1 /* 2 * Copyright (C) 2021 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 SRC_TRACED_PROBES_POWER_LINUX_POWER_SYSFS_DATA_SOURCE_H_ 18 #define SRC_TRACED_PROBES_POWER_LINUX_POWER_SYSFS_DATA_SOURCE_H_ 19 20 #include <optional> 21 22 #include "perfetto/ext/base/weak_ptr.h" 23 #include "perfetto/tracing/core/data_source_config.h" 24 #include "src/traced/probes/probes_data_source.h" 25 26 namespace perfetto { 27 class BatteryInfo; 28 class TraceWriter; 29 30 namespace base { 31 class TaskRunner; 32 } 33 34 class LinuxPowerSysfsDataSource : public ProbesDataSource { 35 public: 36 class BatteryInfo { 37 public: 38 explicit BatteryInfo( 39 const char* power_supply_dir_path = "/sys/class/power_supply"); 40 ~BatteryInfo(); 41 42 // The current coloumb counter value in µAh. 43 std::optional<int64_t> GetChargeCounterUah(size_t battery_idx); 44 45 // The current energy counter in µWh. 46 std::optional<int64_t> GetEnergyCounterUah(size_t battery_idx); 47 48 // The voltage in µV. 49 std::optional<int64_t> GetVoltageUv(size_t battery_idx); 50 51 // The battery capacity in percent. 52 std::optional<int64_t> GetCapacityPercent(size_t battery_idx); 53 54 // The current reading of the battery in µA. 55 std::optional<int64_t> GetCurrentNowUa(size_t battery_idx); 56 57 // The smoothed current reading of the battery in µA. 58 std::optional<int64_t> GetAverageCurrentUa(size_t battery_idx); 59 60 // Name of the battery. 61 std::string GetBatteryName(size_t battery_idx); 62 63 size_t num_batteries() const; 64 65 private: 66 std::string power_supply_dir_path_; 67 // The subdirectories that contain info of a battery power supply, e.g. 68 // BAT0. 69 std::vector<std::string> sysfs_battery_subdirs_; 70 }; 71 static const ProbesDataSource::Descriptor descriptor; 72 73 LinuxPowerSysfsDataSource(DataSourceConfig, 74 base::TaskRunner*, 75 TracingSessionID, 76 std::unique_ptr<TraceWriter> writer); 77 78 ~LinuxPowerSysfsDataSource() override; 79 80 base::WeakPtr<LinuxPowerSysfsDataSource> GetWeakPtr() const; 81 82 // ProbesDataSource implementation. 83 void Start() override; 84 void Flush(FlushRequestID, std::function<void()> callback) override; 85 // Use the default ClearIncrementalState() implementation: this data source 86 // doesn't have any incremental state. 87 88 private: 89 void Tick(); 90 void WriteBatteryCounters(); 91 92 uint32_t poll_interval_ms_ = 0; 93 94 base::TaskRunner* const task_runner_; 95 std::unique_ptr<TraceWriter> writer_; 96 std::unique_ptr<BatteryInfo> battery_info_; 97 base::WeakPtrFactory<LinuxPowerSysfsDataSource> weak_factory_; // Keep last. 98 }; 99 100 } // namespace perfetto 101 102 #endif // SRC_TRACED_PROBES_POWER_LINUX_POWER_SYSFS_DATA_SOURCE_H_ 103