From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Glauber <jan.glauber@caviumnetworks.com>
Subject: Re: [PATCH 4/5] i2c: octeon,thunderx: Check bus state before
 starting a transaction
Date: Thu, 22 Sep 2016 18:08:32 +0200
Message-ID: <20160922160832.GA2734@hardcore>
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To: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, "Bazhenov, Dmitry" <dmitry.bazhenov@auriga.com>

On Wed, Sep 21, 2016 at 10:55:41PM +0200, Wolfram Sang wrote:
> On Wed, Sep 21, 2016 at 08:51:05AM +0200, Jan Glauber wrote:
> > Add an additional status check before starting a transaction and,
> > if required, trigger the recovery if the check fails.
> > 
> > Signed-off-by: Jan Glauber <jglauber@cavium.com>
> 
> Won't this break multi-master setups?
> 

I'm afraid yes. I don't have a multi-master setup, but agree that we
should not break it.

How about re-checking if the bus is idle until a timeout
(i2c->adap.timeout ?) happens and only then recover?

Additionaly we can check for arbitration loss as Dmitry did in his
original patch.

--Jan