From mboxrd@z Thu Jan  1 00:00:00 1970
From: <Narendra_K@Dell.com>
Subject: Re: [PATCH net-next] net: Add phys_port identifier to struct
 net_device and export it to sysfs
Date: Mon, 22 Jul 2013 04:46:01 -0700
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On Sun, Jul 21, 2013 at 08:18:23PM +0530, Ben Hutchings wrote:
> 
> On Sun, 2013-07-21 at 14:14 +0300, Or Gerlitz wrote:
> > On Sun, Jul 21, 2013 at 10:24 AM, Jiri Pirko <jiri@resnulli.us> wrote:
> > [...]
> >
> > Sorry, I missed that fact that initially you responded on this thread
> >
> > > The value could be anything. But note that you have to have different
> > > values for card1-port1,2 and card2-port1,2
> >
> > why?
> 
> The intent is to identify physical ports uniquely, so userland can tell
> whether two devices are backed by the same physical port.
> 
> But there's no requirement on the format, so you could ensure that one
> byte of this identifier is the port number on the board.

Would it be useful to embed the port number at a known offset to ensure
uniformity across all drivers, if a driver choses to embed port number
as part of phys_port_id ? 

-- 
With regards,
Narendra K
Linux Engineering
Dell Inc.