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Date: Mon, 23 Apr 2012 09:52:12 +0800
From: Wang YanQing <udknight@gmail.com>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Anil Nair <anilcoll90@gmail.com>, Greg KH <greg@kroah.com>,
        lkml <linux-kernel@vger.kernel.org>, linux-usb@vger.kernel.org
Subject: Re: [RFC]Is usb port number fixed?
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On Sun, Apr 22, 2012 at 08:47:24AM -0400, Alan Stern wrote:
> On Sun, 22 Apr 2012, Anil Nair wrote:
> 
> > The port number comes from root hub managed by the host controller. Its
> > fixed dynamically during enumeration, and can change.
> > Please correct me if i am wrong.
> 
> You are indeed wrong.  Port numbers are not fixed dynamically and they 
> cannot change.
Right?
Could you pin out the codes in kernel?
> 
> On the other hand, bus numbers _are_ assigned dynamically and they can 
> (and do) change.
> 
Indeed, I never meat the situation lspci output different bus number on the same machine.
Any more comment?