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()
122  *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
123  *	@irq: interrupt number to wait for
125  *	This function waits for any pending IRQ handlers for this interrupt
127  *	holding a resource the IRQ handler may need you will deadlock.
130  *	an interrupt thread is associated to @irq.
132  *	It optionally makes sure (when the irq chip supports that method)
136 void synchronize_irq(unsigned int irq)  in synchronize_irq()  argument
138 	struct irq_desc *desc = irq_to_desc(irq);  in synchronize_irq()
157  *	irq_can_set_affinity - Check if the affinity of a given irq can be set
158  *	@irq:		Interrupt to check
161 int irq_can_set_affinity(unsigned int irq)  in irq_can_set_affinity()  argument
163 	return __irq_can_set_affinity(irq_to_desc(irq));  in irq_can_set_affinity()
167  * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
168  * @irq:	Interrupt to check
173 bool irq_can_set_affinity_usr(unsigned int irq)  in irq_can_set_affinity_usr()  argument
175 	struct irq_desc *desc = irq_to_desc(irq);  in irq_can_set_affinity_usr()
182  *	irq_set_thread_affinity - Notify irq threads to adjust affinity
183  *	@desc:		irq descriptor which has affinity changed
214 	pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",  in irq_validate_effective_affinity()
215 		     chip->name, data->irq);  in irq_validate_effective_affinity()
335 	 * Handle irq chips which can handle affinity only in activated  in irq_set_affinity_deactivated()
388  * @irq:	The interrupt number to update
395  * for when the kernel is configured for generic IRQ reservation mode (in
401 int irq_update_affinity_desc(unsigned int irq,  in irq_update_affinity_desc()  argument
416 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_update_affinity_desc()
456 static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,  in __irq_set_affinity()  argument
459 	struct irq_desc *desc = irq_to_desc(irq);  in __irq_set_affinity()
473  * irq_set_affinity - Set the irq affinity of a given irq
474  * @irq:	Interrupt to set affinity
479 int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)  in irq_set_affinity()  argument
481 	return __irq_set_affinity(irq, cpumask, false);  in irq_set_affinity()
486  * irq_force_affinity - Force the irq affinity of a given irq
487  * @irq:	Interrupt to set affinity
496 int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)  in irq_force_affinity()  argument
498 	return __irq_set_affinity(irq, cpumask, true);  in irq_force_affinity()
502 int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,  in __irq_apply_affinity_hint()  argument
506 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in __irq_apply_affinity_hint()
513 		__irq_set_affinity(irq, m, false);  in __irq_apply_affinity_hint()
522 	struct irq_desc *desc = irq_to_desc(notify->irq);  in irq_affinity_notify()
544  *	irq_set_affinity_notifier - control notification of IRQ affinity changes
545  *	@irq:		Interrupt for which to enable/disable notification
551  *	after the IRQ is allocated and must be disabled before the IRQ is
555 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)  in irq_set_affinity_notifier()  argument
557 	struct irq_desc *desc = irq_to_desc(irq);  in irq_set_affinity_notifier()
569 		notify->irq = irq;  in irq_set_affinity_notifier()
647  *	@irq: interrupt number to set affinity
652  *	affinity for an irq. The vCPU specific data is passed from
656 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)  in irq_set_vcpu_affinity()  argument
659 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in irq_set_vcpu_affinity()
693 static int __disable_irq_nosync(unsigned int irq)  in __disable_irq_nosync()  argument
696 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in __disable_irq_nosync()
706  *	disable_irq_nosync - disable an irq without waiting
707  *	@irq: Interrupt to disable
712  *	instances of the IRQ handler have completed before returning.
714  *	This function may be called from IRQ context.
716 void disable_irq_nosync(unsigned int irq)  in disable_irq_nosync()  argument
718 	__disable_irq_nosync(irq);  in disable_irq_nosync()
723  *	disable_irq - disable an irq and wait for completion
724  *	@irq: Interrupt to disable
728  *	This function waits for any pending IRQ handlers for this interrupt
730  *	holding a resource the IRQ handler may need you will deadlock.
733  *	an interrupt thread is associated to @irq.
736 void disable_irq(unsigned int irq)  in disable_irq()  argument
739 	if (!__disable_irq_nosync(irq))  in disable_irq()
740 		synchronize_irq(irq);  in disable_irq()
745  *	disable_hardirq - disables an irq and waits for hardirq completion
746  *	@irq: Interrupt to disable
750  *	This function waits for any pending hard IRQ handlers for this
752  *	holding a resource the hard IRQ handler may need you will deadlock.
759  *	This function may be called - with care - from IRQ context.
761 bool disable_hardirq(unsigned int irq)  in disable_hardirq()  argument
763 	if (!__disable_irq_nosync(irq))  in disable_hardirq()
764 		return synchronize_hardirq(irq);  in disable_hardirq()
772  *	@irq: Interrupt to disable
778  *	instances of the IRQ handler have completed before returning.
780 void disable_nmi_nosync(unsigned int irq)  in disable_nmi_nosync()  argument
782 	disable_irq_nosync(irq);  in disable_nmi_nosync()
790 		WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",  in __enable_irq()
796 		/* Prevent probing on this irq: */  in __enable_irq()
818  *	enable_irq - enable handling of an irq
819  *	@irq: Interrupt to enable
823  *	IRQ line is re-enabled.
825  *	This function may be called from IRQ context only when
828 void enable_irq(unsigned int irq)  in enable_irq()  argument
831 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in enable_irq()
836 		 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))  in enable_irq()
847  *	@irq: Interrupt to enable
852  *	IRQ line is re-enabled.
854 void enable_nmi(unsigned int irq)  in enable_nmi()  argument
856 	enable_irq(irq);  in enable_nmi()
859 static int set_irq_wake_real(unsigned int irq, unsigned int on)  in set_irq_wake_real()  argument
861 	struct irq_desc *desc = irq_to_desc(irq);  in set_irq_wake_real()
874  *	irq_set_irq_wake - control irq power management wakeup
875  *	@irq:	interrupt to control
882  *	Wakeup mode lets this IRQ wake the system from sleep
885  *	Note: irq enable/disable state is completely orthogonal
886  *	to the enable/disable state of irq wake. An irq can be
888  *	long as the irq has wake enabled. If this does not hold,
889  *	then the underlying irq chip and the related driver need
892 int irq_set_irq_wake(unsigned int irq, unsigned int on)  in irq_set_irq_wake()  argument
895 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);  in irq_set_irq_wake()
912 			ret = set_irq_wake_real(irq, on);  in irq_set_irq_wake()
920 			WARN(1, "Unbalanced IRQ %d wake disable\n", irq);  in irq_set_irq_wake()
922 			ret = set_irq_wake_real(irq, on);  in irq_set_irq_wake()
938  * particular irq has been exclusively allocated or is available
941 int can_request_irq(unsigned int irq, unsigned long irqflags)  in can_request_irq()  argument
944 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in can_request_irq()
969 		pr_debug("No set_type function for IRQ %d (%s)\n",  in __irq_set_trigger()
1006 		pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",  in __irq_set_trigger()
1015 int irq_set_parent(int irq, int parent_irq)  in irq_set_parent()  argument
1018 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);  in irq_set_parent()
1036 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)  in irq_default_primary_handler()  argument
1045 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)  in irq_nested_primary_handler()  argument
1047 	WARN(1, "Primary handler called for nested irq %d\n", irq);  in irq_nested_primary_handler()
1051 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)  in irq_forced_secondary_handler()  argument
1053 	WARN(1, "Secondary action handler called for irq %d\n", irq);  in irq_forced_secondary_handler()
1130  * Oneshot interrupts keep the irq line masked until the threaded
1149 	 * on the other CPU. If we unmask the irq line then the  in irq_finalize_oneshot()
1151 	 * to IRQS_INPROGRESS and the irq line is masked forever.  in irq_finalize_oneshot()
1186  * interrupts rely on the implicit bh/preempt disable of the hard irq
1198 	ret = action->thread_fn(action->irq, action->dev_id);  in irq_forced_thread_fn()
1219 	ret = action->thread_fn(action->irq, action->dev_id);  in irq_thread_fn()
1244 	pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",  in irq_thread_dtor()
1245 	       tsk->comm, tsk->pid, action->irq);  in irq_thread_dtor()
1248 	desc = irq_to_desc(action->irq);  in irq_thread_dtor()
1304 	struct irq_desc *desc = irq_to_desc(action->irq);  in irq_thread()
1342  *	irq_wake_thread - wake the irq thread for the action identified by dev_id
1343  *	@irq:		Interrupt line
1347 void irq_wake_thread(unsigned int irq, void *dev_id)  in irq_wake_thread()  argument
1349 	struct irq_desc *desc = irq_to_desc(irq);  in irq_wake_thread()
1397 		new->secondary->irq = new->irq;  in irq_setup_forced_threading()
1458 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)  in setup_irq_thread()  argument
1463 		t = kthread_create(irq_thread, new, "irq/%d-%s", irq,  in setup_irq_thread()
1466 		t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,  in setup_irq_thread()
1507 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)  in __setup_irq()  argument
1521 	new->irq = irq;  in __setup_irq()
1560 		ret = setup_irq_thread(new, irq, false);  in __setup_irq()
1564 			ret = setup_irq_thread(new->secondary, irq, true);  in __setup_irq()
1572 	 * underlying irq chip implementation, so a request for a  in __setup_irq()
1573 	 * threaded irq without a primary hard irq context handler  in __setup_irq()
1574 	 * requires the ONESHOT flag to be set. Some irq chips like  in __setup_irq()
1602 			pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",  in __setup_irq()
1603 			       new->name, irq, desc->irq_data.chip->name);  in __setup_irq()
1629 			pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",  in __setup_irq()
1630 				new->name, irq, desc->irq_data.chip->name);  in __setup_irq()
1661 		/* add new interrupt at end of irq queue */  in __setup_irq()
1699 		 * If no thread is woken by primary (hard irq context)  in __setup_irq()
1701 		 * also checked for zero to unmask the irq line in the  in __setup_irq()
1702 		 * affected hard irq flow handlers  in __setup_irq()
1719 		 * the irq lines is reenabled, but the device still  in __setup_irq()
1720 		 * has the level irq asserted. Rinse and repeat....  in __setup_irq()
1728 		pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",  in __setup_irq()
1729 		       new->name, irq);  in __setup_irq()
1776 		/* Exclude IRQ from balancing if requested */  in __setup_irq()
1803 			pr_warn("irq %d uses trigger mode %u; requested %u\n",  in __setup_irq()
1804 				irq, omsk, nmsk);  in __setup_irq()
1811 	/* Reset broken irq detection when installing new handler */  in __setup_irq()
1816 	 * Check whether we disabled the irq via the spurious handler  in __setup_irq()
1833 	register_irq_proc(irq, desc);  in __setup_irq()
1835 	register_handler_proc(irq, new);  in __setup_irq()
1840 		pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",  in __setup_irq()
1841 		       irq, new->flags, new->name, old->flags, old->name);  in __setup_irq()
1881 	unsigned irq = desc->irq_data.irq;  in __free_irq()  local
1885 	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);  in __free_irq()
1892 	 * There can be multiple actions per IRQ descriptor, find the right  in __free_irq()
1900 			WARN(1, "Trying to free already-free IRQ %d\n", irq);  in __free_irq()
1917 	/* If this was the last handler, shut down the IRQ line: */  in __free_irq()
1933 	 * callbacks above are synced out to the irq chips which hang  in __free_irq()
1942 	 * concurrent request_irq() of this irq so the release of resources  in __free_irq()
1947 	unregister_handler_proc(irq, action);  in __free_irq()
1958 	 * It's a shared IRQ -- the driver ought to be prepared for an IRQ  in __free_irq()
1963 	 *   'real' IRQ doesn't run in parallel with our fake. )  in __free_irq()
1967 		action->handler(irq, dev_id);  in __free_irq()
2014  *	@irq: Interrupt line to free
2019  *	On a shared IRQ the caller must ensure the interrupt is disabled
2021  *	does not return until any executing interrupts for this IRQ
2028 const void *free_irq(unsigned int irq, void *dev_id)  in free_irq()  argument
2030 	struct irq_desc *desc = irq_to_desc(irq);  in free_irq()
2054 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)  in __cleanup_nmi()  argument
2063 		unregister_handler_proc(irq, desc->action);  in __cleanup_nmi()
2080 const void *free_nmi(unsigned int irq, void *dev_id)  in free_nmi()  argument
2082 	struct irq_desc *desc = irq_to_desc(irq);  in free_nmi()
2094 		disable_nmi_nosync(irq);  in free_nmi()
2099 	devname = __cleanup_nmi(irq, desc);  in free_nmi()
2108  *	@irq: Interrupt line to allocate
2109  *	@handler: Function to be called when the IRQ occurs.
2113  *	@thread_fn: Function called from the irq handler thread
2114  *		    If NULL, no irq thread is created
2120  *	interrupt line and IRQ handling. From the point this
2126  *	If you want to set up a threaded irq handler for your device
2148 int request_threaded_irq(unsigned int irq, irq_handler_t handler,  in request_threaded_irq()  argument
2156 	if (irq == IRQ_NOTCONNECTED)  in request_threaded_irq()
2178 	desc = irq_to_desc(irq);  in request_threaded_irq()
2208 	retval = __setup_irq(irq, desc, action);  in request_threaded_irq()
2219 		 * It's a shared IRQ -- the driver ought to be prepared for it  in request_threaded_irq()
2221 		 * We disable the irq to make sure that a 'real' IRQ doesn't  in request_threaded_irq()
2226 		disable_irq(irq);  in request_threaded_irq()
2229 		handler(irq, dev_id);  in request_threaded_irq()
2232 		enable_irq(irq);  in request_threaded_irq()
2241  *	@irq: Interrupt line to allocate
2242  *	@handler: Function to be called when the IRQ occurs.
2249  *	interrupt line and IRQ handling. It selects either a
2256 int request_any_context_irq(unsigned int irq, irq_handler_t handler,  in request_any_context_irq()  argument
2262 	if (irq == IRQ_NOTCONNECTED)  in request_any_context_irq()
2265 	desc = irq_to_desc(irq);  in request_any_context_irq()
2270 		ret = request_threaded_irq(irq, NULL, handler,  in request_any_context_irq()
2275 	ret = request_irq(irq, handler, flags, name, dev_id);  in request_any_context_irq()
2282  *	@irq: Interrupt line to allocate
2283  *	@handler: Function to be called when the IRQ occurs.
2290  *	interrupt line and IRQ handling. It sets up the IRQ line
2293  *	An interrupt line delivering NMIs cannot be shared and IRQ handling
2306 int request_nmi(unsigned int irq, irq_handler_t handler,  in request_nmi()  argument
2314 	if (irq == IRQ_NOTCONNECTED)  in request_nmi()
2327 	desc = irq_to_desc(irq);  in request_nmi()
2349 	retval = __setup_irq(irq, desc, action);  in request_nmi()
2359 		__cleanup_nmi(irq, desc);  in request_nmi()
2376 void enable_percpu_irq(unsigned int irq, unsigned int type)  in enable_percpu_irq()  argument
2380 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in enable_percpu_irq()
2399 			WARN(1, "failed to set type for IRQ%d\n", irq);  in enable_percpu_irq()
2410 void enable_percpu_nmi(unsigned int irq, unsigned int type)  in enable_percpu_nmi()  argument
2412 	enable_percpu_irq(irq, type);  in enable_percpu_nmi()
2416  * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2417  * @irq:	Linux irq number to check for
2422 bool irq_percpu_is_enabled(unsigned int irq)  in irq_percpu_is_enabled()  argument
2429 	desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in irq_percpu_is_enabled()
2440 void disable_percpu_irq(unsigned int irq)  in disable_percpu_irq()  argument
2444 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);  in disable_percpu_irq()
2454 void disable_percpu_nmi(unsigned int irq)  in disable_percpu_nmi()  argument
2456 	disable_percpu_irq(irq);  in disable_percpu_nmi()
2462 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)  in __free_percpu_irq()  argument
2464 	struct irq_desc *desc = irq_to_desc(irq);  in __free_percpu_irq()
2468 	WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);  in __free_percpu_irq()
2477 		WARN(1, "Trying to free already-free IRQ %d\n", irq);  in __free_percpu_irq()
2482 		WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",  in __free_percpu_irq()
2483 		     irq, cpumask_first(desc->percpu_enabled));  in __free_percpu_irq()
2494 	unregister_handler_proc(irq, action);  in __free_percpu_irq()
2507  *	@irq: Interrupt line to free
2512 void remove_percpu_irq(unsigned int irq, struct irqaction *act)  in remove_percpu_irq()  argument
2514 	struct irq_desc *desc = irq_to_desc(irq);  in remove_percpu_irq()
2517 	    __free_percpu_irq(irq, act->percpu_dev_id);  in remove_percpu_irq()
2522  *	@irq: Interrupt line to free
2528  *	until any executing interrupts for this IRQ have completed.
2532 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)  in free_percpu_irq()  argument
2534 	struct irq_desc *desc = irq_to_desc(irq);  in free_percpu_irq()
2540 	kfree(__free_percpu_irq(irq, dev_id));  in free_percpu_irq()
2545 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)  in free_percpu_nmi()  argument
2547 	struct irq_desc *desc = irq_to_desc(irq);  in free_percpu_nmi()
2555 	kfree(__free_percpu_irq(irq, dev_id));  in free_percpu_nmi()
2560  *	@irq: Interrupt line to setup
2565 int setup_percpu_irq(unsigned int irq, struct irqaction *act)  in setup_percpu_irq()  argument
2567 	struct irq_desc *desc = irq_to_desc(irq);  in setup_percpu_irq()
2577 	retval = __setup_irq(irq, desc, act);  in setup_percpu_irq()
2587  *	@irq: Interrupt line to allocate
2588  *	@handler: Function to be called when the IRQ occurs.
2602 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,  in __request_percpu_irq()  argument
2613 	desc = irq_to_desc(irq);  in __request_percpu_irq()
2636 	retval = __setup_irq(irq, desc, action);  in __request_percpu_irq()
2649  *	@irq: Interrupt line to allocate
2650  *	@handler: Function to be called when the IRQ occurs.
2668 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,  in request_percpu_nmi()  argument
2679 	desc = irq_to_desc(irq);  in request_percpu_nmi()
2705 	retval = __setup_irq(irq, desc, action);  in request_percpu_nmi()
2725  *	@irq: Interrupt line to prepare for NMI delivery
2736 int prepare_percpu_nmi(unsigned int irq)  in prepare_percpu_nmi()  argument
2744 	desc = irq_get_desc_lock(irq, &flags,  in prepare_percpu_nmi()
2750 		 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",  in prepare_percpu_nmi()
2751 		 irq)) {  in prepare_percpu_nmi()
2758 		pr_err("Failed to setup NMI delivery: irq %u\n", irq);  in prepare_percpu_nmi()
2768  *	teardown_percpu_nmi - undoes NMI setup of IRQ line
2769  *	@irq: Interrupt line from which CPU local NMI configuration should be
2774  *	IRQ line should not be enabled for the current CPU.
2779 void teardown_percpu_nmi(unsigned int irq)  in teardown_percpu_nmi()  argument
2786 	desc = irq_get_desc_lock(irq, &flags,  in teardown_percpu_nmi()
2825  *	@irq: Interrupt line that is forwarded to a VM
2836 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,  in irq_get_irqchip_state()  argument
2844 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_get_irqchip_state()
2859  *	@irq: Interrupt line that is forwarded to a VM
2869 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,  in irq_set_irqchip_state()  argument
2878 	desc = irq_get_desc_buslock(irq, &flags, 0);  in irq_set_irqchip_state()
2910  * @irq:	The linux irq number
2914 bool irq_has_action(unsigned int irq)  in irq_has_action()  argument
2919 	res = irq_desc_has_action(irq_to_desc(irq));  in irq_has_action()
2926  * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2927  * @irq:	The linux irq number
2932 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)  in irq_check_status_bit()  argument
2938 	desc = irq_to_desc(irq);  in irq_check_status_bit()