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acpi_thermal(4) [freebsd man page]

ACPI_THERMAL(4) 					   BSD Kernel Interfaces Manual 					   ACPI_THERMAL(4)

acpi_thermal -- ACPI thermal management subsystem SYNOPSIS
device acpi DESCRIPTION
The acpi_thermal driver provides the thermal management features of the ACPI module. This driver has a sysctl(8) interface and a devd(8) notification interface. The sysctls export properties of each ACPI thermal zone object. There can be multiple thermal zones in a system. For example, each CPU and the enclosure could all be separate thermal zones, each with its own setpoints and cooling devices. Thermal zones are numbered sequentially in the order they appear in the AML. The acpi_thermal driver also activates the active cooling system according to each thermal zone's setpoints. SYSCTL VARIABLES
hw.acpi.thermal.min_runtime Number of seconds to continue active cooling once started. A new active cooling level will not be selected until this interval expires. hw.acpi.thermal.polling_rate Number of seconds between polling the current temperature. hw.acpi.thermal.user_override If set to 1, allow user override of various setpoints (below). The original values for these settings are obtained from the BIOS and system overheating and possible damage could occur if changed. Default is 0 (no override). Current active cooling system state. If this is non-negative, the appropriate _AC%d object is running. Set this value to the desired active cooling level to force the corresponding fan object to the appropriate level. If set to 1, passive cooling is enabled. It does cooling without fans using cpufreq(4) as the mechanism for controlling CPU speed. Default is enabled for tz0 where it is available. Current thermal zone status. These are bit-masked values. Current temperature for this zone. Temperature to start passive cooling by throttling down CPU, etc. This value can be overridden by the user. Temperature to start critical suspend to disk (S4). This value can be overridden by the user. Temperature to start critical shutdown (S5). This value can be overridden by the user. Temperatures at which to switch to the corresponding active cooling level. The lower the _ACx value, the higher the cooling power. All temperatures are printed in Celsius. Values can be set in Celsius (by providing a trailing "C") or Kelvin (by leaving off any trailing letter). When setting a value by sysctl(8), do not specify a trailing decimal (i.e., 90C instead of 90.0C). NOTIFIES
Notifies are passed to userland via devd(8). See /etc/devd.conf and devd.conf(5) for examples. The acpi_thermal driver sends events with the following attributes: system ACPI subsystem Thermal type The fully qualified thermal zone object path as in the ASL. notify An integer designating the event: 0x80 Current temperature has changed. 0x81 One or more trip points (_ACx, _PSV) have changed. 0x82 One or more device lists (_ALx, _PSL, _TZD) have changed. 0xcc Non-standard notify that the system will shutdown if the temperature stays above _CRT or _HOT for one more poll cycle. SEE ALSO
acpi(4), cpufreq(4), acpidump(8) AUTHORS
Michael Smith This manual page was written by Takanori Watanabe. BSD
March 17, 2007 BSD

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ACPI_TOSHIBA(4) 					 BSD/i386 Kernel Interfaces Manual					   ACPI_TOSHIBA(4)

acpi_toshiba -- Toshiba HCI interface SYNOPSIS
To compile this driver into the kernel, place the following line in your kernel configuration file: device acpi_toshiba Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5): acpi_toshiba_load="YES" DESCRIPTION
HCI is Toshiba's Hardware Control Interface which is somewhat uniform across their models. The acpi_toshiba driver allows the user to manip- ulate HCI-controlled hardware using a number of sysctl(8) variables. SYSCTL VARIABLES
The following sysctls are currently implemented: Causes active cooling to be forcibly enabled ('1') or disabled ('0') regardless of the current temperature. Sets the active display to use according to a bitwise OR of the following: 0 No display 1 LCD 2 CRT 4 TV-Out Only some systems (i.e., the Libretto L5) support video switching via this hardware-specific driver. Use the acpi_video(4) driver for generic video output support. Makes the LCD backlight brighter or dimmer (higher values are brighter). Turns the LCD backlight on and off. Sets the CPU speed to the specified speed. This provides functionality similar to the hw.acpi.cpu.throttle_state variable. Higher sysctl values mean lower CPU speeds. Defaults for these variables can be set in sysctl.conf(5), which is parsed at boot-time. LOADER TUNABLES
The tunable enables or disables the function keys on the keyboard. Function keys are enabled by default. This behaviour can be changed at the loader(8) prompt or in loader.conf(5). SEE ALSO
acpi(4), acpi_video(4), loader.conf(5), sysctl.conf(5), sysctl(8) HISTORY
The acpi_toshiba driver first appeared in FreeBSD 5.1. AUTHORS
The acpi_toshiba driver was written by Hiroyuki Aizu <>. This manual page was written by Philip Paeps <>. BSD
February 19, 2004 BSD

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