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