Input: pxrc - do not store USB device in private struct

The USB device is only needed during setup, so put it back after
initialization and do not store it in our private struct.

Also, the USB device is a parent of USB interface so our driver
model rules ensure that USB device should not disappear while
interface device is still there; there is no need to take reference
to the USB device.

Reported-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/joystick/pxrc.c

@@ -27,7 +27,6 @@ MODULE_DEVICE_TABLE(usb, pxrc_table);
 
 struct pxrc {
 	struct input_dev	*input;
-	struct usb_device	*udev;
 	struct usb_interface	*intf;
 	struct urb		*urb;
 	struct mutex		pm_mutex;
@@ -122,6 +121,7 @@ static void pxrc_close(struct input_dev *input)
 
 static int pxrc_usb_init(struct pxrc *pxrc)
 {
+	struct usb_device *udev = interface_to_usbdev(pxrc->intf);
 	struct usb_endpoint_descriptor *epirq;
 	unsigned int pipe;
 	int retval;
@@ -145,7 +145,7 @@ static int pxrc_usb_init(struct pxrc *pxrc)
 	}
 
 	usb_set_intfdata(pxrc->intf, pxrc);
-	usb_make_path(pxrc->udev, pxrc->phys, sizeof(pxrc->phys));
+	usb_make_path(udev, pxrc->phys, sizeof(pxrc->phys));
 	strlcat(pxrc->phys, "/input0", sizeof(pxrc->phys));
 
 	pxrc->urb = usb_alloc_urb(0, GFP_KERNEL);
@@ -154,9 +154,9 @@ static int pxrc_usb_init(struct pxrc *pxrc)
 		goto error;
 	}
 
-	pipe = usb_rcvintpipe(pxrc->udev, pxrc->epaddr),
-	usb_fill_int_urb(pxrc->urb, pxrc->udev, pipe, pxrc->data, pxrc->bsize,
-						pxrc_usb_irq, pxrc, 1);
+	pipe = usb_rcvintpipe(udev, pxrc->epaddr),
+	usb_fill_int_urb(pxrc->urb, udev, pipe, pxrc->data, pxrc->bsize,
+			 pxrc_usb_irq, pxrc, 1);
 
 error:
 	return retval;
@@ -174,7 +174,7 @@ static int pxrc_input_init(struct pxrc *pxrc)
 
 	pxrc->input->name = "PXRC Flight Controller Adapter";
 	pxrc->input->phys = pxrc->phys;
-	usb_to_input_id(pxrc->udev, &pxrc->input->id);
+	usb_to_input_id(interface_to_usbdev(pxrc->intf), &pxrc->input->id);
 
 	pxrc->input->open = pxrc_open;
 	pxrc->input->close = pxrc_close;
@@ -204,7 +204,6 @@ static int pxrc_probe(struct usb_interface *intf,
 		return -ENOMEM;
 
 	mutex_init(&pxrc->pm_mutex);
-	pxrc->udev = usb_get_dev(interface_to_usbdev(intf));
 	pxrc->intf = intf;
 
 	retval = pxrc_usb_init(pxrc);