usb: dwc2/gadget: delay enabling irq once hardware is configured properly

This patch fixes kernel panic/interrupt storm/etc issues if bootloader
left s3c-hsotg module in enabled state. Now interrupt handler is enabled
only after proper configuration of hardware registers.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Cc: stable <stable@vger.kernel.org> # 3.16
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/dwc2/gadget.c

@@ -3441,13 +3441,6 @@ static int s3c_hsotg_probe(struct platform_device *pdev)
 
 	hsotg->irq = ret;
 
-	ret = devm_request_irq(&pdev->dev, hsotg->irq, s3c_hsotg_irq, 0,
-				dev_name(dev), hsotg);
-	if (ret < 0) {
-		dev_err(dev, "cannot claim IRQ\n");
-		goto err_clk;
-	}
-
 	dev_info(dev, "regs %p, irq %d\n", hsotg->regs, hsotg->irq);
 
 	hsotg->gadget.max_speed = USB_SPEED_HIGH;
@@ -3495,6 +3488,17 @@ static int s3c_hsotg_probe(struct platform_device *pdev)
 	s3c_hsotg_init(hsotg);
 	s3c_hsotg_hw_cfg(hsotg);
 
+	ret = devm_request_irq(&pdev->dev, hsotg->irq, s3c_hsotg_irq, 0,
+				dev_name(dev), hsotg);
+	if (ret < 0) {
+		s3c_hsotg_phy_disable(hsotg);
+		clk_disable_unprepare(hsotg->clk);
+		regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
+				       hsotg->supplies);
+		dev_err(dev, "cannot claim IRQ\n");
+		goto err_clk;
+	}
+
 	/* hsotg->num_of_eps holds number of EPs other than ep0 */
 
 	if (hsotg->num_of_eps == 0) {