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 EFAF5C11F68 for ; Fri, 2 Jul 2021 06:22:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D703E613F9 for ; Fri, 2 Jul 2021 06:22:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230104AbhGBGY4 (ORCPT ); Fri, 2 Jul 2021 02:24:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:39816 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbhGBGYy (ORCPT ); Fri, 2 Jul 2021 02:24:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2CC21613FA; Fri, 2 Jul 2021 06:22:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625206942; bh=+9+44rB/9RcT9+DjjfGfMY5WQvks+ySXpU6PeYPkon8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=M/LH+b3HktzFxuCnvsn3c2hWtGMNr9OFVVf/CE62QY3EBrcR30BOuPLaxvu3ikg/J CxWFeP//q3nmIoe+uXo2Q5ysxpOYzo55/Xj9kIbSDyS1DtaI3U9WObsZd9V098hjb8 AlwEFtYDxR7/rvSzBJGOd5+z3CHz81LovwyuWyOZwqdut3F7t9jonhKyu8ROWkt6SP DrRjemMKFdJHoy+eqGbzU7Sc8PbYIwz24CS1DqoX9sRsx7vdOMDqsoayeesLyyFPT/ 4qTh7stU2NyGSBc4vhPmKUHmjVBuR7l1o+EzunE5HHd5xQudWbYlIZ3ai3OH3jm+Hm dGa3thQkyegCQ== Date: Fri, 2 Jul 2021 08:22:13 +0200 From: Wolfram Sang To: Viresh Kumar Cc: Jie Deng , linux-i2c@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, mst@redhat.com, arnd@arndb.de, jasowang@redhat.com, andriy.shevchenko@linux.intel.com, yu1.wang@intel.com, shuo.a.liu@intel.com, conghui.chen@intel.com, stefanha@redhat.com Subject: Re: [PATCH v11] i2c: virtio: add a virtio i2c frontend driver Message-ID: Mail-Followup-To: Wolfram Sang , Viresh Kumar , Jie Deng , linux-i2c@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, mst@redhat.com, arnd@arndb.de, jasowang@redhat.com, andriy.shevchenko@linux.intel.com, yu1.wang@intel.com, shuo.a.liu@intel.com, conghui.chen@intel.com, stefanha@redhat.com References: <510c876952efa693339ab0d6cc78ba7be9ef6897.1625104206.git.jie.deng@intel.com> <20210701040436.p7kega6rzeqz5tlm@vireshk-i7> <20210702045512.u4dvbapoc5a2a4jb@vireshk-i7> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="SotEO4qp2V5IcJ53" Content-Disposition: inline In-Reply-To: <20210702045512.u4dvbapoc5a2a4jb@vireshk-i7> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --SotEO4qp2V5IcJ53 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > > Wolfram, what's expected here ? Shouldn't all message transfer or > > > none? > >=20 > > Well, on a physical bus, it can simply happen that after message 3 of 5, > > the bus is stalled, so we need to bail out. >=20 > Right, and in that case the transfer will have any meaning left? I believ= e it > needs to be fully retried as the requests may have been dependent on each= other. The client driver handles the case. I'd assume most will bail out of the calling function and at some higher level it will be retried. > > Of course, it can later happen on the physical bus of the host, though, > > that the bus is stalled after message 3 of 5, and I2C_RDWR will bail > > out. >=20 > Basically we fail as soon as we know something is not right, correct? Yes. --SotEO4qp2V5IcJ53 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmDesJEACgkQFA3kzBSg KbZOhQ/+NdCmNPinhpL6SdKc6r1zoX7a8w6FmzzQqKowP11lIlFQrnYz4gdlCWiQ c7auvFAY3ExcnZsxclZIfjuW5GEBV1W2QVx6i3Uk7GUqAUPb34L6mcmBqDZY6PyL Mw8TbpZBq5PegAW5c39YYCfeuLe3hotMYvxrTciwghhZb9ikqlGmKeP9hkx9EfRD ZCGfaiMFUiwBYqHZtf36E5fuVipLuu8FNUVInqeCmpZYY1eCAeAeQXh+T7GDPVLe N15pQjoFftokmAksoakfgSFr2B6QXrLkaIrxv2bi6FnhfFRp9Kei+2H7vV9q23hT kH5YYhyCi5kN85TM9NOXd7JFgSDZBt0yEE+0uEmOa7oFDz8m8jGW8hB1rc0PiY2M bY6XAwNaUsBwtNOZHTr/eSCQcwaU3disNJfft27QfaZrudsY2+6K5Igh5sOfGUiH 7rsomHl6sp4FL2oEzqYzsiPSurtgulbwpZEh53wKDpL75AxAR/+tfS+u410Wpoie jQUHV5ndqrW9z2P0Y4Qvea0Fd/PvIepAqSUnXVRXMqxpDzY3zQwSN/NgJNARKDWo FZnbWSjaO0gNIUjMLra3vOdbrkLxQ3Moayzol0/KgWdDyIuQQpKKnzfG0fq86fda yZRPQCwNhdeKoXvwRA4wpZ2i3btTeovkMCWdTdwtBeO1R8L9vfg= =vze1 -----END PGP SIGNATURE----- --SotEO4qp2V5IcJ53--