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Date: Mon, 7 Jul 2008 07:01:24 -0400
From: Josh Boyer <jwboyer@linux.vnet.ibm.com>
To: benh@kernel.crashing.org
Subject: Re: [PATCH] [V2] powerpc: legacy_serial: reg-offset & shift aren't
	used
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Cc: dwg@au1.ibm.com, linuxppc-dev@ozlabs.org, paulus@samba.org,
	John Linn <john.linn@xilinx.com>
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On Mon, 07 Jul 2008 16:47:08 +1000
Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:

> On Tue, 2008-07-01 at 10:52 -0700, John Linn wrote:
> > The legacy serial driver does not work with an 8250
> > type UART that uses reg-offset and reg-shift. This
> > change updates the driver so it doesn't find the UART
> > when those properties are present on the UART in the
> > device tree for soc devices.
> > 
> > Signed-off-by: John Linn <john.linn@xilinx.com>
> > Acked-by: Grant Likely <grant.likely@secretlab.ca>
> > ---
> > V2
> > 
> > Corrected logic to use "||" rather than "&&".
> 
> I have some problems with this patch:
> 
>  - First if the properties are present but their value match the
> register layout of a standard UART, we will bail out... not nice.

Why would they be present in that case?

>  - Why don't we just implement support for the reg-shift and
> offset instead ?

Probably because the last time someone suggested that it spawned a
lengthy debate about what reg-offset/shift were supposed to do.

josh