This is inside the kernel. There is a tegre_defconfig file to define which options are enabled/disabled in our kernel driver.
Download the kernel source code from
https://developer.nvidia.com/embedded/linux-tegra-archive
Follow the document here to build the kernel on the host.
Replace your kernel to /boot/Image on the device and reboot.
And just some precaution that rebuilding kernel has chance to crash the system so using uart serial console might be helpful.