What:		/sys/devices/platform/samsung/performance_level
Date:		January 1, 2010
KernelVersion:	2.6.33
Contact:	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Description:	Some Samsung laptops have different "performance levels"
		that are can be modified by a function key, and by this
		sysfs file.  These values don't always make a whole lot
		of sense, but some users like to modify them to keep
		their fans quiet at all costs.  Reading from this file
		will show the current performance level.  Writing to the
		file can change this value.
			Valid options:
				"silent"
				"normal"
				"overclock"
		Note that not all laptops support all of these options.
		Specifically, not all support the "overclock" option,
		and it's still unknown if this value even changes
		anything, other than making the user feel a bit better.

What:		/sys/devices/platform/samsung/battery_life_extender
Date:		December 1, 2011
KernelVersion:	3.3
Contact:	Corentin Chary <corentin.chary@gmail.com>
Description:	Max battery charge level can be modified, battery cycle
		life can be extended by reducing the max battery charge
		level.
		0 means normal battery mode (100% charge)
		1 means battery life extender mode (80% charge)

What:		/sys/devices/platform/samsung/usb_charge
Date:		December 1, 2011
KernelVersion:	3.3
Contact:	Corentin Chary <corentin.chary@gmail.com>
Description:	Use your USB ports to charge devices, even
		when your laptop is powered off.
		1 means enabled, 0 means disabled.