1 files changed, 666 insertions, 136 deletions

diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index 5eea44823ca0..3ddfd4f66f0b 100644
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -1,12 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * f_hid.c -- USB HID function driver
  *
  * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
- *
- * 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/kernel.h>
@@ -19,18 +15,35 @@
 #include <linux/uaccess.h>
 #include <linux/wait.h>
 #include <linux/sched.h>
+#include <linux/workqueue.h>
+#include <linux/usb/func_utils.h>
 #include <linux/usb/g_hid.h>
+#include <uapi/linux/usb/g_hid.h>
 
-#include "u_f.h"
 #include "u_hid.h"
 
 #define HIDG_MINORS	4
 
+/*
+ * Most operating systems seem to allow for 5000ms timeout, we will allow
+ * userspace half that time to respond before we return an empty report.
+ */
+#define GET_REPORT_TIMEOUT_MS 2500
+
 static int major, minors;
-static struct class *hidg_class;
+
+static const struct class hidg_class = {
+	.name = "hidg",
+};
+
 static DEFINE_IDA(hidg_ida);
 static DEFINE_MUTEX(hidg_ida_lock); /* protects access to hidg_ida */
 
+struct report_entry {
+	struct usb_hidg_report report_data;
+	struct list_head node;
+};
+
 /*-------------------------------------------------------------------------*/
 /*                            HID gadget struct                            */
 
@@ -44,15 +57,34 @@ struct f_hidg {
 	/* configuration */
 	unsigned char			bInterfaceSubClass;
 	unsigned char			bInterfaceProtocol;
+	unsigned char			protocol;
+	unsigned char			idle;
 	unsigned short			report_desc_length;
 	char				*report_desc;
 	unsigned short			report_length;
+	unsigned char			interval;
+	bool				interval_user_set;
+
+	/*
+	 * use_out_ep - if true, the OUT Endpoint (interrupt out method)
+	 *              will be used to receive reports from the host
+	 *              using functions with the "intout" suffix.
+	 *              Otherwise, the OUT Endpoint will not be configured
+	 *              and the SETUP/SET_REPORT method ("ssreport" suffix)
+	 *              will be used to receive reports.
+	 */
+	bool				use_out_ep;
 
 	/* recv report */
-	struct list_head		completed_out_req;
 	spinlock_t			read_spinlock;
 	wait_queue_head_t		read_queue;
+	bool				disabled;
+	/* recv report - interrupt out only (use_out_ep == 1) */
+	struct list_head		completed_out_req;
 	unsigned int			qlen;
+	/* recv report - setup set_report only (use_out_ep == 0) */
+	char				*set_report_buf;
+	unsigned int			set_report_length;
 
 	/* send report */
 	spinlock_t			write_spinlock;
@@ -60,7 +92,20 @@ struct f_hidg {
 	wait_queue_head_t		write_queue;
 	struct usb_request		*req;
 
-	int				minor;
+	/* get report */
+	struct usb_request		*get_req;
+	struct usb_hidg_report		get_report;
+	bool				get_report_returned;
+	int				get_report_req_report_id;
+	int				get_report_req_report_length;
+	spinlock_t			get_report_spinlock;
+	wait_queue_head_t		get_queue;    /* Waiting for userspace response */
+	wait_queue_head_t		get_id_queue; /* Get ID came in */
+	struct work_struct		work;
+	struct workqueue_struct		*workqueue;
+	struct list_head		report_list;
+
+	struct device			dev;
 	struct cdev			cdev;
 	struct usb_function		func;
 
@@ -73,6 +118,15 @@ static inline struct f_hidg *func_to_hidg(struct usb_function *f)
 	return container_of(f, struct f_hidg, func);
 }
 
+static void hidg_release(struct device *dev)
+{
+	struct f_hidg *hidg = container_of(dev, struct f_hidg, dev);
+
+	kfree(hidg->report_desc);
+	kfree(hidg->set_report_buf);
+	kfree(hidg);
+}
+
 /*-------------------------------------------------------------------------*/
 /*                           Static descriptors                            */
 
@@ -81,7 +135,7 @@ static struct usb_interface_descriptor hidg_interface_desc = {
 	.bDescriptorType	= USB_DT_INTERFACE,
 	/* .bInterfaceNumber	= DYNAMIC */
 	.bAlternateSetting	= 0,
-	.bNumEndpoints		= 2,
+	/* .bNumEndpoints	= DYNAMIC (depends on use_out_ep) */
 	.bInterfaceClass	= USB_CLASS_HID,
 	/* .bInterfaceSubClass	= DYNAMIC */
 	/* .bInterfaceProtocol	= DYNAMIC */
@@ -91,11 +145,11 @@ static struct usb_interface_descriptor hidg_interface_desc = {
 static struct hid_descriptor hidg_desc = {
 	.bLength			= sizeof hidg_desc,
 	.bDescriptorType		= HID_DT_HID,
-	.bcdHID				= 0x0101,
+	.bcdHID				= cpu_to_le16(0x0101),
 	.bCountryCode			= 0x00,
 	.bNumDescriptors		= 0x1,
-	/*.desc[0].bDescriptorType	= DYNAMIC */
-	/*.desc[0].wDescriptorLenght	= DYNAMIC */
+	/*.rpt_desc.bDescriptorType	= DYNAMIC */
+	/*.rpt_desc.wDescriptorLength	= DYNAMIC */
 };
 
 /* Super-Speed Support */
@@ -106,10 +160,7 @@ static struct usb_endpoint_descriptor hidg_ss_in_ep_desc = {
 	.bEndpointAddress	= USB_DIR_IN,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 4, /* FIXME: Add this field in the
-				      * HID gadget configuration?
-				      * (struct hidg_func_descriptor)
-				      */
+	/*.bInterval		= DYNAMIC */
 };
 
 static struct usb_ss_ep_comp_descriptor hidg_ss_in_comp_desc = {
@@ -127,10 +178,7 @@ static struct usb_endpoint_descriptor hidg_ss_out_ep_desc = {
 	.bEndpointAddress	= USB_DIR_OUT,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 4, /* FIXME: Add this field in the
-				      * HID gadget configuration?
-				      * (struct hidg_func_descriptor)
-				      */
+	/*.bInterval		= DYNAMIC */
 };
 
 static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = {
@@ -142,7 +190,7 @@ static struct usb_ss_ep_comp_descriptor hidg_ss_out_comp_desc = {
 	/* .wBytesPerInterval   = DYNAMIC */
 };
 
-static struct usb_descriptor_header *hidg_ss_descriptors[] = {
+static struct usb_descriptor_header *hidg_ss_descriptors_intout[] = {
 	(struct usb_descriptor_header *)&hidg_interface_desc,
 	(struct usb_descriptor_header *)&hidg_desc,
 	(struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
@@ -152,6 +200,14 @@ static struct usb_descriptor_header *hidg_ss_descriptors[] = {
 	NULL,
 };
 
+static struct usb_descriptor_header *hidg_ss_descriptors_ssreport[] = {
+	(struct usb_descriptor_header *)&hidg_interface_desc,
+	(struct usb_descriptor_header *)&hidg_desc,
+	(struct usb_descriptor_header *)&hidg_ss_in_ep_desc,
+	(struct usb_descriptor_header *)&hidg_ss_in_comp_desc,
+	NULL,
+};
+
 /* High-Speed Support */
 
 static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
@@ -160,10 +216,7 @@ static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
 	.bEndpointAddress	= USB_DIR_IN,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 4, /* FIXME: Add this field in the
-				      * HID gadget configuration?
-				      * (struct hidg_func_descriptor)
-				      */
+	/* .bInterval		= DYNAMIC */
 };
 
 static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
@@ -172,13 +225,10 @@ static struct usb_endpoint_descriptor hidg_hs_out_ep_desc = {
 	.bEndpointAddress	= USB_DIR_OUT,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 4, /* FIXME: Add this field in the
-				      * HID gadget configuration?
-				      * (struct hidg_func_descriptor)
-				      */
+	/*.bInterval		= DYNAMIC */
 };
 
-static struct usb_descriptor_header *hidg_hs_descriptors[] = {
+static struct usb_descriptor_header *hidg_hs_descriptors_intout[] = {
 	(struct usb_descriptor_header *)&hidg_interface_desc,
 	(struct usb_descriptor_header *)&hidg_desc,
 	(struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
@@ -186,6 +236,13 @@ static struct usb_descriptor_header *hidg_hs_descriptors[] = {
 	NULL,
 };
 
+static struct usb_descriptor_header *hidg_hs_descriptors_ssreport[] = {
+	(struct usb_descriptor_header *)&hidg_interface_desc,
+	(struct usb_descriptor_header *)&hidg_desc,
+	(struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
+	NULL,
+};
+
 /* Full-Speed Support */
 
 static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
@@ -194,10 +251,7 @@ static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
 	.bEndpointAddress	= USB_DIR_IN,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 10, /* FIXME: Add this field in the
-				       * HID gadget configuration?
-				       * (struct hidg_func_descriptor)
-				       */
+	/*.bInterval		= DYNAMIC */
 };
 
 static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
@@ -206,13 +260,10 @@ static struct usb_endpoint_descriptor hidg_fs_out_ep_desc = {
 	.bEndpointAddress	= USB_DIR_OUT,
 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
 	/*.wMaxPacketSize	= DYNAMIC */
-	.bInterval		= 10, /* FIXME: Add this field in the
-				       * HID gadget configuration?
-				       * (struct hidg_func_descriptor)
-				       */
+	/*.bInterval		= DYNAMIC */
 };
 
-static struct usb_descriptor_header *hidg_fs_descriptors[] = {
+static struct usb_descriptor_header *hidg_fs_descriptors_intout[] = {
 	(struct usb_descriptor_header *)&hidg_interface_desc,
 	(struct usb_descriptor_header *)&hidg_desc,
 	(struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
@@ -220,6 +271,13 @@ static struct usb_descriptor_header *hidg_fs_descriptors[] = {
 	NULL,
 };
 
+static struct usb_descriptor_header *hidg_fs_descriptors_ssreport[] = {
+	(struct usb_descriptor_header *)&hidg_interface_desc,
+	(struct usb_descriptor_header *)&hidg_desc,
+	(struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
+	NULL,
+};
+
 /*-------------------------------------------------------------------------*/
 /*                                 Strings                                 */
 
@@ -243,8 +301,8 @@ static struct usb_gadget_strings *ct_func_strings[] = {
 /*-------------------------------------------------------------------------*/
 /*                              Char Device                                */
 
-static ssize_t f_hidg_read(struct file *file, char __user *buffer,
-			size_t count, loff_t *ptr)
+static ssize_t f_hidg_intout_read(struct file *file, char __user *buffer,
+				  size_t count, loff_t *ptr)
 {
 	struct f_hidg *hidg = file->private_data;
 	struct f_hidg_req_list *list;
@@ -255,25 +313,27 @@ static ssize_t f_hidg_read(struct file *file, char __user *buffer,
 	if (!count)
 		return 0;
 
-	if (!access_ok(VERIFY_WRITE, buffer, count))
-		return -EFAULT;
-
 	spin_lock_irqsave(&hidg->read_spinlock, flags);
 
-#define READ_COND (!list_empty(&hidg->completed_out_req))
+#define READ_COND_INTOUT (!list_empty(&hidg->completed_out_req) || hidg->disabled)
 
 	/* wait for at least one buffer to complete */
-	while (!READ_COND) {
+	while (!READ_COND_INTOUT) {
 		spin_unlock_irqrestore(&hidg->read_spinlock, flags);
 		if (file->f_flags & O_NONBLOCK)
 			return -EAGAIN;
 
-		if (wait_event_interruptible(hidg->read_queue, READ_COND))
+		if (wait_event_interruptible(hidg->read_queue, READ_COND_INTOUT))
 			return -ERESTARTSYS;
 
 		spin_lock_irqsave(&hidg->read_spinlock, flags);
 	}
 
+	if (hidg->disabled) {
+		spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+		return -ESHUTDOWN;
+	}
+
 	/* pick the first one */
 	list = list_first_entry(&hidg->completed_out_req,
 				struct f_hidg_req_list, list);
@@ -318,6 +378,60 @@ static ssize_t f_hidg_read(struct file *file, char __user *buffer,
 	return count;
 }
 
+#define READ_COND_SSREPORT (hidg->set_report_buf != NULL || hidg->disabled)
+
+static ssize_t f_hidg_ssreport_read(struct file *file, char __user *buffer,
+				    size_t count, loff_t *ptr)
+{
+	struct f_hidg *hidg = file->private_data;
+	char *tmp_buf = NULL;
+	unsigned long flags;
+
+	if (!count)
+		return 0;
+
+	spin_lock_irqsave(&hidg->read_spinlock, flags);
+
+	while (!READ_COND_SSREPORT) {
+		spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+		if (file->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+
+		if (wait_event_interruptible(hidg->read_queue, READ_COND_SSREPORT))
+			return -ERESTARTSYS;
+
+		spin_lock_irqsave(&hidg->read_spinlock, flags);
+	}
+
+	count = min_t(unsigned int, count, hidg->set_report_length);
+	tmp_buf = hidg->set_report_buf;
+	hidg->set_report_buf = NULL;
+
+	spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+	if (tmp_buf != NULL) {
+		count -= copy_to_user(buffer, tmp_buf, count);
+		kfree(tmp_buf);
+	} else {
+		count = -ENOMEM;
+	}
+
+	wake_up(&hidg->read_queue);
+
+	return count;
+}
+
+static ssize_t f_hidg_read(struct file *file, char __user *buffer,
+			   size_t count, loff_t *ptr)
+{
+	struct f_hidg *hidg = file->private_data;
+
+	if (hidg->use_out_ep)
+		return f_hidg_intout_read(file, buffer, count, ptr);
+	else
+		return f_hidg_ssreport_read(file, buffer, count, ptr);
+}
+
 static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
 {
 	struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;
@@ -342,11 +456,13 @@ static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
 	unsigned long flags;
 	ssize_t status = -ENOMEM;
 
-	if (!access_ok(VERIFY_READ, buffer, count))
-		return -EFAULT;
-
 	spin_lock_irqsave(&hidg->write_spinlock, flags);
 
+	if (!hidg->req) {
+		spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+		return -ESHUTDOWN;
+	}
+
 #define WRITE_COND (!hidg->write_pending)
 try_again:
 	/* write queue */
@@ -367,8 +483,14 @@ try_again:
 	count  = min_t(unsigned, count, hidg->report_length);
 
 	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
-	status = copy_from_user(req->buf, buffer, count);
 
+	if (!req) {
+		ERROR(hidg->func.config->cdev, "hidg->req is NULL\n");
+		status = -ESHUTDOWN;
+		goto release_write_pending;
+	}
+
+	status = copy_from_user(req->buf, buffer, count);
 	if (status != 0) {
 		ERROR(hidg->func.config->cdev,
 			"copy_from_user error\n");
@@ -389,25 +511,28 @@ try_again:
 	}
 
 	req->status   = 0;
-	req->zero     = 0;
+	req->zero     = 1;
 	req->length   = count;
 	req->complete = f_hidg_req_complete;
 	req->context  = hidg;
 
+	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+
+	if (!hidg->in_ep->enabled) {
+		ERROR(hidg->func.config->cdev, "in_ep is disabled\n");
+		status = -ESHUTDOWN;
+		goto release_write_pending;
+	}
+
 	status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC);
-	if (status < 0) {
-		ERROR(hidg->func.config->cdev,
-			"usb_ep_queue error on int endpoint %zd\n", status);
-		goto release_write_pending_unlocked;
-	} else {
+	if (status < 0)
+		goto release_write_pending;
+	else
 		status = count;
-	}
-	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 
 	return status;
 release_write_pending:
 	spin_lock_irqsave(&hidg->write_spinlock, flags);
-release_write_pending_unlocked:
 	hidg->write_pending = 0;
 	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 
@@ -416,25 +541,205 @@ release_write_pending_unlocked:
 	return status;
 }
 
-static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
+static struct report_entry *f_hidg_search_for_report(struct f_hidg *hidg, u8 report_id)
+{
+	struct list_head	*ptr;
+	struct report_entry	*entry;
+
+	list_for_each(ptr, &hidg->report_list) {
+		entry = list_entry(ptr, struct report_entry, node);
+		if (entry->report_data.report_id == report_id)
+			return entry;
+	}
+
+	return NULL;
+}
+
+static void get_report_workqueue_handler(struct work_struct *work)
+{
+	struct f_hidg *hidg = container_of(work, struct f_hidg, work);
+	struct usb_composite_dev *cdev = hidg->func.config->cdev;
+	struct usb_request		*req;
+	struct report_entry *ptr;
+	unsigned long	flags;
+
+	int status = 0;
+
+	spin_lock_irqsave(&hidg->get_report_spinlock, flags);
+	req = hidg->get_req;
+	if (!req) {
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+		return;
+	}
+
+	req->zero = 0;
+	req->length = min_t(unsigned int, min_t(unsigned int, hidg->get_report_req_report_length,
+							      hidg->report_length),
+					  MAX_REPORT_LENGTH);
+
+	/* Check if there is a response available for immediate response */
+	ptr = f_hidg_search_for_report(hidg, hidg->get_report_req_report_id);
+	if (ptr && !ptr->report_data.userspace_req) {
+		/* Report exists in list and it is to be used for immediate response */
+		req->buf = ptr->report_data.data;
+		status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+		hidg->get_report_returned = true;
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+	} else {
+		/*
+		 * Report does not exist in list or should not be immediately sent
+		 * i.e. give userspace time to respond
+		 */
+		hidg->get_report_returned = false;
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+		wake_up(&hidg->get_id_queue);
+#define GET_REPORT_COND (!hidg->get_report_returned)
+		/* Wait until userspace has responded or timeout */
+		status = wait_event_interruptible_timeout(hidg->get_queue, !GET_REPORT_COND,
+					msecs_to_jiffies(GET_REPORT_TIMEOUT_MS));
+		spin_lock_irqsave(&hidg->get_report_spinlock, flags);
+		req = hidg->get_req;
+		if (!req) {
+			spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+			return;
+		}
+		if (status == 0 && !hidg->get_report_returned) {
+			/* GET_REPORT request was not serviced by userspace within timeout period */
+			VDBG(cdev, "get_report : userspace timeout.\n");
+			hidg->get_report_returned = true;
+		}
+
+		/* Search again for report ID in list and respond to GET_REPORT request */
+		ptr = f_hidg_search_for_report(hidg, hidg->get_report_req_report_id);
+		if (ptr) {
+			/*
+			 * Either get an updated response just serviced by userspace
+			 * or send the latest response in the list
+			 */
+			req->buf = ptr->report_data.data;
+		} else {
+			/* If there are no prevoiusly sent reports send empty report */
+			req->buf = hidg->get_report.data;
+			memset(req->buf, 0x0, req->length);
+		}
+
+		status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+	}
+
+	if (status < 0)
+		VDBG(cdev, "usb_ep_queue error on ep0 responding to GET_REPORT\n");
+}
+
+static int f_hidg_get_report_id(struct file *file, __u8 __user *buffer)
+{
+	struct f_hidg			*hidg = file->private_data;
+	int ret = 0;
+
+	ret = put_user(hidg->get_report_req_report_id, buffer);
+
+	return ret;
+}
+
+static int f_hidg_get_report(struct file *file, struct usb_hidg_report __user *buffer)
+{
+	struct f_hidg			*hidg = file->private_data;
+	struct usb_composite_dev	*cdev = hidg->func.config->cdev;
+	unsigned long	flags;
+	struct report_entry *entry;
+	struct report_entry *ptr;
+	__u8 report_id;
+
+	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	if (copy_from_user(&entry->report_data, buffer,
+				sizeof(struct usb_hidg_report))) {
+		ERROR(cdev, "copy_from_user error\n");
+		kfree(entry);
+		return -EINVAL;
+	}
+
+	report_id = entry->report_data.report_id;
+
+	spin_lock_irqsave(&hidg->get_report_spinlock, flags);
+	ptr = f_hidg_search_for_report(hidg, report_id);
+
+	if (ptr) {
+		/* Report already exists in list - update it */
+		if (copy_from_user(&ptr->report_data, buffer,
+				sizeof(struct usb_hidg_report))) {
+			spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+			ERROR(cdev, "copy_from_user error\n");
+			kfree(entry);
+			return -EINVAL;
+		}
+		kfree(entry);
+	} else {
+		/* Report does not exist in list - add it */
+		list_add_tail(&entry->node, &hidg->report_list);
+	}
+
+	/* If there is no response pending then do nothing further */
+	if (hidg->get_report_returned) {
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+		return 0;
+	}
+
+	/* If this userspace response serves the current pending report */
+	if (hidg->get_report_req_report_id == report_id) {
+		hidg->get_report_returned = true;
+		wake_up(&hidg->get_queue);
+	}
+
+	spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+	return 0;
+}
+
+static long f_hidg_ioctl(struct file *file, unsigned int code, unsigned long arg)
+{
+	switch (code) {
+	case GADGET_HID_READ_GET_REPORT_ID:
+		return f_hidg_get_report_id(file, (__u8 __user *)arg);
+	case GADGET_HID_WRITE_GET_REPORT:
+		return f_hidg_get_report(file, (struct usb_hidg_report __user *)arg);
+	default:
+		return -ENOTTY;
+	}
+}
+
+static __poll_t f_hidg_poll(struct file *file, poll_table *wait)
 {
 	struct f_hidg	*hidg  = file->private_data;
-	unsigned int	ret = 0;
+	__poll_t	ret = 0;
 
 	poll_wait(file, &hidg->read_queue, wait);
 	poll_wait(file, &hidg->write_queue, wait);
+	poll_wait(file, &hidg->get_queue, wait);
+	poll_wait(file, &hidg->get_id_queue, wait);
 
 	if (WRITE_COND)
-		ret |= POLLOUT | POLLWRNORM;
+		ret |= EPOLLOUT | EPOLLWRNORM;
 
-	if (READ_COND)
-		ret |= POLLIN | POLLRDNORM;
+	if (hidg->use_out_ep) {
+		if (READ_COND_INTOUT)
+			ret |= EPOLLIN | EPOLLRDNORM;
+	} else {
+		if (READ_COND_SSREPORT)
+			ret |= EPOLLIN | EPOLLRDNORM;
+	}
+
+	if (GET_REPORT_COND)
+		ret |= EPOLLPRI;
 
 	return ret;
 }
 
 #undef WRITE_COND
-#undef READ_COND
+#undef READ_COND_SSREPORT
+#undef READ_COND_INTOUT
+#undef GET_REPORT_COND
 
 static int f_hidg_release(struct inode *inode, struct file *fd)
 {
@@ -461,7 +766,7 @@ static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
 	return alloc_ep_req(ep, length);
 }
 
-static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
+static void hidg_intout_complete(struct usb_ep *ep, struct usb_request *req)
 {
 	struct f_hidg *hidg = (struct f_hidg *) req->context;
 	struct usb_composite_dev *cdev = hidg->func.config->cdev;
@@ -486,7 +791,7 @@ static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
 		break;
 	default:
 		ERROR(cdev, "Set report failed %d\n", req->status);
-		/* FALLTHROUGH */
+		fallthrough;
 	case -ECONNABORTED:		/* hardware forced ep reset */
 	case -ECONNRESET:		/* request dequeued */
 	case -ESHUTDOWN:		/* disconnect from host */
@@ -496,6 +801,41 @@ free_req:
 	}
 }
 
+static void hidg_ssreport_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct f_hidg *hidg = (struct f_hidg *)req->context;
+	struct usb_composite_dev *cdev = hidg->func.config->cdev;
+	char *new_buf = NULL;
+	unsigned long flags;
+
+	if (req->status != 0 || req->buf == NULL || req->actual == 0) {
+		ERROR(cdev,
+		      "%s FAILED: status=%d, buf=%p, actual=%d\n",
+		      __func__, req->status, req->buf, req->actual);
+		return;
+	}
+
+	spin_lock_irqsave(&hidg->read_spinlock, flags);
+
+	new_buf = krealloc(hidg->set_report_buf, req->actual, GFP_ATOMIC);
+	if (new_buf == NULL) {
+		spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+		return;
+	}
+	hidg->set_report_buf = new_buf;
+
+	hidg->set_report_length = req->actual;
+	memcpy(hidg->set_report_buf, req->buf, req->actual);
+
+	spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
+	wake_up(&hidg->read_queue);
+}
+
+static void hidg_get_report_complete(struct usb_ep *ep, struct usb_request *req)
+{
+}
+
 static int hidg_setup(struct usb_function *f,
 		const struct usb_ctrlrequest *ctrl)
 {
@@ -504,6 +844,7 @@ static int hidg_setup(struct usb_function *f,
 	struct usb_request		*req  = cdev->req;
 	int status = 0;
 	__u16 value, length;
+	unsigned long	flags;
 
 	value	= __le16_to_cpu(ctrl->wValue);
 	length	= __le16_to_cpu(ctrl->wLength);
@@ -515,33 +856,72 @@ static int hidg_setup(struct usb_function *f,
 	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 		  | HID_REQ_GET_REPORT):
-		VDBG(cdev, "get_report\n");
+		VDBG(cdev, "get_report | wLength=%d\n", ctrl->wLength);
 
-		/* send an empty report */
-		length = min_t(unsigned, length, hidg->report_length);
-		memset(req->buf, 0x0, length);
+		/*
+		 * Update GET_REPORT ID so that an ioctl can be used to determine what
+		 * GET_REPORT the request was actually for.
+		 */
+		spin_lock_irqsave(&hidg->get_report_spinlock, flags);
+		hidg->get_report_req_report_id = value & 0xff;
+		hidg->get_report_req_report_length = length;
+		spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
 
-		goto respond;
-		break;
+		queue_work(hidg->workqueue, &hidg->work);
+
+		return status;
 
 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 		  | HID_REQ_GET_PROTOCOL):
 		VDBG(cdev, "get_protocol\n");
-		goto stall;
+		length = min_t(unsigned int, length, 1);
+		((u8 *) req->buf)[0] = hidg->protocol;
+		goto respond;
+		break;
+
+	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+		  | HID_REQ_GET_IDLE):
+		VDBG(cdev, "get_idle\n");
+		length = min_t(unsigned int, length, 1);
+		((u8 *) req->buf)[0] = hidg->idle;
+		goto respond;
 		break;
 
 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 		  | HID_REQ_SET_REPORT):
 		VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
-		goto stall;
+		if (hidg->use_out_ep)
+			goto stall;
+		req->complete = hidg_ssreport_complete;
+		req->context  = hidg;
+		goto respond;
 		break;
 
 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 		  | HID_REQ_SET_PROTOCOL):
 		VDBG(cdev, "set_protocol\n");
+		if (value > HID_REPORT_PROTOCOL)
+			goto stall;
+		length = 0;
+		/*
+		 * We assume that programs implementing the Boot protocol
+		 * are also compatible with the Report Protocol
+		 */
+		if (hidg->bInterfaceSubClass == USB_INTERFACE_SUBCLASS_BOOT) {
+			hidg->protocol = value;
+			goto respond;
+		}
 		goto stall;
 		break;
 
+	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+		  | HID_REQ_SET_IDLE):
+		VDBG(cdev, "set_idle\n");
+		length = 0;
+		hidg->idle = value >> 8;
+		goto respond;
+		break;
+
 	case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
 		  | USB_REQ_GET_DESCRIPTOR):
 		switch (value >> 8) {
@@ -550,8 +930,8 @@ static int hidg_setup(struct usb_function *f,
 			struct hid_descriptor hidg_desc_copy = hidg_desc;
 
 			VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
-			hidg_desc_copy.desc[0].bDescriptorType = HID_DT_REPORT;
-			hidg_desc_copy.desc[0].wDescriptorLength =
+			hidg_desc_copy.rpt_desc.bDescriptorType = HID_DT_REPORT;
+			hidg_desc_copy.rpt_desc.wDescriptorLength =
 				cpu_to_le16(hidg->report_desc_length);
 
 			length = min_t(unsigned short, length,
@@ -587,7 +967,7 @@ stall:
 	return -EOPNOTSUPP;
 
 respond:
-	req->zero = 0;
+	req->zero = 1;
 	req->length = length;
 	status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 	if (status < 0)
@@ -602,15 +982,31 @@ static void hidg_disable(struct usb_function *f)
 	unsigned long flags;
 
 	usb_ep_disable(hidg->in_ep);
-	usb_ep_disable(hidg->out_ep);
 
-	spin_lock_irqsave(&hidg->read_spinlock, flags);
-	list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
-		free_ep_req(hidg->out_ep, list->req);
-		list_del(&list->list);
-		kfree(list);
+	if (hidg->out_ep) {
+		usb_ep_disable(hidg->out_ep);
+
+		spin_lock_irqsave(&hidg->read_spinlock, flags);
+		list_for_each_entry_safe(list, next, &hidg->completed_out_req, list) {
+			free_ep_req(hidg->out_ep, list->req);
+			list_del(&list->list);
+			kfree(list);
+		}
+		spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+	}
+
+	spin_lock_irqsave(&hidg->get_report_spinlock, flags);
+	if (!hidg->get_report_returned) {
+		usb_ep_free_request(f->config->cdev->gadget->ep0, hidg->get_req);
+		hidg->get_req = NULL;
+		hidg->get_report_returned = true;
 	}
+	spin_unlock_irqrestore(&hidg->get_report_spinlock, flags);
+
+	spin_lock_irqsave(&hidg->read_spinlock, flags);
+	hidg->disabled = true;
 	spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+	wake_up(&hidg->read_queue);
 
 	spin_lock_irqsave(&hidg->write_spinlock, flags);
 	if (!hidg->write_pending) {
@@ -656,8 +1052,7 @@ static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 		}
 	}
 
-
-	if (hidg->out_ep != NULL) {
+	if (hidg->use_out_ep && hidg->out_ep != NULL) {
 		/* restart endpoint */
 		usb_ep_disable(hidg->out_ep);
 
@@ -682,7 +1077,7 @@ static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 					hidg_alloc_ep_req(hidg->out_ep,
 							  hidg->report_length);
 			if (req) {
-				req->complete = hidg_set_report_complete;
+				req->complete = hidg_intout_complete;
 				req->context  = hidg;
 				status = usb_ep_queue(hidg->out_ep, req,
 						      GFP_ATOMIC);
@@ -698,6 +1093,10 @@ static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 		}
 	}
 
+	spin_lock_irqsave(&hidg->read_spinlock, flags);
+	hidg->disabled = false;
+	spin_unlock_irqrestore(&hidg->read_spinlock, flags);
+
 	if (hidg->in_ep != NULL) {
 		spin_lock_irqsave(&hidg->write_spinlock, flags);
 		hidg->req = req_in;
@@ -708,7 +1107,8 @@ static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 	}
 	return 0;
 disable_out_ep:
-	usb_ep_disable(hidg->out_ep);
+	if (hidg->out_ep)
+		usb_ep_disable(hidg->out_ep);
 free_req_in:
 	if (req_in)
 		free_ep_req(hidg->in_ep, req_in);
@@ -721,6 +1121,14 @@ fail:
 	return status;
 }
 
+#ifdef CONFIG_COMPAT
+static long f_hidg_compat_ioctl(struct file *file, unsigned int code,
+		unsigned long value)
+{
+	return f_hidg_ioctl(file, code, value);
+}
+#endif
+
 static const struct file_operations f_hidg_fops = {
 	.owner		= THIS_MODULE,
 	.open		= f_hidg_open,
@@ -728,6 +1136,10 @@ static const struct file_operations f_hidg_fops = {
 	.write		= f_hidg_write,
 	.read		= f_hidg_read,
 	.poll		= f_hidg_poll,
+	.unlocked_ioctl	= f_hidg_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = f_hidg_compat_ioctl,
+#endif
 	.llseek		= noop_llseek,
 };
 
@@ -736,9 +1148,16 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	struct usb_ep		*ep;
 	struct f_hidg		*hidg = func_to_hidg(f);
 	struct usb_string	*us;
-	struct device		*device;
 	int			status;
-	dev_t			dev;
+
+	hidg->get_req = usb_ep_alloc_request(c->cdev->gadget->ep0, GFP_ATOMIC);
+	if (!hidg->get_req)
+		return -ENOMEM;
+
+	hidg->get_req->zero = 0;
+	hidg->get_req->complete = hidg_get_report_complete;
+	hidg->get_req->context = hidg;
+	hidg->get_report_returned = true;
 
 	/* maybe allocate device-global string IDs, and patch descriptors */
 	us = usb_gstrings_attach(c->cdev, ct_func_strings,
@@ -760,20 +1179,39 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 		goto fail;
 	hidg->in_ep = ep;
 
-	ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
-	if (!ep)
-		goto fail;
-	hidg->out_ep = ep;
+	hidg->out_ep = NULL;
+	if (hidg->use_out_ep) {
+		ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_out_ep_desc);
+		if (!ep)
+			goto fail;
+		hidg->out_ep = ep;
+	}
+
+	/* used only if use_out_ep == 1 */
+	hidg->set_report_buf = NULL;
 
 	/* set descriptor dynamic values */
 	hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
 	hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
+	hidg_interface_desc.bNumEndpoints = hidg->use_out_ep ? 2 : 1;
+	hidg->protocol = HID_REPORT_PROTOCOL;
+	hidg->idle = 1;
 	hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 	hidg_ss_in_comp_desc.wBytesPerInterval =
 				cpu_to_le16(hidg->report_length);
 	hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 	hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 	hidg_ss_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
+
+	/* IN endpoints: FS default=10ms, HS default=4µ-frame; user override if set */
+	if (!hidg->interval_user_set) {
+		hidg_fs_in_ep_desc.bInterval = 10;
+		hidg_hs_in_ep_desc.bInterval = 4;
+	} else {
+		hidg_fs_in_ep_desc.bInterval = hidg->interval;
+		hidg_hs_in_ep_desc.bInterval = hidg->interval;
+	}
+
 	hidg_ss_out_comp_desc.wBytesPerInterval =
 				cpu_to_le16(hidg->report_length);
 	hidg_hs_out_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
@@ -782,8 +1220,8 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	 * We can use hidg_desc struct here but we should not relay
 	 * that its content won't change after returning from this function.
 	 */
-	hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
-	hidg_desc.desc[0].wDescriptorLength =
+	hidg_desc.rpt_desc.bDescriptorType = HID_DT_REPORT;
+	hidg_desc.rpt_desc.wDescriptorLength =
 		cpu_to_le16(hidg->report_desc_length);
 
 	hidg_hs_in_ep_desc.bEndpointAddress =
@@ -796,8 +1234,27 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	hidg_ss_out_ep_desc.bEndpointAddress =
 		hidg_fs_out_ep_desc.bEndpointAddress;
 
-	status = usb_assign_descriptors(f, hidg_fs_descriptors,
-			hidg_hs_descriptors, hidg_ss_descriptors, NULL);
+	if (hidg->use_out_ep) {
+		/* OUT endpoints: same defaults (FS=10, HS=4) unless user set */
+		if (!hidg->interval_user_set) {
+			hidg_fs_out_ep_desc.bInterval = 10;
+			hidg_hs_out_ep_desc.bInterval = 4;
+		} else {
+			hidg_fs_out_ep_desc.bInterval = hidg->interval;
+			hidg_hs_out_ep_desc.bInterval = hidg->interval;
+		}
+		status = usb_assign_descriptors(f,
+			    hidg_fs_descriptors_intout,
+			    hidg_hs_descriptors_intout,
+			    hidg_ss_descriptors_intout,
+			    hidg_ss_descriptors_intout);
+	} else {
+		status = usb_assign_descriptors(f,
+			hidg_fs_descriptors_ssreport,
+			hidg_hs_descriptors_ssreport,
+			hidg_ss_descriptors_ssreport,
+			hidg_ss_descriptors_ssreport);
+	}
 	if (status)
 		goto fail;
 
@@ -805,27 +1262,33 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	hidg->write_pending = 1;
 	hidg->req = NULL;
 	spin_lock_init(&hidg->read_spinlock);
+	spin_lock_init(&hidg->get_report_spinlock);
 	init_waitqueue_head(&hidg->write_queue);
 	init_waitqueue_head(&hidg->read_queue);
+	init_waitqueue_head(&hidg->get_queue);
+	init_waitqueue_head(&hidg->get_id_queue);
 	INIT_LIST_HEAD(&hidg->completed_out_req);
+	INIT_LIST_HEAD(&hidg->report_list);
+
+	INIT_WORK(&hidg->work, get_report_workqueue_handler);
+	hidg->workqueue = alloc_workqueue("report_work",
+					  WQ_FREEZABLE | WQ_MEM_RECLAIM | WQ_PERCPU,
+					  1);
+
+	if (!hidg->workqueue) {
+		status = -ENOMEM;
+		goto fail_free_descs;
+	}
 
 	/* create char device */
 	cdev_init(&hidg->cdev, &f_hidg_fops);
-	dev = MKDEV(major, hidg->minor);
-	status = cdev_add(&hidg->cdev, dev, 1);
+	status = cdev_device_add(&hidg->cdev, &hidg->dev);
 	if (status)
-		goto fail_free_descs;
-
-	device = device_create(hidg_class, NULL, dev, NULL,
-			       "%s%d", "hidg", hidg->minor);
-	if (IS_ERR(device)) {
-		status = PTR_ERR(device);
-		goto del;
-	}
+		goto fail_free_all;
 
 	return 0;
-del:
-	cdev_del(&hidg->cdev);
+fail_free_all:
+	destroy_workqueue(hidg->workqueue);
 fail_free_descs:
 	usb_free_all_descriptors(f);
 fail:
@@ -833,6 +1296,9 @@ fail:
 	if (hidg->req != NULL)
 		free_ep_req(hidg->in_ep, hidg->req);
 
+	usb_ep_free_request(c->cdev->gadget->ep0, hidg->get_req);
+	hidg->get_req = NULL;
+
 	return status;
 }
 
@@ -840,9 +1306,9 @@ static inline int hidg_get_minor(void)
 {
 	int ret;
 
-	ret = ida_simple_get(&hidg_ida, 0, 0, GFP_KERNEL);
+	ret = ida_alloc(&hidg_ida, GFP_KERNEL);
 	if (ret >= HIDG_MINORS) {
-		ida_simple_remove(&hidg_ida, ret);
+		ida_free(&hidg_ida, ret);
 		ret = -ENODEV;
 	}
 
@@ -912,6 +1378,7 @@ CONFIGFS_ATTR(f_hid_opts_, name)
 
 F_HID_OPT(subclass, 8, 255);
 F_HID_OPT(protocol, 8, 255);
+F_HID_OPT(no_out_endpoint, 8, 1);
 F_HID_OPT(report_length, 16, 65535);
 
 static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page)
@@ -959,6 +1426,53 @@ end:
 
 CONFIGFS_ATTR(f_hid_opts_, report_desc);
 
+static ssize_t f_hid_opts_interval_show(struct config_item *item, char *page)
+{
+	struct f_hid_opts *opts = to_f_hid_opts(item);
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d\n", opts->interval);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_hid_opts_interval_store(struct config_item *item,
+		const char *page, size_t len)
+{
+	struct f_hid_opts *opts = to_f_hid_opts(item);
+	int ret;
+	unsigned int tmp;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	/* parse into a wider type first */
+	ret = kstrtouint(page, 0, &tmp);
+	if (ret)
+		goto end;
+
+	/* range-check against unsigned char max */
+	if (tmp > 255) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->interval = (unsigned char)tmp;
+	opts->interval_user_set = true;
+	ret = len;
+
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+CONFIGFS_ATTR(f_hid_opts_, interval);
+
 static ssize_t f_hid_opts_dev_show(struct config_item *item, char *page)
 {
 	struct f_hid_opts *opts = to_f_hid_opts(item);
@@ -971,13 +1485,15 @@ CONFIGFS_ATTR_RO(f_hid_opts_, dev);
 static struct configfs_attribute *hid_attrs[] = {
 	&f_hid_opts_attr_subclass,
 	&f_hid_opts_attr_protocol,
+	&f_hid_opts_attr_no_out_endpoint,
 	&f_hid_opts_attr_report_length,
+	&f_hid_opts_attr_interval,
 	&f_hid_opts_attr_report_desc,
 	&f_hid_opts_attr_dev,
 	NULL,
 };
 
-static struct config_item_type hid_func_type = {
+static const struct config_item_type hid_func_type = {
 	.ct_item_ops	= &hidg_item_ops,
 	.ct_attrs	= hid_attrs,
 	.ct_owner	= THIS_MODULE,
@@ -985,7 +1501,7 @@ static struct config_item_type hid_func_type = {
 
 static inline void hidg_put_minor(int minor)
 {
-	ida_simple_remove(&hidg_ida, minor);
+	ida_free(&hidg_ida, minor);
 }
 
 static void hidg_free_inst(struct usb_function_instance *f)
@@ -1018,6 +1534,10 @@ static struct usb_function_instance *hidg_alloc_inst(void)
 	if (!opts)
 		return ERR_PTR(-ENOMEM);
 	mutex_init(&opts->lock);
+
+	opts->interval = 4;
+	opts->interval_user_set = false;
+
 	opts->func_inst.free_func_inst = hidg_free_inst;
 	ret = &opts->func_inst;
 
@@ -1054,8 +1574,7 @@ static void hidg_free(struct usb_function *f)
 
 	hidg = func_to_hidg(f);
 	opts = container_of(f->fi, struct f_hid_opts, func_inst);
-	kfree(hidg->report_desc);
-	kfree(hidg);
+	put_device(&hidg->dev);
 	mutex_lock(&opts->lock);
 	--opts->refcnt;
 	mutex_unlock(&opts->lock);
@@ -1065,9 +1584,8 @@ static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct f_hidg *hidg = func_to_hidg(f);
 
-	device_destroy(hidg_class, MKDEV(major, hidg->minor));
-	cdev_del(&hidg->cdev);
-
+	cdev_device_del(&hidg->cdev, &hidg->dev);
+	destroy_workqueue(hidg->workqueue);
 	usb_free_all_descriptors(f);
 }
 
@@ -1075,6 +1593,7 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
 {
 	struct f_hidg *hidg;
 	struct f_hid_opts *opts;
+	int ret;
 
 	/* allocate and initialize one new instance */
 	hidg = kzalloc(sizeof(*hidg), GFP_KERNEL);
@@ -1084,24 +1603,33 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
 	opts = container_of(fi, struct f_hid_opts, func_inst);
 
 	mutex_lock(&opts->lock);
-	++opts->refcnt;
 
-	hidg->minor = opts->minor;
+	device_initialize(&hidg->dev);
+	hidg->dev.release = hidg_release;
+	hidg->dev.class = &hidg_class;
+	hidg->dev.devt = MKDEV(major, opts->minor);
+	ret = dev_set_name(&hidg->dev, "hidg%d", opts->minor);
+	if (ret)
+		goto err_unlock;
+
 	hidg->bInterfaceSubClass = opts->subclass;
 	hidg->bInterfaceProtocol = opts->protocol;
 	hidg->report_length = opts->report_length;
 	hidg->report_desc_length = opts->report_desc_length;
+	hidg->interval = opts->interval;
+	hidg->interval_user_set = opts->interval_user_set;
 	if (opts->report_desc) {
 		hidg->report_desc = kmemdup(opts->report_desc,
 					    opts->report_desc_length,
 					    GFP_KERNEL);
 		if (!hidg->report_desc) {
-			kfree(hidg);
-			mutex_unlock(&opts->lock);
-			return ERR_PTR(-ENOMEM);
+			ret = -ENOMEM;
+			goto err_put_device;
 		}
 	}
+	hidg->use_out_ep = !opts->no_out_endpoint;
 
+	++opts->refcnt;
 	mutex_unlock(&opts->lock);
 
 	hidg->func.name    = "hid";
@@ -1112,13 +1640,20 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
 	hidg->func.setup   = hidg_setup;
 	hidg->func.free_func = hidg_free;
 
-	/* this could me made configurable at some point */
+	/* this could be made configurable at some point */
 	hidg->qlen	   = 4;
 
 	return &hidg->func;
+
+err_put_device:
+	put_device(&hidg->dev);
+err_unlock:
+	mutex_unlock(&opts->lock);
+	return ERR_PTR(ret);
 }
 
 DECLARE_USB_FUNCTION_INIT(hid, hidg_alloc_inst, hidg_alloc);
+MODULE_DESCRIPTION("USB HID function driver");
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Fabien Chouteau");
 
@@ -1127,17 +1662,13 @@ int ghid_setup(struct usb_gadget *g, int count)
 	int status;
 	dev_t dev;
 
-	hidg_class = class_create(THIS_MODULE, "hidg");
-	if (IS_ERR(hidg_class)) {
-		status = PTR_ERR(hidg_class);
-		hidg_class = NULL;
+	status = class_register(&hidg_class);
+	if (status)
 		return status;
-	}
 
 	status = alloc_chrdev_region(&dev, 0, count, "hidg");
 	if (status) {
-		class_destroy(hidg_class);
-		hidg_class = NULL;
+		class_unregister(&hidg_class);
 		return status;
 	}
 
@@ -1154,6 +1685,5 @@ void ghid_cleanup(void)
 		major = minors = 0;
 	}
 
-	class_destroy(hidg_class);
-	hidg_class = NULL;
+	class_unregister(&hidg_class);
 }