xref: /openbmc/linux/drivers/hid/hid-lg2ff.c (revision ecba1060)
1 /*
2  *  Force feedback support for Logitech 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/usb.h>
26 #include <linux/hid.h>
27 
28 #include "usbhid/usbhid.h"
29 #include "hid-lg.h"
30 
31 struct lg2ff_device {
32 	struct hid_report *report;
33 };
34 
35 static int play_effect(struct input_dev *dev, void *data,
36 			 struct ff_effect *effect)
37 {
38 	struct hid_device *hid = input_get_drvdata(dev);
39 	struct lg2ff_device *lg2ff = data;
40 	int weak, strong;
41 
42 	strong = effect->u.rumble.strong_magnitude;
43 	weak = effect->u.rumble.weak_magnitude;
44 
45 	if (weak || strong) {
46 		weak = weak * 0xff / 0xffff;
47 		strong = strong * 0xff / 0xffff;
48 
49 		lg2ff->report->field[0]->value[0] = 0x51;
50 		lg2ff->report->field[0]->value[2] = weak;
51 		lg2ff->report->field[0]->value[4] = strong;
52 	} else {
53 		lg2ff->report->field[0]->value[0] = 0xf3;
54 		lg2ff->report->field[0]->value[2] = 0x00;
55 		lg2ff->report->field[0]->value[4] = 0x00;
56 	}
57 
58 	usbhid_submit_report(hid, lg2ff->report, USB_DIR_OUT);
59 	return 0;
60 }
61 
62 int lg2ff_init(struct hid_device *hid)
63 {
64 	struct lg2ff_device *lg2ff;
65 	struct hid_report *report;
66 	struct hid_input *hidinput = list_entry(hid->inputs.next,
67 						struct hid_input, list);
68 	struct list_head *report_list =
69 			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
70 	struct input_dev *dev = hidinput->input;
71 	int error;
72 
73 	if (list_empty(report_list)) {
74 		dev_err(&hid->dev, "no output report found\n");
75 		return -ENODEV;
76 	}
77 
78 	report = list_entry(report_list->next, struct hid_report, list);
79 
80 	if (report->maxfield < 1) {
81 		dev_err(&hid->dev, "output report is empty\n");
82 		return -ENODEV;
83 	}
84 	if (report->field[0]->report_count < 7) {
85 		dev_err(&hid->dev, "not enough values in the field\n");
86 		return -ENODEV;
87 	}
88 
89 	lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL);
90 	if (!lg2ff)
91 		return -ENOMEM;
92 
93 	set_bit(FF_RUMBLE, dev->ffbit);
94 
95 	error = input_ff_create_memless(dev, lg2ff, play_effect);
96 	if (error) {
97 		kfree(lg2ff);
98 		return error;
99 	}
100 
101 	lg2ff->report = report;
102 	report->field[0]->value[0] = 0xf3;
103 	report->field[0]->value[1] = 0x00;
104 	report->field[0]->value[2] = 0x00;
105 	report->field[0]->value[3] = 0x00;
106 	report->field[0]->value[4] = 0x00;
107 	report->field[0]->value[5] = 0x00;
108 	report->field[0]->value[6] = 0x00;
109 
110 	usbhid_submit_report(hid, report, USB_DIR_OUT);
111 
112 	dev_info(&hid->dev, "Force feedback for Logitech Rumblepad 2 by "
113 	       "Anssi Hannula <anssi.hannula@gmail.com>\n");
114 
115 	return 0;
116 }
117