From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-04.galae.net (smtpout-04.galae.net [185.171.202.116]) (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 1FE6F299950 for ; Fri, 16 Jan 2026 14:00:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.171.202.116 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768572058; cv=none; b=XMHSAvepIYWIzR208nEbMRSRGIGZAJyZLFxYeavMZQJIVczfugT5xLuvHnCa6WeNOKazjEauHHopjx2bMMP6mM93mTYmk51v8c8cDwncxnrKoIgRxxDSqRmr5XLj86ZXFrTwPIXCs2FZprzjnR0f7FkCk/RS5tKCaFh6zL0fTDk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768572058; c=relaxed/simple; bh=5HJg1+r27vjf2hpwiUI/JpMFhcLfSGQf53bp9hNPWP0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GlkTnX/YgArA62CwtLs8E5Cwx+lNAARA31Pe6STlvnKMw5tHkvqXZCa4I6saG+4mVkEB88+UO0M9b2Ck6dGtzVOPiVW/gXkRbzjgW/FoX7gAEbL6M0ZuQifIFVwOZRNSJ1DAAinSaKlez+4d3/3XpomVZTYmVC+HKrqmLcU1GR8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=ScN0bD2r; arc=none smtp.client-ip=185.171.202.116 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="ScN0bD2r" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id 9EFBDC1F1FC; Fri, 16 Jan 2026 14:00:27 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 65FC760732; Fri, 16 Jan 2026 14:00:54 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 1AD0F10B68A9F; Fri, 16 Jan 2026 15:00:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1768572053; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=LB6Omhs0m/4Gl4M16+1Ov7LcTMAb+BD/AbzAvX1qW+w=; b=ScN0bD2rkbsnJzdBmQtH/DP9dpZdXBRPyXJoLiqw0Egr/8d+fcjxu/JXOzuD7Lh3EdNiTJ v7tAXMd6gauQtqGn/JJPnG+Pst+qEczKibMcA0GJa5gKOdur5A99w+fKvDm3Edd9E7MSqA y2Q9t9BcyiQYPgdJsptZTD9EWCnQiLUzMXxIKyFaXS/4OHKttCV9xxYKbjBrSgYnHboJZt NVWqL8mCoh5YNFYDi5V27stFKGJEZgF1jWGD4x6PQehqMA8x/lzmAWWN4CaJB0uv4a/Yje 999RIYwN0INg5c5UTr9/buj1mA5SDi83B95wUjff9hWfgHdNYHtIM9CDRoUJuA== Message-ID: Date: Fri, 16 Jan 2026 15:00:49 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v5] net: sfp: extend SMBus support To: Jonas Jelonek , Russell King , Andrew Lunn , Heiner Kallweit , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?Q?Bj=C3=B8rn_Mork?= References: <20260116113105.244592-1-jelonek.jonas@gmail.com> <6a87648c-a1e8-49a2-a201-91108669ab44@bootlin.com> <6987689b-35ac-4c15-addb-1c8e54144fa7@gmail.com> Content-Language: en-US From: Maxime Chevallier In-Reply-To: <6987689b-35ac-4c15-addb-1c8e54144fa7@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 On 16/01/2026 14:43, Jonas Jelonek wrote: > Hi, > > On 16.01.26 14:23, Maxime Chevallier wrote: >> I think Russell pointed it out, but I was also wondering the same. >> How do we deal with controllers that cannot do neither block nor >> single-byte, i.e. that can only do word access ? >> >> We can't do transfers that have an odd length. And there are some, >> see sfp_cotsworks_fixup_check() for example. >> >> Maybe these smbus controller don't even exist, but I think we should >> anyway have some log saying that this doesn't work, either at SFP >> access time, or at init time. > > I tried to guard that in the sfp_i2c_configure() right now. The whole path > to allow SMBus transfers is only allowed if there's at least byte access. For > exactly the reason that we need byte access in case of odd lengths. Then, > it can upgrade to word or block access if available. Or did I miss anything in > the conditions? Ah true, true. Should you need to respin, maybe add a comment for clueless people like myself :) I'll see if I can give this a test today then Thanks Maxime