Date:   Thu, 25 Nov 2021 16:20:44 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Wells Lu =?utf-8?B?5ZGC6Iqz6aiw?= <wells.lu@sunplus.com>
Cc:     Wells Lu <wellslutw@gmail.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "p.zabel@pengutronix.de" <p.zabel@pengutronix.de>,
        Vincent Shih =?utf-8?B?5pa96YyV6bS7?= 
        <vincent.shih@sunplus.com>
Subject: Re: [PATCH v2 2/2] net: ethernet: Add driver for Sunplus SP7021
Message-ID: <YZ+pzFRCB0faDikb@lunn.ch>
References: <cover.1636620754.git.wells.lu@sunplus.com>
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 <7cccf9f79363416ca8115a7ed9b1b7fd@sphcmbx02.sunplus.com.tw>
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> Due to hardware design, we still need to set PHY address,
> because MDIO controller of SP7021 only sends out MDIO 
> commands with the same address listed in PHY address 
> registers. The function below needs to be kept.

I suggest you actually set it to some other address. One of the
good/bad things about MDIO is you have no idea if the device is
there. A read to a device which does not exist just returns 0xffff,
not an error. So i would set the address of 0x1f. I've never seen a
PHY actually use that address.

    Andrew