git.oblomov.eu Git - linux-2.6/blob - sound/core/init.c

   1 /*
   2  *  Initialization routines
   3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   4  *
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #include <sound/driver.h>
  23 #include <linux/init.h>
  24 #include <linux/sched.h>
  25 #include <linux/file.h>
  26 #include <linux/slab.h>
  27 #include <linux/time.h>
  28 #include <linux/ctype.h>
  29 #include <linux/pci.h>
  30 #include <linux/pm.h>
  31 #include <sound/core.h>
  32 #include <sound/control.h>
  33 #include <sound/info.h>
  34
  35 struct snd_shutdown_f_ops {
  36         struct file_operations f_ops;
  37         struct snd_shutdown_f_ops *next;
  38 };
  39
  40 unsigned int snd_cards_lock = 0;        /* locked for registering/using */
  41 snd_card_t *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL};
  42 DEFINE_RWLOCK(snd_card_rwlock);
  43
  44 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
  45 int (*snd_mixer_oss_notify_callback)(snd_card_t *card, int free_flag);
  46 #endif
  47
  48 static void snd_card_id_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
  49 {
  50         snd_iprintf(buffer, "%s\n", entry->card->id);
  51 }
  52
  53 static void snd_card_free_thread(void * __card);
  54
  55 /**
  56  *  snd_card_new - create and initialize a soundcard structure
  57  *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
  58  *  @xid: card identification (ASCII string)
  59  *  @module: top level module for locking
  60  *  @extra_size: allocate this extra size after the main soundcard structure
  61  *
  62  *  Creates and initializes a soundcard structure.
  63  *
  64  *  Returns kmallocated snd_card_t structure. Creates the ALSA control interface
  65  *  (which is blocked until snd_card_register function is called).
  66  */
  67 snd_card_t *snd_card_new(int idx, const char *xid,
  68                          struct module *module, int extra_size)
  69 {
  70         snd_card_t *card;
  71         int err;
  72
  73         if (extra_size < 0)
  74                 extra_size = 0;
  75         card = kcalloc(1, sizeof(*card) + extra_size, GFP_KERNEL);
  76         if (card == NULL)
  77                 return NULL;
  78         if (xid) {
  79                 if (!snd_info_check_reserved_words(xid))
  80                         goto __error;
  81                 strlcpy(card->id, xid, sizeof(card->id));
  82         }
  83         err = 0;
  84         write_lock(&snd_card_rwlock);
  85         if (idx < 0) {
  86                 int idx2;
  87                 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
  88                         if (~snd_cards_lock & idx & 1<<idx2) {
  89                                 idx = idx2;
  90                                 if (idx >= snd_ecards_limit)
  91                                         snd_ecards_limit = idx + 1;
  92                                 break;
  93                         }
  94         } else if (idx < snd_ecards_limit) {
  95                 if (snd_cards_lock & (1 << idx))
  96                         err = -ENODEV;  /* invalid */
  97         } else if (idx < SNDRV_CARDS)
  98                 snd_ecards_limit = idx + 1; /* increase the limit */
  99         else
 100                 err = -ENODEV;
 101         if (idx < 0 || err < 0) {
 102                 write_unlock(&snd_card_rwlock);
 103                 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1);
 104                 goto __error;
 105         }
 106         snd_cards_lock |= 1 << idx;             /* lock it */
 107         write_unlock(&snd_card_rwlock);
 108         card->number = idx;
 109         card->module = module;
 110         INIT_LIST_HEAD(&card->devices);
 111         init_rwsem(&card->controls_rwsem);
 112         rwlock_init(&card->ctl_files_rwlock);
 113         INIT_LIST_HEAD(&card->controls);
 114         INIT_LIST_HEAD(&card->ctl_files);
 115         spin_lock_init(&card->files_lock);
 116         init_waitqueue_head(&card->shutdown_sleep);
 117         INIT_WORK(&card->free_workq, snd_card_free_thread, card);
 118 #ifdef CONFIG_PM
 119         init_MUTEX(&card->power_lock);
 120         init_waitqueue_head(&card->power_sleep);
 121 #endif
 122         /* the control interface cannot be accessed from the user space until */
 123         /* snd_cards_bitmask and snd_cards are set with snd_card_register */
 124         if ((err = snd_ctl_create(card)) < 0) {
 125                 snd_printd("unable to register control minors\n");
 126                 goto __error;
 127         }
 128         if ((err = snd_info_card_create(card)) < 0) {
 129                 snd_printd("unable to create card info\n");
 130                 goto __error_ctl;
 131         }
 132         if (extra_size > 0)
 133                 card->private_data = (char *)card + sizeof(snd_card_t);
 134         return card;
 135
 136       __error_ctl:
 137         snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
 138       __error:
 139         kfree(card);
 140         return NULL;
 141 }
 142
 143 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 144 {
 145         return POLLERR | POLLNVAL;
 146 }
 147
 148 /**
 149  *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 150  *  @card: soundcard structure
 151  *
 152  *  Disconnects all APIs from the file-operations (user space).
 153  *
 154  *  Returns zero, otherwise a negative error code.
 155  *
 156  *  Note: The current implementation replaces all active file->f_op with special
 157  *        dummy file operations (they do nothing except release).
 158  */
 159 int snd_card_disconnect(snd_card_t * card)
 160 {
 161         struct snd_monitor_file *mfile;
 162         struct file *file;
 163         struct snd_shutdown_f_ops *s_f_ops;
 164         struct file_operations *f_ops, *old_f_ops;
 165         int err;
 166
 167         spin_lock(&card->files_lock);
 168         if (card->shutdown) {
 169                 spin_unlock(&card->files_lock);
 170                 return 0;
 171         }
 172         card->shutdown = 1;
 173         spin_unlock(&card->files_lock);
 174
 175         /* phase 1: disable fops (user space) operations for ALSA API */
 176         write_lock(&snd_card_rwlock);
 177         snd_cards[card->number] = NULL;
 178         write_unlock(&snd_card_rwlock);
 179
 180         /* phase 2: replace file->f_op with special dummy operations */
 181
 182         spin_lock(&card->files_lock);
 183         mfile = card->files;
 184         while (mfile) {
 185                 file = mfile->file;
 186
 187                 /* it's critical part, use endless loop */
 188                 /* we have no room to fail */
 189                 s_f_ops = kmalloc(sizeof(struct snd_shutdown_f_ops), GFP_ATOMIC);
 190                 if (s_f_ops == NULL)
 191                         panic("Atomic allocation failed for snd_shutdown_f_ops!");
 192
 193                 f_ops = &s_f_ops->f_ops;
 194
 195                 memset(f_ops, 0, sizeof(*f_ops));
 196                 f_ops->owner = file->f_op->owner;
 197                 f_ops->release = file->f_op->release;
 198                 f_ops->poll = snd_disconnect_poll;
 199
 200                 s_f_ops->next = card->s_f_ops;
 201                 card->s_f_ops = s_f_ops;
 202
 203                 f_ops = fops_get(f_ops);
 204
 205                 old_f_ops = file->f_op;
 206                 file->f_op = f_ops;     /* must be atomic */
 207                 fops_put(old_f_ops);
 208
 209                 mfile = mfile->next;
 210         }
 211         spin_unlock(&card->files_lock);
 212
 213         /* phase 3: notify all connected devices about disconnection */
 214         /* at this point, they cannot respond to any calls except release() */
 215
 216 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 217         if (snd_mixer_oss_notify_callback)
 218                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
 219 #endif
 220
 221         /* notify all devices that we are disconnected */
 222         err = snd_device_disconnect_all(card);
 223         if (err < 0)
 224                 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
 225
 226         return 0;
 227 }
 228
 229 #if defined(CONFIG_PM) && defined(CONFIG_SND_GENERIC_PM)
 230 static void snd_generic_device_unregister(struct snd_generic_device *dev);
 231 #endif
 232
 233 /**
 234  *  snd_card_free - frees given soundcard structure
 235  *  @card: soundcard structure
 236  *
 237  *  This function releases the soundcard structure and the all assigned
 238  *  devices automatically.  That is, you don't have to release the devices
 239  *  by yourself.
 240  *
 241  *  Returns zero. Frees all associated devices and frees the control
 242  *  interface associated to given soundcard.
 243  */
 244 int snd_card_free(snd_card_t * card)
 245 {
 246         struct snd_shutdown_f_ops *s_f_ops;
 247
 248         if (card == NULL)
 249                 return -EINVAL;
 250         write_lock(&snd_card_rwlock);
 251         snd_cards[card->number] = NULL;
 252         write_unlock(&snd_card_rwlock);
 253
 254 #ifdef CONFIG_PM
 255         wake_up(&card->power_sleep);
 256 #ifdef CONFIG_SND_GENERIC_PM
 257         if (card->pm_dev) {
 258                 snd_generic_device_unregister(card->pm_dev);
 259                 card->pm_dev = NULL;
 260         }
 261 #endif
 262 #endif
 263
 264         /* wait, until all devices are ready for the free operation */
 265         wait_event(card->shutdown_sleep, card->files == NULL);
 266
 267 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 268         if (snd_mixer_oss_notify_callback)
 269                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
 270 #endif
 271         if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
 272                 snd_printk(KERN_ERR "unable to free all devices (pre)\n");
 273                 /* Fatal, but this situation should never occur */
 274         }
 275         if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
 276                 snd_printk(KERN_ERR "unable to free all devices (normal)\n");
 277                 /* Fatal, but this situation should never occur */
 278         }
 279         if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
 280                 snd_printk(KERN_ERR "unable to free all devices (post)\n");
 281                 /* Fatal, but this situation should never occur */
 282         }
 283         if (card->private_free)
 284                 card->private_free(card);
 285         if (card->proc_id)
 286                 snd_info_unregister(card->proc_id);
 287         if (snd_info_card_free(card) < 0) {
 288                 snd_printk(KERN_WARNING "unable to free card info\n");
 289                 /* Not fatal error */
 290         }
 291         while (card->s_f_ops) {
 292                 s_f_ops = card->s_f_ops;
 293                 card->s_f_ops = s_f_ops->next;
 294                 kfree(s_f_ops);
 295         }
 296         write_lock(&snd_card_rwlock);
 297         snd_cards_lock &= ~(1 << card->number);
 298         write_unlock(&snd_card_rwlock);
 299         kfree(card);
 300         return 0;
 301 }
 302
 303 static void snd_card_free_thread(void * __card)
 304 {
 305         snd_card_t *card = __card;
 306         struct module * module = card->module;
 307
 308         if (!try_module_get(module)) {
 309                 snd_printk(KERN_ERR "unable to lock toplevel module for card %i in free thread\n", card->number);
 310                 module = NULL;
 311         }
 312
 313         snd_card_free(card);
 314
 315         module_put(module);
 316 }
 317
 318 /**
 319  *  snd_card_free_in_thread - call snd_card_free() in thread
 320  *  @card: soundcard structure
 321  *
 322  *  This function schedules the call of snd_card_free() function in a
 323  *  work queue.  When all devices are released (non-busy), the work
 324  *  is woken up and calls snd_card_free().
 325  *
 326  *  When a card can be disconnected at any time by hotplug service,
 327  *  this function should be used in disconnect (or detach) callback
 328  *  instead of calling snd_card_free() directly.
 329  *
 330  *  Returns - zero otherwise a negative error code if the start of thread failed.
 331  */
 332 int snd_card_free_in_thread(snd_card_t * card)
 333 {
 334         if (card->files == NULL) {
 335                 snd_card_free(card);
 336                 return 0;
 337         }
 338
 339         if (schedule_work(&card->free_workq))
 340                 return 0;
 341
 342         snd_printk(KERN_ERR "schedule_work() failed in snd_card_free_in_thread for card %i\n", card->number);
 343         /* try to free the structure immediately */
 344         snd_card_free(card);
 345         return -EFAULT;
 346 }
 347
 348 static void choose_default_id(snd_card_t * card)
 349 {
 350         int i, len, idx_flag = 0, loops = 8;
 351         char *id, *spos;
 352
 353         id = spos = card->shortname;
 354         while (*id != '\0') {
 355                 if (*id == ' ')
 356                         spos = id + 1;
 357                 id++;
 358         }
 359         id = card->id;
 360         while (*spos != '\0' && !isalnum(*spos))
 361                 spos++;
 362         if (isdigit(*spos))
 363                 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
 364         while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
 365                 if (isalnum(*spos))
 366                         *id++ = *spos;
 367                 spos++;
 368         }
 369         *id = '\0';
 370
 371         id = card->id;
 372
 373         if (*id == '\0')
 374                 strcpy(id, "default");
 375
 376         while (1) {
 377                 if (loops-- == 0) {
 378                         snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
 379                         strcpy(card->id, card->proc_root->name);
 380                         return;
 381                 }
 382                 if (!snd_info_check_reserved_words(id))
 383                         goto __change;
 384                 for (i = 0; i < snd_ecards_limit; i++) {
 385                         if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
 386                                 goto __change;
 387                 }
 388                 break;
 389
 390               __change:
 391                 len = strlen(id);
 392                 if (idx_flag)
 393                         id[len-1]++;
 394                 else if ((size_t)len <= sizeof(card->id) - 3) {
 395                         strcat(id, "_1");
 396                         idx_flag++;
 397                 } else {
 398                         spos = id + len - 2;
 399                         if ((size_t)len <= sizeof(card->id) - 2)
 400                                 spos++;
 401                         *spos++ = '_';
 402                         *spos++ = '1';
 403                         *spos++ = '\0';
 404                         idx_flag++;
 405                 }
 406         }
 407 }
 408
 409 /**
 410  *  snd_card_register - register the soundcard
 411  *  @card: soundcard structure
 412  *
 413  *  This function registers all the devices assigned to the soundcard.
 414  *  Until calling this, the ALSA control interface is blocked from the
 415  *  external accesses.  Thus, you should call this function at the end
 416  *  of the initialization of the card.
 417  *
 418  *  Returns zero otherwise a negative error code if the registrain failed.
 419  */
 420 int snd_card_register(snd_card_t * card)
 421 {
 422         int err;
 423         snd_info_entry_t *entry;
 424
 425         snd_runtime_check(card != NULL, return -EINVAL);
 426         if ((err = snd_device_register_all(card)) < 0)
 427                 return err;
 428         write_lock(&snd_card_rwlock);
 429         if (snd_cards[card->number]) {
 430                 /* already registered */
 431                 write_unlock(&snd_card_rwlock);
 432                 return 0;
 433         }
 434         if (card->id[0] == '\0')
 435                 choose_default_id(card);
 436         snd_cards[card->number] = card;
 437         write_unlock(&snd_card_rwlock);
 438         if ((err = snd_info_card_register(card)) < 0) {
 439                 snd_printd("unable to create card info\n");
 440                 goto __skip_info;
 441         }
 442         if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
 443                 snd_printd("unable to create card entry\n");
 444                 goto __skip_info;
 445         }
 446         entry->c.text.read_size = PAGE_SIZE;
 447         entry->c.text.read = snd_card_id_read;
 448         if (snd_info_register(entry) < 0) {
 449                 snd_info_free_entry(entry);
 450                 entry = NULL;
 451         }
 452         card->proc_id = entry;
 453       __skip_info:
 454 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 455         if (snd_mixer_oss_notify_callback)
 456                 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
 457 #endif
 458         return 0;
 459 }
 460
 461 static snd_info_entry_t *snd_card_info_entry = NULL;
 462
 463 static void snd_card_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
 464 {
 465         int idx, count;
 466         snd_card_t *card;
 467
 468         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 469                 read_lock(&snd_card_rwlock);
 470                 if ((card = snd_cards[idx]) != NULL) {
 471                         count++;
 472                         snd_iprintf(buffer, "%i [%-15s]: %s - %s\n",
 473                                         idx,
 474                                         card->id,
 475                                         card->driver,
 476                                         card->shortname);
 477                         snd_iprintf(buffer, "                     %s\n",
 478                                         card->longname);
 479                 }
 480                 read_unlock(&snd_card_rwlock);
 481         }
 482         if (!count)
 483                 snd_iprintf(buffer, "--- no soundcards ---\n");
 484 }
 485
 486 #if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
 487
 488 void snd_card_info_read_oss(snd_info_buffer_t * buffer)
 489 {
 490         int idx, count;
 491         snd_card_t *card;
 492
 493         for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 494                 read_lock(&snd_card_rwlock);
 495                 if ((card = snd_cards[idx]) != NULL) {
 496                         count++;
 497                         snd_iprintf(buffer, "%s\n", card->longname);
 498                 }
 499                 read_unlock(&snd_card_rwlock);
 500         }
 501         if (!count) {
 502                 snd_iprintf(buffer, "--- no soundcards ---\n");
 503         }
 504 }
 505
 506 #endif
 507
 508 #ifdef MODULE
 509 static snd_info_entry_t *snd_card_module_info_entry;
 510 static void snd_card_module_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
 511 {
 512         int idx;
 513         snd_card_t *card;
 514
 515         for (idx = 0; idx < SNDRV_CARDS; idx++) {
 516                 read_lock(&snd_card_rwlock);
 517                 if ((card = snd_cards[idx]) != NULL)
 518                         snd_iprintf(buffer, "%i %s\n", idx, card->module->name);
 519                 read_unlock(&snd_card_rwlock);
 520         }
 521 }
 522 #endif
 523
 524 int __init snd_card_info_init(void)
 525 {
 526         snd_info_entry_t *entry;
 527
 528         entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
 529         snd_runtime_check(entry != NULL, return -ENOMEM);
 530         entry->c.text.read_size = PAGE_SIZE;
 531         entry->c.text.read = snd_card_info_read;
 532         if (snd_info_register(entry) < 0) {
 533                 snd_info_free_entry(entry);
 534                 return -ENOMEM;
 535         }
 536         snd_card_info_entry = entry;
 537
 538 #ifdef MODULE
 539         entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
 540         if (entry) {
 541                 entry->c.text.read_size = PAGE_SIZE;
 542                 entry->c.text.read = snd_card_module_info_read;
 543                 if (snd_info_register(entry) < 0)
 544                         snd_info_free_entry(entry);
 545                 else
 546                         snd_card_module_info_entry = entry;
 547         }
 548 #endif
 549
 550         return 0;
 551 }
 552
 553 int __exit snd_card_info_done(void)
 554 {
 555         if (snd_card_info_entry)
 556                 snd_info_unregister(snd_card_info_entry);
 557 #ifdef MODULE
 558         if (snd_card_module_info_entry)
 559                 snd_info_unregister(snd_card_module_info_entry);
 560 #endif
 561         return 0;
 562 }
 563
 564 /**
 565  *  snd_component_add - add a component string
 566  *  @card: soundcard structure
 567  *  @component: the component id string
 568  *
 569  *  This function adds the component id string to the supported list.
 570  *  The component can be referred from the alsa-lib.
 571  *
 572  *  Returns zero otherwise a negative error code.
 573  */
 574
 575 int snd_component_add(snd_card_t *card, const char *component)
 576 {
 577         char *ptr;
 578         int len = strlen(component);
 579
 580         ptr = strstr(card->components, component);
 581         if (ptr != NULL) {
 582                 if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
 583                         return 1;
 584         }
 585         if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
 586                 snd_BUG();
 587                 return -ENOMEM;
 588         }
 589         if (card->components[0] != '\0')
 590                 strcat(card->components, " ");
 591         strcat(card->components, component);
 592         return 0;
 593 }
 594
 595 /**
 596  *  snd_card_file_add - add the file to the file list of the card
 597  *  @card: soundcard structure
 598  *  @file: file pointer
 599  *
 600  *  This function adds the file to the file linked-list of the card.
 601  *  This linked-list is used to keep tracking the connection state,
 602  *  and to avoid the release of busy resources by hotplug.
 603  *
 604  *  Returns zero or a negative error code.
 605  */
 606 int snd_card_file_add(snd_card_t *card, struct file *file)
 607 {
 608         struct snd_monitor_file *mfile;
 609
 610         mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
 611         if (mfile == NULL)
 612                 return -ENOMEM;
 613         mfile->file = file;
 614         mfile->next = NULL;
 615         spin_lock(&card->files_lock);
 616         if (card->shutdown) {
 617                 spin_unlock(&card->files_lock);
 618                 kfree(mfile);
 619                 return -ENODEV;
 620         }
 621         mfile->next = card->files;
 622         card->files = mfile;
 623         spin_unlock(&card->files_lock);
 624         return 0;
 625 }
 626
 627 /**
 628  *  snd_card_file_remove - remove the file from the file list
 629  *  @card: soundcard structure
 630  *  @file: file pointer
 631  *
 632  *  This function removes the file formerly added to the card via
 633  *  snd_card_file_add() function.
 634  *  If all files are removed and the release of the card is
 635  *  scheduled, it will wake up the the thread to call snd_card_free()
 636  *  (see snd_card_free_in_thread() function).
 637  *
 638  *  Returns zero or a negative error code.
 639  */
 640 int snd_card_file_remove(snd_card_t *card, struct file *file)
 641 {
 642         struct snd_monitor_file *mfile, *pfile = NULL;
 643
 644         spin_lock(&card->files_lock);
 645         mfile = card->files;
 646         while (mfile) {
 647                 if (mfile->file == file) {
 648                         if (pfile)
 649                                 pfile->next = mfile->next;
 650                         else
 651                                 card->files = mfile->next;
 652                         break;
 653                 }
 654                 pfile = mfile;
 655                 mfile = mfile->next;
 656         }
 657         spin_unlock(&card->files_lock);
 658         if (card->files == NULL)
 659                 wake_up(&card->shutdown_sleep);
 660         if (!mfile) {
 661                 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
 662                 return -ENOENT;
 663         }
 664         kfree(mfile);
 665         return 0;
 666 }
 667
 668 #ifdef CONFIG_PM
 669 /**
 670  *  snd_power_wait - wait until the power-state is changed.
 671  *  @card: soundcard structure
 672  *  @power_state: expected power state
 673  *  @file: file structure for the O_NONBLOCK check (optional)
 674  *
 675  *  Waits until the power-state is changed.
 676  *
 677  *  Note: the power lock must be active before call.
 678  */
 679 int snd_power_wait(snd_card_t *card, unsigned int power_state, struct file *file)
 680 {
 681         wait_queue_t wait;
 682         int result = 0;
 683
 684         /* fastpath */
 685         if (snd_power_get_state(card) == power_state)
 686                 return 0;
 687         init_waitqueue_entry(&wait, current);
 688         add_wait_queue(&card->power_sleep, &wait);
 689         while (1) {
 690                 if (card->shutdown) {
 691                         result = -ENODEV;
 692                         break;
 693                 }
 694                 if (snd_power_get_state(card) == power_state)
 695                         break;
 696 #if 0 /* block all devices */
 697                 if (file && (file->f_flags & O_NONBLOCK)) {
 698                         result = -EAGAIN;
 699                         break;
 700                 }
 701 #endif
 702                 set_current_state(TASK_UNINTERRUPTIBLE);
 703                 snd_power_unlock(card);
 704                 schedule_timeout(30 * HZ);
 705                 snd_power_lock(card);
 706         }
 707         remove_wait_queue(&card->power_sleep, &wait);
 708         return result;
 709 }
 710
 711 /**
 712  * snd_card_set_pm_callback - set the PCI power-management callbacks
 713  * @card: soundcard structure
 714  * @suspend: suspend callback function
 715  * @resume: resume callback function
 716  * @private_data: private data to pass to the callback functions
 717  *
 718  * Sets the power-management callback functions of the card.
 719  * These callbacks are called from ALSA's common PCI suspend/resume
 720  * handler and from the control API.
 721  */
 722 int snd_card_set_pm_callback(snd_card_t *card,
 723                              int (*suspend)(snd_card_t *, pm_message_t),
 724                              int (*resume)(snd_card_t *),
 725                              void *private_data)
 726 {
 727         card->pm_suspend = suspend;
 728         card->pm_resume = resume;
 729         card->pm_private_data = private_data;
 730         return 0;
 731 }
 732
 733 #ifdef CONFIG_SND_GENERIC_PM
 734 /*
 735  * use platform_device for generic power-management without a proper bus
 736  * (e.g. ISA)
 737  */
 738 struct snd_generic_device {
 739         struct platform_device pdev;
 740         snd_card_t *card;
 741 };
 742
 743 #define get_snd_generic_card(dev)       container_of(to_platform_device(dev), struct snd_generic_device, pdev)->card
 744
 745 #define SND_GENERIC_NAME        "snd_generic_pm"
 746
 747 static int snd_generic_suspend(struct device *dev, pm_message_t state, u32 level);
 748 static int snd_generic_resume(struct device *dev, u32 level);
 749
 750 static struct device_driver snd_generic_driver = {
 751         .name           = SND_GENERIC_NAME,
 752         .bus            = &platform_bus_type,
 753         .suspend        = snd_generic_suspend,
 754         .resume         = snd_generic_resume,
 755 };
 756
 757 static int generic_driver_registered;
 758
 759 static void generic_driver_unregister(void)
 760 {
 761         if (generic_driver_registered) {
 762                 generic_driver_registered--;
 763                 if (! generic_driver_registered)
 764                         driver_unregister(&snd_generic_driver);
 765         }
 766 }
 767
 768 static struct snd_generic_device *snd_generic_device_register(snd_card_t *card)
 769 {
 770         struct snd_generic_device *dev;
 771
 772         if (! generic_driver_registered) {
 773                 if (driver_register(&snd_generic_driver) < 0)
 774                         return NULL;
 775         }
 776         generic_driver_registered++;
 777
 778         dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
 779         if (! dev) {
 780                 generic_driver_unregister();
 781                 return NULL;
 782         }
 783
 784         dev->pdev.name = SND_GENERIC_NAME;
 785         dev->pdev.id = card->number;
 786         dev->card = card;
 787         if (platform_device_register(&dev->pdev) < 0) {
 788                 kfree(dev);
 789                 generic_driver_unregister();
 790                 return NULL;
 791         }
 792         return dev;
 793 }
 794
 795 static void snd_generic_device_unregister(struct snd_generic_device *dev)
 796 {
 797         platform_device_unregister(&dev->pdev);
 798         kfree(dev);
 799         generic_driver_unregister();
 800 }
 801
 802 /* suspend/resume callbacks for snd_generic platform device */
 803 static int snd_generic_suspend(struct device *dev, pm_message_t state, u32 level)
 804 {
 805         snd_card_t *card;
 806
 807         if (level != SUSPEND_DISABLE)
 808                 return 0;
 809
 810         card = get_snd_generic_card(dev);
 811         if (card->power_state == SNDRV_CTL_POWER_D3hot)
 812                 return 0;
 813         card->pm_suspend(card, PMSG_SUSPEND);
 814         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 815         return 0;
 816 }
 817
 818 static int snd_generic_resume(struct device *dev, u32 level)
 819 {
 820         snd_card_t *card;
 821
 822         if (level != RESUME_ENABLE)
 823                 return 0;
 824
 825         card = get_snd_generic_card(dev);
 826         if (card->power_state == SNDRV_CTL_POWER_D0)
 827                 return 0;
 828         card->pm_resume(card);
 829         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 830         return 0;
 831 }
 832
 833 /**
 834  * snd_card_set_generic_pm_callback - set the generic power-management callbacks
 835  * @card: soundcard structure
 836  * @suspend: suspend callback function
 837  * @resume: resume callback function
 838  * @private_data: private data to pass to the callback functions
 839  *
 840  * Registers the power-management and sets the lowlevel callbacks for
 841  * the given card.  These callbacks are called from the ALSA's common
 842  * PM handler and from the control API.
 843  */
 844 int snd_card_set_generic_pm_callback(snd_card_t *card,
 845                                  int (*suspend)(snd_card_t *, pm_message_t),
 846                                  int (*resume)(snd_card_t *),
 847                                  void *private_data)
 848 {
 849         card->pm_dev = snd_generic_device_register(card);
 850         if (! card->pm_dev)
 851                 return -ENOMEM;
 852         snd_card_set_pm_callback(card, suspend, resume, private_data);
 853         return 0;
 854 }
 855 #endif /* CONFIG_SND_GENERIC_PM */
 856
 857 #ifdef CONFIG_PCI
 858 int snd_card_pci_suspend(struct pci_dev *dev, pm_message_t state)
 859 {
 860         snd_card_t *card = pci_get_drvdata(dev);
 861         int err;
 862         if (! card || ! card->pm_suspend)
 863                 return 0;
 864         if (card->power_state == SNDRV_CTL_POWER_D3hot)
 865                 return 0;
 866         err = card->pm_suspend(card, PMSG_SUSPEND);
 867         pci_save_state(dev);
 868         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 869         return err;
 870 }
 871
 872 int snd_card_pci_resume(struct pci_dev *dev)
 873 {
 874         snd_card_t *card = pci_get_drvdata(dev);
 875         if (! card || ! card->pm_resume)
 876                 return 0;
 877         if (card->power_state == SNDRV_CTL_POWER_D0)
 878                 return 0;
 879         /* restore the PCI config space */
 880         pci_restore_state(dev);
 881         card->pm_resume(card);
 882         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 883         return 0;
 884 }
 885 #endif
 886
 887 #endif /* CONFIG_PM */