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Merge remote-tracking branch 'asoc/topic/wm8960' into asoc-next
[linux-2.6-block.git] / sound / core / info.c
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1/*
2 * Information interface for ALSA driver
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/time.h>
24#include <linux/mm.h>
25#include <linux/slab.h>
26#include <linux/string.h>
27#include <linux/module.h>
28#include <sound/core.h>
29#include <sound/minors.h>
30#include <sound/info.h>
31#include <linux/utsname.h>
32#include <linux/proc_fs.h>
33#include <linux/mutex.h>
34#include <stdarg.h>
35
36int snd_info_check_reserved_words(const char *str)
37{
38 static char *reserved[] =
39 {
40 "version",
41 "meminfo",
42 "memdebug",
43 "detect",
44 "devices",
45 "oss",
46 "cards",
47 "timers",
48 "synth",
49 "pcm",
50 "seq",
51 NULL
52 };
53 char **xstr = reserved;
54
55 while (*xstr) {
56 if (!strcmp(*xstr, str))
57 return 0;
58 xstr++;
59 }
60 if (!strncmp(str, "card", 4))
61 return 0;
62 return 1;
63}
64
65static DEFINE_MUTEX(info_mutex);
66
67struct snd_info_private_data {
68 struct snd_info_buffer *rbuffer;
69 struct snd_info_buffer *wbuffer;
70 struct snd_info_entry *entry;
71 void *file_private_data;
72};
73
74static int snd_info_version_init(void);
75static void snd_info_disconnect(struct snd_info_entry *entry);
76
77/*
78
79 */
80
81static struct snd_info_entry *snd_proc_root;
82struct snd_info_entry *snd_seq_root;
83EXPORT_SYMBOL(snd_seq_root);
84
85#ifdef CONFIG_SND_OSSEMUL
86struct snd_info_entry *snd_oss_root;
87#endif
88
89static int alloc_info_private(struct snd_info_entry *entry,
90 struct snd_info_private_data **ret)
91{
92 struct snd_info_private_data *data;
93
94 if (!entry || !entry->p)
95 return -ENODEV;
96 if (!try_module_get(entry->module))
97 return -EFAULT;
98 data = kzalloc(sizeof(*data), GFP_KERNEL);
99 if (!data) {
100 module_put(entry->module);
101 return -ENOMEM;
102 }
103 data->entry = entry;
104 *ret = data;
105 return 0;
106}
107
108static bool valid_pos(loff_t pos, size_t count)
109{
110 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
111 return false;
112 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
113 return false;
114 return true;
115}
116
117/*
118 * file ops for binary proc files
119 */
120static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
121{
122 struct snd_info_private_data *data;
123 struct snd_info_entry *entry;
124 loff_t ret = -EINVAL, size;
125
126 data = file->private_data;
127 entry = data->entry;
128 mutex_lock(&entry->access);
129 if (entry->c.ops->llseek) {
130 offset = entry->c.ops->llseek(entry,
131 data->file_private_data,
132 file, offset, orig);
133 goto out;
134 }
135
136 size = entry->size;
137 switch (orig) {
138 case SEEK_SET:
139 break;
140 case SEEK_CUR:
141 offset += file->f_pos;
142 break;
143 case SEEK_END:
144 if (!size)
145 goto out;
146 offset += size;
147 break;
148 default:
149 goto out;
150 }
151 if (offset < 0)
152 goto out;
153 if (size && offset > size)
154 offset = size;
155 file->f_pos = offset;
156 ret = offset;
157 out:
158 mutex_unlock(&entry->access);
159 return ret;
160}
161
162static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
163 size_t count, loff_t * offset)
164{
165 struct snd_info_private_data *data = file->private_data;
166 struct snd_info_entry *entry = data->entry;
167 size_t size;
168 loff_t pos;
169
170 pos = *offset;
171 if (!valid_pos(pos, count))
172 return -EIO;
173 if (pos >= entry->size)
174 return 0;
175 size = entry->size - pos;
176 size = min(count, size);
177 size = entry->c.ops->read(entry, data->file_private_data,
178 file, buffer, size, pos);
179 if ((ssize_t) size > 0)
180 *offset = pos + size;
181 return size;
182}
183
184static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
185 size_t count, loff_t * offset)
186{
187 struct snd_info_private_data *data = file->private_data;
188 struct snd_info_entry *entry = data->entry;
189 ssize_t size = 0;
190 loff_t pos;
191
192 pos = *offset;
193 if (!valid_pos(pos, count))
194 return -EIO;
195 if (count > 0) {
196 size_t maxsize = entry->size - pos;
197 count = min(count, maxsize);
198 size = entry->c.ops->write(entry, data->file_private_data,
199 file, buffer, count, pos);
200 }
201 if (size > 0)
202 *offset = pos + size;
203 return size;
204}
205
206static unsigned int snd_info_entry_poll(struct file *file, poll_table *wait)
207{
208 struct snd_info_private_data *data = file->private_data;
209 struct snd_info_entry *entry = data->entry;
210 unsigned int mask = 0;
211
212 if (entry->c.ops->poll)
213 return entry->c.ops->poll(entry,
214 data->file_private_data,
215 file, wait);
216 if (entry->c.ops->read)
217 mask |= POLLIN | POLLRDNORM;
218 if (entry->c.ops->write)
219 mask |= POLLOUT | POLLWRNORM;
220 return mask;
221}
222
223static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
224 unsigned long arg)
225{
226 struct snd_info_private_data *data = file->private_data;
227 struct snd_info_entry *entry = data->entry;
228
229 if (!entry->c.ops->ioctl)
230 return -ENOTTY;
231 return entry->c.ops->ioctl(entry, data->file_private_data,
232 file, cmd, arg);
233}
234
235static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
236{
237 struct inode *inode = file_inode(file);
238 struct snd_info_private_data *data;
239 struct snd_info_entry *entry;
240
241 data = file->private_data;
242 if (data == NULL)
243 return 0;
244 entry = data->entry;
245 if (!entry->c.ops->mmap)
246 return -ENXIO;
247 return entry->c.ops->mmap(entry, data->file_private_data,
248 inode, file, vma);
249}
250
251static int snd_info_entry_open(struct inode *inode, struct file *file)
252{
253 struct snd_info_entry *entry = PDE_DATA(inode);
254 struct snd_info_private_data *data;
255 int mode, err;
256
257 mutex_lock(&info_mutex);
258 err = alloc_info_private(entry, &data);
259 if (err < 0)
260 goto unlock;
261
262 mode = file->f_flags & O_ACCMODE;
263 if (((mode == O_RDONLY || mode == O_RDWR) && !entry->c.ops->read) ||
264 ((mode == O_WRONLY || mode == O_RDWR) && !entry->c.ops->write)) {
265 err = -ENODEV;
266 goto error;
267 }
268
269 if (entry->c.ops->open) {
270 err = entry->c.ops->open(entry, mode, &data->file_private_data);
271 if (err < 0)
272 goto error;
273 }
274
275 file->private_data = data;
276 mutex_unlock(&info_mutex);
277 return 0;
278
279 error:
280 kfree(data);
281 module_put(entry->module);
282 unlock:
283 mutex_unlock(&info_mutex);
284 return err;
285}
286
287static int snd_info_entry_release(struct inode *inode, struct file *file)
288{
289 struct snd_info_private_data *data = file->private_data;
290 struct snd_info_entry *entry = data->entry;
291
292 if (entry->c.ops->release)
293 entry->c.ops->release(entry, file->f_flags & O_ACCMODE,
294 data->file_private_data);
295 module_put(entry->module);
296 kfree(data);
297 return 0;
298}
299
300static const struct file_operations snd_info_entry_operations =
301{
302 .owner = THIS_MODULE,
303 .llseek = snd_info_entry_llseek,
304 .read = snd_info_entry_read,
305 .write = snd_info_entry_write,
306 .poll = snd_info_entry_poll,
307 .unlocked_ioctl = snd_info_entry_ioctl,
308 .mmap = snd_info_entry_mmap,
309 .open = snd_info_entry_open,
310 .release = snd_info_entry_release,
311};
312
313/*
314 * file ops for text proc files
315 */
316static ssize_t snd_info_text_entry_write(struct file *file,
317 const char __user *buffer,
318 size_t count, loff_t *offset)
319{
320 struct seq_file *m = file->private_data;
321 struct snd_info_private_data *data = m->private;
322 struct snd_info_entry *entry = data->entry;
323 struct snd_info_buffer *buf;
324 loff_t pos;
325 size_t next;
326 int err = 0;
327
328 pos = *offset;
329 if (!valid_pos(pos, count))
330 return -EIO;
331 next = pos + count;
332 mutex_lock(&entry->access);
333 buf = data->wbuffer;
334 if (!buf) {
335 data->wbuffer = buf = kzalloc(sizeof(*buf), GFP_KERNEL);
336 if (!buf) {
337 err = -ENOMEM;
338 goto error;
339 }
340 }
341 if (next > buf->len) {
342 char *nbuf = krealloc(buf->buffer, PAGE_ALIGN(next),
343 GFP_KERNEL | __GFP_ZERO);
344 if (!nbuf) {
345 err = -ENOMEM;
346 goto error;
347 }
348 buf->buffer = nbuf;
349 buf->len = PAGE_ALIGN(next);
350 }
351 if (copy_from_user(buf->buffer + pos, buffer, count)) {
352 err = -EFAULT;
353 goto error;
354 }
355 buf->size = next;
356 error:
357 mutex_unlock(&entry->access);
358 if (err < 0)
359 return err;
360 *offset = next;
361 return count;
362}
363
364static int snd_info_seq_show(struct seq_file *seq, void *p)
365{
366 struct snd_info_private_data *data = seq->private;
367 struct snd_info_entry *entry = data->entry;
368
369 if (entry->c.text.read) {
370 data->rbuffer->buffer = (char *)seq; /* XXX hack! */
371 entry->c.text.read(entry, data->rbuffer);
372 }
373 return 0;
374}
375
376static int snd_info_text_entry_open(struct inode *inode, struct file *file)
377{
378 struct snd_info_entry *entry = PDE_DATA(inode);
379 struct snd_info_private_data *data;
380 int err;
381
382 mutex_lock(&info_mutex);
383 err = alloc_info_private(entry, &data);
384 if (err < 0)
385 goto unlock;
386
387 data->rbuffer = kzalloc(sizeof(*data->rbuffer), GFP_KERNEL);
388 if (!data->rbuffer) {
389 err = -ENOMEM;
390 goto error;
391 }
392 if (entry->size)
393 err = single_open_size(file, snd_info_seq_show, data,
394 entry->size);
395 else
396 err = single_open(file, snd_info_seq_show, data);
397 if (err < 0)
398 goto error;
399 mutex_unlock(&info_mutex);
400 return 0;
401
402 error:
403 kfree(data->rbuffer);
404 kfree(data);
405 module_put(entry->module);
406 unlock:
407 mutex_unlock(&info_mutex);
408 return err;
409}
410
411static int snd_info_text_entry_release(struct inode *inode, struct file *file)
412{
413 struct seq_file *m = file->private_data;
414 struct snd_info_private_data *data = m->private;
415 struct snd_info_entry *entry = data->entry;
416
417 if (data->wbuffer && entry->c.text.write)
418 entry->c.text.write(entry, data->wbuffer);
419
420 single_release(inode, file);
421 kfree(data->rbuffer);
422 if (data->wbuffer) {
423 kfree(data->wbuffer->buffer);
424 kfree(data->wbuffer);
425 }
426
427 module_put(entry->module);
428 kfree(data);
429 return 0;
430}
431
432static const struct file_operations snd_info_text_entry_ops =
433{
434 .owner = THIS_MODULE,
435 .open = snd_info_text_entry_open,
436 .release = snd_info_text_entry_release,
437 .write = snd_info_text_entry_write,
438 .llseek = seq_lseek,
439 .read = seq_read,
440};
441
442static struct snd_info_entry *create_subdir(struct module *mod,
443 const char *name)
444{
445 struct snd_info_entry *entry;
446
447 entry = snd_info_create_module_entry(mod, name, NULL);
448 if (!entry)
449 return NULL;
450 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
451 if (snd_info_register(entry) < 0) {
452 snd_info_free_entry(entry);
453 return NULL;
454 }
455 return entry;
456}
457
458static struct snd_info_entry *
459snd_info_create_entry(const char *name, struct snd_info_entry *parent);
460
461int __init snd_info_init(void)
462{
463 snd_proc_root = snd_info_create_entry("asound", NULL);
464 if (!snd_proc_root)
465 return -ENOMEM;
466 snd_proc_root->mode = S_IFDIR | S_IRUGO | S_IXUGO;
467 snd_proc_root->p = proc_mkdir("asound", NULL);
468 if (!snd_proc_root->p)
469 goto error;
470#ifdef CONFIG_SND_OSSEMUL
471 snd_oss_root = create_subdir(THIS_MODULE, "oss");
472 if (!snd_oss_root)
473 goto error;
474#endif
475#if IS_ENABLED(CONFIG_SND_SEQUENCER)
476 snd_seq_root = create_subdir(THIS_MODULE, "seq");
477 if (!snd_seq_root)
478 goto error;
479#endif
480 if (snd_info_version_init() < 0 ||
481 snd_minor_info_init() < 0 ||
482 snd_minor_info_oss_init() < 0 ||
483 snd_card_info_init() < 0 ||
484 snd_info_minor_register() < 0)
485 goto error;
486 return 0;
487
488 error:
489 snd_info_free_entry(snd_proc_root);
490 return -ENOMEM;
491}
492
493int __exit snd_info_done(void)
494{
495 snd_info_free_entry(snd_proc_root);
496 return 0;
497}
498
499/*
500 * create a card proc file
501 * called from init.c
502 */
503int snd_info_card_create(struct snd_card *card)
504{
505 char str[8];
506 struct snd_info_entry *entry;
507
508 if (snd_BUG_ON(!card))
509 return -ENXIO;
510
511 sprintf(str, "card%i", card->number);
512 entry = create_subdir(card->module, str);
513 if (!entry)
514 return -ENOMEM;
515 card->proc_root = entry;
516 return 0;
517}
518
519/* register all pending info entries */
520static int snd_info_register_recursive(struct snd_info_entry *entry)
521{
522 struct snd_info_entry *p;
523 int err;
524
525 if (!entry->p) {
526 err = snd_info_register(entry);
527 if (err < 0)
528 return err;
529 }
530
531 list_for_each_entry(p, &entry->children, list) {
532 err = snd_info_register_recursive(p);
533 if (err < 0)
534 return err;
535 }
536
537 return 0;
538}
539
540/*
541 * register the card proc file
542 * called from init.c
543 * can be called multiple times for reinitialization
544 */
545int snd_info_card_register(struct snd_card *card)
546{
547 struct proc_dir_entry *p;
548 int err;
549
550 if (snd_BUG_ON(!card))
551 return -ENXIO;
552
553 err = snd_info_register_recursive(card->proc_root);
554 if (err < 0)
555 return err;
556
557 if (!strcmp(card->id, card->proc_root->name))
558 return 0;
559
560 if (card->proc_root_link)
561 return 0;
562 p = proc_symlink(card->id, snd_proc_root->p, card->proc_root->name);
563 if (!p)
564 return -ENOMEM;
565 card->proc_root_link = p;
566 return 0;
567}
568
569/*
570 * called on card->id change
571 */
572void snd_info_card_id_change(struct snd_card *card)
573{
574 mutex_lock(&info_mutex);
575 if (card->proc_root_link) {
576 proc_remove(card->proc_root_link);
577 card->proc_root_link = NULL;
578 }
579 if (strcmp(card->id, card->proc_root->name))
580 card->proc_root_link = proc_symlink(card->id,
581 snd_proc_root->p,
582 card->proc_root->name);
583 mutex_unlock(&info_mutex);
584}
585
586/*
587 * de-register the card proc file
588 * called from init.c
589 */
590void snd_info_card_disconnect(struct snd_card *card)
591{
592 if (!card)
593 return;
594 mutex_lock(&info_mutex);
595 proc_remove(card->proc_root_link);
596 card->proc_root_link = NULL;
597 if (card->proc_root)
598 snd_info_disconnect(card->proc_root);
599 mutex_unlock(&info_mutex);
600}
601
602/*
603 * release the card proc file resources
604 * called from init.c
605 */
606int snd_info_card_free(struct snd_card *card)
607{
608 if (!card)
609 return 0;
610 snd_info_free_entry(card->proc_root);
611 card->proc_root = NULL;
612 return 0;
613}
614
615
616/**
617 * snd_info_get_line - read one line from the procfs buffer
618 * @buffer: the procfs buffer
619 * @line: the buffer to store
620 * @len: the max. buffer size
621 *
622 * Reads one line from the buffer and stores the string.
623 *
624 * Return: Zero if successful, or 1 if error or EOF.
625 */
626int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
627{
628 int c = -1;
629
630 if (snd_BUG_ON(!buffer || !buffer->buffer))
631 return 1;
632 if (len <= 0 || buffer->stop || buffer->error)
633 return 1;
634 while (!buffer->stop) {
635 c = buffer->buffer[buffer->curr++];
636 if (buffer->curr >= buffer->size)
637 buffer->stop = 1;
638 if (c == '\n')
639 break;
640 if (len > 1) {
641 len--;
642 *line++ = c;
643 }
644 }
645 *line = '\0';
646 return 0;
647}
648
649EXPORT_SYMBOL(snd_info_get_line);
650
651/**
652 * snd_info_get_str - parse a string token
653 * @dest: the buffer to store the string token
654 * @src: the original string
655 * @len: the max. length of token - 1
656 *
657 * Parses the original string and copy a token to the given
658 * string buffer.
659 *
660 * Return: The updated pointer of the original string so that
661 * it can be used for the next call.
662 */
663const char *snd_info_get_str(char *dest, const char *src, int len)
664{
665 int c;
666
667 while (*src == ' ' || *src == '\t')
668 src++;
669 if (*src == '"' || *src == '\'') {
670 c = *src++;
671 while (--len > 0 && *src && *src != c) {
672 *dest++ = *src++;
673 }
674 if (*src == c)
675 src++;
676 } else {
677 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
678 *dest++ = *src++;
679 }
680 }
681 *dest = 0;
682 while (*src == ' ' || *src == '\t')
683 src++;
684 return src;
685}
686
687EXPORT_SYMBOL(snd_info_get_str);
688
689/*
690 * snd_info_create_entry - create an info entry
691 * @name: the proc file name
692 * @parent: the parent directory
693 *
694 * Creates an info entry with the given file name and initializes as
695 * the default state.
696 *
697 * Usually called from other functions such as
698 * snd_info_create_card_entry().
699 *
700 * Return: The pointer of the new instance, or %NULL on failure.
701 */
702static struct snd_info_entry *
703snd_info_create_entry(const char *name, struct snd_info_entry *parent)
704{
705 struct snd_info_entry *entry;
706 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
707 if (entry == NULL)
708 return NULL;
709 entry->name = kstrdup(name, GFP_KERNEL);
710 if (entry->name == NULL) {
711 kfree(entry);
712 return NULL;
713 }
714 entry->mode = S_IFREG | S_IRUGO;
715 entry->content = SNDRV_INFO_CONTENT_TEXT;
716 mutex_init(&entry->access);
717 INIT_LIST_HEAD(&entry->children);
718 INIT_LIST_HEAD(&entry->list);
719 entry->parent = parent;
720 if (parent)
721 list_add_tail(&entry->list, &parent->children);
722 return entry;
723}
724
725/**
726 * snd_info_create_module_entry - create an info entry for the given module
727 * @module: the module pointer
728 * @name: the file name
729 * @parent: the parent directory
730 *
731 * Creates a new info entry and assigns it to the given module.
732 *
733 * Return: The pointer of the new instance, or %NULL on failure.
734 */
735struct snd_info_entry *snd_info_create_module_entry(struct module * module,
736 const char *name,
737 struct snd_info_entry *parent)
738{
739 struct snd_info_entry *entry = snd_info_create_entry(name, parent);
740 if (entry)
741 entry->module = module;
742 return entry;
743}
744
745EXPORT_SYMBOL(snd_info_create_module_entry);
746
747/**
748 * snd_info_create_card_entry - create an info entry for the given card
749 * @card: the card instance
750 * @name: the file name
751 * @parent: the parent directory
752 *
753 * Creates a new info entry and assigns it to the given card.
754 *
755 * Return: The pointer of the new instance, or %NULL on failure.
756 */
757struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
758 const char *name,
759 struct snd_info_entry * parent)
760{
761 struct snd_info_entry *entry = snd_info_create_entry(name, parent);
762 if (entry) {
763 entry->module = card->module;
764 entry->card = card;
765 }
766 return entry;
767}
768
769EXPORT_SYMBOL(snd_info_create_card_entry);
770
771static void snd_info_disconnect(struct snd_info_entry *entry)
772{
773 struct snd_info_entry *p;
774
775 if (!entry->p)
776 return;
777 list_for_each_entry(p, &entry->children, list)
778 snd_info_disconnect(p);
779 proc_remove(entry->p);
780 entry->p = NULL;
781}
782
783/**
784 * snd_info_free_entry - release the info entry
785 * @entry: the info entry
786 *
787 * Releases the info entry.
788 */
789void snd_info_free_entry(struct snd_info_entry * entry)
790{
791 struct snd_info_entry *p, *n;
792
793 if (!entry)
794 return;
795 if (entry->p) {
796 mutex_lock(&info_mutex);
797 snd_info_disconnect(entry);
798 mutex_unlock(&info_mutex);
799 }
800
801 /* free all children at first */
802 list_for_each_entry_safe(p, n, &entry->children, list)
803 snd_info_free_entry(p);
804
805 list_del(&entry->list);
806 kfree(entry->name);
807 if (entry->private_free)
808 entry->private_free(entry);
809 kfree(entry);
810}
811
812EXPORT_SYMBOL(snd_info_free_entry);
813
814/**
815 * snd_info_register - register the info entry
816 * @entry: the info entry
817 *
818 * Registers the proc info entry.
819 *
820 * Return: Zero if successful, or a negative error code on failure.
821 */
822int snd_info_register(struct snd_info_entry * entry)
823{
824 struct proc_dir_entry *root, *p = NULL;
825
826 if (snd_BUG_ON(!entry))
827 return -ENXIO;
828 root = entry->parent == NULL ? snd_proc_root->p : entry->parent->p;
829 mutex_lock(&info_mutex);
830 if (S_ISDIR(entry->mode)) {
831 p = proc_mkdir_mode(entry->name, entry->mode, root);
832 if (!p) {
833 mutex_unlock(&info_mutex);
834 return -ENOMEM;
835 }
836 } else {
837 const struct file_operations *ops;
838 if (entry->content == SNDRV_INFO_CONTENT_DATA)
839 ops = &snd_info_entry_operations;
840 else
841 ops = &snd_info_text_entry_ops;
842 p = proc_create_data(entry->name, entry->mode, root,
843 ops, entry);
844 if (!p) {
845 mutex_unlock(&info_mutex);
846 return -ENOMEM;
847 }
848 proc_set_size(p, entry->size);
849 }
850 entry->p = p;
851 mutex_unlock(&info_mutex);
852 return 0;
853}
854
855EXPORT_SYMBOL(snd_info_register);
856
857/*
858
859 */
860
861static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
862{
863 snd_iprintf(buffer,
864 "Advanced Linux Sound Architecture Driver Version k%s.\n",
865 init_utsname()->release);
866}
867
868static int __init snd_info_version_init(void)
869{
870 struct snd_info_entry *entry;
871
872 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
873 if (entry == NULL)
874 return -ENOMEM;
875 entry->c.text.read = snd_info_version_read;
876 return snd_info_register(entry); /* freed in error path */
877}
Linux 6.x block layer and io_uring tree(s)