1/*
2 * HID driver for Redragon keyboards
3 *
4 * Copyright (c) 2017 Robert Munteanu
5 * SPDX-License-Identifier: GPL-2.0+
6 */
7
8/*
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 */
14
15#include <linux/device.h>
16#include <linux/hid.h>
17#include <linux/module.h>
18
19#include "hid-ids.h"
20
21
22/*
23 * The Redragon Asura keyboard sends an incorrect HID descriptor.
24 * At byte 100 it contains
25 *
26 * 0x81, 0x00
27 *
28 * which is Input (Data, Arr, Abs), but it should be
29 *
30 * 0x81, 0x02
31 *
32 * which is Input (Data, Var, Abs), which is consistent with the way
33 * key codes are generated.
34 */
35
36static __u8 *redragon_report_fixup(struct hid_device *hdev, __u8 *rdesc,
37 unsigned int *rsize)
38{
39 if (*rsize >= 102 && rdesc[100] == 0x81 && rdesc[101] == 0x00) {
40 dev_info(&hdev->dev, "Fixing Redragon ASURA report descriptor.\n");
41 rdesc[101] = 0x02;
42 }
43
44 return rdesc;
45}
46
47static const struct hid_device_id redragon_devices[] = {
48 {HID_USB_DEVICE(USB_VENDOR_ID_JESS, USB_DEVICE_ID_REDRAGON_ASURA)},
49 {}
50};
51
52MODULE_DEVICE_TABLE(hid, redragon_devices);
53
54static struct hid_driver redragon_driver = {
55 .name = "redragon",
56 .id_table = redragon_devices,
57 .report_fixup = redragon_report_fixup
58};
59
60module_hid_driver(redragon_driver);
61
62MODULE_LICENSE("GPL");
63