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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DF809C4363A for ; Tue, 27 Oct 2020 18:08:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8653220723 for ; Tue, 27 Oct 2020 18:08:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603822103; bh=amTksholHYaP6V3+fRmuESgR76MxgK1BjgKQ7sYOYLg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Efnnavng6hhCIh07C9mj4fg/2FKR1LYt1tFcd7QBKxSXk9NZj7tptAdhZGoEPt9as uBHRlHu0EhCzMJEOEtBnBEY5roOaW96rj6YqaIiJRTIlYfK1C/vvq6NOZm83jaf8fK QOIa3oyVBZBvTM+6nxmpyaLkEDdJE8cN+aS9gTko= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1825073AbgJ0SIW (ORCPT ); Tue, 27 Oct 2020 14:08:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:38388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2508860AbgJ0OQW (ORCPT ); Tue, 27 Oct 2020 10:16:22 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 572CF2076A; Tue, 27 Oct 2020 14:16:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603808181; bh=amTksholHYaP6V3+fRmuESgR76MxgK1BjgKQ7sYOYLg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UnuIgXFyJC8EqEr/zf68glCU1wG5WFL+qFMSeEecVMHWZaV+e5+thbI0hD06hQFOn wp7yVcdOu8uBSBF2gTlj/0QRvT/d1sJ3zo1EfdkxdGB1X/qBG9kZkDFsteOA7HpeEh uzw9W6wJFYOf/tYAvG/GYMwudUEmGaRnfwWAXXTA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Fugang Duan , Peng Fan Subject: [PATCH 4.14 187/191] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char Date: Tue, 27 Oct 2020 14:50:42 +0100 Message-Id: <20201027134918.715220865@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027134909.701581493@linuxfoundation.org> References: <20201027134909.701581493@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: Peng Fan commit 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 upstream. The watermark is set to 1, so we need to input two chars to trigger RDRF using the original logic. With the new logic, we could always get the char when there is data in FIFO. Suggested-by: Fugang Duan Signed-off-by: Peng Fan Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@nxp.com Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -567,7 +567,7 @@ static void lpuart32_poll_put_char(struc static int lpuart32_poll_get_char(struct uart_port *port) { - if (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_RDRF)) + if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF)) return NO_POLL_CHAR; return lpuart32_read(port, UARTDATA);