usb: gadget: remove net2280_set_fifo_mode()

This function has no user in my tree. It looks like it belongs to
net2280 but it somehow morphed into the dummy_hcd. So I remove it
before it spreads into more drivers.
After some digging I figured out that the only user was removed in

|commit 9079e91b
|Author: David Brownell <david-b@pacbell.net>
|Date:   Wed May 7 16:00:36 2008 -0700
|
|    USB: serial gadget: cleanup/reorg
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/dummy_hcd.c

@@ -976,16 +976,6 @@ static int dummy_udc_stop(struct usb_gadget_driver *driver)
 
 #undef is_enabled
 
-/* just declare this in any driver that really need it */
-extern int net2280_set_fifo_mode (struct usb_gadget *gadget, int mode);
-
-int net2280_set_fifo_mode (struct usb_gadget *gadget, int mode)
-{
-	return -ENOSYS;
-}
-EXPORT_SYMBOL (net2280_set_fifo_mode);
-
-
 /* The gadget structure is stored inside the hcd structure and will be
  * released along with it. */
 static void

drivers/usb/gadget/net2280.c

@@ -1744,62 +1744,6 @@ static void set_fifo_mode (struct net2280 *dev, int mode)
 	list_add_tail (&dev->ep [6].ep.ep_list, &dev->gadget.ep_list);
 }
 
-/* just declare this in any driver that really need it */
-extern int net2280_set_fifo_mode (struct usb_gadget *gadget, int mode);
-
-/**
- * net2280_set_fifo_mode - change allocation of fifo buffers
- * @gadget: access to the net2280 device that will be updated
- * @mode: 0 for default, four 1kB buffers (ep-a through ep-d);
- *	1 for two 2kB buffers (ep-a and ep-b only);
- *	2 for one 2kB buffer (ep-a) and two 1kB ones (ep-b, ep-c).
- *
- * returns zero on success, else negative errno.  when this succeeds,
- * the contents of gadget->ep_list may have changed.
- *
- * you may only call this function when endpoints a-d are all disabled.
- * use it whenever extra hardware buffering can help performance, such
- * as before enabling "high bandwidth" interrupt endpoints that use
- * maxpacket bigger than 512 (when double buffering would otherwise
- * be unavailable).
- */
-int net2280_set_fifo_mode (struct usb_gadget *gadget, int mode)
-{
-	int			i;
-	struct net2280		*dev;
-	int			status = 0;
-	unsigned long		flags;
-
-	if (!gadget)
-		return -ENODEV;
-	dev = container_of (gadget, struct net2280, gadget);
-
-	spin_lock_irqsave (&dev->lock, flags);
-
-	for (i = 1; i <= 4; i++)
-		if (dev->ep [i].desc) {
-			status = -EINVAL;
-			break;
-		}
-	if (mode < 0 || mode > 2)
-		status = -EINVAL;
-	if (status == 0)
-		set_fifo_mode (dev, mode);
-	spin_unlock_irqrestore (&dev->lock, flags);
-
-	if (status == 0) {
-		if (mode == 1)
-			DEBUG (dev, "fifo:  ep-a 2K, ep-b 2K\n");
-		else if (mode == 2)
-			DEBUG (dev, "fifo:  ep-a 2K, ep-b 1K, ep-c 1K\n");
-		/* else all are 1K */
-	}
-	return status;
-}
-EXPORT_SYMBOL (net2280_set_fifo_mode);
-
-/*-------------------------------------------------------------------------*/
-
 /* keeping it simple:
  * - one bus driver, initted first;
  * - one function driver, initted second