Re: wusb: use soft device reset?

On Monday 20 October 2008, David Vrabel wrote:
> The current WUSB device reset code uses a hard reset via the Reset
> Device IE which causes the device to enter the UnConnected state and
> (potentially) reconnect to a different fake port.  This breaks USB
> device drivers with .pre_reset and .post_reset methods.
> 
> Instead, I propose doing a soft reset of authenticated devices (the only
> state where this is valid) 

Makes sense to me  -- don't have the spec at hand, but if it is mentioned
setaddr(0) / setaddr(addr) equates a soft reset, it should be fine.

One thing to bear in mind is how well devices will respond to this. In 
theory reset means "do a full device reset". How true is this when doing
a soft reset might confuse a few drivers. Being pesimistic here, but you
might have a to have a plan B.

> and simply ignoring reset requests for 
> unauthenticated devices (these will eventually time out after
> TrustTimeout and disconnect themselves so they cannot get stuck in a
> funny state).

I'd keep the reset IE for those guys; as mentioned before, when we say
reset, we expect an inmediate reset.



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