summaryrefslogtreecommitdiff
path: root/drivers/input/touchscreen/elants_i2c.c
blob: 17540bdb1eaf7b03af79c009a34a3e659565ba18 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Elan Microelectronics touch panels with I2C interface
 *
 * Copyright (C) 2014 Elan Microelectronics Corporation.
 * Scott Liu <scott.liu@emc.com.tw>
 *
 * This code is partly based on hid-multitouch.c:
 *
 *  Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
 *  Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
 *  Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
 *
 * This code is partly based on i2c-hid.c:
 *
 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
 * Copyright (c) 2012 Red Hat, Inc
 */


#include <linux/bits.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/async.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/firmware.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/acpi.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/uuid.h>
#include <asm/unaligned.h>

/* Device, Driver information */
#define DEVICE_NAME	"elants_i2c"

/* Convert from rows or columns into resolution */
#define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))

/* FW header data */
#define HEADER_SIZE		4
#define FW_HDR_TYPE		0
#define FW_HDR_COUNT		1
#define FW_HDR_LENGTH		2

/* Buffer mode Queue Header information */
#define QUEUE_HEADER_SINGLE	0x62
#define QUEUE_HEADER_NORMAL	0X63
#define QUEUE_HEADER_WAIT	0x64
#define QUEUE_HEADER_NORMAL2	0x66

/* Command header definition */
#define CMD_HEADER_WRITE	0x54
#define CMD_HEADER_READ		0x53
#define CMD_HEADER_6B_READ	0x5B
#define CMD_HEADER_ROM_READ	0x96
#define CMD_HEADER_RESP		0x52
#define CMD_HEADER_6B_RESP	0x9B
#define CMD_HEADER_ROM_RESP	0x95
#define CMD_HEADER_HELLO	0x55
#define CMD_HEADER_REK		0x66

/* FW position data */
#define PACKET_SIZE_OLD		40
#define PACKET_SIZE		55
#define MAX_CONTACT_NUM		10
#define FW_POS_HEADER		0
#define FW_POS_STATE		1
#define FW_POS_TOTAL		2
#define FW_POS_XY		3
#define FW_POS_TOOL_TYPE	33
#define FW_POS_CHECKSUM		34
#define FW_POS_WIDTH		35
#define FW_POS_PRESSURE		45

#define HEADER_REPORT_10_FINGER	0x62

/* Header (4 bytes) plus 3 full 10-finger packets */
#define MAX_PACKET_SIZE		169

#define BOOT_TIME_DELAY_MS	50

/* FW read command, 0x53 0x?? 0x0, 0x01 */
#define E_ELAN_INFO_FW_VER	0x00
#define E_ELAN_INFO_BC_VER	0x10
#define E_ELAN_INFO_X_RES	0x60
#define E_ELAN_INFO_Y_RES	0x63
#define E_ELAN_INFO_REK		0xD0
#define E_ELAN_INFO_TEST_VER	0xE0
#define E_ELAN_INFO_FW_ID	0xF0
#define E_INFO_OSR		0xD6
#define E_INFO_PHY_SCAN		0xD7
#define E_INFO_PHY_DRIVER	0xD8

/* FW write command, 0x54 0x?? 0x0, 0x01 */
#define E_POWER_STATE_SLEEP	0x50
#define E_POWER_STATE_RESUME	0x58

#define MAX_RETRIES		3
#define MAX_FW_UPDATE_RETRIES	30

#define ELAN_FW_PAGESIZE	132

/* calibration timeout definition */
#define ELAN_CALI_TIMEOUT_MSEC	12000

#define ELAN_POWERON_DELAY_USEC	500
#define ELAN_RESET_DELAY_MSEC	20

enum elants_chip_id {
	EKTH3500,
	EKTF3624,
};

enum elants_state {
	ELAN_STATE_NORMAL,
	ELAN_WAIT_QUEUE_HEADER,
	ELAN_WAIT_RECALIBRATION,
};

enum elants_iap_mode {
	ELAN_IAP_OPERATIONAL,
	ELAN_IAP_RECOVERY,
};

/* struct elants_data - represents state of Elan touchscreen device */
struct elants_data {
	struct i2c_client *client;
	struct input_dev *input;

	struct regulator *vcc33;
	struct regulator *vccio;
	struct gpio_desc *reset_gpio;

	u16 fw_version;
	u8 test_version;
	u8 solution_version;
	u8 bc_version;
	u8 iap_version;
	u16 hw_version;
	u8 major_res;
	unsigned int x_res;	/* resolution in units/mm */
	unsigned int y_res;
	unsigned int x_max;
	unsigned int y_max;
	unsigned int phy_x;
	unsigned int phy_y;
	struct touchscreen_properties prop;

	enum elants_state state;
	enum elants_chip_id chip_id;
	enum elants_iap_mode iap_mode;

	/* Guards against concurrent access to the device via sysfs */
	struct mutex sysfs_mutex;

	u8 cmd_resp[HEADER_SIZE];
	struct completion cmd_done;

	bool wake_irq_enabled;
	bool keep_power_in_suspend;

	/* Must be last to be used for DMA operations */
	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
};

static int elants_i2c_send(struct i2c_client *client,
			   const void *data, size_t size)
{
	int ret;

	ret = i2c_master_send(client, data, size);
	if (ret == size)
		return 0;

	if (ret >= 0)
		ret = -EIO;

	dev_err(&client->dev, "%s failed (%*ph): %d\n",
		__func__, (int)size, data, ret);

	return ret;
}

static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
{
	int ret;

	ret = i2c_master_recv(client, data, size);
	if (ret == size)
		return 0;

	if (ret >= 0)
		ret = -EIO;

	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);

	return ret;
}

static int elants_i2c_execute_command(struct i2c_client *client,
				      const u8 *cmd, size_t cmd_size,
				      u8 *resp, size_t resp_size,
				      int retries, const char *cmd_name)
{
	struct i2c_msg msgs[2];
	int ret;
	u8 expected_response;

	switch (cmd[0]) {
	case CMD_HEADER_READ:
		expected_response = CMD_HEADER_RESP;
		break;

	case CMD_HEADER_6B_READ:
		expected_response = CMD_HEADER_6B_RESP;
		break;

	case CMD_HEADER_ROM_READ:
		expected_response = CMD_HEADER_ROM_RESP;
		break;

	default:
		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
			cmd_name, (int)cmd_size, cmd);
		return -EINVAL;
	}

	for (;;) {
		msgs[0].addr = client->addr;
		msgs[0].flags = client->flags & I2C_M_TEN;
		msgs[0].len = cmd_size;
		msgs[0].buf = (u8 *)cmd;

		msgs[1].addr = client->addr;
		msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
		msgs[1].flags |= I2C_M_RD;
		msgs[1].len = resp_size;
		msgs[1].buf = resp;

		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
		if (ret < 0) {
			if (--retries > 0) {
				dev_dbg(&client->dev,
					"(%s) I2C transfer failed: %pe (retrying)\n",
					cmd_name, ERR_PTR(ret));
				continue;
			}

			dev_err(&client->dev,
				"(%s) I2C transfer failed: %pe\n",
				cmd_name, ERR_PTR(ret));
			return ret;
		}

		if (ret != ARRAY_SIZE(msgs) ||
		    resp[FW_HDR_TYPE] != expected_response) {
			if (--retries > 0) {
				dev_dbg(&client->dev,
					"(%s) unexpected response: %*ph (retrying)\n",
					cmd_name, ret, resp);
				continue;
			}

			dev_err(&client->dev,
				"(%s) unexpected response: %*ph\n",
				cmd_name, ret, resp);
			return -EIO;
		}

		return 0;
	}
}

static int elants_i2c_calibrate(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int ret, error;
	static const u8 w_flashkey[] = { CMD_HEADER_WRITE, 0xC0, 0xE1, 0x5A };
	static const u8 rek[] = { CMD_HEADER_WRITE, 0x29, 0x00, 0x01 };
	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };

	disable_irq(client->irq);

	ts->state = ELAN_WAIT_RECALIBRATION;
	reinit_completion(&ts->cmd_done);

	elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
	elants_i2c_send(client, rek, sizeof(rek));

	enable_irq(client->irq);

	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));

	ts->state = ELAN_STATE_NORMAL;

	if (ret <= 0) {
		error = ret < 0 ? ret : -ETIMEDOUT;
		dev_err(&client->dev,
			"error while waiting for calibration to complete: %d\n",
			error);
		return error;
	}

	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
		dev_err(&client->dev,
			"unexpected calibration response: %*ph\n",
			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
		return -EINVAL;
	}

	return 0;
}

static int elants_i2c_sw_reset(struct i2c_client *client)
{
	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
	int error;

	error = elants_i2c_send(client, soft_rst_cmd,
				sizeof(soft_rst_cmd));
	if (error) {
		dev_err(&client->dev, "software reset failed: %d\n", error);
		return error;
	}

	/*
	 * We should wait at least 10 msec (but no more than 40) before
	 * sending fastboot or IAP command to the device.
	 */
	msleep(30);

	return 0;
}

static u16 elants_i2c_parse_version(u8 *buf)
{
	return get_unaligned_be32(buf) >> 4;
}

static int elants_i2c_query_hw_version(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int retry_cnt = MAX_RETRIES;
	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
	u8 resp[HEADER_SIZE];
	int error;

	while (retry_cnt--) {
		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
						   resp, sizeof(resp), 1,
						   "read fw id");
		if (error)
			return error;

		ts->hw_version = elants_i2c_parse_version(resp);
		if (ts->hw_version != 0xffff)
			return 0;
	}

	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);

	return -EINVAL;
}

static int elants_i2c_query_fw_version(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int retry_cnt = MAX_RETRIES;
	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
	u8 resp[HEADER_SIZE];
	int error;

	while (retry_cnt--) {
		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
						   resp, sizeof(resp), 1,
						   "read fw version");
		if (error)
			return error;

		ts->fw_version = elants_i2c_parse_version(resp);
		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
			return 0;

		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
			(int)sizeof(resp), resp);
	}

	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);

	return -EINVAL;
}

static int elants_i2c_query_test_version(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int error;
	u16 version;
	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
	u8 resp[HEADER_SIZE];

	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
					   resp, sizeof(resp), MAX_RETRIES,
					   "read test version");
	if (error) {
		dev_err(&client->dev, "Failed to read test version\n");
		return error;
	}

	version = elants_i2c_parse_version(resp);
	ts->test_version = version >> 8;
	ts->solution_version = version & 0xff;

	return 0;
}

static int elants_i2c_query_bc_version(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
	u8 resp[HEADER_SIZE];
	u16 version;
	int error;

	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
					   resp, sizeof(resp), 1,
					   "read BC version");
	if (error)
		return error;

	version = elants_i2c_parse_version(resp);
	ts->bc_version = version >> 8;
	ts->iap_version = version & 0xff;

	return 0;
}

static int elants_i2c_query_ts_info_ektf(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int error;
	u8 resp[4];
	u16 phy_x, phy_y;
	const u8 get_xres_cmd[] = {
		CMD_HEADER_READ, E_ELAN_INFO_X_RES, 0x00, 0x00
	};
	const u8 get_yres_cmd[] = {
		CMD_HEADER_READ, E_ELAN_INFO_Y_RES, 0x00, 0x00
	};

	/* Get X/Y size in mm */
	error = elants_i2c_execute_command(client, get_xres_cmd,
					   sizeof(get_xres_cmd),
					   resp, sizeof(resp), 1,
					   "get X size");
	if (error)
		return error;

	phy_x = resp[2] | ((resp[3] & 0xF0) << 4);

	error = elants_i2c_execute_command(client, get_yres_cmd,
					   sizeof(get_yres_cmd),
					   resp, sizeof(resp), 1,
					   "get Y size");
	if (error)
		return error;

	phy_y = resp[2] | ((resp[3] & 0xF0) << 4);

	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);

	ts->phy_x = phy_x;
	ts->phy_y = phy_y;

	/* eKTF doesn't report max size, set it to default values */
	ts->x_max = 2240 - 1;
	ts->y_max = 1408 - 1;

	return 0;
}

static int elants_i2c_query_ts_info_ekth(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int error;
	u8 resp[17];
	u16 phy_x, phy_y, rows, cols, osr;
	const u8 get_resolution_cmd[] = {
		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
	};
	const u8 get_osr_cmd[] = {
		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
	};
	const u8 get_physical_scan_cmd[] = {
		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
	};
	const u8 get_physical_drive_cmd[] = {
		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
	};

	/* Get trace number */
	error = elants_i2c_execute_command(client,
					   get_resolution_cmd,
					   sizeof(get_resolution_cmd),
					   resp, sizeof(resp), 1,
					   "get resolution");
	if (error)
		return error;

	rows = resp[2] + resp[6] + resp[10];
	cols = resp[3] + resp[7] + resp[11];

	/* Get report resolution value of ABS_MT_TOUCH_MAJOR */
	ts->major_res = resp[16];

	/* Process mm_to_pixel information */
	error = elants_i2c_execute_command(client,
					   get_osr_cmd, sizeof(get_osr_cmd),
					   resp, sizeof(resp), 1, "get osr");
	if (error)
		return error;

	osr = resp[3];

	error = elants_i2c_execute_command(client,
					   get_physical_scan_cmd,
					   sizeof(get_physical_scan_cmd),
					   resp, sizeof(resp), 1,
					   "get physical scan");
	if (error)
		return error;

	phy_x = get_unaligned_be16(&resp[2]);

	error = elants_i2c_execute_command(client,
					   get_physical_drive_cmd,
					   sizeof(get_physical_drive_cmd),
					   resp, sizeof(resp), 1,
					   "get physical drive");
	if (error)
		return error;

	phy_y = get_unaligned_be16(&resp[2]);

	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);

	if (rows == 0 || cols == 0 || osr == 0) {
		dev_warn(&client->dev,
			 "invalid trace number data: %d, %d, %d\n",
			 rows, cols, osr);
	} else {
		/* translate trace number to TS resolution */
		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
		ts->phy_x = phy_x;
		ts->phy_y = phy_y;
	}

	return 0;
}

static int elants_i2c_fastboot(struct i2c_client *client)
{
	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
	int error;

	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
	if (error) {
		dev_err(&client->dev, "boot failed: %d\n", error);
		return error;
	}

	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
	return 0;
}

static int elants_i2c_initialize(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	int error, error2, retry_cnt;
	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
	u8 buf[HEADER_SIZE];

	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
		error = elants_i2c_sw_reset(client);
		if (error) {
			/* Continue initializing if it's the last try */
			if (retry_cnt < MAX_RETRIES - 1)
				continue;
		}

		error = elants_i2c_fastboot(client);
		if (error) {
			/* Continue initializing if it's the last try */
			if (retry_cnt < MAX_RETRIES - 1)
				continue;
		}

		/* Wait for Hello packet */
		msleep(BOOT_TIME_DELAY_MS);

		error = elants_i2c_read(client, buf, sizeof(buf));
		if (error) {
			dev_err(&client->dev,
				"failed to read 'hello' packet: %d\n", error);
		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
			ts->iap_mode = ELAN_IAP_OPERATIONAL;
			break;
		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
			/*
			 * Setting error code will mark device
			 * in recovery mode below.
			 */
			error = -EIO;
			break;
		} else {
			error = -EINVAL;
			dev_err(&client->dev,
				"invalid 'hello' packet: %*ph\n",
				(int)sizeof(buf), buf);
		}
	}

	/* hw version is available even if device in recovery state */
	error2 = elants_i2c_query_hw_version(ts);
	if (!error2)
		error2 = elants_i2c_query_bc_version(ts);
	if (!error)
		error = error2;

	if (!error)
		error = elants_i2c_query_fw_version(ts);
	if (!error)
		error = elants_i2c_query_test_version(ts);

	switch (ts->chip_id) {
	case EKTH3500:
		if (!error)
			error = elants_i2c_query_ts_info_ekth(ts);
		break;
	case EKTF3624:
		if (!error)
			error = elants_i2c_query_ts_info_ektf(ts);
		break;
	default:
		BUG();
	}

	if (error)
		ts->iap_mode = ELAN_IAP_RECOVERY;

	return 0;
}

/*
 * Firmware update interface.
 */

static int elants_i2c_fw_write_page(struct i2c_client *client,
				    const void *page)
{
	const u8 ack_ok[] = { 0xaa, 0xaa };
	u8 buf[2];
	int retry;
	int error;

	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
		if (error) {
			dev_err(&client->dev,
				"IAP Write Page failed: %d\n", error);
			continue;
		}

		error = elants_i2c_read(client, buf, 2);
		if (error) {
			dev_err(&client->dev,
				"IAP Ack read failed: %d\n", error);
			return error;
		}

		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
			return 0;

		error = -EIO;
		dev_err(&client->dev,
			"IAP Get Ack Error [%02x:%02x]\n",
			buf[0], buf[1]);
	}

	return error;
}

static int elants_i2c_validate_remark_id(struct elants_data *ts,
					 const struct firmware *fw)
{
	struct i2c_client *client = ts->client;
	int error;
	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
	u8 resp[6] = { 0 };
	u16 ts_remark_id = 0;
	u16 fw_remark_id = 0;

	/* Compare TS Remark ID and FW Remark ID */
	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
					   resp, sizeof(resp),
					   1, "read Remark ID");
	if (error)
		return error;

	ts_remark_id = get_unaligned_be16(&resp[3]);

	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);

	if (fw_remark_id != ts_remark_id) {
		dev_err(&client->dev,
			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
			ts_remark_id, fw_remark_id);
		return -EINVAL;
	}

	return 0;
}

static int elants_i2c_do_update_firmware(struct i2c_client *client,
					 const struct firmware *fw,
					 bool force)
{
	struct elants_data *ts = i2c_get_clientdata(client);
	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
	u8 buf[HEADER_SIZE];
	u16 send_id;
	int page, n_fw_pages;
	int error;
	bool check_remark_id = ts->iap_version >= 0x60;

	/* Recovery mode detection! */
	if (force) {
		dev_dbg(&client->dev, "Recovery mode procedure\n");

		if (check_remark_id) {
			error = elants_i2c_validate_remark_id(ts, fw);
			if (error)
				return error;
		}

		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
		if (error) {
			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
				error);
			return error;
		}
	} else {
		/* Start IAP Procedure */
		dev_dbg(&client->dev, "Normal IAP procedure\n");

		/* Close idle mode */
		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
		if (error)
			dev_err(&client->dev, "Failed close idle: %d\n", error);
		msleep(60);

		elants_i2c_sw_reset(client);
		msleep(20);

		if (check_remark_id) {
			error = elants_i2c_validate_remark_id(ts, fw);
			if (error)
				return error;
		}

		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
		if (error) {
			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
				error);
			return error;
		}
	}

	msleep(20);

	/* check IAP state */
	error = elants_i2c_read(client, buf, 4);
	if (error) {
		dev_err(&client->dev,
			"failed to read IAP acknowledgement: %d\n",
			error);
		return error;
	}

	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
		dev_err(&client->dev,
			"failed to enter IAP: %*ph (expected %*ph)\n",
			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
		return -EIO;
	}

	dev_info(&client->dev, "successfully entered IAP mode");

	send_id = client->addr;
	error = elants_i2c_send(client, &send_id, 1);
	if (error) {
		dev_err(&client->dev, "sending dummy byte failed: %d\n",
			error);
		return error;
	}

	/* Clear the last page of Master */
	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
	if (error) {
		dev_err(&client->dev, "clearing of the last page failed: %d\n",
			error);
		return error;
	}

	error = elants_i2c_read(client, buf, 2);
	if (error) {
		dev_err(&client->dev,
			"failed to read ACK for clearing the last page: %d\n",
			error);
		return error;
	}

	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);

	for (page = 0; page < n_fw_pages; page++) {
		error = elants_i2c_fw_write_page(client,
					fw->data + page * ELAN_FW_PAGESIZE);
		if (error) {
			dev_err(&client->dev,
				"failed to write FW page %d: %d\n",
				page, error);
			return error;
		}
	}

	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
	msleep(300);

	dev_info(&client->dev, "firmware update completed\n");
	return 0;
}

static int elants_i2c_fw_update(struct elants_data *ts)
{
	struct i2c_client *client = ts->client;
	const struct firmware *fw;
	char *fw_name;
	int error;

	fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
	if (!fw_name)
		return -ENOMEM;

	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
	error = request_firmware(&fw, fw_name, &client->dev);
	kfree(fw_name);
	if (error) {
		dev_err(&client->dev, "failed to request firmware: %d\n",
			error);
		return error;
	}

	if (fw->size % ELAN_FW_PAGESIZE) {
		dev_err(&client->dev, "invalid firmware length: %zu\n",
			fw->size);
		error = -EINVAL;
		goto out;
	}

	disable_irq(client->irq);

	error = elants_i2c_do_update_firmware(client, fw,
					ts->iap_mode == ELAN_IAP_RECOVERY);
	if (error) {
		dev_err(&client->dev, "firmware update failed: %d\n", error);
		ts->iap_mode = ELAN_IAP_RECOVERY;
		goto out_enable_irq;
	}

	error = elants_i2c_initialize(ts);
	if (error) {
		dev_err(&client->dev,
			"failed to initialize device after firmware update: %d\n",
			error);
		ts->iap_mode = ELAN_IAP_RECOVERY;
		goto out_enable_irq;
	}

	ts->iap_mode = ELAN_IAP_OPERATIONAL;

out_enable_irq:
	ts->state = ELAN_STATE_NORMAL;
	enable_irq(client->irq);
	msleep(100);

	if (!error)
		elants_i2c_calibrate(ts);
out:
	release_firmware(fw);
	return error;
}

/*
 * Event reporting.
 */

static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf,
				size_t packet_size)
{
	struct input_dev *input = ts->input;
	unsigned int n_fingers;
	unsigned int tool_type;
	u16 finger_state;
	int i;

	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
			buf[FW_POS_STATE];

	dev_dbg(&ts->client->dev,
		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);

	/* Note: all fingers have the same tool type */
	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
			MT_TOOL_FINGER : MT_TOOL_PALM;

	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
		if (finger_state & 1) {
			unsigned int x, y, p, w;
			u8 *pos;

			pos = &buf[FW_POS_XY + i * 3];
			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];

			/*
			 * eKTF3624 may have use "old" touch-report format,
			 * depending on a device and TS firmware version.
			 * For example, ASUS Transformer devices use the "old"
			 * format, while ASUS Nexus 7 uses the "new" formant.
			 */
			if (packet_size == PACKET_SIZE_OLD &&
			    ts->chip_id == EKTF3624) {
				w = buf[FW_POS_WIDTH + i / 2];
				w >>= 4 * (~i & 1);
				w |= w << 4;
				w |= !w;
				p = w;
			} else {
				p = buf[FW_POS_PRESSURE + i];
				w = buf[FW_POS_WIDTH + i];
			}

			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
				i, x, y, p, w);

			input_mt_slot(input, i);
			input_mt_report_slot_state(input, tool_type, true);
			touchscreen_report_pos(input, &ts->prop, x, y, true);
			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);

			n_fingers--;
		}

		finger_state >>= 1;
	}

	input_mt_sync_frame(input);
	input_sync(input);
}

static u8 elants_i2c_calculate_checksum(u8 *buf)
{
	u8 checksum = 0;
	u8 i;

	for (i = 0; i < FW_POS_CHECKSUM; i++)
		checksum += buf[i];

	return checksum;
}

static void elants_i2c_event(struct elants_data *ts, u8 *buf,
			     size_t packet_size)
{
	u8 checksum = elants_i2c_calculate_checksum(buf);

	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
		dev_warn(&ts->client->dev,
			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
			 __func__, buf[FW_POS_HEADER],
			 checksum, buf[FW_POS_CHECKSUM]);
	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
		dev_warn(&ts->client->dev,
			 "%s: unknown packet type: %02x\n",
			 __func__, buf[FW_POS_HEADER]);
	else
		elants_i2c_mt_event(ts, buf, packet_size);
}

static irqreturn_t elants_i2c_irq(int irq, void *_dev)
{
	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
	struct elants_data *ts = _dev;
	struct i2c_client *client = ts->client;
	int report_count, report_len;
	int i;
	int len;

	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
	if (len < 0) {
		dev_err(&client->dev, "%s: failed to read data: %d\n",
			__func__, len);
		goto out;
	}

	dev_dbg(&client->dev, "%s: packet %*ph\n",
		__func__, HEADER_SIZE, ts->buf);

	switch (ts->state) {
	case ELAN_WAIT_RECALIBRATION:
		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
			complete(&ts->cmd_done);
			ts->state = ELAN_STATE_NORMAL;
		}
		break;

	case ELAN_WAIT_QUEUE_HEADER:
		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
			break;

		ts->state = ELAN_STATE_NORMAL;
		fallthrough;

	case ELAN_STATE_NORMAL:

		switch (ts->buf[FW_HDR_TYPE]) {
		case CMD_HEADER_HELLO:
		case CMD_HEADER_RESP:
			break;

		case QUEUE_HEADER_WAIT:
			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
				dev_err(&client->dev,
					"invalid wait packet %*ph\n",
					HEADER_SIZE, ts->buf);
			} else {
				ts->state = ELAN_WAIT_QUEUE_HEADER;
				udelay(30);
			}
			break;

		case QUEUE_HEADER_SINGLE:
			elants_i2c_event(ts, &ts->buf[HEADER_SIZE],
					 ts->buf[FW_HDR_LENGTH]);
			break;

		case QUEUE_HEADER_NORMAL2: /* CMD_HEADER_REK */
			/*
			 * Depending on firmware version, eKTF3624 touchscreens
			 * may utilize one of these opcodes for the touch events:
			 * 0x63 (NORMAL) and 0x66 (NORMAL2).  The 0x63 is used by
			 * older firmware version and differs from 0x66 such that
			 * touch pressure value needs to be adjusted.  The 0x66
			 * opcode of newer firmware is equal to 0x63 of eKTH3500.
			 */
			if (ts->chip_id != EKTF3624)
				break;

			fallthrough;

		case QUEUE_HEADER_NORMAL:
			report_count = ts->buf[FW_HDR_COUNT];
			if (report_count == 0 || report_count > 3) {
				dev_err(&client->dev,
					"bad report count: %*ph\n",
					HEADER_SIZE, ts->buf);
				break;
			}

			report_len = ts->buf[FW_HDR_LENGTH] / report_count;

			if (report_len == PACKET_SIZE_OLD &&
			    ts->chip_id == EKTF3624) {
				dev_dbg_once(&client->dev,
					     "using old report format\n");
			} else if (report_len != PACKET_SIZE) {
				dev_err(&client->dev,
					"mismatching report length: %*ph\n",
					HEADER_SIZE, ts->buf);
				break;
			}

			for (i = 0; i < report_count; i++) {
				u8 *buf = ts->buf + HEADER_SIZE +
							i * report_len;
				elants_i2c_event(ts, buf, report_len);
			}
			break;

		default:
			dev_err(&client->dev, "unknown packet %*ph\n",
				HEADER_SIZE, ts->buf);
			break;
		}
		break;
	}

out:
	return IRQ_HANDLED;
}

/*
 * sysfs interface
 */
static ssize_t calibrate_store(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);
	int error;

	error = mutex_lock_interruptible(&ts->sysfs_mutex);
	if (error)
		return error;

	error = elants_i2c_calibrate(ts);

	mutex_unlock(&ts->sysfs_mutex);
	return error ?: count;
}

static ssize_t write_update_fw(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);
	int error;

	error = mutex_lock_interruptible(&ts->sysfs_mutex);
	if (error)
		return error;

	error = elants_i2c_fw_update(ts);
	dev_dbg(dev, "firmware update result: %d\n", error);

	mutex_unlock(&ts->sysfs_mutex);
	return error ?: count;
}

static ssize_t show_iap_mode(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);

	return sprintf(buf, "%s\n",
		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
				"Normal" : "Recovery");
}

static ssize_t show_calibration_count(struct device *dev,
				      struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
	u8 resp[HEADER_SIZE];
	u16 rek_count;
	int error;

	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
					   resp, sizeof(resp), 1,
					   "read ReK status");
	if (error)
		return sprintf(buf, "%d\n", error);

	rek_count = get_unaligned_be16(&resp[2]);
	return sprintf(buf, "0x%04x\n", rek_count);
}

static DEVICE_ATTR_WO(calibrate);
static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);

struct elants_version_attribute {
	struct device_attribute dattr;
	size_t field_offset;
	size_t field_size;
};

#define __ELANTS_FIELD_SIZE(_field)					\
	sizeof(((struct elants_data *)NULL)->_field)
#define __ELANTS_VERIFY_SIZE(_field)					\
	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
	 __ELANTS_FIELD_SIZE(_field))
#define ELANTS_VERSION_ATTR(_field)					\
	struct elants_version_attribute elants_ver_attr_##_field = {	\
		.dattr = __ATTR(_field, S_IRUGO,			\
				elants_version_attribute_show, NULL),	\
		.field_offset = offsetof(struct elants_data, _field),	\
		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
	}

static ssize_t elants_version_attribute_show(struct device *dev,
					     struct device_attribute *dattr,
					     char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);
	struct elants_version_attribute *attr =
		container_of(dattr, struct elants_version_attribute, dattr);
	u8 *field = (u8 *)((char *)ts + attr->field_offset);
	unsigned int fmt_size;
	unsigned int val;

	if (attr->field_size == 1) {
		val = *field;
		fmt_size = 2; /* 2 HEX digits */
	} else {
		val = *(u16 *)field;
		fmt_size = 4; /* 4 HEX digits */
	}

	return sprintf(buf, "%0*x\n", fmt_size, val);
}

static ELANTS_VERSION_ATTR(fw_version);
static ELANTS_VERSION_ATTR(hw_version);
static ELANTS_VERSION_ATTR(test_version);
static ELANTS_VERSION_ATTR(solution_version);
static ELANTS_VERSION_ATTR(bc_version);
static ELANTS_VERSION_ATTR(iap_version);

static struct attribute *elants_attributes[] = {
	&dev_attr_calibrate.attr,
	&dev_attr_update_fw.attr,
	&dev_attr_iap_mode.attr,
	&dev_attr_calibration_count.attr,

	&elants_ver_attr_fw_version.dattr.attr,
	&elants_ver_attr_hw_version.dattr.attr,
	&elants_ver_attr_test_version.dattr.attr,
	&elants_ver_attr_solution_version.dattr.attr,
	&elants_ver_attr_bc_version.dattr.attr,
	&elants_ver_attr_iap_version.dattr.attr,
	NULL
};

static const struct attribute_group elants_attribute_group = {
	.attrs = elants_attributes,
};

static int elants_i2c_power_on(struct elants_data *ts)
{
	int error;

	/*
	 * If we do not have reset gpio assume platform firmware
	 * controls regulators and does power them on for us.
	 */
	if (IS_ERR_OR_NULL(ts->reset_gpio))
		return 0;

	gpiod_set_value_cansleep(ts->reset_gpio, 1);

	error = regulator_enable(ts->vcc33);
	if (error) {
		dev_err(&ts->client->dev,
			"failed to enable vcc33 regulator: %d\n",
			error);
		goto release_reset_gpio;
	}

	error = regulator_enable(ts->vccio);
	if (error) {
		dev_err(&ts->client->dev,
			"failed to enable vccio regulator: %d\n",
			error);
		regulator_disable(ts->vcc33);
		goto release_reset_gpio;
	}

	/*
	 * We need to wait a bit after powering on controller before
	 * we are allowed to release reset GPIO.
	 */
	udelay(ELAN_POWERON_DELAY_USEC);

release_reset_gpio:
	gpiod_set_value_cansleep(ts->reset_gpio, 0);
	if (error)
		return error;

	msleep(ELAN_RESET_DELAY_MSEC);

	return 0;
}

static void elants_i2c_power_off(void *_data)
{
	struct elants_data *ts = _data;

	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
		/*
		 * Activate reset gpio to prevent leakage through the
		 * pin once we shut off power to the controller.
		 */
		gpiod_set_value_cansleep(ts->reset_gpio, 1);
		regulator_disable(ts->vccio);
		regulator_disable(ts->vcc33);
	}
}

#ifdef CONFIG_ACPI
static const struct acpi_device_id i2c_hid_ids[] = {
	{"ACPI0C50", 0 },
	{"PNP0C50", 0 },
	{ },
};

static const guid_t i2c_hid_guid =
	GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
		  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);

static bool elants_acpi_is_hid_device(struct device *dev)
{
	acpi_handle handle = ACPI_HANDLE(dev);
	union acpi_object *obj;

	if (acpi_match_device_ids(ACPI_COMPANION(dev), i2c_hid_ids))
		return false;

	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, ACPI_TYPE_INTEGER);
	if (obj) {
		ACPI_FREE(obj);
		return true;
	}

	return false;
}
#else
static bool elants_acpi_is_hid_device(struct device *dev)
{
	return false;
}
#endif

static int elants_i2c_probe(struct i2c_client *client,
			    const struct i2c_device_id *id)
{
	union i2c_smbus_data dummy;
	struct elants_data *ts;
	unsigned long irqflags;
	int error;

	/* Don't bind to i2c-hid compatible devices, these are handled by the i2c-hid drv. */
	if (elants_acpi_is_hid_device(&client->dev)) {
		dev_warn(&client->dev, "This device appears to be an I2C-HID device, not binding\n");
		return -ENODEV;
	}

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
		dev_err(&client->dev, "I2C check functionality error\n");
		return -ENXIO;
	}

	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
	if (!ts)
		return -ENOMEM;

	mutex_init(&ts->sysfs_mutex);
	init_completion(&ts->cmd_done);

	ts->client = client;
	ts->chip_id = (enum elants_chip_id)id->driver_data;
	i2c_set_clientdata(client, ts);

	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
	if (IS_ERR(ts->vcc33)) {
		error = PTR_ERR(ts->vcc33);
		if (error != -EPROBE_DEFER)
			dev_err(&client->dev,
				"Failed to get 'vcc33' regulator: %d\n",
				error);
		return error;
	}

	ts->vccio = devm_regulator_get(&client->dev, "vccio");
	if (IS_ERR(ts->vccio)) {
		error = PTR_ERR(ts->vccio);
		if (error != -EPROBE_DEFER)
			dev_err(&client->dev,
				"Failed to get 'vccio' regulator: %d\n",
				error);
		return error;
	}

	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
	if (IS_ERR(ts->reset_gpio)) {
		error = PTR_ERR(ts->reset_gpio);

		if (error == -EPROBE_DEFER)
			return error;

		if (error != -ENOENT && error != -ENOSYS) {
			dev_err(&client->dev,
				"failed to get reset gpio: %d\n",
				error);
			return error;
		}

		ts->keep_power_in_suspend = true;
	}

	error = elants_i2c_power_on(ts);
	if (error)
		return error;

	error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
	if (error) {
		dev_err(&client->dev,
			"failed to install power off action: %d\n", error);
		elants_i2c_power_off(ts);
		return error;
	}

	/* Make sure there is something at this address */
	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
		dev_err(&client->dev, "nothing at this address\n");
		return -ENXIO;
	}

	error = elants_i2c_initialize(ts);
	if (error) {
		dev_err(&client->dev, "failed to initialize: %d\n", error);
		return error;
	}

	ts->input = devm_input_allocate_device(&client->dev);
	if (!ts->input) {
		dev_err(&client->dev, "Failed to allocate input device\n");
		return -ENOMEM;
	}

	ts->input->name = "Elan Touchscreen";
	ts->input->id.bustype = BUS_I2C;

	/* Multitouch input params setup */

	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
			     0, MT_TOOL_PALM, 0, 0);

	touchscreen_parse_properties(ts->input, true, &ts->prop);

	if (ts->chip_id == EKTF3624 && ts->phy_x && ts->phy_y) {
		/* calculate resolution from size */
		ts->x_res = DIV_ROUND_CLOSEST(ts->prop.max_x, ts->phy_x);
		ts->y_res = DIV_ROUND_CLOSEST(ts->prop.max_y, ts->phy_y);
	}

	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
	input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->major_res);

	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
	if (error) {
		dev_err(&client->dev,
			"failed to initialize MT slots: %d\n", error);
		return error;
	}

	error = input_register_device(ts->input);
	if (error) {
		dev_err(&client->dev,
			"unable to register input device: %d\n", error);
		return error;
	}

	/*
	 * Platform code (ACPI, DTS) should normally set up interrupt
	 * for us, but in case it did not let's fall back to using falling
	 * edge to be compatible with older Chromebooks.
	 */
	irqflags = irq_get_trigger_type(client->irq);
	if (!irqflags)
		irqflags = IRQF_TRIGGER_FALLING;

	error = devm_request_threaded_irq(&client->dev, client->irq,
					  NULL, elants_i2c_irq,
					  irqflags | IRQF_ONESHOT,
					  client->name, ts);
	if (error) {
		dev_err(&client->dev, "Failed to register interrupt\n");
		return error;
	}

	/*
	 * Systems using device tree should set up wakeup via DTS,
	 * the rest will configure device as wakeup source by default.
	 */
	if (!client->dev.of_node)
		device_init_wakeup(&client->dev, true);

	error = devm_device_add_group(&client->dev, &elants_attribute_group);
	if (error) {
		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
			error);
		return error;
	}

	return 0;
}

static int __maybe_unused elants_i2c_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);
	const u8 set_sleep_cmd[] = {
		CMD_HEADER_WRITE, E_POWER_STATE_SLEEP, 0x00, 0x01
	};
	int retry_cnt;
	int error;

	/* Command not support in IAP recovery mode */
	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
		return -EBUSY;

	disable_irq(client->irq);

	if (device_may_wakeup(dev)) {
		/*
		 * The device will automatically enter idle mode
		 * that has reduced power consumption.
		 */
		ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
	} else if (ts->keep_power_in_suspend) {
		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
			error = elants_i2c_send(client, set_sleep_cmd,
						sizeof(set_sleep_cmd));
			if (!error)
				break;

			dev_err(&client->dev,
				"suspend command failed: %d\n", error);
		}
	} else {
		elants_i2c_power_off(ts);
	}

	return 0;
}

static int __maybe_unused elants_i2c_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct elants_data *ts = i2c_get_clientdata(client);
	const u8 set_active_cmd[] = {
		CMD_HEADER_WRITE, E_POWER_STATE_RESUME, 0x00, 0x01
	};
	int retry_cnt;
	int error;

	if (device_may_wakeup(dev)) {
		if (ts->wake_irq_enabled)
			disable_irq_wake(client->irq);
		elants_i2c_sw_reset(client);
	} else if (ts->keep_power_in_suspend) {
		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
			error = elants_i2c_send(client, set_active_cmd,
						sizeof(set_active_cmd));
			if (!error)
				break;

			dev_err(&client->dev,
				"resume command failed: %d\n", error);
		}
	} else {
		elants_i2c_power_on(ts);
		elants_i2c_initialize(ts);
	}

	ts->state = ELAN_STATE_NORMAL;
	enable_irq(client->irq);

	return 0;
}

static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
			 elants_i2c_suspend, elants_i2c_resume);

static const struct i2c_device_id elants_i2c_id[] = {
	{ DEVICE_NAME, EKTH3500 },
	{ "ekth3500", EKTH3500 },
	{ "ektf3624", EKTF3624 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, elants_i2c_id);

#ifdef CONFIG_ACPI
static const struct acpi_device_id elants_acpi_id[] = {
	{ "ELAN0001", EKTH3500 },
	{ }
};
MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
#endif

#ifdef CONFIG_OF
static const struct of_device_id elants_of_match[] = {
	{ .compatible = "elan,ekth3500" },
	{ .compatible = "elan,ektf3624" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, elants_of_match);
#endif

static struct i2c_driver elants_i2c_driver = {
	.probe = elants_i2c_probe,
	.id_table = elants_i2c_id,
	.driver = {
		.name = DEVICE_NAME,
		.pm = &elants_i2c_pm_ops,
		.acpi_match_table = ACPI_PTR(elants_acpi_id),
		.of_match_table = of_match_ptr(elants_of_match),
		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
	},
};
module_i2c_driver(elants_i2c_driver);

MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
MODULE_LICENSE("GPL");