LXR linux/drivers/hid/hid-lg2ff.c

   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
  31struct lg2ff_device {
  32        struct hid_report *report;
  33};
  34
  35static 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
  62int 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