drivers/thermal/rzg2l_thermal.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Renesas RZ/G2L TSU Thermal Sensor Driver
  *
  * Copyright (C) 2021 Renesas Electronics Corporation
  */
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/math.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
 #include <linux/thermal.h>
 #include <linux/units.h>

 #include "thermal_hwmon.h"

 #define CTEMP_MASK	0xFFF

 /* default calibration values, if FUSE values are missing */
 #define SW_CALIB0_VAL	3148
 #define SW_CALIB1_VAL	503

 /* Register offsets */
 #define TSU_SM		0x00
 #define TSU_ST		0x04
 #define TSU_SAD		0x0C
 #define TSU_SS		0x10

 #define OTPTSUTRIM_REG(n)	(0x18 + ((n) * 0x4))
 #define OTPTSUTRIM_EN_MASK	BIT(31)
 #define OTPTSUTRIM_MASK		GENMASK(11, 0)

 /* Sensor Mode Register(TSU_SM) */
 #define TSU_SM_EN_TS		BIT(0)
 #define TSU_SM_ADC_EN_TS	BIT(1)
 #define TSU_SM_NORMAL_MODE	(TSU_SM_EN_TS | TSU_SM_ADC_EN_TS)

 /* TSU_ST bits */
 #define TSU_ST_START		BIT(0)

 #define TSU_SS_CONV_RUNNING	BIT(0)

 #define TS_CODE_AVE_SCALE(x)	((x) * 1000000)
 #define MCELSIUS(temp)		((temp) * MILLIDEGREE_PER_DEGREE)
 #define TS_CODE_CAP_TIMES	8	/* Total number of ADC data samples */

 #define RZG2L_THERMAL_GRAN	500	/* milli Celsius */
 #define RZG2L_TSU_SS_TIMEOUT_US	1000

 #define CURVATURE_CORRECTION_CONST	13

 struct rzg2l_thermal_priv {
 	struct device *dev;
 	void __iomem *base;
 	struct thermal_zone_device *zone;
 	struct reset_control *rstc;
 	u32 calib0, calib1;
 };

 static inline u32 rzg2l_thermal_read(struct rzg2l_thermal_priv *priv, u32 reg)
 {
 	return ioread32(priv->base + reg);
 }

 static inline void rzg2l_thermal_write(struct rzg2l_thermal_priv *priv, u32 reg,
 				       u32 data)
 {
 	iowrite32(data, priv->base + reg);
 }

 static int rzg2l_thermal_get_temp(void *devdata, int *temp)
 {
 	struct rzg2l_thermal_priv *priv = devdata;
 	u32 result = 0, dsensor, ts_code_ave;
 	int val, i;

 	for (i = 0; i < TS_CODE_CAP_TIMES ; i++) {
 		/*
 		 * TSU repeats measurement at 20 microseconds intervals and
 		 * automatically updates the results of measurement. As per
 		 * the HW manual for measuring temperature we need to read 8
 		 * values consecutively and then take the average.
 		 * ts_code_ave = (ts_code[0] + ⋯ + ts_code[7]) / 8
 		 */
 		result += rzg2l_thermal_read(priv, TSU_SAD) & CTEMP_MASK;
 		usleep_range(20, 30);
 	}

 	ts_code_ave = result / TS_CODE_CAP_TIMES;

 	/*
 	 * Calculate actual sensor value by applying curvature correction formula
 	 * dsensor = ts_code_ave / (1 + ts_code_ave * 0.000013). Here we are doing
 	 * integer calculation by scaling all the values by 1000000.
 	 */
 	dsensor = TS_CODE_AVE_SCALE(ts_code_ave) /
 		(TS_CODE_AVE_SCALE(1) + (ts_code_ave * CURVATURE_CORRECTION_CONST));

 	/*
 	 * The temperature Tj is calculated by the formula
 	 * Tj = (dsensor − calib1) * 165/ (calib0 − calib1) − 40
 	 * where calib0 and calib1 are the calibration values.
 	 */
 	val = ((dsensor - priv->calib1) * (MCELSIUS(165) /
 		(priv->calib0 - priv->calib1))) - MCELSIUS(40);

 	*temp = roundup(val, RZG2L_THERMAL_GRAN);

 	return 0;
 }

 static const struct thermal_zone_of_device_ops rzg2l_tz_of_ops = {
 	.get_temp = rzg2l_thermal_get_temp,
 };

 static int rzg2l_thermal_init(struct rzg2l_thermal_priv *priv)
 {
 	u32 reg_val;

 	rzg2l_thermal_write(priv, TSU_SM, TSU_SM_NORMAL_MODE);
 	rzg2l_thermal_write(priv, TSU_ST, 0);

 	/*
 	 * Before setting the START bit, TSU should be in normal operating
 	 * mode. As per the HW manual, it will take 60 µs to place the TSU
 	 * into normal operating mode.
 	 */
 	usleep_range(60, 80);

 	reg_val = rzg2l_thermal_read(priv, TSU_ST);
 	reg_val |= TSU_ST_START;
 	rzg2l_thermal_write(priv, TSU_ST, reg_val);

 	return readl_poll_timeout(priv->base + TSU_SS, reg_val,
 				  reg_val == TSU_SS_CONV_RUNNING, 50,
 				  RZG2L_TSU_SS_TIMEOUT_US);
 }

 static void rzg2l_thermal_reset_assert_pm_disable_put(struct platform_device *pdev)
 {
 	struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);

 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	reset_control_assert(priv->rstc);
 }

 static int rzg2l_thermal_remove(struct platform_device *pdev)
 {
 	struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);

 	thermal_remove_hwmon_sysfs(priv->zone);
 	rzg2l_thermal_reset_assert_pm_disable_put(pdev);

 	return 0;
 }

 static int rzg2l_thermal_probe(struct platform_device *pdev)
 {
 	struct thermal_zone_device *zone;
 	struct rzg2l_thermal_priv *priv;
 	struct device *dev = &pdev->dev;
 	int ret;

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

 	priv->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->base))
 		return PTR_ERR(priv->base);

 	priv->dev = dev;
 	priv->rstc = devm_reset_control_get_exclusive(dev, NULL);
 	if (IS_ERR(priv->rstc))
 		return dev_err_probe(dev, PTR_ERR(priv->rstc),
 				     "failed to get cpg reset");

 	ret = reset_control_deassert(priv->rstc);
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to deassert");

 	pm_runtime_enable(dev);
 	pm_runtime_get_sync(dev);

 	priv->calib0 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0));
 	if (priv->calib0 & OTPTSUTRIM_EN_MASK)
 		priv->calib0 &= OTPTSUTRIM_MASK;
 	else
 		priv->calib0 = SW_CALIB0_VAL;

 	priv->calib1 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(1));
 	if (priv->calib1 & OTPTSUTRIM_EN_MASK)
 		priv->calib1 &= OTPTSUTRIM_MASK;
 	else
 		priv->calib1 = SW_CALIB1_VAL;

 	platform_set_drvdata(pdev, priv);
 	ret = rzg2l_thermal_init(priv);
 	if (ret) {
 		dev_err(dev, "Failed to start TSU");
 		goto err;
 	}

 	zone = devm_thermal_zone_of_sensor_register(dev, 0, priv,
 						    &rzg2l_tz_of_ops);
 	if (IS_ERR(zone)) {
 		dev_err(dev, "Can't register thermal zone");
 		ret = PTR_ERR(zone);
 		goto err;
 	}

 	priv->zone = zone;
 	priv->zone->tzp->no_hwmon = false;
 	ret = thermal_add_hwmon_sysfs(priv->zone);
 	if (ret)
 		goto err;

 	dev_dbg(dev, "TSU probed with %s calibration values",
 		rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0)) ?  "hw" : "sw");

 	return 0;

 err:
 	rzg2l_thermal_reset_assert_pm_disable_put(pdev);
 	return ret;
 }

 static const struct of_device_id rzg2l_thermal_dt_ids[] = {
 	{ .compatible = "renesas,rzg2l-tsu", },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rzg2l_thermal_dt_ids);

 static struct platform_driver rzg2l_thermal_driver = {
 	.driver = {
 		.name = "rzg2l_thermal",
 		.of_match_table = rzg2l_thermal_dt_ids,
 	},
 	.probe = rzg2l_thermal_probe,
 	.remove = rzg2l_thermal_remove,
 };
 module_platform_driver(rzg2l_thermal_driver);

 MODULE_DESCRIPTION("Renesas RZ/G2L TSU Thermal Sensor Driver");
 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Renesas RZ/G2L TSU Thermal Sensor Driver
	*
	* Copyright (C) 2021 Renesas Electronics Corporation
	*/
	#include <linux/delay.h>
	#include <linux/err.h>
	#include <linux/io.h>
	#include <linux/iopoll.h>
	#include <linux/math.h>
	#include <linux/module.h>
	#include <linux/of_device.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/reset.h>
	#include <linux/thermal.h>
	#include <linux/units.h>

	#include "thermal_hwmon.h"

	#define CTEMP_MASK 0xFFF

	/* default calibration values, if FUSE values are missing */
	#define SW_CALIB0_VAL 3148
	#define SW_CALIB1_VAL 503

	/* Register offsets */
	#define TSU_SM 0x00
	#define TSU_ST 0x04
	#define TSU_SAD 0x0C
	#define TSU_SS 0x10

	#define OTPTSUTRIM_REG(n) (0x18 + ((n) * 0x4))
	#define OTPTSUTRIM_EN_MASK BIT(31)
	#define OTPTSUTRIM_MASK GENMASK(11, 0)

	/* Sensor Mode Register(TSU_SM) */
	#define TSU_SM_EN_TS BIT(0)
	#define TSU_SM_ADC_EN_TS BIT(1)
	#define TSU_SM_NORMAL_MODE (TSU_SM_EN_TS \| TSU_SM_ADC_EN_TS)

	/* TSU_ST bits */
	#define TSU_ST_START BIT(0)

	#define TSU_SS_CONV_RUNNING BIT(0)

	#define TS_CODE_AVE_SCALE(x) ((x) * 1000000)
	#define MCELSIUS(temp) ((temp) * MILLIDEGREE_PER_DEGREE)
	#define TS_CODE_CAP_TIMES 8 /* Total number of ADC data samples */

	#define RZG2L_THERMAL_GRAN 500 /* milli Celsius */
	#define RZG2L_TSU_SS_TIMEOUT_US 1000

	#define CURVATURE_CORRECTION_CONST 13

	struct rzg2l_thermal_priv {
	struct device *dev;
	void __iomem *base;
	struct thermal_zone_device *zone;
	struct reset_control *rstc;
	u32 calib0, calib1;
	};

	static inline u32 rzg2l_thermal_read(struct rzg2l_thermal_priv *priv, u32 reg)
	{
	return ioread32(priv->base + reg);
	}

	static inline void rzg2l_thermal_write(struct rzg2l_thermal_priv *priv, u32 reg,
	u32 data)
	{
	iowrite32(data, priv->base + reg);
	}

	static int rzg2l_thermal_get_temp(void devdata, int temp)
	{
	struct rzg2l_thermal_priv *priv = devdata;
	u32 result = 0, dsensor, ts_code_ave;
	int val, i;

	for (i = 0; i < TS_CODE_CAP_TIMES ; i++) {
	/*
	* TSU repeats measurement at 20 microseconds intervals and
	* automatically updates the results of measurement. As per
	* the HW manual for measuring temperature we need to read 8
	* values consecutively and then take the average.
	* ts_code_ave = (ts_code[0] + ⋯ + ts_code[7]) / 8
	*/
	result += rzg2l_thermal_read(priv, TSU_SAD) & CTEMP_MASK;
	usleep_range(20, 30);
	}

	ts_code_ave = result / TS_CODE_CAP_TIMES;

	/*
	* Calculate actual sensor value by applying curvature correction formula
	* dsensor = ts_code_ave / (1 + ts_code_ave * 0.000013). Here we are doing
	* integer calculation by scaling all the values by 1000000.
	*/
	dsensor = TS_CODE_AVE_SCALE(ts_code_ave) /
	(TS_CODE_AVE_SCALE(1) + (ts_code_ave * CURVATURE_CORRECTION_CONST));

	/*
	* The temperature Tj is calculated by the formula
	* Tj = (dsensor − calib1) * 165/ (calib0 − calib1) − 40
	* where calib0 and calib1 are the calibration values.
	*/
	val = ((dsensor - priv->calib1) * (MCELSIUS(165) /
	(priv->calib0 - priv->calib1))) - MCELSIUS(40);

	*temp = roundup(val, RZG2L_THERMAL_GRAN);

	return 0;
	}

	static const struct thermal_zone_of_device_ops rzg2l_tz_of_ops = {
	.get_temp = rzg2l_thermal_get_temp,
	};

	static int rzg2l_thermal_init(struct rzg2l_thermal_priv *priv)
	{
	u32 reg_val;

	rzg2l_thermal_write(priv, TSU_SM, TSU_SM_NORMAL_MODE);
	rzg2l_thermal_write(priv, TSU_ST, 0);

	/*
	* Before setting the START bit, TSU should be in normal operating
	* mode. As per the HW manual, it will take 60 µs to place the TSU
	* into normal operating mode.
	*/
	usleep_range(60, 80);

	reg_val = rzg2l_thermal_read(priv, TSU_ST);
	reg_val \|= TSU_ST_START;
	rzg2l_thermal_write(priv, TSU_ST, reg_val);

	return readl_poll_timeout(priv->base + TSU_SS, reg_val,
	reg_val == TSU_SS_CONV_RUNNING, 50,
	RZG2L_TSU_SS_TIMEOUT_US);
	}

	static void rzg2l_thermal_reset_assert_pm_disable_put(struct platform_device *pdev)
	{
	struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);

	pm_runtime_put(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
	reset_control_assert(priv->rstc);
	}

	static int rzg2l_thermal_remove(struct platform_device *pdev)
	{
	struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);

	thermal_remove_hwmon_sysfs(priv->zone);
	rzg2l_thermal_reset_assert_pm_disable_put(pdev);

	return 0;
	}

	static int rzg2l_thermal_probe(struct platform_device *pdev)
	{
	struct thermal_zone_device *zone;
	struct rzg2l_thermal_priv *priv;
	struct device *dev = &pdev->dev;
	int ret;

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

	priv->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(priv->base))
	return PTR_ERR(priv->base);

	priv->dev = dev;
	priv->rstc = devm_reset_control_get_exclusive(dev, NULL);
	if (IS_ERR(priv->rstc))
	return dev_err_probe(dev, PTR_ERR(priv->rstc),
	"failed to get cpg reset");

	ret = reset_control_deassert(priv->rstc);
	if (ret)
	return dev_err_probe(dev, ret, "failed to deassert");

	pm_runtime_enable(dev);
	pm_runtime_get_sync(dev);

	priv->calib0 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0));
	if (priv->calib0 & OTPTSUTRIM_EN_MASK)
	priv->calib0 &= OTPTSUTRIM_MASK;
	else
	priv->calib0 = SW_CALIB0_VAL;

	priv->calib1 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(1));
	if (priv->calib1 & OTPTSUTRIM_EN_MASK)
	priv->calib1 &= OTPTSUTRIM_MASK;
	else
	priv->calib1 = SW_CALIB1_VAL;

	platform_set_drvdata(pdev, priv);
	ret = rzg2l_thermal_init(priv);
	if (ret) {
	dev_err(dev, "Failed to start TSU");
	goto err;
	}

	zone = devm_thermal_zone_of_sensor_register(dev, 0, priv,
	&rzg2l_tz_of_ops);
	if (IS_ERR(zone)) {
	dev_err(dev, "Can't register thermal zone");
	ret = PTR_ERR(zone);
	goto err;
	}

	priv->zone = zone;
	priv->zone->tzp->no_hwmon = false;
	ret = thermal_add_hwmon_sysfs(priv->zone);
	if (ret)
	goto err;

	dev_dbg(dev, "TSU probed with %s calibration values",
	rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0)) ? "hw" : "sw");

	return 0;

	err:
	rzg2l_thermal_reset_assert_pm_disable_put(pdev);
	return ret;
	}

	static const struct of_device_id rzg2l_thermal_dt_ids[] = {
	{ .compatible = "renesas,rzg2l-tsu", },
	{ /* sentinel */ }
	};
	MODULE_DEVICE_TABLE(of, rzg2l_thermal_dt_ids);

	static struct platform_driver rzg2l_thermal_driver = {
	.driver = {
	.name = "rzg2l_thermal",
	.of_match_table = rzg2l_thermal_dt_ids,
	},
	.probe = rzg2l_thermal_probe,
	.remove = rzg2l_thermal_remove,
	};
	module_platform_driver(rzg2l_thermal_driver);

	MODULE_DESCRIPTION("Renesas RZ/G2L TSU Thermal Sensor Driver");
	MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
	MODULE_LICENSE("GPL v2");