2 * linux/kernel/irq/chip.c
4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
7 * This file contains the core interrupt handling code, for irq-chip
10 * Detailed information is available in Documentation/DocBook/genericirq
13 #include <linux/irq.h>
14 #include <linux/msi.h>
15 #include <linux/module.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
19 #include "internals.h"
22 * dynamic_irq_init - initialize a dynamically allocated irq
23 * @irq: irq number to initialize
25 void dynamic_irq_init(unsigned int irq
)
27 struct irq_desc
*desc
;
30 desc
= irq_to_desc(irq
);
32 WARN(1, KERN_ERR
"Trying to initialize invalid IRQ%d\n", irq
);
36 /* Ensure we don't have left over values from a previous use of this irq */
37 raw_spin_lock_irqsave(&desc
->lock
, flags
);
38 desc
->status
= IRQ_DISABLED
;
39 desc
->chip
= &no_irq_chip
;
40 desc
->handle_irq
= handle_bad_irq
;
42 desc
->msi_desc
= NULL
;
43 desc
->handler_data
= NULL
;
44 desc
->chip_data
= NULL
;
47 desc
->irqs_unhandled
= 0;
49 cpumask_setall(desc
->affinity
);
50 #ifdef CONFIG_GENERIC_PENDING_IRQ
51 cpumask_clear(desc
->pending_mask
);
54 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
58 * dynamic_irq_cleanup - cleanup a dynamically allocated irq
59 * @irq: irq number to initialize
61 void dynamic_irq_cleanup(unsigned int irq
)
63 struct irq_desc
*desc
= irq_to_desc(irq
);
67 WARN(1, KERN_ERR
"Trying to cleanup invalid IRQ%d\n", irq
);
71 raw_spin_lock_irqsave(&desc
->lock
, flags
);
73 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
74 WARN(1, KERN_ERR
"Destroying IRQ%d without calling free_irq\n",
78 desc
->msi_desc
= NULL
;
79 desc
->handler_data
= NULL
;
80 desc
->chip_data
= NULL
;
81 desc
->handle_irq
= handle_bad_irq
;
82 desc
->chip
= &no_irq_chip
;
84 clear_kstat_irqs(desc
);
85 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
90 * set_irq_chip - set the irq chip for an irq
92 * @chip: pointer to irq chip description structure
94 int set_irq_chip(unsigned int irq
, struct irq_chip
*chip
)
96 struct irq_desc
*desc
= irq_to_desc(irq
);
100 WARN(1, KERN_ERR
"Trying to install chip for IRQ%d\n", irq
);
107 raw_spin_lock_irqsave(&desc
->lock
, flags
);
108 irq_chip_set_defaults(chip
);
110 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
114 EXPORT_SYMBOL(set_irq_chip
);
117 * set_irq_type - set the irq trigger type for an irq
119 * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
121 int set_irq_type(unsigned int irq
, unsigned int type
)
123 struct irq_desc
*desc
= irq_to_desc(irq
);
128 printk(KERN_ERR
"Trying to set irq type for IRQ%d\n", irq
);
132 type
&= IRQ_TYPE_SENSE_MASK
;
133 if (type
== IRQ_TYPE_NONE
)
136 raw_spin_lock_irqsave(&desc
->lock
, flags
);
137 ret
= __irq_set_trigger(desc
, irq
, type
);
138 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
141 EXPORT_SYMBOL(set_irq_type
);
144 * set_irq_data - set irq type data for an irq
145 * @irq: Interrupt number
146 * @data: Pointer to interrupt specific data
148 * Set the hardware irq controller data for an irq
150 int set_irq_data(unsigned int irq
, void *data
)
152 struct irq_desc
*desc
= irq_to_desc(irq
);
157 "Trying to install controller data for IRQ%d\n", irq
);
161 raw_spin_lock_irqsave(&desc
->lock
, flags
);
162 desc
->handler_data
= data
;
163 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
166 EXPORT_SYMBOL(set_irq_data
);
169 * set_irq_msi - set MSI descriptor data for an irq
170 * @irq: Interrupt number
171 * @entry: Pointer to MSI descriptor data
173 * Set the MSI descriptor entry for an irq
175 int set_irq_msi(unsigned int irq
, struct msi_desc
*entry
)
177 struct irq_desc
*desc
= irq_to_desc(irq
);
182 "Trying to install msi data for IRQ%d\n", irq
);
186 raw_spin_lock_irqsave(&desc
->lock
, flags
);
187 desc
->msi_desc
= entry
;
190 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
195 * set_irq_chip_data - set irq chip data for an irq
196 * @irq: Interrupt number
197 * @data: Pointer to chip specific data
199 * Set the hardware irq chip data for an irq
201 int set_irq_chip_data(unsigned int irq
, void *data
)
203 struct irq_desc
*desc
= irq_to_desc(irq
);
208 "Trying to install chip data for IRQ%d\n", irq
);
213 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
217 raw_spin_lock_irqsave(&desc
->lock
, flags
);
218 desc
->chip_data
= data
;
219 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
223 EXPORT_SYMBOL(set_irq_chip_data
);
226 * set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
228 * @irq: Interrupt number
229 * @nest: 0 to clear / 1 to set the IRQ_NESTED_THREAD flag
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.
236 void set_irq_nested_thread(unsigned int irq
, int nest
)
238 struct irq_desc
*desc
= irq_to_desc(irq
);
244 raw_spin_lock_irqsave(&desc
->lock
, flags
);
246 desc
->status
|= IRQ_NESTED_THREAD
;
248 desc
->status
&= ~IRQ_NESTED_THREAD
;
249 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
251 EXPORT_SYMBOL_GPL(set_irq_nested_thread
);
254 * default enable function
256 static void default_enable(unsigned int irq
)
258 struct irq_desc
*desc
= irq_to_desc(irq
);
260 desc
->chip
->unmask(irq
);
261 desc
->status
&= ~IRQ_MASKED
;
265 * default disable function
267 static void default_disable(unsigned int irq
)
272 * default startup function
274 static unsigned int default_startup(unsigned int irq
)
276 struct irq_desc
*desc
= irq_to_desc(irq
);
278 desc
->chip
->enable(irq
);
283 * default shutdown function
285 static void default_shutdown(unsigned int irq
)
287 struct irq_desc
*desc
= irq_to_desc(irq
);
289 desc
->chip
->mask(irq
);
290 desc
->status
|= IRQ_MASKED
;
294 * Fixup enable/disable function pointers
296 void irq_chip_set_defaults(struct irq_chip
*chip
)
299 chip
->enable
= default_enable
;
301 chip
->disable
= default_disable
;
303 chip
->startup
= default_startup
;
305 * We use chip->disable, when the user provided its own. When
306 * we have default_disable set for chip->disable, then we need
307 * to use default_shutdown, otherwise the irq line is not
308 * disabled on free_irq():
311 chip
->shutdown
= chip
->disable
!= default_disable
?
312 chip
->disable
: default_shutdown
;
314 chip
->name
= chip
->typename
;
316 chip
->end
= dummy_irq_chip
.end
;
319 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
321 if (desc
->chip
->mask_ack
)
322 desc
->chip
->mask_ack(irq
);
324 desc
->chip
->mask(irq
);
326 desc
->chip
->ack(irq
);
331 * handle_nested_irq - Handle a nested irq from a irq thread
332 * @irq: the interrupt number
334 * Handle interrupts which are nested into a threaded interrupt
335 * handler. The handler function is called inside the calling
338 void handle_nested_irq(unsigned int irq
)
340 struct irq_desc
*desc
= irq_to_desc(irq
);
341 struct irqaction
*action
;
342 irqreturn_t action_ret
;
346 raw_spin_lock_irq(&desc
->lock
);
348 kstat_incr_irqs_this_cpu(irq
, desc
);
350 action
= desc
->action
;
351 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
354 desc
->status
|= IRQ_INPROGRESS
;
355 raw_spin_unlock_irq(&desc
->lock
);
357 action_ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
359 note_interrupt(irq
, desc
, action_ret
);
361 raw_spin_lock_irq(&desc
->lock
);
362 desc
->status
&= ~IRQ_INPROGRESS
;
365 raw_spin_unlock_irq(&desc
->lock
);
367 EXPORT_SYMBOL_GPL(handle_nested_irq
);
370 * handle_simple_irq - Simple and software-decoded IRQs.
371 * @irq: the interrupt number
372 * @desc: the interrupt description structure for this irq
374 * Simple interrupts are either sent from a demultiplexing interrupt
375 * handler or come from hardware, where no interrupt hardware control
378 * Note: The caller is expected to handle the ack, clear, mask and
379 * unmask issues if necessary.
382 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
384 struct irqaction
*action
;
385 irqreturn_t action_ret
;
387 raw_spin_lock(&desc
->lock
);
389 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
391 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
392 kstat_incr_irqs_this_cpu(irq
, desc
);
394 action
= desc
->action
;
395 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
398 desc
->status
|= IRQ_INPROGRESS
;
399 raw_spin_unlock(&desc
->lock
);
401 action_ret
= handle_IRQ_event(irq
, action
);
403 note_interrupt(irq
, desc
, action_ret
);
405 raw_spin_lock(&desc
->lock
);
406 desc
->status
&= ~IRQ_INPROGRESS
;
408 raw_spin_unlock(&desc
->lock
);
412 * handle_level_irq - Level type irq handler
413 * @irq: the interrupt number
414 * @desc: the interrupt description structure for this irq
416 * Level type interrupts are active as long as the hardware line has
417 * the active level. This may require to mask the interrupt and unmask
418 * it after the associated handler has acknowledged the device, so the
419 * interrupt line is back to inactive.
422 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
424 struct irqaction
*action
;
425 irqreturn_t action_ret
;
427 raw_spin_lock(&desc
->lock
);
428 mask_ack_irq(desc
, irq
);
430 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
432 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
433 kstat_incr_irqs_this_cpu(irq
, desc
);
436 * If its disabled or no action available
437 * keep it masked and get out of here
439 action
= desc
->action
;
440 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
443 desc
->status
|= IRQ_INPROGRESS
;
444 raw_spin_unlock(&desc
->lock
);
446 action_ret
= handle_IRQ_event(irq
, action
);
448 note_interrupt(irq
, desc
, action_ret
);
450 raw_spin_lock(&desc
->lock
);
451 desc
->status
&= ~IRQ_INPROGRESS
;
453 if (unlikely(desc
->status
& IRQ_ONESHOT
))
454 desc
->status
|= IRQ_MASKED
;
455 else if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
456 desc
->chip
->unmask(irq
);
458 raw_spin_unlock(&desc
->lock
);
460 EXPORT_SYMBOL_GPL(handle_level_irq
);
463 * handle_fasteoi_irq - irq handler for transparent controllers
464 * @irq: the interrupt number
465 * @desc: the interrupt description structure for this irq
467 * Only a single callback will be issued to the chip: an ->eoi()
468 * call when the interrupt has been serviced. This enables support
469 * for modern forms of interrupt handlers, which handle the flow
470 * details in hardware, transparently.
473 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
475 struct irqaction
*action
;
476 irqreturn_t action_ret
;
478 raw_spin_lock(&desc
->lock
);
480 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
483 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
484 kstat_incr_irqs_this_cpu(irq
, desc
);
487 * If its disabled or no action available
488 * then mask it and get out of here:
490 action
= desc
->action
;
491 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
492 desc
->status
|= IRQ_PENDING
;
493 if (desc
->chip
->mask
)
494 desc
->chip
->mask(irq
);
498 desc
->status
|= IRQ_INPROGRESS
;
499 desc
->status
&= ~IRQ_PENDING
;
500 raw_spin_unlock(&desc
->lock
);
502 action_ret
= handle_IRQ_event(irq
, action
);
504 note_interrupt(irq
, desc
, action_ret
);
506 raw_spin_lock(&desc
->lock
);
507 desc
->status
&= ~IRQ_INPROGRESS
;
509 desc
->chip
->eoi(irq
);
511 raw_spin_unlock(&desc
->lock
);
515 * handle_edge_irq - edge type IRQ handler
516 * @irq: the interrupt number
517 * @desc: the interrupt description structure for this irq
519 * Interrupt occures on the falling and/or rising edge of a hardware
520 * signal. The occurence is latched into the irq controller hardware
521 * and must be acked in order to be reenabled. After the ack another
522 * interrupt can happen on the same source even before the first one
523 * is handled by the associated event handler. If this happens it
524 * might be necessary to disable (mask) the interrupt depending on the
525 * controller hardware. This requires to reenable the interrupt inside
526 * of the loop which handles the interrupts which have arrived while
527 * the handler was running. If all pending interrupts are handled, the
531 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
533 raw_spin_lock(&desc
->lock
);
535 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
538 * If we're currently running this IRQ, or its disabled,
539 * we shouldn't process the IRQ. Mark it pending, handle
540 * the necessary masking and go out
542 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
544 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
545 mask_ack_irq(desc
, irq
);
548 kstat_incr_irqs_this_cpu(irq
, desc
);
550 /* Start handling the irq */
552 desc
->chip
->ack(irq
);
554 /* Mark the IRQ currently in progress.*/
555 desc
->status
|= IRQ_INPROGRESS
;
558 struct irqaction
*action
= desc
->action
;
559 irqreturn_t action_ret
;
561 if (unlikely(!action
)) {
562 desc
->chip
->mask(irq
);
567 * When another irq arrived while we were handling
568 * one, we could have masked the irq.
569 * Renable it, if it was not disabled in meantime.
571 if (unlikely((desc
->status
&
572 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
573 (IRQ_PENDING
| IRQ_MASKED
))) {
574 desc
->chip
->unmask(irq
);
575 desc
->status
&= ~IRQ_MASKED
;
578 desc
->status
&= ~IRQ_PENDING
;
579 raw_spin_unlock(&desc
->lock
);
580 action_ret
= handle_IRQ_event(irq
, action
);
582 note_interrupt(irq
, desc
, action_ret
);
583 raw_spin_lock(&desc
->lock
);
585 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
587 desc
->status
&= ~IRQ_INPROGRESS
;
589 raw_spin_unlock(&desc
->lock
);
593 * handle_percpu_irq - Per CPU local irq handler
594 * @irq: the interrupt number
595 * @desc: the interrupt description structure for this irq
597 * Per CPU interrupts on SMP machines without locking requirements
600 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
602 irqreturn_t action_ret
;
604 kstat_incr_irqs_this_cpu(irq
, desc
);
607 desc
->chip
->ack(irq
);
609 action_ret
= handle_IRQ_event(irq
, desc
->action
);
611 note_interrupt(irq
, desc
, action_ret
);
614 desc
->chip
->eoi(irq
);
618 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
621 struct irq_desc
*desc
= irq_to_desc(irq
);
626 "Trying to install type control for IRQ%d\n", irq
);
631 handle
= handle_bad_irq
;
632 else if (desc
->chip
== &no_irq_chip
) {
633 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
634 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
636 * Some ARM implementations install a handler for really dumb
637 * interrupt hardware without setting an irq_chip. This worked
638 * with the ARM no_irq_chip but the check in setup_irq would
639 * prevent us to setup the interrupt at all. Switch it to
640 * dummy_irq_chip for easy transition.
642 desc
->chip
= &dummy_irq_chip
;
645 chip_bus_lock(irq
, desc
);
646 raw_spin_lock_irqsave(&desc
->lock
, flags
);
649 if (handle
== handle_bad_irq
) {
650 if (desc
->chip
!= &no_irq_chip
)
651 mask_ack_irq(desc
, irq
);
652 desc
->status
|= IRQ_DISABLED
;
655 desc
->handle_irq
= handle
;
658 if (handle
!= handle_bad_irq
&& is_chained
) {
659 desc
->status
&= ~IRQ_DISABLED
;
660 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
662 desc
->chip
->startup(irq
);
664 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
665 chip_bus_sync_unlock(irq
, desc
);
667 EXPORT_SYMBOL_GPL(__set_irq_handler
);
670 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
671 irq_flow_handler_t handle
)
673 set_irq_chip(irq
, chip
);
674 __set_irq_handler(irq
, handle
, 0, NULL
);
678 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
679 irq_flow_handler_t handle
, const char *name
)
681 set_irq_chip(irq
, chip
);
682 __set_irq_handler(irq
, handle
, 0, name
);
685 void __init
set_irq_noprobe(unsigned int irq
)
687 struct irq_desc
*desc
= irq_to_desc(irq
);
691 printk(KERN_ERR
"Trying to mark IRQ%d non-probeable\n", irq
);
695 raw_spin_lock_irqsave(&desc
->lock
, flags
);
696 desc
->status
|= IRQ_NOPROBE
;
697 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
700 void __init
set_irq_probe(unsigned int irq
)
702 struct irq_desc
*desc
= irq_to_desc(irq
);
706 printk(KERN_ERR
"Trying to mark IRQ%d probeable\n", irq
);
710 raw_spin_lock_irqsave(&desc
->lock
, flags
);
711 desc
->status
&= ~IRQ_NOPROBE
;
712 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);