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Date:   Sun, 28 Apr 2019 23:36:40 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Petr =?utf-8?Q?=C5=A0tetiar?= <ynezz@true.cz>
Cc:     netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        "David S. Miller" <davem@davemloft.net>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Alban Bedel <albeu@free.fr>
Subject: Re: [PATCH v2 3/4] net: macb: Drop nvmem_get_mac_address usage
Message-ID: <20190428213640.GB10772@lunn.ch>
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> so if I understand this correctly, it probably means, that this approach with
> modified of_get_mac_address is dead end as current of_get_mac_address users
> don't expect and handle possible -EPROBE_DEFER error, so I would need to
> change all the current users, which is nonsense.

Hi Petr

I would not say it is dead, it just needs a bit more work.

The current users should always be checking for a NULL pointer.  You
just need to change that to !IS_ERR(). You can then return
ERR_PTR(-PROBE_DEFER) from the NVMEM operation.

And i agree, wrapping this all up inside of_get_mac_address() is the
correct way to do this.

     Andrew