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 25 struct 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 38 static 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_state(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_state(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 81 static 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 95 static 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 } 105 106 static 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 } 119 120 static 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 } 127 128 static 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_state(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_state(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 } 228 229 static 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 } 239 240 static 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 } 249 250 static DEFINE_SIMPLE_DEV_PM_OPS(pwm_vibrator_pm_ops, 251 pwm_vibrator_suspend, pwm_vibrator_resume); 252 253 #ifdef CONFIG_OF 254 static const struct of_device_id pwm_vibra_dt_match_table[] = { 255 { .compatible = "pwm-vibrator" }, 256 {}, 257 }; 258 MODULE_DEVICE_TABLE(of, pwm_vibra_dt_match_table); 259 #endif 260 261 static 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 }; 269 module_platform_driver(pwm_vibrator_driver); 270 271 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>"); 272 MODULE_DESCRIPTION("PWM vibrator driver"); 273 MODULE_LICENSE("GPL"); 274 MODULE_ALIAS("platform:pwm-vibrator"); 275