From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Smirnov Subject: [PATCH] tty: serial: fsl_lpuart: Fix lpuart_flush_buffer() Date: Fri, 4 Oct 2019 14:55:37 -0700 Message-ID: <20191004215537.5308-1-andrew.smirnov@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Greg Kroah-Hartman Cc: Andrey Smirnov , Stefan Agner , Andrew Lunn , Vivien Didelot , Chris Healy , Cory Tusar , Lucas Stach , Jiri Slaby , linux-imx@nxp.com, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-serial@vger.kernel.org Fix incorrect read-modify-write sequence in lpuart_flush_buffer() that was reading from UARTPFIFO and writing to UARTCFIFO instead of operating solely on the latter. Fixes: 9bc19af9dacb ("tty: serial: fsl_lpuart: Flush HW FIFOs in .flush_buffer") Signed-off-by: Andrey Smirnov Cc: Stefan Agner Cc: Andrew Lunn Cc: Vivien Didelot Cc: Chris Healy Cc: Cory Tusar Cc: Lucas Stach Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-imx@nxp.com Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- Greg: This bug causes occasional boot hang on 5.4-rc1 on Vybrid, so it might be good to push that for 5.4-rc2. Thanks, Andrey Sirnov drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3e17bb8a0b16..537896c4d887 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -548,7 +548,7 @@ static void lpuart_flush_buffer(struct uart_port *port) val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH; lpuart32_write(&sport->port, val, UARTFIFO); } else { - val = readb(sport->port.membase + UARTPFIFO); + val = readb(sport->port.membase + UARTCFIFO); val |= UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH; writeb(val, sport->port.membase + UARTCFIFO); } -- 2.21.0 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=-9.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 589FDC4360C for ; Fri, 4 Oct 2019 21:55:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 290E2222BE for ; Fri, 4 Oct 2019 21:55:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TMYufGuS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729441AbfJDVzu (ORCPT ); Fri, 4 Oct 2019 17:55:50 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:44440 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726780AbfJDVzu (ORCPT ); Fri, 4 Oct 2019 17:55:50 -0400 Received: by mail-pg1-f195.google.com with SMTP id i14so4467658pgt.11; Fri, 04 Oct 2019 14:55:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=vkZt0GXM6qo82WWXoUdTiYWmectwUJ8fNOCzw+vFaZA=; b=TMYufGuSnVoxWfOa8/Z/yRVBCyCrAwDmi57il930HlXUOWstAn1VqNgqDpxG1/s6FO jVzxb47Maw5QTKV6BdRdm2QHqkXXajXuMft5uydWJ99ug99ePO0JfKZ7Yzs3AUFszp4z oNO2bNEo5kVLPtTCaUmeaoeLPIFKW7K5j2s9Fuvd4oV86SZ9BhW+YIDKpSPrhj7Pzr5A EQcZ5Y0bvs+1S/4dvq7NnL0CQLhxkGBTzgg6WUuRT2qhJlxsogGuTPP+NKpQ1/OdALTq O0ToFvndKTQat/q1uNOZrmIfItPPQ8GhI9SnH5APlRoQS97Uu1BT7ZfL7paW94ySCiPj CbYQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=vkZt0GXM6qo82WWXoUdTiYWmectwUJ8fNOCzw+vFaZA=; b=c2GQDB9SWaEzFF6cFO25N7vNut0AAaQLW0WQWVHoTAEG6ySsrRyjl7iIdyCQUg6mWn fZ2G0AHiV44p1StiYOMyvbrPSF4Qagq2DlRnyZWP6T5NOa/OuGmPQShFMiK2zsP0mj1o kiDMxFhkDdwQ1VWVW9Ugw/zFQZFyqLZ+eptwb74XR57MSEwJGV5SPdbyN5XkUo8mZHjP hvCxoK+b5gPwA8aW7Rc5tQC4J54e5Tk8vZoDN5lWgre3ECo3p7emIHocfsqtxshXsdpt HxEetOW+fgFjScTXxHYxKqnRZbf16JqD0+mgKgF3F/cLuUmKdGuwSENhyUjC69+3TaUu nljg== X-Gm-Message-State: APjAAAW9sgnutfhSI90DCXX+3HDRlKsIDxzhLcoZKxvK0UXe4XOY1O8Z WBtDF3AO9H3eVlUknsRao8g= X-Google-Smtp-Source: APXvYqwx/LQCYgX/lCyiMKyiW7/oppBn2dDWhtxoXzCzqXC9DuFsGT8gP6S4+j+MAh1N3GHx0oTurA== X-Received: by 2002:a17:90a:1609:: with SMTP id n9mr19150165pja.64.1570226149687; Fri, 04 Oct 2019 14:55:49 -0700 (PDT) Received: from localhost.lan (c-67-185-54-80.hsd1.wa.comcast.net. [67.185.54.80]) by smtp.gmail.com with ESMTPSA id 207sm8094732pfu.129.2019.10.04.14.55.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Oct 2019 14:55:48 -0700 (PDT) From: Andrey Smirnov To: Greg Kroah-Hartman Cc: Andrey Smirnov , Stefan Agner , Andrew Lunn , Vivien Didelot , Chris Healy , Cory Tusar , Lucas Stach , Jiri Slaby , linux-imx@nxp.com, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] tty: serial: fsl_lpuart: Fix lpuart_flush_buffer() Date: Fri, 4 Oct 2019 14:55:37 -0700 Message-Id: <20191004215537.5308-1-andrew.smirnov@gmail.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Message-ID: <20191004215537.rA8KUvhmhrA8FFk5vnMpKJJtvh0lPsg4TPDvvMfcu6o@z> Fix incorrect read-modify-write sequence in lpuart_flush_buffer() that was reading from UARTPFIFO and writing to UARTCFIFO instead of operating solely on the latter. Fixes: 9bc19af9dacb ("tty: serial: fsl_lpuart: Flush HW FIFOs in .flush_buffer") Signed-off-by: Andrey Smirnov Cc: Stefan Agner Cc: Andrew Lunn Cc: Vivien Didelot Cc: Chris Healy Cc: Cory Tusar Cc: Lucas Stach Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-imx@nxp.com Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- Greg: This bug causes occasional boot hang on 5.4-rc1 on Vybrid, so it might be good to push that for 5.4-rc2. Thanks, Andrey Sirnov drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3e17bb8a0b16..537896c4d887 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -548,7 +548,7 @@ static void lpuart_flush_buffer(struct uart_port *port) val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH; lpuart32_write(&sport->port, val, UARTFIFO); } else { - val = readb(sport->port.membase + UARTPFIFO); + val = readb(sport->port.membase + UARTCFIFO); val |= UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH; writeb(val, sport->port.membase + UARTCFIFO); } -- 2.21.0