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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 97D4DC43461 for ; Sun, 13 Sep 2020 19:42:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DC332076C for ; Sun, 13 Sep 2020 19:42:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=beagleboard-org.20150623.gappssmtp.com header.i=@beagleboard-org.20150623.gappssmtp.com header.b="WWoza80l" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725968AbgIMTmn (ORCPT ); Sun, 13 Sep 2020 15:42:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34186 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725938AbgIMTmj (ORCPT ); Sun, 13 Sep 2020 15:42:39 -0400 Received: from mail-ed1-x543.google.com (mail-ed1-x543.google.com [IPv6:2a00:1450:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D638DC06174A for ; Sun, 13 Sep 2020 12:42:37 -0700 (PDT) Received: by mail-ed1-x543.google.com with SMTP id t16so15550634edw.7 for ; Sun, 13 Sep 2020 12:42:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=beagleboard-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=k2cvB0HQArtJknBkltHAoCpwXnIH5D4KwvQqQMifHm4=; b=WWoza80lwFN2cSIWNPpF9RO03s6vxAsB42qYdTC+2typ17TgiQsuQj2R+PaBHA24Mc X0NsWurndtM13ubMmMe7uzPhq1Opu5a170YrnmE2bVIwNwwaVBw83JkdWh7bQPu8fZ2H cqWL+xe6KzHNVp66cZeZTtUrk46ajDsyf3bfaiUDApWx9r90psJVxlx9rPM4vYP5413U cdL5I8USziB8vGrhrakS2Xj1zIJCfCVHB+ScOFXRKYfXvhpePasFd6ficE58V5tXEWFZ oydEoP3ObwzEN7oxrp5I6V0/czFh2JACXJJMwIyObuR1D8K99HglGuojcpq5UnVU4wXN +ccw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=k2cvB0HQArtJknBkltHAoCpwXnIH5D4KwvQqQMifHm4=; b=tg1mSvIEI7AIvtIf6pMJHn1EVquXp2LNvpKz+zRdXHrwfETiWtumtwfIpZwhcRmGVn og2XrjA2ZMmjRgSL3wYjh81kv7TjIfWY/nsTfa8IBqZlCU9HB1Hps3jI/L6VNqy9Ld3h jQcvhPE/SGHqQc7Pq8/Xe79srA59LVD5WP1q7wADTlnV4OmItbD4mxeEDu3Xa5WXLqpu qveBS3weZWjTH+Uis7CPapPQqvcrYUXXs5NSE4PJm+AYXjlntcsqSJJGgjO7K46Tp+19 4SPVsWF+gOpH8tAWTTcN2nvbjuz5E+TJWeyD1HLCHm6iecmem6m+aW0lQW3+Q+81C7lB ZoZw== X-Gm-Message-State: AOAM532bQ9QHPKz9tAbPvxxrta32hI5p47qlTSO7ozV6ZHhVBBCVYL6c WPbNvmLisn18/PX/7+NihCKCdg== X-Google-Smtp-Source: ABdhPJz7OvHoMkyN0c1qJ1xvIg2tXwvkdR2sb0uzsGhQB0HjoTTy1q871OAMdzLfTfJEW5qDmRtJCQ== X-Received: by 2002:a05:6402:326:: with SMTP id q6mr14107023edw.216.1600026156541; Sun, 13 Sep 2020 12:42:36 -0700 (PDT) Received: from x1 ([2001:16b8:5cf8:e601:5f2:8f03:4748:2bc6]) by smtp.gmail.com with ESMTPSA id bf25sm7685811edb.95.2020.09.13.12.42.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 13 Sep 2020 12:42:35 -0700 (PDT) Date: Sun, 13 Sep 2020 21:42:33 +0200 From: Drew Fustini To: Trent Piepho Cc: linux-arm-kernel@lists.infradead.org, Tony Lindgren , Rob Herring , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, Linus Walleij , Haojian Zhuang , devicetree@vger.kernel.org, bcousson@baylibre.com, Jason Kridner , Robert Nelson Subject: Re: [PATCH v4 1/2] pinctrl: single: parse #pinctrl-cells = 2 Message-ID: <20200913194233.GA1955808@x1> References: <20200701013320.130441-1-drew@beagleboard.org> <20200701013320.130441-2-drew@beagleboard.org> <3139716.CMS8C0sQ7x@zen.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3139716.CMS8C0sQ7x@zen.local> Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Tue, Sep 08, 2020 at 04:52:58PM -0700, Trent Piepho wrote: > On Tuesday, June 30, 2020 6:33:19 PM PDT Drew Fustini wrote: > > If "pinctrl-single,pins" has 3 arguments (offset, conf, mux), then > > pcs_parse_one_pinctrl_entry() does an OR operation on conf and mux to > > get the value to store in the register. > > > > - vals[found].val = pinctrl_spec.args[1]; > > + > > + switch (pinctrl_spec.args_count) { > > + case 2: > > + vals[found].val = pinctrl_spec.args[1]; > > + break; > > + case 3: > > + vals[found].val = (pinctrl_spec.args[1] | > pinctrl_spec.args[2]); > > + break; > > + } > > > > dev_dbg(pcs->dev, "%pOFn index: 0x%x value: 0x%x\n", > > pinctrl_spec.np, offset, > pinctrl_spec.args[1]); > > If #pinctrl-cells value is greater than 2, nothing will set vals[found].val to > anything other than zero (from when it's calloc'ed) and the pinctrl will > silently be programmed to zero. If #pinctrl-cells is 3, then it will be: vals[found].val = (pinctrl_spec.args[1] | pinctrl_spec.args[2]); Do you mean if #pinctrl-cells is great than 3 then it will just have a default value of zero? That does appear to be the case and is probably not the behavior we want. Thank you for pointing this out. Earlier, there is a check to make sure there are at least 2 arguments: if (pinctrl_spec.args_count < 2) { dev_err(pcs->dev, "invalid args_count for spec: %i\n", pinctrl_spec.args_count); break; } I'll submit a patch where the upper bound is also checked: if (pinctrl_spec.args_count < 2 || pinctrl_spec.args_count > 3) { dev_err(pcs->dev, "invalid args_count for spec: %i\n", pinctrl_spec.args_count); break; } > The debug printout was not change to print vals[found].val, so it will > continue to print the value of the 2nd cell. Thank you for pointing this out. Yes, this is an oversight and I will submit a patch. > The result is that a #pinctrl-cells of 3 will produce no warning or error, > program the pinctrl to zero, whilst at the same time emit debug log messages > that it is programming the expected values. > > The device tree documentation still states that #pinctrl-cells must be 1 when > using pinctrl-single,pins. This new special case of ORing two values is not > documented. This is a good point, too. I will make a patch to update the documentation. -Drew