[Linux-parport] [PATCH] parport_pc: after superio probing restore original register values

Alan Cox alan at lxorguk.ukuu.org.uk
Mon Jun 15 17:58:26 EDT 2009

On Mon, 15 Jun 2009 19:33:52 +0200
Jens Rottmann <JRottmann at LiPPERTEmbedded.de> wrote:

> CONFIG_PARPORT_PC_SUPERIO probes for various superio chips by writing
> byte sequences to a set of different potential I/O ranges.  But the
> probed ranges are not exclusive to parallel ports.  Some of our boards
> just happen to have a watchdog in one of them.  Took us almost a week
> to figure out why some distros reboot without warning after running
> flawlessly for 3 hours.  For exactly 170 = 0xAA minutes, that is ...

Ouch - that must have been a pig to find.

> Fixed by restoring original values after probing.  Also fixed too small
> request_region() in detect_and_report_it87().
> Signed-off-by: Jens Rottmann <JRottmann at LiPPERTEmbedded.de>

Will queue for Linus


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