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Date:   Sat, 9 Feb 2019 20:34:09 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Rodolfo Giometti <giometti@enneenne.com>
Cc:     Florian Fainelli <f.fainelli@gmail.com>,
        Vivien Didelot <vivien.didelot@savoirfairelinux.com>,
        "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org
Subject: Re: Possible bug into DSA2 code.
Message-ID: <20190209193409.GI30856@lunn.ch>
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> So we I see two possible solutions:
> 
> 1) having both ds->slave_mii_bus and ds->ops->phy_read already defined is an
> error, then it must be signaled to the calling code, or

I don't think we can do that. mv88e6xxx optionally instantiates the
MDIO busses, depending on what is in device tree. If there is no mdio
property, we need the DSA core to create an MDIO bus.

Looking at the driver, ds->slave_mii_bus is assigned in
mv88e6xxx_setup().

We have talked about adding a teardown() to the ops structure. This
seems like another argument we should do it. The mv88e6xxx_teardown()
can set ds->slave_mii_bus back to NULL, undoing what it did in the
setup code.

      Andrew