linux/drivers/input/misc/gpio-vibra.c
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   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");
 208