[PATCH] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void

[PATCH] drm/bridge: imx8mp-hdmi-pvi: 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>
---
Hello,

note this driver is currently only available in next.

Best regards
Uwe

 drivers/gpu/drm/bridge/imx/imx8mp-hdmi-pvi.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-pvi.c b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-pvi.c
index f2a09c879e3d..073e64dc200c 100644
--- a/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-pvi.c
+++ b/drivers/gpu/drm/bridge/imx/imx8mp-hdmi-pvi.c
@@ -173,15 +173,13 @@ static int imx8mp_hdmi_pvi_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int imx8mp_hdmi_pvi_remove(struct platform_device *pdev)
+static void imx8mp_hdmi_pvi_remove(struct platform_device *pdev)
 {
 	struct imx8mp_hdmi_pvi *pvi = platform_get_drvdata(pdev);
 
 	drm_bridge_remove(&pvi->bridge);
 
 	pm_runtime_disable(&pdev->dev);
-
-	return 0;
 }
 
 static const struct of_device_id imx8mp_hdmi_pvi_match[] = {
@@ -195,7 +193,7 @@ MODULE_DEVICE_TABLE(of, imx8mp_hdmi_pvi_match);
 
 static struct platform_driver imx8mp_hdmi_pvi_driver = {
 	.probe	= imx8mp_hdmi_pvi_probe,
-	.remove	= imx8mp_hdmi_pvi_remove,
+	.remove_new = imx8mp_hdmi_pvi_remove,
 	.driver		= {
 		.name = "imx-hdmi-pvi",
 		.of_match_table	= imx8mp_hdmi_pvi_match,

base-commit: 67908bf6954b7635d33760ff6dfc189fc26ccc89
-- 
2.43.0

Re: [PATCH] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void

[Uwe Kleine-König]

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Hello,

On Mon, Mar 04, 2024 at 10:05:56AM +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>
> ---
> Hello,
> 
> note this driver is currently only available in next.

The driver made it into v6.9-rc1 as commit
059c53e877ca6e723e10490c27c1487a63e66efe. My change however didn't made
it into next yet. :-\

Who feels responsible here?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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Re: [PATCH] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void

[Robert Foss]

On Mon, 4 Mar 2024 10:05:56 +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().
> 
> [...]

Applied, thanks!

[1/1] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void
      https://cgit.freedesktop.org/drm/drm-misc/commit/?id=29b39672bc1d



Rob

Re: [PATCH] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void

[Uwe Kleine-König]

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Hello Rob,

On Wed, Apr 10, 2024 at 03:10:26PM +0200, Robert Foss wrote:
> On Mon, 4 Mar 2024 10:05:56 +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().
> > 
> > [...]
> 
> Applied, thanks!
> 
> [1/1] drm/bridge: imx8mp-hdmi-pvi: Convert to platform remove callback returning void
>       https://cgit.freedesktop.org/drm/drm-misc/commit/?id=29b39672bc1d

Great, do you feel like caring for its brother at

	https://lore.kernel.org/dri-devel/20240304091005.717012-2-u.kleine-koenig@pengutronix.de

, too?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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