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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 DF79DC6778A for ; Sat, 7 Jul 2018 23:37:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D287208B1 for ; Sat, 7 Jul 2018 23:37:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D287208B1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754462AbeGGXhz (ORCPT ); Sat, 7 Jul 2018 19:37:55 -0400 Received: from mga14.intel.com ([192.55.52.115]:25924 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754352AbeGGXhx (ORCPT ); Sat, 7 Jul 2018 19:37:53 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Jul 2018 16:37:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,322,1526367600"; d="scan'208";a="69491044" Received: from spandruv-mobl.amr.corp.intel.com ([10.254.118.97]) by fmsmga004.fm.intel.com with ESMTP; 07 Jul 2018 16:37:52 -0700 Message-ID: <82968804b607bf33550ba6fbaebc658db3953804.camel@linux.intel.com> Subject: Re: [PATCH v2] platform/x86: intel-hid: Add support for Device Specific Methods From: Srinivas Pandruvada To: Andy Shevchenko , Mario Limonciello Cc: Darren Hart , Alex Hung , Andy Shevchenko , Platform Driver , Linux Kernel Mailing List , "Rafael J. Wysocki" Date: Sat, 07 Jul 2018 16:37:52 -0700 In-Reply-To: References: <20180628181906.54910-1-srinivas.pandruvada@linux.intel.com> <74ac9bf130074e0a8f86a7904783d091@ausx13mpc120.AMER.DELL.COM> <95b3748fcb911c7305bd2bbcfd4e368f044f8b14.camel@linux.intel.com> <20180706235907.GE3041@fury> <1530935335264.5774@Dell.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.3 (3.28.3-1.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2018-07-07 at 19:24 +0300, Andy Shevchenko wrote: > On Sat, Jul 7, 2018 at 6:48 AM, wrote: > > > I strongly advocate for vendors to have more control over their > > > drivers, > > > but this scenario really frustrates me. I don't think I can > > > justify this > > > to Linus as a fix. But before we just say "no" (because hey, I > > > want > > > these fixes available as early as possible too), let's ask Rafael > > > if he > > > has an opinion or if there is precedent for this in his > > > experience with > > > ACPI drivers in general: > > > > Full disclosure - an updated FW has since been rolled out that > > reverted this > > behavior back to previous FW behavior due to lack of Linux support > > for the > > new _DSM. There is desire to use the new interface (as it did fix > > actual > > problems with the old one) so at some point it may return. When > > that happens > > it would be ideal that people who are (for example) running an LTS > > kernel > > or distro kernel that tracks stable can pick it up too. > > I am all for the better user experience and bugs especially in FW > should be fixed, but I think to support all kind of behaviour the new > FW release should always provide a knob by which we can check if some > feature is supported or not. > > Above sounds to me as mistake in design of the fix. The fix here takes care of all the combination. If the new _DSM is available, it checks what functionality the _DSM interface can provide (Fn 0). For those functionality it gets using _DSM matching new FW interface. If there is no _DSM or _DSM doesn't provide the functionality or _DSM provided method fails, it still revert to old FW interface style using standalone method. Eventually because of configurable 5-button array, all platforms will be using new FW interface with consideration of backward compatibility. Thanks, Srinivas