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