Re: [PATCH RFC net-next 4/5] dt-bindings: net: dsa: mt7530: Add mediatek,ephy-handle to isolate ext. phy

From: Florian Fainelli <f.fainelli@gmail.com>
To: "René van Dorst" <opensource@vdorst.com>,
	sean.wang@mediatek.com, linux@armlinux.org.uk,
	davem@davemloft.net, matthias.bgg@gmail.com, andrew@lunn.ch,
	vivien.didelot@gmail.com
Cc: frank-w@public-files.de, netdev@vger.kernel.org,
	linux-mediatek@lists.infradead.org, linux-mips@vger.kernel.org
Subject: Re: [PATCH RFC net-next 4/5] dt-bindings: net: dsa: mt7530: Add mediatek,ephy-handle to isolate ext. phy
Date: Mon, 24 Jun 2019 14:56:50 -0700	[thread overview]
Message-ID: <e6175753-eb99-63e5-767e-f82becbf8d1a@gmail.com> (raw)
In-Reply-To: <20190624145251.4849-5-opensource@vdorst.com>

On 6/24/19 7:52 AM, René van Dorst wrote:
> On some platforum the external phy can only interface to the port 5 of the
> switch because the RGMII TX and RX lines are swapped. But it still can be
> useful to use the internal phy of the switch to act as a WAN port which
> connectes to the 2nd GMAC. This gives WAN port dedicated bandwidth to
> the SOC. This increases the LAN and WAN routing.
> 
> By adding the optional property mediatek,ephy-handle, the external phy
> is put in isolation mode when internal phy is connected to 2nd GMAC via
> phy-handle property.

Most platforms we have seen so far implement this logic with a mdio-mux,
can you see if that is possible here? stmmac has plenty of examples like
those.
-- 
Florian