summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/hycon-hy46xx.c
blob: 2450cfa14de9dfe67657657399588241d4dfc636 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2021
 * Author(s): Giulio Benetti <giulio.benetti@benettiengineering.com>
 */

#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/irq.h>
#include <linux/regulator/consumer.h>
#include <linux/regmap.h>

#include <asm/unaligned.h>

#define HY46XX_CHKSUM_CODE		0x1
#define HY46XX_FINGER_NUM		0x2
#define HY46XX_CHKSUM_LEN		0x7
#define HY46XX_THRESHOLD		0x80
#define HY46XX_GLOVE_EN			0x84
#define HY46XX_REPORT_SPEED		0x88
#define HY46XX_PWR_NOISE_EN		0x89
#define HY46XX_FILTER_DATA		0x8A
#define HY46XX_GAIN			0x92
#define HY46XX_EDGE_OFFSET		0x93
#define HY46XX_RX_NR_USED		0x94
#define HY46XX_TX_NR_USED		0x95
#define HY46XX_PWR_MODE			0xA5
#define HY46XX_FW_VERSION		0xA6
#define HY46XX_LIB_VERSION		0xA7
#define HY46XX_TP_INFO			0xA8
#define HY46XX_TP_CHIP_ID		0xA9
#define HY46XX_BOOT_VER			0xB0

#define HY46XX_TPLEN			0x6
#define HY46XX_REPORT_PKT_LEN		0x44

#define HY46XX_MAX_SUPPORTED_POINTS	11

#define TOUCH_EVENT_DOWN		0x00
#define TOUCH_EVENT_UP			0x01
#define TOUCH_EVENT_CONTACT		0x02
#define TOUCH_EVENT_RESERVED		0x03

struct hycon_hy46xx_data {
	struct i2c_client *client;
	struct input_dev *input;
	struct touchscreen_properties prop;
	struct regulator *vcc;

	struct gpio_desc *reset_gpio;

	struct mutex mutex;
	struct regmap *regmap;

	int threshold;
	bool glove_enable;
	int report_speed;
	bool noise_filter_enable;
	int filter_data;
	int gain;
	int edge_offset;
	int rx_number_used;
	int tx_number_used;
	int power_mode;
	int fw_version;
	int lib_version;
	int tp_information;
	int tp_chip_id;
	int bootloader_version;
};

static const struct regmap_config hycon_hy46xx_i2c_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};

static bool hycon_hy46xx_check_checksum(struct hycon_hy46xx_data *tsdata, u8 *buf)
{
	u8 chksum = 0;
	int i;

	for (i = 2; i < buf[HY46XX_CHKSUM_LEN]; i++)
		chksum += buf[i];

	if (chksum == buf[HY46XX_CHKSUM_CODE])
		return true;

	dev_err_ratelimited(&tsdata->client->dev,
			    "checksum error: 0x%02x expected, got 0x%02x\n",
			    chksum, buf[HY46XX_CHKSUM_CODE]);

	return false;
}

static irqreturn_t hycon_hy46xx_isr(int irq, void *dev_id)
{
	struct hycon_hy46xx_data *tsdata = dev_id;
	struct device *dev = &tsdata->client->dev;
	u8 rdbuf[HY46XX_REPORT_PKT_LEN];
	int i, x, y, id;
	int error;

	memset(rdbuf, 0, sizeof(rdbuf));

	error = regmap_bulk_read(tsdata->regmap, 0, rdbuf, sizeof(rdbuf));
	if (error) {
		dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n",
				    error);
		goto out;
	}

	if (!hycon_hy46xx_check_checksum(tsdata, rdbuf))
		goto out;

	for (i = 0; i < HY46XX_MAX_SUPPORTED_POINTS; i++) {
		u8 *buf = &rdbuf[3 + (HY46XX_TPLEN * i)];
		int type = buf[0] >> 6;

		if (type == TOUCH_EVENT_RESERVED)
			continue;

		x = get_unaligned_be16(buf) & 0x0fff;
		y = get_unaligned_be16(buf + 2) & 0x0fff;

		id = buf[2] >> 4;

		input_mt_slot(tsdata->input, id);
		if (input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER,
					       type != TOUCH_EVENT_UP))
			touchscreen_report_pos(tsdata->input, &tsdata->prop,
					       x, y, true);
	}

	input_mt_report_pointer_emulation(tsdata->input, false);
	input_sync(tsdata->input);

out:
	return IRQ_HANDLED;
}

struct hycon_hy46xx_attribute {
	struct device_attribute dattr;
	size_t field_offset;
	u8 address;
	u8 limit_low;
	u8 limit_high;
};

#define HYCON_ATTR_U8(_field, _mode, _address, _limit_low, _limit_high)	\
	struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = {		\
		.dattr = __ATTR(_field, _mode,				\
				hycon_hy46xx_setting_show,			\
				hycon_hy46xx_setting_store),			\
		.field_offset = offsetof(struct hycon_hy46xx_data, _field),	\
		.address = _address,					\
		.limit_low = _limit_low,				\
		.limit_high = _limit_high,				\
	}

#define HYCON_ATTR_BOOL(_field, _mode, _address)			\
	struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = {		\
		.dattr = __ATTR(_field, _mode,				\
				hycon_hy46xx_setting_show,			\
				hycon_hy46xx_setting_store),			\
		.field_offset = offsetof(struct hycon_hy46xx_data, _field),	\
		.address = _address,					\
		.limit_low = false,					\
		.limit_high = true,					\
	}

static ssize_t hycon_hy46xx_setting_show(struct device *dev,
				   struct device_attribute *dattr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client);
	struct hycon_hy46xx_attribute *attr =
			container_of(dattr, struct hycon_hy46xx_attribute, dattr);
	u8 *field = (u8 *)tsdata + attr->field_offset;
	size_t count = 0;
	int error = 0;
	int val;

	mutex_lock(&tsdata->mutex);

	error = regmap_read(tsdata->regmap, attr->address, &val);
	if (error < 0) {
		dev_err(&tsdata->client->dev,
			"Failed to fetch attribute %s, error %d\n",
			dattr->attr.name, error);
		goto out;
	}

	if (val != *field) {
		dev_warn(&tsdata->client->dev,
			 "%s: read (%d) and stored value (%d) differ\n",
			 dattr->attr.name, val, *field);
		*field = val;
	}

	count = scnprintf(buf, PAGE_SIZE, "%d\n", val);

out:
	mutex_unlock(&tsdata->mutex);
	return error ?: count;
}

static ssize_t hycon_hy46xx_setting_store(struct device *dev,
					struct device_attribute *dattr,
					const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client);
	struct hycon_hy46xx_attribute *attr =
			container_of(dattr, struct hycon_hy46xx_attribute, dattr);
	u8 *field = (u8 *)tsdata + attr->field_offset;
	unsigned int val;
	int error;

	mutex_lock(&tsdata->mutex);

	error = kstrtouint(buf, 0, &val);
	if (error)
		goto out;

	if (val < attr->limit_low || val > attr->limit_high) {
		error = -ERANGE;
		goto out;
	}

	error = regmap_write(tsdata->regmap, attr->address, val);
	if (error < 0) {
		dev_err(&tsdata->client->dev,
			"Failed to update attribute %s, error: %d\n",
			dattr->attr.name, error);
		goto out;
	}
	*field = val;

out:
	mutex_unlock(&tsdata->mutex);
	return error ?: count;
}

static HYCON_ATTR_U8(threshold, 0644, HY46XX_THRESHOLD, 0, 255);
static HYCON_ATTR_BOOL(glove_enable, 0644, HY46XX_GLOVE_EN);
static HYCON_ATTR_U8(report_speed, 0644, HY46XX_REPORT_SPEED, 0, 255);
static HYCON_ATTR_BOOL(noise_filter_enable, 0644, HY46XX_PWR_NOISE_EN);
static HYCON_ATTR_U8(filter_data, 0644, HY46XX_FILTER_DATA, 0, 5);
static HYCON_ATTR_U8(gain, 0644, HY46XX_GAIN, 0, 5);
static HYCON_ATTR_U8(edge_offset, 0644, HY46XX_EDGE_OFFSET, 0, 5);
static HYCON_ATTR_U8(fw_version, 0444, HY46XX_FW_VERSION, 0, 255);
static HYCON_ATTR_U8(lib_version, 0444, HY46XX_LIB_VERSION, 0, 255);
static HYCON_ATTR_U8(tp_information, 0444, HY46XX_TP_INFO, 0, 255);
static HYCON_ATTR_U8(tp_chip_id, 0444, HY46XX_TP_CHIP_ID, 0, 255);
static HYCON_ATTR_U8(bootloader_version, 0444, HY46XX_BOOT_VER, 0, 255);

static struct attribute *hycon_hy46xx_attrs[] = {
	&hycon_hy46xx_attr_threshold.dattr.attr,
	&hycon_hy46xx_attr_glove_enable.dattr.attr,
	&hycon_hy46xx_attr_report_speed.dattr.attr,
	&hycon_hy46xx_attr_noise_filter_enable.dattr.attr,
	&hycon_hy46xx_attr_filter_data.dattr.attr,
	&hycon_hy46xx_attr_gain.dattr.attr,
	&hycon_hy46xx_attr_edge_offset.dattr.attr,
	&hycon_hy46xx_attr_fw_version.dattr.attr,
	&hycon_hy46xx_attr_lib_version.dattr.attr,
	&hycon_hy46xx_attr_tp_information.dattr.attr,
	&hycon_hy46xx_attr_tp_chip_id.dattr.attr,
	&hycon_hy46xx_attr_bootloader_version.dattr.attr,
	NULL
};

static const struct attribute_group hycon_hy46xx_attr_group = {
	.attrs = hycon_hy46xx_attrs,
};

static void hycon_hy46xx_get_defaults(struct device *dev, struct hycon_hy46xx_data *tsdata)
{
	bool val_bool;
	int error;
	u32 val;

	error = device_property_read_u32(dev, "hycon,threshold", &val);
	if (!error) {
		error = regmap_write(tsdata->regmap, HY46XX_THRESHOLD, val);
		if (error < 0)
			goto out;

		tsdata->threshold = val;
	}

	val_bool = device_property_read_bool(dev, "hycon,glove-enable");
	error = regmap_write(tsdata->regmap, HY46XX_GLOVE_EN, val_bool);
	if (error < 0)
		goto out;
	tsdata->glove_enable = val_bool;

	error = device_property_read_u32(dev, "hycon,report-speed-hz", &val);
	if (!error) {
		error = regmap_write(tsdata->regmap, HY46XX_REPORT_SPEED, val);
		if (error < 0)
			goto out;

		tsdata->report_speed = val;
	}

	val_bool = device_property_read_bool(dev, "hycon,noise-filter-enable");
	error = regmap_write(tsdata->regmap, HY46XX_PWR_NOISE_EN, val_bool);
	if (error < 0)
		goto out;
	tsdata->noise_filter_enable = val_bool;

	error = device_property_read_u32(dev, "hycon,filter-data", &val);
	if (!error) {
		error = regmap_write(tsdata->regmap, HY46XX_FILTER_DATA, val);
		if (error < 0)
			goto out;

		tsdata->filter_data = val;
	}

	error = device_property_read_u32(dev, "hycon,gain", &val);
	if (!error) {
		error = regmap_write(tsdata->regmap, HY46XX_GAIN, val);
		if (error < 0)
			goto out;

		tsdata->gain = val;
	}

	error = device_property_read_u32(dev, "hycon,edge-offset", &val);
	if (!error) {
		error = regmap_write(tsdata->regmap, HY46XX_EDGE_OFFSET, val);
		if (error < 0)
			goto out;

		tsdata->edge_offset = val;
	}

	return;
out:
	dev_err(&tsdata->client->dev, "Failed to set default settings");
}

static void hycon_hy46xx_get_parameters(struct hycon_hy46xx_data *tsdata)
{
	int error;
	u32 val;

	error = regmap_read(tsdata->regmap, HY46XX_THRESHOLD, &val);
	if (error < 0)
		goto out;
	tsdata->threshold = val;

	error = regmap_read(tsdata->regmap, HY46XX_GLOVE_EN, &val);
	if (error < 0)
		goto out;
	tsdata->glove_enable = val;

	error = regmap_read(tsdata->regmap, HY46XX_REPORT_SPEED, &val);
	if (error < 0)
		goto out;
	tsdata->report_speed = val;

	error = regmap_read(tsdata->regmap, HY46XX_PWR_NOISE_EN, &val);
	if (error < 0)
		goto out;
	tsdata->noise_filter_enable = val;

	error = regmap_read(tsdata->regmap, HY46XX_FILTER_DATA, &val);
	if (error < 0)
		goto out;
	tsdata->filter_data = val;

	error = regmap_read(tsdata->regmap, HY46XX_GAIN, &val);
	if (error < 0)
		goto out;
	tsdata->gain = val;

	error = regmap_read(tsdata->regmap, HY46XX_EDGE_OFFSET, &val);
	if (error < 0)
		goto out;
	tsdata->edge_offset = val;

	error = regmap_read(tsdata->regmap, HY46XX_RX_NR_USED, &val);
	if (error < 0)
		goto out;
	tsdata->rx_number_used = val;

	error = regmap_read(tsdata->regmap, HY46XX_TX_NR_USED, &val);
	if (error < 0)
		goto out;
	tsdata->tx_number_used = val;

	error = regmap_read(tsdata->regmap, HY46XX_PWR_MODE, &val);
	if (error < 0)
		goto out;
	tsdata->power_mode = val;

	error = regmap_read(tsdata->regmap, HY46XX_FW_VERSION, &val);
	if (error < 0)
		goto out;
	tsdata->fw_version = val;

	error = regmap_read(tsdata->regmap, HY46XX_LIB_VERSION, &val);
	if (error < 0)
		goto out;
	tsdata->lib_version = val;

	error = regmap_read(tsdata->regmap, HY46XX_TP_INFO, &val);
	if (error < 0)
		goto out;
	tsdata->tp_information = val;

	error = regmap_read(tsdata->regmap, HY46XX_TP_CHIP_ID, &val);
	if (error < 0)
		goto out;
	tsdata->tp_chip_id = val;

	error = regmap_read(tsdata->regmap, HY46XX_BOOT_VER, &val);
	if (error < 0)
		goto out;
	tsdata->bootloader_version = val;

	return;
out:
	dev_err(&tsdata->client->dev, "Failed to read default settings");
}

static void hycon_hy46xx_disable_regulator(void *arg)
{
	struct hycon_hy46xx_data *data = arg;

	regulator_disable(data->vcc);
}

static int hycon_hy46xx_probe(struct i2c_client *client)
{
	struct hycon_hy46xx_data *tsdata;
	struct input_dev *input;
	int error;

	dev_dbg(&client->dev, "probing for HYCON HY46XX I2C\n");

	tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL);
	if (!tsdata)
		return -ENOMEM;

	tsdata->vcc = devm_regulator_get(&client->dev, "vcc");
	if (IS_ERR(tsdata->vcc)) {
		error = PTR_ERR(tsdata->vcc);
		if (error != -EPROBE_DEFER)
			dev_err(&client->dev,
				"failed to request regulator: %d\n", error);
		return error;
	}

	error = regulator_enable(tsdata->vcc);
	if (error < 0) {
		dev_err(&client->dev, "failed to enable vcc: %d\n", error);
		return error;
	}

	error = devm_add_action_or_reset(&client->dev,
					 hycon_hy46xx_disable_regulator,
					 tsdata);
	if (error)
		return error;

	tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev,
						     "reset", GPIOD_OUT_LOW);
	if (IS_ERR(tsdata->reset_gpio)) {
		error = PTR_ERR(tsdata->reset_gpio);
		dev_err(&client->dev,
			"Failed to request GPIO reset pin, error %d\n", error);
		return error;
	}

	if (tsdata->reset_gpio) {
		usleep_range(5000, 6000);
		gpiod_set_value_cansleep(tsdata->reset_gpio, 1);
		usleep_range(5000, 6000);
		gpiod_set_value_cansleep(tsdata->reset_gpio, 0);
		msleep(1000);
	}

	input = devm_input_allocate_device(&client->dev);
	if (!input) {
		dev_err(&client->dev, "failed to allocate input device.\n");
		return -ENOMEM;
	}

	mutex_init(&tsdata->mutex);
	tsdata->client = client;
	tsdata->input = input;

	tsdata->regmap = devm_regmap_init_i2c(client,
					      &hycon_hy46xx_i2c_regmap_config);
	if (IS_ERR(tsdata->regmap)) {
		dev_err(&client->dev, "regmap allocation failed\n");
		return PTR_ERR(tsdata->regmap);
	}

	hycon_hy46xx_get_defaults(&client->dev, tsdata);
	hycon_hy46xx_get_parameters(tsdata);

	input->name = "Hycon Capacitive Touch";
	input->id.bustype = BUS_I2C;
	input->dev.parent = &client->dev;

	input_set_abs_params(input, ABS_MT_POSITION_X, 0, -1, 0, 0);
	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, -1, 0, 0);

	touchscreen_parse_properties(input, true, &tsdata->prop);

	error = input_mt_init_slots(input, HY46XX_MAX_SUPPORTED_POINTS,
				    INPUT_MT_DIRECT);
	if (error) {
		dev_err(&client->dev, "Unable to init MT slots.\n");
		return error;
	}

	i2c_set_clientdata(client, tsdata);

	error = devm_request_threaded_irq(&client->dev, client->irq,
					  NULL, hycon_hy46xx_isr, IRQF_ONESHOT,
					  client->name, tsdata);
	if (error) {
		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
		return error;
	}

	error = devm_device_add_group(&client->dev, &hycon_hy46xx_attr_group);
	if (error)
		return error;

	error = input_register_device(input);
	if (error)
		return error;

	dev_dbg(&client->dev,
		"HYCON HY46XX initialized: IRQ %d, Reset pin %d.\n",
		client->irq,
		tsdata->reset_gpio ? desc_to_gpio(tsdata->reset_gpio) : -1);

	return 0;
}

static const struct i2c_device_id hycon_hy46xx_id[] = {
	{ .name = "hy4613" },
	{ .name = "hy4614" },
	{ .name = "hy4621" },
	{ .name = "hy4623" },
	{ .name = "hy4633" },
	{ .name = "hy4635" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, hycon_hy46xx_id);

static const struct of_device_id hycon_hy46xx_of_match[] = {
	{ .compatible = "hycon,hy4613" },
	{ .compatible = "hycon,hy4614" },
	{ .compatible = "hycon,hy4621" },
	{ .compatible = "hycon,hy4623" },
	{ .compatible = "hycon,hy4633" },
	{ .compatible = "hycon,hy4635" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, hycon_hy46xx_of_match);

static struct i2c_driver hycon_hy46xx_driver = {
	.driver = {
		.name = "hycon_hy46xx",
		.of_match_table = hycon_hy46xx_of_match,
		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
	},
	.id_table = hycon_hy46xx_id,
	.probe = hycon_hy46xx_probe,
};

module_i2c_driver(hycon_hy46xx_driver);

MODULE_AUTHOR("Giulio Benetti <giulio.benetti@benettiengineering.com>");
MODULE_DESCRIPTION("HYCON HY46XX I2C Touchscreen Driver");
MODULE_LICENSE("GPL v2");