| .. SPDX-License-Identifier: GPL-2.0-or-later | |
| Kernel driver ChipCap2 | |
| ====================== | |
| Supported chips: | |
| * Amphenol CC2D23, CC2D23S, CC2D25, CC2D25S, CC2D33, CC2D33S, CC2D35, CC2D35S | |
| Prefix: 'chipcap2' | |
| Addresses scanned: - | |
| Datasheet: https://www.amphenol-sensors.com/en/telaire/humidity/527-humidity-sensors/3095-chipcap-2 | |
| Author: | |
| - Javier Carrasco <javier.carrasco.cruz@gmail.com> | |
| Description | |
| ----------- | |
| This driver implements support for the Amphenol ChipCap 2, a humidity and | |
| temperature chip family. Temperature is measured in milli degrees celsius, | |
| relative humidity is expressed as a per cent mille. The measurement ranges | |
| are the following: | |
| - Relative humidity: 0 to 100000 pcm (14-bit resolution) | |
| - Temperature: -40000 to +125000 m°C (14-bit resolution) | |
| The device communicates with the I2C protocol and uses the I2C address 0x28 | |
| by default. | |
| Depending on the hardware configuration, up to two humidity alarms to control | |
| minimum and maximum values are provided. Their thresholds and hystersis can be | |
| configured via sysfs. | |
| Thresholds and hysteris must be provided as a per cent mille. These values | |
| might be truncated to match the 14-bit device resolution (6.1 pcm/LSB) | |
| Known Issues | |
| ------------ | |
| The driver does not support I2C address and command window length modification. | |
| sysfs-Interface | |
| --------------- | |
| The following list includes the sysfs attributes that the driver always provides, | |
| their permissions and a short description: | |
| =============================== ======= ======================================== | |
| Name Perm Description | |
| =============================== ======= ======================================== | |
| temp1_input: RO temperature input | |
| humidity1_input: RO humidity input | |
| =============================== ======= ======================================== | |
| The following list includes the sysfs attributes that the driver may provide | |
| depending on the hardware configuration: | |
| =============================== ======= ======================================== | |
| Name Perm Description | |
| =============================== ======= ======================================== | |
| humidity1_min: RW humidity low limit. Measurements under | |
| this limit trigger a humidity low alarm | |
| humidity1_max: RW humidity high limit. Measurements above | |
| this limit trigger a humidity high alarm | |
| humidity1_min_hyst: RW humidity low hystersis | |
| humidity1_max_hyst: RW humidity high hystersis | |
| humidity1_min_alarm: RO humidity low alarm indicator | |
| humidity1_max_alarm: RO humidity high alarm indicator | |
| humidity1_label: RO descriptive name for the sensor | |
| temp1_label: RO descriptive name for the sensor | |
| =============================== ======= ======================================== |