1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * HID driver for some a4tech "special" devices
4 *
5 * Copyright (c) 1999 Andreas Gal
6 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
7 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
8 * Copyright (c) 2006-2007 Jiri Kosina
9 * Copyright (c) 2008 Jiri Slaby
10 */
11
12/*
13 */
14
15#include <linux/device.h>
16#include <linux/input.h>
17#include <linux/hid.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20
21#include "hid-ids.h"
22
23#define A4_2WHEEL_MOUSE_HACK_7 0x01
24#define A4_2WHEEL_MOUSE_HACK_B8 0x02
25
26#define A4_WHEEL_ORIENTATION (HID_UP_GENDESK | 0x000000b8)
27
28struct a4tech_sc {
29 unsigned long quirks;
30 unsigned int hw_wheel;
31 __s32 delayed_value;
32};
33
34static int a4_input_mapping(struct hid_device *hdev, struct hid_input *hi,
35 struct hid_field *field, struct hid_usage *usage,
36 unsigned long **bit, int *max)
37{
38 struct a4tech_sc *a4 = hid_get_drvdata(hdev);
39
40 if (a4->quirks & A4_2WHEEL_MOUSE_HACK_B8 &&
41 usage->hid == A4_WHEEL_ORIENTATION) {
42 /*
43 * We do not want to have this usage mapped to anything as it's
44 * nonstandard and doesn't really behave like an HID report.
45 * It's only selecting the orientation (vertical/horizontal) of
46 * the previous mouse wheel report. The input_events will be
47 * generated once both reports are recorded in a4_event().
48 */
49 return -1;
50 }
51
52 return 0;
53
54}
55
56static int a4_input_mapped(struct hid_device *hdev, struct hid_input *hi,
57 struct hid_field *field, struct hid_usage *usage,
58 unsigned long **bit, int *max)
59{
60 struct a4tech_sc *a4 = hid_get_drvdata(hdev);
61
62 if (usage->type == EV_REL && usage->code == REL_WHEEL_HI_RES) {
63 set_bit(REL_HWHEEL, addr: *bit);
64 set_bit(REL_HWHEEL_HI_RES, addr: *bit);
65 }
66
67 if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007)
68 return -1;
69
70 return 0;
71}
72
73static int a4_event(struct hid_device *hdev, struct hid_field *field,
74 struct hid_usage *usage, __s32 value)
75{
76 struct a4tech_sc *a4 = hid_get_drvdata(hdev);
77 struct input_dev *input;
78
79 if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput)
80 return 0;
81
82 input = field->hidinput->input;
83
84 if (a4->quirks & A4_2WHEEL_MOUSE_HACK_B8) {
85 if (usage->type == EV_REL && usage->code == REL_WHEEL_HI_RES) {
86 a4->delayed_value = value;
87 return 1;
88 }
89
90 if (usage->hid == A4_WHEEL_ORIENTATION) {
91 input_event(dev: input, EV_REL, code: value ? REL_HWHEEL :
92 REL_WHEEL, value: a4->delayed_value);
93 input_event(dev: input, EV_REL, code: value ? REL_HWHEEL_HI_RES :
94 REL_WHEEL_HI_RES, value: a4->delayed_value * 120);
95 return 1;
96 }
97 }
98
99 if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007) {
100 a4->hw_wheel = !!value;
101 return 1;
102 }
103
104 if (usage->code == REL_WHEEL_HI_RES && a4->hw_wheel) {
105 input_event(dev: input, type: usage->type, REL_HWHEEL, value);
106 input_event(dev: input, type: usage->type, REL_HWHEEL_HI_RES, value: value * 120);
107 return 1;
108 }
109
110 return 0;
111}
112
113static int a4_probe(struct hid_device *hdev, const struct hid_device_id *id)
114{
115 struct a4tech_sc *a4;
116 int ret;
117
118 a4 = devm_kzalloc(dev: &hdev->dev, size: sizeof(*a4), GFP_KERNEL);
119 if (a4 == NULL) {
120 hid_err(hdev, "can't alloc device descriptor\n");
121 return -ENOMEM;
122 }
123
124 a4->quirks = id->driver_data;
125
126 hid_set_drvdata(hdev, data: a4);
127
128 ret = hid_parse(hdev);
129 if (ret) {
130 hid_err(hdev, "parse failed\n");
131 return ret;
132 }
133
134 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
135 if (ret) {
136 hid_err(hdev, "hw start failed\n");
137 return ret;
138 }
139
140 return 0;
141}
142
143static const struct hid_device_id a4_devices[] = {
144 { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_WCP32PU),
145 .driver_data = A4_2WHEEL_MOUSE_HACK_7 },
146 { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_X5_005D),
147 .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
148 { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_RP_649),
149 .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
150 { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_NB_95),
151 .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
152 { }
153};
154MODULE_DEVICE_TABLE(hid, a4_devices);
155
156static struct hid_driver a4_driver = {
157 .name = "a4tech",
158 .id_table = a4_devices,
159 .input_mapping = a4_input_mapping,
160 .input_mapped = a4_input_mapped,
161 .event = a4_event,
162 .probe = a4_probe,
163};
164module_hid_driver(a4_driver);
165
166MODULE_LICENSE("GPL");
167

source code of linux/drivers/hid/hid-a4tech.c