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Date: Thu, 30 Aug 2007 15:13:12 -0500
From: Scott Wood <scottwood@freescale.com>
To: Vitaly Bordug <vitb@kernel.crashing.org>
Subject: Re: [PATCH 2/9] cpm2: Fix off-by-one error in setbrg().
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On Thu, Aug 30, 2007 at 02:09:07AM +0400, Vitaly Bordug wrote:
> On Tue, 28 Aug 2007 15:19:21 -0500
> Scott Wood wrote:
> 
> > The hardware adds one to the BRG value to get the divider, so it must
> > be subtracted by software.
> 
> Prolly a note why it used to work, or what exactly this is resulting in
> the code. IIRC this was just fw-ported so arch/ppc should have this as
> well.

It *didn't* work before -- hence the fix.

The failure mode from being off by just one isn't total nonfunctionality,
but rather a corrupted character now and then, which could explain why it
wasn't fixed before.

As for arch/ppc, I'm just trying to not break it more than it already is.

-Scott