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
 27struct 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
 37static 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
 56static 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
 66static 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
 77static 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
 93static 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
102static 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
160static 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
172static 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
183static SIMPLE_DEV_PM_OPS(gpio_vibrator_pm_ops,
184			 gpio_vibrator_suspend, gpio_vibrator_resume);
185
186#ifdef CONFIG_OF
187static const struct of_device_id gpio_vibra_dt_match_table[] = {
188	{ .compatible = "gpio-vibrator" },
189	{}
190};
191MODULE_DEVICE_TABLE(of, gpio_vibra_dt_match_table);
192#endif
193
194static 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};
202module_platform_driver(gpio_vibrator_driver);
203
204MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xy>");
205MODULE_DESCRIPTION("GPIO vibrator driver");
206MODULE_LICENSE("GPL");
207MODULE_ALIAS("platform:gpio-vibrator");