[PATCH] devfs: Remove devfs support from the sound subsystem
[linux-2.6.git] / sound / core / info.c
1 /*
2  *  Information interface for ALSA driver
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
23 #include <linux/init.h>
24 #include <linux/time.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
82
83 /* resize the proc r/w buffer */
84 static int resize_info_buffer(struct snd_info_buffer *buffer,
85                               unsigned int nsize)
86 {
87         char *nbuf;
88
89         nsize = PAGE_ALIGN(nsize);
90         nbuf = kmalloc(nsize, GFP_KERNEL);
91         if (! nbuf)
92                 return -ENOMEM;
93
94         memcpy(nbuf, buffer->buffer, buffer->len);
95         kfree(buffer->buffer);
96         buffer->buffer = nbuf;
97         buffer->len = nsize;
98         return 0;
99 }
100
101 /**
102  * snd_iprintf - printf on the procfs buffer
103  * @buffer: the procfs buffer
104  * @fmt: the printf format
105  *
106  * Outputs the string on the procfs buffer just like printf().
107  *
108  * Returns the size of output string.
109  */
110 int snd_iprintf(struct snd_info_buffer *buffer, char *fmt,...)
111 {
112         va_list args;
113         int len, res;
114         int err = 0;
115
116         might_sleep();
117         if (buffer->stop || buffer->error)
118                 return 0;
119         len = buffer->len - buffer->size;
120         va_start(args, fmt);
121         for (;;) {
122                 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, args);
123                 if (res < len)
124                         break;
125                 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
126                 if (err < 0)
127                         break;
128                 len = buffer->len - buffer->size;
129         }
130         va_end(args);
131
132         if (err < 0)
133                 return err;
134         buffer->curr += res;
135         buffer->size += res;
136         return res;
137 }
138
139 EXPORT_SYMBOL(snd_iprintf);
140
141 /*
142
143  */
144
145 static struct proc_dir_entry *snd_proc_root;
146 struct snd_info_entry *snd_seq_root;
147 EXPORT_SYMBOL(snd_seq_root);
148
149 #ifdef CONFIG_SND_OSSEMUL
150 struct snd_info_entry *snd_oss_root;
151 #endif
152
153 static inline void snd_info_entry_prepare(struct proc_dir_entry *de)
154 {
155         de->owner = THIS_MODULE;
156 }
157
158 static void snd_remove_proc_entry(struct proc_dir_entry *parent,
159                                   struct proc_dir_entry *de)
160 {
161         if (de)
162                 remove_proc_entry(de->name, parent);
163 }
164
165 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
166 {
167         struct snd_info_private_data *data;
168         struct snd_info_entry *entry;
169         loff_t ret;
170
171         data = file->private_data;
172         entry = data->entry;
173         lock_kernel();
174         switch (entry->content) {
175         case SNDRV_INFO_CONTENT_TEXT:
176                 switch (orig) {
177                 case 0: /* SEEK_SET */
178                         file->f_pos = offset;
179                         ret = file->f_pos;
180                         goto out;
181                 case 1: /* SEEK_CUR */
182                         file->f_pos += offset;
183                         ret = file->f_pos;
184                         goto out;
185                 case 2: /* SEEK_END */
186                 default:
187                         ret = -EINVAL;
188                         goto out;
189                 }
190                 break;
191         case SNDRV_INFO_CONTENT_DATA:
192                 if (entry->c.ops->llseek) {
193                         ret = entry->c.ops->llseek(entry,
194                                                     data->file_private_data,
195                                                     file, offset, orig);
196                         goto out;
197                 }
198                 break;
199         }
200         ret = -ENXIO;
201 out:
202         unlock_kernel();
203         return ret;
204 }
205
206 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
207                                    size_t count, loff_t * offset)
208 {
209         struct snd_info_private_data *data;
210         struct snd_info_entry *entry;
211         struct snd_info_buffer *buf;
212         size_t size = 0;
213         loff_t pos;
214
215         data = file->private_data;
216         snd_assert(data != NULL, 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         snd_assert(data != NULL, return -ENXIO);
258         entry = data->entry;
259         pos = *offset;
260         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
261                 return -EIO;
262         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
263                 return -EIO;
264         switch (entry->content) {
265         case SNDRV_INFO_CONTENT_TEXT:
266                 buf = data->wbuffer;
267                 if (buf == NULL)
268                         return -EIO;
269                 mutex_lock(&entry->access);
270                 if (pos + count >= buf->len) {
271                         if (resize_info_buffer(buf, pos + count)) {
272                                 mutex_unlock(&entry->access);
273                                 return -ENOMEM;
274                         }
275                 }
276                 if (copy_from_user(buf->buffer + pos, buffer, count)) {
277                         mutex_unlock(&entry->access);
278                         return -EFAULT;
279                 }
280                 buf->size = pos + count;
281                 mutex_unlock(&entry->access);
282                 size = count;
283                 break;
284         case SNDRV_INFO_CONTENT_DATA:
285                 if (entry->c.ops->write)
286                         size = entry->c.ops->write(entry,
287                                                    data->file_private_data,
288                                                    file, buffer, count, pos);
289                 break;
290         }
291         if ((ssize_t) size > 0)
292                 *offset = pos + size;
293         return size;
294 }
295
296 static int snd_info_entry_open(struct inode *inode, struct file *file)
297 {
298         struct snd_info_entry *entry;
299         struct snd_info_private_data *data;
300         struct snd_info_buffer *buffer;
301         struct proc_dir_entry *p;
302         int mode, err;
303
304         mutex_lock(&info_mutex);
305         p = PDE(inode);
306         entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
307         if (entry == NULL || entry->disconnected) {
308                 mutex_unlock(&info_mutex);
309                 return -ENODEV;
310         }
311         if (!try_module_get(entry->module)) {
312                 err = -EFAULT;
313                 goto __error1;
314         }
315         mode = file->f_flags & O_ACCMODE;
316         if (mode == O_RDONLY || mode == O_RDWR) {
317                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
318                      entry->c.ops->read == NULL)) {
319                         err = -ENODEV;
320                         goto __error;
321                 }
322         }
323         if (mode == O_WRONLY || mode == O_RDWR) {
324                 if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
325                      entry->c.ops->write == NULL)) {
326                         err = -ENODEV;
327                         goto __error;
328                 }
329         }
330         data = kzalloc(sizeof(*data), GFP_KERNEL);
331         if (data == NULL) {
332                 err = -ENOMEM;
333                 goto __error;
334         }
335         data->entry = entry;
336         switch (entry->content) {
337         case SNDRV_INFO_CONTENT_TEXT:
338                 if (mode == O_RDONLY || mode == O_RDWR) {
339                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
340                         if (buffer == NULL)
341                                 goto __nomem;
342                         data->rbuffer = buffer;
343                         buffer->len = PAGE_SIZE;
344                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
345                         if (buffer->buffer == NULL)
346                                 goto __nomem;
347                 }
348                 if (mode == O_WRONLY || mode == O_RDWR) {
349                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
350                         if (buffer == NULL)
351                                 goto __nomem;
352                         data->wbuffer = buffer;
353                         buffer->len = PAGE_SIZE;
354                         buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
355                         if (buffer->buffer == NULL)
356                                 goto __nomem;
357                 }
358                 break;
359         case SNDRV_INFO_CONTENT_DATA:   /* data */
360                 if (entry->c.ops->open) {
361                         if ((err = entry->c.ops->open(entry, mode,
362                                                       &data->file_private_data)) < 0) {
363                                 kfree(data);
364                                 goto __error;
365                         }
366                 }
367                 break;
368         }
369         file->private_data = data;
370         mutex_unlock(&info_mutex);
371         if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
372             (mode == O_RDONLY || mode == O_RDWR)) {
373                 if (entry->c.text.read) {
374                         mutex_lock(&entry->access);
375                         entry->c.text.read(entry, data->rbuffer);
376                         mutex_unlock(&entry->access);
377                 }
378         }
379         return 0;
380
381  __nomem:
382         if (data->rbuffer) {
383                 kfree(data->rbuffer->buffer);
384                 kfree(data->rbuffer);
385         }
386         if (data->wbuffer) {
387                 kfree(data->wbuffer->buffer);
388                 kfree(data->wbuffer);
389         }
390         kfree(data);
391         err = -ENOMEM;
392       __error:
393         module_put(entry->module);
394       __error1:
395         mutex_unlock(&info_mutex);
396         return err;
397 }
398
399 static int snd_info_entry_release(struct inode *inode, struct file *file)
400 {
401         struct snd_info_entry *entry;
402         struct snd_info_private_data *data;
403         int mode;
404
405         mode = file->f_flags & O_ACCMODE;
406         data = file->private_data;
407         entry = data->entry;
408         switch (entry->content) {
409         case SNDRV_INFO_CONTENT_TEXT:
410                 if (data->rbuffer) {
411                         kfree(data->rbuffer->buffer);
412                         kfree(data->rbuffer);
413                 }
414                 if (data->wbuffer) {
415                         if (entry->c.text.write) {
416                                 entry->c.text.write(entry, data->wbuffer);
417                                 if (data->wbuffer->error) {
418                                         snd_printk(KERN_WARNING "data write error to %s (%i)\n",
419                                                 entry->name,
420                                                 data->wbuffer->error);
421                                 }
422                         }
423                         kfree(data->wbuffer->buffer);
424                         kfree(data->wbuffer);
425                 }
426                 break;
427         case SNDRV_INFO_CONTENT_DATA:
428                 if (entry->c.ops->release)
429                         entry->c.ops->release(entry, mode,
430                                               data->file_private_data);
431                 break;
432         }
433         module_put(entry->module);
434         kfree(data);
435         return 0;
436 }
437
438 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
439 {
440         struct snd_info_private_data *data;
441         struct snd_info_entry *entry;
442         unsigned int mask;
443
444         data = file->private_data;
445         if (data == NULL)
446                 return 0;
447         entry = data->entry;
448         mask = 0;
449         switch (entry->content) {
450         case SNDRV_INFO_CONTENT_DATA:
451                 if (entry->c.ops->poll)
452                         return entry->c.ops->poll(entry,
453                                                   data->file_private_data,
454                                                   file, wait);
455                 if (entry->c.ops->read)
456                         mask |= POLLIN | POLLRDNORM;
457                 if (entry->c.ops->write)
458                         mask |= POLLOUT | POLLWRNORM;
459                 break;
460         }
461         return mask;
462 }
463
464 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
465                                 unsigned long arg)
466 {
467         struct snd_info_private_data *data;
468         struct snd_info_entry *entry;
469
470         data = file->private_data;
471         if (data == NULL)
472                 return 0;
473         entry = data->entry;
474         switch (entry->content) {
475         case SNDRV_INFO_CONTENT_DATA:
476                 if (entry->c.ops->ioctl)
477                         return entry->c.ops->ioctl(entry,
478                                                    data->file_private_data,
479                                                    file, cmd, arg);
480                 break;
481         }
482         return -ENOTTY;
483 }
484
485 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
486 {
487         struct inode *inode = file->f_dentry->d_inode;
488         struct snd_info_private_data *data;
489         struct snd_info_entry *entry;
490
491         data = file->private_data;
492         if (data == NULL)
493                 return 0;
494         entry = data->entry;
495         switch (entry->content) {
496         case SNDRV_INFO_CONTENT_DATA:
497                 if (entry->c.ops->mmap)
498                         return entry->c.ops->mmap(entry,
499                                                   data->file_private_data,
500                                                   inode, file, vma);
501                 break;
502         }
503         return -ENXIO;
504 }
505
506 static struct file_operations snd_info_entry_operations =
507 {
508         .owner =                THIS_MODULE,
509         .llseek =               snd_info_entry_llseek,
510         .read =                 snd_info_entry_read,
511         .write =                snd_info_entry_write,
512         .poll =                 snd_info_entry_poll,
513         .unlocked_ioctl =       snd_info_entry_ioctl,
514         .mmap =                 snd_info_entry_mmap,
515         .open =                 snd_info_entry_open,
516         .release =              snd_info_entry_release,
517 };
518
519 /**
520  * snd_create_proc_entry - create a procfs entry
521  * @name: the name of the proc file
522  * @mode: the file permission bits, S_Ixxx
523  * @parent: the parent proc-directory entry
524  *
525  * Creates a new proc file entry with the given name and permission
526  * on the given directory.
527  *
528  * Returns the pointer of new instance or NULL on failure.
529  */
530 static struct proc_dir_entry *snd_create_proc_entry(const char *name, mode_t mode,
531                                                     struct proc_dir_entry *parent)
532 {
533         struct proc_dir_entry *p;
534         p = create_proc_entry(name, mode, parent);
535         if (p)
536                 snd_info_entry_prepare(p);
537         return p;
538 }
539
540 int __init snd_info_init(void)
541 {
542         struct proc_dir_entry *p;
543
544         p = snd_create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, &proc_root);
545         if (p == NULL)
546                 return -ENOMEM;
547         snd_proc_root = p;
548 #ifdef CONFIG_SND_OSSEMUL
549         {
550                 struct snd_info_entry *entry;
551                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
552                         return -ENOMEM;
553                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
554                 if (snd_info_register(entry) < 0) {
555                         snd_info_free_entry(entry);
556                         return -ENOMEM;
557                 }
558                 snd_oss_root = entry;
559         }
560 #endif
561 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
562         {
563                 struct snd_info_entry *entry;
564                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
565                         return -ENOMEM;
566                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
567                 if (snd_info_register(entry) < 0) {
568                         snd_info_free_entry(entry);
569                         return -ENOMEM;
570                 }
571                 snd_seq_root = entry;
572         }
573 #endif
574         snd_info_version_init();
575         snd_minor_info_init();
576         snd_minor_info_oss_init();
577         snd_card_info_init();
578         return 0;
579 }
580
581 int __exit snd_info_done(void)
582 {
583         snd_card_info_done();
584         snd_minor_info_oss_done();
585         snd_minor_info_done();
586         snd_info_version_done();
587         if (snd_proc_root) {
588 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
589                 snd_info_unregister(snd_seq_root);
590 #endif
591 #ifdef CONFIG_SND_OSSEMUL
592                 snd_info_unregister(snd_oss_root);
593 #endif
594                 snd_remove_proc_entry(&proc_root, snd_proc_root);
595         }
596         return 0;
597 }
598
599 /*
600
601  */
602
603
604 /*
605  * create a card proc file
606  * called from init.c
607  */
608 int snd_info_card_create(struct snd_card *card)
609 {
610         char str[8];
611         struct snd_info_entry *entry;
612
613         snd_assert(card != NULL, return -ENXIO);
614
615         sprintf(str, "card%i", card->number);
616         if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
617                 return -ENOMEM;
618         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
619         if (snd_info_register(entry) < 0) {
620                 snd_info_free_entry(entry);
621                 return -ENOMEM;
622         }
623         card->proc_root = entry;
624         return 0;
625 }
626
627 /*
628  * register the card proc file
629  * called from init.c
630  */
631 int snd_info_card_register(struct snd_card *card)
632 {
633         struct proc_dir_entry *p;
634
635         snd_assert(card != NULL, return -ENXIO);
636
637         if (!strcmp(card->id, card->proc_root->name))
638                 return 0;
639
640         p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
641         if (p == NULL)
642                 return -ENOMEM;
643         card->proc_root_link = p;
644         return 0;
645 }
646
647 /*
648  * de-register the card proc file
649  * called from init.c
650  */
651 int snd_info_card_free(struct snd_card *card)
652 {
653         snd_assert(card != NULL, return -ENXIO);
654         if (card->proc_root_link) {
655                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
656                 card->proc_root_link = NULL;
657         }
658         if (card->proc_root) {
659                 snd_info_unregister(card->proc_root);
660                 card->proc_root = NULL;
661         }
662         return 0;
663 }
664
665
666 /**
667  * snd_info_get_line - read one line from the procfs buffer
668  * @buffer: the procfs buffer
669  * @line: the buffer to store
670  * @len: the max. buffer size - 1
671  *
672  * Reads one line from the buffer and stores the string.
673  *
674  * Returns zero if successful, or 1 if error or EOF.
675  */
676 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
677 {
678         int c = -1;
679
680         if (len <= 0 || buffer->stop || buffer->error)
681                 return 1;
682         while (--len > 0) {
683                 c = buffer->buffer[buffer->curr++];
684                 if (c == '\n') {
685                         if (buffer->curr >= buffer->size)
686                                 buffer->stop = 1;
687                         break;
688                 }
689                 *line++ = c;
690                 if (buffer->curr >= buffer->size) {
691                         buffer->stop = 1;
692                         break;
693                 }
694         }
695         while (c != '\n' && !buffer->stop) {
696                 c = buffer->buffer[buffer->curr++];
697                 if (buffer->curr >= buffer->size)
698                         buffer->stop = 1;
699         }
700         *line = '\0';
701         return 0;
702 }
703
704 EXPORT_SYMBOL(snd_info_get_line);
705
706 /**
707  * snd_info_get_str - parse a string token
708  * @dest: the buffer to store the string token
709  * @src: the original string
710  * @len: the max. length of token - 1
711  *
712  * Parses the original string and copy a token to the given
713  * string buffer.
714  *
715  * Returns the updated pointer of the original string so that
716  * it can be used for the next call.
717  */
718 char *snd_info_get_str(char *dest, char *src, int len)
719 {
720         int c;
721
722         while (*src == ' ' || *src == '\t')
723                 src++;
724         if (*src == '"' || *src == '\'') {
725                 c = *src++;
726                 while (--len > 0 && *src && *src != c) {
727                         *dest++ = *src++;
728                 }
729                 if (*src == c)
730                         src++;
731         } else {
732                 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
733                         *dest++ = *src++;
734                 }
735         }
736         *dest = 0;
737         while (*src == ' ' || *src == '\t')
738                 src++;
739         return src;
740 }
741
742 EXPORT_SYMBOL(snd_info_get_str);
743
744 /**
745  * snd_info_create_entry - create an info entry
746  * @name: the proc file name
747  *
748  * Creates an info entry with the given file name and initializes as
749  * the default state.
750  *
751  * Usually called from other functions such as
752  * snd_info_create_card_entry().
753  *
754  * Returns the pointer of the new instance, or NULL on failure.
755  */
756 static struct snd_info_entry *snd_info_create_entry(const char *name)
757 {
758         struct snd_info_entry *entry;
759         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
760         if (entry == NULL)
761                 return NULL;
762         entry->name = kstrdup(name, GFP_KERNEL);
763         if (entry->name == NULL) {
764                 kfree(entry);
765                 return NULL;
766         }
767         entry->mode = S_IFREG | S_IRUGO;
768         entry->content = SNDRV_INFO_CONTENT_TEXT;
769         mutex_init(&entry->access);
770         return entry;
771 }
772
773 /**
774  * snd_info_create_module_entry - create an info entry for the given module
775  * @module: the module pointer
776  * @name: the file name
777  * @parent: the parent directory
778  *
779  * Creates a new info entry and assigns it to the given module.
780  *
781  * Returns the pointer of the new instance, or NULL on failure.
782  */
783 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
784                                                const char *name,
785                                                struct snd_info_entry *parent)
786 {
787         struct snd_info_entry *entry = snd_info_create_entry(name);
788         if (entry) {
789                 entry->module = module;
790                 entry->parent = parent;
791         }
792         return entry;
793 }
794
795 EXPORT_SYMBOL(snd_info_create_module_entry);
796
797 /**
798  * snd_info_create_card_entry - create an info entry for the given card
799  * @card: the card instance
800  * @name: the file name
801  * @parent: the parent directory
802  *
803  * Creates a new info entry and assigns it to the given card.
804  *
805  * Returns the pointer of the new instance, or NULL on failure.
806  */
807 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
808                                              const char *name,
809                                              struct snd_info_entry * parent)
810 {
811         struct snd_info_entry *entry = snd_info_create_entry(name);
812         if (entry) {
813                 entry->module = card->module;
814                 entry->card = card;
815                 entry->parent = parent;
816         }
817         return entry;
818 }
819
820 EXPORT_SYMBOL(snd_info_create_card_entry);
821
822 static int snd_info_dev_free_entry(struct snd_device *device)
823 {
824         struct snd_info_entry *entry = device->device_data;
825         snd_info_free_entry(entry);
826         return 0;
827 }
828
829 static int snd_info_dev_register_entry(struct snd_device *device)
830 {
831         struct snd_info_entry *entry = device->device_data;
832         return snd_info_register(entry);
833 }
834
835 static int snd_info_dev_disconnect_entry(struct snd_device *device)
836 {
837         struct snd_info_entry *entry = device->device_data;
838         entry->disconnected = 1;
839         return 0;
840 }
841
842 static int snd_info_dev_unregister_entry(struct snd_device *device)
843 {
844         struct snd_info_entry *entry = device->device_data;
845         return snd_info_unregister(entry);
846 }
847
848 /**
849  * snd_card_proc_new - create an info entry for the given card
850  * @card: the card instance
851  * @name: the file name
852  * @entryp: the pointer to store the new info entry
853  *
854  * Creates a new info entry and assigns it to the given card.
855  * Unlike snd_info_create_card_entry(), this function registers the
856  * info entry as an ALSA device component, so that it can be
857  * unregistered/released without explicit call.
858  * Also, you don't have to register this entry via snd_info_register(),
859  * since this will be registered by snd_card_register() automatically.
860  *
861  * The parent is assumed as card->proc_root.
862  *
863  * For releasing this entry, use snd_device_free() instead of
864  * snd_info_free_entry(). 
865  *
866  * Returns zero if successful, or a negative error code on failure.
867  */
868 int snd_card_proc_new(struct snd_card *card, const char *name,
869                       struct snd_info_entry **entryp)
870 {
871         static struct snd_device_ops ops = {
872                 .dev_free = snd_info_dev_free_entry,
873                 .dev_register = snd_info_dev_register_entry,
874                 .dev_disconnect = snd_info_dev_disconnect_entry,
875                 .dev_unregister = snd_info_dev_unregister_entry
876         };
877         struct snd_info_entry *entry;
878         int err;
879
880         entry = snd_info_create_card_entry(card, name, card->proc_root);
881         if (! entry)
882                 return -ENOMEM;
883         if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
884                 snd_info_free_entry(entry);
885                 return err;
886         }
887         if (entryp)
888                 *entryp = entry;
889         return 0;
890 }
891
892 EXPORT_SYMBOL(snd_card_proc_new);
893
894 /**
895  * snd_info_free_entry - release the info entry
896  * @entry: the info entry
897  *
898  * Releases the info entry.  Don't call this after registered.
899  */
900 void snd_info_free_entry(struct snd_info_entry * entry)
901 {
902         if (entry == NULL)
903                 return;
904         kfree(entry->name);
905         if (entry->private_free)
906                 entry->private_free(entry);
907         kfree(entry);
908 }
909
910 EXPORT_SYMBOL(snd_info_free_entry);
911
912 /**
913  * snd_info_register - register the info entry
914  * @entry: the info entry
915  *
916  * Registers the proc info entry.
917  *
918  * Returns zero if successful, or a negative error code on failure.
919  */
920 int snd_info_register(struct snd_info_entry * entry)
921 {
922         struct proc_dir_entry *root, *p = NULL;
923
924         snd_assert(entry != NULL, return -ENXIO);
925         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
926         mutex_lock(&info_mutex);
927         p = snd_create_proc_entry(entry->name, entry->mode, root);
928         if (!p) {
929                 mutex_unlock(&info_mutex);
930                 return -ENOMEM;
931         }
932         p->owner = entry->module;
933         if (!S_ISDIR(entry->mode))
934                 p->proc_fops = &snd_info_entry_operations;
935         p->size = entry->size;
936         p->data = entry;
937         entry->p = p;
938         mutex_unlock(&info_mutex);
939         return 0;
940 }
941
942 EXPORT_SYMBOL(snd_info_register);
943
944 /**
945  * snd_info_unregister - de-register the info entry
946  * @entry: the info entry
947  *
948  * De-registers the info entry and releases the instance.
949  *
950  * Returns zero if successful, or a negative error code on failure.
951  */
952 int snd_info_unregister(struct snd_info_entry * entry)
953 {
954         struct proc_dir_entry *root;
955
956         if (! entry)
957                 return 0;
958         snd_assert(entry->p != NULL, return -ENXIO);
959         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
960         snd_assert(root, return -ENXIO);
961         mutex_lock(&info_mutex);
962         snd_remove_proc_entry(root, entry->p);
963         mutex_unlock(&info_mutex);
964         snd_info_free_entry(entry);
965         return 0;
966 }
967
968 EXPORT_SYMBOL(snd_info_unregister);
969
970 /*
971
972  */
973
974 static struct snd_info_entry *snd_info_version_entry;
975
976 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
977 {
978         snd_iprintf(buffer,
979                     "Advanced Linux Sound Architecture Driver Version "
980                     CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
981                    );
982 }
983
984 static int __init snd_info_version_init(void)
985 {
986         struct snd_info_entry *entry;
987
988         entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
989         if (entry == NULL)
990                 return -ENOMEM;
991         entry->c.text.read = snd_info_version_read;
992         if (snd_info_register(entry) < 0) {
993                 snd_info_free_entry(entry);
994                 return -ENOMEM;
995         }
996         snd_info_version_entry = entry;
997         return 0;
998 }
999
1000 static int __exit snd_info_version_done(void)
1001 {
1002         if (snd_info_version_entry)
1003                 snd_info_unregister(snd_info_version_entry);
1004         return 0;
1005 }
1006
1007 #endif /* CONFIG_PROC_FS */