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Re: PCMCIA USB2.0 Card

Hello *,

I experienced similar problems as Hans.

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? 

* It seems to me that the ehci driver, in effect, is only used for 
recognizing the other hubs and routing the data traffic - but see below.

* It seems to me that hotplug does not correctly map the physical USB 
tree - instead it flattens the tree to a list.
I run kernel 2.6.10 and - at least - loading the device drivers works 
properly. With 2.6.8 the ehci driver failed with a fatal error but this 
event did not prevent hotplug from loading the ohci drivers. Moreover, I 
did some measurements with my USB flash memory stick and found that the 
USB 1.1 hubs are actually able to read at least 7 megabytes a second  
which is far in excess of USB 1.1 capabilities. So it seems that the USB 
1.1 hubs are running on high speed. It all doesn't fit and the question 
is: How should it really be?

I can give more information if required. Please give a list of commands, 
I'll run them and mail the output.


> See the runlevels if discover is enabled or not.
> Yes, hotplug is necessary. For the timebeing you could try blacklisting the 
> usb modules and then load them manually and try.
> Did you upgrade your kernel ? We've got 2.6.11 now. Try that !

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