[PATCH 06/15] memory: jz4780-nemc: Convert to platform remove callback returning void

Uwe Kleine-König posted 15 patches 11 months ago
[PATCH 06/15] memory: jz4780-nemc: Convert to platform remove callback returning void
Posted by Uwe Kleine-König 11 months ago
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/memory/jz4780-nemc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/memory/jz4780-nemc.c b/drivers/memory/jz4780-nemc.c
index e5a93e7da15f..fb6db2ffe71b 100644
--- a/drivers/memory/jz4780-nemc.c
+++ b/drivers/memory/jz4780-nemc.c
@@ -384,12 +384,11 @@ static int jz4780_nemc_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int jz4780_nemc_remove(struct platform_device *pdev)
+static void jz4780_nemc_remove(struct platform_device *pdev)
 {
 	struct jz4780_nemc *nemc = platform_get_drvdata(pdev);
 
 	clk_disable_unprepare(nemc->clk);
-	return 0;
 }
 
 static const struct jz_soc_info jz4740_soc_info = {
@@ -408,7 +407,7 @@ static const struct of_device_id jz4780_nemc_dt_match[] = {
 
 static struct platform_driver jz4780_nemc_driver = {
 	.probe		= jz4780_nemc_probe,
-	.remove		= jz4780_nemc_remove,
+	.remove_new	= jz4780_nemc_remove,
 	.driver	= {
 		.name	= "jz4780-nemc",
 		.of_match_table = of_match_ptr(jz4780_nemc_dt_match),
-- 
2.42.0

Re: [PATCH 06/15] memory: jz4780-nemc: Convert to platform remove callback returning void
Posted by Paul Cercueil 11 months ago
Hi,

Le dimanche 17 décembre 2023 à 15:29 +0100, Uwe Kleine-König a écrit :
> The .remove() callback for a platform driver returns an int which
> makes
> many driver authors wrongly assume it's possible to do error handling
> by
> returning an error code. However the value returned is ignored (apart
> from emitting a warning) and this typically results in resource
> leaks.
> 
> To improve here there is a quest to make the remove callback return
> void. In the first step of this quest all drivers are converted to
> .remove_new(), which already returns void. Eventually after all
> drivers
> are converted, .remove_new() will be renamed to .remove().
> 
> Trivially convert this driver from always returning zero in the
> remove
> callback to the void returning variant.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Acked-by: Paul Cercueil <paul@crapouillou.net>

Cheers,
-Paul

> ---
>  drivers/memory/jz4780-nemc.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/memory/jz4780-nemc.c b/drivers/memory/jz4780-
> nemc.c
> index e5a93e7da15f..fb6db2ffe71b 100644
> --- a/drivers/memory/jz4780-nemc.c
> +++ b/drivers/memory/jz4780-nemc.c
> @@ -384,12 +384,11 @@ static int jz4780_nemc_probe(struct
> platform_device *pdev)
>  	return 0;
>  }
>  
> -static int jz4780_nemc_remove(struct platform_device *pdev)
> +static void jz4780_nemc_remove(struct platform_device *pdev)
>  {
>  	struct jz4780_nemc *nemc = platform_get_drvdata(pdev);
>  
>  	clk_disable_unprepare(nemc->clk);
> -	return 0;
>  }
>  
>  static const struct jz_soc_info jz4740_soc_info = {
> @@ -408,7 +407,7 @@ static const struct of_device_id
> jz4780_nemc_dt_match[] = {
>  
>  static struct platform_driver jz4780_nemc_driver = {
>  	.probe		= jz4780_nemc_probe,
> -	.remove		= jz4780_nemc_remove,
> +	.remove_new	= jz4780_nemc_remove,
>  	.driver	= {
>  		.name	= "jz4780-nemc",
>  		.of_match_table =
> of_match_ptr(jz4780_nemc_dt_match),