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_list);
 15static DEFINE_MUTEX(syscore_lock);
 16
 17/**
 18 * register_syscore - Register a set of system core operations.
 19 * @syscore: System core operations to register.
 20 */
 21void register_syscore(struct syscore *syscore)
 22{
 23	mutex_lock(&syscore_lock);
 24	list_add_tail(&syscore->node, &syscore_list);
 25	mutex_unlock(&syscore_lock);
 26}
 27EXPORT_SYMBOL_GPL(register_syscore);
 28
 29/**
 30 * unregister_syscore - Unregister a set of system core operations.
 31 * @syscore: System core operations to unregister.
 32 */
 33void unregister_syscore(struct syscore *syscore)
 34{
 35	mutex_lock(&syscore_lock);
 36	list_del(&syscore->node);
 37	mutex_unlock(&syscore_lock);
 38}
 39EXPORT_SYMBOL_GPL(unregister_syscore);
 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 *syscore;
 50	int ret = 0;
 51
 52	trace_suspend_resume(TPS("syscore_suspend"), 0, true);
 53	pm_pr_dbg("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(syscore, &syscore_list, node)
 63		if (syscore->ops->suspend) {
 64			pm_pr_dbg("Calling %pS\n", syscore->ops->suspend);
 65			ret = syscore->ops->suspend(syscore->data);
 66			if (ret)
 67				goto err_out;
 68			WARN_ONCE(!irqs_disabled(),
 69				"Interrupts enabled after %pS\n",
 70				syscore->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 %pS failed.\n",
 78	       syscore->ops->suspend);
 79
 80	list_for_each_entry_continue(syscore, &syscore_list, node)
 81		if (syscore->ops->resume)
 82			syscore->ops->resume(syscore->data);
 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 *syscore;
 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(syscore, &syscore_list, node)
102		if (syscore->ops->resume) {
103			pm_pr_dbg("Calling %pS\n", syscore->ops->resume);
104			syscore->ops->resume(syscore->data);
105			WARN_ONCE(!irqs_disabled(),
106				"Interrupts enabled after %pS\n",
107				syscore->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 *syscore;
120
121	mutex_lock(&syscore_lock);
122
123	list_for_each_entry_reverse(syscore, &syscore_list, node)
124		if (syscore->ops->shutdown) {
125			if (initcall_debug)
126				pr_info("PM: Calling %pS\n",
127					syscore->ops->shutdown);
128			syscore->ops->shutdown(syscore->data);
129		}
130
131	mutex_unlock(&syscore_lock);
132}