From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:47650 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752799AbdDCMld (ORCPT ); Mon, 3 Apr 2017 08:41:33 -0400 Subject: Patch "serial: mxs-auart: Fix baudrate calculation" has been added to the 4.10-stable tree To: u.kleine-koenig@pengutronix.de, gregkh@linuxfoundation.org Cc: , From: Date: Mon, 03 Apr 2017 14:41:00 +0200 Message-ID: <1491223260102218@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled serial: mxs-auart: Fix baudrate calculation to the 4.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-mxs-auart-fix-baudrate-calculation.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From a6040bc610554c66088fda3608ae5d6307c548e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Mon, 20 Mar 2017 10:05:38 +0100 Subject: serial: mxs-auart: Fix baudrate calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Uwe Kleine-König commit a6040bc610554c66088fda3608ae5d6307c548e4 upstream. The reference manual for the i.MX28 recommends to calculate the divisor as divisor = (UARTCLK * 32) / baud rate, rounded to the nearest integer , so let's do this. For a typical setup of UARTCLK = 24 MHz and baud rate = 115200 this changes the divisor from 6666 to 6667 and so the actual baud rate improves from 115211.521 Bd (error ≅ 0.01 %) to 115194.240 Bd (error ≅ 0.005 %). Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mxs-auart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -1085,7 +1085,7 @@ static void mxs_auart_settermios(struct AUART_LINECTRL_BAUD_DIV_MAX); baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN; baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max); - div = u->uartclk * 32 / baud; + div = DIV_ROUND_CLOSEST(u->uartclk * 32, baud); } ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); Patches currently in stable-queue which might be from u.kleine-koenig@pengutronix.de are queue-4.10/serial-mxs-auart-fix-baudrate-calculation.patch