The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the need of a dedicated function used
with devm_add_action_or_reset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/watchdog/apple_wdt.c | 18 +-----------------
 1 file changed, 1 insertion(+), 17 deletions(-)

diff --git a/drivers/watchdog/apple_wdt.c b/drivers/watchdog/apple_wdt.c
index 16aca21f13d6..eddeb0fede89 100644
--- a/drivers/watchdog/apple_wdt.c
+++ b/drivers/watchdog/apple_wdt.c
@@ -136,11 +136,6 @@ static int apple_wdt_restart(struct watchdog_device *wdd, unsigned long mode,
 	return 0;
 }
 
-static void apple_wdt_clk_disable_unprepare(void *data)
-{
-	clk_disable_unprepare(data);
-}
-
 static struct watchdog_ops apple_wdt_ops = {
 	.owner = THIS_MODULE,
 	.start = apple_wdt_start,
@@ -162,7 +157,6 @@ static int apple_wdt_probe(struct platform_device *pdev)
 	struct apple_wdt *wdt;
 	struct clk *clk;
 	u32 wdt_ctrl;
-	int ret;
 
 	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
 	if (!wdt)
@@ -172,19 +166,9 @@ static int apple_wdt_probe(struct platform_device *pdev)
 	if (IS_ERR(wdt->regs))
 		return PTR_ERR(wdt->regs);
 
-	clk = devm_clk_get(dev, NULL);
+	clk = devm_clk_get_enabled(dev, NULL);
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
-
-	ret = clk_prepare_enable(clk);
-	if (ret)
-		return ret;
-
-	ret = devm_add_action_or_reset(dev, apple_wdt_clk_disable_unprepare,
-				       clk);
-	if (ret)
-		return ret;
-
 	wdt->clk_rate = clk_get_rate(clk);
 	if (!wdt->clk_rate)
 		return -EINVAL;
-- 
2.34.1

On Sat, Dec 31, 2022, at 08:57, Christophe JAILLET wrote:
> The devm_clk_get_enabled() helper:
>    - calls devm_clk_get()
>    - calls clk_prepare_enable() and registers what is needed in order to
>      call clk_disable_unprepare() when needed, as a managed resource.
>
> This simplifies the code and avoids the need of a dedicated function used
> with devm_add_action_or_reset().
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Reviewed-by: Sven Peter <sven@svenpeter.dev>


Thanks,


Sven

On Sat, Dec 31, 2022 at 08:57:22AM +0100, Christophe JAILLET wrote:
> The devm_clk_get_enabled() helper:
>    - calls devm_clk_get()
>    - calls clk_prepare_enable() and registers what is needed in order to
>      call clk_disable_unprepare() when needed, as a managed resource.
> 
> This simplifies the code and avoids the need of a dedicated function used
> with devm_add_action_or_reset().
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

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

> ---
>  drivers/watchdog/apple_wdt.c | 18 +-----------------
>  1 file changed, 1 insertion(+), 17 deletions(-)
> 
> diff --git a/drivers/watchdog/apple_wdt.c b/drivers/watchdog/apple_wdt.c
> index 16aca21f13d6..eddeb0fede89 100644
> --- a/drivers/watchdog/apple_wdt.c
> +++ b/drivers/watchdog/apple_wdt.c
> @@ -136,11 +136,6 @@ static int apple_wdt_restart(struct watchdog_device *wdd, unsigned long mode,
>  	return 0;
>  }
>  
> -static void apple_wdt_clk_disable_unprepare(void *data)
> -{
> -	clk_disable_unprepare(data);
> -}
> -
>  static struct watchdog_ops apple_wdt_ops = {
>  	.owner = THIS_MODULE,
>  	.start = apple_wdt_start,
> @@ -162,7 +157,6 @@ static int apple_wdt_probe(struct platform_device *pdev)
>  	struct apple_wdt *wdt;
>  	struct clk *clk;
>  	u32 wdt_ctrl;
> -	int ret;
>  
>  	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
>  	if (!wdt)
> @@ -172,19 +166,9 @@ static int apple_wdt_probe(struct platform_device *pdev)
>  	if (IS_ERR(wdt->regs))
>  		return PTR_ERR(wdt->regs);
>  
> -	clk = devm_clk_get(dev, NULL);
> +	clk = devm_clk_get_enabled(dev, NULL);
>  	if (IS_ERR(clk))
>  		return PTR_ERR(clk);
> -
> -	ret = clk_prepare_enable(clk);
> -	if (ret)
> -		return ret;
> -
> -	ret = devm_add_action_or_reset(dev, apple_wdt_clk_disable_unprepare,
> -				       clk);
> -	if (ret)
> -		return ret;
> -
>  	wdt->clk_rate = clk_get_rate(clk);
>  	if (!wdt->clk_rate)
>  		return -EINVAL;
> -- 
> 2.34.1
>