Upon reading the title I thought this was going to be about how easy it is to write or modify a Linux driver when using a LLM even if you know nothing about the subject.

No LLM needed. Kernel driver code for simple things is usually copy-paste-modify. Find something that works with an HID interrupt based device, and modify that. If you want a /sys led, copy from that. It's only if you try to push to mainline you need to worry about understanding it, but they'd probably smell LLM trash from miles away.