From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7424FC001B0 for ; Mon, 10 Jul 2023 19:39:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230420AbjGJTjS (ORCPT ); Mon, 10 Jul 2023 15:39:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229811AbjGJTjP (ORCPT ); Mon, 10 Jul 2023 15:39:15 -0400 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C695D9E; Mon, 10 Jul 2023 12:39:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=O1YKh0iCibYzsm4hsCWbry564ZmymBSwh69WIn0oPJM=; b=svDqzOPyzOOPqTymB4KcsYSohE EnNrMhpo5uqx6SfFuNs/gqFoSzOUNocdni5V//pWJO0rhKU+55pvKYxVRWXifQLe5uUcfDUq6FUf0 T7g6F7zl+52RnGQ3gCy1Ir74sMuai5p6dKqzc5MFpW2kcvPo5vC8gJUV33SqEYkS4z84=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1qIwih-000yaT-6n; Mon, 10 Jul 2023 21:38:51 +0200 Date: Mon, 10 Jul 2023 21:38:51 +0200 From: Andrew Lunn To: Vesa =?iso-8859-1?B?SuTkc2tlbORpbmVu?= Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiner Kallweit , Russell King , Andrew Davis , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/2] net: phy: dp83822: Add support for line class driver configuration Message-ID: <6cf76d72-4747-46d2-a1f7-d2f1131491f7@lunn.ch> References: <20230710175621.8612-1-vesa.jaaskelainen@vaisala.com> <261cb91c-eb3a-4612-93ad-25e2bc1a7c23@lunn.ch> <87fac0dd-9a97-b188-4887-8c4bb21196d5@vaisala.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87fac0dd-9a97-b188-4887-8c4bb21196d5@vaisala.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Hi Andrew, > > This is needed for configuration in link between DP83822 and Ethernet Switch > chip. What switch chip is it? Most boards just connect the MACs together and don't have PHYs in the middle. There are some boards which do have PHYs, but they don't need any special mode. > In the connection there there is no Ethernet cable at all but routes > within the circuit boards but instead has capacitive coupling on routes. So you also left out the magnetics? > So the setting itself is related to specific circuit board design. Agreed. So it is then valid to put it into DT, if it is actually needed. > MLT-3 is related to encoding used in the signals -- I suppose wiki page is > good introduction reference: > > https://en.wikipedia.org/wiki/MLT-3_encoding MLT-3 is well defined. What i could not find is any reference to what reduced MLT-3 is. If it is not part of any standard, why don't you just hard code the PHY to always use MTL-3 which is defined as part of 802.3? I get the feeling reduced MLT-3 is TI proprietary. As such, it should default to MLT-3 as defined in 802.3 and there could then be an option to enable this proprietary mode for anybody we wants to use it. So before accepting any patches, we need a better understanding of that reduced MLT-3 is and why you would want to use it. Andrew