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
);
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 type
&= IRQ_TYPE_SENSE_MASK
;
129 if (type
== IRQ_TYPE_NONE
)
132 spin_lock_irqsave(&desc
->lock
, flags
);
133 ret
= __irq_set_trigger(desc
, irq
, type
);
134 spin_unlock_irqrestore(&desc
->lock
, flags
);
137 EXPORT_SYMBOL(set_irq_type
);
140 * set_irq_data - set irq type data for an irq
141 * @irq: Interrupt number
142 * @data: Pointer to interrupt specific data
144 * Set the hardware irq controller data for an irq
146 int set_irq_data(unsigned int irq
, void *data
)
148 struct irq_desc
*desc
= irq_to_desc(irq
);
153 "Trying to install controller data for IRQ%d\n", irq
);
157 spin_lock_irqsave(&desc
->lock
, flags
);
158 desc
->handler_data
= data
;
159 spin_unlock_irqrestore(&desc
->lock
, flags
);
162 EXPORT_SYMBOL(set_irq_data
);
165 * set_irq_data - set irq type data for an irq
166 * @irq: Interrupt number
167 * @entry: Pointer to MSI descriptor data
169 * Set the hardware irq controller data for an irq
171 int set_irq_msi(unsigned int irq
, struct msi_desc
*entry
)
173 struct irq_desc
*desc
= irq_to_desc(irq
);
178 "Trying to install msi data for IRQ%d\n", irq
);
182 spin_lock_irqsave(&desc
->lock
, flags
);
183 desc
->msi_desc
= entry
;
186 spin_unlock_irqrestore(&desc
->lock
, flags
);
191 * set_irq_chip_data - set irq chip data for an irq
192 * @irq: Interrupt number
193 * @data: Pointer to chip specific data
195 * Set the hardware irq chip data for an irq
197 int set_irq_chip_data(unsigned int irq
, void *data
)
199 struct irq_desc
*desc
= irq_to_desc(irq
);
204 "Trying to install chip data for IRQ%d\n", irq
);
209 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
213 spin_lock_irqsave(&desc
->lock
, flags
);
214 desc
->chip_data
= data
;
215 spin_unlock_irqrestore(&desc
->lock
, flags
);
219 EXPORT_SYMBOL(set_irq_chip_data
);
222 * default enable function
224 static void default_enable(unsigned int irq
)
226 struct irq_desc
*desc
= irq_to_desc(irq
);
228 desc
->chip
->unmask(irq
);
229 desc
->status
&= ~IRQ_MASKED
;
233 * default disable function
235 static void default_disable(unsigned int irq
)
240 * default startup function
242 static unsigned int default_startup(unsigned int irq
)
244 struct irq_desc
*desc
= irq_to_desc(irq
);
246 desc
->chip
->enable(irq
);
251 * default shutdown function
253 static void default_shutdown(unsigned int irq
)
255 struct irq_desc
*desc
= irq_to_desc(irq
);
257 desc
->chip
->mask(irq
);
258 desc
->status
|= IRQ_MASKED
;
262 * Fixup enable/disable function pointers
264 void irq_chip_set_defaults(struct irq_chip
*chip
)
267 chip
->enable
= default_enable
;
269 chip
->disable
= default_disable
;
271 chip
->startup
= default_startup
;
273 * We use chip->disable, when the user provided its own. When
274 * we have default_disable set for chip->disable, then we need
275 * to use default_shutdown, otherwise the irq line is not
276 * disabled on free_irq():
279 chip
->shutdown
= chip
->disable
!= default_disable
?
280 chip
->disable
: default_shutdown
;
282 chip
->name
= chip
->typename
;
284 chip
->end
= dummy_irq_chip
.end
;
287 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
289 if (desc
->chip
->mask_ack
)
290 desc
->chip
->mask_ack(irq
);
292 desc
->chip
->mask(irq
);
293 desc
->chip
->ack(irq
);
298 * handle_simple_irq - Simple and software-decoded IRQs.
299 * @irq: the interrupt number
300 * @desc: the interrupt description structure for this irq
302 * Simple interrupts are either sent from a demultiplexing interrupt
303 * handler or come from hardware, where no interrupt hardware control
306 * Note: The caller is expected to handle the ack, clear, mask and
307 * unmask issues if necessary.
310 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
312 struct irqaction
*action
;
313 irqreturn_t action_ret
;
315 spin_lock(&desc
->lock
);
317 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
319 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
320 kstat_incr_irqs_this_cpu(irq
, desc
);
322 action
= desc
->action
;
323 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
326 desc
->status
|= IRQ_INPROGRESS
;
327 spin_unlock(&desc
->lock
);
329 action_ret
= handle_IRQ_event(irq
, action
);
331 note_interrupt(irq
, desc
, action_ret
);
333 spin_lock(&desc
->lock
);
334 desc
->status
&= ~IRQ_INPROGRESS
;
336 spin_unlock(&desc
->lock
);
340 * handle_level_irq - Level type irq handler
341 * @irq: the interrupt number
342 * @desc: the interrupt description structure for this irq
344 * Level type interrupts are active as long as the hardware line has
345 * the active level. This may require to mask the interrupt and unmask
346 * it after the associated handler has acknowledged the device, so the
347 * interrupt line is back to inactive.
350 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
352 struct irqaction
*action
;
353 irqreturn_t action_ret
;
355 spin_lock(&desc
->lock
);
356 mask_ack_irq(desc
, irq
);
357 desc
= irq_remap_to_desc(irq
, desc
);
359 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
361 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
362 kstat_incr_irqs_this_cpu(irq
, desc
);
365 * If its disabled or no action available
366 * keep it masked and get out of here
368 action
= desc
->action
;
369 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
)))
372 desc
->status
|= IRQ_INPROGRESS
;
373 spin_unlock(&desc
->lock
);
375 action_ret
= handle_IRQ_event(irq
, action
);
377 note_interrupt(irq
, desc
, action_ret
);
379 spin_lock(&desc
->lock
);
380 desc
->status
&= ~IRQ_INPROGRESS
;
381 if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
382 desc
->chip
->unmask(irq
);
384 spin_unlock(&desc
->lock
);
388 * handle_fasteoi_irq - irq handler for transparent controllers
389 * @irq: the interrupt number
390 * @desc: the interrupt description structure for this irq
392 * Only a single callback will be issued to the chip: an ->eoi()
393 * call when the interrupt has been serviced. This enables support
394 * for modern forms of interrupt handlers, which handle the flow
395 * details in hardware, transparently.
398 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
400 struct irqaction
*action
;
401 irqreturn_t action_ret
;
403 spin_lock(&desc
->lock
);
405 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
408 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
409 kstat_incr_irqs_this_cpu(irq
, desc
);
412 * If its disabled or no action available
413 * then mask it and get out of here:
415 action
= desc
->action
;
416 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
417 desc
->status
|= IRQ_PENDING
;
418 if (desc
->chip
->mask
)
419 desc
->chip
->mask(irq
);
423 desc
->status
|= IRQ_INPROGRESS
;
424 desc
->status
&= ~IRQ_PENDING
;
425 spin_unlock(&desc
->lock
);
427 action_ret
= handle_IRQ_event(irq
, action
);
429 note_interrupt(irq
, desc
, action_ret
);
431 spin_lock(&desc
->lock
);
432 desc
->status
&= ~IRQ_INPROGRESS
;
434 desc
->chip
->eoi(irq
);
435 desc
= irq_remap_to_desc(irq
, desc
);
437 spin_unlock(&desc
->lock
);
441 * handle_edge_irq - edge type IRQ handler
442 * @irq: the interrupt number
443 * @desc: the interrupt description structure for this irq
445 * Interrupt occures on the falling and/or rising edge of a hardware
446 * signal. The occurence is latched into the irq controller hardware
447 * and must be acked in order to be reenabled. After the ack another
448 * interrupt can happen on the same source even before the first one
449 * is handled by the assosiacted event handler. If this happens it
450 * might be necessary to disable (mask) the interrupt depending on the
451 * controller hardware. This requires to reenable the interrupt inside
452 * of the loop which handles the interrupts which have arrived while
453 * the handler was running. If all pending interrupts are handled, the
457 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
459 spin_lock(&desc
->lock
);
461 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
464 * If we're currently running this IRQ, or its disabled,
465 * we shouldn't process the IRQ. Mark it pending, handle
466 * the necessary masking and go out
468 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
470 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
471 mask_ack_irq(desc
, irq
);
472 desc
= irq_remap_to_desc(irq
, desc
);
475 kstat_incr_irqs_this_cpu(irq
, desc
);
477 /* Start handling the irq */
478 desc
->chip
->ack(irq
);
479 desc
= irq_remap_to_desc(irq
, desc
);
481 /* Mark the IRQ currently in progress.*/
482 desc
->status
|= IRQ_INPROGRESS
;
485 struct irqaction
*action
= desc
->action
;
486 irqreturn_t action_ret
;
488 if (unlikely(!action
)) {
489 desc
->chip
->mask(irq
);
494 * When another irq arrived while we were handling
495 * one, we could have masked the irq.
496 * Renable it, if it was not disabled in meantime.
498 if (unlikely((desc
->status
&
499 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
500 (IRQ_PENDING
| IRQ_MASKED
))) {
501 desc
->chip
->unmask(irq
);
502 desc
->status
&= ~IRQ_MASKED
;
505 desc
->status
&= ~IRQ_PENDING
;
506 spin_unlock(&desc
->lock
);
507 action_ret
= handle_IRQ_event(irq
, action
);
509 note_interrupt(irq
, desc
, action_ret
);
510 spin_lock(&desc
->lock
);
512 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
514 desc
->status
&= ~IRQ_INPROGRESS
;
516 spin_unlock(&desc
->lock
);
520 * handle_percpu_IRQ - Per CPU local irq handler
521 * @irq: the interrupt number
522 * @desc: the interrupt description structure for this irq
524 * Per CPU interrupts on SMP machines without locking requirements
527 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
529 irqreturn_t action_ret
;
531 kstat_incr_irqs_this_cpu(irq
, desc
);
534 desc
->chip
->ack(irq
);
536 action_ret
= handle_IRQ_event(irq
, desc
->action
);
538 note_interrupt(irq
, desc
, action_ret
);
540 if (desc
->chip
->eoi
) {
541 desc
->chip
->eoi(irq
);
542 desc
= irq_remap_to_desc(irq
, desc
);
547 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
550 struct irq_desc
*desc
= irq_to_desc(irq
);
555 "Trying to install type control for IRQ%d\n", irq
);
560 handle
= handle_bad_irq
;
561 else if (desc
->chip
== &no_irq_chip
) {
562 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
563 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
565 * Some ARM implementations install a handler for really dumb
566 * interrupt hardware without setting an irq_chip. This worked
567 * with the ARM no_irq_chip but the check in setup_irq would
568 * prevent us to setup the interrupt at all. Switch it to
569 * dummy_irq_chip for easy transition.
571 desc
->chip
= &dummy_irq_chip
;
574 spin_lock_irqsave(&desc
->lock
, flags
);
577 if (handle
== handle_bad_irq
) {
578 if (desc
->chip
!= &no_irq_chip
) {
579 mask_ack_irq(desc
, irq
);
580 desc
= irq_remap_to_desc(irq
, desc
);
582 desc
->status
|= IRQ_DISABLED
;
585 desc
->handle_irq
= handle
;
588 if (handle
!= handle_bad_irq
&& is_chained
) {
589 desc
->status
&= ~IRQ_DISABLED
;
590 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
592 desc
->chip
->startup(irq
);
594 spin_unlock_irqrestore(&desc
->lock
, flags
);
598 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
599 irq_flow_handler_t handle
)
601 set_irq_chip(irq
, chip
);
602 __set_irq_handler(irq
, handle
, 0, NULL
);
606 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
607 irq_flow_handler_t handle
, const char *name
)
609 set_irq_chip(irq
, chip
);
610 __set_irq_handler(irq
, handle
, 0, name
);
613 void __init
set_irq_noprobe(unsigned int irq
)
615 struct irq_desc
*desc
= irq_to_desc(irq
);
619 printk(KERN_ERR
"Trying to mark IRQ%d non-probeable\n", irq
);
623 spin_lock_irqsave(&desc
->lock
, flags
);
624 desc
->status
|= IRQ_NOPROBE
;
625 spin_unlock_irqrestore(&desc
->lock
, flags
);
628 void __init
set_irq_probe(unsigned int irq
)
630 struct irq_desc
*desc
= irq_to_desc(irq
);
634 printk(KERN_ERR
"Trying to mark IRQ%d probeable\n", irq
);
638 spin_lock_irqsave(&desc
->lock
, flags
);
639 desc
->status
&= ~IRQ_NOPROBE
;
640 spin_unlock_irqrestore(&desc
->lock
, flags
);