linux-stable/include/linux/cpu_pm.h
Thomas Gleixner 9c92ab6191 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282
Based on 1 normalized pattern(s):

  this software is licensed under the terms of the gnu general public
  license version 2 as published by the free software foundation and
  may be copied distributed and modified under those terms this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00

100 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2011 Google, Inc.
*
* Author:
* Colin Cross <ccross@android.com>
*/
#ifndef _LINUX_CPU_PM_H
#define _LINUX_CPU_PM_H
#include <linux/kernel.h>
#include <linux/notifier.h>
/*
* When a CPU goes to a low power state that turns off power to the CPU's
* power domain, the contents of some blocks (floating point coprocessors,
* interrupt controllers, caches, timers) in the same power domain can
* be lost. The cpm_pm notifiers provide a method for platform idle, suspend,
* and hotplug implementations to notify the drivers for these blocks that
* they may be reset.
*
* All cpu_pm notifications must be called with interrupts disabled.
*
* The notifications are split into two classes: CPU notifications and CPU
* cluster notifications.
*
* CPU notifications apply to a single CPU and must be called on the affected
* CPU. They are used to save per-cpu context for affected blocks.
*
* CPU cluster notifications apply to all CPUs in a single power domain. They
* are used to save any global context for affected blocks, and must be called
* after all the CPUs in the power domain have been notified of the low power
* state.
*/
/*
* Event codes passed as unsigned long val to notifier calls
*/
enum cpu_pm_event {
/* A single cpu is entering a low power state */
CPU_PM_ENTER,
/* A single cpu failed to enter a low power state */
CPU_PM_ENTER_FAILED,
/* A single cpu is exiting a low power state */
CPU_PM_EXIT,
/* A cpu power domain is entering a low power state */
CPU_CLUSTER_PM_ENTER,
/* A cpu power domain failed to enter a low power state */
CPU_CLUSTER_PM_ENTER_FAILED,
/* A cpu power domain is exiting a low power state */
CPU_CLUSTER_PM_EXIT,
};
#ifdef CONFIG_CPU_PM
int cpu_pm_register_notifier(struct notifier_block *nb);
int cpu_pm_unregister_notifier(struct notifier_block *nb);
int cpu_pm_enter(void);
int cpu_pm_exit(void);
int cpu_cluster_pm_enter(void);
int cpu_cluster_pm_exit(void);
#else
static inline int cpu_pm_register_notifier(struct notifier_block *nb)
{
return 0;
}
static inline int cpu_pm_unregister_notifier(struct notifier_block *nb)
{
return 0;
}
static inline int cpu_pm_enter(void)
{
return 0;
}
static inline int cpu_pm_exit(void)
{
return 0;
}
static inline int cpu_cluster_pm_enter(void)
{
return 0;
}
static inline int cpu_cluster_pm_exit(void)
{
return 0;
}
#endif
#endif