PM / devfreq: add comments and Documentation

- Added missing ABI documents
- Added comments to clarify the objectives of functions

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Rajagopal Venkat <rajagopal.venkat@linaro.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq
index 0ba6ea2f89d9..ee39acacf6f8 100644
--- a/Documentation/ABI/testing/sysfs-class-devfreq
+++ b/Documentation/ABI/testing/sysfs-class-devfreq
@@ -78,3 +78,23 @@ Contact:	Nishanth Menon <nm@ti.com>
 Description:
                 The /sys/class/devfreq/.../available_governors shows
                 currently available governors in the system.
+
+What:           /sys/class/devfreq/.../min_freq
+Date:           January 2013
+Contact:        MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+                The /sys/class/devfreq/.../min_freq shows and stores
+                the minimum frequency requested by users. It is 0 if
+                the user does not care. min_freq overrides the
+                frequency requested by governors.
+
+What:           /sys/class/devfreq/.../max_freq
+Date:           January 2013
+Contact:        MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+                The /sys/class/devfreq/.../max_freq shows and stores
+                the maximum frequency requested by users. It is 0 if
+                the user does not care. max_freq overrides the
+                frequency requested by governors and min_freq.
+                The max_freq overrides min_freq because max_freq may be
+                used to throttle devices to avoid overheating.