ST-Ericsson AB8500 RTC

modulename: rtc-ab8500.ko

configname: CONFIG_RTC_DRV_AB8500

Linux Kernel Configuration
└─>Device Drivers
└─>Real Time Clock
└─>ST-Ericsson AB8500 RTC
In linux kernel since version 2.6.35 (release Date: 2010-08-01)  
Select this to enable the ST-Ericsson AB8500 power management IC RTC
support. This chip contains a battery- and capacitor-backed RTC.

source code:
drivers/rtc/rtc-ab8500.c