xref: /linux/drivers/hid/hid-lg2ff.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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/usb.h>
27 #include <linux/hid.h>
28 
29 #include "usbhid/usbhid.h"
30 #include "hid-lg.h"
31 
32 struct lg2ff_device {
33 	struct hid_report *report;
34 };
35 
36 static int play_effect(struct input_dev *dev, void *data,
37 			 struct ff_effect *effect)
38 {
39 	struct hid_device *hid = input_get_drvdata(dev);
40 	struct lg2ff_device *lg2ff = data;
41 	int weak, strong;
42 
43 	strong = effect->u.rumble.strong_magnitude;
44 	weak = effect->u.rumble.weak_magnitude;
45 
46 	if (weak || strong) {
47 		weak = weak * 0xff / 0xffff;
48 		strong = strong * 0xff / 0xffff;
49 
50 		lg2ff->report->field[0]->value[0] = 0x51;
51 		lg2ff->report->field[0]->value[2] = weak;
52 		lg2ff->report->field[0]->value[4] = strong;
53 	} else {
54 		lg2ff->report->field[0]->value[0] = 0xf3;
55 		lg2ff->report->field[0]->value[2] = 0x00;
56 		lg2ff->report->field[0]->value[4] = 0x00;
57 	}
58 
59 	usbhid_submit_report(hid, lg2ff->report, USB_DIR_OUT);
60 	return 0;
61 }
62 
63 int lg2ff_init(struct hid_device *hid)
64 {
65 	struct lg2ff_device *lg2ff;
66 	struct hid_report *report;
67 	struct hid_input *hidinput = list_entry(hid->inputs.next,
68 						struct hid_input, list);
69 	struct list_head *report_list =
70 			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
71 	struct input_dev *dev = hidinput->input;
72 	int error;
73 
74 	if (list_empty(report_list)) {
75 		hid_err(hid, "no output report found\n");
76 		return -ENODEV;
77 	}
78 
79 	report = list_entry(report_list->next, struct hid_report, list);
80 
81 	if (report->maxfield < 1) {
82 		hid_err(hid, "output report is empty\n");
83 		return -ENODEV;
84 	}
85 	if (report->field[0]->report_count < 7) {
86 		hid_err(hid, "not enough values in the field\n");
87 		return -ENODEV;
88 	}
89 
90 	lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
91 	if (!lg2ff)
92 		return -ENOMEM;
93 
94 	set_bit(FF_RUMBLE, dev->ffbit);
95 
96 	error = input_ff_create_memless(dev, lg2ff, play_effect);
97 	if (error) {
98 		kfree(lg2ff);
99 		return error;
100 	}
101 
102 	lg2ff->report = report;
103 	report->field[0]->value[0] = 0xf3;
104 	report->field[0]->value[1] = 0x00;
105 	report->field[0]->value[2] = 0x00;
106 	report->field[0]->value[3] = 0x00;
107 	report->field[0]->value[4] = 0x00;
108 	report->field[0]->value[5] = 0x00;
109 	report->field[0]->value[6] = 0x00;
110 
111 	usbhid_submit_report(hid, report, USB_DIR_OUT);
112 
113 	hid_info(hid, "Force feedback for Logitech RumblePad/Rumblepad 2 by Anssi Hannula <anssi.hannula@gmail.com>\n");
114 
115 	return 0;
116 }
117