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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_SND_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 int init_info_for_card(struct snd_card *card)
111{
112 struct snd_info_entry *entry;
113
114 entry = snd_info_create_card_entry(card, "id", card->proc_root);
115 if (!entry) {
116 dev_dbg(card->dev, "unable to create card entry\n");
117 return -ENOMEM;
118 }
119 entry->c.text.read = snd_card_id_read;
120 card->proc_id = entry;
121
122 return snd_info_card_register(card);
123}
124#else /* !CONFIG_SND_PROC_FS */
125#define init_info_for_card(card)
126#endif
127
128static int check_empty_slot(struct module *module, int slot)
129{
130 return !slots[slot] || !*slots[slot];
131}
132
133/* return an empty slot number (>= 0) found in the given bitmask @mask.
134 * @mask == -1 == 0xffffffff means: take any free slot up to 32
135 * when no slot is available, return the original @mask as is.
136 */
137static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
138 struct module *module)
139{
140 int slot;
141
142 for (slot = 0; slot < SNDRV_CARDS; slot++) {
143 if (slot < 32 && !(mask & (1U << slot)))
144 continue;
145 if (!test_bit(slot, snd_cards_lock)) {
146 if (check(module, slot))
147 return slot; /* found */
148 }
149 }
150 return mask; /* unchanged */
151}
152
153/* the default release callback set in snd_device_initialize() below;
154 * this is just NOP for now, as almost all jobs are already done in
155 * dev_free callback of snd_device chain instead.
156 */
157static void default_release(struct device *dev)
158{
159}
160
161/**
162 * snd_device_initialize - Initialize struct device for sound devices
163 * @dev: device to initialize
164 * @card: card to assign, optional
165 */
166void snd_device_initialize(struct device *dev, struct snd_card *card)
167{
168 device_initialize(dev);
169 if (card)
170 dev->parent = &card->card_dev;
171 dev->class = sound_class;
172 dev->release = default_release;
173}
174EXPORT_SYMBOL_GPL(snd_device_initialize);
175
176static int snd_card_do_free(struct snd_card *card);
177static const struct attribute_group card_dev_attr_group;
178
179static void release_card_device(struct device *dev)
180{
181 snd_card_do_free(dev_to_snd_card(dev));
182}
183
184/**
185 * snd_card_new - create and initialize a soundcard structure
186 * @parent: the parent device object
187 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
188 * @xid: card identification (ASCII string)
189 * @module: top level module for locking
190 * @extra_size: allocate this extra size after the main soundcard structure
191 * @card_ret: the pointer to store the created card instance
192 *
193 * Creates and initializes a soundcard structure.
194 *
195 * The function allocates snd_card instance via kzalloc with the given
196 * space for the driver to use freely. The allocated struct is stored
197 * in the given card_ret pointer.
198 *
199 * Return: Zero if successful or a negative error code.
200 */
201int snd_card_new(struct device *parent, int idx, const char *xid,
202 struct module *module, int extra_size,
203 struct snd_card **card_ret)
204{
205 struct snd_card *card;
206 int err;
207
208 if (snd_BUG_ON(!card_ret))
209 return -EINVAL;
210 *card_ret = NULL;
211
212 if (extra_size < 0)
213 extra_size = 0;
214 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
215 if (!card)
216 return -ENOMEM;
217 if (extra_size > 0)
218 card->private_data = (char *)card + sizeof(struct snd_card);
219 if (xid)
220 strlcpy(card->id, xid, sizeof(card->id));
221 err = 0;
222 mutex_lock(&snd_card_mutex);
223 if (idx < 0) /* first check the matching module-name slot */
224 idx = get_slot_from_bitmask(idx, module_slot_match, module);
225 if (idx < 0) /* if not matched, assign an empty slot */
226 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
227 if (idx < 0)
228 err = -ENODEV;
229 else if (idx < snd_ecards_limit) {
230 if (test_bit(idx, snd_cards_lock))
231 err = -EBUSY; /* invalid */
232 } else if (idx >= SNDRV_CARDS)
233 err = -ENODEV;
234 if (err < 0) {
235 mutex_unlock(&snd_card_mutex);
236 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
237 idx, snd_ecards_limit - 1, err);
238 kfree(card);
239 return err;
240 }
241 set_bit(idx, snd_cards_lock); /* lock it */
242 if (idx >= snd_ecards_limit)
243 snd_ecards_limit = idx + 1; /* increase the limit */
244 mutex_unlock(&snd_card_mutex);
245 card->dev = parent;
246 card->number = idx;
247 card->module = module;
248 INIT_LIST_HEAD(&card->devices);
249 init_rwsem(&card->controls_rwsem);
250 rwlock_init(&card->ctl_files_rwlock);
251 mutex_init(&card->user_ctl_lock);
252 INIT_LIST_HEAD(&card->controls);
253 INIT_LIST_HEAD(&card->ctl_files);
254 spin_lock_init(&card->files_lock);
255 INIT_LIST_HEAD(&card->files_list);
256#ifdef CONFIG_PM
257 mutex_init(&card->power_lock);
258 init_waitqueue_head(&card->power_sleep);
259#endif
260
261 device_initialize(&card->card_dev);
262 card->card_dev.parent = parent;
263 card->card_dev.class = sound_class;
264 card->card_dev.release = release_card_device;
265 card->card_dev.groups = card->dev_groups;
266 card->dev_groups[0] = &card_dev_attr_group;
267 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
268 if (err < 0)
269 goto __error;
270
271 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
272 dev_driver_string(card->dev), dev_name(&card->card_dev));
273
274 /* the control interface cannot be accessed from the user space until */
275 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
276 err = snd_ctl_create(card);
277 if (err < 0) {
278 dev_err(parent, "unable to register control minors\n");
279 goto __error;
280 }
281 err = snd_info_card_create(card);
282 if (err < 0) {
283 dev_err(parent, "unable to create card info\n");
284 goto __error_ctl;
285 }
286 *card_ret = card;
287 return 0;
288
289 __error_ctl:
290 snd_device_free_all(card);
291 __error:
292 put_device(&card->card_dev);
293 return err;
294}
295EXPORT_SYMBOL(snd_card_new);
296
297/* return non-zero if a card is already locked */
298int snd_card_locked(int card)
299{
300 int locked;
301
302 mutex_lock(&snd_card_mutex);
303 locked = test_bit(card, snd_cards_lock);
304 mutex_unlock(&snd_card_mutex);
305 return locked;
306}
307
308static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
309{
310 return -ENODEV;
311}
312
313static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
314 size_t count, loff_t *offset)
315{
316 return -ENODEV;
317}
318
319static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
320 size_t count, loff_t *offset)
321{
322 return -ENODEV;
323}
324
325static int snd_disconnect_release(struct inode *inode, struct file *file)
326{
327 struct snd_monitor_file *df = NULL, *_df;
328
329 spin_lock(&shutdown_lock);
330 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
331 if (_df->file == file) {
332 df = _df;
333 list_del_init(&df->shutdown_list);
334 break;
335 }
336 }
337 spin_unlock(&shutdown_lock);
338
339 if (likely(df)) {
340 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
341 df->disconnected_f_op->fasync(-1, file, 0);
342 return df->disconnected_f_op->release(inode, file);
343 }
344
345 panic("%s(%p, %p) failed!", __func__, inode, file);
346}
347
348static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
349{
350 return POLLERR | POLLNVAL;
351}
352
353static long snd_disconnect_ioctl(struct file *file,
354 unsigned int cmd, unsigned long arg)
355{
356 return -ENODEV;
357}
358
359static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
360{
361 return -ENODEV;
362}
363
364static int snd_disconnect_fasync(int fd, struct file *file, int on)
365{
366 return -ENODEV;
367}
368
369static const struct file_operations snd_shutdown_f_ops =
370{
371 .owner = THIS_MODULE,
372 .llseek = snd_disconnect_llseek,
373 .read = snd_disconnect_read,
374 .write = snd_disconnect_write,
375 .release = snd_disconnect_release,
376 .poll = snd_disconnect_poll,
377 .unlocked_ioctl = snd_disconnect_ioctl,
378#ifdef CONFIG_COMPAT
379 .compat_ioctl = snd_disconnect_ioctl,
380#endif
381 .mmap = snd_disconnect_mmap,
382 .fasync = snd_disconnect_fasync
383};
384
385/**
386 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
387 * @card: soundcard structure
388 *
389 * Disconnects all APIs from the file-operations (user space).
390 *
391 * Return: Zero, otherwise a negative error code.
392 *
393 * Note: The current implementation replaces all active file->f_op with special
394 * dummy file operations (they do nothing except release).
395 */
396int snd_card_disconnect(struct snd_card *card)
397{
398 struct snd_monitor_file *mfile;
399
400 if (!card)
401 return -EINVAL;
402
403 spin_lock(&card->files_lock);
404 if (card->shutdown) {
405 spin_unlock(&card->files_lock);
406 return 0;
407 }
408 card->shutdown = 1;
409 spin_unlock(&card->files_lock);
410
411 /* phase 1: disable fops (user space) operations for ALSA API */
412 mutex_lock(&snd_card_mutex);
413 snd_cards[card->number] = NULL;
414 clear_bit(card->number, snd_cards_lock);
415 mutex_unlock(&snd_card_mutex);
416
417 /* phase 2: replace file->f_op with special dummy operations */
418
419 spin_lock(&card->files_lock);
420 list_for_each_entry(mfile, &card->files_list, list) {
421 /* it's critical part, use endless loop */
422 /* we have no room to fail */
423 mfile->disconnected_f_op = mfile->file->f_op;
424
425 spin_lock(&shutdown_lock);
426 list_add(&mfile->shutdown_list, &shutdown_files);
427 spin_unlock(&shutdown_lock);
428
429 mfile->file->f_op = &snd_shutdown_f_ops;
430 fops_get(mfile->file->f_op);
431 }
432 spin_unlock(&card->files_lock);
433
434 /* phase 3: notify all connected devices about disconnection */
435 /* at this point, they cannot respond to any calls except release() */
436
437#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
438 if (snd_mixer_oss_notify_callback)
439 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
440#endif
441
442 /* notify all devices that we are disconnected */
443 snd_device_disconnect_all(card);
444
445 snd_info_card_disconnect(card);
446 if (card->registered) {
447 device_del(&card->card_dev);
448 card->registered = false;
449 }
450#ifdef CONFIG_PM
451 wake_up(&card->power_sleep);
452#endif
453 return 0;
454}
455
456EXPORT_SYMBOL(snd_card_disconnect);
457
458static int snd_card_do_free(struct snd_card *card)
459{
460#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
461 if (snd_mixer_oss_notify_callback)
462 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
463#endif
464 snd_device_free_all(card);
465 if (card->private_free)
466 card->private_free(card);
467 snd_info_free_entry(card->proc_id);
468 if (snd_info_card_free(card) < 0) {
469 dev_warn(card->dev, "unable to free card info\n");
470 /* Not fatal error */
471 }
472 if (card->release_completion)
473 complete(card->release_completion);
474 kfree(card);
475 return 0;
476}
477
478/**
479 * snd_card_free_when_closed - Disconnect the card, free it later eventually
480 * @card: soundcard structure
481 *
482 * Unlike snd_card_free(), this function doesn't try to release the card
483 * resource immediately, but tries to disconnect at first. When the card
484 * is still in use, the function returns before freeing the resources.
485 * The card resources will be freed when the refcount gets to zero.
486 */
487int snd_card_free_when_closed(struct snd_card *card)
488{
489 int ret = snd_card_disconnect(card);
490 if (ret)
491 return ret;
492 put_device(&card->card_dev);
493 return 0;
494}
495EXPORT_SYMBOL(snd_card_free_when_closed);
496
497/**
498 * snd_card_free - frees given soundcard structure
499 * @card: soundcard structure
500 *
501 * This function releases the soundcard structure and the all assigned
502 * devices automatically. That is, you don't have to release the devices
503 * by yourself.
504 *
505 * This function waits until the all resources are properly released.
506 *
507 * Return: Zero. Frees all associated devices and frees the control
508 * interface associated to given soundcard.
509 */
510int snd_card_free(struct snd_card *card)
511{
512 struct completion released;
513 int ret;
514
515 init_completion(&released);
516 card->release_completion = &released;
517 ret = snd_card_free_when_closed(card);
518 if (ret)
519 return ret;
520 /* wait, until all devices are ready for the free operation */
521 wait_for_completion(&released);
522 return 0;
523}
524EXPORT_SYMBOL(snd_card_free);
525
526/* retrieve the last word of shortname or longname */
527static const char *retrieve_id_from_card_name(const char *name)
528{
529 const char *spos = name;
530
531 while (*name) {
532 if (isspace(*name) && isalnum(name[1]))
533 spos = name + 1;
534 name++;
535 }
536 return spos;
537}
538
539/* return true if the given id string doesn't conflict any other card ids */
540static bool card_id_ok(struct snd_card *card, const char *id)
541{
542 int i;
543 if (!snd_info_check_reserved_words(id))
544 return false;
545 for (i = 0; i < snd_ecards_limit; i++) {
546 if (snd_cards[i] && snd_cards[i] != card &&
547 !strcmp(snd_cards[i]->id, id))
548 return false;
549 }
550 return true;
551}
552
553/* copy to card->id only with valid letters from nid */
554static void copy_valid_id_string(struct snd_card *card, const char *src,
555 const char *nid)
556{
557 char *id = card->id;
558
559 while (*nid && !isalnum(*nid))
560 nid++;
561 if (isdigit(*nid))
562 *id++ = isalpha(*src) ? *src : 'D';
563 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
564 if (isalnum(*nid))
565 *id++ = *nid;
566 nid++;
567 }
568 *id = 0;
569}
570
571/* Set card->id from the given string
572 * If the string conflicts with other ids, add a suffix to make it unique.
573 */
574static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
575 const char *nid)
576{
577 int len, loops;
578 bool is_default = false;
579 char *id;
580
581 copy_valid_id_string(card, src, nid);
582 id = card->id;
583
584 again:
585 /* use "Default" for obviously invalid strings
586 * ("card" conflicts with proc directories)
587 */
588 if (!*id || !strncmp(id, "card", 4)) {
589 strcpy(id, "Default");
590 is_default = true;
591 }
592
593 len = strlen(id);
594 for (loops = 0; loops < SNDRV_CARDS; loops++) {
595 char *spos;
596 char sfxstr[5]; /* "_012" */
597 int sfxlen;
598
599 if (card_id_ok(card, id))
600 return; /* OK */
601
602 /* Add _XYZ suffix */
603 sprintf(sfxstr, "_%X", loops + 1);
604 sfxlen = strlen(sfxstr);
605 if (len + sfxlen >= sizeof(card->id))
606 spos = id + sizeof(card->id) - sfxlen - 1;
607 else
608 spos = id + len;
609 strcpy(spos, sfxstr);
610 }
611 /* fallback to the default id */
612 if (!is_default) {
613 *id = 0;
614 goto again;
615 }
616 /* last resort... */
617 dev_err(card->dev, "unable to set card id (%s)\n", id);
618 if (card->proc_root->name)
619 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
620}
621
622/**
623 * snd_card_set_id - set card identification name
624 * @card: soundcard structure
625 * @nid: new identification string
626 *
627 * This function sets the card identification and checks for name
628 * collisions.
629 */
630void snd_card_set_id(struct snd_card *card, const char *nid)
631{
632 /* check if user specified own card->id */
633 if (card->id[0] != '\0')
634 return;
635 mutex_lock(&snd_card_mutex);
636 snd_card_set_id_no_lock(card, nid, nid);
637 mutex_unlock(&snd_card_mutex);
638}
639EXPORT_SYMBOL(snd_card_set_id);
640
641static ssize_t
642card_id_show_attr(struct device *dev,
643 struct device_attribute *attr, char *buf)
644{
645 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
646 return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
647}
648
649static ssize_t
650card_id_store_attr(struct device *dev, struct device_attribute *attr,
651 const char *buf, size_t count)
652{
653 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
654 char buf1[sizeof(card->id)];
655 size_t copy = count > sizeof(card->id) - 1 ?
656 sizeof(card->id) - 1 : count;
657 size_t idx;
658 int c;
659
660 for (idx = 0; idx < copy; idx++) {
661 c = buf[idx];
662 if (!isalnum(c) && c != '_' && c != '-')
663 return -EINVAL;
664 }
665 memcpy(buf1, buf, copy);
666 buf1[copy] = '\0';
667 mutex_lock(&snd_card_mutex);
668 if (!card_id_ok(NULL, buf1)) {
669 mutex_unlock(&snd_card_mutex);
670 return -EEXIST;
671 }
672 strcpy(card->id, buf1);
673 snd_info_card_id_change(card);
674 mutex_unlock(&snd_card_mutex);
675
676 return count;
677}
678
679static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
680
681static ssize_t
682card_number_show_attr(struct device *dev,
683 struct device_attribute *attr, char *buf)
684{
685 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
686 return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
687}
688
689static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
690
691static struct attribute *card_dev_attrs[] = {
692 &dev_attr_id.attr,
693 &dev_attr_number.attr,
694 NULL
695};
696
697static const struct attribute_group card_dev_attr_group = {
698 .attrs = card_dev_attrs,
699};
700
701/**
702 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
703 * @card: card instance
704 * @group: attribute group to append
705 */
706int snd_card_add_dev_attr(struct snd_card *card,
707 const struct attribute_group *group)
708{
709 int i;
710
711 /* loop for (arraysize-1) here to keep NULL at the last entry */
712 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
713 if (!card->dev_groups[i]) {
714 card->dev_groups[i] = group;
715 return 0;
716 }
717 }
718
719 dev_err(card->dev, "Too many groups assigned\n");
720 return -ENOSPC;
721};
722EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
723
724/**
725 * snd_card_register - register the soundcard
726 * @card: soundcard structure
727 *
728 * This function registers all the devices assigned to the soundcard.
729 * Until calling this, the ALSA control interface is blocked from the
730 * external accesses. Thus, you should call this function at the end
731 * of the initialization of the card.
732 *
733 * Return: Zero otherwise a negative error code if the registration failed.
734 */
735int snd_card_register(struct snd_card *card)
736{
737 int err;
738
739 if (snd_BUG_ON(!card))
740 return -EINVAL;
741
742 if (!card->registered) {
743 err = device_add(&card->card_dev);
744 if (err < 0)
745 return err;
746 card->registered = true;
747 }
748
749 if ((err = snd_device_register_all(card)) < 0)
750 return err;
751 mutex_lock(&snd_card_mutex);
752 if (snd_cards[card->number]) {
753 /* already registered */
754 mutex_unlock(&snd_card_mutex);
755 return snd_info_card_register(card); /* register pending info */
756 }
757 if (*card->id) {
758 /* make a unique id name from the given string */
759 char tmpid[sizeof(card->id)];
760 memcpy(tmpid, card->id, sizeof(card->id));
761 snd_card_set_id_no_lock(card, tmpid, tmpid);
762 } else {
763 /* create an id from either shortname or longname */
764 const char *src;
765 src = *card->shortname ? card->shortname : card->longname;
766 snd_card_set_id_no_lock(card, src,
767 retrieve_id_from_card_name(src));
768 }
769 snd_cards[card->number] = card;
770 mutex_unlock(&snd_card_mutex);
771 init_info_for_card(card);
772#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
773 if (snd_mixer_oss_notify_callback)
774 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
775#endif
776 return 0;
777}
778
779EXPORT_SYMBOL(snd_card_register);
780
781#ifdef CONFIG_SND_PROC_FS
782static void snd_card_info_read(struct snd_info_entry *entry,
783 struct snd_info_buffer *buffer)
784{
785 int idx, count;
786 struct snd_card *card;
787
788 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
789 mutex_lock(&snd_card_mutex);
790 if ((card = snd_cards[idx]) != NULL) {
791 count++;
792 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
793 idx,
794 card->id,
795 card->driver,
796 card->shortname);
797 snd_iprintf(buffer, " %s\n",
798 card->longname);
799 }
800 mutex_unlock(&snd_card_mutex);
801 }
802 if (!count)
803 snd_iprintf(buffer, "--- no soundcards ---\n");
804}
805
806#ifdef CONFIG_SND_OSSEMUL
807void snd_card_info_read_oss(struct snd_info_buffer *buffer)
808{
809 int idx, count;
810 struct snd_card *card;
811
812 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
813 mutex_lock(&snd_card_mutex);
814 if ((card = snd_cards[idx]) != NULL) {
815 count++;
816 snd_iprintf(buffer, "%s\n", card->longname);
817 }
818 mutex_unlock(&snd_card_mutex);
819 }
820 if (!count) {
821 snd_iprintf(buffer, "--- no soundcards ---\n");
822 }
823}
824
825#endif
826
827#ifdef MODULE
828static void snd_card_module_info_read(struct snd_info_entry *entry,
829 struct snd_info_buffer *buffer)
830{
831 int idx;
832 struct snd_card *card;
833
834 for (idx = 0; idx < SNDRV_CARDS; idx++) {
835 mutex_lock(&snd_card_mutex);
836 if ((card = snd_cards[idx]) != NULL)
837 snd_iprintf(buffer, "%2i %s\n",
838 idx, card->module->name);
839 mutex_unlock(&snd_card_mutex);
840 }
841}
842#endif
843
844int __init snd_card_info_init(void)
845{
846 struct snd_info_entry *entry;
847
848 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
849 if (! entry)
850 return -ENOMEM;
851 entry->c.text.read = snd_card_info_read;
852 if (snd_info_register(entry) < 0)
853 return -ENOMEM; /* freed in error path */
854
855#ifdef MODULE
856 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
857 if (!entry)
858 return -ENOMEM;
859 entry->c.text.read = snd_card_module_info_read;
860 if (snd_info_register(entry) < 0)
861 return -ENOMEM; /* freed in error path */
862#endif
863
864 return 0;
865}
866#endif /* CONFIG_SND_PROC_FS */
867
868/**
869 * snd_component_add - add a component string
870 * @card: soundcard structure
871 * @component: the component id string
872 *
873 * This function adds the component id string to the supported list.
874 * The component can be referred from the alsa-lib.
875 *
876 * Return: Zero otherwise a negative error code.
877 */
878
879int snd_component_add(struct snd_card *card, const char *component)
880{
881 char *ptr;
882 int len = strlen(component);
883
884 ptr = strstr(card->components, component);
885 if (ptr != NULL) {
886 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
887 return 1;
888 }
889 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
890 snd_BUG();
891 return -ENOMEM;
892 }
893 if (card->components[0] != '\0')
894 strcat(card->components, " ");
895 strcat(card->components, component);
896 return 0;
897}
898
899EXPORT_SYMBOL(snd_component_add);
900
901/**
902 * snd_card_file_add - add the file to the file list of the card
903 * @card: soundcard structure
904 * @file: file pointer
905 *
906 * This function adds the file to the file linked-list of the card.
907 * This linked-list is used to keep tracking the connection state,
908 * and to avoid the release of busy resources by hotplug.
909 *
910 * Return: zero or a negative error code.
911 */
912int snd_card_file_add(struct snd_card *card, struct file *file)
913{
914 struct snd_monitor_file *mfile;
915
916 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
917 if (mfile == NULL)
918 return -ENOMEM;
919 mfile->file = file;
920 mfile->disconnected_f_op = NULL;
921 INIT_LIST_HEAD(&mfile->shutdown_list);
922 spin_lock(&card->files_lock);
923 if (card->shutdown) {
924 spin_unlock(&card->files_lock);
925 kfree(mfile);
926 return -ENODEV;
927 }
928 list_add(&mfile->list, &card->files_list);
929 get_device(&card->card_dev);
930 spin_unlock(&card->files_lock);
931 return 0;
932}
933
934EXPORT_SYMBOL(snd_card_file_add);
935
936/**
937 * snd_card_file_remove - remove the file from the file list
938 * @card: soundcard structure
939 * @file: file pointer
940 *
941 * This function removes the file formerly added to the card via
942 * snd_card_file_add() function.
943 * If all files are removed and snd_card_free_when_closed() was
944 * called beforehand, it processes the pending release of
945 * resources.
946 *
947 * Return: Zero or a negative error code.
948 */
949int snd_card_file_remove(struct snd_card *card, struct file *file)
950{
951 struct snd_monitor_file *mfile, *found = NULL;
952
953 spin_lock(&card->files_lock);
954 list_for_each_entry(mfile, &card->files_list, list) {
955 if (mfile->file == file) {
956 list_del(&mfile->list);
957 spin_lock(&shutdown_lock);
958 list_del(&mfile->shutdown_list);
959 spin_unlock(&shutdown_lock);
960 if (mfile->disconnected_f_op)
961 fops_put(mfile->disconnected_f_op);
962 found = mfile;
963 break;
964 }
965 }
966 spin_unlock(&card->files_lock);
967 if (!found) {
968 dev_err(card->dev, "card file remove problem (%p)\n", file);
969 return -ENOENT;
970 }
971 kfree(found);
972 put_device(&card->card_dev);
973 return 0;
974}
975
976EXPORT_SYMBOL(snd_card_file_remove);
977
978#ifdef CONFIG_PM
979/**
980 * snd_power_wait - wait until the power-state is changed.
981 * @card: soundcard structure
982 * @power_state: expected power state
983 *
984 * Waits until the power-state is changed.
985 *
986 * Return: Zero if successful, or a negative error code.
987 *
988 * Note: the power lock must be active before call.
989 */
990int snd_power_wait(struct snd_card *card, unsigned int power_state)
991{
992 wait_queue_t wait;
993 int result = 0;
994
995 /* fastpath */
996 if (snd_power_get_state(card) == power_state)
997 return 0;
998 init_waitqueue_entry(&wait, current);
999 add_wait_queue(&card->power_sleep, &wait);
1000 while (1) {
1001 if (card->shutdown) {
1002 result = -ENODEV;
1003 break;
1004 }
1005 if (snd_power_get_state(card) == power_state)
1006 break;
1007 set_current_state(TASK_UNINTERRUPTIBLE);
1008 snd_power_unlock(card);
1009 schedule_timeout(30 * HZ);
1010 snd_power_lock(card);
1011 }
1012 remove_wait_queue(&card->power_sleep, &wait);
1013 return result;
1014}
1015
1016EXPORT_SYMBOL(snd_power_wait);
1017#endif /* CONFIG_PM */
1/*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/init.h>
23#include <linux/sched.h>
24#include <linux/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_SND_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 int init_info_for_card(struct snd_card *card)
111{
112 struct snd_info_entry *entry;
113
114 entry = snd_info_create_card_entry(card, "id", card->proc_root);
115 if (!entry) {
116 dev_dbg(card->dev, "unable to create card entry\n");
117 return -ENOMEM;
118 }
119 entry->c.text.read = snd_card_id_read;
120 card->proc_id = entry;
121
122 return snd_info_card_register(card);
123}
124#else /* !CONFIG_SND_PROC_FS */
125#define init_info_for_card(card)
126#endif
127
128static int check_empty_slot(struct module *module, int slot)
129{
130 return !slots[slot] || !*slots[slot];
131}
132
133/* return an empty slot number (>= 0) found in the given bitmask @mask.
134 * @mask == -1 == 0xffffffff means: take any free slot up to 32
135 * when no slot is available, return the original @mask as is.
136 */
137static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
138 struct module *module)
139{
140 int slot;
141
142 for (slot = 0; slot < SNDRV_CARDS; slot++) {
143 if (slot < 32 && !(mask & (1U << slot)))
144 continue;
145 if (!test_bit(slot, snd_cards_lock)) {
146 if (check(module, slot))
147 return slot; /* found */
148 }
149 }
150 return mask; /* unchanged */
151}
152
153/* the default release callback set in snd_device_initialize() below;
154 * this is just NOP for now, as almost all jobs are already done in
155 * dev_free callback of snd_device chain instead.
156 */
157static void default_release(struct device *dev)
158{
159}
160
161/**
162 * snd_device_initialize - Initialize struct device for sound devices
163 * @dev: device to initialize
164 * @card: card to assign, optional
165 */
166void snd_device_initialize(struct device *dev, struct snd_card *card)
167{
168 device_initialize(dev);
169 if (card)
170 dev->parent = &card->card_dev;
171 dev->class = sound_class;
172 dev->release = default_release;
173}
174EXPORT_SYMBOL_GPL(snd_device_initialize);
175
176static int snd_card_do_free(struct snd_card *card);
177static const struct attribute_group card_dev_attr_group;
178
179static void release_card_device(struct device *dev)
180{
181 snd_card_do_free(dev_to_snd_card(dev));
182}
183
184/**
185 * snd_card_new - create and initialize a soundcard structure
186 * @parent: the parent device object
187 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
188 * @xid: card identification (ASCII string)
189 * @module: top level module for locking
190 * @extra_size: allocate this extra size after the main soundcard structure
191 * @card_ret: the pointer to store the created card instance
192 *
193 * Creates and initializes a soundcard structure.
194 *
195 * The function allocates snd_card instance via kzalloc with the given
196 * space for the driver to use freely. The allocated struct is stored
197 * in the given card_ret pointer.
198 *
199 * Return: Zero if successful or a negative error code.
200 */
201int snd_card_new(struct device *parent, int idx, const char *xid,
202 struct module *module, int extra_size,
203 struct snd_card **card_ret)
204{
205 struct snd_card *card;
206 int err;
207
208 if (snd_BUG_ON(!card_ret))
209 return -EINVAL;
210 *card_ret = NULL;
211
212 if (extra_size < 0)
213 extra_size = 0;
214 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
215 if (!card)
216 return -ENOMEM;
217 if (extra_size > 0)
218 card->private_data = (char *)card + sizeof(struct snd_card);
219 if (xid)
220 strlcpy(card->id, xid, sizeof(card->id));
221 err = 0;
222 mutex_lock(&snd_card_mutex);
223 if (idx < 0) /* first check the matching module-name slot */
224 idx = get_slot_from_bitmask(idx, module_slot_match, module);
225 if (idx < 0) /* if not matched, assign an empty slot */
226 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
227 if (idx < 0)
228 err = -ENODEV;
229 else if (idx < snd_ecards_limit) {
230 if (test_bit(idx, snd_cards_lock))
231 err = -EBUSY; /* invalid */
232 } else if (idx >= SNDRV_CARDS)
233 err = -ENODEV;
234 if (err < 0) {
235 mutex_unlock(&snd_card_mutex);
236 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
237 idx, snd_ecards_limit - 1, err);
238 kfree(card);
239 return err;
240 }
241 set_bit(idx, snd_cards_lock); /* lock it */
242 if (idx >= snd_ecards_limit)
243 snd_ecards_limit = idx + 1; /* increase the limit */
244 mutex_unlock(&snd_card_mutex);
245 card->dev = parent;
246 card->number = idx;
247 card->module = module;
248 INIT_LIST_HEAD(&card->devices);
249 init_rwsem(&card->controls_rwsem);
250 rwlock_init(&card->ctl_files_rwlock);
251 INIT_LIST_HEAD(&card->controls);
252 INIT_LIST_HEAD(&card->ctl_files);
253 spin_lock_init(&card->files_lock);
254 INIT_LIST_HEAD(&card->files_list);
255#ifdef CONFIG_PM
256 init_waitqueue_head(&card->power_sleep);
257#endif
258 init_waitqueue_head(&card->remove_sleep);
259
260 device_initialize(&card->card_dev);
261 card->card_dev.parent = parent;
262 card->card_dev.class = sound_class;
263 card->card_dev.release = release_card_device;
264 card->card_dev.groups = card->dev_groups;
265 card->dev_groups[0] = &card_dev_attr_group;
266 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
267 if (err < 0)
268 goto __error;
269
270 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
271 dev_driver_string(card->dev), dev_name(&card->card_dev));
272
273 /* the control interface cannot be accessed from the user space until */
274 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
275 err = snd_ctl_create(card);
276 if (err < 0) {
277 dev_err(parent, "unable to register control minors\n");
278 goto __error;
279 }
280 err = snd_info_card_create(card);
281 if (err < 0) {
282 dev_err(parent, "unable to create card info\n");
283 goto __error_ctl;
284 }
285 *card_ret = card;
286 return 0;
287
288 __error_ctl:
289 snd_device_free_all(card);
290 __error:
291 put_device(&card->card_dev);
292 return err;
293}
294EXPORT_SYMBOL(snd_card_new);
295
296/* return non-zero if a card is already locked */
297int snd_card_locked(int card)
298{
299 int locked;
300
301 mutex_lock(&snd_card_mutex);
302 locked = test_bit(card, snd_cards_lock);
303 mutex_unlock(&snd_card_mutex);
304 return locked;
305}
306
307static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
308{
309 return -ENODEV;
310}
311
312static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
313 size_t count, loff_t *offset)
314{
315 return -ENODEV;
316}
317
318static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
319 size_t count, loff_t *offset)
320{
321 return -ENODEV;
322}
323
324static int snd_disconnect_release(struct inode *inode, struct file *file)
325{
326 struct snd_monitor_file *df = NULL, *_df;
327
328 spin_lock(&shutdown_lock);
329 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
330 if (_df->file == file) {
331 df = _df;
332 list_del_init(&df->shutdown_list);
333 break;
334 }
335 }
336 spin_unlock(&shutdown_lock);
337
338 if (likely(df)) {
339 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
340 df->disconnected_f_op->fasync(-1, file, 0);
341 return df->disconnected_f_op->release(inode, file);
342 }
343
344 panic("%s(%p, %p) failed!", __func__, inode, file);
345}
346
347static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
348{
349 return EPOLLERR | EPOLLNVAL;
350}
351
352static long snd_disconnect_ioctl(struct file *file,
353 unsigned int cmd, unsigned long arg)
354{
355 return -ENODEV;
356}
357
358static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
359{
360 return -ENODEV;
361}
362
363static int snd_disconnect_fasync(int fd, struct file *file, int on)
364{
365 return -ENODEV;
366}
367
368static const struct file_operations snd_shutdown_f_ops =
369{
370 .owner = THIS_MODULE,
371 .llseek = snd_disconnect_llseek,
372 .read = snd_disconnect_read,
373 .write = snd_disconnect_write,
374 .release = snd_disconnect_release,
375 .poll = snd_disconnect_poll,
376 .unlocked_ioctl = snd_disconnect_ioctl,
377#ifdef CONFIG_COMPAT
378 .compat_ioctl = snd_disconnect_ioctl,
379#endif
380 .mmap = snd_disconnect_mmap,
381 .fasync = snd_disconnect_fasync
382};
383
384/**
385 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
386 * @card: soundcard structure
387 *
388 * Disconnects all APIs from the file-operations (user space).
389 *
390 * Return: Zero, otherwise a negative error code.
391 *
392 * Note: The current implementation replaces all active file->f_op with special
393 * dummy file operations (they do nothing except release).
394 */
395int snd_card_disconnect(struct snd_card *card)
396{
397 struct snd_monitor_file *mfile;
398
399 if (!card)
400 return -EINVAL;
401
402 spin_lock(&card->files_lock);
403 if (card->shutdown) {
404 spin_unlock(&card->files_lock);
405 return 0;
406 }
407 card->shutdown = 1;
408 spin_unlock(&card->files_lock);
409
410 /* phase 1: disable fops (user space) operations for ALSA API */
411 mutex_lock(&snd_card_mutex);
412 snd_cards[card->number] = NULL;
413 clear_bit(card->number, snd_cards_lock);
414 mutex_unlock(&snd_card_mutex);
415
416 /* phase 2: replace file->f_op with special dummy operations */
417
418 spin_lock(&card->files_lock);
419 list_for_each_entry(mfile, &card->files_list, list) {
420 /* it's critical part, use endless loop */
421 /* we have no room to fail */
422 mfile->disconnected_f_op = mfile->file->f_op;
423
424 spin_lock(&shutdown_lock);
425 list_add(&mfile->shutdown_list, &shutdown_files);
426 spin_unlock(&shutdown_lock);
427
428 mfile->file->f_op = &snd_shutdown_f_ops;
429 fops_get(mfile->file->f_op);
430 }
431 spin_unlock(&card->files_lock);
432
433 /* phase 3: notify all connected devices about disconnection */
434 /* at this point, they cannot respond to any calls except release() */
435
436#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
437 if (snd_mixer_oss_notify_callback)
438 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
439#endif
440
441 /* notify all devices that we are disconnected */
442 snd_device_disconnect_all(card);
443
444 snd_info_card_disconnect(card);
445 if (card->registered) {
446 device_del(&card->card_dev);
447 card->registered = false;
448 }
449#ifdef CONFIG_PM
450 wake_up(&card->power_sleep);
451#endif
452 return 0;
453}
454EXPORT_SYMBOL(snd_card_disconnect);
455
456/**
457 * snd_card_disconnect_sync - disconnect card and wait until files get closed
458 * @card: card object to disconnect
459 *
460 * This calls snd_card_disconnect() for disconnecting all belonging components
461 * and waits until all pending files get closed.
462 * It assures that all accesses from user-space finished so that the driver
463 * can release its resources gracefully.
464 */
465void snd_card_disconnect_sync(struct snd_card *card)
466{
467 int err;
468
469 err = snd_card_disconnect(card);
470 if (err < 0) {
471 dev_err(card->dev,
472 "snd_card_disconnect error (%d), skipping sync\n",
473 err);
474 return;
475 }
476
477 spin_lock_irq(&card->files_lock);
478 wait_event_lock_irq(card->remove_sleep,
479 list_empty(&card->files_list),
480 card->files_lock);
481 spin_unlock_irq(&card->files_lock);
482}
483EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
484
485static int snd_card_do_free(struct snd_card *card)
486{
487#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
488 if (snd_mixer_oss_notify_callback)
489 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
490#endif
491 snd_device_free_all(card);
492 if (card->private_free)
493 card->private_free(card);
494 snd_info_free_entry(card->proc_id);
495 if (snd_info_card_free(card) < 0) {
496 dev_warn(card->dev, "unable to free card info\n");
497 /* Not fatal error */
498 }
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 struct completion released;
540 int ret;
541
542 init_completion(&released);
543 card->release_completion = &released;
544 ret = snd_card_free_when_closed(card);
545 if (ret)
546 return ret;
547 /* wait, until all devices are ready for the free operation */
548 wait_for_completion(&released);
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 strlcpy(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
669card_id_show_attr(struct device *dev,
670 struct device_attribute *attr, char *buf)
671{
672 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
673 return scnprintf(buf, PAGE_SIZE, "%s\n", card->id);
674}
675
676static ssize_t
677card_id_store_attr(struct device *dev, struct device_attribute *attr,
678 const char *buf, size_t count)
679{
680 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
681 char buf1[sizeof(card->id)];
682 size_t copy = count > sizeof(card->id) - 1 ?
683 sizeof(card->id) - 1 : count;
684 size_t idx;
685 int c;
686
687 for (idx = 0; idx < copy; idx++) {
688 c = buf[idx];
689 if (!isalnum(c) && c != '_' && c != '-')
690 return -EINVAL;
691 }
692 memcpy(buf1, buf, copy);
693 buf1[copy] = '\0';
694 mutex_lock(&snd_card_mutex);
695 if (!card_id_ok(NULL, buf1)) {
696 mutex_unlock(&snd_card_mutex);
697 return -EEXIST;
698 }
699 strcpy(card->id, buf1);
700 snd_info_card_id_change(card);
701 mutex_unlock(&snd_card_mutex);
702
703 return count;
704}
705
706static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
707
708static ssize_t
709card_number_show_attr(struct device *dev,
710 struct device_attribute *attr, char *buf)
711{
712 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
713 return scnprintf(buf, PAGE_SIZE, "%i\n", card->number);
714}
715
716static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
717
718static struct attribute *card_dev_attrs[] = {
719 &dev_attr_id.attr,
720 &dev_attr_number.attr,
721 NULL
722};
723
724static const struct attribute_group card_dev_attr_group = {
725 .attrs = card_dev_attrs,
726};
727
728/**
729 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
730 * @card: card instance
731 * @group: attribute group to append
732 */
733int snd_card_add_dev_attr(struct snd_card *card,
734 const struct attribute_group *group)
735{
736 int i;
737
738 /* loop for (arraysize-1) here to keep NULL at the last entry */
739 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
740 if (!card->dev_groups[i]) {
741 card->dev_groups[i] = group;
742 return 0;
743 }
744 }
745
746 dev_err(card->dev, "Too many groups assigned\n");
747 return -ENOSPC;
748}
749EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
750
751/**
752 * snd_card_register - register the soundcard
753 * @card: soundcard structure
754 *
755 * This function registers all the devices assigned to the soundcard.
756 * Until calling this, the ALSA control interface is blocked from the
757 * external accesses. Thus, you should call this function at the end
758 * of the initialization of the card.
759 *
760 * Return: Zero otherwise a negative error code if the registration failed.
761 */
762int snd_card_register(struct snd_card *card)
763{
764 int err;
765
766 if (snd_BUG_ON(!card))
767 return -EINVAL;
768
769 if (!card->registered) {
770 err = device_add(&card->card_dev);
771 if (err < 0)
772 return err;
773 card->registered = true;
774 }
775
776 if ((err = snd_device_register_all(card)) < 0)
777 return err;
778 mutex_lock(&snd_card_mutex);
779 if (snd_cards[card->number]) {
780 /* already registered */
781 mutex_unlock(&snd_card_mutex);
782 return snd_info_card_register(card); /* register pending info */
783 }
784 if (*card->id) {
785 /* make a unique id name from the given string */
786 char tmpid[sizeof(card->id)];
787 memcpy(tmpid, card->id, sizeof(card->id));
788 snd_card_set_id_no_lock(card, tmpid, tmpid);
789 } else {
790 /* create an id from either shortname or longname */
791 const char *src;
792 src = *card->shortname ? card->shortname : card->longname;
793 snd_card_set_id_no_lock(card, src,
794 retrieve_id_from_card_name(src));
795 }
796 snd_cards[card->number] = card;
797 mutex_unlock(&snd_card_mutex);
798 init_info_for_card(card);
799#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
800 if (snd_mixer_oss_notify_callback)
801 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
802#endif
803 return 0;
804}
805EXPORT_SYMBOL(snd_card_register);
806
807#ifdef CONFIG_SND_PROC_FS
808static void snd_card_info_read(struct snd_info_entry *entry,
809 struct snd_info_buffer *buffer)
810{
811 int idx, count;
812 struct snd_card *card;
813
814 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
815 mutex_lock(&snd_card_mutex);
816 if ((card = snd_cards[idx]) != NULL) {
817 count++;
818 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
819 idx,
820 card->id,
821 card->driver,
822 card->shortname);
823 snd_iprintf(buffer, " %s\n",
824 card->longname);
825 }
826 mutex_unlock(&snd_card_mutex);
827 }
828 if (!count)
829 snd_iprintf(buffer, "--- no soundcards ---\n");
830}
831
832#ifdef CONFIG_SND_OSSEMUL
833void snd_card_info_read_oss(struct snd_info_buffer *buffer)
834{
835 int idx, count;
836 struct snd_card *card;
837
838 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
839 mutex_lock(&snd_card_mutex);
840 if ((card = snd_cards[idx]) != NULL) {
841 count++;
842 snd_iprintf(buffer, "%s\n", card->longname);
843 }
844 mutex_unlock(&snd_card_mutex);
845 }
846 if (!count) {
847 snd_iprintf(buffer, "--- no soundcards ---\n");
848 }
849}
850
851#endif
852
853#ifdef MODULE
854static void snd_card_module_info_read(struct snd_info_entry *entry,
855 struct snd_info_buffer *buffer)
856{
857 int idx;
858 struct snd_card *card;
859
860 for (idx = 0; idx < SNDRV_CARDS; idx++) {
861 mutex_lock(&snd_card_mutex);
862 if ((card = snd_cards[idx]) != NULL)
863 snd_iprintf(buffer, "%2i %s\n",
864 idx, card->module->name);
865 mutex_unlock(&snd_card_mutex);
866 }
867}
868#endif
869
870int __init snd_card_info_init(void)
871{
872 struct snd_info_entry *entry;
873
874 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
875 if (! entry)
876 return -ENOMEM;
877 entry->c.text.read = snd_card_info_read;
878 if (snd_info_register(entry) < 0)
879 return -ENOMEM; /* freed in error path */
880
881#ifdef MODULE
882 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
883 if (!entry)
884 return -ENOMEM;
885 entry->c.text.read = snd_card_module_info_read;
886 if (snd_info_register(entry) < 0)
887 return -ENOMEM; /* freed in error path */
888#endif
889
890 return 0;
891}
892#endif /* CONFIG_SND_PROC_FS */
893
894/**
895 * snd_component_add - add a component string
896 * @card: soundcard structure
897 * @component: the component id string
898 *
899 * This function adds the component id string to the supported list.
900 * The component can be referred from the alsa-lib.
901 *
902 * Return: Zero otherwise a negative error code.
903 */
904
905int snd_component_add(struct snd_card *card, const char *component)
906{
907 char *ptr;
908 int len = strlen(component);
909
910 ptr = strstr(card->components, component);
911 if (ptr != NULL) {
912 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
913 return 1;
914 }
915 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
916 snd_BUG();
917 return -ENOMEM;
918 }
919 if (card->components[0] != '\0')
920 strcat(card->components, " ");
921 strcat(card->components, component);
922 return 0;
923}
924EXPORT_SYMBOL(snd_component_add);
925
926/**
927 * snd_card_file_add - add the file to the file list of the card
928 * @card: soundcard structure
929 * @file: file pointer
930 *
931 * This function adds the file to the file linked-list of the card.
932 * This linked-list is used to keep tracking the connection state,
933 * and to avoid the release of busy resources by hotplug.
934 *
935 * Return: zero or a negative error code.
936 */
937int snd_card_file_add(struct snd_card *card, struct file *file)
938{
939 struct snd_monitor_file *mfile;
940
941 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
942 if (mfile == NULL)
943 return -ENOMEM;
944 mfile->file = file;
945 mfile->disconnected_f_op = NULL;
946 INIT_LIST_HEAD(&mfile->shutdown_list);
947 spin_lock(&card->files_lock);
948 if (card->shutdown) {
949 spin_unlock(&card->files_lock);
950 kfree(mfile);
951 return -ENODEV;
952 }
953 list_add(&mfile->list, &card->files_list);
954 get_device(&card->card_dev);
955 spin_unlock(&card->files_lock);
956 return 0;
957}
958EXPORT_SYMBOL(snd_card_file_add);
959
960/**
961 * snd_card_file_remove - remove the file from the file list
962 * @card: soundcard structure
963 * @file: file pointer
964 *
965 * This function removes the file formerly added to the card via
966 * snd_card_file_add() function.
967 * If all files are removed and snd_card_free_when_closed() was
968 * called beforehand, it processes the pending release of
969 * resources.
970 *
971 * Return: Zero or a negative error code.
972 */
973int snd_card_file_remove(struct snd_card *card, struct file *file)
974{
975 struct snd_monitor_file *mfile, *found = NULL;
976
977 spin_lock(&card->files_lock);
978 list_for_each_entry(mfile, &card->files_list, list) {
979 if (mfile->file == file) {
980 list_del(&mfile->list);
981 spin_lock(&shutdown_lock);
982 list_del(&mfile->shutdown_list);
983 spin_unlock(&shutdown_lock);
984 if (mfile->disconnected_f_op)
985 fops_put(mfile->disconnected_f_op);
986 found = mfile;
987 break;
988 }
989 }
990 if (list_empty(&card->files_list))
991 wake_up_all(&card->remove_sleep);
992 spin_unlock(&card->files_lock);
993 if (!found) {
994 dev_err(card->dev, "card file remove problem (%p)\n", file);
995 return -ENOENT;
996 }
997 kfree(found);
998 put_device(&card->card_dev);
999 return 0;
1000}
1001EXPORT_SYMBOL(snd_card_file_remove);
1002
1003#ifdef CONFIG_PM
1004/**
1005 * snd_power_wait - wait until the power-state is changed.
1006 * @card: soundcard structure
1007 * @power_state: expected power state
1008 *
1009 * Waits until the power-state is changed.
1010 *
1011 * Return: Zero if successful, or a negative error code.
1012 */
1013int snd_power_wait(struct snd_card *card, unsigned int power_state)
1014{
1015 wait_queue_entry_t wait;
1016 int result = 0;
1017
1018 /* fastpath */
1019 if (snd_power_get_state(card) == power_state)
1020 return 0;
1021 init_waitqueue_entry(&wait, current);
1022 add_wait_queue(&card->power_sleep, &wait);
1023 while (1) {
1024 if (card->shutdown) {
1025 result = -ENODEV;
1026 break;
1027 }
1028 if (snd_power_get_state(card) == power_state)
1029 break;
1030 set_current_state(TASK_UNINTERRUPTIBLE);
1031 schedule_timeout(30 * HZ);
1032 }
1033 remove_wait_queue(&card->power_sleep, &wait);
1034 return result;
1035}
1036EXPORT_SYMBOL(snd_power_wait);
1037#endif /* CONFIG_PM */