proc 2/2: remove struct proc_dir_entry::owner
[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 = kmalloc(nsize, GFP_KERNEL);
92         if (! nbuf)
93                 return -ENOMEM;
94
95         memcpy(nbuf, buffer->buffer, buffer->len);
96         kfree(buffer->buffer);
97         buffer->buffer = nbuf;
98         buffer->len = nsize;
99         return 0;
100 }
101
102 /**
103  * snd_iprintf - printf on the procfs buffer
104  * @buffer: the procfs buffer
105  * @fmt: the printf format
106  *
107  * Outputs the string on the procfs buffer just like printf().
108  *
109  * Returns the size of output string.
110  */
111 int snd_iprintf(struct snd_info_buffer *buffer, char *fmt,...)
112 {
113         va_list args;
114         int len, res;
115         int err = 0;
116
117         might_sleep();
118         if (buffer->stop || buffer->error)
119                 return 0;
120         len = buffer->len - buffer->size;
121         va_start(args, fmt);
122         for (;;) {
123                 va_list ap;
124                 va_copy(ap, args);
125                 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
126                 va_end(ap);
127                 if (res < len)
128                         break;
129                 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
130                 if (err < 0)
131                         break;
132                 len = buffer->len - buffer->size;
133         }
134         va_end(args);
135
136         if (err < 0)
137                 return err;
138         buffer->curr += res;
139         buffer->size += res;
140         return res;
141 }
142
143 EXPORT_SYMBOL(snd_iprintf);
144
145 /*
146
147  */
148
149 static struct proc_dir_entry *snd_proc_root;
150 struct snd_info_entry *snd_seq_root;
151 EXPORT_SYMBOL(snd_seq_root);
152
153 #ifdef CONFIG_SND_OSSEMUL
154 struct snd_info_entry *snd_oss_root;
155 #endif
156
157 static void snd_remove_proc_entry(struct proc_dir_entry *parent,
158                                   struct proc_dir_entry *de)
159 {
160         if (de)
161                 remove_proc_entry(de->name, parent);
162 }
163
164 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
165 {
166         struct snd_info_private_data *data;
167         struct snd_info_entry *entry;
168         loff_t ret;
169
170         data = file->private_data;
171         entry = data->entry;
172         lock_kernel();
173         switch (entry->content) {
174         case SNDRV_INFO_CONTENT_TEXT:
175                 switch (orig) {
176                 case SEEK_SET:
177                         file->f_pos = offset;
178                         ret = file->f_pos;
179                         goto out;
180                 case SEEK_CUR:
181                         file->f_pos += offset;
182                         ret = file->f_pos;
183                         goto out;
184                 case SEEK_END:
185                 default:
186                         ret = -EINVAL;
187                         goto out;
188                 }
189                 break;
190         case SNDRV_INFO_CONTENT_DATA:
191                 if (entry->c.ops->llseek) {
192                         ret = entry->c.ops->llseek(entry,
193                                                     data->file_private_data,
194                                                     file, offset, orig);
195                         goto out;
196                 }
197                 break;
198         }
199         ret = -ENXIO;
200 out:
201         unlock_kernel();
202         return ret;
203 }
204
205 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
206                                    size_t count, loff_t * offset)
207 {
208         struct snd_info_private_data *data;
209         struct snd_info_entry *entry;
210         struct snd_info_buffer *buf;
211         size_t size = 0;
212         loff_t pos;
213
214         data = file->private_data;
215         if (snd_BUG_ON(!data))
216                 return -ENXIO;
217         pos = *offset;
218         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
219                 return -EIO;
220         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
221                 return -EIO;
222         entry = data->entry;
223         switch (entry->content) {
224         case SNDRV_INFO_CONTENT_TEXT:
225                 buf = data->rbuffer;
226                 if (buf == NULL)
227                         return -EIO;
228                 if (pos >= buf->size)
229                         return 0;
230                 size = buf->size - pos;
231                 size = min(count, size);
232                 if (copy_to_user(buffer, buf->buffer + pos, size))
233                         return -EFAULT;
234                 break;
235         case SNDRV_INFO_CONTENT_DATA:
236                 if (entry->c.ops->read)
237                         size = entry->c.ops->read(entry,
238                                                   data->file_private_data,
239                                                   file, buffer, count, pos);
240                 break;
241         }
242         if ((ssize_t) size > 0)
243                 *offset = pos + size;
244         return size;
245 }
246
247 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
248                                     size_t count, loff_t * offset)
249 {
250         struct snd_info_private_data *data;
251         struct snd_info_entry *entry;
252         struct snd_info_buffer *buf;
253         ssize_t size = 0;
254         loff_t pos;
255
256         data = file->private_data;
257         if (snd_BUG_ON(!data))
258                 return -ENXIO;
259         entry = data->entry;
260         pos = *offset;
261         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
262                 return -EIO;
263         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
264                 return -EIO;
265         switch (entry->content) {
266         case SNDRV_INFO_CONTENT_TEXT:
267                 buf = data->wbuffer;
268                 if (buf == NULL)
269                         return -EIO;
270                 mutex_lock(&entry->access);
271                 if (pos + count >= buf->len) {
272                         if (resize_info_buffer(buf, pos + count)) {
273                                 mutex_unlock(&entry->access);
274                                 return -ENOMEM;
275                         }
276                 }
277                 if (copy_from_user(buf->buffer + pos, buffer, count)) {
278                         mutex_unlock(&entry->access);
279                         return -EFAULT;
280                 }
281                 buf->size = pos + count;
282                 mutex_unlock(&entry->access);
283                 size = count;
284                 break;
285         case SNDRV_INFO_CONTENT_DATA:
286                 if (entry->c.ops->write)
287                         size = entry->c.ops->write(entry,
288                                                    data->file_private_data,
289                                                    file, buffer, count, pos);
290                 break;
291         }
292         if ((ssize_t) size > 0)
293                 *offset = pos + size;
294         return size;
295 }
296
297 static int snd_info_entry_open(struct inode *inode, struct file *file)
298 {
299         struct snd_info_entry *entry;
300         struct snd_info_private_data *data;
301         struct snd_info_buffer *buffer;
302         struct proc_dir_entry *p;
303         int mode, err;
304
305         mutex_lock(&info_mutex);
306         p = PDE(inode);
307         entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
308         if (entry == NULL || ! entry->p) {
309                 mutex_unlock(&info_mutex);
310                 return -ENODEV;
311         }
312         if (!try_module_get(entry->module)) {
313                 err = -EFAULT;
314                 goto __error1;
315         }
316         mode = file->f_flags & O_ACCMODE;
317         if (mode == O_RDONLY || mode == O_RDWR) {
318                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
319                      entry->c.ops->read == NULL)) {
320                         err = -ENODEV;
321                         goto __error;
322                 }
323         }
324         if (mode == O_WRONLY || mode == O_RDWR) {
325                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
326                      entry->c.ops->write == NULL)) {
327                         err = -ENODEV;
328                         goto __error;
329                 }
330         }
331         data = kzalloc(sizeof(*data), GFP_KERNEL);
332         if (data == NULL) {
333                 err = -ENOMEM;
334                 goto __error;
335         }
336         data->entry = entry;
337         switch (entry->content) {
338         case SNDRV_INFO_CONTENT_TEXT:
339                 if (mode == O_RDONLY || mode == O_RDWR) {
340                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
341                         if (buffer == NULL)
342                                 goto __nomem;
343                         data->rbuffer = buffer;
344                         buffer->len = PAGE_SIZE;
345                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
346                         if (buffer->buffer == NULL)
347                                 goto __nomem;
348                 }
349                 if (mode == O_WRONLY || mode == O_RDWR) {
350                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
351                         if (buffer == NULL)
352                                 goto __nomem;
353                         data->wbuffer = buffer;
354                         buffer->len = PAGE_SIZE;
355                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
356                         if (buffer->buffer == NULL)
357                                 goto __nomem;
358                 }
359                 break;
360         case SNDRV_INFO_CONTENT_DATA:   /* data */
361                 if (entry->c.ops->open) {
362                         if ((err = entry->c.ops->open(entry, mode,
363                                                       &data->file_private_data)) < 0) {
364                                 kfree(data);
365                                 goto __error;
366                         }
367                 }
368                 break;
369         }
370         file->private_data = data;
371         mutex_unlock(&info_mutex);
372         if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
373             (mode == O_RDONLY || mode == O_RDWR)) {
374                 if (entry->c.text.read) {
375                         mutex_lock(&entry->access);
376                         entry->c.text.read(entry, data->rbuffer);
377                         mutex_unlock(&entry->access);
378                 }
379         }
380         return 0;
381
382  __nomem:
383         if (data->rbuffer) {
384                 kfree(data->rbuffer->buffer);
385                 kfree(data->rbuffer);
386         }
387         if (data->wbuffer) {
388                 kfree(data->wbuffer->buffer);
389                 kfree(data->wbuffer);
390         }
391         kfree(data);
392         err = -ENOMEM;
393       __error:
394         module_put(entry->module);
395       __error1:
396         mutex_unlock(&info_mutex);
397         return err;
398 }
399
400 static int snd_info_entry_release(struct inode *inode, struct file *file)
401 {
402         struct snd_info_entry *entry;
403         struct snd_info_private_data *data;
404         int mode;
405
406         mode = file->f_flags & O_ACCMODE;
407         data = file->private_data;
408         entry = data->entry;
409         switch (entry->content) {
410         case SNDRV_INFO_CONTENT_TEXT:
411                 if (data->rbuffer) {
412                         kfree(data->rbuffer->buffer);
413                         kfree(data->rbuffer);
414                 }
415                 if (data->wbuffer) {
416                         if (entry->c.text.write) {
417                                 entry->c.text.write(entry, data->wbuffer);
418                                 if (data->wbuffer->error) {
419                                         snd_printk(KERN_WARNING "data write error to %s (%i)\n",
420                                                 entry->name,
421                                                 data->wbuffer->error);
422                                 }
423                         }
424                         kfree(data->wbuffer->buffer);
425                         kfree(data->wbuffer);
426                 }
427                 break;
428         case SNDRV_INFO_CONTENT_DATA:
429                 if (entry->c.ops->release)
430                         entry->c.ops->release(entry, mode,
431                                               data->file_private_data);
432                 break;
433         }
434         module_put(entry->module);
435         kfree(data);
436         return 0;
437 }
438
439 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
440 {
441         struct snd_info_private_data *data;
442         struct snd_info_entry *entry;
443         unsigned int mask;
444
445         data = file->private_data;
446         if (data == NULL)
447                 return 0;
448         entry = data->entry;
449         mask = 0;
450         switch (entry->content) {
451         case SNDRV_INFO_CONTENT_DATA:
452                 if (entry->c.ops->poll)
453                         return entry->c.ops->poll(entry,
454                                                   data->file_private_data,
455                                                   file, wait);
456                 if (entry->c.ops->read)
457                         mask |= POLLIN | POLLRDNORM;
458                 if (entry->c.ops->write)
459                         mask |= POLLOUT | POLLWRNORM;
460                 break;
461         }
462         return mask;
463 }
464
465 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
466                                 unsigned long arg)
467 {
468         struct snd_info_private_data *data;
469         struct snd_info_entry *entry;
470
471         data = file->private_data;
472         if (data == NULL)
473                 return 0;
474         entry = data->entry;
475         switch (entry->content) {
476         case SNDRV_INFO_CONTENT_DATA:
477                 if (entry->c.ops->ioctl)
478                         return entry->c.ops->ioctl(entry,
479                                                    data->file_private_data,
480                                                    file, cmd, arg);
481                 break;
482         }
483         return -ENOTTY;
484 }
485
486 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
487 {
488         struct inode *inode = file->f_path.dentry->d_inode;
489         struct snd_info_private_data *data;
490         struct snd_info_entry *entry;
491
492         data = file->private_data;
493         if (data == NULL)
494                 return 0;
495         entry = data->entry;
496         switch (entry->content) {
497         case SNDRV_INFO_CONTENT_DATA:
498                 if (entry->c.ops->mmap)
499                         return entry->c.ops->mmap(entry,
500                                                   data->file_private_data,
501                                                   inode, file, vma);
502                 break;
503         }
504         return -ENXIO;
505 }
506
507 static const struct file_operations snd_info_entry_operations =
508 {
509         .owner =                THIS_MODULE,
510         .llseek =               snd_info_entry_llseek,
511         .read =                 snd_info_entry_read,
512         .write =                snd_info_entry_write,
513         .poll =                 snd_info_entry_poll,
514         .unlocked_ioctl =       snd_info_entry_ioctl,
515         .mmap =                 snd_info_entry_mmap,
516         .open =                 snd_info_entry_open,
517         .release =              snd_info_entry_release,
518 };
519
520 int __init snd_info_init(void)
521 {
522         struct proc_dir_entry *p;
523
524         p = create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
525         if (p == NULL)
526                 return -ENOMEM;
527         snd_proc_root = p;
528 #ifdef CONFIG_SND_OSSEMUL
529         {
530                 struct snd_info_entry *entry;
531                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
532                         return -ENOMEM;
533                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
534                 if (snd_info_register(entry) < 0) {
535                         snd_info_free_entry(entry);
536                         return -ENOMEM;
537                 }
538                 snd_oss_root = entry;
539         }
540 #endif
541 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
542         {
543                 struct snd_info_entry *entry;
544                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
545                         return -ENOMEM;
546                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
547                 if (snd_info_register(entry) < 0) {
548                         snd_info_free_entry(entry);
549                         return -ENOMEM;
550                 }
551                 snd_seq_root = entry;
552         }
553 #endif
554         snd_info_version_init();
555         snd_minor_info_init();
556         snd_minor_info_oss_init();
557         snd_card_info_init();
558         return 0;
559 }
560
561 int __exit snd_info_done(void)
562 {
563         snd_card_info_done();
564         snd_minor_info_oss_done();
565         snd_minor_info_done();
566         snd_info_version_done();
567         if (snd_proc_root) {
568 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
569                 snd_info_free_entry(snd_seq_root);
570 #endif
571 #ifdef CONFIG_SND_OSSEMUL
572                 snd_info_free_entry(snd_oss_root);
573 #endif
574                 snd_remove_proc_entry(NULL, snd_proc_root);
575         }
576         return 0;
577 }
578
579 /*
580
581  */
582
583
584 /*
585  * create a card proc file
586  * called from init.c
587  */
588 int snd_info_card_create(struct snd_card *card)
589 {
590         char str[8];
591         struct snd_info_entry *entry;
592
593         if (snd_BUG_ON(!card))
594                 return -ENXIO;
595
596         sprintf(str, "card%i", card->number);
597         if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
598                 return -ENOMEM;
599         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
600         if (snd_info_register(entry) < 0) {
601                 snd_info_free_entry(entry);
602                 return -ENOMEM;
603         }
604         card->proc_root = entry;
605         return 0;
606 }
607
608 /*
609  * register the card proc file
610  * called from init.c
611  */
612 int snd_info_card_register(struct snd_card *card)
613 {
614         struct proc_dir_entry *p;
615
616         if (snd_BUG_ON(!card))
617                 return -ENXIO;
618
619         if (!strcmp(card->id, card->proc_root->name))
620                 return 0;
621
622         p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
623         if (p == NULL)
624                 return -ENOMEM;
625         card->proc_root_link = p;
626         return 0;
627 }
628
629 /*
630  * called on card->id change
631  */
632 void snd_info_card_id_change(struct snd_card *card)
633 {
634         mutex_lock(&info_mutex);
635         if (card->proc_root_link) {
636                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
637                 card->proc_root_link = NULL;
638         }
639         if (strcmp(card->id, card->proc_root->name))
640                 card->proc_root_link = proc_symlink(card->id,
641                                                     snd_proc_root,
642                                                     card->proc_root->name);
643         mutex_unlock(&info_mutex);
644 }
645
646 /*
647  * de-register the card proc file
648  * called from init.c
649  */
650 void snd_info_card_disconnect(struct snd_card *card)
651 {
652         if (!card)
653                 return;
654         mutex_lock(&info_mutex);
655         if (card->proc_root_link) {
656                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
657                 card->proc_root_link = NULL;
658         }
659         if (card->proc_root)
660                 snd_info_disconnect(card->proc_root);
661         mutex_unlock(&info_mutex);
662 }
663
664 /*
665  * release the card proc file resources
666  * called from init.c
667  */
668 int snd_info_card_free(struct snd_card *card)
669 {
670         if (!card)
671                 return 0;
672         snd_info_free_entry(card->proc_root);
673         card->proc_root = NULL;
674         return 0;
675 }
676
677
678 /**
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
683  *
684  * Reads one line from the buffer and stores the string.
685  *
686  * Returns zero if successful, or 1 if error or EOF.
687  */
688 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
689 {
690         int c = -1;
691
692         if (len <= 0 || buffer->stop || buffer->error)
693                 return 1;
694         while (--len > 0) {
695                 c = buffer->buffer[buffer->curr++];
696                 if (c == '\n') {
697                         if (buffer->curr >= buffer->size)
698                                 buffer->stop = 1;
699                         break;
700                 }
701                 *line++ = c;
702                 if (buffer->curr >= buffer->size) {
703                         buffer->stop = 1;
704                         break;
705                 }
706         }
707         while (c != '\n' && !buffer->stop) {
708                 c = buffer->buffer[buffer->curr++];
709                 if (buffer->curr >= buffer->size)
710                         buffer->stop = 1;
711         }
712         *line = '\0';
713         return 0;
714 }
715
716 EXPORT_SYMBOL(snd_info_get_line);
717
718 /**
719  * snd_info_get_str - parse a string token
720  * @dest: the buffer to store the string token
721  * @src: the original string
722  * @len: the max. length of token - 1
723  *
724  * Parses the original string and copy a token to the given
725  * string buffer.
726  *
727  * Returns the updated pointer of the original string so that
728  * it can be used for the next call.
729  */
730 char *snd_info_get_str(char *dest, char *src, int len)
731 {
732         int c;
733
734         while (*src == ' ' || *src == '\t')
735                 src++;
736         if (*src == '"' || *src == '\'') {
737                 c = *src++;
738                 while (--len > 0 && *src && *src != c) {
739                         *dest++ = *src++;
740                 }
741                 if (*src == c)
742                         src++;
743         } else {
744                 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
745                         *dest++ = *src++;
746                 }
747         }
748         *dest = 0;
749         while (*src == ' ' || *src == '\t')
750                 src++;
751         return src;
752 }
753
754 EXPORT_SYMBOL(snd_info_get_str);
755
756 /**
757  * snd_info_create_entry - create an info entry
758  * @name: the proc file name
759  *
760  * Creates an info entry with the given file name and initializes as
761  * the default state.
762  *
763  * Usually called from other functions such as
764  * snd_info_create_card_entry().
765  *
766  * Returns the pointer of the new instance, or NULL on failure.
767  */
768 static struct snd_info_entry *snd_info_create_entry(const char *name)
769 {
770         struct snd_info_entry *entry;
771         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
772         if (entry == NULL)
773                 return NULL;
774         entry->name = kstrdup(name, GFP_KERNEL);
775         if (entry->name == NULL) {
776                 kfree(entry);
777                 return NULL;
778         }
779         entry->mode = S_IFREG | S_IRUGO;
780         entry->content = SNDRV_INFO_CONTENT_TEXT;
781         mutex_init(&entry->access);
782         INIT_LIST_HEAD(&entry->children);
783         INIT_LIST_HEAD(&entry->list);
784         return entry;
785 }
786
787 /**
788  * snd_info_create_module_entry - create an info entry for the given module
789  * @module: the module pointer
790  * @name: the file name
791  * @parent: the parent directory
792  *
793  * Creates a new info entry and assigns it to the given module.
794  *
795  * Returns the pointer of the new instance, or NULL on failure.
796  */
797 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
798                                                const char *name,
799                                                struct snd_info_entry *parent)
800 {
801         struct snd_info_entry *entry = snd_info_create_entry(name);
802         if (entry) {
803                 entry->module = module;
804                 entry->parent = parent;
805         }
806         return entry;
807 }
808
809 EXPORT_SYMBOL(snd_info_create_module_entry);
810
811 /**
812  * snd_info_create_card_entry - create an info entry for the given card
813  * @card: the card instance
814  * @name: the file name
815  * @parent: the parent directory
816  *
817  * Creates a new info entry and assigns it to the given card.
818  *
819  * Returns the pointer of the new instance, or NULL on failure.
820  */
821 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
822                                              const char *name,
823                                              struct snd_info_entry * parent)
824 {
825         struct snd_info_entry *entry = snd_info_create_entry(name);
826         if (entry) {
827                 entry->module = card->module;
828                 entry->card = card;
829                 entry->parent = parent;
830         }
831         return entry;
832 }
833
834 EXPORT_SYMBOL(snd_info_create_card_entry);
835
836 static void snd_info_disconnect(struct snd_info_entry *entry)
837 {
838         struct list_head *p, *n;
839         struct proc_dir_entry *root;
840
841         list_for_each_safe(p, n, &entry->children) {
842                 snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
843         }
844
845         if (! entry->p)
846                 return;
847         list_del_init(&entry->list);
848         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
849         snd_BUG_ON(!root);
850         snd_remove_proc_entry(root, entry->p);
851         entry->p = NULL;
852 }
853
854 static int snd_info_dev_free_entry(struct snd_device *device)
855 {
856         struct snd_info_entry *entry = device->device_data;
857         snd_info_free_entry(entry);
858         return 0;
859 }
860
861 static int snd_info_dev_register_entry(struct snd_device *device)
862 {
863         struct snd_info_entry *entry = device->device_data;
864         return snd_info_register(entry);
865 }
866
867 /**
868  * snd_card_proc_new - create an info entry for the given card
869  * @card: the card instance
870  * @name: the file name
871  * @entryp: the pointer to store the new info entry
872  *
873  * Creates a new info entry and assigns it to the given card.
874  * Unlike snd_info_create_card_entry(), this function registers the
875  * info entry as an ALSA device component, so that it can be
876  * unregistered/released without explicit call.
877  * Also, you don't have to register this entry via snd_info_register(),
878  * since this will be registered by snd_card_register() automatically.
879  *
880  * The parent is assumed as card->proc_root.
881  *
882  * For releasing this entry, use snd_device_free() instead of
883  * snd_info_free_entry(). 
884  *
885  * Returns zero if successful, or a negative error code on failure.
886  */
887 int snd_card_proc_new(struct snd_card *card, const char *name,
888                       struct snd_info_entry **entryp)
889 {
890         static struct snd_device_ops ops = {
891                 .dev_free = snd_info_dev_free_entry,
892                 .dev_register = snd_info_dev_register_entry,
893                 /* disconnect is done via snd_info_card_disconnect() */
894         };
895         struct snd_info_entry *entry;
896         int err;
897
898         entry = snd_info_create_card_entry(card, name, card->proc_root);
899         if (! entry)
900                 return -ENOMEM;
901         if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
902                 snd_info_free_entry(entry);
903                 return err;
904         }
905         if (entryp)
906                 *entryp = entry;
907         return 0;
908 }
909
910 EXPORT_SYMBOL(snd_card_proc_new);
911
912 /**
913  * snd_info_free_entry - release the info entry
914  * @entry: the info entry
915  *
916  * Releases the info entry.  Don't call this after registered.
917  */
918 void snd_info_free_entry(struct snd_info_entry * entry)
919 {
920         if (entry == NULL)
921                 return;
922         if (entry->p) {
923                 mutex_lock(&info_mutex);
924                 snd_info_disconnect(entry);
925                 mutex_unlock(&info_mutex);
926         }
927         kfree(entry->name);
928         if (entry->private_free)
929                 entry->private_free(entry);
930         kfree(entry);
931 }
932
933 EXPORT_SYMBOL(snd_info_free_entry);
934
935 /**
936  * snd_info_register - register the info entry
937  * @entry: the info entry
938  *
939  * Registers the proc info entry.
940  *
941  * Returns zero if successful, or a negative error code on failure.
942  */
943 int snd_info_register(struct snd_info_entry * entry)
944 {
945         struct proc_dir_entry *root, *p = NULL;
946
947         if (snd_BUG_ON(!entry))
948                 return -ENXIO;
949         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
950         mutex_lock(&info_mutex);
951         p = create_proc_entry(entry->name, entry->mode, root);
952         if (!p) {
953                 mutex_unlock(&info_mutex);
954                 return -ENOMEM;
955         }
956         if (!S_ISDIR(entry->mode))
957                 p->proc_fops = &snd_info_entry_operations;
958         p->size = entry->size;
959         p->data = entry;
960         entry->p = p;
961         if (entry->parent)
962                 list_add_tail(&entry->list, &entry->parent->children);
963         mutex_unlock(&info_mutex);
964         return 0;
965 }
966
967 EXPORT_SYMBOL(snd_info_register);
968
969 /*
970
971  */
972
973 static struct snd_info_entry *snd_info_version_entry;
974
975 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
976 {
977         snd_iprintf(buffer,
978                     "Advanced Linux Sound Architecture Driver Version "
979                     CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
980                    );
981 }
982
983 static int __init snd_info_version_init(void)
984 {
985         struct snd_info_entry *entry;
986
987         entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
988         if (entry == NULL)
989                 return -ENOMEM;
990         entry->c.text.read = snd_info_version_read;
991         if (snd_info_register(entry) < 0) {
992                 snd_info_free_entry(entry);
993                 return -ENOMEM;
994         }
995         snd_info_version_entry = entry;
996         return 0;
997 }
998
999 static int __exit snd_info_version_done(void)
1000 {
1001         snd_info_free_entry(snd_info_version_entry);
1002         return 0;
1003 }
1004
1005 #endif /* CONFIG_PROC_FS */