// SPDX-License-Identifier: GPL-2.0-only
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/hwmon.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/polynomial.h>
#include <linux/regmap.h>
/*
* The original translation formulae of the temperature (in degrees of Celsius)
* are as follows:
*
* T = -3.4627e-11*(N^4) + 1.1023e-7*(N^3) + -1.9165e-4*(N^2) +
* 3.0604e-1*(N^1) + -5.6197e1
*
* where [-56.197, 136.402]C and N = [0, 1023].
*
* They must be accordingly altered to be suitable for the integer arithmetics.
* The technique is called 'factor redistribution', which just makes sure the
* multiplications and divisions are made so to have a result of the operations
* within the integer numbers limit. In addition we need to translate the
* formulae to accept millidegrees of Celsius. Here what it looks like after
* the alterations:
*
* T = -34627e-12*(N^4) + 110230e-9*(N^3) + -191650e-6*(N^2) +
* 306040e-3*(N^1) + -56197
*
* where T = [-56197, 136402]mC and N = [0, 1023].
*/
static const struct polynomial poly_N_to_temp = {
.terms = {
{4, -34627, 1000, 1},
{3, 110230, 1000, 1},
{2, -191650, 1000, 1},
{1, 306040, 1000, 1},
{0, -56197, 1, 1}
}
};
#define PVT_SENSOR_CTRL 0x0 /* unused */
#define PVT_SENSOR_CFG 0x4
#define SENSOR_CFG_CLK_CFG GENMASK(27, 20)
#define SENSOR_CFG_TRIM_VAL GENMASK(13, 9)
#define SENSOR_CFG_SAMPLE_ENA BIT(8)
#define SENSOR_CFG_START_CAPTURE BIT(7)
#define SENSOR_CFG_CONTINIOUS_MODE BIT(6)
#define SENSOR_CFG_PSAMPLE_ENA GENMASK(1, 0)
#define PVT_SENSOR_STAT 0x8
#define SENSOR_STAT_DATA_VALID BIT(10)
#define SENSOR_STAT_DATA GENMASK(9, 0)
#define FAN_CFG 0x0
#define FAN_CFG_DUTY_CYCLE GENMASK(23, 16)
#define INV_POL BIT(3)
#define GATE_ENA BIT(2)
#define PWM_OPEN_COL_ENA BIT(1)
#define FAN_STAT_CFG BIT(0)
#define FAN_PWM_FREQ 0x4
#define FAN_PWM_CYC_10US GENMASK(25, 15)
#define FAN_PWM_FREQ_FREQ GENMASK(14, 0)
#define FAN_CNT 0xc
#define FAN_CNT_DATA GENMASK(15, 0)
#define LAN966X_PVT_CLK 1200000 /* 1.2 MHz */
struct lan966x_hwmon {
struct regmap *regmap_pvt;
struct regmap *regmap_fan;
struct clk *clk;
unsigned long clk_rate;
};
static int lan966x_hwmon_read_temp(struct device *dev, long *val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
unsigned int data;
int ret;
ret = regmap_read(hwmon->regmap_pvt, PVT_SENSOR_STAT, &data);
if (ret < 0)
return ret;
if (!(data & SENSOR_STAT_DATA_VALID))
return -ENODATA;
*val = polynomial_calc(&poly_N_to_temp,
FIELD_GET(SENSOR_STAT_DATA, data));
return 0;
}
static int lan966x_hwmon_read_fan(struct device *dev, long *val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
unsigned int data;
int ret;
ret = regmap_read(hwmon->regmap_fan, FAN_CNT, &data);
if (ret < 0)
return ret;
/*
* Data is given in pulses per second. Assume two pulses
* per revolution.
*/
*val = FIELD_GET(FAN_CNT_DATA, data) * 60 / 2;
return 0;
}
static int lan966x_hwmon_read_pwm(struct device *dev, long *val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
unsigned int data;
int ret;
ret = regmap_read(hwmon->regmap_fan, FAN_CFG, &data);
if (ret < 0)
return ret;
*val = FIELD_GET(FAN_CFG_DUTY_CYCLE, data);
return 0;
}
static int lan966x_hwmon_read_pwm_freq(struct device *dev, long *val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
unsigned long tmp;
unsigned int data;
int ret;
ret = regmap_read(hwmon->regmap_fan, FAN_PWM_FREQ, &data);
if (ret < 0)
return ret;
/*
* Datasheet says it is sys_clk / 256 / pwm_freq. But in reality
* it is sys_clk / 256 / (pwm_freq + 1).
*/
data = FIELD_GET(FAN_PWM_FREQ_FREQ, data) + 1;
tmp = DIV_ROUND_CLOSEST(hwmon->clk_rate, 256);
*val = DIV_ROUND_CLOSEST(tmp, data);
return 0;
}
static int lan966x_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_temp:
return lan966x_hwmon_read_temp(dev, val);
case hwmon_fan:
return lan966x_hwmon_read_fan(dev, val);
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
return lan966x_hwmon_read_pwm(dev, val);
case hwmon_pwm_freq:
return lan966x_hwmon_read_pwm_freq(dev, val);
default:
return -EOPNOTSUPP;
}
default:
return -EOPNOTSUPP;
}
}
static int lan966x_hwmon_write_pwm(struct device *dev, long val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
if (val < 0 || val > 255)
return -EINVAL;
return regmap_update_bits(hwmon->regmap_fan, FAN_CFG,
FAN_CFG_DUTY_CYCLE,
FIELD_PREP(FAN_CFG_DUTY_CYCLE, val));
}
static int lan966x_hwmon_write_pwm_freq(struct device *dev, long val)
{
struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
if (val <= 0)
return -EINVAL;
val = DIV_ROUND_CLOSEST(hwmon->clk_rate, val);
val = DIV_ROUND_CLOSEST(val, 256) - 1;
val = clamp_val(val, 0, FAN_PWM_FREQ_FREQ);
return regmap_update_bits(hwmon->regmap_fan, FAN_PWM_FREQ,
FAN_PWM_FREQ_FREQ,
FIELD_PREP(FAN_PWM_FREQ_FREQ, val));
}
static int lan966x_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
switch (type) {
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
return lan966x_hwmon_write_pwm(dev, val);
case hwmon_pwm_freq:
return lan966x_hwmon_write_pwm_freq(dev, val);
default:
return -EOPNOTSUPP;
}
default:
return -EOPNOTSUPP;
}
}
static umode_t lan966x_hwmon_is_visible(const void *data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
umode_t mode = 0;
switch (type) {
case hwmon_temp:
switch (attr) {
case hwmon_temp_input:
mode = 0444;
break;
default:
break;
}
break;
case hwmon_fan:
switch (attr) {
case hwmon_fan_input:
mode = 0444;
break;
default:
break;
}
break;
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
case hwmon_pwm_freq:
mode = 0644;
break;
default:
break;
}
break;
default:
break;
}
return mode;
}
static const struct hwmon_channel_info * const lan966x_hwmon_info[] = {
HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT),
HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_FREQ),
NULL
};
static const struct hwmon_ops lan966x_hwmon_ops = {
.is_visible = lan966x_hwmon_is_visible,
.read = lan966x_hwmon_read,
.write = lan966x_hwmon_write,
};
static const struct hwmon_chip_info lan966x_hwmon_chip_info = {
.ops = &lan966x_hwmon_ops,
.info = lan966x_hwmon_info,
};
static void lan966x_hwmon_disable(void *data)
{
struct lan966x_hwmon *hwmon = data;
regmap_update_bits(hwmon->regmap_pvt, PVT_SENSOR_CFG,
SENSOR_CFG_SAMPLE_ENA | SENSOR_CFG_CONTINIOUS_MODE,
0);
}
static int lan966x_hwmon_enable(struct device *dev,
struct lan966x_hwmon *hwmon)
{
unsigned int mask = SENSOR_CFG_CLK_CFG |
SENSOR_CFG_SAMPLE_ENA |
SENSOR_CFG_START_CAPTURE |
SENSOR_CFG_CONTINIOUS_MODE |
SENSOR_CFG_PSAMPLE_ENA;
unsigned int val;
unsigned int div;
int ret;
/* enable continuous mode */
val = SENSOR_CFG_SAMPLE_ENA | SENSOR_CFG_CONTINIOUS_MODE;
/* set PVT clock to be between 1.15 and 1.25 MHz */
div = DIV_ROUND_CLOSEST(hwmon->clk_rate, LAN966X_PVT_CLK);
val |= FIELD_PREP(SENSOR_CFG_CLK_CFG, div);
ret = regmap_update_bits(hwmon->regmap_pvt, PVT_SENSOR_CFG,
mask, val);
if (ret)
return ret;
return devm_add_action_or_reset(dev, lan966x_hwmon_disable, hwmon);
}
static struct regmap *lan966x_init_regmap(struct platform_device *pdev,
const char *name)
{
struct regmap_config regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
};
void __iomem *base;
base = devm_platform_ioremap_resource_byname(pdev, name);
if (IS_ERR(base))
return ERR_CAST(base);
regmap_config.name = name;
return devm_regmap_init_mmio(&pdev->dev, base, ®map_config);
}
static int lan966x_hwmon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct lan966x_hwmon *hwmon;
struct device *hwmon_dev;
int ret;
hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
if (!hwmon)
return -ENOMEM;
hwmon->clk = devm_clk_get_enabled(dev, NULL);
if (IS_ERR(hwmon->clk))
return dev_err_probe(dev, PTR_ERR(hwmon->clk),
"failed to get clock\n");
hwmon->clk_rate = clk_get_rate(hwmon->clk);
hwmon->regmap_pvt = lan966x_init_regmap(pdev, "pvt");
if (IS_ERR(hwmon->regmap_pvt))
return dev_err_probe(dev, PTR_ERR(hwmon->regmap_pvt),
"failed to get regmap for PVT registers\n");
hwmon->regmap_fan = lan966x_init_regmap(pdev, "fan");
if (IS_ERR(hwmon->regmap_fan))
return dev_err_probe(dev, PTR_ERR(hwmon->regmap_fan),
"failed to get regmap for fan registers\n");
ret = lan966x_hwmon_enable(dev, hwmon);
if (ret)
return dev_err_probe(dev, ret, "failed to enable sensor\n");
hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
"lan966x_hwmon", hwmon,
&lan966x_hwmon_chip_info, NULL);
if (IS_ERR(hwmon_dev))
return dev_err_probe(dev, PTR_ERR(hwmon_dev),
"failed to register hwmon device\n");
return 0;
}
static const struct of_device_id lan966x_hwmon_of_match[] = {
{ .compatible = "microchip,lan9668-hwmon" },
{}
};
MODULE_DEVICE_TABLE(of, lan966x_hwmon_of_match);
static struct platform_driver lan966x_hwmon_driver = {
.probe = lan966x_hwmon_probe,
.driver = {
.name = "lan966x-hwmon",
.of_match_table = lan966x_hwmon_of_match,
},
};
module_platform_driver(lan966x_hwmon_driver);
MODULE_DESCRIPTION("LAN966x Hardware Monitoring Driver");
MODULE_AUTHOR("Michael Walle <[email protected]>");
MODULE_LICENSE("GPL");
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