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