Qualcomm PM8921 PMIC chip

modulename: pm8921-core.ko

configname: CONFIG_MFD_PM8921_CORE

Linux Kernel Configuration
└─>Device Drivers
└─>Multifunction device drivers
└─>Qualcomm PM8921 PMIC chip
In linux kernel since version 3 (release Date: 2011-07-21)  
If you say yes to this option, support will be included for the
built-in PM8921 PMIC chip.

This is required if your board has a PM8921 and uses its features,
such as: MPPs, GPIOs, regulators, interrupts, and PWM.

Say M here if you want to include support for PM8921 chip as a module.
This will build a module called "pm8921-core".

source code:

depends
CONFIG_MFD_SUPPORT
CONFIG_MSM_SSBI