Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 26 Oct 2001 14:00:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 26 Oct 2001 14:00:31 -0400 Received: from host154.207-175-42.redhat.com ([207.175.42.154]:7144 "EHLO lacrosse.corp.redhat.com") by vger.kernel.org with ESMTP id ; Fri, 26 Oct 2001 14:00:15 -0400 Date: Fri, 26 Oct 2001 19:00:48 +0100 From: Tim Waugh To: Dave Garry Cc: junio@siamese.dhis.twinsun.com, bill davidsen , linux-kernel@vger.kernel.org Subject: Re: [patch] Re: linux-2.4.12 / linux-2.4.13 parallel port problem Message-ID: <20011026190048.D7544@redhat.com> In-Reply-To: <20011024230917.H7544@redhat.com> <20011025165226.T7544@redhat.com> <7vofmuu9d7.fsf@siamese.dhis.twinsun.com> <20011026104125.Z7544@redhat.com> <3BD9647A.B6244D05@firsdown.demon.co.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="yprSwhkmOQmTTEHC" Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <3BD9647A.B6244D05@firsdown.demon.co.uk>; from daveg@firsdown.demon.co.uk on Fri, Oct 26, 2001 at 02:26:18PM +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --yprSwhkmOQmTTEHC Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Oct 26, 2001 at 02:26:18PM +0100, Dave Garry wrote: > I'm now running 2.4.14-pre2, still had difficulty applying > the patch, and ended up patching parport_pc.c by hand. (?) I made the patch against 2.4.14-pre2. Works for me: [tim@cyberelk linux]$ patch -p1 < /tmp/linux-irq.patch patching file drivers/parport/ChangeLog patching file drivers/parport/parport_pc.c [tim@cyberelk linux]$ grep SUBLEVEL Makefile | head -1 SUBLEVEL =3D 14 > However, loading the parport_pc module, with NO arguments, > like I was doing up till 2.4.10, and it still does not > recognise the port as being in ECP mode: As I think I've explained: without an IRQ to use, the current implementation can't use the FIFO, and so won't use hardware assistance for ECP mode. By default, parport_pc doesn't use _any_ interrupts, due to the likely conflicts it would cause (ISA soundcards, etc.). > [root@p450 /root]# modprobe parport_pc > [root@p450 /root]# dmesg -c > parport0: PC-style at 0x378 (0x778) [PCSPP,TRISTATE] > parport0: irq 7 detected So IRQ 7 is detected after you've applied the patch, whereas before it wasn't at all. The patch works. 'ECP' is not listed in brackets because hardware assistance won't be used. > If I load the module WITH arguments, something I've never > had to do in the past, it works: >=20 > [root@p450 /root]# modprobe parport_pc io=3D0x378 irq=3D7 Just use 'irq=3Dauto'. Now that the IRQ probing is fixed again, this will work. > I'm still unsure why I NEED to supply arguments to this module. The short answer is that you shouldn't have to. If I remember correctly, you just want VMware to work. VMware doesn't go through the kernel to access the port, it just writes the registers directly. But it asks the kernel what modes it is prepared to use. This is something that needs to be fixed in VMware really: if it isn't going to use the kernel for port access, it shouldn't care what modes the kernel would use if it did. If VMware is going to write to the ports directly, it should do its own probing of the port hardware. This policy isn't one of just being obstinate: the old behaviour was a bug, and differed from what parport.txt had to say about the matter. Not only that, but in order for ECP-mode printing to work properly the fixed behaviour is a necessity. (Otherwise we'd use ECP mode on ECP-able printers even when it was slower to do so!) Thanks for testing the patch. Hopefully when the PnPBIOS support is fully tested we'll be able to use whatever interrupts we find, rather than playing as safe as we do currently. Tim. */ --yprSwhkmOQmTTEHC Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE72aTQyaXy9qA00+cRAhTMAJ9cEWW3Fiyck56DmF6XFiK6ieTvRACeL5F5 M0EPsn99lDdVMUJzlj/qwYA= =0sYk -----END PGP SIGNATURE----- --yprSwhkmOQmTTEHC-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/