2 * Information interface for ALSA driver
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
22 #include <linux/init.h>
23 #include <linux/time.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include <linux/module.h>
28 #include <sound/core.h>
29 #include <sound/minors.h>
30 #include <sound/info.h>
31 #include <linux/utsname.h>
32 #include <linux/proc_fs.h>
33 #include <linux/mutex.h>
36 int snd_info_check_reserved_words(const char *str
)
38 static char *reserved
[] =
53 char **xstr
= reserved
;
56 if (!strcmp(*xstr
, str
))
60 if (!strncmp(str
, "card", 4))
65 static DEFINE_MUTEX(info_mutex
);
67 struct snd_info_private_data
{
68 struct snd_info_buffer
*rbuffer
;
69 struct snd_info_buffer
*wbuffer
;
70 struct snd_info_entry
*entry
;
71 void *file_private_data
;
74 static int snd_info_version_init(void);
75 static void snd_info_disconnect(struct snd_info_entry
*entry
);
81 static struct snd_info_entry
*snd_proc_root
;
82 struct snd_info_entry
*snd_seq_root
;
83 EXPORT_SYMBOL(snd_seq_root
);
85 #ifdef CONFIG_SND_OSSEMUL
86 struct snd_info_entry
*snd_oss_root
;
89 static int alloc_info_private(struct snd_info_entry
*entry
,
90 struct snd_info_private_data
**ret
)
92 struct snd_info_private_data
*data
;
94 if (!entry
|| !entry
->p
)
96 if (!try_module_get(entry
->module
))
98 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
100 module_put(entry
->module
);
108 static bool valid_pos(loff_t pos
, size_t count
)
110 if (pos
< 0 || (long) pos
!= pos
|| (ssize_t
) count
< 0)
112 if ((unsigned long) pos
+ (unsigned long) count
< (unsigned long) pos
)
118 * file ops for binary proc files
120 static loff_t
snd_info_entry_llseek(struct file
*file
, loff_t offset
, int orig
)
122 struct snd_info_private_data
*data
;
123 struct snd_info_entry
*entry
;
124 loff_t ret
= -EINVAL
, size
;
126 data
= file
->private_data
;
128 mutex_lock(&entry
->access
);
129 if (entry
->c
.ops
->llseek
) {
130 offset
= entry
->c
.ops
->llseek(entry
,
131 data
->file_private_data
,
141 offset
+= file
->f_pos
;
153 if (size
&& offset
> size
)
155 file
->f_pos
= offset
;
158 mutex_unlock(&entry
->access
);
162 static ssize_t
snd_info_entry_read(struct file
*file
, char __user
*buffer
,
163 size_t count
, loff_t
* offset
)
165 struct snd_info_private_data
*data
= file
->private_data
;
166 struct snd_info_entry
*entry
= data
->entry
;
171 if (!valid_pos(pos
, count
))
173 if (pos
>= entry
->size
)
175 size
= entry
->size
- pos
;
176 size
= min(count
, size
);
177 size
= entry
->c
.ops
->read(entry
, data
->file_private_data
,
178 file
, buffer
, size
, pos
);
179 if ((ssize_t
) size
> 0)
180 *offset
= pos
+ size
;
184 static ssize_t
snd_info_entry_write(struct file
*file
, const char __user
*buffer
,
185 size_t count
, loff_t
* offset
)
187 struct snd_info_private_data
*data
= file
->private_data
;
188 struct snd_info_entry
*entry
= data
->entry
;
193 if (!valid_pos(pos
, count
))
196 size_t maxsize
= entry
->size
- pos
;
197 count
= min(count
, maxsize
);
198 size
= entry
->c
.ops
->write(entry
, data
->file_private_data
,
199 file
, buffer
, count
, pos
);
202 *offset
= pos
+ size
;
206 static unsigned int snd_info_entry_poll(struct file
*file
, poll_table
*wait
)
208 struct snd_info_private_data
*data
= file
->private_data
;
209 struct snd_info_entry
*entry
= data
->entry
;
210 unsigned int mask
= 0;
212 if (entry
->c
.ops
->poll
)
213 return entry
->c
.ops
->poll(entry
,
214 data
->file_private_data
,
216 if (entry
->c
.ops
->read
)
217 mask
|= POLLIN
| POLLRDNORM
;
218 if (entry
->c
.ops
->write
)
219 mask
|= POLLOUT
| POLLWRNORM
;
223 static long snd_info_entry_ioctl(struct file
*file
, unsigned int cmd
,
226 struct snd_info_private_data
*data
= file
->private_data
;
227 struct snd_info_entry
*entry
= data
->entry
;
229 if (!entry
->c
.ops
->ioctl
)
231 return entry
->c
.ops
->ioctl(entry
, data
->file_private_data
,
235 static int snd_info_entry_mmap(struct file
*file
, struct vm_area_struct
*vma
)
237 struct inode
*inode
= file_inode(file
);
238 struct snd_info_private_data
*data
;
239 struct snd_info_entry
*entry
;
241 data
= file
->private_data
;
245 if (!entry
->c
.ops
->mmap
)
247 return entry
->c
.ops
->mmap(entry
, data
->file_private_data
,
251 static int snd_info_entry_open(struct inode
*inode
, struct file
*file
)
253 struct snd_info_entry
*entry
= PDE_DATA(inode
);
254 struct snd_info_private_data
*data
;
257 mutex_lock(&info_mutex
);
258 err
= alloc_info_private(entry
, &data
);
262 mode
= file
->f_flags
& O_ACCMODE
;
263 if (((mode
== O_RDONLY
|| mode
== O_RDWR
) && !entry
->c
.ops
->read
) ||
264 ((mode
== O_WRONLY
|| mode
== O_RDWR
) && !entry
->c
.ops
->write
)) {
269 if (entry
->c
.ops
->open
) {
270 err
= entry
->c
.ops
->open(entry
, mode
, &data
->file_private_data
);
275 file
->private_data
= data
;
276 mutex_unlock(&info_mutex
);
281 module_put(entry
->module
);
283 mutex_unlock(&info_mutex
);
287 static int snd_info_entry_release(struct inode
*inode
, struct file
*file
)
289 struct snd_info_private_data
*data
= file
->private_data
;
290 struct snd_info_entry
*entry
= data
->entry
;
292 if (entry
->c
.ops
->release
)
293 entry
->c
.ops
->release(entry
, file
->f_flags
& O_ACCMODE
,
294 data
->file_private_data
);
295 module_put(entry
->module
);
300 static const struct file_operations snd_info_entry_operations
=
302 .owner
= THIS_MODULE
,
303 .llseek
= snd_info_entry_llseek
,
304 .read
= snd_info_entry_read
,
305 .write
= snd_info_entry_write
,
306 .poll
= snd_info_entry_poll
,
307 .unlocked_ioctl
= snd_info_entry_ioctl
,
308 .mmap
= snd_info_entry_mmap
,
309 .open
= snd_info_entry_open
,
310 .release
= snd_info_entry_release
,
314 * file ops for text proc files
316 static ssize_t
snd_info_text_entry_write(struct file
*file
,
317 const char __user
*buffer
,
318 size_t count
, loff_t
*offset
)
320 struct seq_file
*m
= file
->private_data
;
321 struct snd_info_private_data
*data
= m
->private;
322 struct snd_info_entry
*entry
= data
->entry
;
323 struct snd_info_buffer
*buf
;
329 if (!valid_pos(pos
, count
))
332 mutex_lock(&entry
->access
);
335 data
->wbuffer
= buf
= kzalloc(sizeof(*buf
), GFP_KERNEL
);
341 if (next
> buf
->len
) {
342 char *nbuf
= krealloc(buf
->buffer
, PAGE_ALIGN(next
),
343 GFP_KERNEL
| __GFP_ZERO
);
349 buf
->len
= PAGE_ALIGN(next
);
351 if (copy_from_user(buf
->buffer
+ pos
, buffer
, count
)) {
357 mutex_unlock(&entry
->access
);
364 static int snd_info_seq_show(struct seq_file
*seq
, void *p
)
366 struct snd_info_private_data
*data
= seq
->private;
367 struct snd_info_entry
*entry
= data
->entry
;
369 if (entry
->c
.text
.read
) {
370 data
->rbuffer
->buffer
= (char *)seq
; /* XXX hack! */
371 entry
->c
.text
.read(entry
, data
->rbuffer
);
376 static int snd_info_text_entry_open(struct inode
*inode
, struct file
*file
)
378 struct snd_info_entry
*entry
= PDE_DATA(inode
);
379 struct snd_info_private_data
*data
;
382 mutex_lock(&info_mutex
);
383 err
= alloc_info_private(entry
, &data
);
387 data
->rbuffer
= kzalloc(sizeof(*data
->rbuffer
), GFP_KERNEL
);
388 if (!data
->rbuffer
) {
393 err
= single_open_size(file
, snd_info_seq_show
, data
,
396 err
= single_open(file
, snd_info_seq_show
, data
);
399 mutex_unlock(&info_mutex
);
403 kfree(data
->rbuffer
);
405 module_put(entry
->module
);
407 mutex_unlock(&info_mutex
);
411 static int snd_info_text_entry_release(struct inode
*inode
, struct file
*file
)
413 struct seq_file
*m
= file
->private_data
;
414 struct snd_info_private_data
*data
= m
->private;
415 struct snd_info_entry
*entry
= data
->entry
;
417 if (data
->wbuffer
&& entry
->c
.text
.write
)
418 entry
->c
.text
.write(entry
, data
->wbuffer
);
420 single_release(inode
, file
);
421 kfree(data
->rbuffer
);
423 kfree(data
->wbuffer
->buffer
);
424 kfree(data
->wbuffer
);
427 module_put(entry
->module
);
432 static const struct file_operations snd_info_text_entry_ops
=
434 .owner
= THIS_MODULE
,
435 .open
= snd_info_text_entry_open
,
436 .release
= snd_info_text_entry_release
,
437 .write
= snd_info_text_entry_write
,
442 static struct snd_info_entry
*create_subdir(struct module
*mod
,
445 struct snd_info_entry
*entry
;
447 entry
= snd_info_create_module_entry(mod
, name
, NULL
);
450 entry
->mode
= S_IFDIR
| S_IRUGO
| S_IXUGO
;
451 if (snd_info_register(entry
) < 0) {
452 snd_info_free_entry(entry
);
458 static struct snd_info_entry
*snd_info_create_entry(const char *name
);
460 int __init
snd_info_init(void)
462 snd_proc_root
= snd_info_create_entry("asound");
465 snd_proc_root
->mode
= S_IFDIR
| S_IRUGO
| S_IXUGO
;
466 snd_proc_root
->p
= proc_mkdir("asound", NULL
);
467 if (!snd_proc_root
->p
)
469 #ifdef CONFIG_SND_OSSEMUL
470 snd_oss_root
= create_subdir(THIS_MODULE
, "oss");
474 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
475 snd_seq_root
= create_subdir(THIS_MODULE
, "seq");
479 if (snd_info_version_init() < 0 ||
480 snd_minor_info_init() < 0 ||
481 snd_minor_info_oss_init() < 0 ||
482 snd_card_info_init() < 0 ||
483 snd_info_minor_register() < 0)
488 snd_info_free_entry(snd_proc_root
);
492 int __exit
snd_info_done(void)
494 snd_info_free_entry(snd_proc_root
);
499 * create a card proc file
502 int snd_info_card_create(struct snd_card
*card
)
505 struct snd_info_entry
*entry
;
507 if (snd_BUG_ON(!card
))
510 sprintf(str
, "card%i", card
->number
);
511 entry
= create_subdir(card
->module
, str
);
514 card
->proc_root
= entry
;
519 * register the card proc file
522 int snd_info_card_register(struct snd_card
*card
)
524 struct proc_dir_entry
*p
;
526 if (snd_BUG_ON(!card
))
529 if (!strcmp(card
->id
, card
->proc_root
->name
))
532 p
= proc_symlink(card
->id
, snd_proc_root
->p
, card
->proc_root
->name
);
535 card
->proc_root_link
= p
;
540 * called on card->id change
542 void snd_info_card_id_change(struct snd_card
*card
)
544 mutex_lock(&info_mutex
);
545 if (card
->proc_root_link
) {
546 proc_remove(card
->proc_root_link
);
547 card
->proc_root_link
= NULL
;
549 if (strcmp(card
->id
, card
->proc_root
->name
))
550 card
->proc_root_link
= proc_symlink(card
->id
,
552 card
->proc_root
->name
);
553 mutex_unlock(&info_mutex
);
557 * de-register the card proc file
560 void snd_info_card_disconnect(struct snd_card
*card
)
564 mutex_lock(&info_mutex
);
565 proc_remove(card
->proc_root_link
);
566 card
->proc_root_link
= NULL
;
568 snd_info_disconnect(card
->proc_root
);
569 mutex_unlock(&info_mutex
);
573 * release the card proc file resources
576 int snd_info_card_free(struct snd_card
*card
)
580 snd_info_free_entry(card
->proc_root
);
581 card
->proc_root
= NULL
;
587 * snd_info_get_line - read one line from the procfs buffer
588 * @buffer: the procfs buffer
589 * @line: the buffer to store
590 * @len: the max. buffer size
592 * Reads one line from the buffer and stores the string.
594 * Return: Zero if successful, or 1 if error or EOF.
596 int snd_info_get_line(struct snd_info_buffer
*buffer
, char *line
, int len
)
600 if (snd_BUG_ON(!buffer
|| !buffer
->buffer
))
602 if (len
<= 0 || buffer
->stop
|| buffer
->error
)
604 while (!buffer
->stop
) {
605 c
= buffer
->buffer
[buffer
->curr
++];
606 if (buffer
->curr
>= buffer
->size
)
619 EXPORT_SYMBOL(snd_info_get_line
);
622 * snd_info_get_str - parse a string token
623 * @dest: the buffer to store the string token
624 * @src: the original string
625 * @len: the max. length of token - 1
627 * Parses the original string and copy a token to the given
630 * Return: The updated pointer of the original string so that
631 * it can be used for the next call.
633 const char *snd_info_get_str(char *dest
, const char *src
, int len
)
637 while (*src
== ' ' || *src
== '\t')
639 if (*src
== '"' || *src
== '\'') {
641 while (--len
> 0 && *src
&& *src
!= c
) {
647 while (--len
> 0 && *src
&& *src
!= ' ' && *src
!= '\t') {
652 while (*src
== ' ' || *src
== '\t')
657 EXPORT_SYMBOL(snd_info_get_str
);
660 * snd_info_create_entry - create an info entry
661 * @name: the proc file name
663 * Creates an info entry with the given file name and initializes as
666 * Usually called from other functions such as
667 * snd_info_create_card_entry().
669 * Return: The pointer of the new instance, or %NULL on failure.
671 static struct snd_info_entry
*snd_info_create_entry(const char *name
)
673 struct snd_info_entry
*entry
;
674 entry
= kzalloc(sizeof(*entry
), GFP_KERNEL
);
677 entry
->name
= kstrdup(name
, GFP_KERNEL
);
678 if (entry
->name
== NULL
) {
682 entry
->mode
= S_IFREG
| S_IRUGO
;
683 entry
->content
= SNDRV_INFO_CONTENT_TEXT
;
684 mutex_init(&entry
->access
);
685 INIT_LIST_HEAD(&entry
->children
);
686 INIT_LIST_HEAD(&entry
->list
);
691 * snd_info_create_module_entry - create an info entry for the given module
692 * @module: the module pointer
693 * @name: the file name
694 * @parent: the parent directory
696 * Creates a new info entry and assigns it to the given module.
698 * Return: The pointer of the new instance, or %NULL on failure.
700 struct snd_info_entry
*snd_info_create_module_entry(struct module
* module
,
702 struct snd_info_entry
*parent
)
704 struct snd_info_entry
*entry
= snd_info_create_entry(name
);
706 entry
->module
= module
;
707 entry
->parent
= parent
;
712 EXPORT_SYMBOL(snd_info_create_module_entry
);
715 * snd_info_create_card_entry - create an info entry for the given card
716 * @card: the card instance
717 * @name: the file name
718 * @parent: the parent directory
720 * Creates a new info entry and assigns it to the given card.
722 * Return: The pointer of the new instance, or %NULL on failure.
724 struct snd_info_entry
*snd_info_create_card_entry(struct snd_card
*card
,
726 struct snd_info_entry
* parent
)
728 struct snd_info_entry
*entry
= snd_info_create_entry(name
);
730 entry
->module
= card
->module
;
732 entry
->parent
= parent
;
737 EXPORT_SYMBOL(snd_info_create_card_entry
);
739 static void snd_info_disconnect(struct snd_info_entry
*entry
)
741 struct snd_info_entry
*p
, *n
;
745 list_for_each_entry_safe(p
, n
, &entry
->children
, list
)
746 snd_info_disconnect(p
);
747 list_del_init(&entry
->list
);
748 proc_remove(entry
->p
);
753 * snd_info_free_entry - release the info entry
754 * @entry: the info entry
756 * Releases the info entry.
758 void snd_info_free_entry(struct snd_info_entry
* entry
)
760 struct snd_info_entry
*p
, *n
;
765 mutex_lock(&info_mutex
);
766 snd_info_disconnect(entry
);
767 mutex_unlock(&info_mutex
);
770 /* free all children at first */
771 list_for_each_entry_safe(p
, n
, &entry
->children
, list
)
772 snd_info_free_entry(p
);
775 if (entry
->private_free
)
776 entry
->private_free(entry
);
780 EXPORT_SYMBOL(snd_info_free_entry
);
783 * snd_info_register - register the info entry
784 * @entry: the info entry
786 * Registers the proc info entry.
788 * Return: Zero if successful, or a negative error code on failure.
790 int snd_info_register(struct snd_info_entry
* entry
)
792 struct proc_dir_entry
*root
, *p
= NULL
;
794 if (snd_BUG_ON(!entry
))
796 root
= entry
->parent
== NULL
? snd_proc_root
->p
: entry
->parent
->p
;
797 mutex_lock(&info_mutex
);
798 if (S_ISDIR(entry
->mode
)) {
799 p
= proc_mkdir_mode(entry
->name
, entry
->mode
, root
);
801 mutex_unlock(&info_mutex
);
805 const struct file_operations
*ops
;
806 if (entry
->content
== SNDRV_INFO_CONTENT_DATA
)
807 ops
= &snd_info_entry_operations
;
809 ops
= &snd_info_text_entry_ops
;
810 p
= proc_create_data(entry
->name
, entry
->mode
, root
,
813 mutex_unlock(&info_mutex
);
816 proc_set_size(p
, entry
->size
);
820 list_add_tail(&entry
->list
, &entry
->parent
->children
);
821 mutex_unlock(&info_mutex
);
825 EXPORT_SYMBOL(snd_info_register
);
831 static void snd_info_version_read(struct snd_info_entry
*entry
, struct snd_info_buffer
*buffer
)
834 "Advanced Linux Sound Architecture Driver Version k%s.\n",
835 init_utsname()->release
);
838 static int __init
snd_info_version_init(void)
840 struct snd_info_entry
*entry
;
842 entry
= snd_info_create_module_entry(THIS_MODULE
, "version", NULL
);
845 entry
->c
.text
.read
= snd_info_version_read
;
846 return snd_info_register(entry
); /* freed in error path */