/*
   * Roccat Kone driver for Linux
   *
   * Copyright (c) 2010 Stefan Achatz <erazor_de@users.sourceforge.net>
   */
  
  /*
   * 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.
   */
  
  /*
   * Roccat Kone is a gamer mouse which consists of a mouse part and a keyboard
   * part. The keyboard part enables the mouse to execute stored macros with mixed
   * key- and button-events.
   *
   * TODO implement on-the-fly polling-rate change
   *      The windows driver has the ability to change the polling rate of the
   *      device on the press of a mousebutton.
   *      Is it possible to remove and reinstall the urb in raw-event- or any
   *      other handler, or to defer this action to be executed somewhere else?
   *
   * TODO is it possible to overwrite group for sysfs attributes via udev?
   */
  
  #include <linux/device.h>
  #include <linux/input.h>
  #include <linux/hid.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/hid-roccat.h>
  #include "hid-ids.h"
  #include "hid-roccat-common.h"
  #include "hid-roccat-kone.h"
  
  static uint profile_numbers[5] = {0, 1, 2, 3, 4};
  
  static void kone_profile_activated(struct kone_device *kone, uint new_profile)
  {
  	kone->actual_profile = new_profile;
  	kone->actual_dpi = kone->profiles[new_profile - 1].startup_dpi;
  }
  
  static void kone_profile_report(struct kone_device *kone, uint new_profile)
  {
  	struct kone_roccat_report roccat_report;
  	roccat_report.event = kone_mouse_event_switch_profile;
  	roccat_report.value = new_profile;
  	roccat_report.key = 0;
  	roccat_report_event(kone->chrdev_minor, (uint8_t *)&roccat_report);
  }
  
  static int kone_receive(struct usb_device *usb_dev, uint usb_command,
  		void *data, uint size)
  {
  	char *buf;
  	int len;
  
  	buf = kmalloc(size, GFP_KERNEL);
  	if (buf == NULL)
  		return -ENOMEM;
  
  	len = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
  			HID_REQ_GET_REPORT,
  			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
  			usb_command, 0, buf, size, USB_CTRL_SET_TIMEOUT);
  
  	memcpy(data, buf, size);
  	kfree(buf);
  	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
  }
  
  static int kone_send(struct usb_device *usb_dev, uint usb_command,
  		void const *data, uint size)
  {
  	char *buf;
  	int len;
  
  	buf = kmemdup(data, size, GFP_KERNEL);
  	if (buf == NULL)
  		return -ENOMEM;
  
  	len = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
  			HID_REQ_SET_REPORT,
  			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
  			usb_command, 0, buf, size, USB_CTRL_SET_TIMEOUT);
  
  	kfree(buf);
  	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
  }
  
  /* kone_class is used for creating sysfs attributes via roccat char device */
  static struct class *kone_class;
  
  static void kone_set_settings_checksum(struct kone_settings *settings)
  {
  	uint16_t checksum = 0;
  	unsigned char *address = (unsigned char *)settings;
  	int i;
  
  	for (i = 0; i < sizeof(struct kone_settings) - 2; ++i, ++address)
  		checksum += *address;
  	settings->checksum = cpu_to_le16(checksum);
  }
  
  /*
   * Checks success after writing data to mouse
   * On success returns 0
   * On failure returns errno
   */
  static int kone_check_write(struct usb_device *usb_dev)
  {
  	int retval;
  	uint8_t data;
  
  	do {
  		/*
  		 * Mouse needs 50 msecs until it says ok, but there are
  		 * 30 more msecs needed for next write to work.
  		 */
  		msleep(80);
  
  		retval = kone_receive(usb_dev,
  				kone_command_confirm_write, &data, 1);
  		if (retval)
  			return retval;
  
  		/*
  		 * value of 3 seems to mean something like
  		 * "not finished yet, but it looks good"
  		 * So check again after a moment.
  		 */
  	} while (data == 3);
  
  	if (data == 1) /* everything alright */
  		return 0;
  
  	/* unknown answer */
  	dev_err(&usb_dev->dev, "got retval %d when checking write
  ", data);
  	return -EIO;
  }
  
  /*
   * Reads settings from mouse and stores it in @buf
   * On success returns 0
   * On failure returns errno
   */
  static int kone_get_settings(struct usb_device *usb_dev,
  		struct kone_settings *buf)
  {
  	return kone_receive(usb_dev, kone_command_settings, buf,
  			sizeof(struct kone_settings));
  }
  
  /*
   * Writes settings from @buf to mouse
   * On success returns 0
   * On failure returns errno
   */
  static int kone_set_settings(struct usb_device *usb_dev,
  		struct kone_settings const *settings)
  {
  	int retval;
  	retval = kone_send(usb_dev, kone_command_settings,
  			settings, sizeof(struct kone_settings));
  	if (retval)
  		return retval;
  	return kone_check_write(usb_dev);
  }
  
  /*
   * Reads profile data from mouse and stores it in @buf
   * @number: profile number to read
   * On success returns 0
   * On failure returns errno
   */
  static int kone_get_profile(struct usb_device *usb_dev,
  		struct kone_profile *buf, int number)
  {
  	int len;
  
  	if (number < 1 || number > 5)
  		return -EINVAL;
  
  	len = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
  			USB_REQ_CLEAR_FEATURE,
  			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
  			kone_command_profile, number, buf,
  			sizeof(struct kone_profile), USB_CTRL_SET_TIMEOUT);
  
  	if (len != sizeof(struct kone_profile))
  		return -EIO;
  
  	return 0;
  }
  
  /*
   * Writes profile data to mouse.
   * @number: profile number to write
   * On success returns 0
   * On failure returns errno
   */
  static int kone_set_profile(struct usb_device *usb_dev,
  		struct kone_profile const *profile, int number)
  {
  	int len;
  
  	if (number < 1 || number > 5)
  		return -EINVAL;
  
  	len = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
  			USB_REQ_SET_CONFIGURATION,
  			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
  			kone_command_profile, number, (void *)profile,
  			sizeof(struct kone_profile),
  			USB_CTRL_SET_TIMEOUT);
  
  	if (len != sizeof(struct kone_profile))
  		return len;
  
  	if (kone_check_write(usb_dev))
  		return -EIO;
  
  	return 0;
  }
  
  /*
   * Reads value of "fast-clip-weight" and stores it in @result
   * On success returns 0
   * On failure returns errno
   */
  static int kone_get_weight(struct usb_device *usb_dev, int *result)
  {
  	int retval;
  	uint8_t data;
  
  	retval = kone_receive(usb_dev, kone_command_weight, &data, 1);
  
  	if (retval)
  		return retval;
  
  	*result = (int)data;
  	return 0;
  }
  
  /*
   * Reads firmware_version of mouse and stores it in @result
   * On success returns 0
   * On failure returns errno
   */
  static int kone_get_firmware_version(struct usb_device *usb_dev, int *result)
  {
  	int retval;
  	uint16_t data;
  
  	retval = kone_receive(usb_dev, kone_command_firmware_version,
  			&data, 2);
  	if (retval)
  		return retval;
  
  	*result = le16_to_cpu(data);
  	return 0;
  }
  
  static ssize_t kone_sysfs_read_settings(struct file *fp, struct kobject *kobj,
  		struct bin_attribute *attr, char *buf,
  		loff_t off, size_t count) {
  	struct device *dev =
  			container_of(kobj, struct device, kobj)->parent->parent;
  	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
  
  	if (off >= sizeof(struct kone_settings))
  		return 0;
  
  	if (off + count > sizeof(struct kone_settings))
  		count = sizeof(struct kone_settings) - off;
  
  	mutex_lock(&kone->kone_lock);
  	memcpy(buf, ((char const *)&kone->settings) + off, count);
  	mutex_unlock(&kone->kone_lock);
  
  	return count;
  }
  
  /*
   * Writing settings automatically activates startup_profile.
   * This function keeps values in kone_device up to date and assumes that in
   * case of error the old data is still valid
   */
  static ssize_t kone_sysfs_write_settings(struct file *fp, struct kobject *kobj,
  		struct bin_attribute *attr, char *buf,
  		loff_t off, size_t count) {
  	struct device *dev =
  			container_of(kobj, struct device, kobj)->parent->parent;
  	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
  	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
  	int retval = 0, difference, old_profile;
  
  	/* I need to get my data in one piece */
  	if (off != 0 || count != sizeof(struct kone_settings))
  		return -EINVAL;
  
  	mutex_lock(&kone->kone_lock);
  	difference = memcmp(buf, &kone->settings, sizeof(struct kone_settings));
  	if (difference) {
  		retval = kone_set_settings(usb_dev,
  				(struct kone_settings const *)buf);
  		if (retval) {
  			mutex_unlock(&kone->kone_lock);
  			return retval;
  		}
  
  		old_profile = kone->settings.startup_profile;
  		memcpy(&kone->settings, buf, sizeof(struct kone_settings));
  
  		kone_profile_activated(kone, kone->settings.startup_profile);
  
  		if (kone->settings.startup_profile != old_profile)
  			kone_profile_report(kone, kone->settings.startup_profile);
  	}
  	mutex_unlock(&kone->kone_lock);
  
  	return sizeof(struct kone_settings);
  }
  static BIN_ATTR(settings, 0660, kone_sysfs_read_settings,
  		kone_sysfs_write_settings, sizeof(struct kone_settings));
  
  static ssize_t kone_sysfs_read_profilex(struct file *fp,
  		struct kobject *kobj, struct bin_attribute *attr,
  		char *buf, loff_t off, size_t count) {
  	struct device *dev =
  			container_of(kobj, struct device, kobj)->parent->parent;
  	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
  
  	if (off >= sizeof(struct kone_profile))
  		return 0;
  
  	if (off + count > sizeof(struct kone_profile))
  		count = sizeof(struct kone_profile) - off;
  
  	mutex_lock(&kone->kone_lock);
  	memcpy(buf, ((char const *)&kone->profiles[*(uint *)(attr->private)]) + off, count);
  	mutex_unlock(&kone->kone_lock);
  
  	return count;
  }
  
  /* Writes data only if different to stored data */
  static ssize_t kone_sysfs_write_profilex(struct file *fp,
  		struct kobject *kobj, struct bin_attribute *attr,
  		char *buf, loff_t off, size_t count) {
  	struct device *dev =
  			container_of(kobj, struct device, kobj)->parent->parent;
  	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
  	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
  	struct kone_profile *profile;
  	int retval = 0, difference;
  
  	/* I need to get my data in one piece */
  	if (off != 0 || count != sizeof(struct kone_profile))
  		return -EINVAL;
  
  	profile = &kone->profiles[*(uint *)(attr->private)];
  
  	mutex_lock(&kone->kone_lock);
  	difference = memcmp(buf, profile, sizeof(struct kone_profile));
  	if (difference) {
  		retval = kone_set_profile(usb_dev,
  				(struct kone_profile const *)buf,
  				*(uint *)(attr->private) + 1);
  		if (!retval)
  			memcpy(profile, buf, sizeof(struct kone_profile));
  	}
  	mutex_unlock(&kone->kone_lock);
  
  	if (retval)
  		return retval;
  
  	return sizeof(struct kone_profile);
  }
  #define PROFILE_ATTR(number)					\
  static struct bin_attribute bin_attr_profile##number = {	\
  	.attr = { .name = "profile" #number, .mode = 0660 },	\
  	.size = sizeof(struct kone_profile),			\
  	.read = kone_sysfs_read_profilex,			\
  	.write = kone_sysfs_write_profilex,			\
  	.private = &profile_numbers[number-1],			\
  };
  PROFILE_ATTR(1);
  PROFILE_ATTR(2);
  PROFILE_ATTR(3);
  PROFILE_ATTR(4);
  PROFILE_ATTR(5);
  
  static ssize_t kone_sysfs_show_actual_profile(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone =
  			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
  	return snprintf(buf, PAGE_SIZE, "%d
  ", kone->actual_profile);
  }
  static DEVICE_ATTR(actual_profile, 0440, kone_sysfs_show_actual_profile, NULL);
  
  static ssize_t kone_sysfs_show_actual_dpi(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone =
  			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
  	return snprintf(buf, PAGE_SIZE, "%d
  ", kone->actual_dpi);
  }
  static DEVICE_ATTR(actual_dpi, 0440, kone_sysfs_show_actual_dpi, NULL);
  
  /* weight is read each time, since we don't get informed when it's changed */
  static ssize_t kone_sysfs_show_weight(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone;
  	struct usb_device *usb_dev;
  	int weight = 0;
  	int retval;
  
  	dev = dev->parent->parent;
  	kone = hid_get_drvdata(dev_get_drvdata(dev));
  	usb_dev = interface_to_usbdev(to_usb_interface(dev));
  
  	mutex_lock(&kone->kone_lock);
  	retval = kone_get_weight(usb_dev, &weight);
  	mutex_unlock(&kone->kone_lock);
  
  	if (retval)
  		return retval;
  	return snprintf(buf, PAGE_SIZE, "%d
  ", weight);
  }
  static DEVICE_ATTR(weight, 0440, kone_sysfs_show_weight, NULL);
  
  static ssize_t kone_sysfs_show_firmware_version(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone =
  			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
  	return snprintf(buf, PAGE_SIZE, "%d
  ", kone->firmware_version);
  }
  static DEVICE_ATTR(firmware_version, 0440, kone_sysfs_show_firmware_version,
  		   NULL);
  
  static ssize_t kone_sysfs_show_tcu(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone =
  			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
  	return snprintf(buf, PAGE_SIZE, "%d
  ", kone->settings.tcu);
  }
  
  static int kone_tcu_command(struct usb_device *usb_dev, int number)
  {
  	unsigned char value;
  	value = number;
  	return kone_send(usb_dev, kone_command_calibrate, &value, 1);
  }
  
  /*
   * Calibrating the tcu is the only action that changes settings data inside the
   * mouse, so this data needs to be reread
   */
  static ssize_t kone_sysfs_set_tcu(struct device *dev,
  		struct device_attribute *attr, char const *buf, size_t size)
  {
  	struct kone_device *kone;
  	struct usb_device *usb_dev;
  	int retval;
  	unsigned long state;
  
  	dev = dev->parent->parent;
  	kone = hid_get_drvdata(dev_get_drvdata(dev));
  	usb_dev = interface_to_usbdev(to_usb_interface(dev));
  
  	retval = kstrtoul(buf, 10, &state);
  	if (retval)
  		return retval;
  
  	if (state != 0 && state != 1)
  		return -EINVAL;
  
  	mutex_lock(&kone->kone_lock);
  
  	if (state == 1) { /* state activate */
  		retval = kone_tcu_command(usb_dev, 1);
  		if (retval)
  			goto exit_unlock;
  		retval = kone_tcu_command(usb_dev, 2);
  		if (retval)
  			goto exit_unlock;
  		ssleep(5); /* tcu needs this time for calibration */
  		retval = kone_tcu_command(usb_dev, 3);
  		if (retval)
  			goto exit_unlock;
  		retval = kone_tcu_command(usb_dev, 0);
  		if (retval)
  			goto exit_unlock;
  		retval = kone_tcu_command(usb_dev, 4);
  		if (retval)
  			goto exit_unlock;
  		/*
  		 * Kone needs this time to settle things.
  		 * Reading settings too early will result in invalid data.
  		 * Roccat's driver waits 1 sec, maybe this time could be
  		 * shortened.
  		 */
  		ssleep(1);
  	}
  
  	/* calibration changes values in settings, so reread */
  	retval = kone_get_settings(usb_dev, &kone->settings);
  	if (retval)
  		goto exit_no_settings;
  
  	/* only write settings back if activation state is different */
  	if (kone->settings.tcu != state) {
  		kone->settings.tcu = state;
  		kone_set_settings_checksum(&kone->settings);
  
  		retval = kone_set_settings(usb_dev, &kone->settings);
  		if (retval) {
  			dev_err(&usb_dev->dev, "couldn't set tcu state
  ");
  			/*
  			 * try to reread valid settings into buffer overwriting
  			 * first error code
  			 */
  			retval = kone_get_settings(usb_dev, &kone->settings);
  			if (retval)
  				goto exit_no_settings;
  			goto exit_unlock;
  		}
  		/* calibration resets profile */
  		kone_profile_activated(kone, kone->settings.startup_profile);
  	}
  
  	retval = size;
  exit_no_settings:
  	dev_err(&usb_dev->dev, "couldn't read settings
  ");
  exit_unlock:
  	mutex_unlock(&kone->kone_lock);
  	return retval;
  }
  static DEVICE_ATTR(tcu, 0660, kone_sysfs_show_tcu, kone_sysfs_set_tcu);
  
  static ssize_t kone_sysfs_show_startup_profile(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	struct kone_device *kone =
  			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
  	return snprintf(buf, PAGE_SIZE, "%d
  ", kone->settings.startup_profile);
  }
  
  static ssize_t kone_sysfs_set_startup_profile(struct device *dev,
  		struct device_attribute *attr, char const *buf, size_t size)
  {
  	struct kone_device *kone;
  	struct usb_device *usb_dev;
  	int retval;
  	unsigned long new_startup_profile;
  
  	dev = dev->parent->parent;
  	kone = hid_get_drvdata(dev_get_drvdata(dev));
  	usb_dev = interface_to_usbdev(to_usb_interface(dev));
  
  	retval = kstrtoul(buf, 10, &new_startup_profile);
  	if (retval)
  		return retval;
  
  	if (new_startup_profile  < 1 || new_startup_profile > 5)
  		return -EINVAL;
  
  	mutex_lock(&kone->kone_lock);
  
  	kone->settings.startup_profile = new_startup_profile;
  	kone_set_settings_checksum(&kone->settings);
  
  	retval = kone_set_settings(usb_dev, &kone->settings);
  	if (retval) {
  		mutex_unlock(&kone->kone_lock);
  		return retval;
  	}
  
  	/* changing the startup profile immediately activates this profile */
  	kone_profile_activated(kone, new_startup_profile);
  	kone_profile_report(kone, new_startup_profile);
  
  	mutex_unlock(&kone->kone_lock);
  	return size;
  }
  static DEVICE_ATTR(startup_profile, 0660, kone_sysfs_show_startup_profile,
  		   kone_sysfs_set_startup_profile);
  
  static struct attribute *kone_attrs[] = {
  	/*
  	 * Read actual dpi settings.
  	 * Returns raw value for further processing. Refer to enum
  	 * kone_polling_rates to get real value.
  	 */
  	&dev_attr_actual_dpi.attr,
  	&dev_attr_actual_profile.attr,
  
  	/*
  	 * The mouse can be equipped with one of four supplied weights from 5
  	 * to 20 grams which are recognized and its value can be read out.
  	 * This returns the raw value reported by the mouse for easy evaluation
  	 * by software. Refer to enum kone_weights to get corresponding real
  	 * weight.
  	 */
  	&dev_attr_weight.attr,
  
  	/*
  	 * Prints firmware version stored in mouse as integer.
  	 * The raw value reported by the mouse is returned for easy evaluation,
  	 * to get the real version number the decimal point has to be shifted 2
  	 * positions to the left. E.g. a value of 138 means 1.38.
  	 */
  	&dev_attr_firmware_version.attr,
  
  	/*
  	 * Prints state of Tracking Control Unit as number where 0 = off and
  	 * 1 = on. Writing 0 deactivates tcu and writing 1 calibrates and
  	 * activates the tcu
  	 */
  	&dev_attr_tcu.attr,
  
  	/* Prints and takes the number of the profile the mouse starts with */
  	&dev_attr_startup_profile.attr,
  	NULL,
  };
  
  static struct bin_attribute *kone_bin_attributes[] = {
  	&bin_attr_settings,
  	&bin_attr_profile1,
  	&bin_attr_profile2,
  	&bin_attr_profile3,
  	&bin_attr_profile4,
  	&bin_attr_profile5,
  	NULL,
  };
  
  static const struct attribute_group kone_group = {
  	.attrs = kone_attrs,
  	.bin_attrs = kone_bin_attributes,
  };
  
  static const struct attribute_group *kone_groups[] = {
  	&kone_group,
  	NULL,
  };
  
  static int kone_init_kone_device_struct(struct usb_device *usb_dev,
  		struct kone_device *kone)
  {
  	uint i;
  	int retval;
  
  	mutex_init(&kone->kone_lock);
  
  	for (i = 0; i < 5; ++i) {
  		retval = kone_get_profile(usb_dev, &kone->profiles[i], i + 1);
  		if (retval)
  			return retval;
  	}
  
  	retval = kone_get_settings(usb_dev, &kone->settings);
  	if (retval)
  		return retval;
  
  	retval = kone_get_firmware_version(usb_dev, &kone->firmware_version);
  	if (retval)
  		return retval;
  
  	kone_profile_activated(kone, kone->settings.startup_profile);
  
  	return 0;
  }
  
  /*
   * Since IGNORE_MOUSE quirk moved to hid-apple, there is no way to bind only to
   * mousepart if usb_hid is compiled into the kernel and kone is compiled as
   * module.
   * Secial behaviour is bound only to mousepart since only mouseevents contain
   * additional notifications.
   */
  static int kone_init_specials(struct hid_device *hdev)
  {
  	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
  	struct usb_device *usb_dev = interface_to_usbdev(intf);
  	struct kone_device *kone;
  	int retval;
  
  	if (intf->cur_altsetting->desc.bInterfaceProtocol
  			== USB_INTERFACE_PROTOCOL_MOUSE) {
  
  		kone = kzalloc(sizeof(*kone), GFP_KERNEL);
  		if (!kone) {
  			hid_err(hdev, "can't alloc device descriptor
  ");
  			return -ENOMEM;
  		}
  		hid_set_drvdata(hdev, kone);
  
  		retval = kone_init_kone_device_struct(usb_dev, kone);
  		if (retval) {
  			hid_err(hdev, "couldn't init struct kone_device
  ");
  			goto exit_free;
  		}
  
  		retval = roccat_connect(kone_class, hdev,
  				sizeof(struct kone_roccat_report));
  		if (retval < 0) {
  			hid_err(hdev, "couldn't init char dev
  ");
  			/* be tolerant about not getting chrdev */
  		} else {
  			kone->roccat_claimed = 1;
  			kone->chrdev_minor = retval;
  		}
  	} else {
  		hid_set_drvdata(hdev, NULL);
  	}
  
  	return 0;
  exit_free:
  	kfree(kone);
  	return retval;
  }
  
  static void kone_remove_specials(struct hid_device *hdev)
  {
  	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
  	struct kone_device *kone;
  
  	if (intf->cur_altsetting->desc.bInterfaceProtocol
  			== USB_INTERFACE_PROTOCOL_MOUSE) {
  		kone = hid_get_drvdata(hdev);
  		if (kone->roccat_claimed)
  			roccat_disconnect(kone->chrdev_minor);
  		kfree(hid_get_drvdata(hdev));
  	}
  }
  
  static int kone_probe(struct hid_device *hdev, const struct hid_device_id *id)
  {
  	int retval;
  
  	retval = hid_parse(hdev);
  	if (retval) {
  		hid_err(hdev, "parse failed
  ");
  		goto exit;
  	}
  
  	retval = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
  	if (retval) {
  		hid_err(hdev, "hw start failed
  ");
  		goto exit;
  	}
  
  	retval = kone_init_specials(hdev);
  	if (retval) {
  		hid_err(hdev, "couldn't install mouse
  ");
  		goto exit_stop;
  	}
  
  	return 0;
  
  exit_stop:
  	hid_hw_stop(hdev);
  exit:
  	return retval;
  }
  
  static void kone_remove(struct hid_device *hdev)
  {
  	kone_remove_specials(hdev);
  	hid_hw_stop(hdev);
  }
  
  /* handle special events and keep actual profile and dpi values up to date */
  static void kone_keep_values_up_to_date(struct kone_device *kone,
  		struct kone_mouse_event const *event)
  {
  	switch (event->event) {
  	case kone_mouse_event_switch_profile:
  		kone->actual_dpi = kone->profiles[event->value - 1].
  				startup_dpi;
  	case kone_mouse_event_osd_profile:
  		kone->actual_profile = event->value;
  		break;
  	case kone_mouse_event_switch_dpi:
  	case kone_mouse_event_osd_dpi:
  		kone->actual_dpi = event->value;
  		break;
  	}
  }
  
  static void kone_report_to_chrdev(struct kone_device const *kone,
  		struct kone_mouse_event const *event)
  {
  	struct kone_roccat_report roccat_report;
  
  	switch (event->event) {
  	case kone_mouse_event_switch_profile:
  	case kone_mouse_event_switch_dpi:
  	case kone_mouse_event_osd_profile:
  	case kone_mouse_event_osd_dpi:
  		roccat_report.event = event->event;
  		roccat_report.value = event->value;
  		roccat_report.key = 0;
  		roccat_report_event(kone->chrdev_minor,
  				(uint8_t *)&roccat_report);
  		break;
  	case kone_mouse_event_call_overlong_macro:
  	case kone_mouse_event_multimedia:
  		if (event->value == kone_keystroke_action_press) {
  			roccat_report.event = event->event;
  			roccat_report.value = kone->actual_profile;
  			roccat_report.key = event->macro_key;
  			roccat_report_event(kone->chrdev_minor,
  					(uint8_t *)&roccat_report);
  		}
  		break;
  	}
  
  }
  
  /*
   * Is called for keyboard- and mousepart.
   * Only mousepart gets informations about special events in its extended event
   * structure.
   */
  static int kone_raw_event(struct hid_device *hdev, struct hid_report *report,
  		u8 *data, int size)
  {
  	struct kone_device *kone = hid_get_drvdata(hdev);
  	struct kone_mouse_event *event = (struct kone_mouse_event *)data;
  
  	/* keyboard events are always processed by default handler */
  	if (size != sizeof(struct kone_mouse_event))
  		return 0;
  
  	if (kone == NULL)
  		return 0;
  
  	/*
  	 * Firmware 1.38 introduced new behaviour for tilt and special buttons.
  	 * Pressed button is reported in each movement event.
  	 * Workaround sends only one event per press.
  	 */
  	if (memcmp(&kone->last_mouse_event.tilt, &event->tilt, 5))
  		memcpy(&kone->last_mouse_event, event,
  				sizeof(struct kone_mouse_event));
  	else
  		memset(&event->tilt, 0, 5);
  
  	kone_keep_values_up_to_date(kone, event);
  
  	if (kone->roccat_claimed)
  		kone_report_to_chrdev(kone, event);
  
  	return 0; /* always do further processing */
  }
  
  static const struct hid_device_id kone_devices[] = {
  	{ HID_USB_DEVICE(USB_VENDOR_ID_ROCCAT, USB_DEVICE_ID_ROCCAT_KONE) },
  	{ }
  };
  
  MODULE_DEVICE_TABLE(hid, kone_devices);
  
  static struct hid_driver kone_driver = {
  		.name = "kone",
  		.id_table = kone_devices,
  		.probe = kone_probe,
  		.remove = kone_remove,
  		.raw_event = kone_raw_event
  };
  
  static int __init kone_init(void)
  {
  	int retval;
  
  	/* class name has to be same as driver name */
  	kone_class = class_create(THIS_MODULE, "kone");
  	if (IS_ERR(kone_class))
  		return PTR_ERR(kone_class);
  	kone_class->dev_groups = kone_groups;
  
  	retval = hid_register_driver(&kone_driver);
  	if (retval)
  		class_destroy(kone_class);
  	return retval;
  }
  
  static void __exit kone_exit(void)
  {
  	hid_unregister_driver(&kone_driver);
  	class_destroy(kone_class);
  }
  
  module_init(kone_init);
  module_exit(kone_exit);
  
  MODULE_AUTHOR("Stefan Achatz");
  MODULE_DESCRIPTION("USB Roccat Kone driver");
  MODULE_LICENSE("GPL v2");