genirq: fix regression in irqfixup, irqpoll
[linux-2.6.git] / kernel / irq / pm.c
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  */
24 void 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 }
41 EXPORT_SYMBOL_GPL(suspend_device_irqs);
42
43 static 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  */
67 static void irq_pm_syscore_resume(void)
68 {
69         resume_irqs(true);
70 }
71
72 static struct syscore_ops irq_pm_syscore_ops = {
73         .resume         = irq_pm_syscore_resume,
74 };
75
76 static int __init irq_pm_init_ops(void)
77 {
78         register_syscore_ops(&irq_pm_syscore_ops);
79         return 0;
80 }
81
82 device_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  */
91 void resume_device_irqs(void)
92 {
93         resume_irqs(false);
94 }
95 EXPORT_SYMBOL_GPL(resume_device_irqs);
96
97 /**
98  * check_wakeup_irqs - check if any wake-up interrupts are pending
99  */
100 int check_wakeup_irqs(void)
101 {
102         struct irq_desc *desc;
103         int irq;
104
105         for_each_irq_desc(irq, desc) {
106                 if (irqd_is_wakeup_set(&desc->irq_data)) {
107                         if (desc->istate & IRQS_PENDING)
108                                 return -EBUSY;
109                         continue;
110                 }
111                 /*
112                  * Check the non wakeup interrupts whether they need
113                  * to be masked before finally going into suspend
114                  * state. That's for hardware which has no wakeup
115                  * source configuration facility. The chip
116                  * implementation indicates that with
117                  * IRQCHIP_MASK_ON_SUSPEND.
118                  */
119                 if (desc->istate & IRQS_SUSPENDED &&
120                     irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
121                         mask_irq(desc);
122         }
123
124         return 0;
125 }