Nokia RX-51 (N900) battery driver

modulename: rx51_battery.ko

configname: CONFIG_BATTERY_RX51

Linux Kernel Configuration
└─>Device Drivers
└─>Power supply class support
└─>Nokia RX-51 (N900) battery driver
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Say Y here to enable support for battery information on Nokia
RX-51, also known as N900 tablet.

source code:
drivers/power/supply/rx51_battery.c