1 /* 2 * Copyright (C) 2016 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 #include <errno.h> 18 #include <ctype.h> 19 #include <dirent.h> 20 #include <inttypes.h> 21 #include <stdlib.h> 22 #include <string.h> 23 24 #define LOG_TAG "ThermalHAL" 25 #include <utils/Log.h> 26 27 #include <hardware/hardware.h> 28 #include <hardware/thermal.h> 29 30 #define CPU_LABEL "CPU" 31 #define MAX_LENGTH 50 32 33 #define CPU_USAGE_FILE "/proc/stat" 34 #define TEMPERATURE_DIR "/sys/class/thermal" 35 #define THERMAL_DIR "thermal_zone" 36 #define CPU_ONLINE_FILE_FORMAT "/sys/devices/system/cpu/cpu%d/online" 37 #define UNKNOWN_LABEL "UNKNOWN" 38 39 static ssize_t get_temperatures(thermal_module_t *module, temperature_t *list, size_t size) { 40 char file_name[MAX_LENGTH]; 41 FILE *file; 42 float temp; 43 size_t idx = 0; 44 DIR *dir; 45 struct dirent *de; 46 47 /** Read all available temperatures from 48 * /sys/class/thermal/thermal_zone[0-9]+/temp files. 49 * Don't guarantee that all temperatures are in Celsius. */ 50 dir = opendir(TEMPERATURE_DIR); 51 if (dir == 0) { 52 ALOGE("%s: failed to open directory %s: %s", __func__, TEMPERATURE_DIR, strerror(-errno)); 53 return -errno; 54 } 55 56 while ((de = readdir(dir))) { 57 if (!strncmp(de->d_name, THERMAL_DIR, strlen(THERMAL_DIR))) { 58 snprintf(file_name, MAX_LENGTH, "%s/%s/temp", TEMPERATURE_DIR, de->d_name); 59 file = fopen(file_name, "r"); 60 if (file == NULL) { 61 continue; 62 } 63 if (1 != fscanf(file, "%f", &temp)) { 64 fclose(file); 65 continue; 66 } 67 68 if (list != NULL && idx < size) { 69 list[idx] = (temperature_t) { 70 .name = UNKNOWN_LABEL, 71 .type = DEVICE_TEMPERATURE_UNKNOWN, 72 .current_value = temp, 73 .throttling_threshold = UNKNOWN_TEMPERATURE, 74 .shutdown_threshold = UNKNOWN_TEMPERATURE, 75 .vr_throttling_threshold = UNKNOWN_TEMPERATURE, 76 }; 77 } 78 fclose(file); 79 idx++; 80 } 81 } 82 closedir(dir); 83 return idx; 84 } 85 86 static ssize_t get_cpu_usages(thermal_module_t *module, cpu_usage_t *list) { 87 int vals, cpu_num, online; 88 ssize_t read; 89 uint64_t user, nice, system, idle, active, total; 90 char *line = NULL; 91 size_t len = 0; 92 size_t size = 0; 93 char file_name[MAX_LENGTH]; 94 FILE *cpu_file; 95 FILE *file = fopen(CPU_USAGE_FILE, "r"); 96 97 if (file == NULL) { 98 ALOGE("%s: failed to open: %s", __func__, strerror(errno)); 99 return -errno; 100 } 101 102 while ((read = getline(&line, &len, file)) != -1) { 103 // Skip non "cpu[0-9]" lines. 104 if (strnlen(line, read) < 4 || strncmp(line, "cpu", 3) != 0 || !isdigit(line[3])) { 105 free(line); 106 line = NULL; 107 len = 0; 108 continue; 109 } 110 vals = sscanf(line, "cpu%d %" SCNu64 " %" SCNu64 " %" SCNu64 " %" SCNu64, &cpu_num, &user, 111 &nice, &system, &idle); 112 113 free(line); 114 line = NULL; 115 len = 0; 116 117 if (vals != 5) { 118 ALOGE("%s: failed to read CPU information from file: %s", __func__, strerror(errno)); 119 fclose(file); 120 return errno ? -errno : -EIO; 121 } 122 123 active = user + nice + system; 124 total = active + idle; 125 126 // Read online CPU information. 127 snprintf(file_name, MAX_LENGTH, CPU_ONLINE_FILE_FORMAT, cpu_num); 128 cpu_file = fopen(file_name, "r"); 129 online = 0; 130 if (cpu_file == NULL) { 131 ALOGE("%s: failed to open file: %s (%s)", __func__, file_name, strerror(errno)); 132 // /sys/devices/system/cpu/cpu0/online is missing on some systems, because cpu0 can't 133 // be offline. 134 online = cpu_num == 0; 135 } else if (1 != fscanf(cpu_file, "%d", &online)) { 136 ALOGE("%s: failed to read CPU online information from file: %s (%s)", __func__, 137 file_name, strerror(errno)); 138 fclose(file); 139 fclose(cpu_file); 140 return errno ? -errno : -EIO; 141 } else { 142 fclose(cpu_file); 143 } 144 145 if (list != NULL) { 146 list[size] = (cpu_usage_t) { 147 .name = CPU_LABEL, 148 .active = active, 149 .total = total, 150 .is_online = online 151 }; 152 } 153 154 size++; 155 } 156 157 fclose(file); 158 return size; 159 } 160 161 static ssize_t get_cooling_devices(thermal_module_t *module, cooling_device_t *list, size_t size) { 162 return 0; 163 } 164 165 static struct hw_module_methods_t thermal_module_methods = { 166 .open = NULL, 167 }; 168 169 thermal_module_t HAL_MODULE_INFO_SYM = { 170 .common = { 171 .tag = HARDWARE_MODULE_TAG, 172 .module_api_version = THERMAL_HARDWARE_MODULE_API_VERSION_0_1, 173 .hal_api_version = HARDWARE_HAL_API_VERSION, 174 .id = THERMAL_HARDWARE_MODULE_ID, 175 .name = "Default Thermal HAL", 176 .author = "The Android Open Source Project", 177 .methods = &thermal_module_methods, 178 }, 179 180 .getTemperatures = get_temperatures, 181 .getCpuUsages = get_cpu_usages, 182 .getCoolingDevices = get_cooling_devices, 183 }; 184