[v1] gpio: remove uneeded Kconfig dependencies on OF_GPIO

[PATCH 10/14] watchdog: convert the Kconfig dependency on OF_GPIO to OF

Posted by Bartosz Golaszewski 1 month, 1 week ago

OF_GPIO is selected automatically on all OF systems. Any symbols it
controls also provide stubs so there's really no reason to select it
explicitly. We could simply remove the dependency but in order to avoid
a new symbol popping up for everyone in make config - just convert it to
requiring CONFIG_OF.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/watchdog/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index dc78729ba2a5d6e035ed3cbe5c2b631d11b76b20..ef200339a22a6f9c51a46c9c0b8466add74313e2 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -250,7 +250,7 @@ config DA9062_WATCHDOG
 
 config GPIO_WATCHDOG
 	tristate "Watchdog device controlled through GPIO-line"
-	depends on OF_GPIO
+	depends on OF
 	select WATCHDOG_CORE
 	help
 	  If you say yes here you get support for watchdog device

-- 
2.47.3

Re: [PATCH 10/14] watchdog: convert the Kconfig dependency on OF_GPIO to OF

Posted by Guenter Roeck 1 month, 1 week ago

On Wed, Mar 04, 2026 at 10:02:31AM +0100, Bartosz Golaszewski wrote:
> OF_GPIO is selected automatically on all OF systems. Any symbols it

Actually, that isn't really true.

if GPIOLIB
...
config OF_GPIO
        def_bool y
        depends on OF
        depends on HAS_IOMEM

OF_GPIO also depends on GPIOLIB and HAS_IOMEM. I don't know why it needs
to depend on HAS_IOMEM, but the GPIOLIB dependency is real.

Guenter

> controls also provide stubs so there's really no reason to select it
> explicitly. We could simply remove the dependency but in order to avoid
> a new symbol popping up for everyone in make config - just convert it to
> requiring CONFIG_OF.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> ---
>  drivers/watchdog/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index dc78729ba2a5d6e035ed3cbe5c2b631d11b76b20..ef200339a22a6f9c51a46c9c0b8466add74313e2 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -250,7 +250,7 @@ config DA9062_WATCHDOG
>  
>  config GPIO_WATCHDOG
>  	tristate "Watchdog device controlled through GPIO-line"
> -	depends on OF_GPIO
> +	depends on OF
>  	select WATCHDOG_CORE
>  	help
>  	  If you say yes here you get support for watchdog device

Re: [PATCH 10/14] watchdog: convert the Kconfig dependency on OF_GPIO to OF

Posted by Guenter Roeck 1 month, 1 week ago

On Wed, Mar 04, 2026 at 10:02:31AM +0100, Bartosz Golaszewski wrote:
> OF_GPIO is selected automatically on all OF systems. Any symbols it
> controls also provide stubs so there's really no reason to select it
> explicitly. We could simply remove the dependency but in order to avoid
> a new symbol popping up for everyone in make config - just convert it to
> requiring CONFIG_OF.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> ---
>  drivers/watchdog/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index dc78729ba2a5d6e035ed3cbe5c2b631d11b76b20..ef200339a22a6f9c51a46c9c0b8466add74313e2 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -250,7 +250,7 @@ config DA9062_WATCHDOG
>  
>  config GPIO_WATCHDOG
>  	tristate "Watchdog device controlled through GPIO-line"
> -	depends on OF_GPIO
> +	depends on OF

AI feedback:

  Could this change inadvertently allow the driver to be selected when GPIOLIB
  is disabled?

  In drivers/gpio/Kconfig, OF_GPIO is defined inside the "if GPIOLIB" block,
  so it implicitly depends on GPIOLIB. By changing the dependency directly to
  OF, the GPIOLIB dependency is lost.

  If GPIOLIB is disabled, the driver will still compile because of the stubs
  in include/linux/gpio/consumer.h, but devm_gpiod_get() will unconditionally
  return -ENOSYS, causing the probe to fail. Since the driver's sole purpose
  is to control a watchdog via a GPIO line, should it be prevented from being
  configured without GPIOLIB by using something like:

	depends on OF && GPIOLIB

It has a point. Please update.

Thanks,
Guenter

>  	select WATCHDOG_CORE
>  	help
>  	  If you say yes here you get support for watchdog device

Re: [PATCH 10/14] watchdog: convert the Kconfig dependency on OF_GPIO to OF

Posted by Guenter Roeck 1 month, 1 week ago

On 3/4/26 01:02, Bartosz Golaszewski wrote:
> OF_GPIO is selected automatically on all OF systems. Any symbols it
> controls also provide stubs so there's really no reason to select it
> explicitly. We could simply remove the dependency but in order to avoid
> a new symbol popping up for everyone in make config - just convert it to
> requiring CONFIG_OF.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   drivers/watchdog/Kconfig | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index dc78729ba2a5d6e035ed3cbe5c2b631d11b76b20..ef200339a22a6f9c51a46c9c0b8466add74313e2 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -250,7 +250,7 @@ config DA9062_WATCHDOG
>   
>   config GPIO_WATCHDOG
>   	tristate "Watchdog device controlled through GPIO-line"
> -	depends on OF_GPIO
> +	depends on OF
>   	select WATCHDOG_CORE
>   	help
>   	  If you say yes here you get support for watchdog device
>