Well, a better answer would be, "it depends." Take your driver in source
form, attempt to compile it with reference to your kernel sources. (Which you'll have to do anyhow.) If it compiles okay, try it. But if it doesn't, you're faced with rewriting
where I'd hit the proverbial STOP
button, and look for "plan B.")
I would search carefully for a Wacom tablet driver that is
built for your kernel, or seriously consider upgrading your kernel. I just don't think that you really are "cutting new ground" here, unless you mean it as an exercise.