diff options
Diffstat (limited to 'drivers/hwmon/tmp464.c')
| -rw-r--r-- | drivers/hwmon/tmp464.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/drivers/hwmon/tmp464.c b/drivers/hwmon/tmp464.c new file mode 100644 index 0000000000..f58ca4c6ac --- /dev/null +++ b/drivers/hwmon/tmp464.c @@ -0,0 +1,712 @@ +// 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.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 * const 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_MAPLE, + .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 = 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"); |