[PATCH] usb: gadget: tegra-xudc: Request IRQ after initialization

[Runyu Xiao]

tegra_xudc_probe() requests the IRQ before initializing the state used by
tegra_xudc_irq(). The handler may run immediately and access the event ring
or lock before they are ready.

Request the IRQ after initializing all handler-visible state and before
usb_add_gadget_udc() publishes the UDC. That call may bind a gadget driver.
If UDC registration fails, release the managed IRQ before freeing state.

Fixes: 49db427232fe ("usb: gadget: Add UDC driver for tegra XUSB device mode controller")
Cc: stable@xxxxxxxxxxxxxxx
Assisted-by: LLM
Signed-off-by: Runyu Xiao <runyu.xiao@xxxxxxxxxx>
---
 drivers/usb/gadget/udc/tegra-xudc.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/gadget/udc/tegra-xudc.c b/drivers/usb/gadget/udc/tegra-xudc.c
index e9d33be028664..5b133b9d65631 100644
--- a/drivers/usb/gadget/udc/tegra-xudc.c
+++ b/drivers/usb/gadget/udc/tegra-xudc.c
@@ -3801,14 +3801,6 @@ static int tegra_xudc_probe(struct platform_device *pdev)
 	if (xudc->irq < 0)
 		return xudc->irq;
 
-	err = devm_request_irq(&pdev->dev, xudc->irq, tegra_xudc_irq, 0,
-			       dev_name(&pdev->dev), xudc);
-	if (err < 0) {
-		dev_err(xudc->dev, "failed to claim IRQ#%u: %d\n", xudc->irq,
-			err);
-		return err;
-	}
-
 	xudc->clks = devm_kcalloc(&pdev->dev, xudc->soc->num_clks, sizeof(*xudc->clks),
 				  GFP_KERNEL);
 	if (!xudc->clks)
@@ -3886,9 +3878,18 @@ static int tegra_xudc_probe(struct platform_device *pdev)
 	xudc->gadget.name = "tegra-xudc";
 	xudc->gadget.max_speed = USB_SPEED_SUPER;
 
+	err = devm_request_irq(&pdev->dev, xudc->irq, tegra_xudc_irq, 0,
+			       dev_name(&pdev->dev), xudc);
+	if (err < 0) {
+		dev_err(xudc->dev, "failed to claim IRQ#%u: %d\n", xudc->irq,
+			err);
+		goto free_eps;
+	}
+
 	err = usb_add_gadget_udc(&pdev->dev, &xudc->gadget);
 	if (err) {
 		dev_err(&pdev->dev, "failed to add USB gadget: %d\n", err);
+		devm_free_irq(&pdev->dev, xudc->irq, xudc);
 		goto free_eps;
 	}
 
-- 
2.34.1