From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752517AbcDZRZY (ORCPT ); Tue, 26 Apr 2016 13:25:24 -0400 Received: from mail-pf0-f171.google.com ([209.85.192.171]:34975 "EHLO mail-pf0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751851AbcDZRZW (ORCPT ); Tue, 26 Apr 2016 13:25:22 -0400 Subject: Re: [PATCH 1/6] bus: Add shared MDIO bus framework To: Andrew Lunn , Pramod Kumar References: <1461230323-27891-1-git-send-email-pramod.kumar@broadcom.com> <1461230323-27891-2-git-send-email-pramod.kumar@broadcom.com> <20160425205650.GA31129@lunn.ch> <666dffb41a922b0c8638f2f002a2de08@mail.gmail.com> <20160426121335.GC11668@lunn.ch> Cc: Rob Herring , Catalin Marinas , Will Deacon , Masahiro Yamada , Chen-Yu Tsai , Mark Rutland , devicetree@vger.kernel.org, Pawel Moll , Arnd Bergmann , Suzuki K Poulose , netdev@vger.kernel.org, Punit Agrawal , linux-kernel@vger.kernel.org, BCM Kernel Feedback , linux-arm-kernel@lists.infradead.org, Anup Patel From: Florian Fainelli Message-ID: <571FA3F6.7000903@gmail.com> Date: Tue, 26 Apr 2016 10:23:02 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160426121335.GC11668@lunn.ch> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 26/04/16 05:13, Andrew Lunn wrote: >> 4. Apart from these, by using MDIO mux framework we are making our >> non-ethernet PHYs dependent on Linux network drivers which is not >> acceptable. What if some product line does not need network subsystem at >> all? > > This is your only valid point. However, does Broadcom have a product > line which does not include networking? Is not Broadcom a network SoC > vendor? But even with that, there is no reason why we could not decouple the PHYLIB MDIO framework from PHYLIB and make it available as a more standalone subsystem which can be utilized when you have a mix of MDIO devices like here. I am not clear on how common a shared MDIO bus is on other SoCs, but the other Broadcom SoCs I am familiar with have dedicated MDIO buses instances per type of PHY (PCIe, BUSB, Ethernet), thus making the split a ton easier. -- Florian From mboxrd@z Thu Jan 1 00:00:00 1970 From: f.fainelli@gmail.com (Florian Fainelli) Date: Tue, 26 Apr 2016 10:23:02 -0700 Subject: [PATCH 1/6] bus: Add shared MDIO bus framework In-Reply-To: <20160426121335.GC11668@lunn.ch> References: <1461230323-27891-1-git-send-email-pramod.kumar@broadcom.com> <1461230323-27891-2-git-send-email-pramod.kumar@broadcom.com> <20160425205650.GA31129@lunn.ch> <666dffb41a922b0c8638f2f002a2de08@mail.gmail.com> <20160426121335.GC11668@lunn.ch> Message-ID: <571FA3F6.7000903@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 26/04/16 05:13, Andrew Lunn wrote: >> 4. Apart from these, by using MDIO mux framework we are making our >> non-ethernet PHYs dependent on Linux network drivers which is not >> acceptable. What if some product line does not need network subsystem at >> all? > > This is your only valid point. However, does Broadcom have a product > line which does not include networking? Is not Broadcom a network SoC > vendor? But even with that, there is no reason why we could not decouple the PHYLIB MDIO framework from PHYLIB and make it available as a more standalone subsystem which can be utilized when you have a mix of MDIO devices like here. I am not clear on how common a shared MDIO bus is on other SoCs, but the other Broadcom SoCs I am familiar with have dedicated MDIO buses instances per type of PHY (PCIe, BUSB, Ethernet), thus making the split a ton easier. -- Florian