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Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +01001/*
2 * linux/kernel/irq/pm.c
3 *
4 * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5 *
6 * This file contains power management functions related to interrupts.
7 */
8
9#include <linux/irq.h>
10#include <linux/module.h>
11#include <linux/interrupt.h>
12
13#include "internals.h"
14
15/**
16 * suspend_device_irqs - disable all currently enabled interrupt lines
17 *
Rafael J. Wysockic71320d2009-07-05 00:22:34 +020018 * During system-wide suspend or hibernation device drivers need to be prevented
19 * from receiving interrupts and this function is provided for this purpose.
20 * It marks all interrupt lines in use, except for the timer ones, as disabled
Thomas Gleixnerc531e832011-02-08 12:44:58 +010021 * and sets the IRQS_SUSPENDED flag for each of them.
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010022 */
23void suspend_device_irqs(void)
24{
25 struct irq_desc *desc;
26 int irq;
27
28 for_each_irq_desc(irq, desc) {
29 unsigned long flags;
30
Thomas Gleixner239007b2009-11-17 16:46:45 +010031 raw_spin_lock_irqsave(&desc->lock, flags);
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010032 __disable_irq(desc, irq, true);
Thomas Gleixner239007b2009-11-17 16:46:45 +010033 raw_spin_unlock_irqrestore(&desc->lock, flags);
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010034 }
35
36 for_each_irq_desc(irq, desc)
Thomas Gleixnerc531e832011-02-08 12:44:58 +010037 if (desc->istate & IRQS_SUSPENDED)
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010038 synchronize_irq(irq);
39}
40EXPORT_SYMBOL_GPL(suspend_device_irqs);
41
42/**
43 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
44 *
45 * Enable all interrupt lines previously disabled by suspend_device_irqs() that
Thomas Gleixnerc531e832011-02-08 12:44:58 +010046 * have the IRQS_SUSPENDED flag set.
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010047 */
48void resume_device_irqs(void)
49{
50 struct irq_desc *desc;
51 int irq;
52
53 for_each_irq_desc(irq, desc) {
54 unsigned long flags;
55
Thomas Gleixner239007b2009-11-17 16:46:45 +010056 raw_spin_lock_irqsave(&desc->lock, flags);
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010057 __enable_irq(desc, irq, true);
Thomas Gleixner239007b2009-11-17 16:46:45 +010058 raw_spin_unlock_irqrestore(&desc->lock, flags);
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010059 }
60}
61EXPORT_SYMBOL_GPL(resume_device_irqs);
62
63/**
64 * check_wakeup_irqs - check if any wake-up interrupts are pending
65 */
66int check_wakeup_irqs(void)
67{
68 struct irq_desc *desc;
69 int irq;
70
Thomas Gleixnerd209a692011-03-11 21:22:14 +010071 for_each_irq_desc(irq, desc) {
72 if (irqd_is_wakeup_set(&desc->irq_data)) {
73 if (desc->istate & IRQS_PENDING)
74 return -EBUSY;
75 continue;
76 }
77 /*
78 * Check the non wakeup interrupts whether they need
79 * to be masked before finally going into suspend
80 * state. That's for hardware which has no wakeup
81 * source configuration facility. The chip
82 * implementation indicates that with
83 * IRQCHIP_MASK_ON_SUSPEND.
84 */
85 if (desc->istate & IRQS_SUSPENDED &&
86 irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
87 mask_irq(desc);
88 }
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +010089
90 return 0;
91}