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  1/*
  2 * Copyright 2013 Freescale Semiconductor, Inc.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 *
  8 */
  9
 10#include <linux/clk.h>
 11#include <linux/cpu_cooling.h>
 12#include <linux/delay.h>
 13#include <linux/device.h>
 14#include <linux/init.h>
 15#include <linux/interrupt.h>
 16#include <linux/io.h>
 17#include <linux/kernel.h>
 18#include <linux/mfd/syscon.h>
 19#include <linux/module.h>
 20#include <linux/of.h>
 21#include <linux/of_device.h>
 22#include <linux/platform_device.h>
 23#include <linux/regmap.h>
 24#include <linux/slab.h>
 25#include <linux/thermal.h>
 26#include <linux/types.h>
 27
 28#define REG_SET		0x4
 29#define REG_CLR		0x8
 30#define REG_TOG		0xc
 31
 32#define MISC0				0x0150
 33#define MISC0_REFTOP_SELBIASOFF		(1 << 3)
 34#define MISC1				0x0160
 35#define MISC1_IRQ_TEMPHIGH		(1 << 29)
 36/* Below LOW and PANIC bits are only for TEMPMON_IMX6SX */
 37#define MISC1_IRQ_TEMPLOW		(1 << 28)
 38#define MISC1_IRQ_TEMPPANIC		(1 << 27)
 39
 40#define TEMPSENSE0			0x0180
 41#define TEMPSENSE0_ALARM_VALUE_SHIFT	20
 42#define TEMPSENSE0_ALARM_VALUE_MASK	(0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
 43#define TEMPSENSE0_TEMP_CNT_SHIFT	8
 44#define TEMPSENSE0_TEMP_CNT_MASK	(0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
 45#define TEMPSENSE0_FINISHED		(1 << 2)
 46#define TEMPSENSE0_MEASURE_TEMP		(1 << 1)
 47#define TEMPSENSE0_POWER_DOWN		(1 << 0)
 48
 49#define TEMPSENSE1			0x0190
 50#define TEMPSENSE1_MEASURE_FREQ		0xffff
 51/* Below TEMPSENSE2 is only for TEMPMON_IMX6SX */
 52#define TEMPSENSE2			0x0290
 53#define TEMPSENSE2_LOW_VALUE_SHIFT	0
 54#define TEMPSENSE2_LOW_VALUE_MASK	0xfff
 55#define TEMPSENSE2_PANIC_VALUE_SHIFT	16
 56#define TEMPSENSE2_PANIC_VALUE_MASK	0xfff0000
 57
 58#define OCOTP_MEM0			0x0480
 59#define OCOTP_ANA1			0x04e0
 60
 61/* The driver supports 1 passive trip point and 1 critical trip point */
 62enum imx_thermal_trip {
 63	IMX_TRIP_PASSIVE,
 64	IMX_TRIP_CRITICAL,
 65	IMX_TRIP_NUM,
 66};
 67
 68#define IMX_POLLING_DELAY		2000 /* millisecond */
 69#define IMX_PASSIVE_DELAY		1000
 70
 71#define FACTOR0				10000000
 72#define FACTOR1				15976
 73#define FACTOR2				4297157
 74
 75#define TEMPMON_IMX6Q			1
 76#define TEMPMON_IMX6SX			2
 77
 78struct thermal_soc_data {
 79	u32 version;
 80};
 81
 82static struct thermal_soc_data thermal_imx6q_data = {
 83	.version = TEMPMON_IMX6Q,
 84};
 85
 86static struct thermal_soc_data thermal_imx6sx_data = {
 87	.version = TEMPMON_IMX6SX,
 88};
 89
 90struct imx_thermal_data {
 91	struct thermal_zone_device *tz;
 92	struct thermal_cooling_device *cdev;
 93	enum thermal_device_mode mode;
 94	struct regmap *tempmon;
 95	u32 c1, c2; /* See formula in imx_get_sensor_data() */
 96	int temp_passive;
 97	int temp_critical;
 98	int temp_max;
 99	int alarm_temp;
100	int last_temp;
101	bool irq_enabled;
102	int irq;
103	struct clk *thermal_clk;
104	const struct thermal_soc_data *socdata;
105	const char *temp_grade;
106};
107
108static void imx_set_panic_temp(struct imx_thermal_data *data,
109			       int panic_temp)
110{
111	struct regmap *map = data->tempmon;
112	int critical_value;
113
114	critical_value = (data->c2 - panic_temp) / data->c1;
115	regmap_write(map, TEMPSENSE2 + REG_CLR, TEMPSENSE2_PANIC_VALUE_MASK);
116	regmap_write(map, TEMPSENSE2 + REG_SET, critical_value <<
117			TEMPSENSE2_PANIC_VALUE_SHIFT);
118}
119
120static void imx_set_alarm_temp(struct imx_thermal_data *data,
121			       int alarm_temp)
122{
123	struct regmap *map = data->tempmon;
124	int alarm_value;
125
126	data->alarm_temp = alarm_temp;
127	alarm_value = (data->c2 - alarm_temp) / data->c1;
128	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
129	regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
130			TEMPSENSE0_ALARM_VALUE_SHIFT);
131}
132
133static int imx_get_temp(struct thermal_zone_device *tz, int *temp)
134{
135	struct imx_thermal_data *data = tz->devdata;
136	struct regmap *map = data->tempmon;
137	unsigned int n_meas;
138	bool wait;
139	u32 val;
140
141	if (data->mode == THERMAL_DEVICE_ENABLED) {
142		/* Check if a measurement is currently in progress */
143		regmap_read(map, TEMPSENSE0, &val);
144		wait = !(val & TEMPSENSE0_FINISHED);
145	} else {
146		/*
147		 * Every time we measure the temperature, we will power on the
148		 * temperature sensor, enable measurements, take a reading,
149		 * disable measurements, power off the temperature sensor.
150		 */
151		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
152		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
153
154		wait = true;
155	}
156
157	/*
158	 * According to the temp sensor designers, it may require up to ~17us
159	 * to complete a measurement.
160	 */
161	if (wait)
162		usleep_range(20, 50);
163
164	regmap_read(map, TEMPSENSE0, &val);
165
166	if (data->mode != THERMAL_DEVICE_ENABLED) {
167		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
168		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
169	}
170
171	if ((val & TEMPSENSE0_FINISHED) == 0) {
172		dev_dbg(&tz->device, "temp measurement never finished\n");
173		return -EAGAIN;
174	}
175
176	n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
177
178	/* See imx_get_sensor_data() for formula derivation */
179	*temp = data->c2 - n_meas * data->c1;
180
181	/* Update alarm value to next higher trip point for TEMPMON_IMX6Q */
182	if (data->socdata->version == TEMPMON_IMX6Q) {
183		if (data->alarm_temp == data->temp_passive &&
184			*temp >= data->temp_passive)
185			imx_set_alarm_temp(data, data->temp_critical);
186		if (data->alarm_temp == data->temp_critical &&
187			*temp < data->temp_passive) {
188			imx_set_alarm_temp(data, data->temp_passive);
189			dev_dbg(&tz->device, "thermal alarm off: T < %d\n",
190				data->alarm_temp / 1000);
191		}
192	}
193
194	if (*temp != data->last_temp) {
195		dev_dbg(&tz->device, "millicelsius: %d\n", *temp);
196		data->last_temp = *temp;
197	}
198
199	/* Reenable alarm IRQ if temperature below alarm temperature */
200	if (!data->irq_enabled && *temp < data->alarm_temp) {
201		data->irq_enabled = true;
202		enable_irq(data->irq);
203	}
204
205	return 0;
206}
207
208static int imx_get_mode(struct thermal_zone_device *tz,
209			enum thermal_device_mode *mode)
210{
211	struct imx_thermal_data *data = tz->devdata;
212
213	*mode = data->mode;
214
215	return 0;
216}
217
218static int imx_set_mode(struct thermal_zone_device *tz,
219			enum thermal_device_mode mode)
220{
221	struct imx_thermal_data *data = tz->devdata;
222	struct regmap *map = data->tempmon;
223
224	if (mode == THERMAL_DEVICE_ENABLED) {
225		tz->polling_delay = IMX_POLLING_DELAY;
226		tz->passive_delay = IMX_PASSIVE_DELAY;
227
228		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
229		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
230
231		if (!data->irq_enabled) {
232			data->irq_enabled = true;
233			enable_irq(data->irq);
234		}
235	} else {
236		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
237		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
238
239		tz->polling_delay = 0;
240		tz->passive_delay = 0;
241
242		if (data->irq_enabled) {
243			disable_irq(data->irq);
244			data->irq_enabled = false;
245		}
246	}
247
248	data->mode = mode;
249	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
250
251	return 0;
252}
253
254static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
255			     enum thermal_trip_type *type)
256{
257	*type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
258					     THERMAL_TRIP_CRITICAL;
259	return 0;
260}
261
262static int imx_get_crit_temp(struct thermal_zone_device *tz, int *temp)
263{
264	struct imx_thermal_data *data = tz->devdata;
265
266	*temp = data->temp_critical;
267	return 0;
268}
269
270static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
271			     int *temp)
272{
273	struct imx_thermal_data *data = tz->devdata;
274
275	*temp = (trip == IMX_TRIP_PASSIVE) ? data->temp_passive :
276					     data->temp_critical;
277	return 0;
278}
279
280static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
281			     int temp)
282{
283	struct imx_thermal_data *data = tz->devdata;
284
285	/* do not allow changing critical threshold */
286	if (trip == IMX_TRIP_CRITICAL)
287		return -EPERM;
288
289	/* do not allow passive to be set higher than critical */
290	if (temp < 0 || temp > data->temp_critical)
291		return -EINVAL;
292
293	data->temp_passive = temp;
294
295	imx_set_alarm_temp(data, temp);
296
297	return 0;
298}
299
300static int imx_bind(struct thermal_zone_device *tz,
301		    struct thermal_cooling_device *cdev)
302{
303	int ret;
304
305	ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
306					       THERMAL_NO_LIMIT,
307					       THERMAL_NO_LIMIT,
308					       THERMAL_WEIGHT_DEFAULT);
309	if (ret) {
310		dev_err(&tz->device,
311			"binding zone %s with cdev %s failed:%d\n",
312			tz->type, cdev->type, ret);
313		return ret;
314	}
315
316	return 0;
317}
318
319static int imx_unbind(struct thermal_zone_device *tz,
320		      struct thermal_cooling_device *cdev)
321{
322	int ret;
323
324	ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
325	if (ret) {
326		dev_err(&tz->device,
327			"unbinding zone %s with cdev %s failed:%d\n",
328			tz->type, cdev->type, ret);
329		return ret;
330	}
331
332	return 0;
333}
334
335static struct thermal_zone_device_ops imx_tz_ops = {
336	.bind = imx_bind,
337	.unbind = imx_unbind,
338	.get_temp = imx_get_temp,
339	.get_mode = imx_get_mode,
340	.set_mode = imx_set_mode,
341	.get_trip_type = imx_get_trip_type,
342	.get_trip_temp = imx_get_trip_temp,
343	.get_crit_temp = imx_get_crit_temp,
344	.set_trip_temp = imx_set_trip_temp,
345};
346
347static int imx_get_sensor_data(struct platform_device *pdev)
348{
349	struct imx_thermal_data *data = platform_get_drvdata(pdev);
350	struct regmap *map;
351	int t1, n1;
352	int ret;
353	u32 val;
354	u64 temp64;
355
356	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
357					      "fsl,tempmon-data");
358	if (IS_ERR(map)) {
359		ret = PTR_ERR(map);
360		dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
361		return ret;
362	}
363
364	ret = regmap_read(map, OCOTP_ANA1, &val);
365	if (ret) {
366		dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
367		return ret;
368	}
369
370	if (val == 0 || val == ~0) {
371		dev_err(&pdev->dev, "invalid sensor calibration data\n");
372		return -EINVAL;
373	}
374
375	/*
376	 * Sensor data layout:
377	 *   [31:20] - sensor value @ 25C
378	 * Use universal formula now and only need sensor value @ 25C
379	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
380	 */
381	n1 = val >> 20;
382	t1 = 25; /* t1 always 25C */
383
384	/*
385	 * Derived from linear interpolation:
386	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
387	 * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
388	 * (Nmeas - n1) / (Tmeas - t1) = slope
389	 * We want to reduce this down to the minimum computation necessary
390	 * for each temperature read.  Also, we want Tmeas in millicelsius
391	 * and we don't want to lose precision from integer division. So...
392	 * Tmeas = (Nmeas - n1) / slope + t1
393	 * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
394	 * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
395	 * Let constant c1 = (-1000 / slope)
396	 * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
397	 * Let constant c2 = n1 *c1 + 1000 * t1
398	 * milli_Tmeas = c2 - Nmeas * c1
399	 */
400	temp64 = FACTOR0;
401	temp64 *= 1000;
402	do_div(temp64, FACTOR1 * n1 - FACTOR2);
403	data->c1 = temp64;
404	data->c2 = n1 * data->c1 + 1000 * t1;
405
406	/* use OTP for thermal grade */
407	ret = regmap_read(map, OCOTP_MEM0, &val);
408	if (ret) {
409		dev_err(&pdev->dev, "failed to read temp grade: %d\n", ret);
410		return ret;
411	}
412
413	/* The maximum die temp is specified by the Temperature Grade */
414	switch ((val >> 6) & 0x3) {
415	case 0: /* Commercial (0 to 95C) */
416		data->temp_grade = "Commercial";
417		data->temp_max = 95000;
418		break;
419	case 1: /* Extended Commercial (-20 to 105C) */
420		data->temp_grade = "Extended Commercial";
421		data->temp_max = 105000;
422		break;
423	case 2: /* Industrial (-40 to 105C) */
424		data->temp_grade = "Industrial";
425		data->temp_max = 105000;
426		break;
427	case 3: /* Automotive (-40 to 125C) */
428		data->temp_grade = "Automotive";
429		data->temp_max = 125000;
430		break;
431	}
432
433	/*
434	 * Set the critical trip point at 5C under max
435	 * Set the passive trip point at 10C under max (can change via sysfs)
436	 */
437	data->temp_critical = data->temp_max - (1000 * 5);
438	data->temp_passive = data->temp_max - (1000 * 10);
439
440	return 0;
441}
442
443static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
444{
445	struct imx_thermal_data *data = dev;
446
447	disable_irq_nosync(irq);
448	data->irq_enabled = false;
449
450	return IRQ_WAKE_THREAD;
451}
452
453static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
454{
455	struct imx_thermal_data *data = dev;
456
457	dev_dbg(&data->tz->device, "THERMAL ALARM: T > %d\n",
458		data->alarm_temp / 1000);
459
460	thermal_zone_device_update(data->tz, THERMAL_EVENT_UNSPECIFIED);
461
462	return IRQ_HANDLED;
463}
464
465static const struct of_device_id of_imx_thermal_match[] = {
466	{ .compatible = "fsl,imx6q-tempmon", .data = &thermal_imx6q_data, },
467	{ .compatible = "fsl,imx6sx-tempmon", .data = &thermal_imx6sx_data, },
468	{ /* end */ }
469};
470MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
471
472static int imx_thermal_probe(struct platform_device *pdev)
473{
474	struct imx_thermal_data *data;
475	struct regmap *map;
476	int measure_freq;
477	int ret;
478
479	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
480	if (!data)
481		return -ENOMEM;
482
483	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
484	if (IS_ERR(map)) {
485		ret = PTR_ERR(map);
486		dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
487		return ret;
488	}
489	data->tempmon = map;
490
491	data->socdata = of_device_get_match_data(&pdev->dev);
492
493	/* make sure the IRQ flag is clear before enabling irq on i.MX6SX */
494	if (data->socdata->version == TEMPMON_IMX6SX) {
495		regmap_write(map, MISC1 + REG_CLR, MISC1_IRQ_TEMPHIGH |
496			MISC1_IRQ_TEMPLOW | MISC1_IRQ_TEMPPANIC);
497		/*
498		 * reset value of LOW ALARM is incorrect, set it to lowest
499		 * value to avoid false trigger of low alarm.
500		 */
501		regmap_write(map, TEMPSENSE2 + REG_SET,
502			TEMPSENSE2_LOW_VALUE_MASK);
503	}
504
505	data->irq = platform_get_irq(pdev, 0);
506	if (data->irq < 0)
507		return data->irq;
508
509	platform_set_drvdata(pdev, data);
510
511	ret = imx_get_sensor_data(pdev);
512	if (ret) {
513		dev_err(&pdev->dev, "failed to get sensor data\n");
514		return ret;
515	}
516
517	/* Make sure sensor is in known good state for measurements */
518	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
519	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
520	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
521	regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
522	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
523
524	data->cdev = cpufreq_cooling_register(cpu_present_mask);
525	if (IS_ERR(data->cdev)) {
526		ret = PTR_ERR(data->cdev);
527		if (ret != -EPROBE_DEFER)
528			dev_err(&pdev->dev,
529				"failed to register cpufreq cooling device: %d\n",
530				ret);
531		return ret;
532	}
533
534	data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
535	if (IS_ERR(data->thermal_clk)) {
536		ret = PTR_ERR(data->thermal_clk);
537		if (ret != -EPROBE_DEFER)
538			dev_err(&pdev->dev,
539				"failed to get thermal clk: %d\n", ret);
540		cpufreq_cooling_unregister(data->cdev);
541		return ret;
542	}
543
544	/*
545	 * Thermal sensor needs clk on to get correct value, normally
546	 * we should enable its clk before taking measurement and disable
547	 * clk after measurement is done, but if alarm function is enabled,
548	 * hardware will auto measure the temperature periodically, so we
549	 * need to keep the clk always on for alarm function.
550	 */
551	ret = clk_prepare_enable(data->thermal_clk);
552	if (ret) {
553		dev_err(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
554		cpufreq_cooling_unregister(data->cdev);
555		return ret;
556	}
557
558	data->tz = thermal_zone_device_register("imx_thermal_zone",
559						IMX_TRIP_NUM,
560						BIT(IMX_TRIP_PASSIVE), data,
561						&imx_tz_ops, NULL,
562						IMX_PASSIVE_DELAY,
563						IMX_POLLING_DELAY);
564	if (IS_ERR(data->tz)) {
565		ret = PTR_ERR(data->tz);
566		dev_err(&pdev->dev,
567			"failed to register thermal zone device %d\n", ret);
568		clk_disable_unprepare(data->thermal_clk);
569		cpufreq_cooling_unregister(data->cdev);
570		return ret;
571	}
572
573	dev_info(&pdev->dev, "%s CPU temperature grade - max:%dC"
574		 " critical:%dC passive:%dC\n", data->temp_grade,
575		 data->temp_max / 1000, data->temp_critical / 1000,
576		 data->temp_passive / 1000);
577
578	/* Enable measurements at ~ 10 Hz */
579	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
580	measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
581	regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
582	imx_set_alarm_temp(data, data->temp_passive);
583
584	if (data->socdata->version == TEMPMON_IMX6SX)
585		imx_set_panic_temp(data, data->temp_critical);
586
587	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
588	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
589
590	ret = devm_request_threaded_irq(&pdev->dev, data->irq,
591			imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
592			0, "imx_thermal", data);
593	if (ret < 0) {
594		dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
595		clk_disable_unprepare(data->thermal_clk);
596		thermal_zone_device_unregister(data->tz);
597		cpufreq_cooling_unregister(data->cdev);
598		return ret;
599	}
600
601	data->irq_enabled = true;
602	data->mode = THERMAL_DEVICE_ENABLED;
603
604	return 0;
605}
606
607static int imx_thermal_remove(struct platform_device *pdev)
608{
609	struct imx_thermal_data *data = platform_get_drvdata(pdev);
610	struct regmap *map = data->tempmon;
611
612	/* Disable measurements */
613	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
614	if (!IS_ERR(data->thermal_clk))
615		clk_disable_unprepare(data->thermal_clk);
616
617	thermal_zone_device_unregister(data->tz);
618	cpufreq_cooling_unregister(data->cdev);
619
620	return 0;
621}
622
623#ifdef CONFIG_PM_SLEEP
624static int imx_thermal_suspend(struct device *dev)
625{
626	struct imx_thermal_data *data = dev_get_drvdata(dev);
627	struct regmap *map = data->tempmon;
628
629	/*
630	 * Need to disable thermal sensor, otherwise, when thermal core
631	 * try to get temperature before thermal sensor resume, a wrong
632	 * temperature will be read as the thermal sensor is powered
633	 * down.
634	 */
635	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
636	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
637	data->mode = THERMAL_DEVICE_DISABLED;
638	clk_disable_unprepare(data->thermal_clk);
639
640	return 0;
641}
642
643static int imx_thermal_resume(struct device *dev)
644{
645	struct imx_thermal_data *data = dev_get_drvdata(dev);
646	struct regmap *map = data->tempmon;
647
648	clk_prepare_enable(data->thermal_clk);
649	/* Enabled thermal sensor after resume */
650	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
651	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
652	data->mode = THERMAL_DEVICE_ENABLED;
653
654	return 0;
655}
656#endif
657
658static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
659			 imx_thermal_suspend, imx_thermal_resume);
660
661static struct platform_driver imx_thermal = {
662	.driver = {
663		.name	= "imx_thermal",
664		.pm	= &imx_thermal_pm_ops,
665		.of_match_table = of_imx_thermal_match,
666	},
667	.probe		= imx_thermal_probe,
668	.remove		= imx_thermal_remove,
669};
670module_platform_driver(imx_thermal);
671
672MODULE_AUTHOR("Freescale Semiconductor, Inc.");
673MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
674MODULE_LICENSE("GPL v2");
675MODULE_ALIAS("platform:imx-thermal");