NAME
pmu —
support for Power Management Units
found in all Apple laptops and some desktop Power Macintosh
computers
SYNOPSIS
pmu* at obio?
nadb* at pmu?
battery* at pmu?
smartbat* at pmu?
DESCRIPTION
Thepmu driver provides support for the Power Management
Unit found in Apple laptops and some desktop Power Macintosh computers.
Functions controlled by the PMU include the real time clock, ADB, power,
batteries, on some laptops like the PowerBook 3400c and similar machines it
also controls hotkeys and display brightness, on others it provides an
iic(9)
bus and on some it controls CPU speed. On many older machines it also provides
access to some non-volatile memory and thermal sensors. Not all those features
are present on all machines, for instance Power Macintosh G4 and later
machines don't have ADB, many more recent laptops have display brightness and
backlight control built into the graphics controller instead of the PMU, only
a few older PowerBooks use the PMU for CPU speed control and newer machines
use a different way to access non-volatile memory. However, all known PMUs so
far provide a real time clock and power control.
Notes by model
Real time clock and power control are present and supported on all machines that can run NetBSD/macppc, ADB is supported when present.
PowerBook 2400, 3400c, and 3500- Battery status and thermal sensors found on the mainboard and in the battery pack are supported by the battery(4) driver, values can be read via envsys(4). Hotkeys for brightness control are supported, CPU speed control and parameter RAM are present but unsupported.
Power Macintosh G4- ADB is not present, iic(9) is present but unsupported.
SEE ALSO
BUGS
Some features are currently unsupported, like the iic(9) bus, access to parameter RAM and CPU speed control.