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/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel_stat.h>
18 #include "internals.h"
21 * dynamic_irq_init - initialize a dynamically allocated irq
22 * @irq: irq number to initialize
24 void dynamic_irq_init(unsigned int irq
)
26 struct irq_desc
*desc
;
30 printk(KERN_ERR
"Trying to initialize invalid IRQ%d\n", irq
);
35 /* Ensure we don't have left over values from a previous use of this irq */
36 desc
= irq_desc
+ 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 desc
->affinity
= CPU_MASK_ALL
;
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
;
64 printk(KERN_ERR
"Trying to cleanup invalid IRQ%d\n", irq
);
69 desc
= irq_desc
+ irq
;
70 spin_lock_irqsave(&desc
->lock
, flags
);
72 spin_unlock_irqrestore(&desc
->lock
, flags
);
73 printk(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
;
83 spin_unlock_irqrestore(&desc
->lock
, flags
);
88 * set_irq_chip - set the irq chip for an irq
90 * @chip: pointer to irq chip description structure
92 int set_irq_chip(unsigned int irq
, struct irq_chip
*chip
)
94 struct irq_desc
*desc
;
98 printk(KERN_ERR
"Trying to install chip for IRQ%d\n", irq
);
106 desc
= irq_desc
+ irq
;
107 spin_lock_irqsave(&desc
->lock
, flags
);
108 irq_chip_set_defaults(chip
);
110 spin_unlock_irqrestore(&desc
->lock
, flags
);
114 EXPORT_SYMBOL(set_irq_chip
);
117 * set_irq_type - set the irq type for an irq
119 * @type: interrupt type - see include/linux/interrupt.h
121 int set_irq_type(unsigned int irq
, unsigned int type
)
123 struct irq_desc
*desc
;
127 if (irq
>= NR_IRQS
) {
128 printk(KERN_ERR
"Trying to set irq type for IRQ%d\n", irq
);
132 desc
= irq_desc
+ irq
;
133 if (desc
->chip
->set_type
) {
134 spin_lock_irqsave(&desc
->lock
, flags
);
135 ret
= desc
->chip
->set_type(irq
, type
);
136 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
;
154 if (irq
>= NR_IRQS
) {
156 "Trying to install controller data for IRQ%d\n", irq
);
160 desc
= irq_desc
+ irq
;
161 spin_lock_irqsave(&desc
->lock
, flags
);
162 desc
->handler_data
= data
;
163 spin_unlock_irqrestore(&desc
->lock
, flags
);
166 EXPORT_SYMBOL(set_irq_data
);
169 * set_irq_data - set irq type data for an irq
170 * @irq: Interrupt number
171 * @entry: Pointer to MSI descriptor data
173 * Set the hardware irq controller data for an irq
175 int set_irq_msi(unsigned int irq
, struct msi_desc
*entry
)
177 struct irq_desc
*desc
;
180 if (irq
>= NR_IRQS
) {
182 "Trying to install msi data for IRQ%d\n", irq
);
185 desc
= irq_desc
+ irq
;
186 spin_lock_irqsave(&desc
->lock
, flags
);
187 desc
->msi_desc
= entry
;
188 spin_unlock_irqrestore(&desc
->lock
, flags
);
193 * set_irq_chip_data - set irq chip data for an irq
194 * @irq: Interrupt number
195 * @data: Pointer to chip specific data
197 * Set the hardware irq chip data for an irq
199 int set_irq_chip_data(unsigned int irq
, void *data
)
201 struct irq_desc
*desc
= irq_desc
+ irq
;
204 if (irq
>= NR_IRQS
|| !desc
->chip
) {
205 printk(KERN_ERR
"BUG: bad set_irq_chip_data(IRQ#%d)\n", irq
);
209 spin_lock_irqsave(&desc
->lock
, flags
);
210 desc
->chip_data
= data
;
211 spin_unlock_irqrestore(&desc
->lock
, flags
);
215 EXPORT_SYMBOL(set_irq_chip_data
);
218 * default enable function
220 static void default_enable(unsigned int irq
)
222 struct irq_desc
*desc
= irq_desc
+ irq
;
224 desc
->chip
->unmask(irq
);
225 desc
->status
&= ~IRQ_MASKED
;
229 * default disable function
231 static void default_disable(unsigned int irq
)
236 * default startup function
238 static unsigned int default_startup(unsigned int irq
)
240 irq_desc
[irq
].chip
->enable(irq
);
246 * Fixup enable/disable function pointers
248 void irq_chip_set_defaults(struct irq_chip
*chip
)
251 chip
->enable
= default_enable
;
253 chip
->disable
= default_disable
;
255 chip
->startup
= default_startup
;
257 chip
->shutdown
= chip
->disable
;
259 chip
->name
= chip
->typename
;
261 chip
->end
= dummy_irq_chip
.end
;
264 static inline void mask_ack_irq(struct irq_desc
*desc
, int irq
)
266 if (desc
->chip
->mask_ack
)
267 desc
->chip
->mask_ack(irq
);
269 desc
->chip
->mask(irq
);
270 desc
->chip
->ack(irq
);
275 * handle_simple_irq - Simple and software-decoded IRQs.
276 * @irq: the interrupt number
277 * @desc: the interrupt description structure for this irq
279 * Simple interrupts are either sent from a demultiplexing interrupt
280 * handler or come from hardware, where no interrupt hardware control
283 * Note: The caller is expected to handle the ack, clear, mask and
284 * unmask issues if necessary.
287 handle_simple_irq(unsigned int irq
, struct irq_desc
*desc
)
289 struct irqaction
*action
;
290 irqreturn_t action_ret
;
291 const unsigned int cpu
= smp_processor_id();
293 spin_lock(&desc
->lock
);
295 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
297 kstat_cpu(cpu
).irqs
[irq
]++;
299 action
= desc
->action
;
300 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
301 if (desc
->chip
->mask
)
302 desc
->chip
->mask(irq
);
303 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
304 desc
->status
|= IRQ_PENDING
;
308 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
| IRQ_PENDING
);
309 desc
->status
|= IRQ_INPROGRESS
;
310 spin_unlock(&desc
->lock
);
312 action_ret
= handle_IRQ_event(irq
, action
);
314 note_interrupt(irq
, desc
, action_ret
);
316 spin_lock(&desc
->lock
);
317 desc
->status
&= ~IRQ_INPROGRESS
;
319 spin_unlock(&desc
->lock
);
323 * handle_level_irq - Level type irq handler
324 * @irq: the interrupt number
325 * @desc: the interrupt description structure for this irq
327 * Level type interrupts are active as long as the hardware line has
328 * the active level. This may require to mask the interrupt and unmask
329 * it after the associated handler has acknowledged the device, so the
330 * interrupt line is back to inactive.
333 handle_level_irq(unsigned int irq
, struct irq_desc
*desc
)
335 unsigned int cpu
= smp_processor_id();
336 struct irqaction
*action
;
337 irqreturn_t action_ret
;
339 spin_lock(&desc
->lock
);
340 mask_ack_irq(desc
, irq
);
342 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
344 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
345 kstat_cpu(cpu
).irqs
[irq
]++;
348 * If its disabled or no action available
349 * keep it masked and get out of here
351 action
= desc
->action
;
352 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
353 desc
->status
|= IRQ_PENDING
;
357 desc
->status
|= IRQ_INPROGRESS
;
358 desc
->status
&= ~IRQ_PENDING
;
359 spin_unlock(&desc
->lock
);
361 action_ret
= handle_IRQ_event(irq
, action
);
363 note_interrupt(irq
, desc
, action_ret
);
365 spin_lock(&desc
->lock
);
366 desc
->status
&= ~IRQ_INPROGRESS
;
367 if (!(desc
->status
& IRQ_DISABLED
) && desc
->chip
->unmask
)
368 desc
->chip
->unmask(irq
);
370 spin_unlock(&desc
->lock
);
374 * handle_fasteoi_irq - irq handler for transparent controllers
375 * @irq: the interrupt number
376 * @desc: the interrupt description structure for this irq
378 * Only a single callback will be issued to the chip: an ->eoi()
379 * call when the interrupt has been serviced. This enables support
380 * for modern forms of interrupt handlers, which handle the flow
381 * details in hardware, transparently.
384 handle_fasteoi_irq(unsigned int irq
, struct irq_desc
*desc
)
386 unsigned int cpu
= smp_processor_id();
387 struct irqaction
*action
;
388 irqreturn_t action_ret
;
390 spin_lock(&desc
->lock
);
392 if (unlikely(desc
->status
& IRQ_INPROGRESS
))
395 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
396 kstat_cpu(cpu
).irqs
[irq
]++;
399 * If its disabled or no action available
400 * then mask it and get out of here:
402 action
= desc
->action
;
403 if (unlikely(!action
|| (desc
->status
& IRQ_DISABLED
))) {
404 desc
->status
|= IRQ_PENDING
;
405 if (desc
->chip
->mask
)
406 desc
->chip
->mask(irq
);
410 desc
->status
|= IRQ_INPROGRESS
;
411 desc
->status
&= ~IRQ_PENDING
;
412 spin_unlock(&desc
->lock
);
414 action_ret
= handle_IRQ_event(irq
, action
);
416 note_interrupt(irq
, desc
, action_ret
);
418 spin_lock(&desc
->lock
);
419 desc
->status
&= ~IRQ_INPROGRESS
;
421 desc
->chip
->eoi(irq
);
423 spin_unlock(&desc
->lock
);
427 * handle_edge_irq - edge type IRQ handler
428 * @irq: the interrupt number
429 * @desc: the interrupt description structure for this irq
431 * Interrupt occures on the falling and/or rising edge of a hardware
432 * signal. The occurence is latched into the irq controller hardware
433 * and must be acked in order to be reenabled. After the ack another
434 * interrupt can happen on the same source even before the first one
435 * is handled by the assosiacted event handler. If this happens it
436 * might be necessary to disable (mask) the interrupt depending on the
437 * controller hardware. This requires to reenable the interrupt inside
438 * of the loop which handles the interrupts which have arrived while
439 * the handler was running. If all pending interrupts are handled, the
443 handle_edge_irq(unsigned int irq
, struct irq_desc
*desc
)
445 const unsigned int cpu
= smp_processor_id();
447 spin_lock(&desc
->lock
);
449 desc
->status
&= ~(IRQ_REPLAY
| IRQ_WAITING
);
452 * If we're currently running this IRQ, or its disabled,
453 * we shouldn't process the IRQ. Mark it pending, handle
454 * the necessary masking and go out
456 if (unlikely((desc
->status
& (IRQ_INPROGRESS
| IRQ_DISABLED
)) ||
458 desc
->status
|= (IRQ_PENDING
| IRQ_MASKED
);
459 mask_ack_irq(desc
, irq
);
463 kstat_cpu(cpu
).irqs
[irq
]++;
465 /* Start handling the irq */
466 desc
->chip
->ack(irq
);
468 /* Mark the IRQ currently in progress.*/
469 desc
->status
|= IRQ_INPROGRESS
;
472 struct irqaction
*action
= desc
->action
;
473 irqreturn_t action_ret
;
475 if (unlikely(!action
)) {
476 desc
->chip
->mask(irq
);
481 * When another irq arrived while we were handling
482 * one, we could have masked the irq.
483 * Renable it, if it was not disabled in meantime.
485 if (unlikely((desc
->status
&
486 (IRQ_PENDING
| IRQ_MASKED
| IRQ_DISABLED
)) ==
487 (IRQ_PENDING
| IRQ_MASKED
))) {
488 desc
->chip
->unmask(irq
);
489 desc
->status
&= ~IRQ_MASKED
;
492 desc
->status
&= ~IRQ_PENDING
;
493 spin_unlock(&desc
->lock
);
494 action_ret
= handle_IRQ_event(irq
, action
);
496 note_interrupt(irq
, desc
, action_ret
);
497 spin_lock(&desc
->lock
);
499 } while ((desc
->status
& (IRQ_PENDING
| IRQ_DISABLED
)) == IRQ_PENDING
);
501 desc
->status
&= ~IRQ_INPROGRESS
;
503 spin_unlock(&desc
->lock
);
508 * handle_percpu_IRQ - Per CPU local irq handler
509 * @irq: the interrupt number
510 * @desc: the interrupt description structure for this irq
512 * Per CPU interrupts on SMP machines without locking requirements
515 handle_percpu_irq(unsigned int irq
, struct irq_desc
*desc
)
517 irqreturn_t action_ret
;
519 kstat_this_cpu
.irqs
[irq
]++;
522 desc
->chip
->ack(irq
);
524 action_ret
= handle_IRQ_event(irq
, desc
->action
);
526 note_interrupt(irq
, desc
, action_ret
);
529 desc
->chip
->eoi(irq
);
532 #endif /* CONFIG_SMP */
535 __set_irq_handler(unsigned int irq
, irq_flow_handler_t handle
, int is_chained
,
538 struct irq_desc
*desc
;
541 if (irq
>= NR_IRQS
) {
543 "Trying to install type control for IRQ%d\n", irq
);
547 desc
= irq_desc
+ irq
;
550 handle
= handle_bad_irq
;
551 else if (desc
->chip
== &no_irq_chip
) {
552 printk(KERN_WARNING
"Trying to install %sinterrupt handler "
553 "for IRQ%d\n", is_chained
? "chained " : "", irq
);
555 * Some ARM implementations install a handler for really dumb
556 * interrupt hardware without setting an irq_chip. This worked
557 * with the ARM no_irq_chip but the check in setup_irq would
558 * prevent us to setup the interrupt at all. Switch it to
559 * dummy_irq_chip for easy transition.
561 desc
->chip
= &dummy_irq_chip
;
564 spin_lock_irqsave(&desc
->lock
, flags
);
567 if (handle
== handle_bad_irq
) {
568 if (desc
->chip
!= &no_irq_chip
)
569 mask_ack_irq(desc
, irq
);
570 desc
->status
|= IRQ_DISABLED
;
573 desc
->handle_irq
= handle
;
576 if (handle
!= handle_bad_irq
&& is_chained
) {
577 desc
->status
&= ~IRQ_DISABLED
;
578 desc
->status
|= IRQ_NOREQUEST
| IRQ_NOPROBE
;
580 desc
->chip
->unmask(irq
);
582 spin_unlock_irqrestore(&desc
->lock
, flags
);
586 set_irq_chip_and_handler(unsigned int irq
, struct irq_chip
*chip
,
587 irq_flow_handler_t handle
)
589 set_irq_chip(irq
, chip
);
590 __set_irq_handler(irq
, handle
, 0, NULL
);
594 set_irq_chip_and_handler_name(unsigned int irq
, struct irq_chip
*chip
,
595 irq_flow_handler_t handle
, const char *name
)
597 set_irq_chip(irq
, chip
);
598 __set_irq_handler(irq
, handle
, 0, name
);