i.MX21 pinctrl driver

modulename: pinctrl-imx21.ko

configname: CONFIG_PINCTRL_IMX21

Linux Kernel Configuration
└─>Device Drivers
└─>Pin controllers
└─>i.MX21 pinctrl driver
In linux kernel since version 3.18 (release Date: 2014-12-07)  
Say Y here to enable the i.MX21 pinctrl driver

source code: