CONFIG_VIDEOMODE_HELPERS (not configurable)

modulename: display_timing.ko

and/or

of_display_timing.ko

configname: CONFIG_VIDEOMODE_HELPERS

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>VIDEOMODE_HELPERS
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
drivers/video/