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 #define LOG_TAG "healthd-dragon"
18 #include <healthd/healthd.h>
19 #include <sys/stat.h>
20 #include <fcntl.h>
21 #include <cutils/klog.h>
22 #include <sys/types.h>
23
24 #define PSU_SYSFS_PATH "/sys/class/power_supply/bq27742-0"
25 #define PSU_SYSFS_MAX_CURRENT_PATH PSU_SYSFS_PATH "/current_max"
26 #define BATTERY_CRITICAL_LOW_CAP 10
27 #define BATTERY_CRITICAL_LOW_IMAX_MA 5000
28 #define BATTERY_MAX_IMAX_MA 9000
29
30 using namespace android;
31
read_sysfs(const char * path,char * buf,size_t size)32 static int read_sysfs(const char *path, char *buf, size_t size) {
33 char *cp = NULL;
34
35 int fd = open(path, O_RDONLY);
36 if (fd == -1) {
37 KLOG_ERROR(LOG_TAG, "Could not open '%s'\n", path);
38 return -1;
39 }
40
41 ssize_t count = TEMP_FAILURE_RETRY(read(fd, buf, size));
42 if (count > 0)
43 cp = (char *)memrchr(buf, '\n', count);
44
45 if (cp)
46 *cp = '\0';
47 else
48 buf[0] = '\0';
49
50 close(fd);
51 return count;
52 }
53
read_current_max_ma()54 static int read_current_max_ma() {
55 const int SIZE = 10;
56 char buf[SIZE];
57 if (read_sysfs(PSU_SYSFS_MAX_CURRENT_PATH, buf, SIZE) > 0)
58 return atoi(buf) / 1000;
59
60 return 0;
61 }
62
dragon_soc_adjust(struct BatteryProperties * props)63 static void dragon_soc_adjust(struct BatteryProperties *props)
64 {
65 int soc;
66 int current_max_ma;
67
68 soc = props->batteryLevel;
69 /*
70 * if not charging and State-Of-Charge (soc) is below
71 * BATTERY_CRITICAL_LOW_CAP shrink soc based on imax value
72 */
73 if ((soc < BATTERY_CRITICAL_LOW_CAP) &&
74 ((props->batteryStatus == BATTERY_STATUS_DISCHARGING) ||
75 (props->batteryStatus == BATTERY_STATUS_NOT_CHARGING) ||
76 (props->batteryStatus == BATTERY_STATUS_UNKNOWN))) {
77
78 current_max_ma = read_current_max_ma();
79 if (current_max_ma == 0)
80 /*
81 * Either it failed to read sysfs or its really zero. In either
82 * case lets just warn so logs will identify for further debug.
83 */
84 KLOG_WARNING(LOG_TAG, "imax=0\n");
85 else if (current_max_ma < BATTERY_CRITICAL_LOW_IMAX_MA)
86 /* force shutdown */
87 soc = 0;
88 else if (current_max_ma < BATTERY_MAX_IMAX_MA)
89 /* decrease soc towards zero */
90 soc = soc * current_max_ma / BATTERY_MAX_IMAX_MA;
91
92 KLOG_INFO(LOG_TAG, "imax=%d soc=%d\n", current_max_ma, soc);
93 }
94 props->batteryLevel = soc;
95 }
96
healthd_board_battery_update(struct BatteryProperties * props)97 int healthd_board_battery_update(struct BatteryProperties *props)
98 {
99
100 dragon_soc_adjust(props);
101
102 // return 0 to log periodic polled battery status to kernel log
103 return 0;
104 }
105
healthd_board_init(struct healthd_config * config)106 void healthd_board_init(struct healthd_config *config) {}
107