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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 460F9C48BE8 for ; Fri, 18 Jun 2021 09:14:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2236561175 for ; Fri, 18 Jun 2021 09:14:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232256AbhFRJQV (ORCPT ); Fri, 18 Jun 2021 05:16:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231441AbhFRJQU (ORCPT ); Fri, 18 Jun 2021 05:16:20 -0400 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2A4AC06175F for ; Fri, 18 Jun 2021 02:14:10 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id d13so13023168ljg.12 for ; Fri, 18 Jun 2021 02:14:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=fk/g4Uf4e6ndK9NTLJ4fya67I6nyHsWdWmINzLkYxxQ=; b=Ej/kae+4z4muiWg6EWVSQJZ0hKf207pahpJvxNxI5rzvReNLTOakQyMu0hPKFKQapC KdfIPU1/IY5qQj8piocGrYiAvwhAsKgD6Aac0EfK5OBIgHBnb0t9I5fWbElLuPl9j7uG f8EsIa72iX68DlTtcVZ2ZytW6itc2zcRTL2NmByb6VBTT/40OIdIokHxEx3crUwnaeej do28bIC90BwWHOqkQQANMqlKuQAUvGklT9o4LJ+nOW/mFuWiHSGCUkSA0RXj+USUl5Zu gL+aEhP1YsJsUvXvI7EYMZVd4VlDwDMgbNhmdQLYBjLy9adLLvADaViX2g39cl3yZ8oY AMCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=fk/g4Uf4e6ndK9NTLJ4fya67I6nyHsWdWmINzLkYxxQ=; b=IJGOfY8S7zx9gbX1otwkeijganEG5wdLAvWSsZhsINXFh1Z7BfQeR36i9ecRkXhCcM Cg+CcsJhH5RUnunkGjATSudxl6LNCtDHFdGhe5BoTAAEOBGGw5be9l3wDQIHG2VzZAol LGVgUNzQKzUyS78usObtG943bhbI2lBcgEHZWR5nZBr0MpZZW/D8a+xH5FJnsdUzGCOV yHNEi2GyM2tPZ3N+ahoDWeUWaVAmTypu2d7kMzdMkM7UMba6TH1S9I8FPUtzSK/EwVYq CZEDZeoerSlESTqbFbt9ar3pZHYTsCZo6xQtGutdVHz+I3vIksD3vWf/EQoZ3vcM5Zd4 8Oow== X-Gm-Message-State: AOAM531EHjH14wnJa03N4KYZUIpoUQ+zb1iRkXJGF04oHcTsII3Prws4 68ZkouulO4LrDFLFCV8tUdLkhtDVNEw6OPKUXhI9mw== X-Google-Smtp-Source: ABdhPJxO5angft3VVWPEspBXdSa1jj492/Lqu/sjYy6Szkm5Bb7VcFbM7lZNp02NJxKP3yiLMp83/cpYtRf0ZvPmzDg= X-Received: by 2002:a2e:95d8:: with SMTP id y24mr2468745ljh.368.1624007648913; Fri, 18 Jun 2021 02:14:08 -0700 (PDT) MIME-Version: 1.0 References: <10442926ae8a65f716bfc23f32339a6b35e51d5a.1623326176.git.viresh.kumar@linaro.org> <8d58da79-8e54-048b-db89-8c1caaa0320f@metux.net> In-Reply-To: <8d58da79-8e54-048b-db89-8c1caaa0320f@metux.net> From: Linus Walleij Date: Fri, 18 Jun 2021 11:13:57 +0200 Message-ID: Subject: Re: [PATCH V3 1/3] gpio: Add virtio-gpio driver To: "Enrico Weigelt, metux IT consult" Cc: Bjorn Andersson , Viresh Kumar , Geert Uytterhoeven , Bartosz Golaszewski , "Enrico Weigelt, metux IT consult" , Viresh Kumar , "Michael S. Tsirkin" , Jason Wang , Vincent Guittot , Bill Mills , "Alex Benn?e" , stratos-dev@op-lists.linaro.org, "open list:GPIO SUBSYSTEM" , linux-kernel , Stefan Hajnoczi , "Stefano Garzarella --cc virtualization @ lists . linux-foundation . org" , virtualization@lists.linux-foundation.org, Alistair Strachan Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Wed, Jun 16, 2021 at 5:52 PM Enrico Weigelt, metux IT consult wrote: > On 16.06.21 05:30, Bjorn Andersson wrote: > > > Combined with the virtio-i2c effort this could provide an alternative by > > simply tunneling the busses and GPIOs into Linux and use standard iio > > drivers, for cases where this suits your product requirements better. > > So, you wanna use virtio as logical interface between the two CPUs ? > Interesting idea. Usually folks use rpmsg for those things. rpmsg is using shared memory as transport mechanism and virtio is providing this. rpmsg is conceptually a child of virtio: when the subsystem was proposed by TI Arnd noted that virtio has large similarities in shared memory transport and as the potential reuse for buffer handling etc was excellent virtio was used as a base for rpmsg/remoteproc work. Yours, Linus Walleij 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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 5D935C49361 for ; Fri, 18 Jun 2021 09:14:15 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 05119613E9 for ; Fri, 18 Jun 2021 09:14:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05119613E9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id B808F403C7; Fri, 18 Jun 2021 09:14:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id H2n197h06Q0M; Fri, 18 Jun 2021 09:14:13 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id 2E84B403F8; Fri, 18 Jun 2021 09:14:13 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id D61ECC000D; Fri, 18 Jun 2021 09:14:12 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 10DCCC000B for ; Fri, 18 Jun 2021 09:14:12 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 0CDD683AC3 for ; Fri, 18 Jun 2021 09:14:12 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp1.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=linaro.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id iV7bs58gAIPs for ; Fri, 18 Jun 2021 09:14:11 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.8.0 Received: from mail-lj1-x230.google.com (mail-lj1-x230.google.com [IPv6:2a00:1450:4864:20::230]) by smtp1.osuosl.org (Postfix) with ESMTPS id 1315F83ABB for ; Fri, 18 Jun 2021 09:14:10 +0000 (UTC) Received: by mail-lj1-x230.google.com with SMTP id q23so2610178ljh.0 for ; Fri, 18 Jun 2021 02:14:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=fk/g4Uf4e6ndK9NTLJ4fya67I6nyHsWdWmINzLkYxxQ=; b=Ej/kae+4z4muiWg6EWVSQJZ0hKf207pahpJvxNxI5rzvReNLTOakQyMu0hPKFKQapC KdfIPU1/IY5qQj8piocGrYiAvwhAsKgD6Aac0EfK5OBIgHBnb0t9I5fWbElLuPl9j7uG f8EsIa72iX68DlTtcVZ2ZytW6itc2zcRTL2NmByb6VBTT/40OIdIokHxEx3crUwnaeej do28bIC90BwWHOqkQQANMqlKuQAUvGklT9o4LJ+nOW/mFuWiHSGCUkSA0RXj+USUl5Zu gL+aEhP1YsJsUvXvI7EYMZVd4VlDwDMgbNhmdQLYBjLy9adLLvADaViX2g39cl3yZ8oY AMCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=fk/g4Uf4e6ndK9NTLJ4fya67I6nyHsWdWmINzLkYxxQ=; b=QTyrppBmVCB7vOt1sIBZ0cG0XiUqcOBBWwEDITCFJ2zbWfDdqpUUmIMsaHdAAl4Es+ bHbXuRRePsjBOF7gcMx929ngeCGuGsKiqbvIAnV00f0XAHA83Y7lcxalHhtyRbvSWkAN idLnbqD/9/ZxoQVqDZxofvT0YfxnT+i5q+EHdrxGD8TyWhx8r9Up2uNPKnSraXL0PAuT wlQ2kTGreESHfNcqjqks7Mk9h7Bij6GJR1bZGUw4+ar4JIBhCgM7ADarIVmGhTR6OPrr sWzLd1oEg6zejUXgE0NnD9T6dreL9rRFmhE9+PTmBjs3kb+2AP0Ws0qCU18keyz0O7Uj ST1A== X-Gm-Message-State: AOAM531dQoOSSuRB+FWzmPtFgvFRE23LliDz+4iLmiDCJ9ObfJo/nYNt NugB3hsv6TnYiMKizfEmLGzj16A/Cp5SioW+Uwm7Hg== X-Google-Smtp-Source: ABdhPJxO5angft3VVWPEspBXdSa1jj492/Lqu/sjYy6Szkm5Bb7VcFbM7lZNp02NJxKP3yiLMp83/cpYtRf0ZvPmzDg= X-Received: by 2002:a2e:95d8:: with SMTP id y24mr2468745ljh.368.1624007648913; Fri, 18 Jun 2021 02:14:08 -0700 (PDT) MIME-Version: 1.0 References: <10442926ae8a65f716bfc23f32339a6b35e51d5a.1623326176.git.viresh.kumar@linaro.org> <8d58da79-8e54-048b-db89-8c1caaa0320f@metux.net> In-Reply-To: <8d58da79-8e54-048b-db89-8c1caaa0320f@metux.net> From: Linus Walleij Date: Fri, 18 Jun 2021 11:13:57 +0200 Message-ID: Subject: Re: [PATCH V3 1/3] gpio: Add virtio-gpio driver To: "Enrico Weigelt, metux IT consult" Cc: Alistair Strachan , Vincent Guittot , Stefan Hajnoczi , Geert Uytterhoeven , "Michael S. Tsirkin" , Viresh Kumar , virtualization@lists.linux-foundation.org, linux-kernel , Bjorn Andersson , Bartosz Golaszewski , "open list:GPIO SUBSYSTEM" , Viresh Kumar , "Enrico Weigelt, metux IT consult" , Bill Mills , stratos-dev@op-lists.linaro.org X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Wed, Jun 16, 2021 at 5:52 PM Enrico Weigelt, metux IT consult wrote: > On 16.06.21 05:30, Bjorn Andersson wrote: > > > Combined with the virtio-i2c effort this could provide an alternative by > > simply tunneling the busses and GPIOs into Linux and use standard iio > > drivers, for cases where this suits your product requirements better. > > So, you wanna use virtio as logical interface between the two CPUs ? > Interesting idea. Usually folks use rpmsg for those things. rpmsg is using shared memory as transport mechanism and virtio is providing this. rpmsg is conceptually a child of virtio: when the subsystem was proposed by TI Arnd noted that virtio has large similarities in shared memory transport and as the potential reuse for buffer handling etc was excellent virtio was used as a base for rpmsg/remoteproc work. Yours, Linus Walleij _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization