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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 0F69BC46461 for ; Wed, 12 May 2021 18:19:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC770613C3 for ; Wed, 12 May 2021 18:19:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232344AbhELSTJ (ORCPT ); Wed, 12 May 2021 14:19:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:42392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236450AbhELQ3M (ORCPT ); Wed, 12 May 2021 12:29:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0C42361353; Wed, 12 May 2021 15:56:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620835005; bh=pUW+uy/EbG8u/g2VfSdmXn8uvH4oH94jims3k28uwVc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VAOOojWOBOudO9EE/iujyXgFTuKHf5lw1qj4nbDP1PajHJFhfrYBKIdxnHG+QSLdE I2jVMCqTOo7NZS8u+MeGODBcpz8aTFS1+znoz6TwDh+0pfLODFMYQV8m/UTQH9RLYe WjbBnLd2oN+UHlzVb5Nfv22IJMzW1m0o9qhpjCTY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Erwan Le Ray , Sasha Levin Subject: [PATCH 5.12 170/677] serial: stm32: add FIFO flush when port is closed Date: Wed, 12 May 2021 16:43:36 +0200 Message-Id: <20210512144842.887154298@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Erwan Le Ray [ Upstream commit 9f77d19207a0e8ba814c8ceb22e90ce7cb2aef64 ] Transmission complete error is sent when ISR_TC is not set. If port closure is requested despite data in TDR / TX FIFO has not been sent (because of flow control), ISR_TC is not set and error message is sent on port closure but also when a new port is opened. Flush the data when port is closed, so the error isn't printed twice upon next port opening. Fixes: 64c32eab6603 ("serial: stm32: Add support of TC bit status check") Signed-off-by: Erwan Le Ray Link: https://lore.kernel.org/r/20210304162308.8984-12-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/stm32-usart.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 183c76ddb165..d205fce1950a 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -691,6 +691,11 @@ static void stm32_usart_shutdown(struct uart_port *port) if (ret) dev_err(port->dev, "Transmission is not complete\n"); + /* flush RX & TX FIFO */ + if (ofs->rqr != UNDEF_REG) + writel_relaxed(USART_RQR_TXFRQ | USART_RQR_RXFRQ, + port->membase + ofs->rqr); + stm32_usart_clr_bits(port, ofs->cr1, val); free_irq(port->irq, port); -- 2.30.2