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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Initialization routines
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/init.h>
8#include <linux/sched.h>
9#include <linux/module.h>
10#include <linux/device.h>
11#include <linux/file.h>
12#include <linux/slab.h>
13#include <linux/time.h>
14#include <linux/ctype.h>
15#include <linux/pm.h>
16#include <linux/completion.h>
17
18#include <sound/core.h>
19#include <sound/control.h>
20#include <sound/info.h>
21
22/* monitor files for graceful shutdown (hotplug) */
23struct snd_monitor_file {
24 struct file *file;
25 const struct file_operations *disconnected_f_op;
26 struct list_head shutdown_list; /* still need to shutdown */
27 struct list_head list; /* link of monitor files */
28};
29
30static DEFINE_SPINLOCK(shutdown_lock);
31static LIST_HEAD(shutdown_files);
32
33static const struct file_operations snd_shutdown_f_ops;
34
35/* locked for registering/using */
36static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
37static struct snd_card *snd_cards[SNDRV_CARDS];
38
39static DEFINE_MUTEX(snd_card_mutex);
40
41static char *slots[SNDRV_CARDS];
42module_param_array(slots, charp, NULL, 0444);
43MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
44
45/* return non-zero if the given index is reserved for the given
46 * module via slots option
47 */
48static int module_slot_match(struct module *module, int idx)
49{
50 int match = 1;
51#ifdef MODULE
52 const char *s1, *s2;
53
54 if (!module || !*module->name || !slots[idx])
55 return 0;
56
57 s1 = module->name;
58 s2 = slots[idx];
59 if (*s2 == '!') {
60 match = 0; /* negative match */
61 s2++;
62 }
63 /* compare module name strings
64 * hyphens are handled as equivalent with underscore
65 */
66 for (;;) {
67 char c1 = *s1++;
68 char c2 = *s2++;
69 if (c1 == '-')
70 c1 = '_';
71 if (c2 == '-')
72 c2 = '_';
73 if (c1 != c2)
74 return !match;
75 if (!c1)
76 break;
77 }
78#endif /* MODULE */
79 return match;
80}
81
82#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
83int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
84EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
85#endif
86
87static int check_empty_slot(struct module *module, int slot)
88{
89 return !slots[slot] || !*slots[slot];
90}
91
92/* return an empty slot number (>= 0) found in the given bitmask @mask.
93 * @mask == -1 == 0xffffffff means: take any free slot up to 32
94 * when no slot is available, return the original @mask as is.
95 */
96static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
97 struct module *module)
98{
99 int slot;
100
101 for (slot = 0; slot < SNDRV_CARDS; slot++) {
102 if (slot < 32 && !(mask & (1U << slot)))
103 continue;
104 if (!test_bit(slot, snd_cards_lock)) {
105 if (check(module, slot))
106 return slot; /* found */
107 }
108 }
109 return mask; /* unchanged */
110}
111
112/* the default release callback set in snd_device_initialize() below;
113 * this is just NOP for now, as almost all jobs are already done in
114 * dev_free callback of snd_device chain instead.
115 */
116static void default_release(struct device *dev)
117{
118}
119
120/**
121 * snd_device_initialize - Initialize struct device for sound devices
122 * @dev: device to initialize
123 * @card: card to assign, optional
124 */
125void snd_device_initialize(struct device *dev, struct snd_card *card)
126{
127 device_initialize(dev);
128 if (card)
129 dev->parent = &card->card_dev;
130 dev->class = sound_class;
131 dev->release = default_release;
132}
133EXPORT_SYMBOL_GPL(snd_device_initialize);
134
135static int snd_card_do_free(struct snd_card *card);
136static const struct attribute_group card_dev_attr_group;
137
138static void release_card_device(struct device *dev)
139{
140 snd_card_do_free(dev_to_snd_card(dev));
141}
142
143/**
144 * snd_card_new - create and initialize a soundcard structure
145 * @parent: the parent device object
146 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
147 * @xid: card identification (ASCII string)
148 * @module: top level module for locking
149 * @extra_size: allocate this extra size after the main soundcard structure
150 * @card_ret: the pointer to store the created card instance
151 *
152 * Creates and initializes a soundcard structure.
153 *
154 * The function allocates snd_card instance via kzalloc with the given
155 * space for the driver to use freely. The allocated struct is stored
156 * in the given card_ret pointer.
157 *
158 * Return: Zero if successful or a negative error code.
159 */
160int snd_card_new(struct device *parent, int idx, const char *xid,
161 struct module *module, int extra_size,
162 struct snd_card **card_ret)
163{
164 struct snd_card *card;
165 int err;
166
167 if (snd_BUG_ON(!card_ret))
168 return -EINVAL;
169 *card_ret = NULL;
170
171 if (extra_size < 0)
172 extra_size = 0;
173 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
174 if (!card)
175 return -ENOMEM;
176 if (extra_size > 0)
177 card->private_data = (char *)card + sizeof(struct snd_card);
178 if (xid)
179 strlcpy(card->id, xid, sizeof(card->id));
180 err = 0;
181 mutex_lock(&snd_card_mutex);
182 if (idx < 0) /* first check the matching module-name slot */
183 idx = get_slot_from_bitmask(idx, module_slot_match, module);
184 if (idx < 0) /* if not matched, assign an empty slot */
185 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
186 if (idx < 0)
187 err = -ENODEV;
188 else if (idx < snd_ecards_limit) {
189 if (test_bit(idx, snd_cards_lock))
190 err = -EBUSY; /* invalid */
191 } else if (idx >= SNDRV_CARDS)
192 err = -ENODEV;
193 if (err < 0) {
194 mutex_unlock(&snd_card_mutex);
195 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
196 idx, snd_ecards_limit - 1, err);
197 kfree(card);
198 return err;
199 }
200 set_bit(idx, snd_cards_lock); /* lock it */
201 if (idx >= snd_ecards_limit)
202 snd_ecards_limit = idx + 1; /* increase the limit */
203 mutex_unlock(&snd_card_mutex);
204 card->dev = parent;
205 card->number = idx;
206 card->module = module;
207 INIT_LIST_HEAD(&card->devices);
208 init_rwsem(&card->controls_rwsem);
209 rwlock_init(&card->ctl_files_rwlock);
210 INIT_LIST_HEAD(&card->controls);
211 INIT_LIST_HEAD(&card->ctl_files);
212 spin_lock_init(&card->files_lock);
213 INIT_LIST_HEAD(&card->files_list);
214#ifdef CONFIG_PM
215 init_waitqueue_head(&card->power_sleep);
216#endif
217 init_waitqueue_head(&card->remove_sleep);
218
219 device_initialize(&card->card_dev);
220 card->card_dev.parent = parent;
221 card->card_dev.class = sound_class;
222 card->card_dev.release = release_card_device;
223 card->card_dev.groups = card->dev_groups;
224 card->dev_groups[0] = &card_dev_attr_group;
225 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
226 if (err < 0)
227 goto __error;
228
229 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
230 dev_driver_string(card->dev), dev_name(&card->card_dev));
231
232 /* the control interface cannot be accessed from the user space until */
233 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
234 err = snd_ctl_create(card);
235 if (err < 0) {
236 dev_err(parent, "unable to register control minors\n");
237 goto __error;
238 }
239 err = snd_info_card_create(card);
240 if (err < 0) {
241 dev_err(parent, "unable to create card info\n");
242 goto __error_ctl;
243 }
244 *card_ret = card;
245 return 0;
246
247 __error_ctl:
248 snd_device_free_all(card);
249 __error:
250 put_device(&card->card_dev);
251 return err;
252}
253EXPORT_SYMBOL(snd_card_new);
254
255/**
256 * snd_card_ref - Get the card object from the index
257 * @idx: the card index
258 *
259 * Returns a card object corresponding to the given index or NULL if not found.
260 * Release the object via snd_card_unref().
261 */
262struct snd_card *snd_card_ref(int idx)
263{
264 struct snd_card *card;
265
266 mutex_lock(&snd_card_mutex);
267 card = snd_cards[idx];
268 if (card)
269 get_device(&card->card_dev);
270 mutex_unlock(&snd_card_mutex);
271 return card;
272}
273EXPORT_SYMBOL_GPL(snd_card_ref);
274
275/* return non-zero if a card is already locked */
276int snd_card_locked(int card)
277{
278 int locked;
279
280 mutex_lock(&snd_card_mutex);
281 locked = test_bit(card, snd_cards_lock);
282 mutex_unlock(&snd_card_mutex);
283 return locked;
284}
285
286static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
287{
288 return -ENODEV;
289}
290
291static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
292 size_t count, loff_t *offset)
293{
294 return -ENODEV;
295}
296
297static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
298 size_t count, loff_t *offset)
299{
300 return -ENODEV;
301}
302
303static int snd_disconnect_release(struct inode *inode, struct file *file)
304{
305 struct snd_monitor_file *df = NULL, *_df;
306
307 spin_lock(&shutdown_lock);
308 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
309 if (_df->file == file) {
310 df = _df;
311 list_del_init(&df->shutdown_list);
312 break;
313 }
314 }
315 spin_unlock(&shutdown_lock);
316
317 if (likely(df)) {
318 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
319 df->disconnected_f_op->fasync(-1, file, 0);
320 return df->disconnected_f_op->release(inode, file);
321 }
322
323 panic("%s(%p, %p) failed!", __func__, inode, file);
324}
325
326static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
327{
328 return EPOLLERR | EPOLLNVAL;
329}
330
331static long snd_disconnect_ioctl(struct file *file,
332 unsigned int cmd, unsigned long arg)
333{
334 return -ENODEV;
335}
336
337static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
338{
339 return -ENODEV;
340}
341
342static int snd_disconnect_fasync(int fd, struct file *file, int on)
343{
344 return -ENODEV;
345}
346
347static const struct file_operations snd_shutdown_f_ops =
348{
349 .owner = THIS_MODULE,
350 .llseek = snd_disconnect_llseek,
351 .read = snd_disconnect_read,
352 .write = snd_disconnect_write,
353 .release = snd_disconnect_release,
354 .poll = snd_disconnect_poll,
355 .unlocked_ioctl = snd_disconnect_ioctl,
356#ifdef CONFIG_COMPAT
357 .compat_ioctl = snd_disconnect_ioctl,
358#endif
359 .mmap = snd_disconnect_mmap,
360 .fasync = snd_disconnect_fasync
361};
362
363/**
364 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
365 * @card: soundcard structure
366 *
367 * Disconnects all APIs from the file-operations (user space).
368 *
369 * Return: Zero, otherwise a negative error code.
370 *
371 * Note: The current implementation replaces all active file->f_op with special
372 * dummy file operations (they do nothing except release).
373 */
374int snd_card_disconnect(struct snd_card *card)
375{
376 struct snd_monitor_file *mfile;
377
378 if (!card)
379 return -EINVAL;
380
381 spin_lock(&card->files_lock);
382 if (card->shutdown) {
383 spin_unlock(&card->files_lock);
384 return 0;
385 }
386 card->shutdown = 1;
387 spin_unlock(&card->files_lock);
388
389 /* replace file->f_op with special dummy operations */
390 spin_lock(&card->files_lock);
391 list_for_each_entry(mfile, &card->files_list, list) {
392 /* it's critical part, use endless loop */
393 /* we have no room to fail */
394 mfile->disconnected_f_op = mfile->file->f_op;
395
396 spin_lock(&shutdown_lock);
397 list_add(&mfile->shutdown_list, &shutdown_files);
398 spin_unlock(&shutdown_lock);
399
400 mfile->file->f_op = &snd_shutdown_f_ops;
401 fops_get(mfile->file->f_op);
402 }
403 spin_unlock(&card->files_lock);
404
405 /* notify all connected devices about disconnection */
406 /* at this point, they cannot respond to any calls except release() */
407
408#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
409 if (snd_mixer_oss_notify_callback)
410 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
411#endif
412
413 /* notify all devices that we are disconnected */
414 snd_device_disconnect_all(card);
415
416 snd_info_card_disconnect(card);
417 if (card->registered) {
418 device_del(&card->card_dev);
419 card->registered = false;
420 }
421
422 /* disable fops (user space) operations for ALSA API */
423 mutex_lock(&snd_card_mutex);
424 snd_cards[card->number] = NULL;
425 clear_bit(card->number, snd_cards_lock);
426 mutex_unlock(&snd_card_mutex);
427
428#ifdef CONFIG_PM
429 wake_up(&card->power_sleep);
430#endif
431 return 0;
432}
433EXPORT_SYMBOL(snd_card_disconnect);
434
435/**
436 * snd_card_disconnect_sync - disconnect card and wait until files get closed
437 * @card: card object to disconnect
438 *
439 * This calls snd_card_disconnect() for disconnecting all belonging components
440 * and waits until all pending files get closed.
441 * It assures that all accesses from user-space finished so that the driver
442 * can release its resources gracefully.
443 */
444void snd_card_disconnect_sync(struct snd_card *card)
445{
446 int err;
447
448 err = snd_card_disconnect(card);
449 if (err < 0) {
450 dev_err(card->dev,
451 "snd_card_disconnect error (%d), skipping sync\n",
452 err);
453 return;
454 }
455
456 spin_lock_irq(&card->files_lock);
457 wait_event_lock_irq(card->remove_sleep,
458 list_empty(&card->files_list),
459 card->files_lock);
460 spin_unlock_irq(&card->files_lock);
461}
462EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
463
464static int snd_card_do_free(struct snd_card *card)
465{
466#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
467 if (snd_mixer_oss_notify_callback)
468 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
469#endif
470 snd_device_free_all(card);
471 if (card->private_free)
472 card->private_free(card);
473 if (snd_info_card_free(card) < 0) {
474 dev_warn(card->dev, "unable to free card info\n");
475 /* Not fatal error */
476 }
477 if (card->release_completion)
478 complete(card->release_completion);
479 kfree(card);
480 return 0;
481}
482
483/**
484 * snd_card_free_when_closed - Disconnect the card, free it later eventually
485 * @card: soundcard structure
486 *
487 * Unlike snd_card_free(), this function doesn't try to release the card
488 * resource immediately, but tries to disconnect at first. When the card
489 * is still in use, the function returns before freeing the resources.
490 * The card resources will be freed when the refcount gets to zero.
491 */
492int snd_card_free_when_closed(struct snd_card *card)
493{
494 int ret = snd_card_disconnect(card);
495 if (ret)
496 return ret;
497 put_device(&card->card_dev);
498 return 0;
499}
500EXPORT_SYMBOL(snd_card_free_when_closed);
501
502/**
503 * snd_card_free - frees given soundcard structure
504 * @card: soundcard structure
505 *
506 * This function releases the soundcard structure and the all assigned
507 * devices automatically. That is, you don't have to release the devices
508 * by yourself.
509 *
510 * This function waits until the all resources are properly released.
511 *
512 * Return: Zero. Frees all associated devices and frees the control
513 * interface associated to given soundcard.
514 */
515int snd_card_free(struct snd_card *card)
516{
517 struct completion released;
518 int ret;
519
520 init_completion(&released);
521 card->release_completion = &released;
522 ret = snd_card_free_when_closed(card);
523 if (ret)
524 return ret;
525 /* wait, until all devices are ready for the free operation */
526 wait_for_completion(&released);
527 return 0;
528}
529EXPORT_SYMBOL(snd_card_free);
530
531/* retrieve the last word of shortname or longname */
532static const char *retrieve_id_from_card_name(const char *name)
533{
534 const char *spos = name;
535
536 while (*name) {
537 if (isspace(*name) && isalnum(name[1]))
538 spos = name + 1;
539 name++;
540 }
541 return spos;
542}
543
544/* return true if the given id string doesn't conflict any other card ids */
545static bool card_id_ok(struct snd_card *card, const char *id)
546{
547 int i;
548 if (!snd_info_check_reserved_words(id))
549 return false;
550 for (i = 0; i < snd_ecards_limit; i++) {
551 if (snd_cards[i] && snd_cards[i] != card &&
552 !strcmp(snd_cards[i]->id, id))
553 return false;
554 }
555 return true;
556}
557
558/* copy to card->id only with valid letters from nid */
559static void copy_valid_id_string(struct snd_card *card, const char *src,
560 const char *nid)
561{
562 char *id = card->id;
563
564 while (*nid && !isalnum(*nid))
565 nid++;
566 if (isdigit(*nid))
567 *id++ = isalpha(*src) ? *src : 'D';
568 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
569 if (isalnum(*nid))
570 *id++ = *nid;
571 nid++;
572 }
573 *id = 0;
574}
575
576/* Set card->id from the given string
577 * If the string conflicts with other ids, add a suffix to make it unique.
578 */
579static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
580 const char *nid)
581{
582 int len, loops;
583 bool is_default = false;
584 char *id;
585
586 copy_valid_id_string(card, src, nid);
587 id = card->id;
588
589 again:
590 /* use "Default" for obviously invalid strings
591 * ("card" conflicts with proc directories)
592 */
593 if (!*id || !strncmp(id, "card", 4)) {
594 strcpy(id, "Default");
595 is_default = true;
596 }
597
598 len = strlen(id);
599 for (loops = 0; loops < SNDRV_CARDS; loops++) {
600 char *spos;
601 char sfxstr[5]; /* "_012" */
602 int sfxlen;
603
604 if (card_id_ok(card, id))
605 return; /* OK */
606
607 /* Add _XYZ suffix */
608 sprintf(sfxstr, "_%X", loops + 1);
609 sfxlen = strlen(sfxstr);
610 if (len + sfxlen >= sizeof(card->id))
611 spos = id + sizeof(card->id) - sfxlen - 1;
612 else
613 spos = id + len;
614 strcpy(spos, sfxstr);
615 }
616 /* fallback to the default id */
617 if (!is_default) {
618 *id = 0;
619 goto again;
620 }
621 /* last resort... */
622 dev_err(card->dev, "unable to set card id (%s)\n", id);
623 if (card->proc_root->name)
624 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
625}
626
627/**
628 * snd_card_set_id - set card identification name
629 * @card: soundcard structure
630 * @nid: new identification string
631 *
632 * This function sets the card identification and checks for name
633 * collisions.
634 */
635void snd_card_set_id(struct snd_card *card, const char *nid)
636{
637 /* check if user specified own card->id */
638 if (card->id[0] != '\0')
639 return;
640 mutex_lock(&snd_card_mutex);
641 snd_card_set_id_no_lock(card, nid, nid);
642 mutex_unlock(&snd_card_mutex);
643}
644EXPORT_SYMBOL(snd_card_set_id);
645
646static ssize_t
647card_id_show_attr(struct device *dev,
648 struct device_attribute *attr, char *buf)
649{
650 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
651 return scnprintf(buf, PAGE_SIZE, "%s\n", card->id);
652}
653
654static ssize_t
655card_id_store_attr(struct device *dev, struct device_attribute *attr,
656 const char *buf, size_t count)
657{
658 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
659 char buf1[sizeof(card->id)];
660 size_t copy = count > sizeof(card->id) - 1 ?
661 sizeof(card->id) - 1 : count;
662 size_t idx;
663 int c;
664
665 for (idx = 0; idx < copy; idx++) {
666 c = buf[idx];
667 if (!isalnum(c) && c != '_' && c != '-')
668 return -EINVAL;
669 }
670 memcpy(buf1, buf, copy);
671 buf1[copy] = '\0';
672 mutex_lock(&snd_card_mutex);
673 if (!card_id_ok(NULL, buf1)) {
674 mutex_unlock(&snd_card_mutex);
675 return -EEXIST;
676 }
677 strcpy(card->id, buf1);
678 snd_info_card_id_change(card);
679 mutex_unlock(&snd_card_mutex);
680
681 return count;
682}
683
684static DEVICE_ATTR(id, 0644, card_id_show_attr, card_id_store_attr);
685
686static ssize_t
687card_number_show_attr(struct device *dev,
688 struct device_attribute *attr, char *buf)
689{
690 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
691 return scnprintf(buf, PAGE_SIZE, "%i\n", card->number);
692}
693
694static DEVICE_ATTR(number, 0444, card_number_show_attr, NULL);
695
696static struct attribute *card_dev_attrs[] = {
697 &dev_attr_id.attr,
698 &dev_attr_number.attr,
699 NULL
700};
701
702static const struct attribute_group card_dev_attr_group = {
703 .attrs = card_dev_attrs,
704};
705
706/**
707 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
708 * @card: card instance
709 * @group: attribute group to append
710 */
711int snd_card_add_dev_attr(struct snd_card *card,
712 const struct attribute_group *group)
713{
714 int i;
715
716 /* loop for (arraysize-1) here to keep NULL at the last entry */
717 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
718 if (!card->dev_groups[i]) {
719 card->dev_groups[i] = group;
720 return 0;
721 }
722 }
723
724 dev_err(card->dev, "Too many groups assigned\n");
725 return -ENOSPC;
726}
727EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
728
729/**
730 * snd_card_register - register the soundcard
731 * @card: soundcard structure
732 *
733 * This function registers all the devices assigned to the soundcard.
734 * Until calling this, the ALSA control interface is blocked from the
735 * external accesses. Thus, you should call this function at the end
736 * of the initialization of the card.
737 *
738 * Return: Zero otherwise a negative error code if the registration failed.
739 */
740int snd_card_register(struct snd_card *card)
741{
742 int err;
743
744 if (snd_BUG_ON(!card))
745 return -EINVAL;
746
747 if (!card->registered) {
748 err = device_add(&card->card_dev);
749 if (err < 0)
750 return err;
751 card->registered = true;
752 }
753
754 if ((err = snd_device_register_all(card)) < 0)
755 return err;
756 mutex_lock(&snd_card_mutex);
757 if (snd_cards[card->number]) {
758 /* already registered */
759 mutex_unlock(&snd_card_mutex);
760 return snd_info_card_register(card); /* register pending info */
761 }
762 if (*card->id) {
763 /* make a unique id name from the given string */
764 char tmpid[sizeof(card->id)];
765 memcpy(tmpid, card->id, sizeof(card->id));
766 snd_card_set_id_no_lock(card, tmpid, tmpid);
767 } else {
768 /* create an id from either shortname or longname */
769 const char *src;
770 src = *card->shortname ? card->shortname : card->longname;
771 snd_card_set_id_no_lock(card, src,
772 retrieve_id_from_card_name(src));
773 }
774 snd_cards[card->number] = card;
775 mutex_unlock(&snd_card_mutex);
776 err = snd_info_card_register(card);
777 if (err < 0)
778 return err;
779
780#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
781 if (snd_mixer_oss_notify_callback)
782 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
783#endif
784 return 0;
785}
786EXPORT_SYMBOL(snd_card_register);
787
788#ifdef CONFIG_SND_PROC_FS
789static void snd_card_info_read(struct snd_info_entry *entry,
790 struct snd_info_buffer *buffer)
791{
792 int idx, count;
793 struct snd_card *card;
794
795 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
796 mutex_lock(&snd_card_mutex);
797 if ((card = snd_cards[idx]) != NULL) {
798 count++;
799 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
800 idx,
801 card->id,
802 card->driver,
803 card->shortname);
804 snd_iprintf(buffer, " %s\n",
805 card->longname);
806 }
807 mutex_unlock(&snd_card_mutex);
808 }
809 if (!count)
810 snd_iprintf(buffer, "--- no soundcards ---\n");
811}
812
813#ifdef CONFIG_SND_OSSEMUL
814void snd_card_info_read_oss(struct snd_info_buffer *buffer)
815{
816 int idx, count;
817 struct snd_card *card;
818
819 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
820 mutex_lock(&snd_card_mutex);
821 if ((card = snd_cards[idx]) != NULL) {
822 count++;
823 snd_iprintf(buffer, "%s\n", card->longname);
824 }
825 mutex_unlock(&snd_card_mutex);
826 }
827 if (!count) {
828 snd_iprintf(buffer, "--- no soundcards ---\n");
829 }
830}
831
832#endif
833
834#ifdef MODULE
835static void snd_card_module_info_read(struct snd_info_entry *entry,
836 struct snd_info_buffer *buffer)
837{
838 int idx;
839 struct snd_card *card;
840
841 for (idx = 0; idx < SNDRV_CARDS; idx++) {
842 mutex_lock(&snd_card_mutex);
843 if ((card = snd_cards[idx]) != NULL)
844 snd_iprintf(buffer, "%2i %s\n",
845 idx, card->module->name);
846 mutex_unlock(&snd_card_mutex);
847 }
848}
849#endif
850
851int __init snd_card_info_init(void)
852{
853 struct snd_info_entry *entry;
854
855 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
856 if (! entry)
857 return -ENOMEM;
858 entry->c.text.read = snd_card_info_read;
859 if (snd_info_register(entry) < 0)
860 return -ENOMEM; /* freed in error path */
861
862#ifdef MODULE
863 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
864 if (!entry)
865 return -ENOMEM;
866 entry->c.text.read = snd_card_module_info_read;
867 if (snd_info_register(entry) < 0)
868 return -ENOMEM; /* freed in error path */
869#endif
870
871 return 0;
872}
873#endif /* CONFIG_SND_PROC_FS */
874
875/**
876 * snd_component_add - add a component string
877 * @card: soundcard structure
878 * @component: the component id string
879 *
880 * This function adds the component id string to the supported list.
881 * The component can be referred from the alsa-lib.
882 *
883 * Return: Zero otherwise a negative error code.
884 */
885
886int snd_component_add(struct snd_card *card, const char *component)
887{
888 char *ptr;
889 int len = strlen(component);
890
891 ptr = strstr(card->components, component);
892 if (ptr != NULL) {
893 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
894 return 1;
895 }
896 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
897 snd_BUG();
898 return -ENOMEM;
899 }
900 if (card->components[0] != '\0')
901 strcat(card->components, " ");
902 strcat(card->components, component);
903 return 0;
904}
905EXPORT_SYMBOL(snd_component_add);
906
907/**
908 * snd_card_file_add - add the file to the file list of the card
909 * @card: soundcard structure
910 * @file: file pointer
911 *
912 * This function adds the file to the file linked-list of the card.
913 * This linked-list is used to keep tracking the connection state,
914 * and to avoid the release of busy resources by hotplug.
915 *
916 * Return: zero or a negative error code.
917 */
918int snd_card_file_add(struct snd_card *card, struct file *file)
919{
920 struct snd_monitor_file *mfile;
921
922 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
923 if (mfile == NULL)
924 return -ENOMEM;
925 mfile->file = file;
926 mfile->disconnected_f_op = NULL;
927 INIT_LIST_HEAD(&mfile->shutdown_list);
928 spin_lock(&card->files_lock);
929 if (card->shutdown) {
930 spin_unlock(&card->files_lock);
931 kfree(mfile);
932 return -ENODEV;
933 }
934 list_add(&mfile->list, &card->files_list);
935 get_device(&card->card_dev);
936 spin_unlock(&card->files_lock);
937 return 0;
938}
939EXPORT_SYMBOL(snd_card_file_add);
940
941/**
942 * snd_card_file_remove - remove the file from the file list
943 * @card: soundcard structure
944 * @file: file pointer
945 *
946 * This function removes the file formerly added to the card via
947 * snd_card_file_add() function.
948 * If all files are removed and snd_card_free_when_closed() was
949 * called beforehand, it processes the pending release of
950 * resources.
951 *
952 * Return: Zero or a negative error code.
953 */
954int snd_card_file_remove(struct snd_card *card, struct file *file)
955{
956 struct snd_monitor_file *mfile, *found = NULL;
957
958 spin_lock(&card->files_lock);
959 list_for_each_entry(mfile, &card->files_list, list) {
960 if (mfile->file == file) {
961 list_del(&mfile->list);
962 spin_lock(&shutdown_lock);
963 list_del(&mfile->shutdown_list);
964 spin_unlock(&shutdown_lock);
965 if (mfile->disconnected_f_op)
966 fops_put(mfile->disconnected_f_op);
967 found = mfile;
968 break;
969 }
970 }
971 if (list_empty(&card->files_list))
972 wake_up_all(&card->remove_sleep);
973 spin_unlock(&card->files_lock);
974 if (!found) {
975 dev_err(card->dev, "card file remove problem (%p)\n", file);
976 return -ENOENT;
977 }
978 kfree(found);
979 put_device(&card->card_dev);
980 return 0;
981}
982EXPORT_SYMBOL(snd_card_file_remove);
983
984#ifdef CONFIG_PM
985/**
986 * snd_power_wait - wait until the power-state is changed.
987 * @card: soundcard structure
988 * @power_state: expected power state
989 *
990 * Waits until the power-state is changed.
991 *
992 * Return: Zero if successful, or a negative error code.
993 */
994int snd_power_wait(struct snd_card *card, unsigned int power_state)
995{
996 wait_queue_entry_t wait;
997 int result = 0;
998
999 /* fastpath */
1000 if (snd_power_get_state(card) == power_state)
1001 return 0;
1002 init_waitqueue_entry(&wait, current);
1003 add_wait_queue(&card->power_sleep, &wait);
1004 while (1) {
1005 if (card->shutdown) {
1006 result = -ENODEV;
1007 break;
1008 }
1009 if (snd_power_get_state(card) == power_state)
1010 break;
1011 set_current_state(TASK_UNINTERRUPTIBLE);
1012 schedule_timeout(30 * HZ);
1013 }
1014 remove_wait_queue(&card->power_sleep, &wait);
1015 return result;
1016}
1017EXPORT_SYMBOL(snd_power_wait);
1018#endif /* CONFIG_PM */
1/*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/init.h>
23#include <linux/sched.h>
24#include <linux/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 */