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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 B2A49C43331 for ; Thu, 2 Apr 2020 09:48:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85DB52074D for ; Thu, 2 Apr 2020 09:48:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585820897; bh=tQn980VNVD2NF8f3vV6R1mgERuk6VHI+6dEM25XXfqI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ylAccX2CyA/jgiOpnbEflyG0H2iQAUTeh130KLIycgXjFdx6HMLUr2YBTvNBLiVgI tCOr4leI25ZgQ4SJnMBGDcLMBMOcy8km7jkqmUnRZ9YS/vv4qPxVO26cMtFsls4oiN WujNyiPcPA91+SNiV+J/1f4Ae0Mn0ee7BmFek8vc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387911AbgDBJsO (ORCPT ); Thu, 2 Apr 2020 05:48:14 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:44705 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725965AbgDBJsO (ORCPT ); Thu, 2 Apr 2020 05:48:14 -0400 Received: by mail-ed1-f67.google.com with SMTP id i16so3301937edy.11; Thu, 02 Apr 2020 02:48:12 -0700 (PDT) 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:user-agent; bh=EebgA10aQonHAdiMTRoJOB7z11b/IU502qlsS+rdf6o=; b=HQjEdUKPZeSEOI8knQyUZQUexZP58MzcnenQuTu7L5Ea9Qsk5uPlEba7VWaq2ybhN+ oXm4P8J+OckTV691brK5BNdpwXDhBjCcr9i7RmifNbb3Y70TmZ7MTxopEguf88kyrrjR BxLG4/J6jIf60XJP6OGBPeld8RwLFbiEUZPDXtMlfRr/3nNmmu7QJjOAM/jU+MTgNK26 3qpCLx4jr0T0ABTIFAV1Bv0JkiXRC80Jyofzct2JuGUJOFBAzxxTJKah9S3xlXWE7IWT wJXiTaaBspvcYlBZl1cD9A/L5dSXtIGNz4hTNAb2QU6dnAt41c7mw82df82vQnMAf853 HOiQ== X-Gm-Message-State: AGi0PubhvGdIxpIvMKbWtpbWQE96Ceegv+wAIIhMnkzDnBxSua9nsUPP r//ieJ2+Y68aXLjL4Hro6O+7EGzi X-Google-Smtp-Source: APiQypIF74oGksjMDueJN1n5kxiy+DMCIipIZolflLnnlWIJFFfGO84ldJuhdl2ALOj87wiqKoQ0fQ== X-Received: by 2002:a17:906:9ca:: with SMTP id r10mr2262131eje.151.1585820891869; Thu, 02 Apr 2020 02:48:11 -0700 (PDT) Received: from kozik-lap ([194.230.155.125]) by smtp.googlemail.com with ESMTPSA id qk2sm1008399ejb.80.2020.04.02.02.48.10 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 02 Apr 2020 02:48:11 -0700 (PDT) Date: Thu, 2 Apr 2020 11:48:08 +0200 From: 'Krzysztof Kozlowski' To: Hyunki Koo Cc: 'Greg Kroah-Hartman' , hyunki00.koo@gmail.com, 'Kukjin Kim' , 'Jiri Slaby' , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] tty: samsung_tty: 32-bit access for TX/RX hold registers Message-ID: <20200402094808.GA21903@kozik-lap> References: <20200401082721.19431-1-hyunki00.koo@samsung.com> <20200401085548.GC2026666@kroah.com> <20200401091952.GA14425@kozik-lap> <000001d608d3$5faa8260$1eff8720$@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <000001d608d3$5faa8260$1eff8720$@samsung.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Thu, Apr 02, 2020 at 06:44:58PM +0900, Hyunki Koo wrote: > On Wed, Apr 01, 2020 at 6:20:20PM +0900, Krzysztof Kozlowski > wrote: > > On Wed, Apr 01, 2020 at 10:55:48AM +0200, Greg Kroah-Hartman > > wrote: > > > On Wed, Apr 01, 2020 at 05:27:20PM +0900, Hyunki Koo wrote: > > > > - if (np) > > > > + if (np) { > > > > of_property_read_u32(np, > > > > "samsung,uart-fifosize", &ourport->port.fifosize); > > > > > > > > + if (of_property_read_u32(np, "reg-io-width", &prop) == > > 0) { > > > > + switch (prop) { > > > > + case 1: > > > > + ourport->port.iotype = UPIO_MEM; > > > > + break; > > > > + case 4: > > > > + ourport->port.iotype = UPIO_MEM32; > > > > + break; > > > > + default: > > > > + dev_warn(&pdev->dev, "unsupported > > reg-io-width (%d)\n", > > > > + prop); > > > > + ret = -EINVAL; > > > > + break; > > > > + } > > > > + } > > > > + } > > > > + > > > > > > Does this mean that reg-io-width is now a required property for all > > > samsung uarts? Does this break older dts files? Or should you > > > fall-back to the previous operation if the attribute is not there? > > > > Yes, it looks like silently breaking all boards. Since > > of_property_read_u32() will return errno, the warning message won't be > > printed and all register reads will fail (return 0). > > > > This looks like not tested on real HW. > > > > Best regards, > > Krzysztof > > [Hyunki Koo] > reg-io-width =4 is required for Samsung uart > To do not break older dts files, I will set default value in else of of_property_read_u32 like below. > + if (of_property_read_u32(np, "reg-io-width", &prop) == 0) { > + ... > + } else { > + ourport->port.iotype = UPIO_MEM; > + } Thanks. Also, please test your patch on available Exynos boards, e.g. Odroid XU4 or HC1. Best regards, Krzysztof