Merge tag 'usb-for-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

usb: patches for v4.1 merge window

As usual, a big pile of commits. This time a total
of 111 non-merge commits.

Other than the usual set of cleanups and non-critical
fixes, we have some interesting work for AM335x's MUSB
babble recovery. Now that takes a lot less time and we
don't have to Reset MUSB all the time.

The printer gadget has been converted to configfs interface
and the atmel udc has learned suspend/resume with wakeup.

Signed-off-by: Felipe Balbi <balbi@ti.com>

19 files changed, 2126 insertions, 1535 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index b454d05be583..bcf83c0a6e62 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -196,6 +196,9 @@ config USB_F_MIDI
 config USB_F_HID
 	tristate
 
+config USB_F_PRINTER
+	tristate
+
 choice
 	tristate "USB Gadget Drivers"
 	default USB_ETH
@@ -434,6 +437,20 @@ config USB_CONFIGFS_F_UVC
 	  device. It provides a userspace API to process UVC control requests
 	  and stream video data to the host.
 
+config USB_CONFIGFS_F_PRINTER
+	bool "Printer function"
+	select USB_F_PRINTER
+	depends on USB_CONFIGFS
+	help
+	  The Printer function channels data between the USB host and a
+	  userspace program driving the print engine. The user space
+	  program reads and writes the device file /dev/g_printer<X> to
+	  receive or send printer data. It can use ioctl calls to
+	  the device file to get or set printer status.
+
+	  For more information, see Documentation/usb/gadget_printer.txt
+	  which includes sample code for accessing the device file.
+
 source "drivers/usb/gadget/legacy/Kconfig"
 
 endchoice
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 13adfd1a3f54..4e3447bbd097 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1161,11 +1161,11 @@ static struct usb_gadget_string_container *copy_gadget_strings(
  * This function will create a deep copy of usb_gadget_strings and usb_string
  * and attach it to the cdev. The actual string (usb_string.s) will not be
  * copied but only a referenced will be made. The struct usb_gadget_strings
- * array may contain multiple languges and should be NULL terminated.
+ * array may contain multiple languages and should be NULL terminated.
  * The ->language pointer of each struct usb_gadget_strings has to contain the
  * same amount of entries.
  * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
- * usb_string entry of es-ES containts the translation of the first usb_string
+ * usb_string entry of es-ES contains the translation of the first usb_string
  * entry of en-US. Therefore both entries become the same id assign.
  */
 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
@@ -1472,6 +1472,13 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 	req->length = 0;
 	gadget->ep0->driver_data = cdev;
 
+	/*
+	 * Don't let non-standard requests match any of the cases below
+	 * by accident.
+	 */
+	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
+		goto unknown;
+
 	switch (ctrl->bRequest) {
 
 	/* we handle all standard USB descriptors */
@@ -1751,6 +1758,10 @@ unknown:
 		 * take such requests too, if that's ever needed:  to work
 		 * in config 0, etc.
 		 */
+		list_for_each_entry(f, &cdev->config->functions, list)
+			if (f->req_match && f->req_match(f, ctrl))
+				goto try_fun_setup;
+		f = NULL;
 		switch (ctrl->bRequestType & USB_RECIP_MASK) {
 		case USB_RECIP_INTERFACE:
 			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
@@ -1768,7 +1779,7 @@ unknown:
 				f = NULL;
 			break;
 		}
-
+try_fun_setup:
 		if (f && f->setup)
 			value = f->setup(f, ctrl);
 		else {
diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
index f71b1aaa0edf..bd7def576955 100644
--- a/drivers/usb/gadget/function/Makefile
+++ b/drivers/usb/gadget/function/Makefile
@@ -42,3 +42,5 @@ usb_f_midi-y			:= f_midi.o
 obj-$(CONFIG_USB_F_MIDI)	+= usb_f_midi.o
 usb_f_hid-y			:= f_hid.o
 obj-$(CONFIG_USB_F_HID)		+= usb_f_hid.o
+usb_f_printer-y			:= f_printer.o
+obj-$(CONFIG_USB_F_PRINTER)	+= usb_f_printer.o
diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index a2612fb79eff..13dfc9915b1d 100644
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -908,7 +908,6 @@ static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	/* disable/free request and end point */
 	usb_ep_disable(hidg->in_ep);
-	usb_ep_dequeue(hidg->in_ep, hidg->req);
 	kfree(hidg->req->buf);
 	usb_ep_free_request(hidg->in_ep, hidg->req);
 
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 49a2f19c2b87..3cc109f3c9c8 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -1085,7 +1085,7 @@ static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
 	if (!curlun) {		/* Unsupported LUNs are okay */
 		common->bad_lun_okay = 1;
 		memset(buf, 0, 36);
-		buf[0] = 0x7f;		/* Unsupported, no device-type */
+		buf[0] = TYPE_NO_LUN;	/* Unsupported, no device-type */
 		buf[4] = 31;		/* Additional length */
 		return 36;
 	}
diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c
new file mode 100644
index 000000000000..44173df27273
--- /dev/null
+++ b/drivers/usb/gadget/function/f_printer.c
@@ -0,0 +1,1471 @@
+/*
+ * f_printer.c - USB printer function driver
+ *
+ * Copied from drivers/usb/gadget/legacy/printer.c,
+ * which was:
+ *
+ * printer.c -- Printer gadget driver
+ *
+ * Copyright (C) 2003-2005 David Brownell
+ * Copyright (C) 2006 Craig W. Nadler
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/idr.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/moduleparam.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/cdev.h>
+
+#include <asm/byteorder.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/uaccess.h>
+#include <asm/unaligned.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/composite.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/g_printer.h>
+
+#include "u_printer.h"
+
+#define PNP_STRING_LEN		1024
+#define PRINTER_MINORS		4
+#define GET_DEVICE_ID		0
+#define GET_PORT_STATUS		1
+#define SOFT_RESET		2
+
+static int major, minors;
+static struct class *usb_gadget_class;
+static DEFINE_IDA(printer_ida);
+static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */
+
+/*-------------------------------------------------------------------------*/
+
+struct printer_dev {
+	spinlock_t		lock;		/* lock this structure */
+	/* lock buffer lists during read/write calls */
+	struct mutex		lock_printer_io;
+	struct usb_gadget	*gadget;
+	s8			interface;
+	struct usb_ep		*in_ep, *out_ep;
+
+	struct list_head	rx_reqs;	/* List of free RX structs */
+	struct list_head	rx_reqs_active;	/* List of Active RX xfers */
+	struct list_head	rx_buffers;	/* List of completed xfers */
+	/* wait until there is data to be read. */
+	wait_queue_head_t	rx_wait;
+	struct list_head	tx_reqs;	/* List of free TX structs */
+	struct list_head	tx_reqs_active; /* List of Active TX xfers */
+	/* Wait until there are write buffers available to use. */
+	wait_queue_head_t	tx_wait;
+	/* Wait until all write buffers have been sent. */
+	wait_queue_head_t	tx_flush_wait;
+	struct usb_request	*current_rx_req;
+	size_t			current_rx_bytes;
+	u8			*current_rx_buf;
+	u8			printer_status;
+	u8			reset_printer;
+	int			minor;
+	struct cdev		printer_cdev;
+	u8			printer_cdev_open;
+	wait_queue_head_t	wait;
+	unsigned		q_len;
+	char			*pnp_string;	/* We don't own memory! */
+	struct usb_function	function;
+};
+
+static inline struct printer_dev *func_to_printer(struct usb_function *f)
+{
+	return container_of(f, struct printer_dev, function);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * DESCRIPTORS ... most are static, but strings and (full) configuration
+ * descriptors are built on demand.
+ */
+
+/* holds our biggest descriptor */
+#define USB_DESC_BUFSIZE		256
+#define USB_BUFSIZE			8192
+
+static struct usb_interface_descriptor intf_desc = {
+	.bLength =		sizeof(intf_desc),
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bNumEndpoints =	2,
+	.bInterfaceClass =	USB_CLASS_PRINTER,
+	.bInterfaceSubClass =	1,	/* Printer Sub-Class */
+	.bInterfaceProtocol =	2,	/* Bi-Directional */
+	.iInterface =		0
+};
+
+static struct usb_endpoint_descriptor fs_ep_in_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK
+};
+
+static struct usb_endpoint_descriptor fs_ep_out_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK
+};
+
+static struct usb_descriptor_header *fs_printer_function[] = {
+	(struct usb_descriptor_header *) &intf_desc,
+	(struct usb_descriptor_header *) &fs_ep_in_desc,
+	(struct usb_descriptor_header *) &fs_ep_out_desc,
+	NULL
+};
+
+/*
+ * usb 2.0 devices need to expose both high speed and full speed
+ * descriptors, unless they only run at full speed.
+ */
+
+static struct usb_endpoint_descriptor hs_ep_in_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(512)
+};
+
+static struct usb_endpoint_descriptor hs_ep_out_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(512)
+};
+
+static struct usb_qualifier_descriptor dev_qualifier = {
+	.bLength =		sizeof(dev_qualifier),
+	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
+	.bcdUSB =		cpu_to_le16(0x0200),
+	.bDeviceClass =		USB_CLASS_PRINTER,
+	.bNumConfigurations =	1
+};
+
+static struct usb_descriptor_header *hs_printer_function[] = {
+	(struct usb_descriptor_header *) &intf_desc,
+	(struct usb_descriptor_header *) &hs_ep_in_desc,
+	(struct usb_descriptor_header *) &hs_ep_out_desc,
+	NULL
+};
+
+/*
+ * Added endpoint descriptors for 3.0 devices
+ */
+
+static struct usb_endpoint_descriptor ss_ep_in_desc = {
+	.bLength =              USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =      USB_DT_ENDPOINT,
+	.bmAttributes =         USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =       cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
+	.bLength =              sizeof(ss_ep_in_comp_desc),
+	.bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
+};
+
+static struct usb_endpoint_descriptor ss_ep_out_desc = {
+	.bLength =              USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =      USB_DT_ENDPOINT,
+	.bmAttributes =         USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =       cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
+	.bLength =              sizeof(ss_ep_out_comp_desc),
+	.bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
+};
+
+static struct usb_descriptor_header *ss_printer_function[] = {
+	(struct usb_descriptor_header *) &intf_desc,
+	(struct usb_descriptor_header *) &ss_ep_in_desc,
+	(struct usb_descriptor_header *) &ss_ep_in_comp_desc,
+	(struct usb_descriptor_header *) &ss_ep_out_desc,
+	(struct usb_descriptor_header *) &ss_ep_out_comp_desc,
+	NULL
+};
+
+/* maxpacket and other transfer characteristics vary by speed. */
+static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
+					struct usb_endpoint_descriptor *fs,
+					struct usb_endpoint_descriptor *hs,
+					struct usb_endpoint_descriptor *ss)
+{
+	switch (gadget->speed) {
+	case USB_SPEED_SUPER:
+		return ss;
+	case USB_SPEED_HIGH:
+		return hs;
+	default:
+		return fs;
+	}
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_request *
+printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
+{
+	struct usb_request	*req;
+
+	req = usb_ep_alloc_request(ep, gfp_flags);
+
+	if (req != NULL) {
+		req->length = len;
+		req->buf = kmalloc(len, gfp_flags);
+		if (req->buf == NULL) {
+			usb_ep_free_request(ep, req);
+			return NULL;
+		}
+	}
+
+	return req;
+}
+
+static void
+printer_req_free(struct usb_ep *ep, struct usb_request *req)
+{
+	if (ep != NULL && req != NULL) {
+		kfree(req->buf);
+		usb_ep_free_request(ep, req);
+	}
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void rx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct printer_dev	*dev = ep->driver_data;
+	int			status = req->status;
+	unsigned long		flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+
+	list_del_init(&req->list);	/* Remode from Active List */
+
+	switch (status) {
+
+	/* normal completion */
+	case 0:
+		if (req->actual > 0) {
+			list_add_tail(&req->list, &dev->rx_buffers);
+			DBG(dev, "G_Printer : rx length %d\n", req->actual);
+		} else {
+			list_add(&req->list, &dev->rx_reqs);
+		}
+		break;
+
+	/* software-driven interface shutdown */
+	case -ECONNRESET:		/* unlink */
+	case -ESHUTDOWN:		/* disconnect etc */
+		VDBG(dev, "rx shutdown, code %d\n", status);
+		list_add(&req->list, &dev->rx_reqs);
+		break;
+
+	/* for hardware automagic (such as pxa) */
+	case -ECONNABORTED:		/* endpoint reset */
+		DBG(dev, "rx %s reset\n", ep->name);
+		list_add(&req->list, &dev->rx_reqs);
+		break;
+
+	/* data overrun */
+	case -EOVERFLOW:
+		/* FALLTHROUGH */
+
+	default:
+		DBG(dev, "rx status %d\n", status);
+		list_add(&req->list, &dev->rx_reqs);
+		break;
+	}
+
+	wake_up_interruptible(&dev->rx_wait);
+	spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static void tx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct printer_dev	*dev = ep->driver_data;
+
+	switch (req->status) {
+	default:
+		VDBG(dev, "tx err %d\n", req->status);
+		/* FALLTHROUGH */
+	case -ECONNRESET:		/* unlink */
+	case -ESHUTDOWN:		/* disconnect etc */
+		break;
+	case 0:
+		break;
+	}
+
+	spin_lock(&dev->lock);
+	/* Take the request struct off the active list and put it on the
+	 * free list.
+	 */
+	list_del_init(&req->list);
+	list_add(&req->list, &dev->tx_reqs);
+	wake_up_interruptible(&dev->tx_wait);
+	if (likely(list_empty(&dev->tx_reqs_active)))
+		wake_up_interruptible(&dev->tx_flush_wait);
+
+	spin_unlock(&dev->lock);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int
+printer_open(struct inode *inode, struct file *fd)
+{
+	struct printer_dev	*dev;
+	unsigned long		flags;
+	int			ret = -EBUSY;
+
+	dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
+
+	spin_lock_irqsave(&dev->lock, flags);
+
+	if (!dev->printer_cdev_open) {
+		dev->printer_cdev_open = 1;
+		fd->private_data = dev;
+		ret = 0;
+		/* Change the printer status to show that it's on-line. */
+		dev->printer_status |= PRINTER_SELECTED;
+	}
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	DBG(dev, "printer_open returned %x\n", ret);
+	return ret;
+}
+
+static int
+printer_close(struct inode *inode, struct file *fd)
+{
+	struct printer_dev	*dev = fd->private_data;
+	unsigned long		flags;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	dev->printer_cdev_open = 0;
+	fd->private_data = NULL;
+	/* Change printer status to show that the printer is off-line. */
+	dev->printer_status &= ~PRINTER_SELECTED;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	DBG(dev, "printer_close\n");
+
+	return 0;
+}
+
+/* This function must be called with interrupts turned off. */
+static void
+setup_rx_reqs(struct printer_dev *dev)
+{
+	struct usb_request              *req;
+
+	while (likely(!list_empty(&dev->rx_reqs))) {
+		int error;
+
+		req = container_of(dev->rx_reqs.next,
+				struct usb_request, list);
+		list_del_init(&req->list);
+
+		/* The USB Host sends us whatever amount of data it wants to
+		 * so we always set the length field to the full USB_BUFSIZE.
+		 * If the amount of data is more than the read() caller asked
+		 * for it will be stored in the request buffer until it is
+		 * asked for by read().
+		 */
+		req->length = USB_BUFSIZE;
+		req->complete = rx_complete;
+
+		/* here, we unlock, and only unlock, to avoid deadlock. */
+		spin_unlock(&dev->lock);
+		error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
+		spin_lock(&dev->lock);
+		if (error) {
+			DBG(dev, "rx submit --> %d\n", error);
+			list_add(&req->list, &dev->rx_reqs);
+			break;
+		}
+		/* if the req is empty, then add it into dev->rx_reqs_active. */
+		else if (list_empty(&req->list))
+			list_add(&req->list, &dev->rx_reqs_active);
+	}
+}
+
+static ssize_t
+printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
+{
+	struct printer_dev		*dev = fd->private_data;
+	unsigned long			flags;
+	size_t				size;
+	size_t				bytes_copied;
+	struct usb_request		*req;
+	/* This is a pointer to the current USB rx request. */
+	struct usb_request		*current_rx_req;
+	/* This is the number of bytes in the current rx buffer. */
+	size_t				current_rx_bytes;
+	/* This is a pointer to the current rx buffer. */
+	u8				*current_rx_buf;
+
+	if (len == 0)
+		return -EINVAL;
+
+	DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
+
+	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
+	 * after we turn interrupts back on.
+	 */
+	dev->reset_printer = 0;
+
+	setup_rx_reqs(dev);
+
+	bytes_copied = 0;
+	current_rx_req = dev->current_rx_req;
+	current_rx_bytes = dev->current_rx_bytes;
+	current_rx_buf = dev->current_rx_buf;
+	dev->current_rx_req = NULL;
+	dev->current_rx_bytes = 0;
+	dev->current_rx_buf = NULL;
+
+	/* Check if there is any data in the read buffers. Please note that
+	 * current_rx_bytes is the number of bytes in the current rx buffer.
+	 * If it is zero then check if there are any other rx_buffers that
+	 * are on the completed list. We are only out of data if all rx
+	 * buffers are empty.
+	 */
+	if ((current_rx_bytes == 0) &&
+			(likely(list_empty(&dev->rx_buffers)))) {
+		/* Turn interrupts back on before sleeping. */
+		spin_unlock_irqrestore(&dev->lock, flags);
+
+		/*
+		 * If no data is available check if this is a NON-Blocking
+		 * call or not.
+		 */
+		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
+			mutex_unlock(&dev->lock_printer_io);
+			return -EAGAIN;
+		}
+
+		/* Sleep until data is available */
+		wait_event_interruptible(dev->rx_wait,
+				(likely(!list_empty(&dev->rx_buffers))));
+		spin_lock_irqsave(&dev->lock, flags);
+	}
+
+	/* We have data to return then copy it to the caller's buffer.*/
+	while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
+			&& len) {
+		if (current_rx_bytes == 0) {
+			req = container_of(dev->rx_buffers.next,
+					struct usb_request, list);
+			list_del_init(&req->list);
+
+			if (req->actual && req->buf) {
+				current_rx_req = req;
+				current_rx_bytes = req->actual;
+				current_rx_buf = req->buf;
+			} else {
+				list_add(&req->list, &dev->rx_reqs);
+				continue;
+			}
+		}
+
+		/* Don't leave irqs off while doing memory copies */
+		spin_unlock_irqrestore(&dev->lock, flags);
+
+		if (len > current_rx_bytes)
+			size = current_rx_bytes;
+		else
+			size = len;
+
+		size -= copy_to_user(buf, current_rx_buf, size);
+		bytes_copied += size;
+		len -= size;
+		buf += size;
+
+		spin_lock_irqsave(&dev->lock, flags);
+
+		/* We've disconnected or reset so return. */
+		if (dev->reset_printer) {
+			list_add(&current_rx_req->list, &dev->rx_reqs);
+			spin_unlock_irqrestore(&dev->lock, flags);
+			mutex_unlock(&dev->lock_printer_io);
+			return -EAGAIN;
+		}
+
+		/* If we not returning all the data left in this RX request
+		 * buffer then adjust the amount of data left in the buffer.
+		 * Othewise if we are done with this RX request buffer then
+		 * requeue it to get any incoming data from the USB host.
+		 */
+		if (size < current_rx_bytes) {
+			current_rx_bytes -= size;
+			current_rx_buf += size;
+		} else {
+			list_add(&current_rx_req->list, &dev->rx_reqs);
+			current_rx_bytes = 0;
+			current_rx_buf = NULL;
+			current_rx_req = NULL;
+		}
+	}
+
+	dev->current_rx_req = current_rx_req;
+	dev->current_rx_bytes = current_rx_bytes;
+	dev->current_rx_buf = current_rx_buf;
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+	mutex_unlock(&dev->lock_printer_io);
+
+	DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
+
+	if (bytes_copied)
+		return bytes_copied;
+	else
+		return -EAGAIN;
+}
+
+static ssize_t
+printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
+{
+	struct printer_dev	*dev = fd->private_data;
+	unsigned long		flags;
+	size_t			size;	/* Amount of data in a TX request. */
+	size_t			bytes_copied = 0;
+	struct usb_request	*req;
+
+	DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
+
+	if (len == 0)
+		return -EINVAL;
+
+	mutex_lock(&dev->lock_printer_io);
+	spin_lock_irqsave(&dev->lock, flags);
+
+	/* Check if a printer reset happens while we have interrupts on */
+	dev->reset_printer = 0;
+
+	/* Check if there is any available write buffers */
+	if (likely(list_empty(&dev->tx_reqs))) {
+		/* Turn interrupts back on before sleeping. */
+		spin_unlock_irqrestore(&dev->lock, flags);
+
+		/*
+		 * If write buffers are available check if this is
+		 * a NON-Blocking call or not.
+		 */
+		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
+			mutex_unlock(&dev->lock_printer_io);
+			return -EAGAIN;
+		}
+
+		/* Sleep until a write buffer is available */
+		wait_event_interruptible(dev->tx_wait,
+				(likely(!list_empty(&dev->tx_reqs))));
+		spin_lock_irqsave(&dev->lock, flags);
+	}
+
+	while (likely(!list_empty(&dev->tx_reqs)) && len) {
+
+		if (len > USB_BUFSIZE)
+			size = USB_BUFSIZE;
+		else
+			size = len;
+
+		req = container_of(dev->tx_reqs.next, struct usb_request,
+				list);
+		list_del_init(&req->list);
+
+		req->complete = tx_complete;
+		req->length = size;
+
+		/* Check if we need to send a zero length packet. */
+		if (len > size)
+			/* They will be more TX requests so no yet. */
+			req->zero = 0;
+		else
+			/* If the data amount is not a multiple of the
+			 * maxpacket size then send a zero length packet.
+			 */
+			req->zero = ((len % dev->in_ep->maxpacket) == 0);
+
+		/* Don't leave irqs off while doing memory copies */
+		spin_unlock_irqrestore(&dev->lock, flags);
+
+		if (copy_from_user(req->buf, buf, size)) {
+			list_add(&req->list, &dev->tx_reqs);
+			mutex_unlock(&dev->lock_printer_io);
+			return bytes_copied;
+		}
+
+		bytes_copied += size;
+		len -= size;
+		buf += size;
+
+		spin_lock_irqsave(&dev->lock, flags);
+
+		/* We've disconnected or reset so free the req and buffer */
+		if (dev->reset_printer) {
+			list_add(&req->list, &dev->tx_reqs);
+			spin_unlock_irqrestore(&dev->lock, flags);
+			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);
+			mutex_unlock(&dev->lock_printer_io);
+			return -EAGAIN;
+		}
+
+		list_add(&req->list, &dev->tx_reqs_active);
+
+	}
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+	mutex_unlock(&dev->lock_printer_io);
+
+	DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
+
+	if (bytes_copied)
+		return bytes_copied;
+	else
+		return -EAGAIN;
+}
+
+static int
+printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
+{
+	struct printer_dev	*dev = fd->private_data;
+	struct inode *inode = file_inode(fd);
+	unsigned long		flags;
+	int			tx_list_empty;
+
+	mutex_lock(&inode->i_mutex);
+	spin_lock_irqsave(&dev->lock, flags);
+	tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	if (!tx_list_empty) {
+		/* Sleep until all data has been sent */
+		wait_event_interruptible(dev->tx_flush_wait,
+				(likely(list_empty(&dev->tx_reqs_active))));
+	}
+	mutex_unlock(&inode->i_mutex);
+
+	return 0;
+}
+
+static unsigned int
+printer_poll(struct file *fd, poll_table *wait)
+{
+	struct printer_dev	*dev = fd->private_data;
+	unsigned long		flags;
+	int			status = 0;
+
+	mutex_lock(&dev->lock_printer_io);
+	spin_lock_irqsave(&dev->lock, flags);
+	setup_rx_reqs(dev);
+	spin_unlock_irqrestore(&dev->lock, flags);
+	mutex_unlock(&dev->lock_printer_io);
+
+	poll_wait(fd, &dev->rx_wait, wait);
+	poll_wait(fd, &dev->tx_wait, wait);
+
+	spin_lock_irqsave(&dev->lock, flags);
+	if (likely(!list_empty(&dev->tx_reqs)))
+		status |= POLLOUT | POLLWRNORM;
+
+	if (likely(dev->current_rx_bytes) ||
+			likely(!list_empty(&dev->rx_buffers)))
+		status |= POLLIN | POLLRDNORM;
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	return status;
+}
+
+static long
+printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
+{
+	struct printer_dev	*dev = fd->private_data;
+	unsigned long		flags;
+	int			status = 0;
+
+	DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
+
+	/* handle ioctls */
+
+	spin_lock_irqsave(&dev->lock, flags);
+
+	switch (code) {
+	case GADGET_GET_PRINTER_STATUS:
+		status = (int)dev->printer_status;
+		break;
+	case GADGET_SET_PRINTER_STATUS:
+		dev->printer_status = (u8)arg;
+		break;
+	default:
+		/* could not handle ioctl */
+		DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
+				code);
+		status = -ENOTTY;
+	}
+
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	return status;
+}
+
+/* used after endpoint configuration */
+static const struct file_operations printer_io_operations = {
+	.owner =	THIS_MODULE,
+	.open =		printer_open,
+	.read =		printer_read,
+	.write =	printer_write,
+	.fsync =	printer_fsync,
+	.poll =		printer_poll,
+	.unlocked_ioctl = printer_ioctl,
+	.release =	printer_close,
+	.llseek =	noop_llseek,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int
+set_printer_interface(struct printer_dev *dev)
+{
+	int			result = 0;
+
+	dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
+				&ss_ep_in_desc);
+	dev->in_ep->driver_data = dev;
+
+	dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
+				    &hs_ep_out_desc, &ss_ep_out_desc);
+	dev->out_ep->driver_data = dev;
+
+	result = usb_ep_enable(dev->in_ep);
+	if (result != 0) {
+		DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
+		goto done;
+	}
+
+	result = usb_ep_enable(dev->out_ep);
+	if (result != 0) {
+		DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
+		goto done;
+	}
+
+done:
+	/* on error, disable any endpoints  */
+	if (result != 0) {
+		(void) usb_ep_disable(dev->in_ep);
+		(void) usb_ep_disable(dev->out_ep);
+		dev->in_ep->desc = NULL;
+		dev->out_ep->desc = NULL;
+	}
+
+	/* caller is responsible for cleanup on error */
+	return result;
+}
+
+static void printer_reset_interface(struct printer_dev *dev)
+{
+	if (dev->interface < 0)
+		return;
+
+	DBG(dev, "%s\n", __func__);
+
+	if (dev->in_ep->desc)
+		usb_ep_disable(dev->in_ep);
+
+	if (dev->out_ep->desc)
+		usb_ep_disable(dev->out_ep);
+
+	dev->in_ep->desc = NULL;
+	dev->out_ep->desc = NULL;
+	dev->interface = -1;
+}
+
+/* Change our operational Interface. */
+static int set_interface(struct printer_dev *dev, unsigned number)
+{
+	int			result = 0;
+
+	/* Free the current interface */
+	printer_reset_interface(dev);
+
+	result = set_printer_interface(dev);
+	if (result)
+		printer_reset_interface(dev);
+	else
+		dev->interface = number;
+
+	if (!result)
+		INFO(dev, "Using interface %x\n", number);
+
+	return result;
+}
+
+static void printer_soft_reset(struct printer_dev *dev)
+{
+	struct usb_request	*req;
+
+	INFO(dev, "Received Printer Reset Request\n");
+
+	if (usb_ep_disable(dev->in_ep))
+		DBG(dev, "Failed to disable USB in_ep\n");
+	if (usb_ep_disable(dev->out_ep))
+		DBG(dev, "Failed to disable USB out_ep\n");
+
+	if (dev->current_rx_req != NULL) {
+		list_add(&dev->current_rx_req->list, &dev->rx_reqs);
+		dev->current_rx_req = NULL;
+	}
+	dev->current_rx_bytes = 0;
+	dev->current_rx_buf = NULL;
+	dev->reset_printer = 1;
+
+	while (likely(!(list_empty(&dev->rx_buffers)))) {
+		req = container_of(dev->rx_buffers.next, struct usb_request,
+				list);
+		list_del_init(&req->list);
+		list_add(&req->list, &dev->rx_reqs);
+	}
+
+	while (likely(!(list_empty(&dev->rx_reqs_active)))) {
+		req = container_of(dev->rx_buffers.next, struct usb_request,
+				list);
+		list_del_init(&req->list);
+		list_add(&req->list, &dev->rx_reqs);
+	}
+
+	while (likely(!(list_empty(&dev->tx_reqs_active)))) {
+		req = container_of(dev->tx_reqs_active.next,
+				struct usb_request, list);
+		list_del_init(&req->list);
+		list_add(&req->list, &dev->tx_reqs);
+	}
+
+	if (usb_ep_enable(dev->in_ep))
+		DBG(dev, "Failed to enable USB in_ep\n");
+	if (usb_ep_enable(dev->out_ep))
+		DBG(dev, "Failed to enable USB out_ep\n");
+
+	wake_up_interruptible(&dev->rx_wait);
+	wake_up_interruptible(&dev->tx_wait);
+	wake_up_interruptible(&dev->tx_flush_wait);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static bool gprinter_req_match(struct usb_function *f,
+			       const struct usb_ctrlrequest *ctrl)
+{
+	struct printer_dev	*dev = func_to_printer(f);
+	u16			w_index = le16_to_cpu(ctrl->wIndex);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u16			w_length = le16_to_cpu(ctrl->wLength);
+
+	if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
+	    (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
+		return false;
+
+	switch (ctrl->bRequest) {
+	case GET_DEVICE_ID:
+		w_index >>= 8;
+		if (w_length <= PNP_STRING_LEN &&
+		    (USB_DIR_IN & ctrl->bRequestType))
+			break;
+		return false;
+	case GET_PORT_STATUS:
+		if (!w_value && w_length == 1 &&
+		    (USB_DIR_IN & ctrl->bRequestType))
+			break;
+		return false;
+	case SOFT_RESET:
+		if (!w_value && !w_length &&
+		   !(USB_DIR_IN & ctrl->bRequestType))
+			break;
+		/* fall through */
+	default:
+		return false;
+	}
+	return w_index == dev->interface;
+}
+
+/*
+ * The setup() callback implements all the ep0 functionality that's not
+ * handled lower down.
+ */
+static int printer_func_setup(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct printer_dev *dev = func_to_printer(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request	*req = cdev->req;
+	int			value = -EOPNOTSUPP;
+	u16			wIndex = le16_to_cpu(ctrl->wIndex);
+	u16			wValue = le16_to_cpu(ctrl->wValue);
+	u16			wLength = le16_to_cpu(ctrl->wLength);
+
+	DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
+		ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
+
+	switch (ctrl->bRequestType&USB_TYPE_MASK) {
+	case USB_TYPE_CLASS:
+		switch (ctrl->bRequest) {
+		case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
+			/* Only one printer interface is supported. */
+			if ((wIndex>>8) != dev->interface)
+				break;
+
+			value = (dev->pnp_string[0] << 8) | dev->pnp_string[1];
+			memcpy(req->buf, dev->pnp_string, value);
+			DBG(dev, "1284 PNP String: %x %s\n", value,
+					&dev->pnp_string[2]);
+			break;
+
+		case GET_PORT_STATUS: /* Get Port Status */
+			/* Only one printer interface is supported. */
+			if (wIndex != dev->interface)
+				break;
+
+			*(u8 *)req->buf = dev->printer_status;
+			value = min_t(u16, wLength, 1);
+			break;
+
+		case SOFT_RESET: /* Soft Reset */
+			/* Only one printer interface is supported. */
+			if (wIndex != dev->interface)
+				break;
+
+			printer_soft_reset(dev);
+
+			value = 0;
+			break;
+
+		default:
+			goto unknown;
+		}
+		break;
+
+	default:
+unknown:
+		VDBG(dev,
+			"unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			wValue, wIndex, wLength);
+		break;
+	}
+	/* host either stalls (value < 0) or reports success */
+	if (value >= 0) {
+		req->length = value;
+		req->zero = value < wLength;
+		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+		if (value < 0) {
+			ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
+			req->status = 0;
+		}
+	}
+	return value;
+}
+
+static int printer_func_bind(struct usb_configuration *c,
+		struct usb_function *f)
+{
+	struct usb_gadget *gadget = c->cdev->gadget;
+	struct printer_dev *dev = func_to_printer(f);
+	struct device *pdev;
+	struct usb_composite_dev *cdev = c->cdev;
+	struct usb_ep *in_ep;
+	struct usb_ep *out_ep = NULL;
+	struct usb_request *req;
+	dev_t devt;
+	int id;
+	int ret;
+	u32 i;
+
+	id = usb_interface_id(c, f);
+	if (id < 0)
+		return id;
+	intf_desc.bInterfaceNumber = id;
+
+	/* finish hookup to lower layer ... */
+	dev->gadget = gadget;
+
+	/* all we really need is bulk IN/OUT */
+	in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
+	if (!in_ep) {
+autoconf_fail:
+		dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
+			cdev->gadget->name);
+		return -ENODEV;
+	}
+	in_ep->driver_data = in_ep;	/* claim */
+
+	out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
+	if (!out_ep)
+		goto autoconf_fail;
+	out_ep->driver_data = out_ep;	/* claim */
+
+	/* assumes that all endpoints are dual-speed */
+	hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
+	hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
+	ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
+	ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
+
+	ret = usb_assign_descriptors(f, fs_printer_function,
+			hs_printer_function, ss_printer_function);
+	if (ret)
+		return ret;
+
+	dev->in_ep = in_ep;
+	dev->out_ep = out_ep;
+
+	ret = -ENOMEM;
+	for (i = 0; i < dev->q_len; i++) {
+		req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
+		if (!req)
+			goto fail_tx_reqs;
+		list_add(&req->list, &dev->tx_reqs);
+	}
+
+	for (i = 0; i < dev->q_len; i++) {
+		req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
+		if (!req)
+			goto fail_rx_reqs;
+		list_add(&req->list, &dev->rx_reqs);
+	}
+
+	/* Setup the sysfs files for the printer gadget. */
+	devt = MKDEV(major, dev->minor);
+	pdev = device_create(usb_gadget_class, NULL, devt,
+				  NULL, "g_printer%d", dev->minor);
+	if (IS_ERR(pdev)) {
+		ERROR(dev, "Failed to create device: g_printer\n");
+		ret = PTR_ERR(pdev);
+		goto fail_rx_reqs;
+	}
+
+	/*
+	 * Register a character device as an interface to a user mode
+	 * program that handles the printer specific functionality.
+	 */
+	cdev_init(&dev->printer_cdev, &printer_io_operations);
+	dev->printer_cdev.owner = THIS_MODULE;
+	ret = cdev_add(&dev->printer_cdev, devt, 1);
+	if (ret) {
+		ERROR(dev, "Failed to open char device\n");
+		goto fail_cdev_add;
+	}
+
+	return 0;
+
+fail_cdev_add:
+	device_destroy(usb_gadget_class, devt);
+
+fail_rx_reqs:
+	while (!list_empty(&dev->rx_reqs)) {
+		req = container_of(dev->rx_reqs.next, struct usb_request, list);
+		list_del(&req->list);
+		printer_req_free(dev->out_ep, req);
+	}
+
+fail_tx_reqs:
+	while (!list_empty(&dev->tx_reqs)) {
+		req = container_of(dev->tx_reqs.next, struct usb_request, list);
+		list_del(&req->list);
+		printer_req_free(dev->in_ep, req);
+	}
+
+	return ret;
+
+}
+
+static int printer_func_set_alt(struct usb_function *f,
+		unsigned intf, unsigned alt)
+{
+	struct printer_dev *dev = func_to_printer(f);
+	int ret = -ENOTSUPP;
+
+	if (!alt)
+		ret = set_interface(dev, intf);
+
+	return ret;
+}
+
+static void printer_func_disable(struct usb_function *f)
+{
+	struct printer_dev *dev = func_to_printer(f);
+	unsigned long		flags;
+
+	DBG(dev, "%s\n", __func__);
+
+	spin_lock_irqsave(&dev->lock, flags);
+	printer_reset_interface(dev);
+	spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static inline struct f_printer_opts
+*to_f_printer_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_printer_opts,
+			    func_inst.group);
+}
+
+CONFIGFS_ATTR_STRUCT(f_printer_opts);
+CONFIGFS_ATTR_OPS(f_printer_opts);
+
+static void printer_attr_release(struct config_item *item)
+{
+	struct f_printer_opts *opts = to_f_printer_opts(item);
+
+	usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations printer_item_ops = {
+	.release	= printer_attr_release,
+	.show_attribute	= f_printer_opts_attr_show,
+	.store_attribute = f_printer_opts_attr_store,
+};
+
+static ssize_t f_printer_opts_pnp_string_show(struct f_printer_opts *opts,
+					      char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = strlcpy(page, opts->pnp_string + 2, PNP_STRING_LEN - 2);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_printer_opts_pnp_string_store(struct f_printer_opts *opts,
+					       const char *page, size_t len)
+{
+	int result, l;
+
+	mutex_lock(&opts->lock);
+	result = strlcpy(opts->pnp_string + 2, page, PNP_STRING_LEN - 2);
+	l = strlen(opts->pnp_string + 2) + 2;
+	opts->pnp_string[0] = (l >> 8) & 0xFF;
+	opts->pnp_string[1] = l & 0xFF;
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static struct f_printer_opts_attribute f_printer_opts_pnp_string =
+	__CONFIGFS_ATTR(pnp_string, S_IRUGO | S_IWUSR,
+			f_printer_opts_pnp_string_show,
+			f_printer_opts_pnp_string_store);
+
+static ssize_t f_printer_opts_q_len_show(struct f_printer_opts *opts,
+					 char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d\n", opts->q_len);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_printer_opts_q_len_store(struct f_printer_opts *opts,
+					  const char *page, size_t len)
+{
+	int ret;
+	u16 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou16(page, 0, &num);
+	if (ret)
+		goto end;
+
+	opts->q_len = (unsigned)num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_printer_opts_attribute f_printer_opts_q_len =
+	__CONFIGFS_ATTR(q_len, S_IRUGO | S_IWUSR, f_printer_opts_q_len_show,
+			f_printer_opts_q_len_store);
+
+static struct configfs_attribute *printer_attrs[] = {
+	&f_printer_opts_pnp_string.attr,
+	&f_printer_opts_q_len.attr,
+	NULL,
+};
+
+static struct config_item_type printer_func_type = {
+	.ct_item_ops	= &printer_item_ops,
+	.ct_attrs	= printer_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static inline int gprinter_get_minor(void)
+{
+	return ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
+}
+
+static inline void gprinter_put_minor(int minor)
+{
+	ida_simple_remove(&printer_ida, minor);
+}
+
+static int gprinter_setup(int);
+static void gprinter_cleanup(void);
+
+static void gprinter_free_inst(struct usb_function_instance *f)
+{
+	struct f_printer_opts *opts;
+
+	opts = container_of(f, struct f_printer_opts, func_inst);
+
+	mutex_lock(&printer_ida_lock);
+
+	gprinter_put_minor(opts->minor);
+	if (idr_is_empty(&printer_ida.idr))
+		gprinter_cleanup();
+
+	mutex_unlock(&printer_ida_lock);
+
+	kfree(opts);
+}
+
+static struct usb_function_instance *gprinter_alloc_inst(void)
+{
+	struct f_printer_opts *opts;
+	struct usb_function_instance *ret;
+	int status = 0;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_init(&opts->lock);
+	opts->func_inst.free_func_inst = gprinter_free_inst;
+	ret = &opts->func_inst;
+
+	mutex_lock(&printer_ida_lock);
+
+	if (idr_is_empty(&printer_ida.idr)) {
+		status = gprinter_setup(PRINTER_MINORS);
+		if (status) {
+			ret = ERR_PTR(status);
+			kfree(opts);
+			goto unlock;
+		}
+	}
+
+	opts->minor = gprinter_get_minor();
+	if (opts->minor < 0) {
+		ret = ERR_PTR(opts->minor);
+		kfree(opts);
+		if (idr_is_empty(&printer_ida.idr))
+			gprinter_cleanup();
+		goto unlock;
+	}
+	config_group_init_type_name(&opts->func_inst.group, "",
+				    &printer_func_type);
+
+unlock:
+	mutex_unlock(&printer_ida_lock);
+	return ret;
+}
+
+static void gprinter_free(struct usb_function *f)
+{
+	struct printer_dev *dev = func_to_printer(f);
+	struct f_printer_opts *opts;
+
+	opts = container_of(f->fi, struct f_printer_opts, func_inst);
+	kfree(dev);
+	mutex_lock(&opts->lock);
+	--opts->refcnt;
+	mutex_unlock(&opts->lock);
+}
+
+static void printer_func_unbind(struct usb_configuration *c,
+		struct usb_function *f)
+{
+	struct printer_dev	*dev;
+	struct usb_request	*req;
+
+	dev = func_to_printer(f);
+
+	device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
+
+	/* Remove Character Device */
+	cdev_del(&dev->printer_cdev);
+
+	/* we must already have been disconnected ... no i/o may be active */
+	WARN_ON(!list_empty(&dev->tx_reqs_active));
+	WARN_ON(!list_empty(&dev->rx_reqs_active));
+
+	/* Free all memory for this driver. */
+	while (!list_empty(&dev->tx_reqs)) {
+		req = container_of(dev->tx_reqs.next, struct usb_request,
+				list);
+		list_del(&req->list);
+		printer_req_free(dev->in_ep, req);
+	}
+
+	if (dev->current_rx_req != NULL)
+		printer_req_free(dev->out_ep, dev->current_rx_req);
+
+	while (!list_empty(&dev->rx_reqs)) {
+		req = container_of(dev->rx_reqs.next,
+				struct usb_request, list);
+		list_del(&req->list);
+		printer_req_free(dev->out_ep, req);
+	}
+
+	while (!list_empty(&dev->rx_buffers)) {
+		req = container_of(dev->rx_buffers.next,
+				struct usb_request, list);
+		list_del(&req->list);
+		printer_req_free(dev->out_ep, req);
+	}
+	usb_free_all_descriptors(f);
+}
+
+static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
+{
+	struct printer_dev	*dev;
+	struct f_printer_opts	*opts;
+
+	opts = container_of(fi, struct f_printer_opts, func_inst);
+
+	mutex_lock(&opts->lock);
+	if (opts->minor >= minors) {
+		mutex_unlock(&opts->lock);
+		return ERR_PTR(-ENOENT);
+	}
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev) {
+		mutex_unlock(&opts->lock);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	++opts->refcnt;
+	dev->minor = opts->minor;
+	dev->pnp_string = opts->pnp_string;
+	dev->q_len = opts->q_len;
+	mutex_unlock(&opts->lock);
+
+	dev->function.name = "printer";
+	dev->function.bind = printer_func_bind;
+	dev->function.setup = printer_func_setup;
+	dev->function.unbind = printer_func_unbind;
+	dev->function.set_alt = printer_func_set_alt;
+	dev->function.disable = printer_func_disable;
+	dev->function.req_match = gprinter_req_match;
+	dev->function.free_func = gprinter_free;
+
+	INIT_LIST_HEAD(&dev->tx_reqs);
+	INIT_LIST_HEAD(&dev->rx_reqs);
+	INIT_LIST_HEAD(&dev->rx_buffers);
+	INIT_LIST_HEAD(&dev->tx_reqs_active);
+	INIT_LIST_HEAD(&dev->rx_reqs_active);
+
+	spin_lock_init(&dev->lock);
+	mutex_init(&dev->lock_printer_io);
+	init_waitqueue_head(&dev->rx_wait);
+	init_waitqueue_head(&dev->tx_wait);
+	init_waitqueue_head(&dev->tx_flush_wait);
+
+	dev->interface = -1;
+	dev->printer_cdev_open = 0;
+	dev->printer_status = PRINTER_NOT_ERROR;
+	dev->current_rx_req = NULL;
+	dev->current_rx_bytes = 0;
+	dev->current_rx_buf = NULL;
+
+	return &dev->function;
+}
+
+DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Craig Nadler");
+
+static int gprinter_setup(int count)
+{
+	int status;
+	dev_t devt;
+
+	usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
+	if (IS_ERR(usb_gadget_class)) {
+		status = PTR_ERR(usb_gadget_class);
+		usb_gadget_class = NULL;
+		pr_err("unable to create usb_gadget class %d\n", status);
+		return status;
+	}
+
+	status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
+	if (status) {
+		pr_err("alloc_chrdev_region %d\n", status);
+		class_destroy(usb_gadget_class);
+		usb_gadget_class = NULL;
+		return status;
+	}
+
+	major = MAJOR(devt);
+	minors = count;
+
+	return status;
+}
+
+static void gprinter_cleanup(void)
+{
+	if (major) {
+		unregister_chrdev_region(MKDEV(major, 0), minors);
+		major = minors = 0;
+	}
+	class_destroy(usb_gadget_class);
+	usb_gadget_class = NULL;
+}
diff --git a/drivers/usb/gadget/function/u_printer.h b/drivers/usb/gadget/function/u_printer.h
new file mode 100644
index 000000000000..0e2c49d4274e
--- /dev/null
+++ b/drivers/usb/gadget/function/u_printer.h
@@ -0,0 +1,37 @@
+/*
+ * u_printer.h
+ *
+ * Utility definitions for the printer function
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef U_PRINTER_H
+#define U_PRINTER_H
+
+#include <linux/usb/composite.h>
+
+#define PNP_STRING_LEN			1024
+
+struct f_printer_opts {
+	struct usb_function_instance	func_inst;
+	int				minor;
+	char				pnp_string[PNP_STRING_LEN];
+	unsigned			q_len;
+
+	/*
+	 * Protect the data from concurrent access by read/write
+	 * and create symlink/remove symlink
+	 */
+	struct mutex			lock;
+	int				refcnt;
+};
+
+#endif /* U_PRINTER_H */
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index 491082aaf103..89179ab20c10 100644
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -912,7 +912,7 @@ static int gs_put_char(struct tty_struct *tty, unsigned char ch)
 	unsigned long	flags;
 	int		status;
 
-	pr_vdebug("gs_put_char: (%d,%p) char=0x%x, called from %pf\n",
+	pr_vdebug("gs_put_char: (%d,%p) char=0x%x, called from %ps\n",
 		port->port_num, tty, ch, __builtin_return_address(0));
 
 	spin_lock_irqsave(&port->port_lock, flags);
diff --git a/drivers/usb/gadget/legacy/Kconfig b/drivers/usb/gadget/legacy/Kconfig
index 113c87e22117..d5a7102de696 100644
--- a/drivers/usb/gadget/legacy/Kconfig
+++ b/drivers/usb/gadget/legacy/Kconfig
@@ -301,6 +301,7 @@ config USB_MIDI_GADGET
 config USB_G_PRINTER
 	tristate "Printer Gadget"
 	select USB_LIBCOMPOSITE
+	select USB_F_PRINTER
 	help
 	  The Printer Gadget channels data between the USB host and a
 	  userspace program driving the print engine. The user space
diff --git a/drivers/usb/gadget/legacy/printer.c b/drivers/usb/gadget/legacy/printer.c
index 90545980542f..d5b6ee725a2a 100644
--- a/drivers/usb/gadget/legacy/printer.c
+++ b/drivers/usb/gadget/legacy/printer.c
@@ -12,29 +12,7 @@
 
 #include <linux/module.h>
 #include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/ioport.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/mutex.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/timer.h>
-#include <linux/list.h>
-#include <linux/interrupt.h>
-#include <linux/device.h>
-#include <linux/moduleparam.h>
-#include <linux/fs.h>
-#include <linux/poll.h>
-#include <linux/types.h>
-#include <linux/ctype.h>
-#include <linux/cdev.h>
-
 #include <asm/byteorder.h>
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/uaccess.h>
-#include <asm/unaligned.h>
 
 #include <linux/usb/ch9.h>
 #include <linux/usb/composite.h>
@@ -46,50 +24,12 @@
 USB_GADGET_COMPOSITE_OPTIONS();
 
 #define DRIVER_DESC		"Printer Gadget"
-#define DRIVER_VERSION		"2007 OCT 06"
+#define DRIVER_VERSION		"2015 FEB 17"
 
-static DEFINE_MUTEX(printer_mutex);
 static const char shortname [] = "printer";
 static const char driver_desc [] = DRIVER_DESC;
 
-static dev_t g_printer_devno;
-
-static struct class *usb_gadget_class;
-
-/*-------------------------------------------------------------------------*/
-
-struct printer_dev {
-	spinlock_t		lock;		/* lock this structure */
-	/* lock buffer lists during read/write calls */
-	struct mutex		lock_printer_io;
-	struct usb_gadget	*gadget;
-	s8			interface;
-	struct usb_ep		*in_ep, *out_ep;
-
-	struct list_head	rx_reqs;	/* List of free RX structs */
-	struct list_head	rx_reqs_active;	/* List of Active RX xfers */
-	struct list_head	rx_buffers;	/* List of completed xfers */
-	/* wait until there is data to be read. */
-	wait_queue_head_t	rx_wait;
-	struct list_head	tx_reqs;	/* List of free TX structs */
-	struct list_head	tx_reqs_active; /* List of Active TX xfers */
-	/* Wait until there are write buffers available to use. */
-	wait_queue_head_t	tx_wait;
-	/* Wait until all write buffers have been sent. */
-	wait_queue_head_t	tx_flush_wait;
-	struct usb_request	*current_rx_req;
-	size_t			current_rx_bytes;
-	u8			*current_rx_buf;
-	u8			printer_status;
-	u8			reset_printer;
-	struct cdev		printer_cdev;
-	struct device		*pdev;
-	u8			printer_cdev_open;
-	wait_queue_head_t	wait;
-	struct usb_function	function;
-};
-
-static struct printer_dev usb_printer_gadget;
+#include "u_printer.h"
 
 /*-------------------------------------------------------------------------*/
 
@@ -120,6 +60,9 @@ module_param(qlen, uint, S_IRUGO|S_IWUSR);
 
 #define QLEN	qlen
 
+static struct usb_function_instance *fi_printer;
+static struct usb_function *f_printer;
+
 /*-------------------------------------------------------------------------*/
 
 /*
@@ -127,10 +70,6 @@ module_param(qlen, uint, S_IRUGO|S_IWUSR);
  * descriptors are built on demand.
  */
 
-/* holds our biggest descriptor */
-#define USB_DESC_BUFSIZE		256
-#define USB_BUFSIZE			8192
-
 static struct usb_device_descriptor device_desc = {
 	.bLength =		sizeof device_desc,
 	.bDescriptorType =	USB_DT_DEVICE,
@@ -143,108 +82,6 @@ static struct usb_device_descriptor device_desc = {
 	.bNumConfigurations =	1
 };
 
-static struct usb_interface_descriptor intf_desc = {
-	.bLength =		sizeof intf_desc,
-	.bDescriptorType =	USB_DT_INTERFACE,
-	.bNumEndpoints =	2,
-	.bInterfaceClass =	USB_CLASS_PRINTER,
-	.bInterfaceSubClass =	1,	/* Printer Sub-Class */
-	.bInterfaceProtocol =	2,	/* Bi-Directional */
-	.iInterface =		0
-};
-
-static struct usb_endpoint_descriptor fs_ep_in_desc = {
-	.bLength =		USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =	USB_DT_ENDPOINT,
-	.bEndpointAddress =	USB_DIR_IN,
-	.bmAttributes =		USB_ENDPOINT_XFER_BULK
-};
-
-static struct usb_endpoint_descriptor fs_ep_out_desc = {
-	.bLength =		USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =	USB_DT_ENDPOINT,
-	.bEndpointAddress =	USB_DIR_OUT,
-	.bmAttributes =		USB_ENDPOINT_XFER_BULK
-};
-
-static struct usb_descriptor_header *fs_printer_function[] = {
-	(struct usb_descriptor_header *) &intf_desc,
-	(struct usb_descriptor_header *) &fs_ep_in_desc,
-	(struct usb_descriptor_header *) &fs_ep_out_desc,
-	NULL
-};
-
-/*
- * usb 2.0 devices need to expose both high speed and full speed
- * descriptors, unless they only run at full speed.
- */
-
-static struct usb_endpoint_descriptor hs_ep_in_desc = {
-	.bLength =		USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =	USB_DT_ENDPOINT,
-	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
-	.wMaxPacketSize =	cpu_to_le16(512)
-};
-
-static struct usb_endpoint_descriptor hs_ep_out_desc = {
-	.bLength =		USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =	USB_DT_ENDPOINT,
-	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
-	.wMaxPacketSize =	cpu_to_le16(512)
-};
-
-static struct usb_qualifier_descriptor dev_qualifier = {
-	.bLength =		sizeof dev_qualifier,
-	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
-	.bcdUSB =		cpu_to_le16(0x0200),
-	.bDeviceClass =		USB_CLASS_PRINTER,
-	.bNumConfigurations =	1
-};
-
-static struct usb_descriptor_header *hs_printer_function[] = {
-	(struct usb_descriptor_header *) &intf_desc,
-	(struct usb_descriptor_header *) &hs_ep_in_desc,
-	(struct usb_descriptor_header *) &hs_ep_out_desc,
-	NULL
-};
-
-/*
- * Added endpoint descriptors for 3.0 devices
- */
-
-static struct usb_endpoint_descriptor ss_ep_in_desc = {
-	.bLength =              USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =      USB_DT_ENDPOINT,
-	.bmAttributes =         USB_ENDPOINT_XFER_BULK,
-	.wMaxPacketSize =       cpu_to_le16(1024),
-};
-
-static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
-	.bLength =              sizeof(ss_ep_in_comp_desc),
-	.bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
-};
-
-static struct usb_endpoint_descriptor ss_ep_out_desc = {
-	.bLength =              USB_DT_ENDPOINT_SIZE,
-	.bDescriptorType =      USB_DT_ENDPOINT,
-	.bmAttributes =         USB_ENDPOINT_XFER_BULK,
-	.wMaxPacketSize =       cpu_to_le16(1024),
-};
-
-static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
-	.bLength =              sizeof(ss_ep_out_comp_desc),
-	.bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
-};
-
-static struct usb_descriptor_header *ss_printer_function[] = {
-	(struct usb_descriptor_header *) &intf_desc,
-	(struct usb_descriptor_header *) &ss_ep_in_desc,
-	(struct usb_descriptor_header *) &ss_ep_in_comp_desc,
-	(struct usb_descriptor_header *) &ss_ep_out_desc,
-	(struct usb_descriptor_header *) &ss_ep_out_comp_desc,
-	NULL
-};
-
 static struct usb_otg_descriptor otg_descriptor = {
 	.bLength =              sizeof otg_descriptor,
 	.bDescriptorType =      USB_DT_OTG,
@@ -256,29 +93,13 @@ static const struct usb_descriptor_header *otg_desc[] = {
 	NULL,
 };
 
-/* maxpacket and other transfer characteristics vary by speed. */
-static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
-					struct usb_endpoint_descriptor *fs,
-					struct usb_endpoint_descriptor *hs,
-					struct usb_endpoint_descriptor *ss)
-{
-	switch (gadget->speed) {
-	case USB_SPEED_SUPER:
-		return ss;
-	case USB_SPEED_HIGH:
-		return hs;
-	default:
-		return fs;
-	}
-}
-
 /*-------------------------------------------------------------------------*/
 
 /* descriptors that are built on-demand */
 
 static char				product_desc [40] = DRIVER_DESC;
 static char				serial_num [40] = "1";
-static char				pnp_string [1024] =
+static char				pnp_string[PNP_STRING_LEN] =
 	"XXMFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
 
 /* static strings, in UTF-8 */
@@ -299,921 +120,19 @@ static struct usb_gadget_strings *dev_strings[] = {
 	NULL,
 };
 
-/*-------------------------------------------------------------------------*/
-
-static struct usb_request *
-printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
-{
-	struct usb_request	*req;
-
-	req = usb_ep_alloc_request(ep, gfp_flags);
-
-	if (req != NULL) {
-		req->length = len;
-		req->buf = kmalloc(len, gfp_flags);
-		if (req->buf == NULL) {
-			usb_ep_free_request(ep, req);
-			return NULL;
-		}
-	}
-
-	return req;
-}
-
-static void
-printer_req_free(struct usb_ep *ep, struct usb_request *req)
-{
-	if (ep != NULL && req != NULL) {
-		kfree(req->buf);
-		usb_ep_free_request(ep, req);
-	}
-}
-
-/*-------------------------------------------------------------------------*/
-
-static void rx_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct printer_dev	*dev = ep->driver_data;
-	int			status = req->status;
-	unsigned long		flags;
-
-	spin_lock_irqsave(&dev->lock, flags);
-
-	list_del_init(&req->list);	/* Remode from Active List */
-
-	switch (status) {
-
-	/* normal completion */
-	case 0:
-		if (req->actual > 0) {
-			list_add_tail(&req->list, &dev->rx_buffers);
-			DBG(dev, "G_Printer : rx length %d\n", req->actual);
-		} else {
-			list_add(&req->list, &dev->rx_reqs);
-		}
-		break;
-
-	/* software-driven interface shutdown */
-	case -ECONNRESET:		/* unlink */
-	case -ESHUTDOWN:		/* disconnect etc */
-		VDBG(dev, "rx shutdown, code %d\n", status);
-		list_add(&req->list, &dev->rx_reqs);
-		break;
-
-	/* for hardware automagic (such as pxa) */
-	case -ECONNABORTED:		/* endpoint reset */
-		DBG(dev, "rx %s reset\n", ep->name);
-		list_add(&req->list, &dev->rx_reqs);
-		break;
-
-	/* data overrun */
-	case -EOVERFLOW:
-		/* FALLTHROUGH */
-
-	default:
-		DBG(dev, "rx status %d\n", status);
-		list_add(&req->list, &dev->rx_reqs);
-		break;
-	}
-
-	wake_up_interruptible(&dev->rx_wait);
-	spin_unlock_irqrestore(&dev->lock, flags);
-}
-
-static void tx_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct printer_dev	*dev = ep->driver_data;
-
-	switch (req->status) {
-	default:
-		VDBG(dev, "tx err %d\n", req->status);
-		/* FALLTHROUGH */
-	case -ECONNRESET:		/* unlink */
-	case -ESHUTDOWN:		/* disconnect etc */
-		break;
-	case 0:
-		break;
-	}
-
-	spin_lock(&dev->lock);
-	/* Take the request struct off the active list and put it on the
-	 * free list.
-	 */
-	list_del_init(&req->list);
-	list_add(&req->list, &dev->tx_reqs);
-	wake_up_interruptible(&dev->tx_wait);
-	if (likely(list_empty(&dev->tx_reqs_active)))
-		wake_up_interruptible(&dev->tx_flush_wait);
-
-	spin_unlock(&dev->lock);
-}
-
-/*-------------------------------------------------------------------------*/
-
-static int
-printer_open(struct inode *inode, struct file *fd)
-{
-	struct printer_dev	*dev;
-	unsigned long		flags;
-	int			ret = -EBUSY;
-
-	mutex_lock(&printer_mutex);
-	dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
-
-	spin_lock_irqsave(&dev->lock, flags);
-
-	if (!dev->printer_cdev_open) {
-		dev->printer_cdev_open = 1;
-		fd->private_data = dev;
-		ret = 0;
-		/* Change the printer status to show that it's on-line. */
-		dev->printer_status |= PRINTER_SELECTED;
-	}
-
-	spin_unlock_irqrestore(&dev->lock, flags);
-
-	DBG(dev, "printer_open returned %x\n", ret);
-	mutex_unlock(&printer_mutex);
-	return ret;
-}
-
-static int
-printer_close(struct inode *inode, struct file *fd)
-{
-	struct printer_dev	*dev = fd->private_data;
-	unsigned long		flags;
-
-	spin_lock_irqsave(&dev->lock, flags);
-	dev->printer_cdev_open = 0;
-	fd->private_data = NULL;
-	/* Change printer status to show that the printer is off-line. */
-	dev->printer_status &= ~PRINTER_SELECTED;
-	spin_unlock_irqrestore(&dev->lock, flags);
-
-	DBG(dev, "printer_close\n");
-
-	return 0;
-}
-
-/* This function must be called with interrupts turned off. */
-static void
-setup_rx_reqs(struct printer_dev *dev)
-{
-	struct usb_request              *req;
-
-	while (likely(!list_empty(&dev->rx_reqs))) {
-		int error;
-
-		req = container_of(dev->rx_reqs.next,
-				struct usb_request, list);
-		list_del_init(&req->list);
-
-		/* The USB Host sends us whatever amount of data it wants to
-		 * so we always set the length field to the full USB_BUFSIZE.
-		 * If the amount of data is more than the read() caller asked
-		 * for it will be stored in the request buffer until it is
-		 * asked for by read().
-		 */
-		req->length = USB_BUFSIZE;
-		req->complete = rx_complete;
-
-		/* here, we unlock, and only unlock, to avoid deadlock. */
-		spin_unlock(&dev->lock);
-		error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
-		spin_lock(&dev->lock);
-		if (error) {
-			DBG(dev, "rx submit --> %d\n", error);
-			list_add(&req->list, &dev->rx_reqs);
-			break;
-		}
-		/* if the req is empty, then add it into dev->rx_reqs_active. */
-		else if (list_empty(&req->list)) {
-			list_add(&req->list, &dev->rx_reqs_active);
-		}
-	}
-}
-
-static ssize_t
-printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
-{
-	struct printer_dev		*dev = fd->private_data;
-	unsigned long			flags;
-	size_t				size;
-	size_t				bytes_copied;
-	struct usb_request		*req;
-	/* This is a pointer to the current USB rx request. */
-	struct usb_request		*current_rx_req;
-	/* This is the number of bytes in the current rx buffer. */
-	size_t				current_rx_bytes;
-	/* This is a pointer to the current rx buffer. */
-	u8				*current_rx_buf;
-
-	if (len == 0)
-		return -EINVAL;
-
-	DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
-
-	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
-	 * after we turn interrupts back on.
-	 */
-	dev->reset_printer = 0;
-
-	setup_rx_reqs(dev);
-
-	bytes_copied = 0;
-	current_rx_req = dev->current_rx_req;
-	current_rx_bytes = dev->current_rx_bytes;
-	current_rx_buf = dev->current_rx_buf;
-	dev->current_rx_req = NULL;
-	dev->current_rx_bytes = 0;
-	dev->current_rx_buf = NULL;
-
-	/* Check if there is any data in the read buffers. Please note that
-	 * current_rx_bytes is the number of bytes in the current rx buffer.
-	 * If it is zero then check if there are any other rx_buffers that
-	 * are on the completed list. We are only out of data if all rx
-	 * buffers are empty.
-	 */
-	if ((current_rx_bytes == 0) &&
-			(likely(list_empty(&dev->rx_buffers)))) {
-		/* Turn interrupts back on before sleeping. */
-		spin_unlock_irqrestore(&dev->lock, flags);
-
-		/*
-		 * If no data is available check if this is a NON-Blocking
-		 * call or not.
-		 */
-		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
-			mutex_unlock(&dev->lock_printer_io);
-			return -EAGAIN;
-		}
-
-		/* Sleep until data is available */
-		wait_event_interruptible(dev->rx_wait,
-				(likely(!list_empty(&dev->rx_buffers))));
-		spin_lock_irqsave(&dev->lock, flags);
-	}
-
-	/* We have data to return then copy it to the caller's buffer.*/
-	while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
-			&& len) {
-		if (current_rx_bytes == 0) {
-			req = container_of(dev->rx_buffers.next,
-					struct usb_request, list);
-			list_del_init(&req->list);
-
-			if (req->actual && req->buf) {
-				current_rx_req = req;
-				current_rx_bytes = req->actual;
-				current_rx_buf = req->buf;
-			} else {
-				list_add(&req->list, &dev->rx_reqs);
-				continue;
-			}
-		}
-
-		/* Don't leave irqs off while doing memory copies */
-		spin_unlock_irqrestore(&dev->lock, flags);
-
-		if (len > current_rx_bytes)
-			size = current_rx_bytes;
-		else
-			size = len;
-
-		size -= copy_to_user(buf, current_rx_buf, size);
-		bytes_copied += size;
-		len -= size;
-		buf += size;
-
-		spin_lock_irqsave(&dev->lock, flags);
-
-		/* We've disconnected or reset so return. */
-		if (dev->reset_printer) {
-			list_add(&current_rx_req->list, &dev->rx_reqs);
-			spin_unlock_irqrestore(&dev->lock, flags);
-			mutex_unlock(&dev->lock_printer_io);
-			return -EAGAIN;
-		}
-
-		/* If we not returning all the data left in this RX request
-		 * buffer then adjust the amount of data left in the buffer.
-		 * Othewise if we are done with this RX request buffer then
-		 * requeue it to get any incoming data from the USB host.
-		 */
-		if (size < current_rx_bytes) {
-			current_rx_bytes -= size;
-			current_rx_buf += size;
-		} else {
-			list_add(&current_rx_req->list, &dev->rx_reqs);
-			current_rx_bytes = 0;
-			current_rx_buf = NULL;
-			current_rx_req = NULL;
-		}
-	}
-
-	dev->current_rx_req = current_rx_req;
-	dev->current_rx_bytes = current_rx_bytes;
-	dev->current_rx_buf = current_rx_buf;
-
-	spin_unlock_irqrestore(&dev->lock, flags);
-	mutex_unlock(&dev->lock_printer_io);
-
-	DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
-
-	if (bytes_copied)
-		return bytes_copied;
-	else
-		return -EAGAIN;
-}
-
-static ssize_t
-printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
-{
-	struct printer_dev	*dev = fd->private_data;
-	unsigned long		flags;
-	size_t			size;	/* Amount of data in a TX request. */
-	size_t			bytes_copied = 0;
-	struct usb_request	*req;
-
-	DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
-
-	if (len == 0)
-		return -EINVAL;
-
-	mutex_lock(&dev->lock_printer_io);
-	spin_lock_irqsave(&dev->lock, flags);
-
-	/* Check if a printer reset happens while we have interrupts on */
-	dev->reset_printer = 0;
-
-	/* Check if there is any available write buffers */
-	if (likely(list_empty(&dev->tx_reqs))) {
-		/* Turn interrupts back on before sleeping. */
-		spin_unlock_irqrestore(&dev->lock, flags);
-
-		/*
-		 * If write buffers are available check if this is
-		 * a NON-Blocking call or not.
-		 */
-		if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
-			mutex_unlock(&dev->lock_printer_io);
-			return -EAGAIN;
-		}
-
-		/* Sleep until a write buffer is available */
-		wait_event_interruptible(dev->tx_wait,
-				(likely(!list_empty(&dev->tx_reqs))));
-		spin_lock_irqsave(&dev->lock, flags);
-	}
-
-	while (likely(!list_empty(&dev->tx_reqs)) && len) {
-
-		if (len > USB_BUFSIZE)
-			size = USB_BUFSIZE;
-		else
-			size = len;
-
-		req = container_of(dev->tx_reqs.next, struct usb_request,
-				list);
-		list_del_init(&req->list);
-
-		req->complete = tx_complete;
-		req->length = size;
-
-		/* Check if we need to send a zero length packet. */
-		if (len > size)
-			/* They will be more TX requests so no yet. */
-			req->zero = 0;
-		else
-			/* If the data amount is not a multple of the
-			 * maxpacket size then send a zero length packet.
-			 */
-			req->zero = ((len % dev->in_ep->maxpacket) == 0);
-
-		/* Don't leave irqs off while doing memory copies */
-		spin_unlock_irqrestore(&dev->lock, flags);
-
-		if (copy_from_user(req->buf, buf, size)) {
-			list_add(&req->list, &dev->tx_reqs);
-			mutex_unlock(&dev->lock_printer_io);
-			return bytes_copied;
-		}
-
-		bytes_copied += size;
-		len -= size;
-		buf += size;
-
-		spin_lock_irqsave(&dev->lock, flags);
-
-		/* We've disconnected or reset so free the req and buffer */
-		if (dev->reset_printer) {
-			list_add(&req->list, &dev->tx_reqs);
-			spin_unlock_irqrestore(&dev->lock, flags);
-			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);
-			mutex_unlock(&dev->lock_printer_io);
-			return -EAGAIN;
-		}
-
-		list_add(&req->list, &dev->tx_reqs_active);
-
-	}
-
-	spin_unlock_irqrestore(&dev->lock, flags);
-	mutex_unlock(&dev->lock_printer_io);
-
-	DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
-
-	if (bytes_copied) {
-		return bytes_copied;
-	} else {
-		return -EAGAIN;
-	}
-}
-
-static int
-printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
-{
-	struct printer_dev	*dev = fd->private_data;
-	struct inode *inode = file_inode(fd);
-	unsigned long		flags;
-	int			tx_list_empty;
-
-	mutex_lock(&inode->i_mutex);
-	spin_lock_irqsave(&dev->lock, flags);
-	tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
-	spin_unlock_irqrestore(&dev->lock, flags);
-
-	if (!tx_list_empty) {
-		/* Sleep until all data has been sent */
-		wait_event_interruptible(dev->tx_flush_wait,
-				(likely(list_empty(&dev->tx_reqs_active))));
-	}
-	mutex_unlock(&inode->i_mutex);
-
-	return 0;
-}
-
-static unsigned int
-printer_poll(struct file *fd, poll_table *wait)
-{
-	struct printer_dev	*dev = fd->private_data;
-	unsigned long		flags;
-	int			status = 0;
-
-	mutex_lock(&dev->lock_printer_io);
-	spin_lock_irqsave(&dev->lock, flags);
-	setup_rx_reqs(dev);
-	spin_unlock_irqrestore(&dev->lock, flags);
-	mutex_unlock(&dev->lock_printer_io);
-
-	poll_wait(fd, &dev->rx_wait, wait);
-	poll_wait(fd, &dev->tx_wait, wait);
-
-	spin_lock_irqsave(&dev->lock, flags);
-	if (likely(!list_empty(&dev->tx_reqs)))
-		status |= POLLOUT | POLLWRNORM;
-
-	if (likely(dev->current_rx_bytes) ||
-			likely(!list_empty(&dev->rx_buffers)))
-		status |= POLLIN | POLLRDNORM;
-
-	spin_unlock_irqrestore(&dev->lock, flags);
-
-	return status;
-}
-
-static long
-printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
-{
-	struct printer_dev	*dev = fd->private_data;
-	unsigned long		flags;
-	int			status = 0;
-
-	DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
-
-	/* handle ioctls */
-
-	spin_lock_irqsave(&dev->lock, flags);
-
-	switch (code) {
-	case GADGET_GET_PRINTER_STATUS:
-		status = (int)dev->printer_status;
-		break;
-	case GADGET_SET_PRINTER_STATUS:
-		dev->printer_status = (u8)arg;
-		break;
-	default:
-		/* could not handle ioctl */
-		DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
-				code);
-		status = -ENOTTY;
-	}
-
-	spin_unlock_irqrestore(&dev->lock, flags);
-
-	return status;
-}
-
-/* used after endpoint configuration */
-static const struct file_operations printer_io_operations = {
-	.owner =	THIS_MODULE,
-	.open =		printer_open,
-	.read =		printer_read,
-	.write =	printer_write,
-	.fsync =	printer_fsync,
-	.poll =		printer_poll,
-	.unlocked_ioctl = printer_ioctl,
-	.release =	printer_close,
-	.llseek =	noop_llseek,
-};
-
-/*-------------------------------------------------------------------------*/
-
-static int
-set_printer_interface(struct printer_dev *dev)
-{
-	int			result = 0;
-
-	dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
-				&ss_ep_in_desc);
-	dev->in_ep->driver_data = dev;
-
-	dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
-				    &hs_ep_out_desc, &ss_ep_out_desc);
-	dev->out_ep->driver_data = dev;
-
-	result = usb_ep_enable(dev->in_ep);
-	if (result != 0) {
-		DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
-		goto done;
-	}
-
-	result = usb_ep_enable(dev->out_ep);
-	if (result != 0) {
-		DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
-		goto done;
-	}
-
-done:
-	/* on error, disable any endpoints  */
-	if (result != 0) {
-		(void) usb_ep_disable(dev->in_ep);
-		(void) usb_ep_disable(dev->out_ep);
-		dev->in_ep->desc = NULL;
-		dev->out_ep->desc = NULL;
-	}
-
-	/* caller is responsible for cleanup on error */
-	return result;
-}
-
-static void printer_reset_interface(struct printer_dev *dev)
-{
-	if (dev->interface < 0)
-		return;
-
-	DBG(dev, "%s\n", __func__);
-
-	if (dev->in_ep->desc)
-		usb_ep_disable(dev->in_ep);
-
-	if (dev->out_ep->desc)
-		usb_ep_disable(dev->out_ep);
-
-	dev->in_ep->desc = NULL;
-	dev->out_ep->desc = NULL;
-	dev->interface = -1;
-}
-
-/* Change our operational Interface. */
-static int set_interface(struct printer_dev *dev, unsigned number)
-{
-	int			result = 0;
-
-	/* Free the current interface */
-	printer_reset_interface(dev);
-
-	result = set_printer_interface(dev);
-	if (result)
-		printer_reset_interface(dev);
-	else
-		dev->interface = number;
-
-	if (!result)
-		INFO(dev, "Using interface %x\n", number);
-
-	return result;
-}
-
-static void printer_soft_reset(struct printer_dev *dev)
-{
-	struct usb_request	*req;
-
-	INFO(dev, "Received Printer Reset Request\n");
-
-	if (usb_ep_disable(dev->in_ep))
-		DBG(dev, "Failed to disable USB in_ep\n");
-	if (usb_ep_disable(dev->out_ep))
-		DBG(dev, "Failed to disable USB out_ep\n");
-
-	if (dev->current_rx_req != NULL) {
-		list_add(&dev->current_rx_req->list, &dev->rx_reqs);
-		dev->current_rx_req = NULL;
-	}
-	dev->current_rx_bytes = 0;
-	dev->current_rx_buf = NULL;
-	dev->reset_printer = 1;
-
-	while (likely(!(list_empty(&dev->rx_buffers)))) {
-		req = container_of(dev->rx_buffers.next, struct usb_request,
-				list);
-		list_del_init(&req->list);
-		list_add(&req->list, &dev->rx_reqs);
-	}
-
-	while (likely(!(list_empty(&dev->rx_reqs_active)))) {
-		req = container_of(dev->rx_buffers.next, struct usb_request,
-				list);
-		list_del_init(&req->list);
-		list_add(&req->list, &dev->rx_reqs);
-	}
-
-	while (likely(!(list_empty(&dev->tx_reqs_active)))) {
-		req = container_of(dev->tx_reqs_active.next,
-				struct usb_request, list);
-		list_del_init(&req->list);
-		list_add(&req->list, &dev->tx_reqs);
-	}
-
-	if (usb_ep_enable(dev->in_ep))
-		DBG(dev, "Failed to enable USB in_ep\n");
-	if (usb_ep_enable(dev->out_ep))
-		DBG(dev, "Failed to enable USB out_ep\n");
-
-	wake_up_interruptible(&dev->rx_wait);
-	wake_up_interruptible(&dev->tx_wait);
-	wake_up_interruptible(&dev->tx_flush_wait);
-}
-
-/*-------------------------------------------------------------------------*/
-
-/*
- * The setup() callback implements all the ep0 functionality that's not
- * handled lower down.
- */
-static int printer_func_setup(struct usb_function *f,
-		const struct usb_ctrlrequest *ctrl)
-{
-	struct printer_dev *dev = container_of(f, struct printer_dev, function);
-	struct usb_composite_dev *cdev = f->config->cdev;
-	struct usb_request	*req = cdev->req;
-	int			value = -EOPNOTSUPP;
-	u16			wIndex = le16_to_cpu(ctrl->wIndex);
-	u16			wValue = le16_to_cpu(ctrl->wValue);
-	u16			wLength = le16_to_cpu(ctrl->wLength);
-
-	DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
-		ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
-
-	switch (ctrl->bRequestType&USB_TYPE_MASK) {
-	case USB_TYPE_CLASS:
-		switch (ctrl->bRequest) {
-		case 0: /* Get the IEEE-1284 PNP String */
-			/* Only one printer interface is supported. */
-			if ((wIndex>>8) != dev->interface)
-				break;
-
-			value = (pnp_string[0]<<8)|pnp_string[1];
-			memcpy(req->buf, pnp_string, value);
-			DBG(dev, "1284 PNP String: %x %s\n", value,
-					&pnp_string[2]);
-			break;
-
-		case 1: /* Get Port Status */
-			/* Only one printer interface is supported. */
-			if (wIndex != dev->interface)
-				break;
-
-			*(u8 *)req->buf = dev->printer_status;
-			value = min(wLength, (u16) 1);
-			break;
-
-		case 2: /* Soft Reset */
-			/* Only one printer interface is supported. */
-			if (wIndex != dev->interface)
-				break;
-
-			printer_soft_reset(dev);
-
-			value = 0;
-			break;
-
-		default:
-			goto unknown;
-		}
-		break;
-
-	default:
-unknown:
-		VDBG(dev,
-			"unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
-			ctrl->bRequestType, ctrl->bRequest,
-			wValue, wIndex, wLength);
-		break;
-	}
-	/* host either stalls (value < 0) or reports success */
-	return value;
-}
-
-static int __init printer_func_bind(struct usb_configuration *c,
-		struct usb_function *f)
-{
-	struct printer_dev *dev = container_of(f, struct printer_dev, function);
-	struct usb_composite_dev *cdev = c->cdev;
-	struct usb_ep *in_ep;
-	struct usb_ep *out_ep = NULL;
-	int id;
-	int ret;
-
-	id = usb_interface_id(c, f);
-	if (id < 0)
-		return id;
-	intf_desc.bInterfaceNumber = id;
-
-	/* all we really need is bulk IN/OUT */
-	in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
-	if (!in_ep) {
-autoconf_fail:
-		dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
-			cdev->gadget->name);
-		return -ENODEV;
-	}
-	in_ep->driver_data = in_ep;	/* claim */
-
-	out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
-	if (!out_ep)
-		goto autoconf_fail;
-	out_ep->driver_data = out_ep;	/* claim */
-
-	/* assumes that all endpoints are dual-speed */
-	hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
-	hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
-	ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
-	ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
-
-	ret = usb_assign_descriptors(f, fs_printer_function,
-			hs_printer_function, ss_printer_function);
-	if (ret)
-		return ret;
-
-	dev->in_ep = in_ep;
-	dev->out_ep = out_ep;
-	return 0;
-}
-
-static void printer_func_unbind(struct usb_configuration *c,
-		struct usb_function *f)
-{
-	usb_free_all_descriptors(f);
-}
-
-static int printer_func_set_alt(struct usb_function *f,
-		unsigned intf, unsigned alt)
-{
-	struct printer_dev *dev = container_of(f, struct printer_dev, function);
-	int ret = -ENOTSUPP;
-
-	if (!alt)
-		ret = set_interface(dev, intf);
-
-	return ret;
-}
-
-static void printer_func_disable(struct usb_function *f)
-{
-	struct printer_dev *dev = container_of(f, struct printer_dev, function);
-	unsigned long		flags;
-
-	DBG(dev, "%s\n", __func__);
-
-	spin_lock_irqsave(&dev->lock, flags);
-	printer_reset_interface(dev);
-	spin_unlock_irqrestore(&dev->lock, flags);
-}
-
-static void printer_cfg_unbind(struct usb_configuration *c)
-{
-	struct printer_dev	*dev;
-	struct usb_request	*req;
-
-	dev = &usb_printer_gadget;
-
-	DBG(dev, "%s\n", __func__);
-
-	/* Remove sysfs files */
-	device_destroy(usb_gadget_class, g_printer_devno);
-
-	/* Remove Character Device */
-	cdev_del(&dev->printer_cdev);
-
-	/* we must already have been disconnected ... no i/o may be active */
-	WARN_ON(!list_empty(&dev->tx_reqs_active));
-	WARN_ON(!list_empty(&dev->rx_reqs_active));
-
-	/* Free all memory for this driver. */
-	while (!list_empty(&dev->tx_reqs)) {
-		req = container_of(dev->tx_reqs.next, struct usb_request,
-				list);
-		list_del(&req->list);
-		printer_req_free(dev->in_ep, req);
-	}
-
-	if (dev->current_rx_req != NULL)
-		printer_req_free(dev->out_ep, dev->current_rx_req);
-
-	while (!list_empty(&dev->rx_reqs)) {
-		req = container_of(dev->rx_reqs.next,
-				struct usb_request, list);
-		list_del(&req->list);
-		printer_req_free(dev->out_ep, req);
-	}
-
-	while (!list_empty(&dev->rx_buffers)) {
-		req = container_of(dev->rx_buffers.next,
-				struct usb_request, list);
-		list_del(&req->list);
-		printer_req_free(dev->out_ep, req);
-	}
-}
-
 static struct usb_configuration printer_cfg_driver = {
 	.label			= "printer",
-	.unbind			= printer_cfg_unbind,
 	.bConfigurationValue	= 1,
 	.bmAttributes		= USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 };
 
-static int __init printer_bind_config(struct usb_configuration *c)
+static int __init printer_do_config(struct usb_configuration *c)
 {
 	struct usb_gadget	*gadget = c->cdev->gadget;
-	struct printer_dev	*dev;
-	int			status = -ENOMEM;
-	size_t			len;
-	u32			i;
-	struct usb_request	*req;
+	int			status = 0;
 
 	usb_ep_autoconfig_reset(gadget);
 
-	dev = &usb_printer_gadget;
-
-	dev->function.name = shortname;
-	dev->function.bind = printer_func_bind;
-	dev->function.setup = printer_func_setup;
-	dev->function.unbind = printer_func_unbind;
-	dev->function.set_alt = printer_func_set_alt;
-	dev->function.disable = printer_func_disable;
-
-	status = usb_add_function(c, &dev->function);
-	if (status)
-		return status;
-
-	/* Setup the sysfs files for the printer gadget. */
-	dev->pdev = device_create(usb_gadget_class, NULL, g_printer_devno,
-				  NULL, "g_printer");
-	if (IS_ERR(dev->pdev)) {
-		ERROR(dev, "Failed to create device: g_printer\n");
-		status = PTR_ERR(dev->pdev);
-		goto fail;
-	}
-
-	/*
-	 * Register a character device as an interface to a user mode
-	 * program that handles the printer specific functionality.
-	 */
-	cdev_init(&dev->printer_cdev, &printer_io_operations);
-	dev->printer_cdev.owner = THIS_MODULE;
-	status = cdev_add(&dev->printer_cdev, g_printer_devno, 1);
-	if (status) {
-		ERROR(dev, "Failed to open char device\n");
-		goto fail;
-	}
-
-	if (iPNPstring)
-		strlcpy(&pnp_string[2], iPNPstring, (sizeof pnp_string)-2);
-
-	len = strlen(pnp_string);
-	pnp_string[0] = (len >> 8) & 0xFF;
-	pnp_string[1] = len & 0xFF;
-
 	usb_gadget_set_selfpowered(gadget);
 
 	if (gadget_is_otg(gadget)) {
@@ -1222,86 +141,64 @@ static int __init printer_bind_config(struct usb_configuration *c)
 		printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 	}
 
-	spin_lock_init(&dev->lock);
-	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);
-	INIT_LIST_HEAD(&dev->rx_reqs_active);
-	INIT_LIST_HEAD(&dev->rx_buffers);
-	init_waitqueue_head(&dev->rx_wait);
-	init_waitqueue_head(&dev->tx_wait);
-	init_waitqueue_head(&dev->tx_flush_wait);
-
-	dev->interface = -1;
-	dev->printer_cdev_open = 0;
-	dev->printer_status = PRINTER_NOT_ERROR;
-	dev->current_rx_req = NULL;
-	dev->current_rx_bytes = 0;
-	dev->current_rx_buf = NULL;
-
-	for (i = 0; i < QLEN; i++) {
-		req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
-		if (!req) {
-			while (!list_empty(&dev->tx_reqs)) {
-				req = container_of(dev->tx_reqs.next,
-						struct usb_request, list);
-				list_del(&req->list);
-				printer_req_free(dev->in_ep, req);
-			}
-			return -ENOMEM;
-		}
-		list_add(&req->list, &dev->tx_reqs);
-	}
-
-	for (i = 0; i < QLEN; i++) {
-		req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
-		if (!req) {
-			while (!list_empty(&dev->rx_reqs)) {
-				req = container_of(dev->rx_reqs.next,
-						struct usb_request, list);
-				list_del(&req->list);
-				printer_req_free(dev->out_ep, req);
-			}
-			return -ENOMEM;
-		}
-		list_add(&req->list, &dev->rx_reqs);
-	}
-
-	/* finish hookup to lower layer ... */
-	dev->gadget = gadget;
+	f_printer = usb_get_function(fi_printer);
+	if (IS_ERR(f_printer))
+		return PTR_ERR(f_printer);
 
-	INFO(dev, "%s, version: " DRIVER_VERSION "\n", driver_desc);
-	return 0;
+	status = usb_add_function(c, f_printer);
+	if (status < 0)
+		usb_put_function(f_printer);
 
-fail:
-	printer_cfg_unbind(c);
 	return status;
 }
 
-static int printer_unbind(struct usb_composite_dev *cdev)
-{
-	return 0;
-}
-
 static int __init printer_bind(struct usb_composite_dev *cdev)
 {
-	int ret;
+	struct f_printer_opts *opts;
+	int ret, len;
+
+	fi_printer = usb_get_function_instance("printer");
+	if (IS_ERR(fi_printer))
+		return PTR_ERR(fi_printer);
+
+	if (iPNPstring)
+		strlcpy(&pnp_string[2], iPNPstring, PNP_STRING_LEN - 2);
+
+	len = strlen(pnp_string);
+	pnp_string[0] = (len >> 8) & 0xFF;
+	pnp_string[1] = len & 0xFF;
+
+	opts = container_of(fi_printer, struct f_printer_opts, func_inst);
+	opts->minor = 0;
+	memcpy(opts->pnp_string, pnp_string, PNP_STRING_LEN);
+	opts->q_len = QLEN;
 
 	ret = usb_string_ids_tab(cdev, strings);
-	if (ret < 0)
+	if (ret < 0) {
+		usb_put_function_instance(fi_printer);
 		return ret;
+	}
 	device_desc.iManufacturer = strings[USB_GADGET_MANUFACTURER_IDX].id;
 	device_desc.iProduct = strings[USB_GADGET_PRODUCT_IDX].id;
 	device_desc.iSerialNumber = strings[USB_GADGET_SERIAL_IDX].id;
 
-	ret = usb_add_config(cdev, &printer_cfg_driver, printer_bind_config);
-	if (ret)
+	ret = usb_add_config(cdev, &printer_cfg_driver, printer_do_config);
+	if (ret) {
+		usb_put_function_instance(fi_printer);
 		return ret;
+	}
 	usb_composite_overwrite_options(cdev, &coverwrite);
 	return ret;
 }
 
+static int __exit printer_unbind(struct usb_composite_dev *cdev)
+{
+	usb_put_function(f_printer);
+	usb_put_function_instance(fi_printer);
+
+	return 0;
+}
+
 static __refdata struct usb_composite_driver printer_driver = {
 	.name           = shortname,
 	.dev            = &device_desc,
@@ -1311,47 +208,7 @@ static __refdata struct usb_composite_driver printer_driver = {
 	.unbind		= printer_unbind,
 };
 
-static int __init
-init(void)
-{
-	int status;
-
-	usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
-	if (IS_ERR(usb_gadget_class)) {
-		status = PTR_ERR(usb_gadget_class);
-		pr_err("unable to create usb_gadget class %d\n", status);
-		return status;
-	}
-
-	status = alloc_chrdev_region(&g_printer_devno, 0, 1,
-			"USB printer gadget");
-	if (status) {
-		pr_err("alloc_chrdev_region %d\n", status);
-		class_destroy(usb_gadget_class);
-		return status;
-	}
-
-	status = usb_composite_probe(&printer_driver);
-	if (status) {
-		class_destroy(usb_gadget_class);
-		unregister_chrdev_region(g_printer_devno, 1);
-		pr_err("usb_gadget_probe_driver %x\n", status);
-	}
-
-	return status;
-}
-module_init(init);
-
-static void __exit
-cleanup(void)
-{
-	mutex_lock(&usb_printer_gadget.lock_printer_io);
-	usb_composite_unregister(&printer_driver);
-	unregister_chrdev_region(g_printer_devno, 1);
-	class_destroy(usb_gadget_class);
-	mutex_unlock(&usb_printer_gadget.lock_printer_io);
-}
-module_exit(cleanup);
+module_usb_composite_driver(printer_driver);
 
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_AUTHOR("Craig Nadler");
diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index d79cb35dbf8a..4c01953a0869 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -152,7 +152,7 @@ static int regs_dbg_open(struct inode *inode, struct file *file)
 
 	spin_lock_irq(&udc->lock);
 	for (i = 0; i < inode->i_size / 4; i++)
-		data[i] = __raw_readl(udc->regs + i * 4);
+		data[i] = usba_io_readl(udc->regs + i * 4);
 	spin_unlock_irq(&udc->lock);
 
 	file->private_data = data;
@@ -1249,7 +1249,7 @@ static int handle_ep0_setup(struct usba_udc *udc, struct usba_ep *ep,
 		if (crq->wLength != cpu_to_le16(sizeof(status)))
 			goto stall;
 		ep->state = DATA_STAGE_IN;
-		__raw_writew(status, ep->fifo);
+		usba_io_writew(status, ep->fifo);
 		usba_ep_writel(ep, SET_STA, USBA_TX_PK_RDY);
 		break;
 	}
@@ -1739,7 +1739,72 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
 	return IRQ_HANDLED;
 }
 
-static irqreturn_t usba_vbus_irq(int irq, void *devid)
+static int start_clock(struct usba_udc *udc)
+{
+	int ret;
+
+	if (udc->clocked)
+		return 0;
+
+	ret = clk_prepare_enable(udc->pclk);
+	if (ret)
+		return ret;
+	ret = clk_prepare_enable(udc->hclk);
+	if (ret) {
+		clk_disable_unprepare(udc->pclk);
+		return ret;
+	}
+
+	udc->clocked = true;
+	return 0;
+}
+
+static void stop_clock(struct usba_udc *udc)
+{
+	if (!udc->clocked)
+		return;
+
+	clk_disable_unprepare(udc->hclk);
+	clk_disable_unprepare(udc->pclk);
+
+	udc->clocked = false;
+}
+
+static int usba_start(struct usba_udc *udc)
+{
+	unsigned long flags;
+	int ret;
+
+	ret = start_clock(udc);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	toggle_bias(udc, 1);
+	usba_writel(udc, CTRL, USBA_ENABLE_MASK);
+	usba_int_enb_set(udc, USBA_END_OF_RESET);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static void usba_stop(struct usba_udc *udc)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	reset_all_endpoints(udc);
+
+	/* This will also disable the DP pullup */
+	toggle_bias(udc, 0);
+	usba_writel(udc, CTRL, USBA_DISABLE_MASK);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	stop_clock(udc);
+}
+
+static irqreturn_t usba_vbus_irq_thread(int irq, void *devid)
 {
 	struct usba_udc *udc = devid;
 	int vbus;
@@ -1747,35 +1812,22 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
 	/* debounce */
 	udelay(10);
 
-	spin_lock(&udc->lock);
-
-	/* May happen if Vbus pin toggles during probe() */
-	if (!udc->driver)
-		goto out;
+	mutex_lock(&udc->vbus_mutex);
 
 	vbus = vbus_is_present(udc);
 	if (vbus != udc->vbus_prev) {
 		if (vbus) {
-			toggle_bias(udc, 1);
-			usba_writel(udc, CTRL, USBA_ENABLE_MASK);
-			usba_int_enb_set(udc, USBA_END_OF_RESET);
+			usba_start(udc);
 		} else {
-			udc->gadget.speed = USB_SPEED_UNKNOWN;
-			reset_all_endpoints(udc);
-			toggle_bias(udc, 0);
-			usba_writel(udc, CTRL, USBA_DISABLE_MASK);
-			if (udc->driver->disconnect) {
-				spin_unlock(&udc->lock);
+			usba_stop(udc);
+
+			if (udc->driver->disconnect)
 				udc->driver->disconnect(&udc->gadget);
-				spin_lock(&udc->lock);
-			}
 		}
 		udc->vbus_prev = vbus;
 	}
 
-out:
-	spin_unlock(&udc->lock);
-
+	mutex_unlock(&udc->vbus_mutex);
 	return IRQ_HANDLED;
 }
 
@@ -1787,55 +1839,47 @@ static int atmel_usba_start(struct usb_gadget *gadget,
 	unsigned long flags;
 
 	spin_lock_irqsave(&udc->lock, flags);
-
 	udc->devstatus = 1 << USB_DEVICE_SELF_POWERED;
 	udc->driver = driver;
 	spin_unlock_irqrestore(&udc->lock, flags);
 
-	ret = clk_prepare_enable(udc->pclk);
-	if (ret)
-		return ret;
-	ret = clk_prepare_enable(udc->hclk);
-	if (ret) {
-		clk_disable_unprepare(udc->pclk);
-		return ret;
-	}
+	mutex_lock(&udc->vbus_mutex);
 
-	udc->vbus_prev = 0;
 	if (gpio_is_valid(udc->vbus_pin))
 		enable_irq(gpio_to_irq(udc->vbus_pin));
 
 	/* If Vbus is present, enable the controller and wait for reset */
-	spin_lock_irqsave(&udc->lock, flags);
-	if (vbus_is_present(udc) && udc->vbus_prev == 0) {
-		toggle_bias(udc, 1);
-		usba_writel(udc, CTRL, USBA_ENABLE_MASK);
-		usba_int_enb_set(udc, USBA_END_OF_RESET);
+	udc->vbus_prev = vbus_is_present(udc);
+	if (udc->vbus_prev) {
+		ret = usba_start(udc);
+		if (ret)
+			goto err;
 	}
-	spin_unlock_irqrestore(&udc->lock, flags);
 
+	mutex_unlock(&udc->vbus_mutex);
 	return 0;
+
+err:
+	if (gpio_is_valid(udc->vbus_pin))
+		disable_irq(gpio_to_irq(udc->vbus_pin));
+
+	mutex_unlock(&udc->vbus_mutex);
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
+	udc->driver = NULL;
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return ret;
 }
 
 static int atmel_usba_stop(struct usb_gadget *gadget)
 {
 	struct usba_udc *udc = container_of(gadget, struct usba_udc, gadget);
-	unsigned long flags;
 
 	if (gpio_is_valid(udc->vbus_pin))
 		disable_irq(gpio_to_irq(udc->vbus_pin));
 
-	spin_lock_irqsave(&udc->lock, flags);
-	udc->gadget.speed = USB_SPEED_UNKNOWN;
-	reset_all_endpoints(udc);
-	spin_unlock_irqrestore(&udc->lock, flags);
-
-	/* This will also disable the DP pullup */
-	toggle_bias(udc, 0);
-	usba_writel(udc, CTRL, USBA_DISABLE_MASK);
-
-	clk_disable_unprepare(udc->hclk);
-	clk_disable_unprepare(udc->pclk);
+	usba_stop(udc);
 
 	udc->driver = NULL;
 
@@ -2057,6 +2101,7 @@ static int usba_udc_probe(struct platform_device *pdev)
 		return PTR_ERR(hclk);
 
 	spin_lock_init(&udc->lock);
+	mutex_init(&udc->vbus_mutex);
 	udc->pdev = pdev;
 	udc->pclk = pclk;
 	udc->hclk = hclk;
@@ -2111,17 +2156,17 @@ static int usba_udc_probe(struct platform_device *pdev)
 
 	if (gpio_is_valid(udc->vbus_pin)) {
 		if (!devm_gpio_request(&pdev->dev, udc->vbus_pin, "atmel_usba_udc")) {
-			ret = devm_request_irq(&pdev->dev,
-					gpio_to_irq(udc->vbus_pin),
-					usba_vbus_irq, 0,
+			irq_set_status_flags(gpio_to_irq(udc->vbus_pin),
+					IRQ_NOAUTOEN);
+			ret = devm_request_threaded_irq(&pdev->dev,
+					gpio_to_irq(udc->vbus_pin), NULL,
+					usba_vbus_irq_thread, IRQF_ONESHOT,
 					"atmel_usba_udc", udc);
 			if (ret) {
 				udc->vbus_pin = -ENODEV;
 				dev_warn(&udc->pdev->dev,
 					 "failed to request vbus irq; "
 					 "assuming always on\n");
-			} else {
-				disable_irq(gpio_to_irq(udc->vbus_pin));
 			}
 		} else {
 			/* gpio_request fail so use -EINVAL for gpio_is_valid */
@@ -2132,6 +2177,7 @@ static int usba_udc_probe(struct platform_device *pdev)
 	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
 	if (ret)
 		return ret;
+	device_init_wakeup(&pdev->dev, 1);
 
 	usba_init_debugfs(udc);
 	for (i = 1; i < udc->num_ep; i++)
@@ -2147,6 +2193,7 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
 
 	udc = platform_get_drvdata(pdev);
 
+	device_init_wakeup(&pdev->dev, 0);
 	usb_del_gadget_udc(&udc->gadget);
 
 	for (i = 1; i < udc->num_ep; i++)
@@ -2156,10 +2203,65 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int usba_udc_suspend(struct device *dev)
+{
+	struct usba_udc *udc = dev_get_drvdata(dev);
+
+	/* Not started */
+	if (!udc->driver)
+		return 0;
+
+	mutex_lock(&udc->vbus_mutex);
+
+	if (!device_may_wakeup(dev)) {
+		usba_stop(udc);
+		goto out;
+	}
+
+	/*
+	 * Device may wake up. We stay clocked if we failed
+	 * to request vbus irq, assuming always on.
+	 */
+	if (gpio_is_valid(udc->vbus_pin)) {
+		usba_stop(udc);
+		enable_irq_wake(gpio_to_irq(udc->vbus_pin));
+	}
+
+out:
+	mutex_unlock(&udc->vbus_mutex);
+	return 0;
+}
+
+static int usba_udc_resume(struct device *dev)
+{
+	struct usba_udc *udc = dev_get_drvdata(dev);
+
+	/* Not started */
+	if (!udc->driver)
+		return 0;
+
+	if (device_may_wakeup(dev) && gpio_is_valid(udc->vbus_pin))
+		disable_irq_wake(gpio_to_irq(udc->vbus_pin));
+
+	/* If Vbus is present, enable the controller and wait for reset */
+	mutex_lock(&udc->vbus_mutex);
+	udc->vbus_prev = vbus_is_present(udc);
+	if (udc->vbus_prev)
+		usba_start(udc);
+	mutex_unlock(&udc->vbus_mutex);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(usba_udc_pm_ops, usba_udc_suspend, usba_udc_resume);
+
 static struct platform_driver udc_driver = {
 	.remove		= __exit_p(usba_udc_remove),
 	.driver		= {
 		.name		= "atmel_usba_udc",
+		.pm		= &usba_udc_pm_ops,
 		.of_match_table	= of_match_ptr(atmel_udc_dt_ids),
 	},
 };
diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.h b/drivers/usb/gadget/udc/atmel_usba_udc.h
index 497cd18836f3..ea448a344767 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.h
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.h
@@ -191,18 +191,28 @@
 	 | USBA_BF(name, value))
 
 /* Register access macros */
+#ifdef CONFIG_AVR32
+#define usba_io_readl	__raw_readl
+#define usba_io_writel	__raw_writel
+#define usba_io_writew	__raw_writew
+#else
+#define usba_io_readl	readl_relaxed
+#define usba_io_writel	writel_relaxed
+#define usba_io_writew	writew_relaxed
+#endif
+
 #define usba_readl(udc, reg)					\
-	__raw_readl((udc)->regs + USBA_##reg)
+	usba_io_readl((udc)->regs + USBA_##reg)
 #define usba_writel(udc, reg, value)				\
-	__raw_writel((value), (udc)->regs + USBA_##reg)
+	usba_io_writel((value), (udc)->regs + USBA_##reg)
 #define usba_ep_readl(ep, reg)					\
-	__raw_readl((ep)->ep_regs + USBA_EPT_##reg)
+	usba_io_readl((ep)->ep_regs + USBA_EPT_##reg)
 #define usba_ep_writel(ep, reg, value)				\
-	__raw_writel((value), (ep)->ep_regs + USBA_EPT_##reg)
+	usba_io_writel((value), (ep)->ep_regs + USBA_EPT_##reg)
 #define usba_dma_readl(ep, reg)					\
-	__raw_readl((ep)->dma_regs + USBA_DMA_##reg)
+	usba_io_readl((ep)->dma_regs + USBA_DMA_##reg)
 #define usba_dma_writel(ep, reg, value)				\
-	__raw_writel((value), (ep)->dma_regs + USBA_DMA_##reg)
+	usba_io_writel((value), (ep)->dma_regs + USBA_DMA_##reg)
 
 /* Calculate base address for a given endpoint or DMA controller */
 #define USBA_EPT_BASE(x)	(0x100 + (x) * 0x20)
@@ -313,6 +323,9 @@ struct usba_udc {
 	/* Protect hw registers from concurrent modifications */
 	spinlock_t lock;
 
+	/* Mutex to prevent concurrent start or stop */
+	struct mutex vbus_mutex;
+
 	void __iomem *regs;
 	void __iomem *fifo;
 
@@ -328,6 +341,7 @@ struct usba_udc {
 	struct clk *hclk;
 	struct usba_ep *usba_ep;
 	bool bias_pulse_needed;
+	bool clocked;
 
 	u16 devstatus;
 
diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c
index 8dda48445f6f..7592db7824c6 100644
--- a/drivers/usb/gadget/udc/dummy_hcd.c
+++ b/drivers/usb/gadget/udc/dummy_hcd.c
@@ -2631,7 +2631,7 @@ static int __init init(void)
 		return -EINVAL;
 
 	if (mod_data.num < 1 || mod_data.num > MAX_NUM_UDC) {
-		pr_err("Number of emulated UDC must be in range of 1…%d\n",
+		pr_err("Number of emulated UDC must be in range of 1...%d\n",
 				MAX_NUM_UDC);
 		return -EINVAL;
 	}
diff --git a/drivers/usb/gadget/udc/goku_udc.c b/drivers/usb/gadget/udc/goku_udc.c
index 5b9176e7202a..9e8d842e8c08 100644
--- a/drivers/usb/gadget/udc/goku_udc.c
+++ b/drivers/usb/gadget/udc/goku_udc.c
@@ -1024,35 +1024,79 @@ static const char proc_node_name [] = "driver/udc";
 static void dump_intmask(struct seq_file *m, const char *label, u32 mask)
 {
 	/* int_status is the same format ... */
-	seq_printf(m,
-		"%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
-		label, mask,
-		(mask & INT_PWRDETECT) ? " power" : "",
-		(mask & INT_SYSERROR) ? " sys" : "",
-		(mask & INT_MSTRDEND) ? " in-dma" : "",
-		(mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
-
-		(mask & INT_MSTWREND) ? " out-dma" : "",
-		(mask & INT_MSTWRSET) ? " wrset" : "",
-		(mask & INT_ERR) ? " err" : "",
-		(mask & INT_SOF) ? " sof" : "",
-
-		(mask & INT_EP3NAK) ? " ep3nak" : "",
-		(mask & INT_EP2NAK) ? " ep2nak" : "",
-		(mask & INT_EP1NAK) ? " ep1nak" : "",
-		(mask & INT_EP3DATASET) ? " ep3" : "",
-
-		(mask & INT_EP2DATASET) ? " ep2" : "",
-		(mask & INT_EP1DATASET) ? " ep1" : "",
-		(mask & INT_STATUSNAK) ? " ep0snak" : "",
-		(mask & INT_STATUS) ? " ep0status" : "",
-
-		(mask & INT_SETUP) ? " setup" : "",
-		(mask & INT_ENDPOINT0) ? " ep0" : "",
-		(mask & INT_USBRESET) ? " reset" : "",
-		(mask & INT_SUSPEND) ? " suspend" : "");
+	seq_printf(m, "%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
+		   label, mask,
+		   (mask & INT_PWRDETECT) ? " power" : "",
+		   (mask & INT_SYSERROR) ? " sys" : "",
+		   (mask & INT_MSTRDEND) ? " in-dma" : "",
+		   (mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
+
+		   (mask & INT_MSTWREND) ? " out-dma" : "",
+		   (mask & INT_MSTWRSET) ? " wrset" : "",
+		   (mask & INT_ERR) ? " err" : "",
+		   (mask & INT_SOF) ? " sof" : "",
+
+		   (mask & INT_EP3NAK) ? " ep3nak" : "",
+		   (mask & INT_EP2NAK) ? " ep2nak" : "",
+		   (mask & INT_EP1NAK) ? " ep1nak" : "",
+		   (mask & INT_EP3DATASET) ? " ep3" : "",
+
+		   (mask & INT_EP2DATASET) ? " ep2" : "",
+		   (mask & INT_EP1DATASET) ? " ep1" : "",
+		   (mask & INT_STATUSNAK) ? " ep0snak" : "",
+		   (mask & INT_STATUS) ? " ep0status" : "",
+
+		   (mask & INT_SETUP) ? " setup" : "",
+		   (mask & INT_ENDPOINT0) ? " ep0" : "",
+		   (mask & INT_USBRESET) ? " reset" : "",
+		   (mask & INT_SUSPEND) ? " suspend" : "");
+}
+
+static const char *udc_ep_state(enum ep0state state)
+{
+	switch (state) {
+	case EP0_DISCONNECT:
+		return "ep0_disconnect";
+	case EP0_IDLE:
+		return "ep0_idle";
+	case EP0_IN:
+		return "ep0_in";
+	case EP0_OUT:
+		return "ep0_out";
+	case EP0_STATUS:
+		return "ep0_status";
+	case EP0_STALL:
+		return "ep0_stall";
+	case EP0_SUSPEND:
+		return "ep0_suspend";
+	}
+
+	return "ep0_?";
 }
 
+static const char *udc_ep_status(u32 status)
+{
+	switch (status & EPxSTATUS_EP_MASK) {
+	case EPxSTATUS_EP_READY:
+		return "ready";
+	case EPxSTATUS_EP_DATAIN:
+		return "packet";
+	case EPxSTATUS_EP_FULL:
+		return "full";
+	case EPxSTATUS_EP_TX_ERR:	/* host will retry */
+		return "tx_err";
+	case EPxSTATUS_EP_RX_ERR:
+		return "rx_err";
+	case EPxSTATUS_EP_BUSY:		/* ep0 only */
+		return "busy";
+	case EPxSTATUS_EP_STALL:
+		return "stall";
+	case EPxSTATUS_EP_INVALID:	/* these "can't happen" */
+		return "invalid";
+	}
+
+	return "?";
+}
 
 static int udc_proc_read(struct seq_file *m, void *v)
 {
@@ -1068,29 +1112,18 @@ static int udc_proc_read(struct seq_file *m, void *v)
 	tmp = readl(&regs->power_detect);
 	is_usb_connected = tmp & PW_DETECT;
 	seq_printf(m,
-		"%s - %s\n"
-		"%s version: %s %s\n"
-		"Gadget driver: %s\n"
-		"Host %s, %s\n"
-		"\n",
-		pci_name(dev->pdev), driver_desc,
-		driver_name, DRIVER_VERSION, dmastr(),
-		dev->driver ? dev->driver->driver.name : "(none)",
-		is_usb_connected
-			? ((tmp & PW_PULLUP) ? "full speed" : "powered")
-			: "disconnected",
-		({const char *state;
-		switch(dev->ep0state){
-		case EP0_DISCONNECT:	state = "ep0_disconnect"; break;
-		case EP0_IDLE:		state = "ep0_idle"; break;
-		case EP0_IN:		state = "ep0_in"; break;
-		case EP0_OUT:		state = "ep0_out"; break;
-		case EP0_STATUS:	state = "ep0_status"; break;
-		case EP0_STALL:		state = "ep0_stall"; break;
-		case EP0_SUSPEND:	state = "ep0_suspend"; break;
-		default:		state = "ep0_?"; break;
-		} state; })
-		);
+		   "%s - %s\n"
+		   "%s version: %s %s\n"
+		   "Gadget driver: %s\n"
+		   "Host %s, %s\n"
+		   "\n",
+		   pci_name(dev->pdev), driver_desc,
+		   driver_name, DRIVER_VERSION, dmastr(),
+		   dev->driver ? dev->driver->driver.name : "(none)",
+		   is_usb_connected
+			   ? ((tmp & PW_PULLUP) ? "full speed" : "powered")
+			   : "disconnected",
+		   udc_ep_state(dev->ep0state));
 
 	dump_intmask(m, "int_status", readl(&regs->int_status));
 	dump_intmask(m, "int_enable", readl(&regs->int_enable));
@@ -1099,31 +1132,30 @@ static int udc_proc_read(struct seq_file *m, void *v)
 		goto done;
 
 	/* registers for (active) device and ep0 */
-	if (seq_printf(m, "\nirqs %lu\ndataset %02x "
-			"single.bcs %02x.%02x state %x addr %u\n",
-			dev->irqs, readl(&regs->DataSet),
-			readl(&regs->EPxSingle), readl(&regs->EPxBCS),
-			readl(&regs->UsbState),
-			readl(&regs->address)) < 0)
+	seq_printf(m, "\nirqs %lu\ndataset %02x single.bcs %02x.%02x state %x addr %u\n",
+		   dev->irqs, readl(&regs->DataSet),
+		   readl(&regs->EPxSingle), readl(&regs->EPxBCS),
+		   readl(&regs->UsbState),
+		   readl(&regs->address));
+	if (seq_has_overflowed(m))
 		goto done;
 
 	tmp = readl(&regs->dma_master);
-	if (seq_printf(m,
-		"dma %03X =" EIGHTBITS "%s %s\n", tmp,
-		(tmp & MST_EOPB_DIS) ? " eopb-" : "",
-		(tmp & MST_EOPB_ENA) ? " eopb+" : "",
-		(tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
-		(tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
-
-		(tmp & MST_RD_EOPB) ? " eopb" : "",
-		(tmp & MST_RD_RESET) ? " in_reset" : "",
-		(tmp & MST_WR_RESET) ? " out_reset" : "",
-		(tmp & MST_RD_ENA) ? " IN" : "",
-
-		(tmp & MST_WR_ENA) ? " OUT" : "",
-		(tmp & MST_CONNECTION)
-			? "ep1in/ep2out"
-			: "ep1out/ep2in") < 0)
+	seq_printf(m, "dma %03X =" EIGHTBITS "%s %s\n",
+		   tmp,
+		   (tmp & MST_EOPB_DIS) ? " eopb-" : "",
+		   (tmp & MST_EOPB_ENA) ? " eopb+" : "",
+		   (tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
+		   (tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
+
+		   (tmp & MST_RD_EOPB) ? " eopb" : "",
+		   (tmp & MST_RD_RESET) ? " in_reset" : "",
+		   (tmp & MST_WR_RESET) ? " out_reset" : "",
+		   (tmp & MST_RD_ENA) ? " IN" : "",
+
+		   (tmp & MST_WR_ENA) ? " OUT" : "",
+		   (tmp & MST_CONNECTION) ? "ep1in/ep2out" : "ep1out/ep2in");
+	if (seq_has_overflowed(m))
 		goto done;
 
 	/* dump endpoint queues */
@@ -1135,44 +1167,23 @@ static int udc_proc_read(struct seq_file *m, void *v)
 			continue;
 
 		tmp = readl(ep->reg_status);
-		if (seq_printf(m,
-			"%s %s max %u %s, irqs %lu, "
-			"status %02x (%s) " FOURBITS "\n",
-			ep->ep.name,
-			ep->is_in ? "in" : "out",
-			ep->ep.maxpacket,
-			ep->dma ? "dma" : "pio",
-			ep->irqs,
-			tmp, ({ char *s;
-			switch (tmp & EPxSTATUS_EP_MASK) {
-			case EPxSTATUS_EP_READY:
-				s = "ready"; break;
-			case EPxSTATUS_EP_DATAIN:
-				s = "packet"; break;
-			case EPxSTATUS_EP_FULL:
-				s = "full"; break;
-			case EPxSTATUS_EP_TX_ERR:	// host will retry
-				s = "tx_err"; break;
-			case EPxSTATUS_EP_RX_ERR:
-				s = "rx_err"; break;
-			case EPxSTATUS_EP_BUSY:		/* ep0 only */
-				s = "busy"; break;
-			case EPxSTATUS_EP_STALL:
-				s = "stall"; break;
-			case EPxSTATUS_EP_INVALID:	// these "can't happen"
-				s = "invalid"; break;
-			default:
-				s = "?"; break;
-			} s; }),
-			(tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
-			(tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
-			(tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
-			(tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : ""
-			) < 0)
+		seq_printf(m, "%s %s max %u %s, irqs %lu, status %02x (%s) " FOURBITS "\n",
+			   ep->ep.name,
+			   ep->is_in ? "in" : "out",
+			   ep->ep.maxpacket,
+			   ep->dma ? "dma" : "pio",
+			   ep->irqs,
+			   tmp, udc_ep_status(tmp),
+			   (tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
+			   (tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
+			   (tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
+			   (tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : "");
+		if (seq_has_overflowed(m))
 			goto done;
 
 		if (list_empty(&ep->queue)) {
-			if (seq_puts(m, "\t(nothing queued)\n") < 0)
+			seq_puts(m, "\t(nothing queued)\n");
+			if (seq_has_overflowed(m))
 				goto done;
 			continue;
 		}
@@ -1187,10 +1198,10 @@ static int udc_proc_read(struct seq_file *m, void *v)
 			} else
 				tmp = req->req.actual;
 
-			if (seq_printf(m,
-				"\treq %p len %u/%u buf %p\n",
-				&req->req, tmp, req->req.length,
-				req->req.buf) < 0)
+			seq_printf(m, "\treq %p len %u/%u buf %p\n",
+				   &req->req, tmp, req->req.length,
+				   req->req.buf);
+			if (seq_has_overflowed(m))
 				goto done;
 		}
 	}
diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index 27fd41333f71..3b6a7852822d 100644
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
@@ -1803,23 +1803,14 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
 	req = container_of(_req, struct lpc32xx_request, req);
 	ep = container_of(_ep, struct lpc32xx_ep, ep);
 
-	if (!_req || !_req->complete || !_req->buf ||
+	if (!_ep || !_req || !_req->complete || !_req->buf ||
 	    !list_empty(&req->queue))
 		return -EINVAL;
 
 	udc = ep->udc;
 
-	if (!_ep) {
-		dev_dbg(udc->dev, "invalid ep\n");
-		return -EINVAL;
-	}
-
-
-	if ((!udc) || (!udc->driver) ||
-	    (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
-		dev_dbg(udc->dev, "invalid device\n");
-		return -EINVAL;
-	}
+	if (udc->gadget.speed == USB_SPEED_UNKNOWN)
+		return -EPIPE;
 
 	if (ep->lep) {
 		struct lpc32xx_usbd_dd_gad *dd;
diff --git a/drivers/usb/gadget/udc/net2280.c b/drivers/usb/gadget/udc/net2280.c
index d2c0bf65e345..9871b90195ad 100644
--- a/drivers/usb/gadget/udc/net2280.c
+++ b/drivers/usb/gadget/udc/net2280.c
@@ -80,6 +80,13 @@ static const char *const ep_name[] = {
 	"ep-e", "ep-f", "ep-g", "ep-h",
 };
 
+/* Endpoint names for usb3380 advance mode */
+static const char *const ep_name_adv[] = {
+	ep0name,
+	"ep1in", "ep2out", "ep3in", "ep4out",
+	"ep1out", "ep2in", "ep3out", "ep4in",
+};
+
 /* mode 0 == ep-{a,b,c,d} 1K fifo each
  * mode 1 == ep-{a,b} 2K fifo each, ep-{c,d} unavailable
  * mode 2 == ep-a 2K fifo, ep-{b,c} 1K each, ep-d unavailable
@@ -138,31 +145,44 @@ net2280_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
 	u32			max, tmp;
 	unsigned long		flags;
 	static const u32 ep_key[9] = { 1, 0, 1, 0, 1, 1, 0, 1, 0 };
+	int ret = 0;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
 	if (!_ep || !desc || ep->desc || _ep->name == ep0name ||
-			desc->bDescriptorType != USB_DT_ENDPOINT)
+			desc->bDescriptorType != USB_DT_ENDPOINT) {
+		pr_err("%s: failed at line=%d\n", __func__, __LINE__);
 		return -EINVAL;
+	}
 	dev = ep->dev;
-	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
-		return -ESHUTDOWN;
+	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {
+		ret = -ESHUTDOWN;
+		goto print_err;
+	}
 
 	/* erratum 0119 workaround ties up an endpoint number */
-	if ((desc->bEndpointAddress & 0x0f) == EP_DONTUSE)
-		return -EDOM;
+	if ((desc->bEndpointAddress & 0x0f) == EP_DONTUSE) {
+		ret = -EDOM;
+		goto print_err;
+	}
 
 	if (dev->quirks & PLX_SUPERSPEED) {
-		if ((desc->bEndpointAddress & 0x0f) >= 0x0c)
-			return -EDOM;
+		if ((desc->bEndpointAddress & 0x0f) >= 0x0c) {
+			ret = -EDOM;
+			goto print_err;
+		}
 		ep->is_in = !!usb_endpoint_dir_in(desc);
-		if (dev->enhanced_mode && ep->is_in && ep_key[ep->num])
-			return -EINVAL;
+		if (dev->enhanced_mode && ep->is_in && ep_key[ep->num]) {
+			ret = -EINVAL;
+			goto print_err;
+		}
 	}
 
 	/* sanity check ep-e/ep-f since their fifos are small */
 	max = usb_endpoint_maxp(desc) & 0x1fff;
-	if (ep->num > 4 && max > 64 && (dev->quirks & PLX_LEGACY))
-		return -ERANGE;
+	if (ep->num > 4 && max > 64 && (dev->quirks & PLX_LEGACY)) {
+		ret = -ERANGE;
+		goto print_err;
+	}
 
 	spin_lock_irqsave(&dev->lock, flags);
 	_ep->maxpacket = max & 0x7ff;
@@ -192,7 +212,8 @@ net2280_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
 		    (dev->gadget.speed == USB_SPEED_HIGH && max != 512) ||
 		    (dev->gadget.speed == USB_SPEED_FULL && max > 64)) {
 			spin_unlock_irqrestore(&dev->lock, flags);
-			return -ERANGE;
+			ret = -ERANGE;
+			goto print_err;
 		}
 	}
 	ep->is_iso = (tmp == USB_ENDPOINT_XFER_ISOC);
@@ -271,7 +292,11 @@ net2280_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
 
 	/* pci writes may still be posted */
 	spin_unlock_irqrestore(&dev->lock, flags);
-	return 0;
+	return ret;
+
+print_err:
+	dev_err(&ep->dev->pdev->dev, "%s: error=%d\n", __func__, ret);
+	return ret;
 }
 
 static int handshake(u32 __iomem *ptr, u32 mask, u32 done, int usec)
@@ -426,9 +451,10 @@ static int net2280_disable(struct usb_ep *_ep)
 	unsigned long		flags;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || !ep->desc || _ep->name == ep0name)
+	if (!_ep || !ep->desc || _ep->name == ep0name) {
+		pr_err("%s: Invalid ep=%p or ep->desc\n", __func__, _ep);
 		return -EINVAL;
-
+	}
 	spin_lock_irqsave(&ep->dev->lock, flags);
 	nuke(ep);
 
@@ -458,8 +484,10 @@ static struct usb_request
 	struct net2280_ep	*ep;
 	struct net2280_request	*req;
 
-	if (!_ep)
+	if (!_ep) {
+		pr_err("%s: Invalid ep\n", __func__);
 		return NULL;
+	}
 	ep = container_of(_ep, struct net2280_ep, ep);
 
 	req = kzalloc(sizeof(*req), gfp_flags);
@@ -491,8 +519,11 @@ static void net2280_free_request(struct usb_ep *_ep, struct usb_request *_req)
 	struct net2280_request	*req;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || !_req)
+	if (!_ep || !_req) {
+		dev_err(&ep->dev->pdev->dev, "%s: Inavlid ep=%p or req=%p\n",
+							__func__, _ep, _req);
 		return;
+	}
 
 	req = container_of(_req, struct net2280_request, req);
 	WARN_ON(!list_empty(&req->queue));
@@ -896,35 +927,44 @@ net2280_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
 	struct net2280_ep	*ep;
 	struct net2280		*dev;
 	unsigned long		flags;
+	int ret = 0;
 
 	/* we always require a cpu-view buffer, so that we can
 	 * always use pio (as fallback or whatever).
 	 */
-	req = container_of(_req, struct net2280_request, req);
-	if (!_req || !_req->complete || !_req->buf ||
-				!list_empty(&req->queue))
-		return -EINVAL;
-	if (_req->length > (~0 & DMA_BYTE_COUNT_MASK))
-		return -EDOM;
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || (!ep->desc && ep->num != 0))
+	if (!_ep || (!ep->desc && ep->num != 0)) {
+		pr_err("%s: Invalid ep=%p or ep->desc\n", __func__, _ep);
 		return -EINVAL;
+	}
+	req = container_of(_req, struct net2280_request, req);
+	if (!_req || !_req->complete || !_req->buf ||
+				!list_empty(&req->queue)) {
+		ret = -EINVAL;
+		goto print_err;
+	}
+	if (_req->length > (~0 & DMA_BYTE_COUNT_MASK)) {
+		ret = -EDOM;
+		goto print_err;
+	}
 	dev = ep->dev;
-	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
-		return -ESHUTDOWN;
+	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {
+		ret = -ESHUTDOWN;
+		goto print_err;
+	}
 
 	/* FIXME implement PIO fallback for ZLPs with DMA */
-	if (ep->dma && _req->length == 0)
-		return -EOPNOTSUPP;
+	if (ep->dma && _req->length == 0) {
+		ret = -EOPNOTSUPP;
+		goto print_err;
+	}
 
 	/* set up dma mapping in case the caller didn't */
 	if (ep->dma) {
-		int ret;
-
 		ret = usb_gadget_map_request(&dev->gadget, _req,
 				ep->is_in);
 		if (ret)
-			return ret;
+			goto print_err;
 	}
 
 	ep_vdbg(dev, "%s queue req %p, len %d buf %p\n",
@@ -1013,7 +1053,11 @@ done:
 	spin_unlock_irqrestore(&dev->lock, flags);
 
 	/* pci writes may still be posted */
-	return 0;
+	return ret;
+
+print_err:
+	dev_err(&ep->dev->pdev->dev, "%s: error=%d\n", __func__, ret);
+	return ret;
 }
 
 static inline void
@@ -1134,8 +1178,11 @@ static int net2280_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 	int			stopped;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || (!ep->desc && ep->num != 0) || !_req)
+	if (!_ep || (!ep->desc && ep->num != 0) || !_req) {
+		pr_err("%s: Invalid ep=%p or ep->desc or req=%p\n",
+						__func__, _ep, _req);
 		return -EINVAL;
+	}
 
 	spin_lock_irqsave(&ep->dev->lock, flags);
 	stopped = ep->stopped;
@@ -1157,6 +1204,8 @@ static int net2280_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 	}
 	if (&req->req != _req) {
 		spin_unlock_irqrestore(&ep->dev->lock, flags);
+		dev_err(&ep->dev->pdev->dev, "%s: Request mismatch\n",
+								__func__);
 		return -EINVAL;
 	}
 
@@ -1214,20 +1263,28 @@ net2280_set_halt_and_wedge(struct usb_ep *_ep, int value, int wedged)
 	int			retval = 0;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || (!ep->desc && ep->num != 0))
+	if (!_ep || (!ep->desc && ep->num != 0)) {
+		pr_err("%s: Invalid ep=%p or ep->desc\n", __func__, _ep);
 		return -EINVAL;
-	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN)
-		return -ESHUTDOWN;
+	}
+	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN) {
+		retval = -ESHUTDOWN;
+		goto print_err;
+	}
 	if (ep->desc /* not ep0 */ && (ep->desc->bmAttributes & 0x03)
-						== USB_ENDPOINT_XFER_ISOC)
-		return -EINVAL;
+						== USB_ENDPOINT_XFER_ISOC) {
+		retval = -EINVAL;
+		goto print_err;
+	}
 
 	spin_lock_irqsave(&ep->dev->lock, flags);
-	if (!list_empty(&ep->queue))
+	if (!list_empty(&ep->queue)) {
 		retval = -EAGAIN;
-	else if (ep->is_in && value && net2280_fifo_status(_ep) != 0)
+		goto print_unlock;
+	} else if (ep->is_in && value && net2280_fifo_status(_ep) != 0) {
 		retval = -EAGAIN;
-	else {
+		goto print_unlock;
+	} else {
 		ep_vdbg(ep->dev, "%s %s %s\n", _ep->name,
 				value ? "set" : "clear",
 				wedged ? "wedge" : "halt");
@@ -1251,6 +1308,12 @@ net2280_set_halt_and_wedge(struct usb_ep *_ep, int value, int wedged)
 	spin_unlock_irqrestore(&ep->dev->lock, flags);
 
 	return retval;
+
+print_unlock:
+	spin_unlock_irqrestore(&ep->dev->lock, flags);
+print_err:
+	dev_err(&ep->dev->pdev->dev, "%s: error=%d\n", __func__, retval);
+	return retval;
 }
 
 static int net2280_set_halt(struct usb_ep *_ep, int value)
@@ -1260,8 +1323,10 @@ static int net2280_set_halt(struct usb_ep *_ep, int value)
 
 static int net2280_set_wedge(struct usb_ep *_ep)
 {
-	if (!_ep || _ep->name == ep0name)
+	if (!_ep || _ep->name == ep0name) {
+		pr_err("%s: Invalid ep=%p or ep0\n", __func__, _ep);
 		return -EINVAL;
+	}
 	return net2280_set_halt_and_wedge(_ep, 1, 1);
 }
 
@@ -1271,14 +1336,22 @@ static int net2280_fifo_status(struct usb_ep *_ep)
 	u32			avail;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || (!ep->desc && ep->num != 0))
+	if (!_ep || (!ep->desc && ep->num != 0)) {
+		pr_err("%s: Invalid ep=%p or ep->desc\n", __func__, _ep);
 		return -ENODEV;
-	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN)
+	}
+	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN) {
+		dev_err(&ep->dev->pdev->dev,
+			"%s: Invalid driver=%p or speed=%d\n",
+			__func__, ep->dev->driver, ep->dev->gadget.speed);
 		return -ESHUTDOWN;
+	}
 
 	avail = readl(&ep->regs->ep_avail) & (BIT(12) - 1);
-	if (avail > ep->fifo_size)
+	if (avail > ep->fifo_size) {
+		dev_err(&ep->dev->pdev->dev, "%s: Fifo overflow\n", __func__);
 		return -EOVERFLOW;
+	}
 	if (ep->is_in)
 		avail = ep->fifo_size - avail;
 	return avail;
@@ -1289,10 +1362,16 @@ static void net2280_fifo_flush(struct usb_ep *_ep)
 	struct net2280_ep	*ep;
 
 	ep = container_of(_ep, struct net2280_ep, ep);
-	if (!_ep || (!ep->desc && ep->num != 0))
+	if (!_ep || (!ep->desc && ep->num != 0)) {
+		pr_err("%s: Invalid ep=%p or ep->desc\n", __func__, _ep);
 		return;
-	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN)
+	}
+	if (!ep->dev->driver || ep->dev->gadget.speed == USB_SPEED_UNKNOWN) {
+		dev_err(&ep->dev->pdev->dev,
+			"%s: Invalid driver=%p or speed=%d\n",
+			__func__, ep->dev->driver, ep->dev->gadget.speed);
 		return;
+	}
 
 	writel(BIT(FIFO_FLUSH), &ep->regs->ep_stat);
 	(void) readl(&ep->regs->ep_rsp);
@@ -1977,7 +2056,7 @@ static void usb_reinit_338x(struct net2280 *dev)
 	for (i = 0; i < dev->n_ep; i++) {
 		struct net2280_ep *ep = &dev->ep[i];
 
-		ep->ep.name = ep_name[i];
+		ep->ep.name = dev->enhanced_mode ? ep_name_adv[i] : ep_name[i];
 		ep->dev = dev;
 		ep->num = i;
 
@@ -1989,11 +2068,9 @@ static void usb_reinit_338x(struct net2280 *dev)
 			ep->regs = (struct net2280_ep_regs __iomem *)
 				(((void __iomem *)&dev->epregs[ne[i]]) +
 				ep_reg_addr[i]);
-			ep->fiforegs = &dev->fiforegs[i];
 		} else {
 			ep->cfg = &dev->epregs[i];
 			ep->regs = &dev->epregs[i];
-			ep->fiforegs = &dev->fiforegs[i];
 		}
 
 		ep->fifo_size = (i != 0) ? 2048 : 512;
@@ -2186,7 +2263,6 @@ static int net2280_start(struct usb_gadget *_gadget,
 		dev->ep[i].irqs = 0;
 
 	/* hook up the driver ... */
-	dev->softconnect = 1;
 	driver->driver.bus = NULL;
 	dev->driver = driver;
 
@@ -3052,6 +3128,8 @@ next_endpoints:
 		BIT(PCI_RETRY_ABORT_INTERRUPT))
 
 static void handle_stat1_irqs(struct net2280 *dev, u32 stat)
+__releases(dev->lock)
+__acquires(dev->lock)
 {
 	struct net2280_ep	*ep;
 	u32			tmp, num, mask, scratch;
@@ -3373,8 +3451,6 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		u32 usbstat;
 		dev->usb_ext = (struct usb338x_usb_ext_regs __iomem *)
 							(base + 0x00b4);
-		dev->fiforegs = (struct usb338x_fifo_regs __iomem *)
-							(base + 0x0500);
 		dev->llregs = (struct usb338x_ll_regs __iomem *)
 							(base + 0x0700);
 		dev->ll_lfps_regs = (struct usb338x_ll_lfps_regs __iomem *)
diff --git a/drivers/usb/gadget/udc/net2280.h b/drivers/usb/gadget/udc/net2280.h
index ac8d5a20a378..4dff60d34f73 100644
--- a/drivers/usb/gadget/udc/net2280.h
+++ b/drivers/usb/gadget/udc/net2280.h
@@ -96,7 +96,6 @@ struct net2280_ep {
 	struct net2280_ep_regs			__iomem *regs;
 	struct net2280_dma_regs			__iomem *dma;
 	struct net2280_dma			*dummy;
-	struct usb338x_fifo_regs __iomem *fiforegs;
 	dma_addr_t				td_dma;	/* of dummy */
 	struct net2280				*dev;
 	unsigned long				irqs;
@@ -181,7 +180,6 @@ struct net2280 {
 	struct net2280_dma_regs		__iomem *dma;
 	struct net2280_dep_regs		__iomem *dep;
 	struct net2280_ep_regs		__iomem *epregs;
-	struct usb338x_fifo_regs	__iomem *fiforegs;
 	struct usb338x_ll_regs		__iomem *llregs;
 	struct usb338x_ll_lfps_regs	__iomem *ll_lfps_regs;
 	struct usb338x_ll_tsn_regs	__iomem *ll_tsn_regs;
diff --git a/drivers/usb/gadget/udc/pxa27x_udc.c b/drivers/usb/gadget/udc/pxa27x_udc.c
index f0ae143dab6d..b51226abade6 100644
--- a/drivers/usb/gadget/udc/pxa27x_udc.c
+++ b/drivers/usb/gadget/udc/pxa27x_udc.c
@@ -93,50 +93,46 @@ static void handle_ep(struct pxa_ep *ep);
 static int state_dbg_show(struct seq_file *s, void *p)
 {
 	struct pxa_udc *udc = s->private;
-	int pos = 0, ret;
 	u32 tmp;
 
-	ret = -ENODEV;
 	if (!udc->driver)
-		goto out;
+		return -ENODEV;
 
 	/* basic device status */
-	pos += seq_printf(s, DRIVER_DESC "\n"
-			 "%s version: %s\nGadget driver: %s\n",
-			 driver_name, DRIVER_VERSION,
-			 udc->driver ? udc->driver->driver.name : "(none)");
+	seq_printf(s, DRIVER_DESC "\n"
+		   "%s version: %s\n"
+		   "Gadget driver: %s\n",
+		   driver_name, DRIVER_VERSION,
+		   udc->driver ? udc->driver->driver.name : "(none)");
 
 	tmp = udc_readl(udc, UDCCR);
-	pos += seq_printf(s,
-			 "udccr=0x%0x(%s%s%s%s%s%s%s%s%s%s), "
-			 "con=%d,inter=%d,altinter=%d\n", tmp,
-			 (tmp & UDCCR_OEN) ? " oen":"",
-			 (tmp & UDCCR_AALTHNP) ? " aalthnp":"",
-			 (tmp & UDCCR_AHNP) ? " rem" : "",
-			 (tmp & UDCCR_BHNP) ? " rstir" : "",
-			 (tmp & UDCCR_DWRE) ? " dwre" : "",
-			 (tmp & UDCCR_SMAC) ? " smac" : "",
-			 (tmp & UDCCR_EMCE) ? " emce" : "",
-			 (tmp & UDCCR_UDR) ? " udr" : "",
-			 (tmp & UDCCR_UDA) ? " uda" : "",
-			 (tmp & UDCCR_UDE) ? " ude" : "",
-			 (tmp & UDCCR_ACN) >> UDCCR_ACN_S,
-			 (tmp & UDCCR_AIN) >> UDCCR_AIN_S,
-			 (tmp & UDCCR_AAISN) >> UDCCR_AAISN_S);
+	seq_printf(s,
+		   "udccr=0x%0x(%s%s%s%s%s%s%s%s%s%s), con=%d,inter=%d,altinter=%d\n",
+		   tmp,
+		   (tmp & UDCCR_OEN) ? " oen":"",
+		   (tmp & UDCCR_AALTHNP) ? " aalthnp":"",
+		   (tmp & UDCCR_AHNP) ? " rem" : "",
+		   (tmp & UDCCR_BHNP) ? " rstir" : "",
+		   (tmp & UDCCR_DWRE) ? " dwre" : "",
+		   (tmp & UDCCR_SMAC) ? " smac" : "",
+		   (tmp & UDCCR_EMCE) ? " emce" : "",
+		   (tmp & UDCCR_UDR) ? " udr" : "",
+		   (tmp & UDCCR_UDA) ? " uda" : "",
+		   (tmp & UDCCR_UDE) ? " ude" : "",
+		   (tmp & UDCCR_ACN) >> UDCCR_ACN_S,
+		   (tmp & UDCCR_AIN) >> UDCCR_AIN_S,
+		   (tmp & UDCCR_AAISN) >> UDCCR_AAISN_S);
 	/* registers for device and ep0 */
-	pos += seq_printf(s, "udcicr0=0x%08x udcicr1=0x%08x\n",
-			udc_readl(udc, UDCICR0), udc_readl(udc, UDCICR1));
-	pos += seq_printf(s, "udcisr0=0x%08x udcisr1=0x%08x\n",
-			udc_readl(udc, UDCISR0), udc_readl(udc, UDCISR1));
-	pos += seq_printf(s, "udcfnr=%d\n", udc_readl(udc, UDCFNR));
-	pos += seq_printf(s, "irqs: reset=%lu, suspend=%lu, resume=%lu, "
-			"reconfig=%lu\n",
-			udc->stats.irqs_reset, udc->stats.irqs_suspend,
-			udc->stats.irqs_resume, udc->stats.irqs_reconfig);
-
-	ret = 0;
-out:
-	return ret;
+	seq_printf(s, "udcicr0=0x%08x udcicr1=0x%08x\n",
+		   udc_readl(udc, UDCICR0), udc_readl(udc, UDCICR1));
+	seq_printf(s, "udcisr0=0x%08x udcisr1=0x%08x\n",
+		   udc_readl(udc, UDCISR0), udc_readl(udc, UDCISR1));
+	seq_printf(s, "udcfnr=%d\n", udc_readl(udc, UDCFNR));
+	seq_printf(s, "irqs: reset=%lu, suspend=%lu, resume=%lu, reconfig=%lu\n",
+		   udc->stats.irqs_reset, udc->stats.irqs_suspend,
+		   udc->stats.irqs_resume, udc->stats.irqs_reconfig);
+
+	return 0;
 }
 
 static int queues_dbg_show(struct seq_file *s, void *p)
@@ -144,75 +140,67 @@ static int queues_dbg_show(struct seq_file *s, void *p)
 	struct pxa_udc *udc = s->private;
 	struct pxa_ep *ep;
 	struct pxa27x_request *req;
-	int pos = 0, i, maxpkt, ret;
+	int i, maxpkt;
 
-	ret = -ENODEV;
 	if (!udc->driver)
-		goto out;
+		return -ENODEV;
 
 	/* dump endpoint queues */
 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
 		ep = &udc->pxa_ep[i];
 		maxpkt = ep->fifo_size;
-		pos += seq_printf(s,  "%-12s max_pkt=%d %s\n",
-				EPNAME(ep), maxpkt, "pio");
+		seq_printf(s,  "%-12s max_pkt=%d %s\n",
+			   EPNAME(ep), maxpkt, "pio");
 
 		if (list_empty(&ep->queue)) {
-			pos += seq_printf(s, "\t(nothing queued)\n");
+			seq_puts(s, "\t(nothing queued)\n");
 			continue;
 		}
 
 		list_for_each_entry(req, &ep->queue, queue) {
-			pos += seq_printf(s,  "\treq %p len %d/%d buf %p\n",
-					&req->req, req->req.actual,
-					req->req.length, req->req.buf);
+			seq_printf(s,  "\treq %p len %d/%d buf %p\n",
+				   &req->req, req->req.actual,
+				   req->req.length, req->req.buf);
 		}
 	}
 
-	ret = 0;
-out:
-	return ret;
+	return 0;
 }
 
 static int eps_dbg_show(struct seq_file *s, void *p)
 {
 	struct pxa_udc *udc = s->private;
 	struct pxa_ep *ep;
-	int pos = 0, i, ret;
+	int i;
 	u32 tmp;
 
-	ret = -ENODEV;
 	if (!udc->driver)
-		goto out;
+		return -ENODEV;
 
 	ep = &udc->pxa_ep[0];
 	tmp = udc_ep_readl(ep, UDCCSR);
-	pos += seq_printf(s, "udccsr0=0x%03x(%s%s%s%s%s%s%s)\n", tmp,
-			 (tmp & UDCCSR0_SA) ? " sa" : "",
-			 (tmp & UDCCSR0_RNE) ? " rne" : "",
-			 (tmp & UDCCSR0_FST) ? " fst" : "",
-			 (tmp & UDCCSR0_SST) ? " sst" : "",
-			 (tmp & UDCCSR0_DME) ? " dme" : "",
-			 (tmp & UDCCSR0_IPR) ? " ipr" : "",
-			 (tmp & UDCCSR0_OPC) ? " opc" : "");
+	seq_printf(s, "udccsr0=0x%03x(%s%s%s%s%s%s%s)\n",
+		   tmp,
+		   (tmp & UDCCSR0_SA) ? " sa" : "",
+		   (tmp & UDCCSR0_RNE) ? " rne" : "",
+		   (tmp & UDCCSR0_FST) ? " fst" : "",
+		   (tmp & UDCCSR0_SST) ? " sst" : "",
+		   (tmp & UDCCSR0_DME) ? " dme" : "",
+		   (tmp & UDCCSR0_IPR) ? " ipr" : "",
+		   (tmp & UDCCSR0_OPC) ? " opc" : "");
 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
 		ep = &udc->pxa_ep[i];
 		tmp = i? udc_ep_readl(ep, UDCCR) : udc_readl(udc, UDCCR);
-		pos += seq_printf(s, "%-12s: "
-				"IN %lu(%lu reqs), OUT %lu(%lu reqs), "
-				"irqs=%lu, udccr=0x%08x, udccsr=0x%03x, "
-				"udcbcr=%d\n",
-				EPNAME(ep),
-				ep->stats.in_bytes, ep->stats.in_ops,
-				ep->stats.out_bytes, ep->stats.out_ops,
-				ep->stats.irqs,
-				tmp, udc_ep_readl(ep, UDCCSR),
-				udc_ep_readl(ep, UDCBCR));
+		seq_printf(s, "%-12s: IN %lu(%lu reqs), OUT %lu(%lu reqs), irqs=%lu, udccr=0x%08x, udccsr=0x%03x, udcbcr=%d\n",
+			   EPNAME(ep),
+			   ep->stats.in_bytes, ep->stats.in_ops,
+			   ep->stats.out_bytes, ep->stats.out_ops,
+			   ep->stats.irqs,
+			   tmp, udc_ep_readl(ep, UDCCSR),
+			   udc_ep_readl(ep, UDCBCR));
 	}
 
-	ret = 0;
-out:
-	return ret;
+	return 0;
 }
 
 static int eps_dbg_open(struct inode *inode, struct file *file)
diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c
index 5a81cb086b99..d69c35558f68 100644
--- a/drivers/usb/gadget/udc/udc-core.c
+++ b/drivers/usb/gadget/udc/udc-core.c
@@ -35,6 +35,8 @@
  * @dev - the child device to the actual controller
  * @gadget - the gadget. For use by the class code
  * @list - for use by the udc class driver
+ * @vbus - for udcs who care about vbus status, this value is real vbus status;
+ * for udcs who do not care about vbus status, this value is always true
  *
  * This represents the internal data structure which is used by the UDC-class
  * to hold information about udc driver and gadget together.
@@ -44,6 +46,7 @@ struct usb_udc {
 	struct usb_gadget		*gadget;
 	struct device			dev;
 	struct list_head		list;
+	bool				vbus;
 };
 
 static struct class *udc_class;
@@ -128,21 +131,11 @@ EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
 
 static void usb_gadget_state_work(struct work_struct *work)
 {
-	struct usb_gadget	*gadget = work_to_gadget(work);
-	struct usb_udc		*udc = NULL;
-
-	mutex_lock(&udc_lock);
-	list_for_each_entry(udc, &udc_list, list)
-		if (udc->gadget == gadget)
-			goto found;
-	mutex_unlock(&udc_lock);
-
-	return;
-
-found:
-	mutex_unlock(&udc_lock);
+	struct usb_gadget *gadget = work_to_gadget(work);
+	struct usb_udc *udc = gadget->udc;
 
-	sysfs_notify(&udc->dev.kobj, NULL, "state");
+	if (udc)
+		sysfs_notify(&udc->dev.kobj, NULL, "state");
 }
 
 void usb_gadget_set_state(struct usb_gadget *gadget,
@@ -155,6 +148,34 @@ EXPORT_SYMBOL_GPL(usb_gadget_set_state);
 
 /* ------------------------------------------------------------------------- */
 
+static void usb_udc_connect_control(struct usb_udc *udc)
+{
+	if (udc->vbus)
+		usb_gadget_connect(udc->gadget);
+	else
+		usb_gadget_disconnect(udc->gadget);
+}
+
+/**
+ * usb_udc_vbus_handler - updates the udc core vbus status, and try to
+ * connect or disconnect gadget
+ * @gadget: The gadget which vbus change occurs
+ * @status: The vbus status
+ *
+ * The udc driver calls it when it wants to connect or disconnect gadget
+ * according to vbus status.
+ */
+void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
+{
+	struct usb_udc *udc = gadget->udc;
+
+	if (udc) {
+		udc->vbus = status;
+		usb_udc_connect_control(udc);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
+
 /**
  * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
  * @gadget: The gadget which bus reset occurs
@@ -278,6 +299,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 		goto err3;
 
 	udc->gadget = gadget;
+	gadget->udc = udc;
 
 	mutex_lock(&udc_lock);
 	list_add_tail(&udc->list, &udc_list);
@@ -287,6 +309,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 		goto err4;
 
 	usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
+	udc->vbus = true;
 
 	mutex_unlock(&udc_lock);
 
@@ -348,21 +371,14 @@ static void usb_gadget_remove_driver(struct usb_udc *udc)
  */
 void usb_del_gadget_udc(struct usb_gadget *gadget)
 {
-	struct usb_udc		*udc = NULL;
+	struct usb_udc *udc = gadget->udc;
 
-	mutex_lock(&udc_lock);
-	list_for_each_entry(udc, &udc_list, list)
-		if (udc->gadget == gadget)
-			goto found;
-
-	dev_err(gadget->dev.parent, "gadget not registered.\n");
-	mutex_unlock(&udc_lock);
-
-	return;
+	if (!udc)
+		return;
 
-found:
 	dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
 
+	mutex_lock(&udc_lock);
 	list_del(&udc->list);
 	mutex_unlock(&udc_lock);
 
@@ -397,7 +413,7 @@ static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *dri
 		driver->unbind(udc->gadget);
 		goto err1;
 	}
-	usb_gadget_connect(udc->gadget);
+	usb_udc_connect_control(udc);
 
 	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
 	return 0;