diff options
| -rw-r--r-- | driver/battery/max17055.c | 38 | ||||
| -rw-r--r-- | driver/battery/max17055.h | 2 |
2 files changed, 37 insertions, 3 deletions
diff --git a/driver/battery/max17055.c b/driver/battery/max17055.c index 05a6d7a5ae..99662284a6 100644 --- a/driver/battery/max17055.c +++ b/driver/battery/max17055.c @@ -18,6 +18,12 @@ #define CPRINTS(format, args...) cprints(CC_CHARGER, format, ## args) /* + * For max17055 to finish battery presence detection, this is the minimal time + * we have to wait since the last POR. LSB = 175ms. + */ +#define RELIABLE_BATT_DETECT_TIME 0x10 + +/* * Convert the register values to the units that match * smart battery protocol. */ @@ -219,12 +225,38 @@ int battery_status(int *status) enum battery_present battery_is_present(void) { - int status = 0; + int reg = 0; + static uint8_t batt_pres_sure; - if (max17055_read(REG_STATUS, &status)) + if (max17055_read(REG_STATUS, ®)) return BP_NOT_SURE; - if (status & STATUS_BST) + + if (reg & STATUS_BST) return BP_NO; + + if (!batt_pres_sure) { + /* + * The battery detection result is not reliable within + * ~2.8 secs since POR. + */ + if (!max17055_read(REG_TIMERH, ®)) { + /* + * The LSB of TIMERH reg is 3.2 hrs. If the reg has a + * nonzero value, battery detection must have been + * settled. + */ + if (reg) { + batt_pres_sure = 1; + return BP_YES; + } + if (!max17055_read(REG_TIMER, ®) && + ((uint32_t)reg > RELIABLE_BATT_DETECT_TIME)) { + batt_pres_sure = 1; + return BP_YES; + } + } + return BP_NOT_SURE; + } return BP_YES; } diff --git a/driver/battery/max17055.h b/driver/battery/max17055.h index be070e9896..5a3764d9de 100644 --- a/driver/battery/max17055.h +++ b/driver/battery/max17055.h @@ -37,12 +37,14 @@ #define REG_TEMPCO 0x39 #define REG_EMPTY_VOLTAGE 0x3a #define REG_FSTAT 0x3d +#define REG_TIMER 0x3e #define REG_QR_TABLE30 0x42 #define REG_DQACC 0x45 #define REG_DPACC 0x46 #define REG_STATUS2 0xb0 #define REG_HIBCFG 0xba #define REG_CONFIG2 0xbb +#define REG_TIMERH 0xbe #define REG_MODELCFG 0xdb /* Status reg (0x00) flags */ |