From patchwork Tue Jan 4 18:24:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Caron X-Patchwork-Id: 12703776 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 18962C433F5 for ; Tue, 4 Jan 2022 18:27:46 +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=Mj//uSxw6gkumgUYAaULSsBJ4ZNfZuKVhu0cKlHCpuY=; b=xib1YLRwvM2wp3 qgpUv33sDzTrWtKNgQGPeeYVpAs4Dlfz5Oxuo5IlEJkxn2pLJKmnLpPGNAH6EJB9zZclxEUYLmQJg OFK1oC+ySFDixznZLZMM8Q6Opay9ntzrC4N2w4Vr9UbATcS5sdmVoAazsWhVh6Ka33aJ2yR/Wvfxp c752KsX/to3gq6zAl8Ocw2ozGCXUbOQ3Rhf2LofQW+xdbo+8lT9FBPU8Ke2vBQOva3HT7dWWzoq05 9x85MVO4n4FydUTzn/l1o+77krCtLhMz4DzzCB1f7IHanXFF69my8n0dfrdIBuLmWftI0Nc248u/T DFx8KlVaUM3wPorzneRg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n4oVv-00CU2J-DW; Tue, 04 Jan 2022 18:26:27 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n4oVV-00CTuk-9k for linux-arm-kernel@lists.infradead.org; Tue, 04 Jan 2022 18:26:03 +0000 Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 204FQG3K032620; Tue, 4 Jan 2022 19:25:52 +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=5bcwS38T/HZMOjrZpC28q7ZFA6+/QWchHVmneYfJfeE=; b=FBoxAasqPWRIkJDBDUIsINVqVUj+cTanpvDBg8RjJyV39wzE22vpR7y9anOyjmJJyKlj tjUy4nSfoi9RMcQcKg2FHBB+ecrV74FKyM1gIINos4a/F/57T0zl46eqA2jrBeU+anN+ EssXoPmKRvJSIOHGui2Yv6L7DTJVqLUk5tKOj1cypF1fsbLkPz5CCA8YPnnWZwKe3btp 8kfyu0BPTUWhBvKVFYAFNIEaznm3u87eWi6nwJN9j074UU8ubt9zu/qgXLA8xO8sMzs1 j2z29MQxqFQNRr2wlSZ6chWPdgL0wmjvdSZ7ranfgz2a0EiegJsuk7oYrMtj5/Y+JL5P mA== 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 3dcagrc7wj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 04 Jan 2022 19:25:52 +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 ABC8F10002A; Tue, 4 Jan 2022 19:25:51 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag2node2.st.com [10.75.127.5]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id A5D9E24D5E6; Tue, 4 Jan 2022 19:25:51 +0100 (CET) Received: from localhost (10.75.127.44) by SFHDAG2NODE2.st.com (10.75.127.5) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Tue, 4 Jan 2022 19:25:50 +0100 From: Valentin Caron To: Greg Kroah-Hartman CC: Jiri Slaby , Maxime Coquelin , Alexandre Torgue , Gerald Baeza , Erwan Le Ray , Valentin Caron , , , , Subject: [PATCH 4/4] serial: stm32: correct loop for dma error handling Date: Tue, 4 Jan 2022 19:24:45 +0100 Message-ID: <20220104182445.4195-5-valentin.caron@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220104182445.4195-1-valentin.caron@foss.st.com> References: <20220104182445.4195-1-valentin.caron@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] 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=2022-01-04_09,2022-01-04_01,2021-12-02_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220104_102601_668225_FBF6347E X-CRM114-Status: GOOD ( 17.41 ) 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 In this error handling, "transmit_chars_dma" function will call "transmit_chars_pio" once per characters. But "transmit_chars_pio" will continue to send characters while xmit buffer is not empty. Remove this useless loop, one call is sufficient. Signed-off-by: Valentin Caron --- drivers/tty/serial/stm32-usart.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 788e002688f2..1f89ab0e49ac 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -477,7 +477,7 @@ static void stm32_usart_transmit_chars_dma(struct uart_port *port) const struct stm32_usart_offsets *ofs = &stm32port->info->ofs; struct circ_buf *xmit = &port->state->xmit; struct dma_async_tx_descriptor *desc = NULL; - unsigned int count, i; + unsigned int count; if (stm32_usart_tx_dma_started(stm32port)) { if (!stm32_usart_tx_dma_enabled(stm32port)) @@ -542,8 +542,7 @@ static void stm32_usart_transmit_chars_dma(struct uart_port *port) return; fallback_err: - for (i = count; i > 0; i--) - stm32_usart_transmit_chars_pio(port); + stm32_usart_transmit_chars_pio(port); } static void stm32_usart_transmit_chars(struct uart_port *port)