xref: /openbmc/linux/kernel/irq/chip.c (revision 483eb062)
1 /*
2  * linux/kernel/irq/chip.c
3  *
4  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
6  *
7  * This file contains the core interrupt handling code, for irq-chip
8  * based architectures.
9  *
10  * Detailed information is available in Documentation/DocBook/genericirq
11  */
12 
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>
18 
19 #include <trace/events/irq.h>
20 
21 #include "internals.h"
22 
23 /**
24  *	irq_set_chip - set the irq chip for an irq
25  *	@irq:	irq number
26  *	@chip:	pointer to irq chip description structure
27  */
28 int irq_set_chip(unsigned int irq, struct irq_chip *chip)
29 {
30 	unsigned long flags;
31 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
32 
33 	if (!desc)
34 		return -EINVAL;
35 
36 	if (!chip)
37 		chip = &no_irq_chip;
38 
39 	desc->irq_data.chip = chip;
40 	irq_put_desc_unlock(desc, flags);
41 	/*
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.
45 	 */
46 	irq_reserve_irq(irq);
47 	return 0;
48 }
49 EXPORT_SYMBOL(irq_set_chip);
50 
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
55  */
56 int irq_set_irq_type(unsigned int irq, unsigned int type)
57 {
58 	unsigned long flags;
59 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
60 	int ret = 0;
61 
62 	if (!desc)
63 		return -EINVAL;
64 
65 	type &= IRQ_TYPE_SENSE_MASK;
66 	ret = __irq_set_trigger(desc, irq, type);
67 	irq_put_desc_busunlock(desc, flags);
68 	return ret;
69 }
70 EXPORT_SYMBOL(irq_set_irq_type);
71 
72 /**
73  *	irq_set_handler_data - set irq handler data for an irq
74  *	@irq:	Interrupt number
75  *	@data:	Pointer to interrupt specific data
76  *
77  *	Set the hardware irq controller data for an irq
78  */
79 int irq_set_handler_data(unsigned int irq, void *data)
80 {
81 	unsigned long flags;
82 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
83 
84 	if (!desc)
85 		return -EINVAL;
86 	desc->irq_data.handler_data = data;
87 	irq_put_desc_unlock(desc, flags);
88 	return 0;
89 }
90 EXPORT_SYMBOL(irq_set_handler_data);
91 
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
97  *
98  *	Set the MSI descriptor entry for an irq at offset
99  */
100 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
101 			 struct msi_desc *entry)
102 {
103 	unsigned long flags;
104 	struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
105 
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;
113 }
114 
115 /**
116  *	irq_set_msi_desc - set MSI descriptor data for an irq
117  *	@irq:	Interrupt number
118  *	@entry:	Pointer to MSI descriptor data
119  *
120  *	Set the MSI descriptor entry for an irq
121  */
122 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
123 {
124 	return irq_set_msi_desc_off(irq, 0, entry);
125 }
126 
127 /**
128  *	irq_set_chip_data - set irq chip data for an irq
129  *	@irq:	Interrupt number
130  *	@data:	Pointer to chip specific data
131  *
132  *	Set the hardware irq chip data for an irq
133  */
134 int irq_set_chip_data(unsigned int irq, void *data)
135 {
136 	unsigned long flags;
137 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
138 
139 	if (!desc)
140 		return -EINVAL;
141 	desc->irq_data.chip_data = data;
142 	irq_put_desc_unlock(desc, flags);
143 	return 0;
144 }
145 EXPORT_SYMBOL(irq_set_chip_data);
146 
147 struct irq_data *irq_get_irq_data(unsigned int irq)
148 {
149 	struct irq_desc *desc = irq_to_desc(irq);
150 
151 	return desc ? &desc->irq_data : NULL;
152 }
153 EXPORT_SYMBOL_GPL(irq_get_irq_data);
154 
155 static void irq_state_clr_disabled(struct irq_desc *desc)
156 {
157 	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
158 }
159 
160 static void irq_state_set_disabled(struct irq_desc *desc)
161 {
162 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
163 }
164 
165 static void irq_state_clr_masked(struct irq_desc *desc)
166 {
167 	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
168 }
169 
170 static void irq_state_set_masked(struct irq_desc *desc)
171 {
172 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
173 }
174 
175 int irq_startup(struct irq_desc *desc, bool resend)
176 {
177 	int ret = 0;
178 
179 	irq_state_clr_disabled(desc);
180 	desc->depth = 0;
181 
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);
187 	}
188 	if (resend)
189 		check_irq_resend(desc, desc->irq_data.irq);
190 	return ret;
191 }
192 
193 void irq_shutdown(struct irq_desc *desc)
194 {
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);
204 }
205 
206 void irq_enable(struct irq_desc *desc)
207 {
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);
214 }
215 
216 /**
217  * irq_disable - Mark interrupt disabled
218  * @desc:	irq descriptor which should be disabled
219  *
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.
228  */
229 void irq_disable(struct irq_desc *desc)
230 {
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);
235 	}
236 }
237 
238 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
239 {
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);
245 }
246 
247 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
248 {
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);
254 }
255 
256 static inline void mask_ack_irq(struct irq_desc *desc)
257 {
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);
264 	}
265 	irq_state_set_masked(desc);
266 }
267 
268 void mask_irq(struct irq_desc *desc)
269 {
270 	if (desc->irq_data.chip->irq_mask) {
271 		desc->irq_data.chip->irq_mask(&desc->irq_data);
272 		irq_state_set_masked(desc);
273 	}
274 }
275 
276 void unmask_irq(struct irq_desc *desc)
277 {
278 	if (desc->irq_data.chip->irq_unmask) {
279 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
280 		irq_state_clr_masked(desc);
281 	}
282 }
283 
284 /*
285  *	handle_nested_irq - Handle a nested irq from a irq thread
286  *	@irq:	the interrupt number
287  *
288  *	Handle interrupts which are nested into a threaded interrupt
289  *	handler. The handler function is called inside the calling
290  *	threads context.
291  */
292 void handle_nested_irq(unsigned int irq)
293 {
294 	struct irq_desc *desc = irq_to_desc(irq);
295 	struct irqaction *action;
296 	irqreturn_t action_ret;
297 
298 	might_sleep();
299 
300 	raw_spin_lock_irq(&desc->lock);
301 
302 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
303 	kstat_incr_irqs_this_cpu(irq, desc);
304 
305 	action = desc->action;
306 	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
307 		desc->istate |= IRQS_PENDING;
308 		goto out_unlock;
309 	}
310 
311 	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
312 	raw_spin_unlock_irq(&desc->lock);
313 
314 	action_ret = action->thread_fn(action->irq, action->dev_id);
315 	if (!noirqdebug)
316 		note_interrupt(irq, desc, action_ret);
317 
318 	raw_spin_lock_irq(&desc->lock);
319 	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
320 
321 out_unlock:
322 	raw_spin_unlock_irq(&desc->lock);
323 }
324 EXPORT_SYMBOL_GPL(handle_nested_irq);
325 
326 static bool irq_check_poll(struct irq_desc *desc)
327 {
328 	if (!(desc->istate & IRQS_POLL_INPROGRESS))
329 		return false;
330 	return irq_wait_for_poll(desc);
331 }
332 
333 /**
334  *	handle_simple_irq - Simple and software-decoded IRQs.
335  *	@irq:	the interrupt number
336  *	@desc:	the interrupt description structure for this irq
337  *
338  *	Simple interrupts are either sent from a demultiplexing interrupt
339  *	handler or come from hardware, where no interrupt hardware control
340  *	is necessary.
341  *
342  *	Note: The caller is expected to handle the ack, clear, mask and
343  *	unmask issues if necessary.
344  */
345 void
346 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
347 {
348 	raw_spin_lock(&desc->lock);
349 
350 	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
351 		if (!irq_check_poll(desc))
352 			goto out_unlock;
353 
354 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
355 	kstat_incr_irqs_this_cpu(irq, desc);
356 
357 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
358 		desc->istate |= IRQS_PENDING;
359 		goto out_unlock;
360 	}
361 
362 	handle_irq_event(desc);
363 
364 out_unlock:
365 	raw_spin_unlock(&desc->lock);
366 }
367 EXPORT_SYMBOL_GPL(handle_simple_irq);
368 
369 /*
370  * Called unconditionally from handle_level_irq() and only for oneshot
371  * interrupts from handle_fasteoi_irq()
372  */
373 static void cond_unmask_irq(struct irq_desc *desc)
374 {
375 	/*
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).
381 	 */
382 	if (!irqd_irq_disabled(&desc->irq_data) &&
383 	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
384 		unmask_irq(desc);
385 }
386 
387 /**
388  *	handle_level_irq - Level type irq handler
389  *	@irq:	the interrupt number
390  *	@desc:	the interrupt description structure for this irq
391  *
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.
396  */
397 void
398 handle_level_irq(unsigned int irq, struct irq_desc *desc)
399 {
400 	raw_spin_lock(&desc->lock);
401 	mask_ack_irq(desc);
402 
403 	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
404 		if (!irq_check_poll(desc))
405 			goto out_unlock;
406 
407 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
408 	kstat_incr_irqs_this_cpu(irq, desc);
409 
410 	/*
411 	 * If its disabled or no action available
412 	 * keep it masked and get out of here
413 	 */
414 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
415 		desc->istate |= IRQS_PENDING;
416 		goto out_unlock;
417 	}
418 
419 	handle_irq_event(desc);
420 
421 	cond_unmask_irq(desc);
422 
423 out_unlock:
424 	raw_spin_unlock(&desc->lock);
425 }
426 EXPORT_SYMBOL_GPL(handle_level_irq);
427 
428 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
429 static inline void preflow_handler(struct irq_desc *desc)
430 {
431 	if (desc->preflow_handler)
432 		desc->preflow_handler(&desc->irq_data);
433 }
434 #else
435 static inline void preflow_handler(struct irq_desc *desc) { }
436 #endif
437 
438 /**
439  *	handle_fasteoi_irq - irq handler for transparent controllers
440  *	@irq:	the interrupt number
441  *	@desc:	the interrupt description structure for this irq
442  *
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.
447  */
448 void
449 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
450 {
451 	raw_spin_lock(&desc->lock);
452 
453 	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
454 		if (!irq_check_poll(desc))
455 			goto out;
456 
457 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
458 	kstat_incr_irqs_this_cpu(irq, desc);
459 
460 	/*
461 	 * If its disabled or no action available
462 	 * then mask it and get out of here:
463 	 */
464 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
465 		desc->istate |= IRQS_PENDING;
466 		mask_irq(desc);
467 		goto out;
468 	}
469 
470 	if (desc->istate & IRQS_ONESHOT)
471 		mask_irq(desc);
472 
473 	preflow_handler(desc);
474 	handle_irq_event(desc);
475 
476 	if (desc->istate & IRQS_ONESHOT)
477 		cond_unmask_irq(desc);
478 
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;
488 }
489 
490 /**
491  *	handle_edge_irq - edge type IRQ handler
492  *	@irq:	the interrupt number
493  *	@desc:	the interrupt description structure for this irq
494  *
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.
505  */
506 void
507 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
508 {
509 	raw_spin_lock(&desc->lock);
510 
511 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
512 	/*
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
516 	 */
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;
523 		}
524 	}
525 	kstat_incr_irqs_this_cpu(irq, desc);
526 
527 	/* Start handling the irq */
528 	desc->irq_data.chip->irq_ack(&desc->irq_data);
529 
530 	do {
531 		if (unlikely(!desc->action)) {
532 			mask_irq(desc);
533 			goto out_unlock;
534 		}
535 
536 		/*
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.
540 		 */
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);
545 		}
546 
547 		handle_irq_event(desc);
548 
549 	} while ((desc->istate & IRQS_PENDING) &&
550 		 !irqd_irq_disabled(&desc->irq_data));
551 
552 out_unlock:
553 	raw_spin_unlock(&desc->lock);
554 }
555 EXPORT_SYMBOL(handle_edge_irq);
556 
557 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
558 /**
559  *	handle_edge_eoi_irq - edge eoi type IRQ handler
560  *	@irq:	the interrupt number
561  *	@desc:	the interrupt description structure for this irq
562  *
563  * Similar as the above handle_edge_irq, but using eoi and w/o the
564  * mask/unmask logic.
565  */
566 void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
567 {
568 	struct irq_chip *chip = irq_desc_get_chip(desc);
569 
570 	raw_spin_lock(&desc->lock);
571 
572 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
573 	/*
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
577 	 */
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;
583 		}
584 	}
585 	kstat_incr_irqs_this_cpu(irq, desc);
586 
587 	do {
588 		if (unlikely(!desc->action))
589 			goto out_eoi;
590 
591 		handle_irq_event(desc);
592 
593 	} while ((desc->istate & IRQS_PENDING) &&
594 		 !irqd_irq_disabled(&desc->irq_data));
595 
596 out_eoi:
597 	chip->irq_eoi(&desc->irq_data);
598 	raw_spin_unlock(&desc->lock);
599 }
600 #endif
601 
602 /**
603  *	handle_percpu_irq - Per CPU local irq handler
604  *	@irq:	the interrupt number
605  *	@desc:	the interrupt description structure for this irq
606  *
607  *	Per CPU interrupts on SMP machines without locking requirements
608  */
609 void
610 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
611 {
612 	struct irq_chip *chip = irq_desc_get_chip(desc);
613 
614 	kstat_incr_irqs_this_cpu(irq, desc);
615 
616 	if (chip->irq_ack)
617 		chip->irq_ack(&desc->irq_data);
618 
619 	handle_irq_event_percpu(desc, desc->action);
620 
621 	if (chip->irq_eoi)
622 		chip->irq_eoi(&desc->irq_data);
623 }
624 
625 /**
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
629  *
630  * Per CPU interrupts on SMP machines without locking requirements. Same as
631  * handle_percpu_irq() above but with the following extras:
632  *
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
636  */
637 void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
638 {
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;
643 
644 	kstat_incr_irqs_this_cpu(irq, desc);
645 
646 	if (chip->irq_ack)
647 		chip->irq_ack(&desc->irq_data);
648 
649 	trace_irq_handler_entry(irq, action);
650 	res = action->handler(irq, dev_id);
651 	trace_irq_handler_exit(irq, action, res);
652 
653 	if (chip->irq_eoi)
654 		chip->irq_eoi(&desc->irq_data);
655 }
656 
657 void
658 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
659 		  const char *name)
660 {
661 	unsigned long flags;
662 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
663 
664 	if (!desc)
665 		return;
666 
667 	if (!handle) {
668 		handle = handle_bad_irq;
669 	} else {
670 		if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
671 			goto out;
672 	}
673 
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;
680 	}
681 	desc->handle_irq = handle;
682 	desc->name = name;
683 
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);
689 	}
690 out:
691 	irq_put_desc_busunlock(desc, flags);
692 }
693 EXPORT_SYMBOL_GPL(__irq_set_handler);
694 
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)
698 {
699 	irq_set_chip(irq, chip);
700 	__irq_set_handler(irq, handle, 0, name);
701 }
702 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
703 
704 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
705 {
706 	unsigned long flags;
707 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
708 
709 	if (!desc)
710 		return;
711 	irq_settings_clr_and_set(desc, clr, set);
712 
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);
723 
724 	irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
725 
726 	irq_put_desc_unlock(desc, flags);
727 }
728 EXPORT_SYMBOL_GPL(irq_modify_status);
729 
730 /**
731  *	irq_cpu_online - Invoke all irq_cpu_online functions.
732  *
733  *	Iterate through all irqs and invoke the chip.irq_cpu_online()
734  *	for each.
735  */
736 void irq_cpu_online(void)
737 {
738 	struct irq_desc *desc;
739 	struct irq_chip *chip;
740 	unsigned long flags;
741 	unsigned int irq;
742 
743 	for_each_active_irq(irq) {
744 		desc = irq_to_desc(irq);
745 		if (!desc)
746 			continue;
747 
748 		raw_spin_lock_irqsave(&desc->lock, flags);
749 
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);
755 
756 		raw_spin_unlock_irqrestore(&desc->lock, flags);
757 	}
758 }
759 
760 /**
761  *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
762  *
763  *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
764  *	for each.
765  */
766 void irq_cpu_offline(void)
767 {
768 	struct irq_desc *desc;
769 	struct irq_chip *chip;
770 	unsigned long flags;
771 	unsigned int irq;
772 
773 	for_each_active_irq(irq) {
774 		desc = irq_to_desc(irq);
775 		if (!desc)
776 			continue;
777 
778 		raw_spin_lock_irqsave(&desc->lock, flags);
779 
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);
785 
786 		raw_spin_unlock_irqrestore(&desc->lock, flags);
787 	}
788 }
789