From patchwork Tue Oct 27 13:56:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 289787 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 57973C55179 for ; Tue, 27 Oct 2020 15:17:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D16E22264 for ; Tue, 27 Oct 2020 15:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603811832; bh=cgFXcNkUbl2sjPVQZk+vIt47X5S+DfvakEwJZgqpaPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tSzKOyWqH5z0paoZ4aBkMZ5gwEo4IkV17QK9iTKF/TK8zHCtuNbfDi3x4DALmoAN7 q+PjwJ2C28DOsal7aWHFpQrCY7SioEFMRKGZgZCR5peTLTev9MebrTzOly83Gkw5WW cm4G9xePMmuoTS29UcHBQicdOslEr14rkrIP6Z+Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1796289AbgJ0PRL (ORCPT ); Tue, 27 Oct 2020 11:17:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:53628 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1794621AbgJ0PQ4 (ORCPT ); Tue, 27 Oct 2020 11:16:56 -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 8729522283; Tue, 27 Oct 2020 15:16:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603811816; bh=cgFXcNkUbl2sjPVQZk+vIt47X5S+DfvakEwJZgqpaPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cwKCPFN83D20vDq+D1JWQcnQDQ9TTaix9AO6q3d3c/cNQGV63EpGoHFth0TAAdw/F wUQW9+CI5UCifaIvbL8fnxRlOoQyF5tsyVlcf23lrIqA1sjTmqS/cWw34tVIo52j8g mnOWV+BbsBtCpIbNUKEqSIbEL9uKN6tgJ9mxTkR0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Fugang Duan , Peng Fan Subject: [PATCH 5.8 627/633] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char Date: Tue, 27 Oct 2020 14:56:10 +0100 Message-Id: <20201027135552.227470076@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027135522.655719020@linuxfoundation.org> References: <20201027135522.655719020@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);