[PATCH] watchdog: davinci: Use div64_ul instead of do_div

From: cgel . zte
Date: Wed Nov 24 2021 - 21:10:20 EST


From: Changcheng Deng <deng.changcheng@xxxxxxxxxx>

do_div() does a 64-by-32 division. Here the divisor is an unsigned long
which on some platforms is 64 bit wide. So use div64_ul instead of do_div
to avoid a possible truncation.

Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
Signed-off-by: Changcheng Deng <deng.changcheng@xxxxxxxxxx>
---
drivers/watchdog/davinci_wdt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
index e6eaba6bae5b..584a56893b81 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -134,7 +134,7 @@ static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd)
timer_counter = ioread32(davinci_wdt->base + TIM12);
timer_counter |= ((u64)ioread32(davinci_wdt->base + TIM34) << 32);

- do_div(timer_counter, freq);
+ timer_counter = div64_ul(timer_counter, freq);

return wdd->timeout - timer_counter;
}
--
2.25.1