usb: gadget: gr_udc: Convert to platform remove callback returning void

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/20231120215830.71071-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/gr_udc.c b/drivers/usb/gadget/udc/gr_udc.c
index c6dfa7cccc11da1025302dab5ded2043a5dc806b..fb901be5dac1b7a4fe7fc4203c5757bccb8275a6 100644 (file)
--- a/drivers/usb/gadget/udc/gr_udc.c
+++ b/drivers/usb/gadget/udc/gr_udc.c
@@ -2089,15 +2089,18 @@ static void gr_ep_remove(struct gr_udc *dev, int num, int is_in)
                                  ep->tailbuf, ep->tailbuf_paddr);
 }
 
-static int gr_remove(struct platform_device *pdev)
+static void gr_remove(struct platform_device *pdev)
 {
        struct gr_udc *dev = platform_get_drvdata(pdev);
        int i;
 
        if (dev->added)
                usb_del_gadget_udc(&dev->gadget); /* Shuts everything down */
-       if (dev->driver)
-               return -EBUSY;
+       if (dev->driver) {
+               dev_err(&pdev->dev,
+                       "Driver still in use but removing anyhow\n");
+               return;
+       }
 
        gr_dfs_delete(dev);
        dma_pool_destroy(dev->desc_pool);
@@ -2110,8 +2113,6 @@ static int gr_remove(struct platform_device *pdev)
                gr_ep_remove(dev, i, 0);
        for (i = 0; i < dev->nepi; i++)
                gr_ep_remove(dev, i, 1);
-
-       return 0;
 }
 static int gr_request_irq(struct gr_udc *dev, int irq)
 {
@@ -2248,7 +2249,7 @@ static struct platform_driver gr_driver = {
                .of_match_table = gr_match,
        },
        .probe = gr_probe,
-       .remove = gr_remove,
+       .remove_new = gr_remove,
 };
 module_platform_driver(gr_driver);