diff options
| -rw-r--r-- | Documentation/hwmon/sht3x | 72 | ||||
| -rw-r--r-- | drivers/hwmon/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/hwmon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/hwmon/sht3x.c | 725 | ||||
| -rw-r--r-- | include/linux/platform_data/sht3x.h | 25 |
5 files changed, 834 insertions, 0 deletions
diff --git a/Documentation/hwmon/sht3x b/Documentation/hwmon/sht3x new file mode 100644 index 0000000..f5aa633 --- /dev/null +++ b/Documentation/hwmon/sht3x @@ -0,0 +1,72 @@ +Kernel driver sht3x +=================== + +Supported chips: + * Sensirion SHT3x-DIS + Prefix: 'sht3x' + Addresses scanned: none + Datasheet: http://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/Humidity/Sensirion_Humidity_Datasheet_SHT3x_DIS.pdf + +Author: + David Frey <david.frey@sensirion.com> + Pascal Sachs <pascal.sachs@sensirion.com> + +Description +----------- + +This driver implements support for the Sensirion SHT3x-DIS chip, a humidity +and temperature sensor. Temperature is measured in degrees celsius, relative +humidity is expressed as a percentage. In the sysfs interface, all values are +scaled by 1000, i.e. the value for 31.5 degrees celsius is 31500. + +The device communicates with the I2C protocol. Sensors can have the I2C +addresses 0x44 or 0x45, depending on the wiring. See +Documentation/i2c/instantiating-devices for methods to instantiate the device. + +There are two options configurable by means of sht3x_platform_data: +1. blocking (pull the I2C clock line down while performing the measurement) or + non-blocking mode. Blocking mode will guarantee the fastest result but + the I2C bus will be busy during that time. By default, non-blocking mode + is used. Make sure clock-stretching works properly on your device if you + want to use blocking mode. +2. high or low accuracy. High accuracy is used by default and using it is + strongly recommended. + +The sht3x sensor supports a single shot mode as well as 5 periodic measure +modes, which can be controlled with the update_interval sysfs interface. +The allowed update_interval in milliseconds are as follows: + * 0 single shot mode + * 2000 0.5 Hz periodic measurement + * 1000 1 Hz periodic measurement + * 500 2 Hz periodic measurement + * 250 4 Hz periodic measurement + * 100 10 Hz periodic measurement + +In the periodic measure mode, the sensor automatically triggers a measurement +with the configured update interval on the chip. When a temperature or humidity +reading exceeds the configured limits, the alert attribute is set to 1 and +the alert pin on the sensor is set to high. +When the temperature and humidity readings move back between the hysteresis +values, the alert bit is set to 0 and the alert pin on the sensor is set to +low. + +sysfs-Interface +--------------- + +temp1_input: temperature input +humidity1_input: humidity input +temp1_max: temperature max value +temp1_max_hyst: temperature hysteresis value for max limit +humidity1_max: humidity max value +humidity1_max_hyst: humidity hysteresis value for max limit +temp1_min: temperature min value +temp1_min_hyst: temperature hysteresis value for min limit +humidity1_min: humidity min value +humidity1_min_hyst: humidity hysteresis value for min limit +temp1_alarm: alarm flag is set to 1 if the temperature is outside the + configured limits. Alarm only works in periodic measure mode +humidity1_alarm: alarm flag is set to 1 if the humidity is outside the + configured limits. Alarm only works in periodic measure mode +update_interval: update interval, 0 for single shot, interval in msec + for periodic measurement. If the interval is not supported + by the sensor, the next faster interval is chosen diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index ff94007..e0be99a 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1265,6 +1265,17 @@ config SENSORS_SHT21 This driver can also be built as a module. If so, the module will be called sht21. +config SENSORS_SHT3x + tristate "Sensiron humidity and temperature sensors. SHT3x and compat." + depends on I2C + select CRC8 + help + If you say yes here you get support for the Sensiron SHT30 and SHT31 + humidity and temperature sensors. + + This driver can also be built as a module. If so, the module + will be called sht3x. + config SENSORS_SHTC1 tristate "Sensiron humidity and temperature sensors. SHTC1 and compat." depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 2ef5b7c..406b18b 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -138,6 +138,7 @@ obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o obj-$(CONFIG_SENSORS_SHT15) += sht15.o obj-$(CONFIG_SENSORS_SHT21) += sht21.o +obj-$(CONFIG_SENSORS_SHT3x) += sht3x.o obj-$(CONFIG_SENSORS_SHTC1) += shtc1.o obj-$(CONFIG_SENSORS_SIS5595) += sis5595.o obj-$(CONFIG_SENSORS_SMM665) += smm665.o diff --git a/drivers/hwmon/sht3x.c b/drivers/hwmon/sht3x.c new file mode 100644 index 0000000..707a3f8 --- /dev/null +++ b/drivers/hwmon/sht3x.c @@ -0,0 +1,725 @@ +/* Sensirion SHT3x-DIS humidity and temperature sensor driver. + * The SHT3x comes in many different versions, this driver is for the + * I2C version only. + * + * Copyright (C) 2016 Sensirion AG, Switzerland + * Author: David Frey <david.frey@sensirion.com> + * Author: Pascal Sachs <pascal.sachs@sensirion.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <asm/page.h> +#include <linux/crc8.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/platform_data/sht3x.h> + +/* commands (high precision mode) */ +static const unsigned char sht3x_cmd_measure_blocking_hpm[] = { 0x2c, 0x06 }; +static const unsigned char sht3x_cmd_measure_nonblocking_hpm[] = { 0x24, 0x00 }; + +/* commands (low power mode) */ +static const unsigned char sht3x_cmd_measure_blocking_lpm[] = { 0x2c, 0x10 }; +static const unsigned char sht3x_cmd_measure_nonblocking_lpm[] = { 0x24, 0x16 }; + +/* commands for periodic mode */ +static const unsigned char sht3x_cmd_measure_periodic_mode[] = { 0xe0, 0x00 }; +static const unsigned char sht3x_cmd_break[] = { 0x30, 0x93 }; + +/* other commands */ +static const unsigned char sht3x_cmd_read_status_reg[] = { 0xf3, 0x2d }; +static const unsigned char sht3x_cmd_clear_status_reg[] = { 0x30, 0x41 }; + +/* delays for non-blocking i2c commands, both in us */ +#define SHT3X_NONBLOCKING_WAIT_TIME_HPM 15000 +#define SHT3X_NONBLOCKING_WAIT_TIME_LPM 4000 + +#define SHT3X_WORD_LEN 2 +#define SHT3X_CMD_LENGTH 2 +#define SHT3X_CRC8_LEN 1 +#define SHT3X_RESPONSE_LENGTH 6 +#define SHT3X_CRC8_POLYNOMIAL 0x31 +#define SHT3X_CRC8_INIT 0xFF +#define SHT3X_MIN_TEMPERATURE -45000 +#define SHT3X_MAX_TEMPERATURE 130000 +#define SHT3X_MIN_HUMIDITY 0 +#define SHT3X_MAX_HUMIDITY 100000 + +enum sht3x_chips { + sht3x, + sts3x, +}; + +enum sht3x_limits { + limit_max = 0, + limit_max_hyst, + limit_min, + limit_min_hyst, +}; + +DECLARE_CRC8_TABLE(sht3x_crc8_table); + +/* periodic measure commands (high precision mode) */ +static const char periodic_measure_commands_hpm[][SHT3X_CMD_LENGTH] = { + /* 0.5 measurements per second */ + {0x20, 0x32}, + /* 1 measurements per second */ + {0x21, 0x30}, + /* 2 measurements per second */ + {0x22, 0x36}, + /* 4 measurements per second */ + {0x23, 0x34}, + /* 10 measurements per second */ + {0x27, 0x37}, +}; + +/* periodic measure commands (low power mode) */ +static const char periodic_measure_commands_lpm[][SHT3X_CMD_LENGTH] = { + /* 0.5 measurements per second */ + {0x20, 0x2f}, + /* 1 measurements per second */ + {0x21, 0x2d}, + /* 2 measurements per second */ + {0x22, 0x2b}, + /* 4 measurements per second */ + {0x23, 0x29}, + /* 10 measurements per second */ + {0x27, 0x2a}, +}; + +struct sht3x_limit_commands { + const char read_command[SHT3X_CMD_LENGTH]; + const char write_command[SHT3X_CMD_LENGTH]; +}; + +static const struct sht3x_limit_commands limit_commands[] = { + /* temp1_max, humidity1_max */ + [limit_max] = { {0xe1, 0x1f}, {0x61, 0x1d} }, + /* temp_1_max_hyst, humidity1_max_hyst */ + [limit_max_hyst] = { {0xe1, 0x14}, {0x61, 0x16} }, + /* temp1_min, humidity1_min */ + [limit_min] = { {0xe1, 0x02}, {0x61, 0x00} }, + /* temp_1_min_hyst, humidity1_min_hyst */ + [limit_min_hyst] = { {0xe1, 0x09}, {0x61, 0x0B} }, +}; + +#define SHT3X_NUM_LIMIT_CMD ARRAY_SIZE(limit_commands) + +static const u16 mode_to_update_interval[] = { + 0, + 2000, + 1000, + 500, + 250, + 100, +}; + +struct sht3x_data { + struct i2c_client *client; + struct mutex i2c_lock; /* lock for sending i2c commands */ + struct mutex data_lock; /* lock for updating driver data */ + + u8 mode; + const unsigned char *command; + u32 wait_time; /* in us*/ + unsigned long last_update; /* last update in periodic mode*/ + + struct sht3x_platform_data setup; + + /* + * cached values for temperature and humidity and limits + * the limits arrays have the following order: + * max, max_hyst, min, min_hyst + */ + int temperature; + int temperature_limits[SHT3X_NUM_LIMIT_CMD]; + u32 humidity; + u32 humidity_limits[SHT3X_NUM_LIMIT_CMD]; +}; + +static u8 get_mode_from_update_interval(u16 value) +{ + size_t index; + u8 number_of_modes = ARRAY_SIZE(mode_to_update_interval); + + if (value == 0) + return 0; + + /* find next faster update interval */ + for (index = 1; index < number_of_modes; index++) { + if (mode_to_update_interval[index] <= value) + return index; + } + + return number_of_modes - 1; +} + +static int sht3x_read_from_command(struct i2c_client *client, + struct sht3x_data *data, + const char *command, + char *buf, int length, u32 wait_time) +{ + int ret; + + mutex_lock(&data->i2c_lock); + ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH); + + if (ret != SHT3X_CMD_LENGTH) { + ret = ret < 0 ? ret : -EIO; + goto out; + } + + if (wait_time) + usleep_range(wait_time, wait_time + 1000); + + ret = i2c_master_recv(client, buf, length); + if (ret != length) { + ret = ret < 0 ? ret : -EIO; + goto out; + } + + ret = 0; +out: + mutex_unlock(&data->i2c_lock); + return ret; +} + +static int sht3x_extract_temperature(u16 raw) +{ + /* + * From datasheet: + * T = -45 + 175 * ST / 2^16 + * Adapted for integer fixed point (3 digit) arithmetic. + */ + return ((21875 * (int)raw) >> 13) - 45000; +} + +static u32 sht3x_extract_humidity(u16 raw) +{ + /* + * From datasheet: + * RH = 100 * SRH / 2^16 + * Adapted for integer fixed point (3 digit) arithmetic. + */ + return (12500 * (u32)raw) >> 13; +} + +static struct sht3x_data *sht3x_update_client(struct device *dev) +{ + struct sht3x_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + u16 interval_ms = mode_to_update_interval[data->mode]; + unsigned long interval_jiffies = msecs_to_jiffies(interval_ms); + unsigned char buf[SHT3X_RESPONSE_LENGTH]; + u16 val; + int ret = 0; + + mutex_lock(&data->data_lock); + /* + * Only update cached readings once per update interval in periodic + * mode. In single shot mode the sensor measures values on demand, so + * every time the sysfs interface is called, a measurement is triggered. + * In periodic mode however, the measurement process is handled + * internally by the sensor and reading out sensor values only makes + * sense if a new reading is available. + */ + if (time_after(jiffies, data->last_update + interval_jiffies)) { + ret = sht3x_read_from_command(client, data, data->command, buf, + sizeof(buf), data->wait_time); + if (ret) + goto out; + + val = be16_to_cpup((__be16 *)buf); + data->temperature = sht3x_extract_temperature(val); + val = be16_to_cpup((__be16 *)(buf + 3)); + data->humidity = sht3x_extract_humidity(val); + data->last_update = jiffies; + } + +out: + mutex_unlock(&data->data_lock); + if (ret) + return ERR_PTR(ret); + + return data; +} + +/* sysfs attributes */ +static ssize_t temp1_input_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct sht3x_data *data = sht3x_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", data->temperature); +} + +static ssize_t humidity1_input_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct sht3x_data *data = sht3x_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%u\n", data->humidity); +} + +/* + * limits_update must only be called from probe or with data_lock held + */ +static int limits_update(struct sht3x_data *data) +{ + int ret; + u8 index; + int temperature; + u32 humidity; + u16 raw; + char buffer[SHT3X_RESPONSE_LENGTH]; + const struct sht3x_limit_commands *commands; + struct i2c_client *client = data->client; + + for (index = 0; index < SHT3X_NUM_LIMIT_CMD; index++) { + commands = &limit_commands[index]; + ret = sht3x_read_from_command(client, data, + commands->read_command, buffer, + SHT3X_RESPONSE_LENGTH, 0); + + if (ret) + return ret; + + raw = be16_to_cpup((__be16 *)buffer); + temperature = sht3x_extract_temperature((raw & 0x01ff) << 7); + humidity = sht3x_extract_humidity(raw & 0xfe00); + data->temperature_limits[index] = temperature; + data->humidity_limits[index] = humidity; + } + + return ret; +} + +static ssize_t temp1_limit_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct sht3x_data *data = dev_get_drvdata(dev); + u8 index = to_sensor_dev_attr(attr)->index; + int temperature_limit = data->temperature_limits[index]; + + return scnprintf(buf, PAGE_SIZE, "%d\n", temperature_limit); +} + +static ssize_t humidity1_limit_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct sht3x_data *data = dev_get_drvdata(dev); + u8 index = to_sensor_dev_attr(attr)->index; + u32 humidity_limit = data->humidity_limits[index]; + + return scnprintf(buf, PAGE_SIZE, "%u\n", humidity_limit); +} + +/* + * limit_store must only be called with data_lock held + */ +static size_t limit_store(struct device *dev, + size_t count, + u8 index, + int temperature, + u32 humidity) +{ + char buffer[SHT3X_CMD_LENGTH + SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; + char *position = buffer; + int ret; + u16 raw; + struct sht3x_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + const struct sht3x_limit_commands *commands; + + commands = &limit_commands[index]; + + memcpy(position, commands->write_command, SHT3X_CMD_LENGTH); + position += SHT3X_CMD_LENGTH; + /* + * ST = (T + 45) / 175 * 2^16 + * SRH = RH / 100 * 2^16 + * adapted for fixed point arithmetic and packed the same as + * in limit_show() + */ + raw = ((u32)(temperature + 45000) * 24543) >> (16 + 7); + raw |= ((humidity * 42950) >> 16) & 0xfe00; + + *((__be16 *)position) = cpu_to_be16(raw); + position += SHT3X_WORD_LEN; + *position = crc8(sht3x_crc8_table, + position - SHT3X_WORD_LEN, + SHT3X_WORD_LEN, + SHT3X_CRC8_INIT); + + mutex_lock(&data->i2c_lock); + ret = i2c_master_send(client, buffer, sizeof(buffer)); + mutex_unlock(&data->i2c_lock); + + if (ret != sizeof(buffer)) + return ret < 0 ? ret : -EIO; + + data->temperature_limits[index] = temperature; + data->humidity_limits[index] = humidity; + return count; +} + +static ssize_t temp1_limit_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + int temperature; + int ret; + struct sht3x_data *data = dev_get_drvdata(dev); + u8 index = to_sensor_dev_attr(attr)->index; + + ret = kstrtoint(buf, 0, &temperature); + if (ret) + return ret; + + temperature = clamp_val(temperature, SHT3X_MIN_TEMPERATURE, + SHT3X_MAX_TEMPERATURE); + mutex_lock(&data->data_lock); + ret = limit_store(dev, count, index, temperature, + data->humidity_limits[index]); + mutex_unlock(&data->data_lock); + + return ret; +} + +static ssize_t humidity1_limit_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + u32 humidity; + int ret; + struct sht3x_data *data = dev_get_drvdata(dev); + u8 index = to_sensor_dev_attr(attr)->index; + + ret = kstrtou32(buf, 0, &humidity); + if (ret) + return ret; + + humidity = clamp_val(humidity, SHT3X_MIN_HUMIDITY, SHT3X_MAX_HUMIDITY); + mutex_lock(&data->data_lock); + ret = limit_store(dev, count, index, data->temperature_limits[index], + humidity); + mutex_unlock(&data->data_lock); + + return ret; +} + +static void sht3x_select_command(struct sht3x_data *data) +{ + /* + * In blocking mode (clock stretching mode) the I2C bus + * is blocked for other traffic, thus the call to i2c_master_recv() + * will wait until the data is ready. For non blocking mode, we + * have to wait ourselves. + */ + if (data->mode > 0) { + data->command = sht3x_cmd_measure_periodic_mode; + data->wait_time = 0; + } else if (data->setup.blocking_io) { + data->command = data->setup.high_precision ? + sht3x_cmd_measure_blocking_hpm : + sht3x_cmd_measure_blocking_lpm; + data->wait_time = 0; + } else { + if (data->setup.high_precision) { + data->command = sht3x_cmd_measure_nonblocking_hpm; + data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_HPM; + } else { + data->command = sht3x_cmd_measure_nonblocking_lpm; + data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_LPM; + } + } +} + +static int status_register_read(struct device *dev, + struct device_attribute *attr, + char *buffer, int length) +{ + int ret; + struct sht3x_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + + ret = sht3x_read_from_command(client, data, sht3x_cmd_read_status_reg, + buffer, length, 0); + + return ret; +} + +static ssize_t temp1_alarm_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; + int ret; + + ret = status_register_read(dev, attr, buffer, + SHT3X_WORD_LEN + SHT3X_CRC8_LEN); + if (ret) + return ret; + + return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x04)); +} + +static ssize_t humidity1_alarm_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; + int ret; + + ret = status_register_read(dev, attr, buffer, + SHT3X_WORD_LEN + SHT3X_CRC8_LEN); + if (ret) + return ret; + + return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x08)); +} + +static ssize_t update_interval_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct sht3x_data *data = dev_get_drvdata(dev); + + return scnprintf(buf, PAGE_SIZE, "%u\n", + mode_to_update_interval[data->mode]); +} + +static ssize_t update_interval_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + u16 update_interval; + u8 mode; + int ret; + const char *command; + struct sht3x_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + + ret = kstrtou16(buf, 0, &update_interval); + if (ret) + return ret; + + mode = get_mode_from_update_interval(update_interval); + + mutex_lock(&data->data_lock); + /* mode did not change */ + if (mode == data->mode) { + mutex_unlock(&data->data_lock); + return count; + } + + mutex_lock(&data->i2c_lock); + /* + * Abort periodic measure mode. + * To do any changes to the configuration while in periodic mode, we + * have to send a break command to the sensor, which then falls back + * to single shot (mode = 0). + */ + if (data->mode > 0) { + ret = i2c_master_send(client, sht3x_cmd_break, + SHT3X_CMD_LENGTH); + if (ret != SHT3X_CMD_LENGTH) + goto out; + data->mode = 0; + } + + if (mode > 0) { + if (data->setup.high_precision) + command = periodic_measure_commands_hpm[mode - 1]; + else + command = periodic_measure_commands_lpm[mode - 1]; + + /* select mode */ + ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH); + if (ret != SHT3X_CMD_LENGTH) + goto out; + } + + /* select mode and command */ + data->mode = mode; + sht3x_select_command(data); + +out: + mutex_unlock(&data->i2c_lock); + mutex_unlock(&data->data_lock); + if (ret != SHT3X_CMD_LENGTH) + return ret < 0 ? ret : -EIO; + + return count; +} + +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, temp1_input_show, NULL, 0); +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, humidity1_input_show, + NULL, 0); +static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, + temp1_limit_show, temp1_limit_store, + limit_max); +static SENSOR_DEVICE_ATTR(humidity1_max, S_IRUGO | S_IWUSR, + humidity1_limit_show, humidity1_limit_store, + limit_max); +static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR, + temp1_limit_show, temp1_limit_store, + limit_max_hyst); +static SENSOR_DEVICE_ATTR(humidity1_max_hyst, S_IRUGO | S_IWUSR, + humidity1_limit_show, humidity1_limit_store, + limit_max_hyst); +static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, + temp1_limit_show, temp1_limit_store, + limit_min); +static SENSOR_DEVICE_ATTR(humidity1_min, S_IRUGO | S_IWUSR, + humidity1_limit_show, humidity1_limit_store, + limit_min); +static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO | S_IWUSR, + temp1_limit_show, temp1_limit_store, + limit_min_hyst); +static SENSOR_DEVICE_ATTR(humidity1_min_hyst, S_IRUGO | S_IWUSR, + humidity1_limit_show, humidity1_limit_store, + limit_min_hyst); +static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, temp1_alarm_show, NULL, 0); +static SENSOR_DEVICE_ATTR(humidity1_alarm, S_IRUGO, humidity1_alarm_show, + NULL, 0); +static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR, + update_interval_show, update_interval_store, 0); + +static struct attribute *sht3x_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_humidity1_input.dev_attr.attr, + &sensor_dev_attr_temp1_max.dev_attr.attr, + &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, + &sensor_dev_attr_humidity1_max.dev_attr.attr, + &sensor_dev_attr_humidity1_max_hyst.dev_attr.attr, + &sensor_dev_attr_temp1_min.dev_attr.attr, + &sensor_dev_attr_temp1_min_hyst.dev_attr.attr, + &sensor_dev_attr_humidity1_min.dev_attr.attr, + &sensor_dev_attr_humidity1_min_hyst.dev_attr.attr, + &sensor_dev_attr_temp1_alarm.dev_attr.attr, + &sensor_dev_attr_humidity1_alarm.dev_attr.attr, + &sensor_dev_attr_update_interval.dev_attr.attr, + NULL +}; + +static struct attribute *sts3x_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + NULL +}; + +ATTRIBUTE_GROUPS(sht3x); +ATTRIBUTE_GROUPS(sts3x); + +static int sht3x_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct sht3x_data *data; + struct device *hwmon_dev; + struct i2c_adapter *adap = client->adapter; + struct device *dev = &client->dev; + const struct attribute_group **attribute_groups; + + /* + * we require full i2c support since the sht3x uses multi-byte read and + * writes as well as multi-byte commands which are not supported by + * the smbus protocol + */ + if (!i2c_check_functionality(adap, I2C_FUNC_I2C)) + return -ENODEV; + + ret = i2c_master_send(client, sht3x_cmd_clear_status_reg, + SHT3X_CMD_LENGTH); + if (ret != SHT3X_CMD_LENGTH) + return ret < 0 ? ret : -ENODEV; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->setup.blocking_io = false; + data->setup.high_precision = true; + data->mode = 0; + data->last_update = 0; + data->client = client; + crc8_populate_msb(sht3x_crc8_table, SHT3X_CRC8_POLYNOMIAL); + + if (client->dev.platform_data) + data->setup = *(struct sht3x_platform_data *)dev->platform_data; + + sht3x_select_command(data); + + mutex_init(&data->i2c_lock); + mutex_init(&data->data_lock); + + ret = limits_update(data); + if (ret) + return ret; + + if (id->driver_data == sts3x) + attribute_groups = sts3x_groups; + else + attribute_groups = sht3x_groups; + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, + client->name, + data, + attribute_groups); + + if (IS_ERR(hwmon_dev)) + dev_dbg(dev, "unable to register hwmon device\n"); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +/* device ID table */ +static const struct i2c_device_id sht3x_ids[] = { + {"sht3x", sht3x}, + {"sts3x", sts3x}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, sht3x_ids); + +static struct i2c_driver sht3x_i2c_driver = { + .driver.name = "sht3x", + .probe = sht3x_probe, + .id_table = sht3x_ids, +}; + +module_i2c_driver(sht3x_i2c_driver); + +MODULE_AUTHOR("David Frey <david.frey@sensirion.com>"); +MODULE_AUTHOR("Pascal Sachs <pascal.sachs@sensirion.com>"); +MODULE_DESCRIPTION("Sensirion SHT3x humidity and temperature sensor driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/platform_data/sht3x.h b/include/linux/platform_data/sht3x.h new file mode 100644 index 0000000..2e5eea3 --- /dev/null +++ b/include/linux/platform_data/sht3x.h @@ -0,0 +1,25 @@ +/* + * Copyright (C) 2016 Sensirion AG, Switzerland + * Author: David Frey <david.frey@sensirion.com> + * Author: Pascal Sachs <pascal.sachs@sensirion.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#ifndef __SHT3X_H_ +#define __SHT3X_H_ + +struct sht3x_platform_data { + bool blocking_io; + bool high_precision; +}; +#endif /* __SHT3X_H_ */ |
