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Date:   Sat, 24 Mar 2018 15:48:50 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Florian Fainelli <f.fainelli@gmail.com>
Cc:     Alexandre Belloni <alexandre.belloni@bootlin.com>,
        "David S . Miller" <davem@davemloft.net>,
        Allan Nielsen <Allan.Nielsen@microsemi.com>,
        razvan.stefanescu@nxp.com, po.liu@nxp.com,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mips@linux-mips.org,
        James Hogan <jhogan@kernel.org>
Subject: Re: [PATCH net-next 6/8] MIPS: mscc: Add switch to ocelot
Message-ID: <20180324144850.GB31941@lunn.ch>
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On Fri, Mar 23, 2018 at 03:11:23PM -0700, Florian Fainelli wrote:
> On 03/23/2018 03:06 PM, Andrew Lunn wrote:
> >>> That is the trade off of having a standalone MDIO bus driver.  Maybe
> >>> add a phandle to the internal MDIO bus? The switch driver could then
> >>> follow the phandle, and direct connect the internal PHYs?
> >>
> >> This is more or less what patch 7 does, right?
> > 
> > Patch 7 does it in DT. I'm suggesting it could be done in C. It is
> > hard wired, so there is no need to describe it in DT. Use the phandle
> > to get the mdio bus, mdiobus_get_phy(, port) to get the phydev and
> > then use phy_connect().
> 
> That does not sound like a great idea. And to go back to your example
> about DSA, it is partially true, you will see some switch bindings
> defining the internal PHYs (e.g: qca8k), and most not doing it (b53,
> mv88e6xxx, etc.). In either case, this resolves to the same thing
> though. Being able to parse a phy-handle property is a lot more
> flexible, and if it does matter that the PHY truly is internal, then the
> 'phy-mode' property can help reflect that.

Hi Florian

With DSA, you can always provide a phy-handle. It is only when there
is nothing specified that the fallback case is used to map internal
PHYs to ports.

Putting internal PHYs in DT is fine, but it is a nice simplification
if it is not needed.

   Andrew