On Wednesday 11 June 2008, Maciej W. Rozycki wrote: > > That being said, I'm not sure if the comparison with the PCI subsystem > > holds... I am under the impression that PCI bus handling doesn't > > require dedicated drivers? At least I can't see any under drivers/pci. > > Of course it does require them. It is just due to their very nature they > tend to be placed under arch/,
PCI root hubs, yes. The drivers/pci/hotplug bridges are slightly more generic, ditto drivers/pci/pcie and the CardBus bridges in drivers/pcmcia. At one point, lack of a generic (non-hotplug) PCI bridge driver was viewed as a weakness of that driver stack. Also, drivers/acpi/pci_root.c binds the root at subsys_initcall. That's done *after* some earlier PCI magic; I never bothered to sort through that little maze. > although there are some cases where the > same system controller can be used for a range of processors (e.g. some > Marvell chips can be used either with MIPS or PowerPC CPUs) and they might > be arguably put in a place more suitable for sharing between > architectures. See arch/mips/pci/ for an example of a generous bunch of > PCI host drivers. Which, for the record, get very early initialization using two different mechanisms: - many use arch_initcall() - the "arch" subtree is linked before the "drivers" subtree I don't think I2C needs to worry about arch_initcall just now, but if necessary it could initialize earlier than subsys_initcall. - Dave _______________________________________________ i2c mailing list [email protected] http://lists.lm-sensors.org/mailman/listinfo/i2c
