Loading...
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/suspend.h>
13#include <linux/syscore_ops.h>
14
15#include "internals.h"
16
17bool irq_pm_check_wakeup(struct irq_desc *desc)
18{
19 if (irqd_is_wakeup_armed(&desc->irq_data)) {
20 irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
21 desc->istate |= IRQS_SUSPENDED | IRQS_PENDING;
22 desc->depth++;
23 irq_disable(desc);
24 pm_system_irq_wakeup(irq_desc_get_irq(desc));
25 return true;
26 }
27 return false;
28}
29
30/*
31 * Called from __setup_irq() with desc->lock held after @action has
32 * been installed in the action chain.
33 */
34void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action)
35{
36 desc->nr_actions++;
37
38 if (action->flags & IRQF_FORCE_RESUME)
39 desc->force_resume_depth++;
40
41 WARN_ON_ONCE(desc->force_resume_depth &&
42 desc->force_resume_depth != desc->nr_actions);
43
44 if (action->flags & IRQF_NO_SUSPEND)
45 desc->no_suspend_depth++;
46 else if (action->flags & IRQF_COND_SUSPEND)
47 desc->cond_suspend_depth++;
48
49 WARN_ON_ONCE(desc->no_suspend_depth &&
50 (desc->no_suspend_depth +
51 desc->cond_suspend_depth) != desc->nr_actions);
52}
53
54/*
55 * Called from __free_irq() with desc->lock held after @action has
56 * been removed from the action chain.
57 */
58void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action)
59{
60 desc->nr_actions--;
61
62 if (action->flags & IRQF_FORCE_RESUME)
63 desc->force_resume_depth--;
64
65 if (action->flags & IRQF_NO_SUSPEND)
66 desc->no_suspend_depth--;
67 else if (action->flags & IRQF_COND_SUSPEND)
68 desc->cond_suspend_depth--;
69}
70
71static bool suspend_device_irq(struct irq_desc *desc)
72{
73 if (!desc->action || irq_desc_is_chained(desc) ||
74 desc->no_suspend_depth)
75 return false;
76
77 if (irqd_is_wakeup_set(&desc->irq_data)) {
78 irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED);
79 /*
80 * We return true here to force the caller to issue
81 * synchronize_irq(). We need to make sure that the
82 * IRQD_WAKEUP_ARMED is visible before we return from
83 * suspend_device_irqs().
84 */
85 return true;
86 }
87
88 desc->istate |= IRQS_SUSPENDED;
89 __disable_irq(desc);
90
91 /*
92 * Hardware which has no wakeup source configuration facility
93 * requires that the non wakeup interrupts are masked at the
94 * chip level. The chip implementation indicates that with
95 * IRQCHIP_MASK_ON_SUSPEND.
96 */
97 if (irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
98 mask_irq(desc);
99 return true;
100}
101
102/**
103 * suspend_device_irqs - disable all currently enabled interrupt lines
104 *
105 * During system-wide suspend or hibernation device drivers need to be
106 * prevented from receiving interrupts and this function is provided
107 * for this purpose.
108 *
109 * So we disable all interrupts and mark them IRQS_SUSPENDED except
110 * for those which are unused, those which are marked as not
111 * suspendable via an interrupt request with the flag IRQF_NO_SUSPEND
112 * set and those which are marked as active wakeup sources.
113 *
114 * The active wakeup sources are handled by the flow handler entry
115 * code which checks for the IRQD_WAKEUP_ARMED flag, suspends the
116 * interrupt and notifies the pm core about the wakeup.
117 */
118void suspend_device_irqs(void)
119{
120 struct irq_desc *desc;
121 int irq;
122
123 for_each_irq_desc(irq, desc) {
124 unsigned long flags;
125 bool sync;
126
127 if (irq_settings_is_nested_thread(desc))
128 continue;
129 raw_spin_lock_irqsave(&desc->lock, flags);
130 sync = suspend_device_irq(desc);
131 raw_spin_unlock_irqrestore(&desc->lock, flags);
132
133 if (sync)
134 synchronize_irq(irq);
135 }
136}
137EXPORT_SYMBOL_GPL(suspend_device_irqs);
138
139static void resume_irq(struct irq_desc *desc)
140{
141 irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
142
143 if (desc->istate & IRQS_SUSPENDED)
144 goto resume;
145
146 /* Force resume the interrupt? */
147 if (!desc->force_resume_depth)
148 return;
149
150 /* Pretend that it got disabled ! */
151 desc->depth++;
152resume:
153 desc->istate &= ~IRQS_SUSPENDED;
154 __enable_irq(desc);
155}
156
157static void resume_irqs(bool want_early)
158{
159 struct irq_desc *desc;
160 int irq;
161
162 for_each_irq_desc(irq, desc) {
163 unsigned long flags;
164 bool is_early = desc->action &&
165 desc->action->flags & IRQF_EARLY_RESUME;
166
167 if (!is_early && want_early)
168 continue;
169 if (irq_settings_is_nested_thread(desc))
170 continue;
171
172 raw_spin_lock_irqsave(&desc->lock, flags);
173 resume_irq(desc);
174 raw_spin_unlock_irqrestore(&desc->lock, flags);
175 }
176}
177
178/**
179 * irq_pm_syscore_ops - enable interrupt lines early
180 *
181 * Enable all interrupt lines with %IRQF_EARLY_RESUME set.
182 */
183static void irq_pm_syscore_resume(void)
184{
185 resume_irqs(true);
186}
187
188static struct syscore_ops irq_pm_syscore_ops = {
189 .resume = irq_pm_syscore_resume,
190};
191
192static int __init irq_pm_init_ops(void)
193{
194 register_syscore_ops(&irq_pm_syscore_ops);
195 return 0;
196}
197
198device_initcall(irq_pm_init_ops);
199
200/**
201 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
202 *
203 * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously
204 * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag
205 * set as well as those with %IRQF_FORCE_RESUME.
206 */
207void resume_device_irqs(void)
208{
209 resume_irqs(false);
210}
211EXPORT_SYMBOL_GPL(resume_device_irqs);
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}