Portwell EC does not disable the watchdog during suspend. To avoid unwanted
resets, this patch adds suspend and resume callbacks (pwec_suspend() and
pwec_resume()) to the driver.

The watchdog is stopped in pwec_suspend() and restarted in pwec_resume() if
it was active before suspend.

Signed-off-by: Yen-Chi Huang <jesse.huang@portwell.com.tw>
---
 drivers/platform/x86/portwell-ec.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/platform/x86/portwell-ec.c b/drivers/platform/x86/portwell-ec.c
index 3e019c51913e..7f473e3032e2 100644
--- a/drivers/platform/x86/portwell-ec.c
+++ b/drivers/platform/x86/portwell-ec.c
@@ -246,11 +246,29 @@ static int pwec_probe(struct platform_device *pdev)
 	return 0;
 }
 
+static int pwec_suspend(struct platform_device *pdev, pm_message_t message)
+{
+	if (watchdog_active(&ec_wdt_dev))
+		return pwec_wdt_stop(&ec_wdt_dev);
+
+	return 0;
+}
+
+static int pwec_resume(struct platform_device *pdev)
+{
+	if (watchdog_active(&ec_wdt_dev))
+		return pwec_wdt_start(&ec_wdt_dev);
+
+	return 0;
+}
+
 static struct platform_driver pwec_driver = {
 	.driver = {
 		.name = "portwell-ec",
 	},
 	.probe = pwec_probe,
+	.suspend = pm_ptr(pwec_suspend),
+	.resume = pm_ptr(pwec_resume),
 };
 
 static struct platform_device *pwec_dev;
-- 
2.34.1

On Mon, 28 Jul 2025, Yen-Chi Huang wrote:

> Portwell EC does not disable the watchdog during suspend. To avoid unwanted
> resets, this patch adds suspend and resume callbacks (pwec_suspend() and
> pwec_resume()) to the driver.
> 
> The watchdog is stopped in pwec_suspend() and restarted in pwec_resume() if
> it was active before suspend.
> 
> Signed-off-by: Yen-Chi Huang <jesse.huang@portwell.com.tw>
> ---
>  drivers/platform/x86/portwell-ec.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/platform/x86/portwell-ec.c b/drivers/platform/x86/portwell-ec.c
> index 3e019c51913e..7f473e3032e2 100644
> --- a/drivers/platform/x86/portwell-ec.c
> +++ b/drivers/platform/x86/portwell-ec.c
> @@ -246,11 +246,29 @@ static int pwec_probe(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static int pwec_suspend(struct platform_device *pdev, pm_message_t message)
> +{
> +	if (watchdog_active(&ec_wdt_dev))
> +		return pwec_wdt_stop(&ec_wdt_dev);
> +
> +	return 0;
> +}
> +
> +static int pwec_resume(struct platform_device *pdev)
> +{
> +	if (watchdog_active(&ec_wdt_dev))
> +		return pwec_wdt_start(&ec_wdt_dev);
> +
> +	return 0;
> +}
> +
>  static struct platform_driver pwec_driver = {
>  	.driver = {
>  		.name = "portwell-ec",
>  	},
>  	.probe = pwec_probe,
> +	.suspend = pm_ptr(pwec_suspend),
> +	.resume = pm_ptr(pwec_resume),

These are legacy handlers, please use .pm under .driver and the macros to 
create the struct dev_pm_ops.

-- 
 i.

On 8/19/2025 5:51 PM, Ilpo Jarvinen wrote:
> On Mon, 28 Jul 2025, Yen-Chi Huang wrote:
>>  static struct platform_driver pwec_driver = {
>>  	.driver = {
>>  		.name = "portwell-ec",
>>  	},
>>  	.probe = pwec_probe,
>> +	.suspend = pm_ptr(pwec_suspend),
>> +	.resume = pm_ptr(pwec_resume),
> 
> These are legacy handlers, please use .pm under .driver and the macros to 
> create the struct dev_pm_ops.
> 

Hi Ilpo,

Thanks for pointing this out. For v4, I have switched to .pm with
DEFINE_SIMPLE_DEV_PM_OPS as suggested.

Best regards,
Yen-Chi