1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * HID driver for ELECOM devices:
4 * - BM084 Bluetooth Mouse
5 * - EX-G Trackballs (M-XT3DRBK, M-XT3URBK, M-XT4DRBK)
6 * - DEFT Trackballs (M-DT1DRBK, M-DT1URBK, M-DT2DRBK, M-DT2URBK)
7 * - HUGE Trackballs (M-HT1DRBK, M-HT1URBK)
8 * - HUGE Plus Trackball (M-HT1MRBK)
9 *
10 * Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
11 * Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com>
12 * Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu>
13 * Copyright (c) 2017 Alex Manoussakis <amanou@gnu.org>
14 * Copyright (c) 2017 Tomasz Kramkowski <tk@the-tk.com>
15 * Copyright (c) 2020 YOSHIOKA Takuma <lo48576@hard-wi.red>
16 * Copyright (c) 2022 Takahiro Fujii <fujii@xaxxi.net>
17 */
18
19 /*
20 */
21
22 #include <linux/device.h>
23 #include <linux/hid.h>
24 #include <linux/module.h>
25
26 #include "hid-ids.h"
27
28 /*
29 * Certain ELECOM mice misreport their button count meaning that they only work
30 * correctly with the ELECOM mouse assistant software which is unavailable for
31 * Linux. A four extra INPUT reports and a FEATURE report are described by the
32 * report descriptor but it does not appear that these enable software to
33 * control what the extra buttons map to. The only simple and straightforward
34 * solution seems to involve fixing up the report descriptor.
35 */
36 #define MOUSE_BUTTONS_MAX 8
mouse_button_fixup(struct hid_device * hdev,__u8 * rdesc,unsigned int rsize,unsigned int button_bit_count,unsigned int padding_bit,unsigned int button_report_size,unsigned int button_usage_maximum,int nbuttons)37 static void mouse_button_fixup(struct hid_device *hdev,
38 __u8 *rdesc, unsigned int rsize,
39 unsigned int button_bit_count,
40 unsigned int padding_bit,
41 unsigned int button_report_size,
42 unsigned int button_usage_maximum,
43 int nbuttons)
44 {
45 if (rsize < 32 || rdesc[button_bit_count] != 0x95 ||
46 rdesc[button_report_size] != 0x75 ||
47 rdesc[button_report_size + 1] != 0x01 ||
48 rdesc[button_usage_maximum] != 0x29 || rdesc[padding_bit] != 0x75)
49 return;
50 hid_info(hdev, "Fixing up Elecom mouse button count\n");
51 nbuttons = clamp(nbuttons, 0, MOUSE_BUTTONS_MAX);
52 rdesc[button_bit_count + 1] = nbuttons;
53 rdesc[button_usage_maximum + 1] = nbuttons;
54 rdesc[padding_bit + 1] = MOUSE_BUTTONS_MAX - nbuttons;
55 }
56
elecom_report_fixup(struct hid_device * hdev,__u8 * rdesc,unsigned int * rsize)57 static const __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
58 unsigned int *rsize)
59 {
60 switch (hdev->product) {
61 case USB_DEVICE_ID_ELECOM_BM084:
62 /* The BM084 Bluetooth mouse includes a non-existing horizontal
63 * wheel in the HID descriptor. */
64 if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
65 hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
66 rdesc[47] = 0x00;
67 }
68 break;
69 case USB_DEVICE_ID_ELECOM_M_XGL20DLBK:
70 /*
71 * Report descriptor format:
72 * 20: button bit count
73 * 28: padding bit count
74 * 22: button report size
75 * 14: button usage maximum
76 */
77 mouse_button_fixup(hdev, rdesc, *rsize, 20, 28, 22, 14, 8);
78 break;
79 case USB_DEVICE_ID_ELECOM_M_XT3URBK_00FB:
80 case USB_DEVICE_ID_ELECOM_M_XT3URBK_018F:
81 case USB_DEVICE_ID_ELECOM_M_XT3DRBK_00FC:
82 case USB_DEVICE_ID_ELECOM_M_XT4DRBK:
83 /*
84 * Report descriptor format:
85 * 12: button bit count
86 * 30: padding bit count
87 * 14: button report size
88 * 20: button usage maximum
89 */
90 mouse_button_fixup(hdev, rdesc, *rsize, 12, 30, 14, 20, 6);
91 break;
92 case USB_DEVICE_ID_ELECOM_M_DT1URBK:
93 case USB_DEVICE_ID_ELECOM_M_DT1DRBK:
94 case USB_DEVICE_ID_ELECOM_M_HT1URBK_010C:
95 case USB_DEVICE_ID_ELECOM_M_HT1URBK_019B:
96 case USB_DEVICE_ID_ELECOM_M_HT1DRBK_010D:
97 /*
98 * Report descriptor format:
99 * 12: button bit count
100 * 30: padding bit count
101 * 14: button report size
102 * 20: button usage maximum
103 */
104 mouse_button_fixup(hdev, rdesc, *rsize, 12, 30, 14, 20, 8);
105 break;
106 case USB_DEVICE_ID_ELECOM_M_XT3DRBK_018C:
107 /*
108 * Report descriptor format:
109 * 22: button bit count
110 * 30: padding bit count
111 * 24: button report size
112 * 16: button usage maximum
113 */
114 mouse_button_fixup(hdev, rdesc, *rsize, 22, 30, 24, 16, 6);
115 break;
116 case USB_DEVICE_ID_ELECOM_M_DT2DRBK:
117 case USB_DEVICE_ID_ELECOM_M_HT1DRBK_011C:
118 /*
119 * Report descriptor format:
120 * 22: button bit count
121 * 30: padding bit count
122 * 24: button report size
123 * 16: button usage maximum
124 */
125 mouse_button_fixup(hdev, rdesc, *rsize, 22, 30, 24, 16, 8);
126 break;
127 case USB_DEVICE_ID_ELECOM_M_HT1MRBK:
128 case USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB:
129 case USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC:
130 /*
131 * Report descriptor format:
132 * 24: button bit count
133 * 28: padding bit count
134 * 22: button report size
135 * 16: button usage maximum
136 */
137 mouse_button_fixup(hdev, rdesc, *rsize, 24, 28, 22, 16, 8);
138 break;
139 }
140 return rdesc;
141 }
142
143 static const struct hid_device_id elecom_devices[] = {
144 { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
145 { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AC) },
146 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XGL20DLBK) },
147 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_00FB) },
148 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK_018F) },
149 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3DRBK_00FC) },
150 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3DRBK_018C) },
151 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT4DRBK) },
152 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1URBK) },
153 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1DRBK) },
154 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT2DRBK) },
155 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK_010C) },
156 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK_019B) },
157 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_010D) },
158 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK_011C) },
159 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK) },
160 { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1MRBK_01AB) },
161 { }
162 };
163 MODULE_DEVICE_TABLE(hid, elecom_devices);
164
165 static struct hid_driver elecom_driver = {
166 .name = "elecom",
167 .id_table = elecom_devices,
168 .report_fixup = elecom_report_fixup
169 };
170 module_hid_driver(elecom_driver);
171
172 MODULE_DESCRIPTION("HID driver for ELECOM devices");
173 MODULE_LICENSE("GPL");
174