4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Stefan Wahren wahrenst@gmx.net
[ Upstream commit f33f5b1fd1be5f5106d16f831309648cb0f1c31d ]
Users report about the unexpected behavior for setting timeouts above 15 sec on Raspberry Pi. According to watchdog-api.rst the ioctl WDIOC_SETTIMEOUT shouldn't fail because of hardware limitations. But looking at the code shows that max_timeout based on the register value PM_WDOG_TIME_SET, which is the maximum.
Since 664a39236e71 ("watchdog: Introduce hardware maximum heartbeat in watchdog core") the watchdog core is able to handle this problem.
This fix has been tested with watchdog-test from selftests.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217374 Fixes: 664a39236e71 ("watchdog: Introduce hardware maximum heartbeat in watchdog core") Signed-off-by: Stefan Wahren wahrenst@gmx.net Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Reviewed-by: Guenter Roeck linux@roeck-us.net Link: https://lore.kernel.org/r/20231112173251.4827-1-wahrenst@gmx.net Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Wim Van Sebroeck wim@linux-watchdog.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/watchdog/bcm2835_wdt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c index e6c27b71b136..35389562177b 100644 --- a/drivers/watchdog/bcm2835_wdt.c +++ b/drivers/watchdog/bcm2835_wdt.c @@ -41,6 +41,7 @@
#define SECS_TO_WDOG_TICKS(x) ((x) << 16) #define WDOG_TICKS_TO_SECS(x) ((x) >> 16) +#define WDOG_TICKS_TO_MSECS(x) ((x) * 1000 >> 16)
struct bcm2835_wdt { void __iomem *base; @@ -137,7 +138,7 @@ static struct watchdog_device bcm2835_wdt_wdd = { .info = &bcm2835_wdt_info, .ops = &bcm2835_wdt_ops, .min_timeout = 1, - .max_timeout = WDOG_TICKS_TO_SECS(PM_WDOG_TIME_SET), + .max_hw_heartbeat_ms = WDOG_TICKS_TO_MSECS(PM_WDOG_TIME_SET), .timeout = WDOG_TICKS_TO_SECS(PM_WDOG_TIME_SET), };