xref: /linux/drivers/input/touchscreen/mms114.c (revision 4263eb6880df8383fff0efb872278a99eb6142c8)
1 // SPDX-License-Identifier: GPL-2.0
2 // Melfas MMS114/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_PACKET_NUM		8
48 
49 /* Touch type */
50 #define MMS114_TYPE_NONE		0
51 #define MMS114_TYPE_TOUCHSCREEN		1
52 #define MMS114_TYPE_TOUCHKEY		2
53 
54 enum mms_type {
55 	TYPE_MMS114	= 114,
56 	TYPE_MMS152	= 152,
57 };
58 
59 struct mms114_data {
60 	struct i2c_client	*client;
61 	struct input_dev	*input_dev;
62 	struct regulator	*core_reg;
63 	struct regulator	*io_reg;
64 	struct touchscreen_properties props;
65 	enum mms_type		type;
66 	unsigned int		contact_threshold;
67 	unsigned int		moving_threshold;
68 
69 	/* Use cache data for mode control register(write only) */
70 	u8			cache_mode_control;
71 };
72 
73 struct mms114_touch {
74 	u8 id:4, reserved_bit4:1, type:2, pressed:1;
75 	u8 x_hi:4, y_hi:4;
76 	u8 x_lo;
77 	u8 y_lo;
78 	u8 width;
79 	u8 strength;
80 	u8 reserved[2];
81 } __packed;
82 
83 static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
84 			     unsigned int len, u8 *val)
85 {
86 	struct i2c_client *client = data->client;
87 	struct i2c_msg xfer[2];
88 	u8 buf = reg & 0xff;
89 	int error;
90 
91 	if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
92 		BUG();
93 
94 	/* Write register */
95 	xfer[0].addr = client->addr;
96 	xfer[0].flags = client->flags & I2C_M_TEN;
97 	xfer[0].len = 1;
98 	xfer[0].buf = &buf;
99 
100 	/* Read data */
101 	xfer[1].addr = client->addr;
102 	xfer[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
103 	xfer[1].len = len;
104 	xfer[1].buf = val;
105 
106 	error = i2c_transfer(client->adapter, xfer, 2);
107 	if (error != 2) {
108 		dev_err(&client->dev,
109 			"%s: i2c transfer failed (%d)\n", __func__, error);
110 		return error < 0 ? error : -EIO;
111 	}
112 	udelay(MMS114_I2C_DELAY);
113 
114 	return 0;
115 }
116 
117 static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
118 {
119 	u8 val;
120 	int error;
121 
122 	if (reg == MMS114_MODE_CONTROL)
123 		return data->cache_mode_control;
124 
125 	error = __mms114_read_reg(data, reg, 1, &val);
126 	return error < 0 ? error : val;
127 }
128 
129 static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
130 			    unsigned int val)
131 {
132 	struct i2c_client *client = data->client;
133 	u8 buf[2];
134 	int error;
135 
136 	buf[0] = reg & 0xff;
137 	buf[1] = val & 0xff;
138 
139 	error = i2c_master_send(client, buf, 2);
140 	if (error != 2) {
141 		dev_err(&client->dev,
142 			"%s: i2c send failed (%d)\n", __func__, error);
143 		return error < 0 ? error : -EIO;
144 	}
145 	udelay(MMS114_I2C_DELAY);
146 
147 	if (reg == MMS114_MODE_CONTROL)
148 		data->cache_mode_control = val;
149 
150 	return 0;
151 }
152 
153 static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
154 {
155 	struct i2c_client *client = data->client;
156 	struct input_dev *input_dev = data->input_dev;
157 	unsigned int id;
158 	unsigned int x;
159 	unsigned int y;
160 
161 	if (touch->id > MMS114_MAX_TOUCH) {
162 		dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
163 		return;
164 	}
165 
166 	if (touch->type != MMS114_TYPE_TOUCHSCREEN) {
167 		dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type);
168 		return;
169 	}
170 
171 	id = touch->id - 1;
172 	x = touch->x_lo | touch->x_hi << 8;
173 	y = touch->y_lo | touch->y_hi << 8;
174 
175 	dev_dbg(&client->dev,
176 		"id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
177 		id, touch->type, touch->pressed,
178 		x, y, touch->width, touch->strength);
179 
180 	input_mt_slot(input_dev, id);
181 	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
182 
183 	if (touch->pressed) {
184 		touchscreen_report_pos(input_dev, &data->props, x, y, true);
185 		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
186 		input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
187 	}
188 }
189 
190 static irqreturn_t mms114_interrupt(int irq, void *dev_id)
191 {
192 	struct mms114_data *data = dev_id;
193 	struct input_dev *input_dev = data->input_dev;
194 	struct mms114_touch touch[MMS114_MAX_TOUCH];
195 	int packet_size;
196 	int touch_size;
197 	int index;
198 	int error;
199 
200 	mutex_lock(&input_dev->mutex);
201 	if (!input_dev->users) {
202 		mutex_unlock(&input_dev->mutex);
203 		goto out;
204 	}
205 	mutex_unlock(&input_dev->mutex);
206 
207 	packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
208 	if (packet_size <= 0)
209 		goto out;
210 
211 	touch_size = packet_size / MMS114_PACKET_NUM;
212 
213 	error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,
214 			(u8 *)touch);
215 	if (error < 0)
216 		goto out;
217 
218 	for (index = 0; index < touch_size; index++)
219 		mms114_process_mt(data, touch + index);
220 
221 	input_mt_report_pointer_emulation(data->input_dev, true);
222 	input_sync(data->input_dev);
223 
224 out:
225 	return IRQ_HANDLED;
226 }
227 
228 static int mms114_set_active(struct mms114_data *data, bool active)
229 {
230 	int val;
231 
232 	val = mms114_read_reg(data, MMS114_MODE_CONTROL);
233 	if (val < 0)
234 		return val;
235 
236 	val &= ~MMS114_OPERATION_MODE_MASK;
237 
238 	/* If active is false, sleep mode */
239 	if (active)
240 		val |= MMS114_ACTIVE;
241 
242 	return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
243 }
244 
245 static int mms114_get_version(struct mms114_data *data)
246 {
247 	struct device *dev = &data->client->dev;
248 	u8 buf[6];
249 	int group;
250 	int error;
251 
252 	switch (data->type) {
253 	case TYPE_MMS152:
254 		error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
255 		if (error)
256 			return error;
257 
258 		group = i2c_smbus_read_byte_data(data->client,
259 						  MMS152_COMPAT_GROUP);
260 		if (group < 0)
261 			return group;
262 
263 		dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x, Compat group: %c\n",
264 			 buf[0], buf[1], buf[2], group);
265 		break;
266 
267 	case TYPE_MMS114:
268 		error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
269 		if (error)
270 			return error;
271 
272 		dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
273 			 buf[0], buf[1], buf[3]);
274 		break;
275 	}
276 
277 	return 0;
278 }
279 
280 static int mms114_setup_regs(struct mms114_data *data)
281 {
282 	const struct touchscreen_properties *props = &data->props;
283 	int val;
284 	int error;
285 
286 	error = mms114_get_version(data);
287 	if (error < 0)
288 		return error;
289 
290 	/* MMS152 has no configuration or power on registers */
291 	if (data->type == TYPE_MMS152)
292 		return 0;
293 
294 	error = mms114_set_active(data, true);
295 	if (error < 0)
296 		return error;
297 
298 	val = (props->max_x >> 8) & 0xf;
299 	val |= ((props->max_y >> 8) & 0xf) << 4;
300 	error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
301 	if (error < 0)
302 		return error;
303 
304 	val = props->max_x & 0xff;
305 	error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
306 	if (error < 0)
307 		return error;
308 
309 	val = props->max_x & 0xff;
310 	error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
311 	if (error < 0)
312 		return error;
313 
314 	if (data->contact_threshold) {
315 		error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
316 				data->contact_threshold);
317 		if (error < 0)
318 			return error;
319 	}
320 
321 	if (data->moving_threshold) {
322 		error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
323 				data->moving_threshold);
324 		if (error < 0)
325 			return error;
326 	}
327 
328 	return 0;
329 }
330 
331 static int mms114_start(struct mms114_data *data)
332 {
333 	struct i2c_client *client = data->client;
334 	int error;
335 
336 	error = regulator_enable(data->core_reg);
337 	if (error) {
338 		dev_err(&client->dev, "Failed to enable avdd: %d\n", error);
339 		return error;
340 	}
341 
342 	error = regulator_enable(data->io_reg);
343 	if (error) {
344 		dev_err(&client->dev, "Failed to enable vdd: %d\n", error);
345 		regulator_disable(data->core_reg);
346 		return error;
347 	}
348 
349 	msleep(MMS114_POWERON_DELAY);
350 
351 	error = mms114_setup_regs(data);
352 	if (error < 0) {
353 		regulator_disable(data->io_reg);
354 		regulator_disable(data->core_reg);
355 		return error;
356 	}
357 
358 	enable_irq(client->irq);
359 
360 	return 0;
361 }
362 
363 static void mms114_stop(struct mms114_data *data)
364 {
365 	struct i2c_client *client = data->client;
366 	int error;
367 
368 	disable_irq(client->irq);
369 
370 	error = regulator_disable(data->io_reg);
371 	if (error)
372 		dev_warn(&client->dev, "Failed to disable vdd: %d\n", error);
373 
374 	error = regulator_disable(data->core_reg);
375 	if (error)
376 		dev_warn(&client->dev, "Failed to disable avdd: %d\n", error);
377 }
378 
379 static int mms114_input_open(struct input_dev *dev)
380 {
381 	struct mms114_data *data = input_get_drvdata(dev);
382 
383 	return mms114_start(data);
384 }
385 
386 static void mms114_input_close(struct input_dev *dev)
387 {
388 	struct mms114_data *data = input_get_drvdata(dev);
389 
390 	mms114_stop(data);
391 }
392 
393 static int mms114_parse_legacy_bindings(struct mms114_data *data)
394 {
395 	struct device *dev = &data->client->dev;
396 	struct touchscreen_properties *props = &data->props;
397 
398 	if (device_property_read_u32(dev, "x-size", &props->max_x)) {
399 		dev_dbg(dev, "failed to get legacy x-size property\n");
400 		return -EINVAL;
401 	}
402 
403 	if (device_property_read_u32(dev, "y-size", &props->max_y)) {
404 		dev_dbg(dev, "failed to get legacy y-size property\n");
405 		return -EINVAL;
406 	}
407 
408 	device_property_read_u32(dev, "contact-threshold",
409 				&data->contact_threshold);
410 	device_property_read_u32(dev, "moving-threshold",
411 				&data->moving_threshold);
412 
413 	if (device_property_read_bool(dev, "x-invert"))
414 		props->invert_x = true;
415 	if (device_property_read_bool(dev, "y-invert"))
416 		props->invert_y = true;
417 
418 	props->swap_x_y = false;
419 
420 	return 0;
421 }
422 
423 static int mms114_probe(struct i2c_client *client,
424 				  const struct i2c_device_id *id)
425 {
426 	struct mms114_data *data;
427 	struct input_dev *input_dev;
428 	const void *match_data;
429 	int error;
430 
431 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
432 		dev_err(&client->dev, "Not supported I2C adapter\n");
433 		return -ENODEV;
434 	}
435 
436 	data = devm_kzalloc(&client->dev, sizeof(struct mms114_data),
437 			    GFP_KERNEL);
438 	input_dev = devm_input_allocate_device(&client->dev);
439 	if (!data || !input_dev) {
440 		dev_err(&client->dev, "Failed to allocate memory\n");
441 		return -ENOMEM;
442 	}
443 
444 	data->client = client;
445 	data->input_dev = input_dev;
446 
447 	match_data = device_get_match_data(&client->dev);
448 	if (!match_data)
449 		return -EINVAL;
450 
451 	data->type = (enum mms_type)match_data;
452 
453 	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
454 	input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
455 	input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
456 	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
457 			     0, MMS114_MAX_AREA, 0, 0);
458 
459 	touchscreen_parse_properties(input_dev, true, &data->props);
460 	if (!data->props.max_x || !data->props.max_y) {
461 		dev_dbg(&client->dev,
462 			"missing X/Y size properties, trying legacy bindings\n");
463 		error = mms114_parse_legacy_bindings(data);
464 		if (error)
465 			return error;
466 
467 		input_set_abs_params(input_dev, ABS_MT_POSITION_X,
468 				     0, data->props.max_x, 0, 0);
469 		input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
470 				     0, data->props.max_y, 0, 0);
471 	}
472 
473 	if (data->type == TYPE_MMS114) {
474 		/*
475 		 * The firmware handles movement and pressure fuzz, so
476 		 * don't duplicate that in software.
477 		 */
478 		data->moving_threshold = input_abs_get_fuzz(input_dev,
479 							    ABS_MT_POSITION_X);
480 		data->contact_threshold = input_abs_get_fuzz(input_dev,
481 							     ABS_MT_PRESSURE);
482 		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_X, 0);
483 		input_abs_set_fuzz(input_dev, ABS_MT_POSITION_Y, 0);
484 		input_abs_set_fuzz(input_dev, ABS_MT_PRESSURE, 0);
485 	}
486 
487 	input_dev->name = devm_kasprintf(&client->dev, GFP_KERNEL,
488 					 "MELFAS MMS%d Touchscreen",
489 					 data->type);
490 	if (!input_dev->name)
491 		return -ENOMEM;
492 
493 	input_dev->id.bustype = BUS_I2C;
494 	input_dev->dev.parent = &client->dev;
495 	input_dev->open = mms114_input_open;
496 	input_dev->close = mms114_input_close;
497 
498 	error = input_mt_init_slots(input_dev, MMS114_MAX_TOUCH,
499 				    INPUT_MT_DIRECT);
500 	if (error)
501 		return error;
502 
503 	input_set_drvdata(input_dev, data);
504 	i2c_set_clientdata(client, data);
505 
506 	data->core_reg = devm_regulator_get(&client->dev, "avdd");
507 	if (IS_ERR(data->core_reg)) {
508 		error = PTR_ERR(data->core_reg);
509 		dev_err(&client->dev,
510 			"Unable to get the Core regulator (%d)\n", error);
511 		return error;
512 	}
513 
514 	data->io_reg = devm_regulator_get(&client->dev, "vdd");
515 	if (IS_ERR(data->io_reg)) {
516 		error = PTR_ERR(data->io_reg);
517 		dev_err(&client->dev,
518 			"Unable to get the IO regulator (%d)\n", error);
519 		return error;
520 	}
521 
522 	error = devm_request_threaded_irq(&client->dev, client->irq,
523 					  NULL, mms114_interrupt, IRQF_ONESHOT,
524 					  dev_name(&client->dev), data);
525 	if (error) {
526 		dev_err(&client->dev, "Failed to register interrupt\n");
527 		return error;
528 	}
529 	disable_irq(client->irq);
530 
531 	error = input_register_device(data->input_dev);
532 	if (error) {
533 		dev_err(&client->dev, "Failed to register input device\n");
534 		return error;
535 	}
536 
537 	return 0;
538 }
539 
540 static int __maybe_unused mms114_suspend(struct device *dev)
541 {
542 	struct i2c_client *client = to_i2c_client(dev);
543 	struct mms114_data *data = i2c_get_clientdata(client);
544 	struct input_dev *input_dev = data->input_dev;
545 	int id;
546 
547 	/* Release all touch */
548 	for (id = 0; id < MMS114_MAX_TOUCH; id++) {
549 		input_mt_slot(input_dev, id);
550 		input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false);
551 	}
552 
553 	input_mt_report_pointer_emulation(input_dev, true);
554 	input_sync(input_dev);
555 
556 	mutex_lock(&input_dev->mutex);
557 	if (input_dev->users)
558 		mms114_stop(data);
559 	mutex_unlock(&input_dev->mutex);
560 
561 	return 0;
562 }
563 
564 static int __maybe_unused mms114_resume(struct device *dev)
565 {
566 	struct i2c_client *client = to_i2c_client(dev);
567 	struct mms114_data *data = i2c_get_clientdata(client);
568 	struct input_dev *input_dev = data->input_dev;
569 	int error;
570 
571 	mutex_lock(&input_dev->mutex);
572 	if (input_dev->users) {
573 		error = mms114_start(data);
574 		if (error < 0) {
575 			mutex_unlock(&input_dev->mutex);
576 			return error;
577 		}
578 	}
579 	mutex_unlock(&input_dev->mutex);
580 
581 	return 0;
582 }
583 
584 static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
585 
586 static const struct i2c_device_id mms114_id[] = {
587 	{ "mms114", 0 },
588 	{ }
589 };
590 MODULE_DEVICE_TABLE(i2c, mms114_id);
591 
592 #ifdef CONFIG_OF
593 static const struct of_device_id mms114_dt_match[] = {
594 	{
595 		.compatible = "melfas,mms114",
596 		.data = (void *)TYPE_MMS114,
597 	}, {
598 		.compatible = "melfas,mms152",
599 		.data = (void *)TYPE_MMS152,
600 	},
601 	{ }
602 };
603 MODULE_DEVICE_TABLE(of, mms114_dt_match);
604 #endif
605 
606 static struct i2c_driver mms114_driver = {
607 	.driver = {
608 		.name	= "mms114",
609 		.pm	= &mms114_pm_ops,
610 		.of_match_table = of_match_ptr(mms114_dt_match),
611 	},
612 	.probe		= mms114_probe,
613 	.id_table	= mms114_id,
614 };
615 
616 module_i2c_driver(mms114_driver);
617 
618 /* Module information */
619 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
620 MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
621 MODULE_LICENSE("GPL v2");
622