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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,WEIRD_QUOTING 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 CBED6C4360C for ; Thu, 10 Oct 2019 09:08:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1E872067B for ; Thu, 10 Oct 2019 09:08:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387498AbfJJJI0 (ORCPT ); Thu, 10 Oct 2019 05:08:26 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:39835 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733144AbfJJJI0 (ORCPT ); Thu, 10 Oct 2019 05:08:26 -0400 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 46plcR3d7hz1rQCD; Thu, 10 Oct 2019 11:08:23 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 46plcR0bYQz1qqkQ; Thu, 10 Oct 2019 11:08:23 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id GACLg3BAFslI; Thu, 10 Oct 2019 11:08:20 +0200 (CEST) X-Auth-Info: 3yv9RJi5v/uCUl5RBM3UxIXknte+Kate4wyyjunP9RI= Received: from localhost.localdomain (85-222-111-42.dynamic.chello.pl [85.222.111.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Thu, 10 Oct 2019 11:08:20 +0200 (CEST) From: Lukasz Majewski To: linux-kernel@vger.kernel.org, Shawn Guo Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Mark Rutland , Rob Herring , Stefan Agner , Pengutronix Kernel Team , Sascha Hauer , Lukasz Majewski , Robin Murphy Subject: [PATCH v2] dts: Disable DMA support on the BK4 vf610 device's fsl_lpuart driver Date: Thu, 10 Oct 2019 11:08:02 +0200 Message-Id: <20191010090802.16383-1-lukma@denx.de> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This change disables the DMA support (RX/TX) on the NXP's fsl_lpuart driver - the PIO mode is used instead. This change is necessary for better robustness of BK4's device use cases with many potentially interrupted short serial transfers. Without it the driver hangs when some distortion happens on UART lines. Signed-off-by: Lukasz Majewski Suggested-by: Robin Murphy --- Changes for v2: - Use /delete-property/dma-names; instead of dma-names = "",""; --- arch/arm/boot/dts/vf610-bk4.dts | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm/boot/dts/vf610-bk4.dts b/arch/arm/boot/dts/vf610-bk4.dts index 0f3870d3b099..830c85476b3d 100644 --- a/arch/arm/boot/dts/vf610-bk4.dts +++ b/arch/arm/boot/dts/vf610-bk4.dts @@ -259,24 +259,28 @@ &uart0 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart0>; + /delete-property/dma-names; status = "okay"; }; &uart1 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart1>; + /delete-property/dma-names; status = "okay"; }; &uart2 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart2>; + /delete-property/dma-names; status = "okay"; }; &uart3 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart3>; + /delete-property/dma-names; status = "okay"; }; -- 2.20.1