MAX31730 is a 3-Channel Remote Temperature Sensor. Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- This patch needs to be applied on top of https://patchwork.kernel.org/patch/11277603/ Documentation/hwmon/index.rst | 1 + Documentation/hwmon/max31730.rst | 44 ++++ drivers/hwmon/Kconfig | 12 +- drivers/hwmon/Makefile | 1 + drivers/hwmon/max31730.c | 440 +++++++++++++++++++++++++++++++ 5 files changed, 497 insertions(+), 1 deletion(-) create mode 100644 Documentation/hwmon/max31730.rst create mode 100644 drivers/hwmon/max31730.c diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 43cc605741ea..b91da3acccb9 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -108,6 +108,7 @@ Hardware Monitoring Kernel Drivers max197 max20751 max31722 + max31730 max31785 max31790 max34440 diff --git a/Documentation/hwmon/max31730.rst b/Documentation/hwmon/max31730.rst new file mode 100644 index 000000000000..def0de19dbd2 --- /dev/null +++ b/Documentation/hwmon/max31730.rst @@ -0,0 +1,44 @@ +Kernel driver max31790 +====================== + +Supported chips: + + * Maxim MAX31730 + + Prefix: 'max31730' + + Addresses scanned: 0x1c, 0x1d, 0x1e, 0x1f, 0x4c, 0x4d, 0x4e, 0x4f + + Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX31730.pdf + +Author: Guenter Roeck <linux@xxxxxxxxxxxx> + + +Description +----------- + +This driver implements support for Maxim MAX31730. + +The MAX31730 temperature sensor monitors its own temperature and the +temperatures of three external diode-connected transistors. The operating +supply voltage is from 3.0V to 3.6V. Resistance cancellation compensates +for high series resistance in circuit-board traces and the external thermal +diode, while beta compensation corrects for temperature-measurement +errors due to low-beta sensing transistors. + + +Sysfs entries +------------- + +=================== == ======================================================= +temp[1-4]_enable RW Temperature enable/disable + Set to 0 to enable channel, 0 to disable +temp[1-4]_input RO Temperature input +temp[2-4]_fault RO Fault indicator for remote channels +temp[1-4]_max RW Maximum temperature +temp[1-4]_max_alarm RW Maximum temperature alarm +temp[1-4]_min RW Minimum temperature. Common for all channels. + Only temp1_min is writeable. +temp[1-4]_min_alarm RO Minimum temperature alarm +temp[2-4]_offset RW Temperature offset for remote channels +=================== == ======================================================= diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 23dfe848979a..54e1b9cbc0b9 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -889,7 +889,7 @@ config SENSORS_MAX197 will be called max197. config SENSORS_MAX31722 -tristate "MAX31722 temperature sensor" + tristate "MAX31722 temperature sensor" depends on SPI help Support for the Maxim Integrated MAX31722/MAX31723 digital @@ -898,6 +898,16 @@ tristate "MAX31722 temperature sensor" This driver can also be built as a module. If so, the module will be called max31722. +config SENSORS_MAX31730 + tristate "MAX31730 temperature sensor" + depends on I2C + help + Support for the Maxim Integrated MAX31730 3-Channel Remote + Temperature Sensor. + + This driver can also be built as a module. If so, the module + will be called max31730. + config SENSORS_MAX6621 tristate "Maxim MAX6621 sensor chip" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 6db5db9cdc29..226a1182967a 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -123,6 +123,7 @@ obj-$(CONFIG_SENSORS_MAX1619) += max1619.o obj-$(CONFIG_SENSORS_MAX1668) += max1668.o obj-$(CONFIG_SENSORS_MAX197) += max197.o obj-$(CONFIG_SENSORS_MAX31722) += max31722.o +obj-$(CONFIG_SENSORS_MAX31730) += max31730.o obj-$(CONFIG_SENSORS_MAX6621) += max6621.o obj-$(CONFIG_SENSORS_MAX6639) += max6639.o obj-$(CONFIG_SENSORS_MAX6642) += max6642.o diff --git a/drivers/hwmon/max31730.c b/drivers/hwmon/max31730.c new file mode 100644 index 000000000000..eb22a34dc36b --- /dev/null +++ b/drivers/hwmon/max31730.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for MAX31730 3-Channel Remote Temperature Sensor + * + * Copyright (c) 2019 Guenter Roeck <linux@xxxxxxxxxxxx> + */ + +#include <linux/bits.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/hwmon.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/slab.h> + +/* Addresses scanned */ +static const unsigned short normal_i2c[] = { 0x1c, 0x1d, 0x1e, 0x1f, 0x4c, + 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; + +/* The MAX31730 registers */ +#define MAX31730_REG_TEMP 0x00 +#define MAX31730_REG_CONF 0x13 +#define MAX31730_STOP BIT(7) +#define MAX31730_EXTRANGE BIT(1) +#define MAX31730_REG_TEMP_OFFSET 0x16 +#define MAX31730_TEMP_OFFSET_BASELINE 0x77 +#define MAX31730_REG_OFFSET_ENABLE 0x17 +#define MAX31730_REG_TEMP_MAX 0x20 +#define MAX31730_REG_TEMP_MIN 0x30 +#define MAX31730_REG_STATUS_HIGH 0x32 +#define MAX31730_REG_STATUS_LOW 0x33 +#define MAX31730_REG_CHANNEL_ENABLE 0x35 +#define MAX31730_REG_TEMP_FAULT 0x36 + +#define MAX31730_REG_MFG_ID 0x50 +#define MAX31730_MFG_ID 0x4d +#define MAX31730_REG_MFG_REV 0x51 +#define MAX31730_MFG_REV 0x01 + +#define MAX31730_TEMP_MIN (-128000) +#define MAX31730_TEMP_MAX 127937 + +/* Each client has this additional data */ +struct max31730_data { + struct i2c_client *client; + u8 orig_conf; + u8 current_conf; + u8 offset_enable; + u8 channel_enable; +}; + +/*-----------------------------------------------------------------------*/ + +static inline long max31730_reg_to_mc(s16 temp) +{ + return DIV_ROUND_CLOSEST((temp >> 4) * 1000, 16); +} + +static int max31730_write_config(struct max31730_data *data, u8 set_mask, + u8 clr_mask) +{ + u8 value; + + clr_mask |= MAX31730_EXTRANGE; + value = data->current_conf & ~clr_mask; + value |= set_mask; + + if (data->current_conf != value) { + s32 err; + + err = i2c_smbus_write_byte_data(data->client, MAX31730_REG_CONF, + value); + if (err) + return err; + data->current_conf = value; + } + return 0; +} + +static int max31730_set_enable(struct i2c_client *client, int reg, + u8 *confdata, int channel, bool enable) +{ + u8 regval = *confdata; + int err; + + if (enable) + regval |= BIT(channel); + else + regval &= ~BIT(channel); + + if (regval != *confdata) { + err = i2c_smbus_write_byte_data(client, reg, regval); + if (err) + return err; + *confdata = regval; + } + return 0; +} + +static int max31730_set_offset_enable(struct max31730_data *data, int channel, + bool enable) +{ + return max31730_set_enable(data->client, MAX31730_REG_OFFSET_ENABLE, + &data->offset_enable, channel, enable); +} + +static int max31730_set_channel_enable(struct max31730_data *data, int channel, + bool enable) +{ + return max31730_set_enable(data->client, MAX31730_REG_CHANNEL_ENABLE, + &data->channel_enable, channel, enable); +} + +static int max31730_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct max31730_data *data = dev_get_drvdata(dev); + int regval, reg, offset; + + if (type != hwmon_temp) + return -EINVAL; + + switch (attr) { + case hwmon_temp_input: + if (!(data->channel_enable & BIT(channel))) + return -ENODATA; + reg = MAX31730_REG_TEMP + (channel * 2); + break; + case hwmon_temp_max: + reg = MAX31730_REG_TEMP_MAX + (channel * 2); + break; + case hwmon_temp_min: + reg = MAX31730_REG_TEMP_MIN; + break; + case hwmon_temp_enable: + *val = !!(data->channel_enable & BIT(channel)); + return 0; + case hwmon_temp_offset: + if (!channel) + return -EINVAL; + if (!(data->offset_enable & BIT(channel))) { + *val = 0; + return 0; + } + offset = i2c_smbus_read_byte_data(data->client, + MAX31730_REG_TEMP_OFFSET); + if (offset < 0) + return offset; + *val = (offset - MAX31730_TEMP_OFFSET_BASELINE) * 125; + return 0; + case hwmon_temp_fault: + regval = i2c_smbus_read_byte_data(data->client, + MAX31730_REG_TEMP_FAULT); + if (regval < 0) + return regval; + *val = !!(regval & BIT(channel)); + return 0; + case hwmon_temp_min_alarm: + regval = i2c_smbus_read_byte_data(data->client, + MAX31730_REG_STATUS_LOW); + if (regval < 0) + return regval; + *val = !!(regval & BIT(channel)); + return 0; + case hwmon_temp_max_alarm: + regval = i2c_smbus_read_byte_data(data->client, + MAX31730_REG_STATUS_HIGH); + if (regval < 0) + return regval; + *val = !!(regval & BIT(channel)); + return 0; + default: + return -EINVAL; + } + regval = i2c_smbus_read_word_swapped(data->client, reg); + if (regval < 0) + return regval; + + *val = max31730_reg_to_mc(regval); + + return 0; +} + +static int max31730_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + struct max31730_data *data = dev_get_drvdata(dev); + int reg, err; + + if (type != hwmon_temp) + return -EINVAL; + + switch (attr) { + case hwmon_temp_max: + reg = MAX31730_REG_TEMP_MAX + channel * 2; + break; + case hwmon_temp_min: + reg = MAX31730_REG_TEMP_MIN; + break; + case hwmon_temp_enable: + if (val != 0 && val != 1) + return -EINVAL; + return max31730_set_channel_enable(data, channel, val); + case hwmon_temp_offset: + val = clamp_val(val, -14875, 17000) + 14875; + val = DIV_ROUND_CLOSEST(val, 125); + err = max31730_set_offset_enable(data, channel, + val != MAX31730_TEMP_OFFSET_BASELINE); + if (err) + return err; + return i2c_smbus_write_byte_data(data->client, + MAX31730_REG_TEMP_OFFSET, val); + default: + return -EINVAL; + } + + val = clamp_val(val, MAX31730_TEMP_MIN, MAX31730_TEMP_MAX); + val = DIV_ROUND_CLOSEST(val << 4, 1000) << 4; + + return i2c_smbus_write_word_swapped(data->client, reg, (u16)val); +} + +static umode_t max31730_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_min_alarm: + case hwmon_temp_max_alarm: + case hwmon_temp_fault: + return 0444; + case hwmon_temp_min: + return channel ? 0444 : 0644; + case hwmon_temp_offset: + case hwmon_temp_enable: + case hwmon_temp_max: + return 0644; + } + break; + default: + break; + } + return 0; +} + +static const struct hwmon_channel_info *max31730_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_ENABLE | + HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM, + HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_OFFSET | HWMON_T_ENABLE | + HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | + HWMON_T_FAULT, + HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_OFFSET | HWMON_T_ENABLE | + HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | + HWMON_T_FAULT, + HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_OFFSET | HWMON_T_ENABLE | + HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | + HWMON_T_FAULT + ), + NULL +}; + +static const struct hwmon_ops max31730_hwmon_ops = { + .is_visible = max31730_is_visible, + .read = max31730_read, + .write = max31730_write, +}; + +static const struct hwmon_chip_info max31730_chip_info = { + .ops = &max31730_hwmon_ops, + .info = max31730_info, +}; + +static void max31730_remove(void *data) +{ + struct max31730_data *max31730 = data; + struct i2c_client *client = max31730->client; + + i2c_smbus_write_byte_data(client, MAX31730_REG_CONF, + max31730->orig_conf); +} + +static int +max31730_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + struct max31730_data *data; + int status, err; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) + return -EIO; + + data = devm_kzalloc(dev, sizeof(struct max31730_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + + /* Cache original configuration and enable status */ + status = i2c_smbus_read_byte_data(client, MAX31730_REG_CHANNEL_ENABLE); + if (status < 0) + return status; + data->channel_enable = status; + + status = i2c_smbus_read_byte_data(client, MAX31730_REG_OFFSET_ENABLE); + if (status < 0) + return status; + data->offset_enable = status; + + status = i2c_smbus_read_byte_data(client, MAX31730_REG_CONF); + if (status < 0) + return status; + data->orig_conf = status; + data->current_conf = status; + + err = max31730_write_config(data, + data->channel_enable ? 0 : MAX31730_STOP, + data->channel_enable ? MAX31730_STOP : 0); + if (err) + return err; + + dev_set_drvdata(dev, data); + + err = devm_add_action_or_reset(dev, max31730_remove, data); + if (err) + return err; + + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, + data, + &max31730_chip_info, + NULL); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id max31730_ids[] = { + { "max31730", 0, }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max31730_ids); + +static const struct of_device_id __maybe_unused max31730_of_match[] = { + { + .compatible = "maxim,max31730", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, max31730_of_match); + +static bool max31730_check_reg_temp(struct i2c_client *client, + int reg) +{ + int regval; + + regval = i2c_smbus_read_byte_data(client, reg + 1); + return regval < 0 || (regval & 0x0f); +} + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int max31730_detect(struct i2c_client *client, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = client->adapter; + int regval; + int i; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + regval = i2c_smbus_read_byte_data(client, MAX31730_REG_MFG_ID); + if (regval != MAX31730_MFG_ID) + return -ENODEV; + regval = i2c_smbus_read_byte_data(client, MAX31730_REG_MFG_REV); + if (regval != MAX31730_MFG_REV) + return -ENODEV; + + /* lower 4 bit of temperature and limit registers must be 0 */ + if (max31730_check_reg_temp(client, MAX31730_REG_TEMP_MIN)) + return -ENODEV; + + for (i = 0; i < 4; i++) { + if (max31730_check_reg_temp(client, MAX31730_REG_TEMP + i * 2)) + return -ENODEV; + if (max31730_check_reg_temp(client, + MAX31730_REG_TEMP_MAX + i * 2)) + return -ENODEV; + } + + strlcpy(info->type, "max31730", I2C_NAME_SIZE); + + return 0; +} + +static int __maybe_unused max31730_suspend(struct device *dev) +{ + struct max31730_data *data = dev_get_drvdata(dev); + + return max31730_write_config(data, MAX31730_STOP, 0); +} + +static int __maybe_unused max31730_resume(struct device *dev) +{ + struct max31730_data *data = dev_get_drvdata(dev); + + return max31730_write_config(data, 0, MAX31730_STOP); +} + +static SIMPLE_DEV_PM_OPS(max31730_pm_ops, max31730_suspend, max31730_resume); + +static struct i2c_driver max31730_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "max31730", + .of_match_table = of_match_ptr(max31730_of_match), + .pm = &max31730_pm_ops, + }, + .probe = max31730_probe, + .id_table = max31730_ids, + .detect = max31730_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(max31730_driver); + +MODULE_AUTHOR("Guenter Roeck <linux@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("MAX31730 driver"); +MODULE_LICENSE("GPL"); -- 2.17.1
