| Colin Cross | ab10023 | 2011-02-10 02:04:45 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 Google, Inc. |
| 3 | * |
| 4 | * Author: |
| 5 | * Colin Cross <ccross@android.com> |
| 6 | * |
| 7 | * This software is licensed under the terms of the GNU General Public |
| 8 | * License version 2, as published by the Free Software Foundation, and |
| 9 | * may be copied, distributed, and modified under those terms. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | */ |
| 17 | |
| 18 | #ifndef _LINUX_CPU_PM_H |
| 19 | #define _LINUX_CPU_PM_H |
| 20 | |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/notifier.h> |
| 23 | |
| 24 | /* |
| 25 | * When a CPU goes to a low power state that turns off power to the CPU's |
| 26 | * power domain, the contents of some blocks (floating point coprocessors, |
| 27 | * interrupt controllers, caches, timers) in the same power domain can |
| 28 | * be lost. The cpm_pm notifiers provide a method for platform idle, suspend, |
| 29 | * and hotplug implementations to notify the drivers for these blocks that |
| 30 | * they may be reset. |
| 31 | * |
| 32 | * All cpu_pm notifications must be called with interrupts disabled. |
| 33 | * |
| 34 | * The notifications are split into two classes: CPU notifications and CPU |
| 35 | * cluster notifications. |
| 36 | * |
| 37 | * CPU notifications apply to a single CPU and must be called on the affected |
| 38 | * CPU. They are used to save per-cpu context for affected blocks. |
| 39 | * |
| 40 | * CPU cluster notifications apply to all CPUs in a single power domain. They |
| 41 | * are used to save any global context for affected blocks, and must be called |
| 42 | * after all the CPUs in the power domain have been notified of the low power |
| 43 | * state. |
| 44 | */ |
| 45 | |
| 46 | /* |
| 47 | * Event codes passed as unsigned long val to notifier calls |
| 48 | */ |
| 49 | enum cpu_pm_event { |
| 50 | /* A single cpu is entering a low power state */ |
| 51 | CPU_PM_ENTER, |
| 52 | |
| 53 | /* A single cpu failed to enter a low power state */ |
| 54 | CPU_PM_ENTER_FAILED, |
| 55 | |
| 56 | /* A single cpu is exiting a low power state */ |
| 57 | CPU_PM_EXIT, |
| 58 | |
| 59 | /* A cpu power domain is entering a low power state */ |
| 60 | CPU_CLUSTER_PM_ENTER, |
| 61 | |
| 62 | /* A cpu power domain failed to enter a low power state */ |
| 63 | CPU_CLUSTER_PM_ENTER_FAILED, |
| 64 | |
| 65 | /* A cpu power domain is exiting a low power state */ |
| 66 | CPU_CLUSTER_PM_EXIT, |
| 67 | }; |
| 68 | |
| 69 | #ifdef CONFIG_CPU_PM |
| 70 | int cpu_pm_register_notifier(struct notifier_block *nb); |
| 71 | int cpu_pm_unregister_notifier(struct notifier_block *nb); |
| 72 | int cpu_pm_enter(void); |
| 73 | int cpu_pm_exit(void); |
| 74 | int cpu_cluster_pm_enter(void); |
| 75 | int cpu_cluster_pm_exit(void); |
| 76 | |
| 77 | #else |
| 78 | |
| 79 | static inline int cpu_pm_register_notifier(struct notifier_block *nb) |
| 80 | { |
| 81 | return 0; |
| 82 | } |
| 83 | |
| 84 | static inline int cpu_pm_unregister_notifier(struct notifier_block *nb) |
| 85 | { |
| 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | static inline int cpu_pm_enter(void) |
| 90 | { |
| 91 | return 0; |
| 92 | } |
| 93 | |
| 94 | static inline int cpu_pm_exit(void) |
| 95 | { |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | static inline int cpu_cluster_pm_enter(void) |
| 100 | { |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | static inline int cpu_cluster_pm_exit(void) |
| 105 | { |
| 106 | return 0; |
| 107 | } |
| 108 | #endif |
| 109 | #endif |