1 /*
2 * Copyright (c) 2017, The Linux Foundation. All rights reserved.
3 * Not a contribution
4 * Copyright (C) 2016 The Android Open Source Project
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 #include <ctype.h>
20 #include <errno.h>
21 #include <inttypes.h>
22 #include <stdlib.h>
23 #include <string.h>
24
25 #define LOG_TAG "ThermalHAL"
26 #include <utils/Log.h>
27
28 #include <hardware/hardware.h>
29 #include <hardware/thermal.h>
30
31 #define MAX_LENGTH 50
32
33 #define CPU_USAGE_FILE "/proc/stat"
34 #define CPU_ONLINE_FILE_FORMAT "/sys/devices/system/cpu/cpu%d/online"
35 #define CPU_PRESENT_FILE "/sys/devices/system/cpu/present"
36
get_cpu_label(unsigned int cpu_num)37 const char * __attribute__ ((weak)) get_cpu_label(unsigned int cpu_num) {
38 ALOGD("Entering %s",__func__);
39 static const char * cpu_label = "cpu";
40 return cpu_label;
41 }
42
get_num_cpus()43 size_t __attribute__ ((weak)) get_num_cpus() {
44 ALOGD("Entering %s",__func__);
45 FILE *file;
46 char *line = NULL;
47 size_t len = 0;
48 static size_t cpus = 0;
49 ssize_t read;
50
51 if(cpus) return cpus;
52
53 file = fopen(CPU_PRESENT_FILE, "r");
54 if (file == NULL) {
55 ALOGE("%s: failed to open: %s", __func__, strerror(errno));
56 return 0;
57 }
58
59 if ((read = getline(&line, &len, file)) != -1) {
60 if (strnlen(line, read) < 3 || strncmp(line, "0-", 2) != 0 || !isdigit(line[2]))
61 ALOGE("%s: Incorrect cpu present file format", __func__);
62 else
63 cpus = atoi(&line[2]) + 1;
64
65 free(line);
66 }
67 else
68 ALOGE("%s: failed to read cpu present file: %s", __func__, strerror(errno));
69
70 fclose(file);
71 return cpus;
72 }
73
get_temperatures(thermal_module_t * module,temperature_t * list,size_t size)74 ssize_t __attribute__ ((weak)) get_temperatures(thermal_module_t *module, temperature_t *list, size_t size) {
75 ALOGD("Entering %s",__func__);
76 return 0;
77 }
78
get_cpu_usages(thermal_module_t * module,cpu_usage_t * list)79 static ssize_t get_cpu_usages(thermal_module_t *module, cpu_usage_t *list) {
80 ALOGD("Entering %s",__func__);
81 int vals, cpu_num, online;
82 ssize_t read;
83 uint64_t user, nice, system, idle, active, total;
84 char *line = NULL;
85 size_t len = 0;
86 size_t size = 0;
87 size_t cpus = 0;
88 char file_name[MAX_LENGTH];
89 FILE *file;
90 FILE *cpu_file;
91
92 cpus = get_num_cpus();
93 if (!cpus)
94 return errno ? -errno : -EIO;
95
96 if (list == NULL)
97 return cpus;
98
99 file = fopen(CPU_USAGE_FILE, "r");
100 if (file == NULL) {
101 ALOGE("%s: failed to open: %s", __func__, strerror(errno));
102 return -errno;
103 }
104
105 while ((read = getline(&line, &len, file)) != -1) {
106 if (strnlen(line, read) < 4 || strncmp(line, "cpu", 3) != 0 || !isdigit(line[3])) {
107 free(line);
108 line = NULL;
109 len = 0;
110 continue;
111 }
112
113 vals = sscanf(line, "cpu%d %" SCNu64 " %" SCNu64 " %" SCNu64 " %" SCNu64, &cpu_num, &user,
114 &nice, &system, &idle);
115
116 free(line);
117 line = NULL;
118 len = 0;
119
120 if (vals != 5 || size == cpus) {
121 if (vals != 5) {
122 ALOGE("%s: failed to read CPU information from file: %s", __func__,
123 strerror(errno));
124 } else {
125 ALOGE("/proc/stat file has incorrect format.");
126 }
127 fclose(file);
128 return errno ? -errno : -EIO;
129 }
130
131 active = user + nice + system;
132 total = active + idle;
133
134 // Read online CPU information.
135 snprintf(file_name, MAX_LENGTH, CPU_ONLINE_FILE_FORMAT, cpu_num);
136 cpu_file = fopen(file_name, "r");
137 online = 0;
138 if (cpu_file == NULL) {
139 ALOGE("%s: failed to open file: %s (%s)", __func__, file_name, strerror(errno));
140 fclose(file);
141 return -errno;
142 }
143 if (1 != fscanf(cpu_file, "%d", &online)) {
144 ALOGE("%s: failed to read CPU online information from file: %s (%s)", __func__,
145 file_name, strerror(errno));
146 fclose(file);
147 fclose(cpu_file);
148 return errno ? -errno : -EIO;
149 }
150 fclose(cpu_file);
151
152 list[size] = (cpu_usage_t) {
153 .name = get_cpu_label(size),
154 .active = active,
155 .total = total,
156 .is_online = online
157 };
158
159 size++;
160 }
161 fclose(file);
162
163 if (size != cpus) {
164 ALOGE("/proc/stat file has incorrect format.");
165 return -EIO;
166 }
167
168 return cpus;
169 }
170
171 static struct hw_module_methods_t thermal_module_methods = {
172 .open = NULL,
173 };
174
175 thermal_module_t HAL_MODULE_INFO_SYM = {
176 .common = {
177 .tag = HARDWARE_MODULE_TAG,
178 .module_api_version = THERMAL_HARDWARE_MODULE_API_VERSION_0_1,
179 .hal_api_version = HARDWARE_HAL_API_VERSION,
180 .id = THERMAL_HARDWARE_MODULE_ID,
181 .name = "Thermal HAL",
182 .author = "The Android Open Source Project",
183 .methods = &thermal_module_methods,
184 },
185 .getTemperatures = get_temperatures,
186 .getCpuUsages = get_cpu_usages,
187 };
188