Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753939AbdHUOXb (ORCPT ); Mon, 21 Aug 2017 10:23:31 -0400 Received: from vps0.lunn.ch ([178.209.37.122]:37186 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753210AbdHUOX3 (ORCPT ); Mon, 21 Aug 2017 10:23:29 -0400 Date: Mon, 21 Aug 2017 16:23:21 +0200 From: Andrew Lunn To: Maxime Ripard Cc: Chen-Yu Tsai , Corentin Labbe , Rob Herring , Mark Rutland , Russell King , Giuseppe Cavallaro , Alexandre Torgue , devicetree , linux-arm-kernel , linux-kernel , netdev Subject: Re: [PATCH v3 3/4] net: stmmac: register parent MDIO node for sun8i-h3-emac Message-ID: <20170821142321.GE1703@lunn.ch> References: <20170818122118.4925-1-clabbe.montjoie@gmail.com> <20170818122118.4925-4-clabbe.montjoie@gmail.com> <20170819185025.GB13266@Red> <20170819203836.GA21567@lunn.ch> <20170820065757.GA6081@Red> <20170820142545.GB24150@lunn.ch> <20170821132015.GB1703@lunn.ch> <20170821133104.qvrhvwin2rdg4aqo@flea.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170821133104.qvrhvwin2rdg4aqo@flea.lan> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 42 > All muxes are mostly always represented the same way afaik, or do you > want to simply introduce a new compatible / property? + mdio-mux { + compatible = "allwinner,sun8i-h3-mdio-switch"; + mdio-parent-bus = <&mdio_parent>; + #address-cells = <1>; + #size-cells = <0>; + + internal_mdio: mdio@1 { reg = <1>; - clocks = <&ccu CLK_BUS_EPHY>; - resets = <&ccu RST_BUS_EPHY>; + #address-cells = <1>; + #size-cells = <0>; + int_mii_phy: ethernet-phy@1 { + compatible = "ethernet-phy-ieee802.3-c22"; + reg = <1>; + clocks = <&ccu CLK_BUS_EPHY>; + resets = <&ccu RST_BUS_EPHY>; + phy-is-integrated; + }; + }; + mdio: mdio@0 { + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; }; Hi Maxim Anybody who knows the MDIO-mux code/binding, knows that it is a run time mux. You swap the mux per MDIO transaction. You can access all the PHY and switches on the mux'ed MDIO bus. However here, it is effectively a boot-time MUX. You cannot change it on the fly. What happens when somebody has a phandle to a PHY on the internal and a phandle to a phy on the external? Does the driver at least return -EINVAL, or -EBUSY? Is there a representation which eliminates this possibility? Andrew