Re: USB 2 Switching
> I have a powerbook 12", and I'm running kernel 2.6.8-powerpc, Debian
> Sarge PPC. If i use the USB port for my external hard-drive it goes
> up to 15MB speed, which is fine. But, if I plug it out, use the usb
> mouse, and plug the HD again, it goes like a USB 1 speed, that's no
> more than 900 Kb/sec.
>
> Any idea why?
IIRC - the USB spec says that if you have devices of multiple speeds
on the same bus/hub, the ENTIRE hub drops in speed to that of the
slowest device. It is not clear from your description if you get the
900 kb/s with the mouse AND hard drive plugged-in together, or if it
is with just the hard drive after you use and remove the mouse. If it
is the former, that's just the behaviour of USB according to the spec.
If it is the latter, it means the bus/hub still thinks there is a USB
low-speed device attached, has not reset itself properly, and is still
running in the low-speed mode.
cheers
vinai
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