 *
992 * Return: Zero if successful, or a negative error code.
993 */
994int snd_power_wait(struct snd_card *card, unsigned int power_state)
995{
996 wait_queue_entry_t wait;
997 int result = 0;
998
999 /* fastpath */
1000 if (snd_power_get_state(card) == power_state)
1001 return 0;
1002 init_waitqueue_entry(&wait, current);
1003 add_wait_queue(&card->power_sleep, &wait);
1004 while (1) {
1005 if (card->shutdown) {
1006 result = -ENODEV;
1007 break;
1008 }
1009 if (snd_power_get_state(card) == power_state)
1010 break;
1011 set_current_state(TASK_UNINTERRUPTIBLE);
1012 schedule_timeout(30 * HZ);
1013 }
1014 remove_wait_queue(&card->power_sleep, &wait);
1015 return result;
1016}
1017EXPORT_SYMBOL(snd_power_wait);
1018#endif /* CONFIG_PM */
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/* monitor files for graceful shutdown (hotplug) */
35struct snd_monitor_file {
36 struct file *file;
37 const struct file_operations *disconnected_f_op;
38 struct list_head shutdown_list; /* still need to shutdown */
39 struct list_head list; /* link of monitor files */
40};
41
42static DEFINE_SPINLOCK(shutdown_lock);
43static LIST_HEAD(shutdown_files);
44
45static const struct file_operations snd_shutdown_f_ops;
46
47static unsigned int snd_cards_lock; /* locked for registering/using */
48struct snd_card *snd_cards[SNDRV_CARDS];
49EXPORT_SYMBOL(snd_cards);
50
51static DEFINE_MUTEX(snd_card_mutex);
52
53static char *slots[SNDRV_CARDS];
54module_param_array(slots, charp, NULL, 0444);
55MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
56
57/* return non-zero if the given index is reserved for the given
58 * module via slots option
59 */
60static int module_slot_match(struct module *module, int idx)
61{
62 int match = 1;
63#ifdef MODULE
64 const char *s1, *s2;
65
66 if (!module || !module->name || !slots[idx])
67 return 0;
68
69 s1 = module->name;
70 s2 = slots[idx];
71 if (*s2 == '!') {
72 match = 0; /* negative match */
73 s2++;
74 }
75 /* compare module name strings
76 * hyphens are handled as equivalent with underscore
77 */
78 for (;;) {
79 char c1 = *s1++;
80 char c2 = *s2++;
81 if (c1 == '-')
82 c1 = '_';
83 if (c2 == '-')
84 c2 = '_';
85 if (c1 != c2)
86 return !match;
87 if (!c1)
88 break;
89 }
90#endif /* MODULE */
91 return match;
92}
93
94#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
95int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
96EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
97#endif
98
99#ifdef CONFIG_PROC_FS
100static void snd_card_id_read(struct snd_info_entry *entry,
101 struct snd_info_buffer *buffer)
102{
103 snd_iprintf(buffer, "%s\n", entry->card->id);
104}
105
106static inline int init_info_for_card(struct snd_card *card)
107{
108 int err;
109 struct snd_info_entry *entry;
110
111 if ((err = snd_info_card_register(card)) < 0) {
112 snd_printd("unable to create card info\n");
113 return err;
114 }
115 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
116 snd_printd("unable to create card entry\n");
117 return err;
118 }
119 entry->c.text.read = snd_card_id_read;
120 if (snd_info_register(entry) < 0) {
121 snd_info_free_entry(entry);
122 entry = NULL;
123 }
124 card->proc_id = entry;
125 return 0;
126}
127#else /* !CONFIG_PROC_FS */
128#define init_info_for_card(card)
129#endif
130
131/**
132 * snd_card_create - create and initialize a soundcard structure
133 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
134 * @xid: card identification (ASCII string)
135 * @module: top level module for locking
136 * @extra_size: allocate this extra size after the main soundcard structure
137 * @card_ret: the pointer to store the created card instance
138 *
139 * Creates and initializes a soundcard structure.
140 *
141 * The function allocates snd_card instance via kzalloc with the given
142 * space for the driver to use freely. The allocated struct is stored
143 * in the given card_ret pointer.
144 *
145 * Returns zero if successful or a negative error code.
146 */
147int snd_card_create(int idx, const char *xid,
148 struct module *module, int extra_size,
149 struct snd_card **card_ret)
150{
151 struct snd_card *card;
152 int err, idx2;
153
154 if (snd_BUG_ON(!card_ret))
155 return -EINVAL;
156 *card_ret = NULL;
157
158 if (extra_size < 0)
159 extra_size = 0;
160 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
161 if (!card)
162 return -ENOMEM;
163 if (xid)
164 strlcpy(card->id, xid, sizeof(card->id));
165 err = 0;
166 mutex_lock(&snd_card_mutex);
167 if (idx < 0) {
168 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
169 /* idx == -1 == 0xffff means: take any free slot */
170 if (~snd_cards_lock & idx & 1<<idx2) {
171 if (module_slot_match(module, idx2)) {
172 idx = idx2;
173 break;
174 }
175 }
176 }
177 if (idx < 0) {
178 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
179 /* idx == -1 == 0xffff means: take any free slot */
180 if (~snd_cards_lock & idx & 1<<idx2) {
181 if (!slots[idx2] || !*slots[idx2]) {
182 idx = idx2;
183 break;
184 }
185 }
186 }
187 if (idx < 0)
188 err = -ENODEV;
189 else if (idx < snd_ecards_limit) {
190 if (snd_cards_lock & (1 << idx))
191 err = -EBUSY; /* invalid */
192 } else if (idx >= SNDRV_CARDS)
193 err = -ENODEV;
194 if (err < 0) {
195 mutex_unlock(&snd_card_mutex);
196 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
197 idx, snd_ecards_limit - 1, err);
198 goto __error;
199 }
200 snd_cards_lock |= 1 << idx; /* lock it */
201 if (idx >= snd_ecards_limit)
202 snd_ecards_limit = idx + 1; /* increase the limit */
203 mutex_unlock(&snd_card_mutex);
204 card->number = idx;
205 card->module = module;
206 INIT_LIST_HEAD(&card->devices);
207 init_rwsem(&card->controls_rwsem);
208 rwlock_init(&card->ctl_files_rwlock);
209 INIT_LIST_HEAD(&card->controls);
210 INIT_LIST_HEAD(&card->ctl_files);
211 spin_lock_init(&card->files_lock);
212 INIT_LIST_HEAD(&card->files_list);
213 init_waitqueue_head(&card->shutdown_sleep);
214#ifdef CONFIG_PM
215 mutex_init(&card->power_lock);
216 init_waitqueue_head(&card->power_sleep);
217#endif
218 /* the control interface cannot be accessed from the user space until */
219 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
220 err = snd_ctl_create(card);
221 if (err < 0) {
222 snd_printk(KERN_ERR "unable to register control minors\n");
223 goto __error;
224 }
225 err = snd_info_card_create(card);
226 if (err < 0) {
227 snd_printk(KERN_ERR "unable to create card info\n");
228 goto __error_ctl;
229 }
230 if (extra_size > 0)
231 card->private_data = (char *)card + sizeof(struct snd_card);
232 *card_ret = card;
233 return 0;
234
235 __error_ctl:
236 snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
237 __error:
238 kfree(card);
239 return err;
240}
241EXPORT_SYMBOL(snd_card_create);
242
243/* return non-zero if a card is already locked */
244int snd_card_locked(int card)
245{
246 int locked;
247
248 mutex_lock(&snd_card_mutex);
249 locked = snd_cards_lock & (1 << card);
250 mutex_unlock(&snd_card_mutex);
251 return locked;
252}
253
254static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
255{
256 return -ENODEV;
257}
258
259static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
260 size_t count, loff_t *offset)
261{
262 return -ENODEV;
263}
264
265static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
266 size_t count, loff_t *offset)
267{
268 return -ENODEV;
269}
270
271static int snd_disconnect_release(struct inode *inode, struct file *file)
272{
273 struct snd_monitor_file *df = NULL, *_df;
274
275 spin_lock(&shutdown_lock);
276 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
277 if (_df->file == file) {
278 df = _df;
279 list_del_init(&df->shutdown_list);
280 break;
281 }
282 }
283 spin_unlock(&shutdown_lock);
284
285 if (likely(df)) {
286 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
287 df->disconnected_f_op->fasync(-1, file, 0);
288 return df->disconnected_f_op->release(inode, file);
289 }
290
291 panic("%s(%p, %p) failed!", __func__, inode, file);
292}
293
294static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
295{
296 return POLLERR | POLLNVAL;
297}
298
299static long snd_disconnect_ioctl(struct file *file,
300 unsigned int cmd, unsigned long arg)
301{
302 return -ENODEV;
303}
304
305static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
306{
307 return -ENODEV;
308}
309
310static int snd_disconnect_fasync(int fd, struct file *file, int on)
311{
312 return -ENODEV;
313}
314
315static const struct file_operations snd_shutdown_f_ops =
316{
317 .owner = THIS_MODULE,
318 .llseek = snd_disconnect_llseek,
319 .read = snd_disconnect_read,
320 .write = snd_disconnect_write,
321 .release = snd_disconnect_release,
322 .poll = snd_disconnect_poll,
323 .unlocked_ioctl = snd_disconnect_ioctl,
324#ifdef CONFIG_COMPAT
325 .compat_ioctl = snd_disconnect_ioctl,
326#endif
327 .mmap = snd_disconnect_mmap,
328 .fasync = snd_disconnect_fasync
329};
330
331/**
332 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
333 * @card: soundcard structure
334 *
335 * Disconnects all APIs from the file-operations (user space).
336 *
337 * Returns zero, otherwise a negative error code.
338 *
339 * Note: The current implementation replaces all active file->f_op with special
340 * dummy file operations (they do nothing except release).
341 */
342int snd_card_disconnect(struct snd_card *card)
343{
344 struct snd_monitor_file *mfile;
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 /* it's critical part, use endless loop */
369 /* we have no room to fail */
370 mfile->disconnected_f_op = mfile->file->f_op;
371
372 spin_lock(&shutdown_lock);
373 list_add(&mfile->shutdown_list, &shutdown_files);
374 spin_unlock(&shutdown_lock);
375
376 mfile->file->f_op = &snd_shutdown_f_ops;
377 fops_get(mfile->file->f_op);
378 }
379 spin_unlock(&card->files_lock);
380
381 /* phase 3: notify all connected devices about disconnection */
382 /* at this point, they cannot respond to any calls except release() */
383
384#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
385 if (snd_mixer_oss_notify_callback)
386 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
387#endif
388
389 /* notify all devices that we are disconnected */
390 err = snd_device_disconnect_all(card);
391 if (err < 0)
392 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
393
394 snd_info_card_disconnect(card);
395 if (card->card_dev) {
396 device_unregister(card->card_dev);
397 card->card_dev = NULL;
398 }
399#ifdef CONFIG_PM
400 wake_up(&card->power_sleep);
401#endif
402 return 0;
403}
404
405EXPORT_SYMBOL(snd_card_disconnect);
406
407/**
408 * snd_card_free - frees given soundcard structure
409 * @card: soundcard structure
410 *
411 * This function releases the soundcard structure and the all assigned
412 * devices automatically. That is, you don't have to release the devices
413 * by yourself.
414 *
415 * Returns zero. Frees all associated devices and frees the control
416 * interface associated to given soundcard.
417 */
418static int snd_card_do_free(struct snd_card *card)
419{
420#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
421 if (snd_mixer_oss_notify_callback)
422 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
423#endif
424 if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
425 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
426 /* Fatal, but this situation should never occur */
427 }
428 if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
429 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
430 /* Fatal, but this situation should never occur */
431 }
432 if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
433 snd_printk(KERN_ERR "unable to free all devices (post)\n");
434 /* Fatal, but this situation should never occur */
435 }
436 if (card->private_free)
437 card->private_free(card);
438 snd_info_free_entry(card->proc_id);
439 if (snd_info_card_free(card) < 0) {
440 snd_printk(KERN_WARNING "unable to free card info\n");
441 /* Not fatal error */
442 }
443 kfree(card);
444 return 0;
445}
446
447int snd_card_free_when_closed(struct snd_card *card)
448{
449 int free_now = 0;
450 int ret = snd_card_disconnect(card);
451 if (ret)
452 return ret;
453
454 spin_lock(&card->files_lock);
455 if (list_empty(&card->files_list))
456 free_now = 1;
457 else
458 card->free_on_last_close = 1;
459 spin_unlock(&card->files_lock);
460
461 if (free_now)
462 snd_card_do_free(card);
463 return 0;
464}
465
466EXPORT_SYMBOL(snd_card_free_when_closed);
467
468int snd_card_free(struct snd_card *card)
469{
470 int ret = snd_card_disconnect(card);
471 if (ret)
472 return ret;
473
474 /* wait, until all devices are ready for the free operation */
475 wait_event(card->shutdown_sleep, list_empty(&card->files_list));
476 snd_card_do_free(card);
477 return 0;
478}
479
480EXPORT_SYMBOL(snd_card_free);
481
482static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
483{
484 int i, len, idx_flag = 0, loops = SNDRV_CARDS;
485 const char *spos, *src;
486 char *id;
487
488 if (nid == NULL) {
489 id = card->shortname;
490 spos = src = id;
491 while (*id != '\0') {
492 if (*id == ' ')
493 spos = id + 1;
494 id++;
495 }
496 } else {
497 spos = src = nid;
498 }
499 id = card->id;
500 while (*spos != '\0' && !isalnum(*spos))
501 spos++;
502 if (isdigit(*spos))
503 *id++ = isalpha(src[0]) ? src[0] : 'D';
504 while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
505 if (isalnum(*spos))
506 *id++ = *spos;
507 spos++;
508 }
509 *id = '\0';
510
511 id = card->id;
512
513 if (*id == '\0')
514 strcpy(id, "Default");
515
516 while (1) {
517 if (loops-- == 0) {
518 snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
519 strcpy(card->id, card->proc_root->name);
520 return;
521 }
522 if (!snd_info_check_reserved_words(id))
523 goto __change;
524 for (i = 0; i < snd_ecards_limit; i++) {
525 if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
526 goto __change;
527 }
528 break;
529
530 __change:
531 len = strlen(id);
532 if (idx_flag) {
533 if (id[len-1] != '9')
534 id[len-1]++;
535 else
536 id[len-1] = 'A';
537 } else if ((size_t)len <= sizeof(card->id) - 3) {
538 strcat(id, "_1");
539 idx_flag++;
540 } else {
541 spos = id + len - 2;
542 if ((size_t)len <= sizeof(card->id) - 2)
543 spos++;
544 *(char *)spos++ = '_';
545 *(char *)spos++ = '1';
546 *(char *)spos++ = '\0';
547 idx_flag++;
548 }
549 }
550}
551
552/**
553 * snd_card_set_id - set card identification name
554 * @card: soundcard structure
555 * @nid: new identification string
556 *
557 * This function sets the card identification and checks for name
558 * collisions.
559 */
560void snd_card_set_id(struct snd_card *card, const char *nid)
561{
562 /* check if user specified own card->id */
563 if (card->id[0] != '\0')
564 return;
565 mutex_lock(&snd_card_mutex);
566 snd_card_set_id_no_lock(card, nid);
567 mutex_unlock(&snd_card_mutex);
568}
569EXPORT_SYMBOL(snd_card_set_id);
570
571static ssize_t
572card_id_show_attr(struct device *dev,
573 struct device_attribute *attr, char *buf)
574{
575 struct snd_card *card = dev_get_drvdata(dev);
576 return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
577}
578
579static ssize_t
580card_id_store_attr(struct device *dev, struct device_attribute *attr,
581 const char *buf, size_t count)
582{
583 struct snd_card *card = dev_get_drvdata(dev);
584 char buf1[sizeof(card->id)];
585 size_t copy = count > sizeof(card->id) - 1 ?
586 sizeof(card->id) - 1 : count;
587 size_t idx;
588 int c;
589
590 for (idx = 0; idx < copy; idx++) {
591 c = buf[idx];
592 if (!isalnum(c) && c != '_' && c != '-')
593 return -EINVAL;
594 }
595 memcpy(buf1, buf, copy);
596 buf1[copy] = '\0';
597 mutex_lock(&snd_card_mutex);
598 if (!snd_info_check_reserved_words(buf1)) {
599 __exist:
600 mutex_unlock(&snd_card_mutex);
601 return -EEXIST;
602 }
603 for (idx = 0; idx < snd_ecards_limit; idx++) {
604 if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
605 if (card == snd_cards[idx])
606 goto __ok;
607 else
608 goto __exist;
609 }
610 }
611 strcpy(card->id, buf1);
612 snd_info_card_id_change(card);
613__ok:
614 mutex_unlock(&snd_card_mutex);
615
616 return count;
617}
618
619static struct device_attribute card_id_attrs =
620 __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
621
622static ssize_t
623card_number_show_attr(struct device *dev,
624 struct device_attribute *attr, char *buf)
625{
626 struct snd_card *card = dev_get_drvdata(dev);
627 return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
628}
629
630static struct device_attribute card_number_attrs =
631 __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
632
633/**
634 * snd_card_register - register the soundcard
635 * @card: soundcard structure
636 *
637 * This function registers all the devices assigned to the soundcard.
638 * Until calling this, the ALSA control interface is blocked from the
639 * external accesses. Thus, you should call this function at the end
640 * of the initialization of the card.
641 *
642 * Returns zero otherwise a negative error code if the registration failed.
643 */
644int snd_card_register(struct snd_card *card)
645{
646 int err;
647
648 if (snd_BUG_ON(!card))
649 return -EINVAL;
650
651 if (!card->card_dev) {
652 card->card_dev = device_create(sound_class, card->dev,
653 MKDEV(0, 0), card,
654 "card%i", card->number);
655 if (IS_ERR(card->card_dev))
656 card->card_dev = NULL;
657 }
658
659 if ((err = snd_device_register_all(card)) < 0)
660 return err;
661 mutex_lock(&snd_card_mutex);
662 if (snd_cards[card->number]) {
663 /* already registered */
664 mutex_unlock(&snd_card_mutex);
665 return 0;
666 }
667 snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
668 snd_cards[card->number] = card;
669 mutex_unlock(&snd_card_mutex);
670 init_info_for_card(card);
671#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
672 if (snd_mixer_oss_notify_callback)
673 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
674#endif
675 if (card->card_dev) {
676 err = device_create_file(card->card_dev, &card_id_attrs);
677 if (err < 0)
678 return err;
679 err = device_create_file(card->card_dev, &card_number_attrs);
680 if (err < 0)
681 return err;
682 }
683
684 return 0;
685}
686
687EXPORT_SYMBOL(snd_card_register);
688
689#ifdef CONFIG_PROC_FS
690static struct snd_info_entry *snd_card_info_entry;
691
692static void snd_card_info_read(struct snd_info_entry *entry,
693 struct snd_info_buffer *buffer)
694{
695 int idx, count;
696 struct snd_card *card;
697
698 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
699 mutex_lock(&snd_card_mutex);
700 if ((card = snd_cards[idx]) != NULL) {
701 count++;
702 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
703 idx,
704 card->id,
705 card->driver,
706 card->shortname);
707 snd_iprintf(buffer, " %s\n",
708 card->longname);
709 }
710 mutex_unlock(&snd_card_mutex);
711 }
712 if (!count)
713 snd_iprintf(buffer, "--- no soundcards ---\n");
714}
715
716#ifdef CONFIG_SND_OSSEMUL
717
718void snd_card_info_read_oss(struct snd_info_buffer *buffer)
719{
720 int idx, count;
721 struct snd_card *card;
722
723 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
724 mutex_lock(&snd_card_mutex);
725 if ((card = snd_cards[idx]) != NULL) {
726 count++;
727 snd_iprintf(buffer, "%s\n", card->longname);
728 }
729 mutex_unlock(&snd_card_mutex);
730 }
731 if (!count) {
732 snd_iprintf(buffer, "--- no soundcards ---\n");
733 }
734}
735
736#endif
737
738#ifdef MODULE
739static struct snd_info_entry *snd_card_module_info_entry;
740static void snd_card_module_info_read(struct snd_info_entry *entry,
741 struct snd_info_buffer *buffer)
742{
743 int idx;
744 struct snd_card *card;
745
746 for (idx = 0; idx < SNDRV_CARDS; idx++) {
747 mutex_lock(&snd_card_mutex);
748 if ((card = snd_cards[idx]) != NULL)
749 snd_iprintf(buffer, "%2i %s\n",
750 idx, card->module->name);
751 mutex_unlock(&snd_card_mutex);
752 }
753}
754#endif
755
756int __init snd_card_info_init(void)
757{
758 struct snd_info_entry *entry;
759
760 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
761 if (! entry)
762 return -ENOMEM;
763 entry->c.text.read = snd_card_info_read;
764 if (snd_info_register(entry) < 0) {
765 snd_info_free_entry(entry);
766 return -ENOMEM;
767 }
768 snd_card_info_entry = entry;
769
770#ifdef MODULE
771 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
772 if (entry) {
773 entry->c.text.read = snd_card_module_info_read;
774 if (snd_info_register(entry) < 0)
775 snd_info_free_entry(entry);
776 else
777 snd_card_module_info_entry = entry;
778 }
779#endif
780
781 return 0;
782}
783
784int __exit snd_card_info_done(void)
785{
786 snd_info_free_entry(snd_card_info_entry);
787#ifdef MODULE
788 snd_info_free_entry(snd_card_module_info_entry);
789#endif
790 return 0;
791}
792
793#endif /* CONFIG_PROC_FS */
794
795/**
796 * snd_component_add - add a component string
797 * @card: soundcard structure
798 * @component: the component id string
799 *
800 * This function adds the component id string to the supported list.
801 * The component can be referred from the alsa-lib.
802 *
803 * Returns zero otherwise a negative error code.
804 */
805
806int snd_component_add(struct snd_card *card, const char *component)
807{
808 char *ptr;
809 int len = strlen(component);
810
811 ptr = strstr(card->components, component);
812 if (ptr != NULL) {
813 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
814 return 1;
815 }
816 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
817 snd_BUG();
818 return -ENOMEM;
819 }
820 if (card->components[0] != '\0')
821 strcat(card->components, " ");
822 strcat(card->components, component);
823 return 0;
824}
825
826EXPORT_SYMBOL(snd_component_add);
827
828/**
829 * snd_card_file_add - add the file to the file list of the card
830 * @card: soundcard structure
831 * @file: file pointer
832 *
833 * This function adds the file to the file linked-list of the card.
834 * This linked-list is used to keep tracking the connection state,
835 * and to avoid the release of busy resources by hotplug.
836 *
837 * Returns zero or a negative error code.
838 */
839int snd_card_file_add(struct snd_card *card, struct file *file)
840{
841 struct snd_monitor_file *mfile;
842
843 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
844 if (mfile == NULL)
845 return -ENOMEM;
846 mfile->file = file;
847 mfile->disconnected_f_op = NULL;
848 INIT_LIST_HEAD(&mfile->shutdown_list);
849 spin_lock(&card->files_lock);
850 if (card->shutdown) {
851 spin_unlock(&card->files_lock);
852 kfree(mfile);
853 return -ENODEV;
854 }
855 list_add(&mfile->list, &card->files_list);
856 spin_unlock(&card->files_lock);
857 return 0;
858}
859
860EXPORT_SYMBOL(snd_card_file_add);
861
862/**
863 * snd_card_file_remove - remove the file from the file list
864 * @card: soundcard structure
865 * @file: file pointer
866 *
867 * This function removes the file formerly added to the card via
868 * snd_card_file_add() function.
869 * If all files are removed and snd_card_free_when_closed() was
870 * called beforehand, it processes the pending release of
871 * resources.
872 *
873 * Returns zero or a negative error code.
874 */
875int snd_card_file_remove(struct snd_card *card, struct file *file)
876{
877 struct snd_monitor_file *mfile, *found = NULL;
878 int last_close = 0;
879
880 spin_lock(&card->files_lock);
881 list_for_each_entry(mfile, &card->files_list, list) {
882 if (mfile->file == file) {
883 list_del(&mfile->list);
884 spin_lock(&shutdown_lock);
885 list_del(&mfile->shutdown_list);
886 spin_unlock(&shutdown_lock);
887 if (mfile->disconnected_f_op)
888 fops_put(mfile->disconnected_f_op);
889 found = mfile;
890 break;
891 }
892 }
893 if (list_empty(&card->files_list))
894 last_close = 1;
895 spin_unlock(&card->files_lock);
896 if (last_close) {
897 wake_up(&card->shutdown_sleep);
898 if (card->free_on_last_close)
899 snd_card_do_free(card);
900 }
901 if (!found) {
902 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
903 return -ENOENT;
904 }
905 kfree(found);
906 return 0;
907}
908
909EXPORT_SYMBOL(snd_card_file_remove);
910
911#ifdef CONFIG_PM
912/**
913 * snd_power_wait - wait until the power-state is changed.
914 * @card: soundcard structure
915 * @power_state: expected power state
916 *
917 * Waits until the power-state is changed.
918 *
919 * Note: the power lock must be active before call.
920 */
921int snd_power_wait(struct snd_card *card, unsigned int power_state)
922{
923 wait_queue_t wait;
924 int result = 0;
925
926 /* fastpath */
927 if (snd_power_get_state(card) == power_state)
928 return 0;
929 init_waitqueue_entry(&wait, current);
930 add_wait_queue(&card->power_sleep, &wait);
931 while (1) {
932 if (card->shutdown) {
933 result = -ENODEV;
934 break;
935 }
936 if (snd_power_get_state(card) == power_state)
937 break;
938 set_current_state(TASK_UNINTERRUPTIBLE);
939 snd_power_unlock(card);
940 schedule_timeout(30 * HZ);
941 snd_power_lock(card);
942 }
943 remove_wait_queue(&card->power_sleep, &wait);
944 return result;
945}
946
947EXPORT_SYMBOL(snd_power_wait);
948#endif /* CONFIG_PM */