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1// SPDX-License-Identifier: GPL-2.02/*3 * Renesas RZ/G2L TSU Thermal Sensor Driver4 *5 * Copyright (C) 2021 Renesas Electronics Corporation6 */7#include <linux/delay.h>8#include <linux/err.h>9#include <linux/io.h>10#include <linux/iopoll.h>11#include <linux/math.h>12#include <linux/mod_devicetable.h>13#include <linux/module.h>14#include <linux/platform_device.h>15#include <linux/pm_runtime.h>16#include <linux/reset.h>17#include <linux/thermal.h>18#include <linux/units.h>19 20#include "../thermal_hwmon.h"21 22#define CTEMP_MASK 0xFFF23 24/* default calibration values, if FUSE values are missing */25#define SW_CALIB0_VAL 314826#define SW_CALIB1_VAL 50327 28/* Register offsets */29#define TSU_SM 0x0030#define TSU_ST 0x0431#define TSU_SAD 0x0C32#define TSU_SS 0x1033 34#define OTPTSUTRIM_REG(n) (0x18 + ((n) * 0x4))35#define OTPTSUTRIM_EN_MASK BIT(31)36#define OTPTSUTRIM_MASK GENMASK(11, 0)37 38/* Sensor Mode Register(TSU_SM) */39#define TSU_SM_EN_TS BIT(0)40#define TSU_SM_ADC_EN_TS BIT(1)41#define TSU_SM_NORMAL_MODE (TSU_SM_EN_TS | TSU_SM_ADC_EN_TS)42 43/* TSU_ST bits */44#define TSU_ST_START BIT(0)45 46#define TSU_SS_CONV_RUNNING BIT(0)47 48#define TS_CODE_AVE_SCALE(x) ((x) * 1000000)49#define MCELSIUS(temp) ((temp) * MILLIDEGREE_PER_DEGREE)50#define TS_CODE_CAP_TIMES 8 /* Total number of ADC data samples */51 52#define RZG2L_THERMAL_GRAN 500 /* milli Celsius */53#define RZG2L_TSU_SS_TIMEOUT_US 100054 55#define CURVATURE_CORRECTION_CONST 1356 57struct rzg2l_thermal_priv {58 struct device *dev;59 void __iomem *base;60 struct thermal_zone_device *zone;61 struct reset_control *rstc;62 u32 calib0, calib1;63};64 65static inline u32 rzg2l_thermal_read(struct rzg2l_thermal_priv *priv, u32 reg)66{67 return ioread32(priv->base + reg);68}69 70static inline void rzg2l_thermal_write(struct rzg2l_thermal_priv *priv, u32 reg,71 u32 data)72{73 iowrite32(data, priv->base + reg);74}75 76static int rzg2l_thermal_get_temp(struct thermal_zone_device *tz, int *temp)77{78 struct rzg2l_thermal_priv *priv = thermal_zone_device_priv(tz);79 u32 result = 0, dsensor, ts_code_ave;80 int val, i;81 82 for (i = 0; i < TS_CODE_CAP_TIMES ; i++) {83 /*84 * TSU repeats measurement at 20 microseconds intervals and85 * automatically updates the results of measurement. As per86 * the HW manual for measuring temperature we need to read 887 * values consecutively and then take the average.88 * ts_code_ave = (ts_code[0] + ⋯ + ts_code[7]) / 889 */90 result += rzg2l_thermal_read(priv, TSU_SAD) & CTEMP_MASK;91 usleep_range(20, 30);92 }93 94 ts_code_ave = result / TS_CODE_CAP_TIMES;95 96 /*97 * Calculate actual sensor value by applying curvature correction formula98 * dsensor = ts_code_ave / (1 + ts_code_ave * 0.000013). Here we are doing99 * integer calculation by scaling all the values by 1000000.100 */101 dsensor = TS_CODE_AVE_SCALE(ts_code_ave) /102 (TS_CODE_AVE_SCALE(1) + (ts_code_ave * CURVATURE_CORRECTION_CONST));103 104 /*105 * The temperature Tj is calculated by the formula106 * Tj = (dsensor − calib1) * 165/ (calib0 − calib1) − 40107 * where calib0 and calib1 are the calibration values.108 */109 val = ((dsensor - priv->calib1) * (MCELSIUS(165) /110 (priv->calib0 - priv->calib1))) - MCELSIUS(40);111 112 *temp = roundup(val, RZG2L_THERMAL_GRAN);113 114 return 0;115}116 117static const struct thermal_zone_device_ops rzg2l_tz_of_ops = {118 .get_temp = rzg2l_thermal_get_temp,119};120 121static int rzg2l_thermal_init(struct rzg2l_thermal_priv *priv)122{123 u32 reg_val;124 125 rzg2l_thermal_write(priv, TSU_SM, TSU_SM_NORMAL_MODE);126 rzg2l_thermal_write(priv, TSU_ST, 0);127 128 /*129 * Before setting the START bit, TSU should be in normal operating130 * mode. As per the HW manual, it will take 60 µs to place the TSU131 * into normal operating mode.132 */133 usleep_range(60, 80);134 135 reg_val = rzg2l_thermal_read(priv, TSU_ST);136 reg_val |= TSU_ST_START;137 rzg2l_thermal_write(priv, TSU_ST, reg_val);138 139 return readl_poll_timeout(priv->base + TSU_SS, reg_val,140 reg_val == TSU_SS_CONV_RUNNING, 50,141 RZG2L_TSU_SS_TIMEOUT_US);142}143 144static void rzg2l_thermal_reset_assert_pm_disable_put(struct platform_device *pdev)145{146 struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);147 148 pm_runtime_put(&pdev->dev);149 pm_runtime_disable(&pdev->dev);150 reset_control_assert(priv->rstc);151}152 153static void rzg2l_thermal_remove(struct platform_device *pdev)154{155 struct rzg2l_thermal_priv *priv = dev_get_drvdata(&pdev->dev);156 157 thermal_remove_hwmon_sysfs(priv->zone);158 rzg2l_thermal_reset_assert_pm_disable_put(pdev);159}160 161static int rzg2l_thermal_probe(struct platform_device *pdev)162{163 struct thermal_zone_device *zone;164 struct rzg2l_thermal_priv *priv;165 struct device *dev = &pdev->dev;166 int ret;167 168 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);169 if (!priv)170 return -ENOMEM;171 172 priv->base = devm_platform_ioremap_resource(pdev, 0);173 if (IS_ERR(priv->base))174 return PTR_ERR(priv->base);175 176 priv->dev = dev;177 priv->rstc = devm_reset_control_get_exclusive(dev, NULL);178 if (IS_ERR(priv->rstc))179 return dev_err_probe(dev, PTR_ERR(priv->rstc),180 "failed to get cpg reset");181 182 ret = reset_control_deassert(priv->rstc);183 if (ret)184 return dev_err_probe(dev, ret, "failed to deassert");185 186 pm_runtime_enable(dev);187 pm_runtime_get_sync(dev);188 189 priv->calib0 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0));190 if (priv->calib0 & OTPTSUTRIM_EN_MASK)191 priv->calib0 &= OTPTSUTRIM_MASK;192 else193 priv->calib0 = SW_CALIB0_VAL;194 195 priv->calib1 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(1));196 if (priv->calib1 & OTPTSUTRIM_EN_MASK)197 priv->calib1 &= OTPTSUTRIM_MASK;198 else199 priv->calib1 = SW_CALIB1_VAL;200 201 platform_set_drvdata(pdev, priv);202 ret = rzg2l_thermal_init(priv);203 if (ret) {204 dev_err(dev, "Failed to start TSU");205 goto err;206 }207 208 zone = devm_thermal_of_zone_register(dev, 0, priv,209 &rzg2l_tz_of_ops);210 if (IS_ERR(zone)) {211 dev_err(dev, "Can't register thermal zone");212 ret = PTR_ERR(zone);213 goto err;214 }215 216 priv->zone = zone;217 ret = thermal_add_hwmon_sysfs(priv->zone);218 if (ret)219 goto err;220 221 dev_dbg(dev, "TSU probed with %s calibration values",222 rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0)) ? "hw" : "sw");223 224 return 0;225 226err:227 rzg2l_thermal_reset_assert_pm_disable_put(pdev);228 return ret;229}230 231static const struct of_device_id rzg2l_thermal_dt_ids[] = {232 { .compatible = "renesas,rzg2l-tsu", },233 { /* sentinel */ }234};235MODULE_DEVICE_TABLE(of, rzg2l_thermal_dt_ids);236 237static struct platform_driver rzg2l_thermal_driver = {238 .driver = {239 .name = "rzg2l_thermal",240 .of_match_table = rzg2l_thermal_dt_ids,241 },242 .probe = rzg2l_thermal_probe,243 .remove_new = rzg2l_thermal_remove,244};245module_platform_driver(rzg2l_thermal_driver);246 247MODULE_DESCRIPTION("Renesas RZ/G2L TSU Thermal Sensor Driver");248MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");249MODULE_LICENSE("GPL v2");250