[linux-block.git] / drivers / thermal / imx_thermal.c

/*
 * Copyright 2013 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/clk.h>
#include <linux/cpu_cooling.h>
#include <linux/cpufreq.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/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/thermal.h>
#include <linux/types.h>

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

#define MISC0				0x0150
#define MISC0_REFTOP_SELBIASOFF		(1 << 3)

#define TEMPSENSE0			0x0180
#define TEMPSENSE0_ALARM_VALUE_SHIFT	20
#define TEMPSENSE0_ALARM_VALUE_MASK	(0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
#define TEMPSENSE0_TEMP_CNT_SHIFT	8
#define TEMPSENSE0_TEMP_CNT_MASK	(0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
#define TEMPSENSE0_FINISHED		(1 << 2)
#define TEMPSENSE0_MEASURE_TEMP		(1 << 1)
#define TEMPSENSE0_POWER_DOWN		(1 << 0)

#define TEMPSENSE1			0x0190
#define TEMPSENSE1_MEASURE_FREQ		0xffff

#define OCOTP_ANA1			0x04e0

/* 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,
};

/*
 * It defines the temperature in millicelsius for passive trip point
 * that will trigger cooling action when crossed.
 */
#define IMX_TEMP_PASSIVE		85000

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

#define FACTOR0				10000000
#define FACTOR1				15976
#define FACTOR2				4297157

struct imx_thermal_data {
	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_get_sensor_data() */
	unsigned long temp_passive;
	unsigned long temp_critical;
	unsigned long alarm_temp;
	unsigned long last_temp;
	bool irq_enabled;
	int irq;
	struct clk *thermal_clk;
};

static void imx_set_alarm_temp(struct imx_thermal_data *data,
			       signed long alarm_temp)
{
	struct regmap *map = data->tempmon;
	int alarm_value;

	data->alarm_temp = alarm_temp;
	alarm_value = (data->c2 - alarm_temp) / data->c1;
	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
	regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
			TEMPSENSE0_ALARM_VALUE_SHIFT);
}

static int imx_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
{
	struct imx_thermal_data *data = tz->devdata;
	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, TEMPSENSE0, &val);
		wait = !(val & TEMPSENSE0_FINISHED);
	} 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, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);

		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, TEMPSENSE0, &val);

	if (data->mode != THERMAL_DEVICE_ENABLED) {
		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	}

	if ((val & TEMPSENSE0_FINISHED) == 0) {
		dev_dbg(&tz->device, "temp measurement never finished\n");
		return -EAGAIN;
	}

	n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;

	/* See imx_get_sensor_data() for formula derivation */
	*temp = data->c2 - n_meas * data->c1;

	/* Update alarm value to next higher trip point */
	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 < %lu\n",
			data->alarm_temp / 1000);
	}

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

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

		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);

		if (!data->irq_enabled) {
			data->irq_enabled = true;
			enable_irq(data->irq);
		}
	} else {
		regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
		regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);

		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);

	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,
			     unsigned long *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,
			     unsigned long *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,
			     unsigned long temp)
{
	struct imx_thermal_data *data = tz->devdata;

	if (trip == IMX_TRIP_CRITICAL)
		return -EPERM;

	if (temp > IMX_TEMP_PASSIVE)
		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);
	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_get_sensor_data(struct platform_device *pdev)
{
	struct imx_thermal_data *data = platform_get_drvdata(pdev);
	struct regmap *map;
	int t1, n1;
	int ret;
	u32 val;
	u64 temp64;

	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;
	}

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

	/*
	 * Sensor data layout:
	 *   [31:20] - sensor value @ 25C
	 * Use universal formula now and only need sensor value @ 25C
	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
	 */
	n1 = val >> 20;
	t1 = 25; /* t1 always 25C */

	/*
	 * Derived from linear interpolation:
	 * slope = 0.4297157 - (0.0015976 * 25C fuse)
	 * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
	 * (Nmeas - n1) / (Tmeas - t1) = slope
	 * We want to reduce this down to the minimum computation necessary
	 * for each temperature read.  Also, we want Tmeas in millicelsius
	 * and we don't want to lose precision from integer division. So...
	 * Tmeas = (Nmeas - n1) / slope + t1
	 * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
	 * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
	 * Let constant c1 = (-1000 / slope)
	 * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
	 * Let constant c2 = n1 *c1 + 1000 * t1
	 * milli_Tmeas = c2 - Nmeas * c1
	 */
	temp64 = FACTOR0;
	temp64 *= 1000;
	do_div(temp64, FACTOR1 * n1 - FACTOR2);
	data->c1 = temp64;
	data->c2 = n1 * data->c1 + 1000 * t1;

	/*
	 * Set the default passive cooling trip point,
	 * can be changed from userspace.
	 */
	data->temp_passive = IMX_TEMP_PASSIVE;

	/*
	 * The maximum die temperature set to 20 C higher than
	 * IMX_TEMP_PASSIVE.
	 */
	data->temp_critical = 1000 * 20 + data->temp_passive;

	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 > %lu\n",
		data->alarm_temp / 1000);

	thermal_zone_device_update(data->tz);

	return IRQ_HANDLED;
}

static int imx_thermal_probe(struct platform_device *pdev)
{
	struct imx_thermal_data *data;
	struct cpumask clip_cpus;
	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->irq = platform_get_irq(pdev, 0);
	if (data->irq < 0)
		return data->irq;

	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);
		return ret;
	}

	platform_set_drvdata(pdev, data);

	ret = imx_get_sensor_data(pdev);
	if (ret) {
		dev_err(&pdev->dev, "failed to get sensor data\n");
		return ret;
	}

	/* Make sure sensor is in known good state for measurements */
	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
	regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);

	cpumask_set_cpu(0, &clip_cpus);
	data->cdev = cpufreq_cooling_register(&clip_cpus);
	if (IS_ERR(data->cdev)) {
		ret = PTR_ERR(data->cdev);
		dev_err(&pdev->dev,
			"failed to register cpufreq cooling device: %d\n", ret);
		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);
		cpufreq_cooling_unregister(data->cdev);
		return ret;
	}

	data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(data->thermal_clk)) {
		dev_warn(&pdev->dev, "failed to get thermal clk!\n");
	} else {
		/*
		 * 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_warn(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
	}

	/* Enable measurements at ~ 10 Hz */
	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
	measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
	regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
	imx_set_alarm_temp(data, data->temp_passive);
	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);

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

	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, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	if (!IS_ERR(data->thermal_clk))
		clk_disable_unprepare(data->thermal_clk);

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

	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, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	data->mode = THERMAL_DEVICE_DISABLED;

	return 0;
}

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

	/* Enabled thermal sensor after resume */
	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
	data->mode = THERMAL_DEVICE_ENABLED;

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
			 imx_thermal_suspend, imx_thermal_resume);

static const struct of_device_id of_imx_thermal_match[] = {
	{ .compatible = "fsl,imx6q-tempmon", },
	{ /* end */ }
};
MODULE_DEVICE_TABLE(of, of_imx_thermal_match);

static struct platform_driver imx_thermal = {
	.driver = {
		.name	= "imx_thermal",
		.owner  = THIS_MODULE,
		.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");
Commit	Line	Data
ca3de46b SG	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
329fe7b1	10	#include <linux/clk.h>
ca3de46b SG	11	#include <linux/cpu_cooling.h>
	12	#include <linux/cpufreq.h>
	13	#include <linux/delay.h>
	14	#include <linux/device.h>
	15	#include <linux/init.h>
37713a1e	16	#include <linux/interrupt.h>
ca3de46b SG	17	#include <linux/io.h>
	18	#include <linux/kernel.h>
	19	#include <linux/mfd/syscon.h>
	20	#include <linux/module.h>
	21	#include <linux/of.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
	35	#define TEMPSENSE0 0x0180
37713a1e PZ	36	#define TEMPSENSE0_ALARM_VALUE_SHIFT 20
37713a1e PZ	37	#define TEMPSENSE0_ALARM_VALUE_MASK (0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
ca3de46b SG	38	#define TEMPSENSE0_TEMP_CNT_SHIFT 8
	39	#define TEMPSENSE0_TEMP_CNT_MASK (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
	40	#define TEMPSENSE0_FINISHED (1 << 2)
	41	#define TEMPSENSE0_MEASURE_TEMP (1 << 1)
	42	#define TEMPSENSE0_POWER_DOWN (1 << 0)
	43
	44	#define TEMPSENSE1 0x0190
	45	#define TEMPSENSE1_MEASURE_FREQ 0xffff
	46
	47	#define OCOTP_ANA1 0x04e0
	48
	49	/* The driver supports 1 passive trip point and 1 critical trip point */
	50	enum imx_thermal_trip {
	51	IMX_TRIP_PASSIVE,
	52	IMX_TRIP_CRITICAL,
	53	IMX_TRIP_NUM,
	54	};
	55
	56	/*
	57	* It defines the temperature in millicelsius for passive trip point
	58	* that will trigger cooling action when crossed.
	59	*/
	60	#define IMX_TEMP_PASSIVE 85000
	61
ca3de46b SG	62	#define IMX_POLLING_DELAY 2000 /* millisecond */
	63	#define IMX_PASSIVE_DELAY 1000
	64
749e8be7 AH	65	#define FACTOR0 10000000
	66	#define FACTOR1 15976
	67	#define FACTOR2 4297157
	68
ca3de46b SG	69	struct imx_thermal_data {
	70	struct thermal_zone_device *tz;
	71	struct thermal_cooling_device *cdev;
	72	enum thermal_device_mode mode;
	73	struct regmap *tempmon;
749e8be7	74	u32 c1, c2; /* See formula in imx_get_sensor_data() */
017e5142 PZ	75	unsigned long temp_passive;
017e5142 PZ	76	unsigned long temp_critical;
37713a1e PZ	77	unsigned long alarm_temp;
	78	unsigned long last_temp;
	79	bool irq_enabled;
	80	int irq;
329fe7b1	81	struct clk *thermal_clk;
ca3de46b SG	82	};
ca3de46b SG	83
37713a1e PZ	84	static void imx_set_alarm_temp(struct imx_thermal_data *data,
	85	signed long alarm_temp)
	86	{
	87	struct regmap *map = data->tempmon;
	88	int alarm_value;
	89
	90	data->alarm_temp = alarm_temp;
749e8be7	91	alarm_value = (data->c2 - alarm_temp) / data->c1;
37713a1e PZ	92	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
	93	regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
	94	TEMPSENSE0_ALARM_VALUE_SHIFT);
	95	}
	96
ca3de46b SG	97	static int imx_get_temp(struct thermal_zone_device tz, unsigned long temp)
	98	{
	99	struct imx_thermal_data *data = tz->devdata;
	100	struct regmap *map = data->tempmon;
ca3de46b	101	unsigned int n_meas;
37713a1e	102	bool wait;
ca3de46b SG	103	u32 val;
ca3de46b SG	104
37713a1e PZ	105	if (data->mode == THERMAL_DEVICE_ENABLED) {
	106	/* Check if a measurement is currently in progress */
	107	regmap_read(map, TEMPSENSE0, &val);
	108	wait = !(val & TEMPSENSE0_FINISHED);
	109	} else {
	110	/*
	111	* Every time we measure the temperature, we will power on the
	112	* temperature sensor, enable measurements, take a reading,
	113	* disable measurements, power off the temperature sensor.
	114	*/
	115	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	116	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
	117
	118	wait = true;
	119	}
ca3de46b SG	120
	121	/*
	122	* According to the temp sensor designers, it may require up to ~17us
	123	* to complete a measurement.
	124	*/
37713a1e PZ	125	if (wait)
37713a1e PZ	126	usleep_range(20, 50);
ca3de46b SG	127
ca3de46b SG	128	regmap_read(map, TEMPSENSE0, &val);
37713a1e PZ	129
	130	if (data->mode != THERMAL_DEVICE_ENABLED) {
	131	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	132	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	133	}
ca3de46b SG	134
	135	if ((val & TEMPSENSE0_FINISHED) == 0) {
	136	dev_dbg(&tz->device, "temp measurement never finished\n");
	137	return -EAGAIN;
	138	}
	139
	140	n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
	141
	142	/* See imx_get_sensor_data() for formula derivation */
749e8be7	143	temp = data->c2 - n_meas data->c1;
ca3de46b	144
37713a1e PZ	145	/* Update alarm value to next higher trip point */
	146	if (data->alarm_temp == data->temp_passive && *temp >= data->temp_passive)
	147	imx_set_alarm_temp(data, data->temp_critical);
	148	if (data->alarm_temp == data->temp_critical && *temp < data->temp_passive) {
	149	imx_set_alarm_temp(data, data->temp_passive);
	150	dev_dbg(&tz->device, "thermal alarm off: T < %lu\n",
	151	data->alarm_temp / 1000);
	152	}
	153
	154	if (*temp != data->last_temp) {
ca3de46b	155	dev_dbg(&tz->device, "millicelsius: %ld\n", *temp);
37713a1e PZ	156	data->last_temp = *temp;
	157	}
	158
	159	/* Reenable alarm IRQ if temperature below alarm temperature */
	160	if (!data->irq_enabled && *temp < data->alarm_temp) {
	161	data->irq_enabled = true;
	162	enable_irq(data->irq);
ca3de46b SG	163	}
	164
	165	return 0;
	166	}
	167
	168	static int imx_get_mode(struct thermal_zone_device *tz,
	169	enum thermal_device_mode *mode)
	170	{
	171	struct imx_thermal_data *data = tz->devdata;
	172
	173	*mode = data->mode;
	174
	175	return 0;
	176	}
	177
	178	static int imx_set_mode(struct thermal_zone_device *tz,
	179	enum thermal_device_mode mode)
	180	{
	181	struct imx_thermal_data *data = tz->devdata;
37713a1e	182	struct regmap *map = data->tempmon;
ca3de46b SG	183
	184	if (mode == THERMAL_DEVICE_ENABLED) {
	185	tz->polling_delay = IMX_POLLING_DELAY;
	186	tz->passive_delay = IMX_PASSIVE_DELAY;
37713a1e PZ	187
	188	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	189	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
	190
	191	if (!data->irq_enabled) {
	192	data->irq_enabled = true;
	193	enable_irq(data->irq);
	194	}
ca3de46b	195	} else {
37713a1e PZ	196	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	197	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	198
ca3de46b SG	199	tz->polling_delay = 0;
ca3de46b SG	200	tz->passive_delay = 0;
37713a1e PZ	201
	202	if (data->irq_enabled) {
	203	disable_irq(data->irq);
	204	data->irq_enabled = false;
	205	}
ca3de46b SG	206	}
	207
	208	data->mode = mode;
	209	thermal_zone_device_update(tz);
	210
	211	return 0;
	212	}
	213
	214	static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
	215	enum thermal_trip_type *type)
	216	{
	217	*type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
	218	THERMAL_TRIP_CRITICAL;
	219	return 0;
	220	}
	221
	222	static int imx_get_crit_temp(struct thermal_zone_device *tz,
	223	unsigned long *temp)
	224	{
017e5142 PZ	225	struct imx_thermal_data *data = tz->devdata;
	226
	227	*temp = data->temp_critical;
ca3de46b SG	228	return 0;
	229	}
	230
	231	static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
	232	unsigned long *temp)
	233	{
017e5142 PZ	234	struct imx_thermal_data *data = tz->devdata;
	235
	236	*temp = (trip == IMX_TRIP_PASSIVE) ? data->temp_passive :
	237	data->temp_critical;
	238	return 0;
	239	}
	240
	241	static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
	242	unsigned long temp)
	243	{
	244	struct imx_thermal_data *data = tz->devdata;
	245
	246	if (trip == IMX_TRIP_CRITICAL)
	247	return -EPERM;
	248
	249	if (temp > IMX_TEMP_PASSIVE)
	250	return -EINVAL;
	251
	252	data->temp_passive = temp;
	253
37713a1e PZ	254	imx_set_alarm_temp(data, temp);
37713a1e PZ	255
ca3de46b SG	256	return 0;
	257	}
	258
	259	static int imx_bind(struct thermal_zone_device *tz,
	260	struct thermal_cooling_device *cdev)
	261	{
	262	int ret;
	263
	264	ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
	265	THERMAL_NO_LIMIT,
	266	THERMAL_NO_LIMIT);
	267	if (ret) {
	268	dev_err(&tz->device,
	269	"binding zone %s with cdev %s failed:%d\n",
	270	tz->type, cdev->type, ret);
	271	return ret;
	272	}
	273
	274	return 0;
	275	}
	276
	277	static int imx_unbind(struct thermal_zone_device *tz,
	278	struct thermal_cooling_device *cdev)
	279	{
	280	int ret;
	281
	282	ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
	283	if (ret) {
	284	dev_err(&tz->device,
	285	"unbinding zone %s with cdev %s failed:%d\n",
	286	tz->type, cdev->type, ret);
	287	return ret;
	288	}
	289
	290	return 0;
	291	}
	292
cbb07bb3	293	static struct thermal_zone_device_ops imx_tz_ops = {
ca3de46b SG	294	.bind = imx_bind,
	295	.unbind = imx_unbind,
	296	.get_temp = imx_get_temp,
	297	.get_mode = imx_get_mode,
	298	.set_mode = imx_set_mode,
	299	.get_trip_type = imx_get_trip_type,
	300	.get_trip_temp = imx_get_trip_temp,
	301	.get_crit_temp = imx_get_crit_temp,
017e5142	302	.set_trip_temp = imx_set_trip_temp,
ca3de46b SG	303	};
	304
	305	static int imx_get_sensor_data(struct platform_device *pdev)
	306	{
	307	struct imx_thermal_data *data = platform_get_drvdata(pdev);
	308	struct regmap *map;
d0f9d64a	309	int t1, n1;
ca3de46b SG	310	int ret;
ca3de46b SG	311	u32 val;
749e8be7	312	u64 temp64;
ca3de46b SG	313
	314	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
	315	"fsl,tempmon-data");
	316	if (IS_ERR(map)) {
	317	ret = PTR_ERR(map);
	318	dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
	319	return ret;
	320	}
	321
	322	ret = regmap_read(map, OCOTP_ANA1, &val);
	323	if (ret) {
	324	dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
	325	return ret;
	326	}
	327
	328	if (val == 0 \|\| val == ~0) {
	329	dev_err(&pdev->dev, "invalid sensor calibration data\n");
	330	return -EINVAL;
	331	}
	332
	333	/*
	334	* Sensor data layout:
	335	* [31:20] - sensor value @ 25C
749e8be7 AH	336	* Use universal formula now and only need sensor value @ 25C
749e8be7 AH	337	* slope = 0.4297157 - (0.0015976 * 25C fuse)
ca3de46b SG	338	*/
ca3de46b SG	339	n1 = val >> 20;
ca3de46b SG	340	t1 = 25; /* t1 always 25C */
	341
	342	/*
749e8be7 AH	343	* Derived from linear interpolation:
	344	* slope = 0.4297157 - (0.0015976 * 25C fuse)
	345	* slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
	346	* (Nmeas - n1) / (Tmeas - t1) = slope
ca3de46b SG	347	* We want to reduce this down to the minimum computation necessary
	348	* for each temperature read. Also, we want Tmeas in millicelsius
	349	* and we don't want to lose precision from integer division. So...
749e8be7 AH	350	* Tmeas = (Nmeas - n1) / slope + t1
	351	* milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
	352	* milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
	353	* Let constant c1 = (-1000 / slope)
	354	* milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
	355	* Let constant c2 = n1 c1 + 1000 t1
	356	* milli_Tmeas = c2 - Nmeas * c1
ca3de46b	357	*/
749e8be7 AH	358	temp64 = FACTOR0;
	359	temp64 *= 1000;
	360	do_div(temp64, FACTOR1 * n1 - FACTOR2);
	361	data->c1 = temp64;
	362	data->c2 = n1 * data->c1 + 1000 * t1;
ca3de46b	363
017e5142	364	/*
d0f9d64a AH	365	* Set the default passive cooling trip point,
d0f9d64a AH	366	* can be changed from userspace.
017e5142	367	*/
d0f9d64a	368	data->temp_passive = IMX_TEMP_PASSIVE;
017e5142 PZ	369
017e5142 PZ	370	/*
d0f9d64a AH	371	* The maximum die temperature set to 20 C higher than
d0f9d64a AH	372	* IMX_TEMP_PASSIVE.
017e5142	373	*/
d0f9d64a	374	data->temp_critical = 1000 * 20 + data->temp_passive;
017e5142	375
ca3de46b SG	376	return 0;
	377	}
	378
37713a1e PZ	379	static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
	380	{
	381	struct imx_thermal_data *data = dev;
	382
	383	disable_irq_nosync(irq);
	384	data->irq_enabled = false;
	385
	386	return IRQ_WAKE_THREAD;
	387	}
	388
	389	static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
	390	{
	391	struct imx_thermal_data *data = dev;
	392
	393	dev_dbg(&data->tz->device, "THERMAL ALARM: T > %lu\n",
	394	data->alarm_temp / 1000);
	395
	396	thermal_zone_device_update(data->tz);
	397
	398	return IRQ_HANDLED;
	399	}
	400
ca3de46b SG	401	static int imx_thermal_probe(struct platform_device *pdev)
	402	{
	403	struct imx_thermal_data *data;
	404	struct cpumask clip_cpus;
	405	struct regmap *map;
37713a1e	406	int measure_freq;
ca3de46b SG	407	int ret;
	408
	409	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	410	if (!data)
	411	return -ENOMEM;
	412
	413	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
	414	if (IS_ERR(map)) {
	415	ret = PTR_ERR(map);
	416	dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
	417	return ret;
	418	}
	419	data->tempmon = map;
	420
37713a1e PZ	421	data->irq = platform_get_irq(pdev, 0);
	422	if (data->irq < 0)
	423	return data->irq;
	424
	425	ret = devm_request_threaded_irq(&pdev->dev, data->irq,
	426	imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
	427	0, "imx_thermal", data);
	428	if (ret < 0) {
	429	dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
	430	return ret;
	431	}
	432
ca3de46b SG	433	platform_set_drvdata(pdev, data);
	434
	435	ret = imx_get_sensor_data(pdev);
	436	if (ret) {
	437	dev_err(&pdev->dev, "failed to get sensor data\n");
	438	return ret;
	439	}
	440
	441	/* Make sure sensor is in known good state for measurements */
	442	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	443	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	444	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
	445	regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
	446	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	447
	448	cpumask_set_cpu(0, &clip_cpus);
	449	data->cdev = cpufreq_cooling_register(&clip_cpus);
	450	if (IS_ERR(data->cdev)) {
	451	ret = PTR_ERR(data->cdev);
	452	dev_err(&pdev->dev,
	453	"failed to register cpufreq cooling device: %d\n", ret);
	454	return ret;
	455	}
	456
	457	data->tz = thermal_zone_device_register("imx_thermal_zone",
017e5142 PZ	458	IMX_TRIP_NUM,
017e5142 PZ	459	BIT(IMX_TRIP_PASSIVE), data,
ca3de46b SG	460	&imx_tz_ops, NULL,
	461	IMX_PASSIVE_DELAY,
	462	IMX_POLLING_DELAY);
	463	if (IS_ERR(data->tz)) {
	464	ret = PTR_ERR(data->tz);
	465	dev_err(&pdev->dev,
	466	"failed to register thermal zone device %d\n", ret);
	467	cpufreq_cooling_unregister(data->cdev);
	468	return ret;
	469	}
	470
329fe7b1 AH	471	data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
	472	if (IS_ERR(data->thermal_clk)) {
	473	dev_warn(&pdev->dev, "failed to get thermal clk!\n");
	474	} else {
	475	/*
	476	* Thermal sensor needs clk on to get correct value, normally
	477	* we should enable its clk before taking measurement and disable
	478	* clk after measurement is done, but if alarm function is enabled,
	479	* hardware will auto measure the temperature periodically, so we
	480	* need to keep the clk always on for alarm function.
	481	*/
	482	ret = clk_prepare_enable(data->thermal_clk);
	483	if (ret)
	484	dev_warn(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
	485	}
	486
37713a1e PZ	487	/* Enable measurements at ~ 10 Hz */
	488	regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
	489	measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
	490	regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
	491	imx_set_alarm_temp(data, data->temp_passive);
	492	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	493	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
	494
	495	data->irq_enabled = true;
ca3de46b SG	496	data->mode = THERMAL_DEVICE_ENABLED;
	497
	498	return 0;
	499	}
	500
	501	static int imx_thermal_remove(struct platform_device *pdev)
	502	{
	503	struct imx_thermal_data *data = platform_get_drvdata(pdev);
37713a1e PZ	504	struct regmap *map = data->tempmon;
	505
	506	/* Disable measurements */
	507	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
329fe7b1 AH	508	if (!IS_ERR(data->thermal_clk))
329fe7b1 AH	509	clk_disable_unprepare(data->thermal_clk);
ca3de46b SG	510
	511	thermal_zone_device_unregister(data->tz);
	512	cpufreq_cooling_unregister(data->cdev);
	513
	514	return 0;
	515	}
	516
	517	#ifdef CONFIG_PM_SLEEP
	518	static int imx_thermal_suspend(struct device *dev)
	519	{
	520	struct imx_thermal_data *data = dev_get_drvdata(dev);
	521	struct regmap *map = data->tempmon;
ca3de46b	522
b46cce59 AH	523	/*
	524	* Need to disable thermal sensor, otherwise, when thermal core
	525	* try to get temperature before thermal sensor resume, a wrong
	526	* temperature will be read as the thermal sensor is powered
	527	* down.
	528	*/
	529	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
	530	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
	531	data->mode = THERMAL_DEVICE_DISABLED;
ca3de46b SG	532
	533	return 0;
	534	}
	535
	536	static int imx_thermal_resume(struct device *dev)
	537	{
b46cce59 AH	538	struct imx_thermal_data *data = dev_get_drvdata(dev);
	539	struct regmap *map = data->tempmon;
	540
	541	/* Enabled thermal sensor after resume */
	542	regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
	543	regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
	544	data->mode = THERMAL_DEVICE_ENABLED;
	545
ca3de46b SG	546	return 0;
	547	}
	548	#endif
	549
	550	static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
	551	imx_thermal_suspend, imx_thermal_resume);
	552
	553	static const struct of_device_id of_imx_thermal_match[] = {
	554	{ .compatible = "fsl,imx6q-tempmon", },
	555	{ /* end */ }
	556	};
dd268632	557	MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
ca3de46b SG	558
	559	static struct platform_driver imx_thermal = {
	560	.driver = {
	561	.name = "imx_thermal",
	562	.owner = THIS_MODULE,
	563	.pm = &imx_thermal_pm_ops,
	564	.of_match_table = of_imx_thermal_match,
	565	},
	566	.probe = imx_thermal_probe,
	567	.remove = imx_thermal_remove,
	568	};
	569	module_platform_driver(imx_thermal);
	570
	571	MODULE_AUTHOR("Freescale Semiconductor, Inc.");
	572	MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
	573	MODULE_LICENSE("GPL v2");
	574	MODULE_ALIAS("platform:imx-thermal");