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ASMC(4)		       FreeBSD Kernel Interfaces Manual		       ASMC(4)

NAME
     asmc -- device driver for the Apple System	Management Console (SMC)

SYNOPSIS
     To	compile	this driver into the kernel, place the following line in your
     kernel configuration file:

	   device asmc

     Alternatively, to load the	driver as a module at boot time, place the
     following line in loader.conf(5):

	   asmc_load="YES"

DESCRIPTION
     The asmc driver controls the Apple	System Management Console (SMC for
     short) found on Intel Apple systems.

     The SMC is	known to be found on the following systems:

	   +o   MacBook
	   +o   MacBook Pro
	   +o   Intel MacMini
	   +o   Mac Pro
	   +o   MacBook Air
	   +o   Intel iMac

     With this driver, you can configure your keyboard backlight brightness,
     check temperatures	of several sensors, check the speed of the internal
     fans and check the	status of the Sudden Motion Sensor.

     Variables related to the SMC control and inspection are exported via
     sysctl(3) under the device	tree dev.asmc.

KEYBOARD BACKLIGHT
     On	MacBook	Pro systems, you can control the keyboard brightness by	writ-
     ing a value to the	dev.asmc.%d.light.control sysctl MIB.

     The following sysctl MIBs contains	the raw	value returned by the left and
     right light sensors: dev.asmc.%d.light.left or dev.asmc.%d.light.right.

TEMPERATURES
     The number	of temperature sensors and their description varies among sys-
     tems.  You	can inspect the	temperature sensors on your system by travers-
     ing the dev.asmc.temp sysctl MIB.

     All values	are in degrees celsius.

SYSTEM FANS
     The dev.asmc.fan.%d sysctl	tree contains the leaf nodes speed, safespeed,
     minspeed, maxspeed	and targetspeed.  Each of these	leaf nodes represent
     the current fan speed, the	safest minimum fan speed, the minimum speed
     and the maximum speed respectively.

     All values	are in RPM.

SUDDEN MOTION SENSOR
     The Sudden	Motion Sensor (SMS for short) is a device that detects laptop
     movement and notifies the operating system	via an interrupt.  The sysctl
     MIBs present under	dev.asmc.sms all relate	to the SMS.

     The most interesting usage	of this	device is to park the disk heads when
     the laptop	is moved harshly.  First, you need to install ataidle(8)
     (ports/sysutils/ataidle) and then configure devd(8) the following way:

	   notify 0 {
		   match "system"	   "ACPI";
		   match "subsystem"	   "asmc";
		   action		   "/usr/local/sbin/ataidle -s X Y";
	   };

     Do	not forget to change the X and Y values	in the command above.

     Also, please note that parking the	disk heads too many times can dramati-
     cally reduce your hard drive's life span.	Do not rely solely on the SMS
     to	protect	your hard drive: good care and common sense can	increase your
     hard drive's life.

SEE ALSO
     ataidle(8)	(ports/sysutils/ataidle), devd(8), sysctl(8)

HISTORY
     The asmc driver first appeared in FreeBSD 8.0.

AUTHORS
     Rui Paulo <rpaulo@FreeBSD.org> (Google Summer of Code project)

BUGS
     Support for the latest models was never tested and	is most	likely not
     fully working.

FreeBSD	11.1			 July 27, 2009			  FreeBSD 11.1
NAME | SYNOPSIS | DESCRIPTION | KEYBOARD BACKLIGHT | TEMPERATURES | SYSTEM FANS | SUDDEN MOTION SENSOR | SEE ALSO | HISTORY | AUTHORS | BUGS

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