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=-8.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 48E1EC433FE for ; Mon, 7 Dec 2020 18:18:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1583D23888 for ; Mon, 7 Dec 2020 18:18:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726076AbgLGSSq (ORCPT ); Mon, 7 Dec 2020 13:18:46 -0500 Received: from mga04.intel.com ([192.55.52.120]:54445 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725823AbgLGSSq (ORCPT ); Mon, 7 Dec 2020 13:18:46 -0500 IronPort-SDR: gNWvaWZiL0Cl/3cWx9/joGU1iBpunwL03/vrNO15VEqfFaOeqjpknG6RA+aPPouy3BaM/cjbVA UwHSd4PsxCNQ== X-IronPort-AV: E=McAfee;i="6000,8403,9828"; a="171175516" X-IronPort-AV: E=Sophos;i="5.78,400,1599548400"; d="scan'208";a="171175516" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2020 10:17:01 -0800 IronPort-SDR: N5mDmen/M3aDzhOt6xnrZT4rS1oMtn0OsSfSC6OqWexJe2yMevtGX6dsziw3qYqG8UB3+yjpBo ryUo1IzI/2/A== X-IronPort-AV: E=Sophos;i="5.78,400,1599548400"; d="scan'208";a="363251574" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.163]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2020 10:16:58 -0800 Received: by lahna (sSMTP sendmail emulation); Mon, 07 Dec 2020 20:16:56 +0200 Date: Mon, 7 Dec 2020 20:16:56 +0200 From: Mika Westerberg To: Andy Shevchenko Cc: linux-gpio@vger.kernel.org, Linus Walleij , Pierre-Louis Bossart Subject: Re: [PATCH v1] pinctrl: intel: Actually disable Tx and Rx buffers on GPIO request Message-ID: <20201207181656.GZ5246@lahna.fi.intel.com> References: <20201207175940.10631-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201207175940.10631-1-andriy.shevchenko@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Mon, Dec 07, 2020 at 07:59:40PM +0200, Andy Shevchenko wrote: > Mistakenly the buffers (input and output) become together enabled for a little > period of time during GPIO request. This is problematic, because instead of > initial motive to disable them in the commit af7e3eeb84e2 > ("pinctrl: intel: Disable input and output buffer when switching to GPIO"), > the driven value on the pin, which might be used as an IRQ line, brings > firmware of some touch pads in an awkward state that needs a full power off > to recover. Fix this by, as stated in a culprit commit, disabling the buffers. > > Fixes: af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer when switching to GPIO") > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=210497 > Reported-by: Pierre-Louis Bossart > Signed-off-by: Andy Shevchenko Acked-by: Mika Westerberg