2 * linux/kernel/irq/manage.c
4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5 * Copyright (C) 2005-2006 Thomas Gleixner
7 * This file contains driver APIs to the irq subsystem.
10 #define pr_fmt(fmt) "genirq: " fmt
12 #include <linux/irq.h>
13 #include <linux/kthread.h>
14 #include <linux/module.h>
15 #include <linux/random.h>
16 #include <linux/interrupt.h>
17 #include <linux/slab.h>
18 #include <linux/sched.h>
19 #include <linux/sched/rt.h>
20 #include <linux/task_work.h>
22 #include "internals.h"
24 #ifdef CONFIG_IRQ_FORCED_THREADING
25 __read_mostly bool force_irqthreads;
27 static int __init setup_forced_irqthreads(char *arg)
29 force_irqthreads = true;
32 early_param("threadirqs", setup_forced_irqthreads);
35 static void __synchronize_hardirq(struct irq_desc *desc)
43 * Wait until we're out of the critical section. This might
44 * give the wrong answer due to the lack of memory barriers.
46 while (irqd_irq_inprogress(&desc->irq_data))
49 /* Ok, that indicated we're done: double-check carefully. */
50 raw_spin_lock_irqsave(&desc->lock, flags);
51 inprogress = irqd_irq_inprogress(&desc->irq_data);
52 raw_spin_unlock_irqrestore(&desc->lock, flags);
54 /* Oops, that failed? */
59 * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
60 * @irq: interrupt number to wait for
62 * This function waits for any pending hard IRQ handlers for this
63 * interrupt to complete before returning. If you use this
64 * function while holding a resource the IRQ handler may need you
65 * will deadlock. It does not take associated threaded handlers
68 * Do not use this for shutdown scenarios where you must be sure
69 * that all parts (hardirq and threaded handler) have completed.
71 * Returns: false if a threaded handler is active.
73 * This function may be called - with care - from IRQ context.
75 bool synchronize_hardirq(unsigned int irq)
77 struct irq_desc *desc = irq_to_desc(irq);
80 __synchronize_hardirq(desc);
81 return !atomic_read(&desc->threads_active);
86 EXPORT_SYMBOL(synchronize_hardirq);
89 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
90 * @irq: interrupt number to wait for
92 * This function waits for any pending IRQ handlers for this interrupt
93 * to complete before returning. If you use this function while
94 * holding a resource the IRQ handler may need you will deadlock.
96 * This function may be called - with care - from IRQ context.
98 void synchronize_irq(unsigned int irq)
100 struct irq_desc *desc = irq_to_desc(irq);
103 __synchronize_hardirq(desc);
105 * We made sure that no hardirq handler is
106 * running. Now verify that no threaded handlers are
109 wait_event(desc->wait_for_threads,
110 !atomic_read(&desc->threads_active));
113 EXPORT_SYMBOL(synchronize_irq);
116 cpumask_var_t irq_default_affinity;
119 * irq_can_set_affinity - Check if the affinity of a given irq can be set
120 * @irq: Interrupt to check
123 int irq_can_set_affinity(unsigned int irq)
125 struct irq_desc *desc = irq_to_desc(irq);
127 if (!desc || !irqd_can_balance(&desc->irq_data) ||
128 !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
135 * irq_set_thread_affinity - Notify irq threads to adjust affinity
136 * @desc: irq descriptor which has affitnity changed
138 * We just set IRQTF_AFFINITY and delegate the affinity setting
139 * to the interrupt thread itself. We can not call
140 * set_cpus_allowed_ptr() here as we hold desc->lock and this
141 * code can be called from hard interrupt context.
143 void irq_set_thread_affinity(struct irq_desc *desc)
145 struct irqaction *action = desc->action;
149 set_bit(IRQTF_AFFINITY, &action->thread_flags);
150 action = action->next;
154 #ifdef CONFIG_GENERIC_PENDING_IRQ
155 static inline bool irq_can_move_pcntxt(struct irq_data *data)
157 return irqd_can_move_in_process_context(data);
159 static inline bool irq_move_pending(struct irq_data *data)
161 return irqd_is_setaffinity_pending(data);
164 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
166 cpumask_copy(desc->pending_mask, mask);
169 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
171 cpumask_copy(mask, desc->pending_mask);
174 static inline bool irq_can_move_pcntxt(struct irq_data *data) { return true; }
175 static inline bool irq_move_pending(struct irq_data *data) { return false; }
177 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) { }
179 irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { }
182 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
185 struct irq_desc *desc = irq_data_to_desc(data);
186 struct irq_chip *chip = irq_data_get_irq_chip(data);
189 ret = chip->irq_set_affinity(data, mask, force);
191 case IRQ_SET_MASK_OK:
192 case IRQ_SET_MASK_OK_DONE:
193 cpumask_copy(data->affinity, mask);
194 case IRQ_SET_MASK_OK_NOCOPY:
195 irq_set_thread_affinity(desc);
202 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
205 struct irq_chip *chip = irq_data_get_irq_chip(data);
206 struct irq_desc *desc = irq_data_to_desc(data);
209 if (!chip || !chip->irq_set_affinity)
212 if (irq_can_move_pcntxt(data)) {
213 ret = irq_do_set_affinity(data, mask, force);
215 irqd_set_move_pending(data);
216 irq_copy_pending(desc, mask);
219 if (desc->affinity_notify) {
220 kref_get(&desc->affinity_notify->kref);
221 schedule_work(&desc->affinity_notify->work);
223 irqd_set(data, IRQD_AFFINITY_SET);
228 int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
230 struct irq_desc *desc = irq_to_desc(irq);
237 raw_spin_lock_irqsave(&desc->lock, flags);
238 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
239 raw_spin_unlock_irqrestore(&desc->lock, flags);
243 int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
246 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
250 desc->affinity_hint = m;
251 irq_put_desc_unlock(desc, flags);
252 /* set the initial affinity to prevent every interrupt being on CPU0 */
254 __irq_set_affinity(irq, m, false);
257 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
259 static void irq_affinity_notify(struct work_struct *work)
261 struct irq_affinity_notify *notify =
262 container_of(work, struct irq_affinity_notify, work);
263 struct irq_desc *desc = irq_to_desc(notify->irq);
264 cpumask_var_t cpumask;
267 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
270 raw_spin_lock_irqsave(&desc->lock, flags);
271 if (irq_move_pending(&desc->irq_data))
272 irq_get_pending(cpumask, desc);
274 cpumask_copy(cpumask, desc->irq_data.affinity);
275 raw_spin_unlock_irqrestore(&desc->lock, flags);
277 notify->notify(notify, cpumask);
279 free_cpumask_var(cpumask);
281 kref_put(¬ify->kref, notify->release);
285 * irq_set_affinity_notifier - control notification of IRQ affinity changes
286 * @irq: Interrupt for which to enable/disable notification
287 * @notify: Context for notification, or %NULL to disable
288 * notification. Function pointers must be initialised;
289 * the other fields will be initialised by this function.
291 * Must be called in process context. Notification may only be enabled
292 * after the IRQ is allocated and must be disabled before the IRQ is
293 * freed using free_irq().
296 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
298 struct irq_desc *desc = irq_to_desc(irq);
299 struct irq_affinity_notify *old_notify;
302 /* The release function is promised process context */
308 /* Complete initialisation of *notify */
311 kref_init(¬ify->kref);
312 INIT_WORK(¬ify->work, irq_affinity_notify);
315 raw_spin_lock_irqsave(&desc->lock, flags);
316 old_notify = desc->affinity_notify;
317 desc->affinity_notify = notify;
318 raw_spin_unlock_irqrestore(&desc->lock, flags);
321 kref_put(&old_notify->kref, old_notify->release);
325 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
327 #ifndef CONFIG_AUTO_IRQ_AFFINITY
329 * Generic version of the affinity autoselector.
332 setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
334 struct cpumask *set = irq_default_affinity;
335 int node = desc->irq_data.node;
337 /* Excludes PER_CPU and NO_BALANCE interrupts */
338 if (!irq_can_set_affinity(irq))
342 * Preserve an userspace affinity setup, but make sure that
343 * one of the targets is online.
345 if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
346 if (cpumask_intersects(desc->irq_data.affinity,
348 set = desc->irq_data.affinity;
350 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
353 cpumask_and(mask, cpu_online_mask, set);
354 if (node != NUMA_NO_NODE) {
355 const struct cpumask *nodemask = cpumask_of_node(node);
357 /* make sure at least one of the cpus in nodemask is online */
358 if (cpumask_intersects(mask, nodemask))
359 cpumask_and(mask, mask, nodemask);
361 irq_do_set_affinity(&desc->irq_data, mask, false);
366 setup_affinity(unsigned int irq, struct irq_desc *d, struct cpumask *mask)
368 return irq_select_affinity(irq);
373 * Called when affinity is set via /proc/irq
375 int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask)
377 struct irq_desc *desc = irq_to_desc(irq);
381 raw_spin_lock_irqsave(&desc->lock, flags);
382 ret = setup_affinity(irq, desc, mask);
383 raw_spin_unlock_irqrestore(&desc->lock, flags);
389 setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
395 void __disable_irq(struct irq_desc *desc, unsigned int irq)
401 static int __disable_irq_nosync(unsigned int irq)
404 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
408 __disable_irq(desc, irq);
409 irq_put_desc_busunlock(desc, flags);
414 * disable_irq_nosync - disable an irq without waiting
415 * @irq: Interrupt to disable
417 * Disable the selected interrupt line. Disables and Enables are
419 * Unlike disable_irq(), this function does not ensure existing
420 * instances of the IRQ handler have completed before returning.
422 * This function may be called from IRQ context.
424 void disable_irq_nosync(unsigned int irq)
426 __disable_irq_nosync(irq);
428 EXPORT_SYMBOL(disable_irq_nosync);
431 * disable_irq - disable an irq and wait for completion
432 * @irq: Interrupt to disable
434 * Disable the selected interrupt line. Enables and Disables are
436 * This function waits for any pending IRQ handlers for this interrupt
437 * to complete before returning. If you use this function while
438 * holding a resource the IRQ handler may need you will deadlock.
440 * This function may be called - with care - from IRQ context.
442 void disable_irq(unsigned int irq)
444 if (!__disable_irq_nosync(irq))
445 synchronize_irq(irq);
447 EXPORT_SYMBOL(disable_irq);
450 * disable_hardirq - disables an irq and waits for hardirq completion
451 * @irq: Interrupt to disable
453 * Disable the selected interrupt line. Enables and Disables are
455 * This function waits for any pending hard IRQ handlers for this
456 * interrupt to complete before returning. If you use this function while
457 * holding a resource the hard IRQ handler may need you will deadlock.
459 * When used to optimistically disable an interrupt from atomic context
460 * the return value must be checked.
462 * Returns: false if a threaded handler is active.
464 * This function may be called - with care - from IRQ context.
466 bool disable_hardirq(unsigned int irq)
468 if (!__disable_irq_nosync(irq))
469 return synchronize_hardirq(irq);
473 EXPORT_SYMBOL_GPL(disable_hardirq);
475 void __enable_irq(struct irq_desc *desc, unsigned int irq)
477 switch (desc->depth) {
480 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
483 if (desc->istate & IRQS_SUSPENDED)
485 /* Prevent probing on this irq: */
486 irq_settings_set_noprobe(desc);
488 check_irq_resend(desc, irq);
497 * enable_irq - enable handling of an irq
498 * @irq: Interrupt to enable
500 * Undoes the effect of one call to disable_irq(). If this
501 * matches the last disable, processing of interrupts on this
502 * IRQ line is re-enabled.
504 * This function may be called from IRQ context only when
505 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
507 void enable_irq(unsigned int irq)
510 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
514 if (WARN(!desc->irq_data.chip,
515 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
518 __enable_irq(desc, irq);
520 irq_put_desc_busunlock(desc, flags);
522 EXPORT_SYMBOL(enable_irq);
524 static int set_irq_wake_real(unsigned int irq, unsigned int on)
526 struct irq_desc *desc = irq_to_desc(irq);
529 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
532 if (desc->irq_data.chip->irq_set_wake)
533 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
539 * irq_set_irq_wake - control irq power management wakeup
540 * @irq: interrupt to control
541 * @on: enable/disable power management wakeup
543 * Enable/disable power management wakeup mode, which is
544 * disabled by default. Enables and disables must match,
545 * just as they match for non-wakeup mode support.
547 * Wakeup mode lets this IRQ wake the system from sleep
548 * states like "suspend to RAM".
550 int irq_set_irq_wake(unsigned int irq, unsigned int on)
553 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
559 /* wakeup-capable irqs can be shared between drivers that
560 * don't need to have the same sleep mode behaviors.
563 if (desc->wake_depth++ == 0) {
564 ret = set_irq_wake_real(irq, on);
566 desc->wake_depth = 0;
568 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
571 if (desc->wake_depth == 0) {
572 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
573 } else if (--desc->wake_depth == 0) {
574 ret = set_irq_wake_real(irq, on);
576 desc->wake_depth = 1;
578 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
581 irq_put_desc_busunlock(desc, flags);
584 EXPORT_SYMBOL(irq_set_irq_wake);
587 * Internal function that tells the architecture code whether a
588 * particular irq has been exclusively allocated or is available
591 int can_request_irq(unsigned int irq, unsigned long irqflags)
594 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
600 if (irq_settings_can_request(desc)) {
602 irqflags & desc->action->flags & IRQF_SHARED)
605 irq_put_desc_unlock(desc, flags);
609 int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
612 struct irq_chip *chip = desc->irq_data.chip;
615 if (!chip || !chip->irq_set_type) {
617 * IRQF_TRIGGER_* but the PIC does not support multiple
620 pr_debug("No set_type function for IRQ %d (%s)\n", irq,
621 chip ? (chip->name ? : "unknown") : "unknown");
625 flags &= IRQ_TYPE_SENSE_MASK;
627 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
628 if (!irqd_irq_masked(&desc->irq_data))
630 if (!irqd_irq_disabled(&desc->irq_data))
634 /* caller masked out all except trigger mode flags */
635 ret = chip->irq_set_type(&desc->irq_data, flags);
638 case IRQ_SET_MASK_OK:
639 case IRQ_SET_MASK_OK_DONE:
640 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
641 irqd_set(&desc->irq_data, flags);
643 case IRQ_SET_MASK_OK_NOCOPY:
644 flags = irqd_get_trigger_type(&desc->irq_data);
645 irq_settings_set_trigger_mask(desc, flags);
646 irqd_clear(&desc->irq_data, IRQD_LEVEL);
647 irq_settings_clr_level(desc);
648 if (flags & IRQ_TYPE_LEVEL_MASK) {
649 irq_settings_set_level(desc);
650 irqd_set(&desc->irq_data, IRQD_LEVEL);
656 pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
657 flags, irq, chip->irq_set_type);
664 #ifdef CONFIG_HARDIRQS_SW_RESEND
665 int irq_set_parent(int irq, int parent_irq)
668 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
673 desc->parent_irq = parent_irq;
675 irq_put_desc_unlock(desc, flags);
681 * Default primary interrupt handler for threaded interrupts. Is
682 * assigned as primary handler when request_threaded_irq is called
683 * with handler == NULL. Useful for oneshot interrupts.
685 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
687 return IRQ_WAKE_THREAD;
691 * Primary handler for nested threaded interrupts. Should never be
694 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
696 WARN(1, "Primary handler called for nested irq %d\n", irq);
700 static int irq_wait_for_interrupt(struct irqaction *action)
702 set_current_state(TASK_INTERRUPTIBLE);
704 while (!kthread_should_stop()) {
706 if (test_and_clear_bit(IRQTF_RUNTHREAD,
707 &action->thread_flags)) {
708 __set_current_state(TASK_RUNNING);
712 set_current_state(TASK_INTERRUPTIBLE);
714 __set_current_state(TASK_RUNNING);
719 * Oneshot interrupts keep the irq line masked until the threaded
720 * handler finished. unmask if the interrupt has not been disabled and
723 static void irq_finalize_oneshot(struct irq_desc *desc,
724 struct irqaction *action)
726 if (!(desc->istate & IRQS_ONESHOT))
730 raw_spin_lock_irq(&desc->lock);
733 * Implausible though it may be we need to protect us against
734 * the following scenario:
736 * The thread is faster done than the hard interrupt handler
737 * on the other CPU. If we unmask the irq line then the
738 * interrupt can come in again and masks the line, leaves due
739 * to IRQS_INPROGRESS and the irq line is masked forever.
741 * This also serializes the state of shared oneshot handlers
742 * versus "desc->threads_onehsot |= action->thread_mask;" in
743 * irq_wake_thread(). See the comment there which explains the
746 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
747 raw_spin_unlock_irq(&desc->lock);
748 chip_bus_sync_unlock(desc);
754 * Now check again, whether the thread should run. Otherwise
755 * we would clear the threads_oneshot bit of this thread which
758 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
761 desc->threads_oneshot &= ~action->thread_mask;
763 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
764 irqd_irq_masked(&desc->irq_data))
765 unmask_threaded_irq(desc);
768 raw_spin_unlock_irq(&desc->lock);
769 chip_bus_sync_unlock(desc);
774 * Check whether we need to change the affinity of the interrupt thread.
777 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
782 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
786 * In case we are out of memory we set IRQTF_AFFINITY again and
787 * try again next time
789 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
790 set_bit(IRQTF_AFFINITY, &action->thread_flags);
794 raw_spin_lock_irq(&desc->lock);
796 * This code is triggered unconditionally. Check the affinity
797 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
799 if (desc->irq_data.affinity)
800 cpumask_copy(mask, desc->irq_data.affinity);
803 raw_spin_unlock_irq(&desc->lock);
806 set_cpus_allowed_ptr(current, mask);
807 free_cpumask_var(mask);
811 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
815 * Interrupts which are not explicitely requested as threaded
816 * interrupts rely on the implicit bh/preempt disable of the hard irq
817 * context. So we need to disable bh here to avoid deadlocks and other
821 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
826 ret = action->thread_fn(action->irq, action->dev_id);
827 irq_finalize_oneshot(desc, action);
833 * Interrupts explicitly requested as threaded interrupts want to be
834 * preemtible - many of them need to sleep and wait for slow busses to
837 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
838 struct irqaction *action)
842 ret = action->thread_fn(action->irq, action->dev_id);
843 irq_finalize_oneshot(desc, action);
847 static void wake_threads_waitq(struct irq_desc *desc)
849 if (atomic_dec_and_test(&desc->threads_active))
850 wake_up(&desc->wait_for_threads);
853 static void irq_thread_dtor(struct callback_head *unused)
855 struct task_struct *tsk = current;
856 struct irq_desc *desc;
857 struct irqaction *action;
859 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
862 action = kthread_data(tsk);
864 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
865 tsk->comm, tsk->pid, action->irq);
868 desc = irq_to_desc(action->irq);
870 * If IRQTF_RUNTHREAD is set, we need to decrement
871 * desc->threads_active and wake possible waiters.
873 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
874 wake_threads_waitq(desc);
876 /* Prevent a stale desc->threads_oneshot */
877 irq_finalize_oneshot(desc, action);
881 * Interrupt handler thread
883 static int irq_thread(void *data)
885 struct callback_head on_exit_work;
886 struct irqaction *action = data;
887 struct irq_desc *desc = irq_to_desc(action->irq);
888 irqreturn_t (*handler_fn)(struct irq_desc *desc,
889 struct irqaction *action);
891 if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
892 &action->thread_flags))
893 handler_fn = irq_forced_thread_fn;
895 handler_fn = irq_thread_fn;
897 init_task_work(&on_exit_work, irq_thread_dtor);
898 task_work_add(current, &on_exit_work, false);
900 irq_thread_check_affinity(desc, action);
902 while (!irq_wait_for_interrupt(action)) {
903 irqreturn_t action_ret;
905 irq_thread_check_affinity(desc, action);
907 action_ret = handler_fn(desc, action);
908 if (action_ret == IRQ_HANDLED)
909 atomic_inc(&desc->threads_handled);
911 wake_threads_waitq(desc);
915 * This is the regular exit path. __free_irq() is stopping the
916 * thread via kthread_stop() after calling
917 * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
918 * oneshot mask bit can be set. We cannot verify that as we
919 * cannot touch the oneshot mask at this point anymore as
920 * __setup_irq() might have given out currents thread_mask
923 task_work_cancel(current, irq_thread_dtor);
928 * irq_wake_thread - wake the irq thread for the action identified by dev_id
929 * @irq: Interrupt line
930 * @dev_id: Device identity for which the thread should be woken
933 void irq_wake_thread(unsigned int irq, void *dev_id)
935 struct irq_desc *desc = irq_to_desc(irq);
936 struct irqaction *action;
939 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
942 raw_spin_lock_irqsave(&desc->lock, flags);
943 for (action = desc->action; action; action = action->next) {
944 if (action->dev_id == dev_id) {
946 __irq_wake_thread(desc, action);
950 raw_spin_unlock_irqrestore(&desc->lock, flags);
952 EXPORT_SYMBOL_GPL(irq_wake_thread);
954 static void irq_setup_forced_threading(struct irqaction *new)
956 if (!force_irqthreads)
958 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
961 new->flags |= IRQF_ONESHOT;
963 if (!new->thread_fn) {
964 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
965 new->thread_fn = new->handler;
966 new->handler = irq_default_primary_handler;
970 static int irq_request_resources(struct irq_desc *desc)
972 struct irq_data *d = &desc->irq_data;
973 struct irq_chip *c = d->chip;
975 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
978 static void irq_release_resources(struct irq_desc *desc)
980 struct irq_data *d = &desc->irq_data;
981 struct irq_chip *c = d->chip;
983 if (c->irq_release_resources)
984 c->irq_release_resources(d);
988 * Internal function to register an irqaction - typically used to
989 * allocate special interrupts that are part of the architecture.
992 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
994 struct irqaction *old, **old_ptr;
995 unsigned long flags, thread_mask = 0;
996 int ret, nested, shared = 0;
1002 if (desc->irq_data.chip == &no_irq_chip)
1004 if (!try_module_get(desc->owner))
1008 * Check whether the interrupt nests into another interrupt
1011 nested = irq_settings_is_nested_thread(desc);
1013 if (!new->thread_fn) {
1018 * Replace the primary handler which was provided from
1019 * the driver for non nested interrupt handling by the
1020 * dummy function which warns when called.
1022 new->handler = irq_nested_primary_handler;
1024 if (irq_settings_can_thread(desc))
1025 irq_setup_forced_threading(new);
1029 * Create a handler thread when a thread function is supplied
1030 * and the interrupt does not nest into another interrupt
1033 if (new->thread_fn && !nested) {
1034 struct task_struct *t;
1035 static const struct sched_param param = {
1036 .sched_priority = MAX_USER_RT_PRIO/2,
1039 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1046 sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m);
1049 * We keep the reference to the task struct even if
1050 * the thread dies to avoid that the interrupt code
1051 * references an already freed task_struct.
1056 * Tell the thread to set its affinity. This is
1057 * important for shared interrupt handlers as we do
1058 * not invoke setup_affinity() for the secondary
1059 * handlers as everything is already set up. Even for
1060 * interrupts marked with IRQF_NO_BALANCE this is
1061 * correct as we want the thread to move to the cpu(s)
1062 * on which the requesting code placed the interrupt.
1064 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1067 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1073 * Drivers are often written to work w/o knowledge about the
1074 * underlying irq chip implementation, so a request for a
1075 * threaded irq without a primary hard irq context handler
1076 * requires the ONESHOT flag to be set. Some irq chips like
1077 * MSI based interrupts are per se one shot safe. Check the
1078 * chip flags, so we can avoid the unmask dance at the end of
1079 * the threaded handler for those.
1081 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1082 new->flags &= ~IRQF_ONESHOT;
1085 * The following block of code has to be executed atomically
1087 raw_spin_lock_irqsave(&desc->lock, flags);
1088 old_ptr = &desc->action;
1092 * Can't share interrupts unless both agree to and are
1093 * the same type (level, edge, polarity). So both flag
1094 * fields must have IRQF_SHARED set and the bits which
1095 * set the trigger type must match. Also all must
1098 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1099 ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) ||
1100 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1103 /* All handlers must agree on per-cpuness */
1104 if ((old->flags & IRQF_PERCPU) !=
1105 (new->flags & IRQF_PERCPU))
1108 /* add new interrupt at end of irq queue */
1111 * Or all existing action->thread_mask bits,
1112 * so we can find the next zero bit for this
1115 thread_mask |= old->thread_mask;
1116 old_ptr = &old->next;
1123 * Setup the thread mask for this irqaction for ONESHOT. For
1124 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1125 * conditional in irq_wake_thread().
1127 if (new->flags & IRQF_ONESHOT) {
1129 * Unlikely to have 32 resp 64 irqs sharing one line,
1132 if (thread_mask == ~0UL) {
1137 * The thread_mask for the action is or'ed to
1138 * desc->thread_active to indicate that the
1139 * IRQF_ONESHOT thread handler has been woken, but not
1140 * yet finished. The bit is cleared when a thread
1141 * completes. When all threads of a shared interrupt
1142 * line have completed desc->threads_active becomes
1143 * zero and the interrupt line is unmasked. See
1144 * handle.c:irq_wake_thread() for further information.
1146 * If no thread is woken by primary (hard irq context)
1147 * interrupt handlers, then desc->threads_active is
1148 * also checked for zero to unmask the irq line in the
1149 * affected hard irq flow handlers
1150 * (handle_[fasteoi|level]_irq).
1152 * The new action gets the first zero bit of
1153 * thread_mask assigned. See the loop above which or's
1154 * all existing action->thread_mask bits.
1156 new->thread_mask = 1 << ffz(thread_mask);
1158 } else if (new->handler == irq_default_primary_handler &&
1159 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1161 * The interrupt was requested with handler = NULL, so
1162 * we use the default primary handler for it. But it
1163 * does not have the oneshot flag set. In combination
1164 * with level interrupts this is deadly, because the
1165 * default primary handler just wakes the thread, then
1166 * the irq lines is reenabled, but the device still
1167 * has the level irq asserted. Rinse and repeat....
1169 * While this works for edge type interrupts, we play
1170 * it safe and reject unconditionally because we can't
1171 * say for sure which type this interrupt really
1172 * has. The type flags are unreliable as the
1173 * underlying chip implementation can override them.
1175 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
1182 ret = irq_request_resources(desc);
1184 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1185 new->name, irq, desc->irq_data.chip->name);
1189 init_waitqueue_head(&desc->wait_for_threads);
1191 /* Setup the type (level, edge polarity) if configured: */
1192 if (new->flags & IRQF_TRIGGER_MASK) {
1193 ret = __irq_set_trigger(desc, irq,
1194 new->flags & IRQF_TRIGGER_MASK);
1200 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1201 IRQS_ONESHOT | IRQS_WAITING);
1202 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1204 if (new->flags & IRQF_PERCPU) {
1205 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1206 irq_settings_set_per_cpu(desc);
1209 if (new->flags & IRQF_ONESHOT)
1210 desc->istate |= IRQS_ONESHOT;
1212 if (irq_settings_can_autoenable(desc))
1213 irq_startup(desc, true);
1215 /* Undo nested disables: */
1218 /* Exclude IRQ from balancing if requested */
1219 if (new->flags & IRQF_NOBALANCING) {
1220 irq_settings_set_no_balancing(desc);
1221 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1224 /* Set default affinity mask once everything is setup */
1225 setup_affinity(irq, desc, mask);
1227 } else if (new->flags & IRQF_TRIGGER_MASK) {
1228 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1229 unsigned int omsk = irq_settings_get_trigger_mask(desc);
1232 /* hope the handler works with current trigger mode */
1233 pr_warning("irq %d uses trigger mode %u; requested %u\n",
1240 irq_pm_install_action(desc, new);
1242 /* Reset broken irq detection when installing new handler */
1243 desc->irq_count = 0;
1244 desc->irqs_unhandled = 0;
1247 * Check whether we disabled the irq via the spurious handler
1248 * before. Reenable it and give it another chance.
1250 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1251 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1252 __enable_irq(desc, irq);
1255 raw_spin_unlock_irqrestore(&desc->lock, flags);
1258 * Strictly no need to wake it up, but hung_task complains
1259 * when no hard interrupt wakes the thread up.
1262 wake_up_process(new->thread);
1264 register_irq_proc(irq, desc);
1266 register_handler_proc(irq, new);
1267 free_cpumask_var(mask);
1272 if (!(new->flags & IRQF_PROBE_SHARED)) {
1273 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1274 irq, new->flags, new->name, old->flags, old->name);
1275 #ifdef CONFIG_DEBUG_SHIRQ
1282 raw_spin_unlock_irqrestore(&desc->lock, flags);
1283 free_cpumask_var(mask);
1287 struct task_struct *t = new->thread;
1294 module_put(desc->owner);
1299 * setup_irq - setup an interrupt
1300 * @irq: Interrupt line to setup
1301 * @act: irqaction for the interrupt
1303 * Used to statically setup interrupts in the early boot process.
1305 int setup_irq(unsigned int irq, struct irqaction *act)
1308 struct irq_desc *desc = irq_to_desc(irq);
1310 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1312 chip_bus_lock(desc);
1313 retval = __setup_irq(irq, desc, act);
1314 chip_bus_sync_unlock(desc);
1318 EXPORT_SYMBOL_GPL(setup_irq);
1321 * Internal function to unregister an irqaction - used to free
1322 * regular and special interrupts that are part of the architecture.
1324 static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
1326 struct irq_desc *desc = irq_to_desc(irq);
1327 struct irqaction *action, **action_ptr;
1328 unsigned long flags;
1330 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1335 raw_spin_lock_irqsave(&desc->lock, flags);
1338 * There can be multiple actions per IRQ descriptor, find the right
1339 * one based on the dev_id:
1341 action_ptr = &desc->action;
1343 action = *action_ptr;
1346 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1347 raw_spin_unlock_irqrestore(&desc->lock, flags);
1352 if (action->dev_id == dev_id)
1354 action_ptr = &action->next;
1357 /* Found it - now remove it from the list of entries: */
1358 *action_ptr = action->next;
1360 irq_pm_remove_action(desc, action);
1362 /* If this was the last handler, shut down the IRQ line: */
1363 if (!desc->action) {
1365 irq_release_resources(desc);
1369 /* make sure affinity_hint is cleaned up */
1370 if (WARN_ON_ONCE(desc->affinity_hint))
1371 desc->affinity_hint = NULL;
1374 raw_spin_unlock_irqrestore(&desc->lock, flags);
1376 unregister_handler_proc(irq, action);
1378 /* Make sure it's not being used on another CPU: */
1379 synchronize_irq(irq);
1381 #ifdef CONFIG_DEBUG_SHIRQ
1383 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1384 * event to happen even now it's being freed, so let's make sure that
1385 * is so by doing an extra call to the handler ....
1387 * ( We do this after actually deregistering it, to make sure that a
1388 * 'real' IRQ doesn't run in * parallel with our fake. )
1390 if (action->flags & IRQF_SHARED) {
1391 local_irq_save(flags);
1392 action->handler(irq, dev_id);
1393 local_irq_restore(flags);
1397 if (action->thread) {
1398 kthread_stop(action->thread);
1399 put_task_struct(action->thread);
1402 module_put(desc->owner);
1407 * remove_irq - free an interrupt
1408 * @irq: Interrupt line to free
1409 * @act: irqaction for the interrupt
1411 * Used to remove interrupts statically setup by the early boot process.
1413 void remove_irq(unsigned int irq, struct irqaction *act)
1415 struct irq_desc *desc = irq_to_desc(irq);
1417 if (desc && !WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1418 __free_irq(irq, act->dev_id);
1420 EXPORT_SYMBOL_GPL(remove_irq);
1423 * free_irq - free an interrupt allocated with request_irq
1424 * @irq: Interrupt line to free
1425 * @dev_id: Device identity to free
1427 * Remove an interrupt handler. The handler is removed and if the
1428 * interrupt line is no longer in use by any driver it is disabled.
1429 * On a shared IRQ the caller must ensure the interrupt is disabled
1430 * on the card it drives before calling this function. The function
1431 * does not return until any executing interrupts for this IRQ
1434 * This function must not be called from interrupt context.
1436 void free_irq(unsigned int irq, void *dev_id)
1438 struct irq_desc *desc = irq_to_desc(irq);
1440 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1444 if (WARN_ON(desc->affinity_notify))
1445 desc->affinity_notify = NULL;
1448 chip_bus_lock(desc);
1449 kfree(__free_irq(irq, dev_id));
1450 chip_bus_sync_unlock(desc);
1452 EXPORT_SYMBOL(free_irq);
1455 * request_threaded_irq - allocate an interrupt line
1456 * @irq: Interrupt line to allocate
1457 * @handler: Function to be called when the IRQ occurs.
1458 * Primary handler for threaded interrupts
1459 * If NULL and thread_fn != NULL the default
1460 * primary handler is installed
1461 * @thread_fn: Function called from the irq handler thread
1462 * If NULL, no irq thread is created
1463 * @irqflags: Interrupt type flags
1464 * @devname: An ascii name for the claiming device
1465 * @dev_id: A cookie passed back to the handler function
1467 * This call allocates interrupt resources and enables the
1468 * interrupt line and IRQ handling. From the point this
1469 * call is made your handler function may be invoked. Since
1470 * your handler function must clear any interrupt the board
1471 * raises, you must take care both to initialise your hardware
1472 * and to set up the interrupt handler in the right order.
1474 * If you want to set up a threaded irq handler for your device
1475 * then you need to supply @handler and @thread_fn. @handler is
1476 * still called in hard interrupt context and has to check
1477 * whether the interrupt originates from the device. If yes it
1478 * needs to disable the interrupt on the device and return
1479 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1480 * @thread_fn. This split handler design is necessary to support
1481 * shared interrupts.
1483 * Dev_id must be globally unique. Normally the address of the
1484 * device data structure is used as the cookie. Since the handler
1485 * receives this value it makes sense to use it.
1487 * If your interrupt is shared you must pass a non NULL dev_id
1488 * as this is required when freeing the interrupt.
1492 * IRQF_SHARED Interrupt is shared
1493 * IRQF_TRIGGER_* Specify active edge(s) or level
1496 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
1497 irq_handler_t thread_fn, unsigned long irqflags,
1498 const char *devname, void *dev_id)
1500 struct irqaction *action;
1501 struct irq_desc *desc;
1505 * Sanity-check: shared interrupts must pass in a real dev-ID,
1506 * otherwise we'll have trouble later trying to figure out
1507 * which interrupt is which (messes up the interrupt freeing
1510 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1511 * it cannot be set along with IRQF_NO_SUSPEND.
1513 if (((irqflags & IRQF_SHARED) && !dev_id) ||
1514 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
1515 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
1518 desc = irq_to_desc(irq);
1522 if (!irq_settings_can_request(desc) ||
1523 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1529 handler = irq_default_primary_handler;
1532 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1536 action->handler = handler;
1537 action->thread_fn = thread_fn;
1538 action->flags = irqflags;
1539 action->name = devname;
1540 action->dev_id = dev_id;
1542 chip_bus_lock(desc);
1543 retval = __setup_irq(irq, desc, action);
1544 chip_bus_sync_unlock(desc);
1549 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1550 if (!retval && (irqflags & IRQF_SHARED)) {
1552 * It's a shared IRQ -- the driver ought to be prepared for it
1553 * to happen immediately, so let's make sure....
1554 * We disable the irq to make sure that a 'real' IRQ doesn't
1555 * run in parallel with our fake.
1557 unsigned long flags;
1560 local_irq_save(flags);
1562 handler(irq, dev_id);
1564 local_irq_restore(flags);
1570 EXPORT_SYMBOL(request_threaded_irq);
1573 * request_any_context_irq - allocate an interrupt line
1574 * @irq: Interrupt line to allocate
1575 * @handler: Function to be called when the IRQ occurs.
1576 * Threaded handler for threaded interrupts.
1577 * @flags: Interrupt type flags
1578 * @name: An ascii name for the claiming device
1579 * @dev_id: A cookie passed back to the handler function
1581 * This call allocates interrupt resources and enables the
1582 * interrupt line and IRQ handling. It selects either a
1583 * hardirq or threaded handling method depending on the
1586 * On failure, it returns a negative value. On success,
1587 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1589 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
1590 unsigned long flags, const char *name, void *dev_id)
1592 struct irq_desc *desc = irq_to_desc(irq);
1598 if (irq_settings_is_nested_thread(desc)) {
1599 ret = request_threaded_irq(irq, NULL, handler,
1600 flags, name, dev_id);
1601 return !ret ? IRQC_IS_NESTED : ret;
1604 ret = request_irq(irq, handler, flags, name, dev_id);
1605 return !ret ? IRQC_IS_HARDIRQ : ret;
1607 EXPORT_SYMBOL_GPL(request_any_context_irq);
1609 void enable_percpu_irq(unsigned int irq, unsigned int type)
1611 unsigned int cpu = smp_processor_id();
1612 unsigned long flags;
1613 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
1618 type &= IRQ_TYPE_SENSE_MASK;
1619 if (type != IRQ_TYPE_NONE) {
1622 ret = __irq_set_trigger(desc, irq, type);
1625 WARN(1, "failed to set type for IRQ%d\n", irq);
1630 irq_percpu_enable(desc, cpu);
1632 irq_put_desc_unlock(desc, flags);
1634 EXPORT_SYMBOL_GPL(enable_percpu_irq);
1636 void disable_percpu_irq(unsigned int irq)
1638 unsigned int cpu = smp_processor_id();
1639 unsigned long flags;
1640 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
1645 irq_percpu_disable(desc, cpu);
1646 irq_put_desc_unlock(desc, flags);
1648 EXPORT_SYMBOL_GPL(disable_percpu_irq);
1651 * Internal function to unregister a percpu irqaction.
1653 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
1655 struct irq_desc *desc = irq_to_desc(irq);
1656 struct irqaction *action;
1657 unsigned long flags;
1659 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1664 raw_spin_lock_irqsave(&desc->lock, flags);
1666 action = desc->action;
1667 if (!action || action->percpu_dev_id != dev_id) {
1668 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1672 if (!cpumask_empty(desc->percpu_enabled)) {
1673 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1674 irq, cpumask_first(desc->percpu_enabled));
1678 /* Found it - now remove it from the list of entries: */
1679 desc->action = NULL;
1681 raw_spin_unlock_irqrestore(&desc->lock, flags);
1683 unregister_handler_proc(irq, action);
1685 module_put(desc->owner);
1689 raw_spin_unlock_irqrestore(&desc->lock, flags);
1694 * remove_percpu_irq - free a per-cpu interrupt
1695 * @irq: Interrupt line to free
1696 * @act: irqaction for the interrupt
1698 * Used to remove interrupts statically setup by the early boot process.
1700 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
1702 struct irq_desc *desc = irq_to_desc(irq);
1704 if (desc && irq_settings_is_per_cpu_devid(desc))
1705 __free_percpu_irq(irq, act->percpu_dev_id);
1709 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1710 * @irq: Interrupt line to free
1711 * @dev_id: Device identity to free
1713 * Remove a percpu interrupt handler. The handler is removed, but
1714 * the interrupt line is not disabled. This must be done on each
1715 * CPU before calling this function. The function does not return
1716 * until any executing interrupts for this IRQ have completed.
1718 * This function must not be called from interrupt context.
1720 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
1722 struct irq_desc *desc = irq_to_desc(irq);
1724 if (!desc || !irq_settings_is_per_cpu_devid(desc))
1727 chip_bus_lock(desc);
1728 kfree(__free_percpu_irq(irq, dev_id));
1729 chip_bus_sync_unlock(desc);
1733 * setup_percpu_irq - setup a per-cpu interrupt
1734 * @irq: Interrupt line to setup
1735 * @act: irqaction for the interrupt
1737 * Used to statically setup per-cpu interrupts in the early boot process.
1739 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
1741 struct irq_desc *desc = irq_to_desc(irq);
1744 if (!desc || !irq_settings_is_per_cpu_devid(desc))
1746 chip_bus_lock(desc);
1747 retval = __setup_irq(irq, desc, act);
1748 chip_bus_sync_unlock(desc);
1754 * request_percpu_irq - allocate a percpu interrupt line
1755 * @irq: Interrupt line to allocate
1756 * @handler: Function to be called when the IRQ occurs.
1757 * @devname: An ascii name for the claiming device
1758 * @dev_id: A percpu cookie passed back to the handler function
1760 * This call allocates interrupt resources, but doesn't
1761 * automatically enable the interrupt. It has to be done on each
1762 * CPU using enable_percpu_irq().
1764 * Dev_id must be globally unique. It is a per-cpu variable, and
1765 * the handler gets called with the interrupted CPU's instance of
1768 int request_percpu_irq(unsigned int irq, irq_handler_t handler,
1769 const char *devname, void __percpu *dev_id)
1771 struct irqaction *action;
1772 struct irq_desc *desc;
1778 desc = irq_to_desc(irq);
1779 if (!desc || !irq_settings_can_request(desc) ||
1780 !irq_settings_is_per_cpu_devid(desc))
1783 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1787 action->handler = handler;
1788 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND;
1789 action->name = devname;
1790 action->percpu_dev_id = dev_id;
1792 chip_bus_lock(desc);
1793 retval = __setup_irq(irq, desc, action);
1794 chip_bus_sync_unlock(desc);
1803 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
1804 * @irq: Interrupt line that is forwarded to a VM
1805 * @which: One of IRQCHIP_STATE_* the caller wants to know about
1806 * @state: a pointer to a boolean where the state is to be storeed
1808 * This call snapshots the internal irqchip state of an
1809 * interrupt, returning into @state the bit corresponding to
1812 * This function should be called with preemption disabled if the
1813 * interrupt controller has per-cpu registers.
1815 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
1818 struct irq_desc *desc;
1819 struct irq_data *data;
1820 struct irq_chip *chip;
1821 unsigned long flags;
1824 desc = irq_get_desc_buslock(irq, &flags, 0);
1828 data = irq_desc_get_irq_data(desc);
1831 chip = irq_data_get_irq_chip(data);
1832 if (chip->irq_get_irqchip_state)
1834 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1835 data = data->parent_data;
1842 err = chip->irq_get_irqchip_state(data, which, state);
1844 irq_put_desc_busunlock(desc, flags);
1849 * irq_set_irqchip_state - set the state of a forwarded interrupt.
1850 * @irq: Interrupt line that is forwarded to a VM
1851 * @which: State to be restored (one of IRQCHIP_STATE_*)
1852 * @val: Value corresponding to @which
1854 * This call sets the internal irqchip state of an interrupt,
1855 * depending on the value of @which.
1857 * This function should be called with preemption disabled if the
1858 * interrupt controller has per-cpu registers.
1860 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
1863 struct irq_desc *desc;
1864 struct irq_data *data;
1865 struct irq_chip *chip;
1866 unsigned long flags;
1869 desc = irq_get_desc_buslock(irq, &flags, 0);
1873 data = irq_desc_get_irq_data(desc);
1876 chip = irq_data_get_irq_chip(data);
1877 if (chip->irq_set_irqchip_state)
1879 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1880 data = data->parent_data;
1887 err = chip->irq_set_irqchip_state(data, which, val);
1889 irq_put_desc_busunlock(desc, flags);