| Message ID | 20250123202528.223966-2-andrey.lalaev@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add driver for HTU31 | expand |
On Thu, Jan 23, 2025 at 09:25:06PM +0100, Andrei Lalaev wrote: > ibmpowernv > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 4cbaba15d86e..e123e06ba352 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -789,6 +789,17 @@ config SENSORS_HS3001 > This driver can also be built as a module. If so, the module > will be called hs3001. > Looks like you add here stray spaces. > +config SENSORS_HTU31 > + tristate "Measurement Specialties HTU31 humidity and temperature sensor" > + depends on I2C > + select CRC8 > + help > + If you say yes here you get support for the HTU31 humidity > + and temperature sensors. > + > + This driver can also be built as a module. If so, the module > + will be called htu31. > + > config SENSORS_IBMAEM > tristate "IBM Active Energy Manager temperature/power sensors and control" > select IPMI_SI > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index b7ef0f0562d3..02465d959d14 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -199,6 +199,7 @@ obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o > obj-$(CONFIG_SENSORS_SFCTEMP) += sfctemp.o > obj-$(CONFIG_SENSORS_SG2042_MCU) += sg2042-mcu.o > obj-$(CONFIG_SENSORS_SL28CPLD) += sl28cpld-hwmon.o > +obj-$(CONFIG_SENSORS_HTU31) += htu31.o > obj-$(CONFIG_SENSORS_SHT15) += sht15.o > obj-$(CONFIG_SENSORS_SHT21) += sht21.o > obj-$(CONFIG_SENSORS_SHT3x) += sht3x.o > diff --git a/drivers/hwmon/htu31.c b/drivers/hwmon/htu31.c > new file mode 100644 > index 000000000000..09f979a8db92 > --- /dev/null > +++ b/drivers/hwmon/htu31.c > @@ -0,0 +1,335 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * The driver for Measurement Specialties HTU31 Temperature and Humidity sensor. > + * > + * Copyright (C) 2025 > + * Author: Andrei Lalaev <andrey.lalaev@gmail.com> > + */ > + > +#include <linux/array_size.h> > +#include <linux/cleanup.h> > +#include <linux/crc8.h> > +#include <linux/delay.h> > +#include <linux/hwmon.h> > +#include <linux/hwmon-sysfs.h> > +#include <linux/i2c.h> > +#include <linux/init.h> > +#include <linux/module.h> > + > +#define HTU31_READ_TEMP_HUM_CMD 0x00 > +#define HTU31_READ_SERIAL_CMD 0x0a > +#define HTU31_CONVERSION_CMD 0x5e > +#define HTU31_HEATER_OFF_CMD 0x02 > +#define HTU31_HEATER_ON_CMD 0x04 > + > +#define HTU31_TEMP_HUM_LEN 6 > + > +/* Conversion time for the highest resolution */ > +#define HTU31_HUMIDITY_CONV_TIME 10000 /* us */ > +#define HTU31_TEMPERATURE_CONV_TIME 15000 /* us */ > + > +#define HTU31_SERIAL_NUMBER_LEN 3 > +#define HTU31_SERIAL_NUMBER_CRC_LEN 1 > +#define HTU31_SERIAL_NUMBER_CRC_OFFSET 3 > + > +#define HTU31_CRC8_INIT_VAL 0 > +#define HTU31_CRC8_POLYNOMIAL 0x31 > +DECLARE_CRC8_TABLE(htu31_crc8_table); > + > +struct htu31_data { > + struct i2c_client *client; > + struct mutex i2c_lock; What is the lock guarding? See checkpatch below. What's confusing is that you call it I2C but it also covers some memcpy operations and this rtcuture, so much wider scope. Be detaile when fixing checkpatch warning. Please run scripts/checkpatch.pl and fix reported warnings. After that, run also 'scripts/checkpatch.pl --strict' and (probably) fix more warnings. Some warnings can be ignored, especially from --strict run, but the code here looks like it needs a fix. Feel free to get in touch if the warning is not clear. > + long wait_time; > + long temperature; > + long humidity; > + u8 serial_number[HTU31_SERIAL_NUMBER_LEN]; > + bool heater_enable; > +}; > + > +static long htu31_temp_to_millicelsius(long val) > +{ > + return -40000 + DIV_ROUND_CLOSEST(165000 * val, 65535); > +} > + > +static long htu31_relative_humidity(long val) > +{ > + return DIV_ROUND_CLOSEST(100000 * val, 65535); > +} > + > +static int htu31_data_fetch_command(struct htu31_data *data) > +{ > + struct i2c_client *client = data->client; > + u8 conversion_on = HTU31_CONVERSION_CMD; > + u8 read_data_cmd = HTU31_READ_TEMP_HUM_CMD; > + u8 t_h_buf[HTU31_TEMP_HUM_LEN] = {}; > + struct i2c_msg msgs[] = { > + { > + .addr = client->addr, > + .flags = 0, > + .len = 1, > + .buf = &read_data_cmd, > + }, > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = sizeof(t_h_buf), > + .buf = t_h_buf, > + }, > + }; > + int ret; > + u8 crc; > + > + guard(mutex)(&data->i2c_lock); > + > + ret = i2c_master_send(client, &conversion_on, 1); > + if (ret != 1) { > + ret = ret < 0 ? ret : -EIO; > + dev_err(&client->dev, > + "Conversion command is failed. Error code: %d\n", ret); > + return ret; > + } > + > + fsleep(data->wait_time); > + > + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); > + if (ret != ARRAY_SIZE(msgs)) { > + ret = ret < 0 ? ret : -EIO; > + dev_err(&client->dev, > + "T&H command is failed. Error code: %d\n", ret); > + return ret; > + } > + > + crc = crc8(htu31_crc8_table, &t_h_buf[0], 2, HTU31_CRC8_INIT_VAL); > + if (crc != t_h_buf[2]) { > + dev_err(&client->dev, "Temperature CRC mismatch\n"); > + return -EIO; > + } > + > + crc = crc8(htu31_crc8_table, &t_h_buf[3], 2, HTU31_CRC8_INIT_VAL); > + if (crc != t_h_buf[5]) { > + dev_err(&client->dev, "Humidity CRC mismatch\n"); > + return -EIO; > + } > + > + data->temperature = htu31_temp_to_millicelsius(be16_to_cpup((__be16 *) &t_h_buf[0])); > + data->humidity = htu31_relative_humidity(be16_to_cpup((__be16 *) &t_h_buf[3])); > + > + return 0; > +} > + > +static umode_t htu31_is_visible(const void *data, enum hwmon_sensor_types type, > + u32 attr, int channel) > +{ > + switch (type) { > + case hwmon_temp: > + case hwmon_humidity: > + return 0444; > + default: > + return 0; > + } > +} > + > +static int htu31_read(struct device *dev, enum hwmon_sensor_types type, > + u32 attr, int channel, long *val) > +{ > + struct htu31_data *data = dev_get_drvdata(dev); > + int ret; > + > + ret = htu31_data_fetch_command(data); > + > + if (ret < 0) > + return ret; > + > + switch (type) { > + case hwmon_temp: > + if (attr != hwmon_temp_input) > + return -EINVAL; > + > + *val = data->temperature; > + break; > + case hwmon_humidity: > + if (attr != hwmon_humidity_input) > + return -EINVAL; > + > + *val = data->humidity; > + break; > + default: > + return -EOPNOTSUPP; > + } > + > + return 0; > +} > + > +static int serial_number_populate(struct htu31_data *data) htu31_read_serial_number(...) > +{ > + struct i2c_client *client = data->client; > + u8 read_sn_cmd = HTU31_READ_SERIAL_CMD; > + u8 sn_buf[HTU31_SERIAL_NUMBER_LEN + HTU31_SERIAL_NUMBER_CRC_LEN]; > + struct i2c_msg msgs[] = { > + { > + .addr = client->addr, > + .flags = 0, > + .len = 1, > + .buf = &read_sn_cmd, > + }, > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = sizeof(sn_buf), > + .buf = sn_buf, > + }, > + }; > + int ret; > + u8 crc; > + > + guard(mutex)(&data->i2c_lock); > + > + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); > + if (ret < 0) > + return -EIO; > + > + crc = crc8(htu31_crc8_table, sn_buf, HTU31_SERIAL_NUMBER_LEN, HTU31_CRC8_INIT_VAL); > + if (crc != sn_buf[HTU31_SERIAL_NUMBER_CRC_OFFSET]) { > + dev_err(&client->dev, "Serial number CRC mismatch\n"); > + return -EIO; > + } > + > + memcpy(data->serial_number, sn_buf, HTU31_SERIAL_NUMBER_LEN); ... > +#if IS_ENABLED(CONFIG_OF) > +static const struct of_device_id htu31_of_match[] = { > + { .compatible = "meas,htu31" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, htu31_of_match); > +#endif > + > +static struct i2c_driver htu31_driver = { > + .driver = { > + .name = "htu31", > + .of_match_table = of_match_ptr(htu31_of_match), > + }, > + .probe = htu31_probe, > + .id_table = htu31_id, > +}; > +module_i2c_driver(htu31_driver); > + > +MODULE_AUTHOR("Andrei Lalaev <andrey.lalaev@gmail.com>"); > +MODULE_DESCRIPTION("HTU31 Temperature and Humidity sensor driver"); > +MODULE_VERSION("1.0"); Drop version. Linux kernel defines the version. Best regards, Krzysztof
Le 23/01/2025 à 21:25, Andrei Lalaev a écrit : > Add base support for HTU31 temperature and humidity sensor. > > Besides temperature and humidity values, the driver also exports a 24-bit > serial number to sysfs. > > Signed-off-by: Andrei Lalaev <andrey.lalaev@gmail.com> > --- ... > +static int htu31_read(struct device *dev, enum hwmon_sensor_types type, > + u32 attr, int channel, long *val) > +{ > + struct htu31_data *data = dev_get_drvdata(dev); > + int ret; > + > + ret = htu31_data_fetch_command(data); > + Unneeded empty line. > + if (ret < 0) > + return ret; > + > + switch (type) { > + case hwmon_temp: > + if (attr != hwmon_temp_input) > + return -EINVAL; > + > + *val = data->temperature; > + break; > + case hwmon_humidity: > + if (attr != hwmon_humidity_input) > + return -EINVAL; > + > + *val = data->humidity; > + break; > + default: > + return -EOPNOTSUPP; > + } > + > + return 0; > +} > + > +static int serial_number_populate(struct htu31_data *data) > +{ > + struct i2c_client *client = data->client; > + u8 read_sn_cmd = HTU31_READ_SERIAL_CMD; > + u8 sn_buf[HTU31_SERIAL_NUMBER_LEN + HTU31_SERIAL_NUMBER_CRC_LEN]; > + struct i2c_msg msgs[] = { > + { > + .addr = client->addr, > + .flags = 0, > + .len = 1, > + .buf = &read_sn_cmd, > + }, > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = sizeof(sn_buf), > + .buf = sn_buf, > + }, > + }; > + int ret; > + u8 crc; > + > + guard(mutex)(&data->i2c_lock); > + > + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); > + if (ret < 0) > + return -EIO; Why not return ret? > + > + crc = crc8(htu31_crc8_table, sn_buf, HTU31_SERIAL_NUMBER_LEN, HTU31_CRC8_INIT_VAL); > + if (crc != sn_buf[HTU31_SERIAL_NUMBER_CRC_OFFSET]) { > + dev_err(&client->dev, "Serial number CRC mismatch\n"); > + return -EIO; > + } > + > + memcpy(data->serial_number, sn_buf, HTU31_SERIAL_NUMBER_LEN); > + > + return 0; > +} ... > +static ssize_t heater_enable_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, > + size_t count) > +{ > + struct htu31_data *data = dev_get_drvdata(dev); > + u8 heater_cmd; > + bool status; > + int ret; > + > + ret = kstrtobool(buf, &status); > + if (ret) > + return ret; > + > + heater_cmd = status ? HTU31_HEATER_ON_CMD : HTU31_HEATER_OFF_CMD; > + > + guard(mutex)(&data->i2c_lock); > + > + ret = i2c_master_send(data->client, &heater_cmd, 1); > + if (ret < 0) > + return -EIO; Why not return ret? > + > + data->heater_enable = status; > + > + return count; > +} > + > +static DEVICE_ATTR_RW(heater_enable); > + > +static ssize_t serial_number_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct htu31_data *data = dev_get_drvdata(dev); > + > + return sysfs_emit(buf, "%X%X%X\n", data->serial_number[0], > + data->serial_number[1], > + data->serial_number[2]); > +} > + > +static DEVICE_ATTR_RO(serial_number); > + > +static struct attribute *htu31_attrs[] = { > + &dev_attr_heater_enable.attr, > + &dev_attr_serial_number.attr, > + NULL, No need for trailing comma after a terminator > +}; > + > +ATTRIBUTE_GROUPS(htu31); > + > +static const struct hwmon_channel_info * const htu31_info[] = { > + HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT), > + HWMON_CHANNEL_INFO(humidity, HWMON_H_INPUT), > + NULL, No need for trailing comma after a terminator > +}; ... > +static int htu31_probe(struct i2c_client *client) > +{ > + struct device *dev = &client->dev; > + struct device *hwmon_dev; > + struct htu31_data *data; > + > + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->client = client; > + data->wait_time = HTU31_TEMPERATURE_CONV_TIME + HTU31_HUMIDITY_CONV_TIME; > + > + mutex_init(&data->i2c_lock); Maybe devm_mutex_init()? > + > + crc8_populate_msb(htu31_crc8_table, HTU31_CRC8_POLYNOMIAL); > + > + if (serial_number_populate(data)) { Maybe: ret = serial_number_populate(data); if (ret) { ... return ret; } > + dev_err(dev, "Failed to read serial number\n"); > + return -EIO; > + } > + > + hwmon_dev = devm_hwmon_device_register_with_info(dev, > + client->name, > + data, > + &htu31_chip_info, > + htu31_groups); > + > + return PTR_ERR_OR_ZERO(hwmon_dev); > +} > + > +static const struct i2c_device_id htu31_id[] = { > + { "htu31" }, > + { }, No need for trailing comma after a terminator > +}; > +MODULE_DEVICE_TABLE(i2c, htu31_id); > + > +#if IS_ENABLED(CONFIG_OF) > +static const struct of_device_id htu31_of_match[] = { > + { .compatible = "meas,htu31" }, > + { }, No need for trailing comma after a terminator > +}; > +MODULE_DEVICE_TABLE(of, htu31_of_match); ... CJ
On 24.01.2025 09:31, Krzysztof Kozlowski wrote: > On Thu, Jan 23, 2025 at 09:25:06PM +0100, Andrei Lalaev wrote: >> ibmpowernv >> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig >> index 4cbaba15d86e..e123e06ba352 100644 >> --- a/drivers/hwmon/Kconfig >> +++ b/drivers/hwmon/Kconfig >> @@ -789,6 +789,17 @@ config SENSORS_HS3001 >> This driver can also be built as a module. If so, the module >> will be called hs3001. >> > > Looks like you add here stray spaces. > Could you please explain what you mean? I see only 1 tab and 2 spaces right after it, but they were here even before my patch.
On 24/01/2025 15:56, Andrei Lalaev wrote: > On 24.01.2025 09:31, Krzysztof Kozlowski wrote: >> On Thu, Jan 23, 2025 at 09:25:06PM +0100, Andrei Lalaev wrote: >>> ibmpowernv >>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig >>> index 4cbaba15d86e..e123e06ba352 100644 >>> --- a/drivers/hwmon/Kconfig >>> +++ b/drivers/hwmon/Kconfig >>> @@ -789,6 +789,17 @@ config SENSORS_HS3001 >>> This driver can also be built as a module. If so, the module >>> will be called hs3001. >>> >> >> Looks like you add here stray spaces. >> > > Could you please explain what you mean? I see only 1 tab and 2 spaces right after it, > but they were here even before my patch. Diff in mutt looked like having stray spaces added in this hunk. Exactly that line I commented under, not in some other place. There was no tab and 2 spaces. If you double checked and are sure there is no stray space, then fine. Could be just mutt.... Best regards, Krzysztof
diff --git a/Documentation/hwmon/htu31.rst b/Documentation/hwmon/htu31.rst new file mode 100644 index 000000000000..a7a960e215ec --- /dev/null +++ b/Documentation/hwmon/htu31.rst @@ -0,0 +1,38 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +Kernel driver HTU31 +==================== + +Supported chips: + + * Measurement Specialties HTU31 + + Prefix: 'htu31' + + Addresses scanned: - + + Datasheet: Publicly available from https://www.te.com/en/product-CAT-HSC0007.html + +Author: + + - Andrei Lalaev <andrey.lalaev@gmail.com> + +Description +----------- + +HTU31 is a humidity and temperature sensor. + +Supported temperature range is from -40 to 125 degrees Celsius. + +Communication with the device is performed via I2C protocol. Sensor's default address +is 0x40. + +sysfs-Interface +--------------- + +=================== ================= +temp1_input: temperature input +humidity1_input: humidity input +serial_number: serial number +heater_enable: heater control +=================== ================= diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 874f8fd26325..86f6f5e46b59 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -85,6 +85,7 @@ Hardware Monitoring Kernel Drivers hih6130 hp-wmi-sensors hs3001 + htu31 ibmaem ibm-cffps ibmpowernv diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 4cbaba15d86e..e123e06ba352 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -789,6 +789,17 @@ config SENSORS_HS3001 This driver can also be built as a module. If so, the module will be called hs3001. +config SENSORS_HTU31 + tristate "Measurement Specialties HTU31 humidity and temperature sensor" + depends on I2C + select CRC8 + help + If you say yes here you get support for the HTU31 humidity + and temperature sensors. + + This driver can also be built as a module. If so, the module + will be called htu31. + config SENSORS_IBMAEM tristate "IBM Active Energy Manager temperature/power sensors and control" select IPMI_SI diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index b7ef0f0562d3..02465d959d14 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -199,6 +199,7 @@ obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o obj-$(CONFIG_SENSORS_SFCTEMP) += sfctemp.o obj-$(CONFIG_SENSORS_SG2042_MCU) += sg2042-mcu.o obj-$(CONFIG_SENSORS_SL28CPLD) += sl28cpld-hwmon.o +obj-$(CONFIG_SENSORS_HTU31) += htu31.o obj-$(CONFIG_SENSORS_SHT15) += sht15.o obj-$(CONFIG_SENSORS_SHT21) += sht21.o obj-$(CONFIG_SENSORS_SHT3x) += sht3x.o diff --git a/drivers/hwmon/htu31.c b/drivers/hwmon/htu31.c new file mode 100644 index 000000000000..09f979a8db92 --- /dev/null +++ b/drivers/hwmon/htu31.c @@ -0,0 +1,335 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The driver for Measurement Specialties HTU31 Temperature and Humidity sensor. + * + * Copyright (C) 2025 + * Author: Andrei Lalaev <andrey.lalaev@gmail.com> + */ + +#include <linux/array_size.h> +#include <linux/cleanup.h> +#include <linux/crc8.h> +#include <linux/delay.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/module.h> + +#define HTU31_READ_TEMP_HUM_CMD 0x00 +#define HTU31_READ_SERIAL_CMD 0x0a +#define HTU31_CONVERSION_CMD 0x5e +#define HTU31_HEATER_OFF_CMD 0x02 +#define HTU31_HEATER_ON_CMD 0x04 + +#define HTU31_TEMP_HUM_LEN 6 + +/* Conversion time for the highest resolution */ +#define HTU31_HUMIDITY_CONV_TIME 10000 /* us */ +#define HTU31_TEMPERATURE_CONV_TIME 15000 /* us */ + +#define HTU31_SERIAL_NUMBER_LEN 3 +#define HTU31_SERIAL_NUMBER_CRC_LEN 1 +#define HTU31_SERIAL_NUMBER_CRC_OFFSET 3 + +#define HTU31_CRC8_INIT_VAL 0 +#define HTU31_CRC8_POLYNOMIAL 0x31 +DECLARE_CRC8_TABLE(htu31_crc8_table); + +struct htu31_data { + struct i2c_client *client; + struct mutex i2c_lock; + long wait_time; + long temperature; + long humidity; + u8 serial_number[HTU31_SERIAL_NUMBER_LEN]; + bool heater_enable; +}; + +static long htu31_temp_to_millicelsius(long val) +{ + return -40000 + DIV_ROUND_CLOSEST(165000 * val, 65535); +} + +static long htu31_relative_humidity(long val) +{ + return DIV_ROUND_CLOSEST(100000 * val, 65535); +} + +static int htu31_data_fetch_command(struct htu31_data *data) +{ + struct i2c_client *client = data->client; + u8 conversion_on = HTU31_CONVERSION_CMD; + u8 read_data_cmd = HTU31_READ_TEMP_HUM_CMD; + u8 t_h_buf[HTU31_TEMP_HUM_LEN] = {}; + struct i2c_msg msgs[] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &read_data_cmd, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof(t_h_buf), + .buf = t_h_buf, + }, + }; + int ret; + u8 crc; + + guard(mutex)(&data->i2c_lock); + + ret = i2c_master_send(client, &conversion_on, 1); + if (ret != 1) { + ret = ret < 0 ? ret : -EIO; + dev_err(&client->dev, + "Conversion command is failed. Error code: %d\n", ret); + return ret; + } + + fsleep(data->wait_time); + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret != ARRAY_SIZE(msgs)) { + ret = ret < 0 ? ret : -EIO; + dev_err(&client->dev, + "T&H command is failed. Error code: %d\n", ret); + return ret; + } + + crc = crc8(htu31_crc8_table, &t_h_buf[0], 2, HTU31_CRC8_INIT_VAL); + if (crc != t_h_buf[2]) { + dev_err(&client->dev, "Temperature CRC mismatch\n"); + return -EIO; + } + + crc = crc8(htu31_crc8_table, &t_h_buf[3], 2, HTU31_CRC8_INIT_VAL); + if (crc != t_h_buf[5]) { + dev_err(&client->dev, "Humidity CRC mismatch\n"); + return -EIO; + } + + data->temperature = htu31_temp_to_millicelsius(be16_to_cpup((__be16 *) &t_h_buf[0])); + data->humidity = htu31_relative_humidity(be16_to_cpup((__be16 *) &t_h_buf[3])); + + return 0; +} + +static umode_t htu31_is_visible(const void *data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + switch (type) { + case hwmon_temp: + case hwmon_humidity: + return 0444; + default: + return 0; + } +} + +static int htu31_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct htu31_data *data = dev_get_drvdata(dev); + int ret; + + ret = htu31_data_fetch_command(data); + + if (ret < 0) + return ret; + + switch (type) { + case hwmon_temp: + if (attr != hwmon_temp_input) + return -EINVAL; + + *val = data->temperature; + break; + case hwmon_humidity: + if (attr != hwmon_humidity_input) + return -EINVAL; + + *val = data->humidity; + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int serial_number_populate(struct htu31_data *data) +{ + struct i2c_client *client = data->client; + u8 read_sn_cmd = HTU31_READ_SERIAL_CMD; + u8 sn_buf[HTU31_SERIAL_NUMBER_LEN + HTU31_SERIAL_NUMBER_CRC_LEN]; + struct i2c_msg msgs[] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &read_sn_cmd, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof(sn_buf), + .buf = sn_buf, + }, + }; + int ret; + u8 crc; + + guard(mutex)(&data->i2c_lock); + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) + return -EIO; + + crc = crc8(htu31_crc8_table, sn_buf, HTU31_SERIAL_NUMBER_LEN, HTU31_CRC8_INIT_VAL); + if (crc != sn_buf[HTU31_SERIAL_NUMBER_CRC_OFFSET]) { + dev_err(&client->dev, "Serial number CRC mismatch\n"); + return -EIO; + } + + memcpy(data->serial_number, sn_buf, HTU31_SERIAL_NUMBER_LEN); + + return 0; +} + +static ssize_t heater_enable_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct htu31_data *data = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%d\n", data->heater_enable); +} + +static ssize_t heater_enable_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct htu31_data *data = dev_get_drvdata(dev); + u8 heater_cmd; + bool status; + int ret; + + ret = kstrtobool(buf, &status); + if (ret) + return ret; + + heater_cmd = status ? HTU31_HEATER_ON_CMD : HTU31_HEATER_OFF_CMD; + + guard(mutex)(&data->i2c_lock); + + ret = i2c_master_send(data->client, &heater_cmd, 1); + if (ret < 0) + return -EIO; + + data->heater_enable = status; + + return count; +} + +static DEVICE_ATTR_RW(heater_enable); + +static ssize_t serial_number_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct htu31_data *data = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%X%X%X\n", data->serial_number[0], + data->serial_number[1], + data->serial_number[2]); +} + +static DEVICE_ATTR_RO(serial_number); + +static struct attribute *htu31_attrs[] = { + &dev_attr_heater_enable.attr, + &dev_attr_serial_number.attr, + NULL, +}; + +ATTRIBUTE_GROUPS(htu31); + +static const struct hwmon_channel_info * const htu31_info[] = { + HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT), + HWMON_CHANNEL_INFO(humidity, HWMON_H_INPUT), + NULL, +}; + +static const struct hwmon_ops htu31_hwmon_ops = { + .is_visible = htu31_is_visible, + .read = htu31_read, +}; + +static const struct hwmon_chip_info htu31_chip_info = { + .info = htu31_info, + .ops = &htu31_hwmon_ops, +}; + +static int htu31_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + struct htu31_data *data; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + data->wait_time = HTU31_TEMPERATURE_CONV_TIME + HTU31_HUMIDITY_CONV_TIME; + + mutex_init(&data->i2c_lock); + + crc8_populate_msb(htu31_crc8_table, HTU31_CRC8_POLYNOMIAL); + + if (serial_number_populate(data)) { + dev_err(dev, "Failed to read serial number\n"); + return -EIO; + } + + hwmon_dev = devm_hwmon_device_register_with_info(dev, + client->name, + data, + &htu31_chip_info, + htu31_groups); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id htu31_id[] = { + { "htu31" }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, htu31_id); + +#if IS_ENABLED(CONFIG_OF) +static const struct of_device_id htu31_of_match[] = { + { .compatible = "meas,htu31" }, + { }, +}; +MODULE_DEVICE_TABLE(of, htu31_of_match); +#endif + +static struct i2c_driver htu31_driver = { + .driver = { + .name = "htu31", + .of_match_table = of_match_ptr(htu31_of_match), + }, + .probe = htu31_probe, + .id_table = htu31_id, +}; +module_i2c_driver(htu31_driver); + +MODULE_AUTHOR("Andrei Lalaev <andrey.lalaev@gmail.com>"); +MODULE_DESCRIPTION("HTU31 Temperature and Humidity sensor driver"); +MODULE_VERSION("1.0"); +MODULE_LICENSE("GPL");
Add base support for HTU31 temperature and humidity sensor. Besides temperature and humidity values, the driver also exports a 24-bit serial number to sysfs. Signed-off-by: Andrei Lalaev <andrey.lalaev@gmail.com> --- Documentation/hwmon/htu31.rst | 38 ++++ Documentation/hwmon/index.rst | 1 + drivers/hwmon/Kconfig | 11 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/htu31.c | 335 ++++++++++++++++++++++++++++++++++ 5 files changed, 386 insertions(+) create mode 100644 Documentation/hwmon/htu31.rst create mode 100644 drivers/hwmon/htu31.c