1 /*
2  *  Force feedback support for Logitech RumblePad and Rumblepad 2
3  *
4  *  Copyright (c) 2008 Anssi Hannula <anssi.hannula@gmail.com>
5  */
6 
7 /*
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  */
22 
23 
24 #include <linux/input.h>
25 #include <linux/slab.h>
26 #include <linux/hid.h>
27 
28 #include "hid-lg.h"
29 
30 struct lg2ff_device {
31 	struct hid_report *report;
32 };
33 
play_effect(struct input_dev * dev,void * data,struct ff_effect * effect)34 static int play_effect(struct input_dev *dev, void *data,
35 			 struct ff_effect *effect)
36 {
37 	struct hid_device *hid = input_get_drvdata(dev);
38 	struct lg2ff_device *lg2ff = data;
39 	int weak, strong;
40 
41 	strong = effect->u.rumble.strong_magnitude;
42 	weak = effect->u.rumble.weak_magnitude;
43 
44 	if (weak || strong) {
45 		weak = weak * 0xff / 0xffff;
46 		strong = strong * 0xff / 0xffff;
47 
48 		lg2ff->report->field[0]->value[0] = 0x51;
49 		lg2ff->report->field[0]->value[2] = weak;
50 		lg2ff->report->field[0]->value[4] = strong;
51 	} else {
52 		lg2ff->report->field[0]->value[0] = 0xf3;
53 		lg2ff->report->field[0]->value[2] = 0x00;
54 		lg2ff->report->field[0]->value[4] = 0x00;
55 	}
56 
57 	hid_hw_request(hid, lg2ff->report, HID_REQ_SET_REPORT);
58 	return 0;
59 }
60 
lg2ff_init(struct hid_device * hid)61 int lg2ff_init(struct hid_device *hid)
62 {
63 	struct lg2ff_device *lg2ff;
64 	struct hid_report *report;
65 	struct hid_input *hidinput;
66 	struct input_dev *dev;
67 	int error;
68 
69 	if (list_empty(&hid->inputs)) {
70 		hid_err(hid, "no inputs found\n");
71 		return -ENODEV;
72 	}
73 	hidinput = list_entry(hid->inputs.next, struct hid_input, list);
74 	dev = hidinput->input;
75 
76 	/* Check that the report looks ok */
77 	report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7);
78 	if (!report)
79 		return -ENODEV;
80 
81 	lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
82 	if (!lg2ff)
83 		return -ENOMEM;
84 
85 	set_bit(FF_RUMBLE, dev->ffbit);
86 
87 	error = input_ff_create_memless(dev, lg2ff, play_effect);
88 	if (error) {
89 		kfree(lg2ff);
90 		return error;
91 	}
92 
93 	lg2ff->report = report;
94 	report->field[0]->value[0] = 0xf3;
95 	report->field[0]->value[1] = 0x00;
96 	report->field[0]->value[2] = 0x00;
97 	report->field[0]->value[3] = 0x00;
98 	report->field[0]->value[4] = 0x00;
99 	report->field[0]->value[5] = 0x00;
100 	report->field[0]->value[6] = 0x00;
101 
102 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
103 
104 	hid_info(hid, "Force feedback for Logitech variant 2 rumble devices by Anssi Hannula <anssi.hannula@gmail.com>\n");
105 
106 	return 0;
107 }
108