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1da177e4
LT
1/* interrupt.h */
2#ifndef _LINUX_INTERRUPT_H
3#define _LINUX_INTERRUPT_H
4
1da177e4
LT
5#include <linux/kernel.h>
6#include <linux/linkage.h>
7#include <linux/bitops.h>
8#include <linux/preempt.h>
9#include <linux/cpumask.h>
908dcecd 10#include <linux/irqreturn.h>
dd3a1db9 11#include <linux/irqnr.h>
1da177e4 12#include <linux/hardirq.h>
de30a2b3 13#include <linux/irqflags.h>
9ba5f005 14#include <linux/hrtimer.h>
cd7eab44
BH
15#include <linux/kref.h>
16#include <linux/workqueue.h>
0ebb26e7 17
60063497 18#include <linux/atomic.h>
1da177e4 19#include <asm/ptrace.h>
7d65f4a6 20#include <asm/irq.h>
1da177e4 21
6e213616
TG
22/*
23 * These correspond to the IORESOURCE_IRQ_* defines in
24 * linux/ioport.h to select the interrupt line behaviour. When
25 * requesting an interrupt without specifying a IRQF_TRIGGER, the
26 * setting should be assumed to be "as already configured", which
27 * may be as per machine or firmware initialisation.
28 */
29#define IRQF_TRIGGER_NONE 0x00000000
30#define IRQF_TRIGGER_RISING 0x00000001
31#define IRQF_TRIGGER_FALLING 0x00000002
32#define IRQF_TRIGGER_HIGH 0x00000004
33#define IRQF_TRIGGER_LOW 0x00000008
34#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
35 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
36#define IRQF_TRIGGER_PROBE 0x00000010
37
38/*
39 * These flags used only by the kernel as part of the
40 * irq handling routines.
41 *
6932bf37
TG
42 * IRQF_DISABLED - keep irqs disabled when calling the action handler.
43 * DEPRECATED. This flag is a NOOP and scheduled to be removed
6e213616
TG
44 * IRQF_SHARED - allow sharing the irq among several devices
45 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
46 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
950f4427
TG
47 * IRQF_PERCPU - Interrupt is per cpu
48 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
d85a60d8
BW
49 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
50 * registered first in an shared interrupt is considered for
51 * performance reasons)
b25c340c
TG
52 * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
53 * Used by threaded interrupts which need to keep the
54 * irq line disabled until the threaded handler has been run.
685fd0b4 55 * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
dc5f219e 56 * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
0c4602ff 57 * IRQF_NO_THREAD - Interrupt cannot be threaded
9bab0b7f
IC
58 * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
59 * resume time.
6e213616
TG
60 */
61#define IRQF_DISABLED 0x00000020
6e213616
TG
62#define IRQF_SHARED 0x00000080
63#define IRQF_PROBE_SHARED 0x00000100
685fd0b4 64#define __IRQF_TIMER 0x00000200
284c6680 65#define IRQF_PERCPU 0x00000400
950f4427 66#define IRQF_NOBALANCING 0x00000800
d85a60d8 67#define IRQF_IRQPOLL 0x00001000
b25c340c 68#define IRQF_ONESHOT 0x00002000
685fd0b4 69#define IRQF_NO_SUSPEND 0x00004000
dc5f219e 70#define IRQF_FORCE_RESUME 0x00008000
0c4602ff 71#define IRQF_NO_THREAD 0x00010000
9bab0b7f 72#define IRQF_EARLY_RESUME 0x00020000
685fd0b4 73
0c4602ff 74#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
3aa551c9 75
b4e6b097 76/*
ae731f8d
MZ
77 * These values can be returned by request_any_context_irq() and
78 * describe the context the interrupt will be run in.
79 *
80 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
81 * IRQC_IS_NESTED - interrupt runs in a nested threaded context
82 */
83enum {
84 IRQC_IS_HARDIRQ = 0,
85 IRQC_IS_NESTED,
86};
87
7d12e780 88typedef irqreturn_t (*irq_handler_t)(int, void *);
da482792 89
a9d0a1a3
TG
90/**
91 * struct irqaction - per interrupt action descriptor
92 * @handler: interrupt handler function
a9d0a1a3
TG
93 * @name: name of the device
94 * @dev_id: cookie to identify the device
31d9d9b6 95 * @percpu_dev_id: cookie to identify the device
a9d0a1a3
TG
96 * @next: pointer to the next irqaction for shared interrupts
97 * @irq: interrupt number
c0ecaa06 98 * @flags: flags (see IRQF_* above)
25985edc 99 * @thread_fn: interrupt handler function for threaded interrupts
3aa551c9
TG
100 * @thread: thread pointer for threaded interrupts
101 * @thread_flags: flags related to @thread
b5faba21 102 * @thread_mask: bitmask for keeping track of @thread activity
c0ecaa06 103 * @dir: pointer to the proc/irq/NN/name entry
a9d0a1a3 104 */
1da177e4 105struct irqaction {
31d9d9b6 106 irq_handler_t handler;
31d9d9b6
MZ
107 void *dev_id;
108 void __percpu *percpu_dev_id;
109 struct irqaction *next;
31d9d9b6
MZ
110 irq_handler_t thread_fn;
111 struct task_struct *thread;
c0ecaa06
TG
112 unsigned int irq;
113 unsigned int flags;
31d9d9b6
MZ
114 unsigned long thread_flags;
115 unsigned long thread_mask;
116 const char *name;
117 struct proc_dir_entry *dir;
f6cd2477 118} ____cacheline_internodealigned_in_smp;
1da177e4 119
7d12e780 120extern irqreturn_t no_action(int cpl, void *dev_id);
3aa551c9
TG
121
122extern int __must_check
123request_threaded_irq(unsigned int irq, irq_handler_t handler,
124 irq_handler_t thread_fn,
125 unsigned long flags, const char *name, void *dev);
126
127static inline int __must_check
128request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
129 const char *name, void *dev)
130{
131 return request_threaded_irq(irq, handler, NULL, flags, name, dev);
132}
133
ae731f8d
MZ
134extern int __must_check
135request_any_context_irq(unsigned int irq, irq_handler_t handler,
136 unsigned long flags, const char *name, void *dev_id);
137
31d9d9b6
MZ
138extern int __must_check
139request_percpu_irq(unsigned int irq, irq_handler_t handler,
140 const char *devname, void __percpu *percpu_dev_id);
3aa551c9 141
1da177e4 142extern void free_irq(unsigned int, void *);
31d9d9b6 143extern void free_percpu_irq(unsigned int, void __percpu *);
1da177e4 144
0af3678f
AV
145struct device;
146
935bd5b9
AV
147extern int __must_check
148devm_request_threaded_irq(struct device *dev, unsigned int irq,
149 irq_handler_t handler, irq_handler_t thread_fn,
150 unsigned long irqflags, const char *devname,
151 void *dev_id);
152
153static inline int __must_check
154devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
155 unsigned long irqflags, const char *devname, void *dev_id)
156{
157 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
158 devname, dev_id);
159}
160
0668d306
SB
161extern int __must_check
162devm_request_any_context_irq(struct device *dev, unsigned int irq,
163 irq_handler_t handler, unsigned long irqflags,
164 const char *devname, void *dev_id);
165
9ac7849e
TH
166extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
167
d7e9629d
IM
168/*
169 * On lockdep we dont want to enable hardirqs in hardirq
170 * context. Use local_irq_enable_in_hardirq() to annotate
171 * kernel code that has to do this nevertheless (pretty much
172 * the only valid case is for old/broken hardware that is
173 * insanely slow).
174 *
175 * NOTE: in theory this might break fragile code that relies
176 * on hardirq delivery - in practice we dont seem to have such
177 * places left. So the only effect should be slightly increased
178 * irqs-off latencies.
179 */
180#ifdef CONFIG_LOCKDEP
181# define local_irq_enable_in_hardirq() do { } while (0)
182#else
183# define local_irq_enable_in_hardirq() local_irq_enable()
184#endif
1da177e4 185
1da177e4
LT
186extern void disable_irq_nosync(unsigned int irq);
187extern void disable_irq(unsigned int irq);
31d9d9b6 188extern void disable_percpu_irq(unsigned int irq);
1da177e4 189extern void enable_irq(unsigned int irq);
1e7c5fd2 190extern void enable_percpu_irq(unsigned int irq, unsigned int type);
a92444c6 191extern void irq_wake_thread(unsigned int irq, void *dev_id);
ba9a2331 192
0a0c5168
RW
193/* The following three functions are for the core kernel use only. */
194extern void suspend_device_irqs(void);
195extern void resume_device_irqs(void);
0a0c5168 196
f0ba3d05
EP
197/**
198 * struct irq_affinity_notify - context for notification of IRQ affinity changes
199 * @irq: Interrupt to which notification applies
200 * @kref: Reference count, for internal use
201 * @work: Work item, for internal use
202 * @notify: Function to be called on change. This will be
203 * called in process context.
204 * @release: Function to be called on release. This will be
205 * called in process context. Once registered, the
206 * structure must only be freed when this function is
207 * called or later.
208 */
209struct irq_affinity_notify {
210 unsigned int irq;
211 struct kref kref;
212 struct work_struct work;
213 void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
214 void (*release)(struct kref *ref);
215};
216
0244ad00 217#if defined(CONFIG_SMP)
d7b90689 218
d036e67b 219extern cpumask_var_t irq_default_affinity;
18404756 220
01f8fa4f
TG
221/* Internal implementation. Use the helpers below */
222extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
223 bool force);
224
225/**
226 * irq_set_affinity - Set the irq affinity of a given irq
227 * @irq: Interrupt to set affinity
def5f127 228 * @cpumask: cpumask
01f8fa4f
TG
229 *
230 * Fails if cpumask does not contain an online CPU
231 */
232static inline int
233irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
234{
235 return __irq_set_affinity(irq, cpumask, false);
236}
237
238/**
239 * irq_force_affinity - Force the irq affinity of a given irq
240 * @irq: Interrupt to set affinity
def5f127 241 * @cpumask: cpumask
01f8fa4f
TG
242 *
243 * Same as irq_set_affinity, but without checking the mask against
244 * online cpus.
245 *
246 * Solely for low level cpu hotplug code, where we need to make per
247 * cpu interrupts affine before the cpu becomes online.
248 */
249static inline int
250irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
251{
252 return __irq_set_affinity(irq, cpumask, true);
253}
254
d7b90689 255extern int irq_can_set_affinity(unsigned int irq);
18404756 256extern int irq_select_affinity(unsigned int irq);
d7b90689 257
e7a297b0 258extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
cd7eab44 259
cd7eab44
BH
260extern int
261irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
262
d7b90689
RK
263#else /* CONFIG_SMP */
264
0de26520 265static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
d7b90689
RK
266{
267 return -EINVAL;
268}
269
4c88d7f9
AB
270static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
271{
272 return 0;
273}
274
d7b90689
RK
275static inline int irq_can_set_affinity(unsigned int irq)
276{
277 return 0;
278}
279
18404756
MK
280static inline int irq_select_affinity(unsigned int irq) { return 0; }
281
e7a297b0 282static inline int irq_set_affinity_hint(unsigned int irq,
cd7eab44 283 const struct cpumask *m)
e7a297b0
PWJ
284{
285 return -EINVAL;
286}
f0ba3d05
EP
287
288static inline int
289irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
290{
291 return 0;
292}
0244ad00 293#endif /* CONFIG_SMP */
d7b90689 294
c01d403b
IM
295/*
296 * Special lockdep variants of irq disabling/enabling.
297 * These should be used for locking constructs that
298 * know that a particular irq context which is disabled,
299 * and which is the only irq-context user of a lock,
300 * that it's safe to take the lock in the irq-disabled
301 * section without disabling hardirqs.
302 *
303 * On !CONFIG_LOCKDEP they are equivalent to the normal
304 * irq disable/enable methods.
305 */
306static inline void disable_irq_nosync_lockdep(unsigned int irq)
307{
308 disable_irq_nosync(irq);
309#ifdef CONFIG_LOCKDEP
310 local_irq_disable();
311#endif
312}
313
e8106b94
AV
314static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
315{
316 disable_irq_nosync(irq);
317#ifdef CONFIG_LOCKDEP
318 local_irq_save(*flags);
319#endif
320}
321
c01d403b
IM
322static inline void disable_irq_lockdep(unsigned int irq)
323{
324 disable_irq(irq);
325#ifdef CONFIG_LOCKDEP
326 local_irq_disable();
327#endif
328}
329
330static inline void enable_irq_lockdep(unsigned int irq)
331{
332#ifdef CONFIG_LOCKDEP
333 local_irq_enable();
334#endif
335 enable_irq(irq);
336}
337
e8106b94
AV
338static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
339{
340#ifdef CONFIG_LOCKDEP
341 local_irq_restore(*flags);
342#endif
343 enable_irq(irq);
344}
345
ba9a2331 346/* IRQ wakeup (PM) control: */
a0cd9ca2
TG
347extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
348
ba9a2331
TG
349static inline int enable_irq_wake(unsigned int irq)
350{
a0cd9ca2 351 return irq_set_irq_wake(irq, 1);
ba9a2331
TG
352}
353
354static inline int disable_irq_wake(unsigned int irq)
355{
a0cd9ca2 356 return irq_set_irq_wake(irq, 0);
ba9a2331
TG
357}
358
8d32a307
TG
359
360#ifdef CONFIG_IRQ_FORCED_THREADING
361extern bool force_irqthreads;
362#else
363#define force_irqthreads (0)
364#endif
365
3f74478b
AK
366#ifndef __ARCH_SET_SOFTIRQ_PENDING
367#define set_softirq_pending(x) (local_softirq_pending() = (x))
368#define or_softirq_pending(x) (local_softirq_pending() |= (x))
369#endif
370
2d3fbbb3
BH
371/* Some architectures might implement lazy enabling/disabling of
372 * interrupts. In some cases, such as stop_machine, we might want
373 * to ensure that after a local_irq_disable(), interrupts have
374 * really been disabled in hardware. Such architectures need to
375 * implement the following hook.
376 */
377#ifndef hard_irq_disable
378#define hard_irq_disable() do { } while(0)
379#endif
380
1da177e4
LT
381/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
382 frequency threaded job scheduling. For almost all the purposes
383 tasklets are more than enough. F.e. all serial device BHs et
384 al. should be converted to tasklets, not to softirqs.
385 */
386
387enum
388{
389 HI_SOFTIRQ=0,
390 TIMER_SOFTIRQ,
391 NET_TX_SOFTIRQ,
392 NET_RX_SOFTIRQ,
ff856bad 393 BLOCK_SOFTIRQ,
5e605b64 394 BLOCK_IOPOLL_SOFTIRQ,
c9819f45
CL
395 TASKLET_SOFTIRQ,
396 SCHED_SOFTIRQ,
a6037b61 397 HRTIMER_SOFTIRQ,
09223371 398 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
978b0116
AD
399
400 NR_SOFTIRQS
1da177e4
LT
401};
402
803b0eba
PM
403#define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
404
5d592b44
JB
405/* map softirq index to softirq name. update 'softirq_to_name' in
406 * kernel/softirq.c when adding a new softirq.
407 */
ce85b4f2 408extern const char * const softirq_to_name[NR_SOFTIRQS];
5d592b44 409
1da177e4
LT
410/* softirq mask and active fields moved to irq_cpustat_t in
411 * asm/hardirq.h to get better cache usage. KAO
412 */
413
414struct softirq_action
415{
416 void (*action)(struct softirq_action *);
1da177e4
LT
417};
418
419asmlinkage void do_softirq(void);
eb0f1c44 420asmlinkage void __do_softirq(void);
7d65f4a6
FW
421
422#ifdef __ARCH_HAS_DO_SOFTIRQ
423void do_softirq_own_stack(void);
424#else
425static inline void do_softirq_own_stack(void)
426{
427 __do_softirq();
428}
429#endif
430
962cf36c 431extern void open_softirq(int nr, void (*action)(struct softirq_action *));
1da177e4 432extern void softirq_init(void);
f069686e 433extern void __raise_softirq_irqoff(unsigned int nr);
2bf2160d 434
b3c97528
HH
435extern void raise_softirq_irqoff(unsigned int nr);
436extern void raise_softirq(unsigned int nr);
1da177e4 437
4dd53d89
VP
438DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
439
440static inline struct task_struct *this_cpu_ksoftirqd(void)
441{
442 return this_cpu_read(ksoftirqd);
443}
444
1da177e4
LT
445/* Tasklets --- multithreaded analogue of BHs.
446
447 Main feature differing them of generic softirqs: tasklet
448 is running only on one CPU simultaneously.
449
450 Main feature differing them of BHs: different tasklets
451 may be run simultaneously on different CPUs.
452
453 Properties:
454 * If tasklet_schedule() is called, then tasklet is guaranteed
455 to be executed on some cpu at least once after this.
25985edc 456 * If the tasklet is already scheduled, but its execution is still not
1da177e4
LT
457 started, it will be executed only once.
458 * If this tasklet is already running on another CPU (or schedule is called
459 from tasklet itself), it is rescheduled for later.
460 * Tasklet is strictly serialized wrt itself, but not
461 wrt another tasklets. If client needs some intertask synchronization,
462 he makes it with spinlocks.
463 */
464
465struct tasklet_struct
466{
467 struct tasklet_struct *next;
468 unsigned long state;
469 atomic_t count;
470 void (*func)(unsigned long);
471 unsigned long data;
472};
473
474#define DECLARE_TASKLET(name, func, data) \
475struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
476
477#define DECLARE_TASKLET_DISABLED(name, func, data) \
478struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
479
480
481enum
482{
483 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
484 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
485};
486
487#ifdef CONFIG_SMP
488static inline int tasklet_trylock(struct tasklet_struct *t)
489{
490 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
491}
492
493static inline void tasklet_unlock(struct tasklet_struct *t)
494{
4e857c58 495 smp_mb__before_atomic();
1da177e4
LT
496 clear_bit(TASKLET_STATE_RUN, &(t)->state);
497}
498
499static inline void tasklet_unlock_wait(struct tasklet_struct *t)
500{
501 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
502}
503#else
504#define tasklet_trylock(t) 1
505#define tasklet_unlock_wait(t) do { } while (0)
506#define tasklet_unlock(t) do { } while (0)
507#endif
508
b3c97528 509extern void __tasklet_schedule(struct tasklet_struct *t);
1da177e4
LT
510
511static inline void tasklet_schedule(struct tasklet_struct *t)
512{
513 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
514 __tasklet_schedule(t);
515}
516
b3c97528 517extern void __tasklet_hi_schedule(struct tasklet_struct *t);
1da177e4
LT
518
519static inline void tasklet_hi_schedule(struct tasklet_struct *t)
520{
521 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
522 __tasklet_hi_schedule(t);
523}
524
7c692cba
VN
525extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
526
527/*
528 * This version avoids touching any other tasklets. Needed for kmemcheck
529 * in order not to take any page faults while enqueueing this tasklet;
530 * consider VERY carefully whether you really need this or
531 * tasklet_hi_schedule()...
532 */
533static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
534{
535 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
536 __tasklet_hi_schedule_first(t);
537}
538
1da177e4
LT
539
540static inline void tasklet_disable_nosync(struct tasklet_struct *t)
541{
542 atomic_inc(&t->count);
4e857c58 543 smp_mb__after_atomic();
1da177e4
LT
544}
545
546static inline void tasklet_disable(struct tasklet_struct *t)
547{
548 tasklet_disable_nosync(t);
549 tasklet_unlock_wait(t);
550 smp_mb();
551}
552
553static inline void tasklet_enable(struct tasklet_struct *t)
554{
4e857c58 555 smp_mb__before_atomic();
1da177e4
LT
556 atomic_dec(&t->count);
557}
558
559static inline void tasklet_hi_enable(struct tasklet_struct *t)
560{
4e857c58 561 smp_mb__before_atomic();
1da177e4
LT
562 atomic_dec(&t->count);
563}
564
565extern void tasklet_kill(struct tasklet_struct *t);
566extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
567extern void tasklet_init(struct tasklet_struct *t,
568 void (*func)(unsigned long), unsigned long data);
569
9ba5f005
PZ
570struct tasklet_hrtimer {
571 struct hrtimer timer;
572 struct tasklet_struct tasklet;
573 enum hrtimer_restart (*function)(struct hrtimer *);
574};
575
576extern void
577tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
578 enum hrtimer_restart (*function)(struct hrtimer *),
579 clockid_t which_clock, enum hrtimer_mode mode);
580
581static inline
582int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
583 const enum hrtimer_mode mode)
584{
585 return hrtimer_start(&ttimer->timer, time, mode);
586}
587
588static inline
589void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
590{
591 hrtimer_cancel(&ttimer->timer);
592 tasklet_kill(&ttimer->tasklet);
593}
594
1da177e4
LT
595/*
596 * Autoprobing for irqs:
597 *
598 * probe_irq_on() and probe_irq_off() provide robust primitives
599 * for accurate IRQ probing during kernel initialization. They are
600 * reasonably simple to use, are not "fooled" by spurious interrupts,
601 * and, unlike other attempts at IRQ probing, they do not get hung on
602 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
603 *
604 * For reasonably foolproof probing, use them as follows:
605 *
606 * 1. clear and/or mask the device's internal interrupt.
607 * 2. sti();
608 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
609 * 4. enable the device and cause it to trigger an interrupt.
610 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
611 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
612 * 7. service the device to clear its pending interrupt.
613 * 8. loop again if paranoia is required.
614 *
615 * probe_irq_on() returns a mask of allocated irq's.
616 *
617 * probe_irq_off() takes the mask as a parameter,
618 * and returns the irq number which occurred,
619 * or zero if none occurred, or a negative irq number
620 * if more than one irq occurred.
621 */
622
0244ad00 623#if !defined(CONFIG_GENERIC_IRQ_PROBE)
1da177e4
LT
624static inline unsigned long probe_irq_on(void)
625{
626 return 0;
627}
628static inline int probe_irq_off(unsigned long val)
629{
630 return 0;
631}
632static inline unsigned int probe_irq_mask(unsigned long val)
633{
634 return 0;
635}
636#else
637extern unsigned long probe_irq_on(void); /* returns 0 on failure */
638extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
639extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
640#endif
641
6168a702
AM
642#ifdef CONFIG_PROC_FS
643/* Initialize /proc/irq/ */
644extern void init_irq_proc(void);
645#else
646static inline void init_irq_proc(void)
647{
648}
649#endif
650
d43c36dc 651struct seq_file;
f74596d0 652int show_interrupts(struct seq_file *p, void *v);
c78b9b65 653int arch_show_interrupts(struct seq_file *p, int prec);
f74596d0 654
43a25632 655extern int early_irq_init(void);
4a046d17 656extern int arch_probe_nr_irqs(void);
43a25632 657extern int arch_early_irq_init(void);
43a25632 658
1da177e4 659#endif