[linux-2.6-block.git] / drivers / thermal / db8500_thermal.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * db8500_thermal.c - DB8500 Thermal Management Implementation
 *
 * Copyright (C) 2012 ST-Ericsson
 * Copyright (C) 2012-2019 Linaro Ltd.
 *
 * Authors: Hongbo Zhang, Linus Walleij
 */

#include <linux/cpu_cooling.h>
#include <linux/interrupt.h>
#include <linux/mfd/dbx500-prcmu.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/thermal.h>

#define PRCMU_DEFAULT_MEASURE_TIME	0xFFF
#define PRCMU_DEFAULT_LOW_TEMP		0

/**
 * db8500_thermal_points - the interpolation points that trigger
 * interrupts
 */
static const unsigned long db8500_thermal_points[] = {
	15000,
	20000,
	25000,
	30000,
	35000,
	40000,
	45000,
	50000,
	55000,
	60000,
	65000,
	70000,
	75000,
	80000,
	/*
	 * This is where things start to get really bad for the
	 * SoC and the thermal zones should be set up to trigger
	 * critical temperature at 85000 mC so we don't get above
	 * this point.
	 */
	85000,
	90000,
	95000,
	100000,
};

struct db8500_thermal_zone {
	struct thermal_zone_device *tz;
	enum thermal_trend trend;
	unsigned long interpolated_temp;
	unsigned int cur_index;
};

/* Callback to get current temperature */
static int db8500_thermal_get_temp(void *data, int *temp)
{
	struct db8500_thermal_zone *th = data;

	/*
	 * TODO: There is no PRCMU interface to get temperature data currently,
	 * so a pseudo temperature is returned , it works for thermal framework
	 * and this will be fixed when the PRCMU interface is available.
	 */
	*temp = th->interpolated_temp;

	return 0;
}

/* Callback to get temperature changing trend */
static int db8500_thermal_get_trend(void *data, int trip, enum thermal_trend *trend)
{
	struct db8500_thermal_zone *th = data;

	*trend = th->trend;

	return 0;
}

static struct thermal_zone_of_device_ops thdev_ops = {
	.get_temp = db8500_thermal_get_temp,
	.get_trend = db8500_thermal_get_trend,
};

static void db8500_thermal_update_config(struct db8500_thermal_zone *th,
					 unsigned int idx,
					 enum thermal_trend trend,
					 unsigned long next_low,
					 unsigned long next_high)
{
	prcmu_stop_temp_sense();

	th->cur_index = idx;
	th->interpolated_temp = (next_low + next_high)/2;
	th->trend = trend;

	/*
	 * The PRCMU accept absolute temperatures in celsius so divide
	 * down the millicelsius with 1000
	 */
	prcmu_config_hotmon((u8)(next_low/1000), (u8)(next_high/1000));
	prcmu_start_temp_sense(PRCMU_DEFAULT_MEASURE_TIME);
}

static irqreturn_t prcmu_low_irq_handler(int irq, void *irq_data)
{
	struct db8500_thermal_zone *th = irq_data;
	unsigned int idx = th->cur_index;
	unsigned long next_low, next_high;

	if (idx == 0)
		/* Meaningless for thermal management, ignoring it */
		return IRQ_HANDLED;

	if (idx == 1) {
		next_high = db8500_thermal_points[0];
		next_low = PRCMU_DEFAULT_LOW_TEMP;
	} else {
		next_high = db8500_thermal_points[idx - 1];
		next_low = db8500_thermal_points[idx - 2];
	}
	idx -= 1;

	db8500_thermal_update_config(th, idx, THERMAL_TREND_DROPPING,
				     next_low, next_high);
	dev_dbg(&th->tz->device,
		"PRCMU set max %ld, min %ld\n", next_high, next_low);

	thermal_zone_device_update(th->tz, THERMAL_EVENT_UNSPECIFIED);

	return IRQ_HANDLED;
}

static irqreturn_t prcmu_high_irq_handler(int irq, void *irq_data)
{
	struct db8500_thermal_zone *th = irq_data;
	unsigned int idx = th->cur_index;
	unsigned long next_low, next_high;
	int num_points = ARRAY_SIZE(db8500_thermal_points);

	if (idx < num_points - 1) {
		next_high = db8500_thermal_points[idx+1];
		next_low = db8500_thermal_points[idx];
		idx += 1;

		db8500_thermal_update_config(th, idx, THERMAL_TREND_RAISING,
					     next_low, next_high);

		dev_dbg(&th->tz->device,
			"PRCMU set max %ld, min %ld\n", next_high, next_low);
	} else if (idx == num_points - 1)
		/* So we roof out 1 degree over the max point */
		th->interpolated_temp = db8500_thermal_points[idx] + 1;

	thermal_zone_device_update(th->tz, THERMAL_EVENT_UNSPECIFIED);

	return IRQ_HANDLED;
}

static int db8500_thermal_probe(struct platform_device *pdev)
{
	struct db8500_thermal_zone *th = NULL;
	struct device *dev = &pdev->dev;
	int low_irq, high_irq, ret = 0;

	th = devm_kzalloc(dev, sizeof(*th), GFP_KERNEL);
	if (!th)
		return -ENOMEM;

	low_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_LOW");
	if (low_irq < 0) {
		dev_err(dev, "Get IRQ_HOTMON_LOW failed\n");
		return low_irq;
	}

	ret = devm_request_threaded_irq(dev, low_irq, NULL,
		prcmu_low_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
		"dbx500_temp_low", th);
	if (ret < 0) {
		dev_err(dev, "failed to allocate temp low irq\n");
		return ret;
	}

	high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
	if (high_irq < 0) {
		dev_err(dev, "Get IRQ_HOTMON_HIGH failed\n");
		return high_irq;
	}

	ret = devm_request_threaded_irq(dev, high_irq, NULL,
		prcmu_high_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
		"dbx500_temp_high", th);
	if (ret < 0) {
		dev_err(dev, "failed to allocate temp high irq\n");
		return ret;
	}

	/* register of thermal sensor and get info from DT */
	th->tz = devm_thermal_zone_of_sensor_register(dev, 0, th, &thdev_ops);
	if (IS_ERR(th->tz)) {
		dev_err(dev, "register thermal zone sensor failed\n");
		return PTR_ERR(th->tz);
	}
	dev_info(dev, "thermal zone sensor registered\n");

	/* Start measuring at the lowest point */
	db8500_thermal_update_config(th, 0, THERMAL_TREND_STABLE,
				     PRCMU_DEFAULT_LOW_TEMP,
				     db8500_thermal_points[0]);

	platform_set_drvdata(pdev, th);

	return 0;
}

static int db8500_thermal_suspend(struct platform_device *pdev,
		pm_message_t state)
{
	prcmu_stop_temp_sense();

	return 0;
}

static int db8500_thermal_resume(struct platform_device *pdev)
{
	struct db8500_thermal_zone *th = platform_get_drvdata(pdev);

	/* Resume and start measuring at the lowest point */
	db8500_thermal_update_config(th, 0, THERMAL_TREND_STABLE,
				     PRCMU_DEFAULT_LOW_TEMP,
				     db8500_thermal_points[0]);

	return 0;
}

static const struct of_device_id db8500_thermal_match[] = {
	{ .compatible = "stericsson,db8500-thermal" },
	{},
};
MODULE_DEVICE_TABLE(of, db8500_thermal_match);

static struct platform_driver db8500_thermal_driver = {
	.driver = {
		.name = "db8500-thermal",
		.of_match_table = of_match_ptr(db8500_thermal_match),
	},
	.probe = db8500_thermal_probe,
	.suspend = db8500_thermal_suspend,
	.resume = db8500_thermal_resume,
};

module_platform_driver(db8500_thermal_driver);

MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
MODULE_DESCRIPTION("DB8500 thermal driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/*
	3	* db8500_thermal.c - DB8500 Thermal Management Implementation
	4	*
	5	* Copyright (C) 2012 ST-Ericsson
	6	* Copyright (C) 2012-2019 Linaro Ltd.
	7	*
	8	* Authors: Hongbo Zhang, Linus Walleij
	9	*/
	10
	11	#include <linux/cpu_cooling.h>
	12	#include <linux/interrupt.h>
	13	#include <linux/mfd/dbx500-prcmu.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/slab.h>
	18	#include <linux/thermal.h>
	19
	20	#define PRCMU_DEFAULT_MEASURE_TIME 0xFFF
	21	#define PRCMU_DEFAULT_LOW_TEMP 0
	22
	23	/**
	24	* db8500_thermal_points - the interpolation points that trigger
	25	* interrupts
	26	*/
	27	static const unsigned long db8500_thermal_points[] = {
	28	15000,
	29	20000,
	30	25000,
	31	30000,
	32	35000,
	33	40000,
	34	45000,
	35	50000,
	36	55000,
	37	60000,
	38	65000,
	39	70000,
	40	75000,
	41	80000,
	42	/*
	43	* This is where things start to get really bad for the
	44	* SoC and the thermal zones should be set up to trigger
	45	* critical temperature at 85000 mC so we don't get above
	46	* this point.
	47	*/
	48	85000,
	49	90000,
	50	95000,
	51	100000,
	52	};
	53
	54	struct db8500_thermal_zone {
	55	struct thermal_zone_device *tz;
	56	enum thermal_trend trend;
	57	unsigned long interpolated_temp;
	58	unsigned int cur_index;
	59	};
	60
	61	/* Callback to get current temperature */
	62	static int db8500_thermal_get_temp(void data, int temp)
	63	{
	64	struct db8500_thermal_zone *th = data;
	65
	66	/*
	67	* TODO: There is no PRCMU interface to get temperature data currently,
	68	* so a pseudo temperature is returned , it works for thermal framework
	69	* and this will be fixed when the PRCMU interface is available.
	70	*/
	71	*temp = th->interpolated_temp;
	72
	73	return 0;
	74	}
	75
	76	/* Callback to get temperature changing trend */
	77	static int db8500_thermal_get_trend(void data, int trip, enum thermal_trend trend)
	78	{
	79	struct db8500_thermal_zone *th = data;
	80
	81	*trend = th->trend;
	82
	83	return 0;
	84	}
	85
	86	static struct thermal_zone_of_device_ops thdev_ops = {
	87	.get_temp = db8500_thermal_get_temp,
	88	.get_trend = db8500_thermal_get_trend,
	89	};
	90
	91	static void db8500_thermal_update_config(struct db8500_thermal_zone *th,
	92	unsigned int idx,
	93	enum thermal_trend trend,
	94	unsigned long next_low,
	95	unsigned long next_high)
	96	{
	97	prcmu_stop_temp_sense();
	98
	99	th->cur_index = idx;
	100	th->interpolated_temp = (next_low + next_high)/2;
	101	th->trend = trend;
	102
	103	/*
	104	* The PRCMU accept absolute temperatures in celsius so divide
	105	* down the millicelsius with 1000
	106	*/
	107	prcmu_config_hotmon((u8)(next_low/1000), (u8)(next_high/1000));
	108	prcmu_start_temp_sense(PRCMU_DEFAULT_MEASURE_TIME);
	109	}
	110
	111	static irqreturn_t prcmu_low_irq_handler(int irq, void *irq_data)
	112	{
	113	struct db8500_thermal_zone *th = irq_data;
	114	unsigned int idx = th->cur_index;
	115	unsigned long next_low, next_high;
	116
	117	if (idx == 0)
	118	/* Meaningless for thermal management, ignoring it */
	119	return IRQ_HANDLED;
	120
	121	if (idx == 1) {
	122	next_high = db8500_thermal_points[0];
	123	next_low = PRCMU_DEFAULT_LOW_TEMP;
	124	} else {
	125	next_high = db8500_thermal_points[idx - 1];
	126	next_low = db8500_thermal_points[idx - 2];
	127	}
	128	idx -= 1;
	129
	130	db8500_thermal_update_config(th, idx, THERMAL_TREND_DROPPING,
	131	next_low, next_high);
	132	dev_dbg(&th->tz->device,
	133	"PRCMU set max %ld, min %ld\n", next_high, next_low);
	134
	135	thermal_zone_device_update(th->tz, THERMAL_EVENT_UNSPECIFIED);
	136
	137	return IRQ_HANDLED;
	138	}
	139
	140	static irqreturn_t prcmu_high_irq_handler(int irq, void *irq_data)
	141	{
	142	struct db8500_thermal_zone *th = irq_data;
	143	unsigned int idx = th->cur_index;
	144	unsigned long next_low, next_high;
	145	int num_points = ARRAY_SIZE(db8500_thermal_points);
	146
	147	if (idx < num_points - 1) {
	148	next_high = db8500_thermal_points[idx+1];
	149	next_low = db8500_thermal_points[idx];
	150	idx += 1;
	151
	152	db8500_thermal_update_config(th, idx, THERMAL_TREND_RAISING,
	153	next_low, next_high);
	154
	155	dev_dbg(&th->tz->device,
	156	"PRCMU set max %ld, min %ld\n", next_high, next_low);
	157	} else if (idx == num_points - 1)
	158	/* So we roof out 1 degree over the max point */
	159	th->interpolated_temp = db8500_thermal_points[idx] + 1;
	160
	161	thermal_zone_device_update(th->tz, THERMAL_EVENT_UNSPECIFIED);
	162
	163	return IRQ_HANDLED;
	164	}
	165
	166	static int db8500_thermal_probe(struct platform_device *pdev)
	167	{
	168	struct db8500_thermal_zone *th = NULL;
	169	struct device *dev = &pdev->dev;
	170	int low_irq, high_irq, ret = 0;
	171
	172	th = devm_kzalloc(dev, sizeof(*th), GFP_KERNEL);
	173	if (!th)
	174	return -ENOMEM;
	175
	176	low_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_LOW");
	177	if (low_irq < 0) {
	178	dev_err(dev, "Get IRQ_HOTMON_LOW failed\n");
	179	return low_irq;
	180	}
	181
	182	ret = devm_request_threaded_irq(dev, low_irq, NULL,
	183	prcmu_low_irq_handler, IRQF_NO_SUSPEND \| IRQF_ONESHOT,
	184	"dbx500_temp_low", th);
	185	if (ret < 0) {
	186	dev_err(dev, "failed to allocate temp low irq\n");
	187	return ret;
	188	}
	189
	190	high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
	191	if (high_irq < 0) {
	192	dev_err(dev, "Get IRQ_HOTMON_HIGH failed\n");
	193	return high_irq;
	194	}
	195
	196	ret = devm_request_threaded_irq(dev, high_irq, NULL,
	197	prcmu_high_irq_handler, IRQF_NO_SUSPEND \| IRQF_ONESHOT,
	198	"dbx500_temp_high", th);
	199	if (ret < 0) {
	200	dev_err(dev, "failed to allocate temp high irq\n");
	201	return ret;
	202	}
	203
	204	/* register of thermal sensor and get info from DT */
	205	th->tz = devm_thermal_zone_of_sensor_register(dev, 0, th, &thdev_ops);
	206	if (IS_ERR(th->tz)) {
	207	dev_err(dev, "register thermal zone sensor failed\n");
	208	return PTR_ERR(th->tz);
	209	}
	210	dev_info(dev, "thermal zone sensor registered\n");
	211
	212	/* Start measuring at the lowest point */
	213	db8500_thermal_update_config(th, 0, THERMAL_TREND_STABLE,
	214	PRCMU_DEFAULT_LOW_TEMP,
	215	db8500_thermal_points[0]);
	216
	217	platform_set_drvdata(pdev, th);
	218
	219	return 0;
	220	}
	221
	222	static int db8500_thermal_suspend(struct platform_device *pdev,
	223	pm_message_t state)
	224	{
	225	prcmu_stop_temp_sense();
	226
	227	return 0;
	228	}
	229
	230	static int db8500_thermal_resume(struct platform_device *pdev)
	231	{
	232	struct db8500_thermal_zone *th = platform_get_drvdata(pdev);
	233
	234	/* Resume and start measuring at the lowest point */
	235	db8500_thermal_update_config(th, 0, THERMAL_TREND_STABLE,
	236	PRCMU_DEFAULT_LOW_TEMP,
	237	db8500_thermal_points[0]);
	238
	239	return 0;
	240	}
	241
	242	static const struct of_device_id db8500_thermal_match[] = {
	243	{ .compatible = "stericsson,db8500-thermal" },
	244	{},
	245	};
	246	MODULE_DEVICE_TABLE(of, db8500_thermal_match);
	247
	248	static struct platform_driver db8500_thermal_driver = {
	249	.driver = {
	250	.name = "db8500-thermal",
	251	.of_match_table = of_match_ptr(db8500_thermal_match),
	252	},
	253	.probe = db8500_thermal_probe,
	254	.suspend = db8500_thermal_suspend,
	255	.resume = db8500_thermal_resume,
	256	};
	257
	258	module_platform_driver(db8500_thermal_driver);
	259
	260	MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
	261	MODULE_DESCRIPTION("DB8500 thermal driver");
	262	MODULE_LICENSE("GPL");