Re: 2.1.56 lp module problems

Andrea Arcangeli (
Thu, 25 Sep 1997 00:06:44 +0200 (CEST)

On Tue, 23 Sep 1997, Juhani Rautiainen wrote:

>On Mon, 22 Sep 1997, Tim Waugh wrote:
>> On Mon, 22 Sep 1997, Bernhard Rosenkraenzer wrote:
>> > Hello,
>> > Trying to modprobe lp.o for the 2.1.56 kernel hangs my system - my
>> > parallel port is the internal one of a Gigabyte TX mainboard, set to
>> > ECP/EPP mode.
>> Erk! It completely hangs? Did this happen for any other kernel
>> revisions? Is it possible to change the mode of the port to something
>> other than ECP/EPP?
>I've been trying to debug it but those faster than speed of light reboots
>and constant filesystem checks with 2 GB partition make it slow progress.

Add "while (1) udelay(1000);" before the Oops.
umount -a before trying.

>What I've found out so far is this (my machine is at home so please bear
>with me). BTW my motherboard is Asus T2P4 (haven't checked chipset yet).
>Parport_pc thinks that IRQ 8 is irq it should use. I've tracked this down
>to programmable_irq_support where irq gets value 1 from hardware probe
>(pc_read_configb()). After that parport_pc promptly does irq+=7 in switch
>block which results into irq 8. BTW it believes this more than value
>that I give with insmod parameters. I changed this so that value 1 gives
>PARPORT_IRQ_NONE. After that I could set irq with insmod. Now everything
>seemed to be fine from parport side but doing insmod ppa reboots machine
>in less than one second. I've got K6@225 and what ever scrolls on screen
>goes by so fast that it is unreadable and leaves no traces in log. Only
>thing I reliably saw was "EPP timeout" from ppa. Ppa works fine with
>2.0.30 when it does things without parport. Because there were no other
>reports of problems I thought that I dig bit deeper into this before
>reporting this.

PPA works fine just now, also sharing parport with lp using [2.1.56]. Try
the ppa patch in my homepage. I posted the ppa patch also in linux-kernel
some days ago for increase the testing. Apply the scsi_module patch too,
you can find it in linux-kernel again, the subject is [**patch**].

Andreas Arcangeli