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hid-lg2ff.c
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1 /*
2  * Force feedback support for Logitech RumblePad and Rumblepad 2
3  *
4  * Copyright (c) 2008 Anssi Hannula <[email protected]>
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 
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 <[email protected]>\n");
114 
115  return 0;
116 }