LXR linux/drivers/base/syscore.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  syscore.c - Execution of system core operations.
   4 *
   5 *  Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
   6 */
   7
   8#include <linux/syscore_ops.h>
   9#include <linux/mutex.h>
  10#include <linux/module.h>
  11#include <linux/suspend.h>
  12#include <trace/events/power.h>
  13
  14static LIST_HEAD(syscore_ops_list);
  15static DEFINE_MUTEX(syscore_ops_lock);
  16
  17/**
  18 * register_syscore_ops - Register a set of system core operations.
  19 * @ops: System core operations to register.
  20 */
  21void register_syscore_ops(struct syscore_ops *ops)
  22{
  23        mutex_lock(&syscore_ops_lock);
  24        list_add_tail(&ops->node, &syscore_ops_list);
  25        mutex_unlock(&syscore_ops_lock);
  26}
  27EXPORT_SYMBOL_GPL(register_syscore_ops);
  28
  29/**
  30 * unregister_syscore_ops - Unregister a set of system core operations.
  31 * @ops: System core operations to unregister.
  32 */
  33void unregister_syscore_ops(struct syscore_ops *ops)
  34{
  35        mutex_lock(&syscore_ops_lock);
  36        list_del(&ops->node);
  37        mutex_unlock(&syscore_ops_lock);
  38}
  39EXPORT_SYMBOL_GPL(unregister_syscore_ops);
  40
  41#ifdef CONFIG_PM_SLEEP
  42/**
  43 * syscore_suspend - Execute all the registered system core suspend callbacks.
  44 *
  45 * This function is executed with one CPU on-line and disabled interrupts.
  46 */
  47int syscore_suspend(void)
  48{
  49        struct syscore_ops *ops;
  50        int ret = 0;
  51
  52        trace_suspend_resume(TPS("syscore_suspend"), 0, true);
  53        pr_debug("Checking wakeup interrupts\n");
  54
  55        /* Return error code if there are any wakeup interrupts pending. */
  56        if (pm_wakeup_pending())
  57                return -EBUSY;
  58
  59        WARN_ONCE(!irqs_disabled(),
  60                "Interrupts enabled before system core suspend.\n");
  61
  62        list_for_each_entry_reverse(ops, &syscore_ops_list, node)
  63                if (ops->suspend) {
  64                        if (initcall_debug)
  65                                pr_info("PM: Calling %pF\n", ops->suspend);
  66                        ret = ops->suspend();
  67                        if (ret)
  68                                goto err_out;
  69                        WARN_ONCE(!irqs_disabled(),
  70                                "Interrupts enabled after %pF\n", ops->suspend);
  71                }
  72
  73        trace_suspend_resume(TPS("syscore_suspend"), 0, false);
  74        return 0;
  75
  76 err_out:
  77        pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);
  78
  79        list_for_each_entry_continue(ops, &syscore_ops_list, node)
  80                if (ops->resume)
  81                        ops->resume();
  82
  83        return ret;
  84}
  85EXPORT_SYMBOL_GPL(syscore_suspend);
  86
  87/**
  88 * syscore_resume - Execute all the registered system core resume callbacks.
  89 *
  90 * This function is executed with one CPU on-line and disabled interrupts.
  91 */
  92void syscore_resume(void)
  93{
  94        struct syscore_ops *ops;
  95
  96        trace_suspend_resume(TPS("syscore_resume"), 0, true);
  97        WARN_ONCE(!irqs_disabled(),
  98                "Interrupts enabled before system core resume.\n");
  99
 100        list_for_each_entry(ops, &syscore_ops_list, node)
 101                if (ops->resume) {
 102                        if (initcall_debug)
 103                                pr_info("PM: Calling %pF\n", ops->resume);
 104                        ops->resume();
 105                        WARN_ONCE(!irqs_disabled(),
 106                                "Interrupts enabled after %pF\n", ops->resume);
 107                }
 108        trace_suspend_resume(TPS("syscore_resume"), 0, false);
 109}
 110EXPORT_SYMBOL_GPL(syscore_resume);
 111#endif /* CONFIG_PM_SLEEP */
 112
 113/**
 114 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
 115 */
 116void syscore_shutdown(void)
 117{
 118        struct syscore_ops *ops;
 119
 120        mutex_lock(&syscore_ops_lock);
 121
 122        list_for_each_entry_reverse(ops, &syscore_ops_list, node)
 123                if (ops->shutdown) {
 124                        if (initcall_debug)
 125                                pr_info("PM: Calling %pF\n", ops->shutdown);
 126                        ops->shutdown();
 127                }
 128
 129        mutex_unlock(&syscore_ops_lock);
 130}
 131