253 lines
6.5 KiB
C
253 lines
6.5 KiB
C
// 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");
|