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v3.15
   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
  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 | __GFP_ZERO);
  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 * Return: The size of output string, or a negative error code.
 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 loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
 157{
 158	struct snd_info_private_data *data;
 159	struct snd_info_entry *entry;
 160	loff_t ret = -EINVAL, size;
 161
 162	data = file->private_data;
 163	entry = data->entry;
 164	mutex_lock(&entry->access);
 165	if (entry->content == SNDRV_INFO_CONTENT_DATA &&
 166	    entry->c.ops->llseek) {
 167		offset = entry->c.ops->llseek(entry,
 168					      data->file_private_data,
 169					      file, offset, orig);
 170		goto out;
 171	}
 172	if (entry->content == SNDRV_INFO_CONTENT_DATA)
 173		size = entry->size;
 174	else
 175		size = 0;
 176	switch (orig) {
 177	case SEEK_SET:
 178		break;
 179	case SEEK_CUR:
 180		offset += file->f_pos;
 181		break;
 182	case SEEK_END:
 183		if (!size)
 184			goto out;
 185		offset += size;
 186		break;
 187	default:
 188		goto out;
 189	}
 190	if (offset < 0)
 191		goto out;
 192	if (size && offset > size)
 193		offset = size;
 194	file->f_pos = offset;
 195	ret = offset;
 196 out:
 197	mutex_unlock(&entry->access);
 198	return ret;
 199}
 200
 201static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
 202				   size_t count, loff_t * offset)
 203{
 204	struct snd_info_private_data *data;
 205	struct snd_info_entry *entry;
 206	struct snd_info_buffer *buf;
 207	size_t size = 0;
 208	loff_t pos;
 209
 210	data = file->private_data;
 211	if (snd_BUG_ON(!data))
 212		return -ENXIO;
 213	pos = *offset;
 214	if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 215		return -EIO;
 216	if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 217		return -EIO;
 218	entry = data->entry;
 219	switch (entry->content) {
 220	case SNDRV_INFO_CONTENT_TEXT:
 221		buf = data->rbuffer;
 222		if (buf == NULL)
 223			return -EIO;
 224		if (pos >= buf->size)
 225			return 0;
 226		size = buf->size - pos;
 227		size = min(count, size);
 228		if (copy_to_user(buffer, buf->buffer + pos, size))
 229			return -EFAULT;
 230		break;
 231	case SNDRV_INFO_CONTENT_DATA:
 232		if (pos >= entry->size)
 233			return 0;
 234		if (entry->c.ops->read) {
 235			size = entry->size - pos;
 236			size = min(count, size);
 237			size = entry->c.ops->read(entry,
 238						  data->file_private_data,
 239						  file, buffer, size, pos);
 240		}
 241		break;
 242	}
 243	if ((ssize_t) size > 0)
 244		*offset = pos + size;
 245	return size;
 246}
 247
 248static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
 249				    size_t count, loff_t * offset)
 250{
 251	struct snd_info_private_data *data;
 252	struct snd_info_entry *entry;
 253	struct snd_info_buffer *buf;
 254	ssize_t size = 0;
 255	loff_t pos;
 256
 257	data = file->private_data;
 258	if (snd_BUG_ON(!data))
 259		return -ENXIO;
 260	entry = data->entry;
 261	pos = *offset;
 262	if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 263		return -EIO;
 264	if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 265		return -EIO;
 266	switch (entry->content) {
 267	case SNDRV_INFO_CONTENT_TEXT:
 268		buf = data->wbuffer;
 269		if (buf == NULL)
 270			return -EIO;
 271		mutex_lock(&entry->access);
 272		if (pos + count >= buf->len) {
 273			if (resize_info_buffer(buf, pos + count)) {
 274				mutex_unlock(&entry->access);
 275				return -ENOMEM;
 276			}
 277		}
 278		if (copy_from_user(buf->buffer + pos, buffer, count)) {
 279			mutex_unlock(&entry->access);
 280			return -EFAULT;
 281		}
 282		buf->size = pos + count;
 283		mutex_unlock(&entry->access);
 284		size = count;
 285		break;
 286	case SNDRV_INFO_CONTENT_DATA:
 287		if (entry->c.ops->write && count > 0) {
 288			size_t maxsize = entry->size - pos;
 289			count = min(count, maxsize);
 290			size = entry->c.ops->write(entry,
 291						   data->file_private_data,
 292						   file, buffer, count, pos);
 293		}
 294		break;
 295	}
 296	if ((ssize_t) size > 0)
 297		*offset = pos + size;
 298	return size;
 299}
 300
 301static int snd_info_entry_open(struct inode *inode, struct file *file)
 302{
 303	struct snd_info_entry *entry;
 304	struct snd_info_private_data *data;
 305	struct snd_info_buffer *buffer;
 
 306	int mode, err;
 307
 308	mutex_lock(&info_mutex);
 309	entry = PDE_DATA(inode);
 
 310	if (entry == NULL || ! entry->p) {
 311		mutex_unlock(&info_mutex);
 312		return -ENODEV;
 313	}
 314	if (!try_module_get(entry->module)) {
 315		err = -EFAULT;
 316		goto __error1;
 317	}
 318	mode = file->f_flags & O_ACCMODE;
 319	if (mode == O_RDONLY || mode == O_RDWR) {
 320		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
 321		     entry->c.ops->read == NULL)) {
 322		    	err = -ENODEV;
 323		    	goto __error;
 324		}
 325	}
 326	if (mode == O_WRONLY || mode == O_RDWR) {
 327		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
 328		     entry->c.ops->write == NULL)) {
 329		    	err = -ENODEV;
 330		    	goto __error;
 331		}
 332	}
 333	data = kzalloc(sizeof(*data), GFP_KERNEL);
 334	if (data == NULL) {
 335		err = -ENOMEM;
 336		goto __error;
 337	}
 338	data->entry = entry;
 339	switch (entry->content) {
 340	case SNDRV_INFO_CONTENT_TEXT:
 341		if (mode == O_RDONLY || mode == O_RDWR) {
 342			buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 343			if (buffer == NULL)
 344				goto __nomem;
 345			data->rbuffer = buffer;
 346			buffer->len = PAGE_SIZE;
 347			buffer->buffer = kzalloc(buffer->len, GFP_KERNEL);
 348			if (buffer->buffer == NULL)
 349				goto __nomem;
 350		}
 351		if (mode == O_WRONLY || mode == O_RDWR) {
 352			buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 353			if (buffer == NULL)
 354				goto __nomem;
 355			data->wbuffer = buffer;
 356			buffer->len = PAGE_SIZE;
 357			buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
 358			if (buffer->buffer == NULL)
 359				goto __nomem;
 360		}
 361		break;
 362	case SNDRV_INFO_CONTENT_DATA:	/* data */
 363		if (entry->c.ops->open) {
 364			if ((err = entry->c.ops->open(entry, mode,
 365						      &data->file_private_data)) < 0) {
 366				kfree(data);
 367				goto __error;
 368			}
 369		}
 370		break;
 371	}
 372	file->private_data = data;
 373	mutex_unlock(&info_mutex);
 374	if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
 375	    (mode == O_RDONLY || mode == O_RDWR)) {
 376		if (entry->c.text.read) {
 377			mutex_lock(&entry->access);
 378			entry->c.text.read(entry, data->rbuffer);
 379			mutex_unlock(&entry->access);
 380		}
 381	}
 382	return 0;
 383
 384 __nomem:
 385	if (data->rbuffer) {
 386		kfree(data->rbuffer->buffer);
 387		kfree(data->rbuffer);
 388	}
 389	if (data->wbuffer) {
 390		kfree(data->wbuffer->buffer);
 391		kfree(data->wbuffer);
 392	}
 393	kfree(data);
 394	err = -ENOMEM;
 395      __error:
 396	module_put(entry->module);
 397      __error1:
 398	mutex_unlock(&info_mutex);
 399	return err;
 400}
 401
 402static int snd_info_entry_release(struct inode *inode, struct file *file)
 403{
 404	struct snd_info_entry *entry;
 405	struct snd_info_private_data *data;
 406	int mode;
 407
 408	mode = file->f_flags & O_ACCMODE;
 409	data = file->private_data;
 410	entry = data->entry;
 411	switch (entry->content) {
 412	case SNDRV_INFO_CONTENT_TEXT:
 413		if (data->rbuffer) {
 414			kfree(data->rbuffer->buffer);
 415			kfree(data->rbuffer);
 416		}
 417		if (data->wbuffer) {
 418			if (entry->c.text.write) {
 419				entry->c.text.write(entry, data->wbuffer);
 420				if (data->wbuffer->error) {
 421					if (entry->card)
 422						dev_warn(entry->card->dev, "info: data write error to %s (%i)\n",
 423							 entry->name,
 424							 data->wbuffer->error);
 425					else
 426						pr_warn("ALSA: info: data write error to %s (%i)\n",
 427							entry->name,
 428							data->wbuffer->error);
 429				}
 430			}
 431			kfree(data->wbuffer->buffer);
 432			kfree(data->wbuffer);
 433		}
 434		break;
 435	case SNDRV_INFO_CONTENT_DATA:
 436		if (entry->c.ops->release)
 437			entry->c.ops->release(entry, mode,
 438					      data->file_private_data);
 439		break;
 440	}
 441	module_put(entry->module);
 442	kfree(data);
 443	return 0;
 444}
 445
 446static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
 447{
 448	struct snd_info_private_data *data;
 449	struct snd_info_entry *entry;
 450	unsigned int mask;
 451
 452	data = file->private_data;
 453	if (data == NULL)
 454		return 0;
 455	entry = data->entry;
 456	mask = 0;
 457	switch (entry->content) {
 458	case SNDRV_INFO_CONTENT_DATA:
 459		if (entry->c.ops->poll)
 460			return entry->c.ops->poll(entry,
 461						  data->file_private_data,
 462						  file, wait);
 463		if (entry->c.ops->read)
 464			mask |= POLLIN | POLLRDNORM;
 465		if (entry->c.ops->write)
 466			mask |= POLLOUT | POLLWRNORM;
 467		break;
 468	}
 469	return mask;
 470}
 471
 472static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
 473				unsigned long arg)
 474{
 475	struct snd_info_private_data *data;
 476	struct snd_info_entry *entry;
 477
 478	data = file->private_data;
 479	if (data == NULL)
 480		return 0;
 481	entry = data->entry;
 482	switch (entry->content) {
 483	case SNDRV_INFO_CONTENT_DATA:
 484		if (entry->c.ops->ioctl)
 485			return entry->c.ops->ioctl(entry,
 486						   data->file_private_data,
 487						   file, cmd, arg);
 488		break;
 489	}
 490	return -ENOTTY;
 491}
 492
 493static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
 494{
 495	struct inode *inode = file_inode(file);
 496	struct snd_info_private_data *data;
 497	struct snd_info_entry *entry;
 498
 499	data = file->private_data;
 500	if (data == NULL)
 501		return 0;
 502	entry = data->entry;
 503	switch (entry->content) {
 504	case SNDRV_INFO_CONTENT_DATA:
 505		if (entry->c.ops->mmap)
 506			return entry->c.ops->mmap(entry,
 507						  data->file_private_data,
 508						  inode, file, vma);
 509		break;
 510	}
 511	return -ENXIO;
 512}
 513
 514static const struct file_operations snd_info_entry_operations =
 515{
 516	.owner =		THIS_MODULE,
 517	.llseek =		snd_info_entry_llseek,
 518	.read =			snd_info_entry_read,
 519	.write =		snd_info_entry_write,
 520	.poll =			snd_info_entry_poll,
 521	.unlocked_ioctl =	snd_info_entry_ioctl,
 522	.mmap =			snd_info_entry_mmap,
 523	.open =			snd_info_entry_open,
 524	.release =		snd_info_entry_release,
 525};
 526
 527int __init snd_info_init(void)
 528{
 529	struct proc_dir_entry *p;
 530
 531	p = proc_mkdir("asound", NULL);
 532	if (p == NULL)
 533		return -ENOMEM;
 534	snd_proc_root = p;
 535#ifdef CONFIG_SND_OSSEMUL
 536	{
 537		struct snd_info_entry *entry;
 538		if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
 539			return -ENOMEM;
 540		entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 541		if (snd_info_register(entry) < 0) {
 542			snd_info_free_entry(entry);
 543			return -ENOMEM;
 544		}
 545		snd_oss_root = entry;
 546	}
 547#endif
 548#if IS_ENABLED(CONFIG_SND_SEQUENCER)
 549	{
 550		struct snd_info_entry *entry;
 551		if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", 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_seq_root = entry;
 559	}
 560#endif
 561	snd_info_version_init();
 562	snd_minor_info_init();
 563	snd_minor_info_oss_init();
 564	snd_card_info_init();
 565	return 0;
 566}
 567
 568int __exit snd_info_done(void)
 569{
 570	snd_card_info_done();
 571	snd_minor_info_oss_done();
 572	snd_minor_info_done();
 573	snd_info_version_done();
 574	if (snd_proc_root) {
 575#if IS_ENABLED(CONFIG_SND_SEQUENCER)
 576		snd_info_free_entry(snd_seq_root);
 577#endif
 578#ifdef CONFIG_SND_OSSEMUL
 579		snd_info_free_entry(snd_oss_root);
 580#endif
 581		proc_remove(snd_proc_root);
 582	}
 583	return 0;
 584}
 585
 586/*
 587
 588 */
 589
 590
 591/*
 592 * create a card proc file
 593 * called from init.c
 594 */
 595int snd_info_card_create(struct snd_card *card)
 596{
 597	char str[8];
 598	struct snd_info_entry *entry;
 599
 600	if (snd_BUG_ON(!card))
 601		return -ENXIO;
 602
 603	sprintf(str, "card%i", card->number);
 604	if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
 605		return -ENOMEM;
 606	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 607	if (snd_info_register(entry) < 0) {
 608		snd_info_free_entry(entry);
 609		return -ENOMEM;
 610	}
 611	card->proc_root = entry;
 612	return 0;
 613}
 614
 615/*
 616 * register the card proc file
 617 * called from init.c
 618 */
 619int snd_info_card_register(struct snd_card *card)
 620{
 621	struct proc_dir_entry *p;
 622
 623	if (snd_BUG_ON(!card))
 624		return -ENXIO;
 625
 626	if (!strcmp(card->id, card->proc_root->name))
 627		return 0;
 628
 629	p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
 630	if (p == NULL)
 631		return -ENOMEM;
 632	card->proc_root_link = p;
 633	return 0;
 634}
 635
 636/*
 637 * called on card->id change
 638 */
 639void snd_info_card_id_change(struct snd_card *card)
 640{
 641	mutex_lock(&info_mutex);
 642	if (card->proc_root_link) {
 643		proc_remove(card->proc_root_link);
 644		card->proc_root_link = NULL;
 645	}
 646	if (strcmp(card->id, card->proc_root->name))
 647		card->proc_root_link = proc_symlink(card->id,
 648						    snd_proc_root,
 649						    card->proc_root->name);
 650	mutex_unlock(&info_mutex);
 651}
 652
 653/*
 654 * de-register the card proc file
 655 * called from init.c
 656 */
 657void snd_info_card_disconnect(struct snd_card *card)
 658{
 659	if (!card)
 660		return;
 661	mutex_lock(&info_mutex);
 662	proc_remove(card->proc_root_link);
 663	card->proc_root_link = NULL;
 
 
 664	if (card->proc_root)
 665		snd_info_disconnect(card->proc_root);
 666	mutex_unlock(&info_mutex);
 667}
 668
 669/*
 670 * release the card proc file resources
 671 * called from init.c
 672 */
 673int snd_info_card_free(struct snd_card *card)
 674{
 675	if (!card)
 676		return 0;
 677	snd_info_free_entry(card->proc_root);
 678	card->proc_root = NULL;
 679	return 0;
 680}
 681
 682
 683/**
 684 * snd_info_get_line - read one line from the procfs buffer
 685 * @buffer: the procfs buffer
 686 * @line: the buffer to store
 687 * @len: the max. buffer size - 1
 688 *
 689 * Reads one line from the buffer and stores the string.
 690 *
 691 * Return: Zero if successful, or 1 if error or EOF.
 692 */
 693int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
 694{
 695	int c = -1;
 696
 697	if (snd_BUG_ON(!buffer || !buffer->buffer))
 698		return 1;
 699	if (len <= 0 || buffer->stop || buffer->error)
 700		return 1;
 701	while (!buffer->stop) {
 702		c = buffer->buffer[buffer->curr++];
 703		if (buffer->curr >= buffer->size)
 
 
 
 
 
 
 704			buffer->stop = 1;
 705		if (c == '\n')
 706			break;
 707		if (len) {
 708			len--;
 709			*line++ = c;
 710		}
 711	}
 
 
 
 
 
 712	*line = '\0';
 713	return 0;
 714}
 715
 716EXPORT_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 * Return: The updated pointer of the original string so that
 728 * it can be used for the next call.
 729 */
 730const char *snd_info_get_str(char *dest, const 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
 754EXPORT_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 * Return: The pointer of the new instance, or %NULL on failure.
 767 */
 768static 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 * Return: The pointer of the new instance, or %NULL on failure.
 796 */
 797struct 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
 809EXPORT_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 * Return: The pointer of the new instance, or %NULL on failure.
 820 */
 821struct 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
 834EXPORT_SYMBOL(snd_info_create_card_entry);
 835
 836static 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	proc_remove(entry->p);
 851	entry->p = NULL;
 852}
 853
 854static 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
 861static 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 * Return: Zero if successful, or a negative error code on failure.
 886 */
 887int 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
 910EXPORT_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 */
 918void 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
 933EXPORT_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 * Return: Zero if successful, or a negative error code on failure.
 942 */
 943int 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	if (S_ISDIR(entry->mode)) {
 952		p = proc_mkdir_mode(entry->name, entry->mode, root);
 953		if (!p) {
 954			mutex_unlock(&info_mutex);
 955			return -ENOMEM;
 956		}
 957	} else {
 958		p = proc_create_data(entry->name, entry->mode, root,
 959					&snd_info_entry_operations, entry);
 960		if (!p) {
 961			mutex_unlock(&info_mutex);
 962			return -ENOMEM;
 963		}
 964		proc_set_size(p, entry->size);
 965	}
 
 
 
 
 966	entry->p = p;
 967	if (entry->parent)
 968		list_add_tail(&entry->list, &entry->parent->children);
 969	mutex_unlock(&info_mutex);
 970	return 0;
 971}
 972
 973EXPORT_SYMBOL(snd_info_register);
 974
 975/*
 976
 977 */
 978
 979static struct snd_info_entry *snd_info_version_entry;
 980
 981static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
 982{
 983	snd_iprintf(buffer,
 984		    "Advanced Linux Sound Architecture Driver Version k%s.\n",
 985		    init_utsname()->release);
 
 986}
 987
 988static int __init snd_info_version_init(void)
 989{
 990	struct snd_info_entry *entry;
 991
 992	entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
 993	if (entry == NULL)
 994		return -ENOMEM;
 995	entry->c.text.read = snd_info_version_read;
 996	if (snd_info_register(entry) < 0) {
 997		snd_info_free_entry(entry);
 998		return -ENOMEM;
 999	}
1000	snd_info_version_entry = entry;
1001	return 0;
1002}
1003
1004static int __exit snd_info_version_done(void)
1005{
1006	snd_info_free_entry(snd_info_version_entry);
1007	return 0;
1008}
1009
1010#endif /* CONFIG_PROC_FS */
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 */