drivers/input/misc/gpio-vibra.c

   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.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
  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
  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
  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
  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
  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
 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         if (IS_ERR(vibrator->vcc))
 117                 return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->vcc),
 118                                      "Failed to request regulator\n");
 119
 120         vibrator->gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
 121         if (IS_ERR(vibrator->gpio))
 122                 return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->gpio),
 123                                      "Failed to request main gpio\n");
 124
 125         INIT_WORK(&vibrator->play_work, gpio_vibrator_play_work);
 126
 127         vibrator->input->name = "gpio-vibrator";
 128         vibrator->input->id.bustype = BUS_HOST;
 129         vibrator->input->close = gpio_vibrator_close;
 130
 131         input_set_drvdata(vibrator->input, vibrator);
 132         input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
 133
 134         err = input_ff_create_memless(vibrator->input, NULL,
 135                                       gpio_vibrator_play_effect);
 136         if (err) {
 137                 dev_err(&pdev->dev, "Couldn't create FF dev: %d\n", err);
 138                 return err;
 139         }
 140
 141         err = input_register_device(vibrator->input);
 142         if (err) {
 143                 dev_err(&pdev->dev, "Couldn't register input dev: %d\n", err);
 144                 return err;
 145         }
 146
 147         platform_set_drvdata(pdev, vibrator);
 148
 149         return 0;
 150 }
 151
 152 static int gpio_vibrator_suspend(struct device *dev)
 153 {
 154         struct platform_device *pdev = to_platform_device(dev);
 155         struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
 156
 157         cancel_work_sync(&vibrator->play_work);
 158         if (vibrator->running)
 159                 gpio_vibrator_stop(vibrator);
 160
 161         return 0;
 162 }
 163
 164 static int gpio_vibrator_resume(struct device *dev)
 165 {
 166         struct platform_device *pdev = to_platform_device(dev);
 167         struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
 168
 169         if (vibrator->running)
 170                 gpio_vibrator_start(vibrator);
 171
 172         return 0;
 173 }
 174
 175 static DEFINE_SIMPLE_DEV_PM_OPS(gpio_vibrator_pm_ops,
 176                                 gpio_vibrator_suspend, gpio_vibrator_resume);
 177
 178 #ifdef CONFIG_OF
 179 static const struct of_device_id gpio_vibra_dt_match_table[] = {
 180         { .compatible = "gpio-vibrator" },
 181         {}
 182 };
 183 MODULE_DEVICE_TABLE(of, gpio_vibra_dt_match_table);
 184 #endif
 185
 186 static struct platform_driver gpio_vibrator_driver = {
 187         .probe  = gpio_vibrator_probe,
 188         .driver = {
 189                 .name   = "gpio-vibrator",
 190                 .pm     = pm_sleep_ptr(&gpio_vibrator_pm_ops),
 191                 .of_match_table = of_match_ptr(gpio_vibra_dt_match_table),
 192         },
 193 };
 194 module_platform_driver(gpio_vibrator_driver);
 195
 196 MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xy>");
 197 MODULE_DESCRIPTION("GPIO vibrator driver");
 198 MODULE_LICENSE("GPL");
 199 MODULE_ALIAS("platform:gpio-vibrator");