From patchwork Tue Oct 27 13:56:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 307413 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 84F1DC5DF9D for ; Tue, 27 Oct 2020 16:01:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D34520829 for ; Tue, 27 Oct 2020 16:01:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603814509; bh=cgFXcNkUbl2sjPVQZk+vIt47X5S+DfvakEwJZgqpaPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c3c8vJCraKMhKGgeUYy4GkotL7AXgFHMatYpPrrpmjNHDZfyAooAOq0NLy/szhFHP unsvNRSrPecHnf3kUyZy1Z0e8Xd/QnXGO18iU8fWBP3n2Vpb8wkqce554REvjoEJyf W00/h9Eb1wvUp7pX1o66OSnPG4vo1pW9lBUx48p4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S369014AbgJ0P7f (ORCPT ); Tue, 27 Oct 2020 11:59:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:56322 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1804286AbgJ0PyZ (ORCPT ); Tue, 27 Oct 2020 11:54:25 -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 A4349204EF; Tue, 27 Oct 2020 15:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603814065; bh=cgFXcNkUbl2sjPVQZk+vIt47X5S+DfvakEwJZgqpaPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hjam3e8NB+IZlUptbmnYsrTLdXKR0BfRz+eQcfvOSukWdBsT7cuTTJZJyEMOMvhlw 4hEeGOFuWDfk+5BmJkB4iraIs0Ak+Vl6LoqH8Ccv8odhgW0/H6VeJdLLs4wWfJZFy6 uzTx0UhPsOglpOLMv11EAL6dsA928wexKCDQHacA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Fugang Duan , Peng Fan Subject: [PATCH 5.9 751/757] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char Date: Tue, 27 Oct 2020 14:56:41 +0100 Message-Id: <20201027135525.744370238@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027135450.497324313@linuxfoundation.org> References: <20201027135450.497324313@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -680,7 +680,7 @@ 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);