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 
18 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
19 MODULE_DESCRIPTION("Input driver event debug module");
20 MODULE_LICENSE("GPL");
21 
evbug_event(struct input_handle * handle,unsigned int type,unsigned int code,int value)22 static 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 
evbug_connect(struct input_handler * handler,struct input_dev * dev,const struct input_device_id * id)28 static 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 
evbug_disconnect(struct input_handle * handle)64 static 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 
74 static const struct input_device_id evbug_ids[] = {
75 	{ .driver_info = 1 },	/* Matches all devices */
76 	{ },			/* Terminating zero entry */
77 };
78 
79 MODULE_DEVICE_TABLE(input, evbug_ids);
80 
81 static 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 
evbug_init(void)89 static int __init evbug_init(void)
90 {
91 	return input_register_handler(&evbug_handler);
92 }
93 
evbug_exit(void)94 static void __exit evbug_exit(void)
95 {
96 	input_unregister_handler(&evbug_handler);
97 }
98 
99 module_init(evbug_init);
100 module_exit(evbug_exit);
101