[PATCH v3 RESEND 2/5] watchdog: s3c2410_wdt: Fix max_timeout being calculated larger
From: Sangwook Shin <hidden>
Date: 2025-07-14 05:59:00
Also in:
linux-samsung-soc, linux-watchdog, lkml
Subsystem:
arm/samsung s3c, s5p and exynos arm architectures, the rest, watchdog device drivers · Maintainers:
Krzysztof Kozlowski, Peter Griffin, Linus Torvalds, Wim Van Sebroeck, Guenter Roeck
Fix the issue of max_timeout being calculated larger than actual value. The calculation result of freq / (S3C2410_WTCON_PRESCALE_MAX + 1) / S3C2410_WTCON_MAXDIV is smaller than the actual value because the remainder is discarded during the calculation process. This leads to a larger calculated value for max_timeout compared to the actual settable value. A ceiling operation is applied in the calculation process to resolve this. Signed-off-by: Sangwook Shin <redacted> --- drivers/watchdog/s3c2410_wdt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 95f7207e390a..31f7e1ec779e 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c@@ -411,8 +411,8 @@ static inline unsigned int s3c2410wdt_max_timeout(struct s3c2410_wdt *wdt) { const unsigned long freq = s3c2410wdt_get_freq(wdt); - return S3C2410_WTCNT_MAXCNT / (freq / (S3C2410_WTCON_PRESCALE_MAX + 1) - / S3C2410_WTCON_MAXDIV); + return S3C2410_WTCNT_MAXCNT / DIV_ROUND_UP(freq, + (S3C2410_WTCON_PRESCALE_MAX + 1) * S3C2410_WTCON_MAXDIV); } static int s3c2410wdt_disable_wdt_reset(struct s3c2410_wdt *wdt, bool mask)
--
2.25.1