From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: 2.6.25 upgraded to 2.6.36: serial app stops working Date: Tue, 30 Nov 2010 08:42:32 -0800 Message-ID: <20101130164232.GB18017@kroah.com> References: <20101130162754.GI5654@belle.intranet.vanheusden.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from kroah.org ([198.145.64.141]:42007 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750821Ab0K3QoE (ORCPT ); Tue, 30 Nov 2010 11:44:04 -0500 Content-Disposition: inline In-Reply-To: <20101130162754.GI5654@belle.intranet.vanheusden.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: folkert Cc: linux-serial@vger.kernel.org On Tue, Nov 30, 2010 at 05:27:55PM +0100, folkert wrote: > Hi, > > I upgraded my linux system to 2.6.36. Now suddenly my serial driver for > my MSF receiver stopped working. Two things I noticed: I need to open > the serial device (/dev/ttyS0, a regular uart, see below) with O_NDELAY > for open() to return at all. Then something funny happens: I read bytes > from the device (at 50bps) which runs fine for a while but then suddenly > I get a burst of '0x00' bytes - precisely at the point at which the MSF > radio device sends a timecode! So I think the device fiddles with one of > the pins of the serial port confusing the linux serial driver. This > worked fine upto and including 2.6.25 (maybe later too) but with 2.6.36 > this fails. > Anyone an idea what might go wrong here? And how to fix it? Any chance you could use 'git bisect' on the kernel tree to see what caused the change? Moving from .25 to .36 is a huge jump, many many years of development and loads of things have changed so we need some help to narrow the problem down. thanks, greg k-h