From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Lawyer Subject: Re: Serial/Parallel conflicts Date: Sat, 22 Feb 2003 23:41:12 -0800 Sender: linux-serial-owner@vger.kernel.org Message-ID: <20030223074112.GA374@lafn.org> References: <20030129170750.GA1066@wheat.boylan.org> <20030131055640.GA763@wheat.boylan.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from localhost (mail@host-66-81-197-159.rev.o1.com [66.81.197.159]) by zoon.lafn.org (8.12.3/8.11.3) with ESMTP id h1N8Ej9D059803 for ; Sun, 23 Feb 2003 00:14:45 -0800 (PST) (envelope-from dave@lafn.org) Received: from dave by localhost with local (Exim 3.36 #1 (Debian)) id 18mql6-00006l-00 for ; Sat, 22 Feb 2003 23:41:12 -0800 Content-Disposition: inline In-Reply-To: <20030131055640.GA763@wheat.boylan.org> List-Id: linux-serial@vger.kernel.org To: linux-serial@vger.kernel.org On Thu, Jan 30, 2003 at 09:56:40PM -0800, Ross Boylan wrote: > This is kind of a "please tell me it isn't so message." > My efforts to dislodge ttyS2 (aka COM3, my internal modem) from IRQ 5 > have been unsuccessful. The BIOS offers no direct control over it, > since it is not a built in serial port. > > In particular, neither of the following worked, even with reboots: > 1. reprogramming the card via /proc/isapnp. If I set the IRQ to a > value other than shown in the dmesg start up, I can't communicate with > the modem at all. This doesn't make any sense to me, since the serial > port is actually part of the card (as I understand it), and presumably > is reprogrammed by isapnp. You need to use setserial to tell the driver what isapnp set it to. isapnp doesn't tell the driver how you set the IRQ. > > Is the problem that the serial driver can not adjust to changes in > port locations after start up? Yes and no. It's yes after the the phase is completed where the driver tries to detect the serial ports by PnP methods. > > 2. I set the BIOS manually to use IRQ 5 for the parallel port. I > thought this would force it to put ttyS2 elsewhere, but it doesn't > seem to. The good news is that both the modem and the parallel port > appear to work sharing the same interrupt, so I may have symptomatic > relief. > > 3. I also disabled COM1 in BIOS, hoping to get the system to use the > newly available interrupt. It put one of the ethernet cards there > (IRQ4). > > Anyway, please tell me this info isn't just buried in the ESCD with no > way to kick it out short of flashing the whole thing! Isn't there > some other way to influence it? Is the full story "ESCD sets > location; serial driver reads it; nothing changes it"? One thing you might try is to tell the BIOS that you have a PnP OS and then whatever is in the ESCD will be ignored. David Lawyer