chip.c 20 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840
  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(unsigned int irq)
  269. {
  270. struct irq_desc *desc = irq_to_desc(irq);
  271. desc->irq_data.chip->irq_enable(&desc->irq_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 void compat_bus_lock(struct irq_data *data)
  317. {
  318. data->chip->bus_lock(data->irq);
  319. }
  320. static void compat_bus_sync_unlock(struct irq_data *data)
  321. {
  322. data->chip->bus_sync_unlock(data->irq);
  323. }
  324. /*
  325. * Fixup enable/disable function pointers
  326. */
  327. void irq_chip_set_defaults(struct irq_chip *chip)
  328. {
  329. /*
  330. * Compat fixup functions need to be before we set the
  331. * defaults for enable/disable/startup/shutdown
  332. */
  333. if (chip->enable)
  334. chip->irq_enable = compat_irq_enable;
  335. if (chip->disable)
  336. chip->irq_disable = compat_irq_disable;
  337. if (chip->shutdown)
  338. chip->irq_shutdown = compat_irq_shutdown;
  339. /*
  340. * The real defaults
  341. */
  342. if (!chip->irq_enable)
  343. chip->irq_enable = default_enable;
  344. if (!chip->irq_disable)
  345. chip->irq_disable = default_disable;
  346. if (!chip->startup)
  347. chip->startup = default_startup;
  348. /*
  349. * We use chip->irq_disable, when the user provided its own. When
  350. * we have default_disable set for chip->irq_disable, then we need
  351. * to use default_shutdown, otherwise the irq line is not
  352. * disabled on free_irq():
  353. */
  354. if (!chip->irq_shutdown)
  355. chip->irq_shutdown = chip->irq_disable != default_disable ?
  356. chip->irq_disable : default_shutdown;
  357. if (!chip->end)
  358. chip->end = dummy_irq_chip.end;
  359. /*
  360. * Now fix up the remaining compat handlers
  361. */
  362. if (chip->bus_lock)
  363. chip->irq_bus_lock = compat_bus_lock;
  364. if (chip->bus_sync_unlock)
  365. chip->irq_bus_sync_unlock = compat_bus_sync_unlock;
  366. if (chip->mask)
  367. chip->irq_mask = compat_irq_mask;
  368. if (chip->unmask)
  369. chip->irq_unmask = compat_irq_unmask;
  370. if (chip->ack)
  371. chip->irq_ack = compat_irq_ack;
  372. if (chip->mask_ack)
  373. chip->irq_mask_ack = compat_irq_mask_ack;
  374. if (chip->eoi)
  375. chip->irq_eoi = compat_irq_eoi;
  376. }
  377. static inline void mask_ack_irq(struct irq_desc *desc)
  378. {
  379. if (desc->irq_data.chip->irq_mask_ack)
  380. desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
  381. else {
  382. desc->irq_data.chip->irq_mask(&desc->irq_data);
  383. if (desc->irq_data.chip->irq_ack)
  384. desc->irq_data.chip->irq_ack(&desc->irq_data);
  385. }
  386. desc->status |= IRQ_MASKED;
  387. }
  388. static inline void mask_irq(struct irq_desc *desc)
  389. {
  390. if (desc->irq_data.chip->irq_mask) {
  391. desc->irq_data.chip->irq_mask(&desc->irq_data);
  392. desc->status |= IRQ_MASKED;
  393. }
  394. }
  395. static inline void unmask_irq(struct irq_desc *desc)
  396. {
  397. if (desc->irq_data.chip->irq_unmask) {
  398. desc->irq_data.chip->irq_unmask(&desc->irq_data);
  399. desc->status &= ~IRQ_MASKED;
  400. }
  401. }
  402. /*
  403. * handle_nested_irq - Handle a nested irq from a irq thread
  404. * @irq: the interrupt number
  405. *
  406. * Handle interrupts which are nested into a threaded interrupt
  407. * handler. The handler function is called inside the calling
  408. * threads context.
  409. */
  410. void handle_nested_irq(unsigned int irq)
  411. {
  412. struct irq_desc *desc = irq_to_desc(irq);
  413. struct irqaction *action;
  414. irqreturn_t action_ret;
  415. might_sleep();
  416. raw_spin_lock_irq(&desc->lock);
  417. kstat_incr_irqs_this_cpu(irq, desc);
  418. action = desc->action;
  419. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  420. goto out_unlock;
  421. desc->status |= IRQ_INPROGRESS;
  422. raw_spin_unlock_irq(&desc->lock);
  423. action_ret = action->thread_fn(action->irq, action->dev_id);
  424. if (!noirqdebug)
  425. note_interrupt(irq, desc, action_ret);
  426. raw_spin_lock_irq(&desc->lock);
  427. desc->status &= ~IRQ_INPROGRESS;
  428. out_unlock:
  429. raw_spin_unlock_irq(&desc->lock);
  430. }
  431. EXPORT_SYMBOL_GPL(handle_nested_irq);
  432. /**
  433. * handle_simple_irq - Simple and software-decoded IRQs.
  434. * @irq: the interrupt number
  435. * @desc: the interrupt description structure for this irq
  436. *
  437. * Simple interrupts are either sent from a demultiplexing interrupt
  438. * handler or come from hardware, where no interrupt hardware control
  439. * is necessary.
  440. *
  441. * Note: The caller is expected to handle the ack, clear, mask and
  442. * unmask issues if necessary.
  443. */
  444. void
  445. handle_simple_irq(unsigned int irq, struct irq_desc *desc)
  446. {
  447. struct irqaction *action;
  448. irqreturn_t action_ret;
  449. raw_spin_lock(&desc->lock);
  450. if (unlikely(desc->status & IRQ_INPROGRESS))
  451. goto out_unlock;
  452. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  453. kstat_incr_irqs_this_cpu(irq, desc);
  454. action = desc->action;
  455. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  456. goto out_unlock;
  457. desc->status |= IRQ_INPROGRESS;
  458. raw_spin_unlock(&desc->lock);
  459. action_ret = handle_IRQ_event(irq, action);
  460. if (!noirqdebug)
  461. note_interrupt(irq, desc, action_ret);
  462. raw_spin_lock(&desc->lock);
  463. desc->status &= ~IRQ_INPROGRESS;
  464. out_unlock:
  465. raw_spin_unlock(&desc->lock);
  466. }
  467. /**
  468. * handle_level_irq - Level type irq handler
  469. * @irq: the interrupt number
  470. * @desc: the interrupt description structure for this irq
  471. *
  472. * Level type interrupts are active as long as the hardware line has
  473. * the active level. This may require to mask the interrupt and unmask
  474. * it after the associated handler has acknowledged the device, so the
  475. * interrupt line is back to inactive.
  476. */
  477. void
  478. handle_level_irq(unsigned int irq, struct irq_desc *desc)
  479. {
  480. struct irqaction *action;
  481. irqreturn_t action_ret;
  482. raw_spin_lock(&desc->lock);
  483. mask_ack_irq(desc);
  484. if (unlikely(desc->status & IRQ_INPROGRESS))
  485. goto out_unlock;
  486. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  487. kstat_incr_irqs_this_cpu(irq, desc);
  488. /*
  489. * If its disabled or no action available
  490. * keep it masked and get out of here
  491. */
  492. action = desc->action;
  493. if (unlikely(!action || (desc->status & IRQ_DISABLED)))
  494. goto out_unlock;
  495. desc->status |= IRQ_INPROGRESS;
  496. raw_spin_unlock(&desc->lock);
  497. action_ret = handle_IRQ_event(irq, action);
  498. if (!noirqdebug)
  499. note_interrupt(irq, desc, action_ret);
  500. raw_spin_lock(&desc->lock);
  501. desc->status &= ~IRQ_INPROGRESS;
  502. if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
  503. unmask_irq(desc);
  504. out_unlock:
  505. raw_spin_unlock(&desc->lock);
  506. }
  507. EXPORT_SYMBOL_GPL(handle_level_irq);
  508. /**
  509. * handle_fasteoi_irq - irq handler for transparent controllers
  510. * @irq: the interrupt number
  511. * @desc: the interrupt description structure for this irq
  512. *
  513. * Only a single callback will be issued to the chip: an ->eoi()
  514. * call when the interrupt has been serviced. This enables support
  515. * for modern forms of interrupt handlers, which handle the flow
  516. * details in hardware, transparently.
  517. */
  518. void
  519. handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
  520. {
  521. struct irqaction *action;
  522. irqreturn_t action_ret;
  523. raw_spin_lock(&desc->lock);
  524. if (unlikely(desc->status & IRQ_INPROGRESS))
  525. goto out;
  526. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  527. kstat_incr_irqs_this_cpu(irq, desc);
  528. /*
  529. * If its disabled or no action available
  530. * then mask it and get out of here:
  531. */
  532. action = desc->action;
  533. if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
  534. desc->status |= IRQ_PENDING;
  535. mask_irq(desc);
  536. goto out;
  537. }
  538. desc->status |= IRQ_INPROGRESS;
  539. desc->status &= ~IRQ_PENDING;
  540. raw_spin_unlock(&desc->lock);
  541. action_ret = handle_IRQ_event(irq, action);
  542. if (!noirqdebug)
  543. note_interrupt(irq, desc, action_ret);
  544. raw_spin_lock(&desc->lock);
  545. desc->status &= ~IRQ_INPROGRESS;
  546. out:
  547. desc->irq_data.chip->irq_eoi(&desc->irq_data);
  548. raw_spin_unlock(&desc->lock);
  549. }
  550. /**
  551. * handle_edge_irq - edge type IRQ handler
  552. * @irq: the interrupt number
  553. * @desc: the interrupt description structure for this irq
  554. *
  555. * Interrupt occures on the falling and/or rising edge of a hardware
  556. * signal. The occurence is latched into the irq controller hardware
  557. * and must be acked in order to be reenabled. After the ack another
  558. * interrupt can happen on the same source even before the first one
  559. * is handled by the associated event handler. If this happens it
  560. * might be necessary to disable (mask) the interrupt depending on the
  561. * controller hardware. This requires to reenable the interrupt inside
  562. * of the loop which handles the interrupts which have arrived while
  563. * the handler was running. If all pending interrupts are handled, the
  564. * loop is left.
  565. */
  566. void
  567. handle_edge_irq(unsigned int irq, struct irq_desc *desc)
  568. {
  569. raw_spin_lock(&desc->lock);
  570. desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
  571. /*
  572. * If we're currently running this IRQ, or its disabled,
  573. * we shouldn't process the IRQ. Mark it pending, handle
  574. * the necessary masking and go out
  575. */
  576. if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) ||
  577. !desc->action)) {
  578. desc->status |= (IRQ_PENDING | IRQ_MASKED);
  579. mask_ack_irq(desc);
  580. goto out_unlock;
  581. }
  582. kstat_incr_irqs_this_cpu(irq, desc);
  583. /* Start handling the irq */
  584. desc->irq_data.chip->irq_ack(&desc->irq_data);
  585. /* Mark the IRQ currently in progress.*/
  586. desc->status |= IRQ_INPROGRESS;
  587. do {
  588. struct irqaction *action = desc->action;
  589. irqreturn_t action_ret;
  590. if (unlikely(!action)) {
  591. mask_irq(desc);
  592. goto out_unlock;
  593. }
  594. /*
  595. * When another irq arrived while we were handling
  596. * one, we could have masked the irq.
  597. * Renable it, if it was not disabled in meantime.
  598. */
  599. if (unlikely((desc->status &
  600. (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
  601. (IRQ_PENDING | IRQ_MASKED))) {
  602. unmask_irq(desc);
  603. }
  604. desc->status &= ~IRQ_PENDING;
  605. raw_spin_unlock(&desc->lock);
  606. action_ret = handle_IRQ_event(irq, action);
  607. if (!noirqdebug)
  608. note_interrupt(irq, desc, action_ret);
  609. raw_spin_lock(&desc->lock);
  610. } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
  611. desc->status &= ~IRQ_INPROGRESS;
  612. out_unlock:
  613. raw_spin_unlock(&desc->lock);
  614. }
  615. /**
  616. * handle_percpu_irq - Per CPU local irq handler
  617. * @irq: the interrupt number
  618. * @desc: the interrupt description structure for this irq
  619. *
  620. * Per CPU interrupts on SMP machines without locking requirements
  621. */
  622. void
  623. handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
  624. {
  625. irqreturn_t action_ret;
  626. kstat_incr_irqs_this_cpu(irq, desc);
  627. if (desc->irq_data.chip->irq_ack)
  628. desc->irq_data.chip->irq_ack(&desc->irq_data);
  629. action_ret = handle_IRQ_event(irq, desc->action);
  630. if (!noirqdebug)
  631. note_interrupt(irq, desc, action_ret);
  632. if (desc->irq_data.chip->irq_eoi)
  633. desc->irq_data.chip->irq_eoi(&desc->irq_data);
  634. }
  635. void
  636. __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
  637. const char *name)
  638. {
  639. struct irq_desc *desc = irq_to_desc(irq);
  640. unsigned long flags;
  641. if (!desc) {
  642. printk(KERN_ERR
  643. "Trying to install type control for IRQ%d\n", irq);
  644. return;
  645. }
  646. if (!handle)
  647. handle = handle_bad_irq;
  648. else if (desc->irq_data.chip == &no_irq_chip) {
  649. printk(KERN_WARNING "Trying to install %sinterrupt handler "
  650. "for IRQ%d\n", is_chained ? "chained " : "", irq);
  651. /*
  652. * Some ARM implementations install a handler for really dumb
  653. * interrupt hardware without setting an irq_chip. This worked
  654. * with the ARM no_irq_chip but the check in setup_irq would
  655. * prevent us to setup the interrupt at all. Switch it to
  656. * dummy_irq_chip for easy transition.
  657. */
  658. desc->irq_data.chip = &dummy_irq_chip;
  659. }
  660. chip_bus_lock(desc);
  661. raw_spin_lock_irqsave(&desc->lock, flags);
  662. /* Uninstall? */
  663. if (handle == handle_bad_irq) {
  664. if (desc->irq_data.chip != &no_irq_chip)
  665. mask_ack_irq(desc);
  666. desc->status |= IRQ_DISABLED;
  667. desc->depth = 1;
  668. }
  669. desc->handle_irq = handle;
  670. desc->name = name;
  671. if (handle != handle_bad_irq && is_chained) {
  672. desc->status &= ~IRQ_DISABLED;
  673. desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
  674. desc->depth = 0;
  675. desc->irq_data.chip->startup(irq);
  676. }
  677. raw_spin_unlock_irqrestore(&desc->lock, flags);
  678. chip_bus_sync_unlock(desc);
  679. }
  680. EXPORT_SYMBOL_GPL(__set_irq_handler);
  681. void
  682. set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
  683. irq_flow_handler_t handle)
  684. {
  685. set_irq_chip(irq, chip);
  686. __set_irq_handler(irq, handle, 0, NULL);
  687. }
  688. void
  689. set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
  690. irq_flow_handler_t handle, const char *name)
  691. {
  692. set_irq_chip(irq, chip);
  693. __set_irq_handler(irq, handle, 0, name);
  694. }
  695. void set_irq_noprobe(unsigned int irq)
  696. {
  697. struct irq_desc *desc = irq_to_desc(irq);
  698. unsigned long flags;
  699. if (!desc) {
  700. printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
  701. return;
  702. }
  703. raw_spin_lock_irqsave(&desc->lock, flags);
  704. desc->status |= IRQ_NOPROBE;
  705. raw_spin_unlock_irqrestore(&desc->lock, flags);
  706. }
  707. void set_irq_probe(unsigned int irq)
  708. {
  709. struct irq_desc *desc = irq_to_desc(irq);
  710. unsigned long flags;
  711. if (!desc) {
  712. printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
  713. return;
  714. }
  715. raw_spin_lock_irqsave(&desc->lock, flags);
  716. desc->status &= ~IRQ_NOPROBE;
  717. raw_spin_unlock_irqrestore(&desc->lock, flags);
  718. }