sound/core/init.c

   1 /*
   2  *  Initialization routines
   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/sched.h>
  24 #include <linux/module.h>
  25 #include <linux/file.h>
  26 #include <linux/slab.h>
  27 #include <linux/time.h>
  28 #include <linux/ctype.h>
  29 #include <linux/pm.h>
  30
  31 #include <sound/core.h>
  32 #include <sound/control.h>
  33 #include <sound/info.h>
  34
  35 /* monitor files for graceful shutdown (hotplug) */
  36 struct snd_monitor_file {
  37         struct file *file;
  38         const struct file_operations *disconnected_f_op;
  39         struct list_head shutdown_list; /* still need to shutdown */
  40         struct list_head list;  /* link of monitor files */
  41 };
  42
  43 static DEFINE_SPINLOCK(shutdown_lock);
  44 static LIST_HEAD(shutdown_files);
  45
  46 static const struct file_operations snd_shutdown_f_ops;
  47
  48 static unsigned int snd_cards_lock;     /* locked for registering/using */
  49 struct snd_card *snd_cards[SNDRV_CARDS];
  50 EXPORT_SYMBOL(snd_cards);
  51
  52 static DEFINE_MUTEX(snd_card_mutex);
  53
  54 static char *slots[SNDRV_CARDS];
  55 module_param_array(slots, charp, NULL, 0444);
  56 MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
  57
  58 /* return non-zero if the given index is reserved for the given
  59  * module via slots option
  60  */
  61 static int module_slot_match(struct module *module, int idx)
  62 {
  63         int match = 1;
  64 #ifdef MODULE
  65         const char *s1, *s2;
  66
  67         if (!module || !module->name || !slots[idx])
  68                 return 0;
  69
  70         s1 = module->name;
  71         s2 = slots[idx];
  72         if (*s2 == '!') {
  73                 match = 0; /* negative match */
  74                 s2++;
  75         }
  76         /* compare module name strings
  77          * hyphens are handled as equivalent with underscore
  78          */
  79         for (;;) {
  80                 char c1 = *s1++;
  81                 char c2 = *s2++;
  82                 if (c1 == '-')
  83                         c1 = '_';
  84                 if (c2 == '-')
  85                         c2 = '_';
  86                 if (c1 != c2)
  87                         return !match;
  88                 if (!c1)
  89                         break;
  90         }
  91 #endif /* MODULE */
  92         return match;
  93 }
  94
  95 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
  96 int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
  97 EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
  98 #endif
  99
 100 #ifdef CONFIG_PROC_FS
 101 static void snd_card_id_read(struct snd_info_entry *entry,
 102                              struct snd_info_buffer *buffer)
 103 {
 104         snd_iprintf(buffer, "%s\n", entry->card->id);
 105 }
 106
 107 static inline int init_info_for_card(struct snd_card *card)
 108 {
 109         int err;
 110         struct snd_info_entry *entry;
 111
 112         if ((err = snd_info_card_register(card)) < 0) {
 113                 snd_printd("unable to create card info\n");
 114                 return err;
 115         }
 116         if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
 117                 snd_printd("unable to create card entry\n");
 118                 return err;
 119         }
 120         entry->c.text.read = snd_card_id_read;
 121         if (snd_info_register(entry) < 0) {
 122                 snd_info_free_entry(entry);
 123                 entry = NULL;
 124         }
 125         card->proc_id = entry;
 126         return 0;
 127 }
 128 #else /* !CONFIG_PROC_FS */
 129 #define init_info_for_card(card)
 130 #endif
 131
 132 /**
 133  *  snd_card_create - create and initialize a soundcard structure
 134  *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
 135  *  @xid: card identification (ASCII string)
 136  *  @module: top level module for locking
 137  *  @extra_size: allocate this extra size after the main soundcard structure
 138  *  @card_ret: the pointer to store the created card instance
 139  *
 140  *  Creates and initializes a soundcard structure.
 141  *
 142  *  The function allocates snd_card instance via kzalloc with the given
 143  *  space for the driver to use freely.  The allocated struct is stored
 144  *  in the given card_ret pointer.
 145  *
 146  *  Returns zero if successful or a negative error code.
 147  */
 148 int snd_card_create(int idx, const char *xid,
 149                     struct module *module, int extra_size,
 150                     struct snd_card **card_ret)
 151 {
 152         struct snd_card *card;
 153         int err, idx2;
 154
 155         if (snd_BUG_ON(!card_ret))
 156                 return -EINVAL;
 157         *card_ret = NULL;
 158
 159         if (extra_size < 0)
 160                 extra_size = 0;
 161         card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
 162         if (!card)
 163                 return -ENOMEM;
 164         if (xid)
 165                 strlcpy(card->id, xid, sizeof(card->id));
 166         err = 0;
 167         mutex_lock(&snd_card_mutex);
 168         if (idx < 0) {
 169                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
 170                         /* idx == -1 == 0xffff means: take any free slot */
 171                         if (~snd_cards_lock & idx & 1<<idx2) {
 172                                 if (module_slot_match(module, idx2)) {
 173                                         idx = idx2;
 174                                         break;
 175                                 }
 176                         }
 177         }
 178         if (idx < 0) {
 179                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
 180                         /* idx == -1 == 0xffff means: take any free slot */
 181                         if (~snd_cards_lock & idx & 1<<idx2) {
 182                                 if (!slots[idx2] || !*slots[idx2]) {
 183                                         idx = idx2;
 184                                         break;
 185                                 }
 186                         }
 187         }
 188         if (idx < 0)
 189                 err = -ENODEV;
 190         else if (idx < snd_ecards_limit) {
 191                 if (snd_cards_lock & (1 << idx))
 192                         err = -EBUSY;   /* invalid */
 193         } else if (idx >= SNDRV_CARDS)
 194                 err = -ENODEV;
 195         if (err < 0) {
 196                 mutex_unlock(&snd_card_mutex);
 197                 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
 198                          idx, snd_ecards_limit - 1, err);
 199                 goto __error;
 200         }
 201         snd_cards_lock |= 1 << idx;             /* lock it */
 202         if (idx >= snd_ecards_limit)
 203                 snd_ecards_limit = idx + 1; /* increase the limit */
 204         mutex_unlock(&snd_card_mutex);
 205         card->number = idx;
 206         card->module = module;
 207         INIT_LIST_HEAD(&card->devices);
 208         init_rwsem(&card->controls_rwsem);
 209         rwlock_init(&card->ctl_files_rwlock);
 210         INIT_LIST_HEAD(&card->controls);
 211         INIT_LIST_HEAD(&card->ctl_files);
 212         spin_lock_init(&card->files_lock);
 213         INIT_LIST_HEAD(&card->files_list);
 214         init_waitqueue_head(&card->shutdown_sleep);
 215 #ifdef CONFIG_PM
 216         mutex_init(&card->power_lock);
 217         init_waitqueue_head(&card->power_sleep);
 218 #endif
 219         /* the control interface cannot be accessed from the user space until */
 220         /* snd_cards_bitmask and snd_cards are set with snd_card_register */
 221         err = snd_ctl_create(card);
 222         if (err < 0) {
 223                 snd_printk(KERN_ERR "unable to register control minors\n");
 224                 goto __error;
 225         }
 226         err = snd_info_card_create(card);
 227         if (err < 0) {
 228                 snd_printk(KERN_ERR "unable to create card info\n");
 229                 goto __error_ctl;
 230         }
 231         if (extra_size > 0)
 232                 card->private_data = (char *)card + sizeof(struct snd_card);
 233         *card_ret = card;
 234         return 0;
 235
 236       __error_ctl:
 237         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
 238       __error:
 239         kfree(card);
 240         return err;
 241 }
 242 EXPORT_SYMBOL(snd_card_create);
 243
 244 /* return non-zero if a card is already locked */
 245 int snd_card_locked(int card)
 246 {
 247         int locked;
 248
 249         mutex_lock(&snd_card_mutex);
 250         locked = snd_cards_lock & (1 << card);
 251         mutex_unlock(&snd_card_mutex);
 252         return locked;
 253 }
 254
 255 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
 256 {
 257         return -ENODEV;
 258 }
 259
 260 static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
 261                                    size_t count, loff_t *offset)
 262 {
 263         return -ENODEV;
 264 }
 265
 266 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
 267                                     size_t count, loff_t *offset)
 268 {
 269         return -ENODEV;
 270 }
 271
 272 static int snd_disconnect_release(struct inode *inode, struct file *file)
 273 {
 274         struct snd_monitor_file *df = NULL, *_df;
 275
 276         spin_lock(&shutdown_lock);
 277         list_for_each_entry(_df, &shutdown_files, shutdown_list) {
 278                 if (_df->file == file) {
 279                         df = _df;
 280                         list_del_init(&df->shutdown_list);
 281                         break;
 282                 }
 283         }
 284         spin_unlock(&shutdown_lock);
 285
 286         if (likely(df)) {
 287                 if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
 288                         df->disconnected_f_op->fasync(-1, file, 0);
 289                 return df->disconnected_f_op->release(inode, file);
 290         }
 291
 292         panic("%s(%p, %p) failed!", __func__, inode, file);
 293 }
 294
 295 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 296 {
 297         return POLLERR | POLLNVAL;
 298 }
 299
 300 static long snd_disconnect_ioctl(struct file *file,
 301                                  unsigned int cmd, unsigned long arg)
 302 {
 303         return -ENODEV;
 304 }
 305
 306 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
 307 {
 308         return -ENODEV;
 309 }
 310
 311 static int snd_disconnect_fasync(int fd, struct file *file, int on)
 312 {
 313         return -ENODEV;
 314 }
 315
 316 static const struct file_operations snd_shutdown_f_ops =
 317 {
 318         .owner =        THIS_MODULE,
 319         .llseek =       snd_disconnect_llseek,
 320         .read =         snd_disconnect_read,
 321         .write =        snd_disconnect_write,
 322         .release =      snd_disconnect_release,
 323         .poll =         snd_disconnect_poll,
 324         .unlocked_ioctl = snd_disconnect_ioctl,
 325 #ifdef CONFIG_COMPAT
 326         .compat_ioctl = snd_disconnect_ioctl,
 327 #endif
 328         .mmap =         snd_disconnect_mmap,
 329         .fasync =       snd_disconnect_fasync
 330 };
 331
 332 /**
 333  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 334  *  @card: soundcard structure
 335  *
 336  *  Disconnects all APIs from the file-operations (user space).
 337  *
 338  *  Returns zero, otherwise a negative error code.
 339  *
 340  *  Note: The current implementation replaces all active file->f_op with special
 341  *        dummy file operations (they do nothing except release).
 342  */
 343 int snd_card_disconnect(struct snd_card *card)
 344 {
 345         struct snd_monitor_file *mfile;
 346         int err;
 347
 348         if (!card)
 349                 return -EINVAL;
 350
 351         spin_lock(&card->files_lock);
 352         if (card->shutdown) {
 353                 spin_unlock(&card->files_lock);
 354                 return 0;
 355         }
 356         card->shutdown = 1;
 357         spin_unlock(&card->files_lock);
 358
 359         /* phase 1: disable fops (user space) operations for ALSA API */
 360         mutex_lock(&snd_card_mutex);
 361         snd_cards[card->number] = NULL;
 362         snd_cards_lock &= ~(1 << card->number);
 363         mutex_unlock(&snd_card_mutex);
 364
 365         /* phase 2: replace file->f_op with special dummy operations */
 366
 367         spin_lock(&card->files_lock);
 368         list_for_each_entry(mfile, &card->files_list, list) {
 369                 /* it's critical part, use endless loop */
 370                 /* we have no room to fail */
 371                 mfile->disconnected_f_op = mfile->file->f_op;
 372
 373                 spin_lock(&shutdown_lock);
 374                 list_add(&mfile->shutdown_list, &shutdown_files);
 375                 spin_unlock(&shutdown_lock);
 376
 377                 mfile->file->f_op = &snd_shutdown_f_ops;
 378                 fops_get(mfile->file->f_op);
 379         }
 380         spin_unlock(&card->files_lock);
 381
 382         /* phase 3: notify all connected devices about disconnection */
 383         /* at this point, they cannot respond to any calls except release() */
 384
 385 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 386         if (snd_mixer_oss_notify_callback)
 387                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
 388 #endif
 389
 390         /* notify all devices that we are disconnected */
 391         err = snd_device_disconnect_all(card);
 392         if (err < 0)
 393                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
 394
 395         snd_info_card_disconnect(card);
 396         if (card->card_dev) {
 397                 device_unregister(card->card_dev);
 398                 card->card_dev = NULL;
 399         }
 400 #ifdef CONFIG_PM
 401         wake_up(&card->power_sleep);
 402 #endif
 403         return 0;
 404 }
 405
 406 EXPORT_SYMBOL(snd_card_disconnect);
 407
 408 /**
 409  *  snd_card_free - frees given soundcard structure
 410  *  @card: soundcard structure
 411  *
 412  *  This function releases the soundcard structure and the all assigned
 413  *  devices automatically.  That is, you don't have to release the devices
 414  *  by yourself.
 415  *
 416  *  Returns zero. Frees all associated devices and frees the control
 417  *  interface associated to given soundcard.
 418  */
 419 static int snd_card_do_free(struct snd_card *card)
 420 {
 421 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 422         if (snd_mixer_oss_notify_callback)
 423                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
 424 #endif
 425         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
 426                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
 427                 /* Fatal, but this situation should never occur */
 428         }
 429         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
 430                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
 431                 /* Fatal, but this situation should never occur */
 432         }
 433         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
 434                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
 435                 /* Fatal, but this situation should never occur */
 436         }
 437         if (card->private_free)
 438                 card->private_free(card);
 439         snd_info_free_entry(card->proc_id);
 440         if (snd_info_card_free(card) < 0) {
 441                 snd_printk(KERN_WARNING "unable to free card info\n");
 442                 /* Not fatal error */
 443         }
 444         kfree(card);
 445         return 0;
 446 }
 447
 448 int snd_card_free_when_closed(struct snd_card *card)
 449 {
 450         int free_now = 0;
 451         int ret = snd_card_disconnect(card);
 452         if (ret)
 453                 return ret;
 454
 455         spin_lock(&card->files_lock);
 456         if (list_empty(&card->files_list))
 457                 free_now = 1;
 458         else
 459                 card->free_on_last_close = 1;
 460         spin_unlock(&card->files_lock);
 461
 462         if (free_now)
 463                 snd_card_do_free(card);
 464         return 0;
 465 }
 466
 467 EXPORT_SYMBOL(snd_card_free_when_closed);
 468
 469 int snd_card_free(struct snd_card *card)
 470 {
 471         int ret = snd_card_disconnect(card);
 472         if (ret)
 473                 return ret;
 474
 475         /* wait, until all devices are ready for the free operation */
 476         wait_event(card->shutdown_sleep, list_empty(&card->files_list));
 477         snd_card_do_free(card);
 478         return 0;
 479 }
 480
 481 EXPORT_SYMBOL(snd_card_free);
 482
 483 static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
 484 {
 485         int i, len, idx_flag = 0, loops = SNDRV_CARDS;
 486         const char *spos, *src;
 487         char *id;
 488
 489         if (nid == NULL) {
 490                 id = card->shortname;
 491                 spos = src = id;
 492                 while (*id != '\0') {
 493                         if (*id == ' ')
 494                                 spos = id + 1;
 495                         id++;
 496                 }
 497         } else {
 498                 spos = src = nid;
 499         }
 500         id = card->id;
 501         while (*spos != '\0' && !isalnum(*spos))
 502                 spos++;
 503         if (isdigit(*spos))
 504                 *id++ = isalpha(src[0]) ? src[0] : 'D';
 505         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
 506                 if (isalnum(*spos))
 507                         *id++ = *spos;
 508                 spos++;
 509         }
 510         *id = '\0';
 511
 512         id = card->id;
 513
 514         if (*id == '\0')
 515                 strcpy(id, "Default");
 516
 517         while (1) {
 518                 if (loops-- == 0) {
 519                         snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
 520                         strcpy(card->id, card->proc_root->name);
 521                         return;
 522                 }
 523                 if (!snd_info_check_reserved_words(id))
 524                         goto __change;
 525                 for (i = 0; i < snd_ecards_limit; i++) {
 526                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
 527                                 goto __change;
 528                 }
 529                 break;
 530
 531               __change:
 532                 len = strlen(id);
 533                 if (idx_flag) {
 534                         if (id[len-1] != '9')
 535                                 id[len-1]++;
 536                         else
 537                                 id[len-1] = 'A';
 538                 } else if ((size_t)len <= sizeof(card->id) - 3) {
 539                         strcat(id, "_1");
 540                         idx_flag++;
 541                 } else {
 542                         spos = id + len - 2;
 543                         if ((size_t)len <= sizeof(card->id) - 2)
 544                                 spos++;
 545                         *(char *)spos++ = '_';
 546                         *(char *)spos++ = '1';
 547                         *(char *)spos++ = '\0';
 548                         idx_flag++;
 549                 }
 550         }
 551 }
 552
 553 /**
 554  *  snd_card_set_id - set card identification name
 555  *  @card: soundcard structure
 556  *  @nid: new identification string
 557  *
 558  *  This function sets the card identification and checks for name
 559  *  collisions.
 560  */
 561 void snd_card_set_id(struct snd_card *card, const char *nid)
 562 {
 563         /* check if user specified own card->id */
 564         if (card->id[0] != '\0')
 565                 return;
 566         mutex_lock(&snd_card_mutex);
 567         snd_card_set_id_no_lock(card, nid);
 568         mutex_unlock(&snd_card_mutex);
 569 }
 570 EXPORT_SYMBOL(snd_card_set_id);
 571
 572 static ssize_t
 573 card_id_show_attr(struct device *dev,
 574                   struct device_attribute *attr, char *buf)
 575 {
 576         struct snd_card *card = dev_get_drvdata(dev);
 577         return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
 578 }
 579
 580 static ssize_t
 581 card_id_store_attr(struct device *dev, struct device_attribute *attr,
 582                    const char *buf, size_t count)
 583 {
 584         struct snd_card *card = dev_get_drvdata(dev);
 585         char buf1[sizeof(card->id)];
 586         size_t copy = count > sizeof(card->id) - 1 ?
 587                                         sizeof(card->id) - 1 : count;
 588         size_t idx;
 589         int c;
 590
 591         for (idx = 0; idx < copy; idx++) {
 592                 c = buf[idx];
 593                 if (!isalnum(c) && c != '_' && c != '-')
 594                         return -EINVAL;
 595         }
 596         memcpy(buf1, buf, copy);
 597         buf1[copy] = '\0';
 598         mutex_lock(&snd_card_mutex);
 599         if (!snd_info_check_reserved_words(buf1)) {
 600              __exist:
 601                 mutex_unlock(&snd_card_mutex);
 602                 return -EEXIST;
 603         }
 604         for (idx = 0; idx < snd_ecards_limit; idx++) {
 605                 if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
 606                         if (card == snd_cards[idx])
 607                                 goto __ok;
 608                         else
 609                                 goto __exist;
 610                 }
 611         }
 612         strcpy(card->id, buf1);
 613         snd_info_card_id_change(card);
 614 __ok:
 615         mutex_unlock(&snd_card_mutex);
 616
 617         return count;
 618 }
 619
 620 static struct device_attribute card_id_attrs =
 621         __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
 622
 623 static ssize_t
 624 card_number_show_attr(struct device *dev,
 625                      struct device_attribute *attr, char *buf)
 626 {
 627         struct snd_card *card = dev_get_drvdata(dev);
 628         return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
 629 }
 630
 631 static struct device_attribute card_number_attrs =
 632         __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 633
 634 /**
 635  *  snd_card_register - register the soundcard
 636  *  @card: soundcard structure
 637  *
 638  *  This function registers all the devices assigned to the soundcard.
 639  *  Until calling this, the ALSA control interface is blocked from the
 640  *  external accesses.  Thus, you should call this function at the end
 641  *  of the initialization of the card.
 642  *
 643  *  Returns zero otherwise a negative error code if the registration failed.
 644  */
 645 int snd_card_register(struct snd_card *card)
 646 {
 647         int err;
 648
 649         if (snd_BUG_ON(!card))
 650                 return -EINVAL;
 651
 652         if (!card->card_dev) {
 653                 card->card_dev = device_create(sound_class, card->dev,
 654                                                MKDEV(0, 0), card,
 655                                                "card%i", card->number);
 656                 if (IS_ERR(card->card_dev))
 657                         card->card_dev = NULL;
 658         }
 659
 660         if ((err = snd_device_register_all(card)) < 0)
 661                 return err;
 662         mutex_lock(&snd_card_mutex);
 663         if (snd_cards[card->number]) {
 664                 /* already registered */
 665                 mutex_unlock(&snd_card_mutex);
 666                 return 0;
 667         }
 668         snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
 669         snd_cards[card->number] = card;
 670         mutex_unlock(&snd_card_mutex);
 671         init_info_for_card(card);
 672 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 673         if (snd_mixer_oss_notify_callback)
 674                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
 675 #endif
 676         if (card->card_dev) {
 677                 err = device_create_file(card->card_dev, &card_id_attrs);
 678                 if (err < 0)
 679                         return err;
 680                 err = device_create_file(card->card_dev, &card_number_attrs);
 681                 if (err < 0)
 682                         return err;
 683         }
 684
 685         return 0;
 686 }
 687
 688 EXPORT_SYMBOL(snd_card_register);
 689
 690 #ifdef CONFIG_PROC_FS
 691 static struct snd_info_entry *snd_card_info_entry;
 692
 693 static void snd_card_info_read(struct snd_info_entry *entry,
 694                                struct snd_info_buffer *buffer)
 695 {
 696         int idx, count;
 697         struct snd_card *card;
 698
 699         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 700                 mutex_lock(&snd_card_mutex);
 701                 if ((card = snd_cards[idx]) != NULL) {
 702                         count++;
 703                         snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
 704                                         idx,
 705                                         card->id,
 706                                         card->driver,
 707                                         card->shortname);
 708                         snd_iprintf(buffer, "                      %s\n",
 709                                         card->longname);
 710                 }
 711                 mutex_unlock(&snd_card_mutex);
 712         }
 713         if (!count)
 714                 snd_iprintf(buffer, "--- no soundcards ---\n");
 715 }
 716
 717 #ifdef CONFIG_SND_OSSEMUL
 718
 719 void snd_card_info_read_oss(struct snd_info_buffer *buffer)
 720 {
 721         int idx, count;
 722         struct snd_card *card;
 723
 724         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 725                 mutex_lock(&snd_card_mutex);
 726                 if ((card = snd_cards[idx]) != NULL) {
 727                         count++;
 728                         snd_iprintf(buffer, "%s\n", card->longname);
 729                 }
 730                 mutex_unlock(&snd_card_mutex);
 731         }
 732         if (!count) {
 733                 snd_iprintf(buffer, "--- no soundcards ---\n");
 734         }
 735 }
 736
 737 #endif
 738
 739 #ifdef MODULE
 740 static struct snd_info_entry *snd_card_module_info_entry;
 741 static void snd_card_module_info_read(struct snd_info_entry *entry,
 742                                       struct snd_info_buffer *buffer)
 743 {
 744         int idx;
 745         struct snd_card *card;
 746
 747         for (idx = 0; idx < SNDRV_CARDS; idx++) {
 748                 mutex_lock(&snd_card_mutex);
 749                 if ((card = snd_cards[idx]) != NULL)
 750                         snd_iprintf(buffer, "%2i %s\n",
 751                                     idx, card->module->name);
 752                 mutex_unlock(&snd_card_mutex);
 753         }
 754 }
 755 #endif
 756
 757 int __init snd_card_info_init(void)
 758 {
 759         struct snd_info_entry *entry;
 760
 761         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
 762         if (! entry)
 763                 return -ENOMEM;
 764         entry->c.text.read = snd_card_info_read;
 765         if (snd_info_register(entry) < 0) {
 766                 snd_info_free_entry(entry);
 767                 return -ENOMEM;
 768         }
 769         snd_card_info_entry = entry;
 770
 771 #ifdef MODULE
 772         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
 773         if (entry) {
 774                 entry->c.text.read = snd_card_module_info_read;
 775                 if (snd_info_register(entry) < 0)
 776                         snd_info_free_entry(entry);
 777                 else
 778                         snd_card_module_info_entry = entry;
 779         }
 780 #endif
 781
 782         return 0;
 783 }
 784
 785 int __exit snd_card_info_done(void)
 786 {
 787         snd_info_free_entry(snd_card_info_entry);
 788 #ifdef MODULE
 789         snd_info_free_entry(snd_card_module_info_entry);
 790 #endif
 791         return 0;
 792 }
 793
 794 #endif /* CONFIG_PROC_FS */
 795
 796 /**
 797  *  snd_component_add - add a component string
 798  *  @card: soundcard structure
 799  *  @component: the component id string
 800  *
 801  *  This function adds the component id string to the supported list.
 802  *  The component can be referred from the alsa-lib.
 803  *
 804  *  Returns zero otherwise a negative error code.
 805  */
 806
 807 int snd_component_add(struct snd_card *card, const char *component)
 808 {
 809         char *ptr;
 810         int len = strlen(component);
 811
 812         ptr = strstr(card->components, component);
 813         if (ptr != NULL) {
 814                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
 815                         return 1;
 816         }
 817         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
 818                 snd_BUG();
 819                 return -ENOMEM;
 820         }
 821         if (card->components[0] != '\0')
 822                 strcat(card->components, " ");
 823         strcat(card->components, component);
 824         return 0;
 825 }
 826
 827 EXPORT_SYMBOL(snd_component_add);
 828
 829 /**
 830  *  snd_card_file_add - add the file to the file list of the card
 831  *  @card: soundcard structure
 832  *  @file: file pointer
 833  *
 834  *  This function adds the file to the file linked-list of the card.
 835  *  This linked-list is used to keep tracking the connection state,
 836  *  and to avoid the release of busy resources by hotplug.
 837  *
 838  *  Returns zero or a negative error code.
 839  */
 840 int snd_card_file_add(struct snd_card *card, struct file *file)
 841 {
 842         struct snd_monitor_file *mfile;
 843
 844         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
 845         if (mfile == NULL)
 846                 return -ENOMEM;
 847         mfile->file = file;
 848         mfile->disconnected_f_op = NULL;
 849         INIT_LIST_HEAD(&mfile->shutdown_list);
 850         spin_lock(&card->files_lock);
 851         if (card->shutdown) {
 852                 spin_unlock(&card->files_lock);
 853                 kfree(mfile);
 854                 return -ENODEV;
 855         }
 856         list_add(&mfile->list, &card->files_list);
 857         spin_unlock(&card->files_lock);
 858         return 0;
 859 }
 860
 861 EXPORT_SYMBOL(snd_card_file_add);
 862
 863 /**
 864  *  snd_card_file_remove - remove the file from the file list
 865  *  @card: soundcard structure
 866  *  @file: file pointer
 867  *
 868  *  This function removes the file formerly added to the card via
 869  *  snd_card_file_add() function.
 870  *  If all files are removed and snd_card_free_when_closed() was
 871  *  called beforehand, it processes the pending release of
 872  *  resources.
 873  *
 874  *  Returns zero or a negative error code.
 875  */
 876 int snd_card_file_remove(struct snd_card *card, struct file *file)
 877 {
 878         struct snd_monitor_file *mfile, *found = NULL;
 879         int last_close = 0;
 880
 881         spin_lock(&card->files_lock);
 882         list_for_each_entry(mfile, &card->files_list, list) {
 883                 if (mfile->file == file) {
 884                         list_del(&mfile->list);
 885                         spin_lock(&shutdown_lock);
 886                         list_del(&mfile->shutdown_list);
 887                         spin_unlock(&shutdown_lock);
 888                         if (mfile->disconnected_f_op)
 889                                 fops_put(mfile->disconnected_f_op);
 890                         found = mfile;
 891                         break;
 892                 }
 893         }
 894         if (list_empty(&card->files_list))
 895                 last_close = 1;
 896         spin_unlock(&card->files_lock);
 897         if (last_close) {
 898                 wake_up(&card->shutdown_sleep);
 899                 if (card->free_on_last_close)
 900                         snd_card_do_free(card);
 901         }
 902         if (!found) {
 903                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
 904                 return -ENOENT;
 905         }
 906         kfree(found);
 907         return 0;
 908 }
 909
 910 EXPORT_SYMBOL(snd_card_file_remove);
 911
 912 #ifdef CONFIG_PM
 913 /**
 914  *  snd_power_wait - wait until the power-state is changed.
 915  *  @card: soundcard structure
 916  *  @power_state: expected power state
 917  *
 918  *  Waits until the power-state is changed.
 919  *
 920  *  Note: the power lock must be active before call.
 921  */
 922 int snd_power_wait(struct snd_card *card, unsigned int power_state)
 923 {
 924         wait_queue_t wait;
 925         int result = 0;
 926
 927         /* fastpath */
 928         if (snd_power_get_state(card) == power_state)
 929                 return 0;
 930         init_waitqueue_entry(&wait, current);
 931         add_wait_queue(&card->power_sleep, &wait);
 932         while (1) {
 933                 if (card->shutdown) {
 934                         result = -ENODEV;
 935                         break;
 936                 }
 937                 if (snd_power_get_state(card) == power_state)
 938                         break;
 939                 set_current_state(TASK_UNINTERRUPTIBLE);
 940                 snd_power_unlock(card);
 941                 schedule_timeout(30 * HZ);
 942                 snd_power_lock(card);
 943         }
 944         remove_wait_queue(&card->power_sleep, &wait);
 945         return result;
 946 }
 947
 948 EXPORT_SYMBOL(snd_power_wait);
 949 #endif /* CONFIG_PM */