Michael Niewöhner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/34948 )
Change subject: superio/nuvoton: add a driver for nct668xd ......................................................................
Patch Set 7:
Patch Set 6: Code-Review+1
Apart from the comment on patchset 4 on the enable function override for the GPIO LDNs this looks good to me. If you're not sure what I meant there, just say so and I'll try to explain it better :) I'm not sure if this might cause some issues, but you mentioned in the patch that changing the bits in register 0x30 of the GPIO LDNs might interfere with the embedded microcontroller in the SIO.
Let's see if I got this right - could you check this again, please? :-)