[PATCH][WATCHDOG] v2.6.25-rc7: it8712f_wdt.c contains an error -was Re: [WATCHDOG] v2.5.25-rc patches

[Oliver Schuster]

Hi,

i've mailed before to lkml and Andrew Paprocki (2008-03-12) directly.
But the original patch wasn't changed. Here's a patch to correct the
error.

Description of the error:
By introducing the support of 16 Bit timer values for later it8712 an
error was made. The value is stored through superio_outw() which cause,
that the upper Byte is in the Register called "Watch Dog Timer Time-Out
Value (LSB) Register" and the lower in "Watch Dog Timer Time-Out Value
(MSB) Register".

A common value is 60: stored this way the watchdog timer runs out
in 4h 16mins. In case of a deadlocked server this is a long time to
wait, before the service comes back!

Regards,
Oliver

Wim Van Sebroeck schrieb:
> Hi Oliver,
>
> > this patch can cause serious problems in the case, that someone use it 
> > with an it8712 rev. 8 and above.
> ...
> > Your patch changes it8712f_wdt.c in function t8712f_wdt_update_margin():
> >
> > > -	superio_outb((margin > 255) ? (margin / 60) : margin, WDT_TIMEOUT);
> > > +	if (revision >= 0x08)
> > > +		superio_outw(units, WDT_TIMEOUT);
> > > +	else
> > > +		superio_outb(units, WDT_TIMEOUT);
> > but here you can't use superio_outw, because the bytes are swapped 
> > --historical reason.
> >
> > I suggest to substitute
> > 	superio_outw(units, WDT_TIMEOUT);
> > with
> > 	superio_outb(units >> 8, WDT_TIMEOUT + 1);
> > 	superio_outb(units, WDT_TIMEOUT);
>
> Can you keep "Andrew Paprocki" <andrew@xxxxxxxxxxx> in the loop?
> Can you also create a patch and test it together with Andrew?
> We need to make sure that we fix this before 2.6.25 is there.
>
> Thanks,
> Wim


This patch corrects an error in the driver it8712f_wdt

Signed-off-by: Oliver Schuster <olivers137@xxxxxxx>

===

diff -urP linux-2.6.25-rc7/drivers/watchdog/it8712f_wdt.c linux-2.6.25-rc7-aaa/drivers/watchdog/it8712f_wdt.c
--- linux-2.6.25-rc7/drivers/watchdog/it8712f_wdt.c	2008-03-26 02:38:14.000000000 +0100
+++ linux-2.6.25-rc7-aaa/drivers/watchdog/it8712f_wdt.c	2008-04-01 16:45:22.396931807 +0200
@@ -111,15 +111,6 @@
 	return val;
 }
 
-static void
-superio_outw(int val, int reg)
-{
-	outb(reg++, REG);
-	outb((val >> 8) & 0xff, VAL);
-	outb(reg, REG);
-	outb(val & 0xff, VAL);
-}
-
 static inline void
 superio_select(int ldn)
 {
@@ -170,9 +161,8 @@
 	superio_outb(config, WDT_CONFIG);
 
 	if (revision >= 0x08)
-		superio_outw(units, WDT_TIMEOUT);
-	else
-		superio_outb(units, WDT_TIMEOUT);
+		superio_outb(units >> 8, WDT_TIMEOUT + 1);
+	superio_outb(units, WDT_TIMEOUT);
 }
 
 static int