aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/power/ab8500_btemp.c
blob: 7f9a4547dccd9bf757fa1197e5a26ae0a319de1f (plain) (blame)
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
/*
 * Copyright (C) ST-Ericsson SA 2012
 *
 * Battery temperature driver for AB8500
 *
 * License Terms: GNU General Public License v2
 * Author:
 *	Johan Palsson <johan.palsson@stericsson.com>
 *	Karl Komierowski <karl.komierowski@stericsson.com>
 *	Arun R Murthy <arun.murthy@stericsson.com>
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/completion.h>
#include <linux/workqueue.h>
#include <linux/jiffies.h>
#include <linux/of.h>
#include <linux/mfd/core.h>
#include <linux/mfd/abx500.h>
#include <linux/mfd/abx500/ab8500.h>
#include <linux/mfd/abx500/ab8500-bm.h>
#include <linux/mfd/abx500/ab8500-gpadc.h>

#define VTVOUT_V			1800

#define BTEMP_THERMAL_LOW_LIMIT		-10
#define BTEMP_THERMAL_MED_LIMIT		0
#define BTEMP_THERMAL_HIGH_LIMIT_52	52
#define BTEMP_THERMAL_HIGH_LIMIT_57	57
#define BTEMP_THERMAL_HIGH_LIMIT_62	62

#define BTEMP_BATCTRL_CURR_SRC_7UA	7
#define BTEMP_BATCTRL_CURR_SRC_20UA	20

#define BTEMP_BATCTRL_CURR_SRC_16UA	16
#define BTEMP_BATCTRL_CURR_SRC_18UA	18

#define BTEMP_BATCTRL_CURR_SRC_60UA	60
#define BTEMP_BATCTRL_CURR_SRC_120UA	120

#define to_ab8500_btemp_device_info(x) container_of((x), \
	struct ab8500_btemp, btemp_psy);

/**
 * struct ab8500_btemp_interrupts - ab8500 interrupts
 * @name:	name of the interrupt
 * @isr		function pointer to the isr
 */
struct ab8500_btemp_interrupts {
	char *name;
	irqreturn_t (*isr)(int irq, void *data);
};

struct ab8500_btemp_events {
	bool batt_rem;
	bool btemp_high;
	bool btemp_medhigh;
	bool btemp_lowmed;
	bool btemp_low;
	bool ac_conn;
	bool usb_conn;
};

struct ab8500_btemp_ranges {
	int btemp_high_limit;
	int btemp_med_limit;
	int btemp_low_limit;
};

/**
 * struct ab8500_btemp - ab8500 BTEMP device information
 * @dev:		Pointer to the structure device
 * @node:		List of AB8500 BTEMPs, hence prepared for reentrance
 * @curr_source:	What current source we use, in uA
 * @bat_temp:		Dispatched battery temperature in degree Celcius
 * @prev_bat_temp	Last measured battery temperature in degree Celcius
 * @parent:		Pointer to the struct ab8500
 * @gpadc:		Pointer to the struct gpadc
 * @fg:			Pointer to the struct fg
 * @bm:           	Platform specific battery management information
 * @btemp_psy:		Structure for BTEMP specific battery properties
 * @events:		Structure for information about events triggered
 * @btemp_ranges:	Battery temperature range structure
 * @btemp_wq:		Work queue for measuring the temperature periodically
 * @btemp_periodic_work:	Work for measuring the temperature periodically
 * @initialized:	True if battery id read.
 */
struct ab8500_btemp {
	struct device *dev;
	struct list_head node;
	int curr_source;
	int bat_temp;
	int prev_bat_temp;
	struct ab8500 *parent;
	struct ab8500_gpadc *gpadc;
	struct ab8500_fg *fg;
	struct abx500_bm_data *bm;
	struct power_supply btemp_psy;
	struct ab8500_btemp_events events;
	struct ab8500_btemp_ranges btemp_ranges;
	struct workqueue_struct *btemp_wq;
	struct delayed_work btemp_periodic_work;
	bool initialized;
};

/* BTEMP power supply properties */
static enum power_supply_property ab8500_btemp_props[] = {
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_ONLINE,
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_TEMP,
};

static LIST_HEAD(ab8500_btemp_list);

/**
 * ab8500_btemp_get() - returns a reference to the primary AB8500 BTEMP
 * (i.e. the first BTEMP in the instance list)
 */
struct ab8500_btemp *ab8500_btemp_get(void)
{
	struct ab8500_btemp *btemp;
	btemp = list_first_entry(&ab8500_btemp_list, struct ab8500_btemp, node);

	return btemp;
}
EXPORT_SYMBOL(ab8500_btemp_get);

/**
 * ab8500_btemp_batctrl_volt_to_res() - convert batctrl voltage to resistance
 * @di:		pointer to the ab8500_btemp structure
 * @v_batctrl:	measured batctrl voltage
 * @inst_curr:	measured instant current
 *
 * This function returns the battery resistance that is
 * derived from the BATCTRL voltage.
 * Returns value in Ohms.
 */
static int ab8500_btemp_batctrl_volt_to_res(struct ab8500_btemp *di,
	int v_batctrl, int inst_curr)
{
	int rbs;

	if (is_ab8500_1p1_or_earlier(di->parent)) {
		/*
		 * For ABB cut1.0 and 1.1 BAT_CTRL is internally
		 * connected to 1.8V through a 450k resistor
		 */
		return (450000 * (v_batctrl)) / (1800 - v_batctrl);
	}

	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL) {
		/*
		 * If the battery has internal NTC, we use the current
		 * source to calculate the resistance.
		 */
		rbs = (v_batctrl * 1000
		       - di->bm->gnd_lift_resistance * inst_curr)
		      / di->curr_source;
	} else {
		/*
		 * BAT_CTRL is internally
		 * connected to 1.8V through a 80k resistor
		 */
		rbs = (80000 * (v_batctrl)) / (1800 - v_batctrl);
	}

	return rbs;
}

/**
 * ab8500_btemp_read_batctrl_voltage() - measure batctrl voltage
 * @di:		pointer to the ab8500_btemp structure
 *
 * This function returns the voltage on BATCTRL. Returns value in mV.
 */
static int ab8500_btemp_read_batctrl_voltage(struct ab8500_btemp *di)
{
	int vbtemp;
	static int prev;

	vbtemp = ab8500_gpadc_convert(di->gpadc, BAT_CTRL);
	if (vbtemp < 0) {
		dev_err(di->dev,
			"%s gpadc conversion failed, using previous value",
			__func__);
		return prev;
	}
	prev = vbtemp;
	return vbtemp;
}

/**
 * ab8500_btemp_curr_source_enable() - enable/disable batctrl current source
 * @di:		pointer to the ab8500_btemp structure
 * @enable:	enable or disable the current source
 *
 * Enable or disable the current sources for the BatCtrl AD channel
 */
static int ab8500_btemp_curr_source_enable(struct ab8500_btemp *di,
	bool enable)
{
	int curr;
	int ret = 0;

	/*
	 * BATCTRL current sources are included on AB8500 cut2.0
	 * and future versions
	 */
	if (is_ab8500_1p1_or_earlier(di->parent))
		return 0;

	/* Only do this for batteries with internal NTC */
	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && enable) {

		if (is_ab8540(di->parent)) {
			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_60UA)
				curr = BAT_CTRL_60U_ENA;
			else
				curr = BAT_CTRL_120U_ENA;
		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_16UA)
				curr = BAT_CTRL_16U_ENA;
			else
				curr = BAT_CTRL_18U_ENA;
		} else {
			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_7UA)
				curr = BAT_CTRL_7U_ENA;
			else
				curr = BAT_CTRL_20U_ENA;
		}

		dev_dbg(di->dev, "Set BATCTRL %duA\n", di->curr_source);

		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			FORCE_BAT_CTRL_CMP_HIGH, FORCE_BAT_CTRL_CMP_HIGH);
		if (ret) {
			dev_err(di->dev, "%s failed setting cmp_force\n",
				__func__);
			return ret;
		}

		/*
		 * We have to wait one 32kHz cycle before enabling
		 * the current source, since ForceBatCtrlCmpHigh needs
		 * to be written in a separate cycle
		 */
		udelay(32);

		ret = abx500_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			FORCE_BAT_CTRL_CMP_HIGH | curr);
		if (ret) {
			dev_err(di->dev, "%s failed enabling current source\n",
				__func__);
			goto disable_curr_source;
		}
	} else if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && !enable) {
		dev_dbg(di->dev, "Disable BATCTRL curr source\n");

		if (is_ab8540(di->parent)) {
			/* Write 0 to the curr bits */
			ret = abx500_mask_and_set_register_interruptible(
				di->dev,
				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
				BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA,
				~(BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA));
		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
			/* Write 0 to the curr bits */
			ret = abx500_mask_and_set_register_interruptible(
				di->dev,
				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
				BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA,
				~(BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA));
		} else {
			/* Write 0 to the curr bits */
			ret = abx500_mask_and_set_register_interruptible(
				di->dev,
				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
				BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
				~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
		}

		if (ret) {
			dev_err(di->dev, "%s failed disabling current source\n",
				__func__);
			goto disable_curr_source;
		}

		/* Enable Pull-Up and comparator */
		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
		if (ret) {
			dev_err(di->dev, "%s failed enabling PU and comp\n",
				__func__);
			goto enable_pu_comp;
		}

		/*
		 * We have to wait one 32kHz cycle before disabling
		 * ForceBatCtrlCmpHigh since this needs to be written
		 * in a separate cycle
		 */
		udelay(32);

		/* Disable 'force comparator' */
		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
		if (ret) {
			dev_err(di->dev, "%s failed disabling force comp\n",
				__func__);
			goto disable_force_comp;
		}
	}
	return ret;

	/*
	 * We have to try unsetting FORCE_BAT_CTRL_CMP_HIGH one more time
	 * if we got an error above
	 */
disable_curr_source:
	if (is_ab8540(di->parent)) {
		/* Write 0 to the curr bits */
		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA,
			~(BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA));
	} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
		/* Write 0 to the curr bits */
		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA,
			~(BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA));
	} else {
		/* Write 0 to the curr bits */
		ret = abx500_mask_and_set_register_interruptible(di->dev,
			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
			BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
			~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
	}

	if (ret) {
		dev_err(di->dev, "%s failed disabling current source\n",
			__func__);
		return ret;
	}
enable_pu_comp:
	/* Enable Pull-Up and comparator */
	ret = abx500_mask_and_set_register_interruptible(di->dev,
		AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
	if (ret) {
		dev_err(di->dev, "%s failed enabling PU and comp\n",
			__func__);
		return ret;
	}

disable_force_comp:
	/*
	 * We have to wait one 32kHz cycle before disabling
	 * ForceBatCtrlCmpHigh since this needs to be written
	 * in a separate cycle
	 */
	udelay(32);

	/* Disable 'force comparator' */
	ret = abx500_mask_and_set_register_interruptible(di->dev,
		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
		FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
	if (ret) {
		dev_err(di->dev, "%s failed disabling force comp\n",
			__func__);
		return ret;
	}

	return ret;
}

/**
 * ab8500_btemp_get_batctrl_res() - get battery resistance
 * @di:		pointer to the ab8500_btemp structure
 *
 * This function returns the battery pack identification resistance.
 * Returns value in Ohms.
 */
static int ab8500_btemp_get_batctrl_res(struct ab8500_btemp *di)
{
	int ret;
	int batctrl = 0;
	int res;
	int inst_curr;
	int i;

	/*
	 * BATCTRL current sources are included on AB8500 cut2.0
	 * and future versions
	 */
	ret = ab8500_btemp_curr_source_enable(di, true);
	if (ret) {
		dev_err(di->dev, "%s curr source enabled failed\n", __func__);
		return ret;
	}

	if (!di->fg)
		di->fg = ab8500_fg_get();
	if (!di->fg) {
		dev_err(di->dev, "No fg found\n");
		return -EINVAL;
	}

	ret = ab8500_fg_inst_curr_start(di->fg);

	if (ret) {
		dev_err(di->dev, "Failed to start current measurement\n");
		return ret;
	}

	do {
		msleep(20);
	} while (!ab8500_fg_inst_curr_started(di->fg));

	i = 0;

	do {
		batctrl += ab8500_btemp_read_batctrl_voltage(di);
		i++;
		msleep(20);
	} while (!ab8500_fg_inst_curr_done(di->fg));
	batctrl /= i;

	ret = ab8500_fg_inst_curr_finalize(di->fg, &inst_curr);
	if (ret) {
		dev_err(di->dev, "Failed to finalize current measurement\n");
		return ret;
	}

	res = ab8500_btemp_batctrl_volt_to_res(di, batctrl, inst_curr);

	ret = ab8500_btemp_curr_source_enable(di, false);
	if (ret) {
		dev_err(di->dev, "%s curr source disable failed\n", __func__);
		return ret;
	}

	dev_dbg(di->dev, "%s batctrl: %d res: %d inst_curr: %d samples: %d\n",
		__func__, batctrl, res, inst_curr, i);

	return res;
}

/**
 * ab8500_btemp_res_to_temp() - resistance to temperature
 * @di:		pointer to the ab8500_btemp structure
 * @tbl:	pointer to the resiatance to temperature table
 * @tbl_size:	size of the resistance to temperature table
 * @res:	resistance to calculate the temperature from
 *
 * This function returns the battery temperature in degrees Celcius
 * based on the NTC resistance.
 */
static int ab8500_btemp_res_to_temp(struct ab8500_btemp *di,
	const struct abx500_res_to_temp *tbl, int tbl_size, int res)
{
	int i, temp;
	/*
	 * Calculate the formula for the straight line
	 * Simple interpolation if we are within
	 * the resistance table limits, extrapolate
	 * if resistance is outside the limits.
	 */
	if (res > tbl[0].resist)
		i = 0;
	else if (res <= tbl[tbl_size - 1].resist)
		i = tbl_size - 2;
	else {
		i = 0;
		while (!(res <= tbl[i].resist &&
			res > tbl[i + 1].resist))
			i++;
	}

	temp = tbl[i].temp + ((tbl[i + 1].temp - tbl[i].temp) *
		(res - tbl[i].resist)) / (tbl[i + 1].resist - tbl[i].resist);
	return temp;
}

/**
 * ab8500_btemp_measure_temp() - measure battery temperature
 * @di:		pointer to the ab8500_btemp structure
 *
 * Returns battery temperature (on success) else the previous temperature
 */
static int ab8500_btemp_measure_temp(struct ab8500_btemp *di)
{
	int temp;
	static int prev;
	int rbat, rntc, vntc;
	u8 id;

	id = di->bm->batt_id;

	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
			id != BATTERY_UNKNOWN) {

		rbat = ab8500_btemp_get_batctrl_res(di);
		if (rbat < 0) {
			dev_err(di->dev, "%s get batctrl res failed\n",
				__func__);
			/*
			 * Return out-of-range temperature so that
			 * charging is stopped
			 */
			return BTEMP_THERMAL_LOW_LIMIT;
		}

		temp = ab8500_btemp_res_to_temp(di,
			di->bm->bat_type[id].r_to_t_tbl,
			di->bm->bat_type[id].n_temp_tbl_elements, rbat);
	} else {
		vntc = ab8500_gpadc_convert(di->gpadc, BTEMP_BALL);
		if (vntc < 0) {
			dev_err(di->dev,
				"%s gpadc conversion failed,"
				" using previous value\n", __func__);
			return prev;
		}
		/*
		 * The PCB NTC is sourced from VTVOUT via a 230kOhm
		 * resistor.
		 */
		rntc = 230000 * vntc / (VTVOUT_V - vntc);

		temp = ab8500_btemp_res_to_temp(di,
			di->bm->bat_type[id].r_to_t_tbl,
			di->bm->bat_type[id].n_temp_tbl_elements, rntc);
		prev = temp;
	}
	dev_dbg(di->dev, "Battery temperature is %d\n", temp);
	return temp;
}

/**
 * ab8500_btemp_id() - Identify the connected battery
 * @di:		pointer to the ab8500_btemp structure
 *
 * This function will try to identify the battery by reading the ID
 * resistor. Some brands use a combined ID resistor with a NTC resistor to
 * both be able to identify and to read the temperature of it.
 */
static int ab8500_btemp_id(struct ab8500_btemp *di)
{
	int res;
	u8 i;
	if (is_ab8540(di->parent))
		di->curr_source = BTEMP_BATCTRL_CURR_SRC_60UA;
	else if (is_ab9540(di->parent) || is_ab8505(di->parent))
		di->curr_source = BTEMP_BATCTRL_CURR_SRC_16UA;
	else
		di->curr_source = BTEMP_BATCTRL_CURR_SRC_7UA;

	di->bm->batt_id = BATTERY_UNKNOWN;

	res =  ab8500_btemp_get_batctrl_res(di);
	if (res < 0) {
		dev_err(di->dev, "%s get batctrl res failed\n", __func__);
		return -ENXIO;
	}

	/* BATTERY_UNKNOWN is defined on position 0, skip it! */
	for (i = BATTERY_UNKNOWN + 1; i < di->bm->n_btypes; i++) {
		if ((res <= di->bm->bat_type[i].resis_high) &&
			(res >= di->bm->bat_type[i].resis_low)) {
			dev_dbg(di->dev, "Battery detected on %s"
				" low %d < res %d < high: %d"
				" index: %d\n",
				di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL ?
				"BATCTRL" : "BATTEMP",
				di->bm->bat_type[i].resis_low, res,
				di->bm->bat_type[i].resis_high, i);

			di->bm->batt_id = i;
			break;
		}
	}

	if (di->bm->batt_id == BATTERY_UNKNOWN) {
		dev_warn(di->dev, "Battery identified as unknown"
			", resistance %d Ohm\n", res);
		return -ENXIO;
	}

	/*
	 * We only have to change current source if the
	 * detected type is Type 1.
	 */
	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
	    di->bm->batt_id == 1) {
		if (is_ab8540(di->parent)) {
			dev_dbg(di->dev,
				"Set BATCTRL current source to 60uA\n");
			di->curr_source = BTEMP_BATCTRL_CURR_SRC_60UA;
		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
			dev_dbg(di->dev,
				"Set BATCTRL current source to 16uA\n");
			di->curr_source = BTEMP_BATCTRL_CURR_SRC_16UA;
		} else {
			dev_dbg(di->dev, "Set BATCTRL current source to 20uA\n");
			di->curr_source = BTEMP_BATCTRL_CURR_SRC_20UA;
		}
	}

	return di->bm->batt_id;
}

/**
 * ab8500_btemp_periodic_work() - Measuring the temperature periodically
 * @work:	pointer to the work_struct structure
 *
 * Work function for measuring the temperature periodically
 */
static void ab8500_btemp_periodic_work(struct work_struct *work)
{
	int interval;
	int bat_temp;
	struct ab8500_btemp *di = container_of(work,
		struct ab8500_btemp, btemp_periodic_work.work);

	if (!di->initialized) {
		/* Identify the battery */
		if (ab8500_btemp_id(di) < 0)
			dev_warn(di->dev, "failed to identify the battery\n");
	}

	bat_temp = ab8500_btemp_measure_temp(di);
	/*
	 * Filter battery temperature.
	 * Allow direct updates on temperature only if two samples result in
	 * same temperature. Else only allow 1 degree change from previous
	 * reported value in the direction of the new measurement.
	 */
	if ((bat_temp == di->prev_bat_temp) || !di->initialized) {
		if ((di->bat_temp != di->prev_bat_temp) || !di->initialized) {
			di->initialized = true;
			di->bat_temp = bat_temp;
			power_supply_changed(&di->btemp_psy);
		}
	} else if (bat_temp < di->prev_bat_temp) {
		di->bat_temp--;
		power_supply_changed(&di->btemp_psy);
	} else if (bat_temp > di->prev_bat_temp) {
		di->bat_temp++;
		power_supply_changed(&di->btemp_psy);
	}
	di->prev_bat_temp = bat_temp;

	if (di->events.ac_conn || di->events.usb_conn)
		interval = di->bm->temp_interval_chg;
	else
		interval = di->bm->temp_interval_nochg;

	/* Schedule a new measurement */
	queue_delayed_work(di->btemp_wq,
		&di->btemp_periodic_work,
		round_jiffies(interval * HZ));
}

/**
 * ab8500_btemp_batctrlindb_handler() - battery removal detected
 * @irq:       interrupt number
 * @_di:       void pointer that has to address of ab8500_btemp
 *
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_btemp_batctrlindb_handler(int irq, void *_di)
{
	struct ab8500_btemp *di = _di;
	dev_err(di->dev, "Battery removal detected!\n");

	di->events.batt_rem = true;
	power_supply_changed(&di->btemp_psy);

	return IRQ_HANDLED;
}

/**
 * ab8500_btemp_templow_handler() - battery temp lower than 10 degrees
 * @irq:       interrupt number
 * @_di:       void pointer that has to address of ab8500_btemp
 *
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_btemp_templow_handler(int irq, void *_di)
{
	struct ab8500_btemp *di = _di;

	if (is_ab8500_3p3_or_earlier(di->parent)) {
		dev_dbg(di->dev, "Ignore false btemp low irq"
			" for ABB cut 1.0, 1.1, 2.0 and 3.3\n");
	} else {
		dev_crit(di->dev, "Battery temperature lower than -10deg c\n");

		di->events.btemp_low = true;
		di->events.btemp_high = false;
		di->events.btemp_medhigh = false;
		di->events.btemp_lowmed = false;
		power_supply_changed(&di->btemp_psy);
	}

	return IRQ_HANDLED;
}

/**
 * ab8500_btemp_temphigh_handler() - battery temp higher than max temp
 * @irq:       interrupt number
 * @_di:       void pointer that has to address of ab8500_btemp
 *
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_btemp_temphigh_handler(int irq, void *_di)
{
	struct ab8500_btemp *di = _di;

	dev_crit(di->dev, "Battery temperature is higher than MAX temp\n");

	di->events.btemp_high = true;
	di->events.btemp_medhigh = false;
	di->events.btemp_lowmed = false;
	di->events.btemp_low = false;
	power_supply_changed(&di->btemp_psy);

	return IRQ_HANDLED;
}

/**
 * ab8500_btemp_lowmed_handler() - battery temp between low and medium
 * @irq:       interrupt number
 * @_di:       void pointer that has to address of ab8500_btemp
 *
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_btemp_lowmed_handler(int irq, void *_di)
{
	struct ab8500_btemp *di = _di;

	dev_dbg(di->dev, "Battery temperature is between low and medium\n");

	di->events.btemp_lowmed = true;
	di->events.btemp_medhigh = false;
	di->events.btemp_high = false;
	di->events.btemp_low = false;
	power_supply_changed(&di->btemp_psy);

	return IRQ_HANDLED;
}

/**
 * ab8500_btemp_medhigh_handler() - battery temp between medium and high
 * @irq:       interrupt number
 * @_di:       void pointer that has to address of ab8500_btemp
 *
 * Returns IRQ status(IRQ_HANDLED)
 */
static irqreturn_t ab8500_btemp_medhigh_handler(int irq, void *_di)
{
	struct ab8500_btemp *di = _di;

	dev_dbg(di->dev, "Battery temperature is between medium and high\n");

	di->events.btemp_medhigh = true;
	di->events.btemp_lowmed = false;
	di->events.btemp_high = false;
	di->events.btemp_low = false;
	power_supply_changed(&di->btemp_psy);

	return IRQ_HANDLED;
}

/**
 * ab8500_btemp_periodic() - Periodic temperature measurements
 * @di:		pointer to the ab8500_btemp structure
 * @enable:	enable or disable periodic temperature measurements
 *
 * Starts of stops periodic temperature measurements. Periodic measurements
 * should only be done when a charger is connected.
 */
static void ab8500_btemp_periodic(struct ab8500_btemp *di,
	bool enable)
{
	dev_dbg(di->dev, "Enable periodic temperature measurements: %d\n",
		enable);
	/*
	 * Make sure a new measurement is done directly by cancelling
	 * any pending work
	 */
	cancel_delayed_work_sync(&di->btemp_periodic_work);

	if (enable)
		queue_delayed_work(di->btemp_wq, &di->btemp_periodic_work, 0);
}

/**
 * ab8500_btemp_get_temp() - get battery temperature
 * @di:		pointer to the ab8500_btemp structure
 *
 * Returns battery temperature
 */
int ab8500_btemp_get_temp(struct ab8500_btemp *di)
{
	int temp = 0;

	/*
	 * The BTEMP events are not reliabe on AB8500 cut3.3
	 * and prior versions
	 */
	if (is_ab8500_3p3_or_earlier(di->parent)) {
		temp = di->bat_temp * 10;
	} else {
		if (di->events.btemp_low) {
			if (temp > di->btemp_ranges.btemp_low_limit)
				temp = di->btemp_ranges.btemp_low_limit * 10;
			else
				temp = di->bat_temp * 10;
		} else if (di->events.btemp_high) {
			if (temp < di->btemp_ranges.btemp_high_limit)
				temp = di->btemp_ranges.btemp_high_limit * 10;
			else
				temp = di->bat_temp * 10;
		} else if (di->events.btemp_lowmed) {
			if (temp > di->btemp_ranges.btemp_med_limit)
				temp = di->btemp_ranges.btemp_med_limit * 10;
			else
				temp = di->bat_temp * 10;
		} else if (di->events.btemp_medhigh) {
			if (temp < di->btemp_ranges.btemp_med_limit)
				temp = di->btemp_ranges.btemp_med_limit * 10;
			else
				temp = di->bat_temp * 10;
		} else
			temp = di->bat_temp * 10;
	}
	return temp;
}
EXPORT_SYMBOL(ab8500_btemp_get_temp);

/**
 * ab8500_btemp_get_batctrl_temp() - get the temperature
 * @btemp:      pointer to the btemp structure
 *
 * Returns the batctrl temperature in millidegrees
 */
int ab8500_btemp_get_batctrl_temp(struct ab8500_btemp *btemp)
{
	return btemp->bat_temp * 1000;
}
EXPORT_SYMBOL(ab8500_btemp_get_batctrl_temp);

/**
 * ab8500_btemp_get_property() - get the btemp properties
 * @psy:        pointer to the power_supply structure
 * @psp:        pointer to the power_supply_property structure
 * @val:        pointer to the power_supply_propval union
 *
 * This function gets called when an application tries to get the btemp
 * properties by reading the sysfs files.
 * online:	presence of the battery
 * present:	presence of the battery
 * technology:	battery technology
 * temp:	battery temperature
 * Returns error code in case of failure else 0(on success)
 */
static int ab8500_btemp_get_property(struct power_supply *psy,
	enum power_supply_property psp,
	union power_supply_propval *val)
{
	struct ab8500_btemp *di;

	di = to_ab8500_btemp_device_info(psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_PRESENT:
	case POWER_SUPPLY_PROP_ONLINE:
		if (di->events.batt_rem)
			val->intval = 0;
		else
			val->intval = 1;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = di->bm->bat_type[di->bm->batt_id].name;
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = ab8500_btemp_get_temp(di);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static int ab8500_btemp_get_ext_psy_data(struct device *dev, void *data)
{
	struct power_supply *psy;
	struct power_supply *ext;
	struct ab8500_btemp *di;
	union power_supply_propval ret;
	int i, j;
	bool psy_found = false;

	psy = (struct power_supply *)data;
	ext = dev_get_drvdata(dev);
	di = to_ab8500_btemp_device_info(psy);

	/*
	 * For all psy where the name of your driver
	 * appears in any supplied_to
	 */
	for (i = 0; i < ext->num_supplicants; i++) {
		if (!strcmp(ext->supplied_to[i], psy->name))
			psy_found = true;
	}

	if (!psy_found)
		return 0;

	/* Go through all properties for the psy */
	for (j = 0; j < ext->num_properties; j++) {
		enum power_supply_property prop;
		prop = ext->properties[j];

		if (ext->get_property(ext, prop, &ret))
			continue;

		switch (prop) {
		case POWER_SUPPLY_PROP_PRESENT:
			switch (ext->type) {
			case POWER_SUPPLY_TYPE_MAINS:
				/* AC disconnected */
				if (!ret.intval && di->events.ac_conn) {
					di->events.ac_conn = false;
				}
				/* AC connected */
				else if (ret.intval && !di->events.ac_conn) {
					di->events.ac_conn = true;
					if (!di->events.usb_conn)
						ab8500_btemp_periodic(di, true);
				}
				break;
			case POWER_SUPPLY_TYPE_USB:
				/* USB disconnected */
				if (!ret.intval && di->events.usb_conn) {
					di->events.usb_conn = false;
				}
				/* USB connected */
				else if (ret.intval && !di->events.usb_conn) {
					di->events.usb_conn = true;
					if (!di->events.ac_conn)
						ab8500_btemp_periodic(di, true);
				}
				break;
			default:
				break;
			}
			break;
		default:
			break;
		}
	}
	return 0;
}

/**
 * ab8500_btemp_external_power_changed() - callback for power supply changes
 * @psy:       pointer to the structure power_supply
 *
 * This function is pointing to the function pointer external_power_changed
 * of the structure power_supply.
 * This function gets executed when there is a change in the external power
 * supply to the btemp.
 */
static void ab8500_btemp_external_power_changed(struct power_supply *psy)
{
	struct ab8500_btemp *di = to_ab8500_btemp_device_info(psy);

	class_for_each_device(power_supply_class, NULL,
		&di->btemp_psy, ab8500_btemp_get_ext_psy_data);
}

/* ab8500 btemp driver interrupts and their respective isr */
static struct ab8500_btemp_interrupts ab8500_btemp_irq[] = {
	{"BAT_CTRL_INDB", ab8500_btemp_batctrlindb_handler},
	{"BTEMP_LOW", ab8500_btemp_templow_handler},
	{"BTEMP_HIGH", ab8500_btemp_temphigh_handler},
	{"BTEMP_LOW_MEDIUM", ab8500_btemp_lowmed_handler},
	{"BTEMP_MEDIUM_HIGH", ab8500_btemp_medhigh_handler},
};

#if defined(CONFIG_PM)
static int ab8500_btemp_resume(struct platform_device *pdev)
{
	struct ab8500_btemp *di = platform_get_drvdata(pdev);

	ab8500_btemp_periodic(di, true);

	return 0;
}

static int ab8500_btemp_suspend(struct platform_device *pdev,
	pm_message_t state)
{
	struct ab8500_btemp *di = platform_get_drvdata(pdev);

	ab8500_btemp_periodic(di, false);

	return 0;
}
#else
#define ab8500_btemp_suspend      NULL
#define ab8500_btemp_resume       NULL
#endif

static int ab8500_btemp_remove(struct platform_device *pdev)
{
	struct ab8500_btemp *di = platform_get_drvdata(pdev);
	int i, irq;

	/* Disable interrupts */
	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
		free_irq(irq, di);
	}

	/* Delete the work queue */
	destroy_workqueue(di->btemp_wq);

	flush_scheduled_work();
	power_supply_unregister(&di->btemp_psy);

	return 0;
}

static char *supply_interface[] = {
	"ab8500_chargalg",
	"ab8500_fg",
};

static int ab8500_btemp_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct abx500_bm_data *plat = pdev->dev.platform_data;
	struct ab8500_btemp *di;
	int irq, i, ret = 0;
	u8 val;

	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
	if (!di) {
		dev_err(&pdev->dev, "%s no mem for ab8500_btemp\n", __func__);
		return -ENOMEM;
	}

	if (!plat) {
		dev_err(&pdev->dev, "no battery management data supplied\n");
		return -EINVAL;
	}
	di->bm = plat;

	if (np) {
		ret = ab8500_bm_of_probe(&pdev->dev, np, di->bm);
		if (ret) {
			dev_err(&pdev->dev, "failed to get battery information\n");
			return ret;
		}
	}

	/* get parent data */
	di->dev = &pdev->dev;
	di->parent = dev_get_drvdata(pdev->dev.parent);
	di->gpadc = ab8500_gpadc_get("ab8500-gpadc.0");

	di->initialized = false;

	/* BTEMP supply */
	di->btemp_psy.name = "ab8500_btemp";
	di->btemp_psy.type = POWER_SUPPLY_TYPE_BATTERY;
	di->btemp_psy.properties = ab8500_btemp_props;
	di->btemp_psy.num_properties = ARRAY_SIZE(ab8500_btemp_props);
	di->btemp_psy.get_property = ab8500_btemp_get_property;
	di->btemp_psy.supplied_to = supply_interface;
	di->btemp_psy.num_supplicants = ARRAY_SIZE(supply_interface);
	di->btemp_psy.external_power_changed =
		ab8500_btemp_external_power_changed;


	/* Create a work queue for the btemp */
	di->btemp_wq =
		create_singlethread_workqueue("ab8500_btemp_wq");
	if (di->btemp_wq == NULL) {
		dev_err(di->dev, "failed to create work queue\n");
		return -ENOMEM;
	}

	/* Init work for measuring temperature periodically */
	INIT_DEFERRABLE_WORK(&di->btemp_periodic_work,
		ab8500_btemp_periodic_work);

	/* Set BTEMP thermal limits. Low and Med are fixed */
	di->btemp_ranges.btemp_low_limit = BTEMP_THERMAL_LOW_LIMIT;
	di->btemp_ranges.btemp_med_limit = BTEMP_THERMAL_MED_LIMIT;

	ret = abx500_get_register_interruptible(di->dev, AB8500_CHARGER,
		AB8500_BTEMP_HIGH_TH, &val);
	if (ret < 0) {
		dev_err(di->dev, "%s ab8500 read failed\n", __func__);
		goto free_btemp_wq;
	}
	switch (val) {
	case BTEMP_HIGH_TH_57_0:
	case BTEMP_HIGH_TH_57_1:
		di->btemp_ranges.btemp_high_limit =
			BTEMP_THERMAL_HIGH_LIMIT_57;
		break;
	case BTEMP_HIGH_TH_52:
		di->btemp_ranges.btemp_high_limit =
			BTEMP_THERMAL_HIGH_LIMIT_52;
		break;
	case BTEMP_HIGH_TH_62:
		di->btemp_ranges.btemp_high_limit =
			BTEMP_THERMAL_HIGH_LIMIT_62;
		break;
	}

	/* Register BTEMP power supply class */
	ret = power_supply_register(di->dev, &di->btemp_psy);
	if (ret) {
		dev_err(di->dev, "failed to register BTEMP psy\n");
		goto free_btemp_wq;
	}

	/* Register interrupts */
	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
		ret = request_threaded_irq(irq, NULL, ab8500_btemp_irq[i].isr,
			IRQF_SHARED | IRQF_NO_SUSPEND,
			ab8500_btemp_irq[i].name, di);

		if (ret) {
			dev_err(di->dev, "failed to request %s IRQ %d: %d\n"
				, ab8500_btemp_irq[i].name, irq, ret);
			goto free_irq;
		}
		dev_dbg(di->dev, "Requested %s IRQ %d: %d\n",
			ab8500_btemp_irq[i].name, irq, ret);
	}

	platform_set_drvdata(pdev, di);

	/* Kick off periodic temperature measurements */
	ab8500_btemp_periodic(di, true);
	list_add_tail(&di->node, &ab8500_btemp_list);

	return ret;

free_irq:
	power_supply_unregister(&di->btemp_psy);

	/* We also have to free all successfully registered irqs */
	for (i = i - 1; i >= 0; i--) {
		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
		free_irq(irq, di);
	}
free_btemp_wq:
	destroy_workqueue(di->btemp_wq);
	return ret;
}

static const struct of_device_id ab8500_btemp_match[] = {
	{ .compatible = "stericsson,ab8500-btemp", },
	{ },
};

static struct platform_driver ab8500_btemp_driver = {
	.probe = ab8500_btemp_probe,
	.remove = ab8500_btemp_remove,
	.suspend = ab8500_btemp_suspend,
	.resume = ab8500_btemp_resume,
	.driver = {
		.name = "ab8500-btemp",
		.owner = THIS_MODULE,
		.of_match_table = ab8500_btemp_match,
	},
};

static int __init ab8500_btemp_init(void)
{
	return platform_driver_register(&ab8500_btemp_driver);
}

static void __exit ab8500_btemp_exit(void)
{
	platform_driver_unregister(&ab8500_btemp_driver);
}

device_initcall(ab8500_btemp_init);
module_exit(ab8500_btemp_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Johan Palsson, Karl Komierowski, Arun R Murthy");
MODULE_ALIAS("platform:ab8500-btemp");
MODULE_DESCRIPTION("AB8500 battery temperature driver");