From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932210AbWAJNVX (ORCPT ); Tue, 10 Jan 2006 08:21:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932213AbWAJNVX (ORCPT ); Tue, 10 Jan 2006 08:21:23 -0500 Received: from sf1.taajama.com ([212.86.0.100]:16891 "EHLO sf1.taajama.com") by vger.kernel.org with ESMTP id S932210AbWAJNVX (ORCPT ); Tue, 10 Jan 2006 08:21:23 -0500 Message-ID: <43C3B4A7.1000501@usr.fi> Date: Tue, 10 Jan 2006 15:20:39 +0200 From: Miika Keskinen User-Agent: Mozilla Thunderbird 1.0.7 (X11/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: serial port, custom divisor X-Enigmail-Version: 0.93.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi I read from the Documentation/serial/driver that the custom divisor is only applied to ports that have baud 38400. I'm asking if there is some reason why custom divisor should not be used for other speeds too? I do have a MIPS-SoC that does have 16550A-type uart but it needs custom divisor, no matter what the speed is. The custom divisor is calculated as follows: baud = speed of port system_frequency is in MHz cdiv = (system_frequency * 5000) / baud; if ((cdiv % 16)>7) cdiv += 8; cdiv /= 16; What I'm doing is to use early_serial_setup with flags containing ASYNC_SPD_CUST and cdiv as .custom_divisor. However the serial_core doesn't apply that divisor unless the speed is 38400 (and for example I mostly need to run it in 9600). I'm now asking if I've misunderstood something or does the removal of baud==38400 from serial_core cause problems with other architectures? btw. I'm not subscribed to the list so please cc me if replying. yours, Miika -- All bugs added by me :)