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Re: usb hub problems



On Sat, 2006-07-29 at 17:55 -0700, Pete Zaitcev wrote:
> On Sat, 29 Jul 2006 23:13:59 +0200, Erwin Rol <mailinglists erwinrol com> wrote:

> Interesting. The -32 is a stall, e.g. a device intentionally terminates
> the transfer. Most likely, your hub simply does not support split
> USB 2.0 isochronous transactions, and the stall originates in the hub.

It is based (well pretty much is, because it is a one chip thing) on a
Cypress CY7C65640 that apparently has some configuration options that
make it possible to make highspeed transactions out of full/low speed
transactions. so when a downstream port is full speed the upstream port
will use highspeed transactions, that way all 4 downstream ports can
have a full 12Mbit/s bandwidth. A second configuration is that the
upstream transaction also will be full speed and than the 4 ports have
to share the 12Mbit/s upstream. To be honest i don't know what setting
the hub is in, but maybe trying the other setting would fix the
problem. 

Does Linux have any infrastructure to changes settings of HUB's like
this ?

- Erwin



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