Helloworld on HAL development

Hi folk, I’m trying to learn the HAL development/source code analyse with the following setup

  1. Radax 4 board
  2. Android TV 9 repo

The driver hardware/rockchip/liblights seems to be very easy to understand. But it seems like it’s not enabled during configuration period. So I’ve got two questions

  1. Is it possible to enable this module with my setup? And which config option?
  2. If it’s impossible to enable, is there other beginner friendly HAL drivers to look into?

Cheers.