xref: /openbmc/linux/drivers/hid/hid-elecom.c (revision 68198dca)
1 /*
2  *  HID driver for ELECOM devices.
3  *  Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
4  *  Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com>
5  *  Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu>
6  *  Copyright (c) 2017 Alex Manoussakis <amanou@gnu.org>
7  */
8 
9 /*
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the Free
12  * Software Foundation; either version 2 of the License, or (at your option)
13  * any later version.
14  */
15 
16 #include <linux/device.h>
17 #include <linux/hid.h>
18 #include <linux/module.h>
19 
20 #include "hid-ids.h"
21 
22 static __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
23 		unsigned int *rsize)
24 {
25 	switch (hdev->product) {
26 	case USB_DEVICE_ID_ELECOM_BM084:
27 		/* The BM084 Bluetooth mouse includes a non-existing horizontal
28 		 * wheel in the HID descriptor. */
29 		if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
30 			hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
31 			rdesc[47] = 0x00;
32 		}
33 		break;
34 	case USB_DEVICE_ID_ELECOM_DEFT_WIRED:
35 	case USB_DEVICE_ID_ELECOM_DEFT_WIRELESS:
36 	case USB_DEVICE_ID_ELECOM_HUGE_WIRED:
37 	case USB_DEVICE_ID_ELECOM_HUGE_WIRELESS:
38 		/* The DEFT/HUGE trackball has eight buttons, but its descriptor
39 		 * only reports five, disabling the three Fn buttons on the top
40 		 * of the mouse.
41 		 *
42 		 * Apply the following diff to the descriptor:
43 		 *
44 		 * Collection (Physical),              Collection (Physical),
45 		 *     Report ID (1),                      Report ID (1),
46 		 *     Report Count (5),           ->      Report Count (8),
47 		 *     Report Size (1),                    Report Size (1),
48 		 *     Usage Page (Button),                Usage Page (Button),
49 		 *     Usage Minimum (01h),                Usage Minimum (01h),
50 		 *     Usage Maximum (05h),        ->      Usage Maximum (08h),
51 		 *     Logical Minimum (0),                Logical Minimum (0),
52 		 *     Logical Maximum (1),                Logical Maximum (1),
53 		 *     Input (Variable),                   Input (Variable),
54 		 *     Report Count (1),           ->      Report Count (0),
55 		 *     Report Size (3),                    Report Size (3),
56 		 *     Input (Constant),                   Input (Constant),
57 		 *     Report Size (16),                   Report Size (16),
58 		 *     Report Count (2),                   Report Count (2),
59 		 *     Usage Page (Desktop),               Usage Page (Desktop),
60 		 *     Usage (X),                          Usage (X),
61 		 *     Usage (Y),                          Usage (Y),
62 		 *     Logical Minimum (-32768),           Logical Minimum (-32768),
63 		 *     Logical Maximum (32767),            Logical Maximum (32767),
64 		 *     Input (Variable, Relative),         Input (Variable, Relative),
65 		 * End Collection,                     End Collection,
66 		 */
67 		if (*rsize == 213 && rdesc[13] == 5 && rdesc[21] == 5) {
68 			hid_info(hdev, "Fixing up Elecom DEFT/HUGE Fn buttons\n");
69 			rdesc[13] = 8; /* Button/Variable Report Count */
70 			rdesc[21] = 8; /* Button/Variable Usage Maximum */
71 			rdesc[29] = 0; /* Button/Constant Report Count */
72 		}
73 		break;
74 	}
75 	return rdesc;
76 }
77 
78 static const struct hid_device_id elecom_devices[] = {
79 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
80 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT_WIRED) },
81 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT_WIRELESS) },
82 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_HUGE_WIRED) },
83 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_HUGE_WIRELESS) },
84 	{ }
85 };
86 MODULE_DEVICE_TABLE(hid, elecom_devices);
87 
88 static struct hid_driver elecom_driver = {
89 	.name = "elecom",
90 	.id_table = elecom_devices,
91 	.report_fixup = elecom_report_fixup
92 };
93 module_hid_driver(elecom_driver);
94 
95 MODULE_LICENSE("GPL");
96