Well, please see the updated declaration of snd_hda_ext_bus_init() in this very patch and then the existing code of sound/soc/intel/skylake/skl.c - skl_create(). Last argument in updated declaration reads 'modelname'. Skylake-driver has its own, SOF initializes it differently.
Not sure why you have your own?
Not sure I understand the question. If you are talking about changing string 'sklbus' to something else, then I don't believe mixing changes: update to actual values assigned and assignment relocation in one patch is good. I used 'sklbus' as that's what is being currently assigned to ->modelname within skl_create(). Such approach makes the change more transparent.
What I meant is that this 'modelname' is a module parameter for legacy and SOF driver, it's attached to the bus, but eventually used by the codec
hda_codec.c: if (codec->bus->modelname) { hda_codec.c: codec->modelname = kstrdup(codec->bus->modelname, GFP_KERNEL);
and even further down used to apply board-specific fixups.
"sklbus" doesn't seem to be related to codecs, boards or fixups, so not sure what this parameter does in the end?