Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2020 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 | /** |
| 18 | * @addtogroup Thermal |
| 19 | * @{ |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file thermal.h |
| 24 | */ |
| 25 | |
| 26 | #ifndef _ANDROID_THERMAL_H |
| 27 | #define _ANDROID_THERMAL_H |
| 28 | |
| 29 | #include <sys/cdefs.h> |
| 30 | |
| 31 | /****************************************************************** |
| 32 | * |
| 33 | * IMPORTANT NOTICE: |
| 34 | * |
| 35 | * This file is part of Android's set of stable system headers |
| 36 | * exposed by the Android NDK (Native Development Kit). |
| 37 | * |
| 38 | * Third-party source AND binary code relies on the definitions |
| 39 | * here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES. |
| 40 | * |
| 41 | * - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES) |
| 42 | * - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS |
| 43 | * - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY |
| 44 | * - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES |
| 45 | */ |
| 46 | |
| 47 | /* |
| 48 | * Structures and functions to access thermal status and register/unregister |
| 49 | * thermal status listener in native code. |
| 50 | */ |
| 51 | |
| 52 | #include <stdint.h> |
| 53 | #include <sys/types.h> |
| 54 | |
| 55 | #if !defined(__INTRODUCED_IN) |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 56 | #define __INTRODUCED_IN(__api_level) /* nothing */ |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 57 | #endif |
| 58 | |
| 59 | #ifdef __cplusplus |
| 60 | extern "C" { |
| 61 | #endif |
| 62 | |
gfan | 5d5faa4 | 2021-04-12 15:14:29 -0700 | [diff] [blame] | 63 | /** |
| 64 | * Thermal status used in function {@link AThermal_getCurrentThermalStatus} and |
| 65 | * {@link AThermal_StatusCallback}. |
| 66 | */ |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 67 | enum AThermalStatus { |
| 68 | /** Error in thermal status. */ |
| 69 | ATHERMAL_STATUS_ERROR = -1, |
| 70 | /** Not under throttling. */ |
| 71 | ATHERMAL_STATUS_NONE = 0, |
| 72 | /** Light throttling where UX is not impacted. */ |
| 73 | ATHERMAL_STATUS_LIGHT = 1, |
| 74 | /** Moderate throttling where UX is not largely impacted. */ |
| 75 | ATHERMAL_STATUS_MODERATE = 2, |
| 76 | /** Severe throttling where UX is largely impacted. */ |
| 77 | ATHERMAL_STATUS_SEVERE = 3, |
| 78 | /** Platform has done everything to reduce power. */ |
| 79 | ATHERMAL_STATUS_CRITICAL = 4, |
| 80 | /** |
| 81 | * Key components in platform are shutting down due to thermal condition. |
| 82 | * Device functionalities will be limited. |
| 83 | */ |
| 84 | ATHERMAL_STATUS_EMERGENCY = 5, |
| 85 | /** Need shutdown immediately. */ |
| 86 | ATHERMAL_STATUS_SHUTDOWN = 6, |
| 87 | }; |
| 88 | |
| 89 | /** |
| 90 | * An opaque type representing a handle to a thermal manager. |
| 91 | * An instance of thermal manager must be acquired prior to |
| 92 | * using thermal status APIs and must be released after use. |
| 93 | * |
| 94 | * <p>To use:<ul> |
| 95 | * <li>Create a new thermal manager instance by calling the |
| 96 | * {@link AThermal_acquireManager} function.</li> |
| 97 | * <li>Get current thermal status with |
| 98 | * {@link AThermal_getCurrentThermalStatus}.</li> |
| 99 | * <li>Register a thermal status listener with |
| 100 | * {@link AThermal_registerThermalStatusListener}.</li> |
| 101 | * <li>Unregister a thermal status listener with |
| 102 | * {@link AThermal_unregisterThermalStatusListener}.</li> |
| 103 | * <li>Release the thermal manager instance with |
| 104 | * {@link AThermal_releaseManager}.</li></ul></p> |
| 105 | * |
| 106 | */ |
| 107 | typedef struct AThermalManager AThermalManager; |
| 108 | |
| 109 | /** |
| 110 | * Prototype of the function that is called when thermal status changes. |
| 111 | * It's passed the updated thermal status as parameter, as well as the |
| 112 | * pointer provided by the client that registered a callback. |
| 113 | */ |
Xiang Wang | e6c65b3 | 2023-10-09 13:39:37 -0700 | [diff] [blame] | 114 | typedef void (*AThermal_StatusCallback)(void* data, AThermalStatus status); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 115 | |
| 116 | /** |
| 117 | * Acquire an instance of the thermal manager. This must be freed using |
| 118 | * {@link AThermal_releaseManager}. |
| 119 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 120 | * Available since API level 30. |
| 121 | * |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 122 | * @return manager instance on success, nullptr on failure. |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 123 | */ |
| 124 | AThermalManager* AThermal_acquireManager() __INTRODUCED_IN(30); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 125 | |
| 126 | /** |
| 127 | * Release the thermal manager pointer acquired via |
| 128 | * {@link AThermal_acquireManager}. |
| 129 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 130 | * Available since API level 30. |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 131 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 132 | * @param manager The manager to be released. |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 133 | */ |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 134 | void AThermal_releaseManager(AThermalManager *manager) __INTRODUCED_IN(30); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 135 | |
| 136 | /** |
| 137 | * Gets the current thermal status. |
| 138 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 139 | * Available since API level 30. |
| 140 | * |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 141 | * @param manager The manager instance to use to query the thermal status. |
| 142 | * Acquired via {@link AThermal_acquireManager}. |
| 143 | * |
| 144 | * @return current thermal status, ATHERMAL_STATUS_ERROR on failure. |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 145 | */ |
| 146 | AThermalStatus AThermal_getCurrentThermalStatus(AThermalManager *manager) __INTRODUCED_IN(30); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 147 | |
| 148 | /** |
| 149 | * Register the thermal status listener for thermal status change. |
| 150 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 151 | * Available since API level 30. |
| 152 | * |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 153 | * @param manager The manager instance to use to register. |
| 154 | * Acquired via {@link AThermal_acquireManager}. |
| 155 | * @param callback The callback function to be called when thermal status updated. |
| 156 | * @param data The data pointer to be passed when callback is called. |
| 157 | * |
| 158 | * @return 0 on success |
| 159 | * EINVAL if the listener and data pointer were previously added and not removed. |
| 160 | * EPERM if the required permission is not held. |
| 161 | * EPIPE if communication with the system service has failed. |
| 162 | */ |
| 163 | int AThermal_registerThermalStatusListener(AThermalManager *manager, |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 164 | AThermal_StatusCallback callback, void *data) __INTRODUCED_IN(30); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 165 | |
| 166 | /** |
| 167 | * Unregister the thermal status listener previously resgistered. |
| 168 | * |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 169 | * Available since API level 30. |
| 170 | * |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 171 | * @param manager The manager instance to use to unregister. |
| 172 | * Acquired via {@link AThermal_acquireManager}. |
| 173 | * @param callback The callback function to be called when thermal status updated. |
| 174 | * @param data The data pointer to be passed when callback is called. |
| 175 | * |
| 176 | * @return 0 on success |
| 177 | * EINVAL if the listener and data pointer were not previously added. |
| 178 | * EPERM if the required permission is not held. |
| 179 | * EPIPE if communication with the system service has failed. |
| 180 | */ |
| 181 | int AThermal_unregisterThermalStatusListener(AThermalManager *manager, |
Elliott Hughes | 7be0e2d | 2020-06-02 13:05:04 -0700 | [diff] [blame] | 182 | AThermal_StatusCallback callback, void *data) __INTRODUCED_IN(30); |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 183 | |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 184 | /** |
| 185 | * Provides an estimate of how much thermal headroom the device currently has before |
| 186 | * hitting severe throttling. |
| 187 | * |
| 188 | * Note that this only attempts to track the headroom of slow-moving sensors, such as |
| 189 | * the skin temperature sensor. This means that there is no benefit to calling this function |
| 190 | * more frequently than about once per second, and attempted to call significantly |
Elliott Hughes | d4b452c | 2023-09-15 22:52:03 +0000 | [diff] [blame] | 191 | * more frequently may result in the function returning `NaN`. |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 192 | * |
| 193 | * In addition, in order to be able to provide an accurate forecast, the system does |
| 194 | * not attempt to forecast until it has multiple temperature samples from which to |
| 195 | * extrapolate. This should only take a few seconds from the time of the first call, |
| 196 | * but during this time, no forecasting will occur, and the current headroom will be |
Elliott Hughes | d4b452c | 2023-09-15 22:52:03 +0000 | [diff] [blame] | 197 | * returned regardless of the value of `forecastSeconds`. |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 198 | * |
| 199 | * The value returned is a non-negative float that represents how much of the thermal envelope |
| 200 | * is in use (or is forecasted to be in use). A value of 1.0 indicates that the device is |
gfan | 5d5faa4 | 2021-04-12 15:14:29 -0700 | [diff] [blame] | 201 | * (or will be) throttled at {@link #ATHERMAL_STATUS_SEVERE}. Such throttling can affect the |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 202 | * CPU, GPU, and other subsystems. Values may exceed 1.0, but there is no implied mapping |
| 203 | * to specific thermal levels beyond that point. This means that values greater than 1.0 |
gfan | 5d5faa4 | 2021-04-12 15:14:29 -0700 | [diff] [blame] | 204 | * may correspond to {@link #ATHERMAL_STATUS_SEVERE}, but may also represent heavier throttling. |
Chris Forbes | 56e925a | 2020-09-15 09:34:59 -0700 | [diff] [blame] | 205 | * |
| 206 | * A value of 0.0 corresponds to a fixed distance from 1.0, but does not correspond to any |
| 207 | * particular thermal status or temperature. Values on (0.0, 1.0] may be expected to scale |
| 208 | * linearly with temperature, though temperature changes over time are typically not linear. |
| 209 | * Negative values will be clamped to 0.0 before returning. |
| 210 | * |
| 211 | * Available since API level 31. |
| 212 | * |
| 213 | * @param manager The manager instance to use. |
| 214 | * Acquired via {@link AThermal_acquireManager}. |
| 215 | * @param forecastSeconds how many seconds into the future to forecast. Given that device |
| 216 | * conditions may change at any time, forecasts from further in the |
| 217 | * future will likely be less accurate than forecasts in the near future. |
| 218 | * @return a value greater than equal to 0.0, where 1.0 indicates the SEVERE throttling threshold, |
| 219 | * as described above. Returns NaN if the device does not support this functionality or |
| 220 | * if this function is called significantly faster than once per second. |
| 221 | */ |
| 222 | float AThermal_getThermalHeadroom(AThermalManager *manager, |
| 223 | int forecastSeconds) __INTRODUCED_IN(31); |
| 224 | |
Xiang Wang | e6c65b3 | 2023-10-09 13:39:37 -0700 | [diff] [blame] | 225 | /** |
| 226 | * This struct defines an instance of headroom threshold value and its status. |
| 227 | * <p> |
| 228 | * The value should be monotonically non-decreasing as the thermal status increases. |
| 229 | * For {@link ATHERMAL_STATUS_SEVERE}, its headroom threshold is guaranteed to |
| 230 | * be 1.0f. For status below severe status, the value should be lower or equal |
| 231 | * to 1.0f, and for status above severe, the value should be larger or equal to 1.0f. |
| 232 | * <p> |
| 233 | * Also see {@link AThermal_getThermalHeadroom} for explanation on headroom, and |
| 234 | * {@link AThermal_getThermalHeadroomThresholds} for how to use this. |
| 235 | */ |
| 236 | struct AThermalHeadroomThreshold { |
| 237 | float headroom; |
| 238 | AThermalStatus thermalStatus; |
| 239 | }; |
| 240 | |
| 241 | /** |
| 242 | * Gets the thermal headroom thresholds for all available thermal status. |
| 243 | * |
| 244 | * A thermal status will only exist in output if the device manufacturer has the |
| 245 | * corresponding threshold defined for at least one of its slow-moving skin temperature |
| 246 | * sensors. If it's set, one should also expect to get it from |
| 247 | * {@link #AThermal_getCurrentThermalStatus} or {@link AThermal_StatusCallback}. |
| 248 | * <p> |
| 249 | * The headroom threshold is used to interpret the possible thermal throttling status based on |
| 250 | * the headroom prediction. For example, if the headroom threshold for |
| 251 | * {@link ATHERMAL_STATUS_LIGHT} is 0.7, and a headroom prediction in 10s returns 0.75 |
| 252 | * (or {@code AThermal_getThermalHeadroom(10)=0.75}), one can expect that in 10 seconds the system |
| 253 | * could be in lightly throttled state if the workload remains the same. The app can consider |
| 254 | * taking actions according to the nearest throttling status the difference between the headroom and |
| 255 | * the threshold. |
| 256 | * <p> |
| 257 | * For new devices it's guaranteed to have a single sensor, but for older devices with multiple |
| 258 | * sensors reporting different threshold values, the minimum threshold is taken to be conservative |
| 259 | * on predictions. Thus, when reading real-time headroom, it's not guaranteed that a real-time value |
| 260 | * of 0.75 (or {@code AThermal_getThermalHeadroom(0)}=0.75) exceeding the threshold of 0.7 above |
| 261 | * will always come with lightly throttled state |
| 262 | * (or {@code AThermal_getCurrentThermalStatus()=ATHERMAL_STATUS_LIGHT}) but it can be lower |
| 263 | * (or {@code AThermal_getCurrentThermalStatus()=ATHERMAL_STATUS_NONE}). |
| 264 | * While it's always guaranteed that the device won't be throttled heavier than the unmet |
| 265 | * threshold's state, so a real-time headroom of 0.75 will never come with |
| 266 | * {@link #ATHERMAL_STATUS_MODERATE} but always lower, and 0.65 will never come with |
| 267 | * {@link ATHERMAL_STATUS_LIGHT} but {@link #ATHERMAL_STATUS_NONE}. |
| 268 | * <p> |
| 269 | * The returned list of thresholds is cached on first successful query and owned by the thermal |
| 270 | * manager, which will not change between calls to this function. The caller should only need to |
| 271 | * free the manager with {@link AThermal_releaseManager}. |
| 272 | * |
| 273 | * @param manager The manager instance to use. |
| 274 | * Acquired via {@link AThermal_acquireManager}. |
| 275 | * @param outThresholds non-null output pointer to null AThermalHeadroomThreshold pointer, which |
| 276 | * will be set to the cached array of thresholds if thermal thresholds are supported |
| 277 | * by the system or device, otherwise nullptr or unmodified. |
| 278 | * @param size non-null output pointer whose value will be set to the size of the threshold array |
| 279 | * or 0 if it's not supported. |
| 280 | * @return 0 on success |
| 281 | * EINVAL if outThresholds or size_t is nullptr, or *outThresholds is not nullptr. |
| 282 | * EPIPE if communication with the system service has failed. |
| 283 | * ENOSYS if the feature is disabled by the current system. |
| 284 | */ |
| 285 | int AThermal_getThermalHeadroomThresholds(AThermalManager* manager, |
| 286 | const AThermalHeadroomThreshold ** outThresholds, |
| 287 | size_t* size) __INTRODUCED_IN(35); |
| 288 | |
Chris Ye | 1a5a888 | 2020-01-15 10:51:47 -0800 | [diff] [blame] | 289 | #ifdef __cplusplus |
| 290 | } |
| 291 | #endif |
| 292 | |
| 293 | #endif // _ANDROID_THERMAL_H |
| 294 | |
| 295 | /** @} */ |