[PATCH 0/7] extcon: Convert to platform remove callback returning void

[PATCH 0/7] extcon: Convert to platform remove callback returning void

[Uwe Kleine-König]

Hello,

this series converts all drivers below drivers/extcon to struct
platform_driver::remove_new(). See commit 5c5a7680e67b ("platform:
Provide a remove callback that returns no value") for an extended
explanation and the eventual goal.

All conversations are trivial, because their .remove() callbacks
returned zero unconditionally.

There are no interdependencies between these patches, so they could be
picked up individually. But I'd hope that they get picked up all
together by the extcon maintainer team.

Best regards
Uwe

Uwe Kleine-König (7):
  extcon: adc-jack: Convert to platform remove callback returning void
  extcon: intel-cht-wc: Convert to platform remove callback returning void
  extcon: intel-mrfld: Convert to platform remove callback returning void
  extcon: max3355: Convert to platform remove callback returning void
  extcon: max77843: Convert to platform remove callback returning void
  extcon: usb-gpio: Convert to platform remove callback returning void
  extcon: usbc-cros-ec: Convert to platform remove callback returning void

 drivers/extcon/extcon-adc-jack.c     | 6 ++----
 drivers/extcon/extcon-intel-cht-wc.c | 6 ++----
 drivers/extcon/extcon-intel-mrfld.c  | 6 ++----
 drivers/extcon/extcon-max3355.c      | 6 ++----
 drivers/extcon/extcon-max77843.c     | 6 ++----
 drivers/extcon/extcon-usb-gpio.c     | 6 ++----
 drivers/extcon/extcon-usbc-cros-ec.c | 6 ++----
 7 files changed, 14 insertions(+), 28 deletions(-)

base-commit: 33e1d31873f87d119e5120b88cd350efa68ef276
-- 
2.43.0

[PATCH 7/7] extcon: usbc-cros-ec: Convert to platform remove callback returning void

[Uwe Kleine-König]

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/extcon/extcon-usbc-cros-ec.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/extcon/extcon-usbc-cros-ec.c b/drivers/extcon/extcon-usbc-cros-ec.c
index fde1db62be0d..805a47230689 100644
--- a/drivers/extcon/extcon-usbc-cros-ec.c
+++ b/drivers/extcon/extcon-usbc-cros-ec.c
@@ -480,14 +480,12 @@ static int extcon_cros_ec_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int extcon_cros_ec_remove(struct platform_device *pdev)
+static void extcon_cros_ec_remove(struct platform_device *pdev)
 {
 	struct cros_ec_extcon_info *info = platform_get_drvdata(pdev);
 
 	blocking_notifier_chain_unregister(&info->ec->event_notifier,
 					   &info->notifier);
-
-	return 0;
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -531,7 +529,7 @@ static struct platform_driver extcon_cros_ec_driver = {
 		.of_match_table = of_match_ptr(extcon_cros_ec_of_match),
 		.pm = DEV_PM_OPS,
 	},
-	.remove  = extcon_cros_ec_remove,
+	.remove_new = extcon_cros_ec_remove,
 	.probe   = extcon_cros_ec_probe,
 };
 
-- 
2.43.0

Re: [PATCH 7/7] extcon: usbc-cros-ec: Convert to platform remove callback returning void

[Tzung-Bi Shih]

On Sun, Feb 25, 2024 at 04:54:56PM +0100, 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().
> 
> 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>

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>

RE: [PATCH 0/7] extcon: Convert to platform remove callback returning void

[Chanwoo Choi]

> -----Original Message-----
> From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> Sent: Monday, February 26, 2024 12:55 AM
> To: MyungJoo Ham <myungjoo.ham@samsung.com>; Chanwoo Choi
> <cw00.choi@samsung.com>
> Cc: linux-kernel@vger.kernel.org; Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org>; Benson Leung <bleung@chromium.org>; Guenter
> Roeck <groeck@chromium.org>; chrome-platform@lists.linux.dev
> Subject: [PATCH 0/7] extcon: Convert to platform remove callback returning
> void
> 
> Hello,
> 
> this series converts all drivers below drivers/extcon to struct
> platform_driver::remove_new(). See commit 5c5a7680e67b ("platform:
> Provide a remove callback that returns no value") for an extended explanation
> and the eventual goal.
> 
> All conversations are trivial, because their .remove() callbacks returned
> zero unconditionally.
> 
> There are no interdependencies between these patches, so they could be picked
> up individually. But I'd hope that they get picked up all together by the
> extcon maintainer team.
> 
> Best regards
> Uwe
> 
> Uwe Kleine-König (7):
>   extcon: adc-jack: Convert to platform remove callback returning void
>   extcon: intel-cht-wc: Convert to platform remove callback returning void
>   extcon: intel-mrfld: Convert to platform remove callback returning void
>   extcon: max3355: Convert to platform remove callback returning void
>   extcon: max77843: Convert to platform remove callback returning void
>   extcon: usb-gpio: Convert to platform remove callback returning void
>   extcon: usbc-cros-ec: Convert to platform remove callback returning void
> 
>  drivers/extcon/extcon-adc-jack.c     | 6 ++----
>  drivers/extcon/extcon-intel-cht-wc.c | 6 ++----  drivers/extcon/extcon-
> intel-mrfld.c  | 6 ++----
>  drivers/extcon/extcon-max3355.c      | 6 ++----
>  drivers/extcon/extcon-max77843.c     | 6 ++----
>  drivers/extcon/extcon-usb-gpio.c     | 6 ++----
>  drivers/extcon/extcon-usbc-cros-ec.c | 6 ++----
>  7 files changed, 14 insertions(+), 28 deletions(-)
> 

Applied them. Thanks.

Best Regards,
Chanwoo Choi