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 <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 DECLARE_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
  83
  84 /**
  85  * snd_iprintf - printf on the procfs buffer
  86  * @buffer: the procfs buffer
  87  * @fmt: the printf format
  88  *
  89  * Outputs the string on the procfs buffer just like printf().
  90  *
  91  * Returns the size of output string.
  92  */
  93 int snd_iprintf(struct snd_info_buffer *buffer, char *fmt,...)
  94 {
  95         va_list args;
  96         int len, res;
  97
  98         if (buffer->stop || buffer->error)
  99                 return 0;
 100         len = buffer->len - buffer->size;
 101         va_start(args, fmt);
 102         res = vsnprintf(buffer->curr, len, fmt, args);
 103         va_end(args);
 104         if (res >= len) {
 105                 buffer->stop = 1;
 106                 return 0;
 107         }
 108         buffer->curr += res;
 109         buffer->size += res;
 110         return res;
 111 }
 112
 113 /*
 114
 115  */
 116
 117 static struct proc_dir_entry *snd_proc_root = NULL;
 118 struct snd_info_entry *snd_seq_root = NULL;
 119 #ifdef CONFIG_SND_OSSEMUL
 120 struct snd_info_entry *snd_oss_root = NULL;
 121 #endif
 122
 123 static inline void snd_info_entry_prepare(struct proc_dir_entry *de)
 124 {
 125         de->owner = THIS_MODULE;
 126 }
 127
 128 static void snd_remove_proc_entry(struct proc_dir_entry *parent,
 129                                   struct proc_dir_entry *de)
 130 {
 131         if (de)
 132                 remove_proc_entry(de->name, parent);
 133 }
 134
 135 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
 136 {
 137         struct snd_info_private_data *data;
 138         struct snd_info_entry *entry;
 139         loff_t ret;
 140
 141         data = file->private_data;
 142         entry = data->entry;
 143         lock_kernel();
 144         switch (entry->content) {
 145         case SNDRV_INFO_CONTENT_TEXT:
 146                 switch (orig) {
 147                 case 0: /* SEEK_SET */
 148                         file->f_pos = offset;
 149                         ret = file->f_pos;
 150                         goto out;
 151                 case 1: /* SEEK_CUR */
 152                         file->f_pos += offset;
 153                         ret = file->f_pos;
 154                         goto out;
 155                 case 2: /* SEEK_END */
 156                 default:
 157                         ret = -EINVAL;
 158                         goto out;
 159                 }
 160                 break;
 161         case SNDRV_INFO_CONTENT_DATA:
 162                 if (entry->c.ops->llseek) {
 163                         ret = entry->c.ops->llseek(entry,
 164                                                     data->file_private_data,
 165                                                     file, offset, orig);
 166                         goto out;
 167                 }
 168                 break;
 169         }
 170         ret = -ENXIO;
 171 out:
 172         unlock_kernel();
 173         return ret;
 174 }
 175
 176 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
 177                                    size_t count, loff_t * offset)
 178 {
 179         struct snd_info_private_data *data;
 180         struct snd_info_entry *entry;
 181         struct snd_info_buffer *buf;
 182         size_t size = 0;
 183         loff_t pos;
 184
 185         data = file->private_data;
 186         snd_assert(data != NULL, return -ENXIO);
 187         pos = *offset;
 188         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 189                 return -EIO;
 190         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 191                 return -EIO;
 192         entry = data->entry;
 193         switch (entry->content) {
 194         case SNDRV_INFO_CONTENT_TEXT:
 195                 buf = data->rbuffer;
 196                 if (buf == NULL)
 197                         return -EIO;
 198                 if (pos >= buf->size)
 199                         return 0;
 200                 size = buf->size - pos;
 201                 size = min(count, size);
 202                 if (copy_to_user(buffer, buf->buffer + pos, size))
 203                         return -EFAULT;
 204                 break;
 205         case SNDRV_INFO_CONTENT_DATA:
 206                 if (entry->c.ops->read)
 207                         size = entry->c.ops->read(entry,
 208                                                   data->file_private_data,
 209                                                   file, buffer, count, pos);
 210                 break;
 211         }
 212         if ((ssize_t) size > 0)
 213                 *offset = pos + size;
 214         return size;
 215 }
 216
 217 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer,
 218                                     size_t count, loff_t * offset)
 219 {
 220         struct snd_info_private_data *data;
 221         struct snd_info_entry *entry;
 222         struct snd_info_buffer *buf;
 223         size_t size = 0;
 224         loff_t pos;
 225
 226         data = file->private_data;
 227         snd_assert(data != NULL, return -ENXIO);
 228         entry = data->entry;
 229         pos = *offset;
 230         if (pos < 0 || (long) pos != pos || (ssize_t) count < 0)
 231                 return -EIO;
 232         if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos)
 233                 return -EIO;
 234         switch (entry->content) {
 235         case SNDRV_INFO_CONTENT_TEXT:
 236                 buf = data->wbuffer;
 237                 if (buf == NULL)
 238                         return -EIO;
 239                 if (pos >= buf->len)
 240                         return -ENOMEM;
 241                 size = buf->len - pos;
 242                 size = min(count, size);
 243                 if (copy_from_user(buf->buffer + pos, buffer, size))
 244                         return -EFAULT;
 245                 if ((long)buf->size < pos + size)
 246                         buf->size = pos + size;
 247                 break;
 248         case SNDRV_INFO_CONTENT_DATA:
 249                 if (entry->c.ops->write)
 250                         size = entry->c.ops->write(entry,
 251                                                    data->file_private_data,
 252                                                    file, buffer, count, pos);
 253                 break;
 254         }
 255         if ((ssize_t) size > 0)
 256                 *offset = pos + size;
 257         return size;
 258 }
 259
 260 static int snd_info_entry_open(struct inode *inode, struct file *file)
 261 {
 262         struct snd_info_entry *entry;
 263         struct snd_info_private_data *data;
 264         struct snd_info_buffer *buffer;
 265         struct proc_dir_entry *p;
 266         int mode, err;
 267
 268         down(&info_mutex);
 269         p = PDE(inode);
 270         entry = p == NULL ? NULL : (struct snd_info_entry *)p->data;
 271         if (entry == NULL || entry->disconnected) {
 272                 up(&info_mutex);
 273                 return -ENODEV;
 274         }
 275         if (!try_module_get(entry->module)) {
 276                 err = -EFAULT;
 277                 goto __error1;
 278         }
 279         mode = file->f_flags & O_ACCMODE;
 280         if (mode == O_RDONLY || mode == O_RDWR) {
 281                 if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
 282                      !entry->c.text.read_size) ||
 283                     (entry->content == SNDRV_INFO_CONTENT_DATA &&
 284                      entry->c.ops->read == NULL)) {
 285                         err = -ENODEV;
 286                         goto __error;
 287                 }
 288         }
 289         if (mode == O_WRONLY || mode == O_RDWR) {
 290                 if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
 291                      !entry->c.text.write_size) ||
 292                     (entry->content == SNDRV_INFO_CONTENT_DATA &&
 293                      entry->c.ops->write == NULL)) {
 294                         err = -ENODEV;
 295                         goto __error;
 296                 }
 297         }
 298         data = kzalloc(sizeof(*data), GFP_KERNEL);
 299         if (data == NULL) {
 300                 err = -ENOMEM;
 301                 goto __error;
 302         }
 303         data->entry = entry;
 304         switch (entry->content) {
 305         case SNDRV_INFO_CONTENT_TEXT:
 306                 if (mode == O_RDONLY || mode == O_RDWR) {
 307                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 308                         if (buffer == NULL) {
 309                                 kfree(data);
 310                                 err = -ENOMEM;
 311                                 goto __error;
 312                         }
 313                         buffer->len = (entry->c.text.read_size +
 314                                       (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
 315                         buffer->buffer = vmalloc(buffer->len);
 316                         if (buffer->buffer == NULL) {
 317                                 kfree(buffer);
 318                                 kfree(data);
 319                                 err = -ENOMEM;
 320                                 goto __error;
 321                         }
 322                         buffer->curr = buffer->buffer;
 323                         data->rbuffer = buffer;
 324                 }
 325                 if (mode == O_WRONLY || mode == O_RDWR) {
 326                         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 327                         if (buffer == NULL) {
 328                                 if (mode == O_RDWR) {
 329                                         vfree(data->rbuffer->buffer);
 330                                         kfree(data->rbuffer);
 331                                 }
 332                                 kfree(data);
 333                                 err = -ENOMEM;
 334                                 goto __error;
 335                         }
 336                         buffer->len = (entry->c.text.write_size +
 337                                       (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
 338                         buffer->buffer = vmalloc(buffer->len);
 339                         if (buffer->buffer == NULL) {
 340                                 if (mode == O_RDWR) {
 341                                         vfree(data->rbuffer->buffer);
 342                                         kfree(data->rbuffer);
 343                                 }
 344                                 kfree(buffer);
 345                                 kfree(data);
 346                                 err = -ENOMEM;
 347                                 goto __error;
 348                         }
 349                         buffer->curr = buffer->buffer;
 350                         data->wbuffer = buffer;
 351                 }
 352                 break;
 353         case SNDRV_INFO_CONTENT_DATA:   /* data */
 354                 if (entry->c.ops->open) {
 355                         if ((err = entry->c.ops->open(entry, mode,
 356                                                       &data->file_private_data)) < 0) {
 357                                 kfree(data);
 358                                 goto __error;
 359                         }
 360                 }
 361                 break;
 362         }
 363         file->private_data = data;
 364         up(&info_mutex);
 365         if (entry->content == SNDRV_INFO_CONTENT_TEXT &&
 366             (mode == O_RDONLY || mode == O_RDWR)) {
 367                 if (entry->c.text.read) {
 368                         down(&entry->access);
 369                         entry->c.text.read(entry, data->rbuffer);
 370                         up(&entry->access);
 371                 }
 372         }
 373         return 0;
 374
 375       __error:
 376         module_put(entry->module);
 377       __error1:
 378         up(&info_mutex);
 379         return err;
 380 }
 381
 382 static int snd_info_entry_release(struct inode *inode, struct file *file)
 383 {
 384         struct snd_info_entry *entry;
 385         struct snd_info_private_data *data;
 386         int mode;
 387
 388         mode = file->f_flags & O_ACCMODE;
 389         data = file->private_data;
 390         entry = data->entry;
 391         switch (entry->content) {
 392         case SNDRV_INFO_CONTENT_TEXT:
 393                 if (mode == O_RDONLY || mode == O_RDWR) {
 394                         vfree(data->rbuffer->buffer);
 395                         kfree(data->rbuffer);
 396                 }
 397                 if (mode == O_WRONLY || mode == O_RDWR) {
 398                         if (entry->c.text.write) {
 399                                 entry->c.text.write(entry, data->wbuffer);
 400                                 if (data->wbuffer->error) {
 401                                         snd_printk(KERN_WARNING "data write error to %s (%i)\n",
 402                                                 entry->name,
 403                                                 data->wbuffer->error);
 404                                 }
 405                         }
 406                         vfree(data->wbuffer->buffer);
 407                         kfree(data->wbuffer);
 408                 }
 409                 break;
 410         case SNDRV_INFO_CONTENT_DATA:
 411                 if (entry->c.ops->release)
 412                         entry->c.ops->release(entry, mode,
 413                                               data->file_private_data);
 414                 break;
 415         }
 416         module_put(entry->module);
 417         kfree(data);
 418         return 0;
 419 }
 420
 421 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
 422 {
 423         struct snd_info_private_data *data;
 424         struct snd_info_entry *entry;
 425         unsigned int mask;
 426
 427         data = file->private_data;
 428         if (data == NULL)
 429                 return 0;
 430         entry = data->entry;
 431         mask = 0;
 432         switch (entry->content) {
 433         case SNDRV_INFO_CONTENT_DATA:
 434                 if (entry->c.ops->poll)
 435                         return entry->c.ops->poll(entry,
 436                                                   data->file_private_data,
 437                                                   file, wait);
 438                 if (entry->c.ops->read)
 439                         mask |= POLLIN | POLLRDNORM;
 440                 if (entry->c.ops->write)
 441                         mask |= POLLOUT | POLLWRNORM;
 442                 break;
 443         }
 444         return mask;
 445 }
 446
 447 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
 448                                 unsigned long arg)
 449 {
 450         struct snd_info_private_data *data;
 451         struct snd_info_entry *entry;
 452
 453         data = file->private_data;
 454         if (data == NULL)
 455                 return 0;
 456         entry = data->entry;
 457         switch (entry->content) {
 458         case SNDRV_INFO_CONTENT_DATA:
 459                 if (entry->c.ops->ioctl)
 460                         return entry->c.ops->ioctl(entry,
 461                                                    data->file_private_data,
 462                                                    file, cmd, arg);
 463                 break;
 464         }
 465         return -ENOTTY;
 466 }
 467
 468 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma)
 469 {
 470         struct inode *inode = file->f_dentry->d_inode;
 471         struct snd_info_private_data *data;
 472         struct snd_info_entry *entry;
 473
 474         data = file->private_data;
 475         if (data == NULL)
 476                 return 0;
 477         entry = data->entry;
 478         switch (entry->content) {
 479         case SNDRV_INFO_CONTENT_DATA:
 480                 if (entry->c.ops->mmap)
 481                         return entry->c.ops->mmap(entry,
 482                                                   data->file_private_data,
 483                                                   inode, file, vma);
 484                 break;
 485         }
 486         return -ENXIO;
 487 }
 488
 489 static struct file_operations snd_info_entry_operations =
 490 {
 491         .owner =                THIS_MODULE,
 492         .llseek =               snd_info_entry_llseek,
 493         .read =                 snd_info_entry_read,
 494         .write =                snd_info_entry_write,
 495         .poll =                 snd_info_entry_poll,
 496         .unlocked_ioctl =       snd_info_entry_ioctl,
 497         .mmap =                 snd_info_entry_mmap,
 498         .open =                 snd_info_entry_open,
 499         .release =              snd_info_entry_release,
 500 };
 501
 502 /**
 503  * snd_create_proc_entry - create a procfs entry
 504  * @name: the name of the proc file
 505  * @mode: the file permission bits, S_Ixxx
 506  * @parent: the parent proc-directory entry
 507  *
 508  * Creates a new proc file entry with the given name and permission
 509  * on the given directory.
 510  *
 511  * Returns the pointer of new instance or NULL on failure.
 512  */
 513 static struct proc_dir_entry *snd_create_proc_entry(const char *name, mode_t mode,
 514                                                     struct proc_dir_entry *parent)
 515 {
 516         struct proc_dir_entry *p;
 517         p = create_proc_entry(name, mode, parent);
 518         if (p)
 519                 snd_info_entry_prepare(p);
 520         return p;
 521 }
 522
 523 int __init snd_info_init(void)
 524 {
 525         struct proc_dir_entry *p;
 526
 527         p = snd_create_proc_entry("asound", S_IFDIR | S_IRUGO | S_IXUGO, &proc_root);
 528         if (p == NULL)
 529                 return -ENOMEM;
 530         snd_proc_root = p;
 531 #ifdef CONFIG_SND_OSSEMUL
 532         {
 533                 struct snd_info_entry *entry;
 534                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL)
 535                         return -ENOMEM;
 536                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 537                 if (snd_info_register(entry) < 0) {
 538                         snd_info_free_entry(entry);
 539                         return -ENOMEM;
 540                 }
 541                 snd_oss_root = entry;
 542         }
 543 #endif
 544 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 545         {
 546                 struct snd_info_entry *entry;
 547                 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL)
 548                         return -ENOMEM;
 549                 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 550                 if (snd_info_register(entry) < 0) {
 551                         snd_info_free_entry(entry);
 552                         return -ENOMEM;
 553                 }
 554                 snd_seq_root = entry;
 555         }
 556 #endif
 557         snd_info_version_init();
 558         snd_minor_info_init();
 559         snd_minor_info_oss_init();
 560         snd_card_info_init();
 561         return 0;
 562 }
 563
 564 int __exit snd_info_done(void)
 565 {
 566         snd_card_info_done();
 567         snd_minor_info_oss_done();
 568         snd_minor_info_done();
 569         snd_info_version_done();
 570         if (snd_proc_root) {
 571 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
 572                 snd_info_unregister(snd_seq_root);
 573 #endif
 574 #ifdef CONFIG_SND_OSSEMUL
 575                 snd_info_unregister(snd_oss_root);
 576 #endif
 577                 snd_remove_proc_entry(&proc_root, snd_proc_root);
 578         }
 579         return 0;
 580 }
 581
 582 /*
 583
 584  */
 585
 586
 587 /*
 588  * create a card proc file
 589  * called from init.c
 590  */
 591 int snd_info_card_create(struct snd_card *card)
 592 {
 593         char str[8];
 594         struct snd_info_entry *entry;
 595
 596         snd_assert(card != NULL, return -ENXIO);
 597
 598         sprintf(str, "card%i", card->number);
 599         if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL)
 600                 return -ENOMEM;
 601         entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 602         if (snd_info_register(entry) < 0) {
 603                 snd_info_free_entry(entry);
 604                 return -ENOMEM;
 605         }
 606         card->proc_root = entry;
 607         return 0;
 608 }
 609
 610 /*
 611  * register the card proc file
 612  * called from init.c
 613  */
 614 int snd_info_card_register(struct snd_card *card)
 615 {
 616         struct proc_dir_entry *p;
 617
 618         snd_assert(card != NULL, return -ENXIO);
 619
 620         if (!strcmp(card->id, card->proc_root->name))
 621                 return 0;
 622
 623         p = proc_symlink(card->id, snd_proc_root, card->proc_root->name);
 624         if (p == NULL)
 625                 return -ENOMEM;
 626         card->proc_root_link = p;
 627         return 0;
 628 }
 629
 630 /*
 631  * de-register the card proc file
 632  * called from init.c
 633  */
 634 int snd_info_card_free(struct snd_card *card)
 635 {
 636         snd_assert(card != NULL, return -ENXIO);
 637         if (card->proc_root_link) {
 638                 snd_remove_proc_entry(snd_proc_root, card->proc_root_link);
 639                 card->proc_root_link = NULL;
 640         }
 641         if (card->proc_root) {
 642                 snd_info_unregister(card->proc_root);
 643                 card->proc_root = NULL;
 644         }
 645         return 0;
 646 }
 647
 648
 649 /**
 650  * snd_info_get_line - read one line from the procfs buffer
 651  * @buffer: the procfs buffer
 652  * @line: the buffer to store
 653  * @len: the max. buffer size - 1
 654  *
 655  * Reads one line from the buffer and stores the string.
 656  *
 657  * Returns zero if successful, or 1 if error or EOF.
 658  */
 659 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len)
 660 {
 661         int c = -1;
 662
 663         if (len <= 0 || buffer->stop || buffer->error)
 664                 return 1;
 665         while (--len > 0) {
 666                 c = *buffer->curr++;
 667                 if (c == '\n') {
 668                         if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 669                                 buffer->stop = 1;
 670                         }
 671                         break;
 672                 }
 673                 *line++ = c;
 674                 if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 675                         buffer->stop = 1;
 676                         break;
 677                 }
 678         }
 679         while (c != '\n' && !buffer->stop) {
 680                 c = *buffer->curr++;
 681                 if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
 682                         buffer->stop = 1;
 683                 }
 684         }
 685         *line = '\0';
 686         return 0;
 687 }
 688
 689 /**
 690  * snd_info_get_str - parse a string token
 691  * @dest: the buffer to store the string token
 692  * @src: the original string
 693  * @len: the max. length of token - 1
 694  *
 695  * Parses the original string and copy a token to the given
 696  * string buffer.
 697  *
 698  * Returns the updated pointer of the original string so that
 699  * it can be used for the next call.
 700  */
 701 char *snd_info_get_str(char *dest, char *src, int len)
 702 {
 703         int c;
 704
 705         while (*src == ' ' || *src == '\t')
 706                 src++;
 707         if (*src == '"' || *src == '\'') {
 708                 c = *src++;
 709                 while (--len > 0 && *src && *src != c) {
 710                         *dest++ = *src++;
 711                 }
 712                 if (*src == c)
 713                         src++;
 714         } else {
 715                 while (--len > 0 && *src && *src != ' ' && *src != '\t') {
 716                         *dest++ = *src++;
 717                 }
 718         }
 719         *dest = 0;
 720         while (*src == ' ' || *src == '\t')
 721                 src++;
 722         return src;
 723 }
 724
 725 /**
 726  * snd_info_create_entry - create an info entry
 727  * @name: the proc file name
 728  *
 729  * Creates an info entry with the given file name and initializes as
 730  * the default state.
 731  *
 732  * Usually called from other functions such as
 733  * snd_info_create_card_entry().
 734  *
 735  * Returns the pointer of the new instance, or NULL on failure.
 736  */
 737 static struct snd_info_entry *snd_info_create_entry(const char *name)
 738 {
 739         struct snd_info_entry *entry;
 740         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 741         if (entry == NULL)
 742                 return NULL;
 743         entry->name = kstrdup(name, GFP_KERNEL);
 744         if (entry->name == NULL) {
 745                 kfree(entry);
 746                 return NULL;
 747         }
 748         entry->mode = S_IFREG | S_IRUGO;
 749         entry->content = SNDRV_INFO_CONTENT_TEXT;
 750         init_MUTEX(&entry->access);
 751         return entry;
 752 }
 753
 754 /**
 755  * snd_info_create_module_entry - create an info entry for the given module
 756  * @module: the module pointer
 757  * @name: the file name
 758  * @parent: the parent directory
 759  *
 760  * Creates a new info entry and assigns it to the given module.
 761  *
 762  * Returns the pointer of the new instance, or NULL on failure.
 763  */
 764 struct snd_info_entry *snd_info_create_module_entry(struct module * module,
 765                                                const char *name,
 766                                                struct snd_info_entry *parent)
 767 {
 768         struct snd_info_entry *entry = snd_info_create_entry(name);
 769         if (entry) {
 770                 entry->module = module;
 771                 entry->parent = parent;
 772         }
 773         return entry;
 774 }
 775
 776 /**
 777  * snd_info_create_card_entry - create an info entry for the given card
 778  * @card: the card instance
 779  * @name: the file name
 780  * @parent: the parent directory
 781  *
 782  * Creates a new info entry and assigns it to the given card.
 783  *
 784  * Returns the pointer of the new instance, or NULL on failure.
 785  */
 786 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card,
 787                                              const char *name,
 788                                              struct snd_info_entry * parent)
 789 {
 790         struct snd_info_entry *entry = snd_info_create_entry(name);
 791         if (entry) {
 792                 entry->module = card->module;
 793                 entry->card = card;
 794                 entry->parent = parent;
 795         }
 796         return entry;
 797 }
 798
 799 static int snd_info_dev_free_entry(struct snd_device *device)
 800 {
 801         struct snd_info_entry *entry = device->device_data;
 802         snd_info_free_entry(entry);
 803         return 0;
 804 }
 805
 806 static int snd_info_dev_register_entry(struct snd_device *device)
 807 {
 808         struct snd_info_entry *entry = device->device_data;
 809         return snd_info_register(entry);
 810 }
 811
 812 static int snd_info_dev_disconnect_entry(struct snd_device *device)
 813 {
 814         struct snd_info_entry *entry = device->device_data;
 815         entry->disconnected = 1;
 816         return 0;
 817 }
 818
 819 static int snd_info_dev_unregister_entry(struct snd_device *device)
 820 {
 821         struct snd_info_entry *entry = device->device_data;
 822         return snd_info_unregister(entry);
 823 }
 824
 825 /**
 826  * snd_card_proc_new - create an info entry for the given card
 827  * @card: the card instance
 828  * @name: the file name
 829  * @entryp: the pointer to store the new info entry
 830  *
 831  * Creates a new info entry and assigns it to the given card.
 832  * Unlike snd_info_create_card_entry(), this function registers the
 833  * info entry as an ALSA device component, so that it can be
 834  * unregistered/released without explicit call.
 835  * Also, you don't have to register this entry via snd_info_register(),
 836  * since this will be registered by snd_card_register() automatically.
 837  *
 838  * The parent is assumed as card->proc_root.
 839  *
 840  * For releasing this entry, use snd_device_free() instead of
 841  * snd_info_free_entry().
 842  *
 843  * Returns zero if successful, or a negative error code on failure.
 844  */
 845 int snd_card_proc_new(struct snd_card *card, const char *name,
 846                       struct snd_info_entry **entryp)
 847 {
 848         static struct snd_device_ops ops = {
 849                 .dev_free = snd_info_dev_free_entry,
 850                 .dev_register = snd_info_dev_register_entry,
 851                 .dev_disconnect = snd_info_dev_disconnect_entry,
 852                 .dev_unregister = snd_info_dev_unregister_entry
 853         };
 854         struct snd_info_entry *entry;
 855         int err;
 856
 857         entry = snd_info_create_card_entry(card, name, card->proc_root);
 858         if (! entry)
 859                 return -ENOMEM;
 860         if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {
 861                 snd_info_free_entry(entry);
 862                 return err;
 863         }
 864         if (entryp)
 865                 *entryp = entry;
 866         return 0;
 867 }
 868
 869 /**
 870  * snd_info_free_entry - release the info entry
 871  * @entry: the info entry
 872  *
 873  * Releases the info entry.  Don't call this after registered.
 874  */
 875 void snd_info_free_entry(struct snd_info_entry * entry)
 876 {
 877         if (entry == NULL)
 878                 return;
 879         kfree(entry->name);
 880         if (entry->private_free)
 881                 entry->private_free(entry);
 882         kfree(entry);
 883 }
 884
 885 /**
 886  * snd_info_register - register the info entry
 887  * @entry: the info entry
 888  *
 889  * Registers the proc info entry.
 890  *
 891  * Returns zero if successful, or a negative error code on failure.
 892  */
 893 int snd_info_register(struct snd_info_entry * entry)
 894 {
 895         struct proc_dir_entry *root, *p = NULL;
 896
 897         snd_assert(entry != NULL, return -ENXIO);
 898         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 899         down(&info_mutex);
 900         p = snd_create_proc_entry(entry->name, entry->mode, root);
 901         if (!p) {
 902                 up(&info_mutex);
 903                 return -ENOMEM;
 904         }
 905         p->owner = entry->module;
 906         if (!S_ISDIR(entry->mode))
 907                 p->proc_fops = &snd_info_entry_operations;
 908         p->size = entry->size;
 909         p->data = entry;
 910         entry->p = p;
 911         up(&info_mutex);
 912         return 0;
 913 }
 914
 915 /**
 916  * snd_info_unregister - de-register the info entry
 917  * @entry: the info entry
 918  *
 919  * De-registers the info entry and releases the instance.
 920  *
 921  * Returns zero if successful, or a negative error code on failure.
 922  */
 923 int snd_info_unregister(struct snd_info_entry * entry)
 924 {
 925         struct proc_dir_entry *root;
 926
 927         if (! entry)
 928                 return 0;
 929         snd_assert(entry->p != NULL, return -ENXIO);
 930         root = entry->parent == NULL ? snd_proc_root : entry->parent->p;
 931         snd_assert(root, return -ENXIO);
 932         down(&info_mutex);
 933         snd_remove_proc_entry(root, entry->p);
 934         up(&info_mutex);
 935         snd_info_free_entry(entry);
 936         return 0;
 937 }
 938
 939 /*
 940
 941  */
 942
 943 static struct snd_info_entry *snd_info_version_entry = NULL;
 944
 945 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
 946 {
 947         snd_iprintf(buffer,
 948                     "Advanced Linux Sound Architecture Driver Version "
 949                     CONFIG_SND_VERSION CONFIG_SND_DATE ".\n"
 950                    );
 951 }
 952
 953 static int __init snd_info_version_init(void)
 954 {
 955         struct snd_info_entry *entry;
 956
 957         entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
 958         if (entry == NULL)
 959                 return -ENOMEM;
 960         entry->c.text.read_size = 256;
 961         entry->c.text.read = snd_info_version_read;
 962         if (snd_info_register(entry) < 0) {
 963                 snd_info_free_entry(entry);
 964                 return -ENOMEM;
 965         }
 966         snd_info_version_entry = entry;
 967         return 0;
 968 }
 969
 970 static int __exit snd_info_version_done(void)
 971 {
 972         if (snd_info_version_entry)
 973                 snd_info_unregister(snd_info_version_entry);
 974         return 0;
 975 }
 976
 977 #endif /* CONFIG_PROC_FS */