xref: /openbmc/linux/drivers/hid/hid-lg2ff.c (revision 39b6f3aa)
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 
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 
61 int lg2ff_init(struct hid_device *hid)
62 {
63 	struct lg2ff_device *lg2ff;
64 	struct hid_report *report;
65 	struct hid_input *hidinput = list_entry(hid->inputs.next,
66 						struct hid_input, list);
67 	struct list_head *report_list =
68 			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
69 	struct input_dev *dev = hidinput->input;
70 	int error;
71 
72 	if (list_empty(report_list)) {
73 		hid_err(hid, "no output report found\n");
74 		return -ENODEV;
75 	}
76 
77 	report = list_entry(report_list->next, struct hid_report, list);
78 
79 	if (report->maxfield < 1) {
80 		hid_err(hid, "output report is empty\n");
81 		return -ENODEV;
82 	}
83 	if (report->field[0]->report_count < 7) {
84 		hid_err(hid, "not enough values in the field\n");
85 		return -ENODEV;
86 	}
87 
88 	lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
89 	if (!lg2ff)
90 		return -ENOMEM;
91 
92 	set_bit(FF_RUMBLE, dev->ffbit);
93 
94 	error = input_ff_create_memless(dev, lg2ff, play_effect);
95 	if (error) {
96 		kfree(lg2ff);
97 		return error;
98 	}
99 
100 	lg2ff->report = report;
101 	report->field[0]->value[0] = 0xf3;
102 	report->field[0]->value[1] = 0x00;
103 	report->field[0]->value[2] = 0x00;
104 	report->field[0]->value[3] = 0x00;
105 	report->field[0]->value[4] = 0x00;
106 	report->field[0]->value[5] = 0x00;
107 	report->field[0]->value[6] = 0x00;
108 
109 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
110 
111 	hid_info(hid, "Force feedback for Logitech RumblePad/Rumblepad 2 by Anssi Hannula <anssi.hannula@gmail.com>\n");
112 
113 	return 0;
114 }
115