From patchwork Tue Aug 8 16:19:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Caron X-Patchwork-Id: 712562 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A93F5C001B0 for ; Tue, 8 Aug 2023 18:49:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232905AbjHHSti (ORCPT ); Tue, 8 Aug 2023 14:49:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232865AbjHHStV (ORCPT ); Tue, 8 Aug 2023 14:49:21 -0400 Received: from mx07-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B95E26E9E; Tue, 8 Aug 2023 10:01:19 -0700 (PDT) Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.22/8.17.1.22) with ESMTP id 378Co9RM027282; Tue, 8 Aug 2023 18:20:43 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= selector1; bh=qK+bLNEf/yd307CslLlG3mAR8/FcQJFZFqOUnUtJAh8=; b=L4 8PETXXDAlTQ+H366hlsEfdOGvtNU+zzJ6h55/fP9lJKsbGfZIJYcRMQW7hKX6iJR CCU0MSVXQs1yVZAqh9QbeRADS6jcybVcUl4pnaGsMbcFFZ/NOZnuWGWVizSL9zNi l+giYVqIUQNbKk0elPGuqSLL3UPfm8hfhOl/ZOfe10rZdk8kHzHkv6ure/d9ujgh lkATtkmE6s8rXip/W4l0PWogfDff4ju31yptYqsTHsmEI9Ph7XLdO+j9PSc+8/Yc 8QZ5ig9LmEbrLS8aMYhgw4PfBhH5U0fEAMs0cQEmv3yuitI6QZDrDGUWfSNj7Eh7 SNveOMC4Mf4GMkTPZ97A== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3sbp2d95fu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 08 Aug 2023 18:20:43 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 85C10100062; Tue, 8 Aug 2023 18:20:42 +0200 (CEST) Received: from Webmail-eu.st.com (eqndag1node4.st.com [10.75.129.133]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 7DDBC236928; Tue, 8 Aug 2023 18:20:42 +0200 (CEST) Received: from localhost (10.201.20.168) by EQNDAG1NODE4.st.com (10.75.129.133) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 8 Aug 2023 18:20:42 +0200 From: Valentin Caron To: Greg Kroah-Hartman CC: Jiri Slaby , Alexandre Torgue , Amelie Delaunay , , , , , Valentin Caron Subject: [PATCH v2 6/6] serial: stm32: synchronize RX DMA channel in shutdown Date: Tue, 8 Aug 2023 18:19:06 +0200 Message-ID: <20230808161906.178996-7-valentin.caron@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230808161906.178996-1-valentin.caron@foss.st.com> References: <20230808161906.178996-1-valentin.caron@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.201.20.168] X-ClientProxiedBy: EQNCAS1NODE3.st.com (10.75.129.80) To EQNDAG1NODE4.st.com (10.75.129.133) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.957,Hydra:6.0.591,FMLib:17.11.176.26 definitions=2023-08-08_15,2023-08-08_01,2023-05-22_02 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Amelie Delaunay In shutdown, RX DMA channel is terminated. If the DMA RX callback is scheduled but not yet executed, while a new RX DMA transfer is started, the callback can be executed, and then disturb the ongoing RX DMA transfer. To avoid such a case, call dmaengine_synchronize in shutdown, after the DMA RX channel is terminated. Signed-off-by: Amelie Delaunay Signed-off-by: Valentin Caron --- drivers/tty/serial/stm32-usart.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 8fc0526be898..5e9cf0c48813 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -1123,8 +1123,10 @@ static void stm32_usart_shutdown(struct uart_port *port) dev_err(port->dev, "Transmission is not complete\n"); /* Disable RX DMA. */ - if (stm32_port->rx_ch) + if (stm32_port->rx_ch) { stm32_usart_rx_dma_terminate(stm32_port); + dmaengine_synchronize(stm32_port->rx_ch); + } /* flush RX & TX FIFO */ if (ofs->rqr != UNDEF_REG)