xref: /linux/drivers/hid/hid-rakk.c (revision 0eaed89c18aeedf0898baf2dbf5ff027c6795152)
1*15a0449cSKarl Cayme // SPDX-License-Identifier: GPL-2.0
2*15a0449cSKarl Cayme /*
3*15a0449cSKarl Cayme  *  HID driver for Rakk devices
4*15a0449cSKarl Cayme  *
5*15a0449cSKarl Cayme  *  Copyright (c) 2026 Karl Cayme
6*15a0449cSKarl Cayme  *
7*15a0449cSKarl Cayme  *  The Rakk Dasig X gaming mouse has a faulty HID report descriptor that
8*15a0449cSKarl Cayme  *  declares USAGE_MAXIMUM = 3 (buttons 1-3) while actually sending 5 button
9*15a0449cSKarl Cayme  *  bits (REPORT_COUNT = 5). This causes the kernel to ignore side buttons
10*15a0449cSKarl Cayme  *  (buttons 4 and 5). This driver fixes the descriptor so all 5 buttons
11*15a0449cSKarl Cayme  *  are properly recognized across 3 modes (wired, dongle, and Bluetooth).
12*15a0449cSKarl Cayme  */
13*15a0449cSKarl Cayme 
14*15a0449cSKarl Cayme #include <linux/device.h>
15*15a0449cSKarl Cayme #include <linux/hid.h>
16*15a0449cSKarl Cayme #include <linux/module.h>
17*15a0449cSKarl Cayme #include "hid-ids.h"
18*15a0449cSKarl Cayme 
19*15a0449cSKarl Cayme /*
20*15a0449cSKarl Cayme  * The faulty byte is at offset 17 in the report descriptor for all three
21*15a0449cSKarl Cayme  * connection modes (USB direct, wireless dongle, and Bluetooth).
22*15a0449cSKarl Cayme  *
23*15a0449cSKarl Cayme  * Bytes 16-17 are: 0x29 0x03 (USAGE_MAXIMUM = 3)
24*15a0449cSKarl Cayme  * The fix changes byte 17 to 0x05 (USAGE_MAXIMUM = 5).
25*15a0449cSKarl Cayme  *
26*15a0449cSKarl Cayme  * Original descriptor bytes 0-17:
27*15a0449cSKarl Cayme  *   05 01 09 02 a1 01 85 01 09 01 a1 00 05 09 19 01 29 03
28*15a0449cSKarl Cayme  *                                                       ^^
29*15a0449cSKarl Cayme  *   Should be 0x05 to declare 5 buttons instead of 3.
30*15a0449cSKarl Cayme  */
31*15a0449cSKarl Cayme #define RAKK_RDESC_USAGE_MAX_OFFSET	17
32*15a0449cSKarl Cayme #define RAKK_RDESC_USAGE_MAX_ORIG	0x03
33*15a0449cSKarl Cayme #define RAKK_RDESC_USAGE_MAX_FIXED	0x05
34*15a0449cSKarl Cayme #define RAKK_RDESC_USB_SIZE		193
35*15a0449cSKarl Cayme #define RAKK_RDESC_DONGLE_SIZE		150
36*15a0449cSKarl Cayme #define RAKK_RDESC_BT_SIZE		89
37*15a0449cSKarl Cayme 
38*15a0449cSKarl Cayme static const __u8 *rakk_report_fixup(struct hid_device *hdev, __u8 *rdesc,
39*15a0449cSKarl Cayme 				     unsigned int *rsize)
40*15a0449cSKarl Cayme {
41*15a0449cSKarl Cayme 	if (((*rsize == RAKK_RDESC_USB_SIZE &&
42*15a0449cSKarl Cayme 	      hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X) ||
43*15a0449cSKarl Cayme 	     (*rsize == RAKK_RDESC_DONGLE_SIZE &&
44*15a0449cSKarl Cayme 	      hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X_DONGLE) ||
45*15a0449cSKarl Cayme 	     (*rsize == RAKK_RDESC_BT_SIZE &&
46*15a0449cSKarl Cayme 	      hdev->product == USB_DEVICE_ID_TELINK_RAKK_DASIG_X_BT)) &&
47*15a0449cSKarl Cayme 	    rdesc[RAKK_RDESC_USAGE_MAX_OFFSET] == RAKK_RDESC_USAGE_MAX_ORIG) {
48*15a0449cSKarl Cayme 		hid_info(hdev, "fixing Rakk Dasig X button count (3 -> 5)\n");
49*15a0449cSKarl Cayme 		rdesc[RAKK_RDESC_USAGE_MAX_OFFSET] = RAKK_RDESC_USAGE_MAX_FIXED;
50*15a0449cSKarl Cayme 	}
51*15a0449cSKarl Cayme 
52*15a0449cSKarl Cayme 	return rdesc;
53*15a0449cSKarl Cayme }
54*15a0449cSKarl Cayme 
55*15a0449cSKarl Cayme static const struct hid_device_id rakk_devices[] = {
56*15a0449cSKarl Cayme 	{ HID_USB_DEVICE(USB_VENDOR_ID_TELINK,
57*15a0449cSKarl Cayme 			 USB_DEVICE_ID_TELINK_RAKK_DASIG_X) },
58*15a0449cSKarl Cayme 	{ HID_USB_DEVICE(USB_VENDOR_ID_TELINK,
59*15a0449cSKarl Cayme 			 USB_DEVICE_ID_TELINK_RAKK_DASIG_X_DONGLE) },
60*15a0449cSKarl Cayme 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_TELINK,
61*15a0449cSKarl Cayme 			       USB_DEVICE_ID_TELINK_RAKK_DASIG_X_BT) },
62*15a0449cSKarl Cayme 	{ }
63*15a0449cSKarl Cayme };
64*15a0449cSKarl Cayme MODULE_DEVICE_TABLE(hid, rakk_devices);
65*15a0449cSKarl Cayme 
66*15a0449cSKarl Cayme static struct hid_driver rakk_driver = {
67*15a0449cSKarl Cayme 	.name = "rakk",
68*15a0449cSKarl Cayme 	.id_table = rakk_devices,
69*15a0449cSKarl Cayme 	.report_fixup = rakk_report_fixup,
70*15a0449cSKarl Cayme };
71*15a0449cSKarl Cayme module_hid_driver(rakk_driver);
72*15a0449cSKarl Cayme 
73*15a0449cSKarl Cayme MODULE_DESCRIPTION("HID driver for Rakk Dasig X mouse - fix side button support");
74*15a0449cSKarl Cayme MODULE_LICENSE("GPL");
75*15a0449cSKarl Cayme MODULE_AUTHOR("Karl Cayme");
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