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 */