linux/drivers/hwmon/tmp464.c
Guenter Roeck 007e433cf0 hwmon: Add driver for Texas Instruments TMP464 and TMP468
Add support for Texas Instruments TMP464 and TMP468 temperature sensor
ICs.

TI's TMP464 is an I2C temperature sensor chip. This chip is similar
to TI's TMP421 chip, but with 16bit-wide registers (instead of
8bit-wide registers). The chip has one local sensor and four remote
sensors. TMP468 is similar to TMP464 but has one local and eight
remote sensors.

Originally-from: Agathe Porte <agathe.porte@nokia.com>
Cc: Agathe Porte <agathe.porte@nokia.com>
Cc: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Tested-by: Agathe Porte <agathe.porte@nokia.com>
Link: https://lore.kernel.org/r/20220222223610.23098-2-linux@roeck-us.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-03-03 07:40:42 -08:00

713 lines
18 KiB
C

// 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, &regval);
if (err < 0)
break;
*val = !!(regval & BIT(channel + 7));
break;
case hwmon_temp_crit_alarm:
err = regmap_read(regmap, TMP464_THERM2_STATUS_REG, &regval);
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, &regval);
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], &regval);
if (err < 0)
break;
err = regmap_read(regmap, TMP464_TEMP_HYST_REG, &regval2);
if (err < 0)
break;
regval -= regval2;
*val = temp_from_reg(regval);
break;
case hwmon_temp_max:
err = regmap_read(regmap, TMP464_THERM_LIMIT[channel], &regval);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_crit_hyst:
err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], &regval);
if (err < 0)
break;
err = regmap_read(regmap, TMP464_TEMP_HYST_REG, &regval2);
if (err < 0)
break;
regval -= regval2;
*val = temp_from_reg(regval);
break;
case hwmon_temp_crit:
err = regmap_read(regmap, TMP464_THERM2_LIMIT[channel], &regval);
if (err < 0)
break;
*val = temp_from_reg(regval);
break;
case hwmon_temp_offset:
err = regmap_read(regmap, TMP464_TEMP_OFFSET_REG(channel), &regval);
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), &regval);
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], &regval);
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, &regval);
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, &regval);
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");