// SPDX-License-Identifier: GPL-2.0 /* * Renesas RZ/G2L TSU Thermal Sensor Driver * * Copyright (C) 2021 Renesas Electronics Corporation */ #include #include #include #include #include #include #include #include #include #include #include #include #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)) /* 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 /* Capture times */ #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 caliberation 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(&pdev->dev, NULL); if (IS_ERR(priv->rstc)) return dev_err_probe(dev, PTR_ERR(priv->rstc), "failed to get cpg reset"); reset_control_deassert(priv->rstc); pm_runtime_enable(dev); pm_runtime_get_sync(dev); priv->calib0 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(0)); if (!priv->calib0) priv->calib0 = SW_CALIB0_VAL; priv->calib1 = rzg2l_thermal_read(priv, OTPTSUTRIM_REG(1)); if (!priv->calib1) 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 caliberation 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 "); MODULE_LICENSE("GPL v2");