Thanks for that link, that pretty much explains why the Raspbian kernel patch exists. I only found some other docs that weren't as helpful. Since the Raspbian kernel devs seem to think that the patch is the best solution (see https://github.com/raspberrypi/linux/issues/1054), I don't think asking them (or even just me trying) to find a better solution acceptable for the upstream kernel is feasible. For now, I think I'll keep using my patched spidev module package and maybe I'll document the issue on the openSUSE:SPI wiki page.