If IRQ occurs between calling  dsps_setup_optional_vbus_irq()
and  dsps_create_musb_pdev(), then null pointer dereference occurs
since glue->musb wasn't initialized yet.
The patch puts initializing of neccesery data before registration
of the interrupt handler.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Nadezda Lutovinova <lutovinova@ispras.ru>
Link: https://lore.kernel.org/r/20210819163323.17714-1-lutovinova@ispras.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
        if (!glue->usbss_base)
                return -ENXIO;
 
-       if (usb_get_dr_mode(&pdev->dev) == USB_DR_MODE_PERIPHERAL) {
-               ret = dsps_setup_optional_vbus_irq(pdev, glue);
-               if (ret)
-                       goto err_iounmap;
-       }
-
        platform_set_drvdata(pdev, glue);
        pm_runtime_enable(&pdev->dev);
        ret = dsps_create_musb_pdev(glue, pdev);
        if (ret)
                goto err;
 
+       if (usb_get_dr_mode(&pdev->dev) == USB_DR_MODE_PERIPHERAL) {
+               ret = dsps_setup_optional_vbus_irq(pdev, glue);
+               if (ret)
+                       goto err;
+       }
+
        return 0;
 
 err:
        pm_runtime_disable(&pdev->dev);
-err_iounmap:
        iounmap(glue->usbss_base);
        return ret;
 }