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_new - 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 * 130 * Creates and initializes a soundcard structure. 131 * 132 * Returns kmallocated snd_card structure. Creates the ALSA control interface 133 * (which is blocked until snd_card_register function is called). 134 */ 135 struct snd_card *snd_card_new(int idx, const char *xid, 136 struct module *module, int extra_size) 137 { 138 struct snd_card *card; 139 int err, idx2; 140 141 if (extra_size < 0) 142 extra_size = 0; 143 card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL); 144 if (card == NULL) 145 return NULL; 146 if (xid) { 147 if (!snd_info_check_reserved_words(xid)) 148 goto __error; 149 strlcpy(card->id, xid, sizeof(card->id)); 150 } 151 err = 0; 152 mutex_lock(&snd_card_mutex); 153 if (idx < 0) { 154 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) 155 /* idx == -1 == 0xffff means: take any free slot */ 156 if (~snd_cards_lock & idx & 1<<idx2) { 157 if (module_slot_match(module, idx2)) { 158 idx = idx2; 159 break; 160 } 161 } 162 } 163 if (idx < 0) { 164 for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) 165 /* idx == -1 == 0xffff means: take any free slot */ 166 if (~snd_cards_lock & idx & 1<<idx2) { 167 if (!slots[idx2] || !*slots[idx2]) { 168 idx = idx2; 169 break; 170 } 171 } 172 } 173 if (idx < 0) 174 err = -ENODEV; 175 else if (idx < snd_ecards_limit) { 176 if (snd_cards_lock & (1 << idx)) 177 err = -EBUSY; /* invalid */ 178 } else if (idx >= SNDRV_CARDS) 179 err = -ENODEV; 180 if (err < 0) { 181 mutex_unlock(&snd_card_mutex); 182 snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n", 183 idx, snd_ecards_limit - 1, err); 184 goto __error; 185 } 186 snd_cards_lock |= 1 << idx; /* lock it */ 187 if (idx >= snd_ecards_limit) 188 snd_ecards_limit = idx + 1; /* increase the limit */ 189 mutex_unlock(&snd_card_mutex); 190 card->number = idx; 191 card->module = module; 192 INIT_LIST_HEAD(&card->devices); 193 init_rwsem(&card->controls_rwsem); 194 rwlock_init(&card->ctl_files_rwlock); 195 INIT_LIST_HEAD(&card->controls); 196 INIT_LIST_HEAD(&card->ctl_files); 197 spin_lock_init(&card->files_lock); 198 init_waitqueue_head(&card->shutdown_sleep); 199 #ifdef CONFIG_PM 200 mutex_init(&card->power_lock); 201 init_waitqueue_head(&card->power_sleep); 202 #endif 203 /* the control interface cannot be accessed from the user space until */ 204 /* snd_cards_bitmask and snd_cards are set with snd_card_register */ 205 if ((err = snd_ctl_create(card)) < 0) { 206 snd_printd("unable to register control minors\n"); 207 goto __error; 208 } 209 if ((err = snd_info_card_create(card)) < 0) { 210 snd_printd("unable to create card info\n"); 211 goto __error_ctl; 212 } 213 if (extra_size > 0) 214 card->private_data = (char *)card + sizeof(struct snd_card); 215 return card; 216 217 __error_ctl: 218 snd_device_free_all(card, SNDRV_DEV_CMD_PRE); 219 __error: 220 kfree(card); 221 return NULL; 222 } 223 224 EXPORT_SYMBOL(snd_card_new); 225 226 /* return non-zero if a card is already locked */ 227 int snd_card_locked(int card) 228 { 229 int locked; 230 231 mutex_lock(&snd_card_mutex); 232 locked = snd_cards_lock & (1 << card); 233 mutex_unlock(&snd_card_mutex); 234 return locked; 235 } 236 237 static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig) 238 { 239 return -ENODEV; 240 } 241 242 static ssize_t snd_disconnect_read(struct file *file, char __user *buf, 243 size_t count, loff_t *offset) 244 { 245 return -ENODEV; 246 } 247 248 static ssize_t snd_disconnect_write(struct file *file, const char __user *buf, 249 size_t count, loff_t *offset) 250 { 251 return -ENODEV; 252 } 253 254 static int snd_disconnect_release(struct inode *inode, struct file *file) 255 { 256 struct snd_monitor_file *df = NULL, *_df; 257 258 spin_lock(&shutdown_lock); 259 list_for_each_entry(_df, &shutdown_files, shutdown_list) { 260 if (_df->file == file) { 261 df = _df; 262 break; 263 } 264 } 265 spin_unlock(&shutdown_lock); 266 267 if (likely(df)) 268 return df->disconnected_f_op->release(inode, file); 269 270 panic("%s(%p, %p) failed!", __func__, inode, file); 271 } 272 273 static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait) 274 { 275 return POLLERR | POLLNVAL; 276 } 277 278 static long snd_disconnect_ioctl(struct file *file, 279 unsigned int cmd, unsigned long arg) 280 { 281 return -ENODEV; 282 } 283 284 static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma) 285 { 286 return -ENODEV; 287 } 288 289 static int snd_disconnect_fasync(int fd, struct file *file, int on) 290 { 291 return -ENODEV; 292 } 293 294 static const struct file_operations snd_shutdown_f_ops = 295 { 296 .owner = THIS_MODULE, 297 .llseek = snd_disconnect_llseek, 298 .read = snd_disconnect_read, 299 .write = snd_disconnect_write, 300 .release = snd_disconnect_release, 301 .poll = snd_disconnect_poll, 302 .unlocked_ioctl = snd_disconnect_ioctl, 303 #ifdef CONFIG_COMPAT 304 .compat_ioctl = snd_disconnect_ioctl, 305 #endif 306 .mmap = snd_disconnect_mmap, 307 .fasync = snd_disconnect_fasync 308 }; 309 310 /** 311 * snd_card_disconnect - disconnect all APIs from the file-operations (user space) 312 * @card: soundcard structure 313 * 314 * Disconnects all APIs from the file-operations (user space). 315 * 316 * Returns zero, otherwise a negative error code. 317 * 318 * Note: The current implementation replaces all active file->f_op with special 319 * dummy file operations (they do nothing except release). 320 */ 321 int snd_card_disconnect(struct snd_card *card) 322 { 323 struct snd_monitor_file *mfile; 324 struct file *file; 325 int err; 326 327 if (!card) 328 return -EINVAL; 329 330 spin_lock(&card->files_lock); 331 if (card->shutdown) { 332 spin_unlock(&card->files_lock); 333 return 0; 334 } 335 card->shutdown = 1; 336 spin_unlock(&card->files_lock); 337 338 /* phase 1: disable fops (user space) operations for ALSA API */ 339 mutex_lock(&snd_card_mutex); 340 snd_cards[card->number] = NULL; 341 snd_cards_lock &= ~(1 << card->number); 342 mutex_unlock(&snd_card_mutex); 343 344 /* phase 2: replace file->f_op with special dummy operations */ 345 346 spin_lock(&card->files_lock); 347 mfile = card->files; 348 while (mfile) { 349 file = mfile->file; 350 351 /* it's critical part, use endless loop */ 352 /* we have no room to fail */ 353 mfile->disconnected_f_op = mfile->file->f_op; 354 355 spin_lock(&shutdown_lock); 356 list_add(&mfile->shutdown_list, &shutdown_files); 357 spin_unlock(&shutdown_lock); 358 359 mfile->file->f_op = &snd_shutdown_f_ops; 360 fops_get(mfile->file->f_op); 361 362 mfile = mfile->next; 363 } 364 spin_unlock(&card->files_lock); 365 366 /* phase 3: notify all connected devices about disconnection */ 367 /* at this point, they cannot respond to any calls except release() */ 368 369 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) 370 if (snd_mixer_oss_notify_callback) 371 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT); 372 #endif 373 374 /* notify all devices that we are disconnected */ 375 err = snd_device_disconnect_all(card); 376 if (err < 0) 377 snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number); 378 379 snd_info_card_disconnect(card); 380 #ifndef CONFIG_SYSFS_DEPRECATED 381 if (card->card_dev) { 382 device_unregister(card->card_dev); 383 card->card_dev = NULL; 384 } 385 #endif 386 #ifdef CONFIG_PM 387 wake_up(&card->power_sleep); 388 #endif 389 return 0; 390 } 391 392 EXPORT_SYMBOL(snd_card_disconnect); 393 394 /** 395 * snd_card_free - frees given soundcard structure 396 * @card: soundcard structure 397 * 398 * This function releases the soundcard structure and the all assigned 399 * devices automatically. That is, you don't have to release the devices 400 * by yourself. 401 * 402 * Returns zero. Frees all associated devices and frees the control 403 * interface associated to given soundcard. 404 */ 405 static int snd_card_do_free(struct snd_card *card) 406 { 407 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) 408 if (snd_mixer_oss_notify_callback) 409 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE); 410 #endif 411 if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) { 412 snd_printk(KERN_ERR "unable to free all devices (pre)\n"); 413 /* Fatal, but this situation should never occur */ 414 } 415 if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) { 416 snd_printk(KERN_ERR "unable to free all devices (normal)\n"); 417 /* Fatal, but this situation should never occur */ 418 } 419 if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) { 420 snd_printk(KERN_ERR "unable to free all devices (post)\n"); 421 /* Fatal, but this situation should never occur */ 422 } 423 if (card->private_free) 424 card->private_free(card); 425 snd_info_free_entry(card->proc_id); 426 if (snd_info_card_free(card) < 0) { 427 snd_printk(KERN_WARNING "unable to free card info\n"); 428 /* Not fatal error */ 429 } 430 kfree(card); 431 return 0; 432 } 433 434 int snd_card_free_when_closed(struct snd_card *card) 435 { 436 int free_now = 0; 437 int ret = snd_card_disconnect(card); 438 if (ret) 439 return ret; 440 441 spin_lock(&card->files_lock); 442 if (card->files == NULL) 443 free_now = 1; 444 else 445 card->free_on_last_close = 1; 446 spin_unlock(&card->files_lock); 447 448 if (free_now) 449 snd_card_do_free(card); 450 return 0; 451 } 452 453 EXPORT_SYMBOL(snd_card_free_when_closed); 454 455 int snd_card_free(struct snd_card *card) 456 { 457 int ret = snd_card_disconnect(card); 458 if (ret) 459 return ret; 460 461 /* wait, until all devices are ready for the free operation */ 462 wait_event(card->shutdown_sleep, card->files == NULL); 463 snd_card_do_free(card); 464 return 0; 465 } 466 467 EXPORT_SYMBOL(snd_card_free); 468 469 static void choose_default_id(struct snd_card *card) 470 { 471 int i, len, idx_flag = 0, loops = SNDRV_CARDS; 472 char *id, *spos; 473 474 id = spos = card->shortname; 475 while (*id != '\0') { 476 if (*id == ' ') 477 spos = id + 1; 478 id++; 479 } 480 id = card->id; 481 while (*spos != '\0' && !isalnum(*spos)) 482 spos++; 483 if (isdigit(*spos)) 484 *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D'; 485 while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) { 486 if (isalnum(*spos)) 487 *id++ = *spos; 488 spos++; 489 } 490 *id = '\0'; 491 492 id = card->id; 493 494 if (*id == '\0') 495 strcpy(id, "default"); 496 497 while (1) { 498 if (loops-- == 0) { 499 snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id); 500 strcpy(card->id, card->proc_root->name); 501 return; 502 } 503 if (!snd_info_check_reserved_words(id)) 504 goto __change; 505 for (i = 0; i < snd_ecards_limit; i++) { 506 if (snd_cards[i] && !strcmp(snd_cards[i]->id, id)) 507 goto __change; 508 } 509 break; 510 511 __change: 512 len = strlen(id); 513 if (idx_flag) { 514 if (id[len-1] != '9') 515 id[len-1]++; 516 else 517 id[len-1] = 'A'; 518 } else if ((size_t)len <= sizeof(card->id) - 3) { 519 strcat(id, "_1"); 520 idx_flag++; 521 } else { 522 spos = id + len - 2; 523 if ((size_t)len <= sizeof(card->id) - 2) 524 spos++; 525 *spos++ = '_'; 526 *spos++ = '1'; 527 *spos++ = '\0'; 528 idx_flag++; 529 } 530 } 531 } 532 533 /** 534 * snd_card_register - register the soundcard 535 * @card: soundcard structure 536 * 537 * This function registers all the devices assigned to the soundcard. 538 * Until calling this, the ALSA control interface is blocked from the 539 * external accesses. Thus, you should call this function at the end 540 * of the initialization of the card. 541 * 542 * Returns zero otherwise a negative error code if the registrain failed. 543 */ 544 int snd_card_register(struct snd_card *card) 545 { 546 int err; 547 548 snd_assert(card != NULL, return -EINVAL); 549 #ifndef CONFIG_SYSFS_DEPRECATED 550 if (!card->card_dev) { 551 card->card_dev = device_create_drvdata(sound_class, card->dev, 552 MKDEV(0, 0), NULL, 553 "card%i", card->number); 554 if (IS_ERR(card->card_dev)) 555 card->card_dev = NULL; 556 } 557 #endif 558 if ((err = snd_device_register_all(card)) < 0) 559 return err; 560 mutex_lock(&snd_card_mutex); 561 if (snd_cards[card->number]) { 562 /* already registered */ 563 mutex_unlock(&snd_card_mutex); 564 return 0; 565 } 566 if (card->id[0] == '\0') 567 choose_default_id(card); 568 snd_cards[card->number] = card; 569 mutex_unlock(&snd_card_mutex); 570 init_info_for_card(card); 571 #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) 572 if (snd_mixer_oss_notify_callback) 573 snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER); 574 #endif 575 return 0; 576 } 577 578 EXPORT_SYMBOL(snd_card_register); 579 580 #ifdef CONFIG_PROC_FS 581 static struct snd_info_entry *snd_card_info_entry; 582 583 static void snd_card_info_read(struct snd_info_entry *entry, 584 struct snd_info_buffer *buffer) 585 { 586 int idx, count; 587 struct snd_card *card; 588 589 for (idx = count = 0; idx < SNDRV_CARDS; idx++) { 590 mutex_lock(&snd_card_mutex); 591 if ((card = snd_cards[idx]) != NULL) { 592 count++; 593 snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n", 594 idx, 595 card->id, 596 card->driver, 597 card->shortname); 598 snd_iprintf(buffer, " %s\n", 599 card->longname); 600 } 601 mutex_unlock(&snd_card_mutex); 602 } 603 if (!count) 604 snd_iprintf(buffer, "--- no soundcards ---\n"); 605 } 606 607 #ifdef CONFIG_SND_OSSEMUL 608 609 void snd_card_info_read_oss(struct snd_info_buffer *buffer) 610 { 611 int idx, count; 612 struct snd_card *card; 613 614 for (idx = count = 0; idx < SNDRV_CARDS; idx++) { 615 mutex_lock(&snd_card_mutex); 616 if ((card = snd_cards[idx]) != NULL) { 617 count++; 618 snd_iprintf(buffer, "%s\n", card->longname); 619 } 620 mutex_unlock(&snd_card_mutex); 621 } 622 if (!count) { 623 snd_iprintf(buffer, "--- no soundcards ---\n"); 624 } 625 } 626 627 #endif 628 629 #ifdef MODULE 630 static struct snd_info_entry *snd_card_module_info_entry; 631 static void snd_card_module_info_read(struct snd_info_entry *entry, 632 struct snd_info_buffer *buffer) 633 { 634 int idx; 635 struct snd_card *card; 636 637 for (idx = 0; idx < SNDRV_CARDS; idx++) { 638 mutex_lock(&snd_card_mutex); 639 if ((card = snd_cards[idx]) != NULL) 640 snd_iprintf(buffer, "%2i %s\n", 641 idx, card->module->name); 642 mutex_unlock(&snd_card_mutex); 643 } 644 } 645 #endif 646 647 int __init snd_card_info_init(void) 648 { 649 struct snd_info_entry *entry; 650 651 entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL); 652 if (! entry) 653 return -ENOMEM; 654 entry->c.text.read = snd_card_info_read; 655 if (snd_info_register(entry) < 0) { 656 snd_info_free_entry(entry); 657 return -ENOMEM; 658 } 659 snd_card_info_entry = entry; 660 661 #ifdef MODULE 662 entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL); 663 if (entry) { 664 entry->c.text.read = snd_card_module_info_read; 665 if (snd_info_register(entry) < 0) 666 snd_info_free_entry(entry); 667 else 668 snd_card_module_info_entry = entry; 669 } 670 #endif 671 672 return 0; 673 } 674 675 int __exit snd_card_info_done(void) 676 { 677 snd_info_free_entry(snd_card_info_entry); 678 #ifdef MODULE 679 snd_info_free_entry(snd_card_module_info_entry); 680 #endif 681 return 0; 682 } 683 684 #endif /* CONFIG_PROC_FS */ 685 686 /** 687 * snd_component_add - add a component string 688 * @card: soundcard structure 689 * @component: the component id string 690 * 691 * This function adds the component id string to the supported list. 692 * The component can be referred from the alsa-lib. 693 * 694 * Returns zero otherwise a negative error code. 695 */ 696 697 int snd_component_add(struct snd_card *card, const char *component) 698 { 699 char *ptr; 700 int len = strlen(component); 701 702 ptr = strstr(card->components, component); 703 if (ptr != NULL) { 704 if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */ 705 return 1; 706 } 707 if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) { 708 snd_BUG(); 709 return -ENOMEM; 710 } 711 if (card->components[0] != '\0') 712 strcat(card->components, " "); 713 strcat(card->components, component); 714 return 0; 715 } 716 717 EXPORT_SYMBOL(snd_component_add); 718 719 /** 720 * snd_card_file_add - add the file to the file list of the card 721 * @card: soundcard structure 722 * @file: file pointer 723 * 724 * This function adds the file to the file linked-list of the card. 725 * This linked-list is used to keep tracking the connection state, 726 * and to avoid the release of busy resources by hotplug. 727 * 728 * Returns zero or a negative error code. 729 */ 730 int snd_card_file_add(struct snd_card *card, struct file *file) 731 { 732 struct snd_monitor_file *mfile; 733 734 mfile = kmalloc(sizeof(*mfile), GFP_KERNEL); 735 if (mfile == NULL) 736 return -ENOMEM; 737 mfile->file = file; 738 mfile->disconnected_f_op = NULL; 739 mfile->next = NULL; 740 spin_lock(&card->files_lock); 741 if (card->shutdown) { 742 spin_unlock(&card->files_lock); 743 kfree(mfile); 744 return -ENODEV; 745 } 746 mfile->next = card->files; 747 card->files = mfile; 748 spin_unlock(&card->files_lock); 749 return 0; 750 } 751 752 EXPORT_SYMBOL(snd_card_file_add); 753 754 /** 755 * snd_card_file_remove - remove the file from the file list 756 * @card: soundcard structure 757 * @file: file pointer 758 * 759 * This function removes the file formerly added to the card via 760 * snd_card_file_add() function. 761 * If all files are removed and snd_card_free_when_closed() was 762 * called beforehand, it processes the pending release of 763 * resources. 764 * 765 * Returns zero or a negative error code. 766 */ 767 int snd_card_file_remove(struct snd_card *card, struct file *file) 768 { 769 struct snd_monitor_file *mfile, *pfile = NULL; 770 int last_close = 0; 771 772 spin_lock(&card->files_lock); 773 mfile = card->files; 774 while (mfile) { 775 if (mfile->file == file) { 776 if (pfile) 777 pfile->next = mfile->next; 778 else 779 card->files = mfile->next; 780 break; 781 } 782 pfile = mfile; 783 mfile = mfile->next; 784 } 785 if (mfile && mfile->disconnected_f_op) { 786 fops_put(mfile->disconnected_f_op); 787 spin_lock(&shutdown_lock); 788 list_del(&mfile->shutdown_list); 789 spin_unlock(&shutdown_lock); 790 } 791 if (card->files == NULL) 792 last_close = 1; 793 spin_unlock(&card->files_lock); 794 if (last_close) { 795 wake_up(&card->shutdown_sleep); 796 if (card->free_on_last_close) 797 snd_card_do_free(card); 798 } 799 if (!mfile) { 800 snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file); 801 return -ENOENT; 802 } 803 kfree(mfile); 804 return 0; 805 } 806 807 EXPORT_SYMBOL(snd_card_file_remove); 808 809 #ifdef CONFIG_PM 810 /** 811 * snd_power_wait - wait until the power-state is changed. 812 * @card: soundcard structure 813 * @power_state: expected power state 814 * 815 * Waits until the power-state is changed. 816 * 817 * Note: the power lock must be active before call. 818 */ 819 int snd_power_wait(struct snd_card *card, unsigned int power_state) 820 { 821 wait_queue_t wait; 822 int result = 0; 823 824 /* fastpath */ 825 if (snd_power_get_state(card) == power_state) 826 return 0; 827 init_waitqueue_entry(&wait, current); 828 add_wait_queue(&card->power_sleep, &wait); 829 while (1) { 830 if (card->shutdown) { 831 result = -ENODEV; 832 break; 833 } 834 if (snd_power_get_state(card) == power_state) 835 break; 836 set_current_state(TASK_UNINTERRUPTIBLE); 837 snd_power_unlock(card); 838 schedule_timeout(30 * HZ); 839 snd_power_lock(card); 840 } 841 remove_wait_queue(&card->power_sleep, &wait); 842 return result; 843 } 844 845 EXPORT_SYMBOL(snd_power_wait); 846 #endif /* CONFIG_PM */ 847