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 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 862D0C2D0A8 for ; Wed, 23 Sep 2020 19:48:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 429FC20888 for ; Wed, 23 Sep 2020 19:48:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726460AbgIWTsf (ORCPT ); Wed, 23 Sep 2020 15:48:35 -0400 Received: from mout.kundenserver.de ([212.227.126.135]:53751 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726381AbgIWTse (ORCPT ); Wed, 23 Sep 2020 15:48:34 -0400 X-Greylist: delayed 304 seconds by postgrey-1.27 at vger.kernel.org; Wed, 23 Sep 2020 15:48:34 EDT Received: from mail-qk1-f172.google.com ([209.85.222.172]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.129]) with ESMTPSA (Nemesis) id 1MPK73-1k6gbE2KXV-00PZmn; Wed, 23 Sep 2020 21:43:29 +0200 Received: by mail-qk1-f172.google.com with SMTP id 16so950714qkf.4; Wed, 23 Sep 2020 12:43:29 -0700 (PDT) X-Gm-Message-State: AOAM531k+6cFCGvKlq9ZOn/bJk0PW5wC1hdxDa2ZeBc6uZC1UfC14jVB Sl488IehFXiaXiq5kGymroovDMzjMhrSk5O4dOY= X-Google-Smtp-Source: ABdhPJyn6PBTLIZkNftTyKRiHCSe0jnGHmRoh0ig+i/aHp9NtN97mSHMr09kiJcYqk0qSH8c8idO3VOG5Tt00K+/tlE= X-Received: by 2002:a05:620a:15a7:: with SMTP id f7mr1426063qkk.3.1600890208253; Wed, 23 Sep 2020 12:43:28 -0700 (PDT) MIME-Version: 1.0 References: <20200923151511.3842150-1-luzmaximilian@gmail.com> In-Reply-To: From: Arnd Bergmann Date: Wed, 23 Sep 2020 21:43:12 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH 0/9] Add support for Microsoft Surface System Aggregator Module To: Maximilian Luz Cc: "linux-kernel@vger.kernel.org" , linux-serial@vger.kernel.org, ACPI Devel Maling List , Greg Kroah-Hartman , Rob Herring , Jiri Slaby , "Rafael J. Wysocki" , Len Brown , =?UTF-8?Q?Bla=C5=BE_Hrastnik?= , Dorian Stoll Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:W2KZH/f7lez05WWj13E5feQrfDbh6fkDJF0vlt8lZht4NgLOyA0 Z3jZXxBurib5D93Qv2fogLSqyYlEAOfU5wwbWcms4STgpwIPxwCd701gQ6Xld1Z6zTI0nVK 3Rui5mraoL4pUNa192amiED+z7nrtv5E5m5s+82Ljui3AmsV9jZq/rX7JdE5NB/SdWCDLta SbXfNb0coQ1FOfPs+xZ2A== X-UI-Out-Filterresults: notjunk:1;V03:K0:sLsSeXvckVs=:EsiTAwKr3Sfttf0XpxaUW8 ApnkyAsScsHVin/McCNWTOVwZJUf3GzhpzoPMATXjqB0w3ikVKlYaKeGiVP4rhLdUgZy+m8Lg CbSTUXcNZ5S6zA41mZe1WhSB/hk0FGv2lmLccYnjVsSQXBlWImRWi7LzzF4gq52FUK3s0aeuz 50c+WlfzWL8tY7Qm+Kw21otQ2F+xEZtC+VQkSBWWiV2M3Nm+HDklKuDms0KF3Y+yd/goXWEn6 o9NPZpviBG/F4niZXDtsvu6BSQZh4huq46xXQEfUvvkMBYxx0mNOPyjFsPTGLeeQ54B9z1lbF bhz16gdOm90HLnI37L8HTLeg3Km5+pj17+s9IUWvxK6tVJmZt6MNMzxNGSTmIBugtt8LUfft5 jFJEAH7LKVrnNmlowzsdwgaKc3zmSic4hg2TkvNnhdwguotLgjp3OfpHOYLOC/LVTQWrgBMmo pRhV/hp59JEGQM4F9lB+c7DyICbEjMnCxYnQ4Ez8DbO4u5TRc1LFQpvbtsQLbgQFQ+DiBk66A FyQnGV6eGIMiS2Zq60EZ9i8tIIvtqxKa6jcQY9uq/tlhAeq5tWu1D2wXx6Hs3+m63umV6V/M4 tsJrdjX+69N5gI1gIUIUZAk+kkw/1UUmiJLh+RfhPQ+vkJ7B5BHEuCxgANW9K0QLmDeZisCtQ pS2jnDFBECgz2Bnaxjv8HQac8sYrhDGwgYs8n2mRsU+ATkgieAHrbivzDdKqV2XLntza9hqse fqzYOA+sQFAcY2yyCxoPJ3mqzScUa+DO2aYzFKwtyBV623SqRQ2TH37vFfbZVRcRwq1kFXuun vDFjUKWOEiLOy685vAuthBFnZjtT/tSSZtdDQD4i8xkNXayRV0dSC6/fyUL7MeiYkcI5zQ/Mw wjEsGzoJJH03rFj3jFgRAje5LLYmOb3DvGF/TqibWicrb+o32S1lY711mHj5243CxEoy3VbJU MrX3iWIbG6sWSx8weWQTxqzggkQk2fyMJm3147yX8F4Ipq8yaGRoJ Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Wed, Sep 23, 2020 at 5:43 PM Maximilian Luz wrote: > > On 9/23/20 5:30 PM, Arnd Bergmann wrote: > > On Wed, Sep 23, 2020 at 5:15 PM Maximilian Luz wrote: > >> > >> Hello, > >> > >> The Surface System Aggregator Module (we'll refer to it as Surface > >> Aggregator or SAM below) is an embedded controller (EC) found on various > >> Microsoft Surface devices. Specifically, all 4th and later generation > >> Surface devices, i.e. Surface Pro 4, Surface Book 1 and later, with the > >> exception of the Surface Go series and the Surface Duo. Notably, it > >> seems like this EC can also be found on the ARM-based Surface Pro X [1]. > > > > I think this should go to drivers/platform/x86 or drivers/platform/surface/ > > along with other laptop vendor specific code rather than drivers/misc/. > > I initially had this under drivers/platform/x86. There are two main > reasons I changed that: First, I think it's a bit too big for > platform/x86 given that it basically introduces a new subsystem. At this > point it's really less of "a couple of odd devices here and there" and > more of a bus-type thing. Second, with the possibility of future support > for ARM devices (Pro X, Pro X 2 which is rumored to come out soon), I > thought that platform/x86 would not be a good fit. I don't see that as a strong reason against it. As you write yourself, the driver won't work on the arm machines without major changes anyway, and even if it does, it fits much better with the rest of it. If you are worried about the size of the directory, drivers/platform/x86/surface/ would also work. > I'd be happy to move this to platform/surface though, if that's > considered a better fit and you're okay with me adding that. Would make > sense given that there's already a platform/chrome, which, as far as I > can tell, also seems to be mainly focused on EC support. Yes, I think the main question is how much overlap you see functionally between this driver and the others in drivers/platform/x86. Arnd