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