On Tue, 4 Oct 2005, Simon Burge wrote:
Jared and Quentin (both CC'd here) have some ideas on directly attaching the gpio to the opb. Jared set up the net4801 (i386) so that the gpio was directly attached to the PCI-ISA bridge. I'll let them speak up about that.
Well, on the NS Geode GX, you get the GPIO I/O base from reading a PCI configuration register on the PCI-ISA bridge. We simply map this region from within gscpcib(4), setup the GPIO glue, and call config_found (passing in the required gpiobus_attach_args).
I'm not sure how things work in OPB land -- is it possible for opb(4) to talk directly to the gpio pins? Or is your (old) gpio@opb a real device attached to an opb? If you can pull off the same trick that we use in gscpcib(4), you can certainly avoid having an extra device driver involved here.
Cheers, Jared