1 /*
2  * Copyright (C) 2018 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 "BatteryRechargingControl.h"
18 
19 namespace device {
20 namespace google {
21 namespace crosshatch {
22 namespace health {
23 
24 const std::string kChargerStatus = "sys/class/power_supply/battery/status";
25 
26 static const std::string kStatusIsFull = "Full";
27 static const std::string kStatusIsCharging = "Charging";
28 static constexpr int kTransitionTime = 15 * 60;  // Seconds
29 static constexpr int kFullSoc = 100;
30 
BatteryRechargingControl()31 BatteryRechargingControl::BatteryRechargingControl() {
32     state_ = INACTIVE;
33     recharge_soc_ = 0;
34 }
35 
mapSysfsString(const char * str,struct sysfsStringEnumMap map[])36 int BatteryRechargingControl::mapSysfsString(const char *str, struct sysfsStringEnumMap map[]) {
37     for (int i = 0; map[i].s; i++)
38         if (!strncmp(str, map[i].s, strlen(map[i].s)))
39             return map[i].val;
40 
41     return -1;
42 }
43 
getBatteryStatus(const char * status)44 int BatteryRechargingControl::getBatteryStatus(const char *status) {
45     int ret;
46     struct sysfsStringEnumMap batteryStatusMap[] = {
47         {"Unknown", android::BATTERY_STATUS_UNKNOWN},
48         {"Charging", android::BATTERY_STATUS_CHARGING},
49         {"Discharging", android::BATTERY_STATUS_DISCHARGING},
50         {"Not charging", android::BATTERY_STATUS_NOT_CHARGING},
51         {"Full", android::BATTERY_STATUS_FULL},
52         {NULL, 0},
53     };
54 
55     ret = mapSysfsString(status, batteryStatusMap);
56     if (ret < 0) {
57         LOG(ERROR) << "Unknown battery status: " << status;
58         ret = android::BATTERY_STATUS_UNKNOWN;
59     }
60 
61     return ret;
62 }
63 
getTime(void)64 int64_t BatteryRechargingControl::getTime(void) {
65     return nanoseconds_to_seconds(systemTime(SYSTEM_TIME_BOOTTIME));
66 }
67 
RemapSOC(int soc)68 int BatteryRechargingControl::RemapSOC(int soc) {
69     double diff_sec = getTime() - start_time_;
70     double ret_soc =
71         round(soc * (diff_sec / kTransitionTime) + kFullSoc * (1 - (diff_sec / kTransitionTime)));
72     LOG(INFO) << "RemapSOC: " << ret_soc;
73     return ret_soc;
74 }
75 
updateBatteryProperties(struct android::BatteryProperties * props)76 void BatteryRechargingControl::updateBatteryProperties(struct android::BatteryProperties *props) {
77     std::string charger_status;
78     double elapsed_time;
79     int cur_soc;
80 
81     if (!android::base::ReadFileToString(kChargerStatus, &charger_status)) {
82         LOG(ERROR) << "Cannot read the charger status";
83         return;
84     }
85 
86     charger_status = android::base::Trim(charger_status);
87     props->batteryStatus = getBatteryStatus(charger_status.c_str());
88 
89     if ((state_ == INACTIVE) && (props->batteryLevel < kFullSoc))
90         return;
91 
92     LOG(INFO) << "Entry state_: " << state_ << " charger_status: " << charger_status
93               << " batteryLevel: " << props->batteryLevel;
94     switch (state_) {
95         case INACTIVE:
96             state_ = WAIT_EOC;
97             recharge_soc_ = 0;
98         case WAIT_EOC:
99             if (charger_status == kStatusIsFull) {
100                 state_ = RECHARGING_CYCLE;
101                 props->batteryLevel = kFullSoc;
102             } else if (charger_status != kStatusIsCharging) {
103                 // charging stopped, assume no more power source
104                 start_time_ = getTime();
105                 state_ = NO_POWER_SOURCE;
106                 props->batteryLevel = RemapSOC(props->batteryLevel);
107             }
108             break;
109         case RECHARGING_CYCLE:
110             if (charger_status == kStatusIsFull) {
111                 recharge_soc_ = 0;
112                 props->batteryLevel = kFullSoc;
113                 break;
114             } else if (charger_status == kStatusIsCharging) {
115                 // Recharging cycle start.
116                 if (recharge_soc_ == 0) {
117                     recharge_soc_ = props->batteryLevel;
118                     props->batteryLevel = kFullSoc;
119                 } else {
120                     if (props->batteryLevel < recharge_soc_) {
121                         // overload condition
122                         start_time_ = getTime();
123                         state_ = OVER_LOADING;
124                         props->batteryLevel = RemapSOC(props->batteryLevel);
125                     } else {
126                         props->batteryLevel = kFullSoc;
127                     }
128                 }
129             } else {
130                 // charging stopped, assume no more power source
131                 start_time_ = getTime();
132                 state_ = NO_POWER_SOURCE;
133                 props->batteryLevel = RemapSOC(props->batteryLevel);
134             }
135             break;
136         case OVER_LOADING:
137         case NO_POWER_SOURCE:
138             cur_soc = props->batteryLevel;
139             elapsed_time = getTime() - start_time_;
140             if (elapsed_time > kTransitionTime) {
141                 LOG(INFO) << "Time is up, leave remap";
142                 state_ = INACTIVE;
143                 break;
144             } else {
145                 LOG(INFO) << "Diff time: " << elapsed_time;
146                 int battery_level = RemapSOC(props->batteryLevel);
147                 if ((battery_level == props->batteryLevel) && (battery_level != kFullSoc)) {
148                     state_ = INACTIVE;
149                     break;
150                 }
151                 props->batteryLevel = battery_level;
152             }
153             if (charger_status == kStatusIsCharging) {
154                 if ((props->batteryLevel == kFullSoc) && (cur_soc >= recharge_soc_)) {
155                     // When user plug in charger and the ret_soc is still 100%
156                     // Change condition to Recharging cycle to avoid the SOC
157                     // show lower than 100%. (Keep 100%)
158                     state_ = RECHARGING_CYCLE;
159                     recharge_soc_ = props->batteryLevel;
160                 }
161             }
162             break;
163         default:
164             state_ = WAIT_EOC;
165             break;
166     }
167     LOG(INFO) << "Exit state_: " << state_ << " batteryLevel: " << props->batteryLevel;
168 }
169 
170 }  // namespace health
171 }  // namespace crosshatch
172 }  // namespace google
173 }  // namespace device
174