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10#include <linux/input.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/platform_data/regulator-haptic.h>
14#include <linux/platform_device.h>
15#include <linux/regulator/consumer.h>
16#include <linux/slab.h>
17
18#define MAX_MAGNITUDE_SHIFT 16
19
20struct regulator_haptic {
21 struct device *dev;
22 struct input_dev *input_dev;
23 struct regulator *regulator;
24
25 struct work_struct work;
26 struct mutex mutex;
27
28 bool active;
29 bool suspended;
30
31 unsigned int max_volt;
32 unsigned int min_volt;
33 unsigned int magnitude;
34};
35
36static int regulator_haptic_toggle(struct regulator_haptic *haptic, bool on)
37{
38 int error;
39
40 if (haptic->active != on) {
41
42 error = on ? regulator_enable(haptic->regulator) :
43 regulator_disable(haptic->regulator);
44 if (error) {
45 dev_err(haptic->dev,
46 "failed to switch regulator %s: %d\n",
47 on ? "on" : "off", error);
48 return error;
49 }
50
51 haptic->active = on;
52 }
53
54 return 0;
55}
56
57static int regulator_haptic_set_voltage(struct regulator_haptic *haptic,
58 unsigned int magnitude)
59{
60 u64 volt_mag_multi;
61 unsigned int intensity;
62 int error;
63
64 volt_mag_multi = (u64)(haptic->max_volt - haptic->min_volt) * magnitude;
65 intensity = (unsigned int)(volt_mag_multi >> MAX_MAGNITUDE_SHIFT);
66
67 error = regulator_set_voltage(haptic->regulator,
68 intensity + haptic->min_volt,
69 haptic->max_volt);
70 if (error) {
71 dev_err(haptic->dev, "cannot set regulator voltage to %d: %d\n",
72 intensity + haptic->min_volt, error);
73 return error;
74 }
75
76 regulator_haptic_toggle(haptic, !!magnitude);
77
78 return 0;
79}
80
81static void regulator_haptic_work(struct work_struct *work)
82{
83 struct regulator_haptic *haptic = container_of(work,
84 struct regulator_haptic, work);
85
86 mutex_lock(&haptic->mutex);
87
88 if (!haptic->suspended)
89 regulator_haptic_set_voltage(haptic, haptic->magnitude);
90
91 mutex_unlock(&haptic->mutex);
92}
93
94static int regulator_haptic_play_effect(struct input_dev *input, void *data,
95 struct ff_effect *effect)
96{
97 struct regulator_haptic *haptic = input_get_drvdata(input);
98
99 haptic->magnitude = effect->u.rumble.strong_magnitude;
100 if (!haptic->magnitude)
101 haptic->magnitude = effect->u.rumble.weak_magnitude;
102
103 schedule_work(&haptic->work);
104
105 return 0;
106}
107
108static void regulator_haptic_close(struct input_dev *input)
109{
110 struct regulator_haptic *haptic = input_get_drvdata(input);
111
112 cancel_work_sync(&haptic->work);
113 regulator_haptic_set_voltage(haptic, 0);
114}
115
116static int __maybe_unused
117regulator_haptic_parse_dt(struct device *dev, struct regulator_haptic *haptic)
118{
119 struct device_node *node;
120 int error;
121
122 node = dev->of_node;
123 if(!node) {
124 dev_err(dev, "Missing device tree data\n");
125 return -EINVAL;
126 }
127
128 error = of_property_read_u32(node, "max-microvolt", &haptic->max_volt);
129 if (error) {
130 dev_err(dev, "cannot parse max-microvolt\n");
131 return error;
132 }
133
134 error = of_property_read_u32(node, "min-microvolt", &haptic->min_volt);
135 if (error) {
136 dev_err(dev, "cannot parse min-microvolt\n");
137 return error;
138 }
139
140 return 0;
141}
142
143static int regulator_haptic_probe(struct platform_device *pdev)
144{
145 const struct regulator_haptic_data *pdata = dev_get_platdata(&pdev->dev);
146 struct regulator_haptic *haptic;
147 struct input_dev *input_dev;
148 int error;
149
150 haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
151 if (!haptic)
152 return -ENOMEM;
153
154 platform_set_drvdata(pdev, haptic);
155 haptic->dev = &pdev->dev;
156 mutex_init(&haptic->mutex);
157 INIT_WORK(&haptic->work, regulator_haptic_work);
158
159 if (pdata) {
160 haptic->max_volt = pdata->max_volt;
161 haptic->min_volt = pdata->min_volt;
162 } else if (IS_ENABLED(CONFIG_OF)) {
163 error = regulator_haptic_parse_dt(&pdev->dev, haptic);
164 if (error)
165 return error;
166 } else {
167 dev_err(&pdev->dev, "Missing platform data\n");
168 return -EINVAL;
169 }
170
171 haptic->regulator = devm_regulator_get_exclusive(&pdev->dev, "haptic");
172 if (IS_ERR(haptic->regulator)) {
173 dev_err(&pdev->dev, "failed to get regulator\n");
174 return PTR_ERR(haptic->regulator);
175 }
176
177 input_dev = devm_input_allocate_device(&pdev->dev);
178 if (!input_dev)
179 return -ENOMEM;
180
181 haptic->input_dev = input_dev;
182 haptic->input_dev->name = "regulator-haptic";
183 haptic->input_dev->dev.parent = &pdev->dev;
184 haptic->input_dev->close = regulator_haptic_close;
185 input_set_drvdata(haptic->input_dev, haptic);
186 input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
187
188 error = input_ff_create_memless(input_dev, NULL,
189 regulator_haptic_play_effect);
190 if (error) {
191 dev_err(&pdev->dev, "failed to create force-feedback\n");
192 return error;
193 }
194
195 error = input_register_device(haptic->input_dev);
196 if (error) {
197 dev_err(&pdev->dev, "failed to register input device\n");
198 return error;
199 }
200
201 return 0;
202}
203
204static int __maybe_unused regulator_haptic_suspend(struct device *dev)
205{
206 struct platform_device *pdev = to_platform_device(dev);
207 struct regulator_haptic *haptic = platform_get_drvdata(pdev);
208 int error;
209
210 error = mutex_lock_interruptible(&haptic->mutex);
211 if (error)
212 return error;
213
214 regulator_haptic_set_voltage(haptic, 0);
215
216 haptic->suspended = true;
217
218 mutex_unlock(&haptic->mutex);
219
220 return 0;
221}
222
223static int __maybe_unused regulator_haptic_resume(struct device *dev)
224{
225 struct platform_device *pdev = to_platform_device(dev);
226 struct regulator_haptic *haptic = platform_get_drvdata(pdev);
227 unsigned int magnitude;
228
229 mutex_lock(&haptic->mutex);
230
231 haptic->suspended = false;
232
233 magnitude = READ_ONCE(haptic->magnitude);
234 if (magnitude)
235 regulator_haptic_set_voltage(haptic, magnitude);
236
237 mutex_unlock(&haptic->mutex);
238
239 return 0;
240}
241
242static SIMPLE_DEV_PM_OPS(regulator_haptic_pm_ops,
243 regulator_haptic_suspend, regulator_haptic_resume);
244
245static const struct of_device_id regulator_haptic_dt_match[] = {
246 { .compatible = "regulator-haptic" },
247 { },
248};
249MODULE_DEVICE_TABLE(of, regulator_haptic_dt_match);
250
251static struct platform_driver regulator_haptic_driver = {
252 .probe = regulator_haptic_probe,
253 .driver = {
254 .name = "regulator-haptic",
255 .of_match_table = regulator_haptic_dt_match,
256 .pm = ®ulator_haptic_pm_ops,
257 },
258};
259module_platform_driver(regulator_haptic_driver);
260
261MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
262MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
263MODULE_DESCRIPTION("Regulator haptic driver");
264MODULE_LICENSE("GPL");
265
