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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 CBB8FC433DB for ; Wed, 17 Mar 2021 07:08:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93E9A64F9F for ; Wed, 17 Mar 2021 07:08:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229505AbhCQHI0 (ORCPT ); Wed, 17 Mar 2021 03:08:26 -0400 Received: from lizzard.sbs.de ([194.138.37.39]:52630 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229472AbhCQHH7 (ORCPT ); Wed, 17 Mar 2021 03:07:59 -0400 Received: from mail2.sbs.de (mail2.sbs.de [192.129.41.66]) by lizzard.sbs.de (8.15.2/8.15.2) with ESMTPS id 12H77lLO019222 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 17 Mar 2021 08:07:47 +0100 Received: from [167.87.41.130] ([167.87.41.130]) by mail2.sbs.de (8.15.2/8.15.2) with ESMTP id 12H6vja0026646; Wed, 17 Mar 2021 07:57:46 +0100 Subject: Re: [PATCH v4 2/2] gpio: sch: Hook into ACPI SCI handler to catch GPIO edge events To: Andy Shevchenko , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Andy Shevchenko , Linus Walleij , Bartosz Golaszewski References: <20210316162613.87710-1-andriy.shevchenko@linux.intel.com> <20210316162613.87710-3-andriy.shevchenko@linux.intel.com> From: Jan Kiszka Message-ID: Date: Wed, 17 Mar 2021 07:57:44 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16.03.21 21:49, Andy Shevchenko wrote: > On Tue, Mar 16, 2021 at 06:26:13PM +0200, Andy Shevchenko wrote: >> From: Jan Kiszka >> >> Neither the ACPI description on the Quark platform provides the required >> information is to do establish generic handling nor hardware capable of >> doing it. According to the datasheet the hardware can generate SCI events. >> Therefore, we need to hook from the driver directly into SCI handler of >> the ACPI subsystem in order to catch and report GPIO-related events. >> >> Validated on the Quark-based IOT2000 platform. > > This patch must be dropped completely. SCI handler is not correct way to do > this. The proper way (and we have already few examples in the kernel) is to > register GPE event. As explained above, this is not supported by the preexisting firmware, and there won't be any updates to it anymore. This platform is history, the SoC was discontinued by Intel long ago, and our devices reaching their support end as well. The race to upstream was lost in this case - backlog too long, we being too slow. Jan > > It took me a while to gather all bits of this puzzle. > > At least now I get an event, but kernel oopses, I'll continue debugging > tomorrow. > -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux