[PATCH 6.1.y 1/2] usb: gadget: at91_udc: Convert to platform remove callback returning void

[Sasha Levin <sashal@kernel.org>]

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ Upstream commit cbd1b152519a581bfe14fb6b14ea6e57cca426c1 ]

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().

In the error path emit an error message replacing the (less useful)
message by the core. Apart from the improved error message there is no
change in behaviour.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231120215830.71071-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: c27d13ce4bab ("usb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/udc/at91_udc.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/gadget/udc/at91_udc.c b/drivers/usb/gadget/udc/at91_udc.c
index a9a7b3fc60ec9..96d0aabe3c85e 100644
--- a/drivers/usb/gadget/udc/at91_udc.c
+++ b/drivers/usb/gadget/udc/at91_udc.c
@@ -1927,7 +1927,7 @@ static int at91udc_probe(struct platform_device *pdev)
 	return retval;
 }
 
-static int at91udc_remove(struct platform_device *pdev)
+static void at91udc_remove(struct platform_device *pdev)
 {
 	struct at91_udc *udc = platform_get_drvdata(pdev);
 	unsigned long	flags;
@@ -1935,8 +1935,11 @@ static int at91udc_remove(struct platform_device *pdev)
 	DBG("remove\n");
 
 	usb_del_gadget_udc(&udc->gadget);
-	if (udc->driver)
-		return -EBUSY;
+	if (udc->driver) {
+		dev_err(&pdev->dev,
+			"Driver still in use but removing anyhow\n");
+		return;
+	}
 
 	spin_lock_irqsave(&udc->lock, flags);
 	pullup(udc, 0);
@@ -1946,8 +1949,6 @@ static int at91udc_remove(struct platform_device *pdev)
 	remove_debug_file(udc);
 	clk_unprepare(udc->fclk);
 	clk_unprepare(udc->iclk);
-
-	return 0;
 }
 
 #ifdef CONFIG_PM
@@ -2003,7 +2004,7 @@ static int at91udc_resume(struct platform_device *pdev)
 #endif
 
 static struct platform_driver at91_udc_driver = {
-	.remove		= at91udc_remove,
+	.remove_new	= at91udc_remove,
 	.shutdown	= at91udc_shutdown,
 	.suspend	= at91udc_suspend,
 	.resume		= at91udc_resume,
-- 
2.53.0