summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/rohm_bu21023.c
blob: 730596d599d856ae1d19b83f2ace13034a9eff09 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * ROHM BU21023/24 Dual touch support resistive touch screen driver
 * Copyright (C) 2012 ROHM CO.,LTD.
 */
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/slab.h>

#define BU21023_NAME			"bu21023_ts"
#define BU21023_FIRMWARE_NAME		"bu21023.bin"

#define MAX_CONTACTS			2

#define AXIS_ADJUST			4
#define AXIS_OFFSET			8

#define FIRMWARE_BLOCK_SIZE		32U
#define FIRMWARE_RETRY_MAX		4

#define SAMPLING_DELAY			12	/* msec */

#define CALIBRATION_RETRY_MAX		6

#define ROHM_TS_ABS_X_MIN		40
#define ROHM_TS_ABS_X_MAX		990
#define ROHM_TS_ABS_Y_MIN		160
#define ROHM_TS_ABS_Y_MAX		920
#define ROHM_TS_DISPLACEMENT_MAX	0	/* zero for infinite */

/*
 * BU21023GUL/BU21023MUV/BU21024FV-M registers map
 */
#define VADOUT_YP_H		0x00
#define VADOUT_YP_L		0x01
#define VADOUT_XP_H		0x02
#define VADOUT_XP_L		0x03
#define VADOUT_YN_H		0x04
#define VADOUT_YN_L		0x05
#define VADOUT_XN_H		0x06
#define VADOUT_XN_L		0x07

#define PRM1_X_H		0x08
#define PRM1_X_L		0x09
#define PRM1_Y_H		0x0a
#define PRM1_Y_L		0x0b
#define PRM2_X_H		0x0c
#define PRM2_X_L		0x0d
#define PRM2_Y_H		0x0e
#define PRM2_Y_L		0x0f

#define MLT_PRM_MONI_X		0x10
#define MLT_PRM_MONI_Y		0x11

#define DEBUG_MONI_1		0x12
#define DEBUG_MONI_2		0x13

#define VADOUT_ZX_H		0x14
#define VADOUT_ZX_L		0x15
#define VADOUT_ZY_H		0x16
#define VADOUT_ZY_L		0x17

#define Z_PARAM_H		0x18
#define Z_PARAM_L		0x19

/*
 * Value for VADOUT_*_L
 */
#define VADOUT_L_MASK		0x01

/*
 * Value for PRM*_*_L
 */
#define PRM_L_MASK		0x01

#define POS_X1_H		0x20
#define POS_X1_L		0x21
#define POS_Y1_H		0x22
#define POS_Y1_L		0x23
#define POS_X2_H		0x24
#define POS_X2_L		0x25
#define POS_Y2_H		0x26
#define POS_Y2_L		0x27

/*
 * Value for POS_*_L
 */
#define POS_L_MASK		0x01

#define TOUCH			0x28
#define TOUCH_DETECT		0x01

#define TOUCH_GESTURE		0x29
#define SINGLE_TOUCH		0x01
#define DUAL_TOUCH		0x03
#define TOUCH_MASK		0x03
#define CALIBRATION_REQUEST	0x04
#define CALIBRATION_STATUS	0x08
#define CALIBRATION_MASK	0x0c
#define GESTURE_SPREAD		0x10
#define GESTURE_PINCH		0x20
#define GESTURE_ROTATE_R	0x40
#define GESTURE_ROTATE_L	0x80

#define INT_STATUS		0x2a
#define INT_MASK		0x3d
#define INT_CLEAR		0x3e

/*
 * Values for INT_*
 */
#define COORD_UPDATE		0x01
#define CALIBRATION_DONE	0x02
#define SLEEP_IN		0x04
#define SLEEP_OUT		0x08
#define PROGRAM_LOAD_DONE	0x10
#define ERROR			0x80
#define INT_ALL			0x9f

#define ERR_STATUS		0x2b
#define ERR_MASK		0x3f

/*
 * Values for ERR_*
 */
#define ADC_TIMEOUT		0x01
#define CPU_TIMEOUT		0x02
#define CALIBRATION_ERR		0x04
#define PROGRAM_LOAD_ERR	0x10

#define COMMON_SETUP1			0x30
#define PROGRAM_LOAD_HOST		0x02
#define PROGRAM_LOAD_EEPROM		0x03
#define CENSOR_4PORT			0x04
#define CENSOR_8PORT			0x00	/* Not supported by BU21023 */
#define CALIBRATION_TYPE_DEFAULT	0x08
#define CALIBRATION_TYPE_SPECIAL	0x00
#define INT_ACTIVE_HIGH			0x10
#define INT_ACTIVE_LOW			0x00
#define AUTO_CALIBRATION		0x40
#define MANUAL_CALIBRATION		0x00
#define COMMON_SETUP1_DEFAULT		0x4e

#define COMMON_SETUP2		0x31
#define MAF_NONE		0x00
#define MAF_1SAMPLE		0x01
#define MAF_3SAMPLES		0x02
#define MAF_5SAMPLES		0x03
#define INV_Y			0x04
#define INV_X			0x08
#define SWAP_XY			0x10

#define COMMON_SETUP3		0x32
#define EN_SLEEP		0x01
#define EN_MULTI		0x02
#define EN_GESTURE		0x04
#define EN_INTVL		0x08
#define SEL_STEP		0x10
#define SEL_MULTI		0x20
#define SEL_TBL_DEFAULT		0x40

#define INTERVAL_TIME		0x33
#define INTERVAL_TIME_DEFAULT	0x10

#define STEP_X			0x34
#define STEP_X_DEFAULT		0x41

#define STEP_Y			0x35
#define STEP_Y_DEFAULT		0x8d

#define OFFSET_X		0x38
#define OFFSET_X_DEFAULT	0x0c

#define OFFSET_Y		0x39
#define OFFSET_Y_DEFAULT	0x0c

#define THRESHOLD_TOUCH		0x3a
#define THRESHOLD_TOUCH_DEFAULT	0xa0

#define THRESHOLD_GESTURE		0x3b
#define THRESHOLD_GESTURE_DEFAULT	0x17

#define SYSTEM			0x40
#define ANALOG_POWER_ON		0x01
#define ANALOG_POWER_OFF	0x00
#define CPU_POWER_ON		0x02
#define CPU_POWER_OFF		0x00

#define FORCE_CALIBRATION	0x42
#define FORCE_CALIBRATION_ON	0x01
#define FORCE_CALIBRATION_OFF	0x00

#define CPU_FREQ		0x50	/* 10 / (reg + 1) MHz */
#define CPU_FREQ_10MHZ		0x00
#define CPU_FREQ_5MHZ		0x01
#define CPU_FREQ_1MHZ		0x09

#define EEPROM_ADDR		0x51

#define CALIBRATION_ADJUST		0x52
#define CALIBRATION_ADJUST_DEFAULT	0x00

#define THRESHOLD_SLEEP_IN	0x53

#define EVR_XY			0x56
#define EVR_XY_DEFAULT		0x10

#define PRM_SWOFF_TIME		0x57
#define PRM_SWOFF_TIME_DEFAULT	0x04

#define PROGRAM_VERSION		0x5f

#define ADC_CTRL		0x60
#define ADC_DIV_MASK		0x1f	/* The minimum value is 4 */
#define ADC_DIV_DEFAULT		0x08

#define ADC_WAIT		0x61
#define ADC_WAIT_DEFAULT	0x0a

#define SWCONT			0x62
#define SWCONT_DEFAULT		0x0f

#define EVR_X			0x63
#define EVR_X_DEFAULT		0x86

#define EVR_Y			0x64
#define EVR_Y_DEFAULT		0x64

#define TEST1			0x65
#define DUALTOUCH_STABILIZE_ON	0x01
#define DUALTOUCH_STABILIZE_OFF	0x00
#define DUALTOUCH_REG_ON	0x20
#define DUALTOUCH_REG_OFF	0x00

#define CALIBRATION_REG1		0x68
#define CALIBRATION_REG1_DEFAULT	0xd9

#define CALIBRATION_REG2		0x69
#define CALIBRATION_REG2_DEFAULT	0x36

#define CALIBRATION_REG3		0x6a
#define CALIBRATION_REG3_DEFAULT	0x32

#define EX_ADDR_H		0x70
#define EX_ADDR_L		0x71
#define EX_WDAT			0x72
#define EX_RDAT			0x73
#define EX_CHK_SUM1		0x74
#define EX_CHK_SUM2		0x75
#define EX_CHK_SUM3		0x76

struct rohm_ts_data {
	struct i2c_client *client;
	struct input_dev *input;

	bool initialized;

	unsigned int contact_count[MAX_CONTACTS + 1];
	int finger_count;

	u8 setup2;
};

/*
 * rohm_i2c_burst_read - execute combined I2C message for ROHM BU21023/24
 * @client: Handle to ROHM BU21023/24
 * @start: Where to start read address from ROHM BU21023/24
 * @buf: Where to store read data from ROHM BU21023/24
 * @len: How many bytes to read
 *
 * Returns negative errno, else zero on success.
 *
 * Note
 * In BU21023/24 burst read, stop condition is needed after "address write".
 * Therefore, transmission is performed in 2 steps.
 */
static int rohm_i2c_burst_read(struct i2c_client *client, u8 start, void *buf,
			       size_t len)
{
	struct i2c_adapter *adap = client->adapter;
	struct i2c_msg msg[2];
	int i, ret = 0;

	msg[0].addr = client->addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = &start;

	msg[1].addr = client->addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = len;
	msg[1].buf = buf;

	i2c_lock_bus(adap, I2C_LOCK_SEGMENT);

	for (i = 0; i < 2; i++) {
		if (__i2c_transfer(adap, &msg[i], 1) < 0) {
			ret = -EIO;
			break;
		}
	}

	i2c_unlock_bus(adap, I2C_LOCK_SEGMENT);

	return ret;
}

static int rohm_ts_manual_calibration(struct rohm_ts_data *ts)
{
	struct i2c_client *client = ts->client;
	struct device *dev = &client->dev;
	u8 buf[33];	/* for PRM1_X_H(0x08)-TOUCH(0x28) */

	int retry;
	bool success = false;
	bool first_time = true;
	bool calibration_done;

	u8 reg1, reg2, reg3;
	s32 reg1_orig, reg2_orig, reg3_orig;
	s32 val;

	int calib_x = 0, calib_y = 0;
	int reg_x, reg_y;
	int err_x, err_y;

	int error, error2;
	int i;

	reg1_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG1);
	if (reg1_orig < 0)
		return reg1_orig;

	reg2_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG2);
	if (reg2_orig < 0)
		return reg2_orig;

	reg3_orig = i2c_smbus_read_byte_data(client, CALIBRATION_REG3);
	if (reg3_orig < 0)
		return reg3_orig;

	error = i2c_smbus_write_byte_data(client, INT_MASK,
					  COORD_UPDATE | SLEEP_IN | SLEEP_OUT |
					  PROGRAM_LOAD_DONE);
	if (error)
		goto out;

	error = i2c_smbus_write_byte_data(client, TEST1,
					  DUALTOUCH_STABILIZE_ON);
	if (error)
		goto out;

	for (retry = 0; retry < CALIBRATION_RETRY_MAX; retry++) {
		/* wait 2 sampling for update */
		mdelay(2 * SAMPLING_DELAY);

#define READ_CALIB_BUF(reg)	buf[((reg) - PRM1_X_H)]

		error = rohm_i2c_burst_read(client, PRM1_X_H, buf, sizeof(buf));
		if (error)
			goto out;

		if (READ_CALIB_BUF(TOUCH) & TOUCH_DETECT)
			continue;

		if (first_time) {
			/* generate calibration parameter */
			calib_x = ((int)READ_CALIB_BUF(PRM1_X_H) << 2 |
				READ_CALIB_BUF(PRM1_X_L)) - AXIS_OFFSET;
			calib_y = ((int)READ_CALIB_BUF(PRM1_Y_H) << 2 |
				READ_CALIB_BUF(PRM1_Y_L)) - AXIS_OFFSET;

			error = i2c_smbus_write_byte_data(client, TEST1,
				DUALTOUCH_STABILIZE_ON | DUALTOUCH_REG_ON);
			if (error)
				goto out;

			first_time = false;
		} else {
			/* generate adjustment parameter */
			err_x = (int)READ_CALIB_BUF(PRM1_X_H) << 2 |
				READ_CALIB_BUF(PRM1_X_L);
			err_y = (int)READ_CALIB_BUF(PRM1_Y_H) << 2 |
				READ_CALIB_BUF(PRM1_Y_L);

			/* X axis ajust */
			if (err_x <= 4)
				calib_x -= AXIS_ADJUST;
			else if (err_x >= 60)
				calib_x += AXIS_ADJUST;

			/* Y axis ajust */
			if (err_y <= 4)
				calib_y -= AXIS_ADJUST;
			else if (err_y >= 60)
				calib_y += AXIS_ADJUST;
		}

		/* generate calibration setting value */
		reg_x = calib_x + ((calib_x & 0x200) << 1);
		reg_y = calib_y + ((calib_y & 0x200) << 1);

		/* convert for register format */
		reg1 = reg_x >> 3;
		reg2 = (reg_y & 0x7) << 4 | (reg_x & 0x7);
		reg3 = reg_y >> 3;

		error = i2c_smbus_write_byte_data(client,
						  CALIBRATION_REG1, reg1);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client,
						  CALIBRATION_REG2, reg2);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client,
						  CALIBRATION_REG3, reg3);
		if (error)
			goto out;

		/*
		 * force calibration sequcence
		 */
		error = i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
						  FORCE_CALIBRATION_OFF);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
						  FORCE_CALIBRATION_ON);
		if (error)
			goto out;

		/* clear all interrupts */
		error = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
		if (error)
			goto out;

		/*
		 * Wait for the status change of calibration, max 10 sampling
		 */
		calibration_done = false;

		for (i = 0; i < 10; i++) {
			mdelay(SAMPLING_DELAY);

			val = i2c_smbus_read_byte_data(client, TOUCH_GESTURE);
			if (!(val & CALIBRATION_MASK)) {
				calibration_done = true;
				break;
			} else if (val < 0) {
				error = val;
				goto out;
			}
		}

		if (calibration_done) {
			val = i2c_smbus_read_byte_data(client, INT_STATUS);
			if (val == CALIBRATION_DONE) {
				success = true;
				break;
			} else if (val < 0) {
				error = val;
				goto out;
			}
		} else {
			dev_warn(dev, "calibration timeout\n");
		}
	}

	if (!success) {
		error = i2c_smbus_write_byte_data(client, CALIBRATION_REG1,
						  reg1_orig);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client, CALIBRATION_REG2,
						  reg2_orig);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client, CALIBRATION_REG3,
						  reg3_orig);
		if (error)
			goto out;

		/* calibration data enable */
		error = i2c_smbus_write_byte_data(client, TEST1,
						  DUALTOUCH_STABILIZE_ON |
						  DUALTOUCH_REG_ON);
		if (error)
			goto out;

		/* wait 10 sampling */
		mdelay(10 * SAMPLING_DELAY);

		error = -EBUSY;
	}

out:
	error2 = i2c_smbus_write_byte_data(client, INT_MASK, INT_ALL);
	if (!error2)
		/* Clear all interrupts */
		error2 = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);

	return error ? error : error2;
}

static const unsigned int untouch_threshold[3] = { 0, 1, 5 };
static const unsigned int single_touch_threshold[3] = { 0, 0, 4 };
static const unsigned int dual_touch_threshold[3] = { 10, 8, 0 };

static irqreturn_t rohm_ts_soft_irq(int irq, void *dev_id)
{
	struct rohm_ts_data *ts = dev_id;
	struct i2c_client *client = ts->client;
	struct input_dev *input_dev = ts->input;
	struct device *dev = &client->dev;

	u8 buf[10];	/* for POS_X1_H(0x20)-TOUCH_GESTURE(0x29) */

	struct input_mt_pos pos[MAX_CONTACTS];
	int slots[MAX_CONTACTS];
	u8 touch_flags;
	unsigned int threshold;
	int finger_count = -1;
	int prev_finger_count = ts->finger_count;
	int count;
	int error;
	int i;

	error = i2c_smbus_write_byte_data(client, INT_MASK, INT_ALL);
	if (error)
		return IRQ_HANDLED;

	/* Clear all interrupts */
	error = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
	if (error)
		return IRQ_HANDLED;

#define READ_POS_BUF(reg)	buf[((reg) - POS_X1_H)]

	error = rohm_i2c_burst_read(client, POS_X1_H, buf, sizeof(buf));
	if (error)
		return IRQ_HANDLED;

	touch_flags = READ_POS_BUF(TOUCH_GESTURE) & TOUCH_MASK;
	if (touch_flags) {
		/* generate coordinates */
		pos[0].x = ((s16)READ_POS_BUF(POS_X1_H) << 2) |
			   READ_POS_BUF(POS_X1_L);
		pos[0].y = ((s16)READ_POS_BUF(POS_Y1_H) << 2) |
			   READ_POS_BUF(POS_Y1_L);
		pos[1].x = ((s16)READ_POS_BUF(POS_X2_H) << 2) |
			   READ_POS_BUF(POS_X2_L);
		pos[1].y = ((s16)READ_POS_BUF(POS_Y2_H) << 2) |
			   READ_POS_BUF(POS_Y2_L);
	}

	switch (touch_flags) {
	case 0:
		threshold = untouch_threshold[prev_finger_count];
		if (++ts->contact_count[0] >= threshold)
			finger_count = 0;
		break;

	case SINGLE_TOUCH:
		threshold = single_touch_threshold[prev_finger_count];
		if (++ts->contact_count[1] >= threshold)
			finger_count = 1;

		if (finger_count == 1) {
			if (pos[1].x != 0 && pos[1].y != 0) {
				pos[0].x = pos[1].x;
				pos[0].y = pos[1].y;
				pos[1].x = 0;
				pos[1].y = 0;
			}
		}
		break;

	case DUAL_TOUCH:
		threshold = dual_touch_threshold[prev_finger_count];
		if (++ts->contact_count[2] >= threshold)
			finger_count = 2;
		break;

	default:
		dev_dbg(dev,
			"Three or more touches are not supported\n");
		return IRQ_HANDLED;
	}

	if (finger_count >= 0) {
		if (prev_finger_count != finger_count) {
			count = ts->contact_count[finger_count];
			memset(ts->contact_count, 0, sizeof(ts->contact_count));
			ts->contact_count[finger_count] = count;
		}

		input_mt_assign_slots(input_dev, slots, pos,
				      finger_count, ROHM_TS_DISPLACEMENT_MAX);

		for (i = 0; i < finger_count; i++) {
			input_mt_slot(input_dev, slots[i]);
			input_mt_report_slot_state(input_dev,
						   MT_TOOL_FINGER, true);
			input_report_abs(input_dev,
					 ABS_MT_POSITION_X, pos[i].x);
			input_report_abs(input_dev,
					 ABS_MT_POSITION_Y, pos[i].y);
		}

		input_mt_sync_frame(input_dev);
		input_mt_report_pointer_emulation(input_dev, true);
		input_sync(input_dev);

		ts->finger_count = finger_count;
	}

	if (READ_POS_BUF(TOUCH_GESTURE) & CALIBRATION_REQUEST) {
		error = rohm_ts_manual_calibration(ts);
		if (error)
			dev_warn(dev, "manual calibration failed: %d\n",
				 error);
	}

	i2c_smbus_write_byte_data(client, INT_MASK,
				  CALIBRATION_DONE | SLEEP_OUT | SLEEP_IN |
				  PROGRAM_LOAD_DONE);

	return IRQ_HANDLED;
}

static int rohm_ts_load_firmware(struct i2c_client *client,
				 const char *firmware_name)
{
	struct device *dev = &client->dev;
	const struct firmware *fw;
	s32 status;
	unsigned int offset, len, xfer_len;
	unsigned int retry = 0;
	int error, error2;

	error = request_firmware(&fw, firmware_name, dev);
	if (error) {
		dev_err(dev, "unable to retrieve firmware %s: %d\n",
			firmware_name, error);
		return error;
	}

	error = i2c_smbus_write_byte_data(client, INT_MASK,
					  COORD_UPDATE | CALIBRATION_DONE |
					  SLEEP_IN | SLEEP_OUT);
	if (error)
		goto out;

	do {
		if (retry) {
			dev_warn(dev, "retrying firmware load\n");

			/* settings for retry */
			error = i2c_smbus_write_byte_data(client, EX_WDAT, 0);
			if (error)
				goto out;
		}

		error = i2c_smbus_write_byte_data(client, EX_ADDR_H, 0);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client, EX_ADDR_L, 0);
		if (error)
			goto out;

		error = i2c_smbus_write_byte_data(client, COMMON_SETUP1,
						  COMMON_SETUP1_DEFAULT);
		if (error)
			goto out;

		/* firmware load to the device */
		offset = 0;
		len = fw->size;

		while (len) {
			xfer_len = min(FIRMWARE_BLOCK_SIZE, len);

			error = i2c_smbus_write_i2c_block_data(client, EX_WDAT,
						xfer_len, &fw->data[offset]);
			if (error)
				goto out;

			len -= xfer_len;
			offset += xfer_len;
		}

		/* check firmware load result */
		status = i2c_smbus_read_byte_data(client, INT_STATUS);
		if (status < 0) {
			error = status;
			goto out;
		}

		/* clear all interrupts */
		error = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
		if (error)
			goto out;

		if (status == PROGRAM_LOAD_DONE)
			break;

		error = -EIO;
	} while (++retry <= FIRMWARE_RETRY_MAX);

out:
	error2 = i2c_smbus_write_byte_data(client, INT_MASK, INT_ALL);

	release_firmware(fw);

	return error ? error : error2;
}

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

	return sprintf(buf, "%d\n", !!(ts->setup2 & SWAP_XY));
}

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

	error = kstrtouint(buf, 0, &val);
	if (error)
		return error;

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

	if (val)
		ts->setup2 |= SWAP_XY;
	else
		ts->setup2 &= ~SWAP_XY;

	if (ts->initialized)
		error = i2c_smbus_write_byte_data(ts->client, COMMON_SETUP2,
						  ts->setup2);

	mutex_unlock(&ts->input->mutex);

	return error ? error : count;
}

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

	return sprintf(buf, "%d\n", !!(ts->setup2 & INV_X));
}

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

	error = kstrtouint(buf, 0, &val);
	if (error)
		return error;

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

	if (val)
		ts->setup2 |= INV_X;
	else
		ts->setup2 &= ~INV_X;

	if (ts->initialized)
		error = i2c_smbus_write_byte_data(ts->client, COMMON_SETUP2,
						  ts->setup2);

	mutex_unlock(&ts->input->mutex);

	return error ? error : count;
}

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

	return sprintf(buf, "%d\n", !!(ts->setup2 & INV_Y));
}

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

	error = kstrtouint(buf, 0, &val);
	if (error)
		return error;

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

	if (val)
		ts->setup2 |= INV_Y;
	else
		ts->setup2 &= ~INV_Y;

	if (ts->initialized)
		error = i2c_smbus_write_byte_data(client, COMMON_SETUP2,
						  ts->setup2);

	mutex_unlock(&ts->input->mutex);

	return error ? error : count;
}

static DEVICE_ATTR_RW(swap_xy);
static DEVICE_ATTR_RW(inv_x);
static DEVICE_ATTR_RW(inv_y);

static struct attribute *rohm_ts_attrs[] = {
	&dev_attr_swap_xy.attr,
	&dev_attr_inv_x.attr,
	&dev_attr_inv_y.attr,
	NULL,
};

static const struct attribute_group rohm_ts_attr_group = {
	.attrs = rohm_ts_attrs,
};

static int rohm_ts_device_init(struct i2c_client *client, u8 setup2)
{
	struct device *dev = &client->dev;
	int error;

	disable_irq(client->irq);

	/*
	 * Wait 200usec for reset
	 */
	udelay(200);

	/* Release analog reset */
	error = i2c_smbus_write_byte_data(client, SYSTEM,
					  ANALOG_POWER_ON | CPU_POWER_OFF);
	if (error)
		return error;

	/* Waiting for the analog warm-up, max. 200usec */
	udelay(200);

	/* clear all interrupts */
	error = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, EX_WDAT, 0);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, COMMON_SETUP1, 0);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, COMMON_SETUP2, setup2);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, COMMON_SETUP3,
					  SEL_TBL_DEFAULT | EN_MULTI);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, THRESHOLD_GESTURE,
					  THRESHOLD_GESTURE_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, INTERVAL_TIME,
					  INTERVAL_TIME_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, CPU_FREQ, CPU_FREQ_10MHZ);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, PRM_SWOFF_TIME,
					  PRM_SWOFF_TIME_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, ADC_CTRL, ADC_DIV_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, ADC_WAIT, ADC_WAIT_DEFAULT);
	if (error)
		return error;

	/*
	 * Panel setup, these values change with the panel.
	 */
	error = i2c_smbus_write_byte_data(client, STEP_X, STEP_X_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, STEP_Y, STEP_Y_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, OFFSET_X, OFFSET_X_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, OFFSET_Y, OFFSET_Y_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, THRESHOLD_TOUCH,
					  THRESHOLD_TOUCH_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, EVR_XY, EVR_XY_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, EVR_X, EVR_X_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, EVR_Y, EVR_Y_DEFAULT);
	if (error)
		return error;

	/* Fixed value settings */
	error = i2c_smbus_write_byte_data(client, CALIBRATION_ADJUST,
					  CALIBRATION_ADJUST_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, SWCONT, SWCONT_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, TEST1,
					  DUALTOUCH_STABILIZE_ON |
					  DUALTOUCH_REG_ON);
	if (error)
		return error;

	error = rohm_ts_load_firmware(client, BU21023_FIRMWARE_NAME);
	if (error) {
		dev_err(dev, "failed to load firmware: %d\n", error);
		return error;
	}

	/*
	 * Manual calibration results are not changed in same environment.
	 * If the force calibration is performed,
	 * the controller will not require calibration request interrupt
	 * when the typical values are set to the calibration registers.
	 */
	error = i2c_smbus_write_byte_data(client, CALIBRATION_REG1,
					  CALIBRATION_REG1_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, CALIBRATION_REG2,
					  CALIBRATION_REG2_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, CALIBRATION_REG3,
					  CALIBRATION_REG3_DEFAULT);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
					  FORCE_CALIBRATION_OFF);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, FORCE_CALIBRATION,
					  FORCE_CALIBRATION_ON);
	if (error)
		return error;

	/* Clear all interrupts */
	error = i2c_smbus_write_byte_data(client, INT_CLEAR, 0xff);
	if (error)
		return error;

	/* Enable coordinates update interrupt */
	error = i2c_smbus_write_byte_data(client, INT_MASK,
					  CALIBRATION_DONE | SLEEP_OUT |
					  SLEEP_IN | PROGRAM_LOAD_DONE);
	if (error)
		return error;

	error = i2c_smbus_write_byte_data(client, ERR_MASK,
					  PROGRAM_LOAD_ERR | CPU_TIMEOUT |
					  ADC_TIMEOUT);
	if (error)
		return error;

	/* controller CPU power on */
	error = i2c_smbus_write_byte_data(client, SYSTEM,
					  ANALOG_POWER_ON | CPU_POWER_ON);

	enable_irq(client->irq);

	return error;
}

static int rohm_ts_power_off(struct i2c_client *client)
{
	int error;

	error = i2c_smbus_write_byte_data(client, SYSTEM,
					  ANALOG_POWER_ON | CPU_POWER_OFF);
	if (error) {
		dev_err(&client->dev,
			"failed to power off device CPU: %d\n", error);
		return error;
	}

	error = i2c_smbus_write_byte_data(client, SYSTEM,
					  ANALOG_POWER_OFF | CPU_POWER_OFF);
	if (error)
		dev_err(&client->dev,
			"failed to power off the device: %d\n", error);

	return error;
}

static int rohm_ts_open(struct input_dev *input_dev)
{
	struct rohm_ts_data *ts = input_get_drvdata(input_dev);
	struct i2c_client *client = ts->client;
	int error;

	if (!ts->initialized) {
		error = rohm_ts_device_init(client, ts->setup2);
		if (error) {
			dev_err(&client->dev,
				"device initialization failed: %d\n", error);
			return error;
		}

		ts->initialized = true;
	}

	return 0;
}

static void rohm_ts_close(struct input_dev *input_dev)
{
	struct rohm_ts_data *ts = input_get_drvdata(input_dev);

	rohm_ts_power_off(ts->client);

	ts->initialized = false;
}

static int rohm_bu21023_i2c_probe(struct i2c_client *client,
				  const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct rohm_ts_data *ts;
	struct input_dev *input;
	int error;

	if (!client->irq) {
		dev_err(dev, "IRQ is not assigned\n");
		return -EINVAL;
	}

	if (!client->adapter->algo->master_xfer) {
		dev_err(dev, "I2C level transfers not supported\n");
		return -EOPNOTSUPP;
	}

	/* Turn off CPU just in case */
	error = rohm_ts_power_off(client);
	if (error)
		return error;

	ts = devm_kzalloc(dev, sizeof(struct rohm_ts_data), GFP_KERNEL);
	if (!ts)
		return -ENOMEM;

	ts->client = client;
	ts->setup2 = MAF_1SAMPLE;
	i2c_set_clientdata(client, ts);

	input = devm_input_allocate_device(dev);
	if (!input)
		return -ENOMEM;

	input->name = BU21023_NAME;
	input->id.bustype = BUS_I2C;
	input->open = rohm_ts_open;
	input->close = rohm_ts_close;

	ts->input = input;
	input_set_drvdata(input, ts);

	input_set_abs_params(input, ABS_MT_POSITION_X,
			     ROHM_TS_ABS_X_MIN, ROHM_TS_ABS_X_MAX, 0, 0);
	input_set_abs_params(input, ABS_MT_POSITION_Y,
			     ROHM_TS_ABS_Y_MIN, ROHM_TS_ABS_Y_MAX, 0, 0);

	error = input_mt_init_slots(input, MAX_CONTACTS,
				    INPUT_MT_DIRECT | INPUT_MT_TRACK |
				    INPUT_MT_DROP_UNUSED);
	if (error) {
		dev_err(dev, "failed to multi touch slots initialization\n");
		return error;
	}

	error = devm_request_threaded_irq(dev, client->irq,
					  NULL, rohm_ts_soft_irq,
					  IRQF_ONESHOT, client->name, ts);
	if (error) {
		dev_err(dev, "failed to request IRQ: %d\n", error);
		return error;
	}

	error = input_register_device(input);
	if (error) {
		dev_err(dev, "failed to register input device: %d\n", error);
		return error;
	}

	error = devm_device_add_group(dev, &rohm_ts_attr_group);
	if (error) {
		dev_err(dev, "failed to create sysfs group: %d\n", error);
		return error;
	}

	return error;
}

static const struct i2c_device_id rohm_bu21023_i2c_id[] = {
	{ BU21023_NAME, 0 },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, rohm_bu21023_i2c_id);

static struct i2c_driver rohm_bu21023_i2c_driver = {
	.driver = {
		.name = BU21023_NAME,
	},
	.probe = rohm_bu21023_i2c_probe,
	.id_table = rohm_bu21023_i2c_id,
};
module_i2c_driver(rohm_bu21023_i2c_driver);

MODULE_DESCRIPTION("ROHM BU21023/24 Touchscreen driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("ROHM Co., Ltd.");