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"); 200