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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Dove thermal sensor driver4 *5 * Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch>6 */7#include <linux/device.h>8#include <linux/err.h>9#include <linux/io.h>10#include <linux/kernel.h>11#include <linux/of.h>12#include <linux/module.h>13#include <linux/platform_device.h>14#include <linux/thermal.h>15 16#define DOVE_THERMAL_TEMP_OFFSET 117#define DOVE_THERMAL_TEMP_MASK 0x1FF18 19/* Dove Thermal Manager Control and Status Register */20#define PMU_TM_DISABLE_OFFS 021#define PMU_TM_DISABLE_MASK (0x1 << PMU_TM_DISABLE_OFFS)22 23/* Dove Theraml Diode Control 0 Register */24#define PMU_TDC0_SW_RST_MASK (0x1 << 1)25#define PMU_TDC0_SEL_VCAL_OFFS 526#define PMU_TDC0_SEL_VCAL_MASK (0x3 << PMU_TDC0_SEL_VCAL_OFFS)27#define PMU_TDC0_REF_CAL_CNT_OFFS 1128#define PMU_TDC0_REF_CAL_CNT_MASK (0x1FF << PMU_TDC0_REF_CAL_CNT_OFFS)29#define PMU_TDC0_AVG_NUM_OFFS 2530#define PMU_TDC0_AVG_NUM_MASK (0x7 << PMU_TDC0_AVG_NUM_OFFS)31 32/* Dove Thermal Diode Control 1 Register */33#define PMU_TEMP_DIOD_CTRL1_REG 0x0434#define PMU_TDC1_TEMP_VALID_MASK (0x1 << 10)35 36/* Dove Thermal Sensor Dev Structure */37struct dove_thermal_priv {38 void __iomem *sensor;39 void __iomem *control;40};41 42static int dove_init_sensor(const struct dove_thermal_priv *priv)43{44 u32 reg;45 u32 i;46 47 /* Configure the Diode Control Register #0 */48 reg = readl_relaxed(priv->control);49 50 /* Use average of 2 */51 reg &= ~PMU_TDC0_AVG_NUM_MASK;52 reg |= (0x1 << PMU_TDC0_AVG_NUM_OFFS);53 54 /* Reference calibration value */55 reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;56 reg |= (0x0F1 << PMU_TDC0_REF_CAL_CNT_OFFS);57 58 /* Set the high level reference for calibration */59 reg &= ~PMU_TDC0_SEL_VCAL_MASK;60 reg |= (0x2 << PMU_TDC0_SEL_VCAL_OFFS);61 writel(reg, priv->control);62 63 /* Reset the sensor */64 reg = readl_relaxed(priv->control);65 writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);66 writel(reg, priv->control);67 68 /* Enable the sensor */69 reg = readl_relaxed(priv->sensor);70 reg &= ~PMU_TM_DISABLE_MASK;71 writel(reg, priv->sensor);72 73 /* Poll the sensor for the first reading */74 for (i = 0; i < 1000000; i++) {75 reg = readl_relaxed(priv->sensor);76 if (reg & DOVE_THERMAL_TEMP_MASK)77 break;78 }79 80 if (i == 1000000)81 return -EIO;82 83 return 0;84}85 86static int dove_get_temp(struct thermal_zone_device *thermal,87 int *temp)88{89 unsigned long reg;90 struct dove_thermal_priv *priv = thermal_zone_device_priv(thermal);91 92 /* Valid check */93 reg = readl_relaxed(priv->control + PMU_TEMP_DIOD_CTRL1_REG);94 if ((reg & PMU_TDC1_TEMP_VALID_MASK) == 0x0)95 return -EIO;96 97 /*98 * Calculate temperature. According to Marvell internal99 * documentation the formula for this is:100 * Celsius = (322-reg)/1.3625101 */102 reg = readl_relaxed(priv->sensor);103 reg = (reg >> DOVE_THERMAL_TEMP_OFFSET) & DOVE_THERMAL_TEMP_MASK;104 *temp = ((3220000000UL - (10000000UL * reg)) / 13625);105 106 return 0;107}108 109static struct thermal_zone_device_ops ops = {110 .get_temp = dove_get_temp,111};112 113static const struct of_device_id dove_thermal_id_table[] = {114 { .compatible = "marvell,dove-thermal" },115 {}116};117 118static int dove_thermal_probe(struct platform_device *pdev)119{120 struct thermal_zone_device *thermal = NULL;121 struct dove_thermal_priv *priv;122 int ret;123 124 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);125 if (!priv)126 return -ENOMEM;127 128 priv->sensor = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);129 if (IS_ERR(priv->sensor))130 return PTR_ERR(priv->sensor);131 132 priv->control = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);133 if (IS_ERR(priv->control))134 return PTR_ERR(priv->control);135 136 ret = dove_init_sensor(priv);137 if (ret) {138 dev_err(&pdev->dev, "Failed to initialize sensor\n");139 return ret;140 }141 142 thermal = thermal_tripless_zone_device_register("dove_thermal", priv,143 &ops, NULL);144 if (IS_ERR(thermal)) {145 dev_err(&pdev->dev,146 "Failed to register thermal zone device\n");147 return PTR_ERR(thermal);148 }149 150 ret = thermal_zone_device_enable(thermal);151 if (ret) {152 thermal_zone_device_unregister(thermal);153 return ret;154 }155 156 platform_set_drvdata(pdev, thermal);157 158 return 0;159}160 161static void dove_thermal_exit(struct platform_device *pdev)162{163 struct thermal_zone_device *dove_thermal =164 platform_get_drvdata(pdev);165 166 thermal_zone_device_unregister(dove_thermal);167}168 169MODULE_DEVICE_TABLE(of, dove_thermal_id_table);170 171static struct platform_driver dove_thermal_driver = {172 .probe = dove_thermal_probe,173 .remove_new = dove_thermal_exit,174 .driver = {175 .name = "dove_thermal",176 .of_match_table = dove_thermal_id_table,177 },178};179 180module_platform_driver(dove_thermal_driver);181 182MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");183MODULE_DESCRIPTION("Dove thermal driver");184MODULE_LICENSE("GPL");185