PM / Core: Introduce struct syscore_ops for core subsystems PM
[linux-2.6.git] / drivers / base / syscore.c
1 /*
2  *  syscore.c - Execution of system core operations.
3  *
4  *  Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5  *
6  *  This file is released under the GPLv2.
7  */
8
9 #include <linux/syscore_ops.h>
10 #include <linux/mutex.h>
11 #include <linux/module.h>
12
13 static LIST_HEAD(syscore_ops_list);
14 static DEFINE_MUTEX(syscore_ops_lock);
15
16 /**
17  * register_syscore_ops - Register a set of system core operations.
18  * @ops: System core operations to register.
19  */
20 void register_syscore_ops(struct syscore_ops *ops)
21 {
22         mutex_lock(&syscore_ops_lock);
23         list_add_tail(&ops->node, &syscore_ops_list);
24         mutex_unlock(&syscore_ops_lock);
25 }
26 EXPORT_SYMBOL_GPL(register_syscore_ops);
27
28 /**
29  * unregister_syscore_ops - Unregister a set of system core operations.
30  * @ops: System core operations to unregister.
31  */
32 void unregister_syscore_ops(struct syscore_ops *ops)
33 {
34         mutex_lock(&syscore_ops_lock);
35         list_del(&ops->node);
36         mutex_unlock(&syscore_ops_lock);
37 }
38 EXPORT_SYMBOL_GPL(unregister_syscore_ops);
39
40 #ifdef CONFIG_PM_SLEEP
41 /**
42  * syscore_suspend - Execute all the registered system core suspend callbacks.
43  *
44  * This function is executed with one CPU on-line and disabled interrupts.
45  */
46 int syscore_suspend(void)
47 {
48         struct syscore_ops *ops;
49         int ret = 0;
50
51         WARN_ONCE(!irqs_disabled(),
52                 "Interrupts enabled before system core suspend.\n");
53
54         list_for_each_entry_reverse(ops, &syscore_ops_list, node)
55                 if (ops->suspend) {
56                         if (initcall_debug)
57                                 pr_info("PM: Calling %pF\n", ops->suspend);
58                         ret = ops->suspend();
59                         if (ret)
60                                 goto err_out;
61                         WARN_ONCE(!irqs_disabled(),
62                                 "Interrupts enabled after %pF\n", ops->suspend);
63                 }
64
65         return 0;
66
67  err_out:
68         pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);
69
70         list_for_each_entry_continue(ops, &syscore_ops_list, node)
71                 if (ops->resume)
72                         ops->resume();
73
74         return ret;
75 }
76
77 /**
78  * syscore_resume - Execute all the registered system core resume callbacks.
79  *
80  * This function is executed with one CPU on-line and disabled interrupts.
81  */
82 void syscore_resume(void)
83 {
84         struct syscore_ops *ops;
85
86         WARN_ONCE(!irqs_disabled(),
87                 "Interrupts enabled before system core resume.\n");
88
89         list_for_each_entry(ops, &syscore_ops_list, node)
90                 if (ops->resume) {
91                         if (initcall_debug)
92                                 pr_info("PM: Calling %pF\n", ops->resume);
93                         ops->resume();
94                         WARN_ONCE(!irqs_disabled(),
95                                 "Interrupts enabled after %pF\n", ops->resume);
96                 }
97 }
98 #endif /* CONFIG_PM_SLEEP */
99
100 /**
101  * syscore_shutdown - Execute all the registered system core shutdown callbacks.
102  */
103 void syscore_shutdown(void)
104 {
105         struct syscore_ops *ops;
106
107         mutex_lock(&syscore_ops_lock);
108
109         list_for_each_entry_reverse(ops, &syscore_ops_list, node)
110                 if (ops->shutdown) {
111                         if (initcall_debug)
112                                 pr_info("PM: Calling %pF\n", ops->shutdown);
113                         ops->shutdown();
114                 }
115
116         mutex_unlock(&syscore_ops_lock);
117 }