aboutsummaryrefslogtreecommitdiff
path: root/drivers/input/input-leds.c
blob: 074a65ed17bb4d595d2b48f13e0d2e03c2267bc6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
/*
 * LED support for the input layer
 *
 * Copyright 2010-2015 Samuel Thibault <samuel.thibault@ens-lyon.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/input.h>

#if IS_ENABLED(CONFIG_VT)
#define VT_TRIGGER(_name)	.trigger = _name
#else
#define VT_TRIGGER(_name)	.trigger = NULL
#endif

static const struct {
	const char *name;
	const char *trigger;
} input_led_info[LED_CNT] = {
	[LED_NUML]	= { "numlock", VT_TRIGGER("kbd-numlock") },
	[LED_CAPSL]	= { "capslock", VT_TRIGGER("kbd-capslock") },
	[LED_SCROLLL]	= { "scrolllock", VT_TRIGGER("kbd-scrolllock") },
	[LED_COMPOSE]	= { "compose" },
	[LED_KANA]	= { "kana", VT_TRIGGER("kbd-kanalock") },
	[LED_SLEEP]	= { "sleep" } ,
	[LED_SUSPEND]	= { "suspend" },
	[LED_MUTE]	= { "mute" },
	[LED_MISC]	= { "misc" },
	[LED_MAIL]	= { "mail" },
	[LED_CHARGING]	= { "charging" },
};

struct input_led {
	struct led_classdev cdev;
	struct input_handle *handle;
	unsigned int code; /* One of LED_* constants */
};

struct input_leds {
	struct input_handle handle;
	unsigned int num_leds;
	struct input_led leds[];
};

static enum led_brightness input_leds_brightness_get(struct led_classdev *cdev)
{
	struct input_led *led = container_of(cdev, struct input_led, cdev);
	struct input_dev *input = led->handle->dev;

	return test_bit(led->code, input->led) ? cdev->max_brightness : 0;
}

static void input_leds_brightness_set(struct led_classdev *cdev,
				      enum led_brightness brightness)
{
	struct input_led *led = container_of(cdev, struct input_led, cdev);

	input_inject_event(led->handle, EV_LED, led->code, !!brightness);
}

static void input_leds_event(struct input_handle *handle, unsigned int type,
			     unsigned int code, int value)
{
}

static int input_leds_connect(struct input_handler *handler,
			      struct input_dev *dev,
			      const struct input_device_id *id)
{
	struct input_leds *leds;
	unsigned int num_leds;
	unsigned int led_code;
	int led_no;
	int error;

	num_leds = bitmap_weight(dev->ledbit, LED_CNT);
	if (!num_leds)
		return -ENXIO;

	leds = kzalloc(sizeof(*leds) + num_leds * sizeof(*leds->leds),
		       GFP_KERNEL);
	if (!leds)
		return -ENOMEM;

	leds->num_leds = num_leds;

	leds->handle.dev = dev;
	leds->handle.handler = handler;
	leds->handle.name = "leds";
	leds->handle.private = leds;

	error = input_register_handle(&leds->handle);
	if (error)
		goto err_free_mem;

	error = input_open_device(&leds->handle);
	if (error)
		goto err_unregister_handle;

	led_no = 0;
	for_each_set_bit(led_code, dev->ledbit, LED_CNT) {
		struct input_led *led = &leds->leds[led_no];

		led->handle = &leds->handle;
		led->code = led_code;

		if (WARN_ON(!input_led_info[led_code].name))
			continue;

		led->cdev.name = kasprintf(GFP_KERNEL, "%s::%s",
					   dev_name(&dev->dev),
					   input_led_info[led_code].name);
		if (!led->cdev.name) {
			error = -ENOMEM;
			goto err_unregister_leds;
		}

		led->cdev.max_brightness = 1;
		led->cdev.brightness_get = input_leds_brightness_get;
		led->cdev.brightness_set = input_leds_brightness_set;
		led->cdev.default_trigger = input_led_info[led_code].trigger;

		error = led_classdev_register(&dev->dev, &led->cdev);
		if (error) {
			dev_err(&dev->dev, "failed to register LED %s: %d\n",
				led->cdev.name, error);
			kfree(led->cdev.name);
			goto err_unregister_leds;
		}

		led_no++;
	}

	return 0;

err_unregister_leds:
	while (--led_no >= 0) {
		struct input_led *led = &leds->leds[led_no];

		led_classdev_unregister(&led->cdev);
		kfree(led->cdev.name);
	}

	input_close_device(&leds->handle);

err_unregister_handle:
	input_unregister_handle(&leds->handle);

err_free_mem:
	kfree(leds);
	return error;
}

static void input_leds_disconnect(struct input_handle *handle)
{
	struct input_leds *leds = handle->private;
	int i;

	for (i = 0; i < leds->num_leds; i++) {
		struct input_led *led = &leds->leds[i];

		led_classdev_unregister(&led->cdev);
		kfree(led->cdev.name);
	}

	input_close_device(handle);
	input_unregister_handle(handle);

	kfree(leds);
}

static const struct input_device_id input_leds_ids[] = {
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT,
		.evbit = { BIT_MASK(EV_LED) },
	},
	{ },
};
MODULE_DEVICE_TABLE(input, input_leds_ids);

static struct input_handler input_leds_handler = {
	.event =	input_leds_event,
	.connect =	input_leds_connect,
	.disconnect =	input_leds_disconnect,
	.name =		"leds",
	.id_table =	input_leds_ids,
};

static int __init input_leds_init(void)
{
	return input_register_handler(&input_leds_handler);
}
module_init(input_leds_init);

static void __exit input_leds_exit(void)
{
	input_unregister_handler(&input_leds_handler);
}
module_exit(input_leds_exit);

MODULE_AUTHOR("Samuel Thibault <samuel.thibault@ens-lyon.org>");
MODULE_AUTHOR("Dmitry Torokhov <dmitry.torokhov@gmail.com>");
MODULE_DESCRIPTION("Input -> LEDs Bridge");
MODULE_LICENSE("GPL v2");