SAFE public projects git trees. - safe/jmp/linux-2.6/blob - sound/core/info.c

   1 /*
   2  *  Information interface for ALSA driver
   3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   4  *
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #include <sound/driver.h>
  23 #include <linux/init.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/time.h>
  26 #include <linux/smp_lock.h>
  27 #include <linux/string.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/devfs_fs_kernel.h>
  34 #include <linux/mutex.h>
  35 #include <stdarg.h>
  36
  37 /*
  38  *
  39  */
  40
  41 #ifdef CONFIG_PROC_FS
  42
  43 int snd_info_check_reserved_words(const char *str)
  44 {
  45         static char *reserved[] =
  46         {
  47                 "version",
  48                 "meminfo",
  49                 "memdebug",
  50                 "detect",
  51                 "devices",
  52                 "oss",
  53                 "cards",
  54                 "timers",
  55                 "synth",
  56                 "pcm",
  57                 "seq",
  58                 NULL
  59         };
  60         char **xstr = reserved;
  61
  62         while (*xstr) {
  63                 if (!strcmp(*xstr, str))
  64                         return 0;
  65                 xstr++;
  66         }
  67         if (!strncmp(str, "card", 4))
  68                 return 0;
  69         return 1;
  70 }
  71
  72 static DEFINE_MUTEX(info_mutex);
  73
  74 struct snd_info_private_data {
  75         struct snd_info_buffer *rbuffer;
  76         struct snd_info_buffer *wbuffer;
  77         struct snd_info_entry *entry;
  78         void *file_private_data;
  79 };
  80
  81 static int snd_info_version_init(void);
  82 static int snd_info_version_done(void);
  83
  84
  85 /**
  86  * snd_iprintf - printf on the procfs buffer
  87  * @buffer: the procfs buffer
  88  * @fmt: the printf format
  89  *
  90  * Outputs the string on the procfs buffer just like printf().
  91  *
  92  * Returns the size of output string.
  93  */
  94 int snd_iprintf(struct snd_info_buffer *buffer, char *fmt,...)
  95 {
  96         va_list args;
  97         int len, res;
  98
  99         if (buffer->stop || buffer->error)
 100                 return 0;
 101         len = buffer->len - buffer->size;
 102         va_start(args, fmt);
 103         res = vsnprintf(buffer->curr, len, fmt, args);
 104         va_end(args);
 105         if (res >= len) {
 106                 buffer->stop = 1;
 107                 return 0;
 108         }
 109         buffer->curr += res;
 110         buffer->size += res;
 111         return res;
 112 }
 113
 114 EXPORT_SYMBOL(snd_iprintf);
 115
 116 /*
 117
 118  */
 119
 120 static struct proc_dir_entry *snd_proc_root = NULL;
 121 struct snd_info_entry *snd_seq_root = NULL;
 122 EXPORT_SYMBOL(snd_seq_root);
 123
 124 #ifdef CONFIG_SND_OSSEMUL
 125 struct snd_info_entry *snd_oss_root = NULL;
 126 #endif
 127
 128 static inline void snd_info_entry_prepare(struct proc_dir_entry *de)
 129 {
 130         de->owner = THIS_MODULE;
 131 }
 132
 133 static void snd_remove_proc_entry(struct proc_dir_entry *parent,
 134                                   struct proc_dir_entry *de)
 135 {
 136         if (de)
 137                 remove_proc_entry(de->name, parent);
 138 }
 139
 140 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
 141 {
 142         struct snd_info_private_data *data;
 143         struct snd_info_entry *entry;
 144         loff_t ret;
 145
 146         data = file->private_data;
 147         entry = data->entry;
 148         lock_kernel();
 149         switch (entry->content) {
 150         case SNDRV_INFO_CONTENT_TEXT:
 151                 switch (orig) {
 152                 case 0: /* SEEK_SET */
 153                         file->f_pos = offset;
 154                         ret = file->f_pos;
 155                         goto out;
 156                 case 1: /* SEEK_CUR */
 157                         file->f_pos += offset;
 158                         ret = file->f_pos;
 159                         goto out;
 160                 case 2: /* SEEK_END */
 161                 default:
 162                         ret = -EINVAL;
 163                         goto out;
 164                 }
 165                 break;
 166         case SNDRV_INFO_CONTENT_DATA:
 167                 if (entry->c.ops->llseek) {
 168                         ret = entry->c.ops->llseek(entry,
 169                                                     data->file_private_data,
 170                                                     file, offset, orig);
 171                         goto out;
 172                 }
 173                 break;
 174         }
 175         ret = -ENXIO;
 176 out:
 177         unlock_kernel();
 178         return ret;
 179 }
 180
 181 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
 182                                    size_t count, loff_t * offset)
 183 {
 184         struct snd_info_private_data *data;
 185         struct snd_info_entry *entry;
 186         struct snd_info_buffer *buf;
 187         size_t size = 0;
 188         loff_t pos;
 189
 190         data = file->private_data;
 191         snd_assert(data != NULL, return -ENXIO);
 192         pos = *offset;
 193         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 194                 return -EIO;
 195         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 196                 return -EIO;
 197         entry = data->entry;
 198         switch (entry->content) {
 199         case SNDRV_INFO_CONTENT_TEXT:
 200                 buf = data->rbuffer;
 201                 if (buf == NULL)
 202                         return -EIO;
 203                 if (pos >= buf->size)
 204                         return 0;
 205                 size = buf->size - pos;
 206                 size = min(count, size);
 207                 if (copy_to_user(buffer, buf->buffer + pos, size))
 208                         return -EFAULT;
 209                 break;
 210         case SNDRV_INFO_CONTENT_DATA:
 211                 if (entry->c.ops->read)
 212                         size = entry->c.ops->read(entry,
 213                                                   data->file_private_data,
 214                                                   file, buffer, count, pos);
 215                 break;
 216         }
 217         if ((ssize_t) size > 0)
 218                 *offset = pos + size;
 219         return size;
 220 }
 221
 222 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
 223                                     size_t count, loff_t * offset)
 224 {
 225         struct snd_info_private_data *data;
 226         struct snd_info_entry *entry;
 227         struct snd_info_buffer *buf;
 228         size_t size = 0;
 229         loff_t pos;
 230
 231         data = file->private_data;
 232         snd_assert(data != NULL, return -ENXIO);
 233         entry = data->entry;
 234         pos = *offset;
 235         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 236                 return -EIO;
 237         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 238                 return -EIO;
 239         switch (entry->content) {
 240         case SNDRV_INFO_CONTENT_TEXT:
 241                 buf = data->wbuffer;
 242                 if (buf == NULL)
 243                         return -EIO;
 244                 if (pos >= buf->len)
 245                         return -ENOMEM;
 246                 size = buf->len - pos;
 247                 size = min(count, size);
 248                 if (copy_from_user(buf->buffer + pos, buffer, size))
 249                         return -EFAULT;
 250                 if ((long)buf->size < pos + size)
 251                         buf->size = pos + size;
 252                 break;
 253         case SNDRV_INFO_CONTENT_DATA:
 254                 if (entry->c.ops->write)
 255                         size = entry->c.ops->write(entry,
 256                                                    data->file_private_data,
 257                                                    file, buffer, count, pos);
 258                 break;
 259         }
 260         if ((ssize_t) size > 0)
 261                 *offset = pos + size;
 262         return size;
 263 }
 264
 265 static int snd_info_entry_open(struct inode *inode, struct file *file)
 266 {
 267         struct snd_info_entry *entry;
 268         struct snd_info_private_data *data;
 269         struct snd_info_buffer *buffer;
 270         struct proc_dir_entry *p;
 271         int mode, err;
 272
 273         mutex_lock(&info_mutex);
 274         p = PDE(inode);
 275         entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
 276         if (entry == NULL || entry->disconnected) {
 277                 mutex_unlock(&info_mutex);
 278                 return -ENODEV;
 279         }
 280         if (!try_module_get(entry->module)) {
 281                 err = -EFAULT;
 282                 goto __error1;
 283         }
 284         mode = file->f_flags & O_ACCMODE;
 285         if (mode == O_RDONLY || mode == O_RDWR) {
 286                 if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
 287                      !entry->c.text.read_size) ||
 288                     (entry->content == SNDRV_INFO_CONTENT_DATA &&
 289                      entry->c.ops->read == NULL)) {
 290                         err = -ENODEV;
 291                         goto __error;
 292                 }
 293         }
 294         if (mode == O_WRONLY || mode == O_RDWR) {
 295                 if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
 296                      !entry->c.text.write_size) ||
 297                     (entry->content == SNDRV_INFO_CONTENT_DATA &&
 298                      entry->c.ops->write == NULL)) {
 299                         err = -ENODEV;
 300                         goto __error;
 301                 }
 302         }
 303         data = kzalloc(sizeof(*data), GFP_KERNEL);
 304         if (data == NULL) {
 305                 err = -ENOMEM;
 306                 goto __error;
 307         }
 308         data->entry = entry;
 309         switch (entry->content) {
 310         case SNDRV_INFO_CONTENT_TEXT:
 311                 if (mode == O_RDONLY || mode == O_RDWR) {
 312                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 313                         if (buffer == NULL) {
 314                                 kfree(data);
 315                                 err = -ENOMEM;
 316                                 goto __error;
 317                         }
 318                         buffer->len = (entry->c.text.read_size +
 319                                       (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
 320                         buffer->buffer = vmalloc(buffer->len);
 321                         if (buffer->buffer == NULL) {
 322                                 kfree(buffer);
 323                                 kfree(data);
 324                                 err = -ENOMEM;
 325                                 goto __error;
 326                         }
 327                         buffer->curr = buffer->buffer;
 328                         data->rbuffer = buffer;
 329                 }
 330                 if (mode == O_WRONLY || mode == O_RDWR) {
 331                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 332                         if (buffer == NULL) {
 333                                 if (mode == O_RDWR) {
 334                                         vfree(data->rbuffer->buffer);
 335                                         kfree(data->rbuffer);
 336                                 }
 337                                 kfree(data);
 338                                 err = -ENOMEM;
 339                                 goto __error;
 340                         }
 341                         buffer->len = (entry->c.text.write_size +
 342                                       (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
 343                         buffer->buffer = vmalloc(buffer->len);
 344                         if (buffer->buffer == NULL) {
 345                                 if (mode == O_RDWR) {
 346                                         vfree(data->rbuffer->buffer);
 347                                         kfree(data->rbuffer);
 348                                 }
 349                                 kfree(buffer);
 350                                 kfree(data);
 351                                 err = -ENOMEM;
 352                                 goto __error;
 353                         }
 354                         buffer->curr = buffer->buffer;
 355                         data->wbuffer = buffer;
 356                 }
 357                 break;
 358         case SNDRV_INFO_CONTENT_DATA:   /* data */
 359                 if (entry->c.ops->open) {
 360                         if ((err = entry->c.ops->open(entry, mode,
 361                                                       &data->file_private_data)) < 0) {
 362                                 kfree(data);
 363                                 goto __error;
 364                         }
 365                 }
 366                 break;
 367         }
 368         file->private_data = data;
 369         mutex_unlock(&info_mutex);
 370         if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
 371             (mode == O_RDONLY || mode == O_RDWR)) {
 372                 if (entry->c.text.read) {
 373                         mutex_lock(&entry->access);
 374                         entry->c.text.read(entry, data->rbuffer);
 375                         mutex_unlock(&entry->access);
 376                 }
 377         }
 378         return 0;
 379
 380       __error:
 381         module_put(entry->module);
 382       __error1:
 383         mutex_unlock(&info_mutex);
 384         return err;
 385 }
 386
 387 static int snd_info_entry_release(struct inode *inode, struct file *file)
 388 {
 389         struct snd_info_entry *entry;
 390         struct snd_info_private_data *data;
 391         int mode;
 392
 393         mode = file->f_flags & O_ACCMODE;
 394         data = file->private_data;
 395         entry = data->entry;
 396         switch (entry->content) {
 397         case SNDRV_INFO_CONTENT_TEXT:
 398                 if (mode == O_RDONLY || mode == O_RDWR) {
 399                         vfree(data->rbuffer->buffer);
 400                         kfree(data->rbuffer);
 401                 }
 402                 if (mode == O_WRONLY || mode == O_RDWR) {
 403                         if (entry->c.text.write) {
 404                                 entry->c.text.write(entry, data->wbuffer);
 405                                 if (data->wbuffer->error) {
 406                                         snd_printk(KERN_WARNING "data write error to %s (%i)\n",
 407                                                 entry->name,
 408                                                 data->wbuffer->error);
 409                                 }
 410                         }
 411                         vfree(data->wbuffer->buffer);
 412                         kfree(data->wbuffer);
 413                 }
 414                 break;
 415         case SNDRV_INFO_CONTENT_DATA:
 416                 if (entry->c.ops->release)
 417                         entry->c.ops->release(entry, mode,
 418                                               data->file_private_data);
 419                 break;
 420         }
 421         module_put(entry->module);
 422         kfree(data);
 423         return 0;
 424 }
 425
 426 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
 427 {
 428         struct snd_info_private_data *data;
 429         struct snd_info_entry *entry;
 430         unsigned int mask;
 431
 432         data = file->private_data;
 433         if (data == NULL)
 434                 return 0;
 435         entry = data->entry;
 436         mask = 0;
 437         switch (entry->content) {
 438         case SNDRV_INFO_CONTENT_DATA:
 439                 if (entry->c.ops->poll)
 440                         return entry->c.ops->poll(entry,
 441                                                   data->file_private_data,
 442                                                   file, wait);
 443                 if (entry->c.ops->read)
 444                         mask |= POLLIN | POLLRDNORM;
 445                 if (entry->c.ops->write)
 446                         mask |= POLLOUT | POLLWRNORM;
 447                 break;
 448         }
 449         return mask;
 450 }
 451
 452 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
 453                                 unsigned long arg)
 454 {
 455         struct snd_info_private_data *data;
 456         struct snd_info_entry *entry;
 457
 458         data = file->private_data;
 459         if (data == NULL)
 460                 return 0;
 461         entry = data->entry;
 462         switch (entry->content) {
 463         case SNDRV_INFO_CONTENT_DATA:
 464                 if (entry->c.ops->ioctl)
 465                         return entry->c.ops->ioctl(entry,
 466                                                    data->file_private_data,
 467                                                    file, cmd, arg);
 468                 break;
 469         }
 470         return -ENOTTY;
 471 }
 472
 473 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
 474 {
 475         struct inode *inode = file->f_dentry->d_inode;
 476         struct snd_info_private_data *data;
 477         struct snd_info_entry *entry;
 478
 479         data = file->private_data;
 480         if (data == NULL)
 481                 return 0;
 482         entry = data->entry;
 483         switch (entry->content) {
 484         case SNDRV_INFO_CONTENT_DATA:
 485                 if (entry->c.ops->mmap)
 486                         return entry->c.ops->mmap(entry,
 487                                                   data->file_private_data,
 488                                                   inode, file, vma);
 489                 break;
 490         }
 491         return -ENXIO;
 492 }
 493
 494 static struct file_operations snd_info_entry_operations =
 495 {
 496         .owner =                THIS_MODULE,
 497         .llseek =               snd_info_entry_llseek,
 498         .read =                 snd_info_entry_read,
 499         .write =                snd_info_entry_write,
 500         .poll =                 snd_info_entry_poll,
 501         .unlocked_ioctl =       snd_info_entry_ioctl,
 502         .mmap =                 snd_info_entry_mmap,
 503         .open =                 snd_info_entry_open,
 504         .release =              snd_info_entry_release,
 505 };
 506
 507 /**
 508  * snd_create_proc_entry - create a procfs entry
 509  * @name: the name of the proc file
 510  * @mode: the file permission bits, S_Ixxx
 511  * @parent: the parent proc-directory entry
 512  *
 513  * Creates a new proc file entry with the given name and permission
 514  * on the given directory.
 515  *
 516  * Returns the pointer of new instance or NULL on failure.
 517  */
 518 static struct proc_dir_entry *snd_create_proc_entry(const char *name, mode_t mode,
 519                                                     struct proc_dir_entry *parent)
 520 {
 521         struct proc_dir_entry *p;
 522         p = create_proc_entry(name, mode, parent);
 523         if (p)
 524                 snd_info_entry_prepare(p);
 525         return p;
 526 }
 527
 528 int __init snd_info_init(void)
 529 {
 530         struct proc_dir_entry *p;
 531
 532         p = snd_create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, &proc_root);
 533         if (p == NULL)
 534                 return -ENOMEM;
 535         snd_proc_root = p;
 536 #ifdef CONFIG_SND_OSSEMUL
 537         {
 538                 struct snd_info_entry *entry;
 539                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
 540                         return -ENOMEM;
 541                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 542                 if (snd_info_register(entry) < 0) {
 543                         snd_info_free_entry(entry);
 544                         return -ENOMEM;
 545                 }
 546                 snd_oss_root = entry;
 547         }
 548 #endif
 549 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 550         {
 551                 struct snd_info_entry *entry;
 552                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
 553                         return -ENOMEM;
 554                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 555                 if (snd_info_register(entry) < 0) {
 556                         snd_info_free_entry(entry);
 557                         return -ENOMEM;
 558                 }
 559                 snd_seq_root = entry;
 560         }
 561 #endif
 562         snd_info_version_init();
 563         snd_minor_info_init();
 564         snd_minor_info_oss_init();
 565         snd_card_info_init();
 566         return 0;
 567 }
 568
 569 int __exit snd_info_done(void)
 570 {
 571         snd_card_info_done();
 572         snd_minor_info_oss_done();
 573         snd_minor_info_done();
 574         snd_info_version_done();
 575         if (snd_proc_root) {
 576 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 577                 snd_info_unregister(snd_seq_root);
 578 #endif
 579 #ifdef CONFIG_SND_OSSEMUL
 580                 snd_info_unregister(snd_oss_root);
 581 #endif
 582                 snd_remove_proc_entry(&proc_root, snd_proc_root);
 583         }
 584         return 0;
 585 }
 586
 587 /*
 588
 589  */
 590
 591
 592 /*
 593  * create a card proc file
 594  * called from init.c
 595  */
 596 int snd_info_card_create(struct snd_card *card)
 597 {
 598         char str[8];
 599         struct snd_info_entry *entry;
 600
 601         snd_assert(card != NULL, 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  */
 619 int snd_info_card_register(struct snd_card *card)
 620 {
 621         struct proc_dir_entry *p;
 622
 623         snd_assert(card != NULL, return -ENXIO);
 624
 625         if (!strcmp(card->id, card->proc_root->name))
 626                 return 0;
 627
 628         p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
 629         if (p == NULL)
 630                 return -ENOMEM;
 631         card->proc_root_link = p;
 632         return 0;
 633 }
 634
 635 /*
 636  * de-register the card proc file
 637  * called from init.c
 638  */
 639 int snd_info_card_free(struct snd_card *card)
 640 {
 641         snd_assert(card != NULL, return -ENXIO);
 642         if (card->proc_root_link) {
 643                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
 644                 card->proc_root_link = NULL;
 645         }
 646         if (card->proc_root) {
 647                 snd_info_unregister(card->proc_root);
 648                 card->proc_root = NULL;
 649         }
 650         return 0;
 651 }
 652
 653
 654 /**
 655  * snd_info_get_line - read one line from the procfs buffer
 656  * @buffer: the procfs buffer
 657  * @line: the buffer to store
 658  * @len: the max. buffer size - 1
 659  *
 660  * Reads one line from the buffer and stores the string.
 661  *
 662  * Returns zero if successful, or 1 if error or EOF.
 663  */
 664 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
 665 {
 666         int c = -1;
 667
 668         if (len <= 0 || buffer->stop || buffer->error)
 669                 return 1;
 670         while (--len > 0) {
 671                 c = *buffer->curr++;
 672                 if (c == '\n') {
 673                         if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 674                                 buffer->stop = 1;
 675                         }
 676                         break;
 677                 }
 678                 *line++ = c;
 679                 if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 680                         buffer->stop = 1;
 681                         break;
 682                 }
 683         }
 684         while (c != '\n' && !buffer->stop) {
 685                 c = *buffer->curr++;
 686                 if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 687                         buffer->stop = 1;
 688                 }
 689         }
 690         *line = '\0';
 691         return 0;
 692 }
 693
 694 EXPORT_SYMBOL(snd_info_get_line);
 695
 696 /**
 697  * snd_info_get_str - parse a string token
 698  * @dest: the buffer to store the string token
 699  * @src: the original string
 700  * @len: the max. length of token - 1
 701  *
 702  * Parses the original string and copy a token to the given
 703  * string buffer.
 704  *
 705  * Returns the updated pointer of the original string so that
 706  * it can be used for the next call.
 707  */
 708 char *snd_info_get_str(char *dest, char *src, int len)
 709 {
 710         int c;
 711
 712         while (*src == ' ' || *src == '\t')
 713                 src++;
 714         if (*src == '"' || *src == '\'') {
 715                 c = *src++;
 716                 while (--len > 0 && *src && *src != c) {
 717                         *dest++ = *src++;
 718                 }
 719                 if (*src == c)
 720                         src++;
 721         } else {
 722                 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
 723                         *dest++ = *src++;
 724                 }
 725         }
 726         *dest = 0;
 727         while (*src == ' ' || *src == '\t')
 728                 src++;
 729         return src;
 730 }
 731
 732 EXPORT_SYMBOL(snd_info_get_str);
 733
 734 /**
 735  * snd_info_create_entry - create an info entry
 736  * @name: the proc file name
 737  *
 738  * Creates an info entry with the given file name and initializes as
 739  * the default state.
 740  *
 741  * Usually called from other functions such as
 742  * snd_info_create_card_entry().
 743  *
 744  * Returns the pointer of the new instance, or NULL on failure.
 745  */
 746 static struct snd_info_entry *snd_info_create_entry(const char *name)
 747 {
 748         struct snd_info_entry *entry;
 749         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 750         if (entry == NULL)
 751                 return NULL;
 752         entry->name = kstrdup(name, GFP_KERNEL);
 753         if (entry->name == NULL) {
 754                 kfree(entry);
 755                 return NULL;
 756         }
 757         entry->mode = S_IFREG | S_IRUGO;
 758         entry->content = SNDRV_INFO_CONTENT_TEXT;
 759         mutex_init(&entry->access);
 760         return entry;
 761 }
 762
 763 /**
 764  * snd_info_create_module_entry - create an info entry for the given module
 765  * @module: the module pointer
 766  * @name: the file name
 767  * @parent: the parent directory
 768  *
 769  * Creates a new info entry and assigns it to the given module.
 770  *
 771  * Returns the pointer of the new instance, or NULL on failure.
 772  */
 773 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
 774                                                const char *name,
 775                                                struct snd_info_entry *parent)
 776 {
 777         struct snd_info_entry *entry = snd_info_create_entry(name);
 778         if (entry) {
 779                 entry->module = module;
 780                 entry->parent = parent;
 781         }
 782         return entry;
 783 }
 784
 785 EXPORT_SYMBOL(snd_info_create_module_entry);
 786
 787 /**
 788  * snd_info_create_card_entry - create an info entry for the given card
 789  * @card: the card instance
 790  * @name: the file name
 791  * @parent: the parent directory
 792  *
 793  * Creates a new info entry and assigns it to the given card.
 794  *
 795  * Returns the pointer of the new instance, or NULL on failure.
 796  */
 797 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
 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 = card->module;
 804                 entry->card = card;
 805                 entry->parent = parent;
 806         }
 807         return entry;
 808 }
 809
 810 EXPORT_SYMBOL(snd_info_create_card_entry);
 811
 812 static int snd_info_dev_free_entry(struct snd_device *device)
 813 {
 814         struct snd_info_entry *entry = device->device_data;
 815         snd_info_free_entry(entry);
 816         return 0;
 817 }
 818
 819 static int snd_info_dev_register_entry(struct snd_device *device)
 820 {
 821         struct snd_info_entry *entry = device->device_data;
 822         return snd_info_register(entry);
 823 }
 824
 825 static int snd_info_dev_disconnect_entry(struct snd_device *device)
 826 {
 827         struct snd_info_entry *entry = device->device_data;
 828         entry->disconnected = 1;
 829         return 0;
 830 }
 831
 832 static int snd_info_dev_unregister_entry(struct snd_device *device)
 833 {
 834         struct snd_info_entry *entry = device->device_data;
 835         return snd_info_unregister(entry);
 836 }
 837
 838 /**
 839  * snd_card_proc_new - create an info entry for the given card
 840  * @card: the card instance
 841  * @name: the file name
 842  * @entryp: the pointer to store the new info entry
 843  *
 844  * Creates a new info entry and assigns it to the given card.
 845  * Unlike snd_info_create_card_entry(), this function registers the
 846  * info entry as an ALSA device component, so that it can be
 847  * unregistered/released without explicit call.
 848  * Also, you don't have to register this entry via snd_info_register(),
 849  * since this will be registered by snd_card_register() automatically.
 850  *
 851  * The parent is assumed as card->proc_root.
 852  *
 853  * For releasing this entry, use snd_device_free() instead of
 854  * snd_info_free_entry().
 855  *
 856  * Returns zero if successful, or a negative error code on failure.
 857  */
 858 int snd_card_proc_new(struct snd_card *card, const char *name,
 859                       struct snd_info_entry **entryp)
 860 {
 861         static struct snd_device_ops ops = {
 862                 .dev_free = snd_info_dev_free_entry,
 863                 .dev_register = snd_info_dev_register_entry,
 864                 .dev_disconnect = snd_info_dev_disconnect_entry,
 865                 .dev_unregister = snd_info_dev_unregister_entry
 866         };
 867         struct snd_info_entry *entry;
 868         int err;
 869
 870         entry = snd_info_create_card_entry(card, name, card->proc_root);
 871         if (! entry)
 872                 return -ENOMEM;
 873         if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
 874                 snd_info_free_entry(entry);
 875                 return err;
 876         }
 877         if (entryp)
 878                 *entryp = entry;
 879         return 0;
 880 }
 881
 882 EXPORT_SYMBOL(snd_card_proc_new);
 883
 884 /**
 885  * snd_info_free_entry - release the info entry
 886  * @entry: the info entry
 887  *
 888  * Releases the info entry.  Don't call this after registered.
 889  */
 890 void snd_info_free_entry(struct snd_info_entry * entry)
 891 {
 892         if (entry == NULL)
 893                 return;
 894         kfree(entry->name);
 895         if (entry->private_free)
 896                 entry->private_free(entry);
 897         kfree(entry);
 898 }
 899
 900 EXPORT_SYMBOL(snd_info_free_entry);
 901
 902 /**
 903  * snd_info_register - register the info entry
 904  * @entry: the info entry
 905  *
 906  * Registers the proc info entry.
 907  *
 908  * Returns zero if successful, or a negative error code on failure.
 909  */
 910 int snd_info_register(struct snd_info_entry * entry)
 911 {
 912         struct proc_dir_entry *root, *p = NULL;
 913
 914         snd_assert(entry != NULL, return -ENXIO);
 915         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 916         mutex_lock(&info_mutex);
 917         p = snd_create_proc_entry(entry->name, entry->mode, root);
 918         if (!p) {
 919                 mutex_unlock(&info_mutex);
 920                 return -ENOMEM;
 921         }
 922         p->owner = entry->module;
 923         if (!S_ISDIR(entry->mode))
 924                 p->proc_fops = &snd_info_entry_operations;
 925         p->size = entry->size;
 926         p->data = entry;
 927         entry->p = p;
 928         mutex_unlock(&info_mutex);
 929         return 0;
 930 }
 931
 932 EXPORT_SYMBOL(snd_info_register);
 933
 934 /**
 935  * snd_info_unregister - de-register the info entry
 936  * @entry: the info entry
 937  *
 938  * De-registers the info entry and releases the instance.
 939  *
 940  * Returns zero if successful, or a negative error code on failure.
 941  */
 942 int snd_info_unregister(struct snd_info_entry * entry)
 943 {
 944         struct proc_dir_entry *root;
 945
 946         if (! entry)
 947                 return 0;
 948         snd_assert(entry->p != NULL, return -ENXIO);
 949         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 950         snd_assert(root, return -ENXIO);
 951         mutex_lock(&info_mutex);
 952         snd_remove_proc_entry(root, entry->p);
 953         mutex_unlock(&info_mutex);
 954         snd_info_free_entry(entry);
 955         return 0;
 956 }
 957
 958 EXPORT_SYMBOL(snd_info_unregister);
 959
 960 /*
 961
 962  */
 963
 964 static struct snd_info_entry *snd_info_version_entry = NULL;
 965
 966 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
 967 {
 968         snd_iprintf(buffer,
 969                     "Advanced Linux Sound Architecture Driver Version "
 970                     CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
 971                    );
 972 }
 973
 974 static int __init snd_info_version_init(void)
 975 {
 976         struct snd_info_entry *entry;
 977
 978         entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
 979         if (entry == NULL)
 980                 return -ENOMEM;
 981         entry->c.text.read_size = 256;
 982         entry->c.text.read = snd_info_version_read;
 983         if (snd_info_register(entry) < 0) {
 984                 snd_info_free_entry(entry);
 985                 return -ENOMEM;
 986         }
 987         snd_info_version_entry = entry;
 988         return 0;
 989 }
 990
 991 static int __exit snd_info_version_done(void)
 992 {
 993         if (snd_info_version_entry)
 994                 snd_info_unregister(snd_info_version_entry);
 995         return 0;
 996 }
 997
 998 #endif /* CONFIG_PROC_FS */