From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B5022FF65F; Fri, 16 Jan 2026 11:21:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768562495; cv=none; b=nCDEuZdVW6arGbWxvfqLozQ5Pn6IWBIZifTyL8rtaJ6Ja8x85EWZhD97Va0WERtIynPtqilG7g8FXKFjVB27BhMCPxhPFDVYq0PfJKMLcRCVcvUuK1jVDZA1xIVqWRpxcLtcEj7sFpbsM4DlwmIa9MFebLM3NsQlYPiGx+WoT6Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768562495; c=relaxed/simple; bh=8AvaulKIS+LglmFonRB2jt85nfPGs7h6Z60XGPl7n6I=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Xhhq8kyk26F2RuXebf3nrDofIp47Z7noaNi9DhpR6qAFKR4jVBK5i+yzjXtgmjrdyYZzZZqhw8orbszA2ZbFF9+wMtBM4mmDH0iDrMmpiKMxjgNzGHfePqjtdBoNEnLxkZx3FhVa+ZmiVRWEcwEYDiJ0OAfaMeEl8+aS6pSYGuo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=khFazCMl; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="khFazCMl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=G+eYF1EdvyXkLboVNLbmsCw9+IK3+4mhBbVGMSLho3A=; b=khFazCMlbVS5BtGHDU23tsWrOv pGL+ABZnDx2OCuv0L1ZRT/6PaXaoVKZFn92Cvbwce53uczTvaY4ljskR9od8pOKF0gJBWk9et3L7M 2mqBGtA5dy9/rP7jNwhmKAmjsLk1feqVKZT4Gw6mCHd8BJF2wrJ2rWIFgwiuzZKiJPBeH8xF8q0RA qmY2CvNhIOr1xXVfxZ+Iut3j8ZOBPBgMSr9mxGP7BUIHGs9Adt+RQGPwbAkPVt6g8yd5VFQ/Vje8A azaWpm8LeoCvjNyhAJWnFDPXmz1VJ1jpDNFe3hTGTsSa+Fajqke58II3oz3mb4v5hlJYvawXvyKk6 1EC0x9yg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:55848) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vghtO-000000002Bl-1sL6; Fri, 16 Jan 2026 11:21:26 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1vghtL-000000003ZO-1zdt; Fri, 16 Jan 2026 11:21:23 +0000 Date: Fri, 16 Jan 2026 11:21:23 +0000 From: "Russell King (Oracle)" To: Jonas Jelonek Cc: Maxime Chevallier , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?iso-8859-1?Q?Bj=F8rn?= Mork , Paolo Abeni , Jakub Kicinski , Eric Dumazet , "David S . Miller" , Andrew Lunn , Heiner Kallweit Subject: Re: [PATCH net-next v4] net: sfp: add SMBus I2C block support Message-ID: References: <20260109101321.2804-1-jelonek.jonas@gmail.com> <466efdd2-ffe2-4d2e-b964-decde3d6369b@bootlin.com> <397e0cdd-86de-4978-a068-da8237b6e247@gmail.com> <0c181c3d-cb68-4ce4-b505-6fc9d10495cd@bootlin.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Russell King (Oracle) On Fri, Jan 16, 2026 at 12:16:11PM +0100, Jonas Jelonek wrote: > Hi Maxime, > > On 09.01.26 18:03, Maxime Chevallier wrote: > > ACK, I'll gladly help with testing. This should actually be easily > > achievable with a board that has a real i2c interface connected to the > > SFP cage, as there's a i2c smbus emulation layer. The SMBus helpers will > > work with a true I2C adapter, you may have to tweak the code though. > > > > This is relevant for modules that have a built-in PHY that you can > > access, if you don't have any I can run some tests here, I have more > > than enough modules... > > > > If you don't have time at all for that, I may give this a shot at some > > point, but my time is a bit scarce right now :'( > > > > I'd postpone this part if that's ok. Quite busy at the moment :( > > When I come to trying to work on that, should that all be kept in > mdio-i2c.c? I'm asking because we have a downstream implementation > moving that SMbus stuff to mdio-smbus.c. This covers quite a lot right > now, C22/C45 and Rollball, but just with byte access [1]. Because that > isn't my work, I'll need to check with the original authors and adapt this > for an upstream patch, trying to add word + block access. > > Kind regards, > Jonas > > [1] https://github.com/openwrt/openwrt/blob/66b6791abe6f08dec2924b5d9e9e7dac93f37bc4/target/linux/realtek/patches-6.12/712-net-phy-add-an-MDIO-SMBus-library.patch My personal view on this is not suitable for sharing publicly. I'm sure people can guess what my view is and why. (Look at the age of the patch, and it's clearly "lets re-implement mdio-i2c" rather than "let's adapt it". -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!