[PATCH] watchdog: gpio_wdt: use __udelay() to avoid recursion
Rasmus Villemoes
rasmus.villemoes at prevas.dk
Tue Sep 27 09:45:44 CEST 2022
The udelay() function in lib/time.c contains a WATCHDOG_RESET()
call. The only reason this doesn't lead to a catastrophic infinite
recursion is due to the rate-limiting in wdt-uclass.c:
if (time_after_eq(now, priv->next_reset)) {
priv->next_reset = now + priv->reset_period;
wdt_reset(dev);
}
But this would fall apart if ->next_reset was updated after calling the
device's reset method.
This is needlessly fragile, and it's easy enough to avoid that
recursion in the first place by just using __udelay() directly.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
---
drivers/watchdog/gpio_wdt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
index fe06ec8cc9..2920c2c751 100644
--- a/drivers/watchdog/gpio_wdt.c
+++ b/drivers/watchdog/gpio_wdt.c
@@ -31,7 +31,7 @@ static int gpio_wdt_reset(struct udevice *dev)
case HW_ALGO_LEVEL:
/* Pulse */
dm_gpio_set_value(&priv->gpio, 1);
- udelay(1);
+ __udelay(1);
dm_gpio_set_value(&priv->gpio, 0);
break;
}
--
2.37.2
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