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 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 cpus_setall(desc
->affinity
);
51 spin_unlock_irqrestore(&desc
->lock
, flags
);
55 * dynamic_irq_cleanup - cleanup a dynamically allocated irq
56 * @irq: irq number to initialize
58 void dynamic_irq_cleanup(unsigned int irq
)
60 struct irq_desc
*desc
= irq_to_desc(irq
);
64 WARN(1, KERN_ERR
"Trying to cleanup invalid IRQ%d\n", irq
);
68 spin_lock_irqsave(&desc
->lock
, flags
);
70 spin_unlock_irqrestore(&desc
->lock
, flags
);
71 WARN(1, KERN_ERR
"Destroying IRQ%d without calling free_irq\n",
75 desc
->msi_desc
= NULL
;
76 desc
->handler_data
= NULL
;
77 desc
->chip_data
= NULL
;
78 desc
->handle_irq
= handle_bad_irq
;
79 desc
->chip
= &no_irq_chip
;
81 spin_unlock_irqrestore(&desc
->lock
, flags
);
86 * set_irq_chip - set the irq chip for an irq
88 * @chip: pointer to irq chip description structure
90 int set_irq_chip(unsigned int irq
, struct irq_chip
*chip
)
92 struct irq_desc
*desc
= irq_to_desc(irq
);
96 WARN(1, KERN_ERR
"Trying to install chip for IRQ%d\n", irq
);
103 spin_lock_irqsave(&desc
->lock
, flags
);
104 irq_chip_set_defaults(chip
);
106 spin_unlock_irqrestore(&desc
->lock
, flags
);
110 EXPORT_SYMBOL(set_irq_chip
);
113 * set_irq_type - set the irq trigger type for an irq
115 * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
117 int set_irq_type(unsigned int irq
, unsigned int type
)
119 struct irq_desc
*desc
= irq_to_desc(irq
);
124 printk(KERN_ERR
"Trying to set irq type for IRQ%d\n", irq
);
128 if (type
== IRQ_TYPE_NONE
)
131 spin_lock_irqsave(&desc
->lock
, flags
);
132 ret
= __irq_set_trigger(desc
, irq
, type
);
133 spin_unlock_irqrestore(&desc
->lock
, flags
);
136 EXPORT_SYMBOL(set_irq_type
);
139 * set_irq_data - set irq type data for an irq
140 * @irq: Interrupt number
141 * @data: Pointer to interrupt specific data
143 * Set the hardware irq controller data for an irq
145 int set_irq_data(unsigned int irq
, void *data
)
147 struct irq_desc
*desc
= irq_to_desc(irq
);
152 "Trying to install controller data for IRQ%d\n", irq
);
156 spin_lock_irqsave(&desc
->lock
, flags
);
157 desc
->handler_data
= data
;
158 spin_unlock_irqrestore(&desc
->lock
, flags
);
161 EXPORT_SYMBOL(set_irq_data
);
164 * set_irq_data - set irq type data for an irq
165 * @irq: Interrupt number
166 * @entry: Pointer to MSI descriptor data
168 * Set the hardware irq controller data for an irq
170 int set_irq_msi(unsigned int irq
, struct msi_desc
*entry
)
172 struct irq_desc
*desc
= irq_to_desc(irq
);
177 "Trying to install msi data for IRQ%d\n", irq
);
181 spin_lock_irqsave(&desc
->lock
, flags
);
182 desc
->msi_desc
= entry
;
185 spin_unlock_irqrestore(&desc
->lock
, flags
);
190 * set_irq_chip_data - set irq chip data for an irq
191 * @irq: Interrupt number
192 * @data: Pointer to chip specific data
194 * Set the hardware irq chip data for an irq
196 int set_irq_chip_data(unsigned int irq
, void *data
)
198 struct irq_desc
*desc
= irq_to_desc(irq
);
203 "Trying to install chip data for IRQ%d\n", irq
);
208 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
212 spin_lock_irqsave(&desc
->lock
, flags
);
213 desc
->chip_data
= data
;
214 spin_unlock_irqrestore(&desc
->lock
, flags
);
218 EXPORT_SYMBOL(set_irq_chip_data
);
221 * default enable function
223 static void default_enable(unsigned int irq
)
225 struct irq_desc
*desc
= irq_to_desc(irq
);
227 desc
->chip
->unmask(irq
);
228 desc
->status
&= ~IRQ_MASKED
;
232 * default disable function
234 static void default_disable(unsigned int irq
)
239 * default startup function
241 static unsigned int default_startup(unsigned int irq
)
243 struct irq_desc
*desc
= irq_to_desc(irq
);
245 desc
->chip
->enable(irq
);
250 * default shutdown function
252 static void default_shutdown(unsigned int irq
)
254 struct irq_desc
*desc
= irq_to_desc(irq
);
256 desc
->chip
->mask(irq
);
257 desc
->status
|= IRQ_MASKED
;
261 * Fixup enable/disable function pointers
263 void irq_chip_set_defaults(struct irq_chip
*chip
)
266 chip
->enable
= default_enable
;
268 chip
->disable
= default_disable
;
270 chip
->startup
= default_startup
;
272 * We use chip->disable, when the user provided its own. When
273 * we have default_disable set for chip->disable, then we need
274 * to use default_shutdown, otherwise the irq line is not
275 * disabled on free_irq():
278 chip
->shutdown
= chip
->disable
!= default_disable
?
279 chip
->disable
: default_shutdown
;
281 chip
->name
= chip
->typename
;
283 chip
->end
= dummy_irq_chip
.end
;
286 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
288 if (desc
->chip
->mask_ack
)
289 desc
->chip
->mask_ack(irq
);
291 desc
->chip
->mask(irq
);
292 desc
->chip
->ack(irq
);
297 * handle_simple_irq - Simple and software-decoded IRQs.
298 * @irq: the interrupt number
299 * @desc: the interrupt description structure for this irq
301 * Simple interrupts are either sent from a demultiplexing interrupt
302 * handler or come from hardware, where no interrupt hardware control
305 * Note: The caller is expected to handle the ack, clear, mask and
306 * unmask issues if necessary.
309 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
311 struct irqaction
*action
;
312 irqreturn_t action_ret
;
314 spin_lock(&desc
->lock
);
316 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
318 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
319 kstat_incr_irqs_this_cpu(irq
, desc
);
321 action
= desc
->action
;
322 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
325 desc
->status
|= IRQ_INPROGRESS
;
326 spin_unlock(&desc
->lock
);
328 action_ret
= handle_IRQ_event(irq
, action
);
330 note_interrupt(irq
, desc
, action_ret
);
332 spin_lock(&desc
->lock
);
333 desc
->status
&= ~IRQ_INPROGRESS
;
335 spin_unlock(&desc
->lock
);
339 * handle_level_irq - Level type irq handler
340 * @irq: the interrupt number
341 * @desc: the interrupt description structure for this irq
343 * Level type interrupts are active as long as the hardware line has
344 * the active level. This may require to mask the interrupt and unmask
345 * it after the associated handler has acknowledged the device, so the
346 * interrupt line is back to inactive.
349 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
351 struct irqaction
*action
;
352 irqreturn_t action_ret
;
354 spin_lock(&desc
->lock
);
355 mask_ack_irq(desc
, irq
);
356 desc
= irq_remap_to_desc(irq
, desc
);
358 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
360 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
361 kstat_incr_irqs_this_cpu(irq
, desc
);
364 * If its disabled or no action available
365 * keep it masked and get out of here
367 action
= desc
->action
;
368 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
371 desc
->status
|= IRQ_INPROGRESS
;
372 spin_unlock(&desc
->lock
);
374 action_ret
= handle_IRQ_event(irq
, action
);
376 note_interrupt(irq
, desc
, action_ret
);
378 spin_lock(&desc
->lock
);
379 desc
->status
&= ~IRQ_INPROGRESS
;
380 if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
381 desc
->chip
->unmask(irq
);
383 spin_unlock(&desc
->lock
);
387 * handle_fasteoi_irq - irq handler for transparent controllers
388 * @irq: the interrupt number
389 * @desc: the interrupt description structure for this irq
391 * Only a single callback will be issued to the chip: an ->eoi()
392 * call when the interrupt has been serviced. This enables support
393 * for modern forms of interrupt handlers, which handle the flow
394 * details in hardware, transparently.
397 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
399 struct irqaction
*action
;
400 irqreturn_t action_ret
;
402 spin_lock(&desc
->lock
);
404 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
407 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
408 kstat_incr_irqs_this_cpu(irq
, desc
);
411 * If its disabled or no action available
412 * then mask it and get out of here:
414 action
= desc
->action
;
415 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
416 desc
->status
|= IRQ_PENDING
;
417 if (desc
->chip
->mask
)
418 desc
->chip
->mask(irq
);
422 desc
->status
|= IRQ_INPROGRESS
;
423 desc
->status
&= ~IRQ_PENDING
;
424 spin_unlock(&desc
->lock
);
426 action_ret
= handle_IRQ_event(irq
, action
);
428 note_interrupt(irq
, desc
, action_ret
);
430 spin_lock(&desc
->lock
);
431 desc
->status
&= ~IRQ_INPROGRESS
;
433 desc
->chip
->eoi(irq
);
434 desc
= irq_remap_to_desc(irq
, desc
);
436 spin_unlock(&desc
->lock
);
440 * handle_edge_irq - edge type IRQ handler
441 * @irq: the interrupt number
442 * @desc: the interrupt description structure for this irq
444 * Interrupt occures on the falling and/or rising edge of a hardware
445 * signal. The occurence is latched into the irq controller hardware
446 * and must be acked in order to be reenabled. After the ack another
447 * interrupt can happen on the same source even before the first one
448 * is handled by the assosiacted event handler. If this happens it
449 * might be necessary to disable (mask) the interrupt depending on the
450 * controller hardware. This requires to reenable the interrupt inside
451 * of the loop which handles the interrupts which have arrived while
452 * the handler was running. If all pending interrupts are handled, the
456 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
458 spin_lock(&desc
->lock
);
460 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
463 * If we're currently running this IRQ, or its disabled,
464 * we shouldn't process the IRQ. Mark it pending, handle
465 * the necessary masking and go out
467 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
469 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
470 mask_ack_irq(desc
, irq
);
471 desc
= irq_remap_to_desc(irq
, desc
);
474 kstat_incr_irqs_this_cpu(irq
, desc
);
476 /* Start handling the irq */
477 desc
->chip
->ack(irq
);
478 desc
= irq_remap_to_desc(irq
, desc
);
480 /* Mark the IRQ currently in progress.*/
481 desc
->status
|= IRQ_INPROGRESS
;
484 struct irqaction
*action
= desc
->action
;
485 irqreturn_t action_ret
;
487 if (unlikely(!action
)) {
488 desc
->chip
->mask(irq
);
493 * When another irq arrived while we were handling
494 * one, we could have masked the irq.
495 * Renable it, if it was not disabled in meantime.
497 if (unlikely((desc
->status
&
498 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
499 (IRQ_PENDING
| IRQ_MASKED
))) {
500 desc
->chip
->unmask(irq
);
501 desc
->status
&= ~IRQ_MASKED
;
504 desc
->status
&= ~IRQ_PENDING
;
505 spin_unlock(&desc
->lock
);
506 action_ret
= handle_IRQ_event(irq
, action
);
508 note_interrupt(irq
, desc
, action_ret
);
509 spin_lock(&desc
->lock
);
511 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
513 desc
->status
&= ~IRQ_INPROGRESS
;
515 spin_unlock(&desc
->lock
);
519 * handle_percpu_IRQ - Per CPU local irq handler
520 * @irq: the interrupt number
521 * @desc: the interrupt description structure for this irq
523 * Per CPU interrupts on SMP machines without locking requirements
526 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
528 irqreturn_t action_ret
;
530 kstat_incr_irqs_this_cpu(irq
, desc
);
533 desc
->chip
->ack(irq
);
535 action_ret
= handle_IRQ_event(irq
, desc
->action
);
537 note_interrupt(irq
, desc
, action_ret
);
539 if (desc
->chip
->eoi
) {
540 desc
->chip
->eoi(irq
);
541 desc
= irq_remap_to_desc(irq
, desc
);
546 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
549 struct irq_desc
*desc
= irq_to_desc(irq
);
554 "Trying to install type control for IRQ%d\n", irq
);
559 handle
= handle_bad_irq
;
560 else if (desc
->chip
== &no_irq_chip
) {
561 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
562 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
564 * Some ARM implementations install a handler for really dumb
565 * interrupt hardware without setting an irq_chip. This worked
566 * with the ARM no_irq_chip but the check in setup_irq would
567 * prevent us to setup the interrupt at all. Switch it to
568 * dummy_irq_chip for easy transition.
570 desc
->chip
= &dummy_irq_chip
;
573 spin_lock_irqsave(&desc
->lock
, flags
);
576 if (handle
== handle_bad_irq
) {
577 if (desc
->chip
!= &no_irq_chip
) {
578 mask_ack_irq(desc
, irq
);
579 desc
= irq_remap_to_desc(irq
, desc
);
581 desc
->status
|= IRQ_DISABLED
;
584 desc
->handle_irq
= handle
;
587 if (handle
!= handle_bad_irq
&& is_chained
) {
588 desc
->status
&= ~IRQ_DISABLED
;
589 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
591 desc
->chip
->startup(irq
);
593 spin_unlock_irqrestore(&desc
->lock
, flags
);
597 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
598 irq_flow_handler_t handle
)
600 set_irq_chip(irq
, chip
);
601 __set_irq_handler(irq
, handle
, 0, NULL
);
605 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
606 irq_flow_handler_t handle
, const char *name
)
608 set_irq_chip(irq
, chip
);
609 __set_irq_handler(irq
, handle
, 0, name
);
612 void __init
set_irq_noprobe(unsigned int irq
)
614 struct irq_desc
*desc
= irq_to_desc(irq
);
618 printk(KERN_ERR
"Trying to mark IRQ%d non-probeable\n", irq
);
622 spin_lock_irqsave(&desc
->lock
, flags
);
623 desc
->status
|= IRQ_NOPROBE
;
624 spin_unlock_irqrestore(&desc
->lock
, flags
);
627 void __init
set_irq_probe(unsigned int irq
)
629 struct irq_desc
*desc
= irq_to_desc(irq
);
633 printk(KERN_ERR
"Trying to mark IRQ%d probeable\n", irq
);
637 spin_lock_irqsave(&desc
->lock
, flags
);
638 desc
->status
&= ~IRQ_NOPROBE
;
639 spin_unlock_irqrestore(&desc
->lock
, flags
);