Merge branch 'linux-3.17' of git://anongit.freedesktop.org/git/nouveau/linux-2.6...
[cascardo/linux.git] / kernel / irq / chip.c
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.
44          */
45         irq_mark_irq(irq);
46         return 0;
47 }
48 EXPORT_SYMBOL(irq_set_chip);
49
50 /**
51  *      irq_set_type - set the irq trigger type for an irq
52  *      @irq:   irq number
53  *      @type:  IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
54  */
55 int irq_set_irq_type(unsigned int irq, unsigned int type)
56 {
57         unsigned long flags;
58         struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
59         int ret = 0;
60
61         if (!desc)
62                 return -EINVAL;
63
64         type &= IRQ_TYPE_SENSE_MASK;
65         ret = __irq_set_trigger(desc, irq, type);
66         irq_put_desc_busunlock(desc, flags);
67         return ret;
68 }
69 EXPORT_SYMBOL(irq_set_irq_type);
70
71 /**
72  *      irq_set_handler_data - set irq handler data for an irq
73  *      @irq:   Interrupt number
74  *      @data:  Pointer to interrupt specific data
75  *
76  *      Set the hardware irq controller data for an irq
77  */
78 int irq_set_handler_data(unsigned int irq, void *data)
79 {
80         unsigned long flags;
81         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
82
83         if (!desc)
84                 return -EINVAL;
85         desc->irq_data.handler_data = data;
86         irq_put_desc_unlock(desc, flags);
87         return 0;
88 }
89 EXPORT_SYMBOL(irq_set_handler_data);
90
91 /**
92  *      irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
93  *      @irq_base:      Interrupt number base
94  *      @irq_offset:    Interrupt number offset
95  *      @entry:         Pointer to MSI descriptor data
96  *
97  *      Set the MSI descriptor entry for an irq at offset
98  */
99 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
100                          struct msi_desc *entry)
101 {
102         unsigned long flags;
103         struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
104
105         if (!desc)
106                 return -EINVAL;
107         desc->irq_data.msi_desc = entry;
108         if (entry && !irq_offset)
109                 entry->irq = irq_base;
110         irq_put_desc_unlock(desc, flags);
111         return 0;
112 }
113
114 /**
115  *      irq_set_msi_desc - set MSI descriptor data for an irq
116  *      @irq:   Interrupt number
117  *      @entry: Pointer to MSI descriptor data
118  *
119  *      Set the MSI descriptor entry for an irq
120  */
121 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
122 {
123         return irq_set_msi_desc_off(irq, 0, entry);
124 }
125
126 /**
127  *      irq_set_chip_data - set irq chip data for an irq
128  *      @irq:   Interrupt number
129  *      @data:  Pointer to chip specific data
130  *
131  *      Set the hardware irq chip data for an irq
132  */
133 int irq_set_chip_data(unsigned int irq, void *data)
134 {
135         unsigned long flags;
136         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
137
138         if (!desc)
139                 return -EINVAL;
140         desc->irq_data.chip_data = data;
141         irq_put_desc_unlock(desc, flags);
142         return 0;
143 }
144 EXPORT_SYMBOL(irq_set_chip_data);
145
146 struct irq_data *irq_get_irq_data(unsigned int irq)
147 {
148         struct irq_desc *desc = irq_to_desc(irq);
149
150         return desc ? &desc->irq_data : NULL;
151 }
152 EXPORT_SYMBOL_GPL(irq_get_irq_data);
153
154 static void irq_state_clr_disabled(struct irq_desc *desc)
155 {
156         irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
157 }
158
159 static void irq_state_set_disabled(struct irq_desc *desc)
160 {
161         irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
162 }
163
164 static void irq_state_clr_masked(struct irq_desc *desc)
165 {
166         irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
167 }
168
169 static void irq_state_set_masked(struct irq_desc *desc)
170 {
171         irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
172 }
173
174 int irq_startup(struct irq_desc *desc, bool resend)
175 {
176         int ret = 0;
177
178         irq_state_clr_disabled(desc);
179         desc->depth = 0;
180
181         if (desc->irq_data.chip->irq_startup) {
182                 ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
183                 irq_state_clr_masked(desc);
184         } else {
185                 irq_enable(desc);
186         }
187         if (resend)
188                 check_irq_resend(desc, desc->irq_data.irq);
189         return ret;
190 }
191
192 void irq_shutdown(struct irq_desc *desc)
193 {
194         irq_state_set_disabled(desc);
195         desc->depth = 1;
196         if (desc->irq_data.chip->irq_shutdown)
197                 desc->irq_data.chip->irq_shutdown(&desc->irq_data);
198         else if (desc->irq_data.chip->irq_disable)
199                 desc->irq_data.chip->irq_disable(&desc->irq_data);
200         else
201                 desc->irq_data.chip->irq_mask(&desc->irq_data);
202         irq_state_set_masked(desc);
203 }
204
205 void irq_enable(struct irq_desc *desc)
206 {
207         irq_state_clr_disabled(desc);
208         if (desc->irq_data.chip->irq_enable)
209                 desc->irq_data.chip->irq_enable(&desc->irq_data);
210         else
211                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
212         irq_state_clr_masked(desc);
213 }
214
215 /**
216  * irq_disable - Mark interrupt disabled
217  * @desc:       irq descriptor which should be disabled
218  *
219  * If the chip does not implement the irq_disable callback, we
220  * use a lazy disable approach. That means we mark the interrupt
221  * disabled, but leave the hardware unmasked. That's an
222  * optimization because we avoid the hardware access for the
223  * common case where no interrupt happens after we marked it
224  * disabled. If an interrupt happens, then the interrupt flow
225  * handler masks the line at the hardware level and marks it
226  * pending.
227  */
228 void irq_disable(struct irq_desc *desc)
229 {
230         irq_state_set_disabled(desc);
231         if (desc->irq_data.chip->irq_disable) {
232                 desc->irq_data.chip->irq_disable(&desc->irq_data);
233                 irq_state_set_masked(desc);
234         }
235 }
236
237 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
238 {
239         if (desc->irq_data.chip->irq_enable)
240                 desc->irq_data.chip->irq_enable(&desc->irq_data);
241         else
242                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
243         cpumask_set_cpu(cpu, desc->percpu_enabled);
244 }
245
246 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
247 {
248         if (desc->irq_data.chip->irq_disable)
249                 desc->irq_data.chip->irq_disable(&desc->irq_data);
250         else
251                 desc->irq_data.chip->irq_mask(&desc->irq_data);
252         cpumask_clear_cpu(cpu, desc->percpu_enabled);
253 }
254
255 static inline void mask_ack_irq(struct irq_desc *desc)
256 {
257         if (desc->irq_data.chip->irq_mask_ack)
258                 desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
259         else {
260                 desc->irq_data.chip->irq_mask(&desc->irq_data);
261                 if (desc->irq_data.chip->irq_ack)
262                         desc->irq_data.chip->irq_ack(&desc->irq_data);
263         }
264         irq_state_set_masked(desc);
265 }
266
267 void mask_irq(struct irq_desc *desc)
268 {
269         if (desc->irq_data.chip->irq_mask) {
270                 desc->irq_data.chip->irq_mask(&desc->irq_data);
271                 irq_state_set_masked(desc);
272         }
273 }
274
275 void unmask_irq(struct irq_desc *desc)
276 {
277         if (desc->irq_data.chip->irq_unmask) {
278                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
279                 irq_state_clr_masked(desc);
280         }
281 }
282
283 void unmask_threaded_irq(struct irq_desc *desc)
284 {
285         struct irq_chip *chip = desc->irq_data.chip;
286
287         if (chip->flags & IRQCHIP_EOI_THREADED)
288                 chip->irq_eoi(&desc->irq_data);
289
290         if (chip->irq_unmask) {
291                 chip->irq_unmask(&desc->irq_data);
292                 irq_state_clr_masked(desc);
293         }
294 }
295
296 /*
297  *      handle_nested_irq - Handle a nested irq from a irq thread
298  *      @irq:   the interrupt number
299  *
300  *      Handle interrupts which are nested into a threaded interrupt
301  *      handler. The handler function is called inside the calling
302  *      threads context.
303  */
304 void handle_nested_irq(unsigned int irq)
305 {
306         struct irq_desc *desc = irq_to_desc(irq);
307         struct irqaction *action;
308         irqreturn_t action_ret;
309
310         might_sleep();
311
312         raw_spin_lock_irq(&desc->lock);
313
314         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
315         kstat_incr_irqs_this_cpu(irq, desc);
316
317         action = desc->action;
318         if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
319                 desc->istate |= IRQS_PENDING;
320                 goto out_unlock;
321         }
322
323         irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
324         raw_spin_unlock_irq(&desc->lock);
325
326         action_ret = action->thread_fn(action->irq, action->dev_id);
327         if (!noirqdebug)
328                 note_interrupt(irq, desc, action_ret);
329
330         raw_spin_lock_irq(&desc->lock);
331         irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
332
333 out_unlock:
334         raw_spin_unlock_irq(&desc->lock);
335 }
336 EXPORT_SYMBOL_GPL(handle_nested_irq);
337
338 static bool irq_check_poll(struct irq_desc *desc)
339 {
340         if (!(desc->istate & IRQS_POLL_INPROGRESS))
341                 return false;
342         return irq_wait_for_poll(desc);
343 }
344
345 /**
346  *      handle_simple_irq - Simple and software-decoded IRQs.
347  *      @irq:   the interrupt number
348  *      @desc:  the interrupt description structure for this irq
349  *
350  *      Simple interrupts are either sent from a demultiplexing interrupt
351  *      handler or come from hardware, where no interrupt hardware control
352  *      is necessary.
353  *
354  *      Note: The caller is expected to handle the ack, clear, mask and
355  *      unmask issues if necessary.
356  */
357 void
358 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
359 {
360         raw_spin_lock(&desc->lock);
361
362         if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
363                 if (!irq_check_poll(desc))
364                         goto out_unlock;
365
366         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
367         kstat_incr_irqs_this_cpu(irq, desc);
368
369         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
370                 desc->istate |= IRQS_PENDING;
371                 goto out_unlock;
372         }
373
374         handle_irq_event(desc);
375
376 out_unlock:
377         raw_spin_unlock(&desc->lock);
378 }
379 EXPORT_SYMBOL_GPL(handle_simple_irq);
380
381 /*
382  * Called unconditionally from handle_level_irq() and only for oneshot
383  * interrupts from handle_fasteoi_irq()
384  */
385 static void cond_unmask_irq(struct irq_desc *desc)
386 {
387         /*
388          * We need to unmask in the following cases:
389          * - Standard level irq (IRQF_ONESHOT is not set)
390          * - Oneshot irq which did not wake the thread (caused by a
391          *   spurious interrupt or a primary handler handling it
392          *   completely).
393          */
394         if (!irqd_irq_disabled(&desc->irq_data) &&
395             irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
396                 unmask_irq(desc);
397 }
398
399 /**
400  *      handle_level_irq - Level type irq handler
401  *      @irq:   the interrupt number
402  *      @desc:  the interrupt description structure for this irq
403  *
404  *      Level type interrupts are active as long as the hardware line has
405  *      the active level. This may require to mask the interrupt and unmask
406  *      it after the associated handler has acknowledged the device, so the
407  *      interrupt line is back to inactive.
408  */
409 void
410 handle_level_irq(unsigned int irq, struct irq_desc *desc)
411 {
412         raw_spin_lock(&desc->lock);
413         mask_ack_irq(desc);
414
415         if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
416                 if (!irq_check_poll(desc))
417                         goto out_unlock;
418
419         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
420         kstat_incr_irqs_this_cpu(irq, desc);
421
422         /*
423          * If its disabled or no action available
424          * keep it masked and get out of here
425          */
426         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
427                 desc->istate |= IRQS_PENDING;
428                 goto out_unlock;
429         }
430
431         handle_irq_event(desc);
432
433         cond_unmask_irq(desc);
434
435 out_unlock:
436         raw_spin_unlock(&desc->lock);
437 }
438 EXPORT_SYMBOL_GPL(handle_level_irq);
439
440 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
441 static inline void preflow_handler(struct irq_desc *desc)
442 {
443         if (desc->preflow_handler)
444                 desc->preflow_handler(&desc->irq_data);
445 }
446 #else
447 static inline void preflow_handler(struct irq_desc *desc) { }
448 #endif
449
450 static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
451 {
452         if (!(desc->istate & IRQS_ONESHOT)) {
453                 chip->irq_eoi(&desc->irq_data);
454                 return;
455         }
456         /*
457          * We need to unmask in the following cases:
458          * - Oneshot irq which did not wake the thread (caused by a
459          *   spurious interrupt or a primary handler handling it
460          *   completely).
461          */
462         if (!irqd_irq_disabled(&desc->irq_data) &&
463             irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
464                 chip->irq_eoi(&desc->irq_data);
465                 unmask_irq(desc);
466         } else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
467                 chip->irq_eoi(&desc->irq_data);
468         }
469 }
470
471 /**
472  *      handle_fasteoi_irq - irq handler for transparent controllers
473  *      @irq:   the interrupt number
474  *      @desc:  the interrupt description structure for this irq
475  *
476  *      Only a single callback will be issued to the chip: an ->eoi()
477  *      call when the interrupt has been serviced. This enables support
478  *      for modern forms of interrupt handlers, which handle the flow
479  *      details in hardware, transparently.
480  */
481 void
482 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
483 {
484         struct irq_chip *chip = desc->irq_data.chip;
485
486         raw_spin_lock(&desc->lock);
487
488         if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
489                 if (!irq_check_poll(desc))
490                         goto out;
491
492         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
493         kstat_incr_irqs_this_cpu(irq, desc);
494
495         /*
496          * If its disabled or no action available
497          * then mask it and get out of here:
498          */
499         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
500                 desc->istate |= IRQS_PENDING;
501                 mask_irq(desc);
502                 goto out;
503         }
504
505         if (desc->istate & IRQS_ONESHOT)
506                 mask_irq(desc);
507
508         preflow_handler(desc);
509         handle_irq_event(desc);
510
511         cond_unmask_eoi_irq(desc, chip);
512
513         raw_spin_unlock(&desc->lock);
514         return;
515 out:
516         if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
517                 chip->irq_eoi(&desc->irq_data);
518         raw_spin_unlock(&desc->lock);
519 }
520
521 /**
522  *      handle_edge_irq - edge type IRQ handler
523  *      @irq:   the interrupt number
524  *      @desc:  the interrupt description structure for this irq
525  *
526  *      Interrupt occures on the falling and/or rising edge of a hardware
527  *      signal. The occurrence is latched into the irq controller hardware
528  *      and must be acked in order to be reenabled. After the ack another
529  *      interrupt can happen on the same source even before the first one
530  *      is handled by the associated event handler. If this happens it
531  *      might be necessary to disable (mask) the interrupt depending on the
532  *      controller hardware. This requires to reenable the interrupt inside
533  *      of the loop which handles the interrupts which have arrived while
534  *      the handler was running. If all pending interrupts are handled, the
535  *      loop is left.
536  */
537 void
538 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
539 {
540         raw_spin_lock(&desc->lock);
541
542         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
543         /*
544          * If we're currently running this IRQ, or its disabled,
545          * we shouldn't process the IRQ. Mark it pending, handle
546          * the necessary masking and go out
547          */
548         if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
549                      irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
550                 if (!irq_check_poll(desc)) {
551                         desc->istate |= IRQS_PENDING;
552                         mask_ack_irq(desc);
553                         goto out_unlock;
554                 }
555         }
556         kstat_incr_irqs_this_cpu(irq, desc);
557
558         /* Start handling the irq */
559         desc->irq_data.chip->irq_ack(&desc->irq_data);
560
561         do {
562                 if (unlikely(!desc->action)) {
563                         mask_irq(desc);
564                         goto out_unlock;
565                 }
566
567                 /*
568                  * When another irq arrived while we were handling
569                  * one, we could have masked the irq.
570                  * Renable it, if it was not disabled in meantime.
571                  */
572                 if (unlikely(desc->istate & IRQS_PENDING)) {
573                         if (!irqd_irq_disabled(&desc->irq_data) &&
574                             irqd_irq_masked(&desc->irq_data))
575                                 unmask_irq(desc);
576                 }
577
578                 handle_irq_event(desc);
579
580         } while ((desc->istate & IRQS_PENDING) &&
581                  !irqd_irq_disabled(&desc->irq_data));
582
583 out_unlock:
584         raw_spin_unlock(&desc->lock);
585 }
586 EXPORT_SYMBOL(handle_edge_irq);
587
588 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
589 /**
590  *      handle_edge_eoi_irq - edge eoi type IRQ handler
591  *      @irq:   the interrupt number
592  *      @desc:  the interrupt description structure for this irq
593  *
594  * Similar as the above handle_edge_irq, but using eoi and w/o the
595  * mask/unmask logic.
596  */
597 void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
598 {
599         struct irq_chip *chip = irq_desc_get_chip(desc);
600
601         raw_spin_lock(&desc->lock);
602
603         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
604         /*
605          * If we're currently running this IRQ, or its disabled,
606          * we shouldn't process the IRQ. Mark it pending, handle
607          * the necessary masking and go out
608          */
609         if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
610                      irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
611                 if (!irq_check_poll(desc)) {
612                         desc->istate |= IRQS_PENDING;
613                         goto out_eoi;
614                 }
615         }
616         kstat_incr_irqs_this_cpu(irq, desc);
617
618         do {
619                 if (unlikely(!desc->action))
620                         goto out_eoi;
621
622                 handle_irq_event(desc);
623
624         } while ((desc->istate & IRQS_PENDING) &&
625                  !irqd_irq_disabled(&desc->irq_data));
626
627 out_eoi:
628         chip->irq_eoi(&desc->irq_data);
629         raw_spin_unlock(&desc->lock);
630 }
631 #endif
632
633 /**
634  *      handle_percpu_irq - Per CPU local irq handler
635  *      @irq:   the interrupt number
636  *      @desc:  the interrupt description structure for this irq
637  *
638  *      Per CPU interrupts on SMP machines without locking requirements
639  */
640 void
641 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
642 {
643         struct irq_chip *chip = irq_desc_get_chip(desc);
644
645         kstat_incr_irqs_this_cpu(irq, desc);
646
647         if (chip->irq_ack)
648                 chip->irq_ack(&desc->irq_data);
649
650         handle_irq_event_percpu(desc, desc->action);
651
652         if (chip->irq_eoi)
653                 chip->irq_eoi(&desc->irq_data);
654 }
655
656 /**
657  * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
658  * @irq:        the interrupt number
659  * @desc:       the interrupt description structure for this irq
660  *
661  * Per CPU interrupts on SMP machines without locking requirements. Same as
662  * handle_percpu_irq() above but with the following extras:
663  *
664  * action->percpu_dev_id is a pointer to percpu variables which
665  * contain the real device id for the cpu on which this handler is
666  * called
667  */
668 void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
669 {
670         struct irq_chip *chip = irq_desc_get_chip(desc);
671         struct irqaction *action = desc->action;
672         void *dev_id = __this_cpu_ptr(action->percpu_dev_id);
673         irqreturn_t res;
674
675         kstat_incr_irqs_this_cpu(irq, desc);
676
677         if (chip->irq_ack)
678                 chip->irq_ack(&desc->irq_data);
679
680         trace_irq_handler_entry(irq, action);
681         res = action->handler(irq, dev_id);
682         trace_irq_handler_exit(irq, action, res);
683
684         if (chip->irq_eoi)
685                 chip->irq_eoi(&desc->irq_data);
686 }
687
688 void
689 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
690                   const char *name)
691 {
692         unsigned long flags;
693         struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
694
695         if (!desc)
696                 return;
697
698         if (!handle) {
699                 handle = handle_bad_irq;
700         } else {
701                 if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
702                         goto out;
703         }
704
705         /* Uninstall? */
706         if (handle == handle_bad_irq) {
707                 if (desc->irq_data.chip != &no_irq_chip)
708                         mask_ack_irq(desc);
709                 irq_state_set_disabled(desc);
710                 desc->depth = 1;
711         }
712         desc->handle_irq = handle;
713         desc->name = name;
714
715         if (handle != handle_bad_irq && is_chained) {
716                 irq_settings_set_noprobe(desc);
717                 irq_settings_set_norequest(desc);
718                 irq_settings_set_nothread(desc);
719                 irq_startup(desc, true);
720         }
721 out:
722         irq_put_desc_busunlock(desc, flags);
723 }
724 EXPORT_SYMBOL_GPL(__irq_set_handler);
725
726 void
727 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
728                               irq_flow_handler_t handle, const char *name)
729 {
730         irq_set_chip(irq, chip);
731         __irq_set_handler(irq, handle, 0, name);
732 }
733 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
734
735 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
736 {
737         unsigned long flags;
738         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
739
740         if (!desc)
741                 return;
742         irq_settings_clr_and_set(desc, clr, set);
743
744         irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
745                    IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
746         if (irq_settings_has_no_balance_set(desc))
747                 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
748         if (irq_settings_is_per_cpu(desc))
749                 irqd_set(&desc->irq_data, IRQD_PER_CPU);
750         if (irq_settings_can_move_pcntxt(desc))
751                 irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
752         if (irq_settings_is_level(desc))
753                 irqd_set(&desc->irq_data, IRQD_LEVEL);
754
755         irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
756
757         irq_put_desc_unlock(desc, flags);
758 }
759 EXPORT_SYMBOL_GPL(irq_modify_status);
760
761 /**
762  *      irq_cpu_online - Invoke all irq_cpu_online functions.
763  *
764  *      Iterate through all irqs and invoke the chip.irq_cpu_online()
765  *      for each.
766  */
767 void irq_cpu_online(void)
768 {
769         struct irq_desc *desc;
770         struct irq_chip *chip;
771         unsigned long flags;
772         unsigned int irq;
773
774         for_each_active_irq(irq) {
775                 desc = irq_to_desc(irq);
776                 if (!desc)
777                         continue;
778
779                 raw_spin_lock_irqsave(&desc->lock, flags);
780
781                 chip = irq_data_get_irq_chip(&desc->irq_data);
782                 if (chip && chip->irq_cpu_online &&
783                     (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
784                      !irqd_irq_disabled(&desc->irq_data)))
785                         chip->irq_cpu_online(&desc->irq_data);
786
787                 raw_spin_unlock_irqrestore(&desc->lock, flags);
788         }
789 }
790
791 /**
792  *      irq_cpu_offline - Invoke all irq_cpu_offline functions.
793  *
794  *      Iterate through all irqs and invoke the chip.irq_cpu_offline()
795  *      for each.
796  */
797 void irq_cpu_offline(void)
798 {
799         struct irq_desc *desc;
800         struct irq_chip *chip;
801         unsigned long flags;
802         unsigned int irq;
803
804         for_each_active_irq(irq) {
805                 desc = irq_to_desc(irq);
806                 if (!desc)
807                         continue;
808
809                 raw_spin_lock_irqsave(&desc->lock, flags);
810
811                 chip = irq_data_get_irq_chip(&desc->irq_data);
812                 if (chip && chip->irq_cpu_offline &&
813                     (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
814                      !irqd_irq_disabled(&desc->irq_data)))
815                         chip->irq_cpu_offline(&desc->irq_data);
816
817                 raw_spin_unlock_irqrestore(&desc->lock, flags);
818         }
819 }