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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Information interface for ALSA driver
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/init.h>
8#include <linux/time.h>
9#include <linux/mm.h>
10#include <linux/slab.h>
11#include <linux/string.h>
12#include <linux/module.h>
13#include <sound/core.h>
14#include <sound/minors.h>
15#include <sound/info.h>
16#include <linux/utsname.h>
17#include <linux/proc_fs.h>
18#include <linux/mutex.h>
19
20int snd_info_check_reserved_words(const char *str)
21{
22 static const char * const reserved[] =
23 {
24 "version",
25 "meminfo",
26 "memdebug",
27 "detect",
28 "devices",
29 "oss",
30 "cards",
31 "timers",
32 "synth",
33 "pcm",
34 "seq",
35 NULL
36 };
37 const char * const *xstr = reserved;
38
39 while (*xstr) {
40 if (!strcmp(*xstr, str))
41 return 0;
42 xstr++;
43 }
44 if (!strncmp(str, "card", 4))
45 return 0;
46 return 1;
47}
48
49static DEFINE_MUTEX(info_mutex);
50
51struct snd_info_private_data {
52 struct snd_info_buffer *rbuffer;
53 struct snd_info_buffer *wbuffer;
54 struct snd_info_entry *entry;
55 void *file_private_data;
56};
57
58static int snd_info_version_init(void);
59static void snd_info_disconnect(struct snd_info_entry *entry);
60
61/*
62
63 */
64
65static struct snd_info_entry *snd_proc_root;
66struct snd_info_entry *snd_seq_root;
67EXPORT_SYMBOL(snd_seq_root);
68
69#ifdef CONFIG_SND_OSSEMUL
70struct snd_info_entry *snd_oss_root;
71#endif
72
73static int alloc_info_private(struct snd_info_entry *entry,
74 struct snd_info_private_data **ret)
75{
76 struct snd_info_private_data *data;
77
78 if (!entry || !entry->p)
79 return -ENODEV;
80 if (!try_module_get(entry->module))
81 return -EFAULT;
82 data = kzalloc(sizeof(*data), GFP_KERNEL);
83 if (!data) {
84 module_put(entry->module);
85 return -ENOMEM;
86 }
87 data->entry = entry;
88 *ret = data;
89 return 0;
90}
91
92static bool valid_pos(loff_t pos, size_t count)
93{
94 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
95 return false;
96 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
97 return false;
98 return true;
99}
100
101/*
102 * file ops for binary proc files
103 */
104static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
105{
106 struct snd_info_private_data *data;
107 struct snd_info_entry *entry;
108 loff_t ret = -EINVAL, size;
109
110 data = file->private_data;
111 entry = data->entry;
112 mutex_lock(&entry->access);
113 if (entry->c.ops->llseek) {
114 ret = entry->c.ops->llseek(entry,
115 data->file_private_data,
116 file, offset, orig);
117 goto out;
118 }
119
120 size = entry->size;
121 switch (orig) {
122 case SEEK_SET:
123 break;
124 case SEEK_CUR:
125 offset += file->f_pos;
126 break;
127 case SEEK_END:
128 if (!size)
129 goto out;
130 offset += size;
131 break;
132 default:
133 goto out;
134 }
135 if (offset < 0)
136 goto out;
137 if (size && offset > size)
138 offset = size;
139 file->f_pos = offset;
140 ret = offset;
141 out:
142 mutex_unlock(&entry->access);
143 return ret;
144}
145
146static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
147 size_t count, loff_t * offset)
148{
149 struct snd_info_private_data *data = file->private_data;
150 struct snd_info_entry *entry = data->entry;
151 size_t size;
152 loff_t pos;
153
154 pos = *offset;
155 if (!valid_pos(pos, count))
156 return -EIO;
157 if (pos >= entry->size)
158 return 0;
159 size = entry->size - pos;
160 size = min(count, size);
161 size = entry->c.ops->read(entry, data->file_private_data,
162 file, buffer, size, pos);
163 if ((ssize_t) size > 0)
164 *offset = pos + size;
165 return size;
166}
167
168static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
169 size_t count, loff_t * offset)
170{
171 struct snd_info_private_data *data = file->private_data;
172 struct snd_info_entry *entry = data->entry;
173 ssize_t size = 0;
174 loff_t pos;
175
176 pos = *offset;
177 if (!valid_pos(pos, count))
178 return -EIO;
179 if (count > 0) {
180 size_t maxsize = entry->size - pos;
181 count = min(count, maxsize);
182 size = entry->c.ops->write(entry, data->file_private_data,
183 file, buffer, count, pos);
184 }
185 if (size > 0)
186 *offset = pos + size;
187 return size;
188}
189
190static __poll_t snd_info_entry_poll(struct file *file, poll_table *wait)
191{
192 struct snd_info_private_data *data = file->private_data;
193 struct snd_info_entry *entry = data->entry;
194 __poll_t mask = 0;
195
196 if (entry->c.ops->poll)
197 return entry->c.ops->poll(entry,
198 data->file_private_data,
199 file, wait);
200 if (entry->c.ops->read)
201 mask |= EPOLLIN | EPOLLRDNORM;
202 if (entry->c.ops->write)
203 mask |= EPOLLOUT | EPOLLWRNORM;
204 return mask;
205}
206
207static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
208 unsigned long arg)
209{
210 struct snd_info_private_data *data = file->private_data;
211 struct snd_info_entry *entry = data->entry;
212
213 if (!entry->c.ops->ioctl)
214 return -ENOTTY;
215 return entry->c.ops->ioctl(entry, data->file_private_data,
216 file, cmd, arg);
217}
218
219static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
220{
221 struct inode *inode = file_inode(file);
222 struct snd_info_private_data *data;
223 struct snd_info_entry *entry;
224
225 data = file->private_data;
226 if (data == NULL)
227 return 0;
228 entry = data->entry;
229 if (!entry->c.ops->mmap)
230 return -ENXIO;
231 return entry->c.ops->mmap(entry, data->file_private_data,
232 inode, file, vma);
233}
234
235static int snd_info_entry_open(struct inode *inode, struct file *file)
236{
237 struct snd_info_entry *entry = pde_data(inode);
238 struct snd_info_private_data *data;
239 int mode, err;
240
241 mutex_lock(&info_mutex);
242 err = alloc_info_private(entry, &data);
243 if (err < 0)
244 goto unlock;
245
246 mode = file->f_flags & O_ACCMODE;
247 if (((mode == O_RDONLY || mode == O_RDWR) && !entry->c.ops->read) ||
248 ((mode == O_WRONLY || mode == O_RDWR) && !entry->c.ops->write)) {
249 err = -ENODEV;
250 goto error;
251 }
252
253 if (entry->c.ops->open) {
254 err = entry->c.ops->open(entry, mode, &data->file_private_data);
255 if (err < 0)
256 goto error;
257 }
258
259 file->private_data = data;
260 mutex_unlock(&info_mutex);
261 return 0;
262
263 error:
264 kfree(data);
265 module_put(entry->module);
266 unlock:
267 mutex_unlock(&info_mutex);
268 return err;
269}
270
271static int snd_info_entry_release(struct inode *inode, struct file *file)
272{
273 struct snd_info_private_data *data = file->private_data;
274 struct snd_info_entry *entry = data->entry;
275
276 if (entry->c.ops->release)
277 entry->c.ops->release(entry, file->f_flags & O_ACCMODE,
278 data->file_private_data);
279 module_put(entry->module);
280 kfree(data);
281 return 0;
282}
283
284static const struct proc_ops snd_info_entry_operations =
285{
286 .proc_lseek = snd_info_entry_llseek,
287 .proc_read = snd_info_entry_read,
288 .proc_write = snd_info_entry_write,
289 .proc_poll = snd_info_entry_poll,
290 .proc_ioctl = snd_info_entry_ioctl,
291 .proc_mmap = snd_info_entry_mmap,
292 .proc_open = snd_info_entry_open,
293 .proc_release = snd_info_entry_release,
294};
295
296/*
297 * file ops for text proc files
298 */
299static ssize_t snd_info_text_entry_write(struct file *file,
300 const char __user *buffer,
301 size_t count, loff_t *offset)
302{
303 struct seq_file *m = file->private_data;
304 struct snd_info_private_data *data = m->private;
305 struct snd_info_entry *entry = data->entry;
306 struct snd_info_buffer *buf;
307 loff_t pos;
308 size_t next;
309 int err = 0;
310
311 if (!entry->c.text.write)
312 return -EIO;
313 pos = *offset;
314 if (!valid_pos(pos, count))
315 return -EIO;
316 next = pos + count;
317 /* don't handle too large text inputs */
318 if (next > 16 * 1024)
319 return -EIO;
320 mutex_lock(&entry->access);
321 buf = data->wbuffer;
322 if (!buf) {
323 data->wbuffer = buf = kzalloc(sizeof(*buf), GFP_KERNEL);
324 if (!buf) {
325 err = -ENOMEM;
326 goto error;
327 }
328 }
329 if (next > buf->len) {
330 char *nbuf = kvzalloc(PAGE_ALIGN(next), GFP_KERNEL);
331 if (!nbuf) {
332 err = -ENOMEM;
333 goto error;
334 }
335 kvfree(buf->buffer);
336 buf->buffer = nbuf;
337 buf->len = PAGE_ALIGN(next);
338 }
339 if (copy_from_user(buf->buffer + pos, buffer, count)) {
340 err = -EFAULT;
341 goto error;
342 }
343 buf->size = next;
344 error:
345 mutex_unlock(&entry->access);
346 if (err < 0)
347 return err;
348 *offset = next;
349 return count;
350}
351
352static int snd_info_seq_show(struct seq_file *seq, void *p)
353{
354 struct snd_info_private_data *data = seq->private;
355 struct snd_info_entry *entry = data->entry;
356
357 if (!entry->c.text.read) {
358 return -EIO;
359 } else {
360 data->rbuffer->buffer = (char *)seq; /* XXX hack! */
361 entry->c.text.read(entry, data->rbuffer);
362 }
363 return 0;
364}
365
366static int snd_info_text_entry_open(struct inode *inode, struct file *file)
367{
368 struct snd_info_entry *entry = pde_data(inode);
369 struct snd_info_private_data *data;
370 int err;
371
372 mutex_lock(&info_mutex);
373 err = alloc_info_private(entry, &data);
374 if (err < 0)
375 goto unlock;
376
377 data->rbuffer = kzalloc(sizeof(*data->rbuffer), GFP_KERNEL);
378 if (!data->rbuffer) {
379 err = -ENOMEM;
380 goto error;
381 }
382 if (entry->size)
383 err = single_open_size(file, snd_info_seq_show, data,
384 entry->size);
385 else
386 err = single_open(file, snd_info_seq_show, data);
387 if (err < 0)
388 goto error;
389 mutex_unlock(&info_mutex);
390 return 0;
391
392 error:
393 kfree(data->rbuffer);
394 kfree(data);
395 module_put(entry->module);
396 unlock:
397 mutex_unlock(&info_mutex);
398 return err;
399}
400
401static int snd_info_text_entry_release(struct inode *inode, struct file *file)
402{
403 struct seq_file *m = file->private_data;
404 struct snd_info_private_data *data = m->private;
405 struct snd_info_entry *entry = data->entry;
406
407 if (data->wbuffer && entry->c.text.write)
408 entry->c.text.write(entry, data->wbuffer);
409
410 single_release(inode, file);
411 kfree(data->rbuffer);
412 if (data->wbuffer) {
413 kvfree(data->wbuffer->buffer);
414 kfree(data->wbuffer);
415 }
416
417 module_put(entry->module);
418 kfree(data);
419 return 0;
420}
421
422static const struct proc_ops snd_info_text_entry_ops =
423{
424 .proc_open = snd_info_text_entry_open,
425 .proc_release = snd_info_text_entry_release,
426 .proc_write = snd_info_text_entry_write,
427 .proc_lseek = seq_lseek,
428 .proc_read = seq_read,
429};
430
431static struct snd_info_entry *create_subdir(struct module *mod,
432 const char *name)
433{
434 struct snd_info_entry *entry;
435
436 entry = snd_info_create_module_entry(mod, name, NULL);
437 if (!entry)
438 return NULL;
439 entry->mode = S_IFDIR | 0555;
440 if (snd_info_register(entry) < 0) {
441 snd_info_free_entry(entry);
442 return NULL;
443 }
444 return entry;
445}
446
447static struct snd_info_entry *
448snd_info_create_entry(const char *name, struct snd_info_entry *parent,
449 struct module *module);
450
451int __init snd_info_init(void)
452{
453 snd_proc_root = snd_info_create_entry("asound", NULL, THIS_MODULE);
454 if (!snd_proc_root)
455 return -ENOMEM;
456 snd_proc_root->mode = S_IFDIR | 0555;
457 snd_proc_root->p = proc_mkdir("asound", NULL);
458 if (!snd_proc_root->p)
459 goto error;
460#ifdef CONFIG_SND_OSSEMUL
461 snd_oss_root = create_subdir(THIS_MODULE, "oss");
462 if (!snd_oss_root)
463 goto error;
464#endif
465#if IS_ENABLED(CONFIG_SND_SEQUENCER)
466 snd_seq_root = create_subdir(THIS_MODULE, "seq");
467 if (!snd_seq_root)
468 goto error;
469#endif
470 if (snd_info_version_init() < 0 ||
471 snd_minor_info_init() < 0 ||
472 snd_minor_info_oss_init() < 0 ||
473 snd_card_info_init() < 0 ||
474 snd_info_minor_register() < 0)
475 goto error;
476 return 0;
477
478 error:
479 snd_info_free_entry(snd_proc_root);
480 return -ENOMEM;
481}
482
483int __exit snd_info_done(void)
484{
485 snd_info_free_entry(snd_proc_root);
486 return 0;
487}
488
489static void snd_card_id_read(struct snd_info_entry *entry,
490 struct snd_info_buffer *buffer)
491{
492 struct snd_card *card = entry->private_data;
493
494 snd_iprintf(buffer, "%s\n", card->id);
495}
496
497/*
498 * create a card proc file
499 * called from init.c
500 */
501int snd_info_card_create(struct snd_card *card)
502{
503 char str[8];
504 struct snd_info_entry *entry;
505
506 if (snd_BUG_ON(!card))
507 return -ENXIO;
508
509 sprintf(str, "card%i", card->number);
510 entry = create_subdir(card->module, str);
511 if (!entry)
512 return -ENOMEM;
513 card->proc_root = entry;
514
515 return snd_card_ro_proc_new(card, "id", card, snd_card_id_read);
516}
517
518/*
519 * register the card proc file
520 * called from init.c
521 * can be called multiple times for reinitialization
522 */
523int snd_info_card_register(struct snd_card *card)
524{
525 struct proc_dir_entry *p;
526 int err;
527
528 if (snd_BUG_ON(!card))
529 return -ENXIO;
530
531 err = snd_info_register(card->proc_root);
532 if (err < 0)
533 return err;
534
535 if (!strcmp(card->id, card->proc_root->name))
536 return 0;
537
538 if (card->proc_root_link)
539 return 0;
540 p = proc_symlink(card->id, snd_proc_root->p, card->proc_root->name);
541 if (!p)
542 return -ENOMEM;
543 card->proc_root_link = p;
544 return 0;
545}
546
547/*
548 * called on card->id change
549 */
550void snd_info_card_id_change(struct snd_card *card)
551{
552 mutex_lock(&info_mutex);
553 if (card->proc_root_link) {
554 proc_remove(card->proc_root_link);
555 card->proc_root_link = NULL;
556 }
557 if (strcmp(card->id, card->proc_root->name))
558 card->proc_root_link = proc_symlink(card->id,
559 snd_proc_root->p,
560 card->proc_root->name);
561 mutex_unlock(&info_mutex);
562}
563
564/*
565 * de-register the card proc file
566 * called from init.c
567 */
568void snd_info_card_disconnect(struct snd_card *card)
569{
570 if (!card)
571 return;
572 mutex_lock(&info_mutex);
573 proc_remove(card->proc_root_link);
574 card->proc_root_link = NULL;
575 if (card->proc_root)
576 snd_info_disconnect(card->proc_root);
577 mutex_unlock(&info_mutex);
578}
579
580/*
581 * release the card proc file resources
582 * called from init.c
583 */
584int snd_info_card_free(struct snd_card *card)
585{
586 if (!card)
587 return 0;
588 snd_info_free_entry(card->proc_root);
589 card->proc_root = NULL;
590 return 0;
591}
592
593
594/**
595 * snd_info_get_line - read one line from the procfs buffer
596 * @buffer: the procfs buffer
597 * @line: the buffer to store
598 * @len: the max. buffer size
599 *
600 * Reads one line from the buffer and stores the string.
601 *
602 * Return: Zero if successful, or 1 if error or EOF.
603 */
604int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
605{
606 int c;
607
608 if (snd_BUG_ON(!buffer))
609 return 1;
610 if (!buffer->buffer)
611 return 1;
612 if (len <= 0 || buffer->stop || buffer->error)
613 return 1;
614 while (!buffer->stop) {
615 c = buffer->buffer[buffer->curr++];
616 if (buffer->curr >= buffer->size)
617 buffer->stop = 1;
618 if (c == '\n')
619 break;
620 if (len > 1) {
621 len--;
622 *line++ = c;
623 }
624 }
625 *line = '\0';
626 return 0;
627}
628EXPORT_SYMBOL(snd_info_get_line);
629
630/**
631 * snd_info_get_str - parse a string token
632 * @dest: the buffer to store the string token
633 * @src: the original string
634 * @len: the max. length of token - 1
635 *
636 * Parses the original string and copy a token to the given
637 * string buffer.
638 *
639 * Return: The updated pointer of the original string so that
640 * it can be used for the next call.
641 */
642const char *snd_info_get_str(char *dest, const char *src, int len)
643{
644 int c;
645
646 while (*src == ' ' || *src == '\t')
647 src++;
648 if (*src == '"' || *src == '\'') {
649 c = *src++;
650 while (--len > 0 && *src && *src != c) {
651 *dest++ = *src++;
652 }
653 if (*src == c)
654 src++;
655 } else {
656 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
657 *dest++ = *src++;
658 }
659 }
660 *dest = 0;
661 while (*src == ' ' || *src == '\t')
662 src++;
663 return src;
664}
665EXPORT_SYMBOL(snd_info_get_str);
666
667/*
668 * snd_info_create_entry - create an info entry
669 * @name: the proc file name
670 * @parent: the parent directory
671 *
672 * Creates an info entry with the given file name and initializes as
673 * the default state.
674 *
675 * Usually called from other functions such as
676 * snd_info_create_card_entry().
677 *
678 * Return: The pointer of the new instance, or %NULL on failure.
679 */
680static struct snd_info_entry *
681snd_info_create_entry(const char *name, struct snd_info_entry *parent,
682 struct module *module)
683{
684 struct snd_info_entry *entry;
685 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
686 if (entry == NULL)
687 return NULL;
688 entry->name = kstrdup(name, GFP_KERNEL);
689 if (entry->name == NULL) {
690 kfree(entry);
691 return NULL;
692 }
693 entry->mode = S_IFREG | 0444;
694 entry->content = SNDRV_INFO_CONTENT_TEXT;
695 mutex_init(&entry->access);
696 INIT_LIST_HEAD(&entry->children);
697 INIT_LIST_HEAD(&entry->list);
698 entry->parent = parent;
699 entry->module = module;
700 if (parent) {
701 mutex_lock(&parent->access);
702 list_add_tail(&entry->list, &parent->children);
703 mutex_unlock(&parent->access);
704 }
705 return entry;
706}
707
708/**
709 * snd_info_create_module_entry - create an info entry for the given module
710 * @module: the module pointer
711 * @name: the file name
712 * @parent: the parent directory
713 *
714 * Creates a new info entry and assigns it to the given module.
715 *
716 * Return: The pointer of the new instance, or %NULL on failure.
717 */
718struct snd_info_entry *snd_info_create_module_entry(struct module * module,
719 const char *name,
720 struct snd_info_entry *parent)
721{
722 if (!parent)
723 parent = snd_proc_root;
724 return snd_info_create_entry(name, parent, module);
725}
726EXPORT_SYMBOL(snd_info_create_module_entry);
727
728/**
729 * snd_info_create_card_entry - create an info entry for the given card
730 * @card: the card instance
731 * @name: the file name
732 * @parent: the parent directory
733 *
734 * Creates a new info entry and assigns it to the given card.
735 *
736 * Return: The pointer of the new instance, or %NULL on failure.
737 */
738struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
739 const char *name,
740 struct snd_info_entry * parent)
741{
742 if (!parent)
743 parent = card->proc_root;
744 return snd_info_create_entry(name, parent, card->module);
745}
746EXPORT_SYMBOL(snd_info_create_card_entry);
747
748static void snd_info_disconnect(struct snd_info_entry *entry)
749{
750 struct snd_info_entry *p;
751
752 if (!entry->p)
753 return;
754 list_for_each_entry(p, &entry->children, list)
755 snd_info_disconnect(p);
756 proc_remove(entry->p);
757 entry->p = NULL;
758}
759
760/**
761 * snd_info_free_entry - release the info entry
762 * @entry: the info entry
763 *
764 * Releases the info entry.
765 */
766void snd_info_free_entry(struct snd_info_entry * entry)
767{
768 struct snd_info_entry *p, *n;
769
770 if (!entry)
771 return;
772 if (entry->p) {
773 mutex_lock(&info_mutex);
774 snd_info_disconnect(entry);
775 mutex_unlock(&info_mutex);
776 }
777
778 /* free all children at first */
779 list_for_each_entry_safe(p, n, &entry->children, list)
780 snd_info_free_entry(p);
781
782 p = entry->parent;
783 if (p) {
784 mutex_lock(&p->access);
785 list_del(&entry->list);
786 mutex_unlock(&p->access);
787 }
788 kfree(entry->name);
789 if (entry->private_free)
790 entry->private_free(entry);
791 kfree(entry);
792}
793EXPORT_SYMBOL(snd_info_free_entry);
794
795static int __snd_info_register(struct snd_info_entry *entry)
796{
797 struct proc_dir_entry *root, *p = NULL;
798
799 if (snd_BUG_ON(!entry))
800 return -ENXIO;
801 root = entry->parent == NULL ? snd_proc_root->p : entry->parent->p;
802 mutex_lock(&info_mutex);
803 if (entry->p || !root)
804 goto unlock;
805 if (S_ISDIR(entry->mode)) {
806 p = proc_mkdir_mode(entry->name, entry->mode, root);
807 if (!p) {
808 mutex_unlock(&info_mutex);
809 return -ENOMEM;
810 }
811 } else {
812 const struct proc_ops *ops;
813 if (entry->content == SNDRV_INFO_CONTENT_DATA)
814 ops = &snd_info_entry_operations;
815 else
816 ops = &snd_info_text_entry_ops;
817 p = proc_create_data(entry->name, entry->mode, root,
818 ops, entry);
819 if (!p) {
820 mutex_unlock(&info_mutex);
821 return -ENOMEM;
822 }
823 proc_set_size(p, entry->size);
824 }
825 entry->p = p;
826 unlock:
827 mutex_unlock(&info_mutex);
828 return 0;
829}
830
831/**
832 * snd_info_register - register the info entry
833 * @entry: the info entry
834 *
835 * Registers the proc info entry.
836 * The all children entries are registered recursively.
837 *
838 * Return: Zero if successful, or a negative error code on failure.
839 */
840int snd_info_register(struct snd_info_entry *entry)
841{
842 struct snd_info_entry *p;
843 int err;
844
845 if (!entry->p) {
846 err = __snd_info_register(entry);
847 if (err < 0)
848 return err;
849 }
850
851 list_for_each_entry(p, &entry->children, list) {
852 err = snd_info_register(p);
853 if (err < 0)
854 return err;
855 }
856
857 return 0;
858}
859EXPORT_SYMBOL(snd_info_register);
860
861/**
862 * snd_card_rw_proc_new - Create a read/write text proc file entry for the card
863 * @card: the card instance
864 * @name: the file name
865 * @private_data: the arbitrary private data
866 * @read: the read callback
867 * @write: the write callback, NULL for read-only
868 *
869 * This proc file entry will be registered via snd_card_register() call, and
870 * it will be removed automatically at the card removal, too.
871 *
872 * Return: zero if successful, or a negative error code
873 */
874int snd_card_rw_proc_new(struct snd_card *card, const char *name,
875 void *private_data,
876 void (*read)(struct snd_info_entry *,
877 struct snd_info_buffer *),
878 void (*write)(struct snd_info_entry *entry,
879 struct snd_info_buffer *buffer))
880{
881 struct snd_info_entry *entry;
882
883 entry = snd_info_create_card_entry(card, name, card->proc_root);
884 if (!entry)
885 return -ENOMEM;
886 snd_info_set_text_ops(entry, private_data, read);
887 if (write) {
888 entry->mode |= 0200;
889 entry->c.text.write = write;
890 }
891 return 0;
892}
893EXPORT_SYMBOL_GPL(snd_card_rw_proc_new);
894
895/*
896
897 */
898
899static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
900{
901 snd_iprintf(buffer,
902 "Advanced Linux Sound Architecture Driver Version k%s.\n",
903 init_utsname()->release);
904}
905
906static int __init snd_info_version_init(void)
907{
908 struct snd_info_entry *entry;
909
910 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
911 if (entry == NULL)
912 return -ENOMEM;
913 entry->c.text.read = snd_info_version_read;
914 return snd_info_register(entry); /* freed in error path */
915}
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 <sound/core.h>
28#include <sound/minors.h>
29#include <sound/info.h>
30#include <sound/version.h>
31#include <linux/proc_fs.h>
32#include <linux/mutex.h>
33#include <stdarg.h>
34
35/*
36 *
37 */
38
39#ifdef CONFIG_PROC_FS
40
41int snd_info_check_reserved_words(const char *str)
42{
43 static char *reserved[] =
44 {
45 "version",
46 "meminfo",
47 "memdebug",
48 "detect",
49 "devices",
50 "oss",
51 "cards",
52 "timers",
53 "synth",
54 "pcm",
55 "seq",
56 NULL
57 };
58 char **xstr = reserved;
59
60 while (*xstr) {
61 if (!strcmp(*xstr, str))
62 return 0;
63 xstr++;
64 }
65 if (!strncmp(str, "card", 4))
66 return 0;
67 return 1;
68}
69
70static DEFINE_MUTEX(info_mutex);
71
72struct snd_info_private_data {
73 struct snd_info_buffer *rbuffer;
74 struct snd_info_buffer *wbuffer;
75 struct snd_info_entry *entry;
76 void *file_private_data;
77};
78
79static int snd_info_version_init(void);
80static int snd_info_version_done(void);
81static void snd_info_disconnect(struct snd_info_entry *entry);
82
83
84/* resize the proc r/w buffer */
85static int resize_info_buffer(struct snd_info_buffer *buffer,
86 unsigned int nsize)
87{
88 char *nbuf;
89
90 nsize = PAGE_ALIGN(nsize);
91 nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL);
92 if (! nbuf)
93 return -ENOMEM;
94
95 buffer->buffer = nbuf;
96 buffer->len = nsize;
97 return 0;
98}
99
100/**
101 * snd_iprintf - printf on the procfs buffer
102 * @buffer: the procfs buffer
103 * @fmt: the printf format
104 *
105 * Outputs the string on the procfs buffer just like printf().
106 *
107 * Returns the size of output string.
108 */
109int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...)
110{
111 va_list args;
112 int len, res;
113 int err = 0;
114
115 might_sleep();
116 if (buffer->stop || buffer->error)
117 return 0;
118 len = buffer->len - buffer->size;
119 va_start(args, fmt);
120 for (;;) {
121 va_list ap;
122 va_copy(ap, args);
123 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
124 va_end(ap);
125 if (res < len)
126 break;
127 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
128 if (err < 0)
129 break;
130 len = buffer->len - buffer->size;
131 }
132 va_end(args);
133
134 if (err < 0)
135 return err;
136 buffer->curr += res;
137 buffer->size += res;
138 return res;
139}
140
141EXPORT_SYMBOL(snd_iprintf);
142
143/*
144
145 */
146
147static struct proc_dir_entry *snd_proc_root;
148struct snd_info_entry *snd_seq_root;
149EXPORT_SYMBOL(snd_seq_root);
150
151#ifdef CONFIG_SND_OSSEMUL
152struct snd_info_entry *snd_oss_root;
153#endif
154
155static void snd_remove_proc_entry(struct proc_dir_entry *parent,
156 struct proc_dir_entry *de)
157{
158 if (de)
159 remove_proc_entry(de->name, parent);
160}
161
162static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
163{
164 struct snd_info_private_data *data;
165 struct snd_info_entry *entry;
166 loff_t ret = -EINVAL, size;
167
168 data = file->private_data;
169 entry = data->entry;
170 mutex_lock(&entry->access);
171 if (entry->content == SNDRV_INFO_CONTENT_DATA &&
172 entry->c.ops->llseek) {
173 offset = entry->c.ops->llseek(entry,
174 data->file_private_data,
175 file, offset, orig);
176 goto out;
177 }
178 if (entry->content == SNDRV_INFO_CONTENT_DATA)
179 size = entry->size;
180 else
181 size = 0;
182 switch (orig) {
183 case SEEK_SET:
184 break;
185 case SEEK_CUR:
186 offset += file->f_pos;
187 break;
188 case SEEK_END:
189 if (!size)
190 goto out;
191 offset += size;
192 break;
193 default:
194 goto out;
195 }
196 if (offset < 0)
197 goto out;
198 if (size && offset > size)
199 offset = size;
200 file->f_pos = offset;
201 ret = offset;
202 out:
203 mutex_unlock(&entry->access);
204 return ret;
205}
206
207static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
208 size_t count, loff_t * offset)
209{
210 struct snd_info_private_data *data;
211 struct snd_info_entry *entry;
212 struct snd_info_buffer *buf;
213 size_t size = 0;
214 loff_t pos;
215
216 data = file->private_data;
217 if (snd_BUG_ON(!data))
218 return -ENXIO;
219 pos = *offset;
220 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
221 return -EIO;
222 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
223 return -EIO;
224 entry = data->entry;
225 switch (entry->content) {
226 case SNDRV_INFO_CONTENT_TEXT:
227 buf = data->rbuffer;
228 if (buf == NULL)
229 return -EIO;
230 if (pos >= buf->size)
231 return 0;
232 size = buf->size - pos;
233 size = min(count, size);
234 if (copy_to_user(buffer, buf->buffer + pos, size))
235 return -EFAULT;
236 break;
237 case SNDRV_INFO_CONTENT_DATA:
238 if (pos >= entry->size)
239 return 0;
240 if (entry->c.ops->read) {
241 size = entry->size - pos;
242 size = min(count, size);
243 size = entry->c.ops->read(entry,
244 data->file_private_data,
245 file, buffer, size, pos);
246 }
247 break;
248 }
249 if ((ssize_t) size > 0)
250 *offset = pos + size;
251 return size;
252}
253
254static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
255 size_t count, loff_t * offset)
256{
257 struct snd_info_private_data *data;
258 struct snd_info_entry *entry;
259 struct snd_info_buffer *buf;
260 ssize_t size = 0;
261 loff_t pos;
262
263 data = file->private_data;
264 if (snd_BUG_ON(!data))
265 return -ENXIO;
266 entry = data->entry;
267 pos = *offset;
268 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
269 return -EIO;
270 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
271 return -EIO;
272 switch (entry->content) {
273 case SNDRV_INFO_CONTENT_TEXT:
274 buf = data->wbuffer;
275 if (buf == NULL)
276 return -EIO;
277 mutex_lock(&entry->access);
278 if (pos + count >= buf->len) {
279 if (resize_info_buffer(buf, pos + count)) {
280 mutex_unlock(&entry->access);
281 return -ENOMEM;
282 }
283 }
284 if (copy_from_user(buf->buffer + pos, buffer, count)) {
285 mutex_unlock(&entry->access);
286 return -EFAULT;
287 }
288 buf->size = pos + count;
289 mutex_unlock(&entry->access);
290 size = count;
291 break;
292 case SNDRV_INFO_CONTENT_DATA:
293 if (entry->c.ops->write && count > 0) {
294 size_t maxsize = entry->size - pos;
295 count = min(count, maxsize);
296 size = entry->c.ops->write(entry,
297 data->file_private_data,
298 file, buffer, count, pos);
299 }
300 break;
301 }
302 if ((ssize_t) size > 0)
303 *offset = pos + size;
304 return size;
305}
306
307static int snd_info_entry_open(struct inode *inode, struct file *file)
308{
309 struct snd_info_entry *entry;
310 struct snd_info_private_data *data;
311 struct snd_info_buffer *buffer;
312 struct proc_dir_entry *p;
313 int mode, err;
314
315 mutex_lock(&info_mutex);
316 p = PDE(inode);
317 entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
318 if (entry == NULL || ! entry->p) {
319 mutex_unlock(&info_mutex);
320 return -ENODEV;
321 }
322 if (!try_module_get(entry->module)) {
323 err = -EFAULT;
324 goto __error1;
325 }
326 mode = file->f_flags & O_ACCMODE;
327 if (mode == O_RDONLY || mode == O_RDWR) {
328 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
329 entry->c.ops->read == NULL)) {
330 err = -ENODEV;
331 goto __error;
332 }
333 }
334 if (mode == O_WRONLY || mode == O_RDWR) {
335 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
336 entry->c.ops->write == NULL)) {
337 err = -ENODEV;
338 goto __error;
339 }
340 }
341 data = kzalloc(sizeof(*data), GFP_KERNEL);
342 if (data == NULL) {
343 err = -ENOMEM;
344 goto __error;
345 }
346 data->entry = entry;
347 switch (entry->content) {
348 case SNDRV_INFO_CONTENT_TEXT:
349 if (mode == O_RDONLY || mode == O_RDWR) {
350 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
351 if (buffer == NULL)
352 goto __nomem;
353 data->rbuffer = buffer;
354 buffer->len = PAGE_SIZE;
355 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
356 if (buffer->buffer == NULL)
357 goto __nomem;
358 }
359 if (mode == O_WRONLY || mode == O_RDWR) {
360 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
361 if (buffer == NULL)
362 goto __nomem;
363 data->wbuffer = buffer;
364 buffer->len = PAGE_SIZE;
365 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
366 if (buffer->buffer == NULL)
367 goto __nomem;
368 }
369 break;
370 case SNDRV_INFO_CONTENT_DATA: /* data */
371 if (entry->c.ops->open) {
372 if ((err = entry->c.ops->open(entry, mode,
373 &data->file_private_data)) < 0) {
374 kfree(data);
375 goto __error;
376 }
377 }
378 break;
379 }
380 file->private_data = data;
381 mutex_unlock(&info_mutex);
382 if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
383 (mode == O_RDONLY || mode == O_RDWR)) {
384 if (entry->c.text.read) {
385 mutex_lock(&entry->access);
386 entry->c.text.read(entry, data->rbuffer);
387 mutex_unlock(&entry->access);
388 }
389 }
390 return 0;
391
392 __nomem:
393 if (data->rbuffer) {
394 kfree(data->rbuffer->buffer);
395 kfree(data->rbuffer);
396 }
397 if (data->wbuffer) {
398 kfree(data->wbuffer->buffer);
399 kfree(data->wbuffer);
400 }
401 kfree(data);
402 err = -ENOMEM;
403 __error:
404 module_put(entry->module);
405 __error1:
406 mutex_unlock(&info_mutex);
407 return err;
408}
409
410static int snd_info_entry_release(struct inode *inode, struct file *file)
411{
412 struct snd_info_entry *entry;
413 struct snd_info_private_data *data;
414 int mode;
415
416 mode = file->f_flags & O_ACCMODE;
417 data = file->private_data;
418 entry = data->entry;
419 switch (entry->content) {
420 case SNDRV_INFO_CONTENT_TEXT:
421 if (data->rbuffer) {
422 kfree(data->rbuffer->buffer);
423 kfree(data->rbuffer);
424 }
425 if (data->wbuffer) {
426 if (entry->c.text.write) {
427 entry->c.text.write(entry, data->wbuffer);
428 if (data->wbuffer->error) {
429 snd_printk(KERN_WARNING "data write error to %s (%i)\n",
430 entry->name,
431 data->wbuffer->error);
432 }
433 }
434 kfree(data->wbuffer->buffer);
435 kfree(data->wbuffer);
436 }
437 break;
438 case SNDRV_INFO_CONTENT_DATA:
439 if (entry->c.ops->release)
440 entry->c.ops->release(entry, mode,
441 data->file_private_data);
442 break;
443 }
444 module_put(entry->module);
445 kfree(data);
446 return 0;
447}
448
449static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
450{
451 struct snd_info_private_data *data;
452 struct snd_info_entry *entry;
453 unsigned int mask;
454
455 data = file->private_data;
456 if (data == NULL)
457 return 0;
458 entry = data->entry;
459 mask = 0;
460 switch (entry->content) {
461 case SNDRV_INFO_CONTENT_DATA:
462 if (entry->c.ops->poll)
463 return entry->c.ops->poll(entry,
464 data->file_private_data,
465 file, wait);
466 if (entry->c.ops->read)
467 mask |= POLLIN | POLLRDNORM;
468 if (entry->c.ops->write)
469 mask |= POLLOUT | POLLWRNORM;
470 break;
471 }
472 return mask;
473}
474
475static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
476 unsigned long arg)
477{
478 struct snd_info_private_data *data;
479 struct snd_info_entry *entry;
480
481 data = file->private_data;
482 if (data == NULL)
483 return 0;
484 entry = data->entry;
485 switch (entry->content) {
486 case SNDRV_INFO_CONTENT_DATA:
487 if (entry->c.ops->ioctl)
488 return entry->c.ops->ioctl(entry,
489 data->file_private_data,
490 file, cmd, arg);
491 break;
492 }
493 return -ENOTTY;
494}
495
496static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
497{
498 struct inode *inode = file->f_path.dentry->d_inode;
499 struct snd_info_private_data *data;
500 struct snd_info_entry *entry;
501
502 data = file->private_data;
503 if (data == NULL)
504 return 0;
505 entry = data->entry;
506 switch (entry->content) {
507 case SNDRV_INFO_CONTENT_DATA:
508 if (entry->c.ops->mmap)
509 return entry->c.ops->mmap(entry,
510 data->file_private_data,
511 inode, file, vma);
512 break;
513 }
514 return -ENXIO;
515}
516
517static const struct file_operations snd_info_entry_operations =
518{
519 .owner = THIS_MODULE,
520 .llseek = snd_info_entry_llseek,
521 .read = snd_info_entry_read,
522 .write = snd_info_entry_write,
523 .poll = snd_info_entry_poll,
524 .unlocked_ioctl = snd_info_entry_ioctl,
525 .mmap = snd_info_entry_mmap,
526 .open = snd_info_entry_open,
527 .release = snd_info_entry_release,
528};
529
530int __init snd_info_init(void)
531{
532 struct proc_dir_entry *p;
533
534 p = proc_mkdir("asound", NULL);
535 if (p == NULL)
536 return -ENOMEM;
537 snd_proc_root = p;
538#ifdef CONFIG_SND_OSSEMUL
539 {
540 struct snd_info_entry *entry;
541 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
542 return -ENOMEM;
543 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
544 if (snd_info_register(entry) < 0) {
545 snd_info_free_entry(entry);
546 return -ENOMEM;
547 }
548 snd_oss_root = entry;
549 }
550#endif
551#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
552 {
553 struct snd_info_entry *entry;
554 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
555 return -ENOMEM;
556 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
557 if (snd_info_register(entry) < 0) {
558 snd_info_free_entry(entry);
559 return -ENOMEM;
560 }
561 snd_seq_root = entry;
562 }
563#endif
564 snd_info_version_init();
565 snd_minor_info_init();
566 snd_minor_info_oss_init();
567 snd_card_info_init();
568 return 0;
569}
570
571int __exit snd_info_done(void)
572{
573 snd_card_info_done();
574 snd_minor_info_oss_done();
575 snd_minor_info_done();
576 snd_info_version_done();
577 if (snd_proc_root) {
578#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
579 snd_info_free_entry(snd_seq_root);
580#endif
581#ifdef CONFIG_SND_OSSEMUL
582 snd_info_free_entry(snd_oss_root);
583#endif
584 snd_remove_proc_entry(NULL, snd_proc_root);
585 }
586 return 0;
587}
588
589/*
590
591 */
592
593
594/*
595 * create a card proc file
596 * called from init.c
597 */
598int snd_info_card_create(struct snd_card *card)
599{
600 char str[8];
601 struct snd_info_entry *entry;
602
603 if (snd_BUG_ON(!card))
604 return -ENXIO;
605
606 sprintf(str, "card%i", card->number);
607 if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
608 return -ENOMEM;
609 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
610 if (snd_info_register(entry) < 0) {
611 snd_info_free_entry(entry);
612 return -ENOMEM;
613 }
614 card->proc_root = entry;
615 return 0;
616}
617
618/*
619 * register the card proc file
620 * called from init.c
621 */
622int snd_info_card_register(struct snd_card *card)
623{
624 struct proc_dir_entry *p;
625
626 if (snd_BUG_ON(!card))
627 return -ENXIO;
628
629 if (!strcmp(card->id, card->proc_root->name))
630 return 0;
631
632 p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
633 if (p == NULL)
634 return -ENOMEM;
635 card->proc_root_link = p;
636 return 0;
637}
638
639/*
640 * called on card->id change
641 */
642void snd_info_card_id_change(struct snd_card *card)
643{
644 mutex_lock(&info_mutex);
645 if (card->proc_root_link) {
646 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
647 card->proc_root_link = NULL;
648 }
649 if (strcmp(card->id, card->proc_root->name))
650 card->proc_root_link = proc_symlink(card->id,
651 snd_proc_root,
652 card->proc_root->name);
653 mutex_unlock(&info_mutex);
654}
655
656/*
657 * de-register the card proc file
658 * called from init.c
659 */
660void snd_info_card_disconnect(struct snd_card *card)
661{
662 if (!card)
663 return;
664 mutex_lock(&info_mutex);
665 if (card->proc_root_link) {
666 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
667 card->proc_root_link = NULL;
668 }
669 if (card->proc_root)
670 snd_info_disconnect(card->proc_root);
671 mutex_unlock(&info_mutex);
672}
673
674/*
675 * release the card proc file resources
676 * called from init.c
677 */
678int snd_info_card_free(struct snd_card *card)
679{
680 if (!card)
681 return 0;
682 snd_info_free_entry(card->proc_root);
683 card->proc_root = NULL;
684 return 0;
685}
686
687
688/**
689 * snd_info_get_line - read one line from the procfs buffer
690 * @buffer: the procfs buffer
691 * @line: the buffer to store
692 * @len: the max. buffer size - 1
693 *
694 * Reads one line from the buffer and stores the string.
695 *
696 * Returns zero if successful, or 1 if error or EOF.
697 */
698int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
699{
700 int c = -1;
701
702 if (len <= 0 || buffer->stop || buffer->error)
703 return 1;
704 while (--len > 0) {
705 c = buffer->buffer[buffer->curr++];
706 if (c == '\n') {
707 if (buffer->curr >= buffer->size)
708 buffer->stop = 1;
709 break;
710 }
711 *line++ = c;
712 if (buffer->curr >= buffer->size) {
713 buffer->stop = 1;
714 break;
715 }
716 }
717 while (c != '\n' && !buffer->stop) {
718 c = buffer->buffer[buffer->curr++];
719 if (buffer->curr >= buffer->size)
720 buffer->stop = 1;
721 }
722 *line = '\0';
723 return 0;
724}
725
726EXPORT_SYMBOL(snd_info_get_line);
727
728/**
729 * snd_info_get_str - parse a string token
730 * @dest: the buffer to store the string token
731 * @src: the original string
732 * @len: the max. length of token - 1
733 *
734 * Parses the original string and copy a token to the given
735 * string buffer.
736 *
737 * Returns the updated pointer of the original string so that
738 * it can be used for the next call.
739 */
740const char *snd_info_get_str(char *dest, const char *src, int len)
741{
742 int c;
743
744 while (*src == ' ' || *src == '\t')
745 src++;
746 if (*src == '"' || *src == '\'') {
747 c = *src++;
748 while (--len > 0 && *src && *src != c) {
749 *dest++ = *src++;
750 }
751 if (*src == c)
752 src++;
753 } else {
754 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
755 *dest++ = *src++;
756 }
757 }
758 *dest = 0;
759 while (*src == ' ' || *src == '\t')
760 src++;
761 return src;
762}
763
764EXPORT_SYMBOL(snd_info_get_str);
765
766/**
767 * snd_info_create_entry - create an info entry
768 * @name: the proc file name
769 *
770 * Creates an info entry with the given file name and initializes as
771 * the default state.
772 *
773 * Usually called from other functions such as
774 * snd_info_create_card_entry().
775 *
776 * Returns the pointer of the new instance, or NULL on failure.
777 */
778static struct snd_info_entry *snd_info_create_entry(const char *name)
779{
780 struct snd_info_entry *entry;
781 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
782 if (entry == NULL)
783 return NULL;
784 entry->name = kstrdup(name, GFP_KERNEL);
785 if (entry->name == NULL) {
786 kfree(entry);
787 return NULL;
788 }
789 entry->mode = S_IFREG | S_IRUGO;
790 entry->content = SNDRV_INFO_CONTENT_TEXT;
791 mutex_init(&entry->access);
792 INIT_LIST_HEAD(&entry->children);
793 INIT_LIST_HEAD(&entry->list);
794 return entry;
795}
796
797/**
798 * snd_info_create_module_entry - create an info entry for the given module
799 * @module: the module pointer
800 * @name: the file name
801 * @parent: the parent directory
802 *
803 * Creates a new info entry and assigns it to the given module.
804 *
805 * Returns the pointer of the new instance, or NULL on failure.
806 */
807struct snd_info_entry *snd_info_create_module_entry(struct module * module,
808 const char *name,
809 struct snd_info_entry *parent)
810{
811 struct snd_info_entry *entry = snd_info_create_entry(name);
812 if (entry) {
813 entry->module = module;
814 entry->parent = parent;
815 }
816 return entry;
817}
818
819EXPORT_SYMBOL(snd_info_create_module_entry);
820
821/**
822 * snd_info_create_card_entry - create an info entry for the given card
823 * @card: the card instance
824 * @name: the file name
825 * @parent: the parent directory
826 *
827 * Creates a new info entry and assigns it to the given card.
828 *
829 * Returns the pointer of the new instance, or NULL on failure.
830 */
831struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
832 const char *name,
833 struct snd_info_entry * parent)
834{
835 struct snd_info_entry *entry = snd_info_create_entry(name);
836 if (entry) {
837 entry->module = card->module;
838 entry->card = card;
839 entry->parent = parent;
840 }
841 return entry;
842}
843
844EXPORT_SYMBOL(snd_info_create_card_entry);
845
846static void snd_info_disconnect(struct snd_info_entry *entry)
847{
848 struct list_head *p, *n;
849 struct proc_dir_entry *root;
850
851 list_for_each_safe(p, n, &entry->children) {
852 snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
853 }
854
855 if (! entry->p)
856 return;
857 list_del_init(&entry->list);
858 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
859 snd_BUG_ON(!root);
860 snd_remove_proc_entry(root, entry->p);
861 entry->p = NULL;
862}
863
864static int snd_info_dev_free_entry(struct snd_device *device)
865{
866 struct snd_info_entry *entry = device->device_data;
867 snd_info_free_entry(entry);
868 return 0;
869}
870
871static int snd_info_dev_register_entry(struct snd_device *device)
872{
873 struct snd_info_entry *entry = device->device_data;
874 return snd_info_register(entry);
875}
876
877/**
878 * snd_card_proc_new - create an info entry for the given card
879 * @card: the card instance
880 * @name: the file name
881 * @entryp: the pointer to store the new info entry
882 *
883 * Creates a new info entry and assigns it to the given card.
884 * Unlike snd_info_create_card_entry(), this function registers the
885 * info entry as an ALSA device component, so that it can be
886 * unregistered/released without explicit call.
887 * Also, you don't have to register this entry via snd_info_register(),
888 * since this will be registered by snd_card_register() automatically.
889 *
890 * The parent is assumed as card->proc_root.
891 *
892 * For releasing this entry, use snd_device_free() instead of
893 * snd_info_free_entry().
894 *
895 * Returns zero if successful, or a negative error code on failure.
896 */
897int snd_card_proc_new(struct snd_card *card, const char *name,
898 struct snd_info_entry **entryp)
899{
900 static struct snd_device_ops ops = {
901 .dev_free = snd_info_dev_free_entry,
902 .dev_register = snd_info_dev_register_entry,
903 /* disconnect is done via snd_info_card_disconnect() */
904 };
905 struct snd_info_entry *entry;
906 int err;
907
908 entry = snd_info_create_card_entry(card, name, card->proc_root);
909 if (! entry)
910 return -ENOMEM;
911 if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
912 snd_info_free_entry(entry);
913 return err;
914 }
915 if (entryp)
916 *entryp = entry;
917 return 0;
918}
919
920EXPORT_SYMBOL(snd_card_proc_new);
921
922/**
923 * snd_info_free_entry - release the info entry
924 * @entry: the info entry
925 *
926 * Releases the info entry. Don't call this after registered.
927 */
928void snd_info_free_entry(struct snd_info_entry * entry)
929{
930 if (entry == NULL)
931 return;
932 if (entry->p) {
933 mutex_lock(&info_mutex);
934 snd_info_disconnect(entry);
935 mutex_unlock(&info_mutex);
936 }
937 kfree(entry->name);
938 if (entry->private_free)
939 entry->private_free(entry);
940 kfree(entry);
941}
942
943EXPORT_SYMBOL(snd_info_free_entry);
944
945/**
946 * snd_info_register - register the info entry
947 * @entry: the info entry
948 *
949 * Registers the proc info entry.
950 *
951 * Returns zero if successful, or a negative error code on failure.
952 */
953int snd_info_register(struct snd_info_entry * entry)
954{
955 struct proc_dir_entry *root, *p = NULL;
956
957 if (snd_BUG_ON(!entry))
958 return -ENXIO;
959 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
960 mutex_lock(&info_mutex);
961 p = create_proc_entry(entry->name, entry->mode, root);
962 if (!p) {
963 mutex_unlock(&info_mutex);
964 return -ENOMEM;
965 }
966 if (!S_ISDIR(entry->mode))
967 p->proc_fops = &snd_info_entry_operations;
968 p->size = entry->size;
969 p->data = entry;
970 entry->p = p;
971 if (entry->parent)
972 list_add_tail(&entry->list, &entry->parent->children);
973 mutex_unlock(&info_mutex);
974 return 0;
975}
976
977EXPORT_SYMBOL(snd_info_register);
978
979/*
980
981 */
982
983static struct snd_info_entry *snd_info_version_entry;
984
985static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
986{
987 snd_iprintf(buffer,
988 "Advanced Linux Sound Architecture Driver Version "
989 CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
990 );
991}
992
993static int __init snd_info_version_init(void)
994{
995 struct snd_info_entry *entry;
996
997 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
998 if (entry == NULL)
999 return -ENOMEM;
1000 entry->c.text.read = snd_info_version_read;
1001 if (snd_info_register(entry) < 0) {
1002 snd_info_free_entry(entry);
1003 return -ENOMEM;
1004 }
1005 snd_info_version_entry = entry;
1006 return 0;
1007}
1008
1009static int __exit snd_info_version_done(void)
1010{
1011 snd_info_free_entry(snd_info_version_entry);
1012 return 0;
1013}
1014
1015#endif /* CONFIG_PROC_FS */