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