1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Vibration support for Mega World controllers 4 * 5 * Copyright 2022 Frank Zago 6 * 7 * Derived from hid-zpff.c: 8 * Copyright (c) 2005, 2006 Anssi Hannula <anssi.hannula@gmail.com> 9 */ 10 11 #include <linux/hid.h> 12 #include <linux/input.h> 13 #include <linux/module.h> 14 #include <linux/slab.h> 15 16 #include "hid-ids.h" 17 18 struct mwctrl_device { 19 struct hid_report *report; 20 s32 *weak; 21 s32 *strong; 22 }; 23 24 static int mwctrl_play(struct input_dev *dev, void *data, 25 struct ff_effect *effect) 26 { 27 struct hid_device *hid = input_get_drvdata(dev); 28 struct mwctrl_device *mwctrl = data; 29 30 *mwctrl->strong = effect->u.rumble.strong_magnitude >> 8; 31 *mwctrl->weak = effect->u.rumble.weak_magnitude >> 8; 32 33 hid_hw_request(hid, mwctrl->report, HID_REQ_SET_REPORT); 34 35 return 0; 36 } 37 38 static int mwctrl_init(struct hid_device *hid) 39 { 40 struct mwctrl_device *mwctrl; 41 struct hid_report *report; 42 struct hid_input *hidinput; 43 struct input_dev *dev; 44 int error; 45 int i; 46 47 if (list_empty(&hid->inputs)) { 48 hid_err(hid, "no inputs found\n"); 49 return -ENODEV; 50 } 51 hidinput = list_entry(hid->inputs.next, struct hid_input, list); 52 dev = hidinput->input; 53 54 for (i = 0; i < 4; i++) { 55 report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, i, 1); 56 if (!report) 57 return -ENODEV; 58 } 59 60 mwctrl = kzalloc(sizeof(struct mwctrl_device), GFP_KERNEL); 61 if (!mwctrl) 62 return -ENOMEM; 63 64 set_bit(FF_RUMBLE, dev->ffbit); 65 66 error = input_ff_create_memless(dev, mwctrl, mwctrl_play); 67 if (error) { 68 kfree(mwctrl); 69 return error; 70 } 71 72 mwctrl->report = report; 73 74 /* Field 0 is always 2, and field 1 is always 0. The original 75 * windows driver has a 5 bytes command, where the 5th byte is 76 * a repeat of the 3rd byte, however the device has only 4 77 * fields. It could be a bug in the driver, or there is a 78 * different device that needs it. 79 */ 80 report->field[0]->value[0] = 0x02; 81 82 mwctrl->strong = &report->field[2]->value[0]; 83 mwctrl->weak = &report->field[3]->value[0]; 84 85 return 0; 86 } 87 88 static int mwctrl_probe(struct hid_device *hdev, const struct hid_device_id *id) 89 { 90 int ret; 91 92 ret = hid_parse(hdev); 93 if (ret) { 94 hid_err(hdev, "parse failed\n"); 95 return ret; 96 } 97 98 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF); 99 if (ret) { 100 hid_err(hdev, "hw start failed\n"); 101 return ret; 102 } 103 104 ret = mwctrl_init(hdev); 105 if (ret) 106 hid_hw_stop(hdev); 107 108 return ret; 109 } 110 111 static const struct hid_device_id mwctrl_devices[] = { 112 { HID_USB_DEVICE(USB_VENDOR_MEGAWORLD, 113 USB_DEVICE_ID_MEGAWORLD_GAMEPAD) }, 114 { } 115 }; 116 MODULE_DEVICE_TABLE(hid, mwctrl_devices); 117 118 static struct hid_driver mwctrl_driver = { 119 .name = "megaworld", 120 .id_table = mwctrl_devices, 121 .probe = mwctrl_probe, 122 }; 123 module_hid_driver(mwctrl_driver); 124 125 MODULE_LICENSE("GPL"); 126