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Date:   Tue, 14 Jun 2022 20:46:48 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc:     netdev@vger.kernel.org, Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        devicetree@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Dan Murphy <dmurphy@ti.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next 1/3] dt-bindings: dp83867: add binding for
 io_impedance_ctrl nvmem cell
Message-ID: <YqjXmInBfE/oMc4m@lunn.ch>
References: <20220606202220.1670714-1-linux@rasmusvillemoes.dk>
 <20220606202220.1670714-2-linux@rasmusvillemoes.dk>
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On Mon, Jun 06, 2022 at 10:22:18PM +0200, Rasmus Villemoes wrote:
> We have a board where measurements indicate that the current three
> options - leaving IO_IMPEDANCE_CTRL at the (factory calibrated) reset
> value or using one of the two boolean properties to set it to the
> min/max value - are too coarse.
> 
> There is no documented mapping from the 32 possible values of the
> IO_IMPEDANCE_CTRL field to values in the range 35-70 ohms, and the
> exact mapping is likely to vary from chip to chip. So add a DT binding
> for an nvmem cell which can be populated during production with a
> value suitable for each specific board.
> 
> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew