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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/module.h>
25#include <linux/device.h>
26#include <linux/file.h>
27#include <linux/slab.h>
28#include <linux/time.h>
29#include <linux/ctype.h>
30#include <linux/pm.h>
31#include <linux/completion.h>
32
33#include <sound/core.h>
34#include <sound/control.h>
35#include <sound/info.h>
36
37/* monitor files for graceful shutdown (hotplug) */
38struct snd_monitor_file {
39 struct file *file;
40 const struct file_operations *disconnected_f_op;
41 struct list_head shutdown_list; /* still need to shutdown */
42 struct list_head list; /* link of monitor files */
43};
44
45static DEFINE_SPINLOCK(shutdown_lock);
46static LIST_HEAD(shutdown_files);
47
48static const struct file_operations snd_shutdown_f_ops;
49
50/* locked for registering/using */
51static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
52struct snd_card *snd_cards[SNDRV_CARDS];
53EXPORT_SYMBOL(snd_cards);
54
55static DEFINE_MUTEX(snd_card_mutex);
56
57static char *slots[SNDRV_CARDS];
58module_param_array(slots, charp, NULL, 0444);
59MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
60
61/* return non-zero if the given index is reserved for the given
62 * module via slots option
63 */
64static int module_slot_match(struct module *module, int idx)
65{
66 int match = 1;
67#ifdef MODULE
68 const char *s1, *s2;
69
70 if (!module || !*module->name || !slots[idx])
71 return 0;
72
73 s1 = module->name;
74 s2 = slots[idx];
75 if (*s2 == '!') {
76 match = 0; /* negative match */
77 s2++;
78 }
79 /* compare module name strings
80 * hyphens are handled as equivalent with underscore
81 */
82 for (;;) {
83 char c1 = *s1++;
84 char c2 = *s2++;
85 if (c1 == '-')
86 c1 = '_';
87 if (c2 == '-')
88 c2 = '_';
89 if (c1 != c2)
90 return !match;
91 if (!c1)
92 break;
93 }
94#endif /* MODULE */
95 return match;
96}
97
98#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
99int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
100EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
101#endif
102
103#ifdef CONFIG_PROC_FS
104static void snd_card_id_read(struct snd_info_entry *entry,
105 struct snd_info_buffer *buffer)
106{
107 snd_iprintf(buffer, "%s\n", entry->card->id);
108}
109
110static inline int init_info_for_card(struct snd_card *card)
111{
112 int err;
113 struct snd_info_entry *entry;
114
115 if ((err = snd_info_card_register(card)) < 0) {
116 dev_dbg(card->dev, "unable to create card info\n");
117 return err;
118 }
119 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
120 dev_dbg(card->dev, "unable to create card entry\n");
121 return err;
122 }
123 entry->c.text.read = snd_card_id_read;
124 if (snd_info_register(entry) < 0) {
125 snd_info_free_entry(entry);
126 entry = NULL;
127 }
128 card->proc_id = entry;
129 return 0;
130}
131#else /* !CONFIG_PROC_FS */
132#define init_info_for_card(card)
133#endif
134
135static int check_empty_slot(struct module *module, int slot)
136{
137 return !slots[slot] || !*slots[slot];
138}
139
140/* return an empty slot number (>= 0) found in the given bitmask @mask.
141 * @mask == -1 == 0xffffffff means: take any free slot up to 32
142 * when no slot is available, return the original @mask as is.
143 */
144static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
145 struct module *module)
146{
147 int slot;
148
149 for (slot = 0; slot < SNDRV_CARDS; slot++) {
150 if (slot < 32 && !(mask & (1U << slot)))
151 continue;
152 if (!test_bit(slot, snd_cards_lock)) {
153 if (check(module, slot))
154 return slot; /* found */
155 }
156 }
157 return mask; /* unchanged */
158}
159
160static int snd_card_do_free(struct snd_card *card);
161static const struct attribute_group *card_dev_attr_groups[];
162
163static void release_card_device(struct device *dev)
164{
165 snd_card_do_free(dev_to_snd_card(dev));
166}
167
168/**
169 * snd_card_new - create and initialize a soundcard structure
170 * @parent: the parent device object
171 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
172 * @xid: card identification (ASCII string)
173 * @module: top level module for locking
174 * @extra_size: allocate this extra size after the main soundcard structure
175 * @card_ret: the pointer to store the created card instance
176 *
177 * Creates and initializes a soundcard structure.
178 *
179 * The function allocates snd_card instance via kzalloc with the given
180 * space for the driver to use freely. The allocated struct is stored
181 * in the given card_ret pointer.
182 *
183 * Return: Zero if successful or a negative error code.
184 */
185int snd_card_new(struct device *parent, int idx, const char *xid,
186 struct module *module, int extra_size,
187 struct snd_card **card_ret)
188{
189 struct snd_card *card;
190 int err;
191
192 if (snd_BUG_ON(!card_ret))
193 return -EINVAL;
194 *card_ret = NULL;
195
196 if (extra_size < 0)
197 extra_size = 0;
198 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
199 if (!card)
200 return -ENOMEM;
201 if (extra_size > 0)
202 card->private_data = (char *)card + sizeof(struct snd_card);
203 if (xid)
204 strlcpy(card->id, xid, sizeof(card->id));
205 err = 0;
206 mutex_lock(&snd_card_mutex);
207 if (idx < 0) /* first check the matching module-name slot */
208 idx = get_slot_from_bitmask(idx, module_slot_match, module);
209 if (idx < 0) /* if not matched, assign an empty slot */
210 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
211 if (idx < 0)
212 err = -ENODEV;
213 else if (idx < snd_ecards_limit) {
214 if (test_bit(idx, snd_cards_lock))
215 err = -EBUSY; /* invalid */
216 } else if (idx >= SNDRV_CARDS)
217 err = -ENODEV;
218 if (err < 0) {
219 mutex_unlock(&snd_card_mutex);
220 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
221 idx, snd_ecards_limit - 1, err);
222 kfree(card);
223 return err;
224 }
225 set_bit(idx, snd_cards_lock); /* lock it */
226 if (idx >= snd_ecards_limit)
227 snd_ecards_limit = idx + 1; /* increase the limit */
228 mutex_unlock(&snd_card_mutex);
229 card->dev = parent;
230 card->number = idx;
231 card->module = module;
232 INIT_LIST_HEAD(&card->devices);
233 init_rwsem(&card->controls_rwsem);
234 rwlock_init(&card->ctl_files_rwlock);
235 INIT_LIST_HEAD(&card->controls);
236 INIT_LIST_HEAD(&card->ctl_files);
237 spin_lock_init(&card->files_lock);
238 INIT_LIST_HEAD(&card->files_list);
239#ifdef CONFIG_PM
240 mutex_init(&card->power_lock);
241 init_waitqueue_head(&card->power_sleep);
242#endif
243
244 device_initialize(&card->card_dev);
245 card->card_dev.parent = parent;
246 card->card_dev.class = sound_class;
247 card->card_dev.release = release_card_device;
248 card->card_dev.groups = card_dev_attr_groups;
249 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
250 if (err < 0)
251 goto __error;
252
253 /* the control interface cannot be accessed from the user space until */
254 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
255 err = snd_ctl_create(card);
256 if (err < 0) {
257 dev_err(parent, "unable to register control minors\n");
258 goto __error;
259 }
260 err = snd_info_card_create(card);
261 if (err < 0) {
262 dev_err(parent, "unable to create card info\n");
263 goto __error_ctl;
264 }
265 *card_ret = card;
266 return 0;
267
268 __error_ctl:
269 snd_device_free_all(card);
270 __error:
271 put_device(&card->card_dev);
272 return err;
273}
274EXPORT_SYMBOL(snd_card_new);
275
276/* return non-zero if a card is already locked */
277int snd_card_locked(int card)
278{
279 int locked;
280
281 mutex_lock(&snd_card_mutex);
282 locked = test_bit(card, snd_cards_lock);
283 mutex_unlock(&snd_card_mutex);
284 return locked;
285}
286
287static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
288{
289 return -ENODEV;
290}
291
292static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
293 size_t count, loff_t *offset)
294{
295 return -ENODEV;
296}
297
298static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
299 size_t count, loff_t *offset)
300{
301 return -ENODEV;
302}
303
304static int snd_disconnect_release(struct inode *inode, struct file *file)
305{
306 struct snd_monitor_file *df = NULL, *_df;
307
308 spin_lock(&shutdown_lock);
309 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
310 if (_df->file == file) {
311 df = _df;
312 list_del_init(&df->shutdown_list);
313 break;
314 }
315 }
316 spin_unlock(&shutdown_lock);
317
318 if (likely(df)) {
319 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
320 df->disconnected_f_op->fasync(-1, file, 0);
321 return df->disconnected_f_op->release(inode, file);
322 }
323
324 panic("%s(%p, %p) failed!", __func__, inode, file);
325}
326
327static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
328{
329 return POLLERR | POLLNVAL;
330}
331
332static long snd_disconnect_ioctl(struct file *file,
333 unsigned int cmd, unsigned long arg)
334{
335 return -ENODEV;
336}
337
338static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
339{
340 return -ENODEV;
341}
342
343static int snd_disconnect_fasync(int fd, struct file *file, int on)
344{
345 return -ENODEV;
346}
347
348static const struct file_operations snd_shutdown_f_ops =
349{
350 .owner = THIS_MODULE,
351 .llseek = snd_disconnect_llseek,
352 .read = snd_disconnect_read,
353 .write = snd_disconnect_write,
354 .release = snd_disconnect_release,
355 .poll = snd_disconnect_poll,
356 .unlocked_ioctl = snd_disconnect_ioctl,
357#ifdef CONFIG_COMPAT
358 .compat_ioctl = snd_disconnect_ioctl,
359#endif
360 .mmap = snd_disconnect_mmap,
361 .fasync = snd_disconnect_fasync
362};
363
364/**
365 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
366 * @card: soundcard structure
367 *
368 * Disconnects all APIs from the file-operations (user space).
369 *
370 * Return: Zero, otherwise a negative error code.
371 *
372 * Note: The current implementation replaces all active file->f_op with special
373 * dummy file operations (they do nothing except release).
374 */
375int snd_card_disconnect(struct snd_card *card)
376{
377 struct snd_monitor_file *mfile;
378 int err;
379
380 if (!card)
381 return -EINVAL;
382
383 spin_lock(&card->files_lock);
384 if (card->shutdown) {
385 spin_unlock(&card->files_lock);
386 return 0;
387 }
388 card->shutdown = 1;
389 spin_unlock(&card->files_lock);
390
391 /* phase 1: disable fops (user space) operations for ALSA API */
392 mutex_lock(&snd_card_mutex);
393 snd_cards[card->number] = NULL;
394 clear_bit(card->number, snd_cards_lock);
395 mutex_unlock(&snd_card_mutex);
396
397 /* phase 2: replace file->f_op with special dummy operations */
398
399 spin_lock(&card->files_lock);
400 list_for_each_entry(mfile, &card->files_list, list) {
401 /* it's critical part, use endless loop */
402 /* we have no room to fail */
403 mfile->disconnected_f_op = mfile->file->f_op;
404
405 spin_lock(&shutdown_lock);
406 list_add(&mfile->shutdown_list, &shutdown_files);
407 spin_unlock(&shutdown_lock);
408
409 mfile->file->f_op = &snd_shutdown_f_ops;
410 fops_get(mfile->file->f_op);
411 }
412 spin_unlock(&card->files_lock);
413
414 /* phase 3: notify all connected devices about disconnection */
415 /* at this point, they cannot respond to any calls except release() */
416
417#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
418 if (snd_mixer_oss_notify_callback)
419 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
420#endif
421
422 /* notify all devices that we are disconnected */
423 err = snd_device_disconnect_all(card);
424 if (err < 0)
425 dev_err(card->dev, "not all devices for card %i can be disconnected\n", card->number);
426
427 snd_info_card_disconnect(card);
428 if (card->registered) {
429 device_del(&card->card_dev);
430 card->registered = false;
431 }
432#ifdef CONFIG_PM
433 wake_up(&card->power_sleep);
434#endif
435 return 0;
436}
437
438EXPORT_SYMBOL(snd_card_disconnect);
439
440/**
441 * snd_card_free - frees given soundcard structure
442 * @card: soundcard structure
443 *
444 * This function releases the soundcard structure and the all assigned
445 * devices automatically. That is, you don't have to release the devices
446 * by yourself.
447 *
448 * Return: Zero. Frees all associated devices and frees the control
449 * interface associated to given soundcard.
450 */
451static int snd_card_do_free(struct snd_card *card)
452{
453#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
454 if (snd_mixer_oss_notify_callback)
455 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
456#endif
457 snd_device_free_all(card);
458 if (card->private_free)
459 card->private_free(card);
460 snd_info_free_entry(card->proc_id);
461 if (snd_info_card_free(card) < 0) {
462 dev_warn(card->dev, "unable to free card info\n");
463 /* Not fatal error */
464 }
465 if (card->release_completion)
466 complete(card->release_completion);
467 kfree(card);
468 return 0;
469}
470
471int snd_card_free_when_closed(struct snd_card *card)
472{
473 int ret = snd_card_disconnect(card);
474 if (ret)
475 return ret;
476 put_device(&card->card_dev);
477 return 0;
478}
479EXPORT_SYMBOL(snd_card_free_when_closed);
480
481int snd_card_free(struct snd_card *card)
482{
483 struct completion released;
484 int ret;
485
486 init_completion(&released);
487 card->release_completion = &released;
488 ret = snd_card_free_when_closed(card);
489 if (ret)
490 return ret;
491 /* wait, until all devices are ready for the free operation */
492 wait_for_completion(&released);
493 return 0;
494}
495EXPORT_SYMBOL(snd_card_free);
496
497/* retrieve the last word of shortname or longname */
498static const char *retrieve_id_from_card_name(const char *name)
499{
500 const char *spos = name;
501
502 while (*name) {
503 if (isspace(*name) && isalnum(name[1]))
504 spos = name + 1;
505 name++;
506 }
507 return spos;
508}
509
510/* return true if the given id string doesn't conflict any other card ids */
511static bool card_id_ok(struct snd_card *card, const char *id)
512{
513 int i;
514 if (!snd_info_check_reserved_words(id))
515 return false;
516 for (i = 0; i < snd_ecards_limit; i++) {
517 if (snd_cards[i] && snd_cards[i] != card &&
518 !strcmp(snd_cards[i]->id, id))
519 return false;
520 }
521 return true;
522}
523
524/* copy to card->id only with valid letters from nid */
525static void copy_valid_id_string(struct snd_card *card, const char *src,
526 const char *nid)
527{
528 char *id = card->id;
529
530 while (*nid && !isalnum(*nid))
531 nid++;
532 if (isdigit(*nid))
533 *id++ = isalpha(*src) ? *src : 'D';
534 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
535 if (isalnum(*nid))
536 *id++ = *nid;
537 nid++;
538 }
539 *id = 0;
540}
541
542/* Set card->id from the given string
543 * If the string conflicts with other ids, add a suffix to make it unique.
544 */
545static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
546 const char *nid)
547{
548 int len, loops;
549 bool is_default = false;
550 char *id;
551
552 copy_valid_id_string(card, src, nid);
553 id = card->id;
554
555 again:
556 /* use "Default" for obviously invalid strings
557 * ("card" conflicts with proc directories)
558 */
559 if (!*id || !strncmp(id, "card", 4)) {
560 strcpy(id, "Default");
561 is_default = true;
562 }
563
564 len = strlen(id);
565 for (loops = 0; loops < SNDRV_CARDS; loops++) {
566 char *spos;
567 char sfxstr[5]; /* "_012" */
568 int sfxlen;
569
570 if (card_id_ok(card, id))
571 return; /* OK */
572
573 /* Add _XYZ suffix */
574 sprintf(sfxstr, "_%X", loops + 1);
575 sfxlen = strlen(sfxstr);
576 if (len + sfxlen >= sizeof(card->id))
577 spos = id + sizeof(card->id) - sfxlen - 1;
578 else
579 spos = id + len;
580 strcpy(spos, sfxstr);
581 }
582 /* fallback to the default id */
583 if (!is_default) {
584 *id = 0;
585 goto again;
586 }
587 /* last resort... */
588 dev_err(card->dev, "unable to set card id (%s)\n", id);
589 if (card->proc_root->name)
590 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
591}
592
593/**
594 * snd_card_set_id - set card identification name
595 * @card: soundcard structure
596 * @nid: new identification string
597 *
598 * This function sets the card identification and checks for name
599 * collisions.
600 */
601void snd_card_set_id(struct snd_card *card, const char *nid)
602{
603 /* check if user specified own card->id */
604 if (card->id[0] != '\0')
605 return;
606 mutex_lock(&snd_card_mutex);
607 snd_card_set_id_no_lock(card, nid, nid);
608 mutex_unlock(&snd_card_mutex);
609}
610EXPORT_SYMBOL(snd_card_set_id);
611
612static ssize_t
613card_id_show_attr(struct device *dev,
614 struct device_attribute *attr, char *buf)
615{
616 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
617 return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
618}
619
620static ssize_t
621card_id_store_attr(struct device *dev, struct device_attribute *attr,
622 const char *buf, size_t count)
623{
624 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
625 char buf1[sizeof(card->id)];
626 size_t copy = count > sizeof(card->id) - 1 ?
627 sizeof(card->id) - 1 : count;
628 size_t idx;
629 int c;
630
631 for (idx = 0; idx < copy; idx++) {
632 c = buf[idx];
633 if (!isalnum(c) && c != '_' && c != '-')
634 return -EINVAL;
635 }
636 memcpy(buf1, buf, copy);
637 buf1[copy] = '\0';
638 mutex_lock(&snd_card_mutex);
639 if (!card_id_ok(NULL, buf1)) {
640 mutex_unlock(&snd_card_mutex);
641 return -EEXIST;
642 }
643 strcpy(card->id, buf1);
644 snd_info_card_id_change(card);
645 mutex_unlock(&snd_card_mutex);
646
647 return count;
648}
649
650static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
651
652static ssize_t
653card_number_show_attr(struct device *dev,
654 struct device_attribute *attr, char *buf)
655{
656 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
657 return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
658}
659
660static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
661
662static struct attribute *card_dev_attrs[] = {
663 &dev_attr_id.attr,
664 &dev_attr_number.attr,
665 NULL
666};
667
668static struct attribute_group card_dev_attr_group = {
669 .attrs = card_dev_attrs,
670};
671
672static const struct attribute_group *card_dev_attr_groups[] = {
673 &card_dev_attr_group,
674 NULL
675};
676
677/**
678 * snd_card_register - register the soundcard
679 * @card: soundcard structure
680 *
681 * This function registers all the devices assigned to the soundcard.
682 * Until calling this, the ALSA control interface is blocked from the
683 * external accesses. Thus, you should call this function at the end
684 * of the initialization of the card.
685 *
686 * Return: Zero otherwise a negative error code if the registration failed.
687 */
688int snd_card_register(struct snd_card *card)
689{
690 int err;
691
692 if (snd_BUG_ON(!card))
693 return -EINVAL;
694
695 if (!card->registered) {
696 err = device_add(&card->card_dev);
697 if (err < 0)
698 return err;
699 card->registered = true;
700 }
701
702 if ((err = snd_device_register_all(card)) < 0)
703 return err;
704 mutex_lock(&snd_card_mutex);
705 if (snd_cards[card->number]) {
706 /* already registered */
707 mutex_unlock(&snd_card_mutex);
708 return 0;
709 }
710 if (*card->id) {
711 /* make a unique id name from the given string */
712 char tmpid[sizeof(card->id)];
713 memcpy(tmpid, card->id, sizeof(card->id));
714 snd_card_set_id_no_lock(card, tmpid, tmpid);
715 } else {
716 /* create an id from either shortname or longname */
717 const char *src;
718 src = *card->shortname ? card->shortname : card->longname;
719 snd_card_set_id_no_lock(card, src,
720 retrieve_id_from_card_name(src));
721 }
722 snd_cards[card->number] = card;
723 mutex_unlock(&snd_card_mutex);
724 init_info_for_card(card);
725#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
726 if (snd_mixer_oss_notify_callback)
727 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
728#endif
729 return 0;
730}
731
732EXPORT_SYMBOL(snd_card_register);
733
734#ifdef CONFIG_PROC_FS
735static struct snd_info_entry *snd_card_info_entry;
736
737static void snd_card_info_read(struct snd_info_entry *entry,
738 struct snd_info_buffer *buffer)
739{
740 int idx, count;
741 struct snd_card *card;
742
743 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
744 mutex_lock(&snd_card_mutex);
745 if ((card = snd_cards[idx]) != NULL) {
746 count++;
747 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
748 idx,
749 card->id,
750 card->driver,
751 card->shortname);
752 snd_iprintf(buffer, " %s\n",
753 card->longname);
754 }
755 mutex_unlock(&snd_card_mutex);
756 }
757 if (!count)
758 snd_iprintf(buffer, "--- no soundcards ---\n");
759}
760
761#ifdef CONFIG_SND_OSSEMUL
762
763void snd_card_info_read_oss(struct snd_info_buffer *buffer)
764{
765 int idx, count;
766 struct snd_card *card;
767
768 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
769 mutex_lock(&snd_card_mutex);
770 if ((card = snd_cards[idx]) != NULL) {
771 count++;
772 snd_iprintf(buffer, "%s\n", card->longname);
773 }
774 mutex_unlock(&snd_card_mutex);
775 }
776 if (!count) {
777 snd_iprintf(buffer, "--- no soundcards ---\n");
778 }
779}
780
781#endif
782
783#ifdef MODULE
784static struct snd_info_entry *snd_card_module_info_entry;
785static void snd_card_module_info_read(struct snd_info_entry *entry,
786 struct snd_info_buffer *buffer)
787{
788 int idx;
789 struct snd_card *card;
790
791 for (idx = 0; idx < SNDRV_CARDS; idx++) {
792 mutex_lock(&snd_card_mutex);
793 if ((card = snd_cards[idx]) != NULL)
794 snd_iprintf(buffer, "%2i %s\n",
795 idx, card->module->name);
796 mutex_unlock(&snd_card_mutex);
797 }
798}
799#endif
800
801int __init snd_card_info_init(void)
802{
803 struct snd_info_entry *entry;
804
805 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
806 if (! entry)
807 return -ENOMEM;
808 entry->c.text.read = snd_card_info_read;
809 if (snd_info_register(entry) < 0) {
810 snd_info_free_entry(entry);
811 return -ENOMEM;
812 }
813 snd_card_info_entry = entry;
814
815#ifdef MODULE
816 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
817 if (entry) {
818 entry->c.text.read = snd_card_module_info_read;
819 if (snd_info_register(entry) < 0)
820 snd_info_free_entry(entry);
821 else
822 snd_card_module_info_entry = entry;
823 }
824#endif
825
826 return 0;
827}
828
829int __exit snd_card_info_done(void)
830{
831 snd_info_free_entry(snd_card_info_entry);
832#ifdef MODULE
833 snd_info_free_entry(snd_card_module_info_entry);
834#endif
835 return 0;
836}
837
838#endif /* CONFIG_PROC_FS */
839
840/**
841 * snd_component_add - add a component string
842 * @card: soundcard structure
843 * @component: the component id string
844 *
845 * This function adds the component id string to the supported list.
846 * The component can be referred from the alsa-lib.
847 *
848 * Return: Zero otherwise a negative error code.
849 */
850
851int snd_component_add(struct snd_card *card, const char *component)
852{
853 char *ptr;
854 int len = strlen(component);
855
856 ptr = strstr(card->components, component);
857 if (ptr != NULL) {
858 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
859 return 1;
860 }
861 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
862 snd_BUG();
863 return -ENOMEM;
864 }
865 if (card->components[0] != '\0')
866 strcat(card->components, " ");
867 strcat(card->components, component);
868 return 0;
869}
870
871EXPORT_SYMBOL(snd_component_add);
872
873/**
874 * snd_card_file_add - add the file to the file list of the card
875 * @card: soundcard structure
876 * @file: file pointer
877 *
878 * This function adds the file to the file linked-list of the card.
879 * This linked-list is used to keep tracking the connection state,
880 * and to avoid the release of busy resources by hotplug.
881 *
882 * Return: zero or a negative error code.
883 */
884int snd_card_file_add(struct snd_card *card, struct file *file)
885{
886 struct snd_monitor_file *mfile;
887
888 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
889 if (mfile == NULL)
890 return -ENOMEM;
891 mfile->file = file;
892 mfile->disconnected_f_op = NULL;
893 INIT_LIST_HEAD(&mfile->shutdown_list);
894 spin_lock(&card->files_lock);
895 if (card->shutdown) {
896 spin_unlock(&card->files_lock);
897 kfree(mfile);
898 return -ENODEV;
899 }
900 list_add(&mfile->list, &card->files_list);
901 get_device(&card->card_dev);
902 spin_unlock(&card->files_lock);
903 return 0;
904}
905
906EXPORT_SYMBOL(snd_card_file_add);
907
908/**
909 * snd_card_file_remove - remove the file from the file list
910 * @card: soundcard structure
911 * @file: file pointer
912 *
913 * This function removes the file formerly added to the card via
914 * snd_card_file_add() function.
915 * If all files are removed and snd_card_free_when_closed() was
916 * called beforehand, it processes the pending release of
917 * resources.
918 *
919 * Return: Zero or a negative error code.
920 */
921int snd_card_file_remove(struct snd_card *card, struct file *file)
922{
923 struct snd_monitor_file *mfile, *found = NULL;
924
925 spin_lock(&card->files_lock);
926 list_for_each_entry(mfile, &card->files_list, list) {
927 if (mfile->file == file) {
928 list_del(&mfile->list);
929 spin_lock(&shutdown_lock);
930 list_del(&mfile->shutdown_list);
931 spin_unlock(&shutdown_lock);
932 if (mfile->disconnected_f_op)
933 fops_put(mfile->disconnected_f_op);
934 found = mfile;
935 break;
936 }
937 }
938 spin_unlock(&card->files_lock);
939 if (!found) {
940 dev_err(card->dev, "card file remove problem (%p)\n", file);
941 return -ENOENT;
942 }
943 kfree(found);
944 put_device(&card->card_dev);
945 return 0;
946}
947
948EXPORT_SYMBOL(snd_card_file_remove);
949
950#ifdef CONFIG_PM
951/**
952 * snd_power_wait - wait until the power-state is changed.
953 * @card: soundcard structure
954 * @power_state: expected power state
955 *
956 * Waits until the power-state is changed.
957 *
958 * Return: Zero if successful, or a negative error code.
959 *
960 * Note: the power lock must be active before call.
961 */
962int snd_power_wait(struct snd_card *card, unsigned int power_state)
963{
964 wait_queue_t wait;
965 int result = 0;
966
967 /* fastpath */
968 if (snd_power_get_state(card) == power_state)
969 return 0;
970 init_waitqueue_entry(&wait, current);
971 add_wait_queue(&card->power_sleep, &wait);
972 while (1) {
973 if (card->shutdown) {
974 result = -ENODEV;
975 break;
976 }
977 if (snd_power_get_state(card) == power_state)
978 break;
979 set_current_state(TASK_UNINTERRUPTIBLE);
980 snd_power_unlock(card);
981 schedule_timeout(30 * HZ);
982 snd_power_lock(card);
983 }
984 remove_wait_queue(&card->power_sleep, &wait);
985 return result;
986}
987
988EXPORT_SYMBOL(snd_power_wait);
989#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_initialize() below;
115 * this is just NOP for now, as almost all jobs are already done in
116 * dev_free callback of snd_device chain instead.
117 */
118static void default_release(struct device *dev)
119{
120}
121
122/**
123 * snd_device_initialize - Initialize struct device for sound devices
124 * @dev: device to initialize
125 * @card: card to assign, optional
126 */
127void snd_device_initialize(struct device *dev, struct snd_card *card)
128{
129 device_initialize(dev);
130 if (card)
131 dev->parent = &card->card_dev;
132 dev->class = sound_class;
133 dev->release = default_release;
134}
135EXPORT_SYMBOL_GPL(snd_device_initialize);
136
137static int snd_card_do_free(struct snd_card *card);
138static const struct attribute_group card_dev_attr_group;
139
140static void release_card_device(struct device *dev)
141{
142 snd_card_do_free(dev_to_snd_card(dev));
143}
144
145/**
146 * snd_card_new - create and initialize a soundcard structure
147 * @parent: the parent device object
148 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
149 * @xid: card identification (ASCII string)
150 * @module: top level module for locking
151 * @extra_size: allocate this extra size after the main soundcard structure
152 * @card_ret: the pointer to store the created card instance
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#ifdef CONFIG_SND_DEBUG
167 char name[8];
168#endif
169
170 if (snd_BUG_ON(!card_ret))
171 return -EINVAL;
172 *card_ret = NULL;
173
174 if (extra_size < 0)
175 extra_size = 0;
176 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
177 if (!card)
178 return -ENOMEM;
179 if (extra_size > 0)
180 card->private_data = (char *)card + sizeof(struct snd_card);
181 if (xid)
182 strscpy(card->id, xid, sizeof(card->id));
183 err = 0;
184 mutex_lock(&snd_card_mutex);
185 if (idx < 0) /* first check the matching module-name slot */
186 idx = get_slot_from_bitmask(idx, module_slot_match, module);
187 if (idx < 0) /* if not matched, assign an empty slot */
188 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
189 if (idx < 0)
190 err = -ENODEV;
191 else if (idx < snd_ecards_limit) {
192 if (test_bit(idx, snd_cards_lock))
193 err = -EBUSY; /* invalid */
194 } else if (idx >= SNDRV_CARDS)
195 err = -ENODEV;
196 if (err < 0) {
197 mutex_unlock(&snd_card_mutex);
198 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
199 idx, snd_ecards_limit - 1, err);
200 kfree(card);
201 return err;
202 }
203 set_bit(idx, snd_cards_lock); /* lock it */
204 if (idx >= snd_ecards_limit)
205 snd_ecards_limit = idx + 1; /* increase the limit */
206 mutex_unlock(&snd_card_mutex);
207 card->dev = parent;
208 card->number = idx;
209#ifdef MODULE
210 WARN_ON(!module);
211 card->module = module;
212#endif
213 INIT_LIST_HEAD(&card->devices);
214 init_rwsem(&card->controls_rwsem);
215 rwlock_init(&card->ctl_files_rwlock);
216 INIT_LIST_HEAD(&card->controls);
217 INIT_LIST_HEAD(&card->ctl_files);
218 spin_lock_init(&card->files_lock);
219 INIT_LIST_HEAD(&card->files_list);
220 mutex_init(&card->memory_mutex);
221#ifdef CONFIG_PM
222 init_waitqueue_head(&card->power_sleep);
223 init_waitqueue_head(&card->power_ref_sleep);
224 atomic_set(&card->power_ref, 0);
225#endif
226 init_waitqueue_head(&card->remove_sleep);
227 card->sync_irq = -1;
228
229 device_initialize(&card->card_dev);
230 card->card_dev.parent = parent;
231 card->card_dev.class = sound_class;
232 card->card_dev.release = release_card_device;
233 card->card_dev.groups = card->dev_groups;
234 card->dev_groups[0] = &card_dev_attr_group;
235 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
236 if (err < 0)
237 goto __error;
238
239 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
240 dev_driver_string(card->dev), dev_name(&card->card_dev));
241
242 /* the control interface cannot be accessed from the user space until */
243 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
244 err = snd_ctl_create(card);
245 if (err < 0) {
246 dev_err(parent, "unable to register control minors\n");
247 goto __error;
248 }
249 err = snd_info_card_create(card);
250 if (err < 0) {
251 dev_err(parent, "unable to create card info\n");
252 goto __error_ctl;
253 }
254
255#ifdef CONFIG_SND_DEBUG
256 sprintf(name, "card%d", idx);
257 card->debugfs_root = debugfs_create_dir(name, sound_debugfs_root);
258#endif
259
260 *card_ret = card;
261 return 0;
262
263 __error_ctl:
264 snd_device_free_all(card);
265 __error:
266 put_device(&card->card_dev);
267 return err;
268}
269EXPORT_SYMBOL(snd_card_new);
270
271/**
272 * snd_card_ref - Get the card object from the index
273 * @idx: the card index
274 *
275 * Returns a card object corresponding to the given index or NULL if not found.
276 * Release the object via snd_card_unref().
277 */
278struct snd_card *snd_card_ref(int idx)
279{
280 struct snd_card *card;
281
282 mutex_lock(&snd_card_mutex);
283 card = snd_cards[idx];
284 if (card)
285 get_device(&card->card_dev);
286 mutex_unlock(&snd_card_mutex);
287 return card;
288}
289EXPORT_SYMBOL_GPL(snd_card_ref);
290
291/* return non-zero if a card is already locked */
292int snd_card_locked(int card)
293{
294 int locked;
295
296 mutex_lock(&snd_card_mutex);
297 locked = test_bit(card, snd_cards_lock);
298 mutex_unlock(&snd_card_mutex);
299 return locked;
300}
301
302static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
303{
304 return -ENODEV;
305}
306
307static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
308 size_t count, loff_t *offset)
309{
310 return -ENODEV;
311}
312
313static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
314 size_t count, loff_t *offset)
315{
316 return -ENODEV;
317}
318
319static int snd_disconnect_release(struct inode *inode, struct file *file)
320{
321 struct snd_monitor_file *df = NULL, *_df;
322
323 spin_lock(&shutdown_lock);
324 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
325 if (_df->file == file) {
326 df = _df;
327 list_del_init(&df->shutdown_list);
328 break;
329 }
330 }
331 spin_unlock(&shutdown_lock);
332
333 if (likely(df)) {
334 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
335 df->disconnected_f_op->fasync(-1, file, 0);
336 return df->disconnected_f_op->release(inode, file);
337 }
338
339 panic("%s(%p, %p) failed!", __func__, inode, file);
340}
341
342static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
343{
344 return EPOLLERR | EPOLLNVAL;
345}
346
347static long snd_disconnect_ioctl(struct file *file,
348 unsigned int cmd, unsigned long arg)
349{
350 return -ENODEV;
351}
352
353static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
354{
355 return -ENODEV;
356}
357
358static int snd_disconnect_fasync(int fd, struct file *file, int on)
359{
360 return -ENODEV;
361}
362
363static const struct file_operations snd_shutdown_f_ops =
364{
365 .owner = THIS_MODULE,
366 .llseek = snd_disconnect_llseek,
367 .read = snd_disconnect_read,
368 .write = snd_disconnect_write,
369 .release = snd_disconnect_release,
370 .poll = snd_disconnect_poll,
371 .unlocked_ioctl = snd_disconnect_ioctl,
372#ifdef CONFIG_COMPAT
373 .compat_ioctl = snd_disconnect_ioctl,
374#endif
375 .mmap = snd_disconnect_mmap,
376 .fasync = snd_disconnect_fasync
377};
378
379/**
380 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
381 * @card: soundcard structure
382 *
383 * Disconnects all APIs from the file-operations (user space).
384 *
385 * Return: Zero, otherwise a negative error code.
386 *
387 * Note: The current implementation replaces all active file->f_op with special
388 * dummy file operations (they do nothing except release).
389 */
390int snd_card_disconnect(struct snd_card *card)
391{
392 struct snd_monitor_file *mfile;
393
394 if (!card)
395 return -EINVAL;
396
397 spin_lock(&card->files_lock);
398 if (card->shutdown) {
399 spin_unlock(&card->files_lock);
400 return 0;
401 }
402 card->shutdown = 1;
403
404 /* replace file->f_op with special dummy operations */
405 list_for_each_entry(mfile, &card->files_list, list) {
406 /* it's critical part, use endless loop */
407 /* we have no room to fail */
408 mfile->disconnected_f_op = mfile->file->f_op;
409
410 spin_lock(&shutdown_lock);
411 list_add(&mfile->shutdown_list, &shutdown_files);
412 spin_unlock(&shutdown_lock);
413
414 mfile->file->f_op = &snd_shutdown_f_ops;
415 fops_get(mfile->file->f_op);
416 }
417 spin_unlock(&card->files_lock);
418
419 /* notify all connected devices about disconnection */
420 /* at this point, they cannot respond to any calls except release() */
421
422#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
423 if (snd_mixer_oss_notify_callback)
424 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
425#endif
426
427 /* notify all devices that we are disconnected */
428 snd_device_disconnect_all(card);
429
430 if (card->sync_irq > 0)
431 synchronize_irq(card->sync_irq);
432
433 snd_info_card_disconnect(card);
434 if (card->registered) {
435 device_del(&card->card_dev);
436 card->registered = false;
437 }
438
439 /* disable fops (user space) operations for ALSA API */
440 mutex_lock(&snd_card_mutex);
441 snd_cards[card->number] = NULL;
442 clear_bit(card->number, snd_cards_lock);
443 mutex_unlock(&snd_card_mutex);
444
445#ifdef CONFIG_PM
446 wake_up(&card->power_sleep);
447 snd_power_sync_ref(card);
448#endif
449 return 0;
450}
451EXPORT_SYMBOL(snd_card_disconnect);
452
453/**
454 * snd_card_disconnect_sync - disconnect card and wait until files get closed
455 * @card: card object to disconnect
456 *
457 * This calls snd_card_disconnect() for disconnecting all belonging components
458 * and waits until all pending files get closed.
459 * It assures that all accesses from user-space finished so that the driver
460 * can release its resources gracefully.
461 */
462void snd_card_disconnect_sync(struct snd_card *card)
463{
464 int err;
465
466 err = snd_card_disconnect(card);
467 if (err < 0) {
468 dev_err(card->dev,
469 "snd_card_disconnect error (%d), skipping sync\n",
470 err);
471 return;
472 }
473
474 spin_lock_irq(&card->files_lock);
475 wait_event_lock_irq(card->remove_sleep,
476 list_empty(&card->files_list),
477 card->files_lock);
478 spin_unlock_irq(&card->files_lock);
479}
480EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
481
482static int snd_card_do_free(struct snd_card *card)
483{
484#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
485 if (snd_mixer_oss_notify_callback)
486 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
487#endif
488 snd_device_free_all(card);
489 if (card->private_free)
490 card->private_free(card);
491 if (snd_info_card_free(card) < 0) {
492 dev_warn(card->dev, "unable to free card info\n");
493 /* Not fatal error */
494 }
495#ifdef CONFIG_SND_DEBUG
496 debugfs_remove(card->debugfs_root);
497 card->debugfs_root = NULL;
498#endif
499 if (card->release_completion)
500 complete(card->release_completion);
501 kfree(card);
502 return 0;
503}
504
505/**
506 * snd_card_free_when_closed - Disconnect the card, free it later eventually
507 * @card: soundcard structure
508 *
509 * Unlike snd_card_free(), this function doesn't try to release the card
510 * resource immediately, but tries to disconnect at first. When the card
511 * is still in use, the function returns before freeing the resources.
512 * The card resources will be freed when the refcount gets to zero.
513 */
514int snd_card_free_when_closed(struct snd_card *card)
515{
516 int ret = snd_card_disconnect(card);
517 if (ret)
518 return ret;
519 put_device(&card->card_dev);
520 return 0;
521}
522EXPORT_SYMBOL(snd_card_free_when_closed);
523
524/**
525 * snd_card_free - frees given soundcard structure
526 * @card: soundcard structure
527 *
528 * This function releases the soundcard structure and the all assigned
529 * devices automatically. That is, you don't have to release the devices
530 * by yourself.
531 *
532 * This function waits until the all resources are properly released.
533 *
534 * Return: Zero. Frees all associated devices and frees the control
535 * interface associated to given soundcard.
536 */
537int snd_card_free(struct snd_card *card)
538{
539 DECLARE_COMPLETION_ONSTACK(released);
540 int ret;
541
542 card->release_completion = &released;
543 ret = snd_card_free_when_closed(card);
544 if (ret)
545 return ret;
546 /* wait, until all devices are ready for the free operation */
547 wait_for_completion(&released);
548
549 return 0;
550}
551EXPORT_SYMBOL(snd_card_free);
552
553/* retrieve the last word of shortname or longname */
554static const char *retrieve_id_from_card_name(const char *name)
555{
556 const char *spos = name;
557
558 while (*name) {
559 if (isspace(*name) && isalnum(name[1]))
560 spos = name + 1;
561 name++;
562 }
563 return spos;
564}
565
566/* return true if the given id string doesn't conflict any other card ids */
567static bool card_id_ok(struct snd_card *card, const char *id)
568{
569 int i;
570 if (!snd_info_check_reserved_words(id))
571 return false;
572 for (i = 0; i < snd_ecards_limit; i++) {
573 if (snd_cards[i] && snd_cards[i] != card &&
574 !strcmp(snd_cards[i]->id, id))
575 return false;
576 }
577 return true;
578}
579
580/* copy to card->id only with valid letters from nid */
581static void copy_valid_id_string(struct snd_card *card, const char *src,
582 const char *nid)
583{
584 char *id = card->id;
585
586 while (*nid && !isalnum(*nid))
587 nid++;
588 if (isdigit(*nid))
589 *id++ = isalpha(*src) ? *src : 'D';
590 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
591 if (isalnum(*nid))
592 *id++ = *nid;
593 nid++;
594 }
595 *id = 0;
596}
597
598/* Set card->id from the given string
599 * If the string conflicts with other ids, add a suffix to make it unique.
600 */
601static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
602 const char *nid)
603{
604 int len, loops;
605 bool is_default = false;
606 char *id;
607
608 copy_valid_id_string(card, src, nid);
609 id = card->id;
610
611 again:
612 /* use "Default" for obviously invalid strings
613 * ("card" conflicts with proc directories)
614 */
615 if (!*id || !strncmp(id, "card", 4)) {
616 strcpy(id, "Default");
617 is_default = true;
618 }
619
620 len = strlen(id);
621 for (loops = 0; loops < SNDRV_CARDS; loops++) {
622 char *spos;
623 char sfxstr[5]; /* "_012" */
624 int sfxlen;
625
626 if (card_id_ok(card, id))
627 return; /* OK */
628
629 /* Add _XYZ suffix */
630 sprintf(sfxstr, "_%X", loops + 1);
631 sfxlen = strlen(sfxstr);
632 if (len + sfxlen >= sizeof(card->id))
633 spos = id + sizeof(card->id) - sfxlen - 1;
634 else
635 spos = id + len;
636 strcpy(spos, sfxstr);
637 }
638 /* fallback to the default id */
639 if (!is_default) {
640 *id = 0;
641 goto again;
642 }
643 /* last resort... */
644 dev_err(card->dev, "unable to set card id (%s)\n", id);
645 if (card->proc_root->name)
646 strscpy(card->id, card->proc_root->name, sizeof(card->id));
647}
648
649/**
650 * snd_card_set_id - set card identification name
651 * @card: soundcard structure
652 * @nid: new identification string
653 *
654 * This function sets the card identification and checks for name
655 * collisions.
656 */
657void snd_card_set_id(struct snd_card *card, const char *nid)
658{
659 /* check if user specified own card->id */
660 if (card->id[0] != '\0')
661 return;
662 mutex_lock(&snd_card_mutex);
663 snd_card_set_id_no_lock(card, nid, nid);
664 mutex_unlock(&snd_card_mutex);
665}
666EXPORT_SYMBOL(snd_card_set_id);
667
668static ssize_t id_show(struct device *dev,
669 struct device_attribute *attr, char *buf)
670{
671 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
672 return scnprintf(buf, PAGE_SIZE, "%s\n", card->id);
673}
674
675static ssize_t id_store(struct device *dev, struct device_attribute *attr,
676 const char *buf, size_t count)
677{
678 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
679 char buf1[sizeof(card->id)];
680 size_t copy = count > sizeof(card->id) - 1 ?
681 sizeof(card->id) - 1 : count;
682 size_t idx;
683 int c;
684
685 for (idx = 0; idx < copy; idx++) {
686 c = buf[idx];
687 if (!isalnum(c) && c != '_' && c != '-')
688 return -EINVAL;
689 }
690 memcpy(buf1, buf, copy);
691 buf1[copy] = '\0';
692 mutex_lock(&snd_card_mutex);
693 if (!card_id_ok(NULL, buf1)) {
694 mutex_unlock(&snd_card_mutex);
695 return -EEXIST;
696 }
697 strcpy(card->id, buf1);
698 snd_info_card_id_change(card);
699 mutex_unlock(&snd_card_mutex);
700
701 return count;
702}
703
704static DEVICE_ATTR_RW(id);
705
706static ssize_t number_show(struct device *dev,
707 struct device_attribute *attr, char *buf)
708{
709 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
710 return scnprintf(buf, PAGE_SIZE, "%i\n", card->number);
711}
712
713static DEVICE_ATTR_RO(number);
714
715static struct attribute *card_dev_attrs[] = {
716 &dev_attr_id.attr,
717 &dev_attr_number.attr,
718 NULL
719};
720
721static const struct attribute_group card_dev_attr_group = {
722 .attrs = card_dev_attrs,
723};
724
725/**
726 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
727 * @card: card instance
728 * @group: attribute group to append
729 */
730int snd_card_add_dev_attr(struct snd_card *card,
731 const struct attribute_group *group)
732{
733 int i;
734
735 /* loop for (arraysize-1) here to keep NULL at the last entry */
736 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
737 if (!card->dev_groups[i]) {
738 card->dev_groups[i] = group;
739 return 0;
740 }
741 }
742
743 dev_err(card->dev, "Too many groups assigned\n");
744 return -ENOSPC;
745}
746EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
747
748/**
749 * snd_card_register - register the soundcard
750 * @card: soundcard structure
751 *
752 * This function registers all the devices assigned to the soundcard.
753 * Until calling this, the ALSA control interface is blocked from the
754 * external accesses. Thus, you should call this function at the end
755 * of the initialization of the card.
756 *
757 * Return: Zero otherwise a negative error code if the registration failed.
758 */
759int snd_card_register(struct snd_card *card)
760{
761 int err;
762
763 if (snd_BUG_ON(!card))
764 return -EINVAL;
765
766 if (!card->registered) {
767 err = device_add(&card->card_dev);
768 if (err < 0)
769 return err;
770 card->registered = true;
771 }
772
773 err = snd_device_register_all(card);
774 if (err < 0)
775 return err;
776 mutex_lock(&snd_card_mutex);
777 if (snd_cards[card->number]) {
778 /* already registered */
779 mutex_unlock(&snd_card_mutex);
780 return snd_info_card_register(card); /* register pending info */
781 }
782 if (*card->id) {
783 /* make a unique id name from the given string */
784 char tmpid[sizeof(card->id)];
785 memcpy(tmpid, card->id, sizeof(card->id));
786 snd_card_set_id_no_lock(card, tmpid, tmpid);
787 } else {
788 /* create an id from either shortname or longname */
789 const char *src;
790 src = *card->shortname ? card->shortname : card->longname;
791 snd_card_set_id_no_lock(card, src,
792 retrieve_id_from_card_name(src));
793 }
794 snd_cards[card->number] = card;
795 mutex_unlock(&snd_card_mutex);
796 err = snd_info_card_register(card);
797 if (err < 0)
798 return err;
799
800#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
801 if (snd_mixer_oss_notify_callback)
802 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
803#endif
804 return 0;
805}
806EXPORT_SYMBOL(snd_card_register);
807
808#ifdef CONFIG_SND_PROC_FS
809static void snd_card_info_read(struct snd_info_entry *entry,
810 struct snd_info_buffer *buffer)
811{
812 int idx, count;
813 struct snd_card *card;
814
815 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
816 mutex_lock(&snd_card_mutex);
817 card = snd_cards[idx];
818 if (card) {
819 count++;
820 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
821 idx,
822 card->id,
823 card->driver,
824 card->shortname);
825 snd_iprintf(buffer, " %s\n",
826 card->longname);
827 }
828 mutex_unlock(&snd_card_mutex);
829 }
830 if (!count)
831 snd_iprintf(buffer, "--- no soundcards ---\n");
832}
833
834#ifdef CONFIG_SND_OSSEMUL
835void snd_card_info_read_oss(struct snd_info_buffer *buffer)
836{
837 int idx, count;
838 struct snd_card *card;
839
840 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
841 mutex_lock(&snd_card_mutex);
842 card = snd_cards[idx];
843 if (card) {
844 count++;
845 snd_iprintf(buffer, "%s\n", card->longname);
846 }
847 mutex_unlock(&snd_card_mutex);
848 }
849 if (!count) {
850 snd_iprintf(buffer, "--- no soundcards ---\n");
851 }
852}
853
854#endif
855
856#ifdef MODULE
857static void snd_card_module_info_read(struct snd_info_entry *entry,
858 struct snd_info_buffer *buffer)
859{
860 int idx;
861 struct snd_card *card;
862
863 for (idx = 0; idx < SNDRV_CARDS; idx++) {
864 mutex_lock(&snd_card_mutex);
865 card = snd_cards[idx];
866 if (card)
867 snd_iprintf(buffer, "%2i %s\n",
868 idx, card->module->name);
869 mutex_unlock(&snd_card_mutex);
870 }
871}
872#endif
873
874int __init snd_card_info_init(void)
875{
876 struct snd_info_entry *entry;
877
878 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
879 if (! entry)
880 return -ENOMEM;
881 entry->c.text.read = snd_card_info_read;
882 if (snd_info_register(entry) < 0)
883 return -ENOMEM; /* freed in error path */
884
885#ifdef MODULE
886 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
887 if (!entry)
888 return -ENOMEM;
889 entry->c.text.read = snd_card_module_info_read;
890 if (snd_info_register(entry) < 0)
891 return -ENOMEM; /* freed in error path */
892#endif
893
894 return 0;
895}
896#endif /* CONFIG_SND_PROC_FS */
897
898/**
899 * snd_component_add - add a component string
900 * @card: soundcard structure
901 * @component: the component id string
902 *
903 * This function adds the component id string to the supported list.
904 * The component can be referred from the alsa-lib.
905 *
906 * Return: Zero otherwise a negative error code.
907 */
908
909int snd_component_add(struct snd_card *card, const char *component)
910{
911 char *ptr;
912 int len = strlen(component);
913
914 ptr = strstr(card->components, component);
915 if (ptr != NULL) {
916 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
917 return 1;
918 }
919 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
920 snd_BUG();
921 return -ENOMEM;
922 }
923 if (card->components[0] != '\0')
924 strcat(card->components, " ");
925 strcat(card->components, component);
926 return 0;
927}
928EXPORT_SYMBOL(snd_component_add);
929
930/**
931 * snd_card_file_add - add the file to the file list of the card
932 * @card: soundcard structure
933 * @file: file pointer
934 *
935 * This function adds the file to the file linked-list of the card.
936 * This linked-list is used to keep tracking the connection state,
937 * and to avoid the release of busy resources by hotplug.
938 *
939 * Return: zero or a negative error code.
940 */
941int snd_card_file_add(struct snd_card *card, struct file *file)
942{
943 struct snd_monitor_file *mfile;
944
945 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
946 if (mfile == NULL)
947 return -ENOMEM;
948 mfile->file = file;
949 mfile->disconnected_f_op = NULL;
950 INIT_LIST_HEAD(&mfile->shutdown_list);
951 spin_lock(&card->files_lock);
952 if (card->shutdown) {
953 spin_unlock(&card->files_lock);
954 kfree(mfile);
955 return -ENODEV;
956 }
957 list_add(&mfile->list, &card->files_list);
958 get_device(&card->card_dev);
959 spin_unlock(&card->files_lock);
960 return 0;
961}
962EXPORT_SYMBOL(snd_card_file_add);
963
964/**
965 * snd_card_file_remove - remove the file from the file list
966 * @card: soundcard structure
967 * @file: file pointer
968 *
969 * This function removes the file formerly added to the card via
970 * snd_card_file_add() function.
971 * If all files are removed and snd_card_free_when_closed() was
972 * called beforehand, it processes the pending release of
973 * resources.
974 *
975 * Return: Zero or a negative error code.
976 */
977int snd_card_file_remove(struct snd_card *card, struct file *file)
978{
979 struct snd_monitor_file *mfile, *found = NULL;
980
981 spin_lock(&card->files_lock);
982 list_for_each_entry(mfile, &card->files_list, list) {
983 if (mfile->file == file) {
984 list_del(&mfile->list);
985 spin_lock(&shutdown_lock);
986 list_del(&mfile->shutdown_list);
987 spin_unlock(&shutdown_lock);
988 if (mfile->disconnected_f_op)
989 fops_put(mfile->disconnected_f_op);
990 found = mfile;
991 break;
992 }
993 }
994 if (list_empty(&card->files_list))
995 wake_up_all(&card->remove_sleep);
996 spin_unlock(&card->files_lock);
997 if (!found) {
998 dev_err(card->dev, "card file remove problem (%p)\n", file);
999 return -ENOENT;
1000 }
1001 kfree(found);
1002 put_device(&card->card_dev);
1003 return 0;
1004}
1005EXPORT_SYMBOL(snd_card_file_remove);
1006
1007#ifdef CONFIG_PM
1008/**
1009 * snd_power_ref_and_wait - wait until the card gets powered up
1010 * @card: soundcard structure
1011 *
1012 * Take the power_ref reference count of the given card, and
1013 * wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1014 * The refcount is down again while sleeping until power-up, hence this
1015 * function can be used for syncing the floating control ops accesses,
1016 * typically around calling control ops.
1017 *
1018 * The caller needs to pull down the refcount via snd_power_unref() later
1019 * no matter whether the error is returned from this function or not.
1020 *
1021 * Return: Zero if successful, or a negative error code.
1022 */
1023int snd_power_ref_and_wait(struct snd_card *card)
1024{
1025 wait_queue_entry_t wait;
1026 int result = 0;
1027
1028 snd_power_ref(card);
1029 /* fastpath */
1030 if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0)
1031 return 0;
1032 init_waitqueue_entry(&wait, current);
1033 add_wait_queue(&card->power_sleep, &wait);
1034 while (1) {
1035 if (card->shutdown) {
1036 result = -ENODEV;
1037 break;
1038 }
1039 if (snd_power_get_state(card) == SNDRV_CTL_POWER_D0)
1040 break;
1041 snd_power_unref(card);
1042 set_current_state(TASK_UNINTERRUPTIBLE);
1043 schedule_timeout(30 * HZ);
1044 snd_power_ref(card);
1045 }
1046 remove_wait_queue(&card->power_sleep, &wait);
1047 return result;
1048}
1049EXPORT_SYMBOL_GPL(snd_power_ref_and_wait);
1050
1051/**
1052 * snd_power_wait - wait until the card gets powered up (old form)
1053 * @card: soundcard structure
1054 *
1055 * Wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1056 *
1057 * Return: Zero if successful, or a negative error code.
1058 */
1059int snd_power_wait(struct snd_card *card)
1060{
1061 int ret;
1062
1063 ret = snd_power_ref_and_wait(card);
1064 snd_power_unref(card);
1065 return ret;
1066}
1067EXPORT_SYMBOL(snd_power_wait);
1068#endif /* CONFIG_PM */