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  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/of_device.h>
 11#include <linux/i2c.h>
 12#include <linux/input/mt.h>
 13#include <linux/input/touchscreen.h>
 14#include <linux/interrupt.h>
 15#include <linux/regulator/consumer.h>
 16#include <linux/slab.h>
 17
 18/* Write only registers */
 19#define MMS114_MODE_CONTROL		0x01
 20#define MMS114_OPERATION_MODE_MASK	0xE
 21#define MMS114_ACTIVE			BIT(1)
 22
 23#define MMS114_XY_RESOLUTION_H		0x02
 24#define MMS114_X_RESOLUTION		0x03
 25#define MMS114_Y_RESOLUTION		0x04
 26#define MMS114_CONTACT_THRESHOLD	0x05
 27#define MMS114_MOVING_THRESHOLD		0x06
 28
 29/* Read only registers */
 30#define MMS114_PACKET_SIZE		0x0F
 31#define MMS114_INFORMATION		0x10
 32#define MMS114_TSP_REV			0xF0
 33
 34#define MMS152_FW_REV			0xE1
 35#define MMS152_COMPAT_GROUP		0xF2
 36
 37/* Minimum delay time is 50us between stop and start signal of i2c */
 38#define MMS114_I2C_DELAY		50
 39
 40/* 200ms needs after power on */
 41#define MMS114_POWERON_DELAY		200
 42
 43/* Touchscreen absolute values */
 44#define MMS114_MAX_AREA			0xff
 45
 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_MMS136	= 136,
 58	TYPE_MMS152	= 152,
 59	TYPE_MMS345L	= 345,
 60};
 61
 62struct mms114_data {
 63	struct i2c_client	*client;
 64	struct input_dev	*input_dev;
 65	struct regulator	*core_reg;
 66	struct regulator	*io_reg;
 67	struct touchscreen_properties props;
 68	enum mms_type		type;
 69	unsigned int		contact_threshold;
 70	unsigned int		moving_threshold;
 71
 72	/* Use cache data for mode control register(write only) */
 73	u8			cache_mode_control;
 74};
 75
 76struct mms114_touch {
 77	u8 id:4, reserved_bit4:1, type:2, pressed:1;
 78	u8 x_hi:4, y_hi:4;
 79	u8 x_lo;
 80	u8 y_lo;
 81	u8 width;
 82	u8 strength;
 83	u8 reserved[2];
 84} __packed;
 85
 86static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
 87			     unsigned int len, u8 *val)
 88{
 89	struct i2c_client *client = data->client;
 90	struct i2c_msg xfer[2];
 91	u8 buf = reg & 0xff;
 92	int error;
 93
 94	if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
 95		BUG();
 96
 97	/* Write register */
 98	xfer[0].addr = client->addr;
 99	xfer[0].flags = client->flags & I2C_M_TEN;
100	xfer[0].len = 1;
101	xfer[0].buf = &buf;
102
103	/* Read data */
104	xfer[1].addr = client->addr;
105	xfer[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
106	xfer[1].len = len;
107	xfer[1].buf = val;
108
109	error = i2c_transfer(client->adapter, xfer, 2);
110	if (error != 2) {
111		dev_err(&client->dev,
112			"%s: i2c transfer failed (%d)\n", __func__, error);
113		return error < 0 ? error : -EIO;
114	}
115	udelay(MMS114_I2C_DELAY);
116
117	return 0;
118}
119
120static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
121{
122	u8 val;
123	int error;
124
125	if (reg == MMS114_MODE_CONTROL)
126		return data->cache_mode_control;
127
128	error = __mms114_read_reg(data, reg, 1, &val);
129	return error < 0 ? error : val;
130}
131
132static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
133			    unsigned int val)
134{
135	struct i2c_client *client = data->client;
136	u8 buf[2];
137	int error;
138
139	buf[0] = reg & 0xff;
140	buf[1] = val & 0xff;
141
142	error = i2c_master_send(client, buf, 2);
143	if (error != 2) {
144		dev_err(&client->dev,
145			"%s: i2c send failed (%d)\n", __func__, error);
146		return error < 0 ? error : -EIO;
147	}
148	udelay(MMS114_I2C_DELAY);
149
150	if (reg == MMS114_MODE_CONTROL)
151		data->cache_mode_control = val;
152
153	return 0;
154}
155
156static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
157{
158	struct i2c_client *client = data->client;
159	struct input_dev *input_dev = data->input_dev;
160	unsigned int id;
161	unsigned int x;
162	unsigned int y;
163
164	if (touch->id > MMS114_MAX_TOUCH) {
165		dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
166		return;
167	}
168
169	if (touch->type != MMS114_TYPE_TOUCHSCREEN) {
170		dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type);
171		return;
172	}
173
174	id = touch->id - 1;
175	x = touch->x_lo | touch->x_hi << 8;
176	y = touch->y_lo | touch->y_hi << 8;
177
178	dev_dbg(&client->dev,
179		"id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
180		id, touch->type, touch->pressed,
181		x, y, touch->width, touch->strength);
182
183	input_mt_slot(input_dev, id);
184	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
185
186	if (touch->pressed) {
187		touchscreen_report_pos(input_dev, &data->props, x, y, true);
188		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
189		input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
190	}
191}
192
193static irqreturn_t mms114_interrupt(int irq, void *dev_id)
194{
195	struct mms114_data *data = dev_id;
196	struct input_dev *input_dev = data->input_dev;
197	struct mms114_touch touch[MMS114_MAX_TOUCH];
198	int packet_size;
199	int touch_size;
200	int index;
201	int error;
202
203	mutex_lock(&input_dev->mutex);
204	if (!input_device_enabled(input_dev)) {
205		mutex_unlock(&input_dev->mutex);
206		goto out;
207	}
208	mutex_unlock(&input_dev->mutex);
209
210	packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
211	if (packet_size <= 0)
212		goto out;
213
214	/* MMS136 has slightly different event size */
215	if (data->type == TYPE_MMS136)
216		touch_size = packet_size / MMS136_EVENT_SIZE;
217	else
218		touch_size = packet_size / MMS114_EVENT_SIZE;
219
220	error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,
221			(u8 *)touch);
222	if (error < 0)
223		goto out;
224
225	for (index = 0; index < touch_size; index++)
226		mms114_process_mt(data, touch + index);
227
228	input_mt_report_pointer_emulation(data->input_dev, true);
229	input_sync(data->input_dev);
230
231out:
232	return IRQ_HANDLED;
233}
234
235static int mms114_set_active(struct mms114_data *data, bool active)
236{
237	int val;
238
239	val = mms114_read_reg(data, MMS114_MODE_CONTROL);
240	if (val < 0)
241		return val;
242
243	val &= ~MMS114_OPERATION_MODE_MASK;
244
245	/* If active is false, sleep mode */
246	if (active)
247		val |= MMS114_ACTIVE;
248
249	return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
250}
251
252static int mms114_get_version(struct mms114_data *data)
253{
254	struct device *dev = &data->client->dev;
255	u8 buf[6];
256	int group;
257	int error;
258
259	switch (data->type) {
260	case TYPE_MMS345L:
261		error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
262		if (error)
263			return error;
264
265		dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x\n",
266			 buf[0], buf[1], buf[2]);
267		break;
268
269	case TYPE_MMS152:
270		error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
271		if (error)
272			return error;
273
274		group = i2c_smbus_read_byte_data(data->client,
275						  MMS152_COMPAT_GROUP);
276		if (group < 0)
277			return group;
278
279		dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x, Compat group: %c\n",
280			 buf[0], buf[1], buf[2], group);
281		break;
282
283	case TYPE_MMS114:
284	case TYPE_MMS136:
285		error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
286		if (error)
287			return error;
288
289		dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
290			 buf[0], buf[1], buf[3]);
291		break;
292	}
293
294	return 0;
295}
296
297static int mms114_setup_regs(struct mms114_data *data)
298{
299	const struct touchscreen_properties *props = &data->props;
300	int val;
301	int error;
302
303	error = mms114_get_version(data);
304	if (error < 0)
305		return error;
306
307	/* Only MMS114 and MMS136 have configuration and power on registers */
308	if (data->type != TYPE_MMS114 && data->type != TYPE_MMS136)
309		return 0;
310
311	error = mms114_set_active(data, true);
312	if (error < 0)
313		return error;
314
315	val = (props->max_x >> 8) & 0xf;
316	val |= ((props->max_y >> 8) & 0xf) << 4;
317	error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
318	if (error < 0)
319		return error;
320
321	val = props->max_x & 0xff;
322	error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
323	if (error < 0)
324		return error;
325
326	val = props->max_x & 0xff;
327	error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
328	if (error < 0)
329		return error;
330
331	if (data->contact_threshold) {
332		error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
333				data->contact_threshold);
334		if (error < 0)
335			return error;
336	}
337
338	if (data->moving_threshold) {
339		error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
340				data->moving_threshold);
341		if (error < 0)
342			return error;
343	}
344
345	return 0;
346}
347
348static int mms114_start(struct mms114_data *data)
349{
350	struct i2c_client *client = data->client;
351	int error;
352
353	error = regulator_enable(data->core_reg);
354	if (error) {
355		dev_err(&client->dev, "Failed to enable avdd: %d\n", error);
356		return error;
357	}
358
359	error = regulator_enable(data->io_reg);
360	if (error) {
361		dev_err(&client->dev, "Failed to enable vdd: %d\n", error);
362		regulator_disable(data->core_reg);
363		return error;
364	}
365
366	msleep(MMS114_POWERON_DELAY);
367
368	error = mms114_setup_regs(data);
369	if (error < 0) {
370		regulator_disable(data->io_reg);
371		regulator_disable(data->core_reg);
372		return error;
373	}
374
375	enable_irq(client->irq);
376
377	return 0;
378}
379
380static void mms114_stop(struct mms114_data *data)
381{
382	struct i2c_client *client = data->client;
383	int error;
384
385	disable_irq(client->irq);
386
387	error = regulator_disable(data->io_reg);
388	if (error)
389		dev_warn(&client->dev, "Failed to disable vdd: %d\n", error);
390
391	error = regulator_disable(data->core_reg);
392	if (error)
393		dev_warn(&client->dev, "Failed to disable avdd: %d\n", error);
394}
395
396static int mms114_input_open(struct input_dev *dev)
397{
398	struct mms114_data *data = input_get_drvdata(dev);
399
400	return mms114_start(data);
401}
402
403static void mms114_input_close(struct input_dev *dev)
404{
405	struct mms114_data *data = input_get_drvdata(dev);
406
407	mms114_stop(data);
408}
409
410static int mms114_parse_legacy_bindings(struct mms114_data *data)
411{
412	struct device *dev = &data->client->dev;
413	struct touchscreen_properties *props = &data->props;
414
415	if (device_property_read_u32(dev, "x-size", &props->max_x)) {
416		dev_dbg(dev, "failed to get legacy x-size property\n");
417		return -EINVAL;
418	}
419
420	if (device_property_read_u32(dev, "y-size", &props->max_y)) {
421		dev_dbg(dev, "failed to get legacy y-size property\n");
422		return -EINVAL;
423	}
424
425	device_property_read_u32(dev, "contact-threshold",
426				&data->contact_threshold);
427	device_property_read_u32(dev, "moving-threshold",
428				&data->moving_threshold);
429
430	if (device_property_read_bool(dev, "x-invert"))
431		props->invert_x = true;
432	if (device_property_read_bool(dev, "y-invert"))
433		props->invert_y = true;
434
435	props->swap_x_y = false;
436
437	return 0;
438}
439
440static int mms114_probe(struct i2c_client *client,
441				  const struct i2c_device_id *id)
442{
443	struct mms114_data *data;
444	struct input_dev *input_dev;
445	const void *match_data;
446	int error;
447
448	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
449		dev_err(&client->dev, "Not supported I2C adapter\n");
450		return -ENODEV;
451	}
452
453	data = devm_kzalloc(&client->dev, sizeof(struct mms114_data),
454			    GFP_KERNEL);
455	input_dev = devm_input_allocate_device(&client->dev);
456	if (!data || !input_dev) {
457		dev_err(&client->dev, "Failed to allocate memory\n");
458		return -ENOMEM;
459	}
460
461	data->client = client;
462	data->input_dev = input_dev;
463
464	match_data = device_get_match_data(&client->dev);
465	if (!match_data)
466		return -EINVAL;
467
468	data->type = (enum mms_type)match_data;
469
470	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
471	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
472	input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
473	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
474			     0, MMS114_MAX_AREA, 0, 0);
475
476	touchscreen_parse_properties(input_dev, true, &data->props);
477	if (!data->props.max_x || !data->props.max_y) {
478		dev_dbg(&client->dev,
479			"missing X/Y size properties, trying legacy bindings\n");
480		error = mms114_parse_legacy_bindings(data);
481		if (error)
482			return error;
483
484		input_set_abs_params(input_dev, ABS_MT_POSITION_X,
485				     0, data->props.max_x, 0, 0);
486		input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
487				     0, data->props.max_y, 0, 0);
488	}
489
490	if (data->type == TYPE_MMS114 || data->type == TYPE_MMS136) {
491		/*
492		 * The firmware handles movement and pressure fuzz, so
493		 * don't duplicate that in software.
494		 */
495		data->moving_threshold = input_abs_get_fuzz(input_dev,
496							    ABS_MT_POSITION_X);
497		data->contact_threshold = input_abs_get_fuzz(input_dev,
498							     ABS_MT_PRESSURE);
499		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_X, 0);
500		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_Y, 0);
501		input_abs_set_fuzz(input_dev, ABS_MT_PRESSURE, 0);
502	}
503
504	input_dev->name = devm_kasprintf(&client->dev, GFP_KERNEL,
505					 "MELFAS MMS%d Touchscreen",
506					 data->type);
507	if (!input_dev->name)
508		return -ENOMEM;
509
510	input_dev->id.bustype = BUS_I2C;
511	input_dev->dev.parent = &client->dev;
512	input_dev->open = mms114_input_open;
513	input_dev->close = mms114_input_close;
514
515	error = input_mt_init_slots(input_dev, MMS114_MAX_TOUCH,
516				    INPUT_MT_DIRECT);
517	if (error)
518		return error;
519
520	input_set_drvdata(input_dev, data);
521	i2c_set_clientdata(client, data);
522
523	data->core_reg = devm_regulator_get(&client->dev, "avdd");
524	if (IS_ERR(data->core_reg)) {
525		error = PTR_ERR(data->core_reg);
526		dev_err(&client->dev,
527			"Unable to get the Core regulator (%d)\n", error);
528		return error;
529	}
530
531	data->io_reg = devm_regulator_get(&client->dev, "vdd");
532	if (IS_ERR(data->io_reg)) {
533		error = PTR_ERR(data->io_reg);
534		dev_err(&client->dev,
535			"Unable to get the IO regulator (%d)\n", error);
536		return error;
537	}
538
539	error = devm_request_threaded_irq(&client->dev, client->irq,
540					  NULL, mms114_interrupt,
541					  IRQF_ONESHOT | IRQF_NO_AUTOEN,
542					  dev_name(&client->dev), data);
543	if (error) {
544		dev_err(&client->dev, "Failed to register interrupt\n");
545		return error;
546	}
547
548	error = input_register_device(data->input_dev);
549	if (error) {
550		dev_err(&client->dev, "Failed to register input device\n");
551		return error;
552	}
553
554	return 0;
555}
556
557static int __maybe_unused mms114_suspend(struct device *dev)
558{
559	struct i2c_client *client = to_i2c_client(dev);
560	struct mms114_data *data = i2c_get_clientdata(client);
561	struct input_dev *input_dev = data->input_dev;
562	int id;
563
564	/* Release all touch */
565	for (id = 0; id < MMS114_MAX_TOUCH; id++) {
566		input_mt_slot(input_dev, id);
567		input_mt_report_slot_inactive(input_dev);
568	}
569
570	input_mt_report_pointer_emulation(input_dev, true);
571	input_sync(input_dev);
572
573	mutex_lock(&input_dev->mutex);
574	if (input_device_enabled(input_dev))
575		mms114_stop(data);
576	mutex_unlock(&input_dev->mutex);
577
578	return 0;
579}
580
581static int __maybe_unused mms114_resume(struct device *dev)
582{
583	struct i2c_client *client = to_i2c_client(dev);
584	struct mms114_data *data = i2c_get_clientdata(client);
585	struct input_dev *input_dev = data->input_dev;
586	int error;
587
588	mutex_lock(&input_dev->mutex);
589	if (input_device_enabled(input_dev)) {
590		error = mms114_start(data);
591		if (error < 0) {
592			mutex_unlock(&input_dev->mutex);
593			return error;
594		}
595	}
596	mutex_unlock(&input_dev->mutex);
597
598	return 0;
599}
600
601static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
602
603static const struct i2c_device_id mms114_id[] = {
604	{ "mms114", 0 },
605	{ }
606};
607MODULE_DEVICE_TABLE(i2c, mms114_id);
608
609#ifdef CONFIG_OF
610static const struct of_device_id mms114_dt_match[] = {
611	{
612		.compatible = "melfas,mms114",
613		.data = (void *)TYPE_MMS114,
614	}, {
615		.compatible = "melfas,mms136",
616		.data = (void *)TYPE_MMS136,
617	}, {
618		.compatible = "melfas,mms152",
619		.data = (void *)TYPE_MMS152,
620	}, {
621		.compatible = "melfas,mms345l",
622		.data = (void *)TYPE_MMS345L,
623	},
624	{ }
625};
626MODULE_DEVICE_TABLE(of, mms114_dt_match);
627#endif
628
629static struct i2c_driver mms114_driver = {
630	.driver = {
631		.name	= "mms114",
632		.pm	= &mms114_pm_ops,
633		.of_match_table = of_match_ptr(mms114_dt_match),
634	},
635	.probe		= mms114_probe,
636	.id_table	= mms114_id,
637};
638
639module_i2c_driver(mms114_driver);
640
641/* Module information */
642MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
643MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
644MODULE_LICENSE("GPL v2");