[U-Boot] Need suggestion on device driver project ideas

Hi, Currently I am pursuing my M.tech in embedded system. I would like to do my final academic project on Linux Device Driver. Please suggest some good areas/driver subsystem/feature that can be a good project. It can be on Uboot/boot-loader as well. Some of the areas that I had in my mind are GSM module driver inclusion in embedded linux dev boards, WiFi driver for ESP8266, TrustZone security(Didn't get the resource, TPM is too costly). Please suggest As much as you can. I will open source the source code as well after my coursework is over.

Thanks & Regards Anupam