Documentation/ABI/testing/sysfs-devices-power_state
Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-devices-power_state
File Facts
- System
- Linux kernel
- Corpus path
Documentation/ABI/testing/sysfs-devices-power_state- Extension
[no extension]- Size
- 877 bytes
- Lines
- 21
- 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
What: /sys/devices/.../power_state
Date: January 2013
Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Description:
The /sys/devices/.../power_state attribute is only present for
device objects representing ACPI device nodes that provide power
management methods.
If present, it contains a string representing the current ACPI
power state of the given device node. Its possible values,
"D0", "D1", "D2", "D3hot", and "D3cold", reflect the power state
names defined by the ACPI specification (ACPI 4 and above).
If the device node uses shared ACPI power resources, this state
determines a list of power resources required not to be turned
off. However, some power resources needed by the device node in
higher-power (lower-number) states may also be ON because of
some other devices using them at the moment.
This attribute is read-only.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.