| .. SPDX-License-Identifier: GPL-2.0 |
| |
| Kernel driver sht4x |
| =================== |
| |
| Supported Chips: |
| |
| * Sensirion SHT4X |
| |
| Prefix: 'sht4x' |
| |
| Addresses scanned: None |
| |
| Datasheet: |
| |
| English: https://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/2_Humidity_Sensors/Datasheets/Sensirion_Humidity_Sensors_SHT4x_Datasheet.pdf |
| |
| Author: Navin Sankar Velliangiri <navin@linumiz.com> |
| |
| |
| Description |
| ----------- |
| |
| This driver implements support for the Sensirion SHT4x chip, a humidity |
| and temperature sensor. Temperature is measured in degree celsius, relative |
| humidity is expressed as a percentage. In sysfs interface, all values are |
| scaled by 1000, i.e. the value for 31.5 degrees celsius is 31500. |
| |
| Usage Notes |
| ----------- |
| |
| The device communicates with the I2C protocol. Sensors can have the I2C |
| address 0x44. See Documentation/i2c/instantiating-devices.rst for methods |
| to instantiate the device. |
| |
| Sysfs entries |
| ------------- |
| |
| =============== ============================================ |
| temp1_input Measured temperature in millidegrees Celsius |
| humidity1_input Measured humidity in %H |
| update_interval The minimum interval for polling the sensor, |
| in milliseconds. Writable. Must be at least |
| 2000. |
| heater_power The requested heater power, in milliwatts. |
| Available values: 20, 110, 200 (default: 200). |
| heater_time The requested operating time of the heater, |
| in milliseconds. |
| Available values: 100, 1000 (default 1000). |
| heater_enable Enable the heater with the selected power |
| and for the selected time in order to remove |
| condensed water from the sensor surface. The |
| heater cannot be manually turned off once |
| enabled (it will automatically turn off |
| after completing its operation). |
| |
| - 0: turned off (read-only value) |
| - 1: turn on |
| =============== ============================================ |