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: 13346326 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5C48EC04FDF for ; Tue, 8 Aug 2023 16:21:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ce/cdJVN2XBxAk9sQEeZdn2BPBgALoiL3eTtK9xyxj0=; b=e4lGr6sIj2g6bt AEvZihI7nk8wxVP9KzJP5zRlOUYo1HT80ig3Faqm8j45fwCP51udwc0aVEBDIZZk6eISZjDyYcjLK 1dcgLgT8QUdtvZXJAGsgEdg9Gs77Plg2BrRQqNgiXi3DKQNWQbFaAvkbei4pc43wZiPlqFaOZYvLp r3pKF5KK+osiRnRzbwbhXX/YGQYa5zBKArn6VoFvOdAFUogYBR7L7xNziBrm3crl9n0sifsFQwMbg cuDclbGcaMNbUZ4X4djhuhbubuM7NJfDpDOVSCxhnWnFVQFWQhj/sHyLGFeofpC0VFm4LEXJWozPK 7C69wHQA8mD8zlSd/HRQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qTPS5-002xOi-0F; Tue, 08 Aug 2023 16:20:57 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qTPS2-002xKb-0w for linux-arm-kernel@lists.infradead.org; Tue, 08 Aug 2023 16:20:55 +0000 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230808_092054_619928_D517B7CB X-CRM114-Status: GOOD ( 13.01 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.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)