1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * HID driver for Redragon keyboards
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Copyright (c) 2017 Robert Munteanu
5*4882a593Smuzhiyun * SPDX-License-Identifier: GPL-2.0+
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun /*
9*4882a593Smuzhiyun * This program is free software; you can redistribute it and/or modify it
10*4882a593Smuzhiyun * under the terms of the GNU General Public License as published by the Free
11*4882a593Smuzhiyun * Software Foundation; either version 2 of the License, or (at your option)
12*4882a593Smuzhiyun * any later version.
13*4882a593Smuzhiyun */
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #include <linux/device.h>
16*4882a593Smuzhiyun #include <linux/hid.h>
17*4882a593Smuzhiyun #include <linux/module.h>
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include "hid-ids.h"
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun /*
23*4882a593Smuzhiyun * The Redragon Asura keyboard sends an incorrect HID descriptor.
24*4882a593Smuzhiyun * At byte 100 it contains
25*4882a593Smuzhiyun *
26*4882a593Smuzhiyun * 0x81, 0x00
27*4882a593Smuzhiyun *
28*4882a593Smuzhiyun * which is Input (Data, Arr, Abs), but it should be
29*4882a593Smuzhiyun *
30*4882a593Smuzhiyun * 0x81, 0x02
31*4882a593Smuzhiyun *
32*4882a593Smuzhiyun * which is Input (Data, Var, Abs), which is consistent with the way
33*4882a593Smuzhiyun * key codes are generated.
34*4882a593Smuzhiyun */
35*4882a593Smuzhiyun
redragon_report_fixup(struct hid_device * hdev,__u8 * rdesc,unsigned int * rsize)36*4882a593Smuzhiyun static __u8 *redragon_report_fixup(struct hid_device *hdev, __u8 *rdesc,
37*4882a593Smuzhiyun unsigned int *rsize)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun if (*rsize >= 102 && rdesc[100] == 0x81 && rdesc[101] == 0x00) {
40*4882a593Smuzhiyun dev_info(&hdev->dev, "Fixing Redragon ASURA report descriptor.\n");
41*4882a593Smuzhiyun rdesc[101] = 0x02;
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun return rdesc;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun static const struct hid_device_id redragon_devices[] = {
48*4882a593Smuzhiyun {HID_USB_DEVICE(USB_VENDOR_ID_JESS, USB_DEVICE_ID_REDRAGON_ASURA)},
49*4882a593Smuzhiyun {}
50*4882a593Smuzhiyun };
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun MODULE_DEVICE_TABLE(hid, redragon_devices);
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun static struct hid_driver redragon_driver = {
55*4882a593Smuzhiyun .name = "redragon",
56*4882a593Smuzhiyun .id_table = redragon_devices,
57*4882a593Smuzhiyun .report_fixup = redragon_report_fixup
58*4882a593Smuzhiyun };
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun module_hid_driver(redragon_driver);
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun MODULE_LICENSE("GPL");
63