3af350929e
The Amphenol ChipCap 2 is a capacitive polymer humidity and temperature sensor with an integrated EEPROM and minimum/maximum humidity alarms. All device variants offer an I2C interface and depending on the part number, two different output modes: - CC2D: digital output - CC2A: analog (PDM) output This driver adds support for the digital variant (CC2D part numbers), which includes the following part numbers: - non-sleep measurement mode (CC2D23, CC2D25, CC2D33, CC2D35) - sleep measurement mode (CC2D23S, CC2D25S, CC2D33S, CC2D35S) The Chipcap 2 EEPROM can be accessed to configure a series of parameters like the minimum/maximum humidity alarm threshold and hysteresis. The EEPROM is only accessible in the command window after a power-on reset. The default window lasts 10 ms if no Start_CM command is sent. After the command window is finished (either after the mentioned timeout of after a Start_NOM command is sent), the device enters the normal operation mode and makes a first measurement automatically. Unfortunately, the device does not provide any hardware or software reset and therefore the driver must trigger power cycles to enter the command mode. A dedicated, external regulator is required for that. This driver keeps the device off until a measurement or access to the EEPROM is required, making use of the first automatic measurement to avoid different code paths for sleep and non-sleep devices. The minimum and maximum humidity alarms are configured with two registers per alarm: one stores the alarm threshold and the other one keeps the value that turns off the alarm. The alarm signals are only updated when a measurement is carried out. Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com> Link: https://lore.kernel.org/r/20240130-topic-chipcap2-v6-5-260bea05cf9b@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net> |
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.