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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 A27D0C33CAF for ; Thu, 16 Jan 2020 17:15:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7598E246A0 for ; Thu, 16 Jan 2020 17:15:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194913; bh=rrhEdS2kNqQJmlV3Thq14xN8wxbM2iGtBl9NJUCf7u4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iklNYWtkBFGrz0PPEoxV/BBhRe70m6j3Srx1f4fo3vuN744zJjCaXsMPM3q2SCEzY CCVA0dh81Lod4eXzdNiklx7D5YzM9HcCtPCERvOFpvb21vbBb2RiMKBW7wKMYCEs1J USRWPjx9aWGWby6lQni3QDM69e+2PHzVt6tgX9Bk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391124AbgAPRPF (ORCPT ); Thu, 16 Jan 2020 12:15:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:34382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391067AbgAPROm (ORCPT ); Thu, 16 Jan 2020 12:14:42 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E58BA24690; Thu, 16 Jan 2020 17:14:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194881; bh=rrhEdS2kNqQJmlV3Thq14xN8wxbM2iGtBl9NJUCf7u4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h0zos+81pQSw5ZbCtZwpHeusU6qIwyRJLsNImJLc70bLNQoZV209RcQHhpOMU5PXi paeIGCYrgbsfAaZU0tHjoATPFmcsZ9cxno08b25PeuieE6DHxDUay1WnZvlqz2Dugs /VGSlzQg7qb7yMvRXVtg53UHlZBHN93Op2k/CEDg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Fabrice Gasnier , Greg Kroah-Hartman , Sasha Levin , linux-serial@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 4.19 670/671] serial: stm32: fix clearing interrupt error flags Date: Thu, 16 Jan 2020 12:05:08 -0500 Message-Id: <20200116170509.12787-407-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Fabrice Gasnier [ Upstream commit 1250ed7114a977cdc2a67a0c09d6cdda63970eb9 ] The interrupt clear flag register is a "write 1 to clear" register. So, only writing ones allows to clear flags: - Replace buggy stm32_clr_bits() by a simple write to clear error flags - Replace useless read/modify/write stm32_set_bits() routine by a simple write to clear TC (transfer complete) flag. Fixes: 4f01d833fdcd ("serial: stm32: fix rx error handling") Signed-off-by: Fabrice Gasnier Cc: stable Link: https://lore.kernel.org/r/1574323849-1909-1-git-send-email-fabrice.gasnier@st.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/stm32-usart.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index d096e552176c..bce4ac1787ad 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -239,8 +239,8 @@ static void stm32_receive_chars(struct uart_port *port, bool threaded) * cleared by the sequence [read SR - read DR]. */ if ((sr & USART_SR_ERR_MASK) && ofs->icr != UNDEF_REG) - stm32_clr_bits(port, ofs->icr, USART_ICR_ORECF | - USART_ICR_PECF | USART_ICR_FECF); + writel_relaxed(sr & USART_SR_ERR_MASK, + port->membase + ofs->icr); c = stm32_get_char(port, &sr, &stm32_port->last_res); port->icount.rx++; @@ -409,7 +409,7 @@ static void stm32_transmit_chars(struct uart_port *port) if (ofs->icr == UNDEF_REG) stm32_clr_bits(port, ofs->isr, USART_SR_TC); else - stm32_set_bits(port, ofs->icr, USART_ICR_TCCF); + writel_relaxed(USART_ICR_TCCF, port->membase + ofs->icr); if (stm32_port->tx_ch) stm32_transmit_chars_dma(port); -- 2.20.1