From patchwork Tue Aug 19 12:14:45 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Frans Klaver X-Patchwork-Id: 4742391 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 30DBA9F377 for ; Tue, 19 Aug 2014 12:18:07 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1749920136 for ; Tue, 19 Aug 2014 12:18:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 835352014A for ; Tue, 19 Aug 2014 12:18:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752802AbaHSMRI (ORCPT ); Tue, 19 Aug 2014 08:17:08 -0400 Received: from filter1.ibarracuda.nl ([83.247.7.10]:51076 "EHLO filter1.ibarracuda.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752297AbaHSMO6 (ORCPT ); Tue, 19 Aug 2014 08:14:58 -0400 X-ASG-Debug-ID: 1408450495-0759e7416b4764040002-g9IbbW Received: from XSMCASSVR01.xsens-tech.local (rev-215.116.249.87.virtu.nl [87.249.116.215]) by filter1.ibarracuda.nl with ESMTP id Z5ZOoEtOBneVVNPo (version=TLSv1 cipher=AES128-SHA bits=128 verify=NO); Tue, 19 Aug 2014 14:14:55 +0200 (CEST) X-Barracuda-Envelope-From: Frans.Klaver@xsens.com X-Barracuda-AUTH-User: xsenscom X-Barracuda-Apparent-Source-IP: 87.249.116.215 Received: from ci00147.xsens-tech.local (172.16.11.49) by XSMCASSVR01.xsens-tech.local (192.168.0.248) with Microsoft SMTP Server id 14.3.195.1; Tue, 19 Aug 2014 14:14:54 +0200 From: Frans Klaver To: Felipe Balbi CC: Frans Klaver , Tony Lindgren , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Greg Kroah-Hartman , Alexey Pelykh , Jiri Slaby , Frans Klaver , , , , , Subject: [PATCH 1/4] tty: omap-serial: pull out calculation from baud_is_mode16 Date: Tue, 19 Aug 2014 14:14:45 +0200 X-ASG-Orig-Subj: [PATCH 1/4] tty: omap-serial: pull out calculation from baud_is_mode16 Message-ID: <1408450488-4083-2-git-send-email-frans.klaver@xsens.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1408450488-4083-1-git-send-email-frans.klaver@xsens.com> References: <1406645577-18620-1-git-send-email-frans.klaver@xsens.com> <1408450488-4083-1-git-send-email-frans.klaver@xsens.com> MIME-Version: 1.0 X-Originating-IP: [172.16.11.49] X-Barracuda-Connect: rev-215.116.249.87.virtu.nl[87.249.116.215] X-Barracuda-Start-Time: 1408450495 X-Barracuda-Encrypted: AES128-SHA X-Barracuda-URL: http://filter1.ibarracuda.nl:8000/cgi-mod/mark.cgi X-Virus-Scanned: by bsmtpd at ibarracuda.nl X-Barracuda-BRTS-Status: 1 X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using per-user scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=5.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.3.8612 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP To determine the correct divisor, we need to know the difference between the desired baud rate and the actual baud rate. The calculation for this difference is implemented twice within omap_serial_baud_is_mode16(). Pull out the calculation for easier maintenance. Signed-off-by: Frans Klaver --- drivers/tty/serial/omap-serial.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index d017cec..ae935ce 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -239,6 +239,22 @@ static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable) } /* + * Calculate the absolute difference between the desired and actual baud + * rate for the given mode. + */ +static inline int calculate_baud_abs_diff(struct uart_port *port, + unsigned int baud, unsigned int mode) +{ + unsigned int n = port->uartclk / (mode * baud); + int abs_diff = baud - (port->uartclk / (mode * n)); + + if (abs_diff < 0) + abs_diff = -abs_diff; + + return abs_diff; +} + +/* * serial_omap_baud_is_mode16 - check if baud rate is MODE16X * @port: uart port info * @baud: baudrate for which mode needs to be determined @@ -252,14 +268,8 @@ static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable) static bool serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud) { - unsigned int n13 = port->uartclk / (13 * baud); - unsigned int n16 = port->uartclk / (16 * baud); - int baudAbsDiff13 = baud - (port->uartclk / (13 * n13)); - int baudAbsDiff16 = baud - (port->uartclk / (16 * n16)); - if (baudAbsDiff13 < 0) - baudAbsDiff13 = -baudAbsDiff13; - if (baudAbsDiff16 < 0) - baudAbsDiff16 = -baudAbsDiff16; + int baudAbsDiff13 = calculate_baud_abs_diff(port, baud, 13); + int baudAbsDiff16 = calculate_baud_abs_diff(port, baud, 16); return (baudAbsDiff13 >= baudAbsDiff16); }