summaryrefslogtreecommitdiffstats
path: root/drivers/thermal/imx_thermal.c
blob: aa452acb60b6c93f2ca0d8ace93aa7c4cc883d32 (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
// SPDX-License-Identifier: GPL-2.0
//
// Copyright 2013 Freescale Semiconductor, Inc.

#include <linux/clk.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/cpu_cooling.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/thermal.h>
#include <linux/types.h>
#include <linux/nvmem-consumer.h>

#define REG_SET		0x4
#define REG_CLR		0x8
#define REG_TOG		0xc

/* i.MX6 specific */
#define IMX6_MISC0				0x0150
#define IMX6_MISC0_REFTOP_SELBIASOFF		(1 << 3)
#define IMX6_MISC1				0x0160
#define IMX6_MISC1_IRQ_TEMPHIGH			(1 << 29)
/* Below LOW and PANIC bits are only for TEMPMON_IMX6SX */
#define IMX6_MISC1_IRQ_TEMPLOW			(1 << 28)
#define IMX6_MISC1_IRQ_TEMPPANIC		(1 << 27)

#define IMX6_TEMPSENSE0				0x0180
#define IMX6_TEMPSENSE0_ALARM_VALUE_SHIFT	20
#define IMX6_TEMPSENSE0_ALARM_VALUE_MASK	(0xfff << 20)
#define IMX6_TEMPSENSE0_TEMP_CNT_SHIFT		8
#define IMX6_TEMPSENSE0_TEMP_CNT_MASK		(0xfff << 8)
#define IMX6_TEMPSENSE0_FINISHED		(1 << 2)
#define IMX6_TEMPSENSE0_MEASURE_TEMP		(1 << 1)
#define IMX6_TEMPSENSE0_POWER_DOWN		(1 << 0)

#define IMX6_TEMPSENSE1				0x0190
#define IMX6_TEMPSENSE1_MEASURE_FREQ		0xffff
#define IMX6_TEMPSENSE1_MEASURE_FREQ_SHIFT	0

#define OCOTP_MEM0			0x0480
#define OCOTP_ANA1			0x04e0

/* Below TEMPSENSE2 is only for TEMPMON_IMX6SX */
#define IMX6_TEMPSENSE2				0x0290
#define IMX6_TEMPSENSE2_LOW_VALUE_SHIFT		0
#define IMX6_TEMPSENSE2_LOW_VALUE_MASK		0xfff
#define IMX6_TEMPSENSE2_PANIC_VALUE_SHIFT	16
#define IMX6_TEMPSENSE2_PANIC_VALUE_MASK	0xfff0000

/* i.MX7 specific */
#define IMX7_ANADIG_DIGPROG			0x800
#define IMX7_TEMPSENSE0				0x300
#define IMX7_TEMPSENSE0_PANIC_ALARM_SHIFT	18
#define IMX7_TEMPSENSE0_PANIC_ALARM_MASK	(0x1ff << 18)
#define IMX7_TEMPSENSE0_HIGH_ALARM_SHIFT	9
#define IMX7_TEMPSENSE0_HIGH_ALARM_MASK		(0x1ff << 9)
#define IMX7_TEMPSENSE0_LOW_ALARM_SHIFT		0
#define IMX7_TEMPSENSE0_LOW_ALARM_MASK		0x1ff

#define IMX7_TEMPSENSE1				0x310
#define IMX7_TEMPSENSE1_MEASURE_FREQ_SHIFT	16
#define IMX7_TEMPSENSE1_MEASURE_FREQ_MASK	(0xffff << 16)
#define IMX7_TEMPSENSE1_FINISHED		(1 << 11)
#define IMX7_TEMPSENSE1_MEASURE_TEMP		(1 << 10)
#define IMX7_TEMPSENSE1_POWER_DOWN		(1 << 9)
#define IMX7_TEMPSENSE1_TEMP_VALUE_SHIFT	0
#define IMX7_TEMPSENSE1_TEMP_VALUE_MASK		0x1ff

/* The driver supports 1 passive trip point and 1 critical trip point */
enum imx_thermal_trip {
	IMX_TRIP_PASSIVE,
	IMX_TRIP_CRITICAL,
	IMX_TRIP_NUM,
};

#define IMX_POLLING_DELAY		2000 /* millisecond */
#define IMX_PASSIVE_DELAY		1000

#define TEMPMON_IMX6Q			1
#define TEMPMON_IMX6SX			2
#define TEMPMON_IMX7D			3

struct thermal_soc_data {
	u32 version;

	u32 sensor_ctrl;
	u32 power_down_mask;
	u32 measure_temp_mask;

	u32 measure_freq_ctrl;
	u32 measure_freq_mask;
	u32 measure_freq_shift;

	u32 temp_data;
	u32 temp_value_mask;
	u32 temp_value_shift;
	u32 temp_valid_mask;

	u32 panic_alarm_ctrl;
	u32 panic_alarm_mask;
	u32 panic_alarm_shift;

	u32 high_alarm_ctrl;
	u32 high_alarm_mask;
	u32 high_alarm_shift;

	u32 low_alarm_ctrl;
	u32 low_alarm_mask;
	u32 low_alarm_shift;
};

static struct thermal_soc_data thermal_imx6q_data = {
	.version = TEMPMON_IMX6Q,

	.sensor_ctrl = IMX6_TEMPSENSE0,
	.power_down_mask = IMX6_TEMPSENSE0_POWER_DOWN,
	.measure_temp_mask = IMX6_TEMPSENSE0_MEASURE_TEMP,

	.measure_freq_ctrl = IMX6_TEMPSENSE1,
	.measure_freq_shift = IMX6_TEMPSENSE1_MEASURE_FREQ_SHIFT,
	.measure_freq_mask = IMX6_TEMPSENSE1_MEASURE_FREQ,

	.temp_data = IMX6_TEMPSENSE0,
	.temp_value_mask = IMX6_TEMPSENSE0_TEMP_CNT_MASK,
	.temp_value_shift = IMX6_TEMPSENSE0_TEMP_CNT_SHIFT,
	.temp_valid_mask = IMX6_TEMPSENSE0_FINISHED,

	.high_alarm_ctrl = IMX6_TEMPSENSE0,
	.high_alarm_mask = IMX6_TEMPSENSE0_ALARM_VALUE_MASK,
	.high_alarm_shift = IMX6_TEMPSENSE0_ALARM_VALUE_SHIFT,
};

static struct thermal_soc_data thermal_imx6sx_data = {
	.version = TEMPMON_IMX6SX,

	.sensor_ctrl = IMX6_TEMPSENSE0,
	.power_down_mask = IMX6_TEMPSENSE0_POWER_DOWN,
	.measure_temp_mask = IMX6_TEMPSENSE0_MEASURE_TEMP,

	.measure_freq_ctrl = IMX6_TEMPSENSE1,
	.measure_freq_shift = IMX6_TEMPSENSE1_MEASURE_FREQ_SHIFT,
	.measure_freq_mask = IMX6_TEMPSENSE1_MEASURE_FREQ,

	.temp_data = IMX6_TEMPSENSE0,
	.temp_value_mask = IMX6_TEMPSENSE0_TEMP_CNT_MASK,
	.temp_value_shift = IMX6_TEMPSENSE0_TEMP_CNT_SHIFT,
	.temp_valid_mask = IMX6_TEMPSENSE0_FINISHED,

	.high_alarm_ctrl = IMX6_TEMPSENSE0,
	.high_alarm_mask = IMX6_TEMPSENSE0_ALARM_VALUE_MASK,
	.high_alarm_shift = IMX6_TEMPSENSE0_ALARM_VALUE_SHIFT,

	.panic_alarm_ctrl = IMX6_TEMPSENSE2,
	.panic_alarm_mask = IMX6_TEMPSENSE2_PANIC_VALUE_MASK,
	.panic_alarm_shift = IMX6_TEMPSENSE2_PANIC_VALUE_SHIFT,

	.low_alarm_ctrl = IMX6_TEMPSENSE2,
	.low_alarm_mask = IMX6_TEMPSENSE2_LOW_VALUE_MASK,
	.low_alarm_shift = IMX6_TEMPSENSE2_LOW_VALUE_SHIFT,
};

static struct thermal_soc_data thermal_imx7d_data = {
	.version = TEMPMON_IMX7D,

	.sensor_ctrl = IMX7_TEMPSENSE1,
	.power_down_mask = IMX7_TEMPSENSE1_POWER_DOWN,
	.measure_temp_mask = IMX7_TEMPSENSE1_MEASURE_TEMP,

	.measure_freq_ctrl = IMX7_TEMPSENSE1,
	.measure_freq_shift = IMX7_TEMPSENSE1_MEASURE_FREQ_SHIFT,
	.measure_freq_mask = IMX7_TEMPSENSE1_MEASURE_FREQ_MASK,

	.temp_data = IMX7_TEMPSENSE1,
	.temp_value_mask = IMX7_TEMPSENSE1_TEMP_VALUE_MASK,
	.temp_value_shift = IMX7_TEMPSENSE1_TEMP_VALUE_SHIFT,
	.temp_valid_mask = IMX7_TEMPSENSE1_FINISHED,

	.panic_alarm_ctrl = IMX7_TEMPSENSE1,
	.panic_alarm_mask = IMX7_TEMPSENSE0_PANIC_ALARM_MASK,
	.panic_alarm_shift = IMX7_TEMPSENSE0_PANIC_ALARM_SHIFT,

	.high_alarm_ctrl = IMX7_TEMPSENSE0,
	.high_alarm_mask = IMX7_TEMPSENSE0_HIGH_ALARM_MASK,
	.high_alarm_shift = IMX7_TEMPSENSE0_HIGH_ALARM_SHIFT,

	.low_alarm_ctrl = IMX7_TEMPSENSE0,
	.low_alarm_mask = IMX7_TEMPSENSE0_LOW_ALARM_MASK,
	.low_alarm_shift = IMX7_TEMPSENSE0_LOW_ALARM_SHIFT,
};

struct imx_thermal_data {
	struct cpufreq_policy *policy;
	struct thermal_zone_device *tz;
	struct thermal_cooling_device *cdev;
	enum thermal_device_mode mode;
	struct regmap *tempmon;
	u32 c1, c2; /* See formula in imx_init_calib() */
	int temp_passive;
	int temp_critical;
	int temp_max;
	int alarm_temp;
	int last_temp;
	bool irq_enabled;
	int irq;
	struct clk *thermal_clk;
	const struct thermal_soc_data *socdata;
	const char *temp_grade;
};

static void imx_set_panic_temp(struct imx_thermal_data *data,
			       int panic_temp)
{
	const struct thermal_soc_data *soc_data = data->socdata;
	struct regmap *map = data->tempmon;
	int critical_value;

	critical_value = (data->c2 - panic_temp) / data->c1;

	regmap_write(map, soc_data->panic_alarm_ctrl + REG_CLR,
		     soc_data->panic_alarm_mask);
	regmap_write(map, soc_data->panic_alarm_ctrl + REG_SET,
		     critical_value << soc_data->panic_alarm_shift);
}

static void imx_set_alarm_temp(struct imx_thermal_data *data,
			       int alarm_temp)
{
	struct regmap *map = data->tempmon;
	const struct thermal_soc_data *soc_data = data->socdata;
	int alarm_value;

	data->alarm_temp = alarm_temp;

	if (data->socdata->version == TEMPMON_IMX7D)
		alarm_value = alarm_temp / 1000 + data->c1 - 25;
	else
		alarm_value = (data->c2 - alarm_temp) / data->c1;

	regmap_write(map, soc_data->high_alarm_ctrl + REG_CLR,
		     soc_data->high_alarm_mask);
	regmap_write(map, soc_data->high_alarm_ctrl + REG_SET,
		     alarm_value << soc_data->high_alarm_shift);
}

static int imx_get_temp(struct thermal_zone_device *tz, int *temp)
{
	struct imx_thermal_data *data = tz->devdata;
	const struct thermal_soc_data *soc_data = data->socdata;
	struct regmap *map = data->tempmon;
	unsigned int n_meas;
	bool wait;
	u32 val;

	if (data->mode == THERMAL_DEVICE_ENABLED) {
		/* Check if a measurement is currently in progress */
		regmap_read(map, soc_data->temp_data, &val);
		wait = !(val & soc_data->temp_valid_mask);
	} else {
		/*
		 * Every time we measure the temperature, we will power on the
		 * temperature sensor, enable measurements, take a reading,
		 * disable measurements, power off the temperature sensor.
		 */
		regmap_write(map, soc_data->sensor_ctrl + REG_CLR,
			    soc_data->power_down_mask);
		regmap_write(map, soc_data->sensor_ctrl + REG_SET,
			    soc_data->measure_temp_mask);

		wait = true;
	}

	/*
	 * According to the temp sensor designers, it may require up to ~17us
	 * to complete a measurement.
	 */
	if (wait)
		usleep_range(20, 50);

	regmap_read(map, soc_data->temp_data, &val);

	if (data->mode != THERMAL_DEVICE_ENABLED) {
		regmap_write(map, soc_data->sensor_ctrl + REG_CLR,
			     soc_data->measure_temp_mask);
		regmap_write(map, soc_data->sensor_ctrl + REG_SET,
			     soc_data->power_down_mask);
	}

	if ((val & soc_data->temp_valid_mask) == 0) {
		dev_dbg(&tz->device, "temp measurement never finished\n");
		return -EAGAIN;
	}

	n_meas = (val & soc_data->temp_value_mask)
		>> soc_data->temp_value_shift;

	/* See imx_init_calib() for formula derivation */
	if (data->socdata->version == TEMPMON_IMX7D)
		*temp = (n_meas - data->c1 + 25) * 1000;
	else
		*temp = data->c2 - n_meas * data->c1;

	/* Update alarm value to next higher trip point for TEMPMON_IMX6Q */
	if (data->socdata->version == TEMPMON_IMX6Q) {
		if (data->alarm_temp == data->temp_passive &&
			*temp >= data->temp_passive)
			imx_set_alarm_temp(data, data->temp_critical);
		if (data->alarm_temp == data->temp_critical &&
			*temp < data->temp_passive) {
			imx_set_alarm_temp(data, data->temp_passive);
			dev_dbg(&tz->device, "thermal alarm off: T < %d\n",
				data->alarm_temp / 1000);
		}
	}

	if (*temp != data->last_temp) {
		dev_dbg(&tz->device, "millicelsius: %d\n", *temp);
		data->last_temp = *temp;
	}

	/* Reenable alarm IRQ if temperature below alarm temperature */
	if (!data->irq_enabled && *temp < data->alarm_temp) {
		data->irq_enabled = true;
		enable_irq(data->irq);
	}

	return 0;
}

static int imx_get_mode(struct thermal_zone_device *tz,
			enum thermal_device_mode *mode)
{
	struct imx_thermal_data *data = tz->devdata;

	*mode = data->mode;

	return 0;
}

static int imx_set_mode(struct thermal_zone_device *tz,
			enum thermal_device_mode mode)
{
	struct imx_thermal_data *data = tz->devdata;
	struct regmap *map = data->tempmon;
	const struct thermal_soc_data *soc_data = data->socdata;

	if (mode == THERMAL_DEVICE_ENABLED) {
		tz->polling_delay = IMX_POLLING_DELAY;
		tz->passive_delay = IMX_PASSIVE_DELAY;

		regmap_write(map, soc_data->sensor_ctrl + REG_CLR,
			     soc_data->power_down_mask);
		regmap_write(map, soc_data->sensor_ctrl + REG_SET,
			     soc_data->measure_temp_mask);

		if (!data->irq_enabled) {
			data->irq_enabled = true;
			enable_irq(data->irq);
		}
	} else {
		regmap_write(map, soc_data->sensor_ctrl + REG_CLR,
			     soc_data->measure_temp_mask);
		regmap_write(map, soc_data->sensor_ctrl + REG_SET,
			     soc_data->power_down_mask);

		tz->polling_delay = 0;
		tz->passive_delay = 0;

		if (data->irq_enabled) {
			disable_irq(data->irq);
			data->irq_enabled = false;
		}
	}

	data->mode = mode;
	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);

	return 0;
}

static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
			     enum thermal_trip_type *type)
{
	*type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
					     THERMAL_TRIP_CRITICAL;
	return 0;
}

static int imx_get_crit_temp(struct thermal_zone_device *tz, int *temp)
{
	struct imx_thermal_data *data = tz->devdata;

	*temp = data->temp_critical;
	return 0;
}

static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
			     int *temp)
{
	struct imx_thermal_data *data = tz->devdata;

	*temp = (trip == IMX_TRIP_PASSIVE) ? data->temp_passive :
					     data->temp_critical;
	return 0;
}

static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
			     int temp)
{
	struct imx_thermal_data *data = tz->devdata;

	/* do not allow changing critical threshold */
	if (trip == IMX_TRIP_CRITICAL)
		return -EPERM;

	/* do not allow passive to be set higher than critical */
	if (temp < 0 || temp > data->temp_critical)
		return -EINVAL;

	data->temp_passive = temp;

	imx_set_alarm_temp(data, temp);

	return 0;
}

static int imx_bind(struct thermal_zone_device *tz,
		    struct thermal_cooling_device *cdev)
{
	int ret;

	ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
					       THERMAL_NO_LIMIT,
					       THERMAL_NO_LIMIT,
					       THERMAL_WEIGHT_DEFAULT);
	if (ret) {
		dev_err(&tz->device,
			"binding zone %s with cdev %s failed:%d\n",
			tz->type, cdev->type, ret);
		return ret;
	}

	return 0;
}

static int imx_unbind(struct thermal_zone_device *tz,
		      struct thermal_cooling_device *cdev)
{
	int ret;

	ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
	if (ret) {
		dev_err(&tz->device,
			"unbinding zone %s with cdev %s failed:%d\n",
			tz->type, cdev->type, ret);
		return ret;
	}

	return 0;
}

static struct thermal_zone_device_ops imx_tz_ops = {
	.bind = imx_bind,
	.unbind = imx_unbind,
	.get_temp = imx_get_temp,
	.get_mode = imx_get_mode,
	.set_mode = imx_set_mode,
	.get_trip_type = imx_get_trip_type,
	.get_trip_temp = imx_get_trip_temp,
	.get_crit_temp = imx_get_crit_temp,
	.set_trip_temp = imx_set_trip_temp,
};

static int imx_init_calib(struct platform_device *pdev, u32 ocotp_ana1)
{
	struct imx_thermal_data *data = platform_get_drvdata(pdev);
	int n1;
	u64 temp64;

	if (ocotp_ana1 == 0 || ocotp_ana1 == ~0) {
		dev_err(&pdev->dev, "invalid sensor calibration data\n");
		return -EINVAL;
	}

	/*
	 * On i.MX7D, we only use the calibration data at 25C to get the temp,
	 * Tmeas = ( Nmeas - n1) + 25; n1 is the fuse value for 25C.
	 */
	if (data->socdata->version == TEMPMON_IMX7D) {
		data->c1 = (ocotp_ana1 >> 9) & 0x1ff;
		return 0;
	}

	/*
	 * The sensor is calibrated at 25 °C (aka T1) and the value measured
	 * (aka N1) at this temperature is provided in bits [31:20] in the
	 * i.MX's OCOTP value ANA1.
	 * To find the actual temperature T, the following formula has to be used
	 * when reading value n from the sensor:
	 *
	 * T = T1 + (N - N1) / (0.4148468 - 0.0015423 * N1) °C + 3.580661 °C
	 *   = [T1' - N1 / (0.4148468 - 0.0015423 * N1) °C] + N / (0.4148468 - 0.0015423 * N1) °C
	 *   = [T1' + N1 / (0.0015423 * N1 - 0.4148468) °C] - N / (0.0015423 * N1 - 0.4148468) °C
	 *   = c2 - c1 * N
	 *
	 * with
	 *
	 *  T1' = 28.580661 °C
	 *   c1 = 1 / (0.0015423 * N1 - 0.4297157) °C
	 *   c2 = T1' + N1 / (0.0015423 * N1 - 0.4148468) °C
	 *      = T1' + N1 * c1
	 */
	n1 = ocotp_ana1 >> 20;

	temp64 = 10000000; /* use 10^7 as fixed point constant for values in formula */
	temp64 *= 1000; /* to get result in °mC */
	do_div(temp64, 15423 * n1 - 4148468);
	data->c1 = temp64;
	data->c2 = n1 * data->c1 + 28581;

	return 0;
}

static void imx_init_temp_grade(struct platform_device *pdev, u32 ocotp_mem0)
{
	struct imx_thermal_data *data = platform_get_drvdata(pdev);

	/* The maximum die temp is specified by the Temperature Grade */
	switch ((ocotp_mem0 >> 6) & 0x3) {
	case 0: /* Commercial (0 to 95 °C) */
		data->temp_grade = "Commercial";
		data->temp_max = 95000;
		break;
	case 1: /* Extended Commercial (-20 °C to 105 °C) */
		data->temp_grade = "Extended Commercial";
		data->temp_max = 105000;
		break;
	case 2: /* Industrial (-40 °C to 105 °C) */
		data->temp_grade = "Industrial";
		data->temp_max = 105000;
		break;
	case 3: /* Automotive (-40 °C to 125 °C) */
		data->temp_grade = "Automotive";
		data->temp_max = 125000;
		break;
	}

	/*
	 * Set the critical trip point at 5 °C under max
	 * Set the passive trip point at 10 °C under max (changeable via sysfs)
	 */
	data->temp_critical = data->temp_max - (1000 * 5);
	data->temp_passive = data->temp_max - (1000 * 10);
}

static int imx_init_from_tempmon_data(struct platform_device *pdev)
{
	struct regmap *map;
	int ret;
	u32 val;

	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
					      "fsl,tempmon-data");
	if (IS_ERR(map)) {
		ret = PTR_ERR(map);
		dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
		return ret;
	}

	ret = regmap_read(map, OCOTP_ANA1, &val);
	if (ret) {
		dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
		return ret;
	}
	ret = imx_init_calib(pdev, val);
	if (ret)
		return ret;

	ret = regmap_read(map, OCOTP_MEM0, &val);
	if (ret) {
		dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
		return ret;
	}
	imx_init_temp_grade(pdev, val);

	return 0;
}

static int imx_init_from_nvmem_cells(struct platform_device *pdev)
{
	int ret;
	u32 val;

	ret = nvmem_cell_read_u32(&pdev->dev, "calib", &val);
	if (ret)
		return ret;

	ret = imx_init_calib(pdev, val);
	if (ret)
		return ret;

	ret = nvmem_cell_read_u32(&pdev->dev, "temp_grade", &val);
	if (ret)
		return ret;
	imx_init_temp_grade(pdev, val);

	return 0;
}

static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
{
	struct imx_thermal_data *data = dev;

	disable_irq_nosync(irq);
	data->irq_enabled = false;

	return IRQ_WAKE_THREAD;
}

static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
{
	struct imx_thermal_data *data = dev;

	dev_dbg(&data->tz->device, "THERMAL ALARM: T > %d\n",
		data->alarm_temp / 1000);

	thermal_zone_device_update(data->tz, THERMAL_EVENT_UNSPECIFIED);

	return IRQ_HANDLED;
}

static const struct of_device_id of_imx_thermal_match[] = {
	{ .compatible = "fsl,imx6q-tempmon", .data = &thermal_imx6q_data, },
	{ .compatible = "fsl,imx6sx-tempmon", .data = &thermal_imx6sx_data, },
	{ .compatible = "fsl,imx7d-tempmon", .data = &thermal_imx7d_data, },
	{ /* end */ }
};
MODULE_DEVICE_TABLE(of, of_imx_thermal_match);

/*
 * Create cooling device in case no #cooling-cells property is available in
 * CPU node
 */
static int imx_thermal_register_legacy_cooling(struct imx_thermal_data *data)
{
	struct device_node *np = of_get_cpu_node(data->policy->cpu, NULL);
	int ret;

	if (!np || !of_find_property(np, "#cooling-cells", NULL)) {
		data->cdev = cpufreq_cooling_register(data->policy);
		if (IS_ERR(data->cdev)) {
			ret = PTR_ERR(data->cdev);
			cpufreq_cpu_put(data->policy);
			return ret;
		}
	}

	return 0;
}

static int imx_thermal_probe(struct platform_device *pdev)
{
	struct imx_thermal_data *data;
	struct regmap *map;
	int measure_freq;
	int ret;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
	if (IS_ERR(map)) {
		ret = PTR_ERR(map);
		dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
		return ret;
	}
	data->tempmon = map;

	data->socdata = of_device_get_match_data(&pdev->dev);
	if (!data->socdata) {
		dev_err(&pdev->dev, "no device match found\n");
		return -ENODEV;
	}

	/* make sure the IRQ flag is clear before enabling irq on i.MX6SX */
	if (data->socdata->version == TEMPMON_IMX6SX) {
		regmap_write(map, IMX6_MISC1 + REG_CLR,
			IMX6_MISC1_IRQ_TEMPHIGH | IMX6_MISC1_IRQ_TEMPLOW
			| IMX6_MISC1_IRQ_TEMPPANIC);
		/*
		 * reset value of LOW ALARM is incorrect, set it to lowest
		 * value to avoid false trigger of low alarm.
		 */
		regmap_write(map, data->socdata->low_alarm_ctrl + REG_SET,
			     data->socdata->low_alarm_mask);
	}

	data->irq = platform_get_irq(pdev, 0);
	if (data->irq < 0)
		return data->irq;

	platform_set_drvdata(pdev, data);

	if (of_find_property(pdev->dev.of_node, "nvmem-cells", NULL)) {
		ret = imx_init_from_nvmem_cells(pdev);
		if (ret == -EPROBE_DEFER)
			return ret;
		if (ret) {
			dev_err(&pdev->dev, "failed to init from nvmem: %d\n",
				ret);
			return ret;
		}
	} else {
		ret = imx_init_from_tempmon_data(pdev);
		if (ret) {
			dev_err(&pdev->dev, "failed to init from from fsl,tempmon-data\n");
			return ret;
		}
	}

	/* Make sure sensor is in known good state for measurements */
	regmap_write(map, data->socdata->sensor_ctrl + REG_CLR,
		     data->socdata->power_down_mask);
	regmap_write(map, data->socdata->sensor_ctrl + REG_CLR,
		     data->socdata->measure_temp_mask);
	regmap_write(map, data->socdata->measure_freq_ctrl + REG_CLR,
		     data->socdata->measure_freq_mask);
	if (data->socdata->version != TEMPMON_IMX7D)
		regmap_write(map, IMX6_MISC0 + REG_SET,
			IMX6_MISC0_REFTOP_SELBIASOFF);
	regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
		     data->socdata->power_down_mask);

	data->policy = cpufreq_cpu_get(0);
	if (!data->policy) {
		pr_debug("%s: CPUFreq policy not found\n", __func__);
		return -EPROBE_DEFER;
	}

	ret = imx_thermal_register_legacy_cooling(data);
	if (ret) {
		dev_err(&pdev->dev,
			"failed to register cpufreq cooling device: %d\n", ret);
		return ret;
	}

	data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(data->thermal_clk)) {
		ret = PTR_ERR(data->thermal_clk);
		if (ret != -EPROBE_DEFER)
			dev_err(&pdev->dev,
				"failed to get thermal clk: %d\n", ret);
		cpufreq_cooling_unregister(data->cdev);
		cpufreq_cpu_put(data->policy);
		return ret;
	}

	/*
	 * Thermal sensor needs clk on to get correct value, normally
	 * we should enable its clk before taking measurement and disable
	 * clk after measurement is done, but if alarm function is enabled,
	 * hardware will auto measure the temperature periodically, so we
	 * need to keep the clk always on for alarm function.
	 */
	ret = clk_prepare_enable(data->thermal_clk);
	if (ret) {
		dev_err(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
		cpufreq_cooling_unregister(data->cdev);
		cpufreq_cpu_put(data->policy);
		return ret;
	}

	data->tz = thermal_zone_device_register("imx_thermal_zone",
						IMX_TRIP_NUM,
						BIT(IMX_TRIP_PASSIVE), data,
						&imx_tz_ops, NULL,
						IMX_PASSIVE_DELAY,
						IMX_POLLING_DELAY);
	if (IS_ERR(data->tz)) {
		ret = PTR_ERR(data->tz);
		dev_err(&pdev->dev,
			"failed to register thermal zone device %d\n", ret);
		clk_disable_unprepare(data->thermal_clk);
		cpufreq_cooling_unregister(data->cdev);
		cpufreq_cpu_put(data->policy);
		return ret;
	}

	dev_info(&pdev->dev, "%s CPU temperature grade - max:%dC"
		 " critical:%dC passive:%dC\n", data->temp_grade,
		 data->temp_max / 1000, data->temp_critical / 1000,
		 data->temp_passive / 1000);

	/* Enable measurements at ~ 10 Hz */
	regmap_write(map, data->socdata->measure_freq_ctrl + REG_CLR,
		     data->socdata->measure_freq_mask);
	measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
	regmap_write(map, data->socdata->measure_freq_ctrl + REG_SET,
		     measure_freq << data->socdata->measure_freq_shift);
	imx_set_alarm_temp(data, data->temp_passive);

	if (data->socdata->version == TEMPMON_IMX6SX)
		imx_set_panic_temp(data, data->temp_critical);

	regmap_write(map, data->socdata->sensor_ctrl + REG_CLR,
		     data->socdata->power_down_mask);
	regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
		     data->socdata->measure_temp_mask);

	data->irq_enabled = true;
	data->mode = THERMAL_DEVICE_ENABLED;

	ret = devm_request_threaded_irq(&pdev->dev, data->irq,
			imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
			0, "imx_thermal", data);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
		clk_disable_unprepare(data->thermal_clk);
		thermal_zone_device_unregister(data->tz);
		cpufreq_cooling_unregister(data->cdev);
		cpufreq_cpu_put(data->policy);
		return ret;
	}

	return 0;
}

static int imx_thermal_remove(struct platform_device *pdev)
{
	struct imx_thermal_data *data = platform_get_drvdata(pdev);
	struct regmap *map = data->tempmon;

	/* Disable measurements */
	regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
		     data->socdata->power_down_mask);
	if (!IS_ERR(data->thermal_clk))
		clk_disable_unprepare(data->thermal_clk);

	thermal_zone_device_unregister(data->tz);
	cpufreq_cooling_unregister(data->cdev);
	cpufreq_cpu_put(data->policy);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int imx_thermal_suspend(struct device *dev)
{
	struct imx_thermal_data *data = dev_get_drvdata(dev);
	struct regmap *map = data->tempmon;

	/*
	 * Need to disable thermal sensor, otherwise, when thermal core
	 * try to get temperature before thermal sensor resume, a wrong
	 * temperature will be read as the thermal sensor is powered
	 * down.
	 */
	regmap_write(map, data->socdata->sensor_ctrl + REG_CLR,
		     data->socdata->measure_temp_mask);
	regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
		     data->socdata->power_down_mask);
	data->mode = THERMAL_DEVICE_DISABLED;
	clk_disable_unprepare(data->thermal_clk);

	return 0;
}

static int imx_thermal_resume(struct device *dev)
{
	struct imx_thermal_data *data = dev_get_drvdata(dev);
	struct regmap *map = data->tempmon;
	int ret;

	ret = clk_prepare_enable(data->thermal_clk);
	if (ret)
		return ret;
	/* Enabled thermal sensor after resume */
	regmap_write(map, data->socdata->sensor_ctrl + REG_CLR,
		     data->socdata->power_down_mask);
	regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
		     data->socdata->measure_temp_mask);
	data->mode = THERMAL_DEVICE_ENABLED;

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
			 imx_thermal_suspend, imx_thermal_resume);

static struct platform_driver imx_thermal = {
	.driver = {
		.name	= "imx_thermal",
		.pm	= &imx_thermal_pm_ops,
		.of_match_table = of_imx_thermal_match,
	},
	.probe		= imx_thermal_probe,
	.remove		= imx_thermal_remove,
};
module_platform_driver(imx_thermal);

MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:imx-thermal");
OpenPOWER on IntegriCloud