HN is possibly not the best place to ask questions such as these. You'd probably get better answers and also be able to have a follow up discussion by posting t

HN is possibly not the best place to ask questions such as these. You'd probably get better answers and also be able to have a follow up discussion by posting this question to a osdev or Linux kernel related mailing list (search for osdev or kernel newbies or even the dev mailing list for the distro of choice). All that said, to answer your question in brief, you have the right idea - even within the device driver layer you have various levels of abstraction. Whether you ultimately choose a certain level of abstraction is really specific to what you would like to do. If you find that an existing kernel module that provides a easy to work with interface via a device node, just make a userspace tool or library to suit your needs, if not, create your own kernel module.