1/*
2 * DRV2667 haptics driver family
3 *
4 * Author: Dan Murphy <dmurphy@ti.com>
5 *
6 * Copyright: (C) 2014 Texas Instruments, Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 */
17
18#include <linux/i2c.h>
19#include <linux/input.h>
20#include <linux/module.h>
21#include <linux/platform_device.h>
22#include <linux/regmap.h>
23#include <linux/slab.h>
24#include <linux/delay.h>
25#include <linux/regulator/consumer.h>
26
27/* Contol registers */
28#define DRV2667_STATUS	0x00
29#define DRV2667_CTRL_1	0x01
30#define DRV2667_CTRL_2	0x02
31/* Waveform sequencer */
32#define DRV2667_WV_SEQ_0	0x03
33#define DRV2667_WV_SEQ_1	0x04
34#define DRV2667_WV_SEQ_2	0x05
35#define DRV2667_WV_SEQ_3	0x06
36#define DRV2667_WV_SEQ_4	0x07
37#define DRV2667_WV_SEQ_5	0x08
38#define DRV2667_WV_SEQ_6	0x09
39#define DRV2667_WV_SEQ_7	0x0A
40#define DRV2667_FIFO		0x0B
41#define DRV2667_PAGE		0xFF
42#define DRV2667_MAX_REG		DRV2667_PAGE
43
44#define DRV2667_PAGE_0		0x00
45#define DRV2667_PAGE_1		0x01
46#define DRV2667_PAGE_2		0x02
47#define DRV2667_PAGE_3		0x03
48#define DRV2667_PAGE_4		0x04
49#define DRV2667_PAGE_5		0x05
50#define DRV2667_PAGE_6		0x06
51#define DRV2667_PAGE_7		0x07
52#define DRV2667_PAGE_8		0x08
53
54/* RAM fields */
55#define DRV2667_RAM_HDR_SZ	0x0
56/* RAM Header addresses */
57#define DRV2667_RAM_START_HI	0x01
58#define DRV2667_RAM_START_LO	0x02
59#define DRV2667_RAM_STOP_HI		0x03
60#define DRV2667_RAM_STOP_LO		0x04
61#define DRV2667_RAM_REPEAT_CT	0x05
62/* RAM data addresses */
63#define DRV2667_RAM_AMP		0x06
64#define DRV2667_RAM_FREQ	0x07
65#define DRV2667_RAM_DURATION	0x08
66#define DRV2667_RAM_ENVELOPE	0x09
67
68/* Control 1 Register */
69#define DRV2667_25_VPP_GAIN		0x00
70#define DRV2667_50_VPP_GAIN		0x01
71#define DRV2667_75_VPP_GAIN		0x02
72#define DRV2667_100_VPP_GAIN	0x03
73#define DRV2667_DIGITAL_IN		0xfc
74#define DRV2667_ANALOG_IN		(1 << 2)
75
76/* Control 2 Register */
77#define DRV2667_GO			(1 << 0)
78#define DRV2667_STANDBY		(1 << 6)
79#define DRV2667_DEV_RST		(1 << 7)
80
81/* RAM Envelope settings */
82#define DRV2667_NO_ENV			0x00
83#define DRV2667_32_MS_ENV		0x01
84#define DRV2667_64_MS_ENV		0x02
85#define DRV2667_96_MS_ENV		0x03
86#define DRV2667_128_MS_ENV		0x04
87#define DRV2667_160_MS_ENV		0x05
88#define DRV2667_192_MS_ENV		0x06
89#define DRV2667_224_MS_ENV		0x07
90#define DRV2667_256_MS_ENV		0x08
91#define DRV2667_512_MS_ENV		0x09
92#define DRV2667_768_MS_ENV		0x0a
93#define DRV2667_1024_MS_ENV		0x0b
94#define DRV2667_1280_MS_ENV		0x0c
95#define DRV2667_1536_MS_ENV		0x0d
96#define DRV2667_1792_MS_ENV		0x0e
97#define DRV2667_2048_MS_ENV		0x0f
98
99/**
100 * struct drv2667_data -
101 * @input_dev - Pointer to the input device
102 * @client - Pointer to the I2C client
103 * @regmap - Register map of the device
104 * @work - Work item used to off load the enable/disable of the vibration
105 * @regulator - Pointer to the regulator for the IC
106 * @magnitude - Magnitude of the vibration event
107**/
108struct drv2667_data {
109	struct input_dev *input_dev;
110	struct i2c_client *client;
111	struct regmap *regmap;
112	struct work_struct work;
113	struct regulator *regulator;
114	u32 page;
115	u32 magnitude;
116	u32 frequency;
117};
118
119static struct reg_default drv2667_reg_defs[] = {
120	{ DRV2667_STATUS, 0x02 },
121	{ DRV2667_CTRL_1, 0x28 },
122	{ DRV2667_CTRL_2, 0x40 },
123	{ DRV2667_WV_SEQ_0, 0x00 },
124	{ DRV2667_WV_SEQ_1, 0x00 },
125	{ DRV2667_WV_SEQ_2, 0x00 },
126	{ DRV2667_WV_SEQ_3, 0x00 },
127	{ DRV2667_WV_SEQ_4, 0x00 },
128	{ DRV2667_WV_SEQ_5, 0x00 },
129	{ DRV2667_WV_SEQ_6, 0x00 },
130	{ DRV2667_WV_SEQ_7, 0x00 },
131	{ DRV2667_FIFO, 0x00 },
132	{ DRV2667_PAGE, 0x00 },
133};
134
135static int drv2667_set_waveform_freq(struct drv2667_data *haptics)
136{
137	unsigned int read_buf;
138	int freq;
139	int error;
140
141	/* Per the data sheet:
142	 * Sinusoid Frequency (Hz) = 7.8125 x Frequency
143	 */
144	freq = (haptics->frequency * 1000) / 78125;
145	if (freq <= 0) {
146		dev_err(&haptics->client->dev,
147			"ERROR: Frequency calculated to %i\n", freq);
148		return -EINVAL;
149	}
150
151	error = regmap_read(haptics->regmap, DRV2667_PAGE, &read_buf);
152	if (error) {
153		dev_err(&haptics->client->dev,
154			"Failed to read the page number: %d\n", error);
155		return -EIO;
156	}
157
158	if (read_buf == DRV2667_PAGE_0 ||
159		haptics->page != read_buf) {
160		error = regmap_write(haptics->regmap,
161				DRV2667_PAGE, haptics->page);
162		if (error) {
163			dev_err(&haptics->client->dev,
164				"Failed to set the page: %d\n", error);
165			return -EIO;
166		}
167	}
168
169	error = regmap_write(haptics->regmap, DRV2667_RAM_FREQ,	freq);
170	if (error)
171		dev_err(&haptics->client->dev,
172				"Failed to set the frequency: %d\n", error);
173
174	/* Reset back to original page */
175	if (read_buf == DRV2667_PAGE_0 ||
176		haptics->page != read_buf) {
177		error = regmap_write(haptics->regmap, DRV2667_PAGE, read_buf);
178		if (error) {
179			dev_err(&haptics->client->dev,
180					"Failed to set the page: %d\n", error);
181				return -EIO;
182			}
183	}
184
185	return error;
186}
187
188static void drv2667_worker(struct work_struct *work)
189{
190	struct drv2667_data *haptics = container_of(work, struct drv2667_data, work);
191	int error;
192
193	if (haptics->magnitude) {
194		error = regmap_write(haptics->regmap,
195				DRV2667_PAGE, haptics->page);
196		if (error) {
197			dev_err(&haptics->client->dev,
198				"Failed to set the page: %d\n", error);
199			return;
200		}
201
202		error = regmap_write(haptics->regmap, DRV2667_RAM_AMP,
203				haptics->magnitude);
204		if (error) {
205			dev_err(&haptics->client->dev,
206				"Failed to set the amplitude: %d\n", error);
207			return;
208		}
209
210		error = regmap_write(haptics->regmap,
211				DRV2667_PAGE, DRV2667_PAGE_0);
212		if (error) {
213			dev_err(&haptics->client->dev,
214				"Failed to set the page: %d\n", error);
215			return;
216		}
217
218		error = regmap_write(haptics->regmap,
219				DRV2667_CTRL_2, DRV2667_GO);
220		if (error) {
221			dev_err(&haptics->client->dev,
222				"Failed to set the GO bit: %d\n", error);
223		}
224	} else {
225		error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
226				DRV2667_GO, 0);
227		if (error) {
228			dev_err(&haptics->client->dev,
229				"Failed to unset the GO bit: %d\n", error);
230		}
231	}
232}
233
234static int drv2667_haptics_play(struct input_dev *input, void *data,
235				struct ff_effect *effect)
236{
237	struct drv2667_data *haptics = input_get_drvdata(input);
238
239	if (effect->u.rumble.strong_magnitude > 0)
240		haptics->magnitude = effect->u.rumble.strong_magnitude;
241	else if (effect->u.rumble.weak_magnitude > 0)
242		haptics->magnitude = effect->u.rumble.weak_magnitude;
243	else
244		haptics->magnitude = 0;
245
246	schedule_work(&haptics->work);
247
248	return 0;
249}
250
251static void drv2667_close(struct input_dev *input)
252{
253	struct drv2667_data *haptics = input_get_drvdata(input);
254	int error;
255
256	cancel_work_sync(&haptics->work);
257
258	error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
259				DRV2667_STANDBY, 1);
260	if (error)
261		dev_err(&haptics->client->dev,
262			"Failed to enter standby mode: %d\n", error);
263}
264
265static const struct reg_default drv2667_init_regs[] = {
266	{ DRV2667_CTRL_2, 0 },
267	{ DRV2667_CTRL_1, DRV2667_25_VPP_GAIN },
268	{ DRV2667_WV_SEQ_0, 1 },
269	{ DRV2667_WV_SEQ_1, 0 }
270};
271
272static const struct reg_default drv2667_page1_init[] = {
273	{ DRV2667_RAM_HDR_SZ, 0x05 },
274	{ DRV2667_RAM_START_HI, 0x80 },
275	{ DRV2667_RAM_START_LO, 0x06 },
276	{ DRV2667_RAM_STOP_HI, 0x00 },
277	{ DRV2667_RAM_STOP_LO, 0x09 },
278	{ DRV2667_RAM_REPEAT_CT, 0 },
279	{ DRV2667_RAM_DURATION, 0x05 },
280	{ DRV2667_RAM_ENVELOPE, DRV2667_NO_ENV },
281	{ DRV2667_RAM_AMP, 0x60 },
282};
283
284static int drv2667_init(struct drv2667_data *haptics)
285{
286	int error;
287
288	/* Set default haptic frequency to 195Hz on Page 1*/
289	haptics->frequency = 195;
290	haptics->page = DRV2667_PAGE_1;
291
292	error = regmap_register_patch(haptics->regmap,
293				      drv2667_init_regs,
294				      ARRAY_SIZE(drv2667_init_regs));
295	if (error) {
296		dev_err(&haptics->client->dev,
297			"Failed to write init registers: %d\n",
298			error);
299		return error;
300	}
301
302	error = regmap_write(haptics->regmap, DRV2667_PAGE, haptics->page);
303	if (error) {
304		dev_err(&haptics->client->dev, "Failed to set page: %d\n",
305			error);
306		goto error_out;
307	}
308
309	error = drv2667_set_waveform_freq(haptics);
310	if (error)
311		goto error_page;
312
313	error = regmap_register_patch(haptics->regmap,
314				      drv2667_page1_init,
315				      ARRAY_SIZE(drv2667_page1_init));
316	if (error) {
317		dev_err(&haptics->client->dev,
318			"Failed to write page registers: %d\n",
319			error);
320		return error;
321	}
322
323	error = regmap_write(haptics->regmap, DRV2667_PAGE, DRV2667_PAGE_0);
324	return error;
325
326error_page:
327	regmap_write(haptics->regmap, DRV2667_PAGE, DRV2667_PAGE_0);
328error_out:
329	return error;
330}
331
332static const struct regmap_config drv2667_regmap_config = {
333	.reg_bits = 8,
334	.val_bits = 8,
335
336	.max_register = DRV2667_MAX_REG,
337	.reg_defaults = drv2667_reg_defs,
338	.num_reg_defaults = ARRAY_SIZE(drv2667_reg_defs),
339	.cache_type = REGCACHE_NONE,
340};
341
342static int drv2667_probe(struct i2c_client *client,
343			 const struct i2c_device_id *id)
344{
345	struct drv2667_data *haptics;
346	int error;
347
348	haptics = devm_kzalloc(&client->dev, sizeof(*haptics), GFP_KERNEL);
349	if (!haptics)
350		return -ENOMEM;
351
352	haptics->regulator = devm_regulator_get(&client->dev, "vbat");
353	if (IS_ERR(haptics->regulator)) {
354		error = PTR_ERR(haptics->regulator);
355		dev_err(&client->dev,
356			"unable to get regulator, error: %d\n", error);
357		return error;
358	}
359
360	haptics->input_dev = devm_input_allocate_device(&client->dev);
361	if (!haptics->input_dev) {
362		dev_err(&client->dev, "Failed to allocate input device\n");
363		return -ENOMEM;
364	}
365
366	haptics->input_dev->name = "drv2667:haptics";
367	haptics->input_dev->dev.parent = client->dev.parent;
368	haptics->input_dev->close = drv2667_close;
369	input_set_drvdata(haptics->input_dev, haptics);
370	input_set_capability(haptics->input_dev, EV_FF, FF_RUMBLE);
371
372	error = input_ff_create_memless(haptics->input_dev, NULL,
373					drv2667_haptics_play);
374	if (error) {
375		dev_err(&client->dev, "input_ff_create() failed: %d\n",
376			error);
377		return error;
378	}
379
380	INIT_WORK(&haptics->work, drv2667_worker);
381
382	haptics->client = client;
383	i2c_set_clientdata(client, haptics);
384
385	haptics->regmap = devm_regmap_init_i2c(client, &drv2667_regmap_config);
386	if (IS_ERR(haptics->regmap)) {
387		error = PTR_ERR(haptics->regmap);
388		dev_err(&client->dev, "Failed to allocate register map: %d\n",
389			error);
390		return error;
391	}
392
393	error = drv2667_init(haptics);
394	if (error) {
395		dev_err(&client->dev, "Device init failed: %d\n", error);
396		return error;
397	}
398
399	error = input_register_device(haptics->input_dev);
400	if (error) {
401		dev_err(&client->dev, "couldn't register input device: %d\n",
402			error);
403		return error;
404	}
405
406	return 0;
407}
408
409static int __maybe_unused drv2667_suspend(struct device *dev)
410{
411	struct drv2667_data *haptics = dev_get_drvdata(dev);
412	int ret = 0;
413
414	mutex_lock(&haptics->input_dev->mutex);
415
416	if (haptics->input_dev->users) {
417		ret = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
418				DRV2667_STANDBY, 1);
419		if (ret) {
420			dev_err(dev, "Failed to set standby mode\n");
421			regulator_disable(haptics->regulator);
422			goto out;
423		}
424
425		ret = regulator_disable(haptics->regulator);
426		if (ret) {
427			dev_err(dev, "Failed to disable regulator\n");
428			regmap_update_bits(haptics->regmap,
429					   DRV2667_CTRL_2,
430					   DRV2667_STANDBY, 0);
431		}
432	}
433out:
434	mutex_unlock(&haptics->input_dev->mutex);
435	return ret;
436}
437
438static int __maybe_unused drv2667_resume(struct device *dev)
439{
440	struct drv2667_data *haptics = dev_get_drvdata(dev);
441	int ret = 0;
442
443	mutex_lock(&haptics->input_dev->mutex);
444
445	if (haptics->input_dev->users) {
446		ret = regulator_enable(haptics->regulator);
447		if (ret) {
448			dev_err(dev, "Failed to enable regulator\n");
449			goto out;
450		}
451
452		ret = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
453					 DRV2667_STANDBY, 0);
454		if (ret) {
455			dev_err(dev, "Failed to unset standby mode\n");
456			regulator_disable(haptics->regulator);
457			goto out;
458		}
459
460	}
461
462out:
463	mutex_unlock(&haptics->input_dev->mutex);
464	return ret;
465}
466
467static SIMPLE_DEV_PM_OPS(drv2667_pm_ops, drv2667_suspend, drv2667_resume);
468
469static const struct i2c_device_id drv2667_id[] = {
470	{ "drv2667", 0 },
471	{ }
472};
473MODULE_DEVICE_TABLE(i2c, drv2667_id);
474
475#ifdef CONFIG_OF
476static const struct of_device_id drv2667_of_match[] = {
477	{ .compatible = "ti,drv2667", },
478	{ }
479};
480MODULE_DEVICE_TABLE(of, drv2667_of_match);
481#endif
482
483static struct i2c_driver drv2667_driver = {
484	.probe		= drv2667_probe,
485	.driver		= {
486		.name	= "drv2667-haptics",
487		.owner	= THIS_MODULE,
488		.of_match_table = of_match_ptr(drv2667_of_match),
489		.pm	= &drv2667_pm_ops,
490	},
491	.id_table = drv2667_id,
492};
493module_i2c_driver(drv2667_driver);
494
495MODULE_DESCRIPTION("TI DRV2667 haptics driver");
496MODULE_LICENSE("GPL");
497MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
498