/usr/bin/acpihelp

Illegal option: --

Intel ACPI Component Architecture
ACPI Help Utility version 20260930
Copyright (c) 2000 - 2026 Intel Corporation

Usage: acpihelp <options> [Name/Prefix | HexValue]
Options:
  -h                      Display help
  -v                      Display version information
  -vd                     Display build date and time

AML Names and Encodings (ACPI Machine Language):
  -a [Name/Prefix | *]    Display both ASL operator and AML opcode name(s)
  -g [Name/Prefix | *]    Display AML grammar elements(s)
  -m [Name/Prefix | *]    Display AML opcode name(s)

ACPI Values:
  -e [HexValue]           Decode ACPICA exception code
  -o [HexValue]           Decode hex AML opcode
  -x [HexValue]           Decode iASL exception code

ASL Names and Symbols (ACPI Source Language):
  -k [Name/Prefix | *]    Display ASL non-operator keyword(s)
  -p [Name/Prefix | *]    Display ASL predefined method name(s)
  -s [Name/Prefix | *]    Display ASL operator name(s)

Other miscellaneous ACPI Names:
  -i [Name/Prefix | *]    Display ACPI/PNP Hardware ID(s)
  -d                      Display iASL Preprocessor directives
  -t                      Display supported ACPI tables
  -u                      Display ACPI-related UUIDs

Name/Prefix or HexValue not specified means "Display All"

Default search with valid Name/Prefix and no options:
    Find ASL/AML operator names - if NamePrefix does not start with underscore
    Find ASL predefined method names - if NamePrefix starts with underscore