diff mbox series

[net-next,v2,2/4] net: ethernet: ti: cpsw: Convert to platform remove callback returning void

Message ID 20231128173823.867512-3-u.kleine-koenig@pengutronix.de (mailing list archive)
State Accepted
Commit 7ac3f867a35833a228b1bd9645a1581c808a5900
Delegated to: Netdev Maintainers
Headers show
Series net: ethernet: Convert to platform remove callback returning void | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/codegen success Generated files up to date
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1115 this patch: 1115
netdev/cc_maintainers warning 2 maintainers not CCed: alexanderduyck@fb.com gerhard@engleder-embedded.com
netdev/build_clang success Errors and warnings before: 1142 this patch: 1142
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1142 this patch: 1142
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 38 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Uwe Kleine-König Nov. 28, 2023, 5:38 p.m. UTC
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().

Replace the error path returning a non-zero value by an error message
and a comment that there is more to do. With that this patch results in
no change of behaviour in this driver apart from improving the error
message.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/net/ethernet/ti/cpsw.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

Comments

Roger Quadros Nov. 30, 2023, 9:37 a.m. UTC | #1
On 28/11/2023 19:38, Uwe Kleine-König 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().
> 
> Replace the error path returning a non-zero value by an error message
> and a comment that there is more to do. With that this patch results in
> no change of behaviour in this driver apart from improving the error
> message.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Reviewed-by: Roger Quadros <rogerq@kernel.org>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index ca4d4548f85e..ea85c6dd5484 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1722,14 +1722,20 @@  static int cpsw_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int cpsw_remove(struct platform_device *pdev)
+static void cpsw_remove(struct platform_device *pdev)
 {
 	struct cpsw_common *cpsw = platform_get_drvdata(pdev);
 	int i, ret;
 
 	ret = pm_runtime_resume_and_get(&pdev->dev);
-	if (ret < 0)
-		return ret;
+	if (ret < 0) {
+		/* Note, if this error path is taken, we're leaking some
+		 * resources.
+		 */
+		dev_err(&pdev->dev, "Failed to resume device (%pe)\n",
+			ERR_PTR(ret));
+		return;
+	}
 
 	for (i = 0; i < cpsw->data.slaves; i++)
 		if (cpsw->slaves[i].ndev)
@@ -1740,7 +1746,6 @@  static int cpsw_remove(struct platform_device *pdev)
 	cpsw_remove_dt(pdev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-	return 0;
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -1795,7 +1800,7 @@  static struct platform_driver cpsw_driver = {
 		.of_match_table = cpsw_of_mtable,
 	},
 	.probe = cpsw_probe,
-	.remove = cpsw_remove,
+	.remove_new = cpsw_remove,
 };
 
 module_platform_driver(cpsw_driver);