Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752663AbbKIRI4 (ORCPT ); Mon, 9 Nov 2015 12:08:56 -0500 Received: from vps0.lunn.ch ([178.209.37.122]:48415 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752487AbbKIRIv (ORCPT ); Mon, 9 Nov 2015 12:08:51 -0500 Date: Mon, 9 Nov 2015 18:08:49 +0100 From: Andrew Lunn To: Arnd Bergmann Cc: netdev@vger.kernel.org, Thomas Petazzoni , Florian Fainelli , linux-kernel@vger.kernel.org, Stas Sergeev , "David S. Miller" , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] mvneta: add FIXED_PHY dependency Message-ID: <20151109170849.GC3388@lunn.ch> References: <4225885.EYXTHjRPmX@wuerfel> <20151109164232.GB3388@lunn.ch> <6910088.dNmooXDTJR@wuerfel> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6910088.dNmooXDTJR@wuerfel> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1361 Lines: 29 > > I suppose it comes down to, are we allowed to optionally implement > > part of the DT binding? > > I'm not sure what you are asking. A lot of DT bindings have both > optional and mandatory properties. For mvneta, the "phy" and "phy-mode" > properties are listed as mandatory, so the driver can safely assume > that they are always present. If there are reasons to leave them out, > and for the driver to handle that case correctly, the binding > should be updated to mark them as optional. Hi Arnd You are looking at it from the perspective of the driver. I was meaning from the perspective of the DT blob. Can be blob assume the driver implements all of the binding, all of the time? You use fixed-phy when the MAC is connected to a switch, not a phy. Or when the MAC is connected to an SFP module. The driver can currently be built to not implement the fixed-phy party of the binding. Is that O.K. from the perspective of the DT blob? Or should the driver always implement all of the binding, in which these NOP stubs should be removed and fixed phy always be enabled for the drivers that use it. Andrew -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/