Documentation/firmware-guide/acpi/chromeos-acpi-device.rst

Source file repositories/reference/linux-study-clean/Documentation/firmware-guide/acpi/chromeos-acpi-device.rst

File Facts

System: Linux kernel
Corpus path: Documentation/firmware-guide/acpi/chromeos-acpi-device.rst
Extension: .rst
Size: 8877 bytes
Lines: 363
Domain: Support Tooling And Documentation
Bucket: Documentation
Inferred role: Support Tooling And Documentation: documentation
Status: atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.. SPDX-License-Identifier: GPL-2.0

=====================
Chrome OS ACPI Device
=====================

Hardware functionality specific to Chrome OS is exposed through a Chrome OS ACPI device.
The plug and play ID of a Chrome OS ACPI device is GGL0001 and the hardware ID is
GOOG0016.  The following ACPI objects are supported:

.. flat-table:: Supported ACPI Objects
   :widths: 1 2
   :header-rows: 1

   * - Object
     - Description

   * - CHSW
     - Chrome OS switch positions

   * - HWID
     - Chrome OS hardware ID

   * - FWID
     - Chrome OS firmware version

   * - FRID
     - Chrome OS read-only firmware version

   * - BINF
     - Chrome OS boot information

   * - GPIO
     - Chrome OS GPIO assignments

   * - VBNV
     - Chrome OS NVRAM locations

   * - VDTA
     - Chrome OS verified boot data

   * - FMAP
     - Chrome OS flashmap base address

   * - MLST
     - Chrome OS method list

CHSW (Chrome OS switch positions)
=================================
This control method returns the switch positions for Chrome OS specific hardware switches.

Arguments:
----------
None

Result code:
------------
An integer containing the switch positions as bitfields:

.. flat-table::
   :widths: 1 2

   * - 0x00000002
     - Recovery button was pressed when x86 firmware booted.

   * - 0x00000004
     - Recovery button was pressed when EC firmware booted. (required if EC EEPROM is
       rewritable; otherwise optional)

   * - 0x00000020

Annotation

Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.