AT91SAM9x/AT91CAP9

modulename: rtc-at91sam9.ko

configname: CONFIG_RTC_DRV_AT91SAM9

Linux Kernel Configuration
└─>Device Drivers
└─>Real Time Clock
└─>AT91SAM9x/AT91CAP9
In linux kernel since version 2.6.25 (release Date: 2008-04-16)  
RTC driver for the Atmel AT91SAM9x and AT91CAP9 internal RTT
(Real Time Timer). These timers are powered by the backup power
supply (such as a small coin cell battery), but do not need to
be used as RTCs.

(On AT91SAM9rl chips you probably want to use the dedicated RTC
module and leave the RTT available for other uses.)

source code: