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
30enum max77693_haptic_motor_type {
31	MAX77693_HAPTIC_ERM = 0,
32	MAX77693_HAPTIC_LRA,
33};
34
35enum max77693_haptic_pulse_mode {
36	MAX77693_HAPTIC_EXTERNAL_MODE = 0,
37	MAX77693_HAPTIC_INTERNAL_MODE,
38};
39
40enum 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
47struct 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
67static 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
84static 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
104static 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
139static 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
158static 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
184err_enable_config:
185	max77693_haptic_lowsys(haptic, false);
186err_enable_lowsys:
187	pwm_disable(haptic->pwm_dev);
188}
189
190static 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
210err_disable_lowsys:
211	max77693_haptic_configure(haptic, true);
212}
213
214static 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
232static 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
258static 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
277static 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
293static 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 = max77693->type;
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
378static int 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
391static int 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
404static DEFINE_SIMPLE_DEV_PM_OPS(max77693_haptic_pm_ops,
405				max77693_haptic_suspend,
406				max77693_haptic_resume);
407
408static const struct platform_device_id max77693_haptic_id[] = {
409	{ "max77693-haptic", },
410	{ "max77843-haptic", },
411	{},
412};
413MODULE_DEVICE_TABLE(platform, max77693_haptic_id);
414
415static const struct of_device_id of_max77693_haptic_dt_match[] = {
416	{ .compatible = "maxim,max77693-haptic", },
417	{ .compatible = "maxim,max77843-haptic", },
418	{ /* sentinel */ },
419};
420MODULE_DEVICE_TABLE(of, of_max77693_haptic_dt_match);
421
422static struct platform_driver max77693_haptic_driver = {
423	.driver		= {
424		.name	= "max77693-haptic",
425		.pm	= pm_sleep_ptr(&max77693_haptic_pm_ops),
426		.of_match_table = of_max77693_haptic_dt_match,
427	},
428	.probe		= max77693_haptic_probe,
429	.id_table	= max77693_haptic_id,
430};
431module_platform_driver(max77693_haptic_driver);
432
433MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
434MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
435MODULE_DESCRIPTION("MAXIM 77693/77843 Haptic driver");
436MODULE_LICENSE("GPL");
437