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