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
;
63 desc
= __irq_to_desc(irq
);
65 WARN(1, KERN_ERR
"Trying to cleanup invalid IRQ%d\n", irq
);
69 spin_lock_irqsave(&desc
->lock
, flags
);
71 spin_unlock_irqrestore(&desc
->lock
, flags
);
72 WARN(1, KERN_ERR
"Destroying IRQ%d without calling free_irq\n",
76 desc
->msi_desc
= NULL
;
77 desc
->handler_data
= NULL
;
78 desc
->chip_data
= NULL
;
79 desc
->handle_irq
= handle_bad_irq
;
80 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
;
95 desc
= __irq_to_desc(irq
);
97 WARN(1, KERN_ERR
"Trying to install chip for IRQ%d\n", irq
);
104 desc
= irq_to_desc(irq
);
105 spin_lock_irqsave(&desc
->lock
, flags
);
106 irq_chip_set_defaults(chip
);
108 spin_unlock_irqrestore(&desc
->lock
, flags
);
112 EXPORT_SYMBOL(set_irq_chip
);
115 * set_irq_type - set the irq trigger type for an irq
117 * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
119 int set_irq_type(unsigned int irq
, unsigned int type
)
121 struct irq_desc
*desc
;
125 desc
= __irq_to_desc(irq
);
127 printk(KERN_ERR
"Trying to set irq type for IRQ%d\n", irq
);
131 if (type
== IRQ_TYPE_NONE
)
134 spin_lock_irqsave(&desc
->lock
, flags
);
135 ret
= __irq_set_trigger(desc
, irq
, flags
);
136 spin_unlock_irqrestore(&desc
->lock
, flags
);
139 EXPORT_SYMBOL(set_irq_type
);
142 * set_irq_data - set irq type data for an irq
143 * @irq: Interrupt number
144 * @data: Pointer to interrupt specific data
146 * Set the hardware irq controller data for an irq
148 int set_irq_data(unsigned int irq
, void *data
)
150 struct irq_desc
*desc
;
153 desc
= __irq_to_desc(irq
);
156 "Trying to install controller data for IRQ%d\n", irq
);
160 spin_lock_irqsave(&desc
->lock
, flags
);
161 desc
->handler_data
= data
;
162 spin_unlock_irqrestore(&desc
->lock
, flags
);
165 EXPORT_SYMBOL(set_irq_data
);
168 * set_irq_data - set irq type data for an irq
169 * @irq: Interrupt number
170 * @entry: Pointer to MSI descriptor data
172 * Set the hardware irq controller data for an irq
174 int set_irq_msi(unsigned int irq
, struct msi_desc
*entry
)
176 struct irq_desc
*desc
;
179 desc
= __irq_to_desc(irq
);
182 "Trying to install msi data for IRQ%d\n", irq
);
186 spin_lock_irqsave(&desc
->lock
, flags
);
187 desc
->msi_desc
= entry
;
190 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
;
206 desc
= __irq_to_desc(irq
);
209 "Trying to install chip data for IRQ%d\n", irq
);
214 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
218 spin_lock_irqsave(&desc
->lock
, flags
);
219 desc
->chip_data
= data
;
220 spin_unlock_irqrestore(&desc
->lock
, flags
);
224 EXPORT_SYMBOL(set_irq_chip_data
);
227 * default enable function
229 static void default_enable(unsigned int irq
)
231 struct irq_desc
*desc
;
233 desc
= irq_to_desc(irq
);
234 desc
->chip
->unmask(irq
);
235 desc
->status
&= ~IRQ_MASKED
;
239 * default disable function
241 static void default_disable(unsigned int irq
)
246 * default startup function
248 static unsigned int default_startup(unsigned int irq
)
250 struct irq_desc
*desc
;
252 desc
= irq_to_desc(irq
);
253 desc
->chip
->enable(irq
);
259 * default shutdown function
261 static void default_shutdown(unsigned int irq
)
263 struct irq_desc
*desc
;
265 desc
= irq_to_desc(irq
);
266 desc
->chip
->mask(irq
);
267 desc
->status
|= IRQ_MASKED
;
271 * Fixup enable/disable function pointers
273 void irq_chip_set_defaults(struct irq_chip
*chip
)
276 chip
->enable
= default_enable
;
278 chip
->disable
= default_disable
;
280 chip
->startup
= default_startup
;
282 * We use chip->disable, when the user provided its own. When
283 * we have default_disable set for chip->disable, then we need
284 * to use default_shutdown, otherwise the irq line is not
285 * disabled on free_irq():
288 chip
->shutdown
= chip
->disable
!= default_disable
?
289 chip
->disable
: default_shutdown
;
291 chip
->name
= chip
->typename
;
293 chip
->end
= dummy_irq_chip
.end
;
296 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
298 if (desc
->chip
->mask_ack
)
299 desc
->chip
->mask_ack(irq
);
301 desc
->chip
->mask(irq
);
302 desc
->chip
->ack(irq
);
307 * handle_simple_irq - Simple and software-decoded IRQs.
308 * @irq: the interrupt number
309 * @desc: the interrupt description structure for this irq
311 * Simple interrupts are either sent from a demultiplexing interrupt
312 * handler or come from hardware, where no interrupt hardware control
315 * Note: The caller is expected to handle the ack, clear, mask and
316 * unmask issues if necessary.
319 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
321 struct irqaction
*action
;
322 irqreturn_t action_ret
;
324 spin_lock(&desc
->lock
);
326 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
328 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
329 kstat_irqs_this_cpu(desc
)++;
331 action
= desc
->action
;
332 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
335 desc
->status
|= IRQ_INPROGRESS
;
336 spin_unlock(&desc
->lock
);
338 action_ret
= handle_IRQ_event(irq
, action
);
340 note_interrupt(irq
, desc
, action_ret
);
342 spin_lock(&desc
->lock
);
343 desc
->status
&= ~IRQ_INPROGRESS
;
345 spin_unlock(&desc
->lock
);
349 * handle_level_irq - Level type irq handler
350 * @irq: the interrupt number
351 * @desc: the interrupt description structure for this irq
353 * Level type interrupts are active as long as the hardware line has
354 * the active level. This may require to mask the interrupt and unmask
355 * it after the associated handler has acknowledged the device, so the
356 * interrupt line is back to inactive.
359 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
361 struct irqaction
*action
;
362 irqreturn_t action_ret
;
364 spin_lock(&desc
->lock
);
365 mask_ack_irq(desc
, irq
);
367 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
369 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
370 kstat_irqs_this_cpu(desc
)++;
373 * If its disabled or no action available
374 * keep it masked and get out of here
376 action
= desc
->action
;
377 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
380 desc
->status
|= IRQ_INPROGRESS
;
381 spin_unlock(&desc
->lock
);
383 action_ret
= handle_IRQ_event(irq
, action
);
385 note_interrupt(irq
, desc
, action_ret
);
387 spin_lock(&desc
->lock
);
388 desc
->status
&= ~IRQ_INPROGRESS
;
389 if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
390 desc
->chip
->unmask(irq
);
392 spin_unlock(&desc
->lock
);
396 * handle_fasteoi_irq - irq handler for transparent controllers
397 * @irq: the interrupt number
398 * @desc: the interrupt description structure for this irq
400 * Only a single callback will be issued to the chip: an ->eoi()
401 * call when the interrupt has been serviced. This enables support
402 * for modern forms of interrupt handlers, which handle the flow
403 * details in hardware, transparently.
406 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
408 struct irqaction
*action
;
409 irqreturn_t action_ret
;
411 spin_lock(&desc
->lock
);
413 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
416 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
417 kstat_irqs_this_cpu(desc
)++;
420 * If its disabled or no action available
421 * then mask it and get out of here:
423 action
= desc
->action
;
424 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
425 desc
->status
|= IRQ_PENDING
;
426 if (desc
->chip
->mask
)
427 desc
->chip
->mask(irq
);
431 desc
->status
|= IRQ_INPROGRESS
;
432 desc
->status
&= ~IRQ_PENDING
;
433 spin_unlock(&desc
->lock
);
435 action_ret
= handle_IRQ_event(irq
, action
);
437 note_interrupt(irq
, desc
, action_ret
);
439 spin_lock(&desc
->lock
);
440 desc
->status
&= ~IRQ_INPROGRESS
;
442 desc
->chip
->eoi(irq
);
444 spin_unlock(&desc
->lock
);
448 * handle_edge_irq - edge type IRQ handler
449 * @irq: the interrupt number
450 * @desc: the interrupt description structure for this irq
452 * Interrupt occures on the falling and/or rising edge of a hardware
453 * signal. The occurence is latched into the irq controller hardware
454 * and must be acked in order to be reenabled. After the ack another
455 * interrupt can happen on the same source even before the first one
456 * is handled by the assosiacted event handler. If this happens it
457 * might be necessary to disable (mask) the interrupt depending on the
458 * controller hardware. This requires to reenable the interrupt inside
459 * of the loop which handles the interrupts which have arrived while
460 * the handler was running. If all pending interrupts are handled, the
464 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
466 spin_lock(&desc
->lock
);
468 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
471 * If we're currently running this IRQ, or its disabled,
472 * we shouldn't process the IRQ. Mark it pending, handle
473 * the necessary masking and go out
475 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
477 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
478 mask_ack_irq(desc
, irq
);
482 kstat_irqs_this_cpu(desc
)++;
484 /* Start handling the irq */
485 desc
->chip
->ack(irq
);
487 /* Mark the IRQ currently in progress.*/
488 desc
->status
|= IRQ_INPROGRESS
;
491 struct irqaction
*action
= desc
->action
;
492 irqreturn_t action_ret
;
494 if (unlikely(!action
)) {
495 desc
->chip
->mask(irq
);
500 * When another irq arrived while we were handling
501 * one, we could have masked the irq.
502 * Renable it, if it was not disabled in meantime.
504 if (unlikely((desc
->status
&
505 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
506 (IRQ_PENDING
| IRQ_MASKED
))) {
507 desc
->chip
->unmask(irq
);
508 desc
->status
&= ~IRQ_MASKED
;
511 desc
->status
&= ~IRQ_PENDING
;
512 spin_unlock(&desc
->lock
);
513 action_ret
= handle_IRQ_event(irq
, action
);
515 note_interrupt(irq
, desc
, action_ret
);
516 spin_lock(&desc
->lock
);
518 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
520 desc
->status
&= ~IRQ_INPROGRESS
;
522 spin_unlock(&desc
->lock
);
526 * handle_percpu_IRQ - Per CPU local irq handler
527 * @irq: the interrupt number
528 * @desc: the interrupt description structure for this irq
530 * Per CPU interrupts on SMP machines without locking requirements
533 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
535 irqreturn_t action_ret
;
537 kstat_irqs_this_cpu(desc
)++;
540 desc
->chip
->ack(irq
);
542 action_ret
= handle_IRQ_event(irq
, desc
->action
);
544 note_interrupt(irq
, desc
, action_ret
);
547 desc
->chip
->eoi(irq
);
551 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
554 struct irq_desc
*desc
;
557 desc
= __irq_to_desc(irq
);
560 "Trying to install type control for IRQ%d\n", irq
);
565 handle
= handle_bad_irq
;
566 else if (desc
->chip
== &no_irq_chip
) {
567 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
568 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
570 * Some ARM implementations install a handler for really dumb
571 * interrupt hardware without setting an irq_chip. This worked
572 * with the ARM no_irq_chip but the check in setup_irq would
573 * prevent us to setup the interrupt at all. Switch it to
574 * dummy_irq_chip for easy transition.
576 desc
->chip
= &dummy_irq_chip
;
579 spin_lock_irqsave(&desc
->lock
, flags
);
582 if (handle
== handle_bad_irq
) {
583 if (desc
->chip
!= &no_irq_chip
)
584 mask_ack_irq(desc
, irq
);
585 desc
->status
|= IRQ_DISABLED
;
588 desc
->handle_irq
= handle
;
591 if (handle
!= handle_bad_irq
&& is_chained
) {
592 desc
->status
&= ~IRQ_DISABLED
;
593 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
595 desc
->chip
->startup(irq
);
597 spin_unlock_irqrestore(&desc
->lock
, flags
);
601 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
602 irq_flow_handler_t handle
)
604 set_irq_chip(irq
, chip
);
605 __set_irq_handler(irq
, handle
, 0, NULL
);
609 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
610 irq_flow_handler_t handle
, const char *name
)
612 set_irq_chip(irq
, chip
);
613 __set_irq_handler(irq
, handle
, 0, name
);
616 void __init
set_irq_noprobe(unsigned int irq
)
618 struct irq_desc
*desc
;
621 desc
= __irq_to_desc(irq
);
623 printk(KERN_ERR
"Trying to mark IRQ%d non-probeable\n", irq
);
628 spin_lock_irqsave(&desc
->lock
, flags
);
629 desc
->status
|= IRQ_NOPROBE
;
630 spin_unlock_irqrestore(&desc
->lock
, flags
);
633 void __init
set_irq_probe(unsigned int irq
)
635 struct irq_desc
*desc
;
638 desc
= __irq_to_desc(irq
);
640 printk(KERN_ERR
"Trying to mark IRQ%d probeable\n", irq
);
645 spin_lock_irqsave(&desc
->lock
, flags
);
646 desc
->status
&= ~IRQ_NOPROBE
;
647 spin_unlock_irqrestore(&desc
->lock
, flags
);