According to the datasheet the RTC needs a power rising slope of no more than 100µs/V to ensure a correct power-on reset. If the mainboard that hosts the RTC cannot guarantee this, a software reset sequence is needed in the case where the battery was drained completely.
As the rising slope of the power supply depends on so many parameters and is highly mainboard specific, refactor the initialization code to perform a software reset every time a power loss event is recognized by the RTC.
6e6261e rx6110sa: Add a software reset sequence in case of power loss
src/drivers/i2c/rx6110sa/rx6110sa.c | 87 +++++++++++++++++++++++--------------
src/drivers/i2c/rx6110sa/rx6110sa.h | 10 +++--
2 files changed, 61 insertions(+), 36 deletions(-)