64 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			64 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| What:		/sys/class/leds/<led>/brightness
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| Date:		March 2006
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| KernelVersion:	2.6.17
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| Contact:	Richard Purdie <rpurdie@rpsys.net>
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| Description:
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| 		Set the brightness of the LED. Most LEDs don't
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| 		have hardware brightness support, so will just be turned on for
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| 		non-zero brightness settings. The value is between 0 and
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| 		/sys/class/leds/<led>/max_brightness.
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| 
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| 		Writing 0 to this file clears active trigger.
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| 
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| 		Writing non-zero to this file while trigger is active changes the
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| 		top brightness trigger is going to use.
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| 
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| What:		/sys/class/leds/<led>/max_brightness
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| Date:		March 2006
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| KernelVersion:	2.6.17
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| Contact:	Richard Purdie <rpurdie@rpsys.net>
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| Description:
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| 		Maximum brightness level for this LED, default is 255 (LED_FULL).
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| 
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| 		If the LED does not support different brightness levels, this
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| 		should be 1.
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| 
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| What:		/sys/class/leds/<led>/brightness_hw_changed
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| Date:		January 2017
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| KernelVersion:	4.11
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| Description:
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| 		Last hardware set brightness level for this LED. Some LEDs
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| 		may be changed autonomously by hardware/firmware. Only LEDs
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| 		where this happens and the driver can detect this, will have
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| 		this file.
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| 
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| 		This file supports poll() to detect when the hardware changes
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| 		the brightness.
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| 
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| 		Reading this file will return the last brightness level set
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| 		by the hardware, this may be different from the current
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| 		brightness. Reading this file when no hw brightness change
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| 		event has happened will return an ENODATA error.
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| 
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| What:		/sys/class/leds/<led>/trigger
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| Date:		March 2006
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| KernelVersion:	2.6.17
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| Contact:	Richard Purdie <rpurdie@rpsys.net>
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| Description:
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| 		Set the trigger for this LED. A trigger is a kernel based source
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| 		of LED events.
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| 		You can change triggers in a similar manner to the way an IO
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| 		scheduler is chosen. Trigger specific parameters can appear in
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| 		/sys/class/leds/<led> once a given trigger is selected. For
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| 		their documentation see sysfs-class-led-trigger-*.
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| 
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| What:		/sys/class/leds/<led>/inverted
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| Date:		January 2011
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| KernelVersion:	2.6.38
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| Contact:	Richard Purdie <rpurdie@rpsys.net>
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| Description:
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| 		Invert the LED on/off state. This parameter is specific to
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| 		gpio and backlight triggers. In case of the backlight trigger,
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| 		it is useful when driving a LED which is intended to indicate
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| 		a device in a standby like state.
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