1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * GPIO vibrator driver
4 *
5 * Copyright (C) 2019 Luca Weiss <luca@z3ntu.xyz>
6 *
7 * Based on PWM vibrator driver:
8 * Copyright (C) 2017 Collabora Ltd.
9 *
10 * Based on previous work from:
11 * Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
12 *
13 * Based on PWM beeper driver:
14 * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
15 */
16
17 #include <linux/gpio/consumer.h>
18 #include <linux/input.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/of_device.h>
22 #include <linux/platform_device.h>
23 #include <linux/property.h>
24 #include <linux/regulator/consumer.h>
25 #include <linux/slab.h>
26
27 struct gpio_vibrator {
28 struct input_dev *input;
29 struct gpio_desc *gpio;
30 struct regulator *vcc;
31
32 struct work_struct play_work;
33 bool running;
34 bool vcc_on;
35 };
36
gpio_vibrator_start(struct gpio_vibrator * vibrator)37 static int gpio_vibrator_start(struct gpio_vibrator *vibrator)
38 {
39 struct device *pdev = vibrator->input->dev.parent;
40 int err;
41
42 if (!vibrator->vcc_on) {
43 err = regulator_enable(vibrator->vcc);
44 if (err) {
45 dev_err(pdev, "failed to enable regulator: %d\n", err);
46 return err;
47 }
48 vibrator->vcc_on = true;
49 }
50
51 gpiod_set_value_cansleep(vibrator->gpio, 1);
52
53 return 0;
54 }
55
gpio_vibrator_stop(struct gpio_vibrator * vibrator)56 static void gpio_vibrator_stop(struct gpio_vibrator *vibrator)
57 {
58 gpiod_set_value_cansleep(vibrator->gpio, 0);
59
60 if (vibrator->vcc_on) {
61 regulator_disable(vibrator->vcc);
62 vibrator->vcc_on = false;
63 }
64 }
65
gpio_vibrator_play_work(struct work_struct * work)66 static void gpio_vibrator_play_work(struct work_struct *work)
67 {
68 struct gpio_vibrator *vibrator =
69 container_of(work, struct gpio_vibrator, play_work);
70
71 if (vibrator->running)
72 gpio_vibrator_start(vibrator);
73 else
74 gpio_vibrator_stop(vibrator);
75 }
76
gpio_vibrator_play_effect(struct input_dev * dev,void * data,struct ff_effect * effect)77 static int gpio_vibrator_play_effect(struct input_dev *dev, void *data,
78 struct ff_effect *effect)
79 {
80 struct gpio_vibrator *vibrator = input_get_drvdata(dev);
81 int level;
82
83 level = effect->u.rumble.strong_magnitude;
84 if (!level)
85 level = effect->u.rumble.weak_magnitude;
86
87 vibrator->running = level;
88 schedule_work(&vibrator->play_work);
89
90 return 0;
91 }
92
gpio_vibrator_close(struct input_dev * input)93 static void gpio_vibrator_close(struct input_dev *input)
94 {
95 struct gpio_vibrator *vibrator = input_get_drvdata(input);
96
97 cancel_work_sync(&vibrator->play_work);
98 gpio_vibrator_stop(vibrator);
99 vibrator->running = false;
100 }
101
gpio_vibrator_probe(struct platform_device * pdev)102 static int gpio_vibrator_probe(struct platform_device *pdev)
103 {
104 struct gpio_vibrator *vibrator;
105 int err;
106
107 vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
108 if (!vibrator)
109 return -ENOMEM;
110
111 vibrator->input = devm_input_allocate_device(&pdev->dev);
112 if (!vibrator->input)
113 return -ENOMEM;
114
115 vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
116 err = PTR_ERR_OR_ZERO(vibrator->vcc);
117 if (err) {
118 if (err != -EPROBE_DEFER)
119 dev_err(&pdev->dev, "Failed to request regulator: %d\n",
120 err);
121 return err;
122 }
123
124 vibrator->gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
125 err = PTR_ERR_OR_ZERO(vibrator->gpio);
126 if (err) {
127 if (err != -EPROBE_DEFER)
128 dev_err(&pdev->dev, "Failed to request main gpio: %d\n",
129 err);
130 return err;
131 }
132
133 INIT_WORK(&vibrator->play_work, gpio_vibrator_play_work);
134
135 vibrator->input->name = "gpio-vibrator";
136 vibrator->input->id.bustype = BUS_HOST;
137 vibrator->input->close = gpio_vibrator_close;
138
139 input_set_drvdata(vibrator->input, vibrator);
140 input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
141
142 err = input_ff_create_memless(vibrator->input, NULL,
143 gpio_vibrator_play_effect);
144 if (err) {
145 dev_err(&pdev->dev, "Couldn't create FF dev: %d\n", err);
146 return err;
147 }
148
149 err = input_register_device(vibrator->input);
150 if (err) {
151 dev_err(&pdev->dev, "Couldn't register input dev: %d\n", err);
152 return err;
153 }
154
155 platform_set_drvdata(pdev, vibrator);
156
157 return 0;
158 }
159
gpio_vibrator_suspend(struct device * dev)160 static int __maybe_unused gpio_vibrator_suspend(struct device *dev)
161 {
162 struct platform_device *pdev = to_platform_device(dev);
163 struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
164
165 cancel_work_sync(&vibrator->play_work);
166 if (vibrator->running)
167 gpio_vibrator_stop(vibrator);
168
169 return 0;
170 }
171
gpio_vibrator_resume(struct device * dev)172 static int __maybe_unused gpio_vibrator_resume(struct device *dev)
173 {
174 struct platform_device *pdev = to_platform_device(dev);
175 struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
176
177 if (vibrator->running)
178 gpio_vibrator_start(vibrator);
179
180 return 0;
181 }
182
183 static SIMPLE_DEV_PM_OPS(gpio_vibrator_pm_ops,
184 gpio_vibrator_suspend, gpio_vibrator_resume);
185
186 #ifdef CONFIG_OF
187 static const struct of_device_id gpio_vibra_dt_match_table[] = {
188 { .compatible = "gpio-vibrator" },
189 {}
190 };
191 MODULE_DEVICE_TABLE(of, gpio_vibra_dt_match_table);
192 #endif
193
194 static struct platform_driver gpio_vibrator_driver = {
195 .probe = gpio_vibrator_probe,
196 .driver = {
197 .name = "gpio-vibrator",
198 .pm = &gpio_vibrator_pm_ops,
199 .of_match_table = of_match_ptr(gpio_vibra_dt_match_table),
200 },
201 };
202 module_platform_driver(gpio_vibrator_driver);
203
204 MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xy>");
205 MODULE_DESCRIPTION("GPIO vibrator driver");
206 MODULE_LICENSE("GPL");
207 MODULE_ALIAS("platform:gpio-vibrator");
208
