include/linux/interrupt.h

   1 /* interrupt.h */
   2 #ifndef _LINUX_INTERRUPT_H
   3 #define _LINUX_INTERRUPT_H
   4
   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>
  10 #include <linux/irqreturn.h>
  11 #include <linux/irqnr.h>
  12 #include <linux/hardirq.h>
  13 #include <linux/irqflags.h>
  14 #include <linux/hrtimer.h>
  15 #include <linux/kref.h>
  16 #include <linux/workqueue.h>
  17
  18 #include <linux/atomic.h>
  19 #include <asm/ptrace.h>
  20
  21 /*
  22  * These correspond to the IORESOURCE_IRQ_* defines in
  23  * linux/ioport.h to select the interrupt line behaviour.  When
  24  * requesting an interrupt without specifying a IRQF_TRIGGER, the
  25  * setting should be assumed to be "as already configured", which
  26  * may be as per machine or firmware initialisation.
  27  */
  28 #define IRQF_TRIGGER_NONE       0x00000000
  29 #define IRQF_TRIGGER_RISING     0x00000001
  30 #define IRQF_TRIGGER_FALLING    0x00000002
  31 #define IRQF_TRIGGER_HIGH       0x00000004
  32 #define IRQF_TRIGGER_LOW        0x00000008
  33 #define IRQF_TRIGGER_MASK       (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
  34                                  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
  35 #define IRQF_TRIGGER_PROBE      0x00000010
  36
  37 /*
  38  * These flags used only by the kernel as part of the
  39  * irq handling routines.
  40  *
  41  * IRQF_DISABLED - keep irqs disabled when calling the action handler.
  42  *                 DEPRECATED. This flag is a NOOP and scheduled to be removed
  43  * IRQF_SHARED - allow sharing the irq among several devices
  44  * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
  45  * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
  46  * IRQF_PERCPU - Interrupt is per cpu
  47  * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
  48  * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
  49  *                registered first in an shared interrupt is considered for
  50  *                performance reasons)
  51  * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
  52  *                Used by threaded interrupts which need to keep the
  53  *                irq line disabled until the threaded handler has been run.
  54  * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
  55  * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
  56  * IRQF_NO_THREAD - Interrupt cannot be threaded
  57  * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
  58  *                resume time.
  59  */
  60 #define IRQF_DISABLED           0x00000020
  61 #define IRQF_SHARED             0x00000080
  62 #define IRQF_PROBE_SHARED       0x00000100
  63 #define __IRQF_TIMER            0x00000200
  64 #define IRQF_PERCPU             0x00000400
  65 #define IRQF_NOBALANCING        0x00000800
  66 #define IRQF_IRQPOLL            0x00001000
  67 #define IRQF_ONESHOT            0x00002000
  68 #define IRQF_NO_SUSPEND         0x00004000
  69 #define IRQF_FORCE_RESUME       0x00008000
  70 #define IRQF_NO_THREAD          0x00010000
  71 #define IRQF_EARLY_RESUME       0x00020000
  72
  73 #define IRQF_TIMER              (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
  74
  75 /*
  76  * These values can be returned by request_any_context_irq() and
  77  * describe the context the interrupt will be run in.
  78  *
  79  * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
  80  * IRQC_IS_NESTED - interrupt runs in a nested threaded context
  81  */
  82 enum {
  83         IRQC_IS_HARDIRQ = 0,
  84         IRQC_IS_NESTED,
  85 };
  86
  87 typedef irqreturn_t (*irq_handler_t)(int, void *);
  88
  89 /**
  90  * struct irqaction - per interrupt action descriptor
  91  * @handler:    interrupt handler function
  92  * @name:       name of the device
  93  * @dev_id:     cookie to identify the device
  94  * @percpu_dev_id:      cookie to identify the device
  95  * @next:       pointer to the next irqaction for shared interrupts
  96  * @irq:        interrupt number
  97  * @flags:      flags (see IRQF_* above)
  98  * @thread_fn:  interrupt handler function for threaded interrupts
  99  * @thread:     thread pointer for threaded interrupts
 100  * @thread_flags:       flags related to @thread
 101  * @thread_mask:        bitmask for keeping track of @thread activity
 102  * @dir:        pointer to the proc/irq/NN/name entry
 103  */
 104 struct irqaction {
 105         irq_handler_t           handler;
 106         void                    *dev_id;
 107         void __percpu           *percpu_dev_id;
 108         struct irqaction        *next;
 109         irq_handler_t           thread_fn;
 110         struct task_struct      *thread;
 111         unsigned int            irq;
 112         unsigned int            flags;
 113         unsigned long           thread_flags;
 114         unsigned long           thread_mask;
 115         const char              *name;
 116         struct proc_dir_entry   *dir;
 117 } ____cacheline_internodealigned_in_smp;
 118
 119 extern irqreturn_t no_action(int cpl, void *dev_id);
 120
 121 #ifdef CONFIG_GENERIC_HARDIRQS
 122 extern int __must_check
 123 request_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
 127 static inline int __must_check
 128 request_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
 134 extern int __must_check
 135 request_any_context_irq(unsigned int irq, irq_handler_t handler,
 136                         unsigned long flags, const char *name, void *dev_id);
 137
 138 extern int __must_check
 139 request_percpu_irq(unsigned int irq, irq_handler_t handler,
 140                    const char *devname, void __percpu *percpu_dev_id);
 141 #else
 142
 143 extern int __must_check
 144 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
 145             const char *name, void *dev);
 146
 147 /*
 148  * Special function to avoid ifdeffery in kernel/irq/devres.c which
 149  * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
 150  * m68k). I really love these $@%#!* obvious Makefile references:
 151  * ../../../kernel/irq/devres.o
 152  */
 153 static inline int __must_check
 154 request_threaded_irq(unsigned int irq, irq_handler_t handler,
 155                      irq_handler_t thread_fn,
 156                      unsigned long flags, const char *name, void *dev)
 157 {
 158         return request_irq(irq, handler, flags, name, dev);
 159 }
 160
 161 static inline int __must_check
 162 request_any_context_irq(unsigned int irq, irq_handler_t handler,
 163                         unsigned long flags, const char *name, void *dev_id)
 164 {
 165         return request_irq(irq, handler, flags, name, dev_id);
 166 }
 167
 168 static inline int __must_check
 169 request_percpu_irq(unsigned int irq, irq_handler_t handler,
 170                    const char *devname, void __percpu *percpu_dev_id)
 171 {
 172         return request_irq(irq, handler, 0, devname, percpu_dev_id);
 173 }
 174 #endif
 175
 176 extern void free_irq(unsigned int, void *);
 177 extern void free_percpu_irq(unsigned int, void __percpu *);
 178
 179 struct device;
 180
 181 extern int __must_check
 182 devm_request_threaded_irq(struct device *dev, unsigned int irq,
 183                           irq_handler_t handler, irq_handler_t thread_fn,
 184                           unsigned long irqflags, const char *devname,
 185                           void *dev_id);
 186
 187 static inline int __must_check
 188 devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
 189                  unsigned long irqflags, const char *devname, void *dev_id)
 190 {
 191         return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
 192                                          devname, dev_id);
 193 }
 194
 195 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
 196
 197 /*
 198  * On lockdep we dont want to enable hardirqs in hardirq
 199  * context. Use local_irq_enable_in_hardirq() to annotate
 200  * kernel code that has to do this nevertheless (pretty much
 201  * the only valid case is for old/broken hardware that is
 202  * insanely slow).
 203  *
 204  * NOTE: in theory this might break fragile code that relies
 205  * on hardirq delivery - in practice we dont seem to have such
 206  * places left. So the only effect should be slightly increased
 207  * irqs-off latencies.
 208  */
 209 #ifdef CONFIG_LOCKDEP
 210 # define local_irq_enable_in_hardirq()  do { } while (0)
 211 #else
 212 # define local_irq_enable_in_hardirq()  local_irq_enable()
 213 #endif
 214
 215 extern void disable_irq_nosync(unsigned int irq);
 216 extern void disable_irq(unsigned int irq);
 217 extern void disable_percpu_irq(unsigned int irq);
 218 extern void enable_irq(unsigned int irq);
 219 extern void enable_percpu_irq(unsigned int irq, unsigned int type);
 220
 221 /* The following three functions are for the core kernel use only. */
 222 #ifdef CONFIG_GENERIC_HARDIRQS
 223 extern void suspend_device_irqs(void);
 224 extern void resume_device_irqs(void);
 225 #ifdef CONFIG_PM_SLEEP
 226 extern int check_wakeup_irqs(void);
 227 #else
 228 static inline int check_wakeup_irqs(void) { return 0; }
 229 #endif
 230 #else
 231 static inline void suspend_device_irqs(void) { };
 232 static inline void resume_device_irqs(void) { };
 233 static inline int check_wakeup_irqs(void) { return 0; }
 234 #endif
 235
 236 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
 237
 238 extern cpumask_var_t irq_default_affinity;
 239
 240 /* Internal implementation. Use the helpers below */
 241 extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
 242                               bool force);
 243
 244 /**
 245  * irq_set_affinity - Set the irq affinity of a given irq
 246  * @irq:        Interrupt to set affinity
 247  * @mask:       cpumask
 248  *
 249  * Fails if cpumask does not contain an online CPU
 250  */
 251 static inline int
 252 irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
 253 {
 254         return __irq_set_affinity(irq, cpumask, false);
 255 }
 256
 257 /**
 258  * irq_force_affinity - Force the irq affinity of a given irq
 259  * @irq:        Interrupt to set affinity
 260  * @mask:       cpumask
 261  *
 262  * Same as irq_set_affinity, but without checking the mask against
 263  * online cpus.
 264  *
 265  * Solely for low level cpu hotplug code, where we need to make per
 266  * cpu interrupts affine before the cpu becomes online.
 267  */
 268 static inline int
 269 irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
 270 {
 271         return __irq_set_affinity(irq, cpumask, true);
 272 }
 273
 274 extern int irq_can_set_affinity(unsigned int irq);
 275 extern int irq_select_affinity(unsigned int irq);
 276
 277 extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
 278
 279 /**
 280  * struct irq_affinity_notify - context for notification of IRQ affinity changes
 281  * @irq:                Interrupt to which notification applies
 282  * @kref:               Reference count, for internal use
 283  * @work:               Work item, for internal use
 284  * @notify:             Function to be called on change.  This will be
 285  *                      called in process context.
 286  * @release:            Function to be called on release.  This will be
 287  *                      called in process context.  Once registered, the
 288  *                      structure must only be freed when this function is
 289  *                      called or later.
 290  */
 291 struct irq_affinity_notify {
 292         unsigned int irq;
 293         struct kref kref;
 294         struct work_struct work;
 295         void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
 296         void (*release)(struct kref *ref);
 297 };
 298
 299 extern int
 300 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
 301
 302 #else /* CONFIG_SMP */
 303
 304 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
 305 {
 306         return -EINVAL;
 307 }
 308
 309 static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
 310 {
 311         return 0;
 312 }
 313
 314 static inline int irq_can_set_affinity(unsigned int irq)
 315 {
 316         return 0;
 317 }
 318
 319 static inline int irq_select_affinity(unsigned int irq)  { return 0; }
 320
 321 static inline int irq_set_affinity_hint(unsigned int irq,
 322                                         const struct cpumask *m)
 323 {
 324         return -EINVAL;
 325 }
 326 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
 327
 328 #ifdef CONFIG_GENERIC_HARDIRQS
 329 /*
 330  * Special lockdep variants of irq disabling/enabling.
 331  * These should be used for locking constructs that
 332  * know that a particular irq context which is disabled,
 333  * and which is the only irq-context user of a lock,
 334  * that it's safe to take the lock in the irq-disabled
 335  * section without disabling hardirqs.
 336  *
 337  * On !CONFIG_LOCKDEP they are equivalent to the normal
 338  * irq disable/enable methods.
 339  */
 340 static inline void disable_irq_nosync_lockdep(unsigned int irq)
 341 {
 342         disable_irq_nosync(irq);
 343 #ifdef CONFIG_LOCKDEP
 344         local_irq_disable();
 345 #endif
 346 }
 347
 348 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
 349 {
 350         disable_irq_nosync(irq);
 351 #ifdef CONFIG_LOCKDEP
 352         local_irq_save(*flags);
 353 #endif
 354 }
 355
 356 static inline void disable_irq_lockdep(unsigned int irq)
 357 {
 358         disable_irq(irq);
 359 #ifdef CONFIG_LOCKDEP
 360         local_irq_disable();
 361 #endif
 362 }
 363
 364 static inline void enable_irq_lockdep(unsigned int irq)
 365 {
 366 #ifdef CONFIG_LOCKDEP
 367         local_irq_enable();
 368 #endif
 369         enable_irq(irq);
 370 }
 371
 372 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
 373 {
 374 #ifdef CONFIG_LOCKDEP
 375         local_irq_restore(*flags);
 376 #endif
 377         enable_irq(irq);
 378 }
 379
 380 /* IRQ wakeup (PM) control: */
 381 extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
 382
 383 static inline int enable_irq_wake(unsigned int irq)
 384 {
 385         return irq_set_irq_wake(irq, 1);
 386 }
 387
 388 static inline int disable_irq_wake(unsigned int irq)
 389 {
 390         return irq_set_irq_wake(irq, 0);
 391 }
 392
 393 #else /* !CONFIG_GENERIC_HARDIRQS */
 394 /*
 395  * NOTE: non-genirq architectures, if they want to support the lock
 396  * validator need to define the methods below in their asm/irq.h
 397  * files, under an #ifdef CONFIG_LOCKDEP section.
 398  */
 399 #ifndef CONFIG_LOCKDEP
 400 #  define disable_irq_nosync_lockdep(irq)       disable_irq_nosync(irq)
 401 #  define disable_irq_nosync_lockdep_irqsave(irq, flags) \
 402                                                 disable_irq_nosync(irq)
 403 #  define disable_irq_lockdep(irq)              disable_irq(irq)
 404 #  define enable_irq_lockdep(irq)               enable_irq(irq)
 405 #  define enable_irq_lockdep_irqrestore(irq, flags) \
 406                                                 enable_irq(irq)
 407 # endif
 408
 409 static inline int enable_irq_wake(unsigned int irq)
 410 {
 411         return 0;
 412 }
 413
 414 static inline int disable_irq_wake(unsigned int irq)
 415 {
 416         return 0;
 417 }
 418 #endif /* CONFIG_GENERIC_HARDIRQS */
 419
 420
 421 #ifdef CONFIG_IRQ_FORCED_THREADING
 422 extern bool force_irqthreads;
 423 #else
 424 #define force_irqthreads        (0)
 425 #endif
 426
 427 #ifndef __ARCH_SET_SOFTIRQ_PENDING
 428 #define set_softirq_pending(x) (local_softirq_pending() = (x))
 429 #define or_softirq_pending(x)  (local_softirq_pending() |= (x))
 430 #endif
 431
 432 /* Some architectures might implement lazy enabling/disabling of
 433  * interrupts. In some cases, such as stop_machine, we might want
 434  * to ensure that after a local_irq_disable(), interrupts have
 435  * really been disabled in hardware. Such architectures need to
 436  * implement the following hook.
 437  */
 438 #ifndef hard_irq_disable
 439 #define hard_irq_disable()      do { } while(0)
 440 #endif
 441
 442 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
 443    frequency threaded job scheduling. For almost all the purposes
 444    tasklets are more than enough. F.e. all serial device BHs et
 445    al. should be converted to tasklets, not to softirqs.
 446  */
 447
 448 enum
 449 {
 450         HI_SOFTIRQ=0,
 451         TIMER_SOFTIRQ,
 452         NET_TX_SOFTIRQ,
 453         NET_RX_SOFTIRQ,
 454         BLOCK_SOFTIRQ,
 455         BLOCK_IOPOLL_SOFTIRQ,
 456         TASKLET_SOFTIRQ,
 457         SCHED_SOFTIRQ,
 458         HRTIMER_SOFTIRQ,
 459         RCU_SOFTIRQ,    /* Preferable RCU should always be the last softirq */
 460
 461         NR_SOFTIRQS
 462 };
 463
 464 #define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
 465
 466 /* map softirq index to softirq name. update 'softirq_to_name' in
 467  * kernel/softirq.c when adding a new softirq.
 468  */
 469 extern char *softirq_to_name[NR_SOFTIRQS];
 470
 471 /* softirq mask and active fields moved to irq_cpustat_t in
 472  * asm/hardirq.h to get better cache usage.  KAO
 473  */
 474
 475 struct softirq_action
 476 {
 477         void    (*action)(struct softirq_action *);
 478 };
 479
 480 asmlinkage void do_softirq(void);
 481 asmlinkage void __do_softirq(void);
 482 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
 483 extern void softirq_init(void);
 484 extern void __raise_softirq_irqoff(unsigned int nr);
 485
 486 extern void raise_softirq_irqoff(unsigned int nr);
 487 extern void raise_softirq(unsigned int nr);
 488
 489 DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
 490
 491 static inline struct task_struct *this_cpu_ksoftirqd(void)
 492 {
 493         return this_cpu_read(ksoftirqd);
 494 }
 495
 496 /* Tasklets --- multithreaded analogue of BHs.
 497
 498    Main feature differing them of generic softirqs: tasklet
 499    is running only on one CPU simultaneously.
 500
 501    Main feature differing them of BHs: different tasklets
 502    may be run simultaneously on different CPUs.
 503
 504    Properties:
 505    * If tasklet_schedule() is called, then tasklet is guaranteed
 506      to be executed on some cpu at least once after this.
 507    * If the tasklet is already scheduled, but its execution is still not
 508      started, it will be executed only once.
 509    * If this tasklet is already running on another CPU (or schedule is called
 510      from tasklet itself), it is rescheduled for later.
 511    * Tasklet is strictly serialized wrt itself, but not
 512      wrt another tasklets. If client needs some intertask synchronization,
 513      he makes it with spinlocks.
 514  */
 515
 516 struct tasklet_struct
 517 {
 518         struct tasklet_struct *next;
 519         unsigned long state;
 520         atomic_t count;
 521         void (*func)(unsigned long);
 522         unsigned long data;
 523 };
 524
 525 #define DECLARE_TASKLET(name, func, data) \
 526 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
 527
 528 #define DECLARE_TASKLET_DISABLED(name, func, data) \
 529 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
 530
 531
 532 enum
 533 {
 534         TASKLET_STATE_SCHED,    /* Tasklet is scheduled for execution */
 535         TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
 536 };
 537
 538 #ifdef CONFIG_SMP
 539 static inline int tasklet_trylock(struct tasklet_struct *t)
 540 {
 541         return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 542 }
 543
 544 static inline void tasklet_unlock(struct tasklet_struct *t)
 545 {
 546         smp_mb__before_clear_bit();
 547         clear_bit(TASKLET_STATE_RUN, &(t)->state);
 548 }
 549
 550 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
 551 {
 552         while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
 553 }
 554 #else
 555 #define tasklet_trylock(t) 1
 556 #define tasklet_unlock_wait(t) do { } while (0)
 557 #define tasklet_unlock(t) do { } while (0)
 558 #endif
 559
 560 extern void __tasklet_schedule(struct tasklet_struct *t);
 561
 562 static inline void tasklet_schedule(struct tasklet_struct *t)
 563 {
 564         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 565                 __tasklet_schedule(t);
 566 }
 567
 568 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
 569
 570 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
 571 {
 572         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 573                 __tasklet_hi_schedule(t);
 574 }
 575
 576 extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
 577
 578 /*
 579  * This version avoids touching any other tasklets. Needed for kmemcheck
 580  * in order not to take any page faults while enqueueing this tasklet;
 581  * consider VERY carefully whether you really need this or
 582  * tasklet_hi_schedule()...
 583  */
 584 static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
 585 {
 586         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 587                 __tasklet_hi_schedule_first(t);
 588 }
 589
 590
 591 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
 592 {
 593         atomic_inc(&t->count);
 594         smp_mb__after_atomic_inc();
 595 }
 596
 597 static inline void tasklet_disable(struct tasklet_struct *t)
 598 {
 599         tasklet_disable_nosync(t);
 600         tasklet_unlock_wait(t);
 601         smp_mb();
 602 }
 603
 604 static inline void tasklet_enable(struct tasklet_struct *t)
 605 {
 606         smp_mb__before_atomic_dec();
 607         atomic_dec(&t->count);
 608 }
 609
 610 static inline void tasklet_hi_enable(struct tasklet_struct *t)
 611 {
 612         smp_mb__before_atomic_dec();
 613         atomic_dec(&t->count);
 614 }
 615
 616 extern void tasklet_kill(struct tasklet_struct *t);
 617 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
 618 extern void tasklet_init(struct tasklet_struct *t,
 619                          void (*func)(unsigned long), unsigned long data);
 620
 621 struct tasklet_hrtimer {
 622         struct hrtimer          timer;
 623         struct tasklet_struct   tasklet;
 624         enum hrtimer_restart    (*function)(struct hrtimer *);
 625 };
 626
 627 extern void
 628 tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
 629                      enum hrtimer_restart (*function)(struct hrtimer *),
 630                      clockid_t which_clock, enum hrtimer_mode mode);
 631
 632 static inline
 633 int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
 634                           const enum hrtimer_mode mode)
 635 {
 636         return hrtimer_start(&ttimer->timer, time, mode);
 637 }
 638
 639 static inline
 640 void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
 641 {
 642         hrtimer_cancel(&ttimer->timer);
 643         tasklet_kill(&ttimer->tasklet);
 644 }
 645
 646 /*
 647  * Autoprobing for irqs:
 648  *
 649  * probe_irq_on() and probe_irq_off() provide robust primitives
 650  * for accurate IRQ probing during kernel initialization.  They are
 651  * reasonably simple to use, are not "fooled" by spurious interrupts,
 652  * and, unlike other attempts at IRQ probing, they do not get hung on
 653  * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
 654  *
 655  * For reasonably foolproof probing, use them as follows:
 656  *
 657  * 1. clear and/or mask the device's internal interrupt.
 658  * 2. sti();
 659  * 3. irqs = probe_irq_on();      // "take over" all unassigned idle IRQs
 660  * 4. enable the device and cause it to trigger an interrupt.
 661  * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
 662  * 6. irq = probe_irq_off(irqs);  // get IRQ number, 0=none, negative=multiple
 663  * 7. service the device to clear its pending interrupt.
 664  * 8. loop again if paranoia is required.
 665  *
 666  * probe_irq_on() returns a mask of allocated irq's.
 667  *
 668  * probe_irq_off() takes the mask as a parameter,
 669  * and returns the irq number which occurred,
 670  * or zero if none occurred, or a negative irq number
 671  * if more than one irq occurred.
 672  */
 673
 674 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
 675 static inline unsigned long probe_irq_on(void)
 676 {
 677         return 0;
 678 }
 679 static inline int probe_irq_off(unsigned long val)
 680 {
 681         return 0;
 682 }
 683 static inline unsigned int probe_irq_mask(unsigned long val)
 684 {
 685         return 0;
 686 }
 687 #else
 688 extern unsigned long probe_irq_on(void);        /* returns 0 on failure */
 689 extern int probe_irq_off(unsigned long);        /* returns 0 or negative on failure */
 690 extern unsigned int probe_irq_mask(unsigned long);      /* returns mask of ISA interrupts */
 691 #endif
 692
 693 #ifdef CONFIG_PROC_FS
 694 /* Initialize /proc/irq/ */
 695 extern void init_irq_proc(void);
 696 #else
 697 static inline void init_irq_proc(void)
 698 {
 699 }
 700 #endif
 701
 702 struct seq_file;
 703 int show_interrupts(struct seq_file *p, void *v);
 704 int arch_show_interrupts(struct seq_file *p, int prec);
 705
 706 extern int early_irq_init(void);
 707 extern int arch_probe_nr_irqs(void);
 708 extern int arch_early_irq_init(void);
 709
 710 #endif