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 X-Spam-Level: X-Spam-Status: No, score=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AECB4C49EA3 for ; Mon, 28 Jun 2021 15:08:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AFAC61414 for ; Mon, 28 Jun 2021 15:08:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235665AbhF1PKh (ORCPT ); Mon, 28 Jun 2021 11:10:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:39702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236104AbhF1PHk (ORCPT ); Mon, 28 Jun 2021 11:07:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7F3ED613FD; Mon, 28 Jun 2021 14:58:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624892301; bh=HsQz+eG06TzAb3HbY3JdUc6LQkxeCoRIcHF3y10TQ+Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZVOvoruMYHVhjj1s9pjQE/Aw1s+xTb2/9/1JCF6tZd4BsiX9Bs6Mp9zskJOHy7VF6 0mLmmtpq7YBd/uzGdrLBiHS0f6dWAhtedwzFyed+Zzcw/+t7lmYxPUbsArRJFoz64D G77Oxmqf0KbyrItRSd9lKiAwxLg+RSZRSZsRJW13BpwMOPMsdekuet042fL5vYi1rM fKgiWJSku7nULuw544GP81w+ZRqhlKfUqoFbAi1ujEDDkog/GgWbanclu+JPLy/mm3 K34g7zrN5YdeJYYjf3PTy/vWpNAfuSBjm9H3Yb/BeFGOnYDsw7lZYCy4lW3wWv4rtQ 2UFPIbWnIlwFw== Date: Mon, 28 Jun 2021 16:58:15 +0200 From: Wolfram Sang To: Arnd Bergmann Cc: Jie Deng , Linux I2C , virtualization@lists.linux-foundation.org, Linux Kernel Mailing List , "Michael S. Tsirkin" , Jason Wang , Andy Shevchenko , conghui.chen@intel.com, kblaiech@mellanox.com, jarkko.nikula@linux.intel.com, Sergey Semin , Mike Rapoport , loic.poulain@linaro.org, Tali Perry , Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= , Bjorn Andersson , yu1.wang@intel.com, shuo.a.liu@intel.com, Viresh Kumar , Stefan Hajnoczi , Paolo Bonzini Subject: Re: [PATCH v10] i2c: virtio: add a virtio i2c frontend driver Message-ID: Mail-Followup-To: Wolfram Sang , Arnd Bergmann , Jie Deng , Linux I2C , virtualization@lists.linux-foundation.org, Linux Kernel Mailing List , "Michael S. Tsirkin" , Jason Wang , Andy Shevchenko , conghui.chen@intel.com, kblaiech@mellanox.com, jarkko.nikula@linux.intel.com, Sergey Semin , Mike Rapoport , loic.poulain@linaro.org, Tali Perry , Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= , Bjorn Andersson , yu1.wang@intel.com, shuo.a.liu@intel.com, Viresh Kumar , Stefan Hajnoczi , Paolo Bonzini References: <226a8d5663b7bb6f5d06ede7701eedb18d1bafa1.1616493817.git.jie.deng@intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="x7HUe2JbQ8ROazkf" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --x7HUe2JbQ8ROazkf Content-Type: text/plain; charset=us-ascii Content-Disposition: inline > You can fine Viresh's vhost-user implementation at > https://lore.kernel.org/qemu-devel/cover.1617278395.git.viresh.kumar@linaro.org/t/#m3b5044bad9769b170f505e63bd081eb27cef8db2 It looks OK so far; yet, it is not complete. But it might be bearable in the end. > As you say, it does get a bit clumsy, but I think there is also a good argument > to be made that the clumsiness is based on the host Linux user interface > more than the on the requirements of the physical interface, > and that should not have to be reflected in the virtio specification. Makes sense to me. > Right, this one has come up before as well: the preliminary result > was to assume that this probably won't be needed, but would be easy > enough to add later if necessary. If adding support incrementally works for such an interface, this makes sense as well. So, where are we? As I understand, this v10 does not support I2C transactions (or I2C_RDWR as you said). But you want to support all clients. So, this doesn't match, or? --x7HUe2JbQ8ROazkf Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmDZ44MACgkQFA3kzBSg KbZiNRAAg3+smsUmLAlo8w15thKTdKhG6yNDBD+TxkLusukTvHLa5j7KBjzDW+8L TgeVVbK6h4x9T21E0ofnkT8wUFquxCDC+h80FYIS/wMcISrLFDZAjW6M9Gjftzho pMW6jKibH9oKHZdvfnE3S5wCHGveCcBtztoTxUVELJop2HXj3OXhyCgtlo52PR2u rNIEjRsp+gSunOpu3c6U+70Hh+gmvTuFBWinAuelHCVqjoC9WbHbP3l0khP72y6A bDWWZk5e0Z3AHEoPlOXEWScNB0b/ScL6ZAkj19Q/JOrYFeDAAc4FdkE33HfX4J8h TbbwDRLxejCFyIfKfoIXGYxjihWwjdfZDkRspPy9i5gLCK6tfEcFCw/g+vSmisBh Xp6eQMqgFKiiFsBljSGRN8rEHrJKcysQXrL34QAPb5/ZK7PlRNtdBJBG6kWNkKLJ YjuLf2zkB0dD4fOwhHEYs7jbA2WDSNy3vJHVkqxyVOLClX67KTZMO8ShhHSFnSsA YZRJhbWAYvpZTrVRr54uvaWkv8VYL/BSx4N9DJE6ZbtHcVH2ixNBduqgY5SudnOt nQGq9SZHYY3VCZyO4d1U3rhPP1LFyHTkDA06AwDMV9I2jImA/I2Vofqy3ORWjBUZ ZF7xGiZ3jWuEOGhtyESTDYkfRIxir1zQKywb/1p+21f2lVFx+wc= =QsUe -----END PGP SIGNATURE----- --x7HUe2JbQ8ROazkf--