pm.c

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/*
 * linux/kernel/irq/pm.c
 *
 * Copyright (C) 2009 Rafael J. Wysocki <[email protected]>, 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"

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);
    }
}

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);

void resume_device_irqs(void)
{
    resume_irqs(false);
}
EXPORT_SYMBOL_GPL(resume_device_irqs);

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;
}