// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2011 Alexander Stein <alexander.stein@systec-electronic.com>
*
* The LM95245 is a sensor chip made by TI / National Semiconductor.
* It reports up to two temperatures (its own plus an external one).
*
* This driver is based on lm95241.c
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/hwmon.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include <linux/slab.h>
static const unsigned short normal_i2c[] = {
0x18, 0x19, 0x29, 0x4c, 0x4d, I2C_CLIENT_END };
/* LM95245 registers */
/* general registers */
#define LM95245_REG_RW_CONFIG1 0x03
#define LM95245_REG_RW_CONVERS_RATE 0x04
#define LM95245_REG_W_ONE_SHOT 0x0F
/* diode configuration */
#define LM95245_REG_RW_CONFIG2 0xBF
#define LM95245_REG_RW_REMOTE_OFFH 0x11
#define LM95245_REG_RW_REMOTE_OFFL 0x12
/* status registers */
#define LM95245_REG_R_STATUS1 0x02
#define LM95245_REG_R_STATUS2 0x33
/* limit registers */
#define LM95245_REG_RW_REMOTE_OS_LIMIT 0x07
#define LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT 0x20
#define LM95245_REG_RW_REMOTE_TCRIT_LIMIT 0x19
#define LM95245_REG_RW_COMMON_HYSTERESIS 0x21
/* temperature signed */
#define LM95245_REG_R_LOCAL_TEMPH_S 0x00
#define LM95245_REG_R_LOCAL_TEMPL_S 0x30
#define LM95245_REG_R_REMOTE_TEMPH_S 0x01
#define LM95245_REG_R_REMOTE_TEMPL_S 0x10
/* temperature unsigned */
#define LM95245_REG_R_REMOTE_TEMPH_U 0x31
#define LM95245_REG_R_REMOTE_TEMPL_U 0x32
/* id registers */
#define LM95245_REG_R_MAN_ID 0xFE
#define LM95245_REG_R_CHIP_ID 0xFF
/* LM95245 specific bitfields */
#define CFG_STOP 0x40
#define CFG_REMOTE_TCRIT_MASK 0x10
#define CFG_REMOTE_OS_MASK 0x08
#define CFG_LOCAL_TCRIT_MASK 0x04
#define CFG_LOCAL_OS_MASK 0x02
#define CFG2_OS_A0 0x40
#define CFG2_DIODE_FAULT_OS 0x20
#define CFG2_DIODE_FAULT_TCRIT 0x10
#define CFG2_REMOTE_TT 0x08
#define CFG2_REMOTE_FILTER_DIS 0x00
#define CFG2_REMOTE_FILTER_EN 0x06
/* conversation rate in ms */
#define RATE_CR0063 0x00
#define RATE_CR0364 0x01
#define RATE_CR1000 0x02
#define RATE_CR2500 0x03
#define STATUS1_ROS 0x10
#define STATUS1_DIODE_FAULT 0x04
#define STATUS1_RTCRIT 0x02
#define STATUS1_LOC 0x01
#define MANUFACTURER_ID 0x01
#define LM95235_REVISION 0xB1
#define LM95245_REVISION 0xB3
/* Client data (each client gets its own) */
struct lm95245_data {
struct regmap *regmap;
struct mutex update_lock;
int interval; /* in msecs */
};
/* Conversions */
static int temp_from_reg_unsigned(u8 val_h, u8 val_l)
{
return val_h * 1000 + val_l * 1000 / 256;
}
static int temp_from_reg_signed(u8 val_h, u8 val_l)
{
if (val_h & 0x80)
return (val_h - 0x100) * 1000;
return temp_from_reg_unsigned(val_h, val_l);
}
static int lm95245_read_conversion_rate(struct lm95245_data *data)
{
unsigned int rate;
int ret;
ret = regmap_read(data->regmap, LM95245_REG_RW_CONVERS_RATE, &rate);
if (ret < 0)
return ret;
switch (rate) {
case RATE_CR0063:
data->interval = 63;
break;
case RATE_CR0364:
data->interval = 364;
break;
case RATE_CR1000:
data->interval = 1000;
break;
case RATE_CR2500:
default:
data->interval = 2500;
break;
}
return 0;
}
static int lm95245_set_conversion_rate(struct lm95245_data *data, long interval)
{
int ret, rate;
if (interval <= 63) {
interval = 63;
rate = RATE_CR0063;
} else if (interval <= 364) {
interval = 364;
rate = RATE_CR0364;
} else if (interval <= 1000) {
interval = 1000;
rate = RATE_CR1000;
} else {
interval = 2500;
rate = RATE_CR2500;
}
ret = regmap_write(data->regmap, LM95245_REG_RW_CONVERS_RATE, rate);
if (ret < 0)
return ret;
data->interval = interval;
return 0;
}
static int lm95245_read_temp(struct device *dev, u32 attr, int channel,
long *val)
{
struct lm95245_data *data = dev_get_drvdata(dev);
struct regmap *regmap = data->regmap;
int ret, regl, regh, regvall, regvalh;
switch (attr) {
case hwmon_temp_input:
regl = channel ? LM95245_REG_R_REMOTE_TEMPL_S :
LM95245_REG_R_LOCAL_TEMPL_S;
regh = channel ? LM95245_REG_R_REMOTE_TEMPH_S :
LM95245_REG_R_LOCAL_TEMPH_S;
ret = regmap_read(regmap, regl, ®vall);
if (ret < 0)
return ret;
ret = regmap_read(regmap, regh, ®valh);
if (ret < 0)
return ret;
/*
* Local temp is always signed.
* Remote temp has both signed and unsigned data.
* Use signed calculation for remote if signed bit is set
* or if reported temperature is below signed limit.
*/
if (!channel || (regvalh & 0x80) || regvalh < 0x7f) {
*val = temp_from_reg_signed(regvalh, regvall);
return 0;
}
ret = regmap_read(regmap, LM95245_REG_R_REMOTE_TEMPL_U,
®vall);
if (ret < 0)
return ret;
ret = regmap_read(regmap, LM95245_REG_R_REMOTE_TEMPH_U,
®valh);
if (ret < 0)
return ret;
*val = temp_from_reg_unsigned(regvalh, regvall);
return 0;
case hwmon_temp_max:
ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT,
®valh);
if (ret < 0)
return ret;
*val = regvalh * 1000;
return 0;
case hwmon_temp_crit:
regh = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT :
LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT;
ret = regmap_read(regmap, regh, ®valh);
if (ret < 0)
return ret;
*val = regvalh * 1000;
return 0;
case hwmon_temp_max_hyst:
ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT,
®valh);
if (ret < 0)
return ret;
ret = regmap_read(regmap, LM95245_REG_RW_COMMON_HYSTERESIS,
®vall);
if (ret < 0)
return ret;
*val = (regvalh - regvall) * 1000;
return 0;
case hwmon_temp_crit_hyst:
regh = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT :
LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT;
ret = regmap_read(regmap, regh, ®valh);
if (ret < 0)
return ret;
ret = regmap_read(regmap, LM95245_REG_RW_COMMON_HYSTERESIS,
®vall);
if (ret < 0)
return ret;
*val = (regvalh - regvall) * 1000;
return 0;
case hwmon_temp_type:
ret = regmap_read(regmap, LM95245_REG_RW_CONFIG2, ®valh);
if (ret < 0)
return ret;
*val = (regvalh & CFG2_REMOTE_TT) ? 1 : 2;
return 0;
case hwmon_temp_offset:
ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OFFL,
®vall);
if (ret < 0)
return ret;
ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OFFH,
®valh);
if (ret < 0)
return ret;
*val = temp_from_reg_signed(regvalh, regvall);
return 0;
case hwmon_temp_max_alarm:
ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh);
if (ret < 0)
return ret;
*val = !!(regvalh & STATUS1_ROS);
return 0;
case hwmon_temp_crit_alarm:
ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh);
if (ret < 0)
return ret;
*val = !!(regvalh & (channel ? STATUS1_RTCRIT : STATUS1_LOC));
return 0;
case hwmon_temp_fault:
ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh);
if (ret < 0)
return ret;
*val = !!(regvalh & STATUS1_DIODE_FAULT);
return 0;
default:
return -EOPNOTSUPP;
}
}
static int lm95245_write_temp(struct device *dev, u32 attr, int channel,
long val)
{
struct lm95245_data *data = dev_get_drvdata(dev);
struct regmap *regmap = data->regmap;
unsigned int regval;
int ret, reg;
switch (attr) {
case hwmon_temp_max:
val = clamp_val(val / 1000, 0, 255);
ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT, val);
return ret;
case hwmon_temp_crit:
reg = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT :
LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT;
val = clamp_val(val / 1000, 0, channel ? 255 : 127);
ret = regmap_write(regmap, reg, val);
return ret;
case hwmon_temp_crit_hyst:
mutex_lock(&data->update_lock);
ret = regmap_read(regmap, LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT,
®val);
if (ret < 0) {
mutex_unlock(&data->update_lock);
return ret;
}
/* Clamp to reasonable range to prevent overflow */
val = clamp_val(val, -1000000, 1000000);
val = regval - val / 1000;
val = clamp_val(val, 0, 31);
ret = regmap_write(regmap, LM95245_REG_RW_COMMON_HYSTERESIS,
val);
mutex_unlock(&data->update_lock);
return ret;
case hwmon_temp_offset:
val = clamp_val(val, -128000, 127875);
val = val * 256 / 1000;
mutex_lock(&data->update_lock);
ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OFFL,
val & 0xe0);
if (ret < 0) {
mutex_unlock(&data->update_lock);
return ret;
}
ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OFFH,
(val >> 8) & 0xff);
mutex_unlock(&data->update_lock);
return ret;
case hwmon_temp_type:
if (val != 1 && val != 2)
return -EINVAL;
ret = regmap_update_bits(regmap, LM95245_REG_RW_CONFIG2,
CFG2_REMOTE_TT,
val == 1 ? CFG2_REMOTE_TT : 0);
return ret;
default:
return -EOPNOTSUPP;
}
}
static int lm95245_read_chip(struct device *dev, u32 attr, int channel,
long *val)
{
struct lm95245_data *data = dev_get_drvdata(dev);
switch (attr) {
case hwmon_chip_update_interval:
*val = data->interval;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int lm95245_write_chip(struct device *dev, u32 attr, int channel,
long val)
{
struct lm95245_data *data = dev_get_drvdata(dev);
int ret;
switch (attr) {
case hwmon_chip_update_interval:
mutex_lock(&data->update_lock);
ret = lm95245_set_conversion_rate(data, val);
mutex_unlock(&data->update_lock);
return ret;
default:
return -EOPNOTSUPP;
}
}
static int lm95245_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_chip:
return lm95245_read_chip(dev, attr, channel, val);
case hwmon_temp:
return lm95245_read_temp(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static int lm95245_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
switch (type) {
case hwmon_chip:
return lm95245_write_chip(dev, attr, channel, val);
case hwmon_temp:
return lm95245_write_temp(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t lm95245_temp_is_visible(const void *data, u32 attr, int channel)
{
switch (attr) {
case hwmon_temp_input:
case hwmon_temp_max_alarm:
case hwmon_temp_max_hyst:
case hwmon_temp_crit_alarm:
case hwmon_temp_fault:
return 0444;
case hwmon_temp_type:
case hwmon_temp_max:
case hwmon_temp_crit:
case hwmon_temp_offset:
return 0644;
case hwmon_temp_crit_hyst:
return (channel == 0) ? 0644 : 0444;
default:
return 0;
}
}
static umode_t lm95245_is_visible(const void *data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
switch (type) {
case hwmon_chip:
switch (attr) {
case hwmon_chip_update_interval:
return 0644;
default:
return 0;
}
case hwmon_temp:
return lm95245_temp_is_visible(data, attr, channel);
default:
return 0;
}
}
/* Return 0 if detection is successful, -ENODEV otherwise */
static int lm95245_detect(struct i2c_client *new_client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
int address = new_client->addr;
const char *name;
int rev, id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
id = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_MAN_ID);
if (id != MANUFACTURER_ID)
return -ENODEV;
rev = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_CHIP_ID);
switch (rev) {
case LM95235_REVISION:
if (address != 0x18 && address != 0x29 && address != 0x4c)
return -ENODEV;
name = "lm95235";
break;
case LM95245_REVISION:
name = "lm95245";
break;
default:
return -ENODEV;
}
strlcpy(info->type, name, I2C_NAME_SIZE);
return 0;
}
static int lm95245_init_client(struct lm95245_data *data)
{
int ret;
ret = lm95245_read_conversion_rate(data);
if (ret < 0)
return ret;
return regmap_update_bits(data->regmap, LM95245_REG_RW_CONFIG1,
CFG_STOP, 0);
}
static bool lm95245_is_writeable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case LM95245_REG_RW_CONFIG1:
case LM95245_REG_RW_CONVERS_RATE:
case LM95245_REG_W_ONE_SHOT:
case LM95245_REG_RW_CONFIG2:
case LM95245_REG_RW_REMOTE_OFFH:
case LM95245_REG_RW_REMOTE_OFFL:
case LM95245_REG_RW_REMOTE_OS_LIMIT:
case LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT:
case LM95245_REG_RW_REMOTE_TCRIT_LIMIT:
case LM95245_REG_RW_COMMON_HYSTERESIS:
return true;
default:
return false;
}
}
static bool lm95245_is_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case LM95245_REG_R_STATUS1:
case LM95245_REG_R_STATUS2:
case LM95245_REG_R_LOCAL_TEMPH_S:
case LM95245_REG_R_LOCAL_TEMPL_S:
case LM95245_REG_R_REMOTE_TEMPH_S:
case LM95245_REG_R_REMOTE_TEMPL_S:
case LM95245_REG_R_REMOTE_TEMPH_U:
case LM95245_REG_R_REMOTE_TEMPL_U:
return true;
default:
return false;
}
}
static const struct regmap_config lm95245_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.writeable_reg = lm95245_is_writeable_reg,
.volatile_reg = lm95245_is_volatile_reg,
.cache_type = REGCACHE_RBTREE,
.use_single_read = true,
.use_single_write = true,
};
static const struct hwmon_channel_info *lm95245_info[] = {
HWMON_CHANNEL_INFO(chip,
HWMON_C_UPDATE_INTERVAL),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_HYST |
HWMON_T_CRIT_ALARM,
HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_FAULT |
HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
HWMON_T_TYPE | HWMON_T_OFFSET),
NULL
};
static const struct hwmon_ops lm95245_hwmon_ops = {
.is_visible = lm95245_is_visible,
.read = lm95245_read,
.write = lm95245_write,
};
static const struct hwmon_chip_info lm95245_chip_info = {
.ops = &lm95245_hwmon_ops,
.info = lm95245_info,
};
static int lm95245_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct lm95245_data *data;
struct device *hwmon_dev;
int ret;
data = devm_kzalloc(dev, sizeof(struct lm95245_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->regmap = devm_regmap_init_i2c(client, &lm95245_regmap_config);
if (IS_ERR(data->regmap))
return PTR_ERR(data->regmap);
mutex_init(&data->update_lock);
/* Initialize the LM95245 chip */
ret = lm95245_init_client(data);
if (ret < 0)
return ret;
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
data,
&lm95245_chip_info,
NULL);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
/* Driver data (common to all clients) */
static const struct i2c_device_id lm95245_id[] = {
{ "lm95235", 0 },
{ "lm95245", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lm95245_id);
static const struct of_device_id __maybe_unused lm95245_of_match[] = {
{ .compatible = "national,lm95235" },
{ .compatible = "national,lm95245" },
{ },
};
MODULE_DEVICE_TABLE(of, lm95245_of_match);
static struct i2c_driver lm95245_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "lm95245",
.of_match_table = of_match_ptr(lm95245_of_match),
},
.probe_new = lm95245_probe,
.id_table = lm95245_id,
.detect = lm95245_detect,
.address_list = normal_i2c,
};
module_i2c_driver(lm95245_driver);
MODULE_AUTHOR("Alexander Stein <alexander.stein@systec-electronic.com>");
MODULE_DESCRIPTION("LM95235/LM95245 sensor driver");
MODULE_LICENSE("GPL");
