Linux Audio

Check our new training course

Loading...
v4.17
  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/slab.h>
 26#include <linux/string.h>
 27#include <linux/module.h>
 28#include <sound/core.h>
 29#include <sound/minors.h>
 30#include <sound/info.h>
 31#include <linux/utsname.h>
 32#include <linux/proc_fs.h>
 33#include <linux/mutex.h>
 34#include <stdarg.h>
 35
 
 
 
 
 
 
 36int snd_info_check_reserved_words(const char *str)
 37{
 38	static char *reserved[] =
 39	{
 40		"version",
 41		"meminfo",
 42		"memdebug",
 43		"detect",
 44		"devices",
 45		"oss",
 46		"cards",
 47		"timers",
 48		"synth",
 49		"pcm",
 50		"seq",
 51		NULL
 52	};
 53	char **xstr = reserved;
 54
 55	while (*xstr) {
 56		if (!strcmp(*xstr, str))
 57			return 0;
 58		xstr++;
 59	}
 60	if (!strncmp(str, "card", 4))
 61		return 0;
 62	return 1;
 63}
 64
 65static DEFINE_MUTEX(info_mutex);
 66
 67struct snd_info_private_data {
 68	struct snd_info_buffer *rbuffer;
 69	struct snd_info_buffer *wbuffer;
 70	struct snd_info_entry *entry;
 71	void *file_private_data;
 72};
 73
 74static int snd_info_version_init(void);
 
 75static void snd_info_disconnect(struct snd_info_entry *entry);
 76
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 77/*
 78
 79 */
 80
 81static struct snd_info_entry *snd_proc_root;
 82struct snd_info_entry *snd_seq_root;
 83EXPORT_SYMBOL(snd_seq_root);
 84
 85#ifdef CONFIG_SND_OSSEMUL
 86struct snd_info_entry *snd_oss_root;
 87#endif
 88
 89static int alloc_info_private(struct snd_info_entry *entry,
 90			      struct snd_info_private_data **ret)
 91{
 92	struct snd_info_private_data *data;
 93
 94	if (!entry || !entry->p)
 95		return -ENODEV;
 96	if (!try_module_get(entry->module))
 97		return -EFAULT;
 98	data = kzalloc(sizeof(*data), GFP_KERNEL);
 99	if (!data) {
100		module_put(entry->module);
101		return -ENOMEM;
102	}
103	data->entry = entry;
104	*ret = data;
105	return 0;
106}
107
108static bool valid_pos(loff_t pos, size_t count)
109{
110	if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
111		return false;
112	if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
113		return false;
114	return true;
115}
116
117/*
118 * file ops for binary proc files
119 */
120static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
121{
122	struct snd_info_private_data *data;
123	struct snd_info_entry *entry;
124	loff_t ret = -EINVAL, size;
125
126	data = file->private_data;
127	entry = data->entry;
128	mutex_lock(&entry->access);
129	if (entry->c.ops->llseek) {
 
130		offset = entry->c.ops->llseek(entry,
131					      data->file_private_data,
132					      file, offset, orig);
133		goto out;
134	}
135
136	size = entry->size;
 
 
137	switch (orig) {
138	case SEEK_SET:
139		break;
140	case SEEK_CUR:
141		offset += file->f_pos;
142		break;
143	case SEEK_END:
144		if (!size)
145			goto out;
146		offset += size;
147		break;
148	default:
149		goto out;
150	}
151	if (offset < 0)
152		goto out;
153	if (size && offset > size)
154		offset = size;
155	file->f_pos = offset;
156	ret = offset;
157 out:
158	mutex_unlock(&entry->access);
159	return ret;
160}
161
162static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
163				   size_t count, loff_t * offset)
164{
165	struct snd_info_private_data *data = file->private_data;
166	struct snd_info_entry *entry = data->entry;
167	size_t size;
 
168	loff_t pos;
169
 
 
 
170	pos = *offset;
171	if (!valid_pos(pos, count))
172		return -EIO;
173	if (pos >= entry->size)
174		return 0;
175	size = entry->size - pos;
176	size = min(count, size);
177	size = entry->c.ops->read(entry, data->file_private_data,
178				  file, buffer, size, pos);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
179	if ((ssize_t) size > 0)
180		*offset = pos + size;
181	return size;
182}
183
184static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
185				    size_t count, loff_t * offset)
186{
187	struct snd_info_private_data *data = file->private_data;
188	struct snd_info_entry *entry = data->entry;
 
189	ssize_t size = 0;
190	loff_t pos;
191
 
 
 
 
192	pos = *offset;
193	if (!valid_pos(pos, count))
194		return -EIO;
195	if (count > 0) {
196		size_t maxsize = entry->size - pos;
197		count = min(count, maxsize);
198		size = entry->c.ops->write(entry, data->file_private_data,
199					   file, buffer, count, pos);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
200	}
201	if (size > 0)
202		*offset = pos + size;
203	return size;
204}
205
206static __poll_t snd_info_entry_poll(struct file *file, poll_table *wait)
207{
208	struct snd_info_private_data *data = file->private_data;
209	struct snd_info_entry *entry = data->entry;
210	__poll_t mask = 0;
211
212	if (entry->c.ops->poll)
213		return entry->c.ops->poll(entry,
214					  data->file_private_data,
215					  file, wait);
216	if (entry->c.ops->read)
217		mask |= EPOLLIN | EPOLLRDNORM;
218	if (entry->c.ops->write)
219		mask |= EPOLLOUT | EPOLLWRNORM;
220	return mask;
221}
222
223static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
224				unsigned long arg)
225{
226	struct snd_info_private_data *data = file->private_data;
227	struct snd_info_entry *entry = data->entry;
228
229	if (!entry->c.ops->ioctl)
230		return -ENOTTY;
231	return entry->c.ops->ioctl(entry, data->file_private_data,
232				   file, cmd, arg);
233}
234
235static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
236{
237	struct inode *inode = file_inode(file);
238	struct snd_info_private_data *data;
239	struct snd_info_entry *entry;
240
241	data = file->private_data;
242	if (data == NULL)
243		return 0;
244	entry = data->entry;
245	if (!entry->c.ops->mmap)
246		return -ENXIO;
247	return entry->c.ops->mmap(entry, data->file_private_data,
248				  inode, file, vma);
249}
250
251static int snd_info_entry_open(struct inode *inode, struct file *file)
252{
253	struct snd_info_entry *entry = PDE_DATA(inode);
254	struct snd_info_private_data *data;
 
 
255	int mode, err;
256
257	mutex_lock(&info_mutex);
258	err = alloc_info_private(entry, &data);
259	if (err < 0)
260		goto unlock;
261
 
 
 
 
 
 
262	mode = file->f_flags & O_ACCMODE;
263	if (((mode == O_RDONLY || mode == O_RDWR) && !entry->c.ops->read) ||
264	    ((mode == O_WRONLY || mode == O_RDWR) && !entry->c.ops->write)) {
265		err = -ENODEV;
266		goto error;
 
 
267	}
268
269	if (entry->c.ops->open) {
270		err = entry->c.ops->open(entry, mode, &data->file_private_data);
271		if (err < 0)
272			goto error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
273	}
274
275	file->private_data = data;
276	mutex_unlock(&info_mutex);
 
 
 
 
 
 
 
 
277	return 0;
278
279 error:
 
 
 
 
 
 
 
 
280	kfree(data);
 
 
281	module_put(entry->module);
282 unlock:
283	mutex_unlock(&info_mutex);
284	return err;
285}
286
287static int snd_info_entry_release(struct inode *inode, struct file *file)
288{
289	struct snd_info_private_data *data = file->private_data;
290	struct snd_info_entry *entry = data->entry;
 
291
292	if (entry->c.ops->release)
293		entry->c.ops->release(entry, file->f_flags & O_ACCMODE,
294				      data->file_private_data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
295	module_put(entry->module);
296	kfree(data);
297	return 0;
298}
299
300static const struct file_operations snd_info_entry_operations =
301{
302	.owner =		THIS_MODULE,
303	.llseek =		snd_info_entry_llseek,
304	.read =			snd_info_entry_read,
305	.write =		snd_info_entry_write,
306	.poll =			snd_info_entry_poll,
307	.unlocked_ioctl =	snd_info_entry_ioctl,
308	.mmap =			snd_info_entry_mmap,
309	.open =			snd_info_entry_open,
310	.release =		snd_info_entry_release,
311};
312
313/*
314 * file ops for text proc files
315 */
316static ssize_t snd_info_text_entry_write(struct file *file,
317					 const char __user *buffer,
318					 size_t count, loff_t *offset)
319{
320	struct seq_file *m = file->private_data;
321	struct snd_info_private_data *data = m->private;
322	struct snd_info_entry *entry = data->entry;
323	struct snd_info_buffer *buf;
324	loff_t pos;
325	size_t next;
326	int err = 0;
327
328	if (!entry->c.text.write)
329		return -EIO;
330	pos = *offset;
331	if (!valid_pos(pos, count))
332		return -EIO;
333	next = pos + count;
334	/* don't handle too large text inputs */
335	if (next > 16 * 1024)
336		return -EIO;
337	mutex_lock(&entry->access);
338	buf = data->wbuffer;
339	if (!buf) {
340		data->wbuffer = buf = kzalloc(sizeof(*buf), GFP_KERNEL);
341		if (!buf) {
342			err = -ENOMEM;
343			goto error;
344		}
345	}
346	if (next > buf->len) {
347		char *nbuf = kvzalloc(PAGE_ALIGN(next), GFP_KERNEL);
348		if (!nbuf) {
349			err = -ENOMEM;
350			goto error;
351		}
352		kvfree(buf->buffer);
353		buf->buffer = nbuf;
354		buf->len = PAGE_ALIGN(next);
355	}
356	if (copy_from_user(buf->buffer + pos, buffer, count)) {
357		err = -EFAULT;
358		goto error;
359	}
360	buf->size = next;
361 error:
362	mutex_unlock(&entry->access);
363	if (err < 0)
364		return err;
365	*offset = next;
366	return count;
367}
368
369static int snd_info_seq_show(struct seq_file *seq, void *p)
370{
371	struct snd_info_private_data *data = seq->private;
372	struct snd_info_entry *entry = data->entry;
 
373
374	if (!entry->c.text.read) {
375		return -EIO;
376	} else {
377		data->rbuffer->buffer = (char *)seq; /* XXX hack! */
378		entry->c.text.read(entry, data->rbuffer);
 
 
 
 
 
 
 
 
 
 
 
379	}
380	return 0;
381}
382
383static int snd_info_text_entry_open(struct inode *inode, struct file *file)
 
384{
385	struct snd_info_entry *entry = PDE_DATA(inode);
386	struct snd_info_private_data *data;
387	int err;
388
389	mutex_lock(&info_mutex);
390	err = alloc_info_private(entry, &data);
391	if (err < 0)
392		goto unlock;
393
394	data->rbuffer = kzalloc(sizeof(*data->rbuffer), GFP_KERNEL);
395	if (!data->rbuffer) {
396		err = -ENOMEM;
397		goto error;
 
 
 
 
 
 
 
398	}
399	if (entry->size)
400		err = single_open_size(file, snd_info_seq_show, data,
401				       entry->size);
402	else
403		err = single_open(file, snd_info_seq_show, data);
404	if (err < 0)
405		goto error;
406	mutex_unlock(&info_mutex);
407	return 0;
408
409 error:
410	kfree(data->rbuffer);
411	kfree(data);
412	module_put(entry->module);
413 unlock:
414	mutex_unlock(&info_mutex);
415	return err;
416}
417
418static int snd_info_text_entry_release(struct inode *inode, struct file *file)
419{
420	struct seq_file *m = file->private_data;
421	struct snd_info_private_data *data = m->private;
422	struct snd_info_entry *entry = data->entry;
423
424	if (data->wbuffer && entry->c.text.write)
425		entry->c.text.write(entry, data->wbuffer);
426
427	single_release(inode, file);
428	kfree(data->rbuffer);
429	if (data->wbuffer) {
430		kvfree(data->wbuffer->buffer);
431		kfree(data->wbuffer);
 
 
 
 
 
 
432	}
433
434	module_put(entry->module);
435	kfree(data);
436	return 0;
437}
438
439static const struct file_operations snd_info_text_entry_ops =
440{
441	.owner =		THIS_MODULE,
442	.open =			snd_info_text_entry_open,
443	.release =		snd_info_text_entry_release,
444	.write =		snd_info_text_entry_write,
445	.llseek =		seq_lseek,
446	.read =			seq_read,
 
 
 
447};
448
449static struct snd_info_entry *create_subdir(struct module *mod,
450					    const char *name)
451{
452	struct snd_info_entry *entry;
453
454	entry = snd_info_create_module_entry(mod, name, NULL);
455	if (!entry)
456		return NULL;
457	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
458	if (snd_info_register(entry) < 0) {
459		snd_info_free_entry(entry);
460		return NULL;
461	}
462	return entry;
463}
464
465static struct snd_info_entry *
466snd_info_create_entry(const char *name, struct snd_info_entry *parent);
467
468int __init snd_info_init(void)
469{
470	snd_proc_root = snd_info_create_entry("asound", NULL);
471	if (!snd_proc_root)
 
 
472		return -ENOMEM;
473	snd_proc_root->mode = S_IFDIR | S_IRUGO | S_IXUGO;
474	snd_proc_root->p = proc_mkdir("asound", NULL);
475	if (!snd_proc_root->p)
476		goto error;
477#ifdef CONFIG_SND_OSSEMUL
478	snd_oss_root = create_subdir(THIS_MODULE, "oss");
479	if (!snd_oss_root)
480		goto error;
 
 
 
 
 
 
 
 
481#endif
482#if IS_ENABLED(CONFIG_SND_SEQUENCER)
483	snd_seq_root = create_subdir(THIS_MODULE, "seq");
484	if (!snd_seq_root)
485		goto error;
 
 
 
 
 
 
 
 
486#endif
487	if (snd_info_version_init() < 0 ||
488	    snd_minor_info_init() < 0 ||
489	    snd_minor_info_oss_init() < 0 ||
490	    snd_card_info_init() < 0 ||
491	    snd_info_minor_register() < 0)
492		goto error;
493	return 0;
494
495 error:
496	snd_info_free_entry(snd_proc_root);
497	return -ENOMEM;
498}
499
500int __exit snd_info_done(void)
501{
502	snd_info_free_entry(snd_proc_root);
 
 
 
 
 
 
 
 
 
 
 
 
503	return 0;
504}
505
506/*
 
 
 
 
 
507 * create a card proc file
508 * called from init.c
509 */
510int snd_info_card_create(struct snd_card *card)
511{
512	char str[8];
513	struct snd_info_entry *entry;
514
515	if (snd_BUG_ON(!card))
516		return -ENXIO;
517
518	sprintf(str, "card%i", card->number);
519	entry = create_subdir(card->module, str);
520	if (!entry)
 
 
 
521		return -ENOMEM;
522	card->proc_root = entry;
523	return 0;
524}
525
526/* register all pending info entries */
527static int snd_info_register_recursive(struct snd_info_entry *entry)
528{
529	struct snd_info_entry *p;
530	int err;
531
532	if (!entry->p) {
533		err = snd_info_register(entry);
534		if (err < 0)
535			return err;
536	}
537
538	list_for_each_entry(p, &entry->children, list) {
539		err = snd_info_register_recursive(p);
540		if (err < 0)
541			return err;
542	}
543
544	return 0;
545}
546
547/*
548 * register the card proc file
549 * called from init.c
550 * can be called multiple times for reinitialization
551 */
552int snd_info_card_register(struct snd_card *card)
553{
554	struct proc_dir_entry *p;
555	int err;
556
557	if (snd_BUG_ON(!card))
558		return -ENXIO;
559
560	err = snd_info_register_recursive(card->proc_root);
561	if (err < 0)
562		return err;
563
564	if (!strcmp(card->id, card->proc_root->name))
565		return 0;
566
567	if (card->proc_root_link)
568		return 0;
569	p = proc_symlink(card->id, snd_proc_root->p, card->proc_root->name);
570	if (!p)
571		return -ENOMEM;
572	card->proc_root_link = p;
573	return 0;
574}
575
576/*
577 * called on card->id change
578 */
579void snd_info_card_id_change(struct snd_card *card)
580{
581	mutex_lock(&info_mutex);
582	if (card->proc_root_link) {
583		proc_remove(card->proc_root_link);
584		card->proc_root_link = NULL;
585	}
586	if (strcmp(card->id, card->proc_root->name))
587		card->proc_root_link = proc_symlink(card->id,
588						    snd_proc_root->p,
589						    card->proc_root->name);
590	mutex_unlock(&info_mutex);
591}
592
593/*
594 * de-register the card proc file
595 * called from init.c
596 */
597void snd_info_card_disconnect(struct snd_card *card)
598{
599	if (!card)
600		return;
601	mutex_lock(&info_mutex);
602	proc_remove(card->proc_root_link);
603	card->proc_root_link = NULL;
 
 
604	if (card->proc_root)
605		snd_info_disconnect(card->proc_root);
606	mutex_unlock(&info_mutex);
607}
608
609/*
610 * release the card proc file resources
611 * called from init.c
612 */
613int snd_info_card_free(struct snd_card *card)
614{
615	if (!card)
616		return 0;
617	snd_info_free_entry(card->proc_root);
618	card->proc_root = NULL;
619	return 0;
620}
621
622
623/**
624 * snd_info_get_line - read one line from the procfs buffer
625 * @buffer: the procfs buffer
626 * @line: the buffer to store
627 * @len: the max. buffer size
628 *
629 * Reads one line from the buffer and stores the string.
630 *
631 * Return: Zero if successful, or 1 if error or EOF.
632 */
633int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
634{
635	int c = -1;
636
637	if (snd_BUG_ON(!buffer || !buffer->buffer))
638		return 1;
639	if (len <= 0 || buffer->stop || buffer->error)
640		return 1;
641	while (!buffer->stop) {
642		c = buffer->buffer[buffer->curr++];
643		if (buffer->curr >= buffer->size)
 
 
 
 
 
 
644			buffer->stop = 1;
645		if (c == '\n')
646			break;
647		if (len > 1) {
648			len--;
649			*line++ = c;
650		}
651	}
 
 
 
 
 
652	*line = '\0';
653	return 0;
654}
 
655EXPORT_SYMBOL(snd_info_get_line);
656
657/**
658 * snd_info_get_str - parse a string token
659 * @dest: the buffer to store the string token
660 * @src: the original string
661 * @len: the max. length of token - 1
662 *
663 * Parses the original string and copy a token to the given
664 * string buffer.
665 *
666 * Return: The updated pointer of the original string so that
667 * it can be used for the next call.
668 */
669const char *snd_info_get_str(char *dest, const char *src, int len)
670{
671	int c;
672
673	while (*src == ' ' || *src == '\t')
674		src++;
675	if (*src == '"' || *src == '\'') {
676		c = *src++;
677		while (--len > 0 && *src && *src != c) {
678			*dest++ = *src++;
679		}
680		if (*src == c)
681			src++;
682	} else {
683		while (--len > 0 && *src && *src != ' ' && *src != '\t') {
684			*dest++ = *src++;
685		}
686	}
687	*dest = 0;
688	while (*src == ' ' || *src == '\t')
689		src++;
690	return src;
691}
 
692EXPORT_SYMBOL(snd_info_get_str);
693
694/*
695 * snd_info_create_entry - create an info entry
696 * @name: the proc file name
697 * @parent: the parent directory
698 *
699 * Creates an info entry with the given file name and initializes as
700 * the default state.
701 *
702 * Usually called from other functions such as
703 * snd_info_create_card_entry().
704 *
705 * Return: The pointer of the new instance, or %NULL on failure.
706 */
707static struct snd_info_entry *
708snd_info_create_entry(const char *name, struct snd_info_entry *parent)
709{
710	struct snd_info_entry *entry;
711	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
712	if (entry == NULL)
713		return NULL;
714	entry->name = kstrdup(name, GFP_KERNEL);
715	if (entry->name == NULL) {
716		kfree(entry);
717		return NULL;
718	}
719	entry->mode = S_IFREG | S_IRUGO;
720	entry->content = SNDRV_INFO_CONTENT_TEXT;
721	mutex_init(&entry->access);
722	INIT_LIST_HEAD(&entry->children);
723	INIT_LIST_HEAD(&entry->list);
724	entry->parent = parent;
725	if (parent)
726		list_add_tail(&entry->list, &parent->children);
727	return entry;
728}
729
730/**
731 * snd_info_create_module_entry - create an info entry for the given module
732 * @module: the module pointer
733 * @name: the file name
734 * @parent: the parent directory
735 *
736 * Creates a new info entry and assigns it to the given module.
737 *
738 * Return: The pointer of the new instance, or %NULL on failure.
739 */
740struct snd_info_entry *snd_info_create_module_entry(struct module * module,
741					       const char *name,
742					       struct snd_info_entry *parent)
743{
744	struct snd_info_entry *entry = snd_info_create_entry(name, parent);
745	if (entry)
746		entry->module = module;
 
 
747	return entry;
748}
 
749EXPORT_SYMBOL(snd_info_create_module_entry);
750
751/**
752 * snd_info_create_card_entry - create an info entry for the given card
753 * @card: the card instance
754 * @name: the file name
755 * @parent: the parent directory
756 *
757 * Creates a new info entry and assigns it to the given card.
758 *
759 * Return: The pointer of the new instance, or %NULL on failure.
760 */
761struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
762					     const char *name,
763					     struct snd_info_entry * parent)
764{
765	struct snd_info_entry *entry = snd_info_create_entry(name, parent);
766	if (entry) {
767		entry->module = card->module;
768		entry->card = card;
 
769	}
770	return entry;
771}
 
772EXPORT_SYMBOL(snd_info_create_card_entry);
773
774static void snd_info_disconnect(struct snd_info_entry *entry)
775{
776	struct snd_info_entry *p;
 
777
778	if (!entry->p)
 
 
 
 
779		return;
780	list_for_each_entry(p, &entry->children, list)
781		snd_info_disconnect(p);
782	proc_remove(entry->p);
 
783	entry->p = NULL;
784}
785
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
786/**
787 * snd_info_free_entry - release the info entry
788 * @entry: the info entry
789 *
790 * Releases the info entry.
791 */
792void snd_info_free_entry(struct snd_info_entry * entry)
793{
794	struct snd_info_entry *p, *n;
795
796	if (!entry)
797		return;
798	if (entry->p) {
799		mutex_lock(&info_mutex);
800		snd_info_disconnect(entry);
801		mutex_unlock(&info_mutex);
802	}
803
804	/* free all children at first */
805	list_for_each_entry_safe(p, n, &entry->children, list)
806		snd_info_free_entry(p);
807
808	list_del(&entry->list);
809	kfree(entry->name);
810	if (entry->private_free)
811		entry->private_free(entry);
812	kfree(entry);
813}
 
814EXPORT_SYMBOL(snd_info_free_entry);
815
816/**
817 * snd_info_register - register the info entry
818 * @entry: the info entry
819 *
820 * Registers the proc info entry.
821 *
822 * Return: Zero if successful, or a negative error code on failure.
823 */
824int snd_info_register(struct snd_info_entry * entry)
825{
826	struct proc_dir_entry *root, *p = NULL;
827
828	if (snd_BUG_ON(!entry))
829		return -ENXIO;
830	root = entry->parent == NULL ? snd_proc_root->p : entry->parent->p;
831	mutex_lock(&info_mutex);
832	if (S_ISDIR(entry->mode)) {
833		p = proc_mkdir_mode(entry->name, entry->mode, root);
834		if (!p) {
835			mutex_unlock(&info_mutex);
836			return -ENOMEM;
837		}
838	} else {
839		const struct file_operations *ops;
840		if (entry->content == SNDRV_INFO_CONTENT_DATA)
841			ops = &snd_info_entry_operations;
842		else
843			ops = &snd_info_text_entry_ops;
844		p = proc_create_data(entry->name, entry->mode, root,
845				     ops, entry);
846		if (!p) {
847			mutex_unlock(&info_mutex);
848			return -ENOMEM;
849		}
850		proc_set_size(p, entry->size);
851	}
 
 
 
 
852	entry->p = p;
 
 
853	mutex_unlock(&info_mutex);
854	return 0;
855}
 
856EXPORT_SYMBOL(snd_info_register);
857
858/*
859
860 */
861
 
 
862static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
863{
864	snd_iprintf(buffer,
865		    "Advanced Linux Sound Architecture Driver Version k%s.\n",
866		    init_utsname()->release);
 
867}
868
869static int __init snd_info_version_init(void)
870{
871	struct snd_info_entry *entry;
872
873	entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
874	if (entry == NULL)
875		return -ENOMEM;
876	entry->c.text.read = snd_info_version_read;
877	return snd_info_register(entry); /* freed in error path */
 
 
 
 
 
878}
v3.5.6
   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/slab.h>
  26#include <linux/string.h>
  27#include <linux/module.h>
  28#include <sound/core.h>
  29#include <sound/minors.h>
  30#include <sound/info.h>
  31#include <sound/version.h>
  32#include <linux/proc_fs.h>
  33#include <linux/mutex.h>
  34#include <stdarg.h>
  35
  36/*
  37 *
  38 */
  39
  40#ifdef CONFIG_PROC_FS
  41
  42int snd_info_check_reserved_words(const char *str)
  43{
  44	static char *reserved[] =
  45	{
  46		"version",
  47		"meminfo",
  48		"memdebug",
  49		"detect",
  50		"devices",
  51		"oss",
  52		"cards",
  53		"timers",
  54		"synth",
  55		"pcm",
  56		"seq",
  57		NULL
  58	};
  59	char **xstr = reserved;
  60
  61	while (*xstr) {
  62		if (!strcmp(*xstr, str))
  63			return 0;
  64		xstr++;
  65	}
  66	if (!strncmp(str, "card", 4))
  67		return 0;
  68	return 1;
  69}
  70
  71static DEFINE_MUTEX(info_mutex);
  72
  73struct snd_info_private_data {
  74	struct snd_info_buffer *rbuffer;
  75	struct snd_info_buffer *wbuffer;
  76	struct snd_info_entry *entry;
  77	void *file_private_data;
  78};
  79
  80static int snd_info_version_init(void);
  81static int snd_info_version_done(void);
  82static void snd_info_disconnect(struct snd_info_entry *entry);
  83
  84
  85/* resize the proc r/w buffer */
  86static int resize_info_buffer(struct snd_info_buffer *buffer,
  87			      unsigned int nsize)
  88{
  89	char *nbuf;
  90
  91	nsize = PAGE_ALIGN(nsize);
  92	nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL);
  93	if (! nbuf)
  94		return -ENOMEM;
  95
  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 */
 110int snd_iprintf(struct snd_info_buffer *buffer, const 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		va_list ap;
 123		va_copy(ap, args);
 124		res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
 125		va_end(ap);
 126		if (res < len)
 127			break;
 128		err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
 129		if (err < 0)
 130			break;
 131		len = buffer->len - buffer->size;
 132	}
 133	va_end(args);
 134
 135	if (err < 0)
 136		return err;
 137	buffer->curr += res;
 138	buffer->size += res;
 139	return res;
 140}
 141
 142EXPORT_SYMBOL(snd_iprintf);
 143
 144/*
 145
 146 */
 147
 148static struct proc_dir_entry *snd_proc_root;
 149struct snd_info_entry *snd_seq_root;
 150EXPORT_SYMBOL(snd_seq_root);
 151
 152#ifdef CONFIG_SND_OSSEMUL
 153struct snd_info_entry *snd_oss_root;
 154#endif
 155
 156static void snd_remove_proc_entry(struct proc_dir_entry *parent,
 157				  struct proc_dir_entry *de)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 158{
 159	if (de)
 160		remove_proc_entry(de->name, parent);
 
 
 
 161}
 162
 
 
 
 163static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
 164{
 165	struct snd_info_private_data *data;
 166	struct snd_info_entry *entry;
 167	loff_t ret = -EINVAL, size;
 168
 169	data = file->private_data;
 170	entry = data->entry;
 171	mutex_lock(&entry->access);
 172	if (entry->content == SNDRV_INFO_CONTENT_DATA &&
 173	    entry->c.ops->llseek) {
 174		offset = entry->c.ops->llseek(entry,
 175					      data->file_private_data,
 176					      file, offset, orig);
 177		goto out;
 178	}
 179	if (entry->content == SNDRV_INFO_CONTENT_DATA)
 180		size = entry->size;
 181	else
 182		size = 0;
 183	switch (orig) {
 184	case SEEK_SET:
 185		break;
 186	case SEEK_CUR:
 187		offset += file->f_pos;
 188		break;
 189	case SEEK_END:
 190		if (!size)
 191			goto out;
 192		offset += size;
 193		break;
 194	default:
 195		goto out;
 196	}
 197	if (offset < 0)
 198		goto out;
 199	if (size && offset > size)
 200		offset = size;
 201	file->f_pos = offset;
 202	ret = offset;
 203 out:
 204	mutex_unlock(&entry->access);
 205	return ret;
 206}
 207
 208static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
 209				   size_t count, loff_t * offset)
 210{
 211	struct snd_info_private_data *data;
 212	struct snd_info_entry *entry;
 213	struct snd_info_buffer *buf;
 214	size_t size = 0;
 215	loff_t pos;
 216
 217	data = file->private_data;
 218	if (snd_BUG_ON(!data))
 219		return -ENXIO;
 220	pos = *offset;
 221	if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 222		return -EIO;
 223	if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 224		return -EIO;
 225	entry = data->entry;
 226	switch (entry->content) {
 227	case SNDRV_INFO_CONTENT_TEXT:
 228		buf = data->rbuffer;
 229		if (buf == NULL)
 230			return -EIO;
 231		if (pos >= buf->size)
 232			return 0;
 233		size = buf->size - pos;
 234		size = min(count, size);
 235		if (copy_to_user(buffer, buf->buffer + pos, size))
 236			return -EFAULT;
 237		break;
 238	case SNDRV_INFO_CONTENT_DATA:
 239		if (pos >= entry->size)
 240			return 0;
 241		if (entry->c.ops->read) {
 242			size = entry->size - pos;
 243			size = min(count, size);
 244			size = entry->c.ops->read(entry,
 245						  data->file_private_data,
 246						  file, buffer, size, pos);
 247		}
 248		break;
 249	}
 250	if ((ssize_t) size > 0)
 251		*offset = pos + size;
 252	return size;
 253}
 254
 255static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
 256				    size_t count, loff_t * offset)
 257{
 258	struct snd_info_private_data *data;
 259	struct snd_info_entry *entry;
 260	struct snd_info_buffer *buf;
 261	ssize_t size = 0;
 262	loff_t pos;
 263
 264	data = file->private_data;
 265	if (snd_BUG_ON(!data))
 266		return -ENXIO;
 267	entry = data->entry;
 268	pos = *offset;
 269	if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 270		return -EIO;
 271	if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 272		return -EIO;
 273	switch (entry->content) {
 274	case SNDRV_INFO_CONTENT_TEXT:
 275		buf = data->wbuffer;
 276		if (buf == NULL)
 277			return -EIO;
 278		mutex_lock(&entry->access);
 279		if (pos + count >= buf->len) {
 280			if (resize_info_buffer(buf, pos + count)) {
 281				mutex_unlock(&entry->access);
 282				return -ENOMEM;
 283			}
 284		}
 285		if (copy_from_user(buf->buffer + pos, buffer, count)) {
 286			mutex_unlock(&entry->access);
 287			return -EFAULT;
 288		}
 289		buf->size = pos + count;
 290		mutex_unlock(&entry->access);
 291		size = count;
 292		break;
 293	case SNDRV_INFO_CONTENT_DATA:
 294		if (entry->c.ops->write && count > 0) {
 295			size_t maxsize = entry->size - pos;
 296			count = min(count, maxsize);
 297			size = entry->c.ops->write(entry,
 298						   data->file_private_data,
 299						   file, buffer, count, pos);
 300		}
 301		break;
 302	}
 303	if ((ssize_t) size > 0)
 304		*offset = pos + size;
 305	return size;
 306}
 307
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 308static int snd_info_entry_open(struct inode *inode, struct file *file)
 309{
 310	struct snd_info_entry *entry;
 311	struct snd_info_private_data *data;
 312	struct snd_info_buffer *buffer;
 313	struct proc_dir_entry *p;
 314	int mode, err;
 315
 316	mutex_lock(&info_mutex);
 317	p = PDE(inode);
 318	entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
 319	if (entry == NULL || ! entry->p) {
 320		mutex_unlock(&info_mutex);
 321		return -ENODEV;
 322	}
 323	if (!try_module_get(entry->module)) {
 324		err = -EFAULT;
 325		goto __error1;
 326	}
 327	mode = file->f_flags & O_ACCMODE;
 328	if (mode == O_RDONLY || mode == O_RDWR) {
 329		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
 330		     entry->c.ops->read == NULL)) {
 331		    	err = -ENODEV;
 332		    	goto __error;
 333		}
 334	}
 335	if (mode == O_WRONLY || mode == O_RDWR) {
 336		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
 337		     entry->c.ops->write == NULL)) {
 338		    	err = -ENODEV;
 339		    	goto __error;
 340		}
 341	}
 342	data = kzalloc(sizeof(*data), GFP_KERNEL);
 343	if (data == NULL) {
 344		err = -ENOMEM;
 345		goto __error;
 346	}
 347	data->entry = entry;
 348	switch (entry->content) {
 349	case SNDRV_INFO_CONTENT_TEXT:
 350		if (mode == O_RDONLY || mode == O_RDWR) {
 351			buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 352			if (buffer == NULL)
 353				goto __nomem;
 354			data->rbuffer = buffer;
 355			buffer->len = PAGE_SIZE;
 356			buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
 357			if (buffer->buffer == NULL)
 358				goto __nomem;
 359		}
 360		if (mode == O_WRONLY || mode == O_RDWR) {
 361			buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 362			if (buffer == NULL)
 363				goto __nomem;
 364			data->wbuffer = buffer;
 365			buffer->len = PAGE_SIZE;
 366			buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
 367			if (buffer->buffer == NULL)
 368				goto __nomem;
 369		}
 370		break;
 371	case SNDRV_INFO_CONTENT_DATA:	/* data */
 372		if (entry->c.ops->open) {
 373			if ((err = entry->c.ops->open(entry, mode,
 374						      &data->file_private_data)) < 0) {
 375				kfree(data);
 376				goto __error;
 377			}
 378		}
 379		break;
 380	}
 
 381	file->private_data = data;
 382	mutex_unlock(&info_mutex);
 383	if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
 384	    (mode == O_RDONLY || mode == O_RDWR)) {
 385		if (entry->c.text.read) {
 386			mutex_lock(&entry->access);
 387			entry->c.text.read(entry, data->rbuffer);
 388			mutex_unlock(&entry->access);
 389		}
 390	}
 391	return 0;
 392
 393 __nomem:
 394	if (data->rbuffer) {
 395		kfree(data->rbuffer->buffer);
 396		kfree(data->rbuffer);
 397	}
 398	if (data->wbuffer) {
 399		kfree(data->wbuffer->buffer);
 400		kfree(data->wbuffer);
 401	}
 402	kfree(data);
 403	err = -ENOMEM;
 404      __error:
 405	module_put(entry->module);
 406      __error1:
 407	mutex_unlock(&info_mutex);
 408	return err;
 409}
 410
 411static int snd_info_entry_release(struct inode *inode, struct file *file)
 412{
 413	struct snd_info_entry *entry;
 414	struct snd_info_private_data *data;
 415	int mode;
 416
 417	mode = file->f_flags & O_ACCMODE;
 418	data = file->private_data;
 419	entry = data->entry;
 420	switch (entry->content) {
 421	case SNDRV_INFO_CONTENT_TEXT:
 422		if (data->rbuffer) {
 423			kfree(data->rbuffer->buffer);
 424			kfree(data->rbuffer);
 425		}
 426		if (data->wbuffer) {
 427			if (entry->c.text.write) {
 428				entry->c.text.write(entry, data->wbuffer);
 429				if (data->wbuffer->error) {
 430					snd_printk(KERN_WARNING "data write error to %s (%i)\n",
 431						entry->name,
 432						data->wbuffer->error);
 433				}
 434			}
 435			kfree(data->wbuffer->buffer);
 436			kfree(data->wbuffer);
 437		}
 438		break;
 439	case SNDRV_INFO_CONTENT_DATA:
 440		if (entry->c.ops->release)
 441			entry->c.ops->release(entry, mode,
 442					      data->file_private_data);
 443		break;
 444	}
 445	module_put(entry->module);
 446	kfree(data);
 447	return 0;
 448}
 449
 450static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 451{
 452	struct snd_info_private_data *data;
 453	struct snd_info_entry *entry;
 454	unsigned int mask;
 455
 456	data = file->private_data;
 457	if (data == NULL)
 458		return 0;
 459	entry = data->entry;
 460	mask = 0;
 461	switch (entry->content) {
 462	case SNDRV_INFO_CONTENT_DATA:
 463		if (entry->c.ops->poll)
 464			return entry->c.ops->poll(entry,
 465						  data->file_private_data,
 466						  file, wait);
 467		if (entry->c.ops->read)
 468			mask |= POLLIN | POLLRDNORM;
 469		if (entry->c.ops->write)
 470			mask |= POLLOUT | POLLWRNORM;
 471		break;
 472	}
 473	return mask;
 474}
 475
 476static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
 477				unsigned long arg)
 478{
 
 479	struct snd_info_private_data *data;
 480	struct snd_info_entry *entry;
 
 
 
 
 
 481
 482	data = file->private_data;
 483	if (data == NULL)
 484		return 0;
 485	entry = data->entry;
 486	switch (entry->content) {
 487	case SNDRV_INFO_CONTENT_DATA:
 488		if (entry->c.ops->ioctl)
 489			return entry->c.ops->ioctl(entry,
 490						   data->file_private_data,
 491						   file, cmd, arg);
 492		break;
 493	}
 494	return -ENOTTY;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 495}
 496
 497static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
 498{
 499	struct inode *inode = file->f_path.dentry->d_inode;
 500	struct snd_info_private_data *data;
 501	struct snd_info_entry *entry;
 
 
 
 502
 503	data = file->private_data;
 504	if (data == NULL)
 505		return 0;
 506	entry = data->entry;
 507	switch (entry->content) {
 508	case SNDRV_INFO_CONTENT_DATA:
 509		if (entry->c.ops->mmap)
 510			return entry->c.ops->mmap(entry,
 511						  data->file_private_data,
 512						  inode, file, vma);
 513		break;
 514	}
 515	return -ENXIO;
 
 
 
 516}
 517
 518static const struct file_operations snd_info_entry_operations =
 519{
 520	.owner =		THIS_MODULE,
 521	.llseek =		snd_info_entry_llseek,
 522	.read =			snd_info_entry_read,
 523	.write =		snd_info_entry_write,
 524	.poll =			snd_info_entry_poll,
 525	.unlocked_ioctl =	snd_info_entry_ioctl,
 526	.mmap =			snd_info_entry_mmap,
 527	.open =			snd_info_entry_open,
 528	.release =		snd_info_entry_release,
 529};
 530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 531int __init snd_info_init(void)
 532{
 533	struct proc_dir_entry *p;
 534
 535	p = proc_mkdir("asound", NULL);
 536	if (p == NULL)
 537		return -ENOMEM;
 538	snd_proc_root = p;
 
 
 
 539#ifdef CONFIG_SND_OSSEMUL
 540	{
 541		struct snd_info_entry *entry;
 542		if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", 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_oss_root = entry;
 550	}
 551#endif
 552#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 553	{
 554		struct snd_info_entry *entry;
 555		if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
 556			return -ENOMEM;
 557		entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 558		if (snd_info_register(entry) < 0) {
 559			snd_info_free_entry(entry);
 560			return -ENOMEM;
 561		}
 562		snd_seq_root = entry;
 563	}
 564#endif
 565	snd_info_version_init();
 566	snd_minor_info_init();
 567	snd_minor_info_oss_init();
 568	snd_card_info_init();
 
 
 569	return 0;
 
 
 
 
 570}
 571
 572int __exit snd_info_done(void)
 573{
 574	snd_card_info_done();
 575	snd_minor_info_oss_done();
 576	snd_minor_info_done();
 577	snd_info_version_done();
 578	if (snd_proc_root) {
 579#if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 580		snd_info_free_entry(snd_seq_root);
 581#endif
 582#ifdef CONFIG_SND_OSSEMUL
 583		snd_info_free_entry(snd_oss_root);
 584#endif
 585		snd_remove_proc_entry(NULL, snd_proc_root);
 586	}
 587	return 0;
 588}
 589
 590/*
 591
 592 */
 593
 594
 595/*
 596 * create a card proc file
 597 * called from init.c
 598 */
 599int snd_info_card_create(struct snd_card *card)
 600{
 601	char str[8];
 602	struct snd_info_entry *entry;
 603
 604	if (snd_BUG_ON(!card))
 605		return -ENXIO;
 606
 607	sprintf(str, "card%i", card->number);
 608	if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
 609		return -ENOMEM;
 610	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 611	if (snd_info_register(entry) < 0) {
 612		snd_info_free_entry(entry);
 613		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 614	}
 615	card->proc_root = entry;
 616	return 0;
 617}
 618
 619/*
 620 * register the card proc file
 621 * called from init.c
 
 622 */
 623int snd_info_card_register(struct snd_card *card)
 624{
 625	struct proc_dir_entry *p;
 
 626
 627	if (snd_BUG_ON(!card))
 628		return -ENXIO;
 629
 
 
 
 
 630	if (!strcmp(card->id, card->proc_root->name))
 631		return 0;
 632
 633	p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
 634	if (p == NULL)
 
 
 635		return -ENOMEM;
 636	card->proc_root_link = p;
 637	return 0;
 638}
 639
 640/*
 641 * called on card->id change
 642 */
 643void snd_info_card_id_change(struct snd_card *card)
 644{
 645	mutex_lock(&info_mutex);
 646	if (card->proc_root_link) {
 647		snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
 648		card->proc_root_link = NULL;
 649	}
 650	if (strcmp(card->id, card->proc_root->name))
 651		card->proc_root_link = proc_symlink(card->id,
 652						    snd_proc_root,
 653						    card->proc_root->name);
 654	mutex_unlock(&info_mutex);
 655}
 656
 657/*
 658 * de-register the card proc file
 659 * called from init.c
 660 */
 661void snd_info_card_disconnect(struct snd_card *card)
 662{
 663	if (!card)
 664		return;
 665	mutex_lock(&info_mutex);
 666	if (card->proc_root_link) {
 667		snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
 668		card->proc_root_link = NULL;
 669	}
 670	if (card->proc_root)
 671		snd_info_disconnect(card->proc_root);
 672	mutex_unlock(&info_mutex);
 673}
 674
 675/*
 676 * release the card proc file resources
 677 * called from init.c
 678 */
 679int snd_info_card_free(struct snd_card *card)
 680{
 681	if (!card)
 682		return 0;
 683	snd_info_free_entry(card->proc_root);
 684	card->proc_root = NULL;
 685	return 0;
 686}
 687
 688
 689/**
 690 * snd_info_get_line - read one line from the procfs buffer
 691 * @buffer: the procfs buffer
 692 * @line: the buffer to store
 693 * @len: the max. buffer size - 1
 694 *
 695 * Reads one line from the buffer and stores the string.
 696 *
 697 * Returns zero if successful, or 1 if error or EOF.
 698 */
 699int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
 700{
 701	int c = -1;
 702
 
 
 703	if (len <= 0 || buffer->stop || buffer->error)
 704		return 1;
 705	while (--len > 0) {
 706		c = buffer->buffer[buffer->curr++];
 707		if (c == '\n') {
 708			if (buffer->curr >= buffer->size)
 709				buffer->stop = 1;
 710			break;
 711		}
 712		*line++ = c;
 713		if (buffer->curr >= buffer->size) {
 714			buffer->stop = 1;
 
 715			break;
 
 
 
 716		}
 717	}
 718	while (c != '\n' && !buffer->stop) {
 719		c = buffer->buffer[buffer->curr++];
 720		if (buffer->curr >= buffer->size)
 721			buffer->stop = 1;
 722	}
 723	*line = '\0';
 724	return 0;
 725}
 726
 727EXPORT_SYMBOL(snd_info_get_line);
 728
 729/**
 730 * snd_info_get_str - parse a string token
 731 * @dest: the buffer to store the string token
 732 * @src: the original string
 733 * @len: the max. length of token - 1
 734 *
 735 * Parses the original string and copy a token to the given
 736 * string buffer.
 737 *
 738 * Returns the updated pointer of the original string so that
 739 * it can be used for the next call.
 740 */
 741const char *snd_info_get_str(char *dest, const char *src, int len)
 742{
 743	int c;
 744
 745	while (*src == ' ' || *src == '\t')
 746		src++;
 747	if (*src == '"' || *src == '\'') {
 748		c = *src++;
 749		while (--len > 0 && *src && *src != c) {
 750			*dest++ = *src++;
 751		}
 752		if (*src == c)
 753			src++;
 754	} else {
 755		while (--len > 0 && *src && *src != ' ' && *src != '\t') {
 756			*dest++ = *src++;
 757		}
 758	}
 759	*dest = 0;
 760	while (*src == ' ' || *src == '\t')
 761		src++;
 762	return src;
 763}
 764
 765EXPORT_SYMBOL(snd_info_get_str);
 766
 767/**
 768 * snd_info_create_entry - create an info entry
 769 * @name: the proc file name
 
 770 *
 771 * Creates an info entry with the given file name and initializes as
 772 * the default state.
 773 *
 774 * Usually called from other functions such as
 775 * snd_info_create_card_entry().
 776 *
 777 * Returns the pointer of the new instance, or NULL on failure.
 778 */
 779static struct snd_info_entry *snd_info_create_entry(const char *name)
 
 780{
 781	struct snd_info_entry *entry;
 782	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 783	if (entry == NULL)
 784		return NULL;
 785	entry->name = kstrdup(name, GFP_KERNEL);
 786	if (entry->name == NULL) {
 787		kfree(entry);
 788		return NULL;
 789	}
 790	entry->mode = S_IFREG | S_IRUGO;
 791	entry->content = SNDRV_INFO_CONTENT_TEXT;
 792	mutex_init(&entry->access);
 793	INIT_LIST_HEAD(&entry->children);
 794	INIT_LIST_HEAD(&entry->list);
 
 
 
 795	return entry;
 796}
 797
 798/**
 799 * snd_info_create_module_entry - create an info entry for the given module
 800 * @module: the module pointer
 801 * @name: the file name
 802 * @parent: the parent directory
 803 *
 804 * Creates a new info entry and assigns it to the given module.
 805 *
 806 * Returns the pointer of the new instance, or NULL on failure.
 807 */
 808struct snd_info_entry *snd_info_create_module_entry(struct module * module,
 809					       const char *name,
 810					       struct snd_info_entry *parent)
 811{
 812	struct snd_info_entry *entry = snd_info_create_entry(name);
 813	if (entry) {
 814		entry->module = module;
 815		entry->parent = parent;
 816	}
 817	return entry;
 818}
 819
 820EXPORT_SYMBOL(snd_info_create_module_entry);
 821
 822/**
 823 * snd_info_create_card_entry - create an info entry for the given card
 824 * @card: the card instance
 825 * @name: the file name
 826 * @parent: the parent directory
 827 *
 828 * Creates a new info entry and assigns it to the given card.
 829 *
 830 * Returns the pointer of the new instance, or NULL on failure.
 831 */
 832struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
 833					     const char *name,
 834					     struct snd_info_entry * parent)
 835{
 836	struct snd_info_entry *entry = snd_info_create_entry(name);
 837	if (entry) {
 838		entry->module = card->module;
 839		entry->card = card;
 840		entry->parent = parent;
 841	}
 842	return entry;
 843}
 844
 845EXPORT_SYMBOL(snd_info_create_card_entry);
 846
 847static void snd_info_disconnect(struct snd_info_entry *entry)
 848{
 849	struct list_head *p, *n;
 850	struct proc_dir_entry *root;
 851
 852	list_for_each_safe(p, n, &entry->children) {
 853		snd_info_disconnect(list_entry(p, struct snd_info_entry, list));
 854	}
 855
 856	if (! entry->p)
 857		return;
 858	list_del_init(&entry->list);
 859	root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 860	snd_BUG_ON(!root);
 861	snd_remove_proc_entry(root, entry->p);
 862	entry->p = NULL;
 863}
 864
 865static int snd_info_dev_free_entry(struct snd_device *device)
 866{
 867	struct snd_info_entry *entry = device->device_data;
 868	snd_info_free_entry(entry);
 869	return 0;
 870}
 871
 872static int snd_info_dev_register_entry(struct snd_device *device)
 873{
 874	struct snd_info_entry *entry = device->device_data;
 875	return snd_info_register(entry);
 876}
 877
 878/**
 879 * snd_card_proc_new - create an info entry for the given card
 880 * @card: the card instance
 881 * @name: the file name
 882 * @entryp: the pointer to store the new info entry
 883 *
 884 * Creates a new info entry and assigns it to the given card.
 885 * Unlike snd_info_create_card_entry(), this function registers the
 886 * info entry as an ALSA device component, so that it can be
 887 * unregistered/released without explicit call.
 888 * Also, you don't have to register this entry via snd_info_register(),
 889 * since this will be registered by snd_card_register() automatically.
 890 *
 891 * The parent is assumed as card->proc_root.
 892 *
 893 * For releasing this entry, use snd_device_free() instead of
 894 * snd_info_free_entry(). 
 895 *
 896 * Returns zero if successful, or a negative error code on failure.
 897 */
 898int snd_card_proc_new(struct snd_card *card, const char *name,
 899		      struct snd_info_entry **entryp)
 900{
 901	static struct snd_device_ops ops = {
 902		.dev_free = snd_info_dev_free_entry,
 903		.dev_register =	snd_info_dev_register_entry,
 904		/* disconnect is done via snd_info_card_disconnect() */
 905	};
 906	struct snd_info_entry *entry;
 907	int err;
 908
 909	entry = snd_info_create_card_entry(card, name, card->proc_root);
 910	if (! entry)
 911		return -ENOMEM;
 912	if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
 913		snd_info_free_entry(entry);
 914		return err;
 915	}
 916	if (entryp)
 917		*entryp = entry;
 918	return 0;
 919}
 920
 921EXPORT_SYMBOL(snd_card_proc_new);
 922
 923/**
 924 * snd_info_free_entry - release the info entry
 925 * @entry: the info entry
 926 *
 927 * Releases the info entry.  Don't call this after registered.
 928 */
 929void snd_info_free_entry(struct snd_info_entry * entry)
 930{
 931	if (entry == NULL)
 
 
 932		return;
 933	if (entry->p) {
 934		mutex_lock(&info_mutex);
 935		snd_info_disconnect(entry);
 936		mutex_unlock(&info_mutex);
 937	}
 
 
 
 
 
 
 938	kfree(entry->name);
 939	if (entry->private_free)
 940		entry->private_free(entry);
 941	kfree(entry);
 942}
 943
 944EXPORT_SYMBOL(snd_info_free_entry);
 945
 946/**
 947 * snd_info_register - register the info entry
 948 * @entry: the info entry
 949 *
 950 * Registers the proc info entry.
 951 *
 952 * Returns zero if successful, or a negative error code on failure.
 953 */
 954int snd_info_register(struct snd_info_entry * entry)
 955{
 956	struct proc_dir_entry *root, *p = NULL;
 957
 958	if (snd_BUG_ON(!entry))
 959		return -ENXIO;
 960	root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 961	mutex_lock(&info_mutex);
 962	p = create_proc_entry(entry->name, entry->mode, root);
 963	if (!p) {
 964		mutex_unlock(&info_mutex);
 965		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 966	}
 967	if (!S_ISDIR(entry->mode))
 968		p->proc_fops = &snd_info_entry_operations;
 969	p->size = entry->size;
 970	p->data = entry;
 971	entry->p = p;
 972	if (entry->parent)
 973		list_add_tail(&entry->list, &entry->parent->children);
 974	mutex_unlock(&info_mutex);
 975	return 0;
 976}
 977
 978EXPORT_SYMBOL(snd_info_register);
 979
 980/*
 981
 982 */
 983
 984static struct snd_info_entry *snd_info_version_entry;
 985
 986static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
 987{
 988	snd_iprintf(buffer,
 989		    "Advanced Linux Sound Architecture Driver Version "
 990		    CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
 991		   );
 992}
 993
 994static int __init snd_info_version_init(void)
 995{
 996	struct snd_info_entry *entry;
 997
 998	entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
 999	if (entry == NULL)
1000		return -ENOMEM;
1001	entry->c.text.read = snd_info_version_read;
1002	if (snd_info_register(entry) < 0) {
1003		snd_info_free_entry(entry);
1004		return -ENOMEM;
1005	}
1006	snd_info_version_entry = entry;
1007	return 0;
1008}
1009
1010static int __exit snd_info_version_done(void)
1011{
1012	snd_info_free_entry(snd_info_version_entry);
1013	return 0;
1014}
1015
1016#endif /* CONFIG_PROC_FS */