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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 D6ACAC43461 for ; Fri, 21 May 2021 06:44:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B26A1611AD for ; Fri, 21 May 2021 06:44:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234158AbhEUGpo (ORCPT ); Fri, 21 May 2021 02:45:44 -0400 Received: from mleia.com ([178.79.152.223]:54480 "EHLO mail.mleia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233652AbhEUGpd (ORCPT ); Fri, 21 May 2021 02:45:33 -0400 Received: from mail.mleia.com (localhost [127.0.0.1]) by mail.mleia.com (Postfix) with ESMTP id 5050F39A5; Fri, 21 May 2021 06:44:10 +0000 (UTC) Subject: Re: [PATCH v3 3/3] pinctrl: single: set pinmux from pins debug file To: Dario Binacchi , linux-kernel@vger.kernel.org Cc: Tony Lindgren , Drew Fustini , Linus Walleij , Andy Shevchenko , Haojian Zhuang , linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, linux-omap@vger.kernel.org References: <20210520202730.4444-1-dariobin@libero.it> <20210520202730.4444-4-dariobin@libero.it> From: Vladimir Zapolskiy Message-ID: <2ef7f7f9-b147-8292-85fb-bcf58a2b6428@mleia.com> Date: Fri, 21 May 2021 09:44:09 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210520202730.4444-4-dariobin@libero.it> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-49551924 X-CRM114-CacheID: sfid-20210521_064410_352838_FA42BC3B X-CRM114-Status: UNSURE ( 9.37 ) X-CRM114-Notice: Please train this message. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Dario, On 5/20/21 11:27 PM, Dario Binacchi wrote: > As described in section 9.1 of the TI reference manual for AM335x [1], > "For writing to the control module registers, the MPU will need to be in > privileged mode of operation and writes will not work from user mode". > By adding the pin_dbg_set helper to pcs_pinctrl_ops it will be possible > to write these registers from the pins debug: this makes little sense, because it should be possible to write to the registers without introduction of this interface, pin group/function is the right level of abstraction for your particular task. > cd /sys/kernel/debug/pinctrl/44e10800.pinmux-pinctrl-single/ > echo >pins > > [1] https://www.ti.com/lit/ug/spruh73q/spruh73q.pdf > > Signed-off-by: Dario Binacchi I strongly object against this new interface to be added. -- Best wishes, Vladimir