[PATCH 01/15] memory: brcmstb_dpfe: Convert to platform remove callback returning void

Uwe Kleine-König posted 15 patches 11 months ago
[PATCH 01/15] memory: brcmstb_dpfe: 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/brcmstb_dpfe.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index a7ab3d377206..5028467b2dc9 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -909,13 +909,11 @@ static int brcmstb_dpfe_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int brcmstb_dpfe_remove(struct platform_device *pdev)
+static void brcmstb_dpfe_remove(struct platform_device *pdev)
 {
 	struct brcmstb_dpfe_priv *priv = dev_get_drvdata(&pdev->dev);
 
 	sysfs_remove_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
-
-	return 0;
 }
 
 static const struct of_device_id brcmstb_dpfe_of_match[] = {
@@ -936,7 +934,7 @@ static struct platform_driver brcmstb_dpfe_driver = {
 		.of_match_table = brcmstb_dpfe_of_match,
 	},
 	.probe = brcmstb_dpfe_probe,
-	.remove	= brcmstb_dpfe_remove,
+	.remove_new = brcmstb_dpfe_remove,
 	.resume = brcmstb_dpfe_resume,
 };
 
-- 
2.42.0

Re: [PATCH 01/15] memory: brcmstb_dpfe: Convert to platform remove callback returning void
Posted by Markus Mayer 11 months ago
On Sun, 17 Dec 2023 at 06:30, Uwe Kleine-König
<u.kleine-koenig@pengutronix.de> wrote:
>
> 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/brcmstb_dpfe.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
> index a7ab3d377206..5028467b2dc9 100644
> --- a/drivers/memory/brcmstb_dpfe.c
> +++ b/drivers/memory/brcmstb_dpfe.c
> @@ -909,13 +909,11 @@ static int brcmstb_dpfe_probe(struct platform_device *pdev)
>         return ret;
>  }
>
> -static int brcmstb_dpfe_remove(struct platform_device *pdev)
> +static void brcmstb_dpfe_remove(struct platform_device *pdev)
>  {
>         struct brcmstb_dpfe_priv *priv = dev_get_drvdata(&pdev->dev);
>
>         sysfs_remove_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
> -
> -       return 0;
>  }
>
>  static const struct of_device_id brcmstb_dpfe_of_match[] = {
> @@ -936,7 +934,7 @@ static struct platform_driver brcmstb_dpfe_driver = {
>                 .of_match_table = brcmstb_dpfe_of_match,
>         },
>         .probe = brcmstb_dpfe_probe,
> -       .remove = brcmstb_dpfe_remove,
> +       .remove_new = brcmstb_dpfe_remove,
>         .resume = brcmstb_dpfe_resume,
>  };

Acked-by: Markus Mayer <mmayer@broadcom.com>