/* * linux/kernel/irq/pm.c * * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. * * This file contains power management functions related to interrupts. */ #include <linux/irq.h>#include <linux/module.h>#include <linux/interrupt.h>#include <linux/syscore_ops.h> #include "internals.h" /** * suspend_device_irqs - disable all currently enabled interrupt lines * * During system-wide suspend or hibernation device drivers need to be prevented * from receiving interrupts and this function is provided for this purpose. * It marks all interrupt lines in use, except for the timer ones, as disabled * and sets the IRQS_SUSPENDED flag for each of them. */void suspend_device_irqs(void){	struct irq_desc *desc;	int irq; 	for_each_irq_desc(irq, desc) {		unsigned long flags; 		raw_spin_lock_irqsave(&desc->lock, flags);		__disable_irq(desc, irq, true);		raw_spin_unlock_irqrestore(&desc->lock, flags);	} 	for_each_irq_desc(irq, desc)		if (desc->istate & IRQS_SUSPENDED)			synchronize_irq(irq);}EXPORT_SYMBOL_GPL(suspend_device_irqs); static void resume_irqs(bool want_early){	struct irq_desc *desc;	int irq; 	for_each_irq_desc(irq, desc) {		unsigned long flags;		bool is_early = desc->action &&			desc->action->flags & IRQF_EARLY_RESUME; 		if (is_early != want_early)			continue; 		raw_spin_lock_irqsave(&desc->lock, flags);		__enable_irq(desc, irq, true);		raw_spin_unlock_irqrestore(&desc->lock, flags);	}} /** * irq_pm_syscore_ops - enable interrupt lines early * * Enable all interrupt lines with %IRQF_EARLY_RESUME set. */static void irq_pm_syscore_resume(void){	resume_irqs(true);} static struct syscore_ops irq_pm_syscore_ops = {	.resume		= irq_pm_syscore_resume,}; static int __init irq_pm_init_ops(void){	register_syscore_ops(&irq_pm_syscore_ops);	return 0;} device_initcall(irq_pm_init_ops); /** * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() * * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag * set as well as those with %IRQF_FORCE_RESUME. */void resume_device_irqs(void){	resume_irqs(false);}EXPORT_SYMBOL_GPL(resume_device_irqs); /** * check_wakeup_irqs - check if any wake-up interrupts are pending */int check_wakeup_irqs(void){	struct irq_desc *desc;	int irq; 	for_each_irq_desc(irq, desc) {		/*		 * Only interrupts which are marked as wakeup source		 * and have not been disabled before the suspend check		 * can abort suspend.		 */		if (irqd_is_wakeup_set(&desc->irq_data)) {			if (desc->depth == 1 && desc->istate & IRQS_PENDING)				return -EBUSY;			continue;		}		/*		 * Check the non wakeup interrupts whether they need		 * to be masked before finally going into suspend		 * state. That's for hardware which has no wakeup		 * source configuration facility. The chip		 * implementation indicates that with		 * IRQCHIP_MASK_ON_SUSPEND.		 */		if (desc->istate & IRQS_SUSPENDED &&		    irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)			mask_irq(desc);	} 	return 0;}