| .. 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 |
| =============================== ======= ======================================== |
