1 /* 2 * Force feedback support for EMS Trio Linker Plus II 3 * 4 * Copyright (c) 2010 Ignaz Forster <ignaz.forster@gmx.de> 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/hid.h> 25 #include <linux/input.h> 26 #include <linux/module.h> 27 28 #include "hid-ids.h" 29 30 struct emsff_device { 31 struct hid_report *report; 32 }; 33 34 static int emsff_play(struct input_dev *dev, void *data, 35 struct ff_effect *effect) 36 { 37 struct hid_device *hid = input_get_drvdata(dev); 38 struct emsff_device *emsff = data; 39 int weak, strong; 40 41 weak = effect->u.rumble.weak_magnitude; 42 strong = effect->u.rumble.strong_magnitude; 43 44 dbg_hid("called with 0x%04x 0x%04x\n", strong, weak); 45 46 weak = weak * 0xff / 0xffff; 47 strong = strong * 0xff / 0xffff; 48 49 emsff->report->field[0]->value[1] = weak; 50 emsff->report->field[0]->value[2] = strong; 51 52 dbg_hid("running with 0x%02x 0x%02x\n", strong, weak); 53 hid_hw_request(hid, emsff->report, HID_REQ_SET_REPORT); 54 55 return 0; 56 } 57 58 static int emsff_init(struct hid_device *hid) 59 { 60 struct emsff_device *emsff; 61 struct hid_report *report; 62 struct hid_input *hidinput = list_first_entry(&hid->inputs, 63 struct hid_input, list); 64 struct list_head *report_list = 65 &hid->report_enum[HID_OUTPUT_REPORT].report_list; 66 struct input_dev *dev = hidinput->input; 67 int error; 68 69 if (list_empty(report_list)) { 70 hid_err(hid, "no output reports found\n"); 71 return -ENODEV; 72 } 73 74 report = list_first_entry(report_list, struct hid_report, list); 75 if (report->maxfield < 1) { 76 hid_err(hid, "no fields in the report\n"); 77 return -ENODEV; 78 } 79 80 if (report->field[0]->report_count < 7) { 81 hid_err(hid, "not enough values in the field\n"); 82 return -ENODEV; 83 } 84 85 emsff = kzalloc(sizeof(struct emsff_device), GFP_KERNEL); 86 if (!emsff) 87 return -ENOMEM; 88 89 set_bit(FF_RUMBLE, dev->ffbit); 90 91 error = input_ff_create_memless(dev, emsff, emsff_play); 92 if (error) { 93 kfree(emsff); 94 return error; 95 } 96 97 emsff->report = report; 98 emsff->report->field[0]->value[0] = 0x01; 99 emsff->report->field[0]->value[1] = 0x00; 100 emsff->report->field[0]->value[2] = 0x00; 101 emsff->report->field[0]->value[3] = 0x00; 102 emsff->report->field[0]->value[4] = 0x00; 103 emsff->report->field[0]->value[5] = 0x00; 104 emsff->report->field[0]->value[6] = 0x00; 105 hid_hw_request(hid, emsff->report, HID_REQ_SET_REPORT); 106 107 hid_info(hid, "force feedback for EMS based devices by Ignaz Forster <ignaz.forster@gmx.de>\n"); 108 109 return 0; 110 } 111 112 static int ems_probe(struct hid_device *hdev, const struct hid_device_id *id) 113 { 114 int ret; 115 116 ret = hid_parse(hdev); 117 if (ret) { 118 hid_err(hdev, "parse failed\n"); 119 goto err; 120 } 121 122 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF); 123 if (ret) { 124 hid_err(hdev, "hw start failed\n"); 125 goto err; 126 } 127 128 ret = emsff_init(hdev); 129 if (ret) { 130 dev_err(&hdev->dev, "force feedback init failed\n"); 131 hid_hw_stop(hdev); 132 goto err; 133 } 134 135 return 0; 136 err: 137 return ret; 138 } 139 140 static const struct hid_device_id ems_devices[] = { 141 { HID_USB_DEVICE(USB_VENDOR_ID_EMS, USB_DEVICE_ID_EMS_TRIO_LINKER_PLUS_II) }, 142 { } 143 }; 144 MODULE_DEVICE_TABLE(hid, ems_devices); 145 146 static struct hid_driver ems_driver = { 147 .name = "hkems", 148 .id_table = ems_devices, 149 .probe = ems_probe, 150 }; 151 module_hid_driver(ems_driver); 152 153 MODULE_LICENSE("GPL"); 154 155