On Monday 13 February 2006 2:19 pm, Alan Stern wrote: > > In pci-quirks.c, the UHCI handoff code is called by uhci-hcd when the > controller is initialized, regardless of whether it has already run as > part of the PCI initialization. Similarly, the OHCI handoff code is > duplicated in ohci_init(), so it runs even if the pci-quirks code gets > skipped.
I don't know why you do that for UHCI, but for OHCI the reason for the code duplication is: just in case some non-PCI system needs the handoff. That seems to be a purely theoretical case just now. > However the EHCI handoff is not called anywhere in ehci-hcd. If the > quirks code doesn't run then the handoff will never take place. Right; EHCI handoff (unlike OHCI) is specified as PCI-specific; those registers sit in PCI config space. > Some systems require that the OHCI handoff not take place at the time the > quirk_usb_early_handoff routine runs, but only later (after the i8042 has > been initialized). It's possible that other systems may end up having a > similar requirement for the EHCI handoff. Or UHCI. But the input system isn't ready to handle such stuff yet, right? > Do you think it's a good idea to have ehci-hcd essentially call > quirk_usb_disable_ehci() as part of its controller initialization? Only with a paired update of the input subsystem. Remember that the reason we moved that "early" handoff to become the standard model -- and haven't changed it, even though it turned up bugs on some boards for _all_ the PCI based USB host controller drivers -- is that the input folks needed it... - Dave ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel