ST-Ericsson AB8500 Power Regulators

modulename: ab8500-ext.ko

configname: CONFIG_REGULATOR_AB8500

Linux Kernel Configuration
└─>Device Drivers
└─>Voltage and Current Regulator Support
└─>ST-Ericsson AB8500 Power Regulators
In linux kernel since version 2.6.36 (release Date: 2010-10-20)  
This driver supports the regulators found on the ST-Ericsson mixed
signal AB8500 PMIC

source code:
drivers/regulator/