lkml.org 
[lkml]   [2001]   [Oct]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectBug in request_irq() ?

Hi developers,

I have some NetMos card here: 2 parallel ports, PCI.

This card is somewhat funny. I believe it fires interrupts for nothing: I
cannot boot Win98 when the Lexmark 4039 is turned on which is connected to
one of the ports (it crashes).

Back to Linux (2.4.12, "ECP symbol name patch"):

When I configure the card to share the IRQ line with the NE2000 PCI
clone, then the machine hangs as soon as the card is "ifconfig"ed.

When I configure the card to share the IRQ line with the onboard USB, then
the machine hangs as soon as the USB driver is initialized.

When I configure the card to be have an own un-shared interrupt line, and
let the NE2000clone and USB share a line, all works well.

Remember, there is no registered interrupt driver for PCI parallel port
cards. I suspect request_irq() has a problem when a device wants to
get an IRQ sharing it with a device that fires interrupts but has no own
driver.

A work-around could be disabling interrupts in the parallel port driver,
but that would mean it has to be initialized before all the other devices
sharing the IRQ --- which is prone to errors.


This is all based on more observation than code-reading so there might be
a better explanation: only I don't know it, yet.


Greetings,
Enver

-
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/

\
 
 \ /
  Last update: 2005-03-22 13:08    [W:0.046 / U:5.356 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site