UPSTREAM: dt-bindings: rockchip-dw-mshc: add RK3368 dw-mshc description
[firefly-linux-kernel-4.4.55.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/suspend.h>
13 #include <linux/syscore_ops.h>
14
15 #include "internals.h"
16
17 bool 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  */
34 void 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  */
58 void 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
71 static 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  */
118 void 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 }
137 EXPORT_SYMBOL_GPL(suspend_device_irqs);
138
139 static 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++;
152 resume:
153         desc->istate &= ~IRQS_SUSPENDED;
154         __enable_irq(desc);
155 }
156
157 static 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  */
183 static void irq_pm_syscore_resume(void)
184 {
185         resume_irqs(true);
186 }
187
188 static struct syscore_ops irq_pm_syscore_ops = {
189         .resume         = irq_pm_syscore_resume,
190 };
191
192 static int __init irq_pm_init_ops(void)
193 {
194         register_syscore_ops(&irq_pm_syscore_ops);
195         return 0;
196 }
197
198 device_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  */
207 void resume_device_irqs(void)
208 {
209         resume_irqs(false);
210 }
211 EXPORT_SYMBOL_GPL(resume_device_irqs);