From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 22 Mar 2003 15:29:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 22 Mar 2003 15:29:58 -0500 Received: from newglider.melbpc.org.au ([203.12.152.9]:54283 "EHLO relay9.melbpc.org.au") by vger.kernel.org with ESMTP id ; Sat, 22 Mar 2003 15:29:57 -0500 Message-ID: <3E7CC836.4000707@melbpc.org.au> Date: Sun, 23 Mar 2003 07:31:50 +1100 From: Tim Josling Organization: Melbourne PC User Group User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20020830 X-Accept-Language: en, en-us MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Linux Kernel List , Philip.Blundell@pobox.com, linux-parport@torque.net Subject: Re: [PATCH] to drivers/parport/ieee1284_ops.c to fix timing dependent hang References: <3E782567.3020008@melbpc.org.au> <1048278154.6017.2.camel@ixodes.goop.org> <3E7C2BA0.4040100@melbpc.org.au> <1048355094.8537.11.camel@ixodes.goop.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-RAVMilter-Version: 8.3.4(snapshot 20020706) (relay9) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > On Sat, 2003-03-22 at 01:23, Tim Josling wrote: > >>According to my reading of the code, it should only happen in polled >>mode, but I have only one week of experience looking at kernel source. > > > I'm wondering if a better fix might be to have something like: > > if (wait * 2 > wait) > wait *= 2; > > at the bottom of the loop, so that the wrap-around doesn't happen. > I tried wait *=2; if (wait > 10 * HZ) wait = 10 * HZ; and that worked, so your theory would probably work. However to my mind it is a hack. > >>So it should be a work-around, assuming interrupts work on the parallel >>port on your system :-). It is an very vexing problem, as I'm sure you know. >> >>By the way, LJ1100s tend to get page feeding problems about the time the >>warranty runs out, but HP has a free kit you can order to fix the problem. > > > Yes, I just installed it. It suddenly made the printer useful again, so > I've printing more, and seeing the hangs. I enabled interrupts, which > seems to work OK. > > J Good. That (enabling interrupts fixes the problem) tends to add credence to my theory. Happy printing! Tim Josling