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alistair23-linux/drivers/thermal/sun8i_thermal.c

418 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Thermal sensor driver for Allwinner SOC
* Copyright (C) 2019 Yangtao Li
*
* Based on the work of Icenowy Zheng <icenowy@aosc.io>
* Based on the work of Ondrej Jirman <megous@megous.com>
* Based on the work of Josef Gajdusek <atx@atx.name>
*/
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/nvmem-consumer.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include <linux/thermal.h>
#define MAX_SENSOR_NUM 4
#define SUN50I_H6_OFFSET -2794
#define SUN50I_H6_SCALE -67
#define FT_TEMP_MASK GENMASK(11, 0)
#define TEMP_CALIB_MASK GENMASK(11, 0)
#define TEMP_TO_REG 672
#define CALIBRATE_DEFAULT 0x800
#define SUN50I_THS_CTRL0 0x00
#define SUN50I_H6_THS_ENABLE 0x04
#define SUN50I_H6_THS_PC 0x08
#define SUN50I_H6_THS_DIC 0x10
#define SUN50I_H6_THS_DIS 0x20
#define SUN50I_H6_THS_MFC 0x30
#define SUN50I_H6_THS_TEMP_CALIB 0xa0
#define SUN50I_H6_THS_TEMP_DATA 0xc0
#define SUN50I_THS_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16)
#define SUN50I_THS_FILTER_EN BIT(2)
#define SUN50I_THS_FILTER_TYPE(x) (GENMASK(1, 0) & (x))
#define SUN50I_H6_THS_PC_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12)
#define SUN50I_H6_THS_DATA_IRQ_STS(x) BIT(x)
/* millidegree celsius */
#define SUN50I_H6_FT_DEVIATION 7000
struct ths_device;
struct tsensor {
struct ths_device *tmdev;
struct thermal_zone_device *tzd;
int id;
};
struct ths_thermal_chip {
int sensor_num;
};
struct ths_device {
const struct ths_thermal_chip *chip;
struct device *dev;
struct regmap *regmap;
struct reset_control *reset;
struct clk *bus_clk;
struct tsensor sensor[MAX_SENSOR_NUM];
};
/* Temp Unit: millidegree Celsius */
static int sun8i_ths_reg2temp(struct ths_device *tmdev,
int reg)
{
return (reg + SUN50I_H6_OFFSET) * SUN50I_H6_SCALE;
}
static int sun8i_ths_get_temp(void *data, int *temp)
{
struct tsensor *s = data;
struct ths_device *tmdev = s->tmdev;
int val;
regmap_read(tmdev->regmap, SUN50I_H6_THS_TEMP_DATA +
0x4 * s->id, &val);
/* ths have no data yet */
if (!val)
return -EBUSY;
*temp = sun8i_ths_reg2temp(tmdev, val);
/*
* XX - According to the original sdk, there are some platforms(rarely)
* that add a fixed offset value after calculating the temperature
* value. We can't simply put it on the formula for calculating the
* temperature above, because the formula for calculating the
* temperature above is also used when the sensor is calibrated. If
* do this, the correct calibration formula is hard to know.
*/
*temp += SUN50I_H6_FT_DEVIATION;
return 0;
}
static const struct thermal_zone_of_device_ops ths_ops = {
.get_temp = sun8i_ths_get_temp,
};
static const struct regmap_config config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.fast_io = true,
};
static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
{
struct ths_device *tmdev = data;
int i, state;
regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
for (i = 0; i < tmdev->chip->sensor_num; i++) {
if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
/* clear data irq pending */
regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
SUN50I_H6_THS_DATA_IRQ_STS(i));
thermal_zone_device_update(tmdev->sensor[i].tzd,
THERMAL_EVENT_UNSPECIFIED);
}
}
return IRQ_HANDLED;
}
static int sun50i_ths_calibrate(struct ths_device *tmdev)
{
struct nvmem_cell *calcell;
struct device *dev = tmdev->dev;
u16 *caldata;
size_t callen;
int ft_temp;
int i, ret = 0;
calcell = devm_nvmem_cell_get(dev, "calib");
if (IS_ERR(calcell)) {
if (PTR_ERR(calcell) == -EPROBE_DEFER)
return -EPROBE_DEFER;
/*
* Even if the external calibration data stored in sid is
* not accessible, the THS hardware can still work, although
* the data won't be so accurate.
*
* The default value of calibration register is 0x800 for
* every sensor, and the calibration value is usually 0x7xx
* or 0x8xx, so they won't be away from the default value
* for a lot.
*
* So here we do not return error if the calibartion data is
* not available, except the probe needs deferring.
*/
goto out;
}
caldata = nvmem_cell_read(calcell, &callen);
if (IS_ERR(caldata)) {
ret = PTR_ERR(caldata);
goto out;
}
if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
ret = -EINVAL;
goto out_free;
}
/*
* efuse layout:
*
* 0 11 16 32
* +-------+-------+-------+
* |temp| |sensor0|sensor1|
* +-------+-------+-------+
*
* The calibration data on the H6 is the ambient temperature and
* sensor values that are filled during the factory test stage.
*
* The unit of stored FT temperature is 0.1 degreee celusis.
* Through the stored ambient temperature and the data read
* by the sensor, after a certain calculation, the calibration
* value to be compensated can be obtained.
*/
ft_temp = caldata[0] & FT_TEMP_MASK;
for (i = 0; i < tmdev->chip->sensor_num; i++) {
int reg = (int)caldata[i + 1];
int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
int delta, cdata, calib_offest;
/*
* To calculate the calibration value:
*
* X(in Celsius) = Ts - ft_temp
* delta = X * 10000 / TEMP_TO_REG
* cdata = CALIBRATE_DEFAULT - delta
*
* cdata: calibration value
*/
delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
cdata = CALIBRATE_DEFAULT - delta;
if (cdata & ~TEMP_CALIB_MASK) {
/*
* Calibration value more than 12-bit, but calibration
* register is 12-bit. In this case, ths hardware can
* still work without calibration, although the data
* won't be so accurate.
*/
dev_warn(dev, "sensor%d is not calibrated.\n", i);
continue;
}
calib_offest = SUN50I_H6_THS_TEMP_CALIB + (i / 2) * 0x4;
if (i % 2) {
int val;
regmap_read(tmdev->regmap, calib_offest, &val);
val = (val & TEMP_CALIB_MASK) | (cdata << 16);
regmap_write(tmdev->regmap, calib_offest, val);
} else {
regmap_write(tmdev->regmap, calib_offest, cdata);
}
}
out_free:
kfree(caldata);
out:
return ret;
}
static int sun8i_ths_resource_init(struct ths_device *tmdev)
{
struct device *dev = tmdev->dev;
struct platform_device *pdev = to_platform_device(dev);
struct resource *mem;
void __iomem *base;
int ret;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(dev, mem);
if (IS_ERR(base))
return PTR_ERR(base);
tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
if (IS_ERR(tmdev->regmap))
return PTR_ERR(tmdev->regmap);
tmdev->reset = devm_reset_control_get(dev, 0);
if (IS_ERR(tmdev->reset))
return PTR_ERR(tmdev->reset);
tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
if (IS_ERR(tmdev->bus_clk))
return PTR_ERR(tmdev->bus_clk);
ret = reset_control_deassert(tmdev->reset);
if (ret)
return ret;
ret = clk_prepare_enable(tmdev->bus_clk);
if (ret)
goto assert_reset;
ret = sun50i_ths_calibrate(tmdev);
if (ret)
goto bus_disable;
return 0;
bus_disable:
clk_disable_unprepare(tmdev->bus_clk);
assert_reset:
reset_control_assert(tmdev->reset);
return ret;
}
static int sun50i_thermal_init(struct ths_device *tmdev)
{
int val;
/*
* clkin = 24MHz
* T acquire = clkin / (x + 1)
* = 20us
*/
regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
SUN50I_THS_CTRL0_T_ACQ(479));
/* average over 4 samples */
regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
SUN50I_THS_FILTER_EN |
SUN50I_THS_FILTER_TYPE(1));
/* period = (x + 1) * 4096 / clkin; ~10ms */
regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
SUN50I_H6_THS_PC_TEMP_PERIOD(58));
/* enable sensor */
val = GENMASK(tmdev->chip->sensor_num - 1, 0);
regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
/* thermal data interrupt enable */
val = GENMASK(tmdev->chip->sensor_num - 1, 0);
regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
return 0;
}
static int sun8i_ths_register(struct ths_device *tmdev)
{
struct thermal_zone_device *tzd;
int i;
for (i = 0; i < tmdev->chip->sensor_num; i++) {
tmdev->sensor[i].tmdev = tmdev;
tmdev->sensor[i].id = i;
tmdev->sensor[i].tzd =
devm_thermal_zone_of_sensor_register(tmdev->dev,
i,
&tmdev->sensor[i],
&ths_ops);
if (IS_ERR(tmdev->sensor[i].tzd))
return PTR_ERR(tzd);
}
return 0;
}
static int sun8i_ths_probe(struct platform_device *pdev)
{
struct ths_device *tmdev;
struct device *dev = &pdev->dev;
int ret, irq;
tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
if (!tmdev)
return -ENOMEM;
tmdev->dev = dev;
tmdev->chip = of_device_get_match_data(&pdev->dev);
if (!tmdev->chip)
return -EINVAL;
platform_set_drvdata(pdev, tmdev);
ret = sun8i_ths_resource_init(tmdev);
if (ret)
return ret;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
ret = sun50i_thermal_init(tmdev);
if (ret)
return ret;
ret = sun8i_ths_register(tmdev);
if (ret)
return ret;
/*
* Avoid entering the interrupt handler, the thermal device is not
* registered yet, we deffer the registration of the interrupt to
* the end.
*/
ret = devm_request_threaded_irq(dev, irq, NULL,
sun50i_h6_irq_thread,
IRQF_ONESHOT, "ths", tmdev);
if (ret)
return ret;
return ret;
}
static int sun8i_ths_remove(struct platform_device *pdev)
{
struct ths_device *tmdev = platform_get_drvdata(pdev);
clk_disable_unprepare(tmdev->bus_clk);
reset_control_assert(tmdev->reset);
return 0;
}
static const struct ths_thermal_chip sun50i_h6_ths = {
.sensor_num = 2,
};
static const struct of_device_id of_ths_match[] = {
{ .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, of_ths_match);
static struct platform_driver ths_driver = {
.probe = sun8i_ths_probe,
.remove = sun8i_ths_remove,
.driver = {
.name = "sun8i-thermal",
.of_match_table = of_ths_match,
},
};
module_platform_driver(ths_driver);
MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
MODULE_LICENSE("GPL v2");