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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 26823C432C0 for ; Tue, 19 Nov 2019 16:08:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 077B122365 for ; Tue, 19 Nov 2019 16:08:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728317AbfKSQIQ (ORCPT ); Tue, 19 Nov 2019 11:08:16 -0500 Received: from mga17.intel.com ([192.55.52.151]:57742 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727509AbfKSQIQ (ORCPT ); Tue, 19 Nov 2019 11:08:16 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Nov 2019 08:07:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,218,1571727600"; d="scan'208";a="215567147" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.163]) by fmsmga001.fm.intel.com with SMTP; 19 Nov 2019 08:07:57 -0800 Received: by lahna (sSMTP sendmail emulation); Tue, 19 Nov 2019 18:07:56 +0200 Date: Tue, 19 Nov 2019 18:07:56 +0200 From: Mika Westerberg To: Hans de Goede Cc: Andy Shevchenko , "Rafael J . Wysocki" , Len Brown , linux-gpio@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH] ACPI / button: Add DMI quirk for Acer Switch 10 SW5-032 lid-switch Message-ID: <20191119160756.GL11621@lahna.fi.intel.com> References: <20191118153556.28751-1-hdegoede@redhat.com> <20191119082642.GF11621@lahna.fi.intel.com> <7a2ac981-1c28-5abb-0599-68da44675bdc@redhat.com> <20191119124411.GF32742@smile.fi.intel.com> <20191119125757.GJ11621@lahna.fi.intel.com> <84e0ce18-500e-b45a-c77a-ad4cc35b1533@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <84e0ce18-500e-b45a-c77a-ad4cc35b1533@redhat.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Tue, Nov 19, 2019 at 04:38:52PM +0100, Hans de Goede wrote: > Hi, > > On 19-11-2019 13:57, Mika Westerberg wrote: > > On Tue, Nov 19, 2019 at 02:44:11PM +0200, Andy Shevchenko wrote: > > > On Tue, Nov 19, 2019 at 12:12:35PM +0100, Hans de Goede wrote: > > > > On 19-11-2019 09:26, Mika Westerberg wrote: > > > > > On Mon, Nov 18, 2019 at 04:35:56PM +0100, Hans de Goede wrote: > > > > > > > Working around this is not impossible, but it will be quite ugly and given > > > > the age of the machine IMHO not worth it. I've also found out that I need a > > > > DSDT override to be able to control the LCD backlight, this is controlled by > > > > the 1st PWM controller in the SoC LPSS block, which is normally enumerated > > > > through ACPI but the entire Device (PWM1) {} block is missing from the > > > > DSDT :| Adding it from similar hardware fixes things and makes the backlight > > > > controllable. TL;DR: it seems that this is one of the rare cased where > > > > people who want to run Linux will need to do a manual DSDT override :| > > > > > > If it's missing it's easy to inject entire block from EFI variable or using > > > ConfigFS (see meta-acpi project [1] for details). > > > > > > > When they do that override they can also fix the _LID method and > > > > then re-enable LID functionality on the kernel commandline overriding > > > > this DMI quirk. > > > > > > Yes, if you override entire DSDT it can be fixed for many bugs at once. > > > > > > > I will probably do a blog post on this (some people have asked me > > > > to do some blogposts about how to analyze DSDT-s, this will be a nice > > > > example) and add a link to the DSDT override to the blogpost, I believe > > > > that this is the best we can do for users of this device. > > > > > > Perhaps above mentioned project somehow can be extended to keep DSDT ASL code > > > for overriding? Mika? > > > > > > [1]: https://github.com/westeri/meta-acpi/ > > > > No objections. > > > > Maybe we should have a mechanism in the kernel that allows you to have > > ACPI table quirks like this for multiple different systems (based on DMI > > indentifiers perhaps) inside a single initrd and the kernel then loads > > tables only matching the running system. That would allow distros to > > ship these for broken systems. > > I would love to have something like this, but I'm afraid that the distros > cannot just distribute modified DSDT's. I know we ask people to upload > acpidump's to bugzilla, etc. all the time. But one can reasonably argue > that that is fair-use (IANAL, TINLA). OTOH for something to be distributed > by distros we are going to need something a lot less handwavy wrt > re-dsitribution of these files, which AFAIK is impossible to get. Good point. > I had a discussion about this a while ago at my local hackerspace (*), > and someone there suggested to distribute patch files and have some > scripts which automatically generate an overlay by doing acpidump + > acpixtract + iasl -d + apply-patch + iasl -ta. This would then automatically > run at boot so that the next boot will have a fixed DSDT. Which is an > interesting concept if anyone is willing to work on it ... Indeed interesting idea. Not volunteering to work on it though ;-)