blob: 0067abb3a9a98696c19e334c75d6600580c949db [file] [log] [blame]
/*
* 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 "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 IRQ_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;
spin_lock_irqsave(&desc->lock, flags);
__disable_irq(desc, irq, true);
spin_unlock_irqrestore(&desc->lock, flags);
}
for_each_irq_desc(irq, desc)
if (desc->status & IRQ_SUSPENDED)
synchronize_irq(irq);
}
EXPORT_SYMBOL_GPL(suspend_device_irqs);
/**
* resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
*
* Enable all interrupt lines previously disabled by suspend_device_irqs() that
* have the IRQ_SUSPENDED flag set.
*/
void resume_device_irqs(void)
{
struct irq_desc *desc;
int irq;
for_each_irq_desc(irq, desc) {
unsigned long flags;
spin_lock_irqsave(&desc->lock, flags);
__enable_irq(desc, irq, true);
spin_unlock_irqrestore(&desc->lock, flags);
}
}
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)
if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING))
return -EBUSY;
return 0;
}