Linux Audio

Check our new training course

Loading...
   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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2021 Joe Sandom <joe.g.sandom@gmail.com>
 *
 * Datasheet: https://ams.com/tsl25911#tab/documents
 *
 * Device driver for the TAOS TSL2591. This is a very-high sensitivity
 * light-to-digital converter that transforms light intensity into a digital
 * signal.
 */

#include <linux/bitfield.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pm_runtime.h>
#include <linux/sysfs.h>

#include <asm/unaligned.h>

#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

/* ADC integration time, field value to time in ms */
#define TSL2591_FVAL_TO_MSEC(x) (((x) + 1) * 100)
/* ADC integration time, field value to time in seconds */
#define TSL2591_FVAL_TO_SEC(x) ((x) + 1)
/* ADC integration time, time in seconds to field value */
#define TSL2591_SEC_TO_FVAL(x) ((x) - 1)

/* TSL2591 register set */
#define TSL2591_ENABLE      0x00
#define TSL2591_CONTROL     0x01
#define TSL2591_AILTL       0x04
#define TSL2591_AILTH       0x05
#define TSL2591_AIHTL       0x06
#define TSL2591_AIHTH       0x07
#define TSL2591_NP_AILTL    0x08
#define TSL2591_NP_AILTH    0x09
#define TSL2591_NP_AIHTL    0x0A
#define TSL2591_NP_AIHTH    0x0B
#define TSL2591_PERSIST     0x0C
#define TSL2591_PACKAGE_ID  0x11
#define TSL2591_DEVICE_ID   0x12
#define TSL2591_STATUS      0x13
#define TSL2591_C0_DATAL    0x14
#define TSL2591_C0_DATAH    0x15
#define TSL2591_C1_DATAL    0x16
#define TSL2591_C1_DATAH    0x17

/* TSL2591 command register definitions */
#define TSL2591_CMD_NOP             0xA0
#define TSL2591_CMD_SF_INTSET       0xE4
#define TSL2591_CMD_SF_CALS_I       0xE5
#define TSL2591_CMD_SF_CALS_NPI     0xE7
#define TSL2591_CMD_SF_CNP_ALSI     0xEA

/* TSL2591 enable register definitions */
#define TSL2591_PWR_ON              0x01
#define TSL2591_PWR_OFF             0x00
#define TSL2591_ENABLE_ALS          0x02
#define TSL2591_ENABLE_ALS_INT      0x10
#define TSL2591_ENABLE_SLEEP_INT    0x40
#define TSL2591_ENABLE_NP_INT       0x80

/* TSL2591 control register definitions */
#define TSL2591_CTRL_ALS_INTEGRATION_100MS  0x00
#define TSL2591_CTRL_ALS_INTEGRATION_200MS  0x01
#define TSL2591_CTRL_ALS_INTEGRATION_300MS  0x02
#define TSL2591_CTRL_ALS_INTEGRATION_400MS  0x03
#define TSL2591_CTRL_ALS_INTEGRATION_500MS  0x04
#define TSL2591_CTRL_ALS_INTEGRATION_600MS  0x05
#define TSL2591_CTRL_ALS_LOW_GAIN           0x00
#define TSL2591_CTRL_ALS_MED_GAIN           0x10
#define TSL2591_CTRL_ALS_HIGH_GAIN          0x20
#define TSL2591_CTRL_ALS_MAX_GAIN           0x30
#define TSL2591_CTRL_SYS_RESET              0x80

/* TSL2591 persist register definitions */
#define TSL2591_PRST_ALS_INT_CYCLE_0        0x00
#define TSL2591_PRST_ALS_INT_CYCLE_ANY      0x01
#define TSL2591_PRST_ALS_INT_CYCLE_2        0x02
#define TSL2591_PRST_ALS_INT_CYCLE_3        0x03
#define TSL2591_PRST_ALS_INT_CYCLE_5        0x04
#define TSL2591_PRST_ALS_INT_CYCLE_10       0x05
#define TSL2591_PRST_ALS_INT_CYCLE_15       0x06
#define TSL2591_PRST_ALS_INT_CYCLE_20       0x07
#define TSL2591_PRST_ALS_INT_CYCLE_25       0x08
#define TSL2591_PRST_ALS_INT_CYCLE_30       0x09
#define TSL2591_PRST_ALS_INT_CYCLE_35       0x0A
#define TSL2591_PRST_ALS_INT_CYCLE_40       0x0B
#define TSL2591_PRST_ALS_INT_CYCLE_45       0x0C
#define TSL2591_PRST_ALS_INT_CYCLE_50       0x0D
#define TSL2591_PRST_ALS_INT_CYCLE_55       0x0E
#define TSL2591_PRST_ALS_INT_CYCLE_60       0x0F
#define TSL2591_PRST_ALS_INT_CYCLE_MAX      (BIT(4) - 1)

/* TSL2591 PID register mask */
#define TSL2591_PACKAGE_ID_MASK  GENMASK(5, 4)

/* TSL2591 ID register mask */
#define TSL2591_DEVICE_ID_MASK   GENMASK(7, 0)

/* TSL2591 status register masks */
#define TSL2591_STS_ALS_VALID_MASK   BIT(0)
#define TSL2591_STS_ALS_INT_MASK     BIT(4)
#define TSL2591_STS_NPERS_INT_MASK   BIT(5)
#define TSL2591_STS_VAL_HIGH_MASK    BIT(0)

/* TSL2591 constant values */
#define TSL2591_PACKAGE_ID_VAL  0x00
#define TSL2591_DEVICE_ID_VAL   0x50

/* Power off suspend delay time MS */
#define TSL2591_POWER_OFF_DELAY_MS   2000

/* TSL2591 default values */
#define TSL2591_DEFAULT_ALS_INT_TIME          TSL2591_CTRL_ALS_INTEGRATION_300MS
#define TSL2591_DEFAULT_ALS_GAIN              TSL2591_CTRL_ALS_MED_GAIN
#define TSL2591_DEFAULT_ALS_PERSIST           TSL2591_PRST_ALS_INT_CYCLE_ANY
#define TSL2591_DEFAULT_ALS_LOWER_THRESH      100
#define TSL2591_DEFAULT_ALS_UPPER_THRESH      1500

/* TSL2591 number of data registers */
#define TSL2591_NUM_DATA_REGISTERS     4

/* TSL2591 number of valid status reads on ADC complete */
#define TSL2591_ALS_STS_VALID_COUNT    10

/* TSL2591 delay period between polls when checking for ALS valid flag */
#define TSL2591_DELAY_PERIOD_US        10000

/* TSL2591 maximum values */
#define TSL2591_MAX_ALS_INT_TIME_MS    600
#define TSL2591_ALS_MAX_VALUE	       (BIT(16) - 1)

/*
 * LUX calculations;
 * AGAIN values from Adafruit's TSL2591 Arduino library
 * https://github.com/adafruit/Adafruit_TSL2591_Library
 */
#define TSL2591_CTRL_ALS_LOW_GAIN_MULTIPLIER   1
#define TSL2591_CTRL_ALS_MED_GAIN_MULTIPLIER   25
#define TSL2591_CTRL_ALS_HIGH_GAIN_MULTIPLIER  428
#define TSL2591_CTRL_ALS_MAX_GAIN_MULTIPLIER   9876
#define TSL2591_LUX_COEFFICIENT                408

struct tsl2591_als_settings {
	u16 als_lower_thresh;
	u16 als_upper_thresh;
	u8 als_int_time;
	u8 als_persist;
	u8 als_gain;
};

struct tsl2591_chip {
	struct tsl2591_als_settings als_settings;
	struct i2c_client *client;
	/*
	 * Keep als_settings in sync with hardware state
	 * and ensure multiple readers are serialized.
	 */
	struct mutex als_mutex;
	bool events_enabled;
};

/*
 * Period table is ALS persist cycle x integration time setting
 * Integration times: 100ms, 200ms, 300ms, 400ms, 500ms, 600ms
 * ALS cycles: 1, 2, 3, 5, 10, 20, 25, 30, 35, 40, 45, 50, 55, 60
 */
static const char * const tsl2591_als_period_list[] = {
	"0.1 0.2 0.3 0.5 1.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0",
	"0.2 0.4 0.6 1.0 2.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0",
	"0.3 0.6 0.9 1.5 3.0 6.0 7.5 9.0 10.5 12.0 13.5 15.0 16.5 18.0",
	"0.4 0.8 1.2 2.0 4.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0",
	"0.5 1.0 1.5 2.5 5.0 10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0",
	"0.6 1.2 1.8 3.0 6.0 12.0 15.0 18.0 21.0 24.0 27.0 30.0 33.0 36.0",
};

static const int tsl2591_int_time_available[] = {
	1, 2, 3, 4, 5, 6,
};

static const int tsl2591_calibscale_available[] = {
	1, 25, 428, 9876,
};

static int tsl2591_set_als_lower_threshold(struct tsl2591_chip *chip,
					   u16 als_lower_threshold);
static int tsl2591_set_als_upper_threshold(struct tsl2591_chip *chip,
					   u16 als_upper_threshold);

static int tsl2591_gain_to_multiplier(const u8 als_gain)
{
	switch (als_gain) {
	case TSL2591_CTRL_ALS_LOW_GAIN:
		return TSL2591_CTRL_ALS_LOW_GAIN_MULTIPLIER;
	case TSL2591_CTRL_ALS_MED_GAIN:
		return TSL2591_CTRL_ALS_MED_GAIN_MULTIPLIER;
	case TSL2591_CTRL_ALS_HIGH_GAIN:
		return TSL2591_CTRL_ALS_HIGH_GAIN_MULTIPLIER;
	case TSL2591_CTRL_ALS_MAX_GAIN:
		return TSL2591_CTRL_ALS_MAX_GAIN_MULTIPLIER;
	default:
		return -EINVAL;
	}
}

static int tsl2591_multiplier_to_gain(const u32 multiplier)
{
	switch (multiplier) {
	case TSL2591_CTRL_ALS_LOW_GAIN_MULTIPLIER:
		return TSL2591_CTRL_ALS_LOW_GAIN;
	case TSL2591_CTRL_ALS_MED_GAIN_MULTIPLIER:
		return TSL2591_CTRL_ALS_MED_GAIN;
	case TSL2591_CTRL_ALS_HIGH_GAIN_MULTIPLIER:
		return TSL2591_CTRL_ALS_HIGH_GAIN;
	case TSL2591_CTRL_ALS_MAX_GAIN_MULTIPLIER:
		return TSL2591_CTRL_ALS_MAX_GAIN;
	default:
		return -EINVAL;
	}
}

static int tsl2591_persist_cycle_to_lit(const u8 als_persist)
{
	switch (als_persist) {
	case TSL2591_PRST_ALS_INT_CYCLE_ANY:
		return 1;
	case TSL2591_PRST_ALS_INT_CYCLE_2:
		return 2;
	case TSL2591_PRST_ALS_INT_CYCLE_3:
		return 3;
	case TSL2591_PRST_ALS_INT_CYCLE_5:
		return 5;
	case TSL2591_PRST_ALS_INT_CYCLE_10:
		return 10;
	case TSL2591_PRST_ALS_INT_CYCLE_15:
		return 15;
	case TSL2591_PRST_ALS_INT_CYCLE_20:
		return 20;
	case TSL2591_PRST_ALS_INT_CYCLE_25:
		return 25;
	case TSL2591_PRST_ALS_INT_CYCLE_30:
		return 30;
	case TSL2591_PRST_ALS_INT_CYCLE_35:
		return 35;
	case TSL2591_PRST_ALS_INT_CYCLE_40:
		return 40;
	case TSL2591_PRST_ALS_INT_CYCLE_45:
		return 45;
	case TSL2591_PRST_ALS_INT_CYCLE_50:
		return 50;
	case TSL2591_PRST_ALS_INT_CYCLE_55:
		return 55;
	case TSL2591_PRST_ALS_INT_CYCLE_60:
		return 60;
	default:
		return -EINVAL;
	}
}

static int tsl2591_persist_lit_to_cycle(const u8 als_persist)
{
	switch (als_persist) {
	case 1:
		return TSL2591_PRST_ALS_INT_CYCLE_ANY;
	case 2:
		return TSL2591_PRST_ALS_INT_CYCLE_2;
	case 3:
		return TSL2591_PRST_ALS_INT_CYCLE_3;
	case 5:
		return TSL2591_PRST_ALS_INT_CYCLE_5;
	case 10:
		return TSL2591_PRST_ALS_INT_CYCLE_10;
	case 15:
		return TSL2591_PRST_ALS_INT_CYCLE_15;
	case 20:
		return TSL2591_PRST_ALS_INT_CYCLE_20;
	case 25:
		return TSL2591_PRST_ALS_INT_CYCLE_25;
	case 30:
		return TSL2591_PRST_ALS_INT_CYCLE_30;
	case 35:
		return TSL2591_PRST_ALS_INT_CYCLE_35;
	case 40:
		return TSL2591_PRST_ALS_INT_CYCLE_40;
	case 45:
		return TSL2591_PRST_ALS_INT_CYCLE_45;
	case 50:
		return TSL2591_PRST_ALS_INT_CYCLE_50;
	case 55:
		return TSL2591_PRST_ALS_INT_CYCLE_55;
	case 60:
		return TSL2591_PRST_ALS_INT_CYCLE_60;
	default:
		return -EINVAL;
	}
}

static int tsl2591_compatible_int_time(struct tsl2591_chip *chip,
				       const u32 als_integration_time)
{
	switch (als_integration_time) {
	case TSL2591_CTRL_ALS_INTEGRATION_100MS:
	case TSL2591_CTRL_ALS_INTEGRATION_200MS:
	case TSL2591_CTRL_ALS_INTEGRATION_300MS:
	case TSL2591_CTRL_ALS_INTEGRATION_400MS:
	case TSL2591_CTRL_ALS_INTEGRATION_500MS:
	case TSL2591_CTRL_ALS_INTEGRATION_600MS:
		return 0;
	default:
		return -EINVAL;
	}
}

static int tsl2591_als_time_to_fval(const u32 als_integration_time)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(tsl2591_int_time_available); i++) {
		if (als_integration_time == tsl2591_int_time_available[i])
			return TSL2591_SEC_TO_FVAL(als_integration_time);
	}

	return -EINVAL;
}

static int tsl2591_compatible_gain(struct tsl2591_chip *chip, const u8 als_gain)
{
	switch (als_gain) {
	case TSL2591_CTRL_ALS_LOW_GAIN:
	case TSL2591_CTRL_ALS_MED_GAIN:
	case TSL2591_CTRL_ALS_HIGH_GAIN:
	case TSL2591_CTRL_ALS_MAX_GAIN:
		return 0;
	default:
		return -EINVAL;
	}
}

static int tsl2591_compatible_als_persist_cycle(struct tsl2591_chip *chip,
						const u32 als_persist)
{
	switch (als_persist) {
	case TSL2591_PRST_ALS_INT_CYCLE_ANY:
	case TSL2591_PRST_ALS_INT_CYCLE_2:
	case TSL2591_PRST_ALS_INT_CYCLE_3:
	case TSL2591_PRST_ALS_INT_CYCLE_5:
	case TSL2591_PRST_ALS_INT_CYCLE_10:
	case TSL2591_PRST_ALS_INT_CYCLE_15:
	case TSL2591_PRST_ALS_INT_CYCLE_20:
	case TSL2591_PRST_ALS_INT_CYCLE_25:
	case TSL2591_PRST_ALS_INT_CYCLE_30:
	case TSL2591_PRST_ALS_INT_CYCLE_35:
	case TSL2591_PRST_ALS_INT_CYCLE_40:
	case TSL2591_PRST_ALS_INT_CYCLE_45:
	case TSL2591_PRST_ALS_INT_CYCLE_50:
	case TSL2591_PRST_ALS_INT_CYCLE_55:
	case TSL2591_PRST_ALS_INT_CYCLE_60:
		return 0;
	default:
		return -EINVAL;
	}
}

static int tsl2591_check_als_valid(struct i2c_client *client)
{
	int ret;

	ret = i2c_smbus_read_byte_data(client, TSL2591_CMD_NOP | TSL2591_STATUS);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to read register\n");
		return -EINVAL;
	}

	return FIELD_GET(TSL2591_STS_ALS_VALID_MASK, ret);
}

static int tsl2591_wait_adc_complete(struct tsl2591_chip *chip)
{
	struct tsl2591_als_settings settings = chip->als_settings;
	struct i2c_client *client = chip->client;
	int delay;
	int val;
	int ret;

	delay = TSL2591_FVAL_TO_MSEC(settings.als_int_time);
	if (!delay)
		return -EINVAL;

	/*
	 * Sleep for ALS integration time to allow enough time or an ADC read
	 * cycle to complete. Check status after delay for ALS valid.
	 */
	msleep(delay);

	/* Check for status ALS valid flag for up to 100ms */
	ret = readx_poll_timeout(tsl2591_check_als_valid, client,
				 val, val == TSL2591_STS_VAL_HIGH_MASK,
				 TSL2591_DELAY_PERIOD_US,
				 TSL2591_DELAY_PERIOD_US * TSL2591_ALS_STS_VALID_COUNT);
	if (ret)
		dev_err(&client->dev, "Timed out waiting for valid ALS data\n");

	return ret;
}

/*
 * tsl2591_read_channel_data - Reads raw channel data and calculates lux
 *
 * Formula for lux calculation;
 * Derived from Adafruit's TSL2591 library
 * Link: https://github.com/adafruit/Adafruit_TSL2591_Library
 * Counts Per Lux (CPL) = (ATIME_ms * AGAIN) / LUX DF
 * lux = ((C0DATA - C1DATA) * (1 - (C1DATA / C0DATA))) / CPL
 *
 * Scale values to get more representative value of lux i.e.
 * lux = ((C0DATA - C1DATA) * (1000 - ((C1DATA * 1000) / C0DATA))) / CPL
 *
 * Channel 0 = IR + Visible
 * Channel 1 = IR only
 */
static int tsl2591_read_channel_data(struct iio_dev *indio_dev,
				     struct iio_chan_spec const *chan,
				     int *val, int *val2)
{
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	struct tsl2591_als_settings *settings = &chip->als_settings;
	struct i2c_client *client = chip->client;
	u8 als_data[TSL2591_NUM_DATA_REGISTERS];
	int counts_per_lux, int_time_fval, gain_multi, lux;
	u16 als_ch0, als_ch1;
	int ret;

	ret = tsl2591_wait_adc_complete(chip);
	if (ret < 0) {
		dev_err(&client->dev, "No data available. Err: %d\n", ret);
		return ret;
	}

	ret = i2c_smbus_read_i2c_block_data(client,
					    TSL2591_CMD_NOP | TSL2591_C0_DATAL,
					    sizeof(als_data), als_data);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to read data bytes");
		return ret;
	}

	als_ch0 = get_unaligned_le16(&als_data[0]);
	als_ch1 = get_unaligned_le16(&als_data[2]);

	switch (chan->type) {
	case IIO_INTENSITY:
		if (chan->channel2 == IIO_MOD_LIGHT_BOTH)
			*val = als_ch0;
		else if (chan->channel2 == IIO_MOD_LIGHT_IR)
			*val = als_ch1;
		else
			return -EINVAL;
		break;
	case IIO_LIGHT:
		gain_multi = tsl2591_gain_to_multiplier(settings->als_gain);
		if (gain_multi < 0) {
			dev_err(&client->dev, "Invalid multiplier");
			return gain_multi;
		}

		int_time_fval = TSL2591_FVAL_TO_MSEC(settings->als_int_time);
		/* Calculate counts per lux value */
		counts_per_lux = (int_time_fval * gain_multi) / TSL2591_LUX_COEFFICIENT;

		dev_dbg(&client->dev, "Counts Per Lux: %d\n", counts_per_lux);

		/* Calculate lux value */
		lux = ((als_ch0 - als_ch1) *
		       (1000 - ((als_ch1 * 1000) / als_ch0))) / counts_per_lux;

		dev_dbg(&client->dev, "Raw lux calculation: %d\n", lux);

		/* Divide by 1000 to get real lux value before scaling */
		*val = lux / 1000;

		/* Get the decimal part of lux reading */
		*val2 = (lux - (*val * 1000)) * 1000;

		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int tsl2591_set_als_gain_int_time(struct tsl2591_chip *chip)
{
	struct tsl2591_als_settings als_settings = chip->als_settings;
	struct i2c_client *client = chip->client;
	int ret;

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_CONTROL,
					als_settings.als_int_time | als_settings.als_gain);
	if (ret)
		dev_err(&client->dev, "Failed to set als gain & int time\n");

	return ret;
}

static int tsl2591_set_als_lower_threshold(struct tsl2591_chip *chip,
					   u16 als_lower_threshold)
{
	struct tsl2591_als_settings als_settings = chip->als_settings;
	struct i2c_client *client = chip->client;
	u16 als_upper_threshold;
	u8 als_lower_l;
	u8 als_lower_h;
	int ret;

	chip->als_settings.als_lower_thresh = als_lower_threshold;

	/*
	 * Lower threshold should not be greater or equal to upper.
	 * If this is the case, then assert upper threshold to new lower
	 * threshold + 1 to avoid ordering issues when setting thresholds.
	 */
	if (als_lower_threshold >= als_settings.als_upper_thresh) {
		als_upper_threshold = als_lower_threshold + 1;
		tsl2591_set_als_upper_threshold(chip, als_upper_threshold);
	}

	als_lower_l = als_lower_threshold;
	als_lower_h = als_lower_threshold >> 8;

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_AILTL,
					als_lower_l);
	if (ret) {
		dev_err(&client->dev, "Failed to set als lower threshold\n");
		return ret;
	}

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_AILTH,
					als_lower_h);
	if (ret) {
		dev_err(&client->dev, "Failed to set als lower threshold\n");
		return ret;
	}

	return 0;
}

static int tsl2591_set_als_upper_threshold(struct tsl2591_chip *chip,
					   u16 als_upper_threshold)
{
	struct tsl2591_als_settings als_settings = chip->als_settings;
	struct i2c_client *client = chip->client;
	u16 als_lower_threshold;
	u8 als_upper_l;
	u8 als_upper_h;
	int ret;

	if (als_upper_threshold > TSL2591_ALS_MAX_VALUE)
		return -EINVAL;

	chip->als_settings.als_upper_thresh = als_upper_threshold;

	/*
	 * Upper threshold should not be less than lower. If this
	 * is the case, then assert lower threshold to new upper
	 * threshold - 1 to avoid ordering issues when setting thresholds.
	 */
	if (als_upper_threshold < als_settings.als_lower_thresh) {
		als_lower_threshold = als_upper_threshold - 1;
		tsl2591_set_als_lower_threshold(chip, als_lower_threshold);
	}

	als_upper_l = als_upper_threshold;
	als_upper_h = als_upper_threshold >> 8;

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_AIHTL,
					als_upper_l);
	if (ret) {
		dev_err(&client->dev, "Failed to set als upper threshold\n");
		return ret;
	}

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_AIHTH,
					als_upper_h);
	if (ret) {
		dev_err(&client->dev, "Failed to set als upper threshold\n");
		return ret;
	}

	return 0;
}

static int tsl2591_set_als_persist_cycle(struct tsl2591_chip *chip,
					 u8 als_persist)
{
	struct i2c_client *client = chip->client;
	int ret;

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_PERSIST,
					als_persist);
	if (ret)
		dev_err(&client->dev, "Failed to set als persist cycle\n");

	chip->als_settings.als_persist = als_persist;

	return ret;
}

static int tsl2591_set_power_state(struct tsl2591_chip *chip, u8 state)
{
	struct i2c_client *client = chip->client;
	int ret;

	ret = i2c_smbus_write_byte_data(client,
					TSL2591_CMD_NOP | TSL2591_ENABLE,
					state);
	if (ret)
		dev_err(&client->dev,
			"Failed to set the power state to %#04x\n", state);

	return ret;
}

static ssize_t tsl2591_in_illuminance_period_available_show(struct device *dev,
							    struct device_attribute *attr,
							    char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct tsl2591_chip *chip = iio_priv(indio_dev);

	return sysfs_emit(buf, "%s\n",
		       tsl2591_als_period_list[chip->als_settings.als_int_time]);
}

static IIO_DEVICE_ATTR_RO(tsl2591_in_illuminance_period_available, 0);

static struct attribute *tsl2591_event_attrs_ctrl[] = {
	&iio_dev_attr_tsl2591_in_illuminance_period_available.dev_attr.attr,
	NULL
};

static const struct attribute_group tsl2591_event_attribute_group = {
	.attrs = tsl2591_event_attrs_ctrl,
};

static const struct iio_event_spec tsl2591_events[] = {
	{
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_RISING,
		.mask_separate = BIT(IIO_EV_INFO_VALUE),
	}, {
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_FALLING,
		.mask_separate = BIT(IIO_EV_INFO_VALUE),
	}, {
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_EITHER,
		.mask_separate = BIT(IIO_EV_INFO_PERIOD) |
				BIT(IIO_EV_INFO_ENABLE),
	},
};

static const struct iio_chan_spec tsl2591_channels[] = {
	{
		.type = IIO_INTENSITY,
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_IR,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
						     BIT(IIO_CHAN_INFO_CALIBSCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) |
					   BIT(IIO_CHAN_INFO_CALIBSCALE)
	},
	{
		.type = IIO_INTENSITY,
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_BOTH,
		.event_spec = tsl2591_events,
		.num_event_specs = ARRAY_SIZE(tsl2591_events),
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
						     BIT(IIO_CHAN_INFO_CALIBSCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) |
					   BIT(IIO_CHAN_INFO_CALIBSCALE)
	},
	{
		.type = IIO_LIGHT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
						     BIT(IIO_CHAN_INFO_CALIBSCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) |
					   BIT(IIO_CHAN_INFO_CALIBSCALE)
	},
};

static int tsl2591_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long mask)
{
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	struct i2c_client *client = chip->client;
	int ret;

	pm_runtime_get_sync(&client->dev);

	mutex_lock(&chip->als_mutex);

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (chan->type != IIO_INTENSITY) {
			ret = -EINVAL;
			goto err_unlock;
		}

		ret = tsl2591_read_channel_data(indio_dev, chan, val, val2);
		if (ret < 0)
			goto err_unlock;

		ret = IIO_VAL_INT;
		break;
	case IIO_CHAN_INFO_PROCESSED:
		if (chan->type != IIO_LIGHT) {
			ret = -EINVAL;
			goto err_unlock;
		}

		ret = tsl2591_read_channel_data(indio_dev, chan, val, val2);
		if (ret < 0)
			break;

		ret = IIO_VAL_INT_PLUS_MICRO;
		break;
	case IIO_CHAN_INFO_INT_TIME:
		if (chan->type != IIO_INTENSITY) {
			ret = -EINVAL;
			goto err_unlock;
		}

		*val = TSL2591_FVAL_TO_SEC(chip->als_settings.als_int_time);
		ret = IIO_VAL_INT;
		break;
	case IIO_CHAN_INFO_CALIBSCALE:
		if (chan->type != IIO_INTENSITY) {
			ret = -EINVAL;
			goto err_unlock;
		}

		*val = tsl2591_gain_to_multiplier(chip->als_settings.als_gain);
		ret = IIO_VAL_INT;
		break;
	default:
		ret = -EINVAL;
		break;
	}

err_unlock:
	mutex_unlock(&chip->als_mutex);

	pm_runtime_mark_last_busy(&client->dev);
	pm_runtime_put_autosuspend(&client->dev);

	return ret;
}

static int tsl2591_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	int int_time;
	int gain;
	int ret;

	mutex_lock(&chip->als_mutex);

	switch (mask) {
	case IIO_CHAN_INFO_INT_TIME:
		int_time = tsl2591_als_time_to_fval(val);
		if (int_time < 0) {
			ret = int_time;
			goto err_unlock;
		}
		ret = tsl2591_compatible_int_time(chip, int_time);
		if (ret < 0)
			goto err_unlock;

		chip->als_settings.als_int_time = int_time;
		break;
	case IIO_CHAN_INFO_CALIBSCALE:
		gain = tsl2591_multiplier_to_gain(val);
		if (gain < 0) {
			ret = gain;
			goto err_unlock;
		}
		ret = tsl2591_compatible_gain(chip, gain);
		if (ret < 0)
			goto err_unlock;

		chip->als_settings.als_gain = gain;
		break;
	default:
		ret = -EINVAL;
		goto err_unlock;
	}

	ret = tsl2591_set_als_gain_int_time(chip);

err_unlock:
	mutex_unlock(&chip->als_mutex);
	return ret;
}

static int tsl2591_read_available(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_INT_TIME:
		*length = ARRAY_SIZE(tsl2591_int_time_available);
		*vals = tsl2591_int_time_available;
		*type = IIO_VAL_INT;
		return IIO_AVAIL_LIST;

	case IIO_CHAN_INFO_CALIBSCALE:
		*length = ARRAY_SIZE(tsl2591_calibscale_available);
		*vals = tsl2591_calibscale_available;
		*type = IIO_VAL_INT;
		return IIO_AVAIL_LIST;
	default:
		return -EINVAL;
	}
}

static int tsl2591_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 tsl2591_chip *chip = iio_priv(indio_dev);
	struct i2c_client *client = chip->client;
	int als_persist, int_time, period;
	int ret;

	mutex_lock(&chip->als_mutex);

	switch (info) {
	case IIO_EV_INFO_VALUE:
		switch (dir) {
		case IIO_EV_DIR_RISING:
			*val = chip->als_settings.als_upper_thresh;
			break;
		case IIO_EV_DIR_FALLING:
			*val = chip->als_settings.als_lower_thresh;
			break;
		default:
			ret = -EINVAL;
			goto err_unlock;
		}
		ret = IIO_VAL_INT;
		break;
	case IIO_EV_INFO_PERIOD:
		ret = i2c_smbus_read_byte_data(client,
					       TSL2591_CMD_NOP | TSL2591_PERSIST);
		if (ret <= 0 || ret > TSL2591_PRST_ALS_INT_CYCLE_MAX)
			goto err_unlock;

		als_persist = tsl2591_persist_cycle_to_lit(ret);
		int_time = TSL2591_FVAL_TO_MSEC(chip->als_settings.als_int_time);
		period = als_persist * (int_time * MSEC_PER_SEC);

		*val = period / USEC_PER_SEC;
		*val2 = period % USEC_PER_SEC;

		ret = IIO_VAL_INT_PLUS_MICRO;
		break;
	default:
		ret = -EINVAL;
		break;
	}

err_unlock:
	mutex_unlock(&chip->als_mutex);
	return ret;
}

static int tsl2591_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 tsl2591_chip *chip = iio_priv(indio_dev);
	int period, int_time, als_persist;
	int ret;

	if (val < 0 || val2 < 0)
		return -EINVAL;

	mutex_lock(&chip->als_mutex);

	switch (info) {
	case IIO_EV_INFO_VALUE:
		if (val > TSL2591_ALS_MAX_VALUE) {
			ret = -EINVAL;
			goto err_unlock;
		}

		switch (dir) {
		case IIO_EV_DIR_RISING:
			ret = tsl2591_set_als_upper_threshold(chip, val);
			if (ret < 0)
				goto err_unlock;
			break;
		case IIO_EV_DIR_FALLING:
			ret = tsl2591_set_als_lower_threshold(chip, val);
			if (ret < 0)
				goto err_unlock;
			break;
		default:
			ret = -EINVAL;
			goto err_unlock;
		}
		break;
	case IIO_EV_INFO_PERIOD:
		int_time = TSL2591_FVAL_TO_MSEC(chip->als_settings.als_int_time);

		period = ((val * MSEC_PER_SEC) +
			 (val2 / MSEC_PER_SEC)) / int_time;

		als_persist = tsl2591_persist_lit_to_cycle(period);
		if (als_persist < 0) {
			ret = -EINVAL;
			goto err_unlock;
		}

		ret = tsl2591_compatible_als_persist_cycle(chip, als_persist);
		if (ret < 0)
			goto err_unlock;

		ret = tsl2591_set_als_persist_cycle(chip, als_persist);
		if (ret < 0)
			goto err_unlock;
		break;
	default:
		ret = -EINVAL;
		break;
	}

err_unlock:
	mutex_unlock(&chip->als_mutex);
	return ret;
}

static int tsl2591_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 tsl2591_chip *chip = iio_priv(indio_dev);

	return chip->events_enabled;
}

static int tsl2591_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 tsl2591_chip *chip = iio_priv(indio_dev);
	struct i2c_client *client = chip->client;

	if (state && !chip->events_enabled) {
		chip->events_enabled = true;
		pm_runtime_get_sync(&client->dev);
	} else if (!state && chip->events_enabled) {
		chip->events_enabled = false;
		pm_runtime_mark_last_busy(&client->dev);
		pm_runtime_put_autosuspend(&client->dev);
	}

	return 0;
}

static const struct iio_info tsl2591_info = {
	.event_attrs = &tsl2591_event_attribute_group,
	.read_raw = tsl2591_read_raw,
	.write_raw = tsl2591_write_raw,
	.read_avail = tsl2591_read_available,
	.read_event_value = tsl2591_read_event_value,
	.write_event_value = tsl2591_write_event_value,
	.read_event_config = tsl2591_read_event_config,
	.write_event_config = tsl2591_write_event_config,
};

static const struct iio_info tsl2591_info_no_irq = {
	.read_raw = tsl2591_read_raw,
	.write_raw = tsl2591_write_raw,
	.read_avail = tsl2591_read_available,
};

static int tsl2591_suspend(struct device *dev)
{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	int ret;

	mutex_lock(&chip->als_mutex);
	ret = tsl2591_set_power_state(chip, TSL2591_PWR_OFF);
	mutex_unlock(&chip->als_mutex);

	return ret;
}

static int tsl2591_resume(struct device *dev)
{
	int power_state = TSL2591_PWR_ON | TSL2591_ENABLE_ALS;
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	int ret;

	if (chip->events_enabled)
		power_state |= TSL2591_ENABLE_ALS_INT;

	mutex_lock(&chip->als_mutex);
	ret = tsl2591_set_power_state(chip, power_state);
	mutex_unlock(&chip->als_mutex);

	return ret;
}

static DEFINE_RUNTIME_DEV_PM_OPS(tsl2591_pm_ops, tsl2591_suspend,
				 tsl2591_resume, NULL);

static irqreturn_t tsl2591_event_handler(int irq, void *private)
{
	struct iio_dev *dev_info = private;
	struct tsl2591_chip *chip = iio_priv(dev_info);
	struct i2c_client *client = chip->client;

	if (!chip->events_enabled)
		return IRQ_NONE;

	iio_push_event(dev_info,
		       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
					    IIO_EV_TYPE_THRESH,
					    IIO_EV_DIR_EITHER),
					    iio_get_time_ns(dev_info));

	/* Clear ALS irq */
	i2c_smbus_write_byte(client, TSL2591_CMD_SF_CALS_NPI);

	return IRQ_HANDLED;
}

static int tsl2591_load_defaults(struct tsl2591_chip *chip)
{
	int ret;

	chip->als_settings.als_int_time = TSL2591_DEFAULT_ALS_INT_TIME;
	chip->als_settings.als_gain = TSL2591_DEFAULT_ALS_GAIN;
	chip->als_settings.als_lower_thresh = TSL2591_DEFAULT_ALS_LOWER_THRESH;
	chip->als_settings.als_upper_thresh = TSL2591_DEFAULT_ALS_UPPER_THRESH;

	ret = tsl2591_set_als_gain_int_time(chip);
	if (ret < 0)
		return ret;

	ret = tsl2591_set_als_persist_cycle(chip, TSL2591_DEFAULT_ALS_PERSIST);
	if (ret < 0)
		return ret;

	ret = tsl2591_set_als_lower_threshold(chip, TSL2591_DEFAULT_ALS_LOWER_THRESH);
	if (ret < 0)
		return ret;

	ret = tsl2591_set_als_upper_threshold(chip, TSL2591_DEFAULT_ALS_UPPER_THRESH);
	if (ret < 0)
		return ret;

	return 0;
}

static void tsl2591_chip_off(void *data)
{
	struct iio_dev *indio_dev = data;
	struct tsl2591_chip *chip = iio_priv(indio_dev);
	struct i2c_client *client = chip->client;

	pm_runtime_disable(&client->dev);
	pm_runtime_set_suspended(&client->dev);
	pm_runtime_put_noidle(&client->dev);

	tsl2591_set_power_state(chip, TSL2591_PWR_OFF);
}

static int tsl2591_probe(struct i2c_client *client)
{
	struct tsl2591_chip *chip;
	struct iio_dev *indio_dev;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
		dev_err(&client->dev,
			"I2C smbus byte data functionality is not supported\n");
		return -EOPNOTSUPP;
	}

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
	if (!indio_dev)
		return -ENOMEM;

	chip = iio_priv(indio_dev);
	chip->client = client;
	i2c_set_clientdata(client, indio_dev);

	if (client->irq) {
		ret = devm_request_threaded_irq(&client->dev, client->irq,
						NULL, tsl2591_event_handler,
						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
						"tsl2591_irq", indio_dev);
		if (ret) {
			dev_err_probe(&client->dev, ret, "IRQ request error\n");
			return -EINVAL;
		}
		indio_dev->info = &tsl2591_info;
	} else {
		indio_dev->info = &tsl2591_info_no_irq;
	}

	mutex_init(&chip->als_mutex);

	ret = i2c_smbus_read_byte_data(client,
				       TSL2591_CMD_NOP | TSL2591_DEVICE_ID);
	if (ret < 0) {
		dev_err(&client->dev,
			"Failed to read the device ID register\n");
		return ret;
	}
	ret = FIELD_GET(TSL2591_DEVICE_ID_MASK, ret);
	if (ret != TSL2591_DEVICE_ID_VAL) {
		dev_err(&client->dev, "Device ID: %#04x unknown\n", ret);
		return -EINVAL;
	}

	indio_dev->channels = tsl2591_channels;
	indio_dev->num_channels = ARRAY_SIZE(tsl2591_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->name = chip->client->name;
	chip->events_enabled = false;

	pm_runtime_enable(&client->dev);
	pm_runtime_set_autosuspend_delay(&client->dev,
					 TSL2591_POWER_OFF_DELAY_MS);
	pm_runtime_use_autosuspend(&client->dev);

	/*
	 * Add chip off to automatically managed path and disable runtime
	 * power management. This ensures that the chip power management
	 * is handled correctly on driver remove. tsl2591_chip_off() must be
	 * added to the managed path after pm runtime is enabled and before
	 * any error exit paths are met to ensure we're not left in a state
	 * of pm runtime not being disabled properly.
	 */
	ret = devm_add_action_or_reset(&client->dev, tsl2591_chip_off,
				       indio_dev);
	if (ret < 0)
		return -EINVAL;

	ret = tsl2591_load_defaults(chip);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to load sensor defaults\n");
		return -EINVAL;
	}

	ret = i2c_smbus_write_byte(client, TSL2591_CMD_SF_CALS_NPI);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to clear als irq\n");
		return -EINVAL;
	}

	return devm_iio_device_register(&client->dev, indio_dev);
}

static const struct of_device_id tsl2591_of_match[] = {
	{ .compatible = "amstaos,tsl2591"},
	{}
};
MODULE_DEVICE_TABLE(of, tsl2591_of_match);

static struct i2c_driver tsl2591_driver = {
	.driver = {
		.name = "tsl2591",
		.pm = pm_ptr(&tsl2591_pm_ops),
		.of_match_table = tsl2591_of_match,
	},
	.probe = tsl2591_probe
};
module_i2c_driver(tsl2591_driver);

MODULE_AUTHOR("Joe Sandom <joe.g.sandom@gmail.com>");
MODULE_DESCRIPTION("TAOS tsl2591 ambient light sensor driver");
MODULE_LICENSE("GPL");