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 cpumask_setall(desc
->affinity
);
50 #ifdef CONFIG_GENERIC_PENDING_IRQ
51 cpumask_clear(desc
->pending_mask
);
54 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 spin_lock_irqsave(&desc
->lock
, flags
);
73 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 spin_unlock_irqrestore(&desc
->lock
, flags
);
89 * set_irq_chip - set the irq chip for an irq
91 * @chip: pointer to irq chip description structure
93 int set_irq_chip(unsigned int irq
, struct irq_chip
*chip
)
95 struct irq_desc
*desc
= irq_to_desc(irq
);
99 WARN(1, KERN_ERR
"Trying to install chip for IRQ%d\n", irq
);
106 spin_lock_irqsave(&desc
->lock
, flags
);
107 irq_chip_set_defaults(chip
);
109 spin_unlock_irqrestore(&desc
->lock
, flags
);
113 EXPORT_SYMBOL(set_irq_chip
);
116 * set_irq_type - set the irq trigger type for an irq
118 * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
120 int set_irq_type(unsigned int irq
, unsigned int type
)
122 struct irq_desc
*desc
= irq_to_desc(irq
);
127 printk(KERN_ERR
"Trying to set irq type for IRQ%d\n", irq
);
131 type
&= IRQ_TYPE_SENSE_MASK
;
132 if (type
== IRQ_TYPE_NONE
)
135 spin_lock_irqsave(&desc
->lock
, flags
);
136 ret
= __irq_set_trigger(desc
, irq
, type
);
137 spin_unlock_irqrestore(&desc
->lock
, flags
);
140 EXPORT_SYMBOL(set_irq_type
);
143 * set_irq_data - set irq type data for an irq
144 * @irq: Interrupt number
145 * @data: Pointer to interrupt specific data
147 * Set the hardware irq controller data for an irq
149 int set_irq_data(unsigned int irq
, void *data
)
151 struct irq_desc
*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
= irq_to_desc(irq
);
181 "Trying to install msi data for IRQ%d\n", irq
);
185 spin_lock_irqsave(&desc
->lock
, flags
);
186 desc
->msi_desc
= entry
;
189 spin_unlock_irqrestore(&desc
->lock
, flags
);
194 * set_irq_chip_data - set irq chip data for an irq
195 * @irq: Interrupt number
196 * @data: Pointer to chip specific data
198 * Set the hardware irq chip data for an irq
200 int set_irq_chip_data(unsigned int irq
, void *data
)
202 struct irq_desc
*desc
= irq_to_desc(irq
);
207 "Trying to install chip data for IRQ%d\n", irq
);
212 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
216 spin_lock_irqsave(&desc
->lock
, flags
);
217 desc
->chip_data
= data
;
218 spin_unlock_irqrestore(&desc
->lock
, flags
);
222 EXPORT_SYMBOL(set_irq_chip_data
);
225 * default enable function
227 static void default_enable(unsigned int irq
)
229 struct irq_desc
*desc
= irq_to_desc(irq
);
231 desc
->chip
->unmask(irq
);
232 desc
->status
&= ~IRQ_MASKED
;
236 * default disable function
238 static void default_disable(unsigned int irq
)
243 * default startup function
245 static unsigned int default_startup(unsigned int irq
)
247 struct irq_desc
*desc
= irq_to_desc(irq
);
249 desc
->chip
->enable(irq
);
254 * default shutdown function
256 static void default_shutdown(unsigned int irq
)
258 struct irq_desc
*desc
= irq_to_desc(irq
);
260 desc
->chip
->mask(irq
);
261 desc
->status
|= IRQ_MASKED
;
265 * Fixup enable/disable function pointers
267 void irq_chip_set_defaults(struct irq_chip
*chip
)
270 chip
->enable
= default_enable
;
272 chip
->disable
= default_disable
;
274 chip
->startup
= default_startup
;
276 * We use chip->disable, when the user provided its own. When
277 * we have default_disable set for chip->disable, then we need
278 * to use default_shutdown, otherwise the irq line is not
279 * disabled on free_irq():
282 chip
->shutdown
= chip
->disable
!= default_disable
?
283 chip
->disable
: default_shutdown
;
285 chip
->name
= chip
->typename
;
287 chip
->end
= dummy_irq_chip
.end
;
290 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
292 if (desc
->chip
->mask_ack
)
293 desc
->chip
->mask_ack(irq
);
295 desc
->chip
->mask(irq
);
296 desc
->chip
->ack(irq
);
301 * handle_simple_irq - Simple and software-decoded IRQs.
302 * @irq: the interrupt number
303 * @desc: the interrupt description structure for this irq
305 * Simple interrupts are either sent from a demultiplexing interrupt
306 * handler or come from hardware, where no interrupt hardware control
309 * Note: The caller is expected to handle the ack, clear, mask and
310 * unmask issues if necessary.
313 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
315 struct irqaction
*action
;
316 irqreturn_t action_ret
;
318 spin_lock(&desc
->lock
);
320 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
322 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
323 kstat_incr_irqs_this_cpu(irq
, desc
);
325 action
= desc
->action
;
326 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
329 desc
->status
|= IRQ_INPROGRESS
;
330 spin_unlock(&desc
->lock
);
332 action_ret
= handle_IRQ_event(irq
, action
);
334 note_interrupt(irq
, desc
, action_ret
);
336 spin_lock(&desc
->lock
);
337 desc
->status
&= ~IRQ_INPROGRESS
;
339 spin_unlock(&desc
->lock
);
343 * handle_level_irq - Level type irq handler
344 * @irq: the interrupt number
345 * @desc: the interrupt description structure for this irq
347 * Level type interrupts are active as long as the hardware line has
348 * the active level. This may require to mask the interrupt and unmask
349 * it after the associated handler has acknowledged the device, so the
350 * interrupt line is back to inactive.
353 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
355 struct irqaction
*action
;
356 irqreturn_t action_ret
;
358 spin_lock(&desc
->lock
);
359 mask_ack_irq(desc
, irq
);
360 desc
= irq_remap_to_desc(irq
, desc
);
362 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
364 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
365 kstat_incr_irqs_this_cpu(irq
, desc
);
368 * If its disabled or no action available
369 * keep it masked and get out of here
371 action
= desc
->action
;
372 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
375 desc
->status
|= IRQ_INPROGRESS
;
376 spin_unlock(&desc
->lock
);
378 action_ret
= handle_IRQ_event(irq
, action
);
380 note_interrupt(irq
, desc
, action_ret
);
382 spin_lock(&desc
->lock
);
383 desc
->status
&= ~IRQ_INPROGRESS
;
384 if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
385 desc
->chip
->unmask(irq
);
387 spin_unlock(&desc
->lock
);
389 EXPORT_SYMBOL_GPL(handle_level_irq
);
392 * handle_fasteoi_irq - irq handler for transparent controllers
393 * @irq: the interrupt number
394 * @desc: the interrupt description structure for this irq
396 * Only a single callback will be issued to the chip: an ->eoi()
397 * call when the interrupt has been serviced. This enables support
398 * for modern forms of interrupt handlers, which handle the flow
399 * details in hardware, transparently.
402 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
404 struct irqaction
*action
;
405 irqreturn_t action_ret
;
407 spin_lock(&desc
->lock
);
409 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
412 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
413 kstat_incr_irqs_this_cpu(irq
, desc
);
416 * If its disabled or no action available
417 * then mask it and get out of here:
419 action
= desc
->action
;
420 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
421 desc
->status
|= IRQ_PENDING
;
422 if (desc
->chip
->mask
)
423 desc
->chip
->mask(irq
);
427 desc
->status
|= IRQ_INPROGRESS
;
428 desc
->status
&= ~IRQ_PENDING
;
429 spin_unlock(&desc
->lock
);
431 action_ret
= handle_IRQ_event(irq
, action
);
433 note_interrupt(irq
, desc
, action_ret
);
435 spin_lock(&desc
->lock
);
436 desc
->status
&= ~IRQ_INPROGRESS
;
438 desc
->chip
->eoi(irq
);
439 desc
= irq_remap_to_desc(irq
, desc
);
441 spin_unlock(&desc
->lock
);
445 * handle_edge_irq - edge type IRQ handler
446 * @irq: the interrupt number
447 * @desc: the interrupt description structure for this irq
449 * Interrupt occures on the falling and/or rising edge of a hardware
450 * signal. The occurence is latched into the irq controller hardware
451 * and must be acked in order to be reenabled. After the ack another
452 * interrupt can happen on the same source even before the first one
453 * is handled by the assosiacted event handler. If this happens it
454 * might be necessary to disable (mask) the interrupt depending on the
455 * controller hardware. This requires to reenable the interrupt inside
456 * of the loop which handles the interrupts which have arrived while
457 * the handler was running. If all pending interrupts are handled, the
461 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
463 spin_lock(&desc
->lock
);
465 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
468 * If we're currently running this IRQ, or its disabled,
469 * we shouldn't process the IRQ. Mark it pending, handle
470 * the necessary masking and go out
472 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
474 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
475 mask_ack_irq(desc
, irq
);
476 desc
= irq_remap_to_desc(irq
, desc
);
479 kstat_incr_irqs_this_cpu(irq
, desc
);
481 /* Start handling the irq */
482 desc
->chip
->ack(irq
);
483 desc
= irq_remap_to_desc(irq
, desc
);
485 /* Mark the IRQ currently in progress.*/
486 desc
->status
|= IRQ_INPROGRESS
;
489 struct irqaction
*action
= desc
->action
;
490 irqreturn_t action_ret
;
492 if (unlikely(!action
)) {
493 desc
->chip
->mask(irq
);
498 * When another irq arrived while we were handling
499 * one, we could have masked the irq.
500 * Renable it, if it was not disabled in meantime.
502 if (unlikely((desc
->status
&
503 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
504 (IRQ_PENDING
| IRQ_MASKED
))) {
505 desc
->chip
->unmask(irq
);
506 desc
->status
&= ~IRQ_MASKED
;
509 desc
->status
&= ~IRQ_PENDING
;
510 spin_unlock(&desc
->lock
);
511 action_ret
= handle_IRQ_event(irq
, action
);
513 note_interrupt(irq
, desc
, action_ret
);
514 spin_lock(&desc
->lock
);
516 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
518 desc
->status
&= ~IRQ_INPROGRESS
;
520 spin_unlock(&desc
->lock
);
524 * handle_percpu_IRQ - Per CPU local irq handler
525 * @irq: the interrupt number
526 * @desc: the interrupt description structure for this irq
528 * Per CPU interrupts on SMP machines without locking requirements
531 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
533 irqreturn_t action_ret
;
535 kstat_incr_irqs_this_cpu(irq
, desc
);
538 desc
->chip
->ack(irq
);
540 action_ret
= handle_IRQ_event(irq
, desc
->action
);
542 note_interrupt(irq
, desc
, action_ret
);
544 if (desc
->chip
->eoi
) {
545 desc
->chip
->eoi(irq
);
546 desc
= irq_remap_to_desc(irq
, desc
);
551 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
554 struct irq_desc
*desc
= irq_to_desc(irq
);
559 "Trying to install type control for IRQ%d\n", irq
);
564 handle
= handle_bad_irq
;
565 else if (desc
->chip
== &no_irq_chip
) {
566 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
567 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
569 * Some ARM implementations install a handler for really dumb
570 * interrupt hardware without setting an irq_chip. This worked
571 * with the ARM no_irq_chip but the check in setup_irq would
572 * prevent us to setup the interrupt at all. Switch it to
573 * dummy_irq_chip for easy transition.
575 desc
->chip
= &dummy_irq_chip
;
578 spin_lock_irqsave(&desc
->lock
, flags
);
581 if (handle
== handle_bad_irq
) {
582 if (desc
->chip
!= &no_irq_chip
) {
583 mask_ack_irq(desc
, irq
);
584 desc
= irq_remap_to_desc(irq
, desc
);
586 desc
->status
|= IRQ_DISABLED
;
589 desc
->handle_irq
= handle
;
592 if (handle
!= handle_bad_irq
&& is_chained
) {
593 desc
->status
&= ~IRQ_DISABLED
;
594 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
596 desc
->chip
->startup(irq
);
598 spin_unlock_irqrestore(&desc
->lock
, flags
);
600 EXPORT_SYMBOL_GPL(__set_irq_handler
);
603 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
604 irq_flow_handler_t handle
)
606 set_irq_chip(irq
, chip
);
607 __set_irq_handler(irq
, handle
, 0, NULL
);
611 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
612 irq_flow_handler_t handle
, const char *name
)
614 set_irq_chip(irq
, chip
);
615 __set_irq_handler(irq
, handle
, 0, name
);
618 void __init
set_irq_noprobe(unsigned int irq
)
620 struct irq_desc
*desc
= irq_to_desc(irq
);
624 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
= irq_to_desc(irq
);
639 printk(KERN_ERR
"Trying to mark IRQ%d probeable\n", irq
);
643 spin_lock_irqsave(&desc
->lock
, flags
);
644 desc
->status
&= ~IRQ_NOPROBE
;
645 spin_unlock_irqrestore(&desc
->lock
, flags
);