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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 6B203C433DB for ; Thu, 18 Mar 2021 14:53:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 36F8464E22 for ; Thu, 18 Mar 2021 14:53:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229508AbhCROxL (ORCPT ); Thu, 18 Mar 2021 10:53:11 -0400 Received: from mout.kundenserver.de ([212.227.17.10]:45855 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231273AbhCROxB (ORCPT ); Thu, 18 Mar 2021 10:53:01 -0400 Received: from mail-ot1-f48.google.com ([209.85.210.48]) by mrelayeu.kundenserver.de (mreue108 [213.165.67.113]) with ESMTPSA (Nemesis) id 1Mq2rM-1m04bJ1vSE-00nBDX; Thu, 18 Mar 2021 15:52:59 +0100 Received: by mail-ot1-f48.google.com with SMTP id g8-20020a9d6c480000b02901b65ca2432cso5433828otq.3; Thu, 18 Mar 2021 07:52:59 -0700 (PDT) X-Gm-Message-State: AOAM531HbNfmnq5vAvA7q78ifwUFH/gJA+BFQuxSvclZwSEntC340J6K qOGijfYkxNBdwNU6UcqOfzAe9p2ydjEdsJhFqjg= X-Google-Smtp-Source: ABdhPJw7Eug2yd9ucu2dKZlBIqyoyljV2ZH8YZeMrPCW0lZjBwbRWIkmu8XcOw0kOzzkDzHjb1kP6HgcXNEyY4KVhCY= X-Received: by 2002:a05:6830:14c1:: with SMTP id t1mr7894612otq.305.1616079178056; Thu, 18 Mar 2021 07:52:58 -0700 (PDT) MIME-Version: 1.0 References: <20210316074409.2afwsaeqxuwvj7bd@vireshk-i7> <0dfff1ac-50bb-b5bc-72ea-880fd52ed60d@metux.net> In-Reply-To: <0dfff1ac-50bb-b5bc-72ea-880fd52ed60d@metux.net> From: Arnd Bergmann Date: Thu, 18 Mar 2021 15:52:41 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v8] i2c: virtio: add a virtio i2c frontend driver To: "Enrico Weigelt, metux IT consult" Cc: Viresh Kumar , Jie Deng , Linux I2C , virtualization@lists.linux-foundation.org, Linux Kernel Mailing List , "Michael S. Tsirkin" , Wolfram Sang , Jason Wang , Wolfram Sang , Andy Shevchenko , conghui.chen@intel.com, kblaiech@mellanox.com, jarkko.nikula@linux.intel.com, Sergey Semin , Mike Rapoport , loic.poulain@linaro.org, Tali Perry , =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , Bjorn Andersson , yu1.wang@intel.com, shuo.a.liu@intel.com, Stefan Hajnoczi , Paolo Bonzini Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:TM47QfXkzV/u9lf8AsYQUq4wdOsnNc7RRaPHIqMtC515cOaRb9i XMO9RebAJooP4D3kava4yxzf9rSprx1EHvk2xUM6XQxhPqpZO3QjJO5QjD53c6EXPK0W+2J vGe9gyy66HBbfx0vLHsque9Y/WnXB2V3GXZmyPqjsuGhiHrJvV81z/9RYRyWyBATuisssOJ Ft6ruV+GVmcuVVu7OeDRA== X-UI-Out-Filterresults: notjunk:1;V03:K0:b5kOYfQE5AU=:XkLS+KRh7WuI5Iu7S+55bs +l/MXVyDZElm0C4Hlp2mzHbvGWJ11tGF7XANrv6YLxQmidi1Y/9kSYCuLZlKeflX7Ryo/vhmn stw+5NdrKQgw/YNGRGh+279MXKPl04mPybOA15oIPPzI0JkzJ7wImUlreYpXnotzIMu7vM0qT 1/Ja8LLEJB+KMPWt3Tea3MmJ7BQoa3BhJJvEbAGh+698KHqh8kCSBTluOIkwpCLTRr/b4PnOB qdX4XDzH1klANFcZLxT5FwVoic8Dld6VBNiHnmdW6BbJyfI/P0ebRa+sBar8GBNHgB3xbwMs5 y27T4cgCScfSKbv/jzlBQcVIu/bKea2s9zEurZiPCy0kme875XtOgkIvaVITxj2JMXBuV+D0X zX6F7Z9iZGj3V9n/UOm52lkwZFF2RB18sGcPBamwy9FtdXphgR3c1iMHnCcl5lZNDg4RDdvWc jGsN2F/HM+dM+HPb0gLa6mUFJnWTxxqeTGs0hw6ZsCfdVPOM2gzVmMgyAb3Zaknxme4aGeDkR xNuQ730BKYLT8a6cKoM12BvqItldefp4tR6oMKw09whnLNYDUywNgYSMNizVknRsQ== Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On Thu, Mar 18, 2021 at 3:42 PM Enrico Weigelt, metux IT consult wrote: > > On 16.03.21 08:44, Viresh Kumar wrote: > > > FWIW, this limits this driver to support a single device ever. We > > can't bind multiple devices to this driver now. Yeah, perhaps we will > > never be required to do so, but who knows. > > Actually, I believe multiple devices really should be possible. > > The major benefit of virtio-i2c is either bridging certan real bus'es > into a confined workload, or creating virtual hw testbeds w/o having to > write a complete emulation (in this case, for dozens of different i2c > controllers) - and having multiple i2c interfaces in one machine isn't > exactly rare. Allowing multiple virtio-i2c controllers in one system, and multiple i2c devices attached to each controller is clearly something that has to work. I don't actually see a limitation though. Viresh, what is the problem you see for having multiple controllers? Arnd