aboutsummaryrefslogtreecommitdiff
path: root/drivers/iio/light/si1133.c
blob: c280b41950036a57b32db6a75e7acae81fb7eb68 (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
// SPDX-License-Identifier: GPL-2.0+
/*
 * si1133.c - Support for Silabs SI1133 combined ambient
 * light and UV index sensors
 *
 * Copyright 2018 Maxime Roussin-Belanger <maxime.roussinbelanger@gmail.com>
 */

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/regmap.h>

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

#include <linux/util_macros.h>

#include <asm/unaligned.h>

#define SI1133_REG_PART_ID		0x00
#define SI1133_REG_REV_ID		0x01
#define SI1133_REG_MFR_ID		0x02
#define SI1133_REG_INFO0		0x03
#define SI1133_REG_INFO1		0x04

#define SI1133_PART_ID			0x33

#define SI1133_REG_HOSTIN0		0x0A
#define SI1133_REG_COMMAND		0x0B
#define SI1133_REG_IRQ_ENABLE		0x0F
#define SI1133_REG_RESPONSE1		0x10
#define SI1133_REG_RESPONSE0		0x11
#define SI1133_REG_IRQ_STATUS		0x12
#define SI1133_REG_MEAS_RATE		0x1A

#define SI1133_IRQ_CHANNEL_ENABLE	0xF

#define SI1133_CMD_RESET_CTR		0x00
#define SI1133_CMD_RESET_SW		0x01
#define SI1133_CMD_FORCE		0x11
#define SI1133_CMD_START_AUTONOMOUS	0x13
#define SI1133_CMD_PARAM_SET		0x80
#define SI1133_CMD_PARAM_QUERY		0x40
#define SI1133_CMD_PARAM_MASK		0x3F

#define SI1133_CMD_ERR_MASK		BIT(4)
#define SI1133_CMD_SEQ_MASK		0xF
#define SI1133_MAX_CMD_CTR		0xF

#define SI1133_PARAM_REG_CHAN_LIST	0x01
#define SI1133_PARAM_REG_ADCCONFIG(x)	((x) * 4) + 2
#define SI1133_PARAM_REG_ADCSENS(x)	((x) * 4) + 3
#define SI1133_PARAM_REG_ADCPOST(x)	((x) * 4) + 4

#define SI1133_ADCMUX_MASK 0x1F

#define SI1133_ADCCONFIG_DECIM_RATE(x)	(x) << 5

#define SI1133_ADCSENS_SCALE_MASK 0x70
#define SI1133_ADCSENS_SCALE_SHIFT 4
#define SI1133_ADCSENS_HSIG_MASK BIT(7)
#define SI1133_ADCSENS_HSIG_SHIFT 7
#define SI1133_ADCSENS_HW_GAIN_MASK 0xF
#define SI1133_ADCSENS_NB_MEAS(x)	fls(x) << SI1133_ADCSENS_SCALE_SHIFT

#define SI1133_ADCPOST_24BIT_EN BIT(6)
#define SI1133_ADCPOST_POSTSHIFT_BITQTY(x) (x & GENMASK(2, 0)) << 3

#define SI1133_PARAM_ADCMUX_SMALL_IR	0x0
#define SI1133_PARAM_ADCMUX_MED_IR	0x1
#define SI1133_PARAM_ADCMUX_LARGE_IR	0x2
#define SI1133_PARAM_ADCMUX_WHITE	0xB
#define SI1133_PARAM_ADCMUX_LARGE_WHITE	0xD
#define SI1133_PARAM_ADCMUX_UV		0x18
#define SI1133_PARAM_ADCMUX_UV_DEEP	0x19

#define SI1133_ERR_INVALID_CMD		0x0
#define SI1133_ERR_INVALID_LOCATION_CMD 0x1
#define SI1133_ERR_SATURATION_ADC_OR_OVERFLOW_ACCUMULATION 0x2
#define SI1133_ERR_OUTPUT_BUFFER_OVERFLOW 0x3

#define SI1133_COMPLETION_TIMEOUT_MS	500

#define SI1133_CMD_MINSLEEP_US_LOW	5000
#define SI1133_CMD_MINSLEEP_US_HIGH	7500
#define SI1133_CMD_TIMEOUT_MS		25
#define SI1133_CMD_LUX_TIMEOUT_MS	5000
#define SI1133_CMD_TIMEOUT_US		SI1133_CMD_TIMEOUT_MS * 1000

#define SI1133_REG_HOSTOUT(x)		(x) + 0x13

#define SI1133_MEASUREMENT_FREQUENCY 1250

#define SI1133_X_ORDER_MASK            0x0070
#define SI1133_Y_ORDER_MASK            0x0007
#define si1133_get_x_order(m)          ((m) & SI1133_X_ORDER_MASK) >> 4
#define si1133_get_y_order(m)          ((m) & SI1133_Y_ORDER_MASK)

#define SI1133_LUX_ADC_MASK		0xE
#define SI1133_ADC_THRESHOLD		16000
#define SI1133_INPUT_FRACTION_HIGH	7
#define SI1133_INPUT_FRACTION_LOW	15
#define SI1133_LUX_OUTPUT_FRACTION	12
#define SI1133_LUX_BUFFER_SIZE		9
#define SI1133_MEASURE_BUFFER_SIZE	3

static const int si1133_scale_available[] = {
	1, 2, 4, 8, 16, 32, 64, 128};

static IIO_CONST_ATTR(scale_available, "1 2 4 8 16 32 64 128");

static IIO_CONST_ATTR_INT_TIME_AVAIL("0.0244 0.0488 0.0975 0.195 0.390 0.780 "
				     "1.560 3.120 6.24 12.48 25.0 50.0");

/* A.K.A. HW_GAIN in datasheet */
enum si1133_int_time {
	    _24_4_us = 0,
	    _48_8_us = 1,
	    _97_5_us = 2,
	   _195_0_us = 3,
	   _390_0_us = 4,
	   _780_0_us = 5,
	 _1_560_0_us = 6,
	 _3_120_0_us = 7,
	 _6_240_0_us = 8,
	_12_480_0_us = 9,
	_25_ms = 10,
	_50_ms = 11,
};

/* Integration time in milliseconds, nanoseconds */
static const int si1133_int_time_table[][2] = {
	[_24_4_us] = {0, 24400},
	[_48_8_us] = {0, 48800},
	[_97_5_us] = {0, 97500},
	[_195_0_us] = {0, 195000},
	[_390_0_us] = {0, 390000},
	[_780_0_us] = {0, 780000},
	[_1_560_0_us] = {1, 560000},
	[_3_120_0_us] = {3, 120000},
	[_6_240_0_us] = {6, 240000},
	[_12_480_0_us] = {12, 480000},
	[_25_ms] = {25, 000000},
	[_50_ms] = {50, 000000},
};

static const struct regmap_range si1133_reg_ranges[] = {
	regmap_reg_range(0x00, 0x02),
	regmap_reg_range(0x0A, 0x0B),
	regmap_reg_range(0x0F, 0x0F),
	regmap_reg_range(0x10, 0x12),
	regmap_reg_range(0x13, 0x2C),
};

static const struct regmap_range si1133_reg_ro_ranges[] = {
	regmap_reg_range(0x00, 0x02),
	regmap_reg_range(0x10, 0x2C),
};

static const struct regmap_range si1133_precious_ranges[] = {
	regmap_reg_range(0x12, 0x12),
};

static const struct regmap_access_table si1133_write_ranges_table = {
	.yes_ranges	= si1133_reg_ranges,
	.n_yes_ranges	= ARRAY_SIZE(si1133_reg_ranges),
	.no_ranges	= si1133_reg_ro_ranges,
	.n_no_ranges	= ARRAY_SIZE(si1133_reg_ro_ranges),
};

static const struct regmap_access_table si1133_read_ranges_table = {
	.yes_ranges	= si1133_reg_ranges,
	.n_yes_ranges	= ARRAY_SIZE(si1133_reg_ranges),
};

static const struct regmap_access_table si1133_precious_table = {
	.yes_ranges	= si1133_precious_ranges,
	.n_yes_ranges	= ARRAY_SIZE(si1133_precious_ranges),
};

static const struct regmap_config si1133_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = 0x2C,

	.wr_table = &si1133_write_ranges_table,
	.rd_table = &si1133_read_ranges_table,

	.precious_table = &si1133_precious_table,
};

struct si1133_data {
	struct regmap *regmap;
	struct i2c_client *client;

	/* Lock protecting one command at a time can be processed */
	struct mutex mutex;

	int rsp_seq;
	u8 scan_mask;
	u8 adc_sens[6];
	u8 adc_config[6];

	struct completion completion;
};

struct si1133_coeff {
	s16 info;
	u16 mag;
};

struct si1133_lux_coeff {
	struct si1133_coeff coeff_high[4];
	struct si1133_coeff coeff_low[9];
};

static const struct si1133_lux_coeff lux_coeff = {
	{
		{  0,   209},
		{ 1665,  93},
		{ 2064,  65},
		{-2671, 234}
	},
	{
		{    0,     0},
		{ 1921, 29053},
		{-1022, 36363},
		{ 2320, 20789},
		{ -367, 57909},
		{-1774, 38240},
		{ -608, 46775},
		{-1503, 51831},
		{-1886, 58928}
	}
};

static int si1133_calculate_polynomial_inner(s32 input, u8 fraction, u16 mag,
					     s8 shift)
{
	return ((input << fraction) / mag) << shift;
}

static int si1133_calculate_output(s32 x, s32 y, u8 x_order, u8 y_order,
				   u8 input_fraction, s8 sign,
				   const struct si1133_coeff *coeffs)
{
	s8 shift;
	int x1 = 1;
	int x2 = 1;
	int y1 = 1;
	int y2 = 1;

	shift = ((u16)coeffs->info & 0xFF00) >> 8;
	shift ^= 0xFF;
	shift += 1;
	shift = -shift;

	if (x_order > 0) {
		x1 = si1133_calculate_polynomial_inner(x, input_fraction,
						       coeffs->mag, shift);
		if (x_order > 1)
			x2 = x1;
	}

	if (y_order > 0) {
		y1 = si1133_calculate_polynomial_inner(y, input_fraction,
						       coeffs->mag, shift);
		if (y_order > 1)
			y2 = y1;
	}

	return sign * x1 * x2 * y1 * y2;
}

/*
 * The algorithm is from:
 * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00716
 */
static int si1133_calc_polynomial(s32 x, s32 y, u8 input_fraction, u8 num_coeff,
				  const struct si1133_coeff *coeffs)
{
	u8 x_order, y_order;
	u8 counter;
	s8 sign;
	int output = 0;

	for (counter = 0; counter < num_coeff; counter++) {
		if (coeffs->info < 0)
			sign = -1;
		else
			sign = 1;

		x_order = si1133_get_x_order(coeffs->info);
		y_order = si1133_get_y_order(coeffs->info);

		if ((x_order == 0) && (y_order == 0))
			output +=
			       sign * coeffs->mag << SI1133_LUX_OUTPUT_FRACTION;
		else
			output += si1133_calculate_output(x, y, x_order,
							  y_order,
							  input_fraction, sign,
							  coeffs);
		coeffs++;
	}

	return abs(output);
}

static int si1133_cmd_reset_sw(struct si1133_data *data)
{
	struct device *dev = &data->client->dev;
	unsigned int resp;
	unsigned long timeout;
	int err;

	err = regmap_write(data->regmap, SI1133_REG_COMMAND,
			   SI1133_CMD_RESET_SW);
	if (err)
		return err;

	timeout = jiffies + msecs_to_jiffies(SI1133_CMD_TIMEOUT_MS);
	while (true) {
		err = regmap_read(data->regmap, SI1133_REG_RESPONSE0, &resp);
		if (err == -ENXIO) {
			usleep_range(SI1133_CMD_MINSLEEP_US_LOW,
				     SI1133_CMD_MINSLEEP_US_HIGH);
			continue;
		}

		if ((resp & SI1133_MAX_CMD_CTR) == SI1133_MAX_CMD_CTR)
			break;

		if (time_after(jiffies, timeout)) {
			dev_warn(dev, "Timeout on reset ctr resp: %d\n", resp);
			return -ETIMEDOUT;
		}
	}

	if (!err)
		data->rsp_seq = SI1133_MAX_CMD_CTR;

	return err;
}

static int si1133_parse_response_err(struct device *dev, u32 resp, u8 cmd)
{
	resp &= 0xF;

	switch (resp) {
	case SI1133_ERR_OUTPUT_BUFFER_OVERFLOW:
		dev_warn(dev, "Output buffer overflow: %#02hhx\n", cmd);
		return -EOVERFLOW;
	case SI1133_ERR_SATURATION_ADC_OR_OVERFLOW_ACCUMULATION:
		dev_warn(dev, "Saturation of the ADC or overflow of accumulation: %#02hhx\n",
			 cmd);
		return -EOVERFLOW;
	case SI1133_ERR_INVALID_LOCATION_CMD:
		dev_warn(dev,
			 "Parameter access to an invalid location: %#02hhx\n",
			 cmd);
		return -EINVAL;
	case SI1133_ERR_INVALID_CMD:
		dev_warn(dev, "Invalid command %#02hhx\n", cmd);
		return -EINVAL;
	default:
		dev_warn(dev, "Unknown error %#02hhx\n", cmd);
		return -EINVAL;
	}
}

static int si1133_cmd_reset_counter(struct si1133_data *data)
{
	int err = regmap_write(data->regmap, SI1133_REG_COMMAND,
			       SI1133_CMD_RESET_CTR);
	if (err)
		return err;

	data->rsp_seq = 0;

	return 0;
}

static int si1133_command(struct si1133_data *data, u8 cmd)
{
	struct device *dev = &data->client->dev;
	u32 resp;
	int err;
	int expected_seq;

	mutex_lock(&data->mutex);

	expected_seq = (data->rsp_seq + 1) & SI1133_MAX_CMD_CTR;

	if (cmd == SI1133_CMD_FORCE)
		reinit_completion(&data->completion);

	err = regmap_write(data->regmap, SI1133_REG_COMMAND, cmd);
	if (err) {
		dev_warn(dev, "Failed to write command %#02hhx, ret=%d\n", cmd,
			 err);
		goto out;
	}

	if (cmd == SI1133_CMD_FORCE) {
		/* wait for irq */
		if (!wait_for_completion_timeout(&data->completion,
			msecs_to_jiffies(SI1133_COMPLETION_TIMEOUT_MS))) {
			err = -ETIMEDOUT;
			goto out;
		}
		err = regmap_read(data->regmap, SI1133_REG_RESPONSE0, &resp);
		if (err)
			goto out;
	} else {
		err = regmap_read_poll_timeout(data->regmap,
					       SI1133_REG_RESPONSE0, resp,
					       (resp & SI1133_CMD_SEQ_MASK) ==
					       expected_seq ||
					       (resp & SI1133_CMD_ERR_MASK),
					       SI1133_CMD_MINSLEEP_US_LOW,
					       SI1133_CMD_TIMEOUT_MS * 1000);
		if (err) {
			dev_warn(dev,
				 "Failed to read command %#02hhx, ret=%d\n",
				 cmd, err);
			goto out;
		}
	}

	if (resp & SI1133_CMD_ERR_MASK) {
		err = si1133_parse_response_err(dev, resp, cmd);
		si1133_cmd_reset_counter(data);
	} else {
		data->rsp_seq = expected_seq;
	}

out:
	mutex_unlock(&data->mutex);

	return err;
}

static int si1133_param_set(struct si1133_data *data, u8 param, u32 value)
{
	int err = regmap_write(data->regmap, SI1133_REG_HOSTIN0, value);

	if (err)
		return err;

	return si1133_command(data, SI1133_CMD_PARAM_SET |
			      (param & SI1133_CMD_PARAM_MASK));
}

static int si1133_param_query(struct si1133_data *data, u8 param, u32 *result)
{
	int err = si1133_command(data, SI1133_CMD_PARAM_QUERY |
				 (param & SI1133_CMD_PARAM_MASK));
	if (err)
		return err;

	return regmap_read(data->regmap, SI1133_REG_RESPONSE1, result);
}

#define SI1133_CHANNEL(_ch, _type) \
	.type = _type, \
	.channel = _ch, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | \
		BIT(IIO_CHAN_INFO_SCALE) | \
		BIT(IIO_CHAN_INFO_HARDWAREGAIN), \

static const struct iio_chan_spec si1133_channels[] = {
	{
		.type = IIO_LIGHT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
		.channel = 0,
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_WHITE, IIO_INTENSITY)
		.channel2 = IIO_MOD_LIGHT_BOTH,
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_LARGE_WHITE, IIO_INTENSITY)
		.channel2 = IIO_MOD_LIGHT_BOTH,
		.extend_name = "large",
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_SMALL_IR, IIO_INTENSITY)
		.extend_name = "small",
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_IR,
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_MED_IR, IIO_INTENSITY)
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_IR,
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_LARGE_IR, IIO_INTENSITY)
		.extend_name = "large",
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_IR,
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_UV, IIO_UVINDEX)
	},
	{
		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_UV_DEEP, IIO_UVINDEX)
		.modified = 1,
		.channel2 = IIO_MOD_LIGHT_DUV,
	}
};

static int si1133_get_int_time_index(int milliseconds, int nanoseconds)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(si1133_int_time_table); i++) {
		if (milliseconds == si1133_int_time_table[i][0] &&
		    nanoseconds == si1133_int_time_table[i][1])
			return i;
	}
	return -EINVAL;
}

static int si1133_set_integration_time(struct si1133_data *data, u8 adc,
				       int milliseconds, int nanoseconds)
{
	int index;

	index = si1133_get_int_time_index(milliseconds, nanoseconds);
	if (index < 0)
		return index;

	data->adc_sens[adc] &= 0xF0;
	data->adc_sens[adc] |= index;

	return si1133_param_set(data, SI1133_PARAM_REG_ADCSENS(0),
				data->adc_sens[adc]);
}

static int si1133_set_chlist(struct si1133_data *data, u8 scan_mask)
{
	/* channel list already set, no need to reprogram */
	if (data->scan_mask == scan_mask)
		return 0;

	data->scan_mask = scan_mask;

	return si1133_param_set(data, SI1133_PARAM_REG_CHAN_LIST, scan_mask);
}

static int si1133_chan_set_adcconfig(struct si1133_data *data, u8 adc,
				     u8 adc_config)
{
	int err;

	err = si1133_param_set(data, SI1133_PARAM_REG_ADCCONFIG(adc),
			       adc_config);
	if (err)
		return err;

	data->adc_config[adc] = adc_config;

	return 0;
}

static int si1133_update_adcconfig(struct si1133_data *data, uint8_t adc,
				   u8 mask, u8 shift, u8 value)
{
	u32 adc_config;
	int err;

	err = si1133_param_query(data, SI1133_PARAM_REG_ADCCONFIG(adc),
				 &adc_config);
	if (err)
		return err;

	adc_config &= ~mask;
	adc_config |= (value << shift);

	return si1133_chan_set_adcconfig(data, adc, adc_config);
}

static int si1133_set_adcmux(struct si1133_data *data, u8 adc, u8 mux)
{
	if ((mux & data->adc_config[adc]) == mux)
		return 0; /* mux already set to correct value */

	return si1133_update_adcconfig(data, adc, SI1133_ADCMUX_MASK, 0, mux);
}

static int si1133_force_measurement(struct si1133_data *data)
{
	return si1133_command(data, SI1133_CMD_FORCE);
}

static int si1133_bulk_read(struct si1133_data *data, u8 start_reg, u8 length,
			    u8 *buffer)
{
	int err;

	err = si1133_force_measurement(data);
	if (err)
		return err;

	return regmap_bulk_read(data->regmap, start_reg, buffer, length);
}

static int si1133_measure(struct si1133_data *data,
			  struct iio_chan_spec const *chan,
			  int *val)
{
	int err;

	u8 buffer[SI1133_MEASURE_BUFFER_SIZE];

	err = si1133_set_adcmux(data, 0, chan->channel);
	if (err)
		return err;

	/* Deactivate lux measurements if they were active */
	err = si1133_set_chlist(data, BIT(0));
	if (err)
		return err;

	err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(buffer),
			       buffer);
	if (err)
		return err;

	*val = sign_extend32(get_unaligned_be24(&buffer[0]), 23);

	return err;
}

static irqreturn_t si1133_threaded_irq_handler(int irq, void *private)
{
	struct iio_dev *iio_dev = private;
	struct si1133_data *data = iio_priv(iio_dev);
	u32 irq_status;
	int err;

	err = regmap_read(data->regmap, SI1133_REG_IRQ_STATUS, &irq_status);
	if (err) {
		dev_err_ratelimited(&iio_dev->dev, "Error reading IRQ\n");
		goto out;
	}

	if (irq_status != data->scan_mask)
		return IRQ_NONE;

out:
	complete(&data->completion);

	return IRQ_HANDLED;
}

static int si1133_scale_to_swgain(int scale_integer, int scale_fractional)
{
	scale_integer = find_closest(scale_integer, si1133_scale_available,
				     ARRAY_SIZE(si1133_scale_available));
	if (scale_integer < 0 ||
	    scale_integer > ARRAY_SIZE(si1133_scale_available) ||
	    scale_fractional != 0)
		return -EINVAL;

	return scale_integer;
}

static int si1133_chan_set_adcsens(struct si1133_data *data, u8 adc,
				   u8 adc_sens)
{
	int err;

	err = si1133_param_set(data, SI1133_PARAM_REG_ADCSENS(adc), adc_sens);
	if (err)
		return err;

	data->adc_sens[adc] = adc_sens;

	return 0;
}

static int si1133_update_adcsens(struct si1133_data *data, u8 mask,
				 u8 shift, u8 value)
{
	int err;
	u32 adc_sens;

	err = si1133_param_query(data, SI1133_PARAM_REG_ADCSENS(0),
				 &adc_sens);
	if (err)
		return err;

	adc_sens &= ~mask;
	adc_sens |= (value << shift);

	return si1133_chan_set_adcsens(data, 0, adc_sens);
}

static int si1133_get_lux(struct si1133_data *data, int *val)
{
	int err;
	int lux;
	s32 high_vis;
	s32 low_vis;
	s32 ir;
	u8 buffer[SI1133_LUX_BUFFER_SIZE];

	/* Activate lux channels */
	err = si1133_set_chlist(data, SI1133_LUX_ADC_MASK);
	if (err)
		return err;

	err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0),
			       SI1133_LUX_BUFFER_SIZE, buffer);
	if (err)
		return err;

	high_vis = sign_extend32(get_unaligned_be24(&buffer[0]), 23);

	low_vis = sign_extend32(get_unaligned_be24(&buffer[3]), 23);

	ir = sign_extend32(get_unaligned_be24(&buffer[6]), 23);

	if (high_vis > SI1133_ADC_THRESHOLD || ir > SI1133_ADC_THRESHOLD)
		lux = si1133_calc_polynomial(high_vis, ir,
					     SI1133_INPUT_FRACTION_HIGH,
					     ARRAY_SIZE(lux_coeff.coeff_high),
					     &lux_coeff.coeff_high[0]);
	else
		lux = si1133_calc_polynomial(low_vis, ir,
					     SI1133_INPUT_FRACTION_LOW,
					     ARRAY_SIZE(lux_coeff.coeff_low),
					     &lux_coeff.coeff_low[0]);

	*val = lux >> SI1133_LUX_OUTPUT_FRACTION;

	return err;
}

static int si1133_read_raw(struct iio_dev *iio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long mask)
{
	struct si1133_data *data = iio_priv(iio_dev);
	u8 adc_sens = data->adc_sens[0];
	int err;

	switch (mask) {
	case IIO_CHAN_INFO_PROCESSED:
		switch (chan->type) {
		case IIO_LIGHT:
			err = si1133_get_lux(data, val);
			if (err)
				return err;

			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_RAW:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			err = si1133_measure(data, chan, val);
			if (err)
				return err;

			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_INT_TIME:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			adc_sens &= SI1133_ADCSENS_HW_GAIN_MASK;

			*val = si1133_int_time_table[adc_sens][0];
			*val2 = si1133_int_time_table[adc_sens][1];
			return IIO_VAL_INT_PLUS_MICRO;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_SCALE:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			adc_sens &= SI1133_ADCSENS_SCALE_MASK;
			adc_sens >>= SI1133_ADCSENS_SCALE_SHIFT;

			*val = BIT(adc_sens);

			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_HARDWAREGAIN:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			adc_sens >>= SI1133_ADCSENS_HSIG_SHIFT;

			*val = adc_sens;

			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	default:
		return -EINVAL;
	}
}

static int si1133_write_raw(struct iio_dev *iio_dev,
			    struct iio_chan_spec const *chan,
			    int val, int val2, long mask)
{
	struct si1133_data *data = iio_priv(iio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_SCALE:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			val = si1133_scale_to_swgain(val, val2);
			if (val < 0)
				return val;

			return si1133_update_adcsens(data,
						     SI1133_ADCSENS_SCALE_MASK,
						     SI1133_ADCSENS_SCALE_SHIFT,
						     val);
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_INT_TIME:
		return si1133_set_integration_time(data, 0, val, val2);
	case IIO_CHAN_INFO_HARDWAREGAIN:
		switch (chan->type) {
		case IIO_INTENSITY:
		case IIO_UVINDEX:
			if (val != 0 && val != 1)
				return -EINVAL;

			return si1133_update_adcsens(data,
						     SI1133_ADCSENS_HSIG_MASK,
						     SI1133_ADCSENS_HSIG_SHIFT,
						     val);
		default:
			return -EINVAL;
		}
	default:
		return -EINVAL;
	}
}

static struct attribute *si1133_attributes[] = {
	&iio_const_attr_integration_time_available.dev_attr.attr,
	&iio_const_attr_scale_available.dev_attr.attr,
	NULL,
};

static const struct attribute_group si1133_attribute_group = {
	.attrs = si1133_attributes,
};

static const struct iio_info si1133_info = {
	.read_raw = si1133_read_raw,
	.write_raw = si1133_write_raw,
	.attrs = &si1133_attribute_group,
};

/*
 * si1133_init_lux_channels - Configure 3 different channels(adc) (1,2 and 3)
 * The channel configuration for the lux measurement was taken from :
 * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00578
 *
 * Reserved the channel 0 for the other raw measurements
 */
static int si1133_init_lux_channels(struct si1133_data *data)
{
	int err;

	err = si1133_chan_set_adcconfig(data, 1,
					SI1133_ADCCONFIG_DECIM_RATE(1) |
					SI1133_PARAM_ADCMUX_LARGE_WHITE);
	if (err)
		return err;

	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(1),
			       SI1133_ADCPOST_24BIT_EN |
			       SI1133_ADCPOST_POSTSHIFT_BITQTY(0));
	if (err)
		return err;
	err = si1133_chan_set_adcsens(data, 1, SI1133_ADCSENS_HSIG_MASK |
				      SI1133_ADCSENS_NB_MEAS(64) | _48_8_us);
	if (err)
		return err;

	err = si1133_chan_set_adcconfig(data, 2,
					SI1133_ADCCONFIG_DECIM_RATE(1) |
					SI1133_PARAM_ADCMUX_LARGE_WHITE);
	if (err)
		return err;

	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(2),
			       SI1133_ADCPOST_24BIT_EN |
			       SI1133_ADCPOST_POSTSHIFT_BITQTY(2));
	if (err)
		return err;

	err = si1133_chan_set_adcsens(data, 2, SI1133_ADCSENS_HSIG_MASK |
				      SI1133_ADCSENS_NB_MEAS(1) | _3_120_0_us);
	if (err)
		return err;

	err = si1133_chan_set_adcconfig(data, 3,
					SI1133_ADCCONFIG_DECIM_RATE(1) |
					SI1133_PARAM_ADCMUX_MED_IR);
	if (err)
		return err;

	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(3),
			       SI1133_ADCPOST_24BIT_EN |
			       SI1133_ADCPOST_POSTSHIFT_BITQTY(2));
	if (err)
		return err;

	return  si1133_chan_set_adcsens(data, 3, SI1133_ADCSENS_HSIG_MASK |
					SI1133_ADCSENS_NB_MEAS(64) | _48_8_us);
}

static int si1133_initialize(struct si1133_data *data)
{
	int err;

	err = si1133_cmd_reset_sw(data);
	if (err)
		return err;

	/* Turn off autonomous mode */
	err = si1133_param_set(data, SI1133_REG_MEAS_RATE, 0);
	if (err)
		return err;

	err = si1133_init_lux_channels(data);
	if (err)
		return err;

	return regmap_write(data->regmap, SI1133_REG_IRQ_ENABLE,
			    SI1133_IRQ_CHANNEL_ENABLE);
}

static int si1133_validate_ids(struct iio_dev *iio_dev)
{
	struct si1133_data *data = iio_priv(iio_dev);

	unsigned int part_id, rev_id, mfr_id;
	int err;

	err = regmap_read(data->regmap, SI1133_REG_PART_ID, &part_id);
	if (err)
		return err;

	err = regmap_read(data->regmap, SI1133_REG_REV_ID, &rev_id);
	if (err)
		return err;

	err = regmap_read(data->regmap, SI1133_REG_MFR_ID, &mfr_id);
	if (err)
		return err;

	dev_info(&iio_dev->dev,
		 "Device ID part %#02hhx rev %#02hhx mfr %#02hhx\n",
		 part_id, rev_id, mfr_id);
	if (part_id != SI1133_PART_ID) {
		dev_err(&iio_dev->dev,
			"Part ID mismatch got %#02hhx, expected %#02x\n",
			part_id, SI1133_PART_ID);
		return -ENODEV;
	}

	return 0;
}

static int si1133_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct si1133_data *data;
	struct iio_dev *iio_dev;
	int err;

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

	data = iio_priv(iio_dev);

	init_completion(&data->completion);

	data->regmap = devm_regmap_init_i2c(client, &si1133_regmap_config);
	if (IS_ERR(data->regmap)) {
		err = PTR_ERR(data->regmap);
		dev_err(&client->dev, "Failed to initialise regmap: %d\n", err);
		return err;
	}

	i2c_set_clientdata(client, iio_dev);
	data->client = client;

	iio_dev->name = id->name;
	iio_dev->channels = si1133_channels;
	iio_dev->num_channels = ARRAY_SIZE(si1133_channels);
	iio_dev->info = &si1133_info;
	iio_dev->modes = INDIO_DIRECT_MODE;

	mutex_init(&data->mutex);

	err = si1133_validate_ids(iio_dev);
	if (err)
		return err;

	err = si1133_initialize(data);
	if (err) {
		dev_err(&client->dev,
			"Error when initializing chip: %d\n", err);
		return err;
	}

	if (!client->irq) {
		dev_err(&client->dev,
			"Required interrupt not provided, cannot proceed\n");
		return -EINVAL;
	}

	err = devm_request_threaded_irq(&client->dev, client->irq,
					NULL,
					si1133_threaded_irq_handler,
					IRQF_ONESHOT | IRQF_SHARED,
					client->name, iio_dev);
	if (err) {
		dev_warn(&client->dev, "Request irq %d failed: %i\n",
			 client->irq, err);
		return err;
	}

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

static const struct i2c_device_id si1133_ids[] = {
	{ "si1133", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, si1133_ids);

static struct i2c_driver si1133_driver = {
	.driver = {
	    .name   = "si1133",
	},
	.probe  = si1133_probe,
	.id_table = si1133_ids,
};

module_i2c_driver(si1133_driver);

MODULE_AUTHOR("Maxime Roussin-Belanger <maxime.roussinbelanger@gmail.com>");
MODULE_DESCRIPTION("Silabs SI1133, UV index sensor and ambient light sensor driver");
MODULE_LICENSE("GPL");