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/usb.h> 27 28 #include "hid-ids.h" 29 #include "usbhid/usbhid.h" 30 31 struct emsff_device { 32 struct hid_report *report; 33 }; 34 35 static int emsff_play(struct input_dev *dev, void *data, 36 struct ff_effect *effect) 37 { 38 struct hid_device *hid = input_get_drvdata(dev); 39 struct emsff_device *emsff = data; 40 int weak, strong; 41 42 weak = effect->u.rumble.weak_magnitude; 43 strong = effect->u.rumble.strong_magnitude; 44 45 dbg_hid("called with 0x%04x 0x%04x\n", strong, weak); 46 47 weak = weak * 0xff / 0xffff; 48 strong = strong * 0xff / 0xffff; 49 50 emsff->report->field[0]->value[1] = weak; 51 emsff->report->field[0]->value[2] = strong; 52 53 dbg_hid("running with 0x%02x 0x%02x\n", strong, weak); 54 usbhid_submit_report(hid, emsff->report, USB_DIR_OUT); 55 56 return 0; 57 } 58 59 static int emsff_init(struct hid_device *hid) 60 { 61 struct emsff_device *emsff; 62 struct hid_report *report; 63 struct hid_input *hidinput = list_first_entry(&hid->inputs, 64 struct hid_input, list); 65 struct list_head *report_list = 66 &hid->report_enum[HID_OUTPUT_REPORT].report_list; 67 struct input_dev *dev = hidinput->input; 68 int error; 69 70 if (list_empty(report_list)) { 71 hid_err(hid, "no output reports found\n"); 72 return -ENODEV; 73 } 74 75 report = list_first_entry(report_list, struct hid_report, list); 76 if (report->maxfield < 1) { 77 hid_err(hid, "no fields in the report\n"); 78 return -ENODEV; 79 } 80 81 if (report->field[0]->report_count < 7) { 82 hid_err(hid, "not enough values in the field\n"); 83 return -ENODEV; 84 } 85 86 emsff = kzalloc(sizeof(struct emsff_device), GFP_KERNEL); 87 if (!emsff) 88 return -ENOMEM; 89 90 set_bit(FF_RUMBLE, dev->ffbit); 91 92 error = input_ff_create_memless(dev, emsff, emsff_play); 93 if (error) { 94 kfree(emsff); 95 return error; 96 } 97 98 emsff->report = report; 99 emsff->report->field[0]->value[0] = 0x01; 100 emsff->report->field[0]->value[1] = 0x00; 101 emsff->report->field[0]->value[2] = 0x00; 102 emsff->report->field[0]->value[3] = 0x00; 103 emsff->report->field[0]->value[4] = 0x00; 104 emsff->report->field[0]->value[5] = 0x00; 105 emsff->report->field[0]->value[6] = 0x00; 106 usbhid_submit_report(hid, emsff->report, USB_DIR_OUT); 107 108 hid_info(hid, "force feedback for EMS based devices by Ignaz Forster <ignaz.forster@gmx.de>\n"); 109 110 return 0; 111 } 112 113 static int ems_probe(struct hid_device *hdev, const struct hid_device_id *id) 114 { 115 int ret; 116 117 ret = hid_parse(hdev); 118 if (ret) { 119 hid_err(hdev, "parse failed\n"); 120 goto err; 121 } 122 123 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF); 124 if (ret) { 125 hid_err(hdev, "hw start failed\n"); 126 goto err; 127 } 128 129 emsff_init(hdev); 130 131 return 0; 132 err: 133 return ret; 134 } 135 136 static const struct hid_device_id ems_devices[] = { 137 { HID_USB_DEVICE(USB_VENDOR_ID_EMS, 0x118) }, 138 { } 139 }; 140 MODULE_DEVICE_TABLE(hid, ems_devices); 141 142 static struct hid_driver ems_driver = { 143 .name = "hkems", 144 .id_table = ems_devices, 145 .probe = ems_probe, 146 }; 147 148 static int ems_init(void) 149 { 150 return hid_register_driver(&ems_driver); 151 } 152 153 static void ems_exit(void) 154 { 155 hid_unregister_driver(&ems_driver); 156 } 157 158 module_init(ems_init); 159 module_exit(ems_exit); 160 MODULE_LICENSE("GPL"); 161 162