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Date: Fri, 20 Apr 2012 17:25:25 +0800
From: Wang YanQing <udknight@gmail.com>
To: lkml <linux-kernel@vger.kernel.org>
Cc: linux-usb@vger.kernel.org
Subject: [RFC]Is usb port number fixed?
Message-ID: <20120420092525.GA12660@udknight>
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Hi!
when I execute the command below:

"ls /sys/bus/usb/devices/"

I get:
"1-0:1.0 1-1 1-1:1.0 2-0:1.0 2-1 2-1.1 2-1:1.0 2-1.1:1.0 2-1.5 2-1.5:1.0 2-1.5:1.1  usb1  usb2"

the output format is bus-port.port:config.interface
I want to know whether the port number is fixed after I reboot machine time by time.
And if it is fixed, then what make it.

Thanks!