summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/pixcir_i2c_ts.c
blob: fc49c75317d124462bea7c610fcf5741c8fa554c (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
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
/*
 * Driver for Pixcir I2C touchscreen controllers.
 *
 * Copyright (C) 2010-2011 Pixcir, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/pixcir_ts.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>

#define PIXCIR_MAX_SLOTS       5 /* Max fingers supported by driver */

struct pixcir_i2c_ts_data {
	struct i2c_client *client;
	struct input_dev *input;
	const struct pixcir_ts_platform_data *pdata;
	bool running;
	int max_fingers;	/* Max fingers supported in this instance */
};

struct pixcir_touch {
	int x;
	int y;
	int id;
};

struct pixcir_report_data {
	int num_touches;
	struct pixcir_touch touches[PIXCIR_MAX_SLOTS];
};

static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata,
			    struct pixcir_report_data *report)
{
	u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5];
	u8 wrbuf[1] = { 0 };
	u8 *bufptr;
	u8 touch;
	int ret, i;
	int readsize;
	const struct pixcir_i2c_chip_data *chip = &tsdata->pdata->chip;

	memset(report, 0, sizeof(struct pixcir_report_data));

	i = chip->has_hw_ids ? 1 : 0;
	readsize = 2 + tsdata->max_fingers * (4 + i);
	if (readsize > sizeof(rdbuf))
		readsize = sizeof(rdbuf);

	ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf));
	if (ret != sizeof(wrbuf)) {
		dev_err(&tsdata->client->dev,
			"%s: i2c_master_send failed(), ret=%d\n",
			__func__, ret);
		return;
	}

	ret = i2c_master_recv(tsdata->client, rdbuf, readsize);
	if (ret != sizeof(rdbuf)) {
		dev_err(&tsdata->client->dev,
			"%s: i2c_master_recv failed(), ret=%d\n",
			__func__, ret);
		return;
	}

	touch = rdbuf[0] & 0x7;
	if (touch > tsdata->max_fingers)
		touch = tsdata->max_fingers;

	report->num_touches = touch;
	bufptr = &rdbuf[2];

	for (i = 0; i < touch; i++) {
		report->touches[i].x = (bufptr[1] << 8) | bufptr[0];
		report->touches[i].y = (bufptr[3] << 8) | bufptr[2];

		if (chip->has_hw_ids) {
			report->touches[i].id = bufptr[4];
			bufptr = bufptr + 5;
		} else {
			bufptr = bufptr + 4;
		}
	}
}

static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts,
			     struct pixcir_report_data *report)
{
	struct input_mt_pos pos[PIXCIR_MAX_SLOTS];
	int slots[PIXCIR_MAX_SLOTS];
	struct pixcir_touch *touch;
	int n, i, slot;
	struct device *dev = &ts->client->dev;
	const struct pixcir_i2c_chip_data *chip = &ts->pdata->chip;

	n = report->num_touches;
	if (n > PIXCIR_MAX_SLOTS)
		n = PIXCIR_MAX_SLOTS;

	if (!chip->has_hw_ids) {
		for (i = 0; i < n; i++) {
			touch = &report->touches[i];
			pos[i].x = touch->x;
			pos[i].y = touch->y;
		}

		input_mt_assign_slots(ts->input, slots, pos, n);
	}

	for (i = 0; i < n; i++) {
		touch = &report->touches[i];

		if (chip->has_hw_ids) {
			slot = input_mt_get_slot_by_key(ts->input, touch->id);
			if (slot < 0) {
				dev_dbg(dev, "no free slot for id 0x%x\n",
					touch->id);
				continue;
			}
		} else {
			slot = slots[i];
		}

		input_mt_slot(ts->input, slot);
		input_mt_report_slot_state(ts->input,
					   MT_TOOL_FINGER, true);

		input_event(ts->input, EV_ABS, ABS_MT_POSITION_X, touch->x);
		input_event(ts->input, EV_ABS, ABS_MT_POSITION_Y, touch->y);

		dev_dbg(dev, "%d: slot %d, x %d, y %d\n",
			i, slot, touch->x, touch->y);
	}

	input_mt_sync_frame(ts->input);
	input_sync(ts->input);
}

static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
{
	struct pixcir_i2c_ts_data *tsdata = dev_id;
	const struct pixcir_ts_platform_data *pdata = tsdata->pdata;
	struct pixcir_report_data report;

	while (tsdata->running) {
		/* parse packet */
		pixcir_ts_parse(tsdata, &report);

		/* report it */
		pixcir_ts_report(tsdata, &report);

		if (gpio_get_value(pdata->gpio_attb)) {
			if (report.num_touches) {
				/*
				 * Last report with no finger up?
				 * Do it now then.
				 */
				input_mt_sync_frame(tsdata->input);
				input_sync(tsdata->input);
			}
			break;
		}

		msleep(20);
	}

	return IRQ_HANDLED;
}

static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
				 enum pixcir_power_mode mode)
{
	struct device *dev = &ts->client->dev;
	int ret;

	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE);
	if (ret < 0) {
		dev_err(dev, "%s: can't read reg 0x%x : %d\n",
			__func__, PIXCIR_REG_POWER_MODE, ret);
		return ret;
	}

	ret &= ~PIXCIR_POWER_MODE_MASK;
	ret |= mode;

	/* Always AUTO_IDLE */
	ret |= PIXCIR_POWER_ALLOW_IDLE;

	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret);
	if (ret < 0) {
		dev_err(dev, "%s: can't write reg 0x%x : %d\n",
			__func__, PIXCIR_REG_POWER_MODE, ret);
		return ret;
	}

	return 0;
}

/*
 * Set the interrupt mode for the device i.e. ATTB line behaviour
 *
 * @polarity : 1 for active high, 0 for active low.
 */
static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts,
			       enum pixcir_int_mode mode, bool polarity)
{
	struct device *dev = &ts->client->dev;
	int ret;

	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
	if (ret < 0) {
		dev_err(dev, "%s: can't read reg 0x%x : %d\n",
			__func__, PIXCIR_REG_INT_MODE, ret);
		return ret;
	}

	ret &= ~PIXCIR_INT_MODE_MASK;
	ret |= mode;

	if (polarity)
		ret |= PIXCIR_INT_POL_HIGH;
	else
		ret &= ~PIXCIR_INT_POL_HIGH;

	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
	if (ret < 0) {
		dev_err(dev, "%s: can't write reg 0x%x : %d\n",
			__func__, PIXCIR_REG_INT_MODE, ret);
		return ret;
	}

	return 0;
}

/*
 * Enable/disable interrupt generation
 */
static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable)
{
	struct device *dev = &ts->client->dev;
	int ret;

	ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
	if (ret < 0) {
		dev_err(dev, "%s: can't read reg 0x%x : %d\n",
			__func__, PIXCIR_REG_INT_MODE, ret);
		return ret;
	}

	if (enable)
		ret |= PIXCIR_INT_ENABLE;
	else
		ret &= ~PIXCIR_INT_ENABLE;

	ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
	if (ret < 0) {
		dev_err(dev, "%s: can't write reg 0x%x : %d\n",
			__func__, PIXCIR_REG_INT_MODE, ret);
		return ret;
	}

	return 0;
}

static int pixcir_start(struct pixcir_i2c_ts_data *ts)
{
	struct device *dev = &ts->client->dev;
	int error;

	/* LEVEL_TOUCH interrupt with active low polarity */
	error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0);
	if (error) {
		dev_err(dev, "Failed to set interrupt mode: %d\n", error);
		return error;
	}

	ts->running = true;
	mb();	/* Update status before IRQ can fire */

	/* enable interrupt generation */
	error = pixcir_int_enable(ts, true);
	if (error) {
		dev_err(dev, "Failed to enable interrupt generation: %d\n",
			error);
		return error;
	}

	return 0;
}

static int pixcir_stop(struct pixcir_i2c_ts_data *ts)
{
	int error;

	/* Disable interrupt generation */
	error = pixcir_int_enable(ts, false);
	if (error) {
		dev_err(&ts->client->dev,
			"Failed to disable interrupt generation: %d\n",
			error);
		return error;
	}

	/* Exit ISR if running, no more report parsing */
	ts->running = false;
	mb();	/* update status before we synchronize irq */

	/* Wait till running ISR is complete */
	synchronize_irq(ts->client->irq);

	return 0;
}

static int pixcir_input_open(struct input_dev *dev)
{
	struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);

	return pixcir_start(ts);
}

static void pixcir_input_close(struct input_dev *dev)
{
	struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);

	pixcir_stop(ts);
}

#ifdef CONFIG_PM_SLEEP
static int pixcir_i2c_ts_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
	struct input_dev *input = ts->input;
	int ret = 0;

	mutex_lock(&input->mutex);

	if (device_may_wakeup(&client->dev)) {
		if (!input->users) {
			ret = pixcir_start(ts);
			if (ret) {
				dev_err(dev, "Failed to start\n");
				goto unlock;
			}
		}

		enable_irq_wake(client->irq);
	} else if (input->users) {
		ret = pixcir_stop(ts);
	}

unlock:
	mutex_unlock(&input->mutex);

	return ret;
}

static int pixcir_i2c_ts_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
	struct input_dev *input = ts->input;
	int ret = 0;

	mutex_lock(&input->mutex);

	if (device_may_wakeup(&client->dev)) {
		disable_irq_wake(client->irq);

		if (!input->users) {
			ret = pixcir_stop(ts);
			if (ret) {
				dev_err(dev, "Failed to stop\n");
				goto unlock;
			}
		}
	} else if (input->users) {
		ret = pixcir_start(ts);
	}

unlock:
	mutex_unlock(&input->mutex);

	return ret;
}
#endif

static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops,
			 pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume);

#ifdef CONFIG_OF
static const struct of_device_id pixcir_of_match[];

static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev)
{
	struct pixcir_ts_platform_data *pdata;
	struct device_node *np = dev->of_node;
	const struct of_device_id *match;

	match = of_match_device(of_match_ptr(pixcir_of_match), dev);
	if (!match)
		return ERR_PTR(-EINVAL);

	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);

	pdata->chip = *(const struct pixcir_i2c_chip_data *)match->data;

	pdata->gpio_attb = of_get_named_gpio(np, "attb-gpio", 0);
	/* gpio_attb validity is checked in probe */

	if (of_property_read_u32(np, "touchscreen-size-x", &pdata->x_max)) {
		dev_err(dev, "Failed to get touchscreen-size-x property\n");
		return ERR_PTR(-EINVAL);
	}
	pdata->x_max -= 1;

	if (of_property_read_u32(np, "touchscreen-size-y", &pdata->y_max)) {
		dev_err(dev, "Failed to get touchscreen-size-y property\n");
		return ERR_PTR(-EINVAL);
	}
	pdata->y_max -= 1;

	dev_dbg(dev, "%s: x %d, y %d, gpio %d\n", __func__,
		pdata->x_max + 1, pdata->y_max + 1, pdata->gpio_attb);

	return pdata;
}
#else
static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev)
{
	return ERR_PTR(-EINVAL);
}
#endif

static int pixcir_i2c_ts_probe(struct i2c_client *client,
					 const struct i2c_device_id *id)
{
	const struct pixcir_ts_platform_data *pdata =
			dev_get_platdata(&client->dev);
	struct device *dev = &client->dev;
	struct device_node *np = dev->of_node;
	struct pixcir_i2c_ts_data *tsdata;
	struct input_dev *input;
	int error;

	if (np && !pdata) {
		pdata = pixcir_parse_dt(dev);
		if (IS_ERR(pdata))
			return PTR_ERR(pdata);
	}

	if (!pdata) {
		dev_err(&client->dev, "platform data not defined\n");
		return -EINVAL;
	}

	if (!gpio_is_valid(pdata->gpio_attb)) {
		dev_err(dev, "Invalid gpio_attb in pdata\n");
		return -EINVAL;
	}

	if (!pdata->chip.max_fingers) {
		dev_err(dev, "Invalid max_fingers in pdata\n");
		return -EINVAL;
	}

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

	input = devm_input_allocate_device(dev);
	if (!input) {
		dev_err(dev, "Failed to allocate input device\n");
		return -ENOMEM;
	}

	tsdata->client = client;
	tsdata->input = input;
	tsdata->pdata = pdata;

	input->name = client->name;
	input->id.bustype = BUS_I2C;
	input->open = pixcir_input_open;
	input->close = pixcir_input_close;
	input->dev.parent = &client->dev;

	__set_bit(EV_KEY, input->evbit);
	__set_bit(EV_ABS, input->evbit);
	__set_bit(BTN_TOUCH, input->keybit);
	input_set_abs_params(input, ABS_X, 0, pdata->x_max, 0, 0);
	input_set_abs_params(input, ABS_Y, 0, pdata->y_max, 0, 0);
	input_set_abs_params(input, ABS_MT_POSITION_X, 0, pdata->x_max, 0, 0);
	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, pdata->y_max, 0, 0);

	tsdata->max_fingers = tsdata->pdata->chip.max_fingers;
	if (tsdata->max_fingers > PIXCIR_MAX_SLOTS) {
		tsdata->max_fingers = PIXCIR_MAX_SLOTS;
		dev_info(dev, "Limiting maximum fingers to %d\n",
			 tsdata->max_fingers);
	}

	error = input_mt_init_slots(input, tsdata->max_fingers,
				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
	if (error) {
		dev_err(dev, "Error initializing Multi-Touch slots\n");
		return error;
	}

	input_set_drvdata(input, tsdata);

	error = devm_gpio_request_one(dev, pdata->gpio_attb,
				      GPIOF_DIR_IN, "pixcir_i2c_attb");
	if (error) {
		dev_err(dev, "Failed to request ATTB gpio\n");
		return error;
	}

	error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr,
					  IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
					  client->name, tsdata);
	if (error) {
		dev_err(dev, "failed to request irq %d\n", client->irq);
		return error;
	}

	/* Always be in IDLE mode to save power, device supports auto wake */
	error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE);
	if (error) {
		dev_err(dev, "Failed to set IDLE mode\n");
		return error;
	}

	/* Stop device till opened */
	error = pixcir_stop(tsdata);
	if (error)
		return error;

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

	i2c_set_clientdata(client, tsdata);
	device_init_wakeup(&client->dev, 1);

	return 0;
}

static int pixcir_i2c_ts_remove(struct i2c_client *client)
{
	device_init_wakeup(&client->dev, 0);

	return 0;
}

static const struct i2c_device_id pixcir_i2c_ts_id[] = {
	{ "pixcir_ts", 0 },
	{ "pixcir_tangoc", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);

#ifdef CONFIG_OF
static const struct pixcir_i2c_chip_data pixcir_ts_data = {
	.max_fingers = 2,
	/* no hw id support */
};

static const struct pixcir_i2c_chip_data pixcir_tangoc_data = {
	.max_fingers = 5,
	.has_hw_ids = true,
};

static const struct of_device_id pixcir_of_match[] = {
	{ .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data },
	{ .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data },
	{ }
};
MODULE_DEVICE_TABLE(of, pixcir_of_match);
#endif

static struct i2c_driver pixcir_i2c_ts_driver = {
	.driver = {
		.owner	= THIS_MODULE,
		.name	= "pixcir_ts",
		.pm	= &pixcir_dev_pm_ops,
		.of_match_table = of_match_ptr(pixcir_of_match),
	},
	.probe		= pixcir_i2c_ts_probe,
	.remove		= pixcir_i2c_ts_remove,
	.id_table	= pixcir_i2c_ts_id,
};

module_i2c_driver(pixcir_i2c_ts_driver);

MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>");
MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud