1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  PWM vibrator driver
  4 *
  5 *  Copyright (C) 2017 Collabora Ltd.
  6 *
  7 *  Based on previous work from:
  8 *  Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
  9 *
 10 *  Based on PWM beeper driver:
 11 *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
 12 */
 13
 14#include <linux/gpio/consumer.h>
 15#include <linux/input.h>
 16#include <linux/kernel.h>
 17#include <linux/module.h>
 18#include <linux/of.h>
 19#include <linux/platform_device.h>
 20#include <linux/property.h>
 21#include <linux/pwm.h>
 22#include <linux/regulator/consumer.h>
 23#include <linux/slab.h>
 24
 25struct pwm_vibrator {
 26	struct input_dev *input;
 27	struct gpio_desc *enable_gpio;
 28	struct pwm_device *pwm;
 29	struct pwm_device *pwm_dir;
 30	struct regulator *vcc;
 31
 32	struct work_struct play_work;
 33	u16 level;
 34	u32 direction_duty_cycle;
 35	bool vcc_on;
 36};
 37
 38static int pwm_vibrator_start(struct pwm_vibrator *vibrator)
 39{
 40	struct device *pdev = vibrator->input->dev.parent;
 41	struct pwm_state state;
 42	int err;
 43
 44	if (!vibrator->vcc_on) {
 45		err = regulator_enable(vibrator->vcc);
 46		if (err) {
 47			dev_err(pdev, "failed to enable regulator: %d\n", err);
 48			return err;
 49		}
 50		vibrator->vcc_on = true;
 51	}
 52
 53	gpiod_set_value_cansleep(vibrator->enable_gpio, 1);
 54
 55	pwm_get_state(vibrator->pwm, &state);
 56	pwm_set_relative_duty_cycle(&state, vibrator->level, 0xffff);
 57	state.enabled = true;
 58
 59	err = pwm_apply_might_sleep(vibrator->pwm, &state);
 60	if (err) {
 61		dev_err(pdev, "failed to apply pwm state: %d\n", err);
 62		return err;
 63	}
 64
 65	if (vibrator->pwm_dir) {
 66		pwm_get_state(vibrator->pwm_dir, &state);
 67		state.duty_cycle = vibrator->direction_duty_cycle;
 68		state.enabled = true;
 69
 70		err = pwm_apply_might_sleep(vibrator->pwm_dir, &state);
 71		if (err) {
 72			dev_err(pdev, "failed to apply dir-pwm state: %d\n", err);
 73			pwm_disable(vibrator->pwm);
 74			return err;
 75		}
 76	}
 77
 78	return 0;
 79}
 80
 81static void pwm_vibrator_stop(struct pwm_vibrator *vibrator)
 82{
 83	if (vibrator->pwm_dir)
 84		pwm_disable(vibrator->pwm_dir);
 85	pwm_disable(vibrator->pwm);
 86
 87	gpiod_set_value_cansleep(vibrator->enable_gpio, 0);
 88
 89	if (vibrator->vcc_on) {
 90		regulator_disable(vibrator->vcc);
 91		vibrator->vcc_on = false;
 92	}
 93}
 94
 95static void pwm_vibrator_play_work(struct work_struct *work)
 96{
 97	struct pwm_vibrator *vibrator = container_of(work,
 98					struct pwm_vibrator, play_work);
 99
100	if (vibrator->level)
101		pwm_vibrator_start(vibrator);
102	else
103		pwm_vibrator_stop(vibrator);
104}
105
106static int pwm_vibrator_play_effect(struct input_dev *dev, void *data,
107				    struct ff_effect *effect)
108{
109	struct pwm_vibrator *vibrator = input_get_drvdata(dev);
110
111	vibrator->level = effect->u.rumble.strong_magnitude;
112	if (!vibrator->level)
113		vibrator->level = effect->u.rumble.weak_magnitude;
114
115	schedule_work(&vibrator->play_work);
116
117	return 0;
118}
119
120static void pwm_vibrator_close(struct input_dev *input)
121{
122	struct pwm_vibrator *vibrator = input_get_drvdata(input);
123
124	cancel_work_sync(&vibrator->play_work);
125	pwm_vibrator_stop(vibrator);
126}
127
128static int pwm_vibrator_probe(struct platform_device *pdev)
129{
130	struct pwm_vibrator *vibrator;
131	struct pwm_state state;
132	int err;
133
134	vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
135	if (!vibrator)
136		return -ENOMEM;
137
138	vibrator->input = devm_input_allocate_device(&pdev->dev);
139	if (!vibrator->input)
140		return -ENOMEM;
141
142	vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
143	if (IS_ERR(vibrator->vcc))
144		return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->vcc),
145				     "Failed to request regulator\n");
146
147	vibrator->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
148							GPIOD_OUT_LOW);
149	if (IS_ERR(vibrator->enable_gpio))
150		return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->enable_gpio),
151				     "Failed to request enable gpio\n");
152
153	vibrator->pwm = devm_pwm_get(&pdev->dev, "enable");
154	if (IS_ERR(vibrator->pwm))
155		return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->pwm),
156				     "Failed to request main pwm\n");
157
158	INIT_WORK(&vibrator->play_work, pwm_vibrator_play_work);
159
160	/* Sync up PWM state and ensure it is off. */
161	pwm_init_state(vibrator->pwm, &state);
162	state.enabled = false;
163	err = pwm_apply_might_sleep(vibrator->pwm, &state);
164	if (err) {
165		dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
166			err);
167		return err;
168	}
169
170	vibrator->pwm_dir = devm_pwm_get(&pdev->dev, "direction");
171	err = PTR_ERR_OR_ZERO(vibrator->pwm_dir);
172	switch (err) {
173	case 0:
174		/* Sync up PWM state and ensure it is off. */
175		pwm_init_state(vibrator->pwm_dir, &state);
176		state.enabled = false;
177		err = pwm_apply_might_sleep(vibrator->pwm_dir, &state);
178		if (err) {
179			dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
180				err);
181			return err;
182		}
183
184		vibrator->direction_duty_cycle =
185			pwm_get_period(vibrator->pwm_dir) / 2;
186		device_property_read_u32(&pdev->dev, "direction-duty-cycle-ns",
187					 &vibrator->direction_duty_cycle);
188		break;
189
190	case -ENODATA:
191		/* Direction PWM is optional */
192		vibrator->pwm_dir = NULL;
193		break;
194
195	default:
196		dev_err(&pdev->dev, "Failed to request direction pwm: %d\n", err);
197		fallthrough;
198
199	case -EPROBE_DEFER:
200		return err;
201	}
202
203	vibrator->input->name = "pwm-vibrator";
204	vibrator->input->id.bustype = BUS_HOST;
205	vibrator->input->dev.parent = &pdev->dev;
206	vibrator->input->close = pwm_vibrator_close;
207
208	input_set_drvdata(vibrator->input, vibrator);
209	input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
210
211	err = input_ff_create_memless(vibrator->input, NULL,
212				      pwm_vibrator_play_effect);
213	if (err) {
214		dev_err(&pdev->dev, "Couldn't create FF dev: %d\n", err);
215		return err;
216	}
217
218	err = input_register_device(vibrator->input);
219	if (err) {
220		dev_err(&pdev->dev, "Couldn't register input dev: %d\n", err);
221		return err;
222	}
223
224	platform_set_drvdata(pdev, vibrator);
225
226	return 0;
227}
228
229static int pwm_vibrator_suspend(struct device *dev)
230{
231	struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
232
233	cancel_work_sync(&vibrator->play_work);
234	if (vibrator->level)
235		pwm_vibrator_stop(vibrator);
236
237	return 0;
238}
239
240static int pwm_vibrator_resume(struct device *dev)
241{
242	struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
243
244	if (vibrator->level)
245		pwm_vibrator_start(vibrator);
246
247	return 0;
248}
249
250static DEFINE_SIMPLE_DEV_PM_OPS(pwm_vibrator_pm_ops,
251				pwm_vibrator_suspend, pwm_vibrator_resume);
252
253#ifdef CONFIG_OF
254static const struct of_device_id pwm_vibra_dt_match_table[] = {
255	{ .compatible = "pwm-vibrator" },
256	{},
257};
258MODULE_DEVICE_TABLE(of, pwm_vibra_dt_match_table);
259#endif
260
261static struct platform_driver pwm_vibrator_driver = {
262	.probe	= pwm_vibrator_probe,
263	.driver	= {
264		.name	= "pwm-vibrator",
265		.pm	= pm_sleep_ptr(&pwm_vibrator_pm_ops),
266		.of_match_table = of_match_ptr(pwm_vibra_dt_match_table),
267	},
268};
269module_platform_driver(pwm_vibrator_driver);
270
271MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
272MODULE_DESCRIPTION("PWM vibrator driver");
273MODULE_LICENSE("GPL");
274MODULE_ALIAS("platform:pwm-vibrator");