18 files changed, 354 insertions, 325 deletions

diff --git a/drivers/usb/gadget/at91_udc.c b/drivers/usb/gadget/at91_udc.c
index eaa79c8..93ead19 100644
--- a/drivers/usb/gadget/at91_udc.c
+++ b/drivers/usb/gadget/at91_udc.c
@@ -76,11 +76,12 @@
 static const char driver_name [] = "at91_udc";
 static const char ep0name[] = "ep0";
 
+#define VBUS_POLL_TIMEOUT	msecs_to_jiffies(1000)
 
-#define at91_udp_read(dev, reg) \
-	__raw_readl((dev)->udp_baseaddr + (reg))
-#define at91_udp_write(dev, reg, val) \
-	__raw_writel((val), (dev)->udp_baseaddr + (reg))
+#define at91_udp_read(udc, reg) \
+	__raw_readl((udc)->udp_baseaddr + (reg))
+#define at91_udp_write(udc, reg, val) \
+	__raw_writel((val), (udc)->udp_baseaddr + (reg))
 
 /*-------------------------------------------------------------------------*/
 
@@ -102,8 +103,9 @@ static void proc_ep_show(struct seq_file *s, struct at91_ep *ep)
 	u32			csr;
 	struct at91_request	*req;
 	unsigned long	flags;
+	struct at91_udc	*udc = ep->udc;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	csr = __raw_readl(ep->creg);
 
@@ -147,7 +149,7 @@ static void proc_ep_show(struct seq_file *s, struct at91_ep *ep)
 				&req->req, length,
 				req->req.length, req->req.buf);
 	}
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 }
 
 static void proc_irq_show(struct seq_file *s, const char *label, u32 mask)
@@ -272,7 +274,9 @@ static void done(struct at91_ep *ep, struct at91_request *req, int status)
 		VDBG("%s done %p, status %d\n", ep->ep.name, req, status);
 
 	ep->stopped = 1;
+	spin_unlock(&udc->lock);
 	req->req.complete(&ep->ep, &req->req);
+	spin_lock(&udc->lock);
 	ep->stopped = stopped;
 
 	/* ep0 is always ready; other endpoints need a non-empty queue */
@@ -472,7 +476,7 @@ static int at91_ep_enable(struct usb_ep *_ep,
 				const struct usb_endpoint_descriptor *desc)
 {
 	struct at91_ep	*ep = container_of(_ep, struct at91_ep, ep);
-	struct at91_udc	*dev = ep->udc;
+	struct at91_udc	*udc = ep->udc;
 	u16		maxpacket;
 	u32		tmp;
 	unsigned long	flags;
@@ -487,7 +491,7 @@ static int at91_ep_enable(struct usb_ep *_ep,
 		return -EINVAL;
 	}
 
-	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
 		DBG("bogus device state\n");
 		return -ESHUTDOWN;
 	}
@@ -521,7 +525,7 @@ bogus_max:
 	}
 
 ok:
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	/* initialize endpoint to match this descriptor */
 	ep->is_in = usb_endpoint_dir_in(desc);
@@ -540,10 +544,10 @@ ok:
 	 * reset/init endpoint fifo.  NOTE:  leaves fifo_bank alone,
 	 * since endpoint resets don't reset hw pingpong state.
 	 */
-	at91_udp_write(dev, AT91_UDP_RST_EP, ep->int_mask);
-	at91_udp_write(dev, AT91_UDP_RST_EP, 0);
+	at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);
+	at91_udp_write(udc, AT91_UDP_RST_EP, 0);
 
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -556,7 +560,7 @@ static int at91_ep_disable (struct usb_ep * _ep)
 	if (ep == &ep->udc->ep[0])
 		return -EINVAL;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	nuke(ep, -ESHUTDOWN);
 
@@ -571,7 +575,7 @@ static int at91_ep_disable (struct usb_ep * _ep)
 		__raw_writel(0, ep->creg);
 	}
 
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -607,7 +611,7 @@ static int at91_ep_queue(struct usb_ep *_ep,
 {
 	struct at91_request	*req;
 	struct at91_ep		*ep;
-	struct at91_udc		*dev;
+	struct at91_udc		*udc;
 	int			status;
 	unsigned long		flags;
 
@@ -625,9 +629,9 @@ static int at91_ep_queue(struct usb_ep *_ep,
 		return -EINVAL;
 	}
 
-	dev = ep->udc;
+	udc = ep->udc;
 
-	if (!dev || !dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {
+	if (!udc || !udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
 		DBG("invalid device\n");
 		return -EINVAL;
 	}
@@ -635,7 +639,7 @@ static int at91_ep_queue(struct usb_ep *_ep,
 	_req->status = -EINPROGRESS;
 	_req->actual = 0;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	/* try to kickstart any empty and idle queue */
 	if (list_empty(&ep->queue) && !ep->stopped) {
@@ -653,7 +657,7 @@ static int at91_ep_queue(struct usb_ep *_ep,
 		if (is_ep0) {
 			u32	tmp;
 
-			if (!dev->req_pending) {
+			if (!udc->req_pending) {
 				status = -EINVAL;
 				goto done;
 			}
@@ -662,11 +666,11 @@ static int at91_ep_queue(struct usb_ep *_ep,
 			 * defer changing CONFG until after the gadget driver
 			 * reconfigures the endpoints.
 			 */
-			if (dev->wait_for_config_ack) {
-				tmp = at91_udp_read(dev, AT91_UDP_GLB_STAT);
+			if (udc->wait_for_config_ack) {
+				tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);
 				tmp ^= AT91_UDP_CONFG;
 				VDBG("toggle config\n");
-				at91_udp_write(dev, AT91_UDP_GLB_STAT, tmp);
+				at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);
 			}
 			if (req->req.length == 0) {
 ep0_in_status:
@@ -676,7 +680,7 @@ ep0_in_status:
 				tmp &= ~SET_FX;
 				tmp |= CLR_FX | AT91_UDP_TXPKTRDY;
 				__raw_writel(tmp, ep->creg);
-				dev->req_pending = 0;
+				udc->req_pending = 0;
 				goto done;
 			}
 		}
@@ -695,31 +699,40 @@ ep0_in_status:
 
 	if (req && !status) {
 		list_add_tail (&req->queue, &ep->queue);
-		at91_udp_write(dev, AT91_UDP_IER, ep->int_mask);
+		at91_udp_write(udc, AT91_UDP_IER, ep->int_mask);
 	}
 done:
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return (status < 0) ? status : 0;
 }
 
 static int at91_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 {
-	struct at91_ep	*ep;
+	struct at91_ep		*ep;
 	struct at91_request	*req;
+	unsigned long		flags;
+	struct at91_udc		*udc;
 
 	ep = container_of(_ep, struct at91_ep, ep);
 	if (!_ep || ep->ep.name == ep0name)
 		return -EINVAL;
 
+	udc = ep->udc;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
 	/* make sure it's actually queued on this endpoint */
 	list_for_each_entry (req, &ep->queue, queue) {
 		if (&req->req == _req)
 			break;
 	}
-	if (&req->req != _req)
+	if (&req->req != _req) {
+		spin_unlock_irqrestore(&udc->lock, flags);
 		return -EINVAL;
+	}
 
 	done(ep, req, -ECONNRESET);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -736,7 +749,7 @@ static int at91_ep_set_halt(struct usb_ep *_ep, int value)
 		return -EINVAL;
 
 	creg = ep->creg;
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	csr = __raw_readl(creg);
 
@@ -761,7 +774,7 @@ static int at91_ep_set_halt(struct usb_ep *_ep, int value)
 		__raw_writel(csr, creg);
 	}
 
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return status;
 }
 
@@ -795,7 +808,7 @@ static int at91_wakeup(struct usb_gadget *gadget)
 	unsigned long	flags;
 
 	DBG("%s\n", __func__ );
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 
 	if (!udc->clocked || !udc->suspended)
 		goto done;
@@ -809,7 +822,7 @@ static int at91_wakeup(struct usb_gadget *gadget)
 	at91_udp_write(udc, AT91_UDP_GLB_STAT, glbstate);
 
 done:
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return status;
 }
 
@@ -851,8 +864,11 @@ static void stop_activity(struct at91_udc *udc)
 		ep->stopped = 1;
 		nuke(ep, -ESHUTDOWN);
 	}
-	if (driver)
+	if (driver) {
+		spin_unlock(&udc->lock);
 		driver->disconnect(&udc->gadget);
+		spin_lock(&udc->lock);
+	}
 
 	udc_reinit(udc);
 }
@@ -935,13 +951,13 @@ static int at91_vbus_session(struct usb_gadget *gadget, int is_active)
 	unsigned long	flags;
 
 	// VDBG("vbus %s\n", is_active ? "on" : "off");
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 	udc->vbus = (is_active != 0);
 	if (udc->driver)
 		pullup(udc, is_active);
 	else
 		pullup(udc, 0);
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -950,10 +966,10 @@ static int at91_pullup(struct usb_gadget *gadget, int is_on)
 	struct at91_udc	*udc = to_udc(gadget);
 	unsigned long	flags;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 	udc->enabled = is_on = !!is_on;
 	pullup(udc, is_on);
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -962,9 +978,9 @@ static int at91_set_selfpowered(struct usb_gadget *gadget, int is_on)
 	struct at91_udc	*udc = to_udc(gadget);
 	unsigned long	flags;
 
-	local_irq_save(flags);
+	spin_lock_irqsave(&udc->lock, flags);
 	udc->selfpowered = (is_on != 0);
-	local_irq_restore(flags);
+	spin_unlock_irqrestore(&udc->lock, flags);
 	return 0;
 }
 
@@ -1226,8 +1242,11 @@ static void handle_setup(struct at91_udc *udc, struct at91_ep *ep, u32 csr)
 #undef w_length
 
 	/* pass request up to the gadget driver */
-	if (udc->driver)
+	if (udc->driver) {
+		spin_unlock(&udc->lock);
 		status = udc->driver->setup(&udc->gadget, &pkt.r);
+		spin_lock(&udc->lock);
+	}
 	else
 		status = -ENODEV;
 	if (status < 0) {
@@ -1378,6 +1397,9 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc)
 	struct at91_udc		*udc = _udc;
 	u32			rescans = 5;
 	int			disable_clock = 0;
+	unsigned long		flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
 
 	if (!udc->clocked) {
 		clk_on(udc);
@@ -1433,8 +1455,11 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc)
 			 * and then into standby to avoid drawing more than
 			 * 500uA power (2500uA for some high-power configs).
 			 */
-			if (udc->driver && udc->driver->suspend)
+			if (udc->driver && udc->driver->suspend) {
+				spin_unlock(&udc->lock);
 				udc->driver->suspend(&udc->gadget);
+				spin_lock(&udc->lock);
+			}
 
 		/* host initiated resume */
 		} else if (status & AT91_UDP_RXRSM) {
@@ -1451,8 +1476,11 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc)
 			 * would normally want to switch out of slow clock
 			 * mode into normal mode.
 			 */
-			if (udc->driver && udc->driver->resume)
+			if (udc->driver && udc->driver->resume) {
+				spin_unlock(&udc->lock);
 				udc->driver->resume(&udc->gadget);
+				spin_lock(&udc->lock);
+			}
 
 		/* endpoint IRQs are cleared by handling them */
 		} else {
@@ -1474,6 +1502,8 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc)
 	if (disable_clock)
 		clk_off(udc);
 
+	spin_unlock_irqrestore(&udc->lock, flags);
+
 	return IRQ_HANDLED;
 }
 
@@ -1556,24 +1586,53 @@ static struct at91_udc controller = {
 	/* ep6 and ep7 are also reserved (custom silicon might use them) */
 };
 
+static void at91_vbus_update(struct at91_udc *udc, unsigned value)
+{
+	value ^= udc->board.vbus_active_low;
+	if (value != udc->vbus)
+		at91_vbus_session(&udc->gadget, value);
+}
+
 static irqreturn_t at91_vbus_irq(int irq, void *_udc)
 {
 	struct at91_udc	*udc = _udc;
-	unsigned	value;
 
 	/* vbus needs at least brief debouncing */
 	udelay(10);
-	value = gpio_get_value(udc->board.vbus_pin);
-	if (value != udc->vbus)
-		at91_vbus_session(&udc->gadget, value);
+	at91_vbus_update(udc, gpio_get_value(udc->board.vbus_pin));
 
 	return IRQ_HANDLED;
 }
 
+static void at91_vbus_timer_work(struct work_struct *work)
+{
+	struct at91_udc *udc = container_of(work, struct at91_udc,
+					    vbus_timer_work);
+
+	at91_vbus_update(udc, gpio_get_value_cansleep(udc->board.vbus_pin));
+
+	if (!timer_pending(&udc->vbus_timer))
+		mod_timer(&udc->vbus_timer, jiffies + VBUS_POLL_TIMEOUT);
+}
+
+static void at91_vbus_timer(unsigned long data)
+{
+	struct at91_udc *udc = (struct at91_udc *)data;
+
+	/*
+	 * If we are polling vbus it is likely that the gpio is on an
+	 * bus such as i2c or spi which may sleep, so schedule some work
+	 * to read the vbus gpio
+	 */
+	if (!work_pending(&udc->vbus_timer_work))
+		schedule_work(&udc->vbus_timer_work);
+}
+
 int usb_gadget_register_driver (struct usb_gadget_driver *driver)
 {
 	struct at91_udc	*udc = &controller;
 	int		retval;
+	unsigned long	flags;
 
 	if (!driver
 			|| driver->speed < USB_SPEED_FULL
@@ -1605,9 +1664,9 @@ int usb_gadget_register_driver (struct usb_gadget_driver *driver)
 		return retval;
 	}
 
-	local_irq_disable();
+	spin_lock_irqsave(&udc->lock, flags);
 	pullup(udc, 1);
-	local_irq_enable();
+	spin_unlock_irqrestore(&udc->lock, flags);
 
 	DBG("bound to %s\n", driver->driver.name);
 	return 0;
@@ -1617,15 +1676,16 @@ EXPORT_SYMBOL (usb_gadget_register_driver);
 int usb_gadget_unregister_driver (struct usb_gadget_driver *driver)
 {
 	struct at91_udc *udc = &controller;
+	unsigned long	flags;
 
 	if (!driver || driver != udc->driver || !driver->unbind)
 		return -EINVAL;
 
-	local_irq_disable();
+	spin_lock_irqsave(&udc->lock, flags);
 	udc->enabled = 0;
 	at91_udp_write(udc, AT91_UDP_IDR, ~0);
 	pullup(udc, 0);
-	local_irq_enable();
+	spin_unlock_irqrestore(&udc->lock, flags);
 
 	driver->unbind(&udc->gadget);
 	udc->gadget.dev.driver = NULL;
@@ -1641,8 +1701,13 @@ EXPORT_SYMBOL (usb_gadget_unregister_driver);
 
 static void at91udc_shutdown(struct platform_device *dev)
 {
+	struct at91_udc *udc = platform_get_drvdata(dev);
+	unsigned long	flags;
+
 	/* force disconnect on reboot */
+	spin_lock_irqsave(&udc->lock, flags);
 	pullup(platform_get_drvdata(dev), 0);
+	spin_unlock_irqrestore(&udc->lock, flags);
 }
 
 static int __init at91udc_probe(struct platform_device *pdev)
@@ -1683,6 +1748,7 @@ static int __init at91udc_probe(struct platform_device *pdev)
 	udc->board = *(struct at91_udc_data *) dev->platform_data;
 	udc->pdev = pdev;
 	udc->enabled = 0;
+	spin_lock_init(&udc->lock);
 
 	/* rm9200 needs manual D+ pullup; off by default */
 	if (cpu_is_at91rm9200()) {
@@ -1763,13 +1829,23 @@ static int __init at91udc_probe(struct platform_device *pdev)
 		 * Get the initial state of VBUS - we cannot expect
 		 * a pending interrupt.
 		 */
-		udc->vbus = gpio_get_value(udc->board.vbus_pin);
-		if (request_irq(udc->board.vbus_pin, at91_vbus_irq,
-				IRQF_DISABLED, driver_name, udc)) {
-			DBG("request vbus irq %d failed\n",
-					udc->board.vbus_pin);
-			retval = -EBUSY;
-			goto fail3;
+		udc->vbus = gpio_get_value_cansleep(udc->board.vbus_pin) ^
+			udc->board.vbus_active_low;
+
+		if (udc->board.vbus_polled) {
+			INIT_WORK(&udc->vbus_timer_work, at91_vbus_timer_work);
+			setup_timer(&udc->vbus_timer, at91_vbus_timer,
+				    (unsigned long)udc);
+			mod_timer(&udc->vbus_timer,
+				  jiffies + VBUS_POLL_TIMEOUT);
+		} else {
+			if (request_irq(udc->board.vbus_pin, at91_vbus_irq,
+					IRQF_DISABLED, driver_name, udc)) {
+				DBG("request vbus irq %d failed\n",
+				    udc->board.vbus_pin);
+				retval = -EBUSY;
+				goto fail3;
+			}
 		}
 	} else {
 		DBG("no VBUS detection, assuming always-on\n");
@@ -1804,13 +1880,16 @@ static int __exit at91udc_remove(struct platform_device *pdev)
 {
 	struct at91_udc *udc = platform_get_drvdata(pdev);
 	struct resource *res;
+	unsigned long	flags;
 
 	DBG("remove\n");
 
 	if (udc->driver)
 		return -EBUSY;
 
+	spin_lock_irqsave(&udc->lock, flags);
 	pullup(udc, 0);
+	spin_unlock_irqrestore(&udc->lock, flags);
 
 	device_init_wakeup(&pdev->dev, 0);
 	remove_debug_file(udc);
@@ -1840,6 +1919,7 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg)
 {
 	struct at91_udc *udc = platform_get_drvdata(pdev);
 	int		wake = udc->driver && device_may_wakeup(&pdev->dev);
+	unsigned long	flags;
 
 	/* Unless we can act normally to the host (letting it wake us up
 	 * whenever it has work for us) force disconnect.  Wakeup requires
@@ -1849,13 +1929,15 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg)
 	if ((!udc->suspended && udc->addr)
 			|| !wake
 			|| at91_suspend_entering_slow_clock()) {
+		spin_lock_irqsave(&udc->lock, flags);
 		pullup(udc, 0);
 		wake = 0;
+		spin_unlock_irqrestore(&udc->lock, flags);
 	} else
 		enable_irq_wake(udc->udp_irq);
 
 	udc->active_suspend = wake;
-	if (udc->board.vbus_pin > 0 && wake)
+	if (udc->board.vbus_pin > 0 && !udc->board.vbus_polled && wake)
 		enable_irq_wake(udc->board.vbus_pin);
 	return 0;
 }
@@ -1863,15 +1945,20 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg)
 static int at91udc_resume(struct platform_device *pdev)
 {
 	struct at91_udc *udc = platform_get_drvdata(pdev);
+	unsigned long	flags;
 
-	if (udc->board.vbus_pin > 0 && udc->active_suspend)
+	if (udc->board.vbus_pin > 0 && !udc->board.vbus_polled &&
+	    udc->active_suspend)
 		disable_irq_wake(udc->board.vbus_pin);
 
 	/* maybe reconnect to host; if so, clocks on */
 	if (udc->active_suspend)
 		disable_irq_wake(udc->udp_irq);
-	else
+	else {
+		spin_lock_irqsave(&udc->lock, flags);
 		pullup(udc, 1);
+		spin_unlock_irqrestore(&udc->lock, flags);
+	}
 	return 0;
 }
 #else
diff --git a/drivers/usb/gadget/at91_udc.h b/drivers/usb/gadget/at91_udc.h
index c65d622..108ca54 100644
--- a/drivers/usb/gadget/at91_udc.h
+++ b/drivers/usb/gadget/at91_udc.h
@@ -144,6 +144,9 @@ struct at91_udc {
 	struct proc_dir_entry		*pde;
 	void __iomem			*udp_baseaddr;
 	int				udp_irq;
+	spinlock_t			lock;
+	struct timer_list		vbus_timer;
+	struct work_struct		vbus_timer_work;
 };
 
 static inline struct at91_udc *to_udc(struct usb_gadget *g)
diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c
index 38226e9..95dd466 100644
--- a/drivers/usb/gadget/f_eem.c
+++ b/drivers/usb/gadget/f_eem.c
@@ -469,8 +469,7 @@ static int eem_unwrap(struct gether *port,
 				crc = get_unaligned_le32(skb->data + len
 							- ETH_FCS_LEN);
 				crc2 = ~crc32_le(~0,
-						skb->data,
-						skb->len - ETH_FCS_LEN);
+						skb->data, len - ETH_FCS_LEN);
 			} else {
 				crc = get_unaligned_be32(skb->data + len
 							- ETH_FCS_LEN);
diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c
index d69eccf..2aaa0f7 100644
--- a/drivers/usb/gadget/f_fs.c
+++ b/drivers/usb/gadget/f_fs.c
@@ -136,7 +136,7 @@ struct ffs_data {
 	 * handling setup requests immidiatelly user space may be so
 	 * slow that another setup will be sent to the gadget but this
 	 * time not to us but another function and then there could be
-	 * a race.  Is taht the case? Or maybe we can use cdev->req
+	 * a race.  Is that the case? Or maybe we can use cdev->req
 	 * after all, maybe we just need some spinlock for that? */
 	struct usb_request		*ep0req;		/* P: mutex */
 	struct completion		ep0req_completion;	/* P: mutex */
diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index 7d05a0b..4ce899c 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -321,8 +321,8 @@ struct fsg_dev;
 /* Data shared by all the FSG instances. */
 struct fsg_common {
 	struct usb_gadget	*gadget;
-	struct fsg_dev		*fsg;
-	struct fsg_dev		*prev_fsg;
+	struct fsg_dev		*fsg, *new_fsg;
+	wait_queue_head_t	fsg_wait;
 
 	/* filesem protects: backing files in use */
 	struct rw_semaphore	filesem;
@@ -351,7 +351,6 @@ struct fsg_common {
 	enum fsg_state		state;		/* For exception handling */
 	unsigned int		exception_req_tag;
 
-	u8			config, new_config;
 	enum data_direction	data_dir;
 	u32			data_size;
 	u32			data_size_from_cmnd;
@@ -595,7 +594,7 @@ static int fsg_setup(struct usb_function *f,
 	u16			w_value = le16_to_cpu(ctrl->wValue);
 	u16			w_length = le16_to_cpu(ctrl->wLength);
 
-	if (!fsg->common->config)
+	if (!fsg_is_set(fsg->common))
 		return -EOPNOTSUPP;
 
 	switch (ctrl->bRequest) {
@@ -2303,24 +2302,20 @@ static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
 	return -ENOMEM;
 }
 
-/*
- * Reset interface setting and re-init endpoint state (toggle etc).
- * Call with altsetting < 0 to disable the interface.  The only other
- * available altsetting is 0, which enables the interface.
- */
-static int do_set_interface(struct fsg_common *common, int altsetting)
+/* Reset interface setting and re-init endpoint state (toggle etc). */
+static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
 {
-	int	rc = 0;
-	int	i;
-	const struct usb_endpoint_descriptor	*d;
+	const struct usb_endpoint_descriptor *d;
+	struct fsg_dev *fsg;
+	int i, rc = 0;
 
 	if (common->running)
 		DBG(common, "reset interface\n");
 
 reset:
 	/* Deallocate the requests */
-	if (common->prev_fsg) {
-		struct fsg_dev *fsg = common->prev_fsg;
+	if (common->fsg) {
+		fsg = common->fsg;
 
 		for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
 			struct fsg_buffhd *bh = &common->buffhds[i];
@@ -2345,88 +2340,53 @@ reset:
 			fsg->bulk_out_enabled = 0;
 		}
 
-		common->prev_fsg = 0;
+		common->fsg = NULL;
+		wake_up(&common->fsg_wait);
 	}
 
 	common->running = 0;
-	if (altsetting < 0 || rc != 0)
+	if (!new_fsg || rc)
 		return rc;
 
-	DBG(common, "set interface %d\n", altsetting);
+	common->fsg = new_fsg;
+	fsg = common->fsg;
 
-	if (fsg_is_set(common)) {
-		struct fsg_dev *fsg = common->fsg;
-		common->prev_fsg = common->fsg;
+	/* Enable the endpoints */
+	d = fsg_ep_desc(common->gadget,
+			&fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
+	rc = enable_endpoint(common, fsg->bulk_in, d);
+	if (rc)
+		goto reset;
+	fsg->bulk_in_enabled = 1;
+
+	d = fsg_ep_desc(common->gadget,
+			&fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
+	rc = enable_endpoint(common, fsg->bulk_out, d);
+	if (rc)
+		goto reset;
+	fsg->bulk_out_enabled = 1;
+	common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
+	clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
 
-		/* Enable the endpoints */
-		d = fsg_ep_desc(common->gadget,
-				&fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
-		rc = enable_endpoint(common, fsg->bulk_in, d);
+	/* Allocate the requests */
+	for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
+		struct fsg_buffhd	*bh = &common->buffhds[i];
+
+		rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
 		if (rc)
 			goto reset;
-		fsg->bulk_in_enabled = 1;
-
-		d = fsg_ep_desc(common->gadget,
-				&fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
-		rc = enable_endpoint(common, fsg->bulk_out, d);
+		rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
 		if (rc)
 			goto reset;
-		fsg->bulk_out_enabled = 1;
-		common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
-		clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-
-		/* Allocate the requests */
-		for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-			struct fsg_buffhd	*bh = &common->buffhds[i];
-
-			rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
-			if (rc)
-				goto reset;
-			rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
-			if (rc)
-				goto reset;
-			bh->inreq->buf = bh->outreq->buf = bh->buf;
-			bh->inreq->context = bh->outreq->context = bh;
-			bh->inreq->complete = bulk_in_complete;
-			bh->outreq->complete = bulk_out_complete;
-		}
-
-		common->running = 1;
-		for (i = 0; i < common->nluns; ++i)
-			common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
-		return rc;
-	} else {
-		return -EIO;
-	}
-}
-
-
-/*
- * Change our operational configuration.  This code must agree with the code
- * that returns config descriptors, and with interface altsetting code.
- *
- * It's also responsible for power management interactions.  Some
- * configurations might not work with our current power sources.
- * For now we just assume the gadget is always self-powered.
- */
-static int do_set_config(struct fsg_common *common, u8 new_config)
-{
-	int	rc = 0;
-
-	/* Disable the single interface */
-	if (common->config != 0) {
-		DBG(common, "reset config\n");
-		common->config = 0;
-		rc = do_set_interface(common, -1);
+		bh->inreq->buf = bh->outreq->buf = bh->buf;
+		bh->inreq->context = bh->outreq->context = bh;
+		bh->inreq->complete = bulk_in_complete;
+		bh->outreq->complete = bulk_out_complete;
 	}
 
-	/* Enable the interface */
-	if (new_config != 0) {
-		common->config = new_config;
-		rc = do_set_interface(common, 0);
-		if (rc != 0)
-			common->config = 0;	/* Reset on errors */
-	}
+	common->running = 1;
+	for (i = 0; i < common->nluns; ++i)
+		common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
 	return rc;
 }
 
@@ -2437,9 +2397,7 @@ static int do_set_config(struct fsg_common *common, u8 new_config)
 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
 	struct fsg_dev *fsg = fsg_from_func(f);
-	fsg->common->prev_fsg = fsg->common->fsg;
-	fsg->common->fsg = fsg;
-	fsg->common->new_config = 1;
+	fsg->common->new_fsg = fsg;
 	raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
 	return 0;
 }
@@ -2447,9 +2405,7 @@ static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 static void fsg_disable(struct usb_function *f)
 {
 	struct fsg_dev *fsg = fsg_from_func(f);
-	fsg->common->prev_fsg = fsg->common->fsg;
-	fsg->common->fsg = fsg;
-	fsg->common->new_config = 0;
+	fsg->common->new_fsg = NULL;
 	raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
 }
 
@@ -2459,19 +2415,17 @@ static void fsg_disable(struct usb_function *f)
 static void handle_exception(struct fsg_common *common)
 {
 	siginfo_t		info;
-	int			sig;
 	int			i;
 	struct fsg_buffhd	*bh;
 	enum fsg_state		old_state;
-	u8			new_config;
 	struct fsg_lun		*curlun;
 	unsigned int		exception_req_tag;
-	int			rc;
 
 	/* Clear the existing signals.  Anything but SIGUSR1 is converted
 	 * into a high-priority EXIT exception. */
 	for (;;) {
-		sig = dequeue_signal_lock(current, &current->blocked, &info);
+		int sig =
+			dequeue_signal_lock(current, &current->blocked, &info);
 		if (!sig)
 			break;
 		if (sig != SIGUSR1) {
@@ -2482,7 +2436,7 @@ static void handle_exception(struct fsg_common *common)
 	}
 
 	/* Cancel all the pending transfers */
-	if (fsg_is_set(common)) {
+	if (likely(common->fsg)) {
 		for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
 			bh = &common->buffhds[i];
 			if (bh->inreq_busy)
@@ -2523,7 +2477,6 @@ static void handle_exception(struct fsg_common *common)
 	common->next_buffhd_to_fill = &common->buffhds[0];
 	common->next_buffhd_to_drain = &common->buffhds[0];
 	exception_req_tag = common->exception_req_tag;
-	new_config = common->new_config;
 	old_state = common->state;
 
 	if (old_state == FSG_STATE_ABORT_BULK_OUT)
@@ -2573,12 +2526,12 @@ static void handle_exception(struct fsg_common *common)
 		break;
 
 	case FSG_STATE_CONFIG_CHANGE:
-		rc = do_set_config(common, new_config);
+		do_set_interface(common, common->new_fsg);
 		break;
 
 	case FSG_STATE_EXIT:
 	case FSG_STATE_TERMINATED:
-		do_set_config(common, 0);		/* Free resources */
+		do_set_interface(common, NULL);		/* Free resources */
 		spin_lock_irq(&common->lock);
 		common->state = FSG_STATE_TERMINATED;	/* Stop the thread */
 		spin_unlock_irq(&common->lock);
@@ -2863,6 +2816,7 @@ buffhds_first_it:
 		goto error_release;
 	}
 	init_completion(&common->thread_notifier);
+	init_waitqueue_head(&common->fsg_wait);
 #undef OR
 
 
@@ -2957,9 +2911,17 @@ static void fsg_common_release(struct kref *ref)
 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct fsg_dev		*fsg = fsg_from_func(f);
+	struct fsg_common	*common = fsg->common;
 
 	DBG(fsg, "unbind\n");
-	fsg_common_put(fsg->common);
+	if (fsg->common->fsg == fsg) {
+		fsg->common->new_fsg = NULL;
+		raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
+		/* FIXME: make interruptible or killable somehow? */
+		wait_event(common->fsg_wait, common->fsg != fsg);
+	}
+
+	fsg_common_put(common);
 	usb_free_descriptors(fsg->function.descriptors);
 	usb_free_descriptors(fsg->function.hs_descriptors);
 	kfree(fsg);
@@ -2970,7 +2932,6 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct fsg_dev		*fsg = fsg_from_func(f);
 	struct usb_gadget	*gadget = c->cdev->gadget;
-	int			rc;
 	int			i;
 	struct usb_ep		*ep;
 
@@ -2996,6 +2957,11 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
 	ep->driver_data = fsg->common;	/* claim the endpoint */
 	fsg->bulk_out = ep;
 
+	/* Copy descriptors */
+	f->descriptors = usb_copy_descriptors(fsg_fs_function);
+	if (unlikely(!f->descriptors))
+		return -ENOMEM;
+
 	if (gadget_is_dualspeed(gadget)) {
 		/* Assume endpoint addresses are the same for both speeds */
 		fsg_hs_bulk_in_desc.bEndpointAddress =
@@ -3003,16 +2969,17 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
 		fsg_hs_bulk_out_desc.bEndpointAddress =
 			fsg_fs_bulk_out_desc.bEndpointAddress;
 		f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
-		if (unlikely(!f->hs_descriptors))
+		if (unlikely(!f->hs_descriptors)) {
+			usb_free_descriptors(f->descriptors);
 			return -ENOMEM;
+		}
 	}
 
 	return 0;
 
 autoconf_fail:
 	ERROR(fsg, "unable to autoconfigure all endpoints\n");
-	rc = -ENOTSUPP;
-	return rc;
+	return -ENOTSUPP;
 }
 
 
@@ -3036,11 +3003,6 @@ static int fsg_add(struct usb_composite_dev *cdev,
 
 	fsg->function.name        = FSG_DRIVER_DESC;
 	fsg->function.strings     = fsg_strings_array;
-	fsg->function.descriptors = usb_copy_descriptors(fsg_fs_function);
-	if (unlikely(!fsg->function.descriptors)) {
-		rc = -ENOMEM;
-		goto error_free_fsg;
-	}
 	fsg->function.bind        = fsg_bind;
 	fsg->function.unbind      = fsg_unbind;
 	fsg->function.setup       = fsg_setup;
@@ -3056,19 +3018,9 @@ static int fsg_add(struct usb_composite_dev *cdev,
 
 	rc = usb_add_function(c, &fsg->function);
 	if (unlikely(rc))
-		goto error_free_all;
-
-	fsg_common_get(fsg->common);
-	return 0;
-
-error_free_all:
-	usb_free_descriptors(fsg->function.descriptors);
-	/* fsg_bind() might have copied those; or maybe not? who cares
-	 * -- free it just in case. */
-	usb_free_descriptors(fsg->function.hs_descriptors);
-error_free_fsg:
-	kfree(fsg);
-
+		kfree(fsg);
+	else
+		fsg_common_get(fsg->common);
 	return rc;
 }
 
diff --git a/drivers/usb/gadget/f_uvc.c b/drivers/usb/gadget/f_uvc.c
index fc2611f..dbe6db0 100644
--- a/drivers/usb/gadget/f_uvc.c
+++ b/drivers/usb/gadget/f_uvc.c
@@ -28,7 +28,7 @@
 
 #include "uvc.h"
 
-unsigned int uvc_trace_param;
+unsigned int uvc_gadget_trace_param;
 
 /* --------------------------------------------------------------------------
  * Function descriptors
@@ -656,6 +656,6 @@ error:
 	return ret;
 }
 
-module_param_named(trace, uvc_trace_param, uint, S_IRUGO|S_IWUSR);
+module_param_named(trace, uvc_gadget_trace_param, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(trace, "Trace level bitmask");
 
diff --git a/drivers/usb/gadget/fsl_mxc_udc.c b/drivers/usb/gadget/fsl_mxc_udc.c
index d0b8bde..eafa6d2 100644
--- a/drivers/usb/gadget/fsl_mxc_udc.c
+++ b/drivers/usb/gadget/fsl_mxc_udc.c
@@ -30,7 +30,7 @@ int fsl_udc_clk_init(struct platform_device *pdev)
 
 	pdata = pdev->dev.platform_data;
 
-	if (!cpu_is_mx35()) {
+	if (!cpu_is_mx35() && !cpu_is_mx25()) {
 		mxc_ahb_clk = clk_get(&pdev->dev, "usb_ahb");
 		if (IS_ERR(mxc_ahb_clk))
 			return PTR_ERR(mxc_ahb_clk);
diff --git a/drivers/usb/gadget/g_ffs.c b/drivers/usb/gadget/g_ffs.c
index 4b0e4a0..d1af253 100644
--- a/drivers/usb/gadget/g_ffs.c
+++ b/drivers/usb/gadget/g_ffs.c
@@ -392,6 +392,17 @@ static int __gfs_do_config(struct usb_configuration *c,
 	if (unlikely(ret < 0))
 		return ret;
 
+	/* After previous do_configs there may be some invalid
+	 * pointers in c->interface array.  This happens every time
+	 * a user space function with fewer interfaces than a user
+	 * space function that was run before the new one is run.  The
+	 * compasit's set_config() assumes that if there is no more
+	 * then MAX_CONFIG_INTERFACES interfaces in a configuration
+	 * then there is a NULL pointer after the last interface in
+	 * c->interface array.  We need to make sure this is true. */
+	if (c->next_interface_id < ARRAY_SIZE(c->interface))
+		c->interface[c->next_interface_id] = NULL;
+
 	return 0;
 }
 
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index 43abf55..4c3ac5c 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -82,7 +82,7 @@ static struct class *usb_gadget_class;
 struct printer_dev {
 	spinlock_t		lock;		/* lock this structure */
 	/* lock buffer lists during read/write calls */
-	spinlock_t		lock_printer_io;
+	struct mutex		lock_printer_io;
 	struct usb_gadget	*gadget;
 	struct usb_request	*req;		/* for control responses */
 	u8			config;
@@ -567,7 +567,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 
 	DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
 
-	spin_lock(&dev->lock_printer_io);
+	mutex_lock(&dev->lock_printer_io);
 	spin_lock_irqsave(&dev->lock, flags);
 
 	/* We will use this flag later to check if a printer reset happened
@@ -601,7 +601,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 		 * call or not.
 		 */
 		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
 		}
 
@@ -648,7 +648,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 		if (dev->reset_printer) {
 			list_add(&current_rx_req->list, &dev->rx_reqs);
 			spin_unlock_irqrestore(&dev->lock, flags);
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
 		}
 
@@ -673,7 +673,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 	dev->current_rx_buf = current_rx_buf;
 
 	spin_unlock_irqrestore(&dev->lock, flags);
-	spin_unlock(&dev->lock_printer_io);
+	mutex_unlock(&dev->lock_printer_io);
 
 	DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
 
@@ -697,7 +697,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 	if (len == 0)
 		return -EINVAL;
 
-	spin_lock(&dev->lock_printer_io);
+	mutex_lock(&dev->lock_printer_io);
 	spin_lock_irqsave(&dev->lock, flags);
 
 	/* Check if a printer reset happens while we have interrupts on */
@@ -713,7 +713,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 		 * a NON-Blocking call or not.
 		 */
 		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
 		}
 
@@ -752,7 +752,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 
 		if (copy_from_user(req->buf, buf, size)) {
 			list_add(&req->list, &dev->tx_reqs);
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return bytes_copied;
 		}
 
@@ -766,14 +766,14 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 		if (dev->reset_printer) {
 			list_add(&req->list, &dev->tx_reqs);
 			spin_unlock_irqrestore(&dev->lock, flags);
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
 		}
 
 		if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
 			list_add(&req->list, &dev->tx_reqs);
 			spin_unlock_irqrestore(&dev->lock, flags);
-			spin_unlock(&dev->lock_printer_io);
+			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
 		}
 
@@ -782,7 +782,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 	}
 
 	spin_unlock_irqrestore(&dev->lock, flags);
-	spin_unlock(&dev->lock_printer_io);
+	mutex_unlock(&dev->lock_printer_io);
 
 	DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
 
@@ -820,11 +820,11 @@ printer_poll(struct file *fd, poll_table *wait)
 	unsigned long		flags;
 	int			status = 0;
 
-	spin_lock(&dev->lock_printer_io);
+	mutex_lock(&dev->lock_printer_io);
 	spin_lock_irqsave(&dev->lock, flags);
 	setup_rx_reqs(dev);
 	spin_unlock_irqrestore(&dev->lock, flags);
-	spin_unlock(&dev->lock_printer_io);
+	mutex_unlock(&dev->lock_printer_io);
 
 	poll_wait(fd, &dev->rx_wait, wait);
 	poll_wait(fd, &dev->tx_wait, wait);
@@ -1461,7 +1461,7 @@ autoconf_fail:
 	}
 
 	spin_lock_init(&dev->lock);
-	spin_lock_init(&dev->lock_printer_io);
+	mutex_init(&dev->lock_printer_io);
 	INIT_LIST_HEAD(&dev->tx_reqs);
 	INIT_LIST_HEAD(&dev->tx_reqs_active);
 	INIT_LIST_HEAD(&dev->rx_reqs);
@@ -1594,7 +1594,7 @@ cleanup(void)
 {
 	int status;
 
-	spin_lock(&usb_printer_gadget.lock_printer_io);
+	mutex_lock(&usb_printer_gadget.lock_printer_io);
 	class_destroy(usb_gadget_class);
 	unregister_chrdev_region(g_printer_devno, 2);
 
@@ -1602,6 +1602,6 @@ cleanup(void)
 	if (status)
 		ERROR(dev, "usb_gadget_unregister_driver %x\n", status);
 
-	spin_unlock(&usb_printer_gadget.lock_printer_io);
+	mutex_unlock(&usb_printer_gadget.lock_printer_io);
 }
 module_exit(cleanup);
diff --git a/drivers/usb/gadget/pxa27x_udc.c b/drivers/usb/gadget/pxa27x_udc.c
index 85b0d89..9807624 100644
--- a/drivers/usb/gadget/pxa27x_udc.c
+++ b/drivers/usb/gadget/pxa27x_udc.c
@@ -2561,7 +2561,7 @@ static void pxa_udc_shutdown(struct platform_device *_dev)
 		udc_disable(udc);
 }
 
-#ifdef CONFIG_CPU_PXA27x
+#ifdef CONFIG_PXA27x
 extern void pxa27x_clear_otgph(void);
 #else
 #define pxa27x_clear_otgph()   do {} while (0)
diff --git a/drivers/usb/gadget/s3c2410_udc.c b/drivers/usb/gadget/s3c2410_udc.c
index d5f4c1d..ea2b3c7 100644
--- a/drivers/usb/gadget/s3c2410_udc.c
+++ b/drivers/usb/gadget/s3c2410_udc.c
@@ -735,6 +735,10 @@ static void s3c2410_udc_handle_ep0_idle(struct s3c2410_udc *dev,
 	else
 		dev->ep0state = EP0_OUT_DATA_PHASE;
 
+	if (!dev->driver)
+		return;
+
+	/* deliver the request to the gadget driver */
 	ret = dev->driver->setup(&dev->gadget, crq);
 	if (ret < 0) {
 		if (dev->req_config) {
@@ -1700,9 +1704,13 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
 	if (!driver || driver != udc->driver || !driver->unbind)
 		return -EINVAL;
 
-	dprintk(DEBUG_NORMAL,"usb_gadget_register_driver() '%s'\n",
+	dprintk(DEBUG_NORMAL, "usb_gadget_unregister_driver() '%s'\n",
 		driver->driver.name);
 
+	/* report disconnect */
+	if (driver->disconnect)
+		driver->disconnect(&udc->gadget);
+
 	driver->unbind(&udc->gadget);
 
 	device_del(&udc->gadget.dev);
diff --git a/drivers/usb/gadget/u_serial.c b/drivers/usb/gadget/u_serial.c
index 16bdf77..3e8dcb5 100644
--- a/drivers/usb/gadget/u_serial.c
+++ b/drivers/usb/gadget/u_serial.c
@@ -536,17 +536,11 @@ recycle:
 		list_move(&req->list, &port->read_pool);
 	}
 
-	/* Push from tty to ldisc; this is immediate with low_latency, and
-	 * may trigger callbacks to this driver ... so drop the spinlock.
+	/* Push from tty to ldisc; without low_latency set this is handled by
+	 * a workqueue, so we won't get callbacks and can hold port_lock
 	 */
 	if (tty && do_push) {
-		spin_unlock_irq(&port->port_lock);
 		tty_flip_buffer_push(tty);
-		wake_up_interruptible(&tty->read_wait);
-		spin_lock_irq(&port->port_lock);
-
-		/* tty may have been closed */
-		tty = port->port_tty;
 	}
 
 
@@ -784,11 +778,6 @@ static int gs_open(struct tty_struct *tty, struct file *file)
 	port->open_count = 1;
 	port->openclose = false;
 
-	/* low_latency means ldiscs work in tasklet context, without
-	 * needing a workqueue schedule ... easier to keep up.
-	 */
-	tty->low_latency = 1;
-
 	/* if connected, start the I/O stream */
 	if (port->port_usb) {
 		struct gserial	*gser = port->port_usb;
@@ -1195,6 +1184,7 @@ void gserial_cleanup(void)
 	n_ports = 0;
 
 	tty_unregister_driver(gs_tty_driver);
+	put_tty_driver(gs_tty_driver);
 	gs_tty_driver = NULL;
 
 	pr_debug("%s: cleaned up ttyGS* support\n", __func__);
diff --git a/drivers/usb/gadget/uvc.h b/drivers/usb/gadget/uvc.h
index 0a705e6..e92454c 100644
--- a/drivers/usb/gadget/uvc.h
+++ b/drivers/usb/gadget/uvc.h
@@ -107,11 +107,11 @@ struct uvc_streaming_control {
 #define UVC_WARN_MINMAX				0
 #define UVC_WARN_PROBE_DEF			1
 
-extern unsigned int uvc_trace_param;
+extern unsigned int uvc_gadget_trace_param;
 
 #define uvc_trace(flag, msg...) \
 	do { \
-		if (uvc_trace_param & flag) \
+		if (uvc_gadget_trace_param & flag) \
 			printk(KERN_DEBUG "uvcvideo: " msg); \
 	} while (0)
 
@@ -220,16 +220,10 @@ struct uvc_file_handle
 #define to_uvc_file_handle(handle) \
 	container_of(handle, struct uvc_file_handle, vfh)
 
-extern struct v4l2_file_operations uvc_v4l2_fops;
-
 /* ------------------------------------------------------------------------
  * Functions
  */
 
-extern int uvc_video_enable(struct uvc_video *video, int enable);
-extern int uvc_video_init(struct uvc_video *video);
-extern int uvc_video_pump(struct uvc_video *video);
-
 extern void uvc_endpoint_stream(struct uvc_device *dev);
 
 extern void uvc_function_connect(struct uvc_device *uvc);
diff --git a/drivers/usb/gadget/uvc_queue.c b/drivers/usb/gadget/uvc_queue.c
index 4389199..f7395ac 100644
--- a/drivers/usb/gadget/uvc_queue.c
+++ b/drivers/usb/gadget/uvc_queue.c
@@ -78,7 +78,8 @@
  *
  */
 
-void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
+static void
+uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
 	mutex_init(&queue->mutex);
 	spin_lock_init(&queue->irqlock);
@@ -88,6 +89,28 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 }
 
 /*
+ * Free the video buffers.
+ *
+ * This function must be called with the queue lock held.
+ */
+static int uvc_free_buffers(struct uvc_video_queue *queue)
+{
+	unsigned int i;
+
+	for (i = 0; i < queue->count; ++i) {
+		if (queue->buffer[i].vma_use_count != 0)
+			return -EBUSY;
+	}
+
+	if (queue->count) {
+		vfree(queue->mem);
+		queue->count = 0;
+	}
+
+	return 0;
+}
+
+/*
  * Allocate the video buffers.
  *
  * Pages are reserved to make sure they will not be swapped, as they will be
@@ -95,8 +118,9 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
  *
  * Buffers will be individually mapped, so they must all be page aligned.
  */
-int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
-		unsigned int buflength)
+static int
+uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
+		  unsigned int buflength)
 {
 	unsigned int bufsize = PAGE_ALIGN(buflength);
 	unsigned int i;
@@ -150,28 +174,6 @@ done:
 	return ret;
 }
 
-/*
- * Free the video buffers.
- *
- * This function must be called with the queue lock held.
- */
-int uvc_free_buffers(struct uvc_video_queue *queue)
-{
-	unsigned int i;
-
-	for (i = 0; i < queue->count; ++i) {
-		if (queue->buffer[i].vma_use_count != 0)
-			return -EBUSY;
-	}
-
-	if (queue->count) {
-		vfree(queue->mem);
-		queue->count = 0;
-	}
-
-	return 0;
-}
-
 static void __uvc_query_buffer(struct uvc_buffer *buf,
 		struct v4l2_buffer *v4l2_buf)
 {
@@ -195,8 +197,8 @@ static void __uvc_query_buffer(struct uvc_buffer *buf,
 	}
 }
 
-int uvc_query_buffer(struct uvc_video_queue *queue,
-		struct v4l2_buffer *v4l2_buf)
+static int
+uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf)
 {
 	int ret = 0;
 
@@ -217,8 +219,8 @@ done:
  * Queue a video buffer. Attempting to queue a buffer that has already been
  * queued will return -EINVAL.
  */
-int uvc_queue_buffer(struct uvc_video_queue *queue,
-	struct v4l2_buffer *v4l2_buf)
+static int
+uvc_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf)
 {
 	struct uvc_buffer *buf;
 	unsigned long flags;
@@ -298,8 +300,9 @@ static int uvc_queue_waiton(struct uvc_buffer *buf, int nonblocking)
  * Dequeue a video buffer. If nonblocking is false, block until a buffer is
  * available.
  */
-int uvc_dequeue_buffer(struct uvc_video_queue *queue,
-		struct v4l2_buffer *v4l2_buf, int nonblocking)
+static int
+uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf,
+		   int nonblocking)
 {
 	struct uvc_buffer *buf;
 	int ret = 0;
@@ -359,8 +362,9 @@ done:
  * This function implements video queue polling and is intended to be used by
  * the device poll handler.
  */
-unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
-		poll_table *wait)
+static unsigned int
+uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
+	       poll_table *wait)
 {
 	struct uvc_buffer *buf;
 	unsigned int mask = 0;
@@ -407,7 +411,8 @@ static struct vm_operations_struct uvc_vm_ops = {
  * This function implements video buffer memory mapping and is intended to be
  * used by the device mmap handler.
  */
-int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
+static int
+uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
 {
 	struct uvc_buffer *uninitialized_var(buffer);
 	struct page *page;
@@ -458,6 +463,42 @@ done:
 }
 
 /*
+ * Cancel the video buffers queue.
+ *
+ * Cancelling the queue marks all buffers on the irq queue as erroneous,
+ * wakes them up and removes them from the queue.
+ *
+ * If the disconnect parameter is set, further calls to uvc_queue_buffer will
+ * fail with -ENODEV.
+ *
+ * This function acquires the irq spinlock and can be called from interrupt
+ * context.
+ */
+static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
+{
+	struct uvc_buffer *buf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->irqlock, flags);
+	while (!list_empty(&queue->irqqueue)) {
+		buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
+				       queue);
+		list_del(&buf->queue);
+		buf->state = UVC_BUF_STATE_ERROR;
+		wake_up(&buf->wait);
+	}
+	/* This must be protected by the irqlock spinlock to avoid race
+	 * conditions between uvc_queue_buffer and the disconnection event that
+	 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
+	 * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
+	 * state outside the queue code.
+	 */
+	if (disconnect)
+		queue->flags |= UVC_QUEUE_DISCONNECTED;
+	spin_unlock_irqrestore(&queue->irqlock, flags);
+}
+
+/*
  * Enable or disable the video buffers queue.
  *
  * The queue must be enabled before starting video acquisition and must be
@@ -474,7 +515,7 @@ done:
  * This function can't be called from interrupt context. Use
  * uvc_queue_cancel() instead.
  */
-int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
+static int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
 {
 	unsigned int i;
 	int ret = 0;
@@ -503,44 +544,8 @@ done:
 	return ret;
 }
 
-/*
- * Cancel the video buffers queue.
- *
- * Cancelling the queue marks all buffers on the irq queue as erroneous,
- * wakes them up and removes them from the queue.
- *
- * If the disconnect parameter is set, further calls to uvc_queue_buffer will
- * fail with -ENODEV.
- *
- * This function acquires the irq spinlock and can be called from interrupt
- * context.
- */
-void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
-{
-	struct uvc_buffer *buf;
-	unsigned long flags;
-
-	spin_lock_irqsave(&queue->irqlock, flags);
-	while (!list_empty(&queue->irqqueue)) {
-		buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
-				       queue);
-		list_del(&buf->queue);
-		buf->state = UVC_BUF_STATE_ERROR;
-		wake_up(&buf->wait);
-	}
-	/* This must be protected by the irqlock spinlock to avoid race
-	 * conditions between uvc_queue_buffer and the disconnection event that
-	 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
-	 * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
-	 * state outside the queue code.
-	 */
-	if (disconnect)
-		queue->flags |= UVC_QUEUE_DISCONNECTED;
-	spin_unlock_irqrestore(&queue->irqlock, flags);
-}
-
-struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
-		struct uvc_buffer *buf)
+static struct uvc_buffer *
+uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf)
 {
 	struct uvc_buffer *nextbuf;
 	unsigned long flags;
@@ -568,7 +573,7 @@ struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
 	return nextbuf;
 }
 
-struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
+static struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
 {
 	struct uvc_buffer *buf = NULL;
 
diff --git a/drivers/usb/gadget/uvc_queue.h b/drivers/usb/gadget/uvc_queue.h
index 7f5a33f..1812a8e 100644
--- a/drivers/usb/gadget/uvc_queue.h
+++ b/drivers/usb/gadget/uvc_queue.h
@@ -58,30 +58,10 @@ struct uvc_video_queue {
 	struct list_head irqqueue;
 };
 
-extern void uvc_queue_init(struct uvc_video_queue *queue,
-		enum v4l2_buf_type type);
-extern int uvc_alloc_buffers(struct uvc_video_queue *queue,
-		unsigned int nbuffers, unsigned int buflength);
-extern int uvc_free_buffers(struct uvc_video_queue *queue);
-extern int uvc_query_buffer(struct uvc_video_queue *queue,
-		struct v4l2_buffer *v4l2_buf);
-extern int uvc_queue_buffer(struct uvc_video_queue *queue,
-		struct v4l2_buffer *v4l2_buf);
-extern int uvc_dequeue_buffer(struct uvc_video_queue *queue,
-		struct v4l2_buffer *v4l2_buf, int nonblocking);
-extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable);
-extern void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
-extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
-		struct uvc_buffer *buf);
-extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
-		struct file *file, poll_table *wait);
-extern int uvc_queue_mmap(struct uvc_video_queue *queue,
-		struct vm_area_struct *vma);
 static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
 {
 	return queue->flags & UVC_QUEUE_STREAMING;
 }
-extern struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue);
 
 #endif /* __KERNEL__ */
 
diff --git a/drivers/usb/gadget/uvc_v4l2.c b/drivers/usb/gadget/uvc_v4l2.c
index a7989f2..2dcffda 100644
--- a/drivers/usb/gadget/uvc_v4l2.c
+++ b/drivers/usb/gadget/uvc_v4l2.c
@@ -363,7 +363,7 @@ uvc_v4l2_poll(struct file *file, poll_table *wait)
 	return mask;
 }
 
-struct v4l2_file_operations uvc_v4l2_fops = {
+static struct v4l2_file_operations uvc_v4l2_fops = {
 	.owner		= THIS_MODULE,
 	.open		= uvc_v4l2_open,
 	.release	= uvc_v4l2_release,
diff --git a/drivers/usb/gadget/uvc_video.c b/drivers/usb/gadget/uvc_video.c
index de8cbc4..b08f354 100644
--- a/drivers/usb/gadget/uvc_video.c
+++ b/drivers/usb/gadget/uvc_video.c
@@ -271,7 +271,7 @@ error:
  * This function fills the available USB requests (listed in req_free) with
  * video data from the queued buffers.
  */
-int
+static int
 uvc_video_pump(struct uvc_video *video)
 {
 	struct usb_request *req;
@@ -328,7 +328,7 @@ uvc_video_pump(struct uvc_video *video)
 /*
  * Enable or disable the video stream.
  */
-int
+static int
 uvc_video_enable(struct uvc_video *video, int enable)
 {
 	unsigned int i;
@@ -367,7 +367,7 @@ uvc_video_enable(struct uvc_video *video, int enable)
 /*
  * Initialize the UVC video stream.
  */
-int
+static int
 uvc_video_init(struct uvc_video *video)
 {
 	INIT_LIST_HEAD(&video->req_free);
diff --git a/drivers/usb/gadget/webcam.c b/drivers/usb/gadget/webcam.c
index 417fd68..f5f3030 100644
--- a/drivers/usb/gadget/webcam.c
+++ b/drivers/usb/gadget/webcam.c
@@ -28,10 +28,10 @@
 #include "config.c"
 #include "epautoconf.c"
 
-#include "f_uvc.c"
 #include "uvc_queue.c"
-#include "uvc_v4l2.c"
 #include "uvc_video.c"
+#include "uvc_v4l2.c"
+#include "f_uvc.c"
 
 /* --------------------------------------------------------------------------
  * Device descriptor