path: root/Documentation/ABI/stable
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authorThomas Renninger <>2011-11-04 03:33:46 +0100
committerLen Brown <>2011-11-06 20:48:42 -0500
commit362b646062b2073bd5c38efb42171d86e4f717e6 (patch)
tree6c98cdb7aa5d9be22e2b24ca06b822455ef4b9f5 /Documentation/ABI/stable
parentc3b92c8787367a8bb53d57d9789b558f1295cc96 (diff)
ACPI: Export FADT pm_profile integer value to userspace
There are a lot userspace approaches to detect the usage of the platform (laptop, workstation, server, ...) and adjust kernel tunables accordingly (io/process scheduler, power management, ...). These approaches need constant maintaining and are ugly to implement (detect PCMCIA controller -> laptop, does not work on recent systems anymore, ...) On ACPI systems there is an easy and reliable way (if implemented in BIOS and most recent platforms have this value set). -> export it to userspace. Signed-off-by: Thomas Renninger <> Acked-by: Rafael J. Wysocki <> Signed-off-by: Len Brown <>
Diffstat (limited to 'Documentation/ABI/stable')
1 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/ABI/stable/sysfs-acpi-pmprofile b/Documentation/ABI/stable/sysfs-acpi-pmprofile
new file mode 100644
index 000000000000..964c7a8afb26
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-acpi-pmprofile
@@ -0,0 +1,22 @@
+What: /sys/firmware/acpi/pm_profile
+Date: 03-Nov-2011
+KernelVersion: v3.2
+Description: The ACPI pm_profile sysfs interface exports the platform
+ power management (and performance) requirement expectations
+ as provided by BIOS. The integer value is directly passed as
+ retrieved from the FADT ACPI table.
+Values: For possible values see ACPI specification:
+ 5.2.9 Fixed ACPI Description Table (FADT)
+ Field: Preferred_PM_Profile
+ Currently these values are defined by spec:
+ 0 Unspecified
+ 1 Desktop
+ 2 Mobile
+ 3 Workstation
+ 4 Enterprise Server
+ 5 SOHO Server
+ 6 Appliance PC
+ 7 Performance Server
+ >7 Reserved