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