6  * This file contains driver APIs to the irq subsystem.
11 #include <linux/irq.h>
77  *	synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
78  *	@irq: interrupt number to wait for
80  *	This function waits for any pending hard IRQ handlers for this
82  *	function while holding a resource the IRQ handler may need you
91  *	This function may be called - with care - from IRQ context.
98 bool synchronize_hardirq(unsigned int irq)  in synchronize_hardirq()  argument
100 	struct irq_desc *desc = irq_to_desc(irq);  in synchronize_hardirq()
112  *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
113  *	@irq: interrupt number to wait for
115  *	This function waits for any pending IRQ handlers for this interrupt
117  *	holding a resource the IRQ handler may need you will deadlock.
120  *	an interrupt thread is associated to @irq.
122  *	It optionally makes sure (when the irq chip supports that method)
126 void synchronize_irq(unsigned int irq)  in synchronize_irq()  argument
128 	struct irq_desc *desc = irq_to_desc(irq);  in synchronize_irq()
155  *	irq_can_set_affinity - Check if the affinity of a given irq can be set
156  *	@irq:		Interrupt to check
159 int irq_can_set_affinity(unsigned int irq)  in irq_can_set_affinity()  argument
161 	return __irq_can_set_affinity(irq_to_desc(irq));  in irq_can_set_affinity()
165  * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
166  * @irq:	Interrupt to check
171 bool irq_can_set_affinity_usr(unsigned int irq)  in irq_can_set_affinity_usr()  argument
173 	struct irq_desc *desc = irq_to_desc(irq);  in irq_can_set_affinity_usr()
180  *	irq_set_thread_affinity - Notify irq threads to adjust affinity
181  *	@desc:		irq descriptor which has affinity changed
205 	pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",  in irq_validate_effective_affinity()
206 		     chip->name, data->irq);  in irq_validate_effective_affinity()
329 	 * Handle irq chips which can handle affinity only in activated  in irq_set_affinity_deactivated()
382  * @irq:	The interrupt number to update
389  * for when the kernel is configured for generic IRQ reservation mode (in
395 int irq_update_affinity_desc(unsigned int irq,  in irq_update_affinity_desc()  argument
410 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_update_affinity_desc()
450 static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,  in __irq_set_affinity()  argument
453 	struct irq_desc *desc = irq_to_desc(irq);  in __irq_set_affinity()
467  * irq_set_affinity - Set the irq affinity of a given irq
468  * @irq:	Interrupt to set affinity
473 int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)  in irq_set_affinity()  argument
475 	return __irq_set_affinity(irq, cpumask, false);  in irq_set_affinity()
480  * irq_force_affinity - Force the irq affinity of a given irq
481  * @irq:	Interrupt to set affinity
490 int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)  in irq_force_affinity()  argument
492 	return __irq_set_affinity(irq, cpumask, true);  in irq_force_affinity()
496 int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,  in __irq_apply_affinity_hint()  argument
500 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in __irq_apply_affinity_hint()
507 		__irq_set_affinity(irq, m, false);  in __irq_apply_affinity_hint()
516 	struct irq_desc *desc = irq_to_desc(notify->irq);  in irq_affinity_notify()
538  *	irq_set_affinity_notifier - control notification of IRQ affinity changes
539  *	@irq:		Interrupt for which to enable/disable notification
545  *	after the IRQ is allocated and must be disabled before the IRQ is
549 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)  in irq_set_affinity_notifier()  argument
551 	struct irq_desc *desc = irq_to_desc(irq);  in irq_set_affinity_notifier()
563 		notify->irq = irq;  in irq_set_affinity_notifier()
641  *	@irq: interrupt number to set affinity
646  *	affinity for an irq. The vCPU specific data is passed from
650 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)  in irq_set_vcpu_affinity()  argument
653 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in irq_set_vcpu_affinity()
687 static int __disable_irq_nosync(unsigned int irq)  in __disable_irq_nosync()  argument
690 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in __disable_irq_nosync()
700  *	disable_irq_nosync - disable an irq without waiting
701  *	@irq: Interrupt to disable
706  *	instances of the IRQ handler have completed before returning.
708  *	This function may be called from IRQ context.
710 void disable_irq_nosync(unsigned int irq)  in disable_irq_nosync()  argument
712 	__disable_irq_nosync(irq);  in disable_irq_nosync()
717  *	disable_irq - disable an irq and wait for completion
718  *	@irq: Interrupt to disable
722  *	This function waits for any pending IRQ handlers for this interrupt
724  *	holding a resource the IRQ handler may need you will deadlock.
726  *	This function may be called - with care - from IRQ context.
728 void disable_irq(unsigned int irq)  in disable_irq()  argument
730 	if (!__disable_irq_nosync(irq))  in disable_irq()
731 		synchronize_irq(irq);  in disable_irq()
736  *	disable_hardirq - disables an irq and waits for hardirq completion
737  *	@irq: Interrupt to disable
741  *	This function waits for any pending hard IRQ handlers for this
743  *	holding a resource the hard IRQ handler may need you will deadlock.
750  *	This function may be called - with care - from IRQ context.
752 bool disable_hardirq(unsigned int irq)  in disable_hardirq()  argument
754 	if (!__disable_irq_nosync(irq))  in disable_hardirq()
755 		return synchronize_hardirq(irq);  in disable_hardirq()
763  *	@irq: Interrupt to disable
769  *	instances of the IRQ handler have completed before returning.
771 void disable_nmi_nosync(unsigned int irq)  in disable_nmi_nosync()  argument
773 	disable_irq_nosync(irq);  in disable_nmi_nosync()
781 		WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",  in __enable_irq()
787 		/* Prevent probing on this irq: */  in __enable_irq()
805  *	enable_irq - enable handling of an irq
806  *	@irq: Interrupt to enable
810  *	IRQ line is re-enabled.
812  *	This function may be called from IRQ context only when
815 void enable_irq(unsigned int irq)  in enable_irq()  argument
818 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in enable_irq()
823 		 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))  in enable_irq()
834  *	@irq: Interrupt to enable
839  *	IRQ line is re-enabled.
841 void enable_nmi(unsigned int irq)  in enable_nmi()  argument
843 	enable_irq(irq);  in enable_nmi()
846 static int set_irq_wake_real(unsigned int irq, unsigned int on)  in set_irq_wake_real()  argument
848 	struct irq_desc *desc = irq_to_desc(irq);  in set_irq_wake_real()
861  *	irq_set_irq_wake - control irq power management wakeup
862  *	@irq:	interrupt to control
869  *	Wakeup mode lets this IRQ wake the system from sleep
872  *	Note: irq enable/disable state is completely orthogonal
873  *	to the enable/disable state of irq wake. An irq can be
875  *	long as the irq has wake enabled. If this does not hold,
876  *	then the underlying irq chip and the related driver need
879 int irq_set_irq_wake(unsigned int irq, unsigned int on)  in irq_set_irq_wake()  argument
882 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in irq_set_irq_wake()
899 			ret = set_irq_wake_real(irq, on);  in irq_set_irq_wake()
907 			WARN(1, "Unbalanced IRQ %d wake disable\n", irq);  in irq_set_irq_wake()
909 			ret = set_irq_wake_real(irq, on);  in irq_set_irq_wake()
925  * particular irq has been exclusively allocated or is available
928 int can_request_irq(unsigned int irq, unsigned long irqflags)  in can_request_irq()  argument
931 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in can_request_irq()
956 		pr_debug("No set_type function for IRQ %d (%s)\n",  in __irq_set_trigger()
993 		pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",  in __irq_set_trigger()
1002 int irq_set_parent(int irq, int parent_irq)  in irq_set_parent()  argument
1005 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in irq_set_parent()
1023 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)  in irq_default_primary_handler()  argument
1032 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)  in irq_nested_primary_handler()  argument
1034 	WARN(1, "Primary handler called for nested irq %d\n", irq);  in irq_nested_primary_handler()
1038 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)  in irq_forced_secondary_handler()  argument
1040 	WARN(1, "Secondary action handler called for irq %d\n", irq);  in irq_forced_secondary_handler()
1070  * Oneshot interrupts keep the irq line masked until the threaded
1089 	 * on the other CPU. If we unmask the irq line then the  in irq_finalize_oneshot()
1091 	 * to IRQS_INPROGRESS and the irq line is masked forever.  in irq_finalize_oneshot()
1172  * interrupts rely on the implicit bh/preempt disable of the hard irq
1184 	ret = action->thread_fn(action->irq, action->dev_id);  in irq_forced_thread_fn()
1205 	ret = action->thread_fn(action->irq, action->dev_id);  in irq_thread_fn()
1230 	pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",  in irq_thread_dtor()
1231 	       tsk->comm, tsk->pid, action->irq);  in irq_thread_dtor()
1234 	desc = irq_to_desc(action->irq);  in irq_thread_dtor()
1290 	struct irq_desc *desc = irq_to_desc(action->irq);  in irq_thread()
1332  *	irq_wake_thread - wake the irq thread for the action identified by dev_id
1333  *	@irq:		Interrupt line
1337 void irq_wake_thread(unsigned int irq, void *dev_id)  in irq_wake_thread()  argument
1339 	struct irq_desc *desc = irq_to_desc(irq);  in irq_wake_thread()
1387 		new->secondary->irq = new->irq;  in irq_setup_forced_threading()
1448 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)  in setup_irq_thread()  argument
1453 		t = kthread_create(irq_thread, new, "irq/%d-%s", irq,  in setup_irq_thread()
1456 		t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,  in setup_irq_thread()
1497 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)  in __setup_irq()  argument
1511 	new->irq = irq;  in __setup_irq()
1550 		ret = setup_irq_thread(new, irq, false);  in __setup_irq()
1554 			ret = setup_irq_thread(new->secondary, irq, true);  in __setup_irq()
1562 	 * underlying irq chip implementation, so a request for a  in __setup_irq()
1563 	 * threaded irq without a primary hard irq context handler  in __setup_irq()
1564 	 * requires the ONESHOT flag to be set. Some irq chips like  in __setup_irq()
1592 			pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",  in __setup_irq()
1593 			       new->name, irq, desc->irq_data.chip->name);  in __setup_irq()
1619 			pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",  in __setup_irq()
1620 				new->name, irq, desc->irq_data.chip->name);  in __setup_irq()
1646 		/* add new interrupt at end of irq queue */  in __setup_irq()
1684 		 * If no thread is woken by primary (hard irq context)  in __setup_irq()
1686 		 * also checked for zero to unmask the irq line in the  in __setup_irq()
1687 		 * affected hard irq flow handlers  in __setup_irq()
1704 		 * the irq lines is reenabled, but the device still  in __setup_irq()
1705 		 * has the level irq asserted. Rinse and repeat....  in __setup_irq()
1713 		pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",  in __setup_irq()
1714 		       new->name, irq);  in __setup_irq()
1761 		/* Exclude IRQ from balancing if requested */  in __setup_irq()
1788 			pr_warn("irq %d uses trigger mode %u; requested %u\n",  in __setup_irq()
1789 				irq, omsk, nmsk);  in __setup_irq()
1796 	/* Reset broken irq detection when installing new handler */  in __setup_irq()
1801 	 * Check whether we disabled the irq via the spurious handler  in __setup_irq()
1818 	register_irq_proc(irq, desc);  in __setup_irq()
1820 	register_handler_proc(irq, new);  in __setup_irq()
1825 		pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",  in __setup_irq()
1826 		       irq, new->flags, new->name, old->flags, old->name);  in __setup_irq()
1868 	unsigned irq = desc->irq_data.irq;  in __free_irq()  local
1872 	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);  in __free_irq()
1879 	 * There can be multiple actions per IRQ descriptor, find the right  in __free_irq()
1887 			WARN(1, "Trying to free already-free IRQ %d\n", irq);  in __free_irq()
1904 	/* If this was the last handler, shut down the IRQ line: */  in __free_irq()
1920 	 * callbacks above are synced out to the irq chips which hang  in __free_irq()
1929 	 * concurrent request_irq() of this irq so the release of resources  in __free_irq()
1934 	unregister_handler_proc(irq, action);  in __free_irq()
1945 	 * It's a shared IRQ -- the driver ought to be prepared for an IRQ  in __free_irq()
1950 	 *   'real' IRQ doesn't run in parallel with our fake. )  in __free_irq()
1954 		action->handler(irq, dev_id);  in __free_irq()
2004  *	@irq: Interrupt line to free
2009  *	On a shared IRQ the caller must ensure the interrupt is disabled
2011  *	does not return until any executing interrupts for this IRQ
2018 const void *free_irq(unsigned int irq, void *dev_id)  in free_irq()  argument
2020 	struct irq_desc *desc = irq_to_desc(irq);  in free_irq()
2044 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)  in __cleanup_nmi()  argument
2053 		unregister_handler_proc(irq, desc->action);  in __cleanup_nmi()
2070 const void *free_nmi(unsigned int irq, void *dev_id)  in free_nmi()  argument
2072 	struct irq_desc *desc = irq_to_desc(irq);  in free_nmi()
2084 		disable_nmi_nosync(irq);  in free_nmi()
2089 	devname = __cleanup_nmi(irq, desc);  in free_nmi()
2098  *	@irq: Interrupt line to allocate
2099  *	@handler: Function to be called when the IRQ occurs.
2103  *	@thread_fn: Function called from the irq handler thread
2104  *		    If NULL, no irq thread is created
2110  *	interrupt line and IRQ handling. From the point this
2116  *	If you want to set up a threaded irq handler for your device
2138 int request_threaded_irq(unsigned int irq, irq_handler_t handler,  in request_threaded_irq()  argument
2146 	if (irq == IRQ_NOTCONNECTED)  in request_threaded_irq()
2168 	desc = irq_to_desc(irq);  in request_threaded_irq()
2198 	retval = __setup_irq(irq, desc, action);  in request_threaded_irq()
2209 		 * It's a shared IRQ -- the driver ought to be prepared for it  in request_threaded_irq()
2211 		 * We disable the irq to make sure that a 'real' IRQ doesn't  in request_threaded_irq()
2216 		disable_irq(irq);  in request_threaded_irq()
2219 		handler(irq, dev_id);  in request_threaded_irq()
2222 		enable_irq(irq);  in request_threaded_irq()
2231  *	@irq: Interrupt line to allocate
2232  *	@handler: Function to be called when the IRQ occurs.
2239  *	interrupt line and IRQ handling. It selects either a
2246 int request_any_context_irq(unsigned int irq, irq_handler_t handler,  in request_any_context_irq()  argument
2252 	if (irq == IRQ_NOTCONNECTED)  in request_any_context_irq()
2255 	desc = irq_to_desc(irq);  in request_any_context_irq()
2260 		ret = request_threaded_irq(irq, NULL, handler,  in request_any_context_irq()
2265 	ret = request_irq(irq, handler, flags, name, dev_id);  in request_any_context_irq()
2272  *	@irq: Interrupt line to allocate
2273  *	@handler: Function to be called when the IRQ occurs.
2280  *	interrupt line and IRQ handling. It sets up the IRQ line
2283  *	An interrupt line delivering NMIs cannot be shared and IRQ handling
2296 int request_nmi(unsigned int irq, irq_handler_t handler,  in request_nmi()  argument
2304 	if (irq == IRQ_NOTCONNECTED)  in request_nmi()
2317 	desc = irq_to_desc(irq);  in request_nmi()
2339 	retval = __setup_irq(irq, desc, action);  in request_nmi()
2349 		__cleanup_nmi(irq, desc);  in request_nmi()
2366 void enable_percpu_irq(unsigned int irq, unsigned int type)  in enable_percpu_irq()  argument
2370 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in enable_percpu_irq()
2389 			WARN(1, "failed to set type for IRQ%d\n", irq);  in enable_percpu_irq()
2400 void enable_percpu_nmi(unsigned int irq, unsigned int type)  in enable_percpu_nmi()  argument
2402 	enable_percpu_irq(irq, type);  in enable_percpu_nmi()
2406  * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2407  * @irq:	Linux irq number to check for
2412 bool irq_percpu_is_enabled(unsigned int irq)  in irq_percpu_is_enabled()  argument
2419 	desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in irq_percpu_is_enabled()
2430 void disable_percpu_irq(unsigned int irq)  in disable_percpu_irq()  argument
2434 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in disable_percpu_irq()
2444 void disable_percpu_nmi(unsigned int irq)  in disable_percpu_nmi()  argument
2446 	disable_percpu_irq(irq);  in disable_percpu_nmi()
2452 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)  in __free_percpu_irq()  argument
2454 	struct irq_desc *desc = irq_to_desc(irq);  in __free_percpu_irq()
2458 	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);  in __free_percpu_irq()
2467 		WARN(1, "Trying to free already-free IRQ %d\n", irq);  in __free_percpu_irq()
2472 		WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",  in __free_percpu_irq()
2473 		     irq, cpumask_first(desc->percpu_enabled));  in __free_percpu_irq()
2484 	unregister_handler_proc(irq, action);  in __free_percpu_irq()
2497  *	@irq: Interrupt line to free
2502 void remove_percpu_irq(unsigned int irq, struct irqaction *act)  in remove_percpu_irq()  argument
2504 	struct irq_desc *desc = irq_to_desc(irq);  in remove_percpu_irq()
2507 	    __free_percpu_irq(irq, act->percpu_dev_id);  in remove_percpu_irq()
2512  *	@irq: Interrupt line to free
2518  *	until any executing interrupts for this IRQ have completed.
2522 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)  in free_percpu_irq()  argument
2524 	struct irq_desc *desc = irq_to_desc(irq);  in free_percpu_irq()
2530 	kfree(__free_percpu_irq(irq, dev_id));  in free_percpu_irq()
2535 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)  in free_percpu_nmi()  argument
2537 	struct irq_desc *desc = irq_to_desc(irq);  in free_percpu_nmi()
2545 	kfree(__free_percpu_irq(irq, dev_id));  in free_percpu_nmi()
2550  *	@irq: Interrupt line to setup
2555 int setup_percpu_irq(unsigned int irq, struct irqaction *act)  in setup_percpu_irq()  argument
2557 	struct irq_desc *desc = irq_to_desc(irq);  in setup_percpu_irq()
2567 	retval = __setup_irq(irq, desc, act);  in setup_percpu_irq()
2577  *	@irq: Interrupt line to allocate
2578  *	@handler: Function to be called when the IRQ occurs.
2592 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,  in __request_percpu_irq()  argument
2603 	desc = irq_to_desc(irq);  in __request_percpu_irq()
2626 	retval = __setup_irq(irq, desc, action);  in __request_percpu_irq()
2639  *	@irq: Interrupt line to allocate
2640  *	@handler: Function to be called when the IRQ occurs.
2658 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,  in request_percpu_nmi()  argument
2669 	desc = irq_to_desc(irq);  in request_percpu_nmi()
2695 	retval = __setup_irq(irq, desc, action);  in request_percpu_nmi()
2715  *	@irq: Interrupt line to prepare for NMI delivery
2726 int prepare_percpu_nmi(unsigned int irq)  in prepare_percpu_nmi()  argument
2734 	desc = irq_get_desc_lock(irq, &flags,  in prepare_percpu_nmi()
2740 		 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",  in prepare_percpu_nmi()
2741 		 irq)) {  in prepare_percpu_nmi()
2748 		pr_err("Failed to setup NMI delivery: irq %u\n", irq);  in prepare_percpu_nmi()
2758  *	teardown_percpu_nmi - undoes NMI setup of IRQ line
2759  *	@irq: Interrupt line from which CPU local NMI configuration should be
2764  *	IRQ line should not be enabled for the current CPU.
2769 void teardown_percpu_nmi(unsigned int irq)  in teardown_percpu_nmi()  argument
2776 	desc = irq_get_desc_lock(irq, &flags,  in teardown_percpu_nmi()
2815  *	@irq: Interrupt line that is forwarded to a VM
2826 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,  in irq_get_irqchip_state()  argument
2834 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_get_irqchip_state()
2849  *	@irq: Interrupt line that is forwarded to a VM
2859 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,  in irq_set_irqchip_state()  argument
2868 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_set_irqchip_state()
2900  * @irq:	The linux irq number
2904 bool irq_has_action(unsigned int irq)  in irq_has_action()  argument
2909 	res = irq_desc_has_action(irq_to_desc(irq));  in irq_has_action()
2916  * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2917  * @irq:	The linux irq number
2922 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)  in irq_check_status_bit()  argument
2928 	desc = irq_to_desc(irq);  in irq_check_status_bit()