summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/nct7904.c
blob: 281c81edabc65740df60c154b4b1e59c4c995fc7 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * nct7904.c - driver for Nuvoton NCT7904D.
 *
 * Copyright (c) 2015 Kontron
 * Author: Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>
 *
 * Copyright (c) 2019 Advantech
 * Author: Amy.Shih <amy.shih@advantech.com.tw>
 */

#include <linux/module.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/hwmon.h>

#define VENDOR_ID_REG		0x7A	/* Any bank */
#define NUVOTON_ID		0x50
#define CHIP_ID_REG		0x7B	/* Any bank */
#define NCT7904_ID		0xC5
#define DEVICE_ID_REG		0x7C	/* Any bank */

#define BANK_SEL_REG		0xFF
#define BANK_0			0x00
#define BANK_1			0x01
#define BANK_2			0x02
#define BANK_3			0x03
#define BANK_4			0x04
#define BANK_MAX		0x04

#define FANIN_MAX		12	/* Counted from 1 */
#define VSEN_MAX		21	/* VSEN1..14, 3VDD, VBAT, V3VSB,
					   LTD (not a voltage), VSEN17..19 */
#define FANCTL_MAX		4	/* Counted from 1 */
#define TCPU_MAX		8	/* Counted from 1 */
#define TEMP_MAX		4	/* Counted from 1 */

#define VT_ADC_CTRL0_REG	0x20	/* Bank 0 */
#define VT_ADC_CTRL1_REG	0x21	/* Bank 0 */
#define VT_ADC_CTRL2_REG	0x22	/* Bank 0 */
#define FANIN_CTRL0_REG		0x24
#define FANIN_CTRL1_REG		0x25
#define DTS_T_CTRL0_REG		0x26
#define DTS_T_CTRL1_REG		0x27
#define VT_ADC_MD_REG		0x2E

#define VSEN1_HV_LL_REG		0x02	/* Bank 1; 2 regs (HV/LV) per sensor */
#define VSEN1_LV_LL_REG		0x03	/* Bank 1; 2 regs (HV/LV) per sensor */
#define VSEN1_HV_HL_REG		0x00	/* Bank 1; 2 regs (HV/LV) per sensor */
#define VSEN1_LV_HL_REG		0x01	/* Bank 1; 2 regs (HV/LV) per sensor */
#define SMI_STS1_REG		0xC1	/* Bank 0; SMI Status Register */
#define SMI_STS3_REG		0xC3	/* Bank 0; SMI Status Register */
#define SMI_STS5_REG		0xC5	/* Bank 0; SMI Status Register */
#define SMI_STS7_REG		0xC7	/* Bank 0; SMI Status Register */
#define SMI_STS8_REG		0xC8	/* Bank 0; SMI Status Register */

#define VSEN1_HV_REG		0x40	/* Bank 0; 2 regs (HV/LV) per sensor */
#define TEMP_CH1_HV_REG		0x42	/* Bank 0; same as VSEN2_HV */
#define LTD_HV_REG		0x62	/* Bank 0; 2 regs in VSEN range */
#define LTD_HV_HL_REG		0x44	/* Bank 1; 1 reg for LTD */
#define LTD_LV_HL_REG		0x45	/* Bank 1; 1 reg for LTD */
#define LTD_HV_LL_REG		0x46	/* Bank 1; 1 reg for LTD */
#define LTD_LV_LL_REG		0x47	/* Bank 1; 1 reg for LTD */
#define TEMP_CH1_CH_REG		0x05	/* Bank 1; 1 reg for LTD */
#define TEMP_CH1_W_REG		0x06	/* Bank 1; 1 reg for LTD */
#define TEMP_CH1_WH_REG		0x07	/* Bank 1; 1 reg for LTD */
#define TEMP_CH1_C_REG		0x04	/* Bank 1; 1 reg per sensor */
#define DTS_T_CPU1_C_REG	0x90	/* Bank 1; 1 reg per sensor */
#define DTS_T_CPU1_CH_REG	0x91	/* Bank 1; 1 reg per sensor */
#define DTS_T_CPU1_W_REG	0x92	/* Bank 1; 1 reg per sensor */
#define DTS_T_CPU1_WH_REG	0x93	/* Bank 1; 1 reg per sensor */
#define FANIN1_HV_REG		0x80	/* Bank 0; 2 regs (HV/LV) per sensor */
#define FANIN1_HV_HL_REG	0x60	/* Bank 1; 2 regs (HV/LV) per sensor */
#define FANIN1_LV_HL_REG	0x61	/* Bank 1; 2 regs (HV/LV) per sensor */
#define T_CPU1_HV_REG		0xA0	/* Bank 0; 2 regs (HV/LV) per sensor */

#define PRTS_REG		0x03	/* Bank 2 */
#define PFE_REG			0x00	/* Bank 2; PECI Function Enable */
#define TSI_CTRL_REG		0x50	/* Bank 2; TSI Control Register */
#define FANCTL1_FMR_REG		0x00	/* Bank 3; 1 reg per channel */
#define FANCTL1_OUT_REG		0x10	/* Bank 3; 1 reg per channel */

#define VOLT_MONITOR_MODE	0x0
#define THERMAL_DIODE_MODE	0x1
#define THERMISTOR_MODE		0x3

#define ENABLE_TSI	BIT(1)

static const unsigned short normal_i2c[] = {
	0x2d, 0x2e, I2C_CLIENT_END
};

struct nct7904_data {
	struct i2c_client *client;
	struct mutex bank_lock;
	int bank_sel;
	u32 fanin_mask;
	u32 vsen_mask;
	u32 tcpu_mask;
	u8 fan_mode[FANCTL_MAX];
	u8 enable_dts;
	u8 has_dts;
	u8 temp_mode; /* 0: TR mode, 1: TD mode */
	u8 fan_alarm[2];
	u8 vsen_alarm[3];
};

/* Access functions */
static int nct7904_bank_lock(struct nct7904_data *data, unsigned int bank)
{
	int ret;

	mutex_lock(&data->bank_lock);
	if (data->bank_sel == bank)
		return 0;
	ret = i2c_smbus_write_byte_data(data->client, BANK_SEL_REG, bank);
	if (ret == 0)
		data->bank_sel = bank;
	else
		data->bank_sel = -1;
	return ret;
}

static inline void nct7904_bank_release(struct nct7904_data *data)
{
	mutex_unlock(&data->bank_lock);
}

/* Read 1-byte register. Returns unsigned reg or -ERRNO on error. */
static int nct7904_read_reg(struct nct7904_data *data,
			    unsigned int bank, unsigned int reg)
{
	struct i2c_client *client = data->client;
	int ret;

	ret = nct7904_bank_lock(data, bank);
	if (ret == 0)
		ret = i2c_smbus_read_byte_data(client, reg);

	nct7904_bank_release(data);
	return ret;
}

/*
 * Read 2-byte register. Returns register in big-endian format or
 * -ERRNO on error.
 */
static int nct7904_read_reg16(struct nct7904_data *data,
			      unsigned int bank, unsigned int reg)
{
	struct i2c_client *client = data->client;
	int ret, hi;

	ret = nct7904_bank_lock(data, bank);
	if (ret == 0) {
		ret = i2c_smbus_read_byte_data(client, reg);
		if (ret >= 0) {
			hi = ret;
			ret = i2c_smbus_read_byte_data(client, reg + 1);
			if (ret >= 0)
				ret |= hi << 8;
		}
	}

	nct7904_bank_release(data);
	return ret;
}

/* Write 1-byte register. Returns 0 or -ERRNO on error. */
static int nct7904_write_reg(struct nct7904_data *data,
			     unsigned int bank, unsigned int reg, u8 val)
{
	struct i2c_client *client = data->client;
	int ret;

	ret = nct7904_bank_lock(data, bank);
	if (ret == 0)
		ret = i2c_smbus_write_byte_data(client, reg, val);

	nct7904_bank_release(data);
	return ret;
}

static int nct7904_read_fan(struct device *dev, u32 attr, int channel,
			    long *val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	unsigned int cnt, rpm;
	int ret;

	switch (attr) {
	case hwmon_fan_input:
		ret = nct7904_read_reg16(data, BANK_0,
					 FANIN1_HV_REG + channel * 2);
		if (ret < 0)
			return ret;
		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
		if (cnt == 0x1fff)
			rpm = 0;
		else
			rpm = 1350000 / cnt;
		*val = rpm;
		return 0;
	case hwmon_fan_min:
		ret = nct7904_read_reg16(data, BANK_1,
					 FANIN1_HV_HL_REG + channel * 2);
		if (ret < 0)
			return ret;
		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
		if (cnt == 0x1fff)
			rpm = 0;
		else
			rpm = 1350000 / cnt;
		*val = rpm;
		return 0;
	case hwmon_fan_alarm:
		ret = nct7904_read_reg(data, BANK_0,
				       SMI_STS5_REG + (channel >> 3));
		if (ret < 0)
			return ret;
		if (!data->fan_alarm[channel >> 3])
			data->fan_alarm[channel >> 3] = ret & 0xff;
		else
			/* If there is new alarm showing up */
			data->fan_alarm[channel >> 3] |= (ret & 0xff);
		*val = (data->fan_alarm[channel >> 3] >> (channel & 0x07)) & 1;
		/* Needs to clean the alarm if alarm existing */
		if (*val)
			data->fan_alarm[channel >> 3] ^= 1 << (channel & 0x07);
		return 0;
	default:
		return -EOPNOTSUPP;
	}
}

static umode_t nct7904_fan_is_visible(const void *_data, u32 attr, int channel)
{
	const struct nct7904_data *data = _data;

	switch (attr) {
	case hwmon_fan_input:
	case hwmon_fan_alarm:
		if (data->fanin_mask & (1 << channel))
			return 0444;
		break;
	case hwmon_fan_min:
		if (data->fanin_mask & (1 << channel))
			return 0644;
		break;
	default:
		break;
	}

	return 0;
}

static u8 nct7904_chan_to_index[] = {
	0,	/* Not used */
	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
	18, 19, 20, 16
};

static int nct7904_read_in(struct device *dev, u32 attr, int channel,
			   long *val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret, volt, index;

	index = nct7904_chan_to_index[channel];

	switch (attr) {
	case hwmon_in_input:
		ret = nct7904_read_reg16(data, BANK_0,
					 VSEN1_HV_REG + index * 2);
		if (ret < 0)
			return ret;
		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
		if (index < 14)
			volt *= 2; /* 0.002V scale */
		else
			volt *= 6; /* 0.006V scale */
		*val = volt;
		return 0;
	case hwmon_in_min:
		ret = nct7904_read_reg16(data, BANK_1,
					 VSEN1_HV_LL_REG + index * 4);
		if (ret < 0)
			return ret;
		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
		if (index < 14)
			volt *= 2; /* 0.002V scale */
		else
			volt *= 6; /* 0.006V scale */
		*val = volt;
		return 0;
	case hwmon_in_max:
		ret = nct7904_read_reg16(data, BANK_1,
					 VSEN1_HV_HL_REG + index * 4);
		if (ret < 0)
			return ret;
		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
		if (index < 14)
			volt *= 2; /* 0.002V scale */
		else
			volt *= 6; /* 0.006V scale */
		*val = volt;
		return 0;
	case hwmon_in_alarm:
		ret = nct7904_read_reg(data, BANK_0,
				       SMI_STS1_REG + (index >> 3));
		if (ret < 0)
			return ret;
		if (!data->vsen_alarm[index >> 3])
			data->vsen_alarm[index >> 3] = ret & 0xff;
		else
			/* If there is new alarm showing up */
			data->vsen_alarm[index >> 3] |= (ret & 0xff);
		*val = (data->vsen_alarm[index >> 3] >> (index & 0x07)) & 1;
		/* Needs to clean the alarm if alarm existing */
		if (*val)
			data->vsen_alarm[index >> 3] ^= 1 << (index & 0x07);
		return 0;
	default:
		return -EOPNOTSUPP;
	}
}

static umode_t nct7904_in_is_visible(const void *_data, u32 attr, int channel)
{
	const struct nct7904_data *data = _data;
	int index = nct7904_chan_to_index[channel];

	switch (attr) {
	case hwmon_in_input:
	case hwmon_in_alarm:
		if (channel > 0 && (data->vsen_mask & BIT(index)))
			return 0444;
		break;
	case hwmon_in_min:
	case hwmon_in_max:
		if (channel > 0 && (data->vsen_mask & BIT(index)))
			return 0644;
		break;
	default:
		break;
	}

	return 0;
}

static int nct7904_read_temp(struct device *dev, u32 attr, int channel,
			     long *val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret, temp;
	unsigned int reg1, reg2, reg3;

	switch (attr) {
	case hwmon_temp_input:
		if (channel == 4)
			ret = nct7904_read_reg16(data, BANK_0, LTD_HV_REG);
		else if (channel < 5)
			ret = nct7904_read_reg16(data, BANK_0,
						 TEMP_CH1_HV_REG + channel * 4);
		else
			ret = nct7904_read_reg16(data, BANK_0,
						 T_CPU1_HV_REG + (channel - 5)
						 * 2);
		if (ret < 0)
			return ret;
		temp = ((ret & 0xff00) >> 5) | (ret & 0x7);
		*val = sign_extend32(temp, 10) * 125;
		return 0;
	case hwmon_temp_alarm:
		if (channel == 4) {
			ret = nct7904_read_reg(data, BANK_0,
					       SMI_STS3_REG);
			if (ret < 0)
				return ret;
			*val = (ret >> 1) & 1;
		} else if (channel < 4) {
			ret = nct7904_read_reg(data, BANK_0,
					       SMI_STS1_REG);
			if (ret < 0)
				return ret;
			*val = (ret >> (((channel * 2) + 1) & 0x07)) & 1;
		} else {
			if ((channel - 5) < 4) {
				ret = nct7904_read_reg(data, BANK_0,
						       SMI_STS7_REG +
						       ((channel - 5) >> 3));
				if (ret < 0)
					return ret;
				*val = (ret >> ((channel - 5) & 0x07)) & 1;
			} else {
				ret = nct7904_read_reg(data, BANK_0,
						       SMI_STS8_REG +
						       ((channel - 5) >> 3));
				if (ret < 0)
					return ret;
				*val = (ret >> (((channel - 5) & 0x07) - 4))
							& 1;
			}
		}
		return 0;
	case hwmon_temp_type:
		if (channel < 5) {
			if ((data->tcpu_mask >> channel) & 0x01) {
				if ((data->temp_mode >> channel) & 0x01)
					*val = 3; /* TD */
				else
					*val = 4; /* TR */
			} else {
				*val = 0;
			}
		} else {
			if ((data->has_dts >> (channel - 5)) & 0x01) {
				if (data->enable_dts & ENABLE_TSI)
					*val = 5; /* TSI */
				else
					*val = 6; /* PECI */
			} else {
				*val = 0;
			}
		}
		return 0;
	case hwmon_temp_max:
		reg1 = LTD_HV_LL_REG;
		reg2 = TEMP_CH1_W_REG;
		reg3 = DTS_T_CPU1_W_REG;
		break;
	case hwmon_temp_max_hyst:
		reg1 = LTD_LV_LL_REG;
		reg2 = TEMP_CH1_WH_REG;
		reg3 = DTS_T_CPU1_WH_REG;
		break;
	case hwmon_temp_crit:
		reg1 = LTD_HV_HL_REG;
		reg2 = TEMP_CH1_C_REG;
		reg3 = DTS_T_CPU1_C_REG;
		break;
	case hwmon_temp_crit_hyst:
		reg1 = LTD_LV_HL_REG;
		reg2 = TEMP_CH1_CH_REG;
		reg3 = DTS_T_CPU1_CH_REG;
		break;
	default:
		return -EOPNOTSUPP;
	}

	if (channel == 4)
		ret = nct7904_read_reg(data, BANK_1, reg1);
	else if (channel < 5)
		ret = nct7904_read_reg(data, BANK_1,
				       reg2 + channel * 8);
	else
		ret = nct7904_read_reg(data, BANK_1,
				       reg3 + (channel - 5) * 4);

	if (ret < 0)
		return ret;
	*val = ret * 1000;
	return 0;
}

static umode_t nct7904_temp_is_visible(const void *_data, u32 attr, int channel)
{
	const struct nct7904_data *data = _data;

	switch (attr) {
	case hwmon_temp_input:
	case hwmon_temp_alarm:
	case hwmon_temp_type:
		if (channel < 5) {
			if (data->tcpu_mask & BIT(channel))
				return 0444;
		} else {
			if (data->has_dts & BIT(channel - 5))
				return 0444;
		}
		break;
	case hwmon_temp_max:
	case hwmon_temp_max_hyst:
	case hwmon_temp_crit:
	case hwmon_temp_crit_hyst:
		if (channel < 5) {
			if (data->tcpu_mask & BIT(channel))
				return 0644;
		} else {
			if (data->has_dts & BIT(channel - 5))
				return 0644;
		}
		break;
	default:
		break;
	}

	return 0;
}

static int nct7904_read_pwm(struct device *dev, u32 attr, int channel,
			    long *val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret;

	switch (attr) {
	case hwmon_pwm_input:
		ret = nct7904_read_reg(data, BANK_3, FANCTL1_OUT_REG + channel);
		if (ret < 0)
			return ret;
		*val = ret;
		return 0;
	case hwmon_pwm_enable:
		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + channel);
		if (ret < 0)
			return ret;

		*val = ret ? 2 : 1;
		return 0;
	default:
		return -EOPNOTSUPP;
	}
}

static int nct7904_write_temp(struct device *dev, u32 attr, int channel,
			      long val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret;
	unsigned int reg1, reg2, reg3;

	val = clamp_val(val / 1000, -128, 127);

	switch (attr) {
	case hwmon_temp_max:
		reg1 = LTD_HV_LL_REG;
		reg2 = TEMP_CH1_W_REG;
		reg3 = DTS_T_CPU1_W_REG;
		break;
	case hwmon_temp_max_hyst:
		reg1 = LTD_LV_LL_REG;
		reg2 = TEMP_CH1_WH_REG;
		reg3 = DTS_T_CPU1_WH_REG;
		break;
	case hwmon_temp_crit:
		reg1 = LTD_HV_HL_REG;
		reg2 = TEMP_CH1_C_REG;
		reg3 = DTS_T_CPU1_C_REG;
		break;
	case hwmon_temp_crit_hyst:
		reg1 = LTD_LV_HL_REG;
		reg2 = TEMP_CH1_CH_REG;
		reg3 = DTS_T_CPU1_CH_REG;
		break;
	default:
		return -EOPNOTSUPP;
	}
	if (channel == 4)
		ret = nct7904_write_reg(data, BANK_1, reg1, val);
	else if (channel < 5)
		ret = nct7904_write_reg(data, BANK_1,
					reg2 + channel * 8, val);
	else
		ret = nct7904_write_reg(data, BANK_1,
					reg3 + (channel - 5) * 4, val);

	return ret;
}

static int nct7904_write_fan(struct device *dev, u32 attr, int channel,
			     long val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret;
	u8 tmp;

	switch (attr) {
	case hwmon_fan_min:
		if (val <= 0)
			return -EINVAL;

		val = clamp_val(DIV_ROUND_CLOSEST(1350000, val), 1, 0x1fff);
		tmp = (val >> 5) & 0xff;
		ret = nct7904_write_reg(data, BANK_1,
					FANIN1_HV_HL_REG + channel * 2, tmp);
		if (ret < 0)
			return ret;
		tmp = val & 0x1f;
		ret = nct7904_write_reg(data, BANK_1,
					FANIN1_LV_HL_REG + channel * 2, tmp);
		return ret;
	default:
		return -EOPNOTSUPP;
	}
}

static int nct7904_write_in(struct device *dev, u32 attr, int channel,
			    long val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret, index, tmp;

	index = nct7904_chan_to_index[channel];

	if (index < 14)
		val = val / 2; /* 0.002V scale */
	else
		val = val / 6; /* 0.006V scale */

	val = clamp_val(val, 0, 0x7ff);

	switch (attr) {
	case hwmon_in_min:
		tmp = nct7904_read_reg(data, BANK_1,
				       VSEN1_LV_LL_REG + index * 4);
		if (tmp < 0)
			return tmp;
		tmp &= ~0x7;
		tmp |= val & 0x7;
		ret = nct7904_write_reg(data, BANK_1,
					VSEN1_LV_LL_REG + index * 4, tmp);
		if (ret < 0)
			return ret;
		tmp = nct7904_read_reg(data, BANK_1,
				       VSEN1_HV_LL_REG + index * 4);
		if (tmp < 0)
			return tmp;
		tmp = (val >> 3) & 0xff;
		ret = nct7904_write_reg(data, BANK_1,
					VSEN1_HV_LL_REG + index * 4, tmp);
		return ret;
	case hwmon_in_max:
		tmp = nct7904_read_reg(data, BANK_1,
				       VSEN1_LV_HL_REG + index * 4);
		if (tmp < 0)
			return tmp;
		tmp &= ~0x7;
		tmp |= val & 0x7;
		ret = nct7904_write_reg(data, BANK_1,
					VSEN1_LV_HL_REG + index * 4, tmp);
		if (ret < 0)
			return ret;
		tmp = nct7904_read_reg(data, BANK_1,
				       VSEN1_HV_HL_REG + index * 4);
		if (tmp < 0)
			return tmp;
		tmp = (val >> 3) & 0xff;
		ret = nct7904_write_reg(data, BANK_1,
					VSEN1_HV_HL_REG + index * 4, tmp);
		return ret;
	default:
		return -EOPNOTSUPP;
	}
}

static int nct7904_write_pwm(struct device *dev, u32 attr, int channel,
			     long val)
{
	struct nct7904_data *data = dev_get_drvdata(dev);
	int ret;

	switch (attr) {
	case hwmon_pwm_input:
		if (val < 0 || val > 255)
			return -EINVAL;
		ret = nct7904_write_reg(data, BANK_3, FANCTL1_OUT_REG + channel,
					val);
		return ret;
	case hwmon_pwm_enable:
		if (val < 1 || val > 2 ||
		    (val == 2 && !data->fan_mode[channel]))
			return -EINVAL;
		ret = nct7904_write_reg(data, BANK_3, FANCTL1_FMR_REG + channel,
					val == 2 ? data->fan_mode[channel] : 0);
		return ret;
	default:
		return -EOPNOTSUPP;
	}
}

static umode_t nct7904_pwm_is_visible(const void *_data, u32 attr, int channel)
{
	switch (attr) {
	case hwmon_pwm_input:
	case hwmon_pwm_enable:
		return 0644;
	default:
		return 0;
	}
}

static int nct7904_read(struct device *dev, enum hwmon_sensor_types type,
			u32 attr, int channel, long *val)
{
	switch (type) {
	case hwmon_in:
		return nct7904_read_in(dev, attr, channel, val);
	case hwmon_fan:
		return nct7904_read_fan(dev, attr, channel, val);
	case hwmon_pwm:
		return nct7904_read_pwm(dev, attr, channel, val);
	case hwmon_temp:
		return nct7904_read_temp(dev, attr, channel, val);
	default:
		return -EOPNOTSUPP;
	}
}

static int nct7904_write(struct device *dev, enum hwmon_sensor_types type,
			 u32 attr, int channel, long val)
{
	switch (type) {
	case hwmon_in:
		return nct7904_write_in(dev, attr, channel, val);
	case hwmon_fan:
		return nct7904_write_fan(dev, attr, channel, val);
	case hwmon_pwm:
		return nct7904_write_pwm(dev, attr, channel, val);
	case hwmon_temp:
		return nct7904_write_temp(dev, attr, channel, val);
	default:
		return -EOPNOTSUPP;
	}
}

static umode_t nct7904_is_visible(const void *data,
				  enum hwmon_sensor_types type,
				  u32 attr, int channel)
{
	switch (type) {
	case hwmon_in:
		return nct7904_in_is_visible(data, attr, channel);
	case hwmon_fan:
		return nct7904_fan_is_visible(data, attr, channel);
	case hwmon_pwm:
		return nct7904_pwm_is_visible(data, attr, channel);
	case hwmon_temp:
		return nct7904_temp_is_visible(data, attr, channel);
	default:
		return 0;
	}
}

/* Return 0 if detection is successful, -ENODEV otherwise */
static int nct7904_detect(struct i2c_client *client,
			  struct i2c_board_info *info)
{
	struct i2c_adapter *adapter = client->adapter;

	if (!i2c_check_functionality(adapter,
				     I2C_FUNC_SMBUS_READ_BYTE |
				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
		return -ENODEV;

	/* Determine the chip type. */
	if (i2c_smbus_read_byte_data(client, VENDOR_ID_REG) != NUVOTON_ID ||
	    i2c_smbus_read_byte_data(client, CHIP_ID_REG) != NCT7904_ID ||
	    (i2c_smbus_read_byte_data(client, DEVICE_ID_REG) & 0xf0) != 0x50 ||
	    (i2c_smbus_read_byte_data(client, BANK_SEL_REG) & 0xf8) != 0x00)
		return -ENODEV;

	strlcpy(info->type, "nct7904", I2C_NAME_SIZE);

	return 0;
}

static const struct hwmon_channel_info *nct7904_info[] = {
	HWMON_CHANNEL_INFO(in,
			   /* dummy, skipped in is_visible */
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM,
			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
			   HWMON_I_ALARM),
	HWMON_CHANNEL_INFO(fan,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM),
	HWMON_CHANNEL_INFO(pwm,
			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
	HWMON_CHANNEL_INFO(temp,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST,
			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
			   HWMON_T_CRIT_HYST),
	NULL
};

static const struct hwmon_ops nct7904_hwmon_ops = {
	.is_visible = nct7904_is_visible,
	.read = nct7904_read,
	.write = nct7904_write,
};

static const struct hwmon_chip_info nct7904_chip_info = {
	.ops = &nct7904_hwmon_ops,
	.info = nct7904_info,
};

static int nct7904_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct nct7904_data *data;
	struct device *hwmon_dev;
	struct device *dev = &client->dev;
	int ret, i;
	u32 mask;
	u8 val, bit;

	data = devm_kzalloc(dev, sizeof(struct nct7904_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->client = client;
	mutex_init(&data->bank_lock);
	data->bank_sel = -1;

	/* Setup sensor groups. */
	/* FANIN attributes */
	ret = nct7904_read_reg16(data, BANK_0, FANIN_CTRL0_REG);
	if (ret < 0)
		return ret;
	data->fanin_mask = (ret >> 8) | ((ret & 0xff) << 8);

	/*
	 * VSEN attributes
	 *
	 * Note: voltage sensors overlap with external temperature
	 * sensors. So, if we ever decide to support the latter
	 * we will have to adjust 'vsen_mask' accordingly.
	 */
	mask = 0;
	ret = nct7904_read_reg16(data, BANK_0, VT_ADC_CTRL0_REG);
	if (ret >= 0)
		mask = (ret >> 8) | ((ret & 0xff) << 8);
	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
	if (ret >= 0)
		mask |= (ret << 16);
	data->vsen_mask = mask;

	/* CPU_TEMP attributes */
	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL0_REG);
	if (ret < 0)
		return ret;

	if ((ret & 0x6) == 0x6)
		data->tcpu_mask |= 1; /* TR1 */
	if ((ret & 0x18) == 0x18)
		data->tcpu_mask |= 2; /* TR2 */
	if ((ret & 0x20) == 0x20)
		data->tcpu_mask |= 4; /* TR3 */
	if ((ret & 0x80) == 0x80)
		data->tcpu_mask |= 8; /* TR4 */

	/* LTD */
	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
	if (ret < 0)
		return ret;
	if ((ret & 0x02) == 0x02)
		data->tcpu_mask |= 0x10;

	/* Multi-Function detecting for Volt and TR/TD */
	ret = nct7904_read_reg(data, BANK_0, VT_ADC_MD_REG);
	if (ret < 0)
		return ret;

	data->temp_mode = 0;
	for (i = 0; i < 4; i++) {
		val = (ret >> (i * 2)) & 0x03;
		bit = (1 << i);
		if (val == VOLT_MONITOR_MODE) {
			data->tcpu_mask &= ~bit;
		} else if (val == THERMAL_DIODE_MODE && i < 2) {
			data->temp_mode |= bit;
			data->vsen_mask &= ~(0x06 << (i * 2));
		} else if (val == THERMISTOR_MODE) {
			data->vsen_mask &= ~(0x02 << (i * 2));
		} else {
			/* Reserved */
			data->tcpu_mask &= ~bit;
			data->vsen_mask &= ~(0x06 << (i * 2));
		}
	}

	/* PECI */
	ret = nct7904_read_reg(data, BANK_2, PFE_REG);
	if (ret < 0)
		return ret;
	if (ret & 0x80) {
		data->enable_dts = 1; /* Enable DTS & PECI */
	} else {
		ret = nct7904_read_reg(data, BANK_2, TSI_CTRL_REG);
		if (ret < 0)
			return ret;
		if (ret & 0x80)
			data->enable_dts = 0x3; /* Enable DTS & TSI */
	}

	/* Check DTS enable status */
	if (data->enable_dts) {
		ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG);
		if (ret < 0)
			return ret;
		data->has_dts = ret & 0xF;
		if (data->enable_dts & ENABLE_TSI) {
			ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG);
			if (ret < 0)
				return ret;
			data->has_dts |= (ret & 0xF) << 4;
		}
	}

	for (i = 0; i < FANCTL_MAX; i++) {
		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + i);
		if (ret < 0)
			return ret;
		data->fan_mode[i] = ret;
	}

	hwmon_dev =
		devm_hwmon_device_register_with_info(dev, client->name, data,
						     &nct7904_chip_info, NULL);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct i2c_device_id nct7904_id[] = {
	{"nct7904", 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, nct7904_id);

static struct i2c_driver nct7904_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		.name = "nct7904",
	},
	.probe = nct7904_probe,
	.id_table = nct7904_id,
	.detect = nct7904_detect,
	.address_list = normal_i2c,
};

module_i2c_driver(nct7904_driver);

MODULE_AUTHOR("Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>");
MODULE_DESCRIPTION("Hwmon driver for NUVOTON NCT7904");
MODULE_LICENSE("GPL");