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
18struct lg2ff_device {
19	struct hid_report *report;
20};
21
22static 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
49int 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