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