1// SPDX-License-Identifier: GPL-2.0
2// STMicroelectronics FTS Touchscreen device driver
3//
4// Copyright (c) 2017 Samsung Electronics Co., Ltd.
5// Copyright (c) 2017 Andi Shyti <andi@etezian.org>
6
7#include <linux/delay.h>
8#include <linux/i2c.h>
9#include <linux/input/mt.h>
10#include <linux/input/touchscreen.h>
11#include <linux/interrupt.h>
12#include <linux/irq.h>
13#include <linux/leds.h>
14#include <linux/module.h>
15#include <linux/pm_runtime.h>
16#include <linux/regulator/consumer.h>
17
18/* I2C commands */
19#define STMFTS_READ_INFO			0x80
20#define STMFTS_READ_STATUS			0x84
21#define STMFTS_READ_ONE_EVENT			0x85
22#define STMFTS_READ_ALL_EVENT			0x86
23#define STMFTS_LATEST_EVENT			0x87
24#define STMFTS_SLEEP_IN				0x90
25#define STMFTS_SLEEP_OUT			0x91
26#define STMFTS_MS_MT_SENSE_OFF			0x92
27#define STMFTS_MS_MT_SENSE_ON			0x93
28#define STMFTS_SS_HOVER_SENSE_OFF		0x94
29#define STMFTS_SS_HOVER_SENSE_ON		0x95
30#define STMFTS_MS_KEY_SENSE_OFF			0x9a
31#define STMFTS_MS_KEY_SENSE_ON			0x9b
32#define STMFTS_SYSTEM_RESET			0xa0
33#define STMFTS_CLEAR_EVENT_STACK		0xa1
34#define STMFTS_FULL_FORCE_CALIBRATION		0xa2
35#define STMFTS_MS_CX_TUNING			0xa3
36#define STMFTS_SS_CX_TUNING			0xa4
37
38/* events */
39#define STMFTS_EV_NO_EVENT			0x00
40#define STMFTS_EV_MULTI_TOUCH_DETECTED		0x02
41#define STMFTS_EV_MULTI_TOUCH_ENTER		0x03
42#define STMFTS_EV_MULTI_TOUCH_LEAVE		0x04
43#define STMFTS_EV_MULTI_TOUCH_MOTION		0x05
44#define STMFTS_EV_HOVER_ENTER			0x07
45#define STMFTS_EV_HOVER_LEAVE			0x08
46#define STMFTS_EV_HOVER_MOTION			0x09
47#define STMFTS_EV_KEY_STATUS			0x0e
48#define STMFTS_EV_ERROR				0x0f
49#define STMFTS_EV_CONTROLLER_READY		0x10
50#define STMFTS_EV_SLEEP_OUT_CONTROLLER_READY	0x11
51#define STMFTS_EV_STATUS			0x16
52#define STMFTS_EV_DEBUG				0xdb
53
54/* multi touch related event masks */
55#define STMFTS_MASK_EVENT_ID			0x0f
56#define STMFTS_MASK_TOUCH_ID			0xf0
57#define STMFTS_MASK_LEFT_EVENT			0x0f
58#define STMFTS_MASK_X_MSB			0x0f
59#define STMFTS_MASK_Y_LSB			0xf0
60
61/* key related event masks */
62#define STMFTS_MASK_KEY_NO_TOUCH		0x00
63#define STMFTS_MASK_KEY_MENU			0x01
64#define STMFTS_MASK_KEY_BACK			0x02
65
66#define STMFTS_EVENT_SIZE	8
67#define STMFTS_STACK_DEPTH	32
68#define STMFTS_DATA_MAX_SIZE	(STMFTS_EVENT_SIZE * STMFTS_STACK_DEPTH)
69#define STMFTS_MAX_FINGERS	10
70#define STMFTS_DEV_NAME		"stmfts"
71
72enum stmfts_regulators {
73	STMFTS_REGULATOR_VDD,
74	STMFTS_REGULATOR_AVDD,
75};
76
77struct stmfts_data {
78	struct i2c_client *client;
79	struct input_dev *input;
80	struct led_classdev led_cdev;
81	struct mutex mutex;
82
83	struct touchscreen_properties prop;
84
85	struct regulator_bulk_data regulators[2];
86
87	/*
88	 * Presence of ledvdd will be used also to check
89	 * whether the LED is supported.
90	 */
91	struct regulator *ledvdd;
92
93	u16 chip_id;
94	u8 chip_ver;
95	u16 fw_ver;
96	u8 config_id;
97	u8 config_ver;
98
99	u8 data[STMFTS_DATA_MAX_SIZE];
100
101	struct completion cmd_done;
102
103	bool use_key;
104	bool led_status;
105	bool hover_enabled;
106	bool running;
107};
108
109static int stmfts_brightness_set(struct led_classdev *led_cdev,
110					enum led_brightness value)
111{
112	struct stmfts_data *sdata = container_of(led_cdev,
113					struct stmfts_data, led_cdev);
114	int err;
115
116	if (value != sdata->led_status && sdata->ledvdd) {
117		if (!value) {
118			regulator_disable(sdata->ledvdd);
119		} else {
120			err = regulator_enable(sdata->ledvdd);
121			if (err) {
122				dev_warn(&sdata->client->dev,
123					 "failed to disable ledvdd regulator: %d\n",
124					 err);
125				return err;
126			}
127		}
128		sdata->led_status = value;
129	}
130
131	return 0;
132}
133
134static enum led_brightness stmfts_brightness_get(struct led_classdev *led_cdev)
135{
136	struct stmfts_data *sdata = container_of(led_cdev,
137						struct stmfts_data, led_cdev);
138
139	return !!regulator_is_enabled(sdata->ledvdd);
140}
141
142/*
143 * We can't simply use i2c_smbus_read_i2c_block_data because we
144 * need to read more than 255 bytes (
145 */
146static int stmfts_read_events(struct stmfts_data *sdata)
147{
148	u8 cmd = STMFTS_READ_ALL_EVENT;
149	struct i2c_msg msgs[2] = {
150		{
151			.addr	= sdata->client->addr,
152			.len	= 1,
153			.buf	= &cmd,
154		},
155		{
156			.addr	= sdata->client->addr,
157			.flags	= I2C_M_RD,
158			.len	= STMFTS_DATA_MAX_SIZE,
159			.buf	= sdata->data,
160		},
161	};
162	int ret;
163
164	ret = i2c_transfer(sdata->client->adapter, msgs, ARRAY_SIZE(msgs));
165	if (ret < 0)
166		return ret;
167
168	return ret == ARRAY_SIZE(msgs) ? 0 : -EIO;
169}
170
171static void stmfts_report_contact_event(struct stmfts_data *sdata,
172					const u8 event[])
173{
174	u8 slot_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;
175	u16 x = event[1] | ((event[2] & STMFTS_MASK_X_MSB) << 8);
176	u16 y = (event[2] >> 4) | (event[3] << 4);
177	u8 maj = event[4];
178	u8 min = event[5];
179	u8 orientation = event[6];
180	u8 area = event[7];
181
182	input_mt_slot(sdata->input, slot_id);
183
184	input_mt_report_slot_state(sdata->input, MT_TOOL_FINGER, true);
185	input_report_abs(sdata->input, ABS_MT_POSITION_X, x);
186	input_report_abs(sdata->input, ABS_MT_POSITION_Y, y);
187	input_report_abs(sdata->input, ABS_MT_TOUCH_MAJOR, maj);
188	input_report_abs(sdata->input, ABS_MT_TOUCH_MINOR, min);
189	input_report_abs(sdata->input, ABS_MT_PRESSURE, area);
190	input_report_abs(sdata->input, ABS_MT_ORIENTATION, orientation);
191
192	input_sync(sdata->input);
193}
194
195static void stmfts_report_contact_release(struct stmfts_data *sdata,
196					  const u8 event[])
197{
198	u8 slot_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;
199
200	input_mt_slot(sdata->input, slot_id);
201	input_mt_report_slot_inactive(sdata->input);
202
203	input_sync(sdata->input);
204}
205
206static void stmfts_report_hover_event(struct stmfts_data *sdata,
207				      const u8 event[])
208{
209	u16 x = (event[2] << 4) | (event[4] >> 4);
210	u16 y = (event[3] << 4) | (event[4] & STMFTS_MASK_Y_LSB);
211	u8 z = event[5];
212
213	input_report_abs(sdata->input, ABS_X, x);
214	input_report_abs(sdata->input, ABS_Y, y);
215	input_report_abs(sdata->input, ABS_DISTANCE, z);
216
217	input_sync(sdata->input);
218}
219
220static void stmfts_report_key_event(struct stmfts_data *sdata, const u8 event[])
221{
222	switch (event[2]) {
223	case 0:
224		input_report_key(sdata->input, KEY_BACK, 0);
225		input_report_key(sdata->input, KEY_MENU, 0);
226		break;
227
228	case STMFTS_MASK_KEY_BACK:
229		input_report_key(sdata->input, KEY_BACK, 1);
230		break;
231
232	case STMFTS_MASK_KEY_MENU:
233		input_report_key(sdata->input, KEY_MENU, 1);
234		break;
235
236	default:
237		dev_warn(&sdata->client->dev,
238			 "unknown key event: %#02x\n", event[2]);
239		break;
240	}
241
242	input_sync(sdata->input);
243}
244
245static void stmfts_parse_events(struct stmfts_data *sdata)
246{
247	int i;
248
249	for (i = 0; i < STMFTS_STACK_DEPTH; i++) {
250		u8 *event = &sdata->data[i * STMFTS_EVENT_SIZE];
251
252		switch (event[0]) {
253
254		case STMFTS_EV_CONTROLLER_READY:
255		case STMFTS_EV_SLEEP_OUT_CONTROLLER_READY:
256		case STMFTS_EV_STATUS:
257			complete(&sdata->cmd_done);
258			fallthrough;
259
260		case STMFTS_EV_NO_EVENT:
261		case STMFTS_EV_DEBUG:
262			return;
263		}
264
265		switch (event[0] & STMFTS_MASK_EVENT_ID) {
266
267		case STMFTS_EV_MULTI_TOUCH_ENTER:
268		case STMFTS_EV_MULTI_TOUCH_MOTION:
269			stmfts_report_contact_event(sdata, event);
270			break;
271
272		case STMFTS_EV_MULTI_TOUCH_LEAVE:
273			stmfts_report_contact_release(sdata, event);
274			break;
275
276		case STMFTS_EV_HOVER_ENTER:
277		case STMFTS_EV_HOVER_LEAVE:
278		case STMFTS_EV_HOVER_MOTION:
279			stmfts_report_hover_event(sdata, event);
280			break;
281
282		case STMFTS_EV_KEY_STATUS:
283			stmfts_report_key_event(sdata, event);
284			break;
285
286		case STMFTS_EV_ERROR:
287			dev_warn(&sdata->client->dev,
288					"error code: 0x%x%x%x%x%x%x",
289					event[6], event[5], event[4],
290					event[3], event[2], event[1]);
291			break;
292
293		default:
294			dev_err(&sdata->client->dev,
295				"unknown event %#02x\n", event[0]);
296		}
297	}
298}
299
300static irqreturn_t stmfts_irq_handler(int irq, void *dev)
301{
302	struct stmfts_data *sdata = dev;
303	int err;
304
305	mutex_lock(&sdata->mutex);
306
307	err = stmfts_read_events(sdata);
308	if (unlikely(err))
309		dev_err(&sdata->client->dev,
310			"failed to read events: %d\n", err);
311	else
312		stmfts_parse_events(sdata);
313
314	mutex_unlock(&sdata->mutex);
315	return IRQ_HANDLED;
316}
317
318static int stmfts_command(struct stmfts_data *sdata, const u8 cmd)
319{
320	int err;
321
322	reinit_completion(&sdata->cmd_done);
323
324	err = i2c_smbus_write_byte(sdata->client, cmd);
325	if (err)
326		return err;
327
328	if (!wait_for_completion_timeout(&sdata->cmd_done,
329					 msecs_to_jiffies(1000)))
330		return -ETIMEDOUT;
331
332	return 0;
333}
334
335static int stmfts_input_open(struct input_dev *dev)
336{
337	struct stmfts_data *sdata = input_get_drvdata(dev);
338	int err;
339
340	err = pm_runtime_resume_and_get(&sdata->client->dev);
341	if (err)
342		return err;
343
344	err = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_ON);
345	if (err) {
346		pm_runtime_put_sync(&sdata->client->dev);
347		return err;
348	}
349
350	mutex_lock(&sdata->mutex);
351	sdata->running = true;
352
353	if (sdata->hover_enabled) {
354		err = i2c_smbus_write_byte(sdata->client,
355					   STMFTS_SS_HOVER_SENSE_ON);
356		if (err)
357			dev_warn(&sdata->client->dev,
358				 "failed to enable hover\n");
359	}
360	mutex_unlock(&sdata->mutex);
361
362	if (sdata->use_key) {
363		err = i2c_smbus_write_byte(sdata->client,
364					   STMFTS_MS_KEY_SENSE_ON);
365		if (err)
366			/* I can still use only the touch screen */
367			dev_warn(&sdata->client->dev,
368				 "failed to enable touchkey\n");
369	}
370
371	return 0;
372}
373
374static void stmfts_input_close(struct input_dev *dev)
375{
376	struct stmfts_data *sdata = input_get_drvdata(dev);
377	int err;
378
379	err = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_OFF);
380	if (err)
381		dev_warn(&sdata->client->dev,
382			 "failed to disable touchscreen: %d\n", err);
383
384	mutex_lock(&sdata->mutex);
385
386	sdata->running = false;
387
388	if (sdata->hover_enabled) {
389		err = i2c_smbus_write_byte(sdata->client,
390					   STMFTS_SS_HOVER_SENSE_OFF);
391		if (err)
392			dev_warn(&sdata->client->dev,
393				 "failed to disable hover: %d\n", err);
394	}
395	mutex_unlock(&sdata->mutex);
396
397	if (sdata->use_key) {
398		err = i2c_smbus_write_byte(sdata->client,
399					   STMFTS_MS_KEY_SENSE_OFF);
400		if (err)
401			dev_warn(&sdata->client->dev,
402				 "failed to disable touchkey: %d\n", err);
403	}
404
405	pm_runtime_put_sync(&sdata->client->dev);
406}
407
408static ssize_t stmfts_sysfs_chip_id(struct device *dev,
409				struct device_attribute *attr, char *buf)
410{
411	struct stmfts_data *sdata = dev_get_drvdata(dev);
412
413	return sprintf(buf, "%#x\n", sdata->chip_id);
414}
415
416static ssize_t stmfts_sysfs_chip_version(struct device *dev,
417				struct device_attribute *attr, char *buf)
418{
419	struct stmfts_data *sdata = dev_get_drvdata(dev);
420
421	return sprintf(buf, "%u\n", sdata->chip_ver);
422}
423
424static ssize_t stmfts_sysfs_fw_ver(struct device *dev,
425				struct device_attribute *attr, char *buf)
426{
427	struct stmfts_data *sdata = dev_get_drvdata(dev);
428
429	return sprintf(buf, "%u\n", sdata->fw_ver);
430}
431
432static ssize_t stmfts_sysfs_config_id(struct device *dev,
433				struct device_attribute *attr, char *buf)
434{
435	struct stmfts_data *sdata = dev_get_drvdata(dev);
436
437	return sprintf(buf, "%#x\n", sdata->config_id);
438}
439
440static ssize_t stmfts_sysfs_config_version(struct device *dev,
441				struct device_attribute *attr, char *buf)
442{
443	struct stmfts_data *sdata = dev_get_drvdata(dev);
444
445	return sprintf(buf, "%u\n", sdata->config_ver);
446}
447
448static ssize_t stmfts_sysfs_read_status(struct device *dev,
449				struct device_attribute *attr, char *buf)
450{
451	struct stmfts_data *sdata = dev_get_drvdata(dev);
452	u8 status[4];
453	int err;
454
455	err = i2c_smbus_read_i2c_block_data(sdata->client, STMFTS_READ_STATUS,
456					    sizeof(status), status);
457	if (err)
458		return err;
459
460	return sprintf(buf, "%#02x\n", status[0]);
461}
462
463static ssize_t stmfts_sysfs_hover_enable_read(struct device *dev,
464				struct device_attribute *attr, char *buf)
465{
466	struct stmfts_data *sdata = dev_get_drvdata(dev);
467
468	return sprintf(buf, "%u\n", sdata->hover_enabled);
469}
470
471static ssize_t stmfts_sysfs_hover_enable_write(struct device *dev,
472				struct device_attribute *attr,
473				const char *buf, size_t len)
474{
475	struct stmfts_data *sdata = dev_get_drvdata(dev);
476	unsigned long value;
477	int err = 0;
478
479	if (kstrtoul(buf, 0, &value))
480		return -EINVAL;
481
482	mutex_lock(&sdata->mutex);
483
484	if (value && sdata->hover_enabled)
485		goto out;
486
487	if (sdata->running)
488		err = i2c_smbus_write_byte(sdata->client,
489					   value ? STMFTS_SS_HOVER_SENSE_ON :
490						   STMFTS_SS_HOVER_SENSE_OFF);
491
492	if (!err)
493		sdata->hover_enabled = !!value;
494
495out:
496	mutex_unlock(&sdata->mutex);
497
498	return len;
499}
500
501static DEVICE_ATTR(chip_id, 0444, stmfts_sysfs_chip_id, NULL);
502static DEVICE_ATTR(chip_version, 0444, stmfts_sysfs_chip_version, NULL);
503static DEVICE_ATTR(fw_ver, 0444, stmfts_sysfs_fw_ver, NULL);
504static DEVICE_ATTR(config_id, 0444, stmfts_sysfs_config_id, NULL);
505static DEVICE_ATTR(config_version, 0444, stmfts_sysfs_config_version, NULL);
506static DEVICE_ATTR(status, 0444, stmfts_sysfs_read_status, NULL);
507static DEVICE_ATTR(hover_enable, 0644, stmfts_sysfs_hover_enable_read,
508					stmfts_sysfs_hover_enable_write);
509
510static struct attribute *stmfts_sysfs_attrs[] = {
511	&dev_attr_chip_id.attr,
512	&dev_attr_chip_version.attr,
513	&dev_attr_fw_ver.attr,
514	&dev_attr_config_id.attr,
515	&dev_attr_config_version.attr,
516	&dev_attr_status.attr,
517	&dev_attr_hover_enable.attr,
518	NULL
519};
520ATTRIBUTE_GROUPS(stmfts_sysfs);
521
522static int stmfts_power_on(struct stmfts_data *sdata)
523{
524	int err;
525	u8 reg[8];
526
527	err = regulator_bulk_enable(ARRAY_SIZE(sdata->regulators),
528				    sdata->regulators);
529	if (err)
530		return err;
531
532	/*
533	 * The datasheet does not specify the power on time, but considering
534	 * that the reset time is < 10ms, I sleep 20ms to be sure
535	 */
536	msleep(20);
537
538	err = i2c_smbus_read_i2c_block_data(sdata->client, STMFTS_READ_INFO,
539					    sizeof(reg), reg);
540	if (err < 0)
541		return err;
542	if (err != sizeof(reg))
543		return -EIO;
544
545	sdata->chip_id = be16_to_cpup((__be16 *)&reg[6]);
546	sdata->chip_ver = reg[0];
547	sdata->fw_ver = be16_to_cpup((__be16 *)&reg[2]);
548	sdata->config_id = reg[4];
549	sdata->config_ver = reg[5];
550
551	enable_irq(sdata->client->irq);
552
553	msleep(50);
554
555	err = stmfts_command(sdata, STMFTS_SYSTEM_RESET);
556	if (err)
557		return err;
558
559	err = stmfts_command(sdata, STMFTS_SLEEP_OUT);
560	if (err)
561		return err;
562
563	/* optional tuning */
564	err = stmfts_command(sdata, STMFTS_MS_CX_TUNING);
565	if (err)
566		dev_warn(&sdata->client->dev,
567			 "failed to perform mutual auto tune: %d\n", err);
568
569	/* optional tuning */
570	err = stmfts_command(sdata, STMFTS_SS_CX_TUNING);
571	if (err)
572		dev_warn(&sdata->client->dev,
573			 "failed to perform self auto tune: %d\n", err);
574
575	err = stmfts_command(sdata, STMFTS_FULL_FORCE_CALIBRATION);
576	if (err)
577		return err;
578
579	/*
580	 * At this point no one is using the touchscreen
581	 * and I don't really care about the return value
582	 */
583	(void) i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);
584
585	return 0;
586}
587
588static void stmfts_power_off(void *data)
589{
590	struct stmfts_data *sdata = data;
591
592	disable_irq(sdata->client->irq);
593	regulator_bulk_disable(ARRAY_SIZE(sdata->regulators),
594						sdata->regulators);
595}
596
597/* This function is void because I don't want to prevent using the touch key
598 * only because the LEDs don't get registered
599 */
600static int stmfts_enable_led(struct stmfts_data *sdata)
601{
602	int err;
603
604	/* get the regulator for powering the leds on */
605	sdata->ledvdd = devm_regulator_get(&sdata->client->dev, "ledvdd");
606	if (IS_ERR(sdata->ledvdd))
607		return PTR_ERR(sdata->ledvdd);
608
609	sdata->led_cdev.name = STMFTS_DEV_NAME;
610	sdata->led_cdev.max_brightness = LED_ON;
611	sdata->led_cdev.brightness = LED_OFF;
612	sdata->led_cdev.brightness_set_blocking = stmfts_brightness_set;
613	sdata->led_cdev.brightness_get = stmfts_brightness_get;
614
615	err = devm_led_classdev_register(&sdata->client->dev, &sdata->led_cdev);
616	if (err) {
617		devm_regulator_put(sdata->ledvdd);
618		return err;
619	}
620
621	return 0;
622}
623
624static int stmfts_probe(struct i2c_client *client)
625{
626	int err;
627	struct stmfts_data *sdata;
628
629	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
630						I2C_FUNC_SMBUS_BYTE_DATA |
631						I2C_FUNC_SMBUS_I2C_BLOCK))
632		return -ENODEV;
633
634	sdata = devm_kzalloc(&client->dev, sizeof(*sdata), GFP_KERNEL);
635	if (!sdata)
636		return -ENOMEM;
637
638	i2c_set_clientdata(client, sdata);
639
640	sdata->client = client;
641	mutex_init(&sdata->mutex);
642	init_completion(&sdata->cmd_done);
643
644	sdata->regulators[STMFTS_REGULATOR_VDD].supply = "vdd";
645	sdata->regulators[STMFTS_REGULATOR_AVDD].supply = "avdd";
646	err = devm_regulator_bulk_get(&client->dev,
647				      ARRAY_SIZE(sdata->regulators),
648				      sdata->regulators);
649	if (err)
650		return err;
651
652	sdata->input = devm_input_allocate_device(&client->dev);
653	if (!sdata->input)
654		return -ENOMEM;
655
656	sdata->input->name = STMFTS_DEV_NAME;
657	sdata->input->id.bustype = BUS_I2C;
658	sdata->input->open = stmfts_input_open;
659	sdata->input->close = stmfts_input_close;
660
661	input_set_capability(sdata->input, EV_ABS, ABS_MT_POSITION_X);
662	input_set_capability(sdata->input, EV_ABS, ABS_MT_POSITION_Y);
663	touchscreen_parse_properties(sdata->input, true, &sdata->prop);
664
665	input_set_abs_params(sdata->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
666	input_set_abs_params(sdata->input, ABS_MT_TOUCH_MINOR, 0, 255, 0, 0);
667	input_set_abs_params(sdata->input, ABS_MT_ORIENTATION, 0, 255, 0, 0);
668	input_set_abs_params(sdata->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
669	input_set_abs_params(sdata->input, ABS_DISTANCE, 0, 255, 0, 0);
670
671	sdata->use_key = device_property_read_bool(&client->dev,
672						   "touch-key-connected");
673	if (sdata->use_key) {
674		input_set_capability(sdata->input, EV_KEY, KEY_MENU);
675		input_set_capability(sdata->input, EV_KEY, KEY_BACK);
676	}
677
678	err = input_mt_init_slots(sdata->input,
679				  STMFTS_MAX_FINGERS, INPUT_MT_DIRECT);
680	if (err)
681		return err;
682
683	input_set_drvdata(sdata->input, sdata);
684
685	/*
686	 * stmfts_power_on expects interrupt to be disabled, but
687	 * at this point the device is still off and I do not trust
688	 * the status of the irq line that can generate some spurious
689	 * interrupts. To be on the safe side it's better to not enable
690	 * the interrupts during their request.
691	 */
692	err = devm_request_threaded_irq(&client->dev, client->irq,
693					NULL, stmfts_irq_handler,
694					IRQF_ONESHOT | IRQF_NO_AUTOEN,
695					"stmfts_irq", sdata);
696	if (err)
697		return err;
698
699	dev_dbg(&client->dev, "initializing ST-Microelectronics FTS...\n");
700
701	err = stmfts_power_on(sdata);
702	if (err)
703		return err;
704
705	err = devm_add_action_or_reset(&client->dev, stmfts_power_off, sdata);
706	if (err)
707		return err;
708
709	err = input_register_device(sdata->input);
710	if (err)
711		return err;
712
713	if (sdata->use_key) {
714		err = stmfts_enable_led(sdata);
715		if (err) {
716			/*
717			 * Even if the LEDs have failed to be initialized and
718			 * used in the driver, I can still use the device even
719			 * without LEDs. The ledvdd regulator pointer will be
720			 * used as a flag.
721			 */
722			dev_warn(&client->dev, "unable to use touchkey leds\n");
723			sdata->ledvdd = NULL;
724		}
725	}
726
727	pm_runtime_enable(&client->dev);
728	device_enable_async_suspend(&client->dev);
729
730	return 0;
731}
732
733static void stmfts_remove(struct i2c_client *client)
734{
735	pm_runtime_disable(&client->dev);
736}
737
738static int stmfts_runtime_suspend(struct device *dev)
739{
740	struct stmfts_data *sdata = dev_get_drvdata(dev);
741	int ret;
742
743	ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);
744	if (ret)
745		dev_warn(dev, "failed to suspend device: %d\n", ret);
746
747	return ret;
748}
749
750static int stmfts_runtime_resume(struct device *dev)
751{
752	struct stmfts_data *sdata = dev_get_drvdata(dev);
753	int ret;
754
755	ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_OUT);
756	if (ret)
757		dev_err(dev, "failed to resume device: %d\n", ret);
758
759	return ret;
760}
761
762static int stmfts_suspend(struct device *dev)
763{
764	struct stmfts_data *sdata = dev_get_drvdata(dev);
765
766	stmfts_power_off(sdata);
767
768	return 0;
769}
770
771static int stmfts_resume(struct device *dev)
772{
773	struct stmfts_data *sdata = dev_get_drvdata(dev);
774
775	return stmfts_power_on(sdata);
776}
777
778static const struct dev_pm_ops stmfts_pm_ops = {
779	SYSTEM_SLEEP_PM_OPS(stmfts_suspend, stmfts_resume)
780	RUNTIME_PM_OPS(stmfts_runtime_suspend, stmfts_runtime_resume, NULL)
781};
782
783#ifdef CONFIG_OF
784static const struct of_device_id stmfts_of_match[] = {
785	{ .compatible = "st,stmfts", },
786	{ },
787};
788MODULE_DEVICE_TABLE(of, stmfts_of_match);
789#endif
790
791static const struct i2c_device_id stmfts_id[] = {
792	{ "stmfts", 0 },
793	{ },
794};
795MODULE_DEVICE_TABLE(i2c, stmfts_id);
796
797static struct i2c_driver stmfts_driver = {
798	.driver = {
799		.name = STMFTS_DEV_NAME,
800		.dev_groups = stmfts_sysfs_groups,
801		.of_match_table = of_match_ptr(stmfts_of_match),
802		.pm = pm_ptr(&stmfts_pm_ops),
803		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
804	},
805	.probe = stmfts_probe,
806	.remove = stmfts_remove,
807	.id_table = stmfts_id,
808};
809
810module_i2c_driver(stmfts_driver);
811
812MODULE_AUTHOR("Andi Shyti <andi.shyti@samsung.com>");
813MODULE_DESCRIPTION("STMicroelectronics FTS Touch Screen");
814MODULE_LICENSE("GPL v2");
815