1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * MAXIM MAX77693/MAX77843 Haptic device driver
4  *
5  * Copyright (C) 2014,2015 Samsung Electronics
6  * Jaewon Kim <jaewon02.kim@samsung.com>
7  * Krzysztof Kozlowski <krzk@kernel.org>
8  *
9  * This program is not provided / owned by Maxim Integrated Products.
10  */
11 
12 #include <linux/err.h>
13 #include <linux/init.h>
14 #include <linux/i2c.h>
15 #include <linux/regmap.h>
16 #include <linux/input.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/pwm.h>
20 #include <linux/slab.h>
21 #include <linux/workqueue.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/mfd/max77693.h>
24 #include <linux/mfd/max77693-common.h>
25 #include <linux/mfd/max77693-private.h>
26 #include <linux/mfd/max77843-private.h>
27 
28 #define MAX_MAGNITUDE_SHIFT	16
29 
30 enum max77693_haptic_motor_type {
31 	MAX77693_HAPTIC_ERM = 0,
32 	MAX77693_HAPTIC_LRA,
33 };
34 
35 enum max77693_haptic_pulse_mode {
36 	MAX77693_HAPTIC_EXTERNAL_MODE = 0,
37 	MAX77693_HAPTIC_INTERNAL_MODE,
38 };
39 
40 enum max77693_haptic_pwm_divisor {
41 	MAX77693_HAPTIC_PWM_DIVISOR_32 = 0,
42 	MAX77693_HAPTIC_PWM_DIVISOR_64,
43 	MAX77693_HAPTIC_PWM_DIVISOR_128,
44 	MAX77693_HAPTIC_PWM_DIVISOR_256,
45 };
46 
47 struct max77693_haptic {
48 	enum max77693_types dev_type;
49 
50 	struct regmap *regmap_pmic;
51 	struct regmap *regmap_haptic;
52 	struct device *dev;
53 	struct input_dev *input_dev;
54 	struct pwm_device *pwm_dev;
55 	struct regulator *motor_reg;
56 
57 	bool enabled;
58 	bool suspend_state;
59 	unsigned int magnitude;
60 	unsigned int pwm_duty;
61 	enum max77693_haptic_motor_type type;
62 	enum max77693_haptic_pulse_mode mode;
63 
64 	struct work_struct work;
65 };
66 
67 static int max77693_haptic_set_duty_cycle(struct max77693_haptic *haptic)
68 {
69 	struct pwm_args pargs;
70 	int delta;
71 	int error;
72 
73 	pwm_get_args(haptic->pwm_dev, &pargs);
74 	delta = (pargs.period + haptic->pwm_duty) / 2;
75 	error = pwm_config(haptic->pwm_dev, delta, pargs.period);
76 	if (error) {
77 		dev_err(haptic->dev, "failed to configure pwm: %d\n", error);
78 		return error;
79 	}
80 
81 	return 0;
82 }
83 
84 static int max77843_haptic_bias(struct max77693_haptic *haptic, bool on)
85 {
86 	int error;
87 
88 	if (haptic->dev_type != TYPE_MAX77843)
89 		return 0;
90 
91 	error = regmap_update_bits(haptic->regmap_haptic,
92 				   MAX77843_SYS_REG_MAINCTRL1,
93 				   MAX77843_MAINCTRL1_BIASEN_MASK,
94 				   on << MAINCTRL1_BIASEN_SHIFT);
95 	if (error) {
96 		dev_err(haptic->dev, "failed to %s bias: %d\n",
97 			on ? "enable" : "disable", error);
98 		return error;
99 	}
100 
101 	return 0;
102 }
103 
104 static int max77693_haptic_configure(struct max77693_haptic *haptic,
105 				     bool enable)
106 {
107 	unsigned int value, config_reg;
108 	int error;
109 
110 	switch (haptic->dev_type) {
111 	case TYPE_MAX77693:
112 		value = ((haptic->type << MAX77693_CONFIG2_MODE) |
113 			(enable << MAX77693_CONFIG2_MEN) |
114 			(haptic->mode << MAX77693_CONFIG2_HTYP) |
115 			MAX77693_HAPTIC_PWM_DIVISOR_128);
116 		config_reg = MAX77693_HAPTIC_REG_CONFIG2;
117 		break;
118 	case TYPE_MAX77843:
119 		value = (haptic->type << MCONFIG_MODE_SHIFT) |
120 			(enable << MCONFIG_MEN_SHIFT) |
121 			MAX77693_HAPTIC_PWM_DIVISOR_128;
122 		config_reg = MAX77843_HAP_REG_MCONFIG;
123 		break;
124 	default:
125 		return -EINVAL;
126 	}
127 
128 	error = regmap_write(haptic->regmap_haptic,
129 			     config_reg, value);
130 	if (error) {
131 		dev_err(haptic->dev,
132 			"failed to update haptic config: %d\n", error);
133 		return error;
134 	}
135 
136 	return 0;
137 }
138 
139 static int max77693_haptic_lowsys(struct max77693_haptic *haptic, bool enable)
140 {
141 	int error;
142 
143 	if (haptic->dev_type != TYPE_MAX77693)
144 		return 0;
145 
146 	error = regmap_update_bits(haptic->regmap_pmic,
147 				   MAX77693_PMIC_REG_LSCNFG,
148 				   MAX77693_PMIC_LOW_SYS_MASK,
149 				   enable << MAX77693_PMIC_LOW_SYS_SHIFT);
150 	if (error) {
151 		dev_err(haptic->dev, "cannot update pmic regmap: %d\n", error);
152 		return error;
153 	}
154 
155 	return 0;
156 }
157 
158 static void max77693_haptic_enable(struct max77693_haptic *haptic)
159 {
160 	int error;
161 
162 	if (haptic->enabled)
163 		return;
164 
165 	error = pwm_enable(haptic->pwm_dev);
166 	if (error) {
167 		dev_err(haptic->dev,
168 			"failed to enable haptic pwm device: %d\n", error);
169 		return;
170 	}
171 
172 	error = max77693_haptic_lowsys(haptic, true);
173 	if (error)
174 		goto err_enable_lowsys;
175 
176 	error = max77693_haptic_configure(haptic, true);
177 	if (error)
178 		goto err_enable_config;
179 
180 	haptic->enabled = true;
181 
182 	return;
183 
184 err_enable_config:
185 	max77693_haptic_lowsys(haptic, false);
186 err_enable_lowsys:
187 	pwm_disable(haptic->pwm_dev);
188 }
189 
190 static void max77693_haptic_disable(struct max77693_haptic *haptic)
191 {
192 	int error;
193 
194 	if (!haptic->enabled)
195 		return;
196 
197 	error = max77693_haptic_configure(haptic, false);
198 	if (error)
199 		return;
200 
201 	error = max77693_haptic_lowsys(haptic, false);
202 	if (error)
203 		goto err_disable_lowsys;
204 
205 	pwm_disable(haptic->pwm_dev);
206 	haptic->enabled = false;
207 
208 	return;
209 
210 err_disable_lowsys:
211 	max77693_haptic_configure(haptic, true);
212 }
213 
214 static void max77693_haptic_play_work(struct work_struct *work)
215 {
216 	struct max77693_haptic *haptic =
217 			container_of(work, struct max77693_haptic, work);
218 	int error;
219 
220 	error = max77693_haptic_set_duty_cycle(haptic);
221 	if (error) {
222 		dev_err(haptic->dev, "failed to set duty cycle: %d\n", error);
223 		return;
224 	}
225 
226 	if (haptic->magnitude)
227 		max77693_haptic_enable(haptic);
228 	else
229 		max77693_haptic_disable(haptic);
230 }
231 
232 static int max77693_haptic_play_effect(struct input_dev *dev, void *data,
233 				       struct ff_effect *effect)
234 {
235 	struct max77693_haptic *haptic = input_get_drvdata(dev);
236 	struct pwm_args pargs;
237 	u64 period_mag_multi;
238 
239 	haptic->magnitude = effect->u.rumble.strong_magnitude;
240 	if (!haptic->magnitude)
241 		haptic->magnitude = effect->u.rumble.weak_magnitude;
242 
243 	/*
244 	 * The magnitude comes from force-feedback interface.
245 	 * The formula to convert magnitude to pwm_duty as follows:
246 	 * - pwm_duty = (magnitude * pwm_period) / MAX_MAGNITUDE(0xFFFF)
247 	 */
248 	pwm_get_args(haptic->pwm_dev, &pargs);
249 	period_mag_multi = (u64)pargs.period * haptic->magnitude;
250 	haptic->pwm_duty = (unsigned int)(period_mag_multi >>
251 						MAX_MAGNITUDE_SHIFT);
252 
253 	schedule_work(&haptic->work);
254 
255 	return 0;
256 }
257 
258 static int max77693_haptic_open(struct input_dev *dev)
259 {
260 	struct max77693_haptic *haptic = input_get_drvdata(dev);
261 	int error;
262 
263 	error = max77843_haptic_bias(haptic, true);
264 	if (error)
265 		return error;
266 
267 	error = regulator_enable(haptic->motor_reg);
268 	if (error) {
269 		dev_err(haptic->dev,
270 			"failed to enable regulator: %d\n", error);
271 		return error;
272 	}
273 
274 	return 0;
275 }
276 
277 static void max77693_haptic_close(struct input_dev *dev)
278 {
279 	struct max77693_haptic *haptic = input_get_drvdata(dev);
280 	int error;
281 
282 	cancel_work_sync(&haptic->work);
283 	max77693_haptic_disable(haptic);
284 
285 	error = regulator_disable(haptic->motor_reg);
286 	if (error)
287 		dev_err(haptic->dev,
288 			"failed to disable regulator: %d\n", error);
289 
290 	max77843_haptic_bias(haptic, false);
291 }
292 
293 static int max77693_haptic_probe(struct platform_device *pdev)
294 {
295 	struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
296 	struct max77693_haptic *haptic;
297 	int error;
298 
299 	haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
300 	if (!haptic)
301 		return -ENOMEM;
302 
303 	haptic->regmap_pmic = max77693->regmap;
304 	haptic->dev = &pdev->dev;
305 	haptic->type = MAX77693_HAPTIC_LRA;
306 	haptic->mode = MAX77693_HAPTIC_EXTERNAL_MODE;
307 	haptic->suspend_state = false;
308 
309 	/* Variant-specific init */
310 	haptic->dev_type = platform_get_device_id(pdev)->driver_data;
311 	switch (haptic->dev_type) {
312 	case TYPE_MAX77693:
313 		haptic->regmap_haptic = max77693->regmap_haptic;
314 		break;
315 	case TYPE_MAX77843:
316 		haptic->regmap_haptic = max77693->regmap;
317 		break;
318 	default:
319 		dev_err(&pdev->dev, "unsupported device type: %u\n",
320 			haptic->dev_type);
321 		return -EINVAL;
322 	}
323 
324 	INIT_WORK(&haptic->work, max77693_haptic_play_work);
325 
326 	/* Get pwm and regulatot for haptic device */
327 	haptic->pwm_dev = devm_pwm_get(&pdev->dev, NULL);
328 	if (IS_ERR(haptic->pwm_dev)) {
329 		dev_err(&pdev->dev, "failed to get pwm device\n");
330 		return PTR_ERR(haptic->pwm_dev);
331 	}
332 
333 	/*
334 	 * FIXME: pwm_apply_args() should be removed when switching to the
335 	 * atomic PWM API.
336 	 */
337 	pwm_apply_args(haptic->pwm_dev);
338 
339 	haptic->motor_reg = devm_regulator_get(&pdev->dev, "haptic");
340 	if (IS_ERR(haptic->motor_reg)) {
341 		dev_err(&pdev->dev, "failed to get regulator\n");
342 		return PTR_ERR(haptic->motor_reg);
343 	}
344 
345 	/* Initialize input device for haptic device */
346 	haptic->input_dev = devm_input_allocate_device(&pdev->dev);
347 	if (!haptic->input_dev) {
348 		dev_err(&pdev->dev, "failed to allocate input device\n");
349 		return -ENOMEM;
350 	}
351 
352 	haptic->input_dev->name = "max77693-haptic";
353 	haptic->input_dev->id.version = 1;
354 	haptic->input_dev->dev.parent = &pdev->dev;
355 	haptic->input_dev->open = max77693_haptic_open;
356 	haptic->input_dev->close = max77693_haptic_close;
357 	input_set_drvdata(haptic->input_dev, haptic);
358 	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
359 
360 	error = input_ff_create_memless(haptic->input_dev, NULL,
361 				max77693_haptic_play_effect);
362 	if (error) {
363 		dev_err(&pdev->dev, "failed to create force-feedback\n");
364 		return error;
365 	}
366 
367 	error = input_register_device(haptic->input_dev);
368 	if (error) {
369 		dev_err(&pdev->dev, "failed to register input device\n");
370 		return error;
371 	}
372 
373 	platform_set_drvdata(pdev, haptic);
374 
375 	return 0;
376 }
377 
378 static int __maybe_unused max77693_haptic_suspend(struct device *dev)
379 {
380 	struct platform_device *pdev = to_platform_device(dev);
381 	struct max77693_haptic *haptic = platform_get_drvdata(pdev);
382 
383 	if (haptic->enabled) {
384 		max77693_haptic_disable(haptic);
385 		haptic->suspend_state = true;
386 	}
387 
388 	return 0;
389 }
390 
391 static int __maybe_unused max77693_haptic_resume(struct device *dev)
392 {
393 	struct platform_device *pdev = to_platform_device(dev);
394 	struct max77693_haptic *haptic = platform_get_drvdata(pdev);
395 
396 	if (haptic->suspend_state) {
397 		max77693_haptic_enable(haptic);
398 		haptic->suspend_state = false;
399 	}
400 
401 	return 0;
402 }
403 
404 static SIMPLE_DEV_PM_OPS(max77693_haptic_pm_ops,
405 			 max77693_haptic_suspend, max77693_haptic_resume);
406 
407 static const struct platform_device_id max77693_haptic_id[] = {
408 	{ "max77693-haptic", TYPE_MAX77693 },
409 	{ "max77843-haptic", TYPE_MAX77843 },
410 	{},
411 };
412 MODULE_DEVICE_TABLE(platform, max77693_haptic_id);
413 
414 static struct platform_driver max77693_haptic_driver = {
415 	.driver		= {
416 		.name	= "max77693-haptic",
417 		.pm	= &max77693_haptic_pm_ops,
418 	},
419 	.probe		= max77693_haptic_probe,
420 	.id_table	= max77693_haptic_id,
421 };
422 module_platform_driver(max77693_haptic_driver);
423 
424 MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
425 MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
426 MODULE_DESCRIPTION("MAXIM 77693/77843 Haptic driver");
427 MODULE_ALIAS("platform:max77693-haptic");
428 MODULE_LICENSE("GPL");
429