On 20/11/14(Thu) 10:25, Remco wrote: > Ted Unangst wrote: > > > Roughly the same symptoms seen with an Intel Series 7 xhci. USB 3 > > drive is not detected in a USB 3 port. Drive works in the USB 2 port; > > USB 2 keyboard, etc. work in USB 3 port. > > Concerning the "USB2 device works in USB3 port" thingie, is it possible that > your USB2 devices end up being attached to an EHCI controller i.o. the xHCI > controller, even though they're connected through the blue port ?
If the BIOS is configured to route them to an EHCI controller. > I vaguely remember from looking at the xHCI spec that the interface behind > the blue port can switch between USB3 and USB2/USB1 mode. xHCI controller supports all these modes, but it's a different question (8. > I wonder, are USB2 devices working because they're simply connected to > the xHCI port in USB2/USB1 mode, maybe using a totally different code path > (EHCI i.o. xHCI) ? The problem here is not about the hardware, it's about the software. Various people having an Intel Series 7 or 8 xHCI controller reported timeouts issues with the xhci(4) driver. So the "workaround" is to not use the xhci(4) driver.
