Line data    Source code

       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             : 
      14             : static LIST_HEAD(syscore_ops_list);
      15             : static 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             :  */
      21           3 : void register_syscore_ops(struct syscore_ops *ops)
      22             : {
      23           3 :         mutex_lock(&syscore_ops_lock);
      24           3 :         list_add_tail(&ops->node, &syscore_ops_list);
      25           3 :         mutex_unlock(&syscore_ops_lock);
      26           3 : }
      27             : EXPORT_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             :  */
      33           0 : void unregister_syscore_ops(struct syscore_ops *ops)
      34             : {
      35           0 :         mutex_lock(&syscore_ops_lock);
      36           0 :         list_del(&ops->node);
      37           0 :         mutex_unlock(&syscore_ops_lock);
      38           0 : }
      39             : EXPORT_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             :  */
      47             : int syscore_suspend(void)
      48             : {
      49             :         struct syscore_ops *ops;
      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(ops, &syscore_ops_list, node)
      63             :                 if (ops->suspend) {
      64             :                         pm_pr_dbg("Calling %pS\n", ops->suspend);
      65             :                         ret = ops->suspend();
      66             :                         if (ret)
      67             :                                 goto err_out;
      68             :                         WARN_ONCE(!irqs_disabled(),
      69             :                                 "Interrupts enabled after %pS\n", ops->suspend);
      70             :                 }
      71             : 
      72             :         trace_suspend_resume(TPS("syscore_suspend"), 0, false);
      73             :         return 0;
      74             : 
      75             :  err_out:
      76             :         pr_err("PM: System core suspend callback %pS failed.\n", ops->suspend);
      77             : 
      78             :         list_for_each_entry_continue(ops, &syscore_ops_list, node)
      79             :                 if (ops->resume)
      80             :                         ops->resume();
      81             : 
      82             :         return ret;
      83             : }
      84             : EXPORT_SYMBOL_GPL(syscore_suspend);
      85             : 
      86             : /**
      87             :  * syscore_resume - Execute all the registered system core resume callbacks.
      88             :  *
      89             :  * This function is executed with one CPU on-line and disabled interrupts.
      90             :  */
      91             : void syscore_resume(void)
      92             : {
      93             :         struct syscore_ops *ops;
      94             : 
      95             :         trace_suspend_resume(TPS("syscore_resume"), 0, true);
      96             :         WARN_ONCE(!irqs_disabled(),
      97             :                 "Interrupts enabled before system core resume.\n");
      98             : 
      99             :         list_for_each_entry(ops, &syscore_ops_list, node)
     100             :                 if (ops->resume) {
     101             :                         pm_pr_dbg("Calling %pS\n", ops->resume);
     102             :                         ops->resume();
     103             :                         WARN_ONCE(!irqs_disabled(),
     104             :                                 "Interrupts enabled after %pS\n", ops->resume);
     105             :                 }
     106             :         trace_suspend_resume(TPS("syscore_resume"), 0, false);
     107             : }
     108             : EXPORT_SYMBOL_GPL(syscore_resume);
     109             : #endif /* CONFIG_PM_SLEEP */
     110             : 
     111             : /**
     112             :  * syscore_shutdown - Execute all the registered system core shutdown callbacks.
     113             :  */
     114           0 : void syscore_shutdown(void)
     115             : {
     116           0 :         struct syscore_ops *ops;
     117             : 
     118           0 :         mutex_lock(&syscore_ops_lock);
     119             : 
     120           0 :         list_for_each_entry_reverse(ops, &syscore_ops_list, node)
     121           0 :                 if (ops->shutdown) {
     122           0 :                         if (initcall_debug)
     123           0 :                                 pr_info("PM: Calling %pS\n", ops->shutdown);
     124           0 :                         ops->shutdown();
     125             :                 }
     126             : 
     127           0 :         mutex_unlock(&syscore_ops_lock);
     128           0 : }