summaryrefslogtreecommitdiff
path: root/drivers/iio/accel/bma400_core.c
blob: 89db242f06e0bed46a54f24390073addda63a7ce (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
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Core IIO driver for Bosch BMA400 triaxial acceleration sensor.
 *
 * Copyright 2019 Dan Robertson <dan@dlrobertson.com>
 *
 * TODO:
 *  - Support for power management
 *  - Support events and interrupts
 *  - Create channel for step count
 *  - Create channel for sensor time
 */

#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/cleanup.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>

#include <asm/unaligned.h>

#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/events.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>

#include "bma400.h"

/*
 * The G-range selection may be one of 2g, 4g, 8, or 16g. The scale may
 * be selected with the acc_range bits of the ACC_CONFIG1 register.
 * NB: This buffer is populated in the device init.
 */
static int bma400_scales[8];

/*
 * See the ACC_CONFIG1 section of the datasheet.
 * NB: This buffer is populated in the device init.
 */
static int bma400_sample_freqs[14];

static const int bma400_osr_range[] = { 0, 1, 3 };

static int tap_reset_timeout[BMA400_TAP_TIM_LIST_LEN] = {
	300000,
	400000,
	500000,
	600000
};

static int tap_max2min_time[BMA400_TAP_TIM_LIST_LEN] = {
	30000,
	45000,
	60000,
	90000
};

static int double_tap2_min_delay[BMA400_TAP_TIM_LIST_LEN] = {
	20000,
	40000,
	60000,
	80000
};

/* See the ACC_CONFIG0 section of the datasheet */
enum bma400_power_mode {
	POWER_MODE_SLEEP   = 0x00,
	POWER_MODE_LOW     = 0x01,
	POWER_MODE_NORMAL  = 0x02,
	POWER_MODE_INVALID = 0x03,
};

enum bma400_scan {
	BMA400_ACCL_X,
	BMA400_ACCL_Y,
	BMA400_ACCL_Z,
	BMA400_TEMP,
};

struct bma400_sample_freq {
	int hz;
	int uhz;
};

enum bma400_activity {
	BMA400_STILL,
	BMA400_WALKING,
	BMA400_RUNNING,
};

struct bma400_data {
	struct device *dev;
	struct regmap *regmap;
	struct mutex mutex; /* data register lock */
	struct iio_mount_matrix orientation;
	enum bma400_power_mode power_mode;
	struct bma400_sample_freq sample_freq;
	int oversampling_ratio;
	int scale;
	struct iio_trigger *trig;
	int steps_enabled;
	bool step_event_en;
	bool activity_event_en;
	unsigned int generic_event_en;
	unsigned int tap_event_en_bitmask;
	/* Correct time stamp alignment */
	struct {
		__le16 buff[3];
		u8 temperature;
		s64 ts __aligned(8);
	} buffer __aligned(IIO_DMA_MINALIGN);
	__le16 status;
	__be16 duration;
};

static bool bma400_is_writable_reg(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case BMA400_CHIP_ID_REG:
	case BMA400_ERR_REG:
	case BMA400_STATUS_REG:
	case BMA400_X_AXIS_LSB_REG:
	case BMA400_X_AXIS_MSB_REG:
	case BMA400_Y_AXIS_LSB_REG:
	case BMA400_Y_AXIS_MSB_REG:
	case BMA400_Z_AXIS_LSB_REG:
	case BMA400_Z_AXIS_MSB_REG:
	case BMA400_SENSOR_TIME0:
	case BMA400_SENSOR_TIME1:
	case BMA400_SENSOR_TIME2:
	case BMA400_EVENT_REG:
	case BMA400_INT_STAT0_REG:
	case BMA400_INT_STAT1_REG:
	case BMA400_INT_STAT2_REG:
	case BMA400_TEMP_DATA_REG:
	case BMA400_FIFO_LENGTH0_REG:
	case BMA400_FIFO_LENGTH1_REG:
	case BMA400_FIFO_DATA_REG:
	case BMA400_STEP_CNT0_REG:
	case BMA400_STEP_CNT1_REG:
	case BMA400_STEP_CNT3_REG:
	case BMA400_STEP_STAT_REG:
		return false;
	default:
		return true;
	}
}

static bool bma400_is_volatile_reg(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case BMA400_ERR_REG:
	case BMA400_STATUS_REG:
	case BMA400_X_AXIS_LSB_REG:
	case BMA400_X_AXIS_MSB_REG:
	case BMA400_Y_AXIS_LSB_REG:
	case BMA400_Y_AXIS_MSB_REG:
	case BMA400_Z_AXIS_LSB_REG:
	case BMA400_Z_AXIS_MSB_REG:
	case BMA400_SENSOR_TIME0:
	case BMA400_SENSOR_TIME1:
	case BMA400_SENSOR_TIME2:
	case BMA400_EVENT_REG:
	case BMA400_INT_STAT0_REG:
	case BMA400_INT_STAT1_REG:
	case BMA400_INT_STAT2_REG:
	case BMA400_TEMP_DATA_REG:
	case BMA400_FIFO_LENGTH0_REG:
	case BMA400_FIFO_LENGTH1_REG:
	case BMA400_FIFO_DATA_REG:
	case BMA400_STEP_CNT0_REG:
	case BMA400_STEP_CNT1_REG:
	case BMA400_STEP_CNT3_REG:
	case BMA400_STEP_STAT_REG:
		return true;
	default:
		return false;
	}
}

const struct regmap_config bma400_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = BMA400_CMD_REG,
	.cache_type = REGCACHE_RBTREE,
	.writeable_reg = bma400_is_writable_reg,
	.volatile_reg = bma400_is_volatile_reg,
};
EXPORT_SYMBOL_NS(bma400_regmap_config, IIO_BMA400);

static const struct iio_mount_matrix *
bma400_accel_get_mount_matrix(const struct iio_dev *indio_dev,
			      const struct iio_chan_spec *chan)
{
	struct bma400_data *data = iio_priv(indio_dev);

	return &data->orientation;
}

static const struct iio_chan_spec_ext_info bma400_ext_info[] = {
	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bma400_accel_get_mount_matrix),
	{ }
};

static const struct iio_event_spec bma400_step_detect_event = {
	.type = IIO_EV_TYPE_CHANGE,
	.dir = IIO_EV_DIR_NONE,
	.mask_separate = BIT(IIO_EV_INFO_ENABLE),
};

static const struct iio_event_spec bma400_activity_event = {
	.type = IIO_EV_TYPE_CHANGE,
	.dir = IIO_EV_DIR_NONE,
	.mask_shared_by_type = BIT(IIO_EV_INFO_ENABLE),
};

static const struct iio_event_spec bma400_accel_event[] = {
	{
		.type = IIO_EV_TYPE_MAG,
		.dir = IIO_EV_DIR_FALLING,
		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
				       BIT(IIO_EV_INFO_PERIOD) |
				       BIT(IIO_EV_INFO_HYSTERESIS) |
				       BIT(IIO_EV_INFO_ENABLE),
	},
	{
		.type = IIO_EV_TYPE_MAG,
		.dir = IIO_EV_DIR_RISING,
		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
				       BIT(IIO_EV_INFO_PERIOD) |
				       BIT(IIO_EV_INFO_HYSTERESIS) |
				       BIT(IIO_EV_INFO_ENABLE),
	},
	{
		.type = IIO_EV_TYPE_GESTURE,
		.dir = IIO_EV_DIR_SINGLETAP,
		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
				       BIT(IIO_EV_INFO_ENABLE) |
				       BIT(IIO_EV_INFO_RESET_TIMEOUT),
	},
	{
		.type = IIO_EV_TYPE_GESTURE,
		.dir = IIO_EV_DIR_DOUBLETAP,
		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
				       BIT(IIO_EV_INFO_ENABLE) |
				       BIT(IIO_EV_INFO_RESET_TIMEOUT) |
				       BIT(IIO_EV_INFO_TAP2_MIN_DELAY),
	},
};

static int usec_to_tapreg_raw(int usec, const int *time_list)
{
	int index;

	for (index = 0; index < BMA400_TAP_TIM_LIST_LEN; index++) {
		if (usec == time_list[index])
			return index;
	}
	return -EINVAL;
}

static ssize_t in_accel_gesture_tap_maxtomin_time_show(struct device *dev,
						       struct device_attribute *attr,
						       char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct bma400_data *data = iio_priv(indio_dev);
	int ret, reg_val, raw, vals[2];

	ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1, &reg_val);
	if (ret)
		return ret;

	raw = FIELD_GET(BMA400_TAP_TICSTH_MSK, reg_val);
	vals[0] = 0;
	vals[1] = tap_max2min_time[raw];

	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
}

static ssize_t in_accel_gesture_tap_maxtomin_time_store(struct device *dev,
							struct device_attribute *attr,
							const char *buf, size_t len)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct bma400_data *data = iio_priv(indio_dev);
	int ret, val_int, val_fract, raw;

	ret = iio_str_to_fixpoint(buf, 100000, &val_int, &val_fract);
	if (ret)
		return ret;

	raw = usec_to_tapreg_raw(val_fract, tap_max2min_time);
	if (raw < 0)
		return -EINVAL;

	ret = regmap_update_bits(data->regmap, BMA400_TAP_CONFIG1,
				 BMA400_TAP_TICSTH_MSK,
				 FIELD_PREP(BMA400_TAP_TICSTH_MSK, raw));
	if (ret)
		return ret;

	return len;
}

static IIO_DEVICE_ATTR_RW(in_accel_gesture_tap_maxtomin_time, 0);

/*
 * Tap interrupts works with 200 Hz input data rate and the time based tap
 * controls are in the terms of data samples so the below calculation is
 * used to convert the configuration values into seconds.
 * e.g.:
 * 60 data samples * 0.005 ms = 0.3 seconds.
 * 80 data samples * 0.005 ms = 0.4 seconds.
 */

/* quiet configuration values in seconds */
static IIO_CONST_ATTR(in_accel_gesture_tap_reset_timeout_available,
		      "0.3 0.4 0.5 0.6");

/* tics_th configuration values in seconds */
static IIO_CONST_ATTR(in_accel_gesture_tap_maxtomin_time_available,
		      "0.03 0.045 0.06 0.09");

/* quiet_dt configuration values in seconds */
static IIO_CONST_ATTR(in_accel_gesture_doubletap_tap2_min_delay_available,
		      "0.02 0.04 0.06 0.08");

/* List of sensitivity values available to configure tap interrupts */
static IIO_CONST_ATTR(in_accel_gesture_tap_value_available, "0 1 2 3 4 5 6 7");

static struct attribute *bma400_event_attributes[] = {
	&iio_const_attr_in_accel_gesture_tap_value_available.dev_attr.attr,
	&iio_const_attr_in_accel_gesture_tap_reset_timeout_available.dev_attr.attr,
	&iio_const_attr_in_accel_gesture_tap_maxtomin_time_available.dev_attr.attr,
	&iio_const_attr_in_accel_gesture_doubletap_tap2_min_delay_available.dev_attr.attr,
	&iio_dev_attr_in_accel_gesture_tap_maxtomin_time.dev_attr.attr,
	NULL
};

static const struct attribute_group bma400_event_attribute_group = {
	.attrs = bma400_event_attributes,
};

#define BMA400_ACC_CHANNEL(_index, _axis) { \
	.type = IIO_ACCEL, \
	.modified = 1, \
	.channel2 = IIO_MOD_##_axis, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
		BIT(IIO_CHAN_INFO_SCALE) | \
		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
		BIT(IIO_CHAN_INFO_SCALE) | \
		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
	.ext_info = bma400_ext_info, \
	.scan_index = _index,	\
	.scan_type = {		\
		.sign = 's',	\
		.realbits = 12,		\
		.storagebits = 16,	\
		.endianness = IIO_LE,	\
	},				\
	.event_spec = bma400_accel_event,			\
	.num_event_specs = ARRAY_SIZE(bma400_accel_event)	\
}

#define BMA400_ACTIVITY_CHANNEL(_chan2) {	\
	.type = IIO_ACTIVITY,			\
	.modified = 1,				\
	.channel2 = _chan2,			\
	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
	.scan_index = -1, /* No buffer support */		\
	.event_spec = &bma400_activity_event,			\
	.num_event_specs = 1,					\
}

static const struct iio_chan_spec bma400_channels[] = {
	BMA400_ACC_CHANNEL(0, X),
	BMA400_ACC_CHANNEL(1, Y),
	BMA400_ACC_CHANNEL(2, Z),
	{
		.type = IIO_TEMP,
		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
		.scan_index = 3,
		.scan_type = {
			.sign = 's',
			.realbits = 8,
			.storagebits = 8,
			.endianness = IIO_LE,
		},
	},
	{
		.type = IIO_STEPS,
		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
				      BIT(IIO_CHAN_INFO_ENABLE),
		.scan_index = -1, /* No buffer support */
		.event_spec = &bma400_step_detect_event,
		.num_event_specs = 1,
	},
	BMA400_ACTIVITY_CHANNEL(IIO_MOD_STILL),
	BMA400_ACTIVITY_CHANNEL(IIO_MOD_WALKING),
	BMA400_ACTIVITY_CHANNEL(IIO_MOD_RUNNING),
	IIO_CHAN_SOFT_TIMESTAMP(4),
};

static int bma400_get_temp_reg(struct bma400_data *data, int *val, int *val2)
{
	unsigned int raw_temp;
	int host_temp;
	int ret;

	if (data->power_mode == POWER_MODE_SLEEP)
		return -EBUSY;

	ret = regmap_read(data->regmap, BMA400_TEMP_DATA_REG, &raw_temp);
	if (ret)
		return ret;

	host_temp = sign_extend32(raw_temp, 7);
	/*
	 * The formula for the TEMP_DATA register in the datasheet
	 * is: x * 0.5 + 23
	 */
	*val = (host_temp >> 1) + 23;
	*val2 = (host_temp & 0x1) * 500000;
	return IIO_VAL_INT_PLUS_MICRO;
}

static int bma400_get_accel_reg(struct bma400_data *data,
				const struct iio_chan_spec *chan,
				int *val)
{
	__le16 raw_accel;
	int lsb_reg;
	int ret;

	if (data->power_mode == POWER_MODE_SLEEP)
		return -EBUSY;

	switch (chan->channel2) {
	case IIO_MOD_X:
		lsb_reg = BMA400_X_AXIS_LSB_REG;
		break;
	case IIO_MOD_Y:
		lsb_reg = BMA400_Y_AXIS_LSB_REG;
		break;
	case IIO_MOD_Z:
		lsb_reg = BMA400_Z_AXIS_LSB_REG;
		break;
	default:
		dev_err(data->dev, "invalid axis channel modifier\n");
		return -EINVAL;
	}

	/* bulk read two registers, with the base being the LSB register */
	ret = regmap_bulk_read(data->regmap, lsb_reg, &raw_accel,
			       sizeof(raw_accel));
	if (ret)
		return ret;

	*val = sign_extend32(le16_to_cpu(raw_accel), 11);
	return IIO_VAL_INT;
}

static void bma400_output_data_rate_from_raw(int raw, unsigned int *val,
					     unsigned int *val2)
{
	*val = BMA400_ACC_ODR_MAX_HZ >> (BMA400_ACC_ODR_MAX_RAW - raw);
	if (raw > BMA400_ACC_ODR_MIN_RAW)
		*val2 = 0;
	else
		*val2 = 500000;
}

static int bma400_get_accel_output_data_rate(struct bma400_data *data)
{
	unsigned int val;
	unsigned int odr;
	int ret;

	switch (data->power_mode) {
	case POWER_MODE_LOW:
		/*
		 * Runs at a fixed rate in low-power mode. See section 4.3
		 * in the datasheet.
		 */
		bma400_output_data_rate_from_raw(BMA400_ACC_ODR_LP_RAW,
						 &data->sample_freq.hz,
						 &data->sample_freq.uhz);
		return 0;
	case POWER_MODE_NORMAL:
		/*
		 * In normal mode the ODR can be found in the ACC_CONFIG1
		 * register.
		 */
		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
		if (ret)
			goto error;

		odr = val & BMA400_ACC_ODR_MASK;
		if (odr < BMA400_ACC_ODR_MIN_RAW ||
		    odr > BMA400_ACC_ODR_MAX_RAW) {
			ret = -EINVAL;
			goto error;
		}

		bma400_output_data_rate_from_raw(odr, &data->sample_freq.hz,
						 &data->sample_freq.uhz);
		return 0;
	case POWER_MODE_SLEEP:
		data->sample_freq.hz = 0;
		data->sample_freq.uhz = 0;
		return 0;
	default:
		ret = 0;
		goto error;
	}
error:
	data->sample_freq.hz = -1;
	data->sample_freq.uhz = -1;
	return ret;
}

static int bma400_set_accel_output_data_rate(struct bma400_data *data,
					     int hz, int uhz)
{
	unsigned int idx;
	unsigned int odr;
	unsigned int val;
	int ret;

	if (hz >= BMA400_ACC_ODR_MIN_WHOLE_HZ) {
		if (uhz || hz > BMA400_ACC_ODR_MAX_HZ)
			return -EINVAL;

		/* Note this works because MIN_WHOLE_HZ is odd */
		idx = __ffs(hz);

		if (hz >> idx != BMA400_ACC_ODR_MIN_WHOLE_HZ)
			return -EINVAL;

		idx += BMA400_ACC_ODR_MIN_RAW + 1;
	} else if (hz == BMA400_ACC_ODR_MIN_HZ && uhz == 500000) {
		idx = BMA400_ACC_ODR_MIN_RAW;
	} else {
		return -EINVAL;
	}

	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
	if (ret)
		return ret;

	/* preserve the range and normal mode osr */
	odr = (~BMA400_ACC_ODR_MASK & val) | idx;

	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG, odr);
	if (ret)
		return ret;

	bma400_output_data_rate_from_raw(idx, &data->sample_freq.hz,
					 &data->sample_freq.uhz);
	return 0;
}

static int bma400_get_accel_oversampling_ratio(struct bma400_data *data)
{
	unsigned int val;
	unsigned int osr;
	int ret;

	/*
	 * The oversampling ratio is stored in a different register
	 * based on the power-mode. In normal mode the OSR is stored
	 * in ACC_CONFIG1. In low-power mode it is stored in
	 * ACC_CONFIG0.
	 */
	switch (data->power_mode) {
	case POWER_MODE_LOW:
		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
		if (ret) {
			data->oversampling_ratio = -1;
			return ret;
		}

		osr = (val & BMA400_LP_OSR_MASK) >> BMA400_LP_OSR_SHIFT;

		data->oversampling_ratio = osr;
		return 0;
	case POWER_MODE_NORMAL:
		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
		if (ret) {
			data->oversampling_ratio = -1;
			return ret;
		}

		osr = (val & BMA400_NP_OSR_MASK) >> BMA400_NP_OSR_SHIFT;

		data->oversampling_ratio = osr;
		return 0;
	case POWER_MODE_SLEEP:
		data->oversampling_ratio = 0;
		return 0;
	default:
		data->oversampling_ratio = -1;
		return -EINVAL;
	}
}

static int bma400_set_accel_oversampling_ratio(struct bma400_data *data,
					       int val)
{
	unsigned int acc_config;
	int ret;

	if (val & ~BMA400_TWO_BITS_MASK)
		return -EINVAL;

	/*
	 * The oversampling ratio is stored in a different register
	 * based on the power-mode.
	 */
	switch (data->power_mode) {
	case POWER_MODE_LOW:
		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG,
				  &acc_config);
		if (ret)
			return ret;

		ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
				   (acc_config & ~BMA400_LP_OSR_MASK) |
				   (val << BMA400_LP_OSR_SHIFT));
		if (ret) {
			dev_err(data->dev, "Failed to write out OSR\n");
			return ret;
		}

		data->oversampling_ratio = val;
		return 0;
	case POWER_MODE_NORMAL:
		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG,
				  &acc_config);
		if (ret)
			return ret;

		ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
				   (acc_config & ~BMA400_NP_OSR_MASK) |
				   (val << BMA400_NP_OSR_SHIFT));
		if (ret) {
			dev_err(data->dev, "Failed to write out OSR\n");
			return ret;
		}

		data->oversampling_ratio = val;
		return 0;
	default:
		return -EINVAL;
	}
	return ret;
}

static int bma400_accel_scale_to_raw(struct bma400_data *data,
				     unsigned int val)
{
	int raw;

	if (val == 0)
		return -EINVAL;

	/* Note this works because BMA400_SCALE_MIN is odd */
	raw = __ffs(val);

	if (val >> raw != BMA400_SCALE_MIN)
		return -EINVAL;

	return raw;
}

static int bma400_get_accel_scale(struct bma400_data *data)
{
	unsigned int raw_scale;
	unsigned int val;
	int ret;

	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
	if (ret)
		return ret;

	raw_scale = (val & BMA400_ACC_SCALE_MASK) >> BMA400_SCALE_SHIFT;
	if (raw_scale > BMA400_TWO_BITS_MASK)
		return -EINVAL;

	data->scale = BMA400_SCALE_MIN << raw_scale;

	return 0;
}

static int bma400_set_accel_scale(struct bma400_data *data, unsigned int val)
{
	unsigned int acc_config;
	int raw;
	int ret;

	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &acc_config);
	if (ret)
		return ret;

	raw = bma400_accel_scale_to_raw(data, val);
	if (raw < 0)
		return raw;

	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
			   (acc_config & ~BMA400_ACC_SCALE_MASK) |
			   (raw << BMA400_SCALE_SHIFT));
	if (ret)
		return ret;

	data->scale = val;
	return 0;
}

static int bma400_get_power_mode(struct bma400_data *data)
{
	unsigned int val;
	int ret;

	ret = regmap_read(data->regmap, BMA400_STATUS_REG, &val);
	if (ret) {
		dev_err(data->dev, "Failed to read status register\n");
		return ret;
	}

	data->power_mode = (val >> 1) & BMA400_TWO_BITS_MASK;
	return 0;
}

static int bma400_set_power_mode(struct bma400_data *data,
				 enum bma400_power_mode mode)
{
	unsigned int val;
	int ret;

	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
	if (ret)
		return ret;

	if (data->power_mode == mode)
		return 0;

	if (mode == POWER_MODE_INVALID)
		return -EINVAL;

	/* Preserve the low-power oversample ratio etc */
	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
			   mode | (val & ~BMA400_TWO_BITS_MASK));
	if (ret) {
		dev_err(data->dev, "Failed to write to power-mode\n");
		return ret;
	}

	data->power_mode = mode;

	/*
	 * Update our cached osr and odr based on the new
	 * power-mode.
	 */
	bma400_get_accel_output_data_rate(data);
	bma400_get_accel_oversampling_ratio(data);
	return 0;
}

static int bma400_enable_steps(struct bma400_data *data, int val)
{
	int ret;

	if (data->steps_enabled == val)
		return 0;

	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG1_REG,
				 BMA400_STEP_INT_MSK,
				 FIELD_PREP(BMA400_STEP_INT_MSK, val ? 1 : 0));
	if (ret)
		return ret;
	data->steps_enabled = val;
	return ret;
}

static int bma400_get_steps_reg(struct bma400_data *data, int *val)
{
	int ret;

	u8 *steps_raw __free(kfree) = kmalloc(BMA400_STEP_RAW_LEN, GFP_KERNEL);
	if (!steps_raw)
		return -ENOMEM;

	ret = regmap_bulk_read(data->regmap, BMA400_STEP_CNT0_REG,
			       steps_raw, BMA400_STEP_RAW_LEN);
	if (ret)
		return ret;

	*val = get_unaligned_le24(steps_raw);

	return IIO_VAL_INT;
}

static void bma400_init_tables(void)
{
	int raw;
	int i;

	for (i = 0; i + 1 < ARRAY_SIZE(bma400_sample_freqs); i += 2) {
		raw = (i / 2) + 5;
		bma400_output_data_rate_from_raw(raw, &bma400_sample_freqs[i],
						 &bma400_sample_freqs[i + 1]);
	}

	for (i = 0; i + 1 < ARRAY_SIZE(bma400_scales); i += 2) {
		raw = i / 2;
		bma400_scales[i] = 0;
		bma400_scales[i + 1] = BMA400_SCALE_MIN << raw;
	}
}

static void bma400_power_disable(void *data_ptr)
{
	struct bma400_data *data = data_ptr;
	int ret;

	mutex_lock(&data->mutex);
	ret = bma400_set_power_mode(data, POWER_MODE_SLEEP);
	mutex_unlock(&data->mutex);
	if (ret)
		dev_warn(data->dev, "Failed to put device into sleep mode (%pe)\n",
			 ERR_PTR(ret));
}

static enum iio_modifier bma400_act_to_mod(enum bma400_activity activity)
{
	switch (activity) {
	case BMA400_STILL:
		return IIO_MOD_STILL;
	case BMA400_WALKING:
		return IIO_MOD_WALKING;
	case BMA400_RUNNING:
		return IIO_MOD_RUNNING;
	default:
		return IIO_NO_MOD;
	}
}

static int bma400_init(struct bma400_data *data)
{
	static const char * const regulator_names[] = { "vdd", "vddio" };
	unsigned int val;
	int ret;

	ret = devm_regulator_bulk_get_enable(data->dev,
					     ARRAY_SIZE(regulator_names),
					     regulator_names);
	if (ret)
		return dev_err_probe(data->dev, ret, "Failed to get regulators\n");

	/* Try to read chip_id register. It must return 0x90. */
	ret = regmap_read(data->regmap, BMA400_CHIP_ID_REG, &val);
	if (ret) {
		dev_err(data->dev, "Failed to read chip id register\n");
		return ret;
	}

	if (val != BMA400_ID_REG_VAL) {
		dev_err(data->dev, "Chip ID mismatch\n");
		return -ENODEV;
	}

	ret = bma400_get_power_mode(data);
	if (ret) {
		dev_err(data->dev, "Failed to get the initial power-mode\n");
		return ret;
	}

	if (data->power_mode != POWER_MODE_NORMAL) {
		ret = bma400_set_power_mode(data, POWER_MODE_NORMAL);
		if (ret) {
			dev_err(data->dev, "Failed to wake up the device\n");
			return ret;
		}
		/*
		 * TODO: The datasheet waits 1500us here in the example, but
		 * lists 2/ODR as the wakeup time.
		 */
		usleep_range(1500, 2000);
	}

	ret = devm_add_action_or_reset(data->dev, bma400_power_disable, data);
	if (ret)
		return ret;

	bma400_init_tables();

	ret = bma400_get_accel_output_data_rate(data);
	if (ret)
		return ret;

	ret = bma400_get_accel_oversampling_ratio(data);
	if (ret)
		return ret;

	ret = bma400_get_accel_scale(data);
	if (ret)
		return ret;

	/* Configure INT1 pin to open drain */
	ret = regmap_write(data->regmap, BMA400_INT_IO_CTRL_REG, 0x06);
	if (ret)
		return ret;
	/*
	 * Once the interrupt engine is supported we might use the
	 * data_src_reg, but for now ensure this is set to the
	 * variable ODR filter selectable by the sample frequency
	 * channel.
	 */
	return regmap_write(data->regmap, BMA400_ACC_CONFIG2_REG, 0x00);
}

static int bma400_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan, int *val,
			   int *val2, long mask)
{
	struct bma400_data *data = iio_priv(indio_dev);
	unsigned int activity;
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_PROCESSED:
		switch (chan->type) {
		case IIO_TEMP:
			mutex_lock(&data->mutex);
			ret = bma400_get_temp_reg(data, val, val2);
			mutex_unlock(&data->mutex);
			return ret;
		case IIO_STEPS:
			return bma400_get_steps_reg(data, val);
		case IIO_ACTIVITY:
			ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
					  &activity);
			if (ret)
				return ret;
			/*
			 * The device does not support confidence value levels,
			 * so we will always have 100% for current activity and
			 * 0% for the others.
			 */
			if (chan->channel2 == bma400_act_to_mod(activity))
				*val = 100;
			else
				*val = 0;
			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_RAW:
		mutex_lock(&data->mutex);
		ret = bma400_get_accel_reg(data, chan, val);
		mutex_unlock(&data->mutex);
		return ret;
	case IIO_CHAN_INFO_SAMP_FREQ:
		switch (chan->type) {
		case IIO_ACCEL:
			if (data->sample_freq.hz < 0)
				return -EINVAL;

			*val = data->sample_freq.hz;
			*val2 = data->sample_freq.uhz;
			return IIO_VAL_INT_PLUS_MICRO;
		case IIO_TEMP:
			/*
			 * Runs at a fixed sampling frequency. See Section 4.4
			 * of the datasheet.
			 */
			*val = 6;
			*val2 = 250000;
			return IIO_VAL_INT_PLUS_MICRO;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_SCALE:
		*val = 0;
		*val2 = data->scale;
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
		/*
		 * TODO: We could avoid this logic and returning -EINVAL here if
		 * we set both the low-power and normal mode OSR registers when
		 * we configure the device.
		 */
		if (data->oversampling_ratio < 0)
			return -EINVAL;

		*val = data->oversampling_ratio;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_ENABLE:
		*val = data->steps_enabled;
		return IIO_VAL_INT;
	default:
		return -EINVAL;
	}
}

static int bma400_read_avail(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     const int **vals, int *type, int *length,
			     long mask)
{
	switch (mask) {
	case IIO_CHAN_INFO_SCALE:
		*type = IIO_VAL_INT_PLUS_MICRO;
		*vals = bma400_scales;
		*length = ARRAY_SIZE(bma400_scales);
		return IIO_AVAIL_LIST;
	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
		*type = IIO_VAL_INT;
		*vals = bma400_osr_range;
		*length = ARRAY_SIZE(bma400_osr_range);
		return IIO_AVAIL_RANGE;
	case IIO_CHAN_INFO_SAMP_FREQ:
		*type = IIO_VAL_INT_PLUS_MICRO;
		*vals = bma400_sample_freqs;
		*length = ARRAY_SIZE(bma400_sample_freqs);
		return IIO_AVAIL_LIST;
	default:
		return -EINVAL;
	}
}

static int bma400_write_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan, int val, int val2,
			    long mask)
{
	struct bma400_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
		/*
		 * The sample frequency is readonly for the temperature
		 * register and a fixed value in low-power mode.
		 */
		if (chan->type != IIO_ACCEL)
			return -EINVAL;

		mutex_lock(&data->mutex);
		ret = bma400_set_accel_output_data_rate(data, val, val2);
		mutex_unlock(&data->mutex);
		return ret;
	case IIO_CHAN_INFO_SCALE:
		if (val != 0 ||
		    val2 < BMA400_SCALE_MIN || val2 > BMA400_SCALE_MAX)
			return -EINVAL;

		mutex_lock(&data->mutex);
		ret = bma400_set_accel_scale(data, val2);
		mutex_unlock(&data->mutex);
		return ret;
	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
		mutex_lock(&data->mutex);
		ret = bma400_set_accel_oversampling_ratio(data, val);
		mutex_unlock(&data->mutex);
		return ret;
	case IIO_CHAN_INFO_ENABLE:
		mutex_lock(&data->mutex);
		ret = bma400_enable_steps(data, val);
		mutex_unlock(&data->mutex);
		return ret;
	default:
		return -EINVAL;
	}
}

static int bma400_write_raw_get_fmt(struct iio_dev *indio_dev,
				    struct iio_chan_spec const *chan,
				    long mask)
{
	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SCALE:
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_ENABLE:
		return IIO_VAL_INT;
	default:
		return -EINVAL;
	}
}

static int bma400_read_event_config(struct iio_dev *indio_dev,
				    const struct iio_chan_spec *chan,
				    enum iio_event_type type,
				    enum iio_event_direction dir)
{
	struct bma400_data *data = iio_priv(indio_dev);

	switch (chan->type) {
	case IIO_ACCEL:
		switch (dir) {
		case IIO_EV_DIR_RISING:
			return FIELD_GET(BMA400_INT_GEN1_MSK,
					 data->generic_event_en);
		case IIO_EV_DIR_FALLING:
			return FIELD_GET(BMA400_INT_GEN2_MSK,
					 data->generic_event_en);
		case IIO_EV_DIR_SINGLETAP:
			return FIELD_GET(BMA400_S_TAP_MSK,
					 data->tap_event_en_bitmask);
		case IIO_EV_DIR_DOUBLETAP:
			return FIELD_GET(BMA400_D_TAP_MSK,
					 data->tap_event_en_bitmask);
		default:
			return -EINVAL;
		}
	case IIO_STEPS:
		return data->step_event_en;
	case IIO_ACTIVITY:
		return data->activity_event_en;
	default:
		return -EINVAL;
	}
}

static int bma400_steps_event_enable(struct bma400_data *data, int state)
{
	int ret;

	ret = bma400_enable_steps(data, 1);
	if (ret)
		return ret;

	ret = regmap_update_bits(data->regmap, BMA400_INT12_MAP_REG,
				 BMA400_STEP_INT_MSK,
				 FIELD_PREP(BMA400_STEP_INT_MSK,
					    state));
	if (ret)
		return ret;
	data->step_event_en = state;
	return 0;
}

static int bma400_activity_event_en(struct bma400_data *data,
				    enum iio_event_direction dir,
				    int state)
{
	int ret, reg, msk, value;
	int field_value = 0;

	switch (dir) {
	case IIO_EV_DIR_RISING:
		reg = BMA400_GEN1INT_CONFIG0;
		msk = BMA400_INT_GEN1_MSK;
		value = 2;
		set_mask_bits(&field_value, BMA400_INT_GEN1_MSK,
			      FIELD_PREP(BMA400_INT_GEN1_MSK, state));
		break;
	case IIO_EV_DIR_FALLING:
		reg = BMA400_GEN2INT_CONFIG0;
		msk = BMA400_INT_GEN2_MSK;
		value = 0;
		set_mask_bits(&field_value, BMA400_INT_GEN2_MSK,
			      FIELD_PREP(BMA400_INT_GEN2_MSK, state));
		break;
	default:
		return -EINVAL;
	}

	/* Enabling all axis for interrupt evaluation */
	ret = regmap_write(data->regmap, reg, 0xF8);
	if (ret)
		return ret;

	/* OR combination of all axis for interrupt evaluation */
	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG1_OFF, value);
	if (ret)
		return ret;

	/* Initial value to avoid interrupts while enabling*/
	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG2_OFF, 0x0A);
	if (ret)
		return ret;

	/* Initial duration value to avoid interrupts while enabling*/
	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG31_OFF, 0x0F);
	if (ret)
		return ret;

	ret = regmap_update_bits(data->regmap, BMA400_INT1_MAP_REG, msk,
				 field_value);
	if (ret)
		return ret;

	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG0_REG, msk,
				 field_value);
	if (ret)
		return ret;

	set_mask_bits(&data->generic_event_en, msk, field_value);
	return 0;
}

static int bma400_tap_event_en(struct bma400_data *data,
			       enum iio_event_direction dir, int state)
{
	unsigned int mask, field_value;
	int ret;

	/*
	 * Tap interrupts can be configured only in normal mode.
	 * See table in section 4.3 "Power modes - performance modes" of
	 * datasheet v1.2.
	 */
	if (data->power_mode != POWER_MODE_NORMAL)
		return -EINVAL;

	/*
	 * Tap interrupts are operating with a data rate of 200Hz.
	 * See section 4.7 "Tap sensing interrupt" in datasheet v1.2.
	 */
	if (data->sample_freq.hz != 200 && state) {
		dev_err(data->dev, "Invalid data rate for tap interrupts.\n");
		return -EINVAL;
	}

	ret = regmap_update_bits(data->regmap, BMA400_INT12_MAP_REG,
				 BMA400_S_TAP_MSK,
				 FIELD_PREP(BMA400_S_TAP_MSK, state));
	if (ret)
		return ret;

	switch (dir) {
	case IIO_EV_DIR_SINGLETAP:
		mask = BMA400_S_TAP_MSK;
		set_mask_bits(&field_value, BMA400_S_TAP_MSK,
			      FIELD_PREP(BMA400_S_TAP_MSK, state));
		break;
	case IIO_EV_DIR_DOUBLETAP:
		mask = BMA400_D_TAP_MSK;
		set_mask_bits(&field_value, BMA400_D_TAP_MSK,
			      FIELD_PREP(BMA400_D_TAP_MSK, state));
		break;
	default:
		return -EINVAL;
	}

	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG1_REG, mask,
				 field_value);
	if (ret)
		return ret;

	set_mask_bits(&data->tap_event_en_bitmask, mask, field_value);

	return 0;
}

static int bma400_disable_adv_interrupt(struct bma400_data *data)
{
	int ret;

	ret = regmap_write(data->regmap, BMA400_INT_CONFIG0_REG, 0);
	if (ret)
		return ret;

	ret = regmap_write(data->regmap, BMA400_INT_CONFIG1_REG, 0);
	if (ret)
		return ret;

	data->tap_event_en_bitmask = 0;
	data->generic_event_en = 0;
	data->step_event_en = false;
	data->activity_event_en = false;

	return 0;
}

static int bma400_write_event_config(struct iio_dev *indio_dev,
				     const struct iio_chan_spec *chan,
				     enum iio_event_type type,
				     enum iio_event_direction dir, int state)
{
	struct bma400_data *data = iio_priv(indio_dev);
	int ret;

	switch (chan->type) {
	case IIO_ACCEL:
		switch (type) {
		case IIO_EV_TYPE_MAG:
			mutex_lock(&data->mutex);
			ret = bma400_activity_event_en(data, dir, state);
			mutex_unlock(&data->mutex);
			return ret;
		case IIO_EV_TYPE_GESTURE:
			mutex_lock(&data->mutex);
			ret = bma400_tap_event_en(data, dir, state);
			mutex_unlock(&data->mutex);
			return ret;
		default:
			return -EINVAL;
		}
	case IIO_STEPS:
		mutex_lock(&data->mutex);
		ret = bma400_steps_event_enable(data, state);
		mutex_unlock(&data->mutex);
		return ret;
	case IIO_ACTIVITY:
		mutex_lock(&data->mutex);
		if (!data->step_event_en) {
			ret = bma400_steps_event_enable(data, true);
			if (ret) {
				mutex_unlock(&data->mutex);
				return ret;
			}
		}
		data->activity_event_en = state;
		mutex_unlock(&data->mutex);
		return 0;
	default:
		return -EINVAL;
	}
}

static int get_gen_config_reg(enum iio_event_direction dir)
{
	switch (dir) {
	case IIO_EV_DIR_FALLING:
		return BMA400_GEN2INT_CONFIG0;
	case IIO_EV_DIR_RISING:
		return BMA400_GEN1INT_CONFIG0;
	default:
		return -EINVAL;
	}
}

static int bma400_read_event_value(struct iio_dev *indio_dev,
				   const struct iio_chan_spec *chan,
				   enum iio_event_type type,
				   enum iio_event_direction dir,
				   enum iio_event_info info,
				   int *val, int *val2)
{
	struct bma400_data *data = iio_priv(indio_dev);
	int ret, reg, reg_val, raw;

	if (chan->type != IIO_ACCEL)
		return -EINVAL;

	switch (type) {
	case IIO_EV_TYPE_MAG:
		reg = get_gen_config_reg(dir);
		if (reg < 0)
			return -EINVAL;

		*val2 = 0;
		switch (info) {
		case IIO_EV_INFO_VALUE:
			ret = regmap_read(data->regmap,
					  reg + BMA400_GEN_CONFIG2_OFF,
					  val);
			if (ret)
				return ret;
			return IIO_VAL_INT;
		case IIO_EV_INFO_PERIOD:
			mutex_lock(&data->mutex);
			ret = regmap_bulk_read(data->regmap,
					       reg + BMA400_GEN_CONFIG3_OFF,
					       &data->duration,
					       sizeof(data->duration));
			if (ret) {
				mutex_unlock(&data->mutex);
				return ret;
			}
			*val = be16_to_cpu(data->duration);
			mutex_unlock(&data->mutex);
			return IIO_VAL_INT;
		case IIO_EV_INFO_HYSTERESIS:
			ret = regmap_read(data->regmap, reg, val);
			if (ret)
				return ret;
			*val = FIELD_GET(BMA400_GEN_HYST_MSK, *val);
			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_EV_TYPE_GESTURE:
		switch (info) {
		case IIO_EV_INFO_VALUE:
			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG,
					  &reg_val);
			if (ret)
				return ret;

			*val = FIELD_GET(BMA400_TAP_SEN_MSK, reg_val);
			return IIO_VAL_INT;
		case IIO_EV_INFO_RESET_TIMEOUT:
			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1,
					  &reg_val);
			if (ret)
				return ret;

			raw = FIELD_GET(BMA400_TAP_QUIET_MSK, reg_val);
			*val = 0;
			*val2 = tap_reset_timeout[raw];
			return IIO_VAL_INT_PLUS_MICRO;
		case IIO_EV_INFO_TAP2_MIN_DELAY:
			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1,
					  &reg_val);
			if (ret)
				return ret;

			raw = FIELD_GET(BMA400_TAP_QUIETDT_MSK, reg_val);
			*val = 0;
			*val2 = double_tap2_min_delay[raw];
			return IIO_VAL_INT_PLUS_MICRO;
		default:
			return -EINVAL;
		}
	default:
		return -EINVAL;
	}
}

static int bma400_write_event_value(struct iio_dev *indio_dev,
				    const struct iio_chan_spec *chan,
				    enum iio_event_type type,
				    enum iio_event_direction dir,
				    enum iio_event_info info,
				    int val, int val2)
{
	struct bma400_data *data = iio_priv(indio_dev);
	int reg, ret, raw;

	if (chan->type != IIO_ACCEL)
		return -EINVAL;

	switch (type) {
	case IIO_EV_TYPE_MAG:
		reg = get_gen_config_reg(dir);
		if (reg < 0)
			return -EINVAL;

		switch (info) {
		case IIO_EV_INFO_VALUE:
			if (val < 1 || val > 255)
				return -EINVAL;

			return regmap_write(data->regmap,
					    reg + BMA400_GEN_CONFIG2_OFF,
					    val);
		case IIO_EV_INFO_PERIOD:
			if (val < 1 || val > 65535)
				return -EINVAL;

			mutex_lock(&data->mutex);
			put_unaligned_be16(val, &data->duration);
			ret = regmap_bulk_write(data->regmap,
						reg + BMA400_GEN_CONFIG3_OFF,
						&data->duration,
						sizeof(data->duration));
			mutex_unlock(&data->mutex);
			return ret;
		case IIO_EV_INFO_HYSTERESIS:
			if (val < 0 || val > 3)
				return -EINVAL;

			return regmap_update_bits(data->regmap, reg,
						  BMA400_GEN_HYST_MSK,
						  FIELD_PREP(BMA400_GEN_HYST_MSK,
							     val));
		default:
			return -EINVAL;
		}
	case IIO_EV_TYPE_GESTURE:
		switch (info) {
		case IIO_EV_INFO_VALUE:
			if (val < 0 || val > 7)
				return -EINVAL;

			return regmap_update_bits(data->regmap,
						  BMA400_TAP_CONFIG,
						  BMA400_TAP_SEN_MSK,
						  FIELD_PREP(BMA400_TAP_SEN_MSK,
							     val));
		case IIO_EV_INFO_RESET_TIMEOUT:
			raw = usec_to_tapreg_raw(val2, tap_reset_timeout);
			if (raw < 0)
				return -EINVAL;

			return regmap_update_bits(data->regmap,
						  BMA400_TAP_CONFIG1,
						  BMA400_TAP_QUIET_MSK,
						  FIELD_PREP(BMA400_TAP_QUIET_MSK,
							     raw));
		case IIO_EV_INFO_TAP2_MIN_DELAY:
			raw = usec_to_tapreg_raw(val2, double_tap2_min_delay);
			if (raw < 0)
				return -EINVAL;

			return regmap_update_bits(data->regmap,
						  BMA400_TAP_CONFIG1,
						  BMA400_TAP_QUIETDT_MSK,
						  FIELD_PREP(BMA400_TAP_QUIETDT_MSK,
							     raw));
		default:
			return -EINVAL;
		}
	default:
		return -EINVAL;
	}
}

static int bma400_data_rdy_trigger_set_state(struct iio_trigger *trig,
					     bool state)
{
	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	struct bma400_data *data = iio_priv(indio_dev);
	int ret;

	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG0_REG,
				 BMA400_INT_DRDY_MSK,
				 FIELD_PREP(BMA400_INT_DRDY_MSK, state));
	if (ret)
		return ret;

	return regmap_update_bits(data->regmap, BMA400_INT1_MAP_REG,
				  BMA400_INT_DRDY_MSK,
				  FIELD_PREP(BMA400_INT_DRDY_MSK, state));
}

static const unsigned long bma400_avail_scan_masks[] = {
	BIT(BMA400_ACCL_X) | BIT(BMA400_ACCL_Y) | BIT(BMA400_ACCL_Z),
	BIT(BMA400_ACCL_X) | BIT(BMA400_ACCL_Y) | BIT(BMA400_ACCL_Z)
	| BIT(BMA400_TEMP),
	0
};

static const struct iio_info bma400_info = {
	.read_raw          = bma400_read_raw,
	.read_avail        = bma400_read_avail,
	.write_raw         = bma400_write_raw,
	.write_raw_get_fmt = bma400_write_raw_get_fmt,
	.read_event_config = bma400_read_event_config,
	.write_event_config = bma400_write_event_config,
	.write_event_value = bma400_write_event_value,
	.read_event_value = bma400_read_event_value,
	.event_attrs = &bma400_event_attribute_group,
};

static const struct iio_trigger_ops bma400_trigger_ops = {
	.set_trigger_state = &bma400_data_rdy_trigger_set_state,
	.validate_device = &iio_trigger_validate_own_device,
};

static irqreturn_t bma400_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct bma400_data *data = iio_priv(indio_dev);
	int ret, temp;

	/* Lock to protect the data->buffer */
	mutex_lock(&data->mutex);

	/* bulk read six registers, with the base being the LSB register */
	ret = regmap_bulk_read(data->regmap, BMA400_X_AXIS_LSB_REG,
			       &data->buffer.buff, sizeof(data->buffer.buff));
	if (ret)
		goto unlock_err;

	if (test_bit(BMA400_TEMP, indio_dev->active_scan_mask)) {
		ret = regmap_read(data->regmap, BMA400_TEMP_DATA_REG, &temp);
		if (ret)
			goto unlock_err;

		data->buffer.temperature = temp;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
					   iio_get_time_ns(indio_dev));

	mutex_unlock(&data->mutex);
	iio_trigger_notify_done(indio_dev->trig);
	return IRQ_HANDLED;

unlock_err:
	mutex_unlock(&data->mutex);
	return IRQ_NONE;
}

static irqreturn_t bma400_interrupt(int irq, void *private)
{
	struct iio_dev *indio_dev = private;
	struct bma400_data *data = iio_priv(indio_dev);
	s64 timestamp = iio_get_time_ns(indio_dev);
	unsigned int act, ev_dir = IIO_EV_DIR_NONE;
	int ret;

	/* Lock to protect the data->status */
	mutex_lock(&data->mutex);
	ret = regmap_bulk_read(data->regmap, BMA400_INT_STAT0_REG,
			       &data->status,
			       sizeof(data->status));
	/*
	 * if none of the bit is set in the status register then it is
	 * spurious interrupt.
	 */
	if (ret || !data->status)
		goto unlock_err;

	/*
	 * Disable all advance interrupts if interrupt engine overrun occurs.
	 * See section 4.7 "Interrupt engine overrun" in datasheet v1.2.
	 */
	if (FIELD_GET(BMA400_INT_ENG_OVRUN_MSK, le16_to_cpu(data->status))) {
		bma400_disable_adv_interrupt(data);
		dev_err(data->dev, "Interrupt engine overrun\n");
		goto unlock_err;
	}

	if (FIELD_GET(BMA400_INT_S_TAP_MSK, le16_to_cpu(data->status)))
		iio_push_event(indio_dev,
			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
						  IIO_MOD_X_OR_Y_OR_Z,
						  IIO_EV_TYPE_GESTURE,
						  IIO_EV_DIR_SINGLETAP),
			       timestamp);

	if (FIELD_GET(BMA400_INT_D_TAP_MSK, le16_to_cpu(data->status)))
		iio_push_event(indio_dev,
			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
						  IIO_MOD_X_OR_Y_OR_Z,
						  IIO_EV_TYPE_GESTURE,
						  IIO_EV_DIR_DOUBLETAP),
			       timestamp);

	if (FIELD_GET(BMA400_INT_GEN1_MSK, le16_to_cpu(data->status)))
		ev_dir = IIO_EV_DIR_RISING;

	if (FIELD_GET(BMA400_INT_GEN2_MSK, le16_to_cpu(data->status)))
		ev_dir = IIO_EV_DIR_FALLING;

	if (ev_dir != IIO_EV_DIR_NONE) {
		iio_push_event(indio_dev,
			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
						  IIO_MOD_X_OR_Y_OR_Z,
						  IIO_EV_TYPE_MAG, ev_dir),
			       timestamp);
	}

	if (FIELD_GET(BMA400_STEP_STAT_MASK, le16_to_cpu(data->status))) {
		iio_push_event(indio_dev,
			       IIO_MOD_EVENT_CODE(IIO_STEPS, 0, IIO_NO_MOD,
						  IIO_EV_TYPE_CHANGE,
						  IIO_EV_DIR_NONE),
			       timestamp);

		if (data->activity_event_en) {
			ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
					  &act);
			if (ret)
				goto unlock_err;

			iio_push_event(indio_dev,
				       IIO_MOD_EVENT_CODE(IIO_ACTIVITY, 0,
							  bma400_act_to_mod(act),
							  IIO_EV_TYPE_CHANGE,
							  IIO_EV_DIR_NONE),
				       timestamp);
		}
	}

	if (FIELD_GET(BMA400_INT_DRDY_MSK, le16_to_cpu(data->status))) {
		mutex_unlock(&data->mutex);
		iio_trigger_poll_nested(data->trig);
		return IRQ_HANDLED;
	}

	mutex_unlock(&data->mutex);
	return IRQ_HANDLED;

unlock_err:
	mutex_unlock(&data->mutex);
	return IRQ_NONE;
}

int bma400_probe(struct device *dev, struct regmap *regmap, int irq,
		 const char *name)
{
	struct iio_dev *indio_dev;
	struct bma400_data *data;
	int ret;

	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
	if (!indio_dev)
		return -ENOMEM;

	data = iio_priv(indio_dev);
	data->regmap = regmap;
	data->dev = dev;

	ret = bma400_init(data);
	if (ret)
		return ret;

	ret = iio_read_mount_matrix(dev, &data->orientation);
	if (ret)
		return ret;

	mutex_init(&data->mutex);
	indio_dev->name = name;
	indio_dev->info = &bma400_info;
	indio_dev->channels = bma400_channels;
	indio_dev->num_channels = ARRAY_SIZE(bma400_channels);
	indio_dev->available_scan_masks = bma400_avail_scan_masks;
	indio_dev->modes = INDIO_DIRECT_MODE;

	if (irq > 0) {
		data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
						    indio_dev->name,
						    iio_device_id(indio_dev));
		if (!data->trig)
			return -ENOMEM;

		data->trig->ops = &bma400_trigger_ops;
		iio_trigger_set_drvdata(data->trig, indio_dev);

		ret = devm_iio_trigger_register(data->dev, data->trig);
		if (ret)
			return dev_err_probe(data->dev, ret,
					     "iio trigger register fail\n");

		indio_dev->trig = iio_trigger_get(data->trig);
		ret = devm_request_threaded_irq(dev, irq, NULL,
						&bma400_interrupt,
						IRQF_TRIGGER_RISING | IRQF_ONESHOT,
						indio_dev->name, indio_dev);
		if (ret)
			return dev_err_probe(data->dev, ret,
					     "request irq %d failed\n", irq);
	}

	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
					      &bma400_trigger_handler, NULL);
	if (ret)
		return dev_err_probe(data->dev, ret,
				     "iio triggered buffer setup failed\n");

	return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS(bma400_probe, IIO_BMA400);

MODULE_AUTHOR("Dan Robertson <dan@dlrobertson.com>");
MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>");
MODULE_DESCRIPTION("Bosch BMA400 triaxial acceleration sensor core");
MODULE_LICENSE("GPL");