summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/sx8654.c
blob: de85e57b248605957bb7290d770fa7d1ee708f0a (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for Semtech SX8654 I2C touchscreen controller.
 *
 * Copyright (c) 2015 Armadeus Systems
 *	Sébastien Szymanski <sebastien.szymanski@armadeus.com>
 *
 * Using code from:
 *  - sx865x.c
 *	Copyright (c) 2013 U-MoBo Srl
 *	Pierluigi Passaro <p.passaro@u-mobo.com>
 *  - sx8650.c
 *      Copyright (c) 2009 Wayne Roberts
 *  - tsc2007.c
 *      Copyright (c) 2008 Kwangwoo Lee
 *  - ads7846.c
 *      Copyright (c) 2005 David Brownell
 *      Copyright (c) 2006 Nokia Corporation
 *  - corgi_ts.c
 *      Copyright (C) 2004-2005 Richard Purdie
 *  - omap_ts.[hc], ads7846.h, ts_osk.c
 *      Copyright (C) 2002 MontaVista Software
 *      Copyright (C) 2004 Texas Instruments
 *      Copyright (C) 2005 Dirk Behme
 */

#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>

/* register addresses */
#define I2C_REG_TOUCH0			0x00
#define I2C_REG_TOUCH1			0x01
#define I2C_REG_CHANMASK		0x04
#define I2C_REG_IRQMASK			0x22
#define I2C_REG_IRQSRC			0x23
#define I2C_REG_SOFTRESET		0x3f

#define I2C_REG_SX8650_STAT		0x05
#define SX8650_STAT_CONVIRQ		BIT(7)

/* commands */
#define CMD_READ_REGISTER		0x40
#define CMD_PENTRG			0xe0

/* value for I2C_REG_SOFTRESET */
#define SOFTRESET_VALUE			0xde

/* bits for I2C_REG_IRQSRC */
#define IRQ_PENTOUCH_TOUCHCONVDONE	BIT(3)
#define IRQ_PENRELEASE			BIT(2)

/* bits for RegTouch1 */
#define CONDIRQ				0x20
#define RPDNT_100K			0x00
#define FILT_7SA			0x03

/* bits for I2C_REG_CHANMASK */
#define CONV_X				BIT(7)
#define CONV_Y				BIT(6)

/* coordinates rate: higher nibble of CTRL0 register */
#define RATE_MANUAL			0x00
#define RATE_5000CPS			0xf0

/* power delay: lower nibble of CTRL0 register */
#define POWDLY_1_1MS			0x0b

/* for sx8650, as we have no pen release IRQ there: timeout in ns following the
 * last PENIRQ after which we assume the pen is lifted.
 */
#define SX8650_PENIRQ_TIMEOUT		msecs_to_jiffies(10)

#define MAX_12BIT			((1 << 12) - 1)
#define MAX_I2C_READ_LEN		10 /* see datasheet section 5.1.5 */

/* channel definition */
#define CH_X				0x00
#define CH_Y				0x01

struct sx865x_data {
	u8 cmd_manual;
	u8 chan_mask;
	bool has_irq_penrelease;
	bool has_reg_irqmask;
	irq_handler_t irqh;
};

struct sx8654 {
	struct input_dev *input;
	struct i2c_client *client;
	struct gpio_desc *gpio_reset;

	spinlock_t lock;	/* for input reporting from irq/timer */
	struct timer_list timer;

	struct touchscreen_properties props;

	const struct sx865x_data *data;
};

static inline void sx865x_penrelease(struct sx8654 *ts)
{
	struct input_dev *input_dev = ts->input;

	input_report_key(input_dev, BTN_TOUCH, 0);
	input_sync(input_dev);
}

static void sx865x_penrelease_timer_handler(struct timer_list *t)
{
	struct sx8654 *ts = from_timer(ts, t, timer);
	unsigned long flags;

	spin_lock_irqsave(&ts->lock, flags);
	sx865x_penrelease(ts);
	spin_unlock_irqrestore(&ts->lock, flags);
	dev_dbg(&ts->client->dev, "penrelease by timer\n");
}

static irqreturn_t sx8650_irq(int irq, void *handle)
{
	struct sx8654 *ts = handle;
	struct device *dev = &ts->client->dev;
	int len, i;
	unsigned long flags;
	u8 stat;
	u16 x, y;
	u16 ch;
	u16 chdata;
	__be16 data[MAX_I2C_READ_LEN / sizeof(__be16)];
	u8 nchan = hweight32(ts->data->chan_mask);
	u8 readlen = nchan * sizeof(*data);

	stat = i2c_smbus_read_byte_data(ts->client, CMD_READ_REGISTER
						    | I2C_REG_SX8650_STAT);

	if (!(stat & SX8650_STAT_CONVIRQ)) {
		dev_dbg(dev, "%s ignore stat [0x%02x]", __func__, stat);
		return IRQ_HANDLED;
	}

	len = i2c_master_recv(ts->client, (u8 *)data, readlen);
	if (len != readlen) {
		dev_dbg(dev, "ignore short recv (%d)\n", len);
		return IRQ_HANDLED;
	}

	spin_lock_irqsave(&ts->lock, flags);

	x = 0;
	y = 0;
	for (i = 0; i < nchan; i++) {
		chdata = be16_to_cpu(data[i]);

		if (unlikely(chdata == 0xFFFF)) {
			dev_dbg(dev, "invalid qualified data @ %d\n", i);
			continue;
		} else if (unlikely(chdata & 0x8000)) {
			dev_warn(dev, "hibit @ %d [0x%04x]\n", i, chdata);
			continue;
		}

		ch = chdata >> 12;
		if (ch == CH_X)
			x = chdata & MAX_12BIT;
		else if (ch == CH_Y)
			y = chdata & MAX_12BIT;
		else
			dev_warn(dev, "unknown channel %d [0x%04x]\n", ch,
				 chdata);
	}

	touchscreen_report_pos(ts->input, &ts->props, x, y, false);
	input_report_key(ts->input, BTN_TOUCH, 1);
	input_sync(ts->input);
	dev_dbg(dev, "point(%4d,%4d)\n", x, y);

	mod_timer(&ts->timer, jiffies + SX8650_PENIRQ_TIMEOUT);
	spin_unlock_irqrestore(&ts->lock, flags);

	return IRQ_HANDLED;
}

static irqreturn_t sx8654_irq(int irq, void *handle)
{
	struct sx8654 *sx8654 = handle;
	int irqsrc;
	u8 data[4];
	unsigned int x, y;
	int retval;

	irqsrc = i2c_smbus_read_byte_data(sx8654->client,
					  CMD_READ_REGISTER | I2C_REG_IRQSRC);
	dev_dbg(&sx8654->client->dev, "irqsrc = 0x%x", irqsrc);

	if (irqsrc < 0)
		goto out;

	if (irqsrc & IRQ_PENRELEASE) {
		dev_dbg(&sx8654->client->dev, "pen release interrupt");

		input_report_key(sx8654->input, BTN_TOUCH, 0);
		input_sync(sx8654->input);
	}

	if (irqsrc & IRQ_PENTOUCH_TOUCHCONVDONE) {
		dev_dbg(&sx8654->client->dev, "pen touch interrupt");

		retval = i2c_master_recv(sx8654->client, data, sizeof(data));
		if (retval != sizeof(data))
			goto out;

		/* invalid data */
		if (unlikely(data[0] & 0x80 || data[2] & 0x80))
			goto out;

		x = ((data[0] & 0xf) << 8) | (data[1]);
		y = ((data[2] & 0xf) << 8) | (data[3]);

		touchscreen_report_pos(sx8654->input, &sx8654->props, x, y,
				       false);
		input_report_key(sx8654->input, BTN_TOUCH, 1);
		input_sync(sx8654->input);

		dev_dbg(&sx8654->client->dev, "point(%4d,%4d)\n", x, y);
	}

out:
	return IRQ_HANDLED;
}

static int sx8654_reset(struct sx8654 *ts)
{
	int err;

	if (ts->gpio_reset) {
		gpiod_set_value_cansleep(ts->gpio_reset, 1);
		udelay(2); /* Tpulse > 1µs */
		gpiod_set_value_cansleep(ts->gpio_reset, 0);
	} else {
		dev_dbg(&ts->client->dev, "NRST unavailable, try softreset\n");
		err = i2c_smbus_write_byte_data(ts->client, I2C_REG_SOFTRESET,
						SOFTRESET_VALUE);
		if (err)
			return err;
	}

	return 0;
}

static int sx8654_open(struct input_dev *dev)
{
	struct sx8654 *sx8654 = input_get_drvdata(dev);
	struct i2c_client *client = sx8654->client;
	int error;

	/* enable pen trigger mode */
	error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0,
					  RATE_5000CPS | POWDLY_1_1MS);
	if (error) {
		dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
		return error;
	}

	error = i2c_smbus_write_byte(client, CMD_PENTRG);
	if (error) {
		dev_err(&client->dev, "writing command CMD_PENTRG failed");
		return error;
	}

	enable_irq(client->irq);

	return 0;
}

static void sx8654_close(struct input_dev *dev)
{
	struct sx8654 *sx8654 = input_get_drvdata(dev);
	struct i2c_client *client = sx8654->client;
	int error;

	disable_irq(client->irq);

	if (!sx8654->data->has_irq_penrelease)
		del_timer_sync(&sx8654->timer);

	/* enable manual mode mode */
	error = i2c_smbus_write_byte(client, sx8654->data->cmd_manual);
	if (error) {
		dev_err(&client->dev, "writing command CMD_MANUAL failed");
		return;
	}

	error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, RATE_MANUAL);
	if (error) {
		dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
		return;
	}
}

static int sx8654_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct sx8654 *sx8654;
	struct input_dev *input;
	int error;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_READ_WORD_DATA))
		return -ENXIO;

	sx8654 = devm_kzalloc(&client->dev, sizeof(*sx8654), GFP_KERNEL);
	if (!sx8654)
		return -ENOMEM;

	sx8654->gpio_reset = devm_gpiod_get_optional(&client->dev, "reset",
						     GPIOD_OUT_HIGH);
	if (IS_ERR(sx8654->gpio_reset)) {
		error = PTR_ERR(sx8654->gpio_reset);
		if (error != -EPROBE_DEFER)
			dev_err(&client->dev, "unable to get reset-gpio: %d\n",
				error);
		return error;
	}
	dev_dbg(&client->dev, "got GPIO reset pin\n");

	sx8654->data = device_get_match_data(&client->dev);
	if (!sx8654->data)
		sx8654->data = (const struct sx865x_data *)id->driver_data;
	if (!sx8654->data) {
		dev_err(&client->dev, "invalid or missing device data\n");
		return -EINVAL;
	}

	if (!sx8654->data->has_irq_penrelease) {
		dev_dbg(&client->dev, "use timer for penrelease\n");
		timer_setup(&sx8654->timer, sx865x_penrelease_timer_handler, 0);
		spin_lock_init(&sx8654->lock);
	}

	input = devm_input_allocate_device(&client->dev);
	if (!input)
		return -ENOMEM;

	input->name = "SX8654 I2C Touchscreen";
	input->id.bustype = BUS_I2C;
	input->dev.parent = &client->dev;
	input->open = sx8654_open;
	input->close = sx8654_close;

	__set_bit(INPUT_PROP_DIRECT, input->propbit);
	input_set_capability(input, EV_KEY, BTN_TOUCH);
	input_set_abs_params(input, ABS_X, 0, MAX_12BIT, 0, 0);
	input_set_abs_params(input, ABS_Y, 0, MAX_12BIT, 0, 0);

	touchscreen_parse_properties(input, false, &sx8654->props);

	sx8654->client = client;
	sx8654->input = input;

	input_set_drvdata(sx8654->input, sx8654);

	error = sx8654_reset(sx8654);
	if (error) {
		dev_err(&client->dev, "reset failed");
		return error;
	}

	error = i2c_smbus_write_byte_data(client, I2C_REG_CHANMASK,
					  sx8654->data->chan_mask);
	if (error) {
		dev_err(&client->dev, "writing to I2C_REG_CHANMASK failed");
		return error;
	}

	if (sx8654->data->has_reg_irqmask) {
		error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
						  IRQ_PENTOUCH_TOUCHCONVDONE |
							IRQ_PENRELEASE);
		if (error) {
			dev_err(&client->dev, "writing I2C_REG_IRQMASK failed");
			return error;
		}
	}

	error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH1,
					  CONDIRQ | RPDNT_100K | FILT_7SA);
	if (error) {
		dev_err(&client->dev, "writing to I2C_REG_TOUCH1 failed");
		return error;
	}

	error = devm_request_threaded_irq(&client->dev, client->irq,
					  NULL, sx8654->data->irqh,
					  IRQF_ONESHOT,
					  client->name, sx8654);
	if (error) {
		dev_err(&client->dev,
			"Failed to enable IRQ %d, error: %d\n",
			client->irq, error);
		return error;
	}

	/* Disable the IRQ, we'll enable it in sx8654_open() */
	disable_irq(client->irq);

	error = input_register_device(sx8654->input);
	if (error)
		return error;

	return 0;
}

static const struct sx865x_data sx8650_data = {
	.cmd_manual		= 0xb0,
	.has_irq_penrelease	= false,
	.has_reg_irqmask	= false,
	.chan_mask		= (CONV_X | CONV_Y),
	.irqh			= sx8650_irq,
};

static const struct sx865x_data sx8654_data = {
	.cmd_manual		= 0xc0,
	.has_irq_penrelease	= true,
	.has_reg_irqmask	= true,
	.chan_mask		= (CONV_X | CONV_Y),
	.irqh			= sx8654_irq,
};

#ifdef CONFIG_OF
static const struct of_device_id sx8654_of_match[] = {
	{
		.compatible = "semtech,sx8650",
		.data = &sx8650_data,
	}, {
		.compatible = "semtech,sx8654",
		.data = &sx8654_data,
	}, {
		.compatible = "semtech,sx8655",
		.data = &sx8654_data,
	}, {
		.compatible = "semtech,sx8656",
		.data = &sx8654_data,
	},
	{ }
};
MODULE_DEVICE_TABLE(of, sx8654_of_match);
#endif

static const struct i2c_device_id sx8654_id_table[] = {
	{ .name = "semtech_sx8650", .driver_data = (long)&sx8650_data },
	{ .name = "semtech_sx8654", .driver_data = (long)&sx8654_data },
	{ .name = "semtech_sx8655", .driver_data = (long)&sx8654_data },
	{ .name = "semtech_sx8656", .driver_data = (long)&sx8654_data },
	{ }
};
MODULE_DEVICE_TABLE(i2c, sx8654_id_table);

static struct i2c_driver sx8654_driver = {
	.driver = {
		.name = "sx8654",
		.of_match_table = of_match_ptr(sx8654_of_match),
	},
	.id_table = sx8654_id_table,
	.probe = sx8654_probe,
};
module_i2c_driver(sx8654_driver);

MODULE_AUTHOR("Sébastien Szymanski <sebastien.szymanski@armadeus.com>");
MODULE_DESCRIPTION("Semtech SX8654 I2C Touchscreen Driver");
MODULE_LICENSE("GPL");