Documentation/ABI/testing/sysfs-class-led-trigger-pattern

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-class-led-trigger-pattern

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-class-led-trigger-pattern
Extension
[no extension]
Size
1790 bytes
Lines
51
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.

Dependency Surface

Detected Declarations

Annotated Snippet

What:		/sys/class/leds/<led>/pattern
Date:		September 2018
KernelVersion:	4.20
Description:
		Specify a software pattern for the LED, that supports altering
		the brightness for the specified duration with one software
		timer. It can do gradual dimming and step change of brightness.

		The pattern is given by a series of tuples, of brightness and
		duration (ms).

		The exact format is described in:
		Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt

What:		/sys/class/leds/<led>/hr_pattern
Date:		April 2024
Description:
		Specify a software pattern for the LED, that supports altering
		the brightness for the specified duration with one software
		timer. It can do gradual dimming and step change of brightness.

		Unlike the /sys/class/leds/<led>/pattern, this attribute runs
		a pattern on high-resolution timer (hrtimer).

What:		/sys/class/leds/<led>/hw_pattern
Date:		September 2018
KernelVersion:	4.20
Description:
		Specify a hardware pattern for the LED, for LED hardware that
		supports autonomously controlling brightness over time, according
		to some preprogrammed hardware patterns. It deactivates any active
		software pattern.

		Since different LED hardware can have different semantics of
		hardware patterns, each driver is expected to provide its own
		description for the hardware patterns in their documentation
		file at Documentation/leds/.

What:		/sys/class/leds/<led>/repeat
Date:		September 2018
KernelVersion:	4.20
Description:
		Specify a pattern repeat number. -1 means repeat indefinitely,
		other negative numbers and number 0 are invalid.

		This file will always return the originally written repeat
		number.

		It should be noticed that some leds, like EL15203000 may
		only support indefinitely patterns, so they always store -1.

Annotation

Implementation Notes