// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   *  HID driver for Speedlink Vicious and Divine Cezanne (USB mouse).
   *  Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
   *  the HID descriptor.
   *

   *  Copyright (c) 2011, 2013 Stefan Kriwanek <dev@stefankriwanek.de>

   */
  
  /*

   */
  
  #include <linux/device.h>
  #include <linux/hid.h>
  #include <linux/module.h>

  
  #include "hid-ids.h"

  
  static const struct hid_device_id speedlink_devices[] = {
  	{ HID_USB_DEVICE(USB_VENDOR_ID_X_TENSIONS, USB_DEVICE_ID_SPEEDLINK_VAD_CEZANNE)},
  	{ }
  };
  
  static int speedlink_input_mapping(struct hid_device *hdev,
  		struct hid_input *hi,
  		struct hid_field *field, struct hid_usage *usage,
  		unsigned long **bit, int *max)
  {
  	/*
  	 * The Cezanne mouse has a second "keyboard" USB endpoint for it is
  	 * able to map keyboard events to the button presses.
  	 * It sends a standard keyboard report descriptor, though, whose
  	 * LEDs we ignore.
  	 */
  	switch (usage->hid & HID_USAGE_PAGE) {
  	case HID_UP_LED:
  		return -1;
  	}
  	return 0;
  }
  
  static int speedlink_event(struct hid_device *hdev, struct hid_field *field,
  		struct hid_usage *usage, __s32 value)
  {
  	/* No other conditions due to usage_table. */

  
  	/* This fixes the "jumpy" cursor occuring due to invalid events sent
  	 * by the device. Some devices only send them with value==+256, others
  	 * don't. However, catching abs(value)>=256 is restrictive enough not
  	 * to interfere with devices that were bug-free (has been tested).
  	 */
  	if (abs(value) >= 256)

  		return 1;
  	/* Drop useless distance 0 events (on button clicks etc.) as well */
  	if (value == 0)
  		return 1;
  
  	return 0;
  }
  
  MODULE_DEVICE_TABLE(hid, speedlink_devices);
  
  static const struct hid_usage_id speedlink_grabbed_usages[] = {
  	{ HID_GD_X, EV_REL, 0 },
  	{ HID_GD_Y, EV_REL, 1 },
  	{ HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
  };
  
  static struct hid_driver speedlink_driver = {
  	.name = "speedlink",
  	.id_table = speedlink_devices,
  	.usage_table = speedlink_grabbed_usages,
  	.input_mapping = speedlink_input_mapping,
  	.event = speedlink_event,
  };

  module_hid_driver(speedlink_driver);

  MODULE_LICENSE("GPL");