summaryrefslogtreecommitdiff
path: root/drivers/input/misc/regulator-haptic.c
blob: a1db1e5040dcf13937e54199f7d8d696885f90a4 (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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
/*
 * Regulator haptic driver
 *
 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
 * Author: Jaewon Kim <jaewon02.kim@samsung.com>
 * Author: Hyunhee Kim <hyunhee.kim@samsung.com>
 *
 * 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/input.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_data/regulator-haptic.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>

#define MAX_MAGNITUDE_SHIFT	16

struct regulator_haptic {
	struct device *dev;
	struct input_dev *input_dev;
	struct regulator *regulator;

	struct work_struct work;
	struct mutex mutex;

	bool active;
	bool suspended;

	unsigned int max_volt;
	unsigned int min_volt;
	unsigned int magnitude;
};

static int regulator_haptic_toggle(struct regulator_haptic *haptic, bool on)
{
	int error;

	if (haptic->active != on) {

		error = on ? regulator_enable(haptic->regulator) :
			     regulator_disable(haptic->regulator);
		if (error) {
			dev_err(haptic->dev,
				"failed to switch regulator %s: %d\n",
				on ? "on" : "off", error);
			return error;
		}

		haptic->active = on;
	}

	return 0;
}

static int regulator_haptic_set_voltage(struct regulator_haptic *haptic,
					 unsigned int magnitude)
{
	u64 volt_mag_multi;
	unsigned int intensity;
	int error;

	volt_mag_multi = (u64)(haptic->max_volt - haptic->min_volt) * magnitude;
	intensity = (unsigned int)(volt_mag_multi >> MAX_MAGNITUDE_SHIFT);

	error = regulator_set_voltage(haptic->regulator,
				      intensity + haptic->min_volt,
				      haptic->max_volt);
	if (error) {
		dev_err(haptic->dev, "cannot set regulator voltage to %d: %d\n",
			intensity + haptic->min_volt, error);
		return error;
	}

	regulator_haptic_toggle(haptic, !!magnitude);

	return 0;
}

static void regulator_haptic_work(struct work_struct *work)
{
	struct regulator_haptic *haptic = container_of(work,
					struct regulator_haptic, work);

	mutex_lock(&haptic->mutex);

	if (!haptic->suspended)
		regulator_haptic_set_voltage(haptic, haptic->magnitude);

	mutex_unlock(&haptic->mutex);
}

static int regulator_haptic_play_effect(struct input_dev *input, void *data,
					struct ff_effect *effect)
{
	struct regulator_haptic *haptic = input_get_drvdata(input);

	haptic->magnitude = effect->u.rumble.strong_magnitude;
	if (!haptic->magnitude)
		haptic->magnitude = effect->u.rumble.weak_magnitude;

	schedule_work(&haptic->work);

	return 0;
}

static void regulator_haptic_close(struct input_dev *input)
{
	struct regulator_haptic *haptic = input_get_drvdata(input);

	cancel_work_sync(&haptic->work);
	regulator_haptic_set_voltage(haptic, 0);
}

static int __maybe_unused
regulator_haptic_parse_dt(struct device *dev, struct regulator_haptic *haptic)
{
	struct device_node *node;
	int error;

	node = dev->of_node;
	if(!node) {
		dev_err(dev, "Missing device tree data\n");
		return -EINVAL;
	}

	error = of_property_read_u32(node, "max-microvolt", &haptic->max_volt);
	if (error) {
		dev_err(dev, "cannot parse max-microvolt\n");
		return error;
	}

	error = of_property_read_u32(node, "min-microvolt", &haptic->min_volt);
	if (error) {
		dev_err(dev, "cannot parse min-microvolt\n");
		return error;
	}

	return 0;
}

static int regulator_haptic_probe(struct platform_device *pdev)
{
	const struct regulator_haptic_data *pdata = dev_get_platdata(&pdev->dev);
	struct regulator_haptic *haptic;
	struct input_dev *input_dev;
	int error;

	haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
	if (!haptic)
		return -ENOMEM;

	platform_set_drvdata(pdev, haptic);
	haptic->dev = &pdev->dev;
	mutex_init(&haptic->mutex);
	INIT_WORK(&haptic->work, regulator_haptic_work);

	if (pdata) {
		haptic->max_volt = pdata->max_volt;
		haptic->min_volt = pdata->min_volt;
	} else if (IS_ENABLED(CONFIG_OF)) {
		error = regulator_haptic_parse_dt(&pdev->dev, haptic);
		if (error)
			return error;
	} else {
		dev_err(&pdev->dev, "Missing platform data\n");
		return -EINVAL;
	}

	haptic->regulator = devm_regulator_get_exclusive(&pdev->dev, "haptic");
	if (IS_ERR(haptic->regulator)) {
		dev_err(&pdev->dev, "failed to get regulator\n");
		return PTR_ERR(haptic->regulator);
	}

	input_dev = devm_input_allocate_device(&pdev->dev);
	if (!input_dev)
		return	-ENOMEM;

	haptic->input_dev = input_dev;
	haptic->input_dev->name = "regulator-haptic";
	haptic->input_dev->dev.parent = &pdev->dev;
	haptic->input_dev->close = regulator_haptic_close;
	input_set_drvdata(haptic->input_dev, haptic);
	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);

	error = input_ff_create_memless(input_dev, NULL,
					regulator_haptic_play_effect);
	if (error) {
		dev_err(&pdev->dev, "failed to create force-feedback\n");
		return error;
	}

	error = input_register_device(haptic->input_dev);
	if (error) {
		dev_err(&pdev->dev, "failed to register input device\n");
		return error;
	}

	return 0;
}

static int __maybe_unused regulator_haptic_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
	int error;

	error = mutex_lock_interruptible(&haptic->mutex);
	if (error)
		return error;

	regulator_haptic_set_voltage(haptic, 0);

	haptic->suspended = true;

	mutex_unlock(&haptic->mutex);

	return 0;
}

static int __maybe_unused regulator_haptic_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
	unsigned int magnitude;

	mutex_lock(&haptic->mutex);

	haptic->suspended = false;

	magnitude = READ_ONCE(haptic->magnitude);
	if (magnitude)
		regulator_haptic_set_voltage(haptic, magnitude);

	mutex_unlock(&haptic->mutex);

	return 0;
}

static SIMPLE_DEV_PM_OPS(regulator_haptic_pm_ops,
		regulator_haptic_suspend, regulator_haptic_resume);

static const struct of_device_id regulator_haptic_dt_match[] = {
	{ .compatible = "regulator-haptic" },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, regulator_haptic_dt_match);

static struct platform_driver regulator_haptic_driver = {
	.probe		= regulator_haptic_probe,
	.driver		= {
		.name		= "regulator-haptic",
		.of_match_table = regulator_haptic_dt_match,
		.pm		= &regulator_haptic_pm_ops,
	},
};
module_platform_driver(regulator_haptic_driver);

MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
MODULE_DESCRIPTION("Regulator haptic driver");
MODULE_LICENSE("GPL");