Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Sun, 30 Apr 2023 20:48:37 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     =?utf-8?B?QXLEsW7DpyDDnE5BTA==?= <arinc.unal@arinc9.com>
Cc:     David Bauer <mail@david-bauer.net>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Landen Chao <Landen.Chao@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>,
        Sean Wang <sean.wang@mediatek.com>,
        Daniel Golle <daniel@makrotopia.org>, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org
Subject: Re: [PATCH 2/2] dt-bindings: net: dsa: mediatek,mt7530: document
 MDIO-bus
Message-ID: <207753d6-cffd-4a23-be16-658d7c9ceb4a@lunn.ch>
References: <20230430112834.11520-1-mail@david-bauer.net>
 <20230430112834.11520-2-mail@david-bauer.net>
 <e4feeac2-636b-8b75-53a5-7603325fb411@arinc9.com>
 <396fad42-89d0-114d-c02e-ac483c1dd1ed@arinc9.com>
 <04cc2904-6d61-416e-bfbe-c24d96fe261b@lunn.ch>
 <a6c6fe83-fbb5-f289-2210-6f1db6585636@arinc9.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <a6c6fe83-fbb5-f289-2210-6f1db6585636@arinc9.com>
Precedence: bulk

> > Try setting ds->slave_mii_bus to the MDIO bus you register via
> > of_mdiobus_register().
> 
> That seems to be the case already, under mt7530_setup_mdio():
> 
> 	bus = devm_mdiobus_alloc(dev);
> 	if (!bus)
> 		return -ENOMEM;
> 
> 	ds->slave_mii_bus = bus;
> 
> The bus is registered with devm_of_mdiobus_register(), if that matters. (My
> current knowledge about OF or OF helpers for MDIO is next to nothing.)
> 
> The same behaviour is there.

Maybe take a look at what is going on in dsa_slave_phy_setup() and
dsa_slave_phy_connect().

The way i understand it, is it first looks in DT to see if there is a
phy-handle, and if there is, it uses it. If not, it assumes there is a
1:1 mapping between port number and PHY address, and looks to see if a
PHY has been found on ds->slave_mii_bus at that address, and uses it.

So i don't think you need to list the PHY, the fallback should be
used.

	Andrew