| 1 | /* |
| 2 | * Copyright (C) 2012 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ANDROID_INCLUDE_HARDWARE_POWER_H |
| 18 | #define ANDROID_INCLUDE_HARDWARE_POWER_H |
| 19 | |
| 20 | #include <stdint.h> |
| 21 | #include <sys/cdefs.h> |
| 22 | #include <sys/types.h> |
| 23 | |
| 24 | #include <hardware/hardware.h> |
| 25 | |
| 26 | __BEGIN_DECLS |
| 27 | |
| 28 | #define POWER_MODULE_API_VERSION_0_1 HARDWARE_MODULE_API_VERSION(0, 1) |
| 29 | #define POWER_MODULE_API_VERSION_0_2 HARDWARE_MODULE_API_VERSION(0, 2) |
| 30 | |
| 31 | |
| 32 | /** |
| 33 | * The id of this module |
| 34 | */ |
| 35 | #define POWER_HARDWARE_MODULE_ID "power" |
| 36 | |
| 37 | /* |
| 38 | * Power hint identifiers passed to (*powerHint) |
| 39 | */ |
| 40 | |
| 41 | typedef enum { |
| 42 | POWER_HINT_VSYNC = 0x00000001, |
| 43 | POWER_HINT_INTERACTION = 0x00000002, |
| 44 | POWER_HINT_VIDEO_ENCODE = 0x00000003, |
| 45 | POWER_HINT_CPU_BOOST = 0x00000004, |
| 46 | } power_hint_t; |
| 47 | |
| 48 | /** |
| 49 | * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM |
| 50 | * and the fields of this data structure must begin with hw_module_t |
| 51 | * followed by module specific information. |
| 52 | */ |
| 53 | typedef struct power_module { |
| 54 | struct hw_module_t common; |
| 55 | |
| 56 | /* |
| 57 | * (*init)() performs power management setup actions at runtime |
| 58 | * startup, such as to set default cpufreq parameters. This is |
| 59 | * called only by the Power HAL instance loaded by |
| 60 | * PowerManagerService. |
| 61 | */ |
| 62 | void (*init)(struct power_module *module); |
| 63 | |
| 64 | /* |
| 65 | * (*setInteractive)() performs power management actions upon the |
| 66 | * system entering interactive state (that is, the system is awake |
| 67 | * and ready for interaction, often with UI devices such as |
| 68 | * display and touchscreen enabled) or non-interactive state (the |
| 69 | * system appears asleep, display usually turned off). The |
| 70 | * non-interactive state is usually entered after a period of |
| 71 | * inactivity, in order to conserve battery power during |
| 72 | * such inactive periods. |
| 73 | * |
| 74 | * Typical actions are to turn on or off devices and adjust |
| 75 | * cpufreq parameters. This function may also call the |
| 76 | * appropriate interfaces to allow the kernel to suspend the |
| 77 | * system to low-power sleep state when entering non-interactive |
| 78 | * state, and to disallow low-power suspend when the system is in |
| 79 | * interactive state. When low-power suspend state is allowed, the |
| 80 | * kernel may suspend the system whenever no wakelocks are held. |
| 81 | * |
| 82 | * on is non-zero when the system is transitioning to an |
| 83 | * interactive / awake state, and zero when transitioning to a |
| 84 | * non-interactive / asleep state. |
| 85 | * |
| 86 | * This function is called to enter non-interactive state after |
| 87 | * turning off the screen (if present), and called to enter |
| 88 | * interactive state prior to turning on the screen. |
| 89 | */ |
| 90 | void (*setInteractive)(struct power_module *module, int on); |
| 91 | |
| 92 | /* |
| 93 | * (*powerHint) is called to pass hints on power requirements, which |
| 94 | * may result in adjustment of power/performance parameters of the |
| 95 | * cpufreq governor and other controls. The possible hints are: |
| 96 | * |
| 97 | * POWER_HINT_VSYNC |
| 98 | * |
| 99 | * Foreground app has started or stopped requesting a VSYNC pulse |
| 100 | * from SurfaceFlinger. If the app has started requesting VSYNC |
| 101 | * then CPU and GPU load is expected soon, and it may be appropriate |
| 102 | * to raise speeds of CPU, memory bus, etc. The data parameter is |
| 103 | * non-zero to indicate VSYNC pulse is now requested, or zero for |
| 104 | * VSYNC pulse no longer requested. |
| 105 | * |
| 106 | * POWER_HINT_INTERACTION |
| 107 | * |
| 108 | * User is interacting with the device, for example, touchscreen |
| 109 | * events are incoming. CPU and GPU load may be expected soon, |
| 110 | * and it may be appropriate to raise speeds of CPU, memory bus, |
| 111 | * etc. The data parameter is unused. |
| 112 | * |
| 113 | * POWER_HINT_VIDEO_ENCODE |
| 114 | * |
| 115 | * The user just started or stopped recording video. When encode |
| 116 | * begins, large writes to the SD card will be done and this may |
| 117 | * cause CPU frequency to increase. The data parameter is a string |
| 118 | * with semicolon-separated 'key:value' pairs. The most common key is |
| 119 | * 'state', which takes 0 or 1 as its value. For instance, To |
| 120 | * indicate that recording is beginning, the string "state:1" would |
| 121 | * need to be used. More keys can be provided depending on the data |
| 122 | * that is to be passed. |
| 123 | * |
| 124 | * POWER_HINT_CPU_BOOST |
| 125 | * |
| 126 | * An operation is happening where it would be ideal for the CPU to |
| 127 | * be boosted for a specific duration. The data parameter is an |
| 128 | * integer value of the boost duration in microseconds. |
| 129 | * |
| 130 | * A particular platform may choose to ignore any hint. |
| 131 | * |
| 132 | * availability: version 0.2 |
| 133 | * |
| 134 | */ |
| 135 | void (*powerHint)(struct power_module *module, power_hint_t hint, |
| 136 | void *data); |
| 137 | } power_module_t; |
| 138 | |
| 139 | |
| 140 | __END_DECLS |
| 141 | |
| 142 | #endif // ANDROID_INCLUDE_HARDWARE_POWER_H |