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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 <linux/module.h>
28#include <sound/core.h>
29#include <sound/minors.h>
30#include <sound/info.h>
31#include <sound/version.h>
32#include <linux/proc_fs.h>
33#include <linux/mutex.h>
34#include <stdarg.h>
35
36/*
37 *
38 */
39
40#ifdef CONFIG_PROC_FS
41
42int snd_info_check_reserved_words(const char *str)
43{
44 static char *reserved[] =
45 {
46 "version",
47 "meminfo",
48 "memdebug",
49 "detect",
50 "devices",
51 "oss",
52 "cards",
53 "timers",
54 "synth",
55 "pcm",
56 "seq",
57 NULL
58 };
59 char **xstr = reserved;
60
61 while (*xstr) {
62 if (!strcmp(*xstr, str))
63 return 0;
64 xstr++;
65 }
66 if (!strncmp(str, "card", 4))
67 return 0;
68 return 1;
69}
70
71static DEFINE_MUTEX(info_mutex);
72
73struct snd_info_private_data {
74 struct snd_info_buffer *rbuffer;
75 struct snd_info_buffer *wbuffer;
76 struct snd_info_entry *entry;
77 void *file_private_data;
78};
79
80static int snd_info_version_init(void);
81static int snd_info_version_done(void);
82static void snd_info_disconnect(struct snd_info_entry *entry);
83
84
85/* resize the proc r/w buffer */
86static int resize_info_buffer(struct snd_info_buffer *buffer,
87 unsigned int nsize)
88{
89 char *nbuf;
90
91 nsize = PAGE_ALIGN(nsize);
92 nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL);
93 if (! nbuf)
94 return -ENOMEM;
95
96 buffer->buffer = nbuf;
97 buffer->len = nsize;
98 return 0;
99}
100
101/**
102 * snd_iprintf - printf on the procfs buffer
103 * @buffer: the procfs buffer
104 * @fmt: the printf format
105 *
106 * Outputs the string on the procfs buffer just like printf().
107 *
108 * Returns the size of output string.
109 */
110int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...)
111{
112 va_list args;
113 int len, res;
114 int err = 0;
115
116 might_sleep();
117 if (buffer->stop || buffer->error)
118 return 0;
119 len = buffer->len - buffer->size;
120 va_start(args, fmt);
121 for (;;) {
122 va_list ap;
123 va_copy(ap, args);
124 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
125 va_end(ap);
126 if (res < len)
127 break;
128 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
129 if (err < 0)
130 break;
131 len = buffer->len - buffer->size;
132 }
133 va_end(args);
134
135 if (err < 0)
136 return err;
137 buffer->curr += res;
138 buffer->size += res;
139 return res;
140}
141
142EXPORT_SYMBOL(snd_iprintf);
143
144/*
145
146 */
147
148static struct proc_dir_entry *snd_proc_root;
149struct snd_info_entry *snd_seq_root;
150EXPORT_SYMBOL(snd_seq_root);
151
152#ifdef CONFIG_SND_OSSEMUL
153struct snd_info_entry *snd_oss_root;
154#endif
155
156static void snd_remove_proc_entry(struct proc_dir_entry *parent,
157 struct proc_dir_entry *de)
158{
159 if (de)
160 remove_proc_entry(de->name, parent);
161}
162
163static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
164{
165 struct snd_info_private_data *data;
166 struct snd_info_entry *entry;
167 loff_t ret = -EINVAL, size;
168
169 data = file->private_data;
170 entry = data->entry;
171 mutex_lock(&entry->access);
172 if (entry->content == SNDRV_INFO_CONTENT_DATA &&
173 entry->c.ops->llseek) {
174 offset = entry->c.ops->llseek(entry,
175 data->file_private_data,
176 file, offset, orig);
177 goto out;
178 }
179 if (entry->content == SNDRV_INFO_CONTENT_DATA)
180 size = entry->size;
181 else
182 size = 0;
183 switch (orig) {
184 case SEEK_SET:
185 break;
186 case SEEK_CUR:
187 offset += file->f_pos;
188 break;
189 case SEEK_END:
190 if (!size)
191 goto out;
192 offset += size;
193 break;
194 default:
195 goto out;
196 }
197 if (offset < 0)
198 goto out;
199 if (size && offset > size)
200 offset = size;
201 file->f_pos = offset;
202 ret = offset;
203 out:
204 mutex_unlock(&entry->access);
205 return ret;
206}
207
208static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
209 size_t count, loff_t * offset)
210{
211 struct snd_info_private_data *data;
212 struct snd_info_entry *entry;
213 struct snd_info_buffer *buf;
214 size_t size = 0;
215 loff_t pos;
216
217 data = file->private_data;
218 if (snd_BUG_ON(!data))
219 return -ENXIO;
220 pos = *offset;
221 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
222 return -EIO;
223 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
224 return -EIO;
225 entry = data->entry;
226 switch (entry->content) {
227 case SNDRV_INFO_CONTENT_TEXT:
228 buf = data->rbuffer;
229 if (buf == NULL)
230 return -EIO;
231 if (pos >= buf->size)
232 return 0;
233 size = buf->size - pos;
234 size = min(count, size);
235 if (copy_to_user(buffer, buf->buffer + pos, size))
236 return -EFAULT;
237 break;
238 case SNDRV_INFO_CONTENT_DATA:
239 if (pos >= entry->size)
240 return 0;
241 if (entry->c.ops->read) {
242 size = entry->size - pos;
243 size = min(count, size);
244 size = entry->c.ops->read(entry,
245 data->file_private_data,
246 file, buffer, size, pos);
247 }
248 break;
249 }
250 if ((ssize_t) size > 0)
251 *offset = pos + size;
252 return size;
253}
254
255static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
256 size_t count, loff_t * offset)
257{
258 struct snd_info_private_data *data;
259 struct snd_info_entry *entry;
260 struct snd_info_buffer *buf;
261 ssize_t size = 0;
262 loff_t pos;
263
264 data = file->private_data;
265 if (snd_BUG_ON(!data))
266 return -ENXIO;
267 entry = data->entry;
268 pos = *offset;
269 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
270 return -EIO;
271 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
272 return -EIO;
273 switch (entry->content) {
274 case SNDRV_INFO_CONTENT_TEXT:
275 buf = data->wbuffer;
276 if (buf == NULL)
277 return -EIO;
278 mutex_lock(&entry->access);
279 if (pos + count >= buf->len) {
280 if (resize_info_buffer(buf, pos + count)) {
281 mutex_unlock(&entry->access);
282 return -ENOMEM;
283 }
284 }
285 if (copy_from_user(buf->buffer + pos, buffer, count)) {
286 mutex_unlock(&entry->access);
287 return -EFAULT;
288 }
289 buf->size = pos + count;
290 mutex_unlock(&entry->access);
291 size = count;
292 break;
293 case SNDRV_INFO_CONTENT_DATA:
294 if (entry->c.ops->write && count > 0) {
295 size_t maxsize = entry->size - pos;
296 count = min(count, maxsize);
297 size = entry->c.ops->write(entry,
298 data->file_private_data,
299 file, buffer, count, pos);
300 }
301 break;
302 }
303 if ((ssize_t) size > 0)
304 *offset = pos + size;
305 return size;
306}
307
308static int snd_info_entry_open(struct inode *inode, struct file *file)
309{
310 struct snd_info_entry *entry;
311 struct snd_info_private_data *data;
312 struct snd_info_buffer *buffer;
313 struct proc_dir_entry *p;
314 int mode, err;
315
316 mutex_lock(&info_mutex);
317 p = PDE(inode);
318 entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
319 if (entry == NULL || ! entry->p) {
320 mutex_unlock(&info_mutex);
321 return -ENODEV;
322 }
323 if (!try_module_get(entry->module)) {
324 err = -EFAULT;
325 goto __error1;
326 }
327 mode = file->f_flags & O_ACCMODE;
328 if (mode == O_RDONLY || mode == O_RDWR) {
329 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
330 entry->c.ops->read == NULL)) {
331 err = -ENODEV;
332 goto __error;
333 }
334 }
335 if (mode == O_WRONLY || mode == O_RDWR) {
336 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
337 entry->c.ops->write == NULL)) {
338 err = -ENODEV;
339 goto __error;
340 }
341 }
342 data = kzalloc(sizeof(*data), GFP_KERNEL);
343 if (data == NULL) {
344 err = -ENOMEM;
345 goto __error;
346 }
347 data->entry = entry;
348 switch (entry->content) {
349 case SNDRV_INFO_CONTENT_TEXT:
350 if (mode == O_RDONLY || mode == O_RDWR) {
351 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
352 if (buffer == NULL)
353 goto __nomem;
354 data->rbuffer = buffer;
355 buffer->len = PAGE_SIZE;
356 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
357 if (buffer->buffer == NULL)
358 goto __nomem;
359 }
360 if (mode == O_WRONLY || mode == O_RDWR) {
361 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
362 if (buffer == NULL)
363 goto __nomem;
364 data->wbuffer = buffer;
365 buffer->len = PAGE_SIZE;
366 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
367 if (buffer->buffer == NULL)
368 goto __nomem;
369 }
370 break;
371 case SNDRV_INFO_CONTENT_DATA: /* data */
372 if (entry->c.ops->open) {
373 if ((err = entry->c.ops->open(entry, mode,
374 &data->file_private_data)) < 0) {
375 kfree(data);
376 goto __error;
377 }
378 }
379 break;
380 }
381 file->private_data = data;
382 mutex_unlock(&info_mutex);
383 if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
384 (mode == O_RDONLY || mode == O_RDWR)) {
385 if (entry->c.text.read) {
386 mutex_lock(&entry->access);
387 entry->c.text.read(entry, data->rbuffer);
388 mutex_unlock(&entry->access);
389 }
390 }
391 return 0;
392
393 __nomem:
394 if (data->rbuffer) {
395 kfree(data->rbuffer->buffer);
396 kfree(data->rbuffer);
397 }
398 if (data->wbuffer) {
399 kfree(data->wbuffer->buffer);
400 kfree(data->wbuffer);
401 }
402 kfree(data);
403 err = -ENOMEM;
404 __error:
405 module_put(entry->module);
406 __error1:
407 mutex_unlock(&info_mutex);
408 return err;
409}
410
411static int snd_info_entry_release(struct inode *inode, struct file *file)
412{
413 struct snd_info_entry *entry;
414 struct snd_info_private_data *data;
415 int mode;
416
417 mode = file->f_flags & O_ACCMODE;
418 data = file->private_data;
419 entry = data->entry;
420 switch (entry->content) {
421 case SNDRV_INFO_CONTENT_TEXT:
422 if (data->rbuffer) {
423 kfree(data->rbuffer->buffer);
424 kfree(data->rbuffer);
425 }
426 if (data->wbuffer) {
427 if (entry->c.text.write) {
428 entry->c.text.write(entry, data->wbuffer);
429 if (data->wbuffer->error) {
430 snd_printk(KERN_WARNING "data write error to %s (%i)\n",
431 entry->name,
432 data->wbuffer->error);
433 }
434 }
435 kfree(data->wbuffer->buffer);
436 kfree(data->wbuffer);
437 }
438 break;
439 case SNDRV_INFO_CONTENT_DATA:
440 if (entry->c.ops->release)
441 entry->c.ops->release(entry, mode,
442 data->file_private_data);
443 break;
444 }
445 module_put(entry->module);
446 kfree(data);
447 return 0;
448}
449
450static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
451{
452 struct snd_info_private_data *data;
453 struct snd_info_entry *entry;
454 unsigned int mask;
455
456 data = file->private_data;
457 if (data == NULL)
458 return 0;
459 entry = data->entry;
460 mask = 0;
461 switch (entry->content) {
462 case SNDRV_INFO_CONTENT_DATA:
463 if (entry->c.ops->poll)
464 return entry->c.ops->poll(entry,
465 data->file_private_data,
466 file, wait);
467 if (entry->c.ops->read)
468 mask |= POLLIN | POLLRDNORM;
469 if (entry->c.ops->write)
470 mask |= POLLOUT | POLLWRNORM;
471 break;
472 }
473 return mask;
474}
475
476static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
477 unsigned long arg)
478{
479 struct snd_info_private_data *data;
480 struct snd_info_entry *entry;
481
482 data = file->private_data;
483 if (data == NULL)
484 return 0;
485 entry = data->entry;
486 switch (entry->content) {
487 case SNDRV_INFO_CONTENT_DATA:
488 if (entry->c.ops->ioctl)
489 return entry->c.ops->ioctl(entry,
490 data->file_private_data,
491 file, cmd, arg);
492 break;
493 }
494 return -ENOTTY;
495}
496
497static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
498{
499 struct inode *inode = file->f_path.dentry->d_inode;
500 struct snd_info_private_data *data;
501 struct snd_info_entry *entry;
502
503 data = file->private_data;
504 if (data == NULL)
505 return 0;
506 entry = data->entry;
507 switch (entry->content) {
508 case SNDRV_INFO_CONTENT_DATA:
509 if (entry->c.ops->mmap)
510 return entry->c.ops->mmap(entry,
511 data->file_private_data,
512 inode, file, vma);
513 break;
514 }
515 return -ENXIO;
516}
517
518static const struct file_operations snd_info_entry_operations =
519{
520 .owner = THIS_MODULE,
521 .llseek = snd_info_entry_llseek,
522 .read = snd_info_entry_read,
523 .write = snd_info_entry_write,
524 .poll = snd_info_entry_poll,
525 .unlocked_ioctl = snd_info_entry_ioctl,
526 .mmap = snd_info_entry_mmap,
527 .open = snd_info_entry_open,
528 .release = snd_info_entry_release,
529};
530
531int __init snd_info_init(void)
532{
533 struct proc_dir_entry *p;
534
535 p = proc_mkdir("asound", NULL);
536 if (p == NULL)
537 return -ENOMEM;
538 snd_proc_root = p;
539#ifdef CONFIG_SND_OSSEMUL
540 {
541 struct snd_info_entry *entry;
542 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
543 return -ENOMEM;
544 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
545 if (snd_info_register(entry) < 0) {
546 snd_info_free_entry(entry);
547 return -ENOMEM;
548 }
549 snd_oss_root = entry;
550 }
551#endif
552#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
553 {
554 struct snd_info_entry *entry;
555 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
556 return -ENOMEM;
557 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
558 if (snd_info_register(entry) < 0) {
559 snd_info_free_entry(entry);
560 return -ENOMEM;
561 }
562 snd_seq_root = entry;
563 }
564#endif
565 snd_info_version_init();
566 snd_minor_info_init();
567 snd_minor_info_oss_init();
568 snd_card_info_init();
569 return 0;
570}
571
572int __exit snd_info_done(void)
573{
574 snd_card_info_done();
575 snd_minor_info_oss_done();
576 snd_minor_info_done();
577 snd_info_version_done();
578 if (snd_proc_root) {
579#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
580 snd_info_free_entry(snd_seq_root);
581#endif
582#ifdef CONFIG_SND_OSSEMUL
583 snd_info_free_entry(snd_oss_root);
584#endif
585 snd_remove_proc_entry(NULL, snd_proc_root);
586 }
587 return 0;
588}
589
590/*
591
592 */
593
594
595/*
596 * create a card proc file
597 * called from init.c
598 */
599int snd_info_card_create(struct snd_card *card)
600{
601 char str[8];
602 struct snd_info_entry *entry;
603
604 if (snd_BUG_ON(!card))
605 return -ENXIO;
606
607 sprintf(str, "card%i", card->number);
608 if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
609 return -ENOMEM;
610 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
611 if (snd_info_register(entry) < 0) {
612 snd_info_free_entry(entry);
613 return -ENOMEM;
614 }
615 card->proc_root = entry;
616 return 0;
617}
618
619/*
620 * register the card proc file
621 * called from init.c
622 */
623int snd_info_card_register(struct snd_card *card)
624{
625 struct proc_dir_entry *p;
626
627 if (snd_BUG_ON(!card))
628 return -ENXIO;
629
630 if (!strcmp(card->id, card->proc_root->name))
631 return 0;
632
633 p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
634 if (p == NULL)
635 return -ENOMEM;
636 card->proc_root_link = p;
637 return 0;
638}
639
640/*
641 * called on card->id change
642 */
643void snd_info_card_id_change(struct snd_card *card)
644{
645 mutex_lock(&info_mutex);
646 if (card->proc_root_link) {
647 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
648 card->proc_root_link = NULL;
649 }
650 if (strcmp(card->id, card->proc_root->name))
651 card->proc_root_link = proc_symlink(card->id,
652 snd_proc_root,
653 card->proc_root->name);
654 mutex_unlock(&info_mutex);
655}
656
657/*
658 * de-register the card proc file
659 * called from init.c
660 */
661void snd_info_card_disconnect(struct snd_card *card)
662{
663 if (!card)
664 return;
665 mutex_lock(&info_mutex);
666 if (card->proc_root_link) {
667 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
668 card->proc_root_link = NULL;
669 }
670 if (card->proc_root)
671 snd_info_disconnect(card->proc_root);
672 mutex_unlock(&info_mutex);
673}
674
675/*
676 * release the card proc file resources
677 * called from init.c
678 */
679int snd_info_card_free(struct snd_card *card)
680{
681 if (!card)
682 return 0;
683 snd_info_free_entry(card->proc_root);
684 card->proc_root = NULL;
685 return 0;
686}
687
688
689/**
690 * snd_info_get_line - read one line from the procfs buffer
691 * @buffer: the procfs buffer
692 * @line: the buffer to store
693 * @len: the max. buffer size - 1
694 *
695 * Reads one line from the buffer and stores the string.
696 *
697 * Returns zero if successful, or 1 if error or EOF.
698 */
699int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
700{
701 int c = -1;
702
703 if (len <= 0 || buffer->stop || buffer->error)
704 return 1;
705 while (--len > 0) {
706 c = buffer->buffer[buffer->curr++];
707 if (c == '\n') {
708 if (buffer->curr >= buffer->size)
709 buffer->stop = 1;
710 break;
711 }
712 *line++ = c;
713 if (buffer->curr >= buffer->size) {
714 buffer->stop = 1;
715 break;
716 }
717 }
718 while (c != '\n' && !buffer->stop) {
719 c = buffer->buffer[buffer->curr++];
720 if (buffer->curr >= buffer->size)
721 buffer->stop = 1;
722 }
723 *line = '\0';
724 return 0;
725}
726
727EXPORT_SYMBOL(snd_info_get_line);
728
729/**
730 * snd_info_get_str - parse a string token
731 * @dest: the buffer to store the string token
732 * @src: the original string
733 * @len: the max. length of token - 1
734 *
735 * Parses the original string and copy a token to the given
736 * string buffer.
737 *
738 * Returns the updated pointer of the original string so that
739 * it can be used for the next call.
740 */
741const char *snd_info_get_str(char *dest, const char *src, int len)
742{
743 int c;
744
745 while (*src == ' ' || *src == '\t')
746 src++;
747 if (*src == '"' || *src == '\'') {
748 c = *src++;
749 while (--len > 0 && *src && *src != c) {
750 *dest++ = *src++;
751 }
752 if (*src == c)
753 src++;
754 } else {
755 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
756 *dest++ = *src++;
757 }
758 }
759 *dest = 0;
760 while (*src == ' ' || *src == '\t')
761 src++;
762 return src;
763}
764
765EXPORT_SYMBOL(snd_info_get_str);
766
767/**
768 * snd_info_create_entry - create an info entry
769 * @name: the proc file name
770 *
771 * Creates an info entry with the given file name and initializes as
772 * the default state.
773 *
774 * Usually called from other functions such as
775 * snd_info_create_card_entry().
776 *
777 * Returns the pointer of the new instance, or NULL on failure.
778 */
779static struct snd_info_entry *snd_info_create_entry(const char *name)
780{
781 struct snd_info_entry *entry;
782 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
783 if (entry == NULL)
784 return NULL;
785 entry->name = kstrdup(name, GFP_KERNEL);
786 if (entry->name == NULL) {
787 kfree(entry);
788 return NULL;
789 }
790 entry->mode = S_IFREG | S_IRUGO;
791 entry->content = SNDRV_INFO_CONTENT_TEXT;
792 mutex_init(&entry->access);
793 INIT_LIST_HEAD(&entry->children);
794 INIT_LIST_HEAD(&entry->list);
795 return entry;
796}
797
798/**
799 * snd_info_create_module_entry - create an info entry for the given module
800 * @module: the module pointer
801 * @name: the file name
802 * @parent: the parent directory
803 *
804 * Creates a new info entry and assigns it to the given module.
805 *
806 * Returns the pointer of the new instance, or NULL on failure.
807 */
808struct snd_info_entry *snd_info_create_module_entry(struct module * module,
809 const char *name,
810 struct snd_info_entry *parent)
811{
812 struct snd_info_entry *entry = snd_info_create_entry(name);
813 if (entry) {
814 entry->module = module;
815 entry->parent = parent;
816 }
817 return entry;
818}
819
820EXPORT_SYMBOL(snd_info_create_module_entry);
821
822/**
823 * snd_info_create_card_entry - create an info entry for the given card
824 * @card: the card instance
825 * @name: the file name
826 * @parent: the parent directory
827 *
828 * Creates a new info entry and assigns it to the given card.
829 *
830 * Returns the pointer of the new instance, or NULL on failure.
831 */
832struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
833 const char *name,
834 struct snd_info_entry * parent)
835{
836 struct snd_info_entry *entry = snd_info_create_entry(name);
837 if (entry) {
838 entry->module = card->module;
839 entry->card = card;
840 entry->parent = parent;
841 }
842 return entry;
843}
844
845EXPORT_SYMBOL(snd_info_create_card_entry);
846
847static void snd_info_disconnect(struct snd_info_entry *entry)
848{
849 struct list_head *p, *n;
850 struct proc_dir_entry *root;
851
852 list_for_each_safe(p, n, &entry->children) {
853 snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
854 }
855
856 if (! entry->p)
857 return;
858 list_del_init(&entry->list);
859 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
860 snd_BUG_ON(!root);
861 snd_remove_proc_entry(root, entry->p);
862 entry->p = NULL;
863}
864
865static int snd_info_dev_free_entry(struct snd_device *device)
866{
867 struct snd_info_entry *entry = device->device_data;
868 snd_info_free_entry(entry);
869 return 0;
870}
871
872static int snd_info_dev_register_entry(struct snd_device *device)
873{
874 struct snd_info_entry *entry = device->device_data;
875 return snd_info_register(entry);
876}
877
878/**
879 * snd_card_proc_new - create an info entry for the given card
880 * @card: the card instance
881 * @name: the file name
882 * @entryp: the pointer to store the new info entry
883 *
884 * Creates a new info entry and assigns it to the given card.
885 * Unlike snd_info_create_card_entry(), this function registers the
886 * info entry as an ALSA device component, so that it can be
887 * unregistered/released without explicit call.
888 * Also, you don't have to register this entry via snd_info_register(),
889 * since this will be registered by snd_card_register() automatically.
890 *
891 * The parent is assumed as card->proc_root.
892 *
893 * For releasing this entry, use snd_device_free() instead of
894 * snd_info_free_entry().
895 *
896 * Returns zero if successful, or a negative error code on failure.
897 */
898int snd_card_proc_new(struct snd_card *card, const char *name,
899 struct snd_info_entry **entryp)
900{
901 static struct snd_device_ops ops = {
902 .dev_free = snd_info_dev_free_entry,
903 .dev_register = snd_info_dev_register_entry,
904 /* disconnect is done via snd_info_card_disconnect() */
905 };
906 struct snd_info_entry *entry;
907 int err;
908
909 entry = snd_info_create_card_entry(card, name, card->proc_root);
910 if (! entry)
911 return -ENOMEM;
912 if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
913 snd_info_free_entry(entry);
914 return err;
915 }
916 if (entryp)
917 *entryp = entry;
918 return 0;
919}
920
921EXPORT_SYMBOL(snd_card_proc_new);
922
923/**
924 * snd_info_free_entry - release the info entry
925 * @entry: the info entry
926 *
927 * Releases the info entry. Don't call this after registered.
928 */
929void snd_info_free_entry(struct snd_info_entry * entry)
930{
931 if (entry == NULL)
932 return;
933 if (entry->p) {
934 mutex_lock(&info_mutex);
935 snd_info_disconnect(entry);
936 mutex_unlock(&info_mutex);
937 }
938 kfree(entry->name);
939 if (entry->private_free)
940 entry->private_free(entry);
941 kfree(entry);
942}
943
944EXPORT_SYMBOL(snd_info_free_entry);
945
946/**
947 * snd_info_register - register the info entry
948 * @entry: the info entry
949 *
950 * Registers the proc info entry.
951 *
952 * Returns zero if successful, or a negative error code on failure.
953 */
954int snd_info_register(struct snd_info_entry * entry)
955{
956 struct proc_dir_entry *root, *p = NULL;
957
958 if (snd_BUG_ON(!entry))
959 return -ENXIO;
960 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
961 mutex_lock(&info_mutex);
962 p = create_proc_entry(entry->name, entry->mode, root);
963 if (!p) {
964 mutex_unlock(&info_mutex);
965 return -ENOMEM;
966 }
967 if (!S_ISDIR(entry->mode))
968 p->proc_fops = &snd_info_entry_operations;
969 p->size = entry->size;
970 p->data = entry;
971 entry->p = p;
972 if (entry->parent)
973 list_add_tail(&entry->list, &entry->parent->children);
974 mutex_unlock(&info_mutex);
975 return 0;
976}
977
978EXPORT_SYMBOL(snd_info_register);
979
980/*
981
982 */
983
984static struct snd_info_entry *snd_info_version_entry;
985
986static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
987{
988 snd_iprintf(buffer,
989 "Advanced Linux Sound Architecture Driver Version "
990 CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
991 );
992}
993
994static int __init snd_info_version_init(void)
995{
996 struct snd_info_entry *entry;
997
998 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
999 if (entry == NULL)
1000 return -ENOMEM;
1001 entry->c.text.read = snd_info_version_read;
1002 if (snd_info_register(entry) < 0) {
1003 snd_info_free_entry(entry);
1004 return -ENOMEM;
1005 }
1006 snd_info_version_entry = entry;
1007 return 0;
1008}
1009
1010static int __exit snd_info_version_done(void)
1011{
1012 snd_info_free_entry(snd_info_version_entry);
1013 return 0;
1014}
1015
1016#endif /* CONFIG_PROC_FS */