serial: imx: check the DMA for imx_tx_empty
[linux-2.6/btrfs-unstable.git] / kernel / irq / chip.c
bloba3bb14fbe5c61fec344a166f8b542571dab4704c
1 /*
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
8 * based architectures.
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 <trace/events/irq.h>
21 #include "internals.h"
23 /**
24 * irq_set_chip - set the irq chip for an irq
25 * @irq: irq number
26 * @chip: pointer to irq chip description structure
28 int irq_set_chip(unsigned int irq, struct irq_chip *chip)
30 unsigned long flags;
31 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
33 if (!desc)
34 return -EINVAL;
36 if (!chip)
37 chip = &no_irq_chip;
39 desc->irq_data.chip = chip;
40 irq_put_desc_unlock(desc, flags);
42 * For !CONFIG_SPARSE_IRQ make the irq show up in
43 * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is
44 * already marked, and this call is harmless.
46 irq_reserve_irq(irq);
47 return 0;
49 EXPORT_SYMBOL(irq_set_chip);
51 /**
52 * irq_set_type - set the irq trigger type for an irq
53 * @irq: irq number
54 * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
56 int irq_set_irq_type(unsigned int irq, unsigned int type)
58 unsigned long flags;
59 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
60 int ret = 0;
62 if (!desc)
63 return -EINVAL;
65 type &= IRQ_TYPE_SENSE_MASK;
66 ret = __irq_set_trigger(desc, irq, type);
67 irq_put_desc_busunlock(desc, flags);
68 return ret;
70 EXPORT_SYMBOL(irq_set_irq_type);
72 /**
73 * irq_set_handler_data - set irq handler data for an irq
74 * @irq: Interrupt number
75 * @data: Pointer to interrupt specific data
77 * Set the hardware irq controller data for an irq
79 int irq_set_handler_data(unsigned int irq, void *data)
81 unsigned long flags;
82 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
84 if (!desc)
85 return -EINVAL;
86 desc->irq_data.handler_data = data;
87 irq_put_desc_unlock(desc, flags);
88 return 0;
90 EXPORT_SYMBOL(irq_set_handler_data);
92 /**
93 * irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
94 * @irq_base: Interrupt number base
95 * @irq_offset: Interrupt number offset
96 * @entry: Pointer to MSI descriptor data
98 * Set the MSI descriptor entry for an irq at offset
100 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
101 struct msi_desc *entry)
103 unsigned long flags;
104 struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
106 if (!desc)
107 return -EINVAL;
108 desc->irq_data.msi_desc = entry;
109 if (entry && !irq_offset)
110 entry->irq = irq_base;
111 irq_put_desc_unlock(desc, flags);
112 return 0;
116 * irq_set_msi_desc - set MSI descriptor data for an irq
117 * @irq: Interrupt number
118 * @entry: Pointer to MSI descriptor data
120 * Set the MSI descriptor entry for an irq
122 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
124 return irq_set_msi_desc_off(irq, 0, entry);
128 * irq_set_chip_data - set irq chip data for an irq
129 * @irq: Interrupt number
130 * @data: Pointer to chip specific data
132 * Set the hardware irq chip data for an irq
134 int irq_set_chip_data(unsigned int irq, void *data)
136 unsigned long flags;
137 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
139 if (!desc)
140 return -EINVAL;
141 desc->irq_data.chip_data = data;
142 irq_put_desc_unlock(desc, flags);
143 return 0;
145 EXPORT_SYMBOL(irq_set_chip_data);
147 struct irq_data *irq_get_irq_data(unsigned int irq)
149 struct irq_desc *desc = irq_to_desc(irq);
151 return desc ? &desc->irq_data : NULL;
153 EXPORT_SYMBOL_GPL(irq_get_irq_data);
155 static void irq_state_clr_disabled(struct irq_desc *desc)
157 irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
160 static void irq_state_set_disabled(struct irq_desc *desc)
162 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
165 static void irq_state_clr_masked(struct irq_desc *desc)
167 irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
170 static void irq_state_set_masked(struct irq_desc *desc)
172 irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
175 int irq_startup(struct irq_desc *desc, bool resend)
177 int ret = 0;
179 irq_state_clr_disabled(desc);
180 desc->depth = 0;
182 if (desc->irq_data.chip->irq_startup) {
183 ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
184 irq_state_clr_masked(desc);
185 } else {
186 irq_enable(desc);
188 if (resend)
189 check_irq_resend(desc, desc->irq_data.irq);
190 return ret;
193 void irq_shutdown(struct irq_desc *desc)
195 irq_state_set_disabled(desc);
196 desc->depth = 1;
197 if (desc->irq_data.chip->irq_shutdown)
198 desc->irq_data.chip->irq_shutdown(&desc->irq_data);
199 else if (desc->irq_data.chip->irq_disable)
200 desc->irq_data.chip->irq_disable(&desc->irq_data);
201 else
202 desc->irq_data.chip->irq_mask(&desc->irq_data);
203 irq_state_set_masked(desc);
206 void irq_enable(struct irq_desc *desc)
208 irq_state_clr_disabled(desc);
209 if (desc->irq_data.chip->irq_enable)
210 desc->irq_data.chip->irq_enable(&desc->irq_data);
211 else
212 desc->irq_data.chip->irq_unmask(&desc->irq_data);
213 irq_state_clr_masked(desc);
217 * irq_disable - Mark interupt disabled
218 * @desc: irq descriptor which should be disabled
220 * If the chip does not implement the irq_disable callback, we
221 * use a lazy disable approach. That means we mark the interrupt
222 * disabled, but leave the hardware unmasked. That's an
223 * optimization because we avoid the hardware access for the
224 * common case where no interrupt happens after we marked it
225 * disabled. If an interrupt happens, then the interrupt flow
226 * handler masks the line at the hardware level and marks it
227 * pending.
229 void irq_disable(struct irq_desc *desc)
231 irq_state_set_disabled(desc);
232 if (desc->irq_data.chip->irq_disable) {
233 desc->irq_data.chip->irq_disable(&desc->irq_data);
234 irq_state_set_masked(desc);
238 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
240 if (desc->irq_data.chip->irq_enable)
241 desc->irq_data.chip->irq_enable(&desc->irq_data);
242 else
243 desc->irq_data.chip->irq_unmask(&desc->irq_data);
244 cpumask_set_cpu(cpu, desc->percpu_enabled);
247 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
249 if (desc->irq_data.chip->irq_disable)
250 desc->irq_data.chip->irq_disable(&desc->irq_data);
251 else
252 desc->irq_data.chip->irq_mask(&desc->irq_data);
253 cpumask_clear_cpu(cpu, desc->percpu_enabled);
256 static inline void mask_ack_irq(struct irq_desc *desc)
258 if (desc->irq_data.chip->irq_mask_ack)
259 desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
260 else {
261 desc->irq_data.chip->irq_mask(&desc->irq_data);
262 if (desc->irq_data.chip->irq_ack)
263 desc->irq_data.chip->irq_ack(&desc->irq_data);
265 irq_state_set_masked(desc);
268 void mask_irq(struct irq_desc *desc)
270 if (desc->irq_data.chip->irq_mask) {
271 desc->irq_data.chip->irq_mask(&desc->irq_data);
272 irq_state_set_masked(desc);
276 void unmask_irq(struct irq_desc *desc)
278 if (desc->irq_data.chip->irq_unmask) {
279 desc->irq_data.chip->irq_unmask(&desc->irq_data);
280 irq_state_clr_masked(desc);
285 * handle_nested_irq - Handle a nested irq from a irq thread
286 * @irq: the interrupt number
288 * Handle interrupts which are nested into a threaded interrupt
289 * handler. The handler function is called inside the calling
290 * threads context.
292 void handle_nested_irq(unsigned int irq)
294 struct irq_desc *desc = irq_to_desc(irq);
295 struct irqaction *action;
296 irqreturn_t action_ret;
298 might_sleep();
300 raw_spin_lock_irq(&desc->lock);
302 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
303 kstat_incr_irqs_this_cpu(irq, desc);
305 action = desc->action;
306 if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
307 desc->istate |= IRQS_PENDING;
308 goto out_unlock;
311 irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
312 raw_spin_unlock_irq(&desc->lock);
314 action_ret = action->thread_fn(action->irq, action->dev_id);
315 if (!noirqdebug)
316 note_interrupt(irq, desc, action_ret);
318 raw_spin_lock_irq(&desc->lock);
319 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
321 out_unlock:
322 raw_spin_unlock_irq(&desc->lock);
324 EXPORT_SYMBOL_GPL(handle_nested_irq);
326 static bool irq_check_poll(struct irq_desc *desc)
328 if (!(desc->istate & IRQS_POLL_INPROGRESS))
329 return false;
330 return irq_wait_for_poll(desc);
334 * handle_simple_irq - Simple and software-decoded IRQs.
335 * @irq: the interrupt number
336 * @desc: the interrupt description structure for this irq
338 * Simple interrupts are either sent from a demultiplexing interrupt
339 * handler or come from hardware, where no interrupt hardware control
340 * is necessary.
342 * Note: The caller is expected to handle the ack, clear, mask and
343 * unmask issues if necessary.
345 void
346 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
348 raw_spin_lock(&desc->lock);
350 if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
351 if (!irq_check_poll(desc))
352 goto out_unlock;
354 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
355 kstat_incr_irqs_this_cpu(irq, desc);
357 if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
358 desc->istate |= IRQS_PENDING;
359 goto out_unlock;
362 handle_irq_event(desc);
364 out_unlock:
365 raw_spin_unlock(&desc->lock);
367 EXPORT_SYMBOL_GPL(handle_simple_irq);
370 * Called unconditionally from handle_level_irq() and only for oneshot
371 * interrupts from handle_fasteoi_irq()
373 static void cond_unmask_irq(struct irq_desc *desc)
376 * We need to unmask in the following cases:
377 * - Standard level irq (IRQF_ONESHOT is not set)
378 * - Oneshot irq which did not wake the thread (caused by a
379 * spurious interrupt or a primary handler handling it
380 * completely).
382 if (!irqd_irq_disabled(&desc->irq_data) &&
383 irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
384 unmask_irq(desc);
388 * handle_level_irq - Level type irq handler
389 * @irq: the interrupt number
390 * @desc: the interrupt description structure for this irq
392 * Level type interrupts are active as long as the hardware line has
393 * the active level. This may require to mask the interrupt and unmask
394 * it after the associated handler has acknowledged the device, so the
395 * interrupt line is back to inactive.
397 void
398 handle_level_irq(unsigned int irq, struct irq_desc *desc)
400 raw_spin_lock(&desc->lock);
401 mask_ack_irq(desc);
403 if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
404 if (!irq_check_poll(desc))
405 goto out_unlock;
407 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
408 kstat_incr_irqs_this_cpu(irq, desc);
411 * If its disabled or no action available
412 * keep it masked and get out of here
414 if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
415 desc->istate |= IRQS_PENDING;
416 goto out_unlock;
419 handle_irq_event(desc);
421 cond_unmask_irq(desc);
423 out_unlock:
424 raw_spin_unlock(&desc->lock);
426 EXPORT_SYMBOL_GPL(handle_level_irq);
428 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
429 static inline void preflow_handler(struct irq_desc *desc)
431 if (desc->preflow_handler)
432 desc->preflow_handler(&desc->irq_data);
434 #else
435 static inline void preflow_handler(struct irq_desc *desc) { }
436 #endif
439 * handle_fasteoi_irq - irq handler for transparent controllers
440 * @irq: the interrupt number
441 * @desc: the interrupt description structure for this irq
443 * Only a single callback will be issued to the chip: an ->eoi()
444 * call when the interrupt has been serviced. This enables support
445 * for modern forms of interrupt handlers, which handle the flow
446 * details in hardware, transparently.
448 void
449 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
451 raw_spin_lock(&desc->lock);
453 if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
454 if (!irq_check_poll(desc))
455 goto out;
457 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
458 kstat_incr_irqs_this_cpu(irq, desc);
461 * If its disabled or no action available
462 * then mask it and get out of here:
464 if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
465 desc->istate |= IRQS_PENDING;
466 mask_irq(desc);
467 goto out;
470 if (desc->istate & IRQS_ONESHOT)
471 mask_irq(desc);
473 preflow_handler(desc);
474 handle_irq_event(desc);
476 if (desc->istate & IRQS_ONESHOT)
477 cond_unmask_irq(desc);
479 out_eoi:
480 desc->irq_data.chip->irq_eoi(&desc->irq_data);
481 out_unlock:
482 raw_spin_unlock(&desc->lock);
483 return;
484 out:
485 if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED))
486 goto out_eoi;
487 goto out_unlock;
491 * handle_edge_irq - edge type IRQ handler
492 * @irq: the interrupt number
493 * @desc: the interrupt description structure for this irq
495 * Interrupt occures on the falling and/or rising edge of a hardware
496 * signal. The occurrence is latched into the irq controller hardware
497 * and must be acked in order to be reenabled. After the ack another
498 * interrupt can happen on the same source even before the first one
499 * is handled by the associated event handler. If this happens it
500 * might be necessary to disable (mask) the interrupt depending on the
501 * controller hardware. This requires to reenable the interrupt inside
502 * of the loop which handles the interrupts which have arrived while
503 * the handler was running. If all pending interrupts are handled, the
504 * loop is left.
506 void
507 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
509 raw_spin_lock(&desc->lock);
511 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
513 * If we're currently running this IRQ, or its disabled,
514 * we shouldn't process the IRQ. Mark it pending, handle
515 * the necessary masking and go out
517 if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
518 irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
519 if (!irq_check_poll(desc)) {
520 desc->istate |= IRQS_PENDING;
521 mask_ack_irq(desc);
522 goto out_unlock;
525 kstat_incr_irqs_this_cpu(irq, desc);
527 /* Start handling the irq */
528 desc->irq_data.chip->irq_ack(&desc->irq_data);
530 do {
531 if (unlikely(!desc->action)) {
532 mask_irq(desc);
533 goto out_unlock;
537 * When another irq arrived while we were handling
538 * one, we could have masked the irq.
539 * Renable it, if it was not disabled in meantime.
541 if (unlikely(desc->istate & IRQS_PENDING)) {
542 if (!irqd_irq_disabled(&desc->irq_data) &&
543 irqd_irq_masked(&desc->irq_data))
544 unmask_irq(desc);
547 handle_irq_event(desc);
549 } while ((desc->istate & IRQS_PENDING) &&
550 !irqd_irq_disabled(&desc->irq_data));
552 out_unlock:
553 raw_spin_unlock(&desc->lock);
555 EXPORT_SYMBOL(handle_edge_irq);
557 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
559 * handle_edge_eoi_irq - edge eoi type IRQ handler
560 * @irq: the interrupt number
561 * @desc: the interrupt description structure for this irq
563 * Similar as the above handle_edge_irq, but using eoi and w/o the
564 * mask/unmask logic.
566 void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
568 struct irq_chip *chip = irq_desc_get_chip(desc);
570 raw_spin_lock(&desc->lock);
572 desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
574 * If we're currently running this IRQ, or its disabled,
575 * we shouldn't process the IRQ. Mark it pending, handle
576 * the necessary masking and go out
578 if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
579 irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
580 if (!irq_check_poll(desc)) {
581 desc->istate |= IRQS_PENDING;
582 goto out_eoi;
585 kstat_incr_irqs_this_cpu(irq, desc);
587 do {
588 if (unlikely(!desc->action))
589 goto out_eoi;
591 handle_irq_event(desc);
593 } while ((desc->istate & IRQS_PENDING) &&
594 !irqd_irq_disabled(&desc->irq_data));
596 out_eoi:
597 chip->irq_eoi(&desc->irq_data);
598 raw_spin_unlock(&desc->lock);
600 #endif
603 * handle_percpu_irq - Per CPU local irq handler
604 * @irq: the interrupt number
605 * @desc: the interrupt description structure for this irq
607 * Per CPU interrupts on SMP machines without locking requirements
609 void
610 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
612 struct irq_chip *chip = irq_desc_get_chip(desc);
614 kstat_incr_irqs_this_cpu(irq, desc);
616 if (chip->irq_ack)
617 chip->irq_ack(&desc->irq_data);
619 handle_irq_event_percpu(desc, desc->action);
621 if (chip->irq_eoi)
622 chip->irq_eoi(&desc->irq_data);
626 * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
627 * @irq: the interrupt number
628 * @desc: the interrupt description structure for this irq
630 * Per CPU interrupts on SMP machines without locking requirements. Same as
631 * handle_percpu_irq() above but with the following extras:
633 * action->percpu_dev_id is a pointer to percpu variables which
634 * contain the real device id for the cpu on which this handler is
635 * called
637 void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
639 struct irq_chip *chip = irq_desc_get_chip(desc);
640 struct irqaction *action = desc->action;
641 void *dev_id = __this_cpu_ptr(action->percpu_dev_id);
642 irqreturn_t res;
644 kstat_incr_irqs_this_cpu(irq, desc);
646 if (chip->irq_ack)
647 chip->irq_ack(&desc->irq_data);
649 trace_irq_handler_entry(irq, action);
650 res = action->handler(irq, dev_id);
651 trace_irq_handler_exit(irq, action, res);
653 if (chip->irq_eoi)
654 chip->irq_eoi(&desc->irq_data);
657 void
658 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
659 const char *name)
661 unsigned long flags;
662 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
664 if (!desc)
665 return;
667 if (!handle) {
668 handle = handle_bad_irq;
669 } else {
670 if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
671 goto out;
674 /* Uninstall? */
675 if (handle == handle_bad_irq) {
676 if (desc->irq_data.chip != &no_irq_chip)
677 mask_ack_irq(desc);
678 irq_state_set_disabled(desc);
679 desc->depth = 1;
681 desc->handle_irq = handle;
682 desc->name = name;
684 if (handle != handle_bad_irq && is_chained) {
685 irq_settings_set_noprobe(desc);
686 irq_settings_set_norequest(desc);
687 irq_settings_set_nothread(desc);
688 irq_startup(desc, true);
690 out:
691 irq_put_desc_busunlock(desc, flags);
693 EXPORT_SYMBOL_GPL(__irq_set_handler);
695 void
696 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
697 irq_flow_handler_t handle, const char *name)
699 irq_set_chip(irq, chip);
700 __irq_set_handler(irq, handle, 0, name);
702 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
704 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
706 unsigned long flags;
707 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
709 if (!desc)
710 return;
711 irq_settings_clr_and_set(desc, clr, set);
713 irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
714 IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
715 if (irq_settings_has_no_balance_set(desc))
716 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
717 if (irq_settings_is_per_cpu(desc))
718 irqd_set(&desc->irq_data, IRQD_PER_CPU);
719 if (irq_settings_can_move_pcntxt(desc))
720 irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
721 if (irq_settings_is_level(desc))
722 irqd_set(&desc->irq_data, IRQD_LEVEL);
724 irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
726 irq_put_desc_unlock(desc, flags);
728 EXPORT_SYMBOL_GPL(irq_modify_status);
731 * irq_cpu_online - Invoke all irq_cpu_online functions.
733 * Iterate through all irqs and invoke the chip.irq_cpu_online()
734 * for each.
736 void irq_cpu_online(void)
738 struct irq_desc *desc;
739 struct irq_chip *chip;
740 unsigned long flags;
741 unsigned int irq;
743 for_each_active_irq(irq) {
744 desc = irq_to_desc(irq);
745 if (!desc)
746 continue;
748 raw_spin_lock_irqsave(&desc->lock, flags);
750 chip = irq_data_get_irq_chip(&desc->irq_data);
751 if (chip && chip->irq_cpu_online &&
752 (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
753 !irqd_irq_disabled(&desc->irq_data)))
754 chip->irq_cpu_online(&desc->irq_data);
756 raw_spin_unlock_irqrestore(&desc->lock, flags);
761 * irq_cpu_offline - Invoke all irq_cpu_offline functions.
763 * Iterate through all irqs and invoke the chip.irq_cpu_offline()
764 * for each.
766 void irq_cpu_offline(void)
768 struct irq_desc *desc;
769 struct irq_chip *chip;
770 unsigned long flags;
771 unsigned int irq;
773 for_each_active_irq(irq) {
774 desc = irq_to_desc(irq);
775 if (!desc)
776 continue;
778 raw_spin_lock_irqsave(&desc->lock, flags);
780 chip = irq_data_get_irq_chip(&desc->irq_data);
781 if (chip && chip->irq_cpu_offline &&
782 (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
783 !irqd_irq_disabled(&desc->irq_data)))
784 chip->irq_cpu_offline(&desc->irq_data);
786 raw_spin_unlock_irqrestore(&desc->lock, flags);