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Date:   Fri, 29 Jul 2022 18:32:20 +0200
From:   Oleksij Rempel <o.rempel@pengutronix.de>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Woojung Huh <woojung.huh@microchip.com>,
        Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, UNGLinuxDriver@microchip.com,
        Eric Dumazet <edumazet@google.com>, kernel@pengutronix.de,
        Paolo Abeni <pabeni@redhat.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        Vivien Didelot <vivien.didelot@gmail.com>
Subject: Re: [PATCH net v1 1/1] net: dsa: microchip: KSZ9893: do not write to
 not supported Output Clock Control Register
Message-ID: <20220729163220.GE10850@pengutronix.de>
References: <20220728131852.41518-1-o.rempel@pengutronix.de>
 <20220728222316.1d538cb3@kernel.org>
 <20220729094840.GB10850@pengutronix.de>
 <20220729084149.5a061772@kernel.org>
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On Fri, Jul 29, 2022 at 08:41:49AM -0700, Jakub Kicinski wrote:
> On Fri, 29 Jul 2022 11:48:40 +0200 Oleksij Rempel wrote:
> > On Thu, Jul 28, 2022 at 10:23:16PM -0700, Jakub Kicinski wrote:
> > > On Thu, 28 Jul 2022 15:18:52 +0200 Oleksij Rempel wrote:  
> > > > KSZ9893 compatible chips do not have "Output Clock Control Register 0x0103".
> > > > So, avoid writing to it.  
> > > 
> > > Respin will be needed regardless of the answer to Andrew - patch does
> > > not apply.  
> > 
> > Hm, this driver was hardly refactored in net-next. I'll better send it
> > against net-next otherwise things will break.
> 
> Probably fine either way, with the net-next patch (i.e. this patch) 
> on the list we shouldn't have problems resolving the conflict correctly.
> 
> The real question is whether it's okay for 5.19 to not have this patch.
> It'd be good to have the user-visible impact specified in the commit
> message.

So far I'm not aware about issues related to this, only warning in the data
sheet:
"RESERVED address space must not be written under any circumstances. Failure
to heed this warning may result in untoward operation and unexpected results."

I have send this patch as part of register access validation patch set.
There are move fixes any way.

Regards,
Oleksij
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