chip.c 20 KB

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  1. /*
  2. * linux/kernel/irq/chip.c
  3. *
  4. * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
  5. * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
  6. *
  7. * This file contains the core interrupt handling code, for irq-chip
  8. * based architectures.
  9. *
  10. * Detailed information is available in Documentation/DocBook/genericirq
  11. */
  12. #include <linux/irq.h>
  13. #include <linux/msi.h>
  14. #include <linux/module.h>
  15. #include <linux/interrupt.h>
  16. #include <linux/kernel_stat.h>
  17. #include "internals.h"
  18. static void dynamic_irq_init_x(unsigned int irq, bool keep_chip_data)
  19. {
  20. struct irq_desc *desc;
  21. unsigned long flags;
  22. desc = irq_to_desc(irq);
  23. if (!desc) {
  24. WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
  25. return;
  26. }
  27. /* Ensure we don't have left over values from a previous use of this irq */
  28. raw_spin_lock_irqsave(&desc->lock, flags);
  29. desc->status = IRQ_DISABLED;
  30. desc->irq_data.chip = &no_irq_chip;
  31. desc->handle_irq = handle_bad_irq;
  32. desc->depth = 1;
  33. desc->irq_data.msi_desc = NULL;
  34. desc->irq_data.handler_data = NULL;
  35. if (!keep_chip_data)
  36. desc->irq_data.chip_data = NULL;
  37. desc->action = NULL;
  38. desc->irq_count = 0;
  39. desc->irqs_unhandled = 0;
  40. #ifdef CONFIG_SMP
  41. cpumask_setall(desc->irq_data.affinity);
  42. #ifdef CONFIG_GENERIC_PENDING_IRQ
  43. cpumask_clear(desc->pending_mask);
  44. #endif
  45. #endif
  46. raw_spin_unlock_irqrestore(&desc->lock, flags);
  47. }
  48. /**
  49. * dynamic_irq_init - initialize a dynamically allocated irq
  50. * @irq: irq number to initialize
  51. */
  52. void dynamic_irq_init(unsigned int irq)
  53. {
  54. dynamic_irq_init_x(irq, false);
  55. }
  56. /**
  57. * dynamic_irq_init_keep_chip_data - initialize a dynamically allocated irq
  58. * @irq: irq number to initialize
  59. *
  60. * does not set irq_to_desc(irq)->irq_data.chip_data to NULL
  61. */
  62. void dynamic_irq_init_keep_chip_data(unsigned int irq)
  63. {
  64. dynamic_irq_init_x(irq, true);
  65. }
  66. static void dynamic_irq_cleanup_x(unsigned int irq, bool keep_chip_data)
  67. {
  68. struct irq_desc *desc = irq_to_desc(irq);
  69. unsigned long flags;
  70. if (!desc) {
  71. WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
  72. return;
  73. }
  74. raw_spin_lock_irqsave(&desc->lock, flags);
  75. if (desc->action) {
  76. raw_spin_unlock_irqrestore(&desc->lock, flags);
  77. WARN(1, KERN_ERR "Destroying IRQ%d without calling free_irq\n",
  78. irq);
  79. return;
  80. }
  81. desc->irq_data.msi_desc = NULL;
  82. desc->irq_data.handler_data = NULL;
  83. if (!keep_chip_data)
  84. desc->irq_data.chip_data = NULL;
  85. desc->handle_irq = handle_bad_irq;
  86. desc->irq_data.chip = &no_irq_chip;
  87. desc->name = NULL;
  88. clear_kstat_irqs(desc);
  89. raw_spin_unlock_irqrestore(&desc->lock, flags);
  90. }
  91. /**
  92. * dynamic_irq_cleanup - cleanup a dynamically allocated irq
  93. * @irq: irq number to initialize
  94. */
  95. void dynamic_irq_cleanup(unsigned int irq)
  96. {
  97. dynamic_irq_cleanup_x(irq, false);
  98. }
  99. /**
  100. * dynamic_irq_cleanup_keep_chip_data - cleanup a dynamically allocated irq
  101. * @irq: irq number to initialize
  102. *
  103. * does not set irq_to_desc(irq)->irq_data.chip_data to NULL
  104. */
  105. void dynamic_irq_cleanup_keep_chip_data(unsigned int irq)
  106. {
  107. dynamic_irq_cleanup_x(irq, true);
  108. }
  109. /**
  110. * set_irq_chip - set the irq chip for an irq
  111. * @irq: irq number
  112. * @chip: pointer to irq chip description structure
  113. */
  114. int set_irq_chip(unsigned int irq, struct irq_chip *chip)
  115. {
  116. struct irq_desc *desc = irq_to_desc(irq);
  117. unsigned long flags;
  118. if (!desc) {
  119. WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
  120. return -EINVAL;
  121. }
  122. if (!chip)
  123. chip = &no_irq_chip;
  124. raw_spin_lock_irqsave(&desc->lock, flags);
  125. irq_chip_set_defaults(chip);
  126. desc->irq_data.chip = chip;
  127. raw_spin_unlock_irqrestore(&desc->lock, flags);
  128. return 0;
  129. }
  130. EXPORT_SYMBOL(set_irq_chip);
  131. /**
  132. * set_irq_type - set the irq trigger type for an irq
  133. * @irq: irq number
  134. * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
  135. */
  136. int set_irq_type(unsigned int irq, unsigned int type)
  137. {
  138. struct irq_desc *desc = irq_to_desc(irq);
  139. unsigned long flags;
  140. int ret = -ENXIO;
  141. if (!desc) {
  142. printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
  143. return -ENODEV;
  144. }
  145. type &= IRQ_TYPE_SENSE_MASK;
  146. if (type == IRQ_TYPE_NONE)
  147. return 0;
  148. raw_spin_lock_irqsave(&desc->lock, flags);
  149. ret = __irq_set_trigger(desc, irq, type);
  150. raw_spin_unlock_irqrestore(&desc->lock, flags);
  151. return ret;
  152. }
  153. EXPORT_SYMBOL(set_irq_type);
  154. /**
  155. * set_irq_data - set irq type data for an irq
  156. * @irq: Interrupt number
  157. * @data: Pointer to interrupt specific data
  158. *
  159. * Set the hardware irq controller data for an irq
  160. */
  161. int set_irq_data(unsigned int irq, void *data)
  162. {
  163. struct irq_desc *desc = irq_to_desc(irq);
  164. unsigned long flags;
  165. if (!desc) {
  166. printk(KERN_ERR
  167. "Trying to install controller data for IRQ%d\n", irq);
  168. return -EINVAL;
  169. }
  170. raw_spin_lock_irqsave(&desc->lock, flags);
  171. desc->irq_data.handler_data = data;
  172. raw_spin_unlock_irqrestore(&desc->lock, flags);
  173. return 0;
  174. }
  175. EXPORT_SYMBOL(set_irq_data);
  176. /**
  177. * set_irq_msi - set MSI descriptor data for an irq
  178. * @irq: Interrupt number
  179. * @entry: Pointer to MSI descriptor data
  180. *
  181. * Set the MSI descriptor entry for an irq
  182. */
  183. int set_irq_msi(unsigned int irq, struct msi_desc *entry)
  184. {
  185. struct irq_desc *desc = irq_to_desc(irq);
  186. unsigned long flags;
  187. if (!desc) {
  188. printk(KERN_ERR
  189. "Trying to install msi data for IRQ%d\n", irq);
  190. return -EINVAL;
  191. }
  192. raw_spin_lock_irqsave(&desc->lock, flags);
  193. desc->irq_data.msi_desc = entry;
  194. if (entry)
  195. entry->irq = irq;
  196. raw_spin_unlock_irqrestore(&desc->lock, flags);
  197. return 0;
  198. }
  199. /**
  200. * set_irq_chip_data - set irq chip data for an irq
  201. * @irq: Interrupt number
  202. * @data: Pointer to chip specific data
  203. *
  204. * Set the hardware irq chip data for an irq
  205. */
  206. int set_irq_chip_data(unsigned int irq, void *data)
  207. {
  208. struct irq_desc *desc = irq_to_desc(irq);
  209. unsigned long flags;
  210. if (!desc) {
  211. printk(KERN_ERR
  212. "Trying to install chip data for IRQ%d\n", irq);
  213. return -EINVAL;
  214. }
  215. if (!desc->irq_data.chip) {
  216. printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
  217. return -EINVAL;
  218. }
  219. raw_spin_lock_irqsave(&desc->lock, flags);
  220. desc->irq_data.chip_data = data;
  221. raw_spin_unlock_irqrestore(&desc->lock, flags);
  222. return 0;
  223. }
  224. EXPORT_SYMBOL(set_irq_chip_data);
  225. /**
  226. * set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
  227. *
  228. * @irq: Interrupt number
  229. * @nest: 0 to clear / 1 to set the IRQ_NESTED_THREAD flag
  230. *
  231. * The IRQ_NESTED_THREAD flag indicates that on
  232. * request_threaded_irq() no separate interrupt thread should be
  233. * created for the irq as the handler are called nested in the
  234. * context of a demultiplexing interrupt handler thread.
  235. */
  236. void set_irq_nested_thread(unsigned int irq, int nest)
  237. {
  238. struct irq_desc *desc = irq_to_desc(irq);
  239. unsigned long flags;
  240. if (!desc)
  241. return;
  242. raw_spin_lock_irqsave(&desc->lock, flags);
  243. if (nest)
  244. desc->status |= IRQ_NESTED_THREAD;
  245. else
  246. desc->status &= ~IRQ_NESTED_THREAD;
  247. raw_spin_unlock_irqrestore(&desc->lock, flags);
  248. }
  249. EXPORT_SYMBOL_GPL(set_irq_nested_thread);
  250. /*
  251. * default enable function
  252. */
  253. static void default_enable(struct irq_data *data)
  254. {
  255. struct irq_desc *desc = irq_data_to_desc(data);
  256. desc->irq_data.chip->irq_unmask(&desc->irq_data);
  257. desc->status &= ~IRQ_MASKED;
  258. }
  259. /*
  260. * default disable function
  261. */
  262. static void default_disable(struct irq_data *data)
  263. {
  264. }
  265. /*
  266. * default startup function
  267. */
  268. static unsigned int default_startup(struct irq_data *data)
  269. {
  270. struct irq_desc *desc = irq_data_to_desc(data);
  271. desc->irq_data.chip->irq_enable(data);
  272. return 0;
  273. }
  274. /*
  275. * default shutdown function
  276. */
  277. static void default_shutdown(struct irq_data *data)
  278. {
  279. struct irq_desc *desc = irq_data_to_desc(data);
  280. desc->irq_data.chip->irq_mask(&desc->irq_data);
  281. desc->status |= IRQ_MASKED;
  282. }
  283. /* Temporary migration helpers */
  284. static void compat_irq_mask(struct irq_data *data)
  285. {
  286. data->chip->mask(data->irq);
  287. }
  288. static void compat_irq_unmask(struct irq_data *data)
  289. {
  290. data->chip->unmask(data->irq);
  291. }
  292. static void compat_irq_ack(struct irq_data *data)
  293. {
  294. data->chip->ack(data->irq);
  295. }
  296. static void compat_irq_mask_ack(struct irq_data *data)
  297. {
  298. data->chip->mask_ack(data->irq);
  299. }
  300. static void compat_irq_eoi(struct irq_data *data)
  301. {
  302. data->chip->eoi(data->irq);
  303. }
  304. static void compat_irq_enable(struct irq_data *data)
  305. {
  306. data->chip->enable(data->irq);
  307. }
  308. static void compat_irq_disable(struct irq_data *data)
  309. {
  310. data->chip->disable(data->irq);
  311. }
  312. static void compat_irq_shutdown(struct irq_data *data)
  313. {
  314. data->chip->shutdown(data->irq);
  315. }
  316. static unsigned int compat_irq_startup(struct irq_data *data)
  317. {
  318. return data->chip->startup(data->irq);
  319. }
  320. static void compat_bus_lock(struct irq_data *data)
  321. {
  322. data->chip->bus_lock(data->irq);
  323. }
  324. static void compat_bus_sync_unlock(struct irq_data *data)
  325. {
  326. data->chip->bus_sync_unlock(data->irq);
  327. }
  328. /*
  329. * Fixup enable/disable function pointers
  330. */
  331. void irq_chip_set_defaults(struct irq_chip *chip)
  332. {
  333. /*
  334. * Compat fixup functions need to be before we set the
  335. * defaults for enable/disable/startup/shutdown
  336. */
  337. if (chip->enable)
  338. chip->irq_enable = compat_irq_enable;
  339. if (chip->disable)
  340. chip->irq_disable = compat_irq_disable;
  341. if (chip->shutdown)
  342. chip->irq_shutdown = compat_irq_shutdown;
  343. if (chip->startup)
  344. chip->irq_startup = compat_irq_startup;
  345. /*
  346. * The real defaults
  347. */
  348. if (!chip->irq_enable)
  349. chip->irq_enable = default_enable;
  350. if (!chip->irq_disable)
  351. chip->irq_disable = default_disable;
  352. if (!chip->irq_startup)
  353. chip->irq_startup = default_startup;
  354. /*
  355. * We use chip->irq_disable, when the user provided its own. When
  356. * we have default_disable set for chip->irq_disable, then we need
  357. * to use default_shutdown, otherwise the irq line is not
  358. * disabled on free_irq():
  359. */
  360. if (!chip->irq_shutdown)
  361. chip->irq_shutdown = chip->irq_disable != default_disable ?
  362. chip->irq_disable : default_shutdown;
  363. if (!chip->end)
  364. chip->end = dummy_irq_chip.end;
  365. /*
  366. * Now fix up the remaining compat handlers
  367. */
  368. if (chip->bus_lock)
  369. chip->irq_bus_lock = compat_bus_lock;
  370. if (chip->bus_sync_unlock)
  371. chip->irq_bus_sync_unlock = compat_bus_sync_unlock;
  372. if (chip->mask)
  373. chip->irq_mask = compat_irq_mask;
  374. if (chip->unmask)
  375. chip->irq_unmask = compat_irq_unmask;
  376. if (chip->ack)
  377. chip->irq_ack = compat_irq_ack;
  378. if (chip->mask_ack)
  379. chip->irq_mask_ack = compat_irq_mask_ack;
  380. if (chip->eoi)
  381. chip->irq_eoi = compat_irq_eoi;
  382. }
  383. static inline void mask_ack_irq(struct irq_desc *desc)
  384. {
  385. if (desc->irq_data.chip->irq_mask_ack)
  386. desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
  387. else {
  388. desc->irq_data.chip->irq_mask(&desc->irq_data);
  389. if (desc->irq_data.chip->irq_ack)
  390. desc->irq_data.chip->irq_ack(&desc->irq_data);
  391. }
  392. desc->status |= IRQ_MASKED;
  393. }
  394. static inline void mask_irq(struct irq_desc *desc)
  395. {
  396. if (desc->irq_data.chip->irq_mask) {
  397. desc->irq_data.chip->irq_mask(&desc->irq_data);
  398. desc->status |= IRQ_MASKED;
  399. }
  400. }
  401. static inline void unmask_irq(struct irq_desc *desc)
  402. {
  403. if (desc->irq_data.chip->irq_unmask) {
  404. desc->irq_data.chip->irq_unmask(&desc->irq_data);
  405. desc->status &= ~IRQ_MASKED;
  406. }
  407. }
  408. /*
  409. * handle_nested_irq - Handle a nested irq from a irq thread
  410. * @irq: the interrupt number
  411. *
  412. * Handle interrupts which are nested into a threaded interrupt
  413. * handler. The handler function is called inside the calling
  414. * threads context.
  415. */
  416. void handle_nested_irq(unsigned int irq)
  417. {
  418. struct irq_desc *desc = irq_to_desc(irq);
  419. struct irqaction *action;
  420. irqreturn_t action_ret;
  421. might_sleep();
  422. raw_spin_lock_irq(&desc->lock);
  423. kstat_incr_irqs_this_cpu(irq, desc);
  424. action = desc->action;
  425. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  426. goto out_unlock;
  427. desc->status |= IRQ_INPROGRESS;
  428. raw_spin_unlock_irq(&desc->lock);
  429. action_ret = action->thread_fn(action->irq, action->dev_id);
  430. if (!noirqdebug)
  431. note_interrupt(irq, desc, action_ret);
  432. raw_spin_lock_irq(&desc->lock);
  433. desc->status &= ~IRQ_INPROGRESS;
  434. out_unlock:
  435. raw_spin_unlock_irq(&desc->lock);
  436. }
  437. EXPORT_SYMBOL_GPL(handle_nested_irq);
  438. /**
  439. * handle_simple_irq - Simple and software-decoded IRQs.
  440. * @irq: the interrupt number
  441. * @desc: the interrupt description structure for this irq
  442. *
  443. * Simple interrupts are either sent from a demultiplexing interrupt
  444. * handler or come from hardware, where no interrupt hardware control
  445. * is necessary.
  446. *
  447. * Note: The caller is expected to handle the ack, clear, mask and
  448. * unmask issues if necessary.
  449. */
  450. void
  451. handle_simple_irq(unsigned int irq, struct irq_desc *desc)
  452. {
  453. struct irqaction *action;
  454. irqreturn_t action_ret;
  455. raw_spin_lock(&desc->lock);
  456. if (unlikely(desc->status & IRQ_INPROGRESS))
  457. goto out_unlock;
  458. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  459. kstat_incr_irqs_this_cpu(irq, desc);
  460. action = desc->action;
  461. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  462. goto out_unlock;
  463. desc->status |= IRQ_INPROGRESS;
  464. raw_spin_unlock(&desc->lock);
  465. action_ret = handle_IRQ_event(irq, action);
  466. if (!noirqdebug)
  467. note_interrupt(irq, desc, action_ret);
  468. raw_spin_lock(&desc->lock);
  469. desc->status &= ~IRQ_INPROGRESS;
  470. out_unlock:
  471. raw_spin_unlock(&desc->lock);
  472. }
  473. /**
  474. * handle_level_irq - Level type irq handler
  475. * @irq: the interrupt number
  476. * @desc: the interrupt description structure for this irq
  477. *
  478. * Level type interrupts are active as long as the hardware line has
  479. * the active level. This may require to mask the interrupt and unmask
  480. * it after the associated handler has acknowledged the device, so the
  481. * interrupt line is back to inactive.
  482. */
  483. void
  484. handle_level_irq(unsigned int irq, struct irq_desc *desc)
  485. {
  486. struct irqaction *action;
  487. irqreturn_t action_ret;
  488. raw_spin_lock(&desc->lock);
  489. mask_ack_irq(desc);
  490. if (unlikely(desc->status & IRQ_INPROGRESS))
  491. goto out_unlock;
  492. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  493. kstat_incr_irqs_this_cpu(irq, desc);
  494. /*
  495. * If its disabled or no action available
  496. * keep it masked and get out of here
  497. */
  498. action = desc->action;
  499. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  500. goto out_unlock;
  501. desc->status |= IRQ_INPROGRESS;
  502. raw_spin_unlock(&desc->lock);
  503. action_ret = handle_IRQ_event(irq, action);
  504. if (!noirqdebug)
  505. note_interrupt(irq, desc, action_ret);
  506. raw_spin_lock(&desc->lock);
  507. desc->status &= ~IRQ_INPROGRESS;
  508. if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
  509. unmask_irq(desc);
  510. out_unlock:
  511. raw_spin_unlock(&desc->lock);
  512. }
  513. EXPORT_SYMBOL_GPL(handle_level_irq);
  514. /**
  515. * handle_fasteoi_irq - irq handler for transparent controllers
  516. * @irq: the interrupt number
  517. * @desc: the interrupt description structure for this irq
  518. *
  519. * Only a single callback will be issued to the chip: an ->eoi()
  520. * call when the interrupt has been serviced. This enables support
  521. * for modern forms of interrupt handlers, which handle the flow
  522. * details in hardware, transparently.
  523. */
  524. void
  525. handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
  526. {
  527. struct irqaction *action;
  528. irqreturn_t action_ret;
  529. raw_spin_lock(&desc->lock);
  530. if (unlikely(desc->status & IRQ_INPROGRESS))
  531. goto out;
  532. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  533. kstat_incr_irqs_this_cpu(irq, desc);
  534. /*
  535. * If its disabled or no action available
  536. * then mask it and get out of here:
  537. */
  538. action = desc->action;
  539. if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
  540. desc->status |= IRQ_PENDING;
  541. mask_irq(desc);
  542. goto out;
  543. }
  544. desc->status |= IRQ_INPROGRESS;
  545. desc->status &= ~IRQ_PENDING;
  546. raw_spin_unlock(&desc->lock);
  547. action_ret = handle_IRQ_event(irq, action);
  548. if (!noirqdebug)
  549. note_interrupt(irq, desc, action_ret);
  550. raw_spin_lock(&desc->lock);
  551. desc->status &= ~IRQ_INPROGRESS;
  552. out:
  553. desc->irq_data.chip->irq_eoi(&desc->irq_data);
  554. raw_spin_unlock(&desc->lock);
  555. }
  556. /**
  557. * handle_edge_irq - edge type IRQ handler
  558. * @irq: the interrupt number
  559. * @desc: the interrupt description structure for this irq
  560. *
  561. * Interrupt occures on the falling and/or rising edge of a hardware
  562. * signal. The occurence is latched into the irq controller hardware
  563. * and must be acked in order to be reenabled. After the ack another
  564. * interrupt can happen on the same source even before the first one
  565. * is handled by the associated event handler. If this happens it
  566. * might be necessary to disable (mask) the interrupt depending on the
  567. * controller hardware. This requires to reenable the interrupt inside
  568. * of the loop which handles the interrupts which have arrived while
  569. * the handler was running. If all pending interrupts are handled, the
  570. * loop is left.
  571. */
  572. void
  573. handle_edge_irq(unsigned int irq, struct irq_desc *desc)
  574. {
  575. raw_spin_lock(&desc->lock);
  576. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  577. /*
  578. * If we're currently running this IRQ, or its disabled,
  579. * we shouldn't process the IRQ. Mark it pending, handle
  580. * the necessary masking and go out
  581. */
  582. if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) ||
  583. !desc->action)) {
  584. desc->status |= (IRQ_PENDING | IRQ_MASKED);
  585. mask_ack_irq(desc);
  586. goto out_unlock;
  587. }
  588. kstat_incr_irqs_this_cpu(irq, desc);
  589. /* Start handling the irq */
  590. desc->irq_data.chip->irq_ack(&desc->irq_data);
  591. /* Mark the IRQ currently in progress.*/
  592. desc->status |= IRQ_INPROGRESS;
  593. do {
  594. struct irqaction *action = desc->action;
  595. irqreturn_t action_ret;
  596. if (unlikely(!action)) {
  597. mask_irq(desc);
  598. goto out_unlock;
  599. }
  600. /*
  601. * When another irq arrived while we were handling
  602. * one, we could have masked the irq.
  603. * Renable it, if it was not disabled in meantime.
  604. */
  605. if (unlikely((desc->status &
  606. (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
  607. (IRQ_PENDING | IRQ_MASKED))) {
  608. unmask_irq(desc);
  609. }
  610. desc->status &= ~IRQ_PENDING;
  611. raw_spin_unlock(&desc->lock);
  612. action_ret = handle_IRQ_event(irq, action);
  613. if (!noirqdebug)
  614. note_interrupt(irq, desc, action_ret);
  615. raw_spin_lock(&desc->lock);
  616. } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
  617. desc->status &= ~IRQ_INPROGRESS;
  618. out_unlock:
  619. raw_spin_unlock(&desc->lock);
  620. }
  621. /**
  622. * handle_percpu_irq - Per CPU local irq handler
  623. * @irq: the interrupt number
  624. * @desc: the interrupt description structure for this irq
  625. *
  626. * Per CPU interrupts on SMP machines without locking requirements
  627. */
  628. void
  629. handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
  630. {
  631. irqreturn_t action_ret;
  632. kstat_incr_irqs_this_cpu(irq, desc);
  633. if (desc->irq_data.chip->irq_ack)
  634. desc->irq_data.chip->irq_ack(&desc->irq_data);
  635. action_ret = handle_IRQ_event(irq, desc->action);
  636. if (!noirqdebug)
  637. note_interrupt(irq, desc, action_ret);
  638. if (desc->irq_data.chip->irq_eoi)
  639. desc->irq_data.chip->irq_eoi(&desc->irq_data);
  640. }
  641. void
  642. __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
  643. const char *name)
  644. {
  645. struct irq_desc *desc = irq_to_desc(irq);
  646. unsigned long flags;
  647. if (!desc) {
  648. printk(KERN_ERR
  649. "Trying to install type control for IRQ%d\n", irq);
  650. return;
  651. }
  652. if (!handle)
  653. handle = handle_bad_irq;
  654. else if (desc->irq_data.chip == &no_irq_chip) {
  655. printk(KERN_WARNING "Trying to install %sinterrupt handler "
  656. "for IRQ%d\n", is_chained ? "chained " : "", irq);
  657. /*
  658. * Some ARM implementations install a handler for really dumb
  659. * interrupt hardware without setting an irq_chip. This worked
  660. * with the ARM no_irq_chip but the check in setup_irq would
  661. * prevent us to setup the interrupt at all. Switch it to
  662. * dummy_irq_chip for easy transition.
  663. */
  664. desc->irq_data.chip = &dummy_irq_chip;
  665. }
  666. chip_bus_lock(desc);
  667. raw_spin_lock_irqsave(&desc->lock, flags);
  668. /* Uninstall? */
  669. if (handle == handle_bad_irq) {
  670. if (desc->irq_data.chip != &no_irq_chip)
  671. mask_ack_irq(desc);
  672. desc->status |= IRQ_DISABLED;
  673. desc->depth = 1;
  674. }
  675. desc->handle_irq = handle;
  676. desc->name = name;
  677. if (handle != handle_bad_irq && is_chained) {
  678. desc->status &= ~IRQ_DISABLED;
  679. desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
  680. desc->depth = 0;
  681. desc->irq_data.chip->irq_startup(&desc->irq_data);
  682. }
  683. raw_spin_unlock_irqrestore(&desc->lock, flags);
  684. chip_bus_sync_unlock(desc);
  685. }
  686. EXPORT_SYMBOL_GPL(__set_irq_handler);
  687. void
  688. set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
  689. irq_flow_handler_t handle)
  690. {
  691. set_irq_chip(irq, chip);
  692. __set_irq_handler(irq, handle, 0, NULL);
  693. }
  694. void
  695. set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
  696. irq_flow_handler_t handle, const char *name)
  697. {
  698. set_irq_chip(irq, chip);
  699. __set_irq_handler(irq, handle, 0, name);
  700. }
  701. void set_irq_noprobe(unsigned int irq)
  702. {
  703. struct irq_desc *desc = irq_to_desc(irq);
  704. unsigned long flags;
  705. if (!desc) {
  706. printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
  707. return;
  708. }
  709. raw_spin_lock_irqsave(&desc->lock, flags);
  710. desc->status |= IRQ_NOPROBE;
  711. raw_spin_unlock_irqrestore(&desc->lock, flags);
  712. }
  713. void set_irq_probe(unsigned int irq)
  714. {
  715. struct irq_desc *desc = irq_to_desc(irq);
  716. unsigned long flags;
  717. if (!desc) {
  718. printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
  719. return;
  720. }
  721. raw_spin_lock_irqsave(&desc->lock, flags);
  722. desc->status &= ~IRQ_NOPROBE;
  723. raw_spin_unlock_irqrestore(&desc->lock, flags);
  724. }