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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 */
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/debugfs.h>
17#include <linux/completion.h>
18#include <linux/interrupt.h>
19
20#include <sound/core.h>
21#include <sound/control.h>
22#include <sound/info.h>
23
24/* monitor files for graceful shutdown (hotplug) */
25struct snd_monitor_file {
26 struct file *file;
27 const struct file_operations *disconnected_f_op;
28 struct list_head shutdown_list; /* still need to shutdown */
29 struct list_head list; /* link of monitor files */
30};
31
32static DEFINE_SPINLOCK(shutdown_lock);
33static LIST_HEAD(shutdown_files);
34
35static const struct file_operations snd_shutdown_f_ops;
36
37/* locked for registering/using */
38static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
39static struct snd_card *snd_cards[SNDRV_CARDS];
40
41static DEFINE_MUTEX(snd_card_mutex);
42
43static char *slots[SNDRV_CARDS];
44module_param_array(slots, charp, NULL, 0444);
45MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
46
47/* return non-zero if the given index is reserved for the given
48 * module via slots option
49 */
50static int module_slot_match(struct module *module, int idx)
51{
52 int match = 1;
53#ifdef MODULE
54 const char *s1, *s2;
55
56 if (!module || !*module->name || !slots[idx])
57 return 0;
58
59 s1 = module->name;
60 s2 = slots[idx];
61 if (*s2 == '!') {
62 match = 0; /* negative match */
63 s2++;
64 }
65 /* compare module name strings
66 * hyphens are handled as equivalent with underscore
67 */
68 for (;;) {
69 char c1 = *s1++;
70 char c2 = *s2++;
71 if (c1 == '-')
72 c1 = '_';
73 if (c2 == '-')
74 c2 = '_';
75 if (c1 != c2)
76 return !match;
77 if (!c1)
78 break;
79 }
80#endif /* MODULE */
81 return match;
82}
83
84#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
85int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
86EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
87#endif
88
89static int check_empty_slot(struct module *module, int slot)
90{
91 return !slots[slot] || !*slots[slot];
92}
93
94/* return an empty slot number (>= 0) found in the given bitmask @mask.
95 * @mask == -1 == 0xffffffff means: take any free slot up to 32
96 * when no slot is available, return the original @mask as is.
97 */
98static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
99 struct module *module)
100{
101 int slot;
102
103 for (slot = 0; slot < SNDRV_CARDS; slot++) {
104 if (slot < 32 && !(mask & (1U << slot)))
105 continue;
106 if (!test_bit(slot, snd_cards_lock)) {
107 if (check(module, slot))
108 return slot; /* found */
109 }
110 }
111 return mask; /* unchanged */
112}
113
114/* the default release callback set in snd_device_alloc() */
115static void default_release_alloc(struct device *dev)
116{
117 kfree(dev);
118}
119
120/**
121 * snd_device_alloc - Allocate and initialize struct device for sound devices
122 * @dev_p: pointer to store the allocated device
123 * @card: card to assign, optional
124 *
125 * For releasing the allocated device, call put_device().
126 */
127int snd_device_alloc(struct device **dev_p, struct snd_card *card)
128{
129 struct device *dev;
130
131 *dev_p = NULL;
132 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
133 if (!dev)
134 return -ENOMEM;
135 device_initialize(dev);
136 if (card)
137 dev->parent = &card->card_dev;
138 dev->class = &sound_class;
139 dev->release = default_release_alloc;
140 *dev_p = dev;
141 return 0;
142}
143EXPORT_SYMBOL_GPL(snd_device_alloc);
144
145static int snd_card_init(struct snd_card *card, struct device *parent,
146 int idx, const char *xid, struct module *module,
147 size_t extra_size);
148static int snd_card_do_free(struct snd_card *card);
149static const struct attribute_group card_dev_attr_group;
150
151static void release_card_device(struct device *dev)
152{
153 snd_card_do_free(dev_to_snd_card(dev));
154}
155
156/**
157 * snd_card_new - create and initialize a soundcard structure
158 * @parent: the parent device object
159 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
160 * @xid: card identification (ASCII string)
161 * @module: top level module for locking
162 * @extra_size: allocate this extra size after the main soundcard structure
163 * @card_ret: the pointer to store the created card instance
164 *
165 * The function allocates snd_card instance via kzalloc with the given
166 * space for the driver to use freely. The allocated struct is stored
167 * in the given card_ret pointer.
168 *
169 * Return: Zero if successful or a negative error code.
170 */
171int snd_card_new(struct device *parent, int idx, const char *xid,
172 struct module *module, int extra_size,
173 struct snd_card **card_ret)
174{
175 struct snd_card *card;
176 int err;
177
178 if (snd_BUG_ON(!card_ret))
179 return -EINVAL;
180 *card_ret = NULL;
181
182 if (extra_size < 0)
183 extra_size = 0;
184 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
185 if (!card)
186 return -ENOMEM;
187
188 err = snd_card_init(card, parent, idx, xid, module, extra_size);
189 if (err < 0)
190 return err; /* card is freed by error handler */
191
192 *card_ret = card;
193 return 0;
194}
195EXPORT_SYMBOL(snd_card_new);
196
197static void __snd_card_release(struct device *dev, void *data)
198{
199 snd_card_free(data);
200}
201
202/**
203 * snd_devm_card_new - managed snd_card object creation
204 * @parent: the parent device object
205 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
206 * @xid: card identification (ASCII string)
207 * @module: top level module for locking
208 * @extra_size: allocate this extra size after the main soundcard structure
209 * @card_ret: the pointer to store the created card instance
210 *
211 * This function works like snd_card_new() but manages the allocated resource
212 * via devres, i.e. you don't need to free explicitly.
213 *
214 * When a snd_card object is created with this function and registered via
215 * snd_card_register(), the very first devres action to call snd_card_free()
216 * is added automatically. In that way, the resource disconnection is assured
217 * at first, then released in the expected order.
218 *
219 * If an error happens at the probe before snd_card_register() is called and
220 * there have been other devres resources, you'd need to free the card manually
221 * via snd_card_free() call in the error; otherwise it may lead to UAF due to
222 * devres call orders. You can use snd_card_free_on_error() helper for
223 * handling it more easily.
224 *
225 * Return: zero if successful, or a negative error code
226 */
227int snd_devm_card_new(struct device *parent, int idx, const char *xid,
228 struct module *module, size_t extra_size,
229 struct snd_card **card_ret)
230{
231 struct snd_card *card;
232 int err;
233
234 *card_ret = NULL;
235 card = devres_alloc(__snd_card_release, sizeof(*card) + extra_size,
236 GFP_KERNEL);
237 if (!card)
238 return -ENOMEM;
239 card->managed = true;
240 err = snd_card_init(card, parent, idx, xid, module, extra_size);
241 if (err < 0) {
242 devres_free(card); /* in managed mode, we need to free manually */
243 return err;
244 }
245
246 devres_add(parent, card);
247 *card_ret = card;
248 return 0;
249}
250EXPORT_SYMBOL_GPL(snd_devm_card_new);
251
252/**
253 * snd_card_free_on_error - a small helper for handling devm probe errors
254 * @dev: the managed device object
255 * @ret: the return code from the probe callback
256 *
257 * This function handles the explicit snd_card_free() call at the error from
258 * the probe callback. It's just a small helper for simplifying the error
259 * handling with the managed devices.
260 *
261 * Return: zero if successful, or a negative error code
262 */
263int snd_card_free_on_error(struct device *dev, int ret)
264{
265 struct snd_card *card;
266
267 if (!ret)
268 return 0;
269 card = devres_find(dev, __snd_card_release, NULL, NULL);
270 if (card)
271 snd_card_free(card);
272 return ret;
273}
274EXPORT_SYMBOL_GPL(snd_card_free_on_error);
275
276static int snd_card_init(struct snd_card *card, struct device *parent,
277 int idx, const char *xid, struct module *module,
278 size_t extra_size)
279{
280 int err;
281
282 if (extra_size > 0)
283 card->private_data = (char *)card + sizeof(struct snd_card);
284 if (xid)
285 strscpy(card->id, xid, sizeof(card->id));
286 err = 0;
287 mutex_lock(&snd_card_mutex);
288 if (idx < 0) /* first check the matching module-name slot */
289 idx = get_slot_from_bitmask(idx, module_slot_match, module);
290 if (idx < 0) /* if not matched, assign an empty slot */
291 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
292 if (idx < 0)
293 err = -ENODEV;
294 else if (idx < snd_ecards_limit) {
295 if (test_bit(idx, snd_cards_lock))
296 err = -EBUSY; /* invalid */
297 } else if (idx >= SNDRV_CARDS)
298 err = -ENODEV;
299 if (err < 0) {
300 mutex_unlock(&snd_card_mutex);
301 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
302 idx, snd_ecards_limit - 1, err);
303 if (!card->managed)
304 kfree(card); /* manually free here, as no destructor called */
305 return err;
306 }
307 set_bit(idx, snd_cards_lock); /* lock it */
308 if (idx >= snd_ecards_limit)
309 snd_ecards_limit = idx + 1; /* increase the limit */
310 mutex_unlock(&snd_card_mutex);
311 card->dev = parent;
312 card->number = idx;
313#ifdef MODULE
314 WARN_ON(!module);
315 card->module = module;
316#endif
317 INIT_LIST_HEAD(&card->devices);
318 init_rwsem(&card->controls_rwsem);
319 rwlock_init(&card->ctl_files_rwlock);
320 INIT_LIST_HEAD(&card->controls);
321 INIT_LIST_HEAD(&card->ctl_files);
322#ifdef CONFIG_SND_CTL_FAST_LOOKUP
323 xa_init(&card->ctl_numids);
324 xa_init(&card->ctl_hash);
325#endif
326 spin_lock_init(&card->files_lock);
327 INIT_LIST_HEAD(&card->files_list);
328 mutex_init(&card->memory_mutex);
329#ifdef CONFIG_PM
330 init_waitqueue_head(&card->power_sleep);
331 init_waitqueue_head(&card->power_ref_sleep);
332 atomic_set(&card->power_ref, 0);
333#endif
334 init_waitqueue_head(&card->remove_sleep);
335 card->sync_irq = -1;
336
337 device_initialize(&card->card_dev);
338 card->card_dev.parent = parent;
339 card->card_dev.class = &sound_class;
340 card->card_dev.release = release_card_device;
341 card->card_dev.groups = card->dev_groups;
342 card->dev_groups[0] = &card_dev_attr_group;
343 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
344 if (err < 0)
345 goto __error;
346
347 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
348 dev_driver_string(card->dev), dev_name(&card->card_dev));
349
350 /* the control interface cannot be accessed from the user space until */
351 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
352 err = snd_ctl_create(card);
353 if (err < 0) {
354 dev_err(parent, "unable to register control minors\n");
355 goto __error;
356 }
357 err = snd_info_card_create(card);
358 if (err < 0) {
359 dev_err(parent, "unable to create card info\n");
360 goto __error_ctl;
361 }
362
363#ifdef CONFIG_SND_DEBUG
364 card->debugfs_root = debugfs_create_dir(dev_name(&card->card_dev),
365 sound_debugfs_root);
366#endif
367 return 0;
368
369 __error_ctl:
370 snd_device_free_all(card);
371 __error:
372 put_device(&card->card_dev);
373 return err;
374}
375
376/**
377 * snd_card_ref - Get the card object from the index
378 * @idx: the card index
379 *
380 * Returns a card object corresponding to the given index or NULL if not found.
381 * Release the object via snd_card_unref().
382 *
383 * Return: a card object or NULL
384 */
385struct snd_card *snd_card_ref(int idx)
386{
387 struct snd_card *card;
388
389 mutex_lock(&snd_card_mutex);
390 card = snd_cards[idx];
391 if (card)
392 get_device(&card->card_dev);
393 mutex_unlock(&snd_card_mutex);
394 return card;
395}
396EXPORT_SYMBOL_GPL(snd_card_ref);
397
398/* return non-zero if a card is already locked */
399int snd_card_locked(int card)
400{
401 int locked;
402
403 mutex_lock(&snd_card_mutex);
404 locked = test_bit(card, snd_cards_lock);
405 mutex_unlock(&snd_card_mutex);
406 return locked;
407}
408
409static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
410{
411 return -ENODEV;
412}
413
414static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
415 size_t count, loff_t *offset)
416{
417 return -ENODEV;
418}
419
420static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
421 size_t count, loff_t *offset)
422{
423 return -ENODEV;
424}
425
426static int snd_disconnect_release(struct inode *inode, struct file *file)
427{
428 struct snd_monitor_file *df = NULL, *_df;
429
430 spin_lock(&shutdown_lock);
431 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
432 if (_df->file == file) {
433 df = _df;
434 list_del_init(&df->shutdown_list);
435 break;
436 }
437 }
438 spin_unlock(&shutdown_lock);
439
440 if (likely(df)) {
441 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
442 df->disconnected_f_op->fasync(-1, file, 0);
443 return df->disconnected_f_op->release(inode, file);
444 }
445
446 panic("%s(%p, %p) failed!", __func__, inode, file);
447}
448
449static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
450{
451 return EPOLLERR | EPOLLNVAL;
452}
453
454static long snd_disconnect_ioctl(struct file *file,
455 unsigned int cmd, unsigned long arg)
456{
457 return -ENODEV;
458}
459
460static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
461{
462 return -ENODEV;
463}
464
465static int snd_disconnect_fasync(int fd, struct file *file, int on)
466{
467 return -ENODEV;
468}
469
470static const struct file_operations snd_shutdown_f_ops =
471{
472 .owner = THIS_MODULE,
473 .llseek = snd_disconnect_llseek,
474 .read = snd_disconnect_read,
475 .write = snd_disconnect_write,
476 .release = snd_disconnect_release,
477 .poll = snd_disconnect_poll,
478 .unlocked_ioctl = snd_disconnect_ioctl,
479#ifdef CONFIG_COMPAT
480 .compat_ioctl = snd_disconnect_ioctl,
481#endif
482 .mmap = snd_disconnect_mmap,
483 .fasync = snd_disconnect_fasync
484};
485
486/**
487 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
488 * @card: soundcard structure
489 *
490 * Disconnects all APIs from the file-operations (user space).
491 *
492 * Return: Zero, otherwise a negative error code.
493 *
494 * Note: The current implementation replaces all active file->f_op with special
495 * dummy file operations (they do nothing except release).
496 */
497void snd_card_disconnect(struct snd_card *card)
498{
499 struct snd_monitor_file *mfile;
500
501 if (!card)
502 return;
503
504 spin_lock(&card->files_lock);
505 if (card->shutdown) {
506 spin_unlock(&card->files_lock);
507 return;
508 }
509 card->shutdown = 1;
510
511 /* replace file->f_op with special dummy operations */
512 list_for_each_entry(mfile, &card->files_list, list) {
513 /* it's critical part, use endless loop */
514 /* we have no room to fail */
515 mfile->disconnected_f_op = mfile->file->f_op;
516
517 spin_lock(&shutdown_lock);
518 list_add(&mfile->shutdown_list, &shutdown_files);
519 spin_unlock(&shutdown_lock);
520
521 mfile->file->f_op = &snd_shutdown_f_ops;
522 fops_get(mfile->file->f_op);
523 }
524 spin_unlock(&card->files_lock);
525
526 /* notify all connected devices about disconnection */
527 /* at this point, they cannot respond to any calls except release() */
528
529#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
530 if (snd_mixer_oss_notify_callback)
531 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
532#endif
533
534 /* notify all devices that we are disconnected */
535 snd_device_disconnect_all(card);
536
537 if (card->sync_irq > 0)
538 synchronize_irq(card->sync_irq);
539
540 snd_info_card_disconnect(card);
541 if (card->registered) {
542 device_del(&card->card_dev);
543 card->registered = false;
544 }
545
546 /* disable fops (user space) operations for ALSA API */
547 mutex_lock(&snd_card_mutex);
548 snd_cards[card->number] = NULL;
549 clear_bit(card->number, snd_cards_lock);
550 mutex_unlock(&snd_card_mutex);
551
552#ifdef CONFIG_PM
553 wake_up(&card->power_sleep);
554 snd_power_sync_ref(card);
555#endif
556}
557EXPORT_SYMBOL(snd_card_disconnect);
558
559/**
560 * snd_card_disconnect_sync - disconnect card and wait until files get closed
561 * @card: card object to disconnect
562 *
563 * This calls snd_card_disconnect() for disconnecting all belonging components
564 * and waits until all pending files get closed.
565 * It assures that all accesses from user-space finished so that the driver
566 * can release its resources gracefully.
567 */
568void snd_card_disconnect_sync(struct snd_card *card)
569{
570 snd_card_disconnect(card);
571
572 spin_lock_irq(&card->files_lock);
573 wait_event_lock_irq(card->remove_sleep,
574 list_empty(&card->files_list),
575 card->files_lock);
576 spin_unlock_irq(&card->files_lock);
577}
578EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
579
580static int snd_card_do_free(struct snd_card *card)
581{
582 card->releasing = true;
583#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
584 if (snd_mixer_oss_notify_callback)
585 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
586#endif
587 snd_device_free_all(card);
588 if (card->private_free)
589 card->private_free(card);
590 if (snd_info_card_free(card) < 0) {
591 dev_warn(card->dev, "unable to free card info\n");
592 /* Not fatal error */
593 }
594#ifdef CONFIG_SND_DEBUG
595 debugfs_remove(card->debugfs_root);
596 card->debugfs_root = NULL;
597#endif
598 if (card->release_completion)
599 complete(card->release_completion);
600 if (!card->managed)
601 kfree(card);
602 return 0;
603}
604
605/**
606 * snd_card_free_when_closed - Disconnect the card, free it later eventually
607 * @card: soundcard structure
608 *
609 * Unlike snd_card_free(), this function doesn't try to release the card
610 * resource immediately, but tries to disconnect at first. When the card
611 * is still in use, the function returns before freeing the resources.
612 * The card resources will be freed when the refcount gets to zero.
613 *
614 * Return: zero if successful, or a negative error code
615 */
616void snd_card_free_when_closed(struct snd_card *card)
617{
618 if (!card)
619 return;
620
621 snd_card_disconnect(card);
622 put_device(&card->card_dev);
623 return;
624}
625EXPORT_SYMBOL(snd_card_free_when_closed);
626
627/**
628 * snd_card_free - frees given soundcard structure
629 * @card: soundcard structure
630 *
631 * This function releases the soundcard structure and the all assigned
632 * devices automatically. That is, you don't have to release the devices
633 * by yourself.
634 *
635 * This function waits until the all resources are properly released.
636 *
637 * Return: Zero. Frees all associated devices and frees the control
638 * interface associated to given soundcard.
639 */
640void snd_card_free(struct snd_card *card)
641{
642 DECLARE_COMPLETION_ONSTACK(released);
643
644 /* The call of snd_card_free() is allowed from various code paths;
645 * a manual call from the driver and the call via devres_free, and
646 * we need to avoid double-free. Moreover, the release via devres
647 * may call snd_card_free() twice due to its nature, we need to have
648 * the check here at the beginning.
649 */
650 if (card->releasing)
651 return;
652
653 card->release_completion = &released;
654 snd_card_free_when_closed(card);
655
656 /* wait, until all devices are ready for the free operation */
657 wait_for_completion(&released);
658}
659EXPORT_SYMBOL(snd_card_free);
660
661/* retrieve the last word of shortname or longname */
662static const char *retrieve_id_from_card_name(const char *name)
663{
664 const char *spos = name;
665
666 while (*name) {
667 if (isspace(*name) && isalnum(name[1]))
668 spos = name + 1;
669 name++;
670 }
671 return spos;
672}
673
674/* return true if the given id string doesn't conflict any other card ids */
675static bool card_id_ok(struct snd_card *card, const char *id)
676{
677 int i;
678 if (!snd_info_check_reserved_words(id))
679 return false;
680 for (i = 0; i < snd_ecards_limit; i++) {
681 if (snd_cards[i] && snd_cards[i] != card &&
682 !strcmp(snd_cards[i]->id, id))
683 return false;
684 }
685 return true;
686}
687
688/* copy to card->id only with valid letters from nid */
689static void copy_valid_id_string(struct snd_card *card, const char *src,
690 const char *nid)
691{
692 char *id = card->id;
693
694 while (*nid && !isalnum(*nid))
695 nid++;
696 if (isdigit(*nid))
697 *id++ = isalpha(*src) ? *src : 'D';
698 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
699 if (isalnum(*nid))
700 *id++ = *nid;
701 nid++;
702 }
703 *id = 0;
704}
705
706/* Set card->id from the given string
707 * If the string conflicts with other ids, add a suffix to make it unique.
708 */
709static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
710 const char *nid)
711{
712 int len, loops;
713 bool is_default = false;
714 char *id;
715
716 copy_valid_id_string(card, src, nid);
717 id = card->id;
718
719 again:
720 /* use "Default" for obviously invalid strings
721 * ("card" conflicts with proc directories)
722 */
723 if (!*id || !strncmp(id, "card", 4)) {
724 strcpy(id, "Default");
725 is_default = true;
726 }
727
728 len = strlen(id);
729 for (loops = 0; loops < SNDRV_CARDS; loops++) {
730 char *spos;
731 char sfxstr[5]; /* "_012" */
732 int sfxlen;
733
734 if (card_id_ok(card, id))
735 return; /* OK */
736
737 /* Add _XYZ suffix */
738 sprintf(sfxstr, "_%X", loops + 1);
739 sfxlen = strlen(sfxstr);
740 if (len + sfxlen >= sizeof(card->id))
741 spos = id + sizeof(card->id) - sfxlen - 1;
742 else
743 spos = id + len;
744 strcpy(spos, sfxstr);
745 }
746 /* fallback to the default id */
747 if (!is_default) {
748 *id = 0;
749 goto again;
750 }
751 /* last resort... */
752 dev_err(card->dev, "unable to set card id (%s)\n", id);
753 if (card->proc_root->name)
754 strscpy(card->id, card->proc_root->name, sizeof(card->id));
755}
756
757/**
758 * snd_card_set_id - set card identification name
759 * @card: soundcard structure
760 * @nid: new identification string
761 *
762 * This function sets the card identification and checks for name
763 * collisions.
764 */
765void snd_card_set_id(struct snd_card *card, const char *nid)
766{
767 /* check if user specified own card->id */
768 if (card->id[0] != '\0')
769 return;
770 mutex_lock(&snd_card_mutex);
771 snd_card_set_id_no_lock(card, nid, nid);
772 mutex_unlock(&snd_card_mutex);
773}
774EXPORT_SYMBOL(snd_card_set_id);
775
776static ssize_t id_show(struct device *dev,
777 struct device_attribute *attr, char *buf)
778{
779 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
780 return sysfs_emit(buf, "%s\n", card->id);
781}
782
783static ssize_t id_store(struct device *dev, struct device_attribute *attr,
784 const char *buf, size_t count)
785{
786 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
787 char buf1[sizeof(card->id)];
788 size_t copy = count > sizeof(card->id) - 1 ?
789 sizeof(card->id) - 1 : count;
790 size_t idx;
791 int c;
792
793 for (idx = 0; idx < copy; idx++) {
794 c = buf[idx];
795 if (!isalnum(c) && c != '_' && c != '-')
796 return -EINVAL;
797 }
798 memcpy(buf1, buf, copy);
799 buf1[copy] = '\0';
800 mutex_lock(&snd_card_mutex);
801 if (!card_id_ok(NULL, buf1)) {
802 mutex_unlock(&snd_card_mutex);
803 return -EEXIST;
804 }
805 strcpy(card->id, buf1);
806 snd_info_card_id_change(card);
807 mutex_unlock(&snd_card_mutex);
808
809 return count;
810}
811
812static DEVICE_ATTR_RW(id);
813
814static ssize_t number_show(struct device *dev,
815 struct device_attribute *attr, char *buf)
816{
817 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
818 return sysfs_emit(buf, "%i\n", card->number);
819}
820
821static DEVICE_ATTR_RO(number);
822
823static struct attribute *card_dev_attrs[] = {
824 &dev_attr_id.attr,
825 &dev_attr_number.attr,
826 NULL
827};
828
829static const struct attribute_group card_dev_attr_group = {
830 .attrs = card_dev_attrs,
831};
832
833/**
834 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
835 * @card: card instance
836 * @group: attribute group to append
837 *
838 * Return: zero if successful, or a negative error code
839 */
840int snd_card_add_dev_attr(struct snd_card *card,
841 const struct attribute_group *group)
842{
843 int i;
844
845 /* loop for (arraysize-1) here to keep NULL at the last entry */
846 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
847 if (!card->dev_groups[i]) {
848 card->dev_groups[i] = group;
849 return 0;
850 }
851 }
852
853 dev_err(card->dev, "Too many groups assigned\n");
854 return -ENOSPC;
855}
856EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
857
858static void trigger_card_free(void *data)
859{
860 snd_card_free(data);
861}
862
863/**
864 * snd_card_register - register the soundcard
865 * @card: soundcard structure
866 *
867 * This function registers all the devices assigned to the soundcard.
868 * Until calling this, the ALSA control interface is blocked from the
869 * external accesses. Thus, you should call this function at the end
870 * of the initialization of the card.
871 *
872 * Return: Zero otherwise a negative error code if the registration failed.
873 */
874int snd_card_register(struct snd_card *card)
875{
876 int err;
877
878 if (snd_BUG_ON(!card))
879 return -EINVAL;
880
881 if (!card->registered) {
882 err = device_add(&card->card_dev);
883 if (err < 0)
884 return err;
885 card->registered = true;
886 } else {
887 if (card->managed)
888 devm_remove_action(card->dev, trigger_card_free, card);
889 }
890
891 if (card->managed) {
892 err = devm_add_action(card->dev, trigger_card_free, card);
893 if (err < 0)
894 return err;
895 }
896
897 err = snd_device_register_all(card);
898 if (err < 0)
899 return err;
900 mutex_lock(&snd_card_mutex);
901 if (snd_cards[card->number]) {
902 /* already registered */
903 mutex_unlock(&snd_card_mutex);
904 return snd_info_card_register(card); /* register pending info */
905 }
906 if (*card->id) {
907 /* make a unique id name from the given string */
908 char tmpid[sizeof(card->id)];
909 memcpy(tmpid, card->id, sizeof(card->id));
910 snd_card_set_id_no_lock(card, tmpid, tmpid);
911 } else {
912 /* create an id from either shortname or longname */
913 const char *src;
914 src = *card->shortname ? card->shortname : card->longname;
915 snd_card_set_id_no_lock(card, src,
916 retrieve_id_from_card_name(src));
917 }
918 snd_cards[card->number] = card;
919 mutex_unlock(&snd_card_mutex);
920 err = snd_info_card_register(card);
921 if (err < 0)
922 return err;
923
924#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
925 if (snd_mixer_oss_notify_callback)
926 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
927#endif
928 return 0;
929}
930EXPORT_SYMBOL(snd_card_register);
931
932#ifdef CONFIG_SND_PROC_FS
933static void snd_card_info_read(struct snd_info_entry *entry,
934 struct snd_info_buffer *buffer)
935{
936 int idx, count;
937 struct snd_card *card;
938
939 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
940 mutex_lock(&snd_card_mutex);
941 card = snd_cards[idx];
942 if (card) {
943 count++;
944 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
945 idx,
946 card->id,
947 card->driver,
948 card->shortname);
949 snd_iprintf(buffer, " %s\n",
950 card->longname);
951 }
952 mutex_unlock(&snd_card_mutex);
953 }
954 if (!count)
955 snd_iprintf(buffer, "--- no soundcards ---\n");
956}
957
958#ifdef CONFIG_SND_OSSEMUL
959void snd_card_info_read_oss(struct snd_info_buffer *buffer)
960{
961 int idx, count;
962 struct snd_card *card;
963
964 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
965 mutex_lock(&snd_card_mutex);
966 card = snd_cards[idx];
967 if (card) {
968 count++;
969 snd_iprintf(buffer, "%s\n", card->longname);
970 }
971 mutex_unlock(&snd_card_mutex);
972 }
973 if (!count) {
974 snd_iprintf(buffer, "--- no soundcards ---\n");
975 }
976}
977
978#endif
979
980#ifdef MODULE
981static void snd_card_module_info_read(struct snd_info_entry *entry,
982 struct snd_info_buffer *buffer)
983{
984 int idx;
985 struct snd_card *card;
986
987 for (idx = 0; idx < SNDRV_CARDS; idx++) {
988 mutex_lock(&snd_card_mutex);
989 card = snd_cards[idx];
990 if (card)
991 snd_iprintf(buffer, "%2i %s\n",
992 idx, card->module->name);
993 mutex_unlock(&snd_card_mutex);
994 }
995}
996#endif
997
998int __init snd_card_info_init(void)
999{
1000 struct snd_info_entry *entry;
1001
1002 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
1003 if (! entry)
1004 return -ENOMEM;
1005 entry->c.text.read = snd_card_info_read;
1006 if (snd_info_register(entry) < 0)
1007 return -ENOMEM; /* freed in error path */
1008
1009#ifdef MODULE
1010 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
1011 if (!entry)
1012 return -ENOMEM;
1013 entry->c.text.read = snd_card_module_info_read;
1014 if (snd_info_register(entry) < 0)
1015 return -ENOMEM; /* freed in error path */
1016#endif
1017
1018 return 0;
1019}
1020#endif /* CONFIG_SND_PROC_FS */
1021
1022/**
1023 * snd_component_add - add a component string
1024 * @card: soundcard structure
1025 * @component: the component id string
1026 *
1027 * This function adds the component id string to the supported list.
1028 * The component can be referred from the alsa-lib.
1029 *
1030 * Return: Zero otherwise a negative error code.
1031 */
1032
1033int snd_component_add(struct snd_card *card, const char *component)
1034{
1035 char *ptr;
1036 int len = strlen(component);
1037
1038 ptr = strstr(card->components, component);
1039 if (ptr != NULL) {
1040 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
1041 return 1;
1042 }
1043 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
1044 snd_BUG();
1045 return -ENOMEM;
1046 }
1047 if (card->components[0] != '\0')
1048 strcat(card->components, " ");
1049 strcat(card->components, component);
1050 return 0;
1051}
1052EXPORT_SYMBOL(snd_component_add);
1053
1054/**
1055 * snd_card_file_add - add the file to the file list of the card
1056 * @card: soundcard structure
1057 * @file: file pointer
1058 *
1059 * This function adds the file to the file linked-list of the card.
1060 * This linked-list is used to keep tracking the connection state,
1061 * and to avoid the release of busy resources by hotplug.
1062 *
1063 * Return: zero or a negative error code.
1064 */
1065int snd_card_file_add(struct snd_card *card, struct file *file)
1066{
1067 struct snd_monitor_file *mfile;
1068
1069 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
1070 if (mfile == NULL)
1071 return -ENOMEM;
1072 mfile->file = file;
1073 mfile->disconnected_f_op = NULL;
1074 INIT_LIST_HEAD(&mfile->shutdown_list);
1075 spin_lock(&card->files_lock);
1076 if (card->shutdown) {
1077 spin_unlock(&card->files_lock);
1078 kfree(mfile);
1079 return -ENODEV;
1080 }
1081 list_add(&mfile->list, &card->files_list);
1082 get_device(&card->card_dev);
1083 spin_unlock(&card->files_lock);
1084 return 0;
1085}
1086EXPORT_SYMBOL(snd_card_file_add);
1087
1088/**
1089 * snd_card_file_remove - remove the file from the file list
1090 * @card: soundcard structure
1091 * @file: file pointer
1092 *
1093 * This function removes the file formerly added to the card via
1094 * snd_card_file_add() function.
1095 * If all files are removed and snd_card_free_when_closed() was
1096 * called beforehand, it processes the pending release of
1097 * resources.
1098 *
1099 * Return: Zero or a negative error code.
1100 */
1101int snd_card_file_remove(struct snd_card *card, struct file *file)
1102{
1103 struct snd_monitor_file *mfile, *found = NULL;
1104
1105 spin_lock(&card->files_lock);
1106 list_for_each_entry(mfile, &card->files_list, list) {
1107 if (mfile->file == file) {
1108 list_del(&mfile->list);
1109 spin_lock(&shutdown_lock);
1110 list_del(&mfile->shutdown_list);
1111 spin_unlock(&shutdown_lock);
1112 if (mfile->disconnected_f_op)
1113 fops_put(mfile->disconnected_f_op);
1114 found = mfile;
1115 break;
1116 }
1117 }
1118 if (list_empty(&card->files_list))
1119 wake_up_all(&card->remove_sleep);
1120 spin_unlock(&card->files_lock);
1121 if (!found) {
1122 dev_err(card->dev, "card file remove problem (%p)\n", file);
1123 return -ENOENT;
1124 }
1125 kfree(found);
1126 put_device(&card->card_dev);
1127 return 0;
1128}
1129EXPORT_SYMBOL(snd_card_file_remove);
1130
1131#ifdef CONFIG_PM
1132/**
1133 * snd_power_ref_and_wait - wait until the card gets powered up
1134 * @card: soundcard structure
1135 *
1136 * Take the power_ref reference count of the given card, and
1137 * wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1138 * The refcount is down again while sleeping until power-up, hence this
1139 * function can be used for syncing the floating control ops accesses,
1140 * typically around calling control ops.
1141 *
1142 * The caller needs to pull down the refcount via snd_power_unref() later
1143 * no matter whether the error is returned from this function or not.
1144 *
1145 * Return: Zero if successful, or a negative error code.
1146 */
1147int snd_power_ref_and_wait(struct snd_card *card)
1148{
1149 snd_power_ref(card);
1150 if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0)
1151 return 0;
1152 wait_event_cmd(card->power_sleep,
1153 card->shutdown ||
1154 snd_power_get_state(card) == SNDRV_CTL_POWER_D0,
1155 snd_power_unref(card), snd_power_ref(card));
1156 return card->shutdown ? -ENODEV : 0;
1157}
1158EXPORT_SYMBOL_GPL(snd_power_ref_and_wait);
1159
1160/**
1161 * snd_power_wait - wait until the card gets powered up (old form)
1162 * @card: soundcard structure
1163 *
1164 * Wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1165 *
1166 * Return: Zero if successful, or a negative error code.
1167 */
1168int snd_power_wait(struct snd_card *card)
1169{
1170 int ret;
1171
1172 ret = snd_power_ref_and_wait(card);
1173 snd_power_unref(card);
1174 return ret;
1175}
1176EXPORT_SYMBOL(snd_power_wait);
1177#endif /* CONFIG_PM */