On Saturday 12 January 2013 14:16:02 Andreas Mohr wrote: > > Greg, Linus, > > It sounds insane, but after banging on the issue I have found out that > > USB problem is caused (also in vanilla kernel) with a config change: > > USB-all built as modules - bad USB > > USB core built in, UHCI/EHCI modules - semi functional - but 1Mb/s > > transfer > > USB core and UHCI EHCI built-in - bingo - no issues. > > > > Could anybody duplicate that, or is it somehow my setup??? > > Since there was no additional reply here (needed) so far, > some of my (questionably relevant?) thoughts on this: > > There's of course the EHCI vs. UHCI(/OHCI) duality > (EHCI host controller responsible for high speed transfers, > the other for 1.1 full speed, both serving the same port connectors). > So if the coordination between the two is a problem, > you might end up with merely full speed on a 2.0 port. > > And with drivers builtin vs. module, the init sequence/timing > might possibly be affected - right? You should try EHCI first. This has always been true, but the likeliehood of seeing trouble is variable. This is testable. EHCI static, UHCI modular - should work EHCI modular, UHCI static - should fail Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
