Re: /proc/interrupts and serial

Etienne Lorrain (lorrain@fb.sony.de)
Tue, 6 Oct 1998 10:43:51 +0001

Matthias Andree <mandree@sx1.HRZ.Uni-Dortmund.DE> wrote:
> I have got four serial ports, 16550A type, which are correctly
> recognized and auto-configured (even auto_irq with 2.1.124) by the
> kernel, but the interrupts of ttyS2 and ttyS3 don't show up in
> /proc/interrupts, while their ioports do.

Only interrupts currently "allocated" show up in /proc/interrupt,
and the serial driver just "allocate" IRQ when the pseudo file
/dev/ttyS* is open - ioports are permanently reserved.
Try:
cat < /dev/ttyS2 &
cat < /dev/ttyS3 &
cat /proc/interrupt
fg ^C
fg ^C
To know the number of IRQ which have appeared, "cat /proc/sys/stat"

Etienne.

--
-- The world belong to its organizer.


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