xref: /linux/drivers/hid/hid-megaworld.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
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_input_configured(struct hid_device *hid, struct hid_input *hidinput)
39 {
40 	struct mwctrl_device *mwctrl;
41 	struct hid_report *report;
42 	struct input_dev *dev = hidinput->input;
43 	int error;
44 	int i;
45 
46 	if (!list_is_first(&hidinput->list, &hid->inputs))
47 		return 0;
48 
49 	for (i = 0; i < 4; i++) {
50 		report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, i, 1);
51 		if (!report)
52 			return -ENODEV;
53 	}
54 
55 	mwctrl = kzalloc_obj(struct mwctrl_device);
56 	if (!mwctrl)
57 		return -ENOMEM;
58 
59 	mwctrl->report = report;
60 	/* Field 0 is always 2, and field 1 is always 0. The original
61 	 * windows driver has a 5 bytes command, where the 5th byte is
62 	 * a repeat of the 3rd byte, however the device has only 4
63 	 * fields. It could be a bug in the driver, or there is a
64 	 * different device that needs it.
65 	 */
66 	report->field[0]->value[0] = 0x02;
67 
68 	mwctrl->strong = &report->field[2]->value[0];
69 	mwctrl->weak = &report->field[3]->value[0];
70 
71 	set_bit(FF_RUMBLE, dev->ffbit);
72 
73 	error = input_ff_create_memless(dev, mwctrl, mwctrl_play);
74 	if (error) {
75 		kfree(mwctrl);
76 		return error;
77 	}
78 
79 	return 0;
80 }
81 
82 static const struct hid_device_id mwctrl_devices[] = {
83 	{ HID_USB_DEVICE(USB_VENDOR_MEGAWORLD,
84 			 USB_DEVICE_ID_MEGAWORLD_GAMEPAD) },
85 	{ }
86 };
87 MODULE_DEVICE_TABLE(hid, mwctrl_devices);
88 
89 static struct hid_driver mwctrl_driver = {
90 	.name = "megaworld",
91 	.id_table = mwctrl_devices,
92 	.input_configured = mwctrl_input_configured,
93 };
94 module_hid_driver(mwctrl_driver);
95 
96 MODULE_DESCRIPTION("Vibration support for Mega World controllers");
97 MODULE_LICENSE("GPL");
98