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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#ifdef MODULE
207 WARN_ON(!module);
208 card->module = module;
209#endif
210 INIT_LIST_HEAD(&card->devices);
211 init_rwsem(&card->controls_rwsem);
212 rwlock_init(&card->ctl_files_rwlock);
213 INIT_LIST_HEAD(&card->controls);
214 INIT_LIST_HEAD(&card->ctl_files);
215 spin_lock_init(&card->files_lock);
216 INIT_LIST_HEAD(&card->files_list);
217 mutex_init(&card->memory_mutex);
218#ifdef CONFIG_PM
219 init_waitqueue_head(&card->power_sleep);
220#endif
221 init_waitqueue_head(&card->remove_sleep);
222 card->sync_irq = -1;
223
224 device_initialize(&card->card_dev);
225 card->card_dev.parent = parent;
226 card->card_dev.class = sound_class;
227 card->card_dev.release = release_card_device;
228 card->card_dev.groups = card->dev_groups;
229 card->dev_groups[0] = &card_dev_attr_group;
230 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
231 if (err < 0)
232 goto __error;
233
234 snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
235 dev_driver_string(card->dev), dev_name(&card->card_dev));
236
237 /* the control interface cannot be accessed from the user space until */
238 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
239 err = snd_ctl_create(card);
240 if (err < 0) {
241 dev_err(parent, "unable to register control minors\n");
242 goto __error;
243 }
244 err = snd_info_card_create(card);
245 if (err < 0) {
246 dev_err(parent, "unable to create card info\n");
247 goto __error_ctl;
248 }
249 *card_ret = card;
250 return 0;
251
252 __error_ctl:
253 snd_device_free_all(card);
254 __error:
255 put_device(&card->card_dev);
256 return err;
257}
258EXPORT_SYMBOL(snd_card_new);
259
260/**
261 * snd_card_ref - Get the card object from the index
262 * @idx: the card index
263 *
264 * Returns a card object corresponding to the given index or NULL if not found.
265 * Release the object via snd_card_unref().
266 */
267struct snd_card *snd_card_ref(int idx)
268{
269 struct snd_card *card;
270
271 mutex_lock(&snd_card_mutex);
272 card = snd_cards[idx];
273 if (card)
274 get_device(&card->card_dev);
275 mutex_unlock(&snd_card_mutex);
276 return card;
277}
278EXPORT_SYMBOL_GPL(snd_card_ref);
279
280/* return non-zero if a card is already locked */
281int snd_card_locked(int card)
282{
283 int locked;
284
285 mutex_lock(&snd_card_mutex);
286 locked = test_bit(card, snd_cards_lock);
287 mutex_unlock(&snd_card_mutex);
288 return locked;
289}
290
291static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
292{
293 return -ENODEV;
294}
295
296static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
297 size_t count, loff_t *offset)
298{
299 return -ENODEV;
300}
301
302static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
303 size_t count, loff_t *offset)
304{
305 return -ENODEV;
306}
307
308static int snd_disconnect_release(struct inode *inode, struct file *file)
309{
310 struct snd_monitor_file *df = NULL, *_df;
311
312 spin_lock(&shutdown_lock);
313 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
314 if (_df->file == file) {
315 df = _df;
316 list_del_init(&df->shutdown_list);
317 break;
318 }
319 }
320 spin_unlock(&shutdown_lock);
321
322 if (likely(df)) {
323 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
324 df->disconnected_f_op->fasync(-1, file, 0);
325 return df->disconnected_f_op->release(inode, file);
326 }
327
328 panic("%s(%p, %p) failed!", __func__, inode, file);
329}
330
331static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
332{
333 return EPOLLERR | EPOLLNVAL;
334}
335
336static long snd_disconnect_ioctl(struct file *file,
337 unsigned int cmd, unsigned long arg)
338{
339 return -ENODEV;
340}
341
342static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
343{
344 return -ENODEV;
345}
346
347static int snd_disconnect_fasync(int fd, struct file *file, int on)
348{
349 return -ENODEV;
350}
351
352static const struct file_operations snd_shutdown_f_ops =
353{
354 .owner = THIS_MODULE,
355 .llseek = snd_disconnect_llseek,
356 .read = snd_disconnect_read,
357 .write = snd_disconnect_write,
358 .release = snd_disconnect_release,
359 .poll = snd_disconnect_poll,
360 .unlocked_ioctl = snd_disconnect_ioctl,
361#ifdef CONFIG_COMPAT
362 .compat_ioctl = snd_disconnect_ioctl,
363#endif
364 .mmap = snd_disconnect_mmap,
365 .fasync = snd_disconnect_fasync
366};
367
368/**
369 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
370 * @card: soundcard structure
371 *
372 * Disconnects all APIs from the file-operations (user space).
373 *
374 * Return: Zero, otherwise a negative error code.
375 *
376 * Note: The current implementation replaces all active file->f_op with special
377 * dummy file operations (they do nothing except release).
378 */
379int snd_card_disconnect(struct snd_card *card)
380{
381 struct snd_monitor_file *mfile;
382
383 if (!card)
384 return -EINVAL;
385
386 spin_lock(&card->files_lock);
387 if (card->shutdown) {
388 spin_unlock(&card->files_lock);
389 return 0;
390 }
391 card->shutdown = 1;
392 spin_unlock(&card->files_lock);
393
394 /* replace file->f_op with special dummy operations */
395 spin_lock(&card->files_lock);
396 list_for_each_entry(mfile, &card->files_list, list) {
397 /* it's critical part, use endless loop */
398 /* we have no room to fail */
399 mfile->disconnected_f_op = mfile->file->f_op;
400
401 spin_lock(&shutdown_lock);
402 list_add(&mfile->shutdown_list, &shutdown_files);
403 spin_unlock(&shutdown_lock);
404
405 mfile->file->f_op = &snd_shutdown_f_ops;
406 fops_get(mfile->file->f_op);
407 }
408 spin_unlock(&card->files_lock);
409
410 /* notify all connected devices about disconnection */
411 /* at this point, they cannot respond to any calls except release() */
412
413#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
414 if (snd_mixer_oss_notify_callback)
415 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
416#endif
417
418 /* notify all devices that we are disconnected */
419 snd_device_disconnect_all(card);
420
421 snd_info_card_disconnect(card);
422 if (card->registered) {
423 device_del(&card->card_dev);
424 card->registered = false;
425 }
426
427 /* disable fops (user space) operations for ALSA API */
428 mutex_lock(&snd_card_mutex);
429 snd_cards[card->number] = NULL;
430 clear_bit(card->number, snd_cards_lock);
431 mutex_unlock(&snd_card_mutex);
432
433#ifdef CONFIG_PM
434 wake_up(&card->power_sleep);
435#endif
436 return 0;
437}
438EXPORT_SYMBOL(snd_card_disconnect);
439
440/**
441 * snd_card_disconnect_sync - disconnect card and wait until files get closed
442 * @card: card object to disconnect
443 *
444 * This calls snd_card_disconnect() for disconnecting all belonging components
445 * and waits until all pending files get closed.
446 * It assures that all accesses from user-space finished so that the driver
447 * can release its resources gracefully.
448 */
449void snd_card_disconnect_sync(struct snd_card *card)
450{
451 int err;
452
453 err = snd_card_disconnect(card);
454 if (err < 0) {
455 dev_err(card->dev,
456 "snd_card_disconnect error (%d), skipping sync\n",
457 err);
458 return;
459 }
460
461 spin_lock_irq(&card->files_lock);
462 wait_event_lock_irq(card->remove_sleep,
463 list_empty(&card->files_list),
464 card->files_lock);
465 spin_unlock_irq(&card->files_lock);
466}
467EXPORT_SYMBOL_GPL(snd_card_disconnect_sync);
468
469static int snd_card_do_free(struct snd_card *card)
470{
471#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
472 if (snd_mixer_oss_notify_callback)
473 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
474#endif
475 snd_device_free_all(card);
476 if (card->private_free)
477 card->private_free(card);
478 if (snd_info_card_free(card) < 0) {
479 dev_warn(card->dev, "unable to free card info\n");
480 /* Not fatal error */
481 }
482 if (card->release_completion)
483 complete(card->release_completion);
484 kfree(card);
485 return 0;
486}
487
488/**
489 * snd_card_free_when_closed - Disconnect the card, free it later eventually
490 * @card: soundcard structure
491 *
492 * Unlike snd_card_free(), this function doesn't try to release the card
493 * resource immediately, but tries to disconnect at first. When the card
494 * is still in use, the function returns before freeing the resources.
495 * The card resources will be freed when the refcount gets to zero.
496 */
497int snd_card_free_when_closed(struct snd_card *card)
498{
499 int ret = snd_card_disconnect(card);
500 if (ret)
501 return ret;
502 put_device(&card->card_dev);
503 return 0;
504}
505EXPORT_SYMBOL(snd_card_free_when_closed);
506
507/**
508 * snd_card_free - frees given soundcard structure
509 * @card: soundcard structure
510 *
511 * This function releases the soundcard structure and the all assigned
512 * devices automatically. That is, you don't have to release the devices
513 * by yourself.
514 *
515 * This function waits until the all resources are properly released.
516 *
517 * Return: Zero. Frees all associated devices and frees the control
518 * interface associated to given soundcard.
519 */
520int snd_card_free(struct snd_card *card)
521{
522 struct completion released;
523 int ret;
524
525 init_completion(&released);
526 card->release_completion = &released;
527 ret = snd_card_free_when_closed(card);
528 if (ret)
529 return ret;
530 /* wait, until all devices are ready for the free operation */
531 wait_for_completion(&released);
532 return 0;
533}
534EXPORT_SYMBOL(snd_card_free);
535
536/* retrieve the last word of shortname or longname */
537static const char *retrieve_id_from_card_name(const char *name)
538{
539 const char *spos = name;
540
541 while (*name) {
542 if (isspace(*name) && isalnum(name[1]))
543 spos = name + 1;
544 name++;
545 }
546 return spos;
547}
548
549/* return true if the given id string doesn't conflict any other card ids */
550static bool card_id_ok(struct snd_card *card, const char *id)
551{
552 int i;
553 if (!snd_info_check_reserved_words(id))
554 return false;
555 for (i = 0; i < snd_ecards_limit; i++) {
556 if (snd_cards[i] && snd_cards[i] != card &&
557 !strcmp(snd_cards[i]->id, id))
558 return false;
559 }
560 return true;
561}
562
563/* copy to card->id only with valid letters from nid */
564static void copy_valid_id_string(struct snd_card *card, const char *src,
565 const char *nid)
566{
567 char *id = card->id;
568
569 while (*nid && !isalnum(*nid))
570 nid++;
571 if (isdigit(*nid))
572 *id++ = isalpha(*src) ? *src : 'D';
573 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
574 if (isalnum(*nid))
575 *id++ = *nid;
576 nid++;
577 }
578 *id = 0;
579}
580
581/* Set card->id from the given string
582 * If the string conflicts with other ids, add a suffix to make it unique.
583 */
584static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
585 const char *nid)
586{
587 int len, loops;
588 bool is_default = false;
589 char *id;
590
591 copy_valid_id_string(card, src, nid);
592 id = card->id;
593
594 again:
595 /* use "Default" for obviously invalid strings
596 * ("card" conflicts with proc directories)
597 */
598 if (!*id || !strncmp(id, "card", 4)) {
599 strcpy(id, "Default");
600 is_default = true;
601 }
602
603 len = strlen(id);
604 for (loops = 0; loops < SNDRV_CARDS; loops++) {
605 char *spos;
606 char sfxstr[5]; /* "_012" */
607 int sfxlen;
608
609 if (card_id_ok(card, id))
610 return; /* OK */
611
612 /* Add _XYZ suffix */
613 sprintf(sfxstr, "_%X", loops + 1);
614 sfxlen = strlen(sfxstr);
615 if (len + sfxlen >= sizeof(card->id))
616 spos = id + sizeof(card->id) - sfxlen - 1;
617 else
618 spos = id + len;
619 strcpy(spos, sfxstr);
620 }
621 /* fallback to the default id */
622 if (!is_default) {
623 *id = 0;
624 goto again;
625 }
626 /* last resort... */
627 dev_err(card->dev, "unable to set card id (%s)\n", id);
628 if (card->proc_root->name)
629 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
630}
631
632/**
633 * snd_card_set_id - set card identification name
634 * @card: soundcard structure
635 * @nid: new identification string
636 *
637 * This function sets the card identification and checks for name
638 * collisions.
639 */
640void snd_card_set_id(struct snd_card *card, const char *nid)
641{
642 /* check if user specified own card->id */
643 if (card->id[0] != '\0')
644 return;
645 mutex_lock(&snd_card_mutex);
646 snd_card_set_id_no_lock(card, nid, nid);
647 mutex_unlock(&snd_card_mutex);
648}
649EXPORT_SYMBOL(snd_card_set_id);
650
651static ssize_t
652card_id_show_attr(struct device *dev,
653 struct device_attribute *attr, char *buf)
654{
655 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
656 return scnprintf(buf, PAGE_SIZE, "%s\n", card->id);
657}
658
659static ssize_t
660card_id_store_attr(struct device *dev, struct device_attribute *attr,
661 const char *buf, size_t count)
662{
663 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
664 char buf1[sizeof(card->id)];
665 size_t copy = count > sizeof(card->id) - 1 ?
666 sizeof(card->id) - 1 : count;
667 size_t idx;
668 int c;
669
670 for (idx = 0; idx < copy; idx++) {
671 c = buf[idx];
672 if (!isalnum(c) && c != '_' && c != '-')
673 return -EINVAL;
674 }
675 memcpy(buf1, buf, copy);
676 buf1[copy] = '\0';
677 mutex_lock(&snd_card_mutex);
678 if (!card_id_ok(NULL, buf1)) {
679 mutex_unlock(&snd_card_mutex);
680 return -EEXIST;
681 }
682 strcpy(card->id, buf1);
683 snd_info_card_id_change(card);
684 mutex_unlock(&snd_card_mutex);
685
686 return count;
687}
688
689static DEVICE_ATTR(id, 0644, card_id_show_attr, card_id_store_attr);
690
691static ssize_t
692card_number_show_attr(struct device *dev,
693 struct device_attribute *attr, char *buf)
694{
695 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
696 return scnprintf(buf, PAGE_SIZE, "%i\n", card->number);
697}
698
699static DEVICE_ATTR(number, 0444, card_number_show_attr, NULL);
700
701static struct attribute *card_dev_attrs[] = {
702 &dev_attr_id.attr,
703 &dev_attr_number.attr,
704 NULL
705};
706
707static const struct attribute_group card_dev_attr_group = {
708 .attrs = card_dev_attrs,
709};
710
711/**
712 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
713 * @card: card instance
714 * @group: attribute group to append
715 */
716int snd_card_add_dev_attr(struct snd_card *card,
717 const struct attribute_group *group)
718{
719 int i;
720
721 /* loop for (arraysize-1) here to keep NULL at the last entry */
722 for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
723 if (!card->dev_groups[i]) {
724 card->dev_groups[i] = group;
725 return 0;
726 }
727 }
728
729 dev_err(card->dev, "Too many groups assigned\n");
730 return -ENOSPC;
731}
732EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
733
734/**
735 * snd_card_register - register the soundcard
736 * @card: soundcard structure
737 *
738 * This function registers all the devices assigned to the soundcard.
739 * Until calling this, the ALSA control interface is blocked from the
740 * external accesses. Thus, you should call this function at the end
741 * of the initialization of the card.
742 *
743 * Return: Zero otherwise a negative error code if the registration failed.
744 */
745int snd_card_register(struct snd_card *card)
746{
747 int err;
748
749 if (snd_BUG_ON(!card))
750 return -EINVAL;
751
752 if (!card->registered) {
753 err = device_add(&card->card_dev);
754 if (err < 0)
755 return err;
756 card->registered = true;
757 }
758
759 if ((err = snd_device_register_all(card)) < 0)
760 return err;
761 mutex_lock(&snd_card_mutex);
762 if (snd_cards[card->number]) {
763 /* already registered */
764 mutex_unlock(&snd_card_mutex);
765 return snd_info_card_register(card); /* register pending info */
766 }
767 if (*card->id) {
768 /* make a unique id name from the given string */
769 char tmpid[sizeof(card->id)];
770 memcpy(tmpid, card->id, sizeof(card->id));
771 snd_card_set_id_no_lock(card, tmpid, tmpid);
772 } else {
773 /* create an id from either shortname or longname */
774 const char *src;
775 src = *card->shortname ? card->shortname : card->longname;
776 snd_card_set_id_no_lock(card, src,
777 retrieve_id_from_card_name(src));
778 }
779 snd_cards[card->number] = card;
780 mutex_unlock(&snd_card_mutex);
781 err = snd_info_card_register(card);
782 if (err < 0)
783 return err;
784
785#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
786 if (snd_mixer_oss_notify_callback)
787 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
788#endif
789 return 0;
790}
791EXPORT_SYMBOL(snd_card_register);
792
793#ifdef CONFIG_SND_PROC_FS
794static void snd_card_info_read(struct snd_info_entry *entry,
795 struct snd_info_buffer *buffer)
796{
797 int idx, count;
798 struct snd_card *card;
799
800 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
801 mutex_lock(&snd_card_mutex);
802 if ((card = snd_cards[idx]) != NULL) {
803 count++;
804 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
805 idx,
806 card->id,
807 card->driver,
808 card->shortname);
809 snd_iprintf(buffer, " %s\n",
810 card->longname);
811 }
812 mutex_unlock(&snd_card_mutex);
813 }
814 if (!count)
815 snd_iprintf(buffer, "--- no soundcards ---\n");
816}
817
818#ifdef CONFIG_SND_OSSEMUL
819void snd_card_info_read_oss(struct snd_info_buffer *buffer)
820{
821 int idx, count;
822 struct snd_card *card;
823
824 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
825 mutex_lock(&snd_card_mutex);
826 if ((card = snd_cards[idx]) != NULL) {
827 count++;
828 snd_iprintf(buffer, "%s\n", card->longname);
829 }
830 mutex_unlock(&snd_card_mutex);
831 }
832 if (!count) {
833 snd_iprintf(buffer, "--- no soundcards ---\n");
834 }
835}
836
837#endif
838
839#ifdef MODULE
840static void snd_card_module_info_read(struct snd_info_entry *entry,
841 struct snd_info_buffer *buffer)
842{
843 int idx;
844 struct snd_card *card;
845
846 for (idx = 0; idx < SNDRV_CARDS; idx++) {
847 mutex_lock(&snd_card_mutex);
848 if ((card = snd_cards[idx]) != NULL)
849 snd_iprintf(buffer, "%2i %s\n",
850 idx, card->module->name);
851 mutex_unlock(&snd_card_mutex);
852 }
853}
854#endif
855
856int __init snd_card_info_init(void)
857{
858 struct snd_info_entry *entry;
859
860 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
861 if (! entry)
862 return -ENOMEM;
863 entry->c.text.read = snd_card_info_read;
864 if (snd_info_register(entry) < 0)
865 return -ENOMEM; /* freed in error path */
866
867#ifdef MODULE
868 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
869 if (!entry)
870 return -ENOMEM;
871 entry->c.text.read = snd_card_module_info_read;
872 if (snd_info_register(entry) < 0)
873 return -ENOMEM; /* freed in error path */
874#endif
875
876 return 0;
877}
878#endif /* CONFIG_SND_PROC_FS */
879
880/**
881 * snd_component_add - add a component string
882 * @card: soundcard structure
883 * @component: the component id string
884 *
885 * This function adds the component id string to the supported list.
886 * The component can be referred from the alsa-lib.
887 *
888 * Return: Zero otherwise a negative error code.
889 */
890
891int snd_component_add(struct snd_card *card, const char *component)
892{
893 char *ptr;
894 int len = strlen(component);
895
896 ptr = strstr(card->components, component);
897 if (ptr != NULL) {
898 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
899 return 1;
900 }
901 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
902 snd_BUG();
903 return -ENOMEM;
904 }
905 if (card->components[0] != '\0')
906 strcat(card->components, " ");
907 strcat(card->components, component);
908 return 0;
909}
910EXPORT_SYMBOL(snd_component_add);
911
912/**
913 * snd_card_file_add - add the file to the file list of the card
914 * @card: soundcard structure
915 * @file: file pointer
916 *
917 * This function adds the file to the file linked-list of the card.
918 * This linked-list is used to keep tracking the connection state,
919 * and to avoid the release of busy resources by hotplug.
920 *
921 * Return: zero or a negative error code.
922 */
923int snd_card_file_add(struct snd_card *card, struct file *file)
924{
925 struct snd_monitor_file *mfile;
926
927 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
928 if (mfile == NULL)
929 return -ENOMEM;
930 mfile->file = file;
931 mfile->disconnected_f_op = NULL;
932 INIT_LIST_HEAD(&mfile->shutdown_list);
933 spin_lock(&card->files_lock);
934 if (card->shutdown) {
935 spin_unlock(&card->files_lock);
936 kfree(mfile);
937 return -ENODEV;
938 }
939 list_add(&mfile->list, &card->files_list);
940 get_device(&card->card_dev);
941 spin_unlock(&card->files_lock);
942 return 0;
943}
944EXPORT_SYMBOL(snd_card_file_add);
945
946/**
947 * snd_card_file_remove - remove the file from the file list
948 * @card: soundcard structure
949 * @file: file pointer
950 *
951 * This function removes the file formerly added to the card via
952 * snd_card_file_add() function.
953 * If all files are removed and snd_card_free_when_closed() was
954 * called beforehand, it processes the pending release of
955 * resources.
956 *
957 * Return: Zero or a negative error code.
958 */
959int snd_card_file_remove(struct snd_card *card, struct file *file)
960{
961 struct snd_monitor_file *mfile, *found = NULL;
962
963 spin_lock(&card->files_lock);
964 list_for_each_entry(mfile, &card->files_list, list) {
965 if (mfile->file == file) {
966 list_del(&mfile->list);
967 spin_lock(&shutdown_lock);
968 list_del(&mfile->shutdown_list);
969 spin_unlock(&shutdown_lock);
970 if (mfile->disconnected_f_op)
971 fops_put(mfile->disconnected_f_op);
972 found = mfile;
973 break;
974 }
975 }
976 if (list_empty(&card->files_list))
977 wake_up_all(&card->remove_sleep);
978 spin_unlock(&card->files_lock);
979 if (!found) {
980 dev_err(card->dev, "card file remove problem (%p)\n", file);
981 return -ENOENT;
982 }
983 kfree(found);
984 put_device(&card->card_dev);
985 return 0;
986}
987EXPORT_SYMBOL(snd_card_file_remove);
988
989#ifdef CONFIG_PM
990/**
991 * snd_power_wait - wait until the power-state is changed.
992 * @card: soundcard structure
993 * @power_state: expected power state
994 *
995 * Waits until the power-state is changed.
996 *
997 * Return: Zero if successful, or a negative error code.
998 */
999int snd_power_wait(struct snd_card *card, unsigned int power_state)
1000{
1001 wait_queue_entry_t wait;
1002 int result = 0;
1003
1004 /* fastpath */
1005 if (snd_power_get_state(card) == power_state)
1006 return 0;
1007 init_waitqueue_entry(&wait, current);
1008 add_wait_queue(&card->power_sleep, &wait);
1009 while (1) {
1010 if (card->shutdown) {
1011 result = -ENODEV;
1012 break;
1013 }
1014 if (snd_power_get_state(card) == power_state)
1015 break;
1016 set_current_state(TASK_UNINTERRUPTIBLE);
1017 schedule_timeout(30 * HZ);
1018 }
1019 remove_wait_queue(&card->power_sleep, &wait);
1020 return result;
1021}
1022EXPORT_SYMBOL(snd_power_wait);
1023#endif /* CONFIG_PM */
1/*
2 * Initialization routines
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/init.h>
23#include <linux/sched.h>
24#include <linux/module.h>
25#include <linux/device.h>
26#include <linux/file.h>
27#include <linux/slab.h>
28#include <linux/time.h>
29#include <linux/ctype.h>
30#include <linux/pm.h>
31#include <linux/completion.h>
32
33#include <sound/core.h>
34#include <sound/control.h>
35#include <sound/info.h>
36
37/* monitor files for graceful shutdown (hotplug) */
38struct snd_monitor_file {
39 struct file *file;
40 const struct file_operations *disconnected_f_op;
41 struct list_head shutdown_list; /* still need to shutdown */
42 struct list_head list; /* link of monitor files */
43};
44
45static DEFINE_SPINLOCK(shutdown_lock);
46static LIST_HEAD(shutdown_files);
47
48static const struct file_operations snd_shutdown_f_ops;
49
50/* locked for registering/using */
51static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
52struct snd_card *snd_cards[SNDRV_CARDS];
53EXPORT_SYMBOL(snd_cards);
54
55static DEFINE_MUTEX(snd_card_mutex);
56
57static char *slots[SNDRV_CARDS];
58module_param_array(slots, charp, NULL, 0444);
59MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
60
61/* return non-zero if the given index is reserved for the given
62 * module via slots option
63 */
64static int module_slot_match(struct module *module, int idx)
65{
66 int match = 1;
67#ifdef MODULE
68 const char *s1, *s2;
69
70 if (!module || !*module->name || !slots[idx])
71 return 0;
72
73 s1 = module->name;
74 s2 = slots[idx];
75 if (*s2 == '!') {
76 match = 0; /* negative match */
77 s2++;
78 }
79 /* compare module name strings
80 * hyphens are handled as equivalent with underscore
81 */
82 for (;;) {
83 char c1 = *s1++;
84 char c2 = *s2++;
85 if (c1 == '-')
86 c1 = '_';
87 if (c2 == '-')
88 c2 = '_';
89 if (c1 != c2)
90 return !match;
91 if (!c1)
92 break;
93 }
94#endif /* MODULE */
95 return match;
96}
97
98#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
99int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
100EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
101#endif
102
103#ifdef CONFIG_PROC_FS
104static void snd_card_id_read(struct snd_info_entry *entry,
105 struct snd_info_buffer *buffer)
106{
107 snd_iprintf(buffer, "%s\n", entry->card->id);
108}
109
110static inline int init_info_for_card(struct snd_card *card)
111{
112 int err;
113 struct snd_info_entry *entry;
114
115 if ((err = snd_info_card_register(card)) < 0) {
116 dev_dbg(card->dev, "unable to create card info\n");
117 return err;
118 }
119 if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
120 dev_dbg(card->dev, "unable to create card entry\n");
121 return err;
122 }
123 entry->c.text.read = snd_card_id_read;
124 if (snd_info_register(entry) < 0) {
125 snd_info_free_entry(entry);
126 entry = NULL;
127 }
128 card->proc_id = entry;
129 return 0;
130}
131#else /* !CONFIG_PROC_FS */
132#define init_info_for_card(card)
133#endif
134
135static int check_empty_slot(struct module *module, int slot)
136{
137 return !slots[slot] || !*slots[slot];
138}
139
140/* return an empty slot number (>= 0) found in the given bitmask @mask.
141 * @mask == -1 == 0xffffffff means: take any free slot up to 32
142 * when no slot is available, return the original @mask as is.
143 */
144static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
145 struct module *module)
146{
147 int slot;
148
149 for (slot = 0; slot < SNDRV_CARDS; slot++) {
150 if (slot < 32 && !(mask & (1U << slot)))
151 continue;
152 if (!test_bit(slot, snd_cards_lock)) {
153 if (check(module, slot))
154 return slot; /* found */
155 }
156 }
157 return mask; /* unchanged */
158}
159
160static int snd_card_do_free(struct snd_card *card);
161static const struct attribute_group *card_dev_attr_groups[];
162
163static void release_card_device(struct device *dev)
164{
165 snd_card_do_free(dev_to_snd_card(dev));
166}
167
168/**
169 * snd_card_new - create and initialize a soundcard structure
170 * @parent: the parent device object
171 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
172 * @xid: card identification (ASCII string)
173 * @module: top level module for locking
174 * @extra_size: allocate this extra size after the main soundcard structure
175 * @card_ret: the pointer to store the created card instance
176 *
177 * Creates and initializes a soundcard structure.
178 *
179 * The function allocates snd_card instance via kzalloc with the given
180 * space for the driver to use freely. The allocated struct is stored
181 * in the given card_ret pointer.
182 *
183 * Return: Zero if successful or a negative error code.
184 */
185int snd_card_new(struct device *parent, int idx, const char *xid,
186 struct module *module, int extra_size,
187 struct snd_card **card_ret)
188{
189 struct snd_card *card;
190 int err;
191
192 if (snd_BUG_ON(!card_ret))
193 return -EINVAL;
194 *card_ret = NULL;
195
196 if (extra_size < 0)
197 extra_size = 0;
198 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
199 if (!card)
200 return -ENOMEM;
201 if (extra_size > 0)
202 card->private_data = (char *)card + sizeof(struct snd_card);
203 if (xid)
204 strlcpy(card->id, xid, sizeof(card->id));
205 err = 0;
206 mutex_lock(&snd_card_mutex);
207 if (idx < 0) /* first check the matching module-name slot */
208 idx = get_slot_from_bitmask(idx, module_slot_match, module);
209 if (idx < 0) /* if not matched, assign an empty slot */
210 idx = get_slot_from_bitmask(idx, check_empty_slot, module);
211 if (idx < 0)
212 err = -ENODEV;
213 else if (idx < snd_ecards_limit) {
214 if (test_bit(idx, snd_cards_lock))
215 err = -EBUSY; /* invalid */
216 } else if (idx >= SNDRV_CARDS)
217 err = -ENODEV;
218 if (err < 0) {
219 mutex_unlock(&snd_card_mutex);
220 dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
221 idx, snd_ecards_limit - 1, err);
222 kfree(card);
223 return err;
224 }
225 set_bit(idx, snd_cards_lock); /* lock it */
226 if (idx >= snd_ecards_limit)
227 snd_ecards_limit = idx + 1; /* increase the limit */
228 mutex_unlock(&snd_card_mutex);
229 card->dev = parent;
230 card->number = idx;
231 card->module = module;
232 INIT_LIST_HEAD(&card->devices);
233 init_rwsem(&card->controls_rwsem);
234 rwlock_init(&card->ctl_files_rwlock);
235 INIT_LIST_HEAD(&card->controls);
236 INIT_LIST_HEAD(&card->ctl_files);
237 spin_lock_init(&card->files_lock);
238 INIT_LIST_HEAD(&card->files_list);
239#ifdef CONFIG_PM
240 mutex_init(&card->power_lock);
241 init_waitqueue_head(&card->power_sleep);
242#endif
243
244 device_initialize(&card->card_dev);
245 card->card_dev.parent = parent;
246 card->card_dev.class = sound_class;
247 card->card_dev.release = release_card_device;
248 card->card_dev.groups = card_dev_attr_groups;
249 err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
250 if (err < 0)
251 goto __error;
252
253 /* the control interface cannot be accessed from the user space until */
254 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
255 err = snd_ctl_create(card);
256 if (err < 0) {
257 dev_err(parent, "unable to register control minors\n");
258 goto __error;
259 }
260 err = snd_info_card_create(card);
261 if (err < 0) {
262 dev_err(parent, "unable to create card info\n");
263 goto __error_ctl;
264 }
265 *card_ret = card;
266 return 0;
267
268 __error_ctl:
269 snd_device_free_all(card);
270 __error:
271 put_device(&card->card_dev);
272 return err;
273}
274EXPORT_SYMBOL(snd_card_new);
275
276/* return non-zero if a card is already locked */
277int snd_card_locked(int card)
278{
279 int locked;
280
281 mutex_lock(&snd_card_mutex);
282 locked = test_bit(card, snd_cards_lock);
283 mutex_unlock(&snd_card_mutex);
284 return locked;
285}
286
287static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
288{
289 return -ENODEV;
290}
291
292static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
293 size_t count, loff_t *offset)
294{
295 return -ENODEV;
296}
297
298static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
299 size_t count, loff_t *offset)
300{
301 return -ENODEV;
302}
303
304static int snd_disconnect_release(struct inode *inode, struct file *file)
305{
306 struct snd_monitor_file *df = NULL, *_df;
307
308 spin_lock(&shutdown_lock);
309 list_for_each_entry(_df, &shutdown_files, shutdown_list) {
310 if (_df->file == file) {
311 df = _df;
312 list_del_init(&df->shutdown_list);
313 break;
314 }
315 }
316 spin_unlock(&shutdown_lock);
317
318 if (likely(df)) {
319 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
320 df->disconnected_f_op->fasync(-1, file, 0);
321 return df->disconnected_f_op->release(inode, file);
322 }
323
324 panic("%s(%p, %p) failed!", __func__, inode, file);
325}
326
327static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
328{
329 return POLLERR | POLLNVAL;
330}
331
332static long snd_disconnect_ioctl(struct file *file,
333 unsigned int cmd, unsigned long arg)
334{
335 return -ENODEV;
336}
337
338static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
339{
340 return -ENODEV;
341}
342
343static int snd_disconnect_fasync(int fd, struct file *file, int on)
344{
345 return -ENODEV;
346}
347
348static const struct file_operations snd_shutdown_f_ops =
349{
350 .owner = THIS_MODULE,
351 .llseek = snd_disconnect_llseek,
352 .read = snd_disconnect_read,
353 .write = snd_disconnect_write,
354 .release = snd_disconnect_release,
355 .poll = snd_disconnect_poll,
356 .unlocked_ioctl = snd_disconnect_ioctl,
357#ifdef CONFIG_COMPAT
358 .compat_ioctl = snd_disconnect_ioctl,
359#endif
360 .mmap = snd_disconnect_mmap,
361 .fasync = snd_disconnect_fasync
362};
363
364/**
365 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
366 * @card: soundcard structure
367 *
368 * Disconnects all APIs from the file-operations (user space).
369 *
370 * Return: Zero, otherwise a negative error code.
371 *
372 * Note: The current implementation replaces all active file->f_op with special
373 * dummy file operations (they do nothing except release).
374 */
375int snd_card_disconnect(struct snd_card *card)
376{
377 struct snd_monitor_file *mfile;
378 int err;
379
380 if (!card)
381 return -EINVAL;
382
383 spin_lock(&card->files_lock);
384 if (card->shutdown) {
385 spin_unlock(&card->files_lock);
386 return 0;
387 }
388 card->shutdown = 1;
389 spin_unlock(&card->files_lock);
390
391 /* phase 1: disable fops (user space) operations for ALSA API */
392 mutex_lock(&snd_card_mutex);
393 snd_cards[card->number] = NULL;
394 clear_bit(card->number, snd_cards_lock);
395 mutex_unlock(&snd_card_mutex);
396
397 /* phase 2: replace file->f_op with special dummy operations */
398
399 spin_lock(&card->files_lock);
400 list_for_each_entry(mfile, &card->files_list, list) {
401 /* it's critical part, use endless loop */
402 /* we have no room to fail */
403 mfile->disconnected_f_op = mfile->file->f_op;
404
405 spin_lock(&shutdown_lock);
406 list_add(&mfile->shutdown_list, &shutdown_files);
407 spin_unlock(&shutdown_lock);
408
409 mfile->file->f_op = &snd_shutdown_f_ops;
410 fops_get(mfile->file->f_op);
411 }
412 spin_unlock(&card->files_lock);
413
414 /* phase 3: notify all connected devices about disconnection */
415 /* at this point, they cannot respond to any calls except release() */
416
417#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
418 if (snd_mixer_oss_notify_callback)
419 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
420#endif
421
422 /* notify all devices that we are disconnected */
423 err = snd_device_disconnect_all(card);
424 if (err < 0)
425 dev_err(card->dev, "not all devices for card %i can be disconnected\n", card->number);
426
427 snd_info_card_disconnect(card);
428 if (card->registered) {
429 device_del(&card->card_dev);
430 card->registered = false;
431 }
432#ifdef CONFIG_PM
433 wake_up(&card->power_sleep);
434#endif
435 return 0;
436}
437
438EXPORT_SYMBOL(snd_card_disconnect);
439
440/**
441 * snd_card_free - frees given soundcard structure
442 * @card: soundcard structure
443 *
444 * This function releases the soundcard structure and the all assigned
445 * devices automatically. That is, you don't have to release the devices
446 * by yourself.
447 *
448 * Return: Zero. Frees all associated devices and frees the control
449 * interface associated to given soundcard.
450 */
451static int snd_card_do_free(struct snd_card *card)
452{
453#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
454 if (snd_mixer_oss_notify_callback)
455 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
456#endif
457 snd_device_free_all(card);
458 if (card->private_free)
459 card->private_free(card);
460 snd_info_free_entry(card->proc_id);
461 if (snd_info_card_free(card) < 0) {
462 dev_warn(card->dev, "unable to free card info\n");
463 /* Not fatal error */
464 }
465 if (card->release_completion)
466 complete(card->release_completion);
467 kfree(card);
468 return 0;
469}
470
471int snd_card_free_when_closed(struct snd_card *card)
472{
473 int ret = snd_card_disconnect(card);
474 if (ret)
475 return ret;
476 put_device(&card->card_dev);
477 return 0;
478}
479EXPORT_SYMBOL(snd_card_free_when_closed);
480
481int snd_card_free(struct snd_card *card)
482{
483 struct completion released;
484 int ret;
485
486 init_completion(&released);
487 card->release_completion = &released;
488 ret = snd_card_free_when_closed(card);
489 if (ret)
490 return ret;
491 /* wait, until all devices are ready for the free operation */
492 wait_for_completion(&released);
493 return 0;
494}
495EXPORT_SYMBOL(snd_card_free);
496
497/* retrieve the last word of shortname or longname */
498static const char *retrieve_id_from_card_name(const char *name)
499{
500 const char *spos = name;
501
502 while (*name) {
503 if (isspace(*name) && isalnum(name[1]))
504 spos = name + 1;
505 name++;
506 }
507 return spos;
508}
509
510/* return true if the given id string doesn't conflict any other card ids */
511static bool card_id_ok(struct snd_card *card, const char *id)
512{
513 int i;
514 if (!snd_info_check_reserved_words(id))
515 return false;
516 for (i = 0; i < snd_ecards_limit; i++) {
517 if (snd_cards[i] && snd_cards[i] != card &&
518 !strcmp(snd_cards[i]->id, id))
519 return false;
520 }
521 return true;
522}
523
524/* copy to card->id only with valid letters from nid */
525static void copy_valid_id_string(struct snd_card *card, const char *src,
526 const char *nid)
527{
528 char *id = card->id;
529
530 while (*nid && !isalnum(*nid))
531 nid++;
532 if (isdigit(*nid))
533 *id++ = isalpha(*src) ? *src : 'D';
534 while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
535 if (isalnum(*nid))
536 *id++ = *nid;
537 nid++;
538 }
539 *id = 0;
540}
541
542/* Set card->id from the given string
543 * If the string conflicts with other ids, add a suffix to make it unique.
544 */
545static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
546 const char *nid)
547{
548 int len, loops;
549 bool is_default = false;
550 char *id;
551
552 copy_valid_id_string(card, src, nid);
553 id = card->id;
554
555 again:
556 /* use "Default" for obviously invalid strings
557 * ("card" conflicts with proc directories)
558 */
559 if (!*id || !strncmp(id, "card", 4)) {
560 strcpy(id, "Default");
561 is_default = true;
562 }
563
564 len = strlen(id);
565 for (loops = 0; loops < SNDRV_CARDS; loops++) {
566 char *spos;
567 char sfxstr[5]; /* "_012" */
568 int sfxlen;
569
570 if (card_id_ok(card, id))
571 return; /* OK */
572
573 /* Add _XYZ suffix */
574 sprintf(sfxstr, "_%X", loops + 1);
575 sfxlen = strlen(sfxstr);
576 if (len + sfxlen >= sizeof(card->id))
577 spos = id + sizeof(card->id) - sfxlen - 1;
578 else
579 spos = id + len;
580 strcpy(spos, sfxstr);
581 }
582 /* fallback to the default id */
583 if (!is_default) {
584 *id = 0;
585 goto again;
586 }
587 /* last resort... */
588 dev_err(card->dev, "unable to set card id (%s)\n", id);
589 if (card->proc_root->name)
590 strlcpy(card->id, card->proc_root->name, sizeof(card->id));
591}
592
593/**
594 * snd_card_set_id - set card identification name
595 * @card: soundcard structure
596 * @nid: new identification string
597 *
598 * This function sets the card identification and checks for name
599 * collisions.
600 */
601void snd_card_set_id(struct snd_card *card, const char *nid)
602{
603 /* check if user specified own card->id */
604 if (card->id[0] != '\0')
605 return;
606 mutex_lock(&snd_card_mutex);
607 snd_card_set_id_no_lock(card, nid, nid);
608 mutex_unlock(&snd_card_mutex);
609}
610EXPORT_SYMBOL(snd_card_set_id);
611
612static ssize_t
613card_id_show_attr(struct device *dev,
614 struct device_attribute *attr, char *buf)
615{
616 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
617 return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
618}
619
620static ssize_t
621card_id_store_attr(struct device *dev, struct device_attribute *attr,
622 const char *buf, size_t count)
623{
624 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
625 char buf1[sizeof(card->id)];
626 size_t copy = count > sizeof(card->id) - 1 ?
627 sizeof(card->id) - 1 : count;
628 size_t idx;
629 int c;
630
631 for (idx = 0; idx < copy; idx++) {
632 c = buf[idx];
633 if (!isalnum(c) && c != '_' && c != '-')
634 return -EINVAL;
635 }
636 memcpy(buf1, buf, copy);
637 buf1[copy] = '\0';
638 mutex_lock(&snd_card_mutex);
639 if (!card_id_ok(NULL, buf1)) {
640 mutex_unlock(&snd_card_mutex);
641 return -EEXIST;
642 }
643 strcpy(card->id, buf1);
644 snd_info_card_id_change(card);
645 mutex_unlock(&snd_card_mutex);
646
647 return count;
648}
649
650static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
651
652static ssize_t
653card_number_show_attr(struct device *dev,
654 struct device_attribute *attr, char *buf)
655{
656 struct snd_card *card = container_of(dev, struct snd_card, card_dev);
657 return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
658}
659
660static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
661
662static struct attribute *card_dev_attrs[] = {
663 &dev_attr_id.attr,
664 &dev_attr_number.attr,
665 NULL
666};
667
668static struct attribute_group card_dev_attr_group = {
669 .attrs = card_dev_attrs,
670};
671
672static const struct attribute_group *card_dev_attr_groups[] = {
673 &card_dev_attr_group,
674 NULL
675};
676
677/**
678 * snd_card_register - register the soundcard
679 * @card: soundcard structure
680 *
681 * This function registers all the devices assigned to the soundcard.
682 * Until calling this, the ALSA control interface is blocked from the
683 * external accesses. Thus, you should call this function at the end
684 * of the initialization of the card.
685 *
686 * Return: Zero otherwise a negative error code if the registration failed.
687 */
688int snd_card_register(struct snd_card *card)
689{
690 int err;
691
692 if (snd_BUG_ON(!card))
693 return -EINVAL;
694
695 if (!card->registered) {
696 err = device_add(&card->card_dev);
697 if (err < 0)
698 return err;
699 card->registered = true;
700 }
701
702 if ((err = snd_device_register_all(card)) < 0)
703 return err;
704 mutex_lock(&snd_card_mutex);
705 if (snd_cards[card->number]) {
706 /* already registered */
707 mutex_unlock(&snd_card_mutex);
708 return 0;
709 }
710 if (*card->id) {
711 /* make a unique id name from the given string */
712 char tmpid[sizeof(card->id)];
713 memcpy(tmpid, card->id, sizeof(card->id));
714 snd_card_set_id_no_lock(card, tmpid, tmpid);
715 } else {
716 /* create an id from either shortname or longname */
717 const char *src;
718 src = *card->shortname ? card->shortname : card->longname;
719 snd_card_set_id_no_lock(card, src,
720 retrieve_id_from_card_name(src));
721 }
722 snd_cards[card->number] = card;
723 mutex_unlock(&snd_card_mutex);
724 init_info_for_card(card);
725#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
726 if (snd_mixer_oss_notify_callback)
727 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
728#endif
729 return 0;
730}
731
732EXPORT_SYMBOL(snd_card_register);
733
734#ifdef CONFIG_PROC_FS
735static struct snd_info_entry *snd_card_info_entry;
736
737static void snd_card_info_read(struct snd_info_entry *entry,
738 struct snd_info_buffer *buffer)
739{
740 int idx, count;
741 struct snd_card *card;
742
743 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
744 mutex_lock(&snd_card_mutex);
745 if ((card = snd_cards[idx]) != NULL) {
746 count++;
747 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
748 idx,
749 card->id,
750 card->driver,
751 card->shortname);
752 snd_iprintf(buffer, " %s\n",
753 card->longname);
754 }
755 mutex_unlock(&snd_card_mutex);
756 }
757 if (!count)
758 snd_iprintf(buffer, "--- no soundcards ---\n");
759}
760
761#ifdef CONFIG_SND_OSSEMUL
762
763void snd_card_info_read_oss(struct snd_info_buffer *buffer)
764{
765 int idx, count;
766 struct snd_card *card;
767
768 for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
769 mutex_lock(&snd_card_mutex);
770 if ((card = snd_cards[idx]) != NULL) {
771 count++;
772 snd_iprintf(buffer, "%s\n", card->longname);
773 }
774 mutex_unlock(&snd_card_mutex);
775 }
776 if (!count) {
777 snd_iprintf(buffer, "--- no soundcards ---\n");
778 }
779}
780
781#endif
782
783#ifdef MODULE
784static struct snd_info_entry *snd_card_module_info_entry;
785static void snd_card_module_info_read(struct snd_info_entry *entry,
786 struct snd_info_buffer *buffer)
787{
788 int idx;
789 struct snd_card *card;
790
791 for (idx = 0; idx < SNDRV_CARDS; idx++) {
792 mutex_lock(&snd_card_mutex);
793 if ((card = snd_cards[idx]) != NULL)
794 snd_iprintf(buffer, "%2i %s\n",
795 idx, card->module->name);
796 mutex_unlock(&snd_card_mutex);
797 }
798}
799#endif
800
801int __init snd_card_info_init(void)
802{
803 struct snd_info_entry *entry;
804
805 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
806 if (! entry)
807 return -ENOMEM;
808 entry->c.text.read = snd_card_info_read;
809 if (snd_info_register(entry) < 0) {
810 snd_info_free_entry(entry);
811 return -ENOMEM;
812 }
813 snd_card_info_entry = entry;
814
815#ifdef MODULE
816 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
817 if (entry) {
818 entry->c.text.read = snd_card_module_info_read;
819 if (snd_info_register(entry) < 0)
820 snd_info_free_entry(entry);
821 else
822 snd_card_module_info_entry = entry;
823 }
824#endif
825
826 return 0;
827}
828
829int __exit snd_card_info_done(void)
830{
831 snd_info_free_entry(snd_card_info_entry);
832#ifdef MODULE
833 snd_info_free_entry(snd_card_module_info_entry);
834#endif
835 return 0;
836}
837
838#endif /* CONFIG_PROC_FS */
839
840/**
841 * snd_component_add - add a component string
842 * @card: soundcard structure
843 * @component: the component id string
844 *
845 * This function adds the component id string to the supported list.
846 * The component can be referred from the alsa-lib.
847 *
848 * Return: Zero otherwise a negative error code.
849 */
850
851int snd_component_add(struct snd_card *card, const char *component)
852{
853 char *ptr;
854 int len = strlen(component);
855
856 ptr = strstr(card->components, component);
857 if (ptr != NULL) {
858 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
859 return 1;
860 }
861 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
862 snd_BUG();
863 return -ENOMEM;
864 }
865 if (card->components[0] != '\0')
866 strcat(card->components, " ");
867 strcat(card->components, component);
868 return 0;
869}
870
871EXPORT_SYMBOL(snd_component_add);
872
873/**
874 * snd_card_file_add - add the file to the file list of the card
875 * @card: soundcard structure
876 * @file: file pointer
877 *
878 * This function adds the file to the file linked-list of the card.
879 * This linked-list is used to keep tracking the connection state,
880 * and to avoid the release of busy resources by hotplug.
881 *
882 * Return: zero or a negative error code.
883 */
884int snd_card_file_add(struct snd_card *card, struct file *file)
885{
886 struct snd_monitor_file *mfile;
887
888 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
889 if (mfile == NULL)
890 return -ENOMEM;
891 mfile->file = file;
892 mfile->disconnected_f_op = NULL;
893 INIT_LIST_HEAD(&mfile->shutdown_list);
894 spin_lock(&card->files_lock);
895 if (card->shutdown) {
896 spin_unlock(&card->files_lock);
897 kfree(mfile);
898 return -ENODEV;
899 }
900 list_add(&mfile->list, &card->files_list);
901 get_device(&card->card_dev);
902 spin_unlock(&card->files_lock);
903 return 0;
904}
905
906EXPORT_SYMBOL(snd_card_file_add);
907
908/**
909 * snd_card_file_remove - remove the file from the file list
910 * @card: soundcard structure
911 * @file: file pointer
912 *
913 * This function removes the file formerly added to the card via
914 * snd_card_file_add() function.
915 * If all files are removed and snd_card_free_when_closed() was
916 * called beforehand, it processes the pending release of
917 * resources.
918 *
919 * Return: Zero or a negative error code.
920 */
921int snd_card_file_remove(struct snd_card *card, struct file *file)
922{
923 struct snd_monitor_file *mfile, *found = NULL;
924
925 spin_lock(&card->files_lock);
926 list_for_each_entry(mfile, &card->files_list, list) {
927 if (mfile->file == file) {
928 list_del(&mfile->list);
929 spin_lock(&shutdown_lock);
930 list_del(&mfile->shutdown_list);
931 spin_unlock(&shutdown_lock);
932 if (mfile->disconnected_f_op)
933 fops_put(mfile->disconnected_f_op);
934 found = mfile;
935 break;
936 }
937 }
938 spin_unlock(&card->files_lock);
939 if (!found) {
940 dev_err(card->dev, "card file remove problem (%p)\n", file);
941 return -ENOENT;
942 }
943 kfree(found);
944 put_device(&card->card_dev);
945 return 0;
946}
947
948EXPORT_SYMBOL(snd_card_file_remove);
949
950#ifdef CONFIG_PM
951/**
952 * snd_power_wait - wait until the power-state is changed.
953 * @card: soundcard structure
954 * @power_state: expected power state
955 *
956 * Waits until the power-state is changed.
957 *
958 * Return: Zero if successful, or a negative error code.
959 *
960 * Note: the power lock must be active before call.
961 */
962int snd_power_wait(struct snd_card *card, unsigned int power_state)
963{
964 wait_queue_t wait;
965 int result = 0;
966
967 /* fastpath */
968 if (snd_power_get_state(card) == power_state)
969 return 0;
970 init_waitqueue_entry(&wait, current);
971 add_wait_queue(&card->power_sleep, &wait);
972 while (1) {
973 if (card->shutdown) {
974 result = -ENODEV;
975 break;
976 }
977 if (snd_power_get_state(card) == power_state)
978 break;
979 set_current_state(TASK_UNINTERRUPTIBLE);
980 snd_power_unlock(card);
981 schedule_timeout(30 * HZ);
982 snd_power_lock(card);
983 }
984 remove_wait_queue(&card->power_sleep, &wait);
985 return result;
986}
987
988EXPORT_SYMBOL(snd_power_wait);
989#endif /* CONFIG_PM */