microblaze: uaccess: fix put_user and get_user macros
[linux-2.6.git] / sound / core / info.c
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/smp_lock.h>
26 #include <linux/string.h>
27 #include <sound/core.h>
28 #include <sound/minors.h>
29 #include <sound/info.h>
30 #include <sound/version.h>
31 #include <linux/proc_fs.h>
32 #include <linux/mutex.h>
33 #include <stdarg.h>
34
35 /*
36  *
37  */
38
39 #ifdef CONFIG_PROC_FS
40
41 int snd_info_check_reserved_words(const char *str)
42 {
43         static char *reserved[] =
44         {
45                 "version",
46                 "meminfo",
47                 "memdebug",
48                 "detect",
49                 "devices",
50                 "oss",
51                 "cards",
52                 "timers",
53                 "synth",
54                 "pcm",
55                 "seq",
56                 NULL
57         };
58         char **xstr = reserved;
59
60         while (*xstr) {
61                 if (!strcmp(*xstr, str))
62                         return 0;
63                 xstr++;
64         }
65         if (!strncmp(str, "card", 4))
66                 return 0;
67         return 1;
68 }
69
70 static DEFINE_MUTEX(info_mutex);
71
72 struct snd_info_private_data {
73         struct snd_info_buffer *rbuffer;
74         struct snd_info_buffer *wbuffer;
75         struct snd_info_entry *entry;
76         void *file_private_data;
77 };
78
79 static int snd_info_version_init(void);
80 static int snd_info_version_done(void);
81 static void snd_info_disconnect(struct snd_info_entry *entry);
82
83
84 /* resize the proc r/w buffer */
85 static int resize_info_buffer(struct snd_info_buffer *buffer,
86                               unsigned int nsize)
87 {
88         char *nbuf;
89
90         nsize = PAGE_ALIGN(nsize);
91         nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL);
92         if (! nbuf)
93                 return -ENOMEM;
94
95         buffer->buffer = nbuf;
96         buffer->len = nsize;
97         return 0;
98 }
99
100 /**
101  * snd_iprintf - printf on the procfs buffer
102  * @buffer: the procfs buffer
103  * @fmt: the printf format
104  *
105  * Outputs the string on the procfs buffer just like printf().
106  *
107  * Returns the size of output string.
108  */
109 int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...)
110 {
111         va_list args;
112         int len, res;
113         int err = 0;
114
115         might_sleep();
116         if (buffer->stop || buffer->error)
117                 return 0;
118         len = buffer->len - buffer->size;
119         va_start(args, fmt);
120         for (;;) {
121                 va_list ap;
122                 va_copy(ap, args);
123                 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
124                 va_end(ap);
125                 if (res < len)
126                         break;
127                 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
128                 if (err < 0)
129                         break;
130                 len = buffer->len - buffer->size;
131         }
132         va_end(args);
133
134         if (err < 0)
135                 return err;
136         buffer->curr += res;
137         buffer->size += res;
138         return res;
139 }
140
141 EXPORT_SYMBOL(snd_iprintf);
142
143 /*
144
145  */
146
147 static struct proc_dir_entry *snd_proc_root;
148 struct snd_info_entry *snd_seq_root;
149 EXPORT_SYMBOL(snd_seq_root);
150
151 #ifdef CONFIG_SND_OSSEMUL
152 struct snd_info_entry *snd_oss_root;
153 #endif
154
155 static void snd_remove_proc_entry(struct proc_dir_entry *parent,
156                                   struct proc_dir_entry *de)
157 {
158         if (de)
159                 remove_proc_entry(de->name, parent);
160 }
161
162 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
163 {
164         struct snd_info_private_data *data;
165         struct snd_info_entry *entry;
166         loff_t ret;
167
168         data = file->private_data;
169         entry = data->entry;
170         lock_kernel();
171         switch (entry->content) {
172         case SNDRV_INFO_CONTENT_TEXT:
173                 switch (orig) {
174                 case SEEK_SET:
175                         file->f_pos = offset;
176                         ret = file->f_pos;
177                         goto out;
178                 case SEEK_CUR:
179                         file->f_pos += offset;
180                         ret = file->f_pos;
181                         goto out;
182                 case SEEK_END:
183                 default:
184                         ret = -EINVAL;
185                         goto out;
186                 }
187                 break;
188         case SNDRV_INFO_CONTENT_DATA:
189                 if (entry->c.ops->llseek) {
190                         ret = entry->c.ops->llseek(entry,
191                                                     data->file_private_data,
192                                                     file, offset, orig);
193                         goto out;
194                 }
195                 break;
196         }
197         ret = -ENXIO;
198 out:
199         unlock_kernel();
200         return ret;
201 }
202
203 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
204                                    size_t count, loff_t * offset)
205 {
206         struct snd_info_private_data *data;
207         struct snd_info_entry *entry;
208         struct snd_info_buffer *buf;
209         size_t size = 0;
210         loff_t pos;
211
212         data = file->private_data;
213         if (snd_BUG_ON(!data))
214                 return -ENXIO;
215         pos = *offset;
216         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
217                 return -EIO;
218         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
219                 return -EIO;
220         entry = data->entry;
221         switch (entry->content) {
222         case SNDRV_INFO_CONTENT_TEXT:
223                 buf = data->rbuffer;
224                 if (buf == NULL)
225                         return -EIO;
226                 if (pos >= buf->size)
227                         return 0;
228                 size = buf->size - pos;
229                 size = min(count, size);
230                 if (copy_to_user(buffer, buf->buffer + pos, size))
231                         return -EFAULT;
232                 break;
233         case SNDRV_INFO_CONTENT_DATA:
234                 if (entry->c.ops->read)
235                         size = entry->c.ops->read(entry,
236                                                   data->file_private_data,
237                                                   file, buffer, count, pos);
238                 break;
239         }
240         if ((ssize_t) size > 0)
241                 *offset = pos + size;
242         return size;
243 }
244
245 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
246                                     size_t count, loff_t * offset)
247 {
248         struct snd_info_private_data *data;
249         struct snd_info_entry *entry;
250         struct snd_info_buffer *buf;
251         ssize_t size = 0;
252         loff_t pos;
253
254         data = file->private_data;
255         if (snd_BUG_ON(!data))
256                 return -ENXIO;
257         entry = data->entry;
258         pos = *offset;
259         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
260                 return -EIO;
261         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
262                 return -EIO;
263         switch (entry->content) {
264         case SNDRV_INFO_CONTENT_TEXT:
265                 buf = data->wbuffer;
266                 if (buf == NULL)
267                         return -EIO;
268                 mutex_lock(&entry->access);
269                 if (pos + count >= buf->len) {
270                         if (resize_info_buffer(buf, pos + count)) {
271                                 mutex_unlock(&entry->access);
272                                 return -ENOMEM;
273                         }
274                 }
275                 if (copy_from_user(buf->buffer + pos, buffer, count)) {
276                         mutex_unlock(&entry->access);
277                         return -EFAULT;
278                 }
279                 buf->size = pos + count;
280                 mutex_unlock(&entry->access);
281                 size = count;
282                 break;
283         case SNDRV_INFO_CONTENT_DATA:
284                 if (entry->c.ops->write)
285                         size = entry->c.ops->write(entry,
286                                                    data->file_private_data,
287                                                    file, buffer, count, pos);
288                 break;
289         }
290         if ((ssize_t) size > 0)
291                 *offset = pos + size;
292         return size;
293 }
294
295 static int snd_info_entry_open(struct inode *inode, struct file *file)
296 {
297         struct snd_info_entry *entry;
298         struct snd_info_private_data *data;
299         struct snd_info_buffer *buffer;
300         struct proc_dir_entry *p;
301         int mode, err;
302
303         mutex_lock(&info_mutex);
304         p = PDE(inode);
305         entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
306         if (entry == NULL || ! entry->p) {
307                 mutex_unlock(&info_mutex);
308                 return -ENODEV;
309         }
310         if (!try_module_get(entry->module)) {
311                 err = -EFAULT;
312                 goto __error1;
313         }
314         mode = file->f_flags & O_ACCMODE;
315         if (mode == O_RDONLY || mode == O_RDWR) {
316                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
317                      entry->c.ops->read == NULL)) {
318                         err = -ENODEV;
319                         goto __error;
320                 }
321         }
322         if (mode == O_WRONLY || mode == O_RDWR) {
323                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
324                      entry->c.ops->write == NULL)) {
325                         err = -ENODEV;
326                         goto __error;
327                 }
328         }
329         data = kzalloc(sizeof(*data), GFP_KERNEL);
330         if (data == NULL) {
331                 err = -ENOMEM;
332                 goto __error;
333         }
334         data->entry = entry;
335         switch (entry->content) {
336         case SNDRV_INFO_CONTENT_TEXT:
337                 if (mode == O_RDONLY || mode == O_RDWR) {
338                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
339                         if (buffer == NULL)
340                                 goto __nomem;
341                         data->rbuffer = buffer;
342                         buffer->len = PAGE_SIZE;
343                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
344                         if (buffer->buffer == NULL)
345                                 goto __nomem;
346                 }
347                 if (mode == O_WRONLY || mode == O_RDWR) {
348                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
349                         if (buffer == NULL)
350                                 goto __nomem;
351                         data->wbuffer = buffer;
352                         buffer->len = PAGE_SIZE;
353                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
354                         if (buffer->buffer == NULL)
355                                 goto __nomem;
356                 }
357                 break;
358         case SNDRV_INFO_CONTENT_DATA:   /* data */
359                 if (entry->c.ops->open) {
360                         if ((err = entry->c.ops->open(entry, mode,
361                                                       &data->file_private_data)) < 0) {
362                                 kfree(data);
363                                 goto __error;
364                         }
365                 }
366                 break;
367         }
368         file->private_data = data;
369         mutex_unlock(&info_mutex);
370         if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
371             (mode == O_RDONLY || mode == O_RDWR)) {
372                 if (entry->c.text.read) {
373                         mutex_lock(&entry->access);
374                         entry->c.text.read(entry, data->rbuffer);
375                         mutex_unlock(&entry->access);
376                 }
377         }
378         return 0;
379
380  __nomem:
381         if (data->rbuffer) {
382                 kfree(data->rbuffer->buffer);
383                 kfree(data->rbuffer);
384         }
385         if (data->wbuffer) {
386                 kfree(data->wbuffer->buffer);
387                 kfree(data->wbuffer);
388         }
389         kfree(data);
390         err = -ENOMEM;
391       __error:
392         module_put(entry->module);
393       __error1:
394         mutex_unlock(&info_mutex);
395         return err;
396 }
397
398 static int snd_info_entry_release(struct inode *inode, struct file *file)
399 {
400         struct snd_info_entry *entry;
401         struct snd_info_private_data *data;
402         int mode;
403
404         mode = file->f_flags & O_ACCMODE;
405         data = file->private_data;
406         entry = data->entry;
407         switch (entry->content) {
408         case SNDRV_INFO_CONTENT_TEXT:
409                 if (data->rbuffer) {
410                         kfree(data->rbuffer->buffer);
411                         kfree(data->rbuffer);
412                 }
413                 if (data->wbuffer) {
414                         if (entry->c.text.write) {
415                                 entry->c.text.write(entry, data->wbuffer);
416                                 if (data->wbuffer->error) {
417                                         snd_printk(KERN_WARNING "data write error to %s (%i)\n",
418                                                 entry->name,
419                                                 data->wbuffer->error);
420                                 }
421                         }
422                         kfree(data->wbuffer->buffer);
423                         kfree(data->wbuffer);
424                 }
425                 break;
426         case SNDRV_INFO_CONTENT_DATA:
427                 if (entry->c.ops->release)
428                         entry->c.ops->release(entry, mode,
429                                               data->file_private_data);
430                 break;
431         }
432         module_put(entry->module);
433         kfree(data);
434         return 0;
435 }
436
437 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
438 {
439         struct snd_info_private_data *data;
440         struct snd_info_entry *entry;
441         unsigned int mask;
442
443         data = file->private_data;
444         if (data == NULL)
445                 return 0;
446         entry = data->entry;
447         mask = 0;
448         switch (entry->content) {
449         case SNDRV_INFO_CONTENT_DATA:
450                 if (entry->c.ops->poll)
451                         return entry->c.ops->poll(entry,
452                                                   data->file_private_data,
453                                                   file, wait);
454                 if (entry->c.ops->read)
455                         mask |= POLLIN | POLLRDNORM;
456                 if (entry->c.ops->write)
457                         mask |= POLLOUT | POLLWRNORM;
458                 break;
459         }
460         return mask;
461 }
462
463 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
464                                 unsigned long arg)
465 {
466         struct snd_info_private_data *data;
467         struct snd_info_entry *entry;
468
469         data = file->private_data;
470         if (data == NULL)
471                 return 0;
472         entry = data->entry;
473         switch (entry->content) {
474         case SNDRV_INFO_CONTENT_DATA:
475                 if (entry->c.ops->ioctl)
476                         return entry->c.ops->ioctl(entry,
477                                                    data->file_private_data,
478                                                    file, cmd, arg);
479                 break;
480         }
481         return -ENOTTY;
482 }
483
484 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
485 {
486         struct inode *inode = file->f_path.dentry->d_inode;
487         struct snd_info_private_data *data;
488         struct snd_info_entry *entry;
489
490         data = file->private_data;
491         if (data == NULL)
492                 return 0;
493         entry = data->entry;
494         switch (entry->content) {
495         case SNDRV_INFO_CONTENT_DATA:
496                 if (entry->c.ops->mmap)
497                         return entry->c.ops->mmap(entry,
498                                                   data->file_private_data,
499                                                   inode, file, vma);
500                 break;
501         }
502         return -ENXIO;
503 }
504
505 static const struct file_operations snd_info_entry_operations =
506 {
507         .owner =                THIS_MODULE,
508         .llseek =               snd_info_entry_llseek,
509         .read =                 snd_info_entry_read,
510         .write =                snd_info_entry_write,
511         .poll =                 snd_info_entry_poll,
512         .unlocked_ioctl =       snd_info_entry_ioctl,
513         .mmap =                 snd_info_entry_mmap,
514         .open =                 snd_info_entry_open,
515         .release =              snd_info_entry_release,
516 };
517
518 int __init snd_info_init(void)
519 {
520         struct proc_dir_entry *p;
521
522         p = create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
523         if (p == NULL)
524                 return -ENOMEM;
525         snd_proc_root = p;
526 #ifdef CONFIG_SND_OSSEMUL
527         {
528                 struct snd_info_entry *entry;
529                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
530                         return -ENOMEM;
531                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
532                 if (snd_info_register(entry) < 0) {
533                         snd_info_free_entry(entry);
534                         return -ENOMEM;
535                 }
536                 snd_oss_root = entry;
537         }
538 #endif
539 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
540         {
541                 struct snd_info_entry *entry;
542                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", 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_seq_root = entry;
550         }
551 #endif
552         snd_info_version_init();
553         snd_minor_info_init();
554         snd_minor_info_oss_init();
555         snd_card_info_init();
556         return 0;
557 }
558
559 int __exit snd_info_done(void)
560 {
561         snd_card_info_done();
562         snd_minor_info_oss_done();
563         snd_minor_info_done();
564         snd_info_version_done();
565         if (snd_proc_root) {
566 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
567                 snd_info_free_entry(snd_seq_root);
568 #endif
569 #ifdef CONFIG_SND_OSSEMUL
570                 snd_info_free_entry(snd_oss_root);
571 #endif
572                 snd_remove_proc_entry(NULL, snd_proc_root);
573         }
574         return 0;
575 }
576
577 /*
578
579  */
580
581
582 /*
583  * create a card proc file
584  * called from init.c
585  */
586 int snd_info_card_create(struct snd_card *card)
587 {
588         char str[8];
589         struct snd_info_entry *entry;
590
591         if (snd_BUG_ON(!card))
592                 return -ENXIO;
593
594         sprintf(str, "card%i", card->number);
595         if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
596                 return -ENOMEM;
597         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
598         if (snd_info_register(entry) < 0) {
599                 snd_info_free_entry(entry);
600                 return -ENOMEM;
601         }
602         card->proc_root = entry;
603         return 0;
604 }
605
606 /*
607  * register the card proc file
608  * called from init.c
609  */
610 int snd_info_card_register(struct snd_card *card)
611 {
612         struct proc_dir_entry *p;
613
614         if (snd_BUG_ON(!card))
615                 return -ENXIO;
616
617         if (!strcmp(card->id, card->proc_root->name))
618                 return 0;
619
620         p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
621         if (p == NULL)
622                 return -ENOMEM;
623         card->proc_root_link = p;
624         return 0;
625 }
626
627 /*
628  * called on card->id change
629  */
630 void snd_info_card_id_change(struct snd_card *card)
631 {
632         mutex_lock(&info_mutex);
633         if (card->proc_root_link) {
634                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
635                 card->proc_root_link = NULL;
636         }
637         if (strcmp(card->id, card->proc_root->name))
638                 card->proc_root_link = proc_symlink(card->id,
639                                                     snd_proc_root,
640                                                     card->proc_root->name);
641         mutex_unlock(&info_mutex);
642 }
643
644 /*
645  * de-register the card proc file
646  * called from init.c
647  */
648 void snd_info_card_disconnect(struct snd_card *card)
649 {
650         if (!card)
651                 return;
652         mutex_lock(&info_mutex);
653         if (card->proc_root_link) {
654                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
655                 card->proc_root_link = NULL;
656         }
657         if (card->proc_root)
658                 snd_info_disconnect(card->proc_root);
659         mutex_unlock(&info_mutex);
660 }
661
662 /*
663  * release the card proc file resources
664  * called from init.c
665  */
666 int snd_info_card_free(struct snd_card *card)
667 {
668         if (!card)
669                 return 0;
670         snd_info_free_entry(card->proc_root);
671         card->proc_root = NULL;
672         return 0;
673 }
674
675
676 /**
677  * snd_info_get_line - read one line from the procfs buffer
678  * @buffer: the procfs buffer
679  * @line: the buffer to store
680  * @len: the max. buffer size - 1
681  *
682  * Reads one line from the buffer and stores the string.
683  *
684  * Returns zero if successful, or 1 if error or EOF.
685  */
686 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
687 {
688         int c = -1;
689
690         if (len <= 0 || buffer->stop || buffer->error)
691                 return 1;
692         while (--len > 0) {
693                 c = buffer->buffer[buffer->curr++];
694                 if (c == '\n') {
695                         if (buffer->curr >= buffer->size)
696                                 buffer->stop = 1;
697                         break;
698                 }
699                 *line++ = c;
700                 if (buffer->curr >= buffer->size) {
701                         buffer->stop = 1;
702                         break;
703                 }
704         }
705         while (c != '\n' && !buffer->stop) {
706                 c = buffer->buffer[buffer->curr++];
707                 if (buffer->curr >= buffer->size)
708                         buffer->stop = 1;
709         }
710         *line = '\0';
711         return 0;
712 }
713
714 EXPORT_SYMBOL(snd_info_get_line);
715
716 /**
717  * snd_info_get_str - parse a string token
718  * @dest: the buffer to store the string token
719  * @src: the original string
720  * @len: the max. length of token - 1
721  *
722  * Parses the original string and copy a token to the given
723  * string buffer.
724  *
725  * Returns the updated pointer of the original string so that
726  * it can be used for the next call.
727  */
728 const char *snd_info_get_str(char *dest, const char *src, int len)
729 {
730         int c;
731
732         while (*src == ' ' || *src == '\t')
733                 src++;
734         if (*src == '"' || *src == '\'') {
735                 c = *src++;
736                 while (--len > 0 && *src && *src != c) {
737                         *dest++ = *src++;
738                 }
739                 if (*src == c)
740                         src++;
741         } else {
742                 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
743                         *dest++ = *src++;
744                 }
745         }
746         *dest = 0;
747         while (*src == ' ' || *src == '\t')
748                 src++;
749         return src;
750 }
751
752 EXPORT_SYMBOL(snd_info_get_str);
753
754 /**
755  * snd_info_create_entry - create an info entry
756  * @name: the proc file name
757  *
758  * Creates an info entry with the given file name and initializes as
759  * the default state.
760  *
761  * Usually called from other functions such as
762  * snd_info_create_card_entry().
763  *
764  * Returns the pointer of the new instance, or NULL on failure.
765  */
766 static struct snd_info_entry *snd_info_create_entry(const char *name)
767 {
768         struct snd_info_entry *entry;
769         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
770         if (entry == NULL)
771                 return NULL;
772         entry->name = kstrdup(name, GFP_KERNEL);
773         if (entry->name == NULL) {
774                 kfree(entry);
775                 return NULL;
776         }
777         entry->mode = S_IFREG | S_IRUGO;
778         entry->content = SNDRV_INFO_CONTENT_TEXT;
779         mutex_init(&entry->access);
780         INIT_LIST_HEAD(&entry->children);
781         INIT_LIST_HEAD(&entry->list);
782         return entry;
783 }
784
785 /**
786  * snd_info_create_module_entry - create an info entry for the given module
787  * @module: the module pointer
788  * @name: the file name
789  * @parent: the parent directory
790  *
791  * Creates a new info entry and assigns it to the given module.
792  *
793  * Returns the pointer of the new instance, or NULL on failure.
794  */
795 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
796                                                const char *name,
797                                                struct snd_info_entry *parent)
798 {
799         struct snd_info_entry *entry = snd_info_create_entry(name);
800         if (entry) {
801                 entry->module = module;
802                 entry->parent = parent;
803         }
804         return entry;
805 }
806
807 EXPORT_SYMBOL(snd_info_create_module_entry);
808
809 /**
810  * snd_info_create_card_entry - create an info entry for the given card
811  * @card: the card instance
812  * @name: the file name
813  * @parent: the parent directory
814  *
815  * Creates a new info entry and assigns it to the given card.
816  *
817  * Returns the pointer of the new instance, or NULL on failure.
818  */
819 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
820                                              const char *name,
821                                              struct snd_info_entry * parent)
822 {
823         struct snd_info_entry *entry = snd_info_create_entry(name);
824         if (entry) {
825                 entry->module = card->module;
826                 entry->card = card;
827                 entry->parent = parent;
828         }
829         return entry;
830 }
831
832 EXPORT_SYMBOL(snd_info_create_card_entry);
833
834 static void snd_info_disconnect(struct snd_info_entry *entry)
835 {
836         struct list_head *p, *n;
837         struct proc_dir_entry *root;
838
839         list_for_each_safe(p, n, &entry->children) {
840                 snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
841         }
842
843         if (! entry->p)
844                 return;
845         list_del_init(&entry->list);
846         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
847         snd_BUG_ON(!root);
848         snd_remove_proc_entry(root, entry->p);
849         entry->p = NULL;
850 }
851
852 static int snd_info_dev_free_entry(struct snd_device *device)
853 {
854         struct snd_info_entry *entry = device->device_data;
855         snd_info_free_entry(entry);
856         return 0;
857 }
858
859 static int snd_info_dev_register_entry(struct snd_device *device)
860 {
861         struct snd_info_entry *entry = device->device_data;
862         return snd_info_register(entry);
863 }
864
865 /**
866  * snd_card_proc_new - create an info entry for the given card
867  * @card: the card instance
868  * @name: the file name
869  * @entryp: the pointer to store the new info entry
870  *
871  * Creates a new info entry and assigns it to the given card.
872  * Unlike snd_info_create_card_entry(), this function registers the
873  * info entry as an ALSA device component, so that it can be
874  * unregistered/released without explicit call.
875  * Also, you don't have to register this entry via snd_info_register(),
876  * since this will be registered by snd_card_register() automatically.
877  *
878  * The parent is assumed as card->proc_root.
879  *
880  * For releasing this entry, use snd_device_free() instead of
881  * snd_info_free_entry(). 
882  *
883  * Returns zero if successful, or a negative error code on failure.
884  */
885 int snd_card_proc_new(struct snd_card *card, const char *name,
886                       struct snd_info_entry **entryp)
887 {
888         static struct snd_device_ops ops = {
889                 .dev_free = snd_info_dev_free_entry,
890                 .dev_register = snd_info_dev_register_entry,
891                 /* disconnect is done via snd_info_card_disconnect() */
892         };
893         struct snd_info_entry *entry;
894         int err;
895
896         entry = snd_info_create_card_entry(card, name, card->proc_root);
897         if (! entry)
898                 return -ENOMEM;
899         if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
900                 snd_info_free_entry(entry);
901                 return err;
902         }
903         if (entryp)
904                 *entryp = entry;
905         return 0;
906 }
907
908 EXPORT_SYMBOL(snd_card_proc_new);
909
910 /**
911  * snd_info_free_entry - release the info entry
912  * @entry: the info entry
913  *
914  * Releases the info entry.  Don't call this after registered.
915  */
916 void snd_info_free_entry(struct snd_info_entry * entry)
917 {
918         if (entry == NULL)
919                 return;
920         if (entry->p) {
921                 mutex_lock(&info_mutex);
922                 snd_info_disconnect(entry);
923                 mutex_unlock(&info_mutex);
924         }
925         kfree(entry->name);
926         if (entry->private_free)
927                 entry->private_free(entry);
928         kfree(entry);
929 }
930
931 EXPORT_SYMBOL(snd_info_free_entry);
932
933 /**
934  * snd_info_register - register the info entry
935  * @entry: the info entry
936  *
937  * Registers the proc info entry.
938  *
939  * Returns zero if successful, or a negative error code on failure.
940  */
941 int snd_info_register(struct snd_info_entry * entry)
942 {
943         struct proc_dir_entry *root, *p = NULL;
944
945         if (snd_BUG_ON(!entry))
946                 return -ENXIO;
947         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
948         mutex_lock(&info_mutex);
949         p = create_proc_entry(entry->name, entry->mode, root);
950         if (!p) {
951                 mutex_unlock(&info_mutex);
952                 return -ENOMEM;
953         }
954         if (!S_ISDIR(entry->mode))
955                 p->proc_fops = &snd_info_entry_operations;
956         p->size = entry->size;
957         p->data = entry;
958         entry->p = p;
959         if (entry->parent)
960                 list_add_tail(&entry->list, &entry->parent->children);
961         mutex_unlock(&info_mutex);
962         return 0;
963 }
964
965 EXPORT_SYMBOL(snd_info_register);
966
967 /*
968
969  */
970
971 static struct snd_info_entry *snd_info_version_entry;
972
973 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
974 {
975         snd_iprintf(buffer,
976                     "Advanced Linux Sound Architecture Driver Version "
977                     CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
978                    );
979 }
980
981 static int __init snd_info_version_init(void)
982 {
983         struct snd_info_entry *entry;
984
985         entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
986         if (entry == NULL)
987                 return -ENOMEM;
988         entry->c.text.read = snd_info_version_read;
989         if (snd_info_register(entry) < 0) {
990                 snd_info_free_entry(entry);
991                 return -ENOMEM;
992         }
993         snd_info_version_entry = entry;
994         return 0;
995 }
996
997 static int __exit snd_info_version_done(void)
998 {
999         snd_info_free_entry(snd_info_version_entry);
1000         return 0;
1001 }
1002
1003 #endif /* CONFIG_PROC_FS */