[CPUFREQ] Documentation: ABI: /sys/devices/system/cpu/cpu#/cpufreq/

This is a complex interface and is already described in
Documentation/cpu-freq/, especially in the user-guide.txt file.

No need to copy/paste all that information. Let's just alert the reader
to the presence of the user-guide.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index a703b9e9aeb9d778b6591b066abb210811234705..974e29f5da86175e204ab473927e222102adbc2f 100644 (file)
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -136,6 +136,24 @@ Description:       Discover cpuidle policy and mechanism
                See files in Documentation/cpuidle/ for more information.
 
 
+What:          /sys/devices/system/cpu/cpu#/cpufreq/*
+Date:          pre-git history
+Contact:       cpufreq@vger.kernel.org
+Description:   Discover and change clock speed of CPUs
+
+               Clock scaling allows you to change the clock speed of the
+               CPUs on the fly. This is a nice method to save battery
+               power, because the lower the clock speed, the less power
+               the CPU consumes.
+
+               There are many knobs to tweak in this directory.
+
+               See files in Documentation/cpu-freq/ for more information.
+
+               In particular, read Documentation/cpu-freq/user-guide.txt
+               to learn how to control the knobs.
+
+
 What:      /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
 Date:      August 2008
 KernelVersion: 2.6.27