// SPDX-License-Identifier: GPL-2.0-or-later
/* Driver for the Texas Instruments TMP464 SMBus temperature sensor IC.
* Supported models: TMP464, TMP468
* Copyright (C) 2022 Agathe Porte <agathe.porte@nokia.com>
* Preliminary support by:
* Lionel Pouliquen <lionel.lp.pouliquen@nokia.com>
*/
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, I2C_CLIENT_END };
#define TMP464_NUM_CHANNELS 5 /* chan 0 is internal, 1-4 are remote */
#define TMP468_NUM_CHANNELS 9 /* chan 0 is internal, 1-8 are remote */
#define MAX_CHANNELS 9
#define TMP464_TEMP_REG(channel) (channel)
#define TMP464_TEMP_OFFSET_REG(channel) (0x40 + ((channel) - 1) * 8)
#define TMP464_N_FACTOR_REG(channel) (0x41 + ((channel) - 1) * 8)
static const u8 TMP464_THERM_LIMIT[MAX_CHANNELS] = {
0x39, 0x42, 0x4A, 0x52, 0x5A, 0x62, 0x6a, 0x72, 0x7a };
static const u8 TMP464_THERM2_LIMIT[MAX_CHANNELS] = {
0x3A, 0x43, 0x4B, 0x53, 0x5B, 0x63, 0x6b, 0x73, 0x7b };
#define TMP464_THERM_STATUS_REG 0x21
#define TMP464_THERM2_STATUS_REG 0x22
#define TMP464_REMOTE_OPEN_REG 0x23
#define TMP464_CONFIG_REG 0x30
#define TMP464_TEMP_HYST_REG 0x38
#define TMP464_LOCK_REG 0xc4
/* Identification */
#define TMP464_MANUFACTURER_ID_REG 0xFE
#define TMP464_DEVICE_ID_REG 0xFF
/* Flags */
#define TMP464_CONFIG_SHUTDOWN BIT(5)
#define TMP464_CONFIG_RANGE 0x04
#define TMP464_CONFIG_REG_REN(x) (BIT(7 + (x)))
#define TMP464_CONFIG_REG_REN_MASK GENMASK(15, 7)
#define TMP464_CONFIG_CONVERSION_RATE_B0 2
#define TMP464_CONFIG_CONVERSION_RATE_B2 4
#define TMP464_CONFIG_CONVERSION_RATE_MASK GENMASK(TMP464_CONFIG_CONVERSION_RATE_B2, \
TMP464_CONFIG_CONVERSION_RATE_B0)
#define TMP464_UNLOCK_VAL 0xeb19
#define TMP464_LOCK_VAL 0x5ca6
#define TMP464_LOCKED 0x8000
/* Manufacturer / Device ID's */
#define TMP464_MANUFACTURER_ID 0x5449
#define TMP464_DEVICE_ID 0x1468
#define TMP468_DEVICE_ID 0x0468
static const struct i2c_device_id tmp464_id[] = {
{ "tmp464", TMP464_NUM_CHANNELS },
{ "tmp468", TMP468_NUM_CHANNELS },
{ }
};
MODULE_DEVICE_TABLE(i2c, tmp464_id);
static const struct of_device_id __maybe_unused tmp464_of_match[] = {
{
.compatible = "ti,tmp464",
.data = (void *)TMP464_NUM_CHANNELS
},
{
.compatible = "ti,tmp468",
.data = (void *)TMP468_NUM_CHANNELS
},
{},
};
MODULE_DEVICE_TABLE(of, tmp464_of_match);
struct tmp464_channel {
const char *label;
bool enabled;
};
struct tmp464_data {
struct regmap *regmap;
struct mutex update_lock;
int channels;
s16 config_orig;
u16 open_reg;
unsigned long last_updated;
bool valid;
int update_interval;
struct tmp464_channel channel[MAX_CHANNELS];
};
static int temp_from_reg(s16 reg)
{
return DIV_ROUND_CLOSEST((reg >> 3) * 625, 10);
}
static s16 temp_to_limit_reg(long temp)
{
return DIV_ROUND_CLOSEST(temp, 500) << 6;
}
static s16 temp_to_offset_reg(long temp)
{
return DIV_ROUND_CLOSEST(temp * 10, 625) << 3;
}
static int tmp464_enable_channels(struct tmp464_data *data)
{
struct regmap *regmap = data->regmap;
u16 enable = 0;
int i;
for (i = 0; i < data->channels; i++)
if (data->channel[i].enabled)
enable |= TMP464_CONFIG_REG_REN(i);
return regmap_update_bits(regmap, TMP464_CONFIG_REG, TMP464_CONFIG_REG_REN_MASK, enable);
}
static int tmp464_chip_read(struct device *dev, u32 attr, int channel, long *val)
{
struct tmp464_data *data = dev_get_drvdata(dev);
switch (attr) {
case hwmon_chip_update_interval:
*val = data->update_interval;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int tmp464_temp_read(struct device *dev, u32 attr, int channel, long *val)
{
struct tmp464_data *data = dev_get_drvdata(dev);
struct regmap *regmap = data->regmap;
unsigned int regval, regval2;
int err = 0;
mutex_lock(&data->update_lock);
switch (attr) {
case hwmon_temp_max_alarm:
err = regmap_read(regmap, TMP464_THERM_STATUS_REG, ®val);
if (err < 0)
break;
*val = !!(regval & BIT(channel + 7));
break;
case hwmon_temp_crit_alarm:
err = regmap_read(regmap, TMP464_THERM2_STATUS_REG, ®val);
if (err < 0)
break;
*val = !!(regval & BIT(channel + 7));
break;
case hwmon_temp_fault:
/*
* The chip clears TMP464_REMOTE_OPEN_REG after it is read
* and only updates it after the next measurement cycle is
* complete. That means we have to cache the value internally
* for one measurement cycle and report the cached value.
*/
if (!data->valid || time_after(jiffies, data->last_updated +
msecs_to_jiffies(data->update_interval))) {
err = regmap_read(regmap, TMP464_REMOTE_OPEN_REG, ®val);
if (err < 0)
break;
data->open_reg = regval;
data->last_updated = jiffies;
data->valid = true;
}
*val = !!(data->open_reg & BIT(channel + 7));
break;
case hwmon_temp_max_hyst:
err = regmap_read(regmap, TMP464_THERM_LIMIT[channel], ®val);
if (err < 0)
break;
err = regmap_read(regmap, TMP464_TEMP_HYST_REG, ®val2);
if (err < 0)
break;
regval -= regval2;
*val = temp_from_reg(regval);
break;
case hwmon_temp_max:
err = regmap_read(regmap, TMP464_THERM_LIMIT[channel], ®val);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_crit_hyst:
err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], ®val);
if (err < 0)
break;
err = regmap_read(regmap, TMP464_TEMP_HYST_REG, ®val2);
if (err < 0)
break;
regval -= regval2;
*val = temp_from_reg(regval);
break;
case hwmon_temp_crit:
err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], ®val);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_offset:
err = regmap_read(regmap, TMP464_TEMP_OFFSET_REG(channel), ®val);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_input:
if (!data->channel[channel].enabled) {
err = -ENODATA;
break;
}
err = regmap_read(regmap, TMP464_TEMP_REG(channel), ®val);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_enable:
*val = data->channel[channel].enabled;
break;
default:
err = -EOPNOTSUPP;
break;
}
mutex_unlock(&data->update_lock);
return err;
}
static int tmp464_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_chip:
return tmp464_chip_read(dev, attr, channel, val);
case hwmon_temp:
return tmp464_temp_read(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static int tmp464_read_string(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, const char **str)
{
struct tmp464_data *data = dev_get_drvdata(dev);
*str = data->channel[channel].label;
return 0;
}
static int tmp464_set_convrate(struct tmp464_data *data, long interval)
{
int rate;
/*
* For valid rates, interval in milli-seconds can be calculated as
* interval = 125 << (7 - rate);
* or
* interval = (1 << (7 - rate)) * 125;
* The rate is therefore
* rate = 7 - __fls(interval / 125);
* and the rounded rate is
* rate = 7 - __fls(interval * 4 / (125 * 3));
* Use clamp_val() to avoid overflows, and to ensure valid input
* for __fls.
*/
interval = clamp_val(interval, 125, 16000);
rate = 7 - __fls(interval * 4 / (125 * 3));
data->update_interval = 125 << (7 - rate);
return regmap_update_bits(data->regmap, TMP464_CONFIG_REG,
TMP464_CONFIG_CONVERSION_RATE_MASK,
rate << TMP464_CONFIG_CONVERSION_RATE_B0);
}
static int tmp464_chip_write(struct tmp464_data *data, u32 attr, int channel, long val)
{
switch (attr) {
case hwmon_chip_update_interval:
return tmp464_set_convrate(data, val);
default:
return -EOPNOTSUPP;
}
}
static int tmp464_temp_write(struct tmp464_data *data, u32 attr, int channel, long val)
{
struct regmap *regmap = data->regmap;
unsigned int regval;
int err = 0;
switch (attr) {
case hwmon_temp_max_hyst:
err = regmap_read(regmap, TMP464_THERM_LIMIT[0], ®val);
if (err < 0)
break;
val = clamp_val(val, -256000, 256000); /* prevent overflow/underflow */
val = clamp_val(temp_from_reg(regval) - val, 0, 255000);
err = regmap_write(regmap, TMP464_TEMP_HYST_REG,
DIV_ROUND_CLOSEST(val, 1000) << 7);
break;
case hwmon_temp_max:
val = temp_to_limit_reg(clamp_val(val, -255000, 255500));
err = regmap_write(regmap, TMP464_THERM_LIMIT[channel], val);
break;
case hwmon_temp_crit:
val = temp_to_limit_reg(clamp_val(val, -255000, 255500));
err = regmap_write(regmap, TMP464_THERM2_LIMIT[channel], val);
break;
case hwmon_temp_offset:
val = temp_to_offset_reg(clamp_val(val, -128000, 127937));
err = regmap_write(regmap, TMP464_TEMP_OFFSET_REG(channel), val);
break;
case hwmon_temp_enable:
data->channel[channel].enabled = !!val;
err = tmp464_enable_channels(data);
break;
default:
err = -EOPNOTSUPP;
break;
}
return err;
}
static int tmp464_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
struct tmp464_data *data = dev_get_drvdata(dev);
int err;
mutex_lock(&data->update_lock);
switch (type) {
case hwmon_chip:
err = tmp464_chip_write(data, attr, channel, val);
break;
case hwmon_temp:
err = tmp464_temp_write(data, attr, channel, val);
break;
default:
err = -EOPNOTSUPP;
break;
}
mutex_unlock(&data->update_lock);
return err;
}
static umode_t tmp464_is_visible(const void *_data, enum hwmon_sensor_types type,
u32 attr, int channel)
{
const struct tmp464_data *data = _data;
if (channel >= data->channels)
return 0;
if (type == hwmon_chip) {
if (attr == hwmon_chip_update_interval)
return 0644;
return 0;
}
switch (attr) {
case hwmon_temp_input:
case hwmon_temp_max_alarm:
case hwmon_temp_crit_alarm:
case hwmon_temp_crit_hyst:
return 0444;
case hwmon_temp_enable:
case hwmon_temp_max:
case hwmon_temp_crit:
return 0644;
case hwmon_temp_max_hyst:
if (!channel)
return 0644;
return 0444;
case hwmon_temp_label:
if (data->channel[channel].label)
return 0444;
return 0;
case hwmon_temp_fault:
if (channel)
return 0444;
return 0;
case hwmon_temp_offset:
if (channel)
return 0644;
return 0;
default:
return 0;
}
}
static void tmp464_restore_lock(void *regmap)
{
regmap_write(regmap, TMP464_LOCK_REG, TMP464_LOCK_VAL);
}
static void tmp464_restore_config(void *_data)
{
struct tmp464_data *data = _data;
regmap_write(data->regmap, TMP464_CONFIG_REG, data->config_orig);
}
static int tmp464_init_client(struct device *dev, struct tmp464_data *data)
{
struct regmap *regmap = data->regmap;
unsigned int regval;
int err;
err = regmap_read(regmap, TMP464_LOCK_REG, ®val);
if (err)
return err;
if (regval == TMP464_LOCKED) {
/* Explicitly unlock chip if it is locked */
err = regmap_write(regmap, TMP464_LOCK_REG, TMP464_UNLOCK_VAL);
if (err)
return err;
/* and lock it again when unloading the driver */
err = devm_add_action_or_reset(dev, tmp464_restore_lock, regmap);
if (err)
return err;
}
err = regmap_read(regmap, TMP464_CONFIG_REG, ®val);
if (err)
return err;
data->config_orig = regval;
err = devm_add_action_or_reset(dev, tmp464_restore_config, data);
if (err)
return err;
/* Default to 500 ms update interval */
err = regmap_update_bits(regmap, TMP464_CONFIG_REG,
TMP464_CONFIG_CONVERSION_RATE_MASK | TMP464_CONFIG_SHUTDOWN,
BIT(TMP464_CONFIG_CONVERSION_RATE_B0) |
BIT(TMP464_CONFIG_CONVERSION_RATE_B2));
if (err)
return err;
data->update_interval = 500;
return tmp464_enable_channels(data);
}
static int tmp464_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
char *name, *chip;
int reg;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
reg = i2c_smbus_read_word_swapped(client, TMP464_MANUFACTURER_ID_REG);
if (reg < 0)
return reg;
if (reg != TMP464_MANUFACTURER_ID)
return -ENODEV;
/* Check for "always return zero" bits */
reg = i2c_smbus_read_word_swapped(client, TMP464_THERM_STATUS_REG);
if (reg < 0)
return reg;
if (reg & 0x1f)
return -ENODEV;
reg = i2c_smbus_read_word_swapped(client, TMP464_THERM2_STATUS_REG);
if (reg < 0)
return reg;
if (reg & 0x1f)
return -ENODEV;
reg = i2c_smbus_read_word_swapped(client, TMP464_DEVICE_ID_REG);
if (reg < 0)
return reg;
switch (reg) {
case TMP464_DEVICE_ID:
name = "tmp464";
chip = "TMP464";
break;
case TMP468_DEVICE_ID:
name = "tmp468";
chip = "TMP468";
break;
default:
return -ENODEV;
}
strscpy(info->type, name, I2C_NAME_SIZE);
dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n", chip, client->addr);
return 0;
}
static int tmp464_probe_child_from_dt(struct device *dev,
struct device_node *child,
struct tmp464_data *data)
{
struct regmap *regmap = data->regmap;
u32 channel;
s32 nfactor;
int err;
err = of_property_read_u32(child, "reg", &channel);
if (err) {
dev_err(dev, "missing reg property of %pOFn\n", child);
return err;
}
if (channel >= data->channels) {
dev_err(dev, "invalid reg %d of %pOFn\n", channel, child);
return -EINVAL;
}
of_property_read_string(child, "label", &data->channel[channel].label);
data->channel[channel].enabled = of_device_is_available(child);
err = of_property_read_s32(child, "ti,n-factor", &nfactor);
if (err && err != -EINVAL)
return err;
if (!err) {
if (channel == 0) {
dev_err(dev, "n-factor can't be set for internal channel\n");
return -EINVAL;
}
if (nfactor > 127 || nfactor < -128) {
dev_err(dev, "n-factor for channel %d invalid (%d)\n",
channel, nfactor);
return -EINVAL;
}
err = regmap_write(regmap, TMP464_N_FACTOR_REG(channel),
(nfactor << 8) & 0xff00);
if (err)
return err;
}
return 0;
}
static int tmp464_probe_from_dt(struct device *dev, struct tmp464_data *data)
{
const struct device_node *np = dev->of_node;
struct device_node *child;
int err;
for_each_child_of_node(np, child) {
if (strcmp(child->name, "channel"))
continue;
err = tmp464_probe_child_from_dt(dev, child, data);
if (err) {
of_node_put(child);
return err;
}
}
return 0;
}
static const struct hwmon_ops tmp464_ops = {
.is_visible = tmp464_is_visible,
.read = tmp464_read,
.read_string = tmp464_read_string,
.write = tmp464_write,
};
static const struct hwmon_channel_info *tmp464_info[] = {
HWMON_CHANNEL_INFO(chip,
HWMON_C_UPDATE_INTERVAL),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_CRIT |
HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE,
HWMON_T_INPUT | HWMON_T_OFFSET | HWMON_T_MAX | HWMON_T_MAX_HYST |
HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MAX_ALARM |
HWMON_T_CRIT_ALARM | HWMON_T_FAULT | HWMON_T_LABEL | HWMON_T_ENABLE),
NULL
};
static const struct hwmon_chip_info tmp464_chip_info = {
.ops = &tmp464_ops,
.info = tmp464_info,
};
/* regmap */
static bool tmp464_is_volatile_reg(struct device *dev, unsigned int reg)
{
return (reg < TMP464_TEMP_REG(TMP468_NUM_CHANNELS) ||
reg == TMP464_THERM_STATUS_REG ||
reg == TMP464_THERM2_STATUS_REG ||
reg == TMP464_REMOTE_OPEN_REG);
}
static const struct regmap_config tmp464_regmap_config = {
.reg_bits = 8,
.val_bits = 16,
.max_register = TMP464_DEVICE_ID_REG,
.volatile_reg = tmp464_is_volatile_reg,
.val_format_endian = REGMAP_ENDIAN_BIG,
.cache_type = REGCACHE_RBTREE,
.use_single_read = true,
.use_single_write = true,
};
static int tmp464_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct device *hwmon_dev;
struct tmp464_data *data;
int i, err;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
dev_err(&client->dev, "i2c functionality check failed\n");
return -ENODEV;
}
data = devm_kzalloc(dev, sizeof(struct tmp464_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_init(&data->update_lock);
if (dev->of_node)
data->channels = (int)(unsigned long)of_device_get_match_data(&client->dev);
else
data->channels = i2c_match_id(tmp464_id, client)->driver_data;
data->regmap = devm_regmap_init_i2c(client, &tmp464_regmap_config);
if (IS_ERR(data->regmap))
return PTR_ERR(data->regmap);
for (i = 0; i < data->channels; i++)
data->channel[i].enabled = true;
err = tmp464_init_client(dev, data);
if (err)
return err;
if (dev->of_node) {
err = tmp464_probe_from_dt(dev, data);
if (err)
return err;
}
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
data, &tmp464_chip_info, NULL);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static struct i2c_driver tmp464_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "tmp464",
.of_match_table = of_match_ptr(tmp464_of_match),
},
.probe_new = tmp464_probe,
.id_table = tmp464_id,
.detect = tmp464_detect,
.address_list = normal_i2c,
};
module_i2c_driver(tmp464_driver);
MODULE_AUTHOR("Agathe Porte <agathe.porte@nokia.com>");
MODULE_DESCRIPTION("Texas Instruments TMP464 temperature sensor driver");
MODULE_LICENSE("GPL");
