5f9952548d
This patch introduces a driver for the ChromeOS human presence sensor (aka. HPS). The driver supports a sensor connected to the I2C bus and identified as "GOOG0020" in the ACPI tables. When loaded, the driver exports the sensor to userspace through a character device. This device only supports power management, i.e., communication with the sensor must be done through regular I2C transmissions from userspace. Power management is implemented by enabling the respective power GPIO while at least one userspace process holds an open fd on the character device. By default, the device is powered down if there are no active clients. Note that the driver makes no effort to preserve the state of the sensor between power down and power up events. Userspace is responsible for reinitializing any needed state once power has been restored. The device firmware, I2C protocol and other documentation is available at https://chromium.googlesource.com/chromiumos/platform/hps-firmware. Co-developed-by: Sami Kyöstilä <skyostil@chromium.org> Signed-off-by: Sami Kyöstilä <skyostil@chromium.org> Signed-off-by: Dan Callaghan <dcallagh@chromium.org> Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org> Link: https://lore.kernel.org/r/20221018040623.2173441-1-dcallagh@chromium.org |
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| 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 | ||
| .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.