| Message ID | 20230301113702.76437-1-wangwensheng4@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [-next] watchdog: sbsa: Test WDOG_HW_RUNNING bit in suspend and resume | expand |
On 3/1/23 03:37, Wang Wensheng wrote: > If the sbsa_gwdt is enabled by BIOS, the kernel set WDOG_HW_RUNNING bit > and keep it alive before anyone else would open it. When system suspend, > the sbsa_gwdt would not be disabled because WDOG_ACTIVE is not set. Then > the sbsa_gwdt would reach timeout since no one touch it during system > suspend. > > To solve this, just test WDOG_HW_RUNNING bit in suspend and disable the > sbsa_gwdt if the bit is set, then reopen it accordingly in resume > process. > > Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> > --- > drivers/watchdog/sbsa_gwdt.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c > index 9791c74aebd4..60875a710e43 100644 > --- a/drivers/watchdog/sbsa_gwdt.c > +++ b/drivers/watchdog/sbsa_gwdt.c > @@ -360,7 +360,7 @@ static int __maybe_unused sbsa_gwdt_suspend(struct device *dev) > { > struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); > > - if (watchdog_active(&gwdt->wdd)) > + if (watchdog_hw_running(&gwdt->wdd)) > sbsa_gwdt_stop(&gwdt->wdd); That will not stop the watchdog if it is currently open (active) and if it wasn't running when the module was loaded. Guenter > > return 0; > @@ -371,7 +371,7 @@ static int __maybe_unused sbsa_gwdt_resume(struct device *dev) > { > struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); > > - if (watchdog_active(&gwdt->wdd)) > + if (watchdog_hw_running(&gwdt->wdd)) > sbsa_gwdt_start(&gwdt->wdd); > > return 0;
On 3/4/23 06:54, Guenter Roeck wrote: > On 3/1/23 03:37, Wang Wensheng wrote: >> If the sbsa_gwdt is enabled by BIOS, the kernel set WDOG_HW_RUNNING bit >> and keep it alive before anyone else would open it. When system suspend, >> the sbsa_gwdt would not be disabled because WDOG_ACTIVE is not set. Then >> the sbsa_gwdt would reach timeout since no one touch it during system >> suspend. >> >> To solve this, just test WDOG_HW_RUNNING bit in suspend and disable the >> sbsa_gwdt if the bit is set, then reopen it accordingly in resume >> process. >> >> Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> >> --- >> drivers/watchdog/sbsa_gwdt.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c >> index 9791c74aebd4..60875a710e43 100644 >> --- a/drivers/watchdog/sbsa_gwdt.c >> +++ b/drivers/watchdog/sbsa_gwdt.c >> @@ -360,7 +360,7 @@ static int __maybe_unused sbsa_gwdt_suspend(struct device *dev) >> { >> struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); >> - if (watchdog_active(&gwdt->wdd)) >> + if (watchdog_hw_running(&gwdt->wdd)) >> sbsa_gwdt_stop(&gwdt->wdd); > > That will not stop the watchdog if it is currently open (active) > and if it wasn't running when the module was loaded. > I just sent a patch which fixes the problem in the watchdog core. Guenter > Guenter > >> return 0; >> @@ -371,7 +371,7 @@ static int __maybe_unused sbsa_gwdt_resume(struct device *dev) >> { >> struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); >> - if (watchdog_active(&gwdt->wdd)) >> + if (watchdog_hw_running(&gwdt->wdd)) >> sbsa_gwdt_start(&gwdt->wdd); >> return 0; >
On 3/1/23 03:37, Wang Wensheng wrote: > If the sbsa_gwdt is enabled by BIOS, the kernel set WDOG_HW_RUNNING bit > and keep it alive before anyone else would open it. When system suspend, > the sbsa_gwdt would not be disabled because WDOG_ACTIVE is not set. Then > the sbsa_gwdt would reach timeout since no one touch it during system > suspend. > > To solve this, just test WDOG_HW_RUNNING bit in suspend and disable the > sbsa_gwdt if the bit is set, then reopen it accordingly in resume > process. > > Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Prerequisite: "watchdog: core: Always set WDOG_HW_RUNNING when starting watchdog" Guenter > --- > drivers/watchdog/sbsa_gwdt.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c > index 9791c74aebd4..60875a710e43 100644 > --- a/drivers/watchdog/sbsa_gwdt.c > +++ b/drivers/watchdog/sbsa_gwdt.c > @@ -360,7 +360,7 @@ static int __maybe_unused sbsa_gwdt_suspend(struct device *dev) > { > struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); > > - if (watchdog_active(&gwdt->wdd)) > + if (watchdog_hw_running(&gwdt->wdd)) > sbsa_gwdt_stop(&gwdt->wdd); > > return 0; > @@ -371,7 +371,7 @@ static int __maybe_unused sbsa_gwdt_resume(struct device *dev) > { > struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); > > - if (watchdog_active(&gwdt->wdd)) > + if (watchdog_hw_running(&gwdt->wdd)) > sbsa_gwdt_start(&gwdt->wdd); > > return 0;
diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c index 9791c74aebd4..60875a710e43 100644 --- a/drivers/watchdog/sbsa_gwdt.c +++ b/drivers/watchdog/sbsa_gwdt.c @@ -360,7 +360,7 @@ static int __maybe_unused sbsa_gwdt_suspend(struct device *dev) { struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); - if (watchdog_active(&gwdt->wdd)) + if (watchdog_hw_running(&gwdt->wdd)) sbsa_gwdt_stop(&gwdt->wdd); return 0; @@ -371,7 +371,7 @@ static int __maybe_unused sbsa_gwdt_resume(struct device *dev) { struct sbsa_gwdt *gwdt = dev_get_drvdata(dev); - if (watchdog_active(&gwdt->wdd)) + if (watchdog_hw_running(&gwdt->wdd)) sbsa_gwdt_start(&gwdt->wdd); return 0;
If the sbsa_gwdt is enabled by BIOS, the kernel set WDOG_HW_RUNNING bit and keep it alive before anyone else would open it. When system suspend, the sbsa_gwdt would not be disabled because WDOG_ACTIVE is not set. Then the sbsa_gwdt would reach timeout since no one touch it during system suspend. To solve this, just test WDOG_HW_RUNNING bit in suspend and disable the sbsa_gwdt if the bit is set, then reopen it accordingly in resume process. Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> --- drivers/watchdog/sbsa_gwdt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)