Parallelport support broken?

Yes, and that is why I thought you were trying to disable it.

I don’t know if parport_pc is still maintained, there is no reaction on the bug reports up to now.

I doubt it. This is a legacy interface, not in common use, and so for the most part set in concrete now days. Since, you’re able to configure it in such a way that it is working, I’d just consider this resolved and move on. If you really want to you could rebuild the module with ‘CONFIG_PARPORT_PC_FIFO=n’.