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