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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 833E8C10F13 for ; Mon, 8 Apr 2019 10:09:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 536A120883 for ; Mon, 8 Apr 2019 10:09:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726373AbfDHKJv (ORCPT ); Mon, 8 Apr 2019 06:09:51 -0400 Received: from mga14.intel.com ([192.55.52.115]:16373 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725881AbfDHKJu (ORCPT ); Mon, 8 Apr 2019 06:09:50 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Apr 2019 03:09:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,324,1549958400"; d="scan'208";a="138453667" Received: from smile.fi.intel.com (HELO smile) ([10.237.72.86]) by fmsmga008.fm.intel.com with ESMTP; 08 Apr 2019 03:09:48 -0700 Received: from andy by smile with local (Exim 4.92) (envelope-from ) id 1hDRDn-0006e0-HG; Mon, 08 Apr 2019 13:09:47 +0300 Date: Mon, 8 Apr 2019 13:09:47 +0300 From: Andy Shevchenko To: Mika Westerberg Cc: Chris Chiu , heikki.krogerus@linux.intel.com, drake@endlessm.com, linus.walleij@linaro.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, linux@endlessm.com Subject: Re: [PATCH] pinctrl:intel: Retain HOSTSW_OWN for requested gpio pin Message-ID: <20190408100947.GI9224@smile.fi.intel.com> References: <20190408042103.3804-1-chiu@endlessm.com> <20190408074106.GC3622@lahna.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190408074106.GC3622@lahna.fi.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 08, 2019 at 10:41:06AM +0300, Mika Westerberg wrote: > On Mon, Apr 08, 2019 at 12:21:03PM +0800, Chris Chiu wrote: > > +static void static u32 (see below why) > > +intel_gpio_update_pad_mode(void __iomem *hostown, u32 mask, u32 value) > > +{ > > + u32 curr = readl(hostown); > > + u32 updated = (curr & ~mask) | (value & mask); > > I think here we should first complain if the expected ownership is not > correct. Warning or info level probably enough. It is easy to achieve, something like if ((value ^ saved) & requeted) dev_warn(...); See also below. (I had mentioned this earlier) > > + return writel(updated, hostown); writel() is a void function, this is wrong. We need to return curr instead to make above working to issue a warning message. > Also if the pin is not requested and not changed we should not touch the > register. I don't think it brings any value here, if mask is 0 we will write back the same value we read. > Otherwise this looks good to me. -- With Best Regards, Andy Shevchenko