[PATCH v2] watchdog: atcwdt200: fix return value when watchdog is enabled

[PATCH v2] watchdog: atcwdt200: fix return value when watchdog is enabled

[kr494167]

From: Surendra Singh Chouhan <kr494167@gmail.com>

atcwdt_get_int_timer_type() returned TMR_UNKNOWN (enum value 3) when
CTRL_WDT_EN was set in the control register.

Because atcwdt_probe() checks "ret = atcwdt_get_int_timer_type(drv_data);
if (ret) return ret;", returning TMR_UNKNOWN caused probe() to return 3
instead of a valid negative error code.

Fix this by returning -EBUSY via dev_err_probe() when the watchdog is
already enabled and update the kernel-doc description accordingly.

Fixes: e4e0848ad046 ("watchdog: atcwdt200: Add driver for Andes ATCWDT200")
Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>
---
 drivers/watchdog/atcwdt200_wdt.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/watchdog/atcwdt200_wdt.c b/drivers/watchdog/atcwdt200_wdt.c
index 8e3b18aea368..7e757c217b0b 100644
--- a/drivers/watchdog/atcwdt200_wdt.c
+++ b/drivers/watchdog/atcwdt200_wdt.c
@@ -260,9 +260,9 @@ static void atcwdt_get_timeout_params(struct atcwdt_drv *drv_data,
  * register to determine the interrupt timer type supported by the hardware.
  *
  * Note: This function must only be called when the ATCWDT200 watchdog is
- * disabled. If the watchdog is enabled, this function returns TMR_UNKNOWN.
+ * disabled. If the watchdog is enabled, this function returns -EBUSY.
  *
- * Returns: The interrupt timer type supported by the hardware.
+ * Returns: 0 on success or negative error code on failure.
  */
 static int atcwdt_get_int_timer_type(struct atcwdt_drv *drv_data)
 {
@@ -274,7 +274,8 @@ static int atcwdt_get_int_timer_type(struct atcwdt_drv *drv_data)
 	regmap_read(drv_data->regmap, REG_CTRL, &val);
 	if (val & CTRL_WDT_EN) {
 		spin_unlock(&drv_data->lock);
-		return TMR_UNKNOWN;
+		return dev_err_probe(dev, -EBUSY,
+				     "Watchdog is enabled, cannot detect timer type\n");
 	}
 
 	/*
-- 
2.55.0

Re: [PATCH v2] watchdog: atcwdt200: fix return value when watchdog is enabled

[Guenter Roeck]

On 7/22/26 19:26, kr494167@gmail.com wrote:
> From: Surendra Singh Chouhan <kr494167@gmail.com>
> 
> atcwdt_get_int_timer_type() returned TMR_UNKNOWN (enum value 3) when
> CTRL_WDT_EN was set in the control register.
> 
> Because atcwdt_probe() checks "ret = atcwdt_get_int_timer_type(drv_data);
> if (ret) return ret;", returning TMR_UNKNOWN caused probe() to return 3
> instead of a valid negative error code.
> 
> Fix this by returning -EBUSY via dev_err_probe() when the watchdog is
> already enabled and update the kernel-doc description accordingly.
> 
> Fixes: e4e0848ad046 ("watchdog: atcwdt200: Add driver for Andes ATCWDT200")
> Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>
> ---]

Change log goes here. Do you really expect me to look up the patch history
to figure out what changed from v1 ?

Sure, this one was recent enough that I happen to remember, but
I seriously fail to understand why people can't be bothered to
add a couple of lines here to explain the changes they made.

Guenter

>   drivers/watchdog/atcwdt200_wdt.c | 7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/watchdog/atcwdt200_wdt.c b/drivers/watchdog/atcwdt200_wdt.c
> index 8e3b18aea368..7e757c217b0b 100644
> --- a/drivers/watchdog/atcwdt200_wdt.c
> +++ b/drivers/watchdog/atcwdt200_wdt.c
> @@ -260,9 +260,9 @@ static void atcwdt_get_timeout_params(struct atcwdt_drv *drv_data,
>    * register to determine the interrupt timer type supported by the hardware.
>    *
>    * Note: This function must only be called when the ATCWDT200 watchdog is
> - * disabled. If the watchdog is enabled, this function returns TMR_UNKNOWN.
> + * disabled. If the watchdog is enabled, this function returns -EBUSY.
>    *
> - * Returns: The interrupt timer type supported by the hardware.
> + * Returns: 0 on success or negative error code on failure.
>    */
>   static int atcwdt_get_int_timer_type(struct atcwdt_drv *drv_data)
>   {
> @@ -274,7 +274,8 @@ static int atcwdt_get_int_timer_type(struct atcwdt_drv *drv_data)
>   	regmap_read(drv_data->regmap, REG_CTRL, &val);
>   	if (val & CTRL_WDT_EN) {
>   		spin_unlock(&drv_data->lock);
> -		return TMR_UNKNOWN;
> +		return dev_err_probe(dev, -EBUSY,
> +				     "Watchdog is enabled, cannot detect timer type\n");
>   	}
>   
>   	/*

Re: [PATCH v2] watchdog: atcwdt200: fix return value when watchdog is enabled

[Guenter Roeck]

On Thu, Jul 23, 2026 at 07:56:34AM +0530, kr494167@gmail.com wrote:
> From: Surendra Singh Chouhan <kr494167@gmail.com>
> 
> atcwdt_get_int_timer_type() returned TMR_UNKNOWN (enum value 3) when
> CTRL_WDT_EN was set in the control register.
> 
> Because atcwdt_probe() checks "ret = atcwdt_get_int_timer_type(drv_data);
> if (ret) return ret;", returning TMR_UNKNOWN caused probe() to return 3
> instead of a valid negative error code.
> 
> Fix this by returning -EBUSY via dev_err_probe() when the watchdog is
> already enabled and update the kernel-doc description accordingly.
> 
> Fixes: e4e0848ad046 ("watchdog: atcwdt200: Add driver for Andes ATCWDT200")
> Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>

Applied. Next time please provide a change log.

Guenter