From patchwork Tue Jan 11 16:44:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Caron X-Patchwork-Id: 531409 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 80EB7C433F5 for ; Tue, 11 Jan 2022 16:45:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343834AbiAKQpr (ORCPT ); Tue, 11 Jan 2022 11:45:47 -0500 Received: from mx07-00178001.pphosted.com ([185.132.182.106]:53632 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244179AbiAKQpp (ORCPT ); Tue, 11 Jan 2022 11:45:45 -0500 Received: from pps.filterd (m0241204.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 20BBoEdc023994; Tue, 11 Jan 2022 17:45:27 +0100 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-type; s=selector1; bh=HadlWm8vPa6gLGI+Lp8NuxhfCBgbLjPprgpIUAa/Nhs=; b=5D3HQTTKTA+NA0N4Kr33bvBZnp8rDT3ckfd7OqdskD1Qn79//ciQiEh6dpWgWCYzFmjb dKBNwWNI3XcSoYBr2+3DA4ENzVecprnEAxsuzOsY0/sHkNNEIbpuEELuBF2QLdiu/N7R iXQPfEEqO+3ZYK/kRg0Lz5NwsyLA/cIYgDAHBn/B+LmFof+Myf2Qy4A0EtSw+K/yo53f cyN0PRiBhYMX1qeJhRY2hqIlg30GJeolRX0cmOYk3PEoY72+ubBjbaq49JVT3Bo+awKg dZodkOS/T6mxs2l2CErR6I8tUBqWEY8zJ4B+sLTd8b9+WLmaQ39pG3JDYa7XU8eiMrj6 jQ== 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 3dh9cb9c6a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 11 Jan 2022 17:45:27 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id E2A4710002A; Tue, 11 Jan 2022 17:45:26 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag2node2.st.com [10.75.127.5]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id DB358245FC8; Tue, 11 Jan 2022 17:45:26 +0100 (CET) Received: from localhost (10.75.127.45) by SFHDAG2NODE2.st.com (10.75.127.5) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Tue, 11 Jan 2022 17:45:26 +0100 From: Valentin Caron To: Greg Kroah-Hartman CC: Jiri Slaby , Maxime Coquelin , Alexandre Torgue , Erwan Le Ray , Valentin Caron , , , , Subject: [PATCH 2/2] serial: stm32: fix software flow control transfer Date: Tue, 11 Jan 2022 17:44:41 +0100 Message-ID: <20220111164441.6178-3-valentin.caron@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220111164441.6178-1-valentin.caron@foss.st.com> References: <20220111164441.6178-1-valentin.caron@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.45] X-ClientProxiedBy: SFHDAG2NODE2.st.com (10.75.127.5) To SFHDAG2NODE2.st.com (10.75.127.5) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-01-11_04,2022-01-11_01,2021-12-02_01 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org x_char is ignored by stm32_usart_start_tx() when xmit buffer is empty. Fix start_tx condition to allow x_char to be sent. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Signed-off-by: Erwan Le Ray Signed-off-by: Valentin Caron --- drivers/tty/serial/stm32-usart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index c1b8828451c8..9570002d07e7 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -742,7 +742,7 @@ static void stm32_usart_start_tx(struct uart_port *port) struct serial_rs485 *rs485conf = &port->rs485; struct circ_buf *xmit = &port->state->xmit; - if (uart_circ_empty(xmit)) + if (uart_circ_empty(xmit) && !port->x_char) return; if (rs485conf->flags & SER_RS485_ENABLED) {