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From: Oliver Neukum <oliver@neukum.org>
To: Alan Stern <stern@rowland.harvard.edu>
Subject: Re: loading firmware while usermodehelper disabled.
Date: Sat, 31 Dec 2011 16:59:48 +0100
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Am Samstag, 31. Dezember 2011, 16:33:12 schrieb Alan Stern:

> Nothing has changed in the USB layer -- it has always been true that
> devices could be reset during a suspend/resume cycle.  This isn't a
> matter of how the stack is written or anything like that; some
> motherboards simply do not provide suspend power to their USB
> controllers.  Or the firmware reinitializes the controllers and
> attached devices during resume, forcing Linux's USB core to reset
> every device on the affected buses.
> 
> When it comes to suspend/resume, there are almost no guarantees.  :-(

We are definitely going through do_unbind_rebind(). But I don't think
it matters why we got there. We seem to be calling probe() too early.
And we need to guarantee that a driver can request firmware in probe()

So something has changed in the resume code path further up.

	Regards
		Oliver