I figured out why i2c-voodoo3 and i2c-viapro weren't loading for me on some machines. The kernel PCI module init code (pci_module_init() in pci.h, then pci_register_driver() and pci_dev_driver() in pci.c) allows only one driver registration per PCI device. If another driver gets in there first we won't load. This is a big problem for drivers on multi-purpose PCI devices. Especially on our i2c bit-bangers for video chips, where we only use a couple of registers, and we have to coexist with video drivers. Do we have any choice but to back out some of the pci_module_init cleanup? Perhaps we need to go through each PCI driver and assess whether the PCI device it attaches to is "single-function"? Is there any easy way around this??? arghhhhhhhhhh...
