1 /*
2  *  Driver for Goodix Touchscreens
3  *
4  *  Copyright (c) 2014 Red Hat Inc.
5  *  Copyright (c) 2015 K. Merker <merker@debian.org>
6  *
7  *  This code is based on gt9xx.c authored by andrew@goodix.com:
8  *
9  *  2010 - 2012 Goodix Technology.
10  */
11 
12 /*
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms of the GNU General Public License as published by the Free
15  * Software Foundation; version 2 of the License.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/dmi.h>
20 #include <linux/firmware.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/i2c.h>
23 #include <linux/input.h>
24 #include <linux/input/mt.h>
25 #include <linux/module.h>
26 #include <linux/delay.h>
27 #include <linux/irq.h>
28 #include <linux/interrupt.h>
29 #include <linux/slab.h>
30 #include <linux/acpi.h>
31 #include <linux/of.h>
32 #include <asm/unaligned.h>
33 
34 struct goodix_ts_data {
35 	struct i2c_client *client;
36 	struct input_dev *input_dev;
37 	int abs_x_max;
38 	int abs_y_max;
39 	bool swapped_x_y;
40 	bool inverted_x;
41 	bool inverted_y;
42 	unsigned int max_touch_num;
43 	unsigned int int_trigger_type;
44 	int cfg_len;
45 	struct gpio_desc *gpiod_int;
46 	struct gpio_desc *gpiod_rst;
47 	u16 id;
48 	u16 version;
49 	const char *cfg_name;
50 	struct completion firmware_loading_complete;
51 	unsigned long irq_flags;
52 };
53 
54 #define GOODIX_GPIO_INT_NAME		"irq"
55 #define GOODIX_GPIO_RST_NAME		"reset"
56 
57 #define GOODIX_MAX_HEIGHT		4096
58 #define GOODIX_MAX_WIDTH		4096
59 #define GOODIX_INT_TRIGGER		1
60 #define GOODIX_CONTACT_SIZE		8
61 #define GOODIX_MAX_CONTACTS		10
62 
63 #define GOODIX_CONFIG_MAX_LENGTH	240
64 #define GOODIX_CONFIG_911_LENGTH	186
65 #define GOODIX_CONFIG_967_LENGTH	228
66 
67 /* Register defines */
68 #define GOODIX_REG_COMMAND		0x8040
69 #define GOODIX_CMD_SCREEN_OFF		0x05
70 
71 #define GOODIX_READ_COOR_ADDR		0x814E
72 #define GOODIX_REG_CONFIG_DATA		0x8047
73 #define GOODIX_REG_ID			0x8140
74 
75 #define RESOLUTION_LOC		1
76 #define MAX_CONTACTS_LOC	5
77 #define TRIGGER_LOC		6
78 
79 static const unsigned long goodix_irq_flags[] = {
80 	IRQ_TYPE_EDGE_RISING,
81 	IRQ_TYPE_EDGE_FALLING,
82 	IRQ_TYPE_LEVEL_LOW,
83 	IRQ_TYPE_LEVEL_HIGH,
84 };
85 
86 /*
87  * Those tablets have their coordinates origin at the bottom right
88  * of the tablet, as if rotated 180 degrees
89  */
90 static const struct dmi_system_id rotated_screen[] = {
91 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
92 	{
93 		.ident = "WinBook TW100",
94 		.matches = {
95 			DMI_MATCH(DMI_SYS_VENDOR, "WinBook"),
96 			DMI_MATCH(DMI_PRODUCT_NAME, "TW100")
97 		}
98 	},
99 	{
100 		.ident = "WinBook TW700",
101 		.matches = {
102 			DMI_MATCH(DMI_SYS_VENDOR, "WinBook"),
103 			DMI_MATCH(DMI_PRODUCT_NAME, "TW700")
104 		},
105 	},
106 #endif
107 	{}
108 };
109 
110 /**
111  * goodix_i2c_read - read data from a register of the i2c slave device.
112  *
113  * @client: i2c device.
114  * @reg: the register to read from.
115  * @buf: raw write data buffer.
116  * @len: length of the buffer to write
117  */
118 static int goodix_i2c_read(struct i2c_client *client,
119 			   u16 reg, u8 *buf, int len)
120 {
121 	struct i2c_msg msgs[2];
122 	u16 wbuf = cpu_to_be16(reg);
123 	int ret;
124 
125 	msgs[0].flags = 0;
126 	msgs[0].addr  = client->addr;
127 	msgs[0].len   = 2;
128 	msgs[0].buf   = (u8 *)&wbuf;
129 
130 	msgs[1].flags = I2C_M_RD;
131 	msgs[1].addr  = client->addr;
132 	msgs[1].len   = len;
133 	msgs[1].buf   = buf;
134 
135 	ret = i2c_transfer(client->adapter, msgs, 2);
136 	return ret < 0 ? ret : (ret != ARRAY_SIZE(msgs) ? -EIO : 0);
137 }
138 
139 /**
140  * goodix_i2c_write - write data to a register of the i2c slave device.
141  *
142  * @client: i2c device.
143  * @reg: the register to write to.
144  * @buf: raw data buffer to write.
145  * @len: length of the buffer to write
146  */
147 static int goodix_i2c_write(struct i2c_client *client, u16 reg, const u8 *buf,
148 			    unsigned len)
149 {
150 	u8 *addr_buf;
151 	struct i2c_msg msg;
152 	int ret;
153 
154 	addr_buf = kmalloc(len + 2, GFP_KERNEL);
155 	if (!addr_buf)
156 		return -ENOMEM;
157 
158 	addr_buf[0] = reg >> 8;
159 	addr_buf[1] = reg & 0xFF;
160 	memcpy(&addr_buf[2], buf, len);
161 
162 	msg.flags = 0;
163 	msg.addr = client->addr;
164 	msg.buf = addr_buf;
165 	msg.len = len + 2;
166 
167 	ret = i2c_transfer(client->adapter, &msg, 1);
168 	kfree(addr_buf);
169 	return ret < 0 ? ret : (ret != 1 ? -EIO : 0);
170 }
171 
172 static int goodix_i2c_write_u8(struct i2c_client *client, u16 reg, u8 value)
173 {
174 	return goodix_i2c_write(client, reg, &value, sizeof(value));
175 }
176 
177 static int goodix_get_cfg_len(u16 id)
178 {
179 	switch (id) {
180 	case 911:
181 	case 9271:
182 	case 9110:
183 	case 927:
184 	case 928:
185 		return GOODIX_CONFIG_911_LENGTH;
186 
187 	case 912:
188 	case 967:
189 		return GOODIX_CONFIG_967_LENGTH;
190 
191 	default:
192 		return GOODIX_CONFIG_MAX_LENGTH;
193 	}
194 }
195 
196 static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data)
197 {
198 	int touch_num;
199 	int error;
200 
201 	error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR, data,
202 				GOODIX_CONTACT_SIZE + 1);
203 	if (error) {
204 		dev_err(&ts->client->dev, "I2C transfer error: %d\n", error);
205 		return error;
206 	}
207 
208 	if (!(data[0] & 0x80))
209 		return -EAGAIN;
210 
211 	touch_num = data[0] & 0x0f;
212 	if (touch_num > ts->max_touch_num)
213 		return -EPROTO;
214 
215 	if (touch_num > 1) {
216 		data += 1 + GOODIX_CONTACT_SIZE;
217 		error = goodix_i2c_read(ts->client,
218 					GOODIX_READ_COOR_ADDR +
219 						1 + GOODIX_CONTACT_SIZE,
220 					data,
221 					GOODIX_CONTACT_SIZE * (touch_num - 1));
222 		if (error)
223 			return error;
224 	}
225 
226 	return touch_num;
227 }
228 
229 static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
230 {
231 	int id = coor_data[0] & 0x0F;
232 	int input_x = get_unaligned_le16(&coor_data[1]);
233 	int input_y = get_unaligned_le16(&coor_data[3]);
234 	int input_w = get_unaligned_le16(&coor_data[5]);
235 
236 	/* Inversions have to happen before axis swapping */
237 	if (ts->inverted_x)
238 		input_x = ts->abs_x_max - input_x;
239 	if (ts->inverted_y)
240 		input_y = ts->abs_y_max - input_y;
241 	if (ts->swapped_x_y)
242 		swap(input_x, input_y);
243 
244 	input_mt_slot(ts->input_dev, id);
245 	input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
246 	input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
247 	input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
248 	input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
249 	input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
250 }
251 
252 /**
253  * goodix_process_events - Process incoming events
254  *
255  * @ts: our goodix_ts_data pointer
256  *
257  * Called when the IRQ is triggered. Read the current device state, and push
258  * the input events to the user space.
259  */
260 static void goodix_process_events(struct goodix_ts_data *ts)
261 {
262 	u8  point_data[1 + GOODIX_CONTACT_SIZE * GOODIX_MAX_CONTACTS];
263 	int touch_num;
264 	int i;
265 
266 	touch_num = goodix_ts_read_input_report(ts, point_data);
267 	if (touch_num < 0)
268 		return;
269 
270 	for (i = 0; i < touch_num; i++)
271 		goodix_ts_report_touch(ts,
272 				&point_data[1 + GOODIX_CONTACT_SIZE * i]);
273 
274 	input_mt_sync_frame(ts->input_dev);
275 	input_sync(ts->input_dev);
276 }
277 
278 /**
279  * goodix_ts_irq_handler - The IRQ handler
280  *
281  * @irq: interrupt number.
282  * @dev_id: private data pointer.
283  */
284 static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
285 {
286 	struct goodix_ts_data *ts = dev_id;
287 
288 	goodix_process_events(ts);
289 
290 	if (goodix_i2c_write_u8(ts->client, GOODIX_READ_COOR_ADDR, 0) < 0)
291 		dev_err(&ts->client->dev, "I2C write end_cmd error\n");
292 
293 	return IRQ_HANDLED;
294 }
295 
296 static void goodix_free_irq(struct goodix_ts_data *ts)
297 {
298 	devm_free_irq(&ts->client->dev, ts->client->irq, ts);
299 }
300 
301 static int goodix_request_irq(struct goodix_ts_data *ts)
302 {
303 	return devm_request_threaded_irq(&ts->client->dev, ts->client->irq,
304 					 NULL, goodix_ts_irq_handler,
305 					 ts->irq_flags, ts->client->name, ts);
306 }
307 
308 /**
309  * goodix_check_cfg - Checks if config fw is valid
310  *
311  * @ts: goodix_ts_data pointer
312  * @cfg: firmware config data
313  */
314 static int goodix_check_cfg(struct goodix_ts_data *ts,
315 			    const struct firmware *cfg)
316 {
317 	int i, raw_cfg_len;
318 	u8 check_sum = 0;
319 
320 	if (cfg->size > GOODIX_CONFIG_MAX_LENGTH) {
321 		dev_err(&ts->client->dev,
322 			"The length of the config fw is not correct");
323 		return -EINVAL;
324 	}
325 
326 	raw_cfg_len = cfg->size - 2;
327 	for (i = 0; i < raw_cfg_len; i++)
328 		check_sum += cfg->data[i];
329 	check_sum = (~check_sum) + 1;
330 	if (check_sum != cfg->data[raw_cfg_len]) {
331 		dev_err(&ts->client->dev,
332 			"The checksum of the config fw is not correct");
333 		return -EINVAL;
334 	}
335 
336 	if (cfg->data[raw_cfg_len + 1] != 1) {
337 		dev_err(&ts->client->dev,
338 			"Config fw must have Config_Fresh register set");
339 		return -EINVAL;
340 	}
341 
342 	return 0;
343 }
344 
345 /**
346  * goodix_send_cfg - Write fw config to device
347  *
348  * @ts: goodix_ts_data pointer
349  * @cfg: config firmware to write to device
350  */
351 static int goodix_send_cfg(struct goodix_ts_data *ts,
352 			   const struct firmware *cfg)
353 {
354 	int error;
355 
356 	error = goodix_check_cfg(ts, cfg);
357 	if (error)
358 		return error;
359 
360 	error = goodix_i2c_write(ts->client, GOODIX_REG_CONFIG_DATA, cfg->data,
361 				 cfg->size);
362 	if (error) {
363 		dev_err(&ts->client->dev, "Failed to write config data: %d",
364 			error);
365 		return error;
366 	}
367 	dev_dbg(&ts->client->dev, "Config sent successfully.");
368 
369 	/* Let the firmware reconfigure itself, so sleep for 10ms */
370 	usleep_range(10000, 11000);
371 
372 	return 0;
373 }
374 
375 static int goodix_int_sync(struct goodix_ts_data *ts)
376 {
377 	int error;
378 
379 	error = gpiod_direction_output(ts->gpiod_int, 0);
380 	if (error)
381 		return error;
382 
383 	msleep(50);				/* T5: 50ms */
384 
385 	error = gpiod_direction_input(ts->gpiod_int);
386 	if (error)
387 		return error;
388 
389 	return 0;
390 }
391 
392 /**
393  * goodix_reset - Reset device during power on
394  *
395  * @ts: goodix_ts_data pointer
396  */
397 static int goodix_reset(struct goodix_ts_data *ts)
398 {
399 	int error;
400 
401 	/* begin select I2C slave addr */
402 	error = gpiod_direction_output(ts->gpiod_rst, 0);
403 	if (error)
404 		return error;
405 
406 	msleep(20);				/* T2: > 10ms */
407 
408 	/* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */
409 	error = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14);
410 	if (error)
411 		return error;
412 
413 	usleep_range(100, 2000);		/* T3: > 100us */
414 
415 	error = gpiod_direction_output(ts->gpiod_rst, 1);
416 	if (error)
417 		return error;
418 
419 	usleep_range(6000, 10000);		/* T4: > 5ms */
420 
421 	/* end select I2C slave addr */
422 	error = gpiod_direction_input(ts->gpiod_rst);
423 	if (error)
424 		return error;
425 
426 	error = goodix_int_sync(ts);
427 	if (error)
428 		return error;
429 
430 	return 0;
431 }
432 
433 /**
434  * goodix_get_gpio_config - Get GPIO config from ACPI/DT
435  *
436  * @ts: goodix_ts_data pointer
437  */
438 static int goodix_get_gpio_config(struct goodix_ts_data *ts)
439 {
440 	int error;
441 	struct device *dev;
442 	struct gpio_desc *gpiod;
443 
444 	if (!ts->client)
445 		return -EINVAL;
446 	dev = &ts->client->dev;
447 
448 	/* Get the interrupt GPIO pin number */
449 	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN);
450 	if (IS_ERR(gpiod)) {
451 		error = PTR_ERR(gpiod);
452 		if (error != -EPROBE_DEFER)
453 			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
454 				GOODIX_GPIO_INT_NAME, error);
455 		return error;
456 	}
457 
458 	ts->gpiod_int = gpiod;
459 
460 	/* Get the reset line GPIO pin number */
461 	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN);
462 	if (IS_ERR(gpiod)) {
463 		error = PTR_ERR(gpiod);
464 		if (error != -EPROBE_DEFER)
465 			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
466 				GOODIX_GPIO_RST_NAME, error);
467 		return error;
468 	}
469 
470 	ts->gpiod_rst = gpiod;
471 
472 	return 0;
473 }
474 
475 /**
476  * goodix_read_config - Read the embedded configuration of the panel
477  *
478  * @ts: our goodix_ts_data pointer
479  *
480  * Must be called during probe
481  */
482 static void goodix_read_config(struct goodix_ts_data *ts)
483 {
484 	u8 config[GOODIX_CONFIG_MAX_LENGTH];
485 	int error;
486 
487 	error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
488 				config, ts->cfg_len);
489 	if (error) {
490 		dev_warn(&ts->client->dev,
491 			 "Error reading config (%d), using defaults\n",
492 			 error);
493 		ts->abs_x_max = GOODIX_MAX_WIDTH;
494 		ts->abs_y_max = GOODIX_MAX_HEIGHT;
495 		if (ts->swapped_x_y)
496 			swap(ts->abs_x_max, ts->abs_y_max);
497 		ts->int_trigger_type = GOODIX_INT_TRIGGER;
498 		ts->max_touch_num = GOODIX_MAX_CONTACTS;
499 		return;
500 	}
501 
502 	ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
503 	ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
504 	if (ts->swapped_x_y)
505 		swap(ts->abs_x_max, ts->abs_y_max);
506 	ts->int_trigger_type = config[TRIGGER_LOC] & 0x03;
507 	ts->max_touch_num = config[MAX_CONTACTS_LOC] & 0x0f;
508 	if (!ts->abs_x_max || !ts->abs_y_max || !ts->max_touch_num) {
509 		dev_err(&ts->client->dev,
510 			"Invalid config, using defaults\n");
511 		ts->abs_x_max = GOODIX_MAX_WIDTH;
512 		ts->abs_y_max = GOODIX_MAX_HEIGHT;
513 		if (ts->swapped_x_y)
514 			swap(ts->abs_x_max, ts->abs_y_max);
515 		ts->max_touch_num = GOODIX_MAX_CONTACTS;
516 	}
517 
518 	if (dmi_check_system(rotated_screen)) {
519 		ts->inverted_x = true;
520 		ts->inverted_y = true;
521 		dev_dbg(&ts->client->dev,
522 			 "Applying '180 degrees rotated screen' quirk\n");
523 	}
524 }
525 
526 /**
527  * goodix_read_version - Read goodix touchscreen version
528  *
529  * @ts: our goodix_ts_data pointer
530  */
531 static int goodix_read_version(struct goodix_ts_data *ts)
532 {
533 	int error;
534 	u8 buf[6];
535 	char id_str[5];
536 
537 	error = goodix_i2c_read(ts->client, GOODIX_REG_ID, buf, sizeof(buf));
538 	if (error) {
539 		dev_err(&ts->client->dev, "read version failed: %d\n", error);
540 		return error;
541 	}
542 
543 	memcpy(id_str, buf, 4);
544 	id_str[4] = 0;
545 	if (kstrtou16(id_str, 10, &ts->id))
546 		ts->id = 0x1001;
547 
548 	ts->version = get_unaligned_le16(&buf[4]);
549 
550 	dev_info(&ts->client->dev, "ID %d, version: %04x\n", ts->id,
551 		 ts->version);
552 
553 	return 0;
554 }
555 
556 /**
557  * goodix_i2c_test - I2C test function to check if the device answers.
558  *
559  * @client: the i2c client
560  */
561 static int goodix_i2c_test(struct i2c_client *client)
562 {
563 	int retry = 0;
564 	int error;
565 	u8 test;
566 
567 	while (retry++ < 2) {
568 		error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
569 					&test, 1);
570 		if (!error)
571 			return 0;
572 
573 		dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
574 			retry, error);
575 		msleep(20);
576 	}
577 
578 	return error;
579 }
580 
581 /**
582  * goodix_request_input_dev - Allocate, populate and register the input device
583  *
584  * @ts: our goodix_ts_data pointer
585  *
586  * Must be called during probe
587  */
588 static int goodix_request_input_dev(struct goodix_ts_data *ts)
589 {
590 	int error;
591 
592 	ts->input_dev = devm_input_allocate_device(&ts->client->dev);
593 	if (!ts->input_dev) {
594 		dev_err(&ts->client->dev, "Failed to allocate input device.");
595 		return -ENOMEM;
596 	}
597 
598 	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
599 			     0, ts->abs_x_max, 0, 0);
600 	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
601 			     0, ts->abs_y_max, 0, 0);
602 	input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
603 	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
604 
605 	input_mt_init_slots(ts->input_dev, ts->max_touch_num,
606 			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
607 
608 	ts->input_dev->name = "Goodix Capacitive TouchScreen";
609 	ts->input_dev->phys = "input/ts";
610 	ts->input_dev->id.bustype = BUS_I2C;
611 	ts->input_dev->id.vendor = 0x0416;
612 	ts->input_dev->id.product = ts->id;
613 	ts->input_dev->id.version = ts->version;
614 
615 	error = input_register_device(ts->input_dev);
616 	if (error) {
617 		dev_err(&ts->client->dev,
618 			"Failed to register input device: %d", error);
619 		return error;
620 	}
621 
622 	return 0;
623 }
624 
625 /**
626  * goodix_configure_dev - Finish device initialization
627  *
628  * @ts: our goodix_ts_data pointer
629  *
630  * Must be called from probe to finish initialization of the device.
631  * Contains the common initialization code for both devices that
632  * declare gpio pins and devices that do not. It is either called
633  * directly from probe or from request_firmware_wait callback.
634  */
635 static int goodix_configure_dev(struct goodix_ts_data *ts)
636 {
637 	int error;
638 
639 	ts->swapped_x_y = device_property_read_bool(&ts->client->dev,
640 						    "touchscreen-swapped-x-y");
641 	ts->inverted_x = device_property_read_bool(&ts->client->dev,
642 						   "touchscreen-inverted-x");
643 	ts->inverted_y = device_property_read_bool(&ts->client->dev,
644 						   "touchscreen-inverted-y");
645 
646 	goodix_read_config(ts);
647 
648 	error = goodix_request_input_dev(ts);
649 	if (error)
650 		return error;
651 
652 	ts->irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
653 	error = goodix_request_irq(ts);
654 	if (error) {
655 		dev_err(&ts->client->dev, "request IRQ failed: %d\n", error);
656 		return error;
657 	}
658 
659 	return 0;
660 }
661 
662 /**
663  * goodix_config_cb - Callback to finish device init
664  *
665  * @ts: our goodix_ts_data pointer
666  *
667  * request_firmware_wait callback that finishes
668  * initialization of the device.
669  */
670 static void goodix_config_cb(const struct firmware *cfg, void *ctx)
671 {
672 	struct goodix_ts_data *ts = ctx;
673 	int error;
674 
675 	if (cfg) {
676 		/* send device configuration to the firmware */
677 		error = goodix_send_cfg(ts, cfg);
678 		if (error)
679 			goto err_release_cfg;
680 	}
681 
682 	goodix_configure_dev(ts);
683 
684 err_release_cfg:
685 	release_firmware(cfg);
686 	complete_all(&ts->firmware_loading_complete);
687 }
688 
689 static int goodix_ts_probe(struct i2c_client *client,
690 			   const struct i2c_device_id *id)
691 {
692 	struct goodix_ts_data *ts;
693 	int error;
694 
695 	dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
696 
697 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
698 		dev_err(&client->dev, "I2C check functionality failed.\n");
699 		return -ENXIO;
700 	}
701 
702 	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
703 	if (!ts)
704 		return -ENOMEM;
705 
706 	ts->client = client;
707 	i2c_set_clientdata(client, ts);
708 	init_completion(&ts->firmware_loading_complete);
709 
710 	error = goodix_get_gpio_config(ts);
711 	if (error)
712 		return error;
713 
714 	if (ts->gpiod_int && ts->gpiod_rst) {
715 		/* reset the controller */
716 		error = goodix_reset(ts);
717 		if (error) {
718 			dev_err(&client->dev, "Controller reset failed.\n");
719 			return error;
720 		}
721 	}
722 
723 	error = goodix_i2c_test(client);
724 	if (error) {
725 		dev_err(&client->dev, "I2C communication failure: %d\n", error);
726 		return error;
727 	}
728 
729 	error = goodix_read_version(ts);
730 	if (error) {
731 		dev_err(&client->dev, "Read version failed.\n");
732 		return error;
733 	}
734 
735 	ts->cfg_len = goodix_get_cfg_len(ts->id);
736 
737 	if (ts->gpiod_int && ts->gpiod_rst) {
738 		/* update device config */
739 		ts->cfg_name = devm_kasprintf(&client->dev, GFP_KERNEL,
740 					      "goodix_%d_cfg.bin", ts->id);
741 		if (!ts->cfg_name)
742 			return -ENOMEM;
743 
744 		error = request_firmware_nowait(THIS_MODULE, true, ts->cfg_name,
745 						&client->dev, GFP_KERNEL, ts,
746 						goodix_config_cb);
747 		if (error) {
748 			dev_err(&client->dev,
749 				"Failed to invoke firmware loader: %d\n",
750 				error);
751 			return error;
752 		}
753 
754 		return 0;
755 	} else {
756 		error = goodix_configure_dev(ts);
757 		if (error)
758 			return error;
759 	}
760 
761 	return 0;
762 }
763 
764 static int goodix_ts_remove(struct i2c_client *client)
765 {
766 	struct goodix_ts_data *ts = i2c_get_clientdata(client);
767 
768 	if (ts->gpiod_int && ts->gpiod_rst)
769 		wait_for_completion(&ts->firmware_loading_complete);
770 
771 	return 0;
772 }
773 
774 static int __maybe_unused goodix_suspend(struct device *dev)
775 {
776 	struct i2c_client *client = to_i2c_client(dev);
777 	struct goodix_ts_data *ts = i2c_get_clientdata(client);
778 	int error;
779 
780 	/* We need gpio pins to suspend/resume */
781 	if (!ts->gpiod_int || !ts->gpiod_rst)
782 		return 0;
783 
784 	wait_for_completion(&ts->firmware_loading_complete);
785 
786 	/* Free IRQ as IRQ pin is used as output in the suspend sequence */
787 	goodix_free_irq(ts);
788 
789 	/* Output LOW on the INT pin for 5 ms */
790 	error = gpiod_direction_output(ts->gpiod_int, 0);
791 	if (error) {
792 		goodix_request_irq(ts);
793 		return error;
794 	}
795 
796 	usleep_range(5000, 6000);
797 
798 	error = goodix_i2c_write_u8(ts->client, GOODIX_REG_COMMAND,
799 				    GOODIX_CMD_SCREEN_OFF);
800 	if (error) {
801 		dev_err(&ts->client->dev, "Screen off command failed\n");
802 		gpiod_direction_input(ts->gpiod_int);
803 		goodix_request_irq(ts);
804 		return -EAGAIN;
805 	}
806 
807 	/*
808 	 * The datasheet specifies that the interval between sending screen-off
809 	 * command and wake-up should be longer than 58 ms. To avoid waking up
810 	 * sooner, delay 58ms here.
811 	 */
812 	msleep(58);
813 	return 0;
814 }
815 
816 static int __maybe_unused goodix_resume(struct device *dev)
817 {
818 	struct i2c_client *client = to_i2c_client(dev);
819 	struct goodix_ts_data *ts = i2c_get_clientdata(client);
820 	int error;
821 
822 	if (!ts->gpiod_int || !ts->gpiod_rst)
823 		return 0;
824 
825 	/*
826 	 * Exit sleep mode by outputting HIGH level to INT pin
827 	 * for 2ms~5ms.
828 	 */
829 	error = gpiod_direction_output(ts->gpiod_int, 1);
830 	if (error)
831 		return error;
832 
833 	usleep_range(2000, 5000);
834 
835 	error = goodix_int_sync(ts);
836 	if (error)
837 		return error;
838 
839 	error = goodix_request_irq(ts);
840 	if (error)
841 		return error;
842 
843 	return 0;
844 }
845 
846 static SIMPLE_DEV_PM_OPS(goodix_pm_ops, goodix_suspend, goodix_resume);
847 
848 static const struct i2c_device_id goodix_ts_id[] = {
849 	{ "GDIX1001:00", 0 },
850 	{ }
851 };
852 MODULE_DEVICE_TABLE(i2c, goodix_ts_id);
853 
854 #ifdef CONFIG_ACPI
855 static const struct acpi_device_id goodix_acpi_match[] = {
856 	{ "GDIX1001", 0 },
857 	{ }
858 };
859 MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
860 #endif
861 
862 #ifdef CONFIG_OF
863 static const struct of_device_id goodix_of_match[] = {
864 	{ .compatible = "goodix,gt911" },
865 	{ .compatible = "goodix,gt9110" },
866 	{ .compatible = "goodix,gt912" },
867 	{ .compatible = "goodix,gt927" },
868 	{ .compatible = "goodix,gt9271" },
869 	{ .compatible = "goodix,gt928" },
870 	{ .compatible = "goodix,gt967" },
871 	{ }
872 };
873 MODULE_DEVICE_TABLE(of, goodix_of_match);
874 #endif
875 
876 static struct i2c_driver goodix_ts_driver = {
877 	.probe = goodix_ts_probe,
878 	.remove = goodix_ts_remove,
879 	.id_table = goodix_ts_id,
880 	.driver = {
881 		.name = "Goodix-TS",
882 		.acpi_match_table = ACPI_PTR(goodix_acpi_match),
883 		.of_match_table = of_match_ptr(goodix_of_match),
884 		.pm = &goodix_pm_ops,
885 	},
886 };
887 module_i2c_driver(goodix_ts_driver);
888 
889 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
890 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
891 MODULE_DESCRIPTION("Goodix touchscreen driver");
892 MODULE_LICENSE("GPL v2");
893