LXR linux/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#include <linux/suspend.h>
  13#include <trace/events/power.h>
  14
  15static LIST_HEAD(syscore_ops_list);
  16static DEFINE_MUTEX(syscore_ops_lock);
  17
  18/**
  19 * register_syscore_ops - Register a set of system core operations.
  20 * @ops: System core operations to register.
  21 */
  22void register_syscore_ops(struct syscore_ops *ops)
  23{
  24        mutex_lock(&syscore_ops_lock);
  25        list_add_tail(&ops->node, &syscore_ops_list);
  26        mutex_unlock(&syscore_ops_lock);
  27}
  28EXPORT_SYMBOL_GPL(register_syscore_ops);
  29
  30/**
  31 * unregister_syscore_ops - Unregister a set of system core operations.
  32 * @ops: System core operations to unregister.
  33 */
  34void unregister_syscore_ops(struct syscore_ops *ops)
  35{
  36        mutex_lock(&syscore_ops_lock);
  37        list_del(&ops->node);
  38        mutex_unlock(&syscore_ops_lock);
  39}
  40EXPORT_SYMBOL_GPL(unregister_syscore_ops);
  41
  42#ifdef CONFIG_PM_SLEEP
  43/**
  44 * syscore_suspend - Execute all the registered system core suspend callbacks.
  45 *
  46 * This function is executed with one CPU on-line and disabled interrupts.
  47 */
  48int syscore_suspend(void)
  49{
  50        struct syscore_ops *ops;
  51        int ret = 0;
  52
  53        trace_suspend_resume(TPS("syscore_suspend"), 0, true);
  54        pr_debug("Checking wakeup interrupts\n");
  55
  56        /* Return error code if there are any wakeup interrupts pending. */
  57        if (pm_wakeup_pending())
  58                return -EBUSY;
  59
  60        WARN_ONCE(!irqs_disabled(),
  61                "Interrupts enabled before system core suspend.\n");
  62
  63        list_for_each_entry_reverse(ops, &syscore_ops_list, node)
  64                if (ops->suspend) {
  65                        if (initcall_debug)
  66                                pr_info("PM: Calling %pF\n", ops->suspend);
  67                        ret = ops->suspend();
  68                        if (ret)
  69                                goto err_out;
  70                        WARN_ONCE(!irqs_disabled(),
  71                                "Interrupts enabled after %pF\n", ops->suspend);
  72                }
  73
  74        trace_suspend_resume(TPS("syscore_suspend"), 0, false);
  75        return 0;
  76
  77 err_out:
  78        pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);
  79
  80        list_for_each_entry_continue(ops, &syscore_ops_list, node)
  81                if (ops->resume)
  82                        ops->resume();
  83
  84        return ret;
  85}
  86EXPORT_SYMBOL_GPL(syscore_suspend);
  87
  88/**
  89 * syscore_resume - Execute all the registered system core resume callbacks.
  90 *
  91 * This function is executed with one CPU on-line and disabled interrupts.
  92 */
  93void syscore_resume(void)
  94{
  95        struct syscore_ops *ops;
  96
  97        trace_suspend_resume(TPS("syscore_resume"), 0, true);
  98        WARN_ONCE(!irqs_disabled(),
  99                "Interrupts enabled before system core resume.\n");
 100
 101        list_for_each_entry(ops, &syscore_ops_list, node)
 102                if (ops->resume) {
 103                        if (initcall_debug)
 104                                pr_info("PM: Calling %pF\n", ops->resume);
 105                        ops->resume();
 106                        WARN_ONCE(!irqs_disabled(),
 107                                "Interrupts enabled after %pF\n", ops->resume);
 108                }
 109        trace_suspend_resume(TPS("syscore_resume"), 0, false);
 110}
 111EXPORT_SYMBOL_GPL(syscore_resume);
 112#endif /* CONFIG_PM_SLEEP */
 113
 114/**
 115 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
 116 */
 117void syscore_shutdown(void)
 118{
 119        struct syscore_ops *ops;
 120
 121        mutex_lock(&syscore_ops_lock);
 122
 123        list_for_each_entry_reverse(ops, &syscore_ops_list, node)
 124                if (ops->shutdown) {
 125                        if (initcall_debug)
 126                                pr_info("PM: Calling %pF\n", ops->shutdown);
 127                        ops->shutdown();
 128                }
 129
 130        mutex_unlock(&syscore_ops_lock);
 131}
 132