1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * MELFAS MIP4 Touchscreen
4  *
5  * Copyright (C) 2016 MELFAS Inc.
6  *
7  * Author : Sangwon Jee <jeesw@melfas.com>
8  */
9 
10 #include <linux/acpi.h>
11 #include <linux/delay.h>
12 #include <linux/firmware.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/i2c.h>
15 #include <linux/input.h>
16 #include <linux/input/mt.h>
17 #include <linux/interrupt.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/slab.h>
21 #include <asm/unaligned.h>
22 
23 #define MIP4_DEVICE_NAME	"mip4_ts"
24 
25 /*****************************************************************
26  * Protocol
27  * Version : MIP 4.0 Rev 5.4
28  *****************************************************************/
29 
30 /* Address */
31 #define MIP4_R0_BOOT				0x00
32 #define MIP4_R1_BOOT_MODE			0x01
33 #define MIP4_R1_BOOT_BUF_ADDR			0x10
34 #define MIP4_R1_BOOT_STATUS			0x20
35 #define MIP4_R1_BOOT_CMD			0x30
36 #define MIP4_R1_BOOT_TARGET_ADDR		0x40
37 #define MIP4_R1_BOOT_SIZE			0x44
38 
39 #define MIP4_R0_INFO				0x01
40 #define MIP4_R1_INFO_PRODUCT_NAME		0x00
41 #define MIP4_R1_INFO_RESOLUTION_X		0x10
42 #define MIP4_R1_INFO_RESOLUTION_Y		0x12
43 #define MIP4_R1_INFO_NODE_NUM_X			0x14
44 #define MIP4_R1_INFO_NODE_NUM_Y			0x15
45 #define MIP4_R1_INFO_KEY_NUM			0x16
46 #define MIP4_R1_INFO_PRESSURE_NUM		0x17
47 #define MIP4_R1_INFO_LENGTH_X			0x18
48 #define MIP4_R1_INFO_LENGTH_Y			0x1A
49 #define MIP4_R1_INFO_PPM_X			0x1C
50 #define MIP4_R1_INFO_PPM_Y			0x1D
51 #define MIP4_R1_INFO_VERSION_BOOT		0x20
52 #define MIP4_R1_INFO_VERSION_CORE		0x22
53 #define MIP4_R1_INFO_VERSION_APP		0x24
54 #define MIP4_R1_INFO_VERSION_PARAM		0x26
55 #define MIP4_R1_INFO_SECT_BOOT_START		0x30
56 #define MIP4_R1_INFO_SECT_BOOT_END		0x31
57 #define MIP4_R1_INFO_SECT_CORE_START		0x32
58 #define MIP4_R1_INFO_SECT_CORE_END		0x33
59 #define MIP4_R1_INFO_SECT_APP_START		0x34
60 #define MIP4_R1_INFO_SECT_APP_END		0x35
61 #define MIP4_R1_INFO_SECT_PARAM_START		0x36
62 #define MIP4_R1_INFO_SECT_PARAM_END		0x37
63 #define MIP4_R1_INFO_BUILD_DATE			0x40
64 #define MIP4_R1_INFO_BUILD_TIME			0x44
65 #define MIP4_R1_INFO_CHECKSUM_PRECALC		0x48
66 #define MIP4_R1_INFO_CHECKSUM_REALTIME		0x4A
67 #define MIP4_R1_INFO_PROTOCOL_NAME		0x50
68 #define MIP4_R1_INFO_PROTOCOL_VERSION		0x58
69 #define MIP4_R1_INFO_IC_ID			0x70
70 #define MIP4_R1_INFO_IC_NAME			0x71
71 #define MIP4_R1_INFO_IC_VENDOR_ID		0x75
72 #define MIP4_R1_INFO_IC_HW_CATEGORY		0x77
73 #define MIP4_R1_INFO_CONTACT_THD_SCR		0x78
74 #define MIP4_R1_INFO_CONTACT_THD_KEY		0x7A
75 #define MIP4_R1_INFO_PID				0x7C
76 #define MIP4_R1_INFO_VID				0x7E
77 #define MIP4_R1_INFO_SLAVE_ADDR			0x80
78 
79 #define MIP4_R0_EVENT				0x02
80 #define MIP4_R1_EVENT_SUPPORTED_FUNC		0x00
81 #define MIP4_R1_EVENT_FORMAT			0x04
82 #define MIP4_R1_EVENT_SIZE			0x06
83 #define MIP4_R1_EVENT_PACKET_INFO		0x10
84 #define MIP4_R1_EVENT_PACKET_DATA		0x11
85 
86 #define MIP4_R0_CTRL				0x06
87 #define MIP4_R1_CTRL_READY_STATUS		0x00
88 #define MIP4_R1_CTRL_EVENT_READY		0x01
89 #define MIP4_R1_CTRL_MODE			0x10
90 #define MIP4_R1_CTRL_EVENT_TRIGGER_TYPE		0x11
91 #define MIP4_R1_CTRL_RECALIBRATE		0x12
92 #define MIP4_R1_CTRL_POWER_STATE		0x13
93 #define MIP4_R1_CTRL_GESTURE_TYPE		0x14
94 #define MIP4_R1_CTRL_DISABLE_ESD_ALERT		0x18
95 #define MIP4_R1_CTRL_CHARGER_MODE		0x19
96 #define MIP4_R1_CTRL_HIGH_SENS_MODE		0x1A
97 #define MIP4_R1_CTRL_WINDOW_MODE		0x1B
98 #define MIP4_R1_CTRL_PALM_REJECTION		0x1C
99 #define MIP4_R1_CTRL_EDGE_CORRECTION		0x1D
100 #define MIP4_R1_CTRL_ENTER_GLOVE_MODE		0x1E
101 #define MIP4_R1_CTRL_I2C_ON_LPM			0x1F
102 #define MIP4_R1_CTRL_GESTURE_DEBUG		0x20
103 #define MIP4_R1_CTRL_PALM_EVENT			0x22
104 #define MIP4_R1_CTRL_PROXIMITY_SENSING		0x23
105 
106 /* Value */
107 #define MIP4_BOOT_MODE_BOOT			0x01
108 #define MIP4_BOOT_MODE_APP			0x02
109 
110 #define MIP4_BOOT_STATUS_BUSY			0x05
111 #define MIP4_BOOT_STATUS_ERROR			0x0E
112 #define MIP4_BOOT_STATUS_DONE			0xA0
113 
114 #define MIP4_BOOT_CMD_MASS_ERASE		0x15
115 #define MIP4_BOOT_CMD_PROGRAM			0x54
116 #define MIP4_BOOT_CMD_ERASE			0x8F
117 #define MIP4_BOOT_CMD_WRITE			0xA5
118 #define MIP4_BOOT_CMD_READ			0xC2
119 
120 #define MIP4_EVENT_INPUT_TYPE_KEY		0
121 #define MIP4_EVENT_INPUT_TYPE_SCREEN		1
122 #define MIP4_EVENT_INPUT_TYPE_PROXIMITY		2
123 
124 #define I2C_RETRY_COUNT				3	/* 2~ */
125 
126 #define MIP4_BUF_SIZE				128
127 #define MIP4_MAX_FINGERS			10
128 #define MIP4_MAX_KEYS				4
129 
130 #define MIP4_TOUCH_MAJOR_MIN			0
131 #define MIP4_TOUCH_MAJOR_MAX			255
132 #define MIP4_TOUCH_MINOR_MIN			0
133 #define MIP4_TOUCH_MINOR_MAX			255
134 #define MIP4_PRESSURE_MIN			0
135 #define MIP4_PRESSURE_MAX			255
136 
137 #define MIP4_FW_NAME			"melfas_mip4.fw"
138 #define MIP4_FW_UPDATE_DEBUG		0	/* 0 (default) or 1 */
139 
140 struct mip4_fw_version {
141 	u16 boot;
142 	u16 core;
143 	u16 app;
144 	u16 param;
145 };
146 
147 struct mip4_ts {
148 	struct i2c_client *client;
149 	struct input_dev *input;
150 	struct gpio_desc *gpio_ce;
151 
152 	char phys[32];
153 	char product_name[16];
154 	u16 product_id;
155 	char ic_name[4];
156 	char fw_name[32];
157 
158 	unsigned int max_x;
159 	unsigned int max_y;
160 	u8 node_x;
161 	u8 node_y;
162 	u8 node_key;
163 	unsigned int ppm_x;
164 	unsigned int ppm_y;
165 
166 	struct mip4_fw_version fw_version;
167 
168 	unsigned int event_size;
169 	unsigned int event_format;
170 
171 	unsigned int key_num;
172 	unsigned short key_code[MIP4_MAX_KEYS];
173 
174 	bool wake_irq_enabled;
175 
176 	u8 buf[MIP4_BUF_SIZE];
177 };
178 
179 static int mip4_i2c_xfer(struct mip4_ts *ts,
180 			 char *write_buf, unsigned int write_len,
181 			 char *read_buf, unsigned int read_len)
182 {
183 	struct i2c_msg msg[] = {
184 		{
185 			.addr = ts->client->addr,
186 			.flags = 0,
187 			.buf = write_buf,
188 			.len = write_len,
189 		}, {
190 			.addr = ts->client->addr,
191 			.flags = I2C_M_RD,
192 			.buf = read_buf,
193 			.len = read_len,
194 		},
195 	};
196 	int retry = I2C_RETRY_COUNT;
197 	int res;
198 	int error;
199 
200 	do {
201 		res = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
202 		if (res == ARRAY_SIZE(msg))
203 			return 0;
204 
205 		error = res < 0 ? res : -EIO;
206 		dev_err(&ts->client->dev,
207 			"%s - i2c_transfer failed: %d (%d)\n",
208 			__func__, error, res);
209 	} while (--retry);
210 
211 	return error;
212 }
213 
214 static void mip4_parse_fw_version(const u8 *buf, struct mip4_fw_version *v)
215 {
216 	v->boot  = get_unaligned_le16(buf + 0);
217 	v->core  = get_unaligned_le16(buf + 2);
218 	v->app   = get_unaligned_le16(buf + 4);
219 	v->param = get_unaligned_le16(buf + 6);
220 }
221 
222 /*
223  * Read chip firmware version
224  */
225 static int mip4_get_fw_version(struct mip4_ts *ts)
226 {
227 	u8 cmd[] = { MIP4_R0_INFO, MIP4_R1_INFO_VERSION_BOOT };
228 	u8 buf[sizeof(ts->fw_version)];
229 	int error;
230 
231 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, sizeof(buf));
232 	if (error) {
233 		memset(&ts->fw_version, 0xff, sizeof(ts->fw_version));
234 		return error;
235 	}
236 
237 	mip4_parse_fw_version(buf, &ts->fw_version);
238 
239 	return 0;
240 }
241 
242 /*
243  * Fetch device characteristics
244  */
245 static int mip4_query_device(struct mip4_ts *ts)
246 {
247 	union i2c_smbus_data dummy;
248 	int error;
249 	u8 cmd[2];
250 	u8 buf[14];
251 
252 	/*
253 	 * Make sure there is something at this address as we do not
254 	 * consider subsequent failures as fatal.
255 	 */
256 	if (i2c_smbus_xfer(ts->client->adapter, ts->client->addr,
257 			   0, I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
258 		dev_err(&ts->client->dev, "nothing at this address\n");
259 		return -ENXIO;
260 	}
261 
262 	/* Product name */
263 	cmd[0] = MIP4_R0_INFO;
264 	cmd[1] = MIP4_R1_INFO_PRODUCT_NAME;
265 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd),
266 			      ts->product_name, sizeof(ts->product_name));
267 	if (error)
268 		dev_warn(&ts->client->dev,
269 			 "Failed to retrieve product name: %d\n", error);
270 	else
271 		dev_dbg(&ts->client->dev, "product name: %.*s\n",
272 			(int)sizeof(ts->product_name), ts->product_name);
273 
274 	/* Product ID */
275 	cmd[0] = MIP4_R0_INFO;
276 	cmd[1] = MIP4_R1_INFO_PID;
277 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 2);
278 	if (error) {
279 		dev_warn(&ts->client->dev,
280 			 "Failed to retrieve product id: %d\n", error);
281 	} else {
282 		ts->product_id = get_unaligned_le16(&buf[0]);
283 		dev_dbg(&ts->client->dev, "product id: %04X\n", ts->product_id);
284 	}
285 
286 	/* Firmware name */
287 	snprintf(ts->fw_name, sizeof(ts->fw_name),
288 		"melfas_mip4_%04X.fw", ts->product_id);
289 	dev_dbg(&ts->client->dev, "firmware name: %s\n", ts->fw_name);
290 
291 	/* IC name */
292 	cmd[0] = MIP4_R0_INFO;
293 	cmd[1] = MIP4_R1_INFO_IC_NAME;
294 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd),
295 			      ts->ic_name, sizeof(ts->ic_name));
296 	if (error)
297 		dev_warn(&ts->client->dev,
298 			 "Failed to retrieve IC name: %d\n", error);
299 	else
300 		dev_dbg(&ts->client->dev, "IC name: %.*s\n",
301 			(int)sizeof(ts->ic_name), ts->ic_name);
302 
303 	/* Firmware version */
304 	error = mip4_get_fw_version(ts);
305 	if (error)
306 		dev_warn(&ts->client->dev,
307 			"Failed to retrieve FW version: %d\n", error);
308 	else
309 		dev_dbg(&ts->client->dev, "F/W Version: %04X %04X %04X %04X\n",
310 			 ts->fw_version.boot, ts->fw_version.core,
311 			 ts->fw_version.app, ts->fw_version.param);
312 
313 	/* Resolution */
314 	cmd[0] = MIP4_R0_INFO;
315 	cmd[1] = MIP4_R1_INFO_RESOLUTION_X;
316 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 14);
317 	if (error) {
318 		dev_warn(&ts->client->dev,
319 			 "Failed to retrieve touchscreen parameters: %d\n",
320 			 error);
321 	} else {
322 		ts->max_x = get_unaligned_le16(&buf[0]);
323 		ts->max_y = get_unaligned_le16(&buf[2]);
324 		dev_dbg(&ts->client->dev, "max_x: %d, max_y: %d\n",
325 			ts->max_x, ts->max_y);
326 
327 		ts->node_x = buf[4];
328 		ts->node_y = buf[5];
329 		ts->node_key = buf[6];
330 		dev_dbg(&ts->client->dev,
331 			"node_x: %d, node_y: %d, node_key: %d\n",
332 			ts->node_x, ts->node_y, ts->node_key);
333 
334 		ts->ppm_x = buf[12];
335 		ts->ppm_y = buf[13];
336 		dev_dbg(&ts->client->dev, "ppm_x: %d, ppm_y: %d\n",
337 			ts->ppm_x, ts->ppm_y);
338 
339 		/* Key ts */
340 		if (ts->node_key > 0)
341 			ts->key_num = ts->node_key;
342 	}
343 
344 	/* Protocol */
345 	cmd[0] = MIP4_R0_EVENT;
346 	cmd[1] = MIP4_R1_EVENT_SUPPORTED_FUNC;
347 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 7);
348 	if (error) {
349 		dev_warn(&ts->client->dev,
350 			"Failed to retrieve device type: %d\n", error);
351 		ts->event_format = 0xff;
352 	} else {
353 		ts->event_format = get_unaligned_le16(&buf[4]);
354 		ts->event_size = buf[6];
355 		dev_dbg(&ts->client->dev, "event_format: %d, event_size: %d\n",
356 			ts->event_format, ts->event_size);
357 
358 		if (ts->event_format == 2 || ts->event_format > 3)
359 			dev_warn(&ts->client->dev,
360 				 "Unknown event format %d\n", ts->event_format);
361 	}
362 
363 	return 0;
364 }
365 
366 static int mip4_power_on(struct mip4_ts *ts)
367 {
368 	if (ts->gpio_ce) {
369 		gpiod_set_value_cansleep(ts->gpio_ce, 1);
370 
371 		/* Booting delay : 200~300ms */
372 		usleep_range(200 * 1000, 300 * 1000);
373 	}
374 
375 	return 0;
376 }
377 
378 static void mip4_power_off(struct mip4_ts *ts)
379 {
380 	if (ts->gpio_ce)
381 		gpiod_set_value_cansleep(ts->gpio_ce, 0);
382 }
383 
384 /*
385  * Clear touch input event status
386  */
387 static void mip4_clear_input(struct mip4_ts *ts)
388 {
389 	int i;
390 
391 	/* Screen */
392 	for (i = 0; i < MIP4_MAX_FINGERS; i++) {
393 		input_mt_slot(ts->input, i);
394 		input_mt_report_slot_inactive(ts->input);
395 	}
396 
397 	/* Keys */
398 	for (i = 0; i < ts->key_num; i++)
399 		input_report_key(ts->input, ts->key_code[i], 0);
400 
401 	input_sync(ts->input);
402 }
403 
404 static int mip4_enable(struct mip4_ts *ts)
405 {
406 	int error;
407 
408 	error = mip4_power_on(ts);
409 	if (error)
410 		return error;
411 
412 	enable_irq(ts->client->irq);
413 
414 	return 0;
415 }
416 
417 static void mip4_disable(struct mip4_ts *ts)
418 {
419 	disable_irq(ts->client->irq);
420 
421 	mip4_power_off(ts);
422 
423 	mip4_clear_input(ts);
424 }
425 
426 /*****************************************************************
427  * Input handling
428  *****************************************************************/
429 
430 static void mip4_report_keys(struct mip4_ts *ts, u8 *packet)
431 {
432 	u8 key;
433 	bool down;
434 
435 	switch (ts->event_format) {
436 	case 0:
437 	case 1:
438 		key = packet[0] & 0x0F;
439 		down = packet[0] & 0x80;
440 		break;
441 
442 	case 3:
443 	default:
444 		key = packet[0] & 0x0F;
445 		down = packet[1] & 0x01;
446 		break;
447 	}
448 
449 	/* Report key event */
450 	if (key >= 1 && key <= ts->key_num) {
451 		unsigned short keycode = ts->key_code[key - 1];
452 
453 		dev_dbg(&ts->client->dev,
454 			"Key - ID: %d, keycode: %d, state: %d\n",
455 			key, keycode, down);
456 
457 		input_event(ts->input, EV_MSC, MSC_SCAN, keycode);
458 		input_report_key(ts->input, keycode, down);
459 
460 	} else {
461 		dev_err(&ts->client->dev, "Unknown key: %d\n", key);
462 	}
463 }
464 
465 static void mip4_report_touch(struct mip4_ts *ts, u8 *packet)
466 {
467 	int id;
468 	bool __always_unused hover;
469 	bool palm;
470 	bool state;
471 	u16 x, y;
472 	u8 __always_unused pressure_stage = 0;
473 	u8 pressure;
474 	u8 __always_unused size;
475 	u8 touch_major;
476 	u8 touch_minor;
477 
478 	switch (ts->event_format) {
479 	case 0:
480 	case 1:
481 		/* Touch only */
482 		state = packet[0] & BIT(7);
483 		hover = packet[0] & BIT(5);
484 		palm = packet[0] & BIT(4);
485 		id = (packet[0] & 0x0F) - 1;
486 		x = ((packet[1] & 0x0F) << 8) | packet[2];
487 		y = (((packet[1] >> 4) & 0x0F) << 8) |
488 			packet[3];
489 		pressure = packet[4];
490 		size = packet[5];
491 		if (ts->event_format == 0) {
492 			touch_major = packet[5];
493 			touch_minor = packet[5];
494 		} else {
495 			touch_major = packet[6];
496 			touch_minor = packet[7];
497 		}
498 		break;
499 
500 	case 3:
501 	default:
502 		/* Touch + Force(Pressure) */
503 		id = (packet[0] & 0x0F) - 1;
504 		hover = packet[1] & BIT(2);
505 		palm = packet[1] & BIT(1);
506 		state = packet[1] & BIT(0);
507 		x = ((packet[2] & 0x0F) << 8) | packet[3];
508 		y = (((packet[2] >> 4) & 0x0F) << 8) |
509 			packet[4];
510 		size = packet[6];
511 		pressure_stage = (packet[7] & 0xF0) >> 4;
512 		pressure = ((packet[7] & 0x0F) << 8) |
513 			packet[8];
514 		touch_major = packet[9];
515 		touch_minor = packet[10];
516 		break;
517 	}
518 
519 	dev_dbg(&ts->client->dev,
520 		"Screen - Slot: %d State: %d X: %04d Y: %04d Z: %d\n",
521 		id, state, x, y, pressure);
522 
523 	if (unlikely(id < 0 || id >= MIP4_MAX_FINGERS)) {
524 		dev_err(&ts->client->dev, "Screen - invalid slot ID: %d\n", id);
525 		goto out;
526 	}
527 
528 	input_mt_slot(ts->input, id);
529 	if (input_mt_report_slot_state(ts->input,
530 				       palm ? MT_TOOL_PALM : MT_TOOL_FINGER,
531 				       state)) {
532 		input_report_abs(ts->input, ABS_MT_POSITION_X, x);
533 		input_report_abs(ts->input, ABS_MT_POSITION_Y, y);
534 		input_report_abs(ts->input, ABS_MT_PRESSURE, pressure);
535 		input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR, touch_major);
536 		input_report_abs(ts->input, ABS_MT_TOUCH_MINOR, touch_minor);
537 	}
538 
539 out:
540 	input_mt_sync_frame(ts->input);
541 }
542 
543 static int mip4_handle_packet(struct mip4_ts *ts, u8 *packet)
544 {
545 	u8 type;
546 
547 	switch (ts->event_format) {
548 	case 0:
549 	case 1:
550 		type = (packet[0] & 0x40) >> 6;
551 		break;
552 
553 	case 3:
554 		type = (packet[0] & 0xF0) >> 4;
555 		break;
556 
557 	default:
558 		/* Should not happen unless we have corrupted firmware */
559 		return -EINVAL;
560 	}
561 
562 	dev_dbg(&ts->client->dev, "Type: %d\n", type);
563 
564 	/* Report input event */
565 	switch (type) {
566 	case MIP4_EVENT_INPUT_TYPE_KEY:
567 		mip4_report_keys(ts, packet);
568 		break;
569 
570 	case MIP4_EVENT_INPUT_TYPE_SCREEN:
571 		mip4_report_touch(ts, packet);
572 		break;
573 
574 	default:
575 		dev_err(&ts->client->dev, "Unknown event type: %d\n", type);
576 		break;
577 	}
578 
579 	return 0;
580 }
581 
582 static irqreturn_t mip4_interrupt(int irq, void *dev_id)
583 {
584 	struct mip4_ts *ts = dev_id;
585 	struct i2c_client *client = ts->client;
586 	unsigned int i;
587 	int error;
588 	u8 cmd[2];
589 	u8 size;
590 	bool alert;
591 
592 	/* Read packet info */
593 	cmd[0] = MIP4_R0_EVENT;
594 	cmd[1] = MIP4_R1_EVENT_PACKET_INFO;
595 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), ts->buf, 1);
596 	if (error) {
597 		dev_err(&client->dev,
598 			"Failed to read packet info: %d\n", error);
599 		goto out;
600 	}
601 
602 	size = ts->buf[0] & 0x7F;
603 	alert = ts->buf[0] & BIT(7);
604 	dev_dbg(&client->dev, "packet size: %d, alert: %d\n", size, alert);
605 
606 	/* Check size */
607 	if (!size) {
608 		dev_err(&client->dev, "Empty packet\n");
609 		goto out;
610 	}
611 
612 	/* Read packet data */
613 	cmd[0] = MIP4_R0_EVENT;
614 	cmd[1] = MIP4_R1_EVENT_PACKET_DATA;
615 	error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), ts->buf, size);
616 	if (error) {
617 		dev_err(&client->dev,
618 			"Failed to read packet data: %d\n", error);
619 		goto out;
620 	}
621 
622 	if (alert) {
623 		dev_dbg(&client->dev, "Alert: %d\n", ts->buf[0]);
624 	} else {
625 		for (i = 0; i < size; i += ts->event_size) {
626 			error = mip4_handle_packet(ts, &ts->buf[i]);
627 			if (error)
628 				break;
629 		}
630 
631 		input_sync(ts->input);
632 	}
633 
634 out:
635 	return IRQ_HANDLED;
636 }
637 
638 static int mip4_input_open(struct input_dev *dev)
639 {
640 	struct mip4_ts *ts = input_get_drvdata(dev);
641 
642 	return mip4_enable(ts);
643 }
644 
645 static void mip4_input_close(struct input_dev *dev)
646 {
647 	struct mip4_ts *ts = input_get_drvdata(dev);
648 
649 	mip4_disable(ts);
650 }
651 
652 /*****************************************************************
653  * Firmware update
654  *****************************************************************/
655 
656 /* Firmware Info */
657 #define MIP4_BL_PAGE_SIZE		512	/* 512 */
658 #define MIP4_BL_PACKET_SIZE		512	/* 512, 256, 128, 64, ... */
659 
660 /*
661  * Firmware binary tail info
662  */
663 
664 struct mip4_bin_tail {
665 	u8 tail_mark[4];
666 	u8 chip_name[4];
667 
668 	__le32 bin_start_addr;
669 	__le32 bin_length;
670 
671 	__le16 ver_boot;
672 	__le16 ver_core;
673 	__le16 ver_app;
674 	__le16 ver_param;
675 
676 	u8 boot_start;
677 	u8 boot_end;
678 	u8 core_start;
679 	u8 core_end;
680 	u8 app_start;
681 	u8 app_end;
682 	u8 param_start;
683 	u8 param_end;
684 
685 	u8 checksum_type;
686 	u8 hw_category;
687 
688 	__le16 param_id;
689 	__le32 param_length;
690 	__le32 build_date;
691 	__le32 build_time;
692 
693 	__le32 reserved1;
694 	__le32 reserved2;
695 	__le16 reserved3;
696 	__le16 tail_size;
697 	__le32 crc;
698 } __packed;
699 
700 #define MIP4_BIN_TAIL_MARK	"MBT\001"
701 #define MIP4_BIN_TAIL_SIZE	(sizeof(struct mip4_bin_tail))
702 
703 /*
704 * Bootloader - Read status
705 */
706 static int mip4_bl_read_status(struct mip4_ts *ts)
707 {
708 	u8 cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_STATUS };
709 	u8 result;
710 	struct i2c_msg msg[] = {
711 		{
712 			.addr = ts->client->addr,
713 			.flags = 0,
714 			.buf = cmd,
715 			.len = sizeof(cmd),
716 		}, {
717 			.addr = ts->client->addr,
718 			.flags = I2C_M_RD,
719 			.buf = &result,
720 			.len = sizeof(result),
721 		},
722 	};
723 	int ret;
724 	int error;
725 	int retry = 1000;
726 
727 	do {
728 		ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
729 		if (ret != ARRAY_SIZE(msg)) {
730 			error = ret < 0 ? ret : -EIO;
731 			dev_err(&ts->client->dev,
732 				"Failed to read bootloader status: %d\n",
733 				error);
734 			return error;
735 		}
736 
737 		switch (result) {
738 		case MIP4_BOOT_STATUS_DONE:
739 			dev_dbg(&ts->client->dev, "%s - done\n", __func__);
740 			return 0;
741 
742 		case MIP4_BOOT_STATUS_ERROR:
743 			dev_err(&ts->client->dev, "Bootloader failure\n");
744 			return -EIO;
745 
746 		case MIP4_BOOT_STATUS_BUSY:
747 			dev_dbg(&ts->client->dev, "%s - Busy\n", __func__);
748 			error = -EBUSY;
749 			break;
750 
751 		default:
752 			dev_err(&ts->client->dev,
753 				"Unexpected bootloader status: %#02x\n",
754 				result);
755 			error = -EINVAL;
756 			break;
757 		}
758 
759 		usleep_range(1000, 2000);
760 	} while (--retry);
761 
762 	return error;
763 }
764 
765 /*
766 * Bootloader - Change mode
767 */
768 static int mip4_bl_change_mode(struct mip4_ts *ts, u8 mode)
769 {
770 	u8 mode_chg_cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_MODE, mode };
771 	u8 mode_read_cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_MODE };
772 	u8 result;
773 	struct i2c_msg msg[] = {
774 		{
775 			.addr = ts->client->addr,
776 			.flags = 0,
777 			.buf = mode_read_cmd,
778 			.len = sizeof(mode_read_cmd),
779 		}, {
780 			.addr = ts->client->addr,
781 			.flags = I2C_M_RD,
782 			.buf = &result,
783 			.len = sizeof(result),
784 		},
785 	};
786 	int retry = 10;
787 	int ret;
788 	int error;
789 
790 	do {
791 		/* Send mode change command */
792 		ret = i2c_master_send(ts->client,
793 				      mode_chg_cmd, sizeof(mode_chg_cmd));
794 		if (ret != sizeof(mode_chg_cmd)) {
795 			error = ret < 0 ? ret : -EIO;
796 			dev_err(&ts->client->dev,
797 				"Failed to send %d mode change: %d (%d)\n",
798 				mode, error, ret);
799 			return error;
800 		}
801 
802 		dev_dbg(&ts->client->dev,
803 			"Sent mode change request (mode: %d)\n", mode);
804 
805 		/* Wait */
806 		msleep(1000);
807 
808 		/* Verify target mode */
809 		ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
810 		if (ret != ARRAY_SIZE(msg)) {
811 			error = ret < 0 ? ret : -EIO;
812 			dev_err(&ts->client->dev,
813 				"Failed to read device mode: %d\n", error);
814 			return error;
815 		}
816 
817 		dev_dbg(&ts->client->dev,
818 			"Current device mode: %d, want: %d\n", result, mode);
819 
820 		if (result == mode)
821 			return 0;
822 
823 	} while (--retry);
824 
825 	return -EIO;
826 }
827 
828 /*
829  * Bootloader - Start bootloader mode
830  */
831 static int mip4_bl_enter(struct mip4_ts *ts)
832 {
833 	return mip4_bl_change_mode(ts, MIP4_BOOT_MODE_BOOT);
834 }
835 
836 /*
837  * Bootloader - Exit bootloader mode
838  */
839 static int mip4_bl_exit(struct mip4_ts *ts)
840 {
841 	return mip4_bl_change_mode(ts, MIP4_BOOT_MODE_APP);
842 }
843 
844 static int mip4_bl_get_address(struct mip4_ts *ts, u16 *buf_addr)
845 {
846 	u8 cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_BUF_ADDR };
847 	u8 result[sizeof(u16)];
848 	struct i2c_msg msg[] = {
849 		{
850 			.addr = ts->client->addr,
851 			.flags = 0,
852 			.buf = cmd,
853 			.len = sizeof(cmd),
854 		}, {
855 			.addr = ts->client->addr,
856 			.flags = I2C_M_RD,
857 			.buf = result,
858 			.len = sizeof(result),
859 		},
860 	};
861 	int ret;
862 	int error;
863 
864 	ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
865 	if (ret != ARRAY_SIZE(msg)) {
866 		error = ret < 0 ? ret : -EIO;
867 		dev_err(&ts->client->dev,
868 			"Failed to retrieve bootloader buffer address: %d\n",
869 			error);
870 		return error;
871 	}
872 
873 	*buf_addr = get_unaligned_le16(result);
874 	dev_dbg(&ts->client->dev,
875 		"Bootloader buffer address %#04x\n", *buf_addr);
876 
877 	return 0;
878 }
879 
880 static int mip4_bl_program_page(struct mip4_ts *ts, int offset,
881 				const u8 *data, int length, u16 buf_addr)
882 {
883 	u8 cmd[6];
884 	u8 *data_buf;
885 	u16 buf_offset;
886 	int ret;
887 	int error;
888 
889 	dev_dbg(&ts->client->dev, "Writing page @%#06x (%d)\n",
890 		offset, length);
891 
892 	if (length > MIP4_BL_PAGE_SIZE || length % MIP4_BL_PACKET_SIZE) {
893 		dev_err(&ts->client->dev,
894 			"Invalid page length: %d\n", length);
895 		return -EINVAL;
896 	}
897 
898 	data_buf = kmalloc(2 + MIP4_BL_PACKET_SIZE, GFP_KERNEL);
899 	if (!data_buf)
900 		return -ENOMEM;
901 
902 	/* Addr */
903 	cmd[0] = MIP4_R0_BOOT;
904 	cmd[1] = MIP4_R1_BOOT_TARGET_ADDR;
905 	put_unaligned_le32(offset, &cmd[2]);
906 	ret = i2c_master_send(ts->client, cmd, 6);
907 	if (ret != 6) {
908 		error = ret < 0 ? ret : -EIO;
909 		dev_err(&ts->client->dev,
910 			"Failed to send write page address: %d\n", error);
911 		goto out;
912 	}
913 
914 	/* Size */
915 	cmd[0] = MIP4_R0_BOOT;
916 	cmd[1] = MIP4_R1_BOOT_SIZE;
917 	put_unaligned_le32(length, &cmd[2]);
918 	ret = i2c_master_send(ts->client, cmd, 6);
919 	if (ret != 6) {
920 		error = ret < 0 ? ret : -EIO;
921 		dev_err(&ts->client->dev,
922 			"Failed to send write page size: %d\n", error);
923 		goto out;
924 	}
925 
926 	/* Data */
927 	for (buf_offset = 0;
928 	     buf_offset < length;
929 	     buf_offset += MIP4_BL_PACKET_SIZE) {
930 		dev_dbg(&ts->client->dev,
931 			"writing chunk at %#04x (size %d)\n",
932 			buf_offset, MIP4_BL_PACKET_SIZE);
933 		put_unaligned_be16(buf_addr + buf_offset, data_buf);
934 		memcpy(&data_buf[2], &data[buf_offset], MIP4_BL_PACKET_SIZE);
935 		ret = i2c_master_send(ts->client,
936 				      data_buf, 2 + MIP4_BL_PACKET_SIZE);
937 		if (ret != 2 + MIP4_BL_PACKET_SIZE) {
938 			error = ret < 0 ? ret : -EIO;
939 			dev_err(&ts->client->dev,
940 				"Failed to read chunk at %#04x (size %d): %d\n",
941 				buf_offset, MIP4_BL_PACKET_SIZE, error);
942 			goto out;
943 		}
944 	}
945 
946 	/* Command */
947 	cmd[0] = MIP4_R0_BOOT;
948 	cmd[1] = MIP4_R1_BOOT_CMD;
949 	cmd[2] = MIP4_BOOT_CMD_PROGRAM;
950 	ret = i2c_master_send(ts->client, cmd, 3);
951 	if (ret != 3) {
952 		error = ret < 0 ? ret : -EIO;
953 		dev_err(&ts->client->dev,
954 			"Failed to send 'write' command: %d\n", error);
955 		goto out;
956 	}
957 
958 	/* Status */
959 	error = mip4_bl_read_status(ts);
960 
961 out:
962 	kfree(data_buf);
963 	return error ? error : 0;
964 }
965 
966 static int mip4_bl_verify_page(struct mip4_ts *ts, int offset,
967 			       const u8 *data, int length, int buf_addr)
968 {
969 	u8 cmd[8];
970 	u8 *read_buf;
971 	int buf_offset;
972 	struct i2c_msg msg[] = {
973 		{
974 			.addr = ts->client->addr,
975 			.flags = 0,
976 			.buf = cmd,
977 			.len = 2,
978 		}, {
979 			.addr = ts->client->addr,
980 			.flags = I2C_M_RD,
981 			.len = MIP4_BL_PACKET_SIZE,
982 		},
983 	};
984 	int ret;
985 	int error;
986 
987 	dev_dbg(&ts->client->dev, "Validating page @%#06x (%d)\n",
988 		offset, length);
989 
990 	/* Addr */
991 	cmd[0] = MIP4_R0_BOOT;
992 	cmd[1] = MIP4_R1_BOOT_TARGET_ADDR;
993 	put_unaligned_le32(offset, &cmd[2]);
994 	ret = i2c_master_send(ts->client, cmd, 6);
995 	if (ret != 6) {
996 		error = ret < 0 ? ret : -EIO;
997 		dev_err(&ts->client->dev,
998 			"Failed to send read page address: %d\n", error);
999 		return error;
1000 	}
1001 
1002 	/* Size */
1003 	cmd[0] = MIP4_R0_BOOT;
1004 	cmd[1] = MIP4_R1_BOOT_SIZE;
1005 	put_unaligned_le32(length, &cmd[2]);
1006 	ret = i2c_master_send(ts->client, cmd, 6);
1007 	if (ret != 6) {
1008 		error = ret < 0 ? ret : -EIO;
1009 		dev_err(&ts->client->dev,
1010 			"Failed to send read page size: %d\n", error);
1011 		return error;
1012 	}
1013 
1014 	/* Command */
1015 	cmd[0] = MIP4_R0_BOOT;
1016 	cmd[1] = MIP4_R1_BOOT_CMD;
1017 	cmd[2] = MIP4_BOOT_CMD_READ;
1018 	ret = i2c_master_send(ts->client, cmd, 3);
1019 	if (ret != 3) {
1020 		error = ret < 0 ? ret : -EIO;
1021 		dev_err(&ts->client->dev,
1022 			"Failed to send 'read' command: %d\n", error);
1023 		return error;
1024 	}
1025 
1026 	/* Status */
1027 	error = mip4_bl_read_status(ts);
1028 	if (error)
1029 		return error;
1030 
1031 	/* Read */
1032 	msg[1].buf = read_buf = kmalloc(MIP4_BL_PACKET_SIZE, GFP_KERNEL);
1033 	if (!read_buf)
1034 		return -ENOMEM;
1035 
1036 	for (buf_offset = 0;
1037 	     buf_offset < length;
1038 	     buf_offset += MIP4_BL_PACKET_SIZE) {
1039 		dev_dbg(&ts->client->dev,
1040 			"reading chunk at %#04x (size %d)\n",
1041 			buf_offset, MIP4_BL_PACKET_SIZE);
1042 		put_unaligned_be16(buf_addr + buf_offset, cmd);
1043 		ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
1044 		if (ret != ARRAY_SIZE(msg)) {
1045 			error = ret < 0 ? ret : -EIO;
1046 			dev_err(&ts->client->dev,
1047 				"Failed to read chunk at %#04x (size %d): %d\n",
1048 				buf_offset, MIP4_BL_PACKET_SIZE, error);
1049 			break;
1050 		}
1051 
1052 		if (memcmp(&data[buf_offset], read_buf, MIP4_BL_PACKET_SIZE)) {
1053 			dev_err(&ts->client->dev,
1054 				"Failed to validate chunk at %#04x (size %d)\n",
1055 				buf_offset, MIP4_BL_PACKET_SIZE);
1056 #if MIP4_FW_UPDATE_DEBUG
1057 			print_hex_dump(KERN_DEBUG,
1058 				       MIP4_DEVICE_NAME " F/W File: ",
1059 				       DUMP_PREFIX_OFFSET, 16, 1,
1060 				       data + offset, MIP4_BL_PACKET_SIZE,
1061 				       false);
1062 			print_hex_dump(KERN_DEBUG,
1063 				       MIP4_DEVICE_NAME " F/W Chip: ",
1064 				       DUMP_PREFIX_OFFSET, 16, 1,
1065 				       read_buf, MIP4_BL_PAGE_SIZE, false);
1066 #endif
1067 			error = -EINVAL;
1068 			break;
1069 		}
1070 	}
1071 
1072 	kfree(read_buf);
1073 	return error ? error : 0;
1074 }
1075 
1076 /*
1077  * Flash chip firmware
1078  */
1079 static int mip4_flash_fw(struct mip4_ts *ts,
1080 			 const u8 *fw_data, u32 fw_size, u32 fw_offset)
1081 {
1082 	struct i2c_client *client = ts->client;
1083 	int offset;
1084 	u16 buf_addr;
1085 	int error, error2;
1086 
1087 	/* Enter bootloader mode */
1088 	dev_dbg(&client->dev, "Entering bootloader mode\n");
1089 
1090 	error = mip4_bl_enter(ts);
1091 	if (error) {
1092 		dev_err(&client->dev,
1093 			"Failed to enter bootloader mode: %d\n",
1094 			error);
1095 		return error;
1096 	}
1097 
1098 	/* Read info */
1099 	error = mip4_bl_get_address(ts, &buf_addr);
1100 	if (error)
1101 		goto exit_bl;
1102 
1103 	/* Program & Verify */
1104 	dev_dbg(&client->dev,
1105 		"Program & Verify, page size: %d, packet size: %d\n",
1106 		MIP4_BL_PAGE_SIZE, MIP4_BL_PACKET_SIZE);
1107 
1108 	for (offset = fw_offset;
1109 	     offset < fw_offset + fw_size;
1110 	     offset += MIP4_BL_PAGE_SIZE) {
1111 		/* Program */
1112 		error = mip4_bl_program_page(ts, offset, fw_data + offset,
1113 					     MIP4_BL_PAGE_SIZE, buf_addr);
1114 		if (error)
1115 			break;
1116 
1117 		/* Verify */
1118 		error = mip4_bl_verify_page(ts, offset, fw_data + offset,
1119 					    MIP4_BL_PAGE_SIZE, buf_addr);
1120 		if (error)
1121 			break;
1122 	}
1123 
1124 exit_bl:
1125 	/* Exit bootloader mode */
1126 	dev_dbg(&client->dev, "Exiting bootloader mode\n");
1127 
1128 	error2 = mip4_bl_exit(ts);
1129 	if (error2) {
1130 		dev_err(&client->dev,
1131 			"Failed to exit bootloader mode: %d\n", error2);
1132 		if (!error)
1133 			error = error2;
1134 	}
1135 
1136 	/* Reset chip */
1137 	mip4_power_off(ts);
1138 	mip4_power_on(ts);
1139 
1140 	mip4_query_device(ts);
1141 
1142 	/* Refresh device parameters */
1143 	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0);
1144 	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0);
1145 	input_set_abs_params(ts->input, ABS_X, 0, ts->max_x, 0, 0);
1146 	input_set_abs_params(ts->input, ABS_Y, 0, ts->max_y, 0, 0);
1147 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->ppm_x);
1148 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->ppm_y);
1149 	input_abs_set_res(ts->input, ABS_X, ts->ppm_x);
1150 	input_abs_set_res(ts->input, ABS_Y, ts->ppm_y);
1151 
1152 	return error ? error : 0;
1153 }
1154 
1155 static int mip4_parse_firmware(struct mip4_ts *ts, const struct firmware *fw,
1156 			       u32 *fw_offset_start, u32 *fw_size,
1157 			       const struct mip4_bin_tail **pfw_info)
1158 {
1159 	const struct mip4_bin_tail *fw_info;
1160 	struct mip4_fw_version fw_version;
1161 	u16 tail_size;
1162 
1163 	if (fw->size < MIP4_BIN_TAIL_SIZE) {
1164 		dev_err(&ts->client->dev,
1165 			"Invalid firmware, size mismatch (tail %zd vs %zd)\n",
1166 			MIP4_BIN_TAIL_SIZE, fw->size);
1167 		return -EINVAL;
1168 	}
1169 
1170 	fw_info = (const void *)&fw->data[fw->size - MIP4_BIN_TAIL_SIZE];
1171 
1172 #if MIP4_FW_UPDATE_DEBUG
1173 	print_hex_dump(KERN_ERR, MIP4_DEVICE_NAME " Bin Info: ",
1174 		       DUMP_PREFIX_OFFSET, 16, 1, *fw_info, tail_size, false);
1175 #endif
1176 
1177 	tail_size = get_unaligned_le16(&fw_info->tail_size);
1178 	if (tail_size != MIP4_BIN_TAIL_SIZE) {
1179 		dev_err(&ts->client->dev,
1180 			"wrong tail size: %d (expected %zd)\n",
1181 			tail_size, MIP4_BIN_TAIL_SIZE);
1182 		return -EINVAL;
1183 	}
1184 
1185 	/* Check bin format */
1186 	if (memcmp(fw_info->tail_mark, MIP4_BIN_TAIL_MARK,
1187 		   sizeof(fw_info->tail_mark))) {
1188 		dev_err(&ts->client->dev,
1189 			"unable to locate tail marker (%*ph vs %*ph)\n",
1190 			(int)sizeof(fw_info->tail_mark), fw_info->tail_mark,
1191 			(int)sizeof(fw_info->tail_mark), MIP4_BIN_TAIL_MARK);
1192 		return -EINVAL;
1193 	}
1194 
1195 	*fw_offset_start = get_unaligned_le32(&fw_info->bin_start_addr);
1196 	*fw_size = get_unaligned_le32(&fw_info->bin_length);
1197 
1198 	dev_dbg(&ts->client->dev,
1199 		"F/W Data offset: %#08x, size: %d\n",
1200 		*fw_offset_start, *fw_size);
1201 
1202 	if (*fw_size % MIP4_BL_PAGE_SIZE) {
1203 		dev_err(&ts->client->dev,
1204 			"encoded fw length %d is not multiple of pages (%d)\n",
1205 			*fw_size, MIP4_BL_PAGE_SIZE);
1206 		return -EINVAL;
1207 	}
1208 
1209 	if (fw->size != *fw_offset_start + *fw_size) {
1210 		dev_err(&ts->client->dev,
1211 			"Wrong firmware size, expected %d bytes, got %zd\n",
1212 			*fw_offset_start + *fw_size, fw->size);
1213 		return -EINVAL;
1214 	}
1215 
1216 	mip4_parse_fw_version((const u8 *)&fw_info->ver_boot, &fw_version);
1217 
1218 	dev_dbg(&ts->client->dev,
1219 		"F/W file version %04X %04X %04X %04X\n",
1220 		fw_version.boot, fw_version.core,
1221 		fw_version.app, fw_version.param);
1222 
1223 	dev_dbg(&ts->client->dev, "F/W chip version: %04X %04X %04X %04X\n",
1224 		 ts->fw_version.boot, ts->fw_version.core,
1225 		 ts->fw_version.app, ts->fw_version.param);
1226 
1227 	/* Check F/W type */
1228 	if (fw_version.boot != 0xEEEE && fw_version.boot != 0xFFFF &&
1229 	    fw_version.core == 0xEEEE &&
1230 	    fw_version.app == 0xEEEE &&
1231 	    fw_version.param == 0xEEEE) {
1232 		dev_dbg(&ts->client->dev, "F/W type: Bootloader\n");
1233 	} else if (fw_version.boot == 0xEEEE &&
1234 		   fw_version.core != 0xEEEE && fw_version.core != 0xFFFF &&
1235 		   fw_version.app != 0xEEEE && fw_version.app != 0xFFFF &&
1236 		   fw_version.param != 0xEEEE && fw_version.param != 0xFFFF) {
1237 		dev_dbg(&ts->client->dev, "F/W type: Main\n");
1238 	} else {
1239 		dev_err(&ts->client->dev, "Wrong firmware type\n");
1240 		return -EINVAL;
1241 	}
1242 
1243 	return 0;
1244 }
1245 
1246 static int mip4_execute_fw_update(struct mip4_ts *ts, const struct firmware *fw)
1247 {
1248 	const struct mip4_bin_tail *fw_info;
1249 	u32 fw_start_offset;
1250 	u32 fw_size;
1251 	int retires = 3;
1252 	int error;
1253 
1254 	error = mip4_parse_firmware(ts, fw,
1255 				    &fw_start_offset, &fw_size, &fw_info);
1256 	if (error)
1257 		return error;
1258 
1259 	if (input_device_enabled(ts->input)) {
1260 		disable_irq(ts->client->irq);
1261 	} else {
1262 		error = mip4_power_on(ts);
1263 		if (error)
1264 			return error;
1265 	}
1266 
1267 	/* Update firmware */
1268 	do {
1269 		error = mip4_flash_fw(ts, fw->data, fw_size, fw_start_offset);
1270 		if (!error)
1271 			break;
1272 	} while (--retires);
1273 
1274 	if (error)
1275 		dev_err(&ts->client->dev,
1276 			"Failed to flash firmware: %d\n", error);
1277 
1278 	/* Enable IRQ */
1279 	if (input_device_enabled(ts->input))
1280 		enable_irq(ts->client->irq);
1281 	else
1282 		mip4_power_off(ts);
1283 
1284 	return error ? error : 0;
1285 }
1286 
1287 static ssize_t mip4_sysfs_fw_update(struct device *dev,
1288 				    struct device_attribute *attr,
1289 				    const char *buf, size_t count)
1290 {
1291 	struct i2c_client *client = to_i2c_client(dev);
1292 	struct mip4_ts *ts = i2c_get_clientdata(client);
1293 	const struct firmware *fw;
1294 	int error;
1295 
1296 	error = request_firmware(&fw, ts->fw_name, dev);
1297 	if (error) {
1298 		dev_err(&ts->client->dev,
1299 			"Failed to retrieve firmware %s: %d\n",
1300 			ts->fw_name, error);
1301 		return error;
1302 	}
1303 
1304 	/*
1305 	 * Take input mutex to prevent racing with itself and also with
1306 	 * userspace opening and closing the device and also suspend/resume
1307 	 * transitions.
1308 	 */
1309 	mutex_lock(&ts->input->mutex);
1310 
1311 	error = mip4_execute_fw_update(ts, fw);
1312 
1313 	mutex_unlock(&ts->input->mutex);
1314 
1315 	release_firmware(fw);
1316 
1317 	if (error) {
1318 		dev_err(&ts->client->dev,
1319 			"Firmware update failed: %d\n", error);
1320 		return error;
1321 	}
1322 
1323 	return count;
1324 }
1325 
1326 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, mip4_sysfs_fw_update);
1327 
1328 static ssize_t mip4_sysfs_read_fw_version(struct device *dev,
1329 					  struct device_attribute *attr,
1330 					  char *buf)
1331 {
1332 	struct i2c_client *client = to_i2c_client(dev);
1333 	struct mip4_ts *ts = i2c_get_clientdata(client);
1334 	size_t count;
1335 
1336 	/* Take lock to prevent racing with firmware update */
1337 	mutex_lock(&ts->input->mutex);
1338 
1339 	count = snprintf(buf, PAGE_SIZE, "%04X %04X %04X %04X\n",
1340 			 ts->fw_version.boot, ts->fw_version.core,
1341 			 ts->fw_version.app, ts->fw_version.param);
1342 
1343 	mutex_unlock(&ts->input->mutex);
1344 
1345 	return count;
1346 }
1347 
1348 static DEVICE_ATTR(fw_version, S_IRUGO, mip4_sysfs_read_fw_version, NULL);
1349 
1350 static ssize_t mip4_sysfs_read_hw_version(struct device *dev,
1351 					  struct device_attribute *attr,
1352 					  char *buf)
1353 {
1354 	struct i2c_client *client = to_i2c_client(dev);
1355 	struct mip4_ts *ts = i2c_get_clientdata(client);
1356 	size_t count;
1357 
1358 	/* Take lock to prevent racing with firmware update */
1359 	mutex_lock(&ts->input->mutex);
1360 
1361 	/*
1362 	 * product_name shows the name or version of the hardware
1363 	 * paired with current firmware in the chip.
1364 	 */
1365 	count = snprintf(buf, PAGE_SIZE, "%.*s\n",
1366 			 (int)sizeof(ts->product_name), ts->product_name);
1367 
1368 	mutex_unlock(&ts->input->mutex);
1369 
1370 	return count;
1371 }
1372 
1373 static DEVICE_ATTR(hw_version, S_IRUGO, mip4_sysfs_read_hw_version, NULL);
1374 
1375 static ssize_t mip4_sysfs_read_product_id(struct device *dev,
1376 					  struct device_attribute *attr,
1377 					  char *buf)
1378 {
1379 	struct i2c_client *client = to_i2c_client(dev);
1380 	struct mip4_ts *ts = i2c_get_clientdata(client);
1381 	size_t count;
1382 
1383 	mutex_lock(&ts->input->mutex);
1384 
1385 	count = snprintf(buf, PAGE_SIZE, "%04X\n", ts->product_id);
1386 
1387 	mutex_unlock(&ts->input->mutex);
1388 
1389 	return count;
1390 }
1391 
1392 static DEVICE_ATTR(product_id, S_IRUGO, mip4_sysfs_read_product_id, NULL);
1393 
1394 static ssize_t mip4_sysfs_read_ic_name(struct device *dev,
1395 					  struct device_attribute *attr,
1396 					  char *buf)
1397 {
1398 	struct i2c_client *client = to_i2c_client(dev);
1399 	struct mip4_ts *ts = i2c_get_clientdata(client);
1400 	size_t count;
1401 
1402 	mutex_lock(&ts->input->mutex);
1403 
1404 	count = snprintf(buf, PAGE_SIZE, "%.*s\n",
1405 			 (int)sizeof(ts->ic_name), ts->ic_name);
1406 
1407 	mutex_unlock(&ts->input->mutex);
1408 
1409 	return count;
1410 }
1411 
1412 static DEVICE_ATTR(ic_name, S_IRUGO, mip4_sysfs_read_ic_name, NULL);
1413 
1414 static struct attribute *mip4_attrs[] = {
1415 	&dev_attr_fw_version.attr,
1416 	&dev_attr_hw_version.attr,
1417 	&dev_attr_product_id.attr,
1418 	&dev_attr_ic_name.attr,
1419 	&dev_attr_update_fw.attr,
1420 	NULL,
1421 };
1422 
1423 static const struct attribute_group mip4_attr_group = {
1424 	.attrs = mip4_attrs,
1425 };
1426 
1427 static int mip4_probe(struct i2c_client *client)
1428 {
1429 	struct mip4_ts *ts;
1430 	struct input_dev *input;
1431 	int error;
1432 
1433 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1434 		dev_err(&client->dev, "Not supported I2C adapter\n");
1435 		return -ENXIO;
1436 	}
1437 
1438 	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
1439 	if (!ts)
1440 		return -ENOMEM;
1441 
1442 	input = devm_input_allocate_device(&client->dev);
1443 	if (!input)
1444 		return -ENOMEM;
1445 
1446 	ts->client = client;
1447 	ts->input = input;
1448 
1449 	snprintf(ts->phys, sizeof(ts->phys),
1450 		 "%s/input0", dev_name(&client->dev));
1451 
1452 	ts->gpio_ce = devm_gpiod_get_optional(&client->dev,
1453 					      "ce", GPIOD_OUT_LOW);
1454 	if (IS_ERR(ts->gpio_ce)) {
1455 		error = PTR_ERR(ts->gpio_ce);
1456 		if (error != -EPROBE_DEFER)
1457 			dev_err(&client->dev,
1458 				"Failed to get gpio: %d\n", error);
1459 		return error;
1460 	}
1461 
1462 	error = mip4_power_on(ts);
1463 	if (error)
1464 		return error;
1465 	error = mip4_query_device(ts);
1466 	mip4_power_off(ts);
1467 	if (error)
1468 		return error;
1469 
1470 	input->name = "MELFAS MIP4 Touchscreen";
1471 	input->phys = ts->phys;
1472 
1473 	input->id.bustype = BUS_I2C;
1474 	input->id.vendor = 0x13c5;
1475 	input->id.product = ts->product_id;
1476 
1477 	input->open = mip4_input_open;
1478 	input->close = mip4_input_close;
1479 
1480 	input_set_drvdata(input, ts);
1481 
1482 	input->keycode = ts->key_code;
1483 	input->keycodesize = sizeof(*ts->key_code);
1484 	input->keycodemax = ts->key_num;
1485 
1486 	input_set_abs_params(input, ABS_MT_TOOL_TYPE, 0, MT_TOOL_PALM, 0, 0);
1487 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0);
1488 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0);
1489 	input_set_abs_params(input, ABS_MT_PRESSURE,
1490 			     MIP4_PRESSURE_MIN, MIP4_PRESSURE_MAX, 0, 0);
1491 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR,
1492 			     MIP4_TOUCH_MAJOR_MIN, MIP4_TOUCH_MAJOR_MAX, 0, 0);
1493 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR,
1494 			     MIP4_TOUCH_MINOR_MIN, MIP4_TOUCH_MINOR_MAX, 0, 0);
1495 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->ppm_x);
1496 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->ppm_y);
1497 
1498 	error = input_mt_init_slots(input, MIP4_MAX_FINGERS, INPUT_MT_DIRECT);
1499 	if (error)
1500 		return error;
1501 
1502 	i2c_set_clientdata(client, ts);
1503 
1504 	error = devm_request_threaded_irq(&client->dev, client->irq,
1505 					  NULL, mip4_interrupt,
1506 					  IRQF_ONESHOT | IRQF_NO_AUTOEN,
1507 					  MIP4_DEVICE_NAME, ts);
1508 	if (error) {
1509 		dev_err(&client->dev,
1510 			"Failed to request interrupt %d: %d\n",
1511 			client->irq, error);
1512 		return error;
1513 	}
1514 
1515 	error = input_register_device(input);
1516 	if (error) {
1517 		dev_err(&client->dev,
1518 			"Failed to register input device: %d\n", error);
1519 		return error;
1520 	}
1521 
1522 	error = devm_device_add_group(&client->dev, &mip4_attr_group);
1523 	if (error) {
1524 		dev_err(&client->dev,
1525 			"Failed to create sysfs attribute group: %d\n", error);
1526 		return error;
1527 	}
1528 
1529 	return 0;
1530 }
1531 
1532 static int mip4_suspend(struct device *dev)
1533 {
1534 	struct i2c_client *client = to_i2c_client(dev);
1535 	struct mip4_ts *ts = i2c_get_clientdata(client);
1536 	struct input_dev *input = ts->input;
1537 
1538 	mutex_lock(&input->mutex);
1539 
1540 	if (device_may_wakeup(dev))
1541 		ts->wake_irq_enabled = enable_irq_wake(client->irq) == 0;
1542 	else if (input_device_enabled(input))
1543 		mip4_disable(ts);
1544 
1545 	mutex_unlock(&input->mutex);
1546 
1547 	return 0;
1548 }
1549 
1550 static int mip4_resume(struct device *dev)
1551 {
1552 	struct i2c_client *client = to_i2c_client(dev);
1553 	struct mip4_ts *ts = i2c_get_clientdata(client);
1554 	struct input_dev *input = ts->input;
1555 
1556 	mutex_lock(&input->mutex);
1557 
1558 	if (ts->wake_irq_enabled)
1559 		disable_irq_wake(client->irq);
1560 	else if (input_device_enabled(input))
1561 		mip4_enable(ts);
1562 
1563 	mutex_unlock(&input->mutex);
1564 
1565 	return 0;
1566 }
1567 
1568 static DEFINE_SIMPLE_DEV_PM_OPS(mip4_pm_ops, mip4_suspend, mip4_resume);
1569 
1570 #ifdef CONFIG_OF
1571 static const struct of_device_id mip4_of_match[] = {
1572 	{ .compatible = "melfas,"MIP4_DEVICE_NAME, },
1573 	{ },
1574 };
1575 MODULE_DEVICE_TABLE(of, mip4_of_match);
1576 #endif
1577 
1578 #ifdef CONFIG_ACPI
1579 static const struct acpi_device_id mip4_acpi_match[] = {
1580 	{ "MLFS0000", 0},
1581 	{ },
1582 };
1583 MODULE_DEVICE_TABLE(acpi, mip4_acpi_match);
1584 #endif
1585 
1586 static const struct i2c_device_id mip4_i2c_ids[] = {
1587 	{ MIP4_DEVICE_NAME, 0 },
1588 	{ },
1589 };
1590 MODULE_DEVICE_TABLE(i2c, mip4_i2c_ids);
1591 
1592 static struct i2c_driver mip4_driver = {
1593 	.id_table = mip4_i2c_ids,
1594 	.probe = mip4_probe,
1595 	.driver = {
1596 		.name = MIP4_DEVICE_NAME,
1597 		.of_match_table = of_match_ptr(mip4_of_match),
1598 		.acpi_match_table = ACPI_PTR(mip4_acpi_match),
1599 		.pm = pm_sleep_ptr(&mip4_pm_ops),
1600 	},
1601 };
1602 module_i2c_driver(mip4_driver);
1603 
1604 MODULE_DESCRIPTION("MELFAS MIP4 Touchscreen");
1605 MODULE_AUTHOR("Sangwon Jee <jeesw@melfas.com>");
1606 MODULE_LICENSE("GPL");
1607