Re: PCMCIA USB2.0 Card
On Mon, 14 Mar 2005, Derek Broughton wrote:
> On Monday 14 March 2005 04:23, Michael Marte wrote:
> > usbview tells me that there is root hub running at high speed (driven
> > by ehci) and two more hubs running at full speed (driven by ohci).
> > Interestinlgy, the full speed hubs are not children of the root hub but
> > occur on the same level of the USB device tree as the root hub. Some
> > thought and questions on this situation:
> > * Why are there three hubs - not only one?
> In short, because that's the way your hardware manufacturers and software
> configuration set it up. My Inspiron, with two USB ports, has two hubs.
> Doesn't seem necessary, but it's in the ACPI implementation, iirc. The "full
> speed" (ack! I hate that weasel term) hubs are there because you have ohci
> configured - why? If you have it compiled as a module, try removing it, then
> plugging something in - should still work, using ehci. When you plugged in a
> high-speed device, it bypassed the USB 1.1 hubs and went right to the 2.0 hub
> - which makes it pretty obvious why you can't have the 1.1 hubs as children
> of the root.
I blacklisted ohci and, in effect, USB devices connected to either of the
two ports are not recognized any more. I have to modprobe ohci to get them