1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  HID driver for Speedlink Vicious and Divine Cezanne (USB mouse).
4 *  Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
5 *  the HID descriptor.
6 *
7 *  Copyright (c) 2011, 2013 Stefan Kriwanek <dev@stefankriwanek.de>
8 */
9
10/*
11 */
12
13#include <linux/device.h>
14#include <linux/hid.h>
15#include <linux/module.h>
16
17#include "hid-ids.h"
18
19static const struct hid_device_id speedlink_devices[] = {
20	{ HID_USB_DEVICE(USB_VENDOR_ID_X_TENSIONS, USB_DEVICE_ID_SPEEDLINK_VAD_CEZANNE)},
21	{ }
22};
23
24static int speedlink_input_mapping(struct hid_device *hdev,
25		struct hid_input *hi,
26		struct hid_field *field, struct hid_usage *usage,
27		unsigned long **bit, int *max)
28{
29	/*
30	 * The Cezanne mouse has a second "keyboard" USB endpoint for it is
31	 * able to map keyboard events to the button presses.
32	 * It sends a standard keyboard report descriptor, though, whose
33	 * LEDs we ignore.
34	 */
35	switch (usage->hid & HID_USAGE_PAGE) {
36	case HID_UP_LED:
37		return -1;
38	}
39	return 0;
40}
41
42static int speedlink_event(struct hid_device *hdev, struct hid_field *field,
43		struct hid_usage *usage, __s32 value)
44{
45	/* No other conditions due to usage_table. */
46
47	/* This fixes the "jumpy" cursor occuring due to invalid events sent
48	 * by the device. Some devices only send them with value==+256, others
49	 * don't. However, catching abs(value)>=256 is restrictive enough not
50	 * to interfere with devices that were bug-free (has been tested).
51	 */
52	if (abs(value) >= 256)
53		return 1;
54	/* Drop useless distance 0 events (on button clicks etc.) as well */
55	if (value == 0)
56		return 1;
57
58	return 0;
59}
60
61MODULE_DEVICE_TABLE(hid, speedlink_devices);
62
63static const struct hid_usage_id speedlink_grabbed_usages[] = {
64	{ HID_GD_X, EV_REL, 0 },
65	{ HID_GD_Y, EV_REL, 1 },
66	{ HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
67};
68
69static struct hid_driver speedlink_driver = {
70	.name = "speedlink",
71	.id_table = speedlink_devices,
72	.usage_table = speedlink_grabbed_usages,
73	.input_mapping = speedlink_input_mapping,
74	.event = speedlink_event,
75};
76module_hid_driver(speedlink_driver);
77
78MODULE_LICENSE("GPL");
79