1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 1999-2001 Vojtech Pavlik
4 */
5
6/*
7 *  Input driver event debug module - dumps all events into syslog
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/input.h>
15#include <linux/init.h>
16#include <linux/device.h>
17
18MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
19MODULE_DESCRIPTION("Input driver event debug module");
20MODULE_LICENSE("GPL");
21
22static void evbug_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
23{
24	printk(KERN_DEBUG pr_fmt("Event. Dev: %s, Type: %d, Code: %d, Value: %d\n"),
25	       dev_name(&handle->dev->dev), type, code, value);
26}
27
28static int evbug_connect(struct input_handler *handler, struct input_dev *dev,
29			 const struct input_device_id *id)
30{
31	struct input_handle *handle;
32	int error;
33
34	handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
35	if (!handle)
36		return -ENOMEM;
37
38	handle->dev = dev;
39	handle->handler = handler;
40	handle->name = "evbug";
41
42	error = input_register_handle(handle);
43	if (error)
44		goto err_free_handle;
45
46	error = input_open_device(handle);
47	if (error)
48		goto err_unregister_handle;
49
50	printk(KERN_DEBUG pr_fmt("Connected device: %s (%s at %s)\n"),
51	       dev_name(&dev->dev),
52	       dev->name ?: "unknown",
53	       dev->phys ?: "unknown");
54
55	return 0;
56
57 err_unregister_handle:
58	input_unregister_handle(handle);
59 err_free_handle:
60	kfree(handle);
61	return error;
62}
63
64static void evbug_disconnect(struct input_handle *handle)
65{
66	printk(KERN_DEBUG pr_fmt("Disconnected device: %s\n"),
67	       dev_name(&handle->dev->dev));
68
69	input_close_device(handle);
70	input_unregister_handle(handle);
71	kfree(handle);
72}
73
74static const struct input_device_id evbug_ids[] = {
75	{ .driver_info = 1 },	/* Matches all devices */
76	{ },			/* Terminating zero entry */
77};
78
79MODULE_DEVICE_TABLE(input, evbug_ids);
80
81static struct input_handler evbug_handler = {
82	.event =	evbug_event,
83	.connect =	evbug_connect,
84	.disconnect =	evbug_disconnect,
85	.name =		"evbug",
86	.id_table =	evbug_ids,
87};
88
89static int __init evbug_init(void)
90{
91	return input_register_handler(&evbug_handler);
92}
93
94static void __exit evbug_exit(void)
95{
96	input_unregister_handler(&evbug_handler);
97}
98
99module_init(evbug_init);
100module_exit(evbug_exit);
101