drivers/hid/hid-lg2ff.c

   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;
  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 }