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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 4A4F0C2BA83 for ; Thu, 13 Feb 2020 09:51:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2622820848 for ; Thu, 13 Feb 2020 09:51:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729754AbgBMJvV (ORCPT ); Thu, 13 Feb 2020 04:51:21 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:40735 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729440AbgBMJvV (ORCPT ); Thu, 13 Feb 2020 04:51:21 -0500 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j2B9U-0004Bt-BY; Thu, 13 Feb 2020 10:51:20 +0100 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.89) (envelope-from ) id 1j2B9T-0002gj-H2; Thu, 13 Feb 2020 10:51:19 +0100 Date: Thu, 13 Feb 2020 10:51:19 +0100 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Anson Huang Cc: "mark.rutland@arm.com" , "devicetree@vger.kernel.org" , "shawnguo@kernel.org" , "s.hauer@pengutronix.de" , "linux-kernel@vger.kernel.org" , "robh+dt@kernel.org" , dl-linux-imx , "kernel@pengutronix.de" , "festevam@gmail.com" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] ARM: dts: imx6sx: Add missing uart mux function Message-ID: <20200213095119.f6obrdqb6ql76qqy@pengutronix.de> References: <1581576189-20490-1-git-send-email-Anson.Huang@nxp.com> <20200213072710.4snwbo3i7vfbroqy@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hello Anson, On Thu, Feb 13, 2020 at 09:18:10AM +0000, Anson Huang wrote: > > On Thu, Feb 13, 2020 at 02:43:09PM +0800, Anson Huang wrote: > > > From: Anson Huang > > > > > > Update i.MX6SX pinfunc header to add uart mux function. > > > > I'm aware you add the macros in a consistent way to the already existing > > stuff. Still I think there is something to improve here. We now have > > definitions like: > > > > MX6SX_PAD_GPIO1_IO06__UART1_RTS_B > > MX6SX_PAD_GPIO1_IO06__UART1_CTS_B > > > > MX6SX_PAD_GPIO1_IO07__UART1_CTS_B > > MX6SX_PAD_GPIO1_IO07__UART1_RTS_B > > > > where (ignoring other pins that could be used) only the following > > combinations are valid: > > > > MX6SX_PAD_GPIO1_IO04__UART1_TX > > MX6SX_PAD_GPIO1_IO05__UART1_RX > > MX6SX_PAD_GPIO1_IO06__UART1_RTS_B > > MX6SX_PAD_GPIO1_IO07__UART1_CTS_B > > > > (in DCE mode) and > > > > MX6SX_PAD_GPIO1_IO04__UART1_RX > > MX6SX_PAD_GPIO1_IO05__UART1_TX > > MX6SX_PAD_GPIO1_IO06__UART1_CTS_B > > MX6SX_PAD_GPIO1_IO07__UART1_RTS_B > > > > (in DTE mode). > > Is it possible the using below combination, if possible, then I think the prefix "DTE/DCE" are > NOT impacting real functions, they are just different names for better identification: > > MX6SX_PAD_GPIO1_IO04__UART1_TX > MX6SX_PAD_GPIO1_IO05__UART1_RX > MX6SX_PAD_GPIO1_IO06__UART1_CTS_B > MX6SX_PAD_GPIO1_IO07__UART1_RTS_B This is wrong according to my experience. If you look at the diagram in the i.MX6SX RM in the External Signals chapter (page 4111 in the IMX6SXRM Rev. 2, 9/2017) you can only either use RX/TX and RTS/CTS for their original purpose, or swap both pairs together. > > For i.MX6SLL, i.MX6UL, imx6ULL and i.MX7 the naming convention is saner, a > > typical definition there is: > > > > MX7D_PAD_LPSR_GPIO1_IO04__UART5_DTE_RTS > > > > where the name includes DTE and where is it (more) obvious that this cannot > > be combined with > > > > MX7D_PAD_LPSR_GPIO1_IO07__UART5_DCE_TX > > > > . > > > > I suggest to adapt the latter naming convention also for the other i.MX > > pinfunc headers, probably with introducing defines for not breaking existing > > dts files. > > If to improve the name, just change the existing dts files which use them should be OK, > as this header file ONLY used by DT and should be no compatible issues. So should I > change the dts files together? My approach would be one patch for each of: - rename existing imx6sx symbols to contain DTE or DCE (introducing defines that map the old name to the new) - introduce the new defines you added in your patch under discussion here (with the new naming scheme obviously) - switch all in-tree consumers to the new names (maybe offering to split per machine) I would also drop the _B suffix in the first patch which serves no useful purpose. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |