https://github.com/torvalds/linux
Tip revision: fb33c6510d5595144d585aa194d377cf74d31911 authored by Linus Torvalds on 15 March 2020, 22:01:23 UTC
Linux 5.6-rc6
Linux 5.6-rc6
Tip revision: fb33c65
pwm-vibra.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PWM vibrator driver
*
* Copyright (C) 2017 Collabora Ltd.
*
* Based on previous work from:
* Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
*
* Based on PWM beeper driver:
* Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
*/
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/pwm.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
struct pwm_vibrator {
struct input_dev *input;
struct pwm_device *pwm;
struct pwm_device *pwm_dir;
struct regulator *vcc;
struct work_struct play_work;
u16 level;
u32 direction_duty_cycle;
bool vcc_on;
};
static int pwm_vibrator_start(struct pwm_vibrator *vibrator)
{
struct device *pdev = vibrator->input->dev.parent;
struct pwm_state state;
int err;
if (!vibrator->vcc_on) {
err = regulator_enable(vibrator->vcc);
if (err) {
dev_err(pdev, "failed to enable regulator: %d", err);
return err;
}
vibrator->vcc_on = true;
}
pwm_get_state(vibrator->pwm, &state);
pwm_set_relative_duty_cycle(&state, vibrator->level, 0xffff);
state.enabled = true;
err = pwm_apply_state(vibrator->pwm, &state);
if (err) {
dev_err(pdev, "failed to apply pwm state: %d", err);
return err;
}
if (vibrator->pwm_dir) {
pwm_get_state(vibrator->pwm_dir, &state);
state.duty_cycle = vibrator->direction_duty_cycle;
state.enabled = true;
err = pwm_apply_state(vibrator->pwm_dir, &state);
if (err) {
dev_err(pdev, "failed to apply dir-pwm state: %d", err);
pwm_disable(vibrator->pwm);
return err;
}
}
return 0;
}
static void pwm_vibrator_stop(struct pwm_vibrator *vibrator)
{
if (vibrator->pwm_dir)
pwm_disable(vibrator->pwm_dir);
pwm_disable(vibrator->pwm);
if (vibrator->vcc_on) {
regulator_disable(vibrator->vcc);
vibrator->vcc_on = false;
}
}
static void pwm_vibrator_play_work(struct work_struct *work)
{
struct pwm_vibrator *vibrator = container_of(work,
struct pwm_vibrator, play_work);
if (vibrator->level)
pwm_vibrator_start(vibrator);
else
pwm_vibrator_stop(vibrator);
}
static int pwm_vibrator_play_effect(struct input_dev *dev, void *data,
struct ff_effect *effect)
{
struct pwm_vibrator *vibrator = input_get_drvdata(dev);
vibrator->level = effect->u.rumble.strong_magnitude;
if (!vibrator->level)
vibrator->level = effect->u.rumble.weak_magnitude;
schedule_work(&vibrator->play_work);
return 0;
}
static void pwm_vibrator_close(struct input_dev *input)
{
struct pwm_vibrator *vibrator = input_get_drvdata(input);
cancel_work_sync(&vibrator->play_work);
pwm_vibrator_stop(vibrator);
}
static int pwm_vibrator_probe(struct platform_device *pdev)
{
struct pwm_vibrator *vibrator;
struct pwm_state state;
int err;
vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
if (!vibrator)
return -ENOMEM;
vibrator->input = devm_input_allocate_device(&pdev->dev);
if (!vibrator->input)
return -ENOMEM;
vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
err = PTR_ERR_OR_ZERO(vibrator->vcc);
if (err) {
if (err != -EPROBE_DEFER)
dev_err(&pdev->dev, "Failed to request regulator: %d",
err);
return err;
}
vibrator->pwm = devm_pwm_get(&pdev->dev, "enable");
err = PTR_ERR_OR_ZERO(vibrator->pwm);
if (err) {
if (err != -EPROBE_DEFER)
dev_err(&pdev->dev, "Failed to request main pwm: %d",
err);
return err;
}
INIT_WORK(&vibrator->play_work, pwm_vibrator_play_work);
/* Sync up PWM state and ensure it is off. */
pwm_init_state(vibrator->pwm, &state);
state.enabled = false;
err = pwm_apply_state(vibrator->pwm, &state);
if (err) {
dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
err);
return err;
}
vibrator->pwm_dir = devm_pwm_get(&pdev->dev, "direction");
err = PTR_ERR_OR_ZERO(vibrator->pwm_dir);
switch (err) {
case 0:
/* Sync up PWM state and ensure it is off. */
pwm_init_state(vibrator->pwm_dir, &state);
state.enabled = false;
err = pwm_apply_state(vibrator->pwm_dir, &state);
if (err) {
dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
err);
return err;
}
vibrator->direction_duty_cycle =
pwm_get_period(vibrator->pwm_dir) / 2;
device_property_read_u32(&pdev->dev, "direction-duty-cycle-ns",
&vibrator->direction_duty_cycle);
break;
case -ENODATA:
/* Direction PWM is optional */
vibrator->pwm_dir = NULL;
break;
default:
dev_err(&pdev->dev, "Failed to request direction pwm: %d", err);
/* Fall through */
case -EPROBE_DEFER:
return err;
}
vibrator->input->name = "pwm-vibrator";
vibrator->input->id.bustype = BUS_HOST;
vibrator->input->dev.parent = &pdev->dev;
vibrator->input->close = pwm_vibrator_close;
input_set_drvdata(vibrator->input, vibrator);
input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
err = input_ff_create_memless(vibrator->input, NULL,
pwm_vibrator_play_effect);
if (err) {
dev_err(&pdev->dev, "Couldn't create FF dev: %d", err);
return err;
}
err = input_register_device(vibrator->input);
if (err) {
dev_err(&pdev->dev, "Couldn't register input dev: %d", err);
return err;
}
platform_set_drvdata(pdev, vibrator);
return 0;
}
static int __maybe_unused pwm_vibrator_suspend(struct device *dev)
{
struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
cancel_work_sync(&vibrator->play_work);
if (vibrator->level)
pwm_vibrator_stop(vibrator);
return 0;
}
static int __maybe_unused pwm_vibrator_resume(struct device *dev)
{
struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
if (vibrator->level)
pwm_vibrator_start(vibrator);
return 0;
}
static SIMPLE_DEV_PM_OPS(pwm_vibrator_pm_ops,
pwm_vibrator_suspend, pwm_vibrator_resume);
#ifdef CONFIG_OF
static const struct of_device_id pwm_vibra_dt_match_table[] = {
{ .compatible = "pwm-vibrator" },
{},
};
MODULE_DEVICE_TABLE(of, pwm_vibra_dt_match_table);
#endif
static struct platform_driver pwm_vibrator_driver = {
.probe = pwm_vibrator_probe,
.driver = {
.name = "pwm-vibrator",
.pm = &pwm_vibrator_pm_ops,
.of_match_table = of_match_ptr(pwm_vibra_dt_match_table),
},
};
module_platform_driver(pwm_vibrator_driver);
MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
MODULE_DESCRIPTION("PWM vibrator driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pwm-vibrator");