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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 12C05C33C9E for ; Sat, 1 Feb 2020 11:59:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA3EE206E6 for ; Sat, 1 Feb 2020 11:59:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726385AbgBAL7o (ORCPT ); Sat, 1 Feb 2020 06:59:44 -0500 Received: from fieber.vanmierlo.com ([84.243.197.177]:41332 "EHLO kerio9.vanmierlo.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726297AbgBAL7o (ORCPT ); Sat, 1 Feb 2020 06:59:44 -0500 X-Greylist: delayed 1805 seconds by postgrey-1.27 at vger.kernel.org; Sat, 01 Feb 2020 06:59:43 EST X-Footer: dmFubWllcmxvLmNvbQ== Received: from roundcube.vanmierlo.com ([192.168.37.37]) (authenticated user m.brock@vanmierlo.com) by kerio9.vanmierlo.com (Kerio Connect 9.2.11 beta 1) with ESMTPA; Sat, 1 Feb 2020 12:29:15 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Sat, 01 Feb 2020 12:29:15 +0100 From: Maarten Brock To: Shubhrajyoti Datta Cc: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jslaby@suse.com, michal.simek@xilinx.com, linux-kernel@vger.kernel.org, Raviteja Narayanam , linux-serial-owner@vger.kernel.org Subject: Re: [PATCH v3] serial: uartps: Add TACTIVE bit in cdns_uart_tx_empty function In-Reply-To: <1580468685-11373-1-git-send-email-shubhrajyoti.datta@xilinx.com> References: <1580468685-11373-1-git-send-email-shubhrajyoti.datta@xilinx.com> Message-ID: <44b8cf91d3d2f20a81e0215b1b2fc7a8@vanmierlo.com> X-Sender: m.brock@vanmierlo.com User-Agent: Roundcube Webmail/1.3.3 Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On 2020-01-31 12:04, Shubhrajyoti Datta wrote: > drivers/tty/serial/xilinx_uartps.c | 22 +++++----------------- > 1 file changed, 5 insertions(+), 17 deletions(-) > > diff --git a/drivers/tty/serial/xilinx_uartps.c > b/drivers/tty/serial/xilinx_uartps.c > index ed2f325..ebd0a74 100644 > --- a/drivers/tty/serial/xilinx_uartps.c > +++ b/drivers/tty/serial/xilinx_uartps.c > @@ -656,8 +655,9 @@ static unsigned int cdns_uart_tx_empty(struct > uart_port *port) > { > unsigned int status; > > - status = readl(port->membase + CDNS_UART_SR) & > - CDNS_UART_SR_TXEMPTY; > + status = ((readl(port->membase + CDNS_UART_SR) & > + (CDNS_UART_SR_TXEMPTY | > + CDNS_UART_SR_TACTIVE)) == CDNS_UART_SR_TXEMPTY); > return status ? TIOCSER_TEMT : 0; > } These lines look pretty incomprehensible. How about rewriting it like this? status = readl(port->membase + CDNS_UART_SR) & (CDNS_UART_SR_TXEMPTY | CDNS_UART_SR_TACTIVE); return (status == CDNS_UART_SR_TXEMPTY) ? TIOCSER_TEMT : 0; Maarten