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>
42 int snd_info_check_reserved_words(const char *str)
44 static char *reserved[] =
59 char **xstr = reserved;
62 if (!strcmp(*xstr, str))
66 if (!strncmp(str, "card", 4))
71 static DEFINE_MUTEX(info_mutex);
73 struct 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;
80 static int snd_info_version_init(void);
81 static int snd_info_version_done(void);
82 static void snd_info_disconnect(struct snd_info_entry *entry);
85 /* resize the proc r/w buffer */
86 static int resize_info_buffer(struct snd_info_buffer *buffer,
91 nsize = PAGE_ALIGN(nsize);
92 nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL | __GFP_ZERO);
96 buffer->buffer = nbuf;
102 * snd_iprintf - printf on the procfs buffer
103 * @buffer: the procfs buffer
104 * @fmt: the printf format
106 * Outputs the string on the procfs buffer just like printf().
108 * Return: The size of output string, or a negative error code.
110 int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...)
117 if (buffer->stop || buffer->error)
119 len = buffer->len - buffer->size;
124 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
128 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
131 len = buffer->len - buffer->size;
142 EXPORT_SYMBOL(snd_iprintf);
148 static struct proc_dir_entry *snd_proc_root;
149 struct snd_info_entry *snd_seq_root;
150 EXPORT_SYMBOL(snd_seq_root);
152 #ifdef CONFIG_SND_OSSEMUL
153 struct snd_info_entry *snd_oss_root;
156 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
158 struct snd_info_private_data *data;
159 struct snd_info_entry *entry;
160 loff_t ret = -EINVAL, size;
162 data = file->private_data;
164 mutex_lock(&entry->access);
165 if (entry->content == SNDRV_INFO_CONTENT_DATA &&
166 entry->c.ops->llseek) {
167 offset = entry->c.ops->llseek(entry,
168 data->file_private_data,
172 if (entry->content == SNDRV_INFO_CONTENT_DATA)
180 offset += file->f_pos;
192 if (size && offset > size)
194 file->f_pos = offset;
197 mutex_unlock(&entry->access);
201 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
202 size_t count, loff_t * offset)
204 struct snd_info_private_data *data;
205 struct snd_info_entry *entry;
206 struct snd_info_buffer *buf;
210 data = file->private_data;
211 if (snd_BUG_ON(!data))
214 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
216 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
219 switch (entry->content) {
220 case SNDRV_INFO_CONTENT_TEXT:
224 if (pos >= buf->size)
226 size = buf->size - pos;
227 size = min(count, size);
228 if (copy_to_user(buffer, buf->buffer + pos, size))
231 case SNDRV_INFO_CONTENT_DATA:
232 if (pos >= entry->size)
234 if (entry->c.ops->read) {
235 size = entry->size - pos;
236 size = min(count, size);
237 size = entry->c.ops->read(entry,
238 data->file_private_data,
239 file, buffer, size, pos);
243 if ((ssize_t) size > 0)
244 *offset = pos + size;
248 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
249 size_t count, loff_t * offset)
251 struct snd_info_private_data *data;
252 struct snd_info_entry *entry;
253 struct snd_info_buffer *buf;
257 data = file->private_data;
258 if (snd_BUG_ON(!data))
262 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
264 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
266 switch (entry->content) {
267 case SNDRV_INFO_CONTENT_TEXT:
271 mutex_lock(&entry->access);
272 if (pos + count >= buf->len) {
273 if (resize_info_buffer(buf, pos + count)) {
274 mutex_unlock(&entry->access);
278 if (copy_from_user(buf->buffer + pos, buffer, count)) {
279 mutex_unlock(&entry->access);
282 buf->size = pos + count;
283 mutex_unlock(&entry->access);
286 case SNDRV_INFO_CONTENT_DATA:
287 if (entry->c.ops->write && count > 0) {
288 size_t maxsize = entry->size - pos;
289 count = min(count, maxsize);
290 size = entry->c.ops->write(entry,
291 data->file_private_data,
292 file, buffer, count, pos);
296 if ((ssize_t) size > 0)
297 *offset = pos + size;
301 static int snd_info_entry_open(struct inode *inode, struct file *file)
303 struct snd_info_entry *entry;
304 struct snd_info_private_data *data;
305 struct snd_info_buffer *buffer;
308 mutex_lock(&info_mutex);
309 entry = PDE_DATA(inode);
310 if (entry == NULL || ! entry->p) {
311 mutex_unlock(&info_mutex);
314 if (!try_module_get(entry->module)) {
318 mode = file->f_flags & O_ACCMODE;
319 if (mode == O_RDONLY || mode == O_RDWR) {
320 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
321 entry->c.ops->read == NULL)) {
326 if (mode == O_WRONLY || mode == O_RDWR) {
327 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
328 entry->c.ops->write == NULL)) {
333 data = kzalloc(sizeof(*data), GFP_KERNEL);
339 switch (entry->content) {
340 case SNDRV_INFO_CONTENT_TEXT:
341 if (mode == O_RDONLY || mode == O_RDWR) {
342 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
345 data->rbuffer = buffer;
346 buffer->len = PAGE_SIZE;
347 buffer->buffer = kzalloc(buffer->len, GFP_KERNEL);
348 if (buffer->buffer == NULL)
351 if (mode == O_WRONLY || mode == O_RDWR) {
352 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
355 data->wbuffer = buffer;
356 buffer->len = PAGE_SIZE;
357 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
358 if (buffer->buffer == NULL)
362 case SNDRV_INFO_CONTENT_DATA: /* data */
363 if (entry->c.ops->open) {
364 if ((err = entry->c.ops->open(entry, mode,
365 &data->file_private_data)) < 0) {
372 file->private_data = data;
373 mutex_unlock(&info_mutex);
374 if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
375 (mode == O_RDONLY || mode == O_RDWR)) {
376 if (entry->c.text.read) {
377 mutex_lock(&entry->access);
378 entry->c.text.read(entry, data->rbuffer);
379 mutex_unlock(&entry->access);
386 kfree(data->rbuffer->buffer);
387 kfree(data->rbuffer);
390 kfree(data->wbuffer->buffer);
391 kfree(data->wbuffer);
396 module_put(entry->module);
398 mutex_unlock(&info_mutex);
402 static int snd_info_entry_release(struct inode *inode, struct file *file)
404 struct snd_info_entry *entry;
405 struct snd_info_private_data *data;
408 mode = file->f_flags & O_ACCMODE;
409 data = file->private_data;
411 switch (entry->content) {
412 case SNDRV_INFO_CONTENT_TEXT:
414 kfree(data->rbuffer->buffer);
415 kfree(data->rbuffer);
418 if (entry->c.text.write) {
419 entry->c.text.write(entry, data->wbuffer);
420 if (data->wbuffer->error) {
421 snd_printk(KERN_WARNING "data write error to %s (%i)\n",
423 data->wbuffer->error);
426 kfree(data->wbuffer->buffer);
427 kfree(data->wbuffer);
430 case SNDRV_INFO_CONTENT_DATA:
431 if (entry->c.ops->release)
432 entry->c.ops->release(entry, mode,
433 data->file_private_data);
436 module_put(entry->module);
441 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
443 struct snd_info_private_data *data;
444 struct snd_info_entry *entry;
447 data = file->private_data;
452 switch (entry->content) {
453 case SNDRV_INFO_CONTENT_DATA:
454 if (entry->c.ops->poll)
455 return entry->c.ops->poll(entry,
456 data->file_private_data,
458 if (entry->c.ops->read)
459 mask |= POLLIN | POLLRDNORM;
460 if (entry->c.ops->write)
461 mask |= POLLOUT | POLLWRNORM;
467 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
470 struct snd_info_private_data *data;
471 struct snd_info_entry *entry;
473 data = file->private_data;
477 switch (entry->content) {
478 case SNDRV_INFO_CONTENT_DATA:
479 if (entry->c.ops->ioctl)
480 return entry->c.ops->ioctl(entry,
481 data->file_private_data,
488 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
490 struct inode *inode = file_inode(file);
491 struct snd_info_private_data *data;
492 struct snd_info_entry *entry;
494 data = file->private_data;
498 switch (entry->content) {
499 case SNDRV_INFO_CONTENT_DATA:
500 if (entry->c.ops->mmap)
501 return entry->c.ops->mmap(entry,
502 data->file_private_data,
509 static const struct file_operations snd_info_entry_operations =
511 .owner = THIS_MODULE,
512 .llseek = snd_info_entry_llseek,
513 .read = snd_info_entry_read,
514 .write = snd_info_entry_write,
515 .poll = snd_info_entry_poll,
516 .unlocked_ioctl = snd_info_entry_ioctl,
517 .mmap = snd_info_entry_mmap,
518 .open = snd_info_entry_open,
519 .release = snd_info_entry_release,
522 int __init snd_info_init(void)
524 struct proc_dir_entry *p;
526 p = proc_mkdir("asound", NULL);
530 #ifdef CONFIG_SND_OSSEMUL
532 struct snd_info_entry *entry;
533 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
535 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
536 if (snd_info_register(entry) < 0) {
537 snd_info_free_entry(entry);
540 snd_oss_root = entry;
543 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
545 struct snd_info_entry *entry;
546 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
548 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
549 if (snd_info_register(entry) < 0) {
550 snd_info_free_entry(entry);
553 snd_seq_root = entry;
556 snd_info_version_init();
557 snd_minor_info_init();
558 snd_minor_info_oss_init();
559 snd_card_info_init();
563 int __exit snd_info_done(void)
565 snd_card_info_done();
566 snd_minor_info_oss_done();
567 snd_minor_info_done();
568 snd_info_version_done();
570 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
571 snd_info_free_entry(snd_seq_root);
573 #ifdef CONFIG_SND_OSSEMUL
574 snd_info_free_entry(snd_oss_root);
576 proc_remove(snd_proc_root);
587 * create a card proc file
590 int snd_info_card_create(struct snd_card *card)
593 struct snd_info_entry *entry;
595 if (snd_BUG_ON(!card))
598 sprintf(str, "card%i", card->number);
599 if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
601 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
602 if (snd_info_register(entry) < 0) {
603 snd_info_free_entry(entry);
606 card->proc_root = entry;
611 * register the card proc file
614 int snd_info_card_register(struct snd_card *card)
616 struct proc_dir_entry *p;
618 if (snd_BUG_ON(!card))
621 if (!strcmp(card->id, card->proc_root->name))
624 p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
627 card->proc_root_link = p;
632 * called on card->id change
634 void snd_info_card_id_change(struct snd_card *card)
636 mutex_lock(&info_mutex);
637 if (card->proc_root_link) {
638 proc_remove(card->proc_root_link);
639 card->proc_root_link = NULL;
641 if (strcmp(card->id, card->proc_root->name))
642 card->proc_root_link = proc_symlink(card->id,
644 card->proc_root->name);
645 mutex_unlock(&info_mutex);
649 * de-register the card proc file
652 void snd_info_card_disconnect(struct snd_card *card)
656 mutex_lock(&info_mutex);
657 proc_remove(card->proc_root_link);
658 card->proc_root_link = NULL;
660 snd_info_disconnect(card->proc_root);
661 mutex_unlock(&info_mutex);
665 * release the card proc file resources
668 int snd_info_card_free(struct snd_card *card)
672 snd_info_free_entry(card->proc_root);
673 card->proc_root = NULL;
679 * snd_info_get_line - read one line from the procfs buffer
680 * @buffer: the procfs buffer
681 * @line: the buffer to store
682 * @len: the max. buffer size - 1
684 * Reads one line from the buffer and stores the string.
686 * Return: Zero if successful, or 1 if error or EOF.
688 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
692 if (snd_BUG_ON(!buffer || !buffer->buffer))
694 if (len <= 0 || buffer->stop || buffer->error)
696 while (!buffer->stop) {
697 c = buffer->buffer[buffer->curr++];
698 if (buffer->curr >= buffer->size)
711 EXPORT_SYMBOL(snd_info_get_line);
714 * snd_info_get_str - parse a string token
715 * @dest: the buffer to store the string token
716 * @src: the original string
717 * @len: the max. length of token - 1
719 * Parses the original string and copy a token to the given
722 * Return: The updated pointer of the original string so that
723 * it can be used for the next call.
725 const char *snd_info_get_str(char *dest, const char *src, int len)
729 while (*src == ' ' || *src == '\t')
731 if (*src == '"' || *src == '\'') {
733 while (--len > 0 && *src && *src != c) {
739 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
744 while (*src == ' ' || *src == '\t')
749 EXPORT_SYMBOL(snd_info_get_str);
752 * snd_info_create_entry - create an info entry
753 * @name: the proc file name
755 * Creates an info entry with the given file name and initializes as
758 * Usually called from other functions such as
759 * snd_info_create_card_entry().
761 * Return: The pointer of the new instance, or %NULL on failure.
763 static struct snd_info_entry *snd_info_create_entry(const char *name)
765 struct snd_info_entry *entry;
766 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
769 entry->name = kstrdup(name, GFP_KERNEL);
770 if (entry->name == NULL) {
774 entry->mode = S_IFREG | S_IRUGO;
775 entry->content = SNDRV_INFO_CONTENT_TEXT;
776 mutex_init(&entry->access);
777 INIT_LIST_HEAD(&entry->children);
778 INIT_LIST_HEAD(&entry->list);
783 * snd_info_create_module_entry - create an info entry for the given module
784 * @module: the module pointer
785 * @name: the file name
786 * @parent: the parent directory
788 * Creates a new info entry and assigns it to the given module.
790 * Return: The pointer of the new instance, or %NULL on failure.
792 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
794 struct snd_info_entry *parent)
796 struct snd_info_entry *entry = snd_info_create_entry(name);
798 entry->module = module;
799 entry->parent = parent;
804 EXPORT_SYMBOL(snd_info_create_module_entry);
807 * snd_info_create_card_entry - create an info entry for the given card
808 * @card: the card instance
809 * @name: the file name
810 * @parent: the parent directory
812 * Creates a new info entry and assigns it to the given card.
814 * Return: The pointer of the new instance, or %NULL on failure.
816 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
818 struct snd_info_entry * parent)
820 struct snd_info_entry *entry = snd_info_create_entry(name);
822 entry->module = card->module;
824 entry->parent = parent;
829 EXPORT_SYMBOL(snd_info_create_card_entry);
831 static void snd_info_disconnect(struct snd_info_entry *entry)
833 struct list_head *p, *n;
834 struct proc_dir_entry *root;
836 list_for_each_safe(p, n, &entry->children) {
837 snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
842 list_del_init(&entry->list);
843 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
845 proc_remove(entry->p);
849 static int snd_info_dev_free_entry(struct snd_device *device)
851 struct snd_info_entry *entry = device->device_data;
852 snd_info_free_entry(entry);
856 static int snd_info_dev_register_entry(struct snd_device *device)
858 struct snd_info_entry *entry = device->device_data;
859 return snd_info_register(entry);
863 * snd_card_proc_new - create an info entry for the given card
864 * @card: the card instance
865 * @name: the file name
866 * @entryp: the pointer to store the new info entry
868 * Creates a new info entry and assigns it to the given card.
869 * Unlike snd_info_create_card_entry(), this function registers the
870 * info entry as an ALSA device component, so that it can be
871 * unregistered/released without explicit call.
872 * Also, you don't have to register this entry via snd_info_register(),
873 * since this will be registered by snd_card_register() automatically.
875 * The parent is assumed as card->proc_root.
877 * For releasing this entry, use snd_device_free() instead of
878 * snd_info_free_entry().
880 * Return: Zero if successful, or a negative error code on failure.
882 int snd_card_proc_new(struct snd_card *card, const char *name,
883 struct snd_info_entry **entryp)
885 static struct snd_device_ops ops = {
886 .dev_free = snd_info_dev_free_entry,
887 .dev_register = snd_info_dev_register_entry,
888 /* disconnect is done via snd_info_card_disconnect() */
890 struct snd_info_entry *entry;
893 entry = snd_info_create_card_entry(card, name, card->proc_root);
896 if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
897 snd_info_free_entry(entry);
905 EXPORT_SYMBOL(snd_card_proc_new);
908 * snd_info_free_entry - release the info entry
909 * @entry: the info entry
911 * Releases the info entry. Don't call this after registered.
913 void snd_info_free_entry(struct snd_info_entry * entry)
918 mutex_lock(&info_mutex);
919 snd_info_disconnect(entry);
920 mutex_unlock(&info_mutex);
923 if (entry->private_free)
924 entry->private_free(entry);
928 EXPORT_SYMBOL(snd_info_free_entry);
931 * snd_info_register - register the info entry
932 * @entry: the info entry
934 * Registers the proc info entry.
936 * Return: Zero if successful, or a negative error code on failure.
938 int snd_info_register(struct snd_info_entry * entry)
940 struct proc_dir_entry *root, *p = NULL;
942 if (snd_BUG_ON(!entry))
944 root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
945 mutex_lock(&info_mutex);
946 if (S_ISDIR(entry->mode)) {
947 p = proc_mkdir_mode(entry->name, entry->mode, root);
949 mutex_unlock(&info_mutex);
953 p = proc_create_data(entry->name, entry->mode, root,
954 &snd_info_entry_operations, entry);
956 mutex_unlock(&info_mutex);
959 proc_set_size(p, entry->size);
963 list_add_tail(&entry->list, &entry->parent->children);
964 mutex_unlock(&info_mutex);
968 EXPORT_SYMBOL(snd_info_register);
974 static struct snd_info_entry *snd_info_version_entry;
976 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
979 "Advanced Linux Sound Architecture Driver Version k%s.\n",
980 init_utsname()->release);
983 static int __init snd_info_version_init(void)
985 struct snd_info_entry *entry;
987 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
990 entry->c.text.read = snd_info_version_read;
991 if (snd_info_register(entry) < 0) {
992 snd_info_free_entry(entry);
995 snd_info_version_entry = entry;
999 static int __exit snd_info_version_done(void)
1001 snd_info_free_entry(snd_info_version_entry);
1005 #endif /* CONFIG_PROC_FS */