1// SPDX-License-Identifier: GPL-2.0
2// Melfas MMS114/MMS136/MMS152 touchscreen device driver
3//
4// Copyright (c) 2012 Samsung Electronics Co., Ltd.
5// Author: Joonyoung Shim <jy0922.shim@samsung.com>
6
7#include <linux/module.h>
8#include <linux/delay.h>
9#include <linux/of.h>
10#include <linux/i2c.h>
11#include <linux/input/mt.h>
12#include <linux/input/touchscreen.h>
13#include <linux/interrupt.h>
14#include <linux/regulator/consumer.h>
15#include <linux/slab.h>
16
17/* Write only registers */
18#define MMS114_MODE_CONTROL		0x01
19#define MMS114_OPERATION_MODE_MASK	0xE
20#define MMS114_ACTIVE			BIT(1)
21
22#define MMS114_XY_RESOLUTION_H		0x02
23#define MMS114_X_RESOLUTION		0x03
24#define MMS114_Y_RESOLUTION		0x04
25#define MMS114_CONTACT_THRESHOLD	0x05
26#define MMS114_MOVING_THRESHOLD		0x06
27
28/* Read only registers */
29#define MMS114_PACKET_SIZE		0x0F
30#define MMS114_INFORMATION		0x10
31#define MMS114_TSP_REV			0xF0
32
33#define MMS152_FW_REV			0xE1
34#define MMS152_COMPAT_GROUP		0xF2
35
36/* Minimum delay time is 50us between stop and start signal of i2c */
37#define MMS114_I2C_DELAY		50
38
39/* 200ms needs after power on */
40#define MMS114_POWERON_DELAY		200
41
42/* Touchscreen absolute values */
43#define MMS114_MAX_AREA			0xff
44
45#define MMS114_MAX_TOUCHKEYS		15
46#define MMS114_MAX_TOUCH		10
47#define MMS114_EVENT_SIZE		8
48#define MMS136_EVENT_SIZE		6
49
50/* Touch type */
51#define MMS114_TYPE_NONE		0
52#define MMS114_TYPE_TOUCHSCREEN		1
53#define MMS114_TYPE_TOUCHKEY		2
54
55enum mms_type {
56	TYPE_MMS114	= 114,
57	TYPE_MMS134S	= 134,
58	TYPE_MMS136	= 136,
59	TYPE_MMS152	= 152,
60	TYPE_MMS345L	= 345,
61};
62
63struct mms114_data {
64	struct i2c_client	*client;
65	struct input_dev	*input_dev;
66	struct regulator	*core_reg;
67	struct regulator	*io_reg;
68	struct touchscreen_properties props;
69	enum mms_type		type;
70	unsigned int		contact_threshold;
71	unsigned int		moving_threshold;
72
73	u32 keycodes[MMS114_MAX_TOUCHKEYS];
74	int num_keycodes;
75
76	/* Use cache data for mode control register(write only) */
77	u8			cache_mode_control;
78};
79
80struct mms114_touch {
81	u8 id:4, reserved_bit4:1, type:2, pressed:1;
82	u8 x_hi:4, y_hi:4;
83	u8 x_lo;
84	u8 y_lo;
85	u8 width;
86	u8 strength;
87	u8 reserved[2];
88} __packed;
89
90static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
91			     unsigned int len, u8 *val)
92{
93	struct i2c_client *client = data->client;
94	struct i2c_msg xfer[2];
95	u8 buf = reg & 0xff;
96	int error;
97
98	if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
99		BUG();
100
101	/* Write register */
102	xfer[0].addr = client->addr;
103	xfer[0].flags = client->flags & I2C_M_TEN;
104	xfer[0].len = 1;
105	xfer[0].buf = &buf;
106
107	/* Read data */
108	xfer[1].addr = client->addr;
109	xfer[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
110	xfer[1].len = len;
111	xfer[1].buf = val;
112
113	error = i2c_transfer(client->adapter, xfer, 2);
114	if (error != 2) {
115		dev_err(&client->dev,
116			"%s: i2c transfer failed (%d)\n", __func__, error);
117		return error < 0 ? error : -EIO;
118	}
119	udelay(MMS114_I2C_DELAY);
120
121	return 0;
122}
123
124static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
125{
126	u8 val;
127	int error;
128
129	if (reg == MMS114_MODE_CONTROL)
130		return data->cache_mode_control;
131
132	error = __mms114_read_reg(data, reg, 1, &val);
133	return error < 0 ? error : val;
134}
135
136static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
137			    unsigned int val)
138{
139	struct i2c_client *client = data->client;
140	u8 buf[2];
141	int error;
142
143	buf[0] = reg & 0xff;
144	buf[1] = val & 0xff;
145
146	error = i2c_master_send(client, buf, 2);
147	if (error != 2) {
148		dev_err(&client->dev,
149			"%s: i2c send failed (%d)\n", __func__, error);
150		return error < 0 ? error : -EIO;
151	}
152	udelay(MMS114_I2C_DELAY);
153
154	if (reg == MMS114_MODE_CONTROL)
155		data->cache_mode_control = val;
156
157	return 0;
158}
159
160static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
161{
162	struct i2c_client *client = data->client;
163	struct input_dev *input_dev = data->input_dev;
164	unsigned int id;
165	unsigned int x;
166	unsigned int y;
167
168	if (touch->id > MMS114_MAX_TOUCH) {
169		dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
170		return;
171	}
172
173	id = touch->id - 1;
174	x = touch->x_lo | touch->x_hi << 8;
175	y = touch->y_lo | touch->y_hi << 8;
176
177	dev_dbg(&client->dev,
178		"id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
179		id, touch->type, touch->pressed,
180		x, y, touch->width, touch->strength);
181
182	input_mt_slot(input_dev, id);
183	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
184
185	if (touch->pressed) {
186		touchscreen_report_pos(input_dev, &data->props, x, y, true);
187		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
188		input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
189	}
190}
191
192static void mms114_process_touchkey(struct mms114_data *data,
193				    struct mms114_touch *touch)
194{
195	struct i2c_client *client = data->client;
196	struct input_dev *input_dev = data->input_dev;
197	unsigned int keycode_id;
198
199	if (touch->id == 0)
200		return;
201
202	if (touch->id > data->num_keycodes) {
203		dev_err(&client->dev, "Wrong touch id for touchkey (%d)\n",
204			touch->id);
205		return;
206	}
207
208	keycode_id = touch->id - 1;
209	dev_dbg(&client->dev, "keycode id: %d, pressed: %d\n", keycode_id,
210		touch->pressed);
211
212	input_report_key(input_dev, data->keycodes[keycode_id], touch->pressed);
213}
214
215static irqreturn_t mms114_interrupt(int irq, void *dev_id)
216{
217	struct mms114_data *data = dev_id;
218	struct i2c_client *client = data->client;
219	struct input_dev *input_dev = data->input_dev;
220	struct mms114_touch touch[MMS114_MAX_TOUCH];
221	int packet_size;
222	int touch_size;
223	int index;
224	int error;
225
226	mutex_lock(&input_dev->mutex);
227	if (!input_device_enabled(input_dev)) {
228		mutex_unlock(&input_dev->mutex);
229		goto out;
230	}
231	mutex_unlock(&input_dev->mutex);
232
233	packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
234	if (packet_size <= 0)
235		goto out;
236
237	/* MMS136 has slightly different event size */
238	if (data->type == TYPE_MMS134S || data->type == TYPE_MMS136)
239		touch_size = packet_size / MMS136_EVENT_SIZE;
240	else
241		touch_size = packet_size / MMS114_EVENT_SIZE;
242
243	error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,
244			(u8 *)touch);
245	if (error < 0)
246		goto out;
247
248	for (index = 0; index < touch_size; index++) {
249		switch (touch[index].type) {
250		case MMS114_TYPE_TOUCHSCREEN:
251			mms114_process_mt(data, touch + index);
252			break;
253
254		case MMS114_TYPE_TOUCHKEY:
255			mms114_process_touchkey(data, touch + index);
256			break;
257
258		default:
259			dev_err(&client->dev, "Wrong touch type (%d)\n",
260				touch[index].type);
261			break;
262		}
263	}
264
265	input_mt_report_pointer_emulation(data->input_dev, true);
266	input_sync(data->input_dev);
267
268out:
269	return IRQ_HANDLED;
270}
271
272static int mms114_set_active(struct mms114_data *data, bool active)
273{
274	int val;
275
276	val = mms114_read_reg(data, MMS114_MODE_CONTROL);
277	if (val < 0)
278		return val;
279
280	val &= ~MMS114_OPERATION_MODE_MASK;
281
282	/* If active is false, sleep mode */
283	if (active)
284		val |= MMS114_ACTIVE;
285
286	return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
287}
288
289static int mms114_get_version(struct mms114_data *data)
290{
291	struct device *dev = &data->client->dev;
292	u8 buf[6];
293	int group;
294	int error;
295
296	switch (data->type) {
297	case TYPE_MMS345L:
298		error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
299		if (error)
300			return error;
301
302		dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x\n",
303			 buf[0], buf[1], buf[2]);
304		break;
305
306	case TYPE_MMS152:
307		error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
308		if (error)
309			return error;
310
311		group = i2c_smbus_read_byte_data(data->client,
312						  MMS152_COMPAT_GROUP);
313		if (group < 0)
314			return group;
315
316		dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x, Compat group: %c\n",
317			 buf[0], buf[1], buf[2], group);
318		break;
319
320	case TYPE_MMS114:
321	case TYPE_MMS134S:
322	case TYPE_MMS136:
323		error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
324		if (error)
325			return error;
326
327		dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
328			 buf[0], buf[1], buf[3]);
329		break;
330	}
331
332	return 0;
333}
334
335static int mms114_setup_regs(struct mms114_data *data)
336{
337	const struct touchscreen_properties *props = &data->props;
338	int val;
339	int error;
340
341	error = mms114_get_version(data);
342	if (error < 0)
343		return error;
344
345	/* MMS114, MMS134S and MMS136 have configuration and power on registers */
346	if (data->type != TYPE_MMS114 && data->type != TYPE_MMS134S &&
347	    data->type != TYPE_MMS136)
348		return 0;
349
350	error = mms114_set_active(data, true);
351	if (error < 0)
352		return error;
353
354	val = (props->max_x >> 8) & 0xf;
355	val |= ((props->max_y >> 8) & 0xf) << 4;
356	error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
357	if (error < 0)
358		return error;
359
360	val = props->max_x & 0xff;
361	error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
362	if (error < 0)
363		return error;
364
365	val = props->max_x & 0xff;
366	error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
367	if (error < 0)
368		return error;
369
370	if (data->contact_threshold) {
371		error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
372				data->contact_threshold);
373		if (error < 0)
374			return error;
375	}
376
377	if (data->moving_threshold) {
378		error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
379				data->moving_threshold);
380		if (error < 0)
381			return error;
382	}
383
384	return 0;
385}
386
387static int mms114_start(struct mms114_data *data)
388{
389	struct i2c_client *client = data->client;
390	int error;
391
392	error = regulator_enable(data->core_reg);
393	if (error) {
394		dev_err(&client->dev, "Failed to enable avdd: %d\n", error);
395		return error;
396	}
397
398	error = regulator_enable(data->io_reg);
399	if (error) {
400		dev_err(&client->dev, "Failed to enable vdd: %d\n", error);
401		regulator_disable(data->core_reg);
402		return error;
403	}
404
405	msleep(MMS114_POWERON_DELAY);
406
407	error = mms114_setup_regs(data);
408	if (error < 0) {
409		regulator_disable(data->io_reg);
410		regulator_disable(data->core_reg);
411		return error;
412	}
413
414	enable_irq(client->irq);
415
416	return 0;
417}
418
419static void mms114_stop(struct mms114_data *data)
420{
421	struct i2c_client *client = data->client;
422	int error;
423
424	disable_irq(client->irq);
425
426	error = regulator_disable(data->io_reg);
427	if (error)
428		dev_warn(&client->dev, "Failed to disable vdd: %d\n", error);
429
430	error = regulator_disable(data->core_reg);
431	if (error)
432		dev_warn(&client->dev, "Failed to disable avdd: %d\n", error);
433}
434
435static int mms114_input_open(struct input_dev *dev)
436{
437	struct mms114_data *data = input_get_drvdata(dev);
438
439	return mms114_start(data);
440}
441
442static void mms114_input_close(struct input_dev *dev)
443{
444	struct mms114_data *data = input_get_drvdata(dev);
445
446	mms114_stop(data);
447}
448
449static int mms114_parse_legacy_bindings(struct mms114_data *data)
450{
451	struct device *dev = &data->client->dev;
452	struct touchscreen_properties *props = &data->props;
453
454	if (device_property_read_u32(dev, "x-size", &props->max_x)) {
455		dev_dbg(dev, "failed to get legacy x-size property\n");
456		return -EINVAL;
457	}
458
459	if (device_property_read_u32(dev, "y-size", &props->max_y)) {
460		dev_dbg(dev, "failed to get legacy y-size property\n");
461		return -EINVAL;
462	}
463
464	device_property_read_u32(dev, "contact-threshold",
465				&data->contact_threshold);
466	device_property_read_u32(dev, "moving-threshold",
467				&data->moving_threshold);
468
469	if (device_property_read_bool(dev, "x-invert"))
470		props->invert_x = true;
471	if (device_property_read_bool(dev, "y-invert"))
472		props->invert_y = true;
473
474	props->swap_x_y = false;
475
476	return 0;
477}
478
479static int mms114_probe(struct i2c_client *client)
480{
481	struct mms114_data *data;
482	struct input_dev *input_dev;
483	const void *match_data;
484	int error;
485	int i;
486
487	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
488		dev_err(&client->dev, "Not supported I2C adapter\n");
489		return -ENODEV;
490	}
491
492	data = devm_kzalloc(&client->dev, sizeof(struct mms114_data),
493			    GFP_KERNEL);
494	input_dev = devm_input_allocate_device(&client->dev);
495	if (!data || !input_dev) {
496		dev_err(&client->dev, "Failed to allocate memory\n");
497		return -ENOMEM;
498	}
499
500	data->client = client;
501	data->input_dev = input_dev;
502
503	match_data = device_get_match_data(&client->dev);
504	if (!match_data)
505		return -EINVAL;
506
507	data->type = (enum mms_type)match_data;
508
509	data->num_keycodes = device_property_count_u32(&client->dev,
510						       "linux,keycodes");
511	if (data->num_keycodes == -EINVAL) {
512		data->num_keycodes = 0;
513	} else if (data->num_keycodes < 0) {
514		dev_err(&client->dev,
515			"Unable to parse linux,keycodes property: %d\n",
516			data->num_keycodes);
517		return data->num_keycodes;
518	} else if (data->num_keycodes > MMS114_MAX_TOUCHKEYS) {
519		dev_warn(&client->dev,
520			"Found %d linux,keycodes but max is %d, ignoring the rest\n",
521			 data->num_keycodes, MMS114_MAX_TOUCHKEYS);
522		data->num_keycodes = MMS114_MAX_TOUCHKEYS;
523	}
524
525	if (data->num_keycodes > 0) {
526		error = device_property_read_u32_array(&client->dev,
527						       "linux,keycodes",
528						       data->keycodes,
529						       data->num_keycodes);
530		if (error) {
531			dev_err(&client->dev,
532				"Unable to read linux,keycodes values: %d\n",
533				error);
534			return error;
535		}
536
537		input_dev->keycode = data->keycodes;
538		input_dev->keycodemax = data->num_keycodes;
539		input_dev->keycodesize = sizeof(data->keycodes[0]);
540		for (i = 0; i < data->num_keycodes; i++)
541			input_set_capability(input_dev,
542					     EV_KEY, data->keycodes[i]);
543	}
544
545	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
546	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
547	input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
548	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
549			     0, MMS114_MAX_AREA, 0, 0);
550
551	touchscreen_parse_properties(input_dev, true, &data->props);
552	if (!data->props.max_x || !data->props.max_y) {
553		dev_dbg(&client->dev,
554			"missing X/Y size properties, trying legacy bindings\n");
555		error = mms114_parse_legacy_bindings(data);
556		if (error)
557			return error;
558
559		input_set_abs_params(input_dev, ABS_MT_POSITION_X,
560				     0, data->props.max_x, 0, 0);
561		input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
562				     0, data->props.max_y, 0, 0);
563	}
564
565	if (data->type == TYPE_MMS114 || data->type == TYPE_MMS134S ||
566	    data->type == TYPE_MMS136) {
567		/*
568		 * The firmware handles movement and pressure fuzz, so
569		 * don't duplicate that in software.
570		 */
571		data->moving_threshold = input_abs_get_fuzz(input_dev,
572							    ABS_MT_POSITION_X);
573		data->contact_threshold = input_abs_get_fuzz(input_dev,
574							     ABS_MT_PRESSURE);
575		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_X, 0);
576		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_Y, 0);
577		input_abs_set_fuzz(input_dev, ABS_MT_PRESSURE, 0);
578	}
579
580	input_dev->name = devm_kasprintf(&client->dev, GFP_KERNEL,
581					 "MELFAS MMS%d Touchscreen",
582					 data->type);
583	if (!input_dev->name)
584		return -ENOMEM;
585
586	input_dev->id.bustype = BUS_I2C;
587	input_dev->dev.parent = &client->dev;
588	input_dev->open = mms114_input_open;
589	input_dev->close = mms114_input_close;
590
591	error = input_mt_init_slots(input_dev, MMS114_MAX_TOUCH,
592				    INPUT_MT_DIRECT);
593	if (error)
594		return error;
595
596	input_set_drvdata(input_dev, data);
597	i2c_set_clientdata(client, data);
598
599	data->core_reg = devm_regulator_get(&client->dev, "avdd");
600	if (IS_ERR(data->core_reg)) {
601		error = PTR_ERR(data->core_reg);
602		dev_err(&client->dev,
603			"Unable to get the Core regulator (%d)\n", error);
604		return error;
605	}
606
607	data->io_reg = devm_regulator_get(&client->dev, "vdd");
608	if (IS_ERR(data->io_reg)) {
609		error = PTR_ERR(data->io_reg);
610		dev_err(&client->dev,
611			"Unable to get the IO regulator (%d)\n", error);
612		return error;
613	}
614
615	error = devm_request_threaded_irq(&client->dev, client->irq,
616					  NULL, mms114_interrupt,
617					  IRQF_ONESHOT | IRQF_NO_AUTOEN,
618					  dev_name(&client->dev), data);
619	if (error) {
620		dev_err(&client->dev, "Failed to register interrupt\n");
621		return error;
622	}
623
624	error = input_register_device(data->input_dev);
625	if (error) {
626		dev_err(&client->dev, "Failed to register input device\n");
627		return error;
628	}
629
630	return 0;
631}
632
633static int mms114_suspend(struct device *dev)
634{
635	struct i2c_client *client = to_i2c_client(dev);
636	struct mms114_data *data = i2c_get_clientdata(client);
637	struct input_dev *input_dev = data->input_dev;
638	int id;
639
640	/* Release all touch */
641	for (id = 0; id < MMS114_MAX_TOUCH; id++) {
642		input_mt_slot(input_dev, id);
643		input_mt_report_slot_inactive(input_dev);
644	}
645
646	input_mt_report_pointer_emulation(input_dev, true);
647	input_sync(input_dev);
648
649	mutex_lock(&input_dev->mutex);
650	if (input_device_enabled(input_dev))
651		mms114_stop(data);
652	mutex_unlock(&input_dev->mutex);
653
654	return 0;
655}
656
657static int mms114_resume(struct device *dev)
658{
659	struct i2c_client *client = to_i2c_client(dev);
660	struct mms114_data *data = i2c_get_clientdata(client);
661	struct input_dev *input_dev = data->input_dev;
662	int error;
663
664	mutex_lock(&input_dev->mutex);
665	if (input_device_enabled(input_dev)) {
666		error = mms114_start(data);
667		if (error < 0) {
668			mutex_unlock(&input_dev->mutex);
669			return error;
670		}
671	}
672	mutex_unlock(&input_dev->mutex);
673
674	return 0;
675}
676
677static DEFINE_SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
678
679static const struct i2c_device_id mms114_id[] = {
680	{ "mms114", 0 },
681	{ }
682};
683MODULE_DEVICE_TABLE(i2c, mms114_id);
684
685#ifdef CONFIG_OF
686static const struct of_device_id mms114_dt_match[] = {
687	{
688		.compatible = "melfas,mms114",
689		.data = (void *)TYPE_MMS114,
690	}, {
691		.compatible = "melfas,mms134s",
692		.data = (void *)TYPE_MMS134S,
693	}, {
694		.compatible = "melfas,mms136",
695		.data = (void *)TYPE_MMS136,
696	}, {
697		.compatible = "melfas,mms152",
698		.data = (void *)TYPE_MMS152,
699	}, {
700		.compatible = "melfas,mms345l",
701		.data = (void *)TYPE_MMS345L,
702	},
703	{ }
704};
705MODULE_DEVICE_TABLE(of, mms114_dt_match);
706#endif
707
708static struct i2c_driver mms114_driver = {
709	.driver = {
710		.name	= "mms114",
711		.pm	= pm_sleep_ptr(&mms114_pm_ops),
712		.of_match_table = of_match_ptr(mms114_dt_match),
713	},
714	.probe		= mms114_probe,
715	.id_table	= mms114_id,
716};
717
718module_i2c_driver(mms114_driver);
719
720/* Module information */
721MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
722MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
723MODULE_LICENSE("GPL v2");
724