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Date:   Thu, 2 Apr 2020 13:42:00 +0200
From:   Oleksij Rempel <o.rempel@pengutronix.de>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Christian Herber <christian.herber@nxp.com>,
        Rob Herring <robh@kernel.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Mark Rutland <mark.rutland@arm.com>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        Marek Vasut <marex@denx.de>, netdev <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        David Jander <david@protonic.nl>,
        "David S. Miller" <davem@davemloft.net>,
        Heiner Kallweit <hkallweit1@gmail.com>
Subject: Re: Re: [PATCH v4 1/4] dt-bindings: net: phy: Add support for NXP
 TJA11xx
Message-ID: <20200402114200.GA15570@pengutronix.de>
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 <20200323151423.GA32387@lunn.ch>
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On Mon, Mar 23, 2020 at 04:14:23PM +0100, Andrew Lunn wrote:
> > Yes, it is one device with two address. This is if you call the entire IC a device. If you look at it from a PHY perspective, it is two devices with 1 address.
> > If you just look at it as a single device, it gets difficult to add PHY specific properties in the future, e.g. master/slave selection.
> 
> > In my opinion its important to have some kind of container for the
> > entire IC, but likewise for the individual PHYs.
> 
> Yes, we need some sort of representation of two devices.
> 
> Logically, the two PHYs are on the same MDIO bus, so you could have
> two nodes on the main bus.
> 
> Or you consider the secondary PHY as being on an internal MDIO bus
> which is transparently bridged to the main bus. This is what was
> proposed in the last patchset.
> 
> Because this bridge is transparent, the rest of the PHY/MDIO framework
> has no idea about it. So i prefer that we keep with two PHY nodes on
> the main bus. But i still think we need the master PHY to register the
> secondary PHY, due to the missing PHY ID, and the other constrains
> like resets which the master PHY has to handle.

Yes, this is the way how current patches are implemented.

Should dt-binding documentation and PHY changes go via David's tree
upstream?  If nobody has strong opinion against it, @David can you
please take them.

Regards,
Oleksij & Marc
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