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1/*
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#include <linux/syscore_ops.h>
13
14#include "internals.h"
15
16/**
17 * suspend_device_irqs - disable all currently enabled interrupt lines
18 *
19 * During system-wide suspend or hibernation device drivers need to be prevented
20 * from receiving interrupts and this function is provided for this purpose.
21 * It marks all interrupt lines in use, except for the timer ones, as disabled
22 * and sets the IRQS_SUSPENDED flag for each of them.
23 */
24void suspend_device_irqs(void)
25{
26 struct irq_desc *desc;
27 int irq;
28
29 for_each_irq_desc(irq, desc) {
30 unsigned long flags;
31
32 raw_spin_lock_irqsave(&desc->lock, flags);
33 __disable_irq(desc, irq, true);
34 raw_spin_unlock_irqrestore(&desc->lock, flags);
35 }
36
37 for_each_irq_desc(irq, desc)
38 if (desc->istate & IRQS_SUSPENDED)
39 synchronize_irq(irq);
40}
41EXPORT_SYMBOL_GPL(suspend_device_irqs);
42
43static void resume_irqs(bool want_early)
44{
45 struct irq_desc *desc;
46 int irq;
47
48 for_each_irq_desc(irq, desc) {
49 unsigned long flags;
50 bool is_early = desc->action &&
51 desc->action->flags & IRQF_EARLY_RESUME;
52
53 if (!is_early && want_early)
54 continue;
55
56 raw_spin_lock_irqsave(&desc->lock, flags);
57 __enable_irq(desc, irq, true);
58 raw_spin_unlock_irqrestore(&desc->lock, flags);
59 }
60}
61
62/**
63 * irq_pm_syscore_ops - enable interrupt lines early
64 *
65 * Enable all interrupt lines with %IRQF_EARLY_RESUME set.
66 */
67static void irq_pm_syscore_resume(void)
68{
69 resume_irqs(true);
70}
71
72static struct syscore_ops irq_pm_syscore_ops = {
73 .resume = irq_pm_syscore_resume,
74};
75
76static int __init irq_pm_init_ops(void)
77{
78 register_syscore_ops(&irq_pm_syscore_ops);
79 return 0;
80}
81
82device_initcall(irq_pm_init_ops);
83
84/**
85 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
86 *
87 * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously
88 * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag
89 * set as well as those with %IRQF_FORCE_RESUME.
90 */
91void resume_device_irqs(void)
92{
93 resume_irqs(false);
94}
95EXPORT_SYMBOL_GPL(resume_device_irqs);
96
97/**
98 * check_wakeup_irqs - check if any wake-up interrupts are pending
99 */
100int check_wakeup_irqs(void)
101{
102 struct irq_desc *desc;
103 int irq;
104
105 for_each_irq_desc(irq, desc) {
106 /*
107 * Only interrupts which are marked as wakeup source
108 * and have not been disabled before the suspend check
109 * can abort suspend.
110 */
111 if (irqd_is_wakeup_set(&desc->irq_data)) {
112 if (desc->depth == 1 && desc->istate & IRQS_PENDING)
113 return -EBUSY;
114 continue;
115 }
116 /*
117 * Check the non wakeup interrupts whether they need
118 * to be masked before finally going into suspend
119 * state. That's for hardware which has no wakeup
120 * source configuration facility. The chip
121 * implementation indicates that with
122 * IRQCHIP_MASK_ON_SUSPEND.
123 */
124 if (desc->istate & IRQS_SUSPENDED &&
125 irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
126 mask_irq(desc);
127 }
128
129 return 0;
130}
1/*
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 *
18 * 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
21 * and sets the IRQS_SUSPENDED flag for each of them.
22 */
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
31 raw_spin_lock_irqsave(&desc->lock, flags);
32 __disable_irq(desc, irq, true);
33 raw_spin_unlock_irqrestore(&desc->lock, flags);
34 }
35
36 for_each_irq_desc(irq, desc)
37 if (desc->istate & IRQS_SUSPENDED)
38 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
46 * have the IRQS_SUSPENDED flag set.
47 */
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
56 raw_spin_lock_irqsave(&desc->lock, flags);
57 __enable_irq(desc, irq, true);
58 raw_spin_unlock_irqrestore(&desc->lock, flags);
59 }
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
71 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 }
89
90 return 0;
91}