1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Force feedback support for Logitech RumblePad and Rumblepad 2
4 *
5 * Copyright (c) 2008 Anssi Hannula <anssi.hannula@gmail.com>
6 */
7
8 /*
9 */
10
11
12 #include <linux/input.h>
13 #include <linux/slab.h>
14 #include <linux/hid.h>
15
16 #include "hid-lg.h"
17
18 struct lg2ff_device {
19 struct hid_report *report;
20 };
21
play_effect(struct input_dev * dev,void * data,struct ff_effect * effect)22 static int play_effect(struct input_dev *dev, void *data,
23 struct ff_effect *effect)
24 {
25 struct hid_device *hid = input_get_drvdata(dev);
26 struct lg2ff_device *lg2ff = data;
27 int weak, strong;
28
29 strong = effect->u.rumble.strong_magnitude;
30 weak = effect->u.rumble.weak_magnitude;
31
32 if (weak || strong) {
33 weak = weak * 0xff / 0xffff;
34 strong = strong * 0xff / 0xffff;
35
36 lg2ff->report->field[0]->value[0] = 0x51;
37 lg2ff->report->field[0]->value[2] = weak;
38 lg2ff->report->field[0]->value[4] = strong;
39 } else {
40 lg2ff->report->field[0]->value[0] = 0xf3;
41 lg2ff->report->field[0]->value[2] = 0x00;
42 lg2ff->report->field[0]->value[4] = 0x00;
43 }
44
45 hid_hw_request(hid, lg2ff->report, HID_REQ_SET_REPORT);
46 return 0;
47 }
48
lg2ff_init(struct hid_device * hid)49 int lg2ff_init(struct hid_device *hid)
50 {
51 struct lg2ff_device *lg2ff;
52 struct hid_report *report;
53 struct hid_input *hidinput;
54 struct input_dev *dev;
55 int error;
56
57 if (list_empty(&hid->inputs)) {
58 hid_err(hid, "no inputs found\n");
59 return -ENODEV;
60 }
61 hidinput = list_entry(hid->inputs.next, struct hid_input, list);
62 dev = hidinput->input;
63
64 /* Check that the report looks ok */
65 report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7);
66 if (!report)
67 return -ENODEV;
68
69 lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
70 if (!lg2ff)
71 return -ENOMEM;
72
73 set_bit(FF_RUMBLE, dev->ffbit);
74
75 error = input_ff_create_memless(dev, lg2ff, play_effect);
76 if (error) {
77 kfree(lg2ff);
78 return error;
79 }
80
81 lg2ff->report = report;
82 report->field[0]->value[0] = 0xf3;
83 report->field[0]->value[1] = 0x00;
84 report->field[0]->value[2] = 0x00;
85 report->field[0]->value[3] = 0x00;
86 report->field[0]->value[4] = 0x00;
87 report->field[0]->value[5] = 0x00;
88 report->field[0]->value[6] = 0x00;
89
90 hid_hw_request(hid, report, HID_REQ_SET_REPORT);
91
92 hid_info(hid, "Force feedback for Logitech variant 2 rumble devices by Anssi Hannula <anssi.hannula@gmail.com>\n");
93
94 return 0;
95 }
96