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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48B4BC433EF for ; Tue, 22 Feb 2022 20:31:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235484AbiBVUbj (ORCPT ); Tue, 22 Feb 2022 15:31:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231694AbiBVUbh (ORCPT ); Tue, 22 Feb 2022 15:31:37 -0500 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25D1613CEFF for ; Tue, 22 Feb 2022 12:31:10 -0800 (PST) Received: (Authenticated sender: alexandre.belloni@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 25F99C0006; Tue, 22 Feb 2022 20:31:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1645561868; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FtuFfP7bf62RQnyfTs94b0RuonH4es1pIRqKW4UPqno=; b=KCS9BQw4EXM0r3F6Qy8PQwVvNQ7vVbSfScLUDd5qlj9L6xFHzNeMytBYDdtUjLp+NLf/7D eB8BUUvhuSGyVXvKMYFZ4QS3U3H8wlPwnad/Rdab87Tm7xHx7TpJsbvZsqPsDHwT/txt2Q 8ke/vmD66aEzhetPa3uJ3NfiVR0rzVGNBjb9Vnv2x7dwHTQjMZbe0G7uQevL2YGrwzMl8J K/467CqeyGs/wzEZ0k3pq+5VH7LiKpGrLu9YgDIVwkExgTBBWGbxi6emu/tEfmHRLVobpM ovVFE8ZsZ+mQfrW3VnYXDnwA189qF6QshKy8Ou/MaMCoTs2dxbbwSSPSmWmxcQ== Date: Tue, 22 Feb 2022 21:31:03 +0100 From: Alexandre Belloni To: Andrew Lunn Cc: =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , Andy Shevchenko , Daniel Scally , Heikki Krogerus , Sakari Ailus , Greg Kroah-Hartman , "Rafael J . Wysocki" , Wolfram Sang , Peter Rosin , Russell King , Heiner Kallweit , "David S . Miller" , Jakub Kicinski , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-i2c@vger.kernel.org, netdev@vger.kernel.org, Thomas Petazzoni Subject: Re: [RFC 09/10] i2c: mux: add support for fwnode Message-ID: References: <20220221162652.103834-1-clement.leger@bootlin.com> <20220221162652.103834-10-clement.leger@bootlin.com> <20220222095325.52419021@fixe.home> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/02/2022 11:57:39+0100, Andrew Lunn wrote: > On Tue, Feb 22, 2022 at 09:53:25AM +0100, Clément Léger wrote: > > Le Mon, 21 Feb 2022 19:55:25 +0200, > > Andy Shevchenko a écrit : > > > > > On Mon, Feb 21, 2022 at 05:26:51PM +0100, Clément Léger wrote: > > > > Modify i2c_mux_add_adapter() to use with fwnode API to allow creating > > > > mux adapters with fwnode based devices. This allows to have a node > > > > independent support for i2c muxes. > > > > > > I^2C muxes have their own description for DT and ACPI platforms, I'm not sure > > > swnode should be used here at all. Just upload a corresponding SSDT overlay or > > > DT overlay depending on the platform. Can it be achieved? > > > > > > > Problem is that this PCIe card can be plugged either in a X86 platform > > using ACPI or on a ARM one with device-tree. So it means I should have > > two "identical" descriptions for each platforms. > > ACPI != DT. > > I know people like stuffing DT properties into ACPI tables, when ACPI > does not have a binding. But in this case, there is a well defined > ACPI mechanism for I2C muxes. You cannot ignore it because it is > different to DT. So you need to handle the muxes in both the ACPI way > and the DT way. > > For other parts of what you are doing, you might be able to get away > by just stuffing DT properties into ACPI tables. But that is not for > me to decide, that is up to the ACPI maintainers. > What I'm wondering is why you would have to stuff anything in ACPI when plugging any PCIe card in a PC. Wouldn't that be a first? I don't have to do so when plugging an Intel network card, I don't expect to have to do it when plugging any other network card... -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com