init.c 21 KB

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