1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Force feedback support for Logitech RumblePad and Rumblepad 2 4 * 5 * Copyright (c) 2008 Anssi Hannula <anssi.hannula@gmail.com> 6 */ 7 8 /* 9 */ 10 11 12 #include <linux/input.h> 13 #include <linux/slab.h> 14 #include <linux/hid.h> 15 16 #include "hid-lg.h" 17 18 struct lg2ff_device { 19 struct hid_report *report; 20 }; 21 22 static int play_effect(struct input_dev *dev, void *data, 23 struct ff_effect *effect) 24 { 25 struct hid_device *hid = input_get_drvdata(dev); 26 struct lg2ff_device *lg2ff = data; 27 int weak, strong; 28 29 strong = effect->u.rumble.strong_magnitude; 30 weak = effect->u.rumble.weak_magnitude; 31 32 if (weak || strong) { 33 weak = weak * 0xff / 0xffff; 34 strong = strong * 0xff / 0xffff; 35 36 lg2ff->report->field[0]->value[0] = 0x51; 37 lg2ff->report->field[0]->value[2] = weak; 38 lg2ff->report->field[0]->value[4] = strong; 39 } else { 40 lg2ff->report->field[0]->value[0] = 0xf3; 41 lg2ff->report->field[0]->value[2] = 0x00; 42 lg2ff->report->field[0]->value[4] = 0x00; 43 } 44 45 hid_hw_request(hid, lg2ff->report, HID_REQ_SET_REPORT); 46 return 0; 47 } 48 49 int lg2ff_init(struct hid_device *hid) 50 { 51 struct lg2ff_device *lg2ff; 52 struct hid_report *report; 53 struct hid_input *hidinput; 54 struct input_dev *dev; 55 int error; 56 57 if (list_empty(&hid->inputs)) { 58 hid_err(hid, "no inputs found\n"); 59 return -ENODEV; 60 } 61 hidinput = list_entry(hid->inputs.next, struct hid_input, list); 62 dev = hidinput->input; 63 64 /* Check that the report looks ok */ 65 report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7); 66 if (!report) 67 return -ENODEV; 68 69 lg2ff = kmalloc(sizeof(struct lg2ff_device), GFP_KERNEL); 70 if (!lg2ff) 71 return -ENOMEM; 72 73 set_bit(FF_RUMBLE, dev->ffbit); 74 75 error = input_ff_create_memless(dev, lg2ff, play_effect); 76 if (error) { 77 kfree(lg2ff); 78 return error; 79 } 80 81 lg2ff->report = report; 82 report->field[0]->value[0] = 0xf3; 83 report->field[0]->value[1] = 0x00; 84 report->field[0]->value[2] = 0x00; 85 report->field[0]->value[3] = 0x00; 86 report->field[0]->value[4] = 0x00; 87 report->field[0]->value[5] = 0x00; 88 report->field[0]->value[6] = 0x00; 89 90 hid_hw_request(hid, report, HID_REQ_SET_REPORT); 91 92 hid_info(hid, "Force feedback for Logitech variant 2 rumble devices by Anssi Hannula <anssi.hannula@gmail.com>\n"); 93 94 return 0; 95 } 96