PM / devfreq: Add current freq callback in device profile

Devfreq returns governor predicted frequency as current frequency
via sysfs interface. But device may not support all frequencies
that governor predicts. So add a callback in device profile to get
current freq from driver. Also add a new sysfs node to expose
governor predicted next target frequency.

Signed-off-by: Rajagopal Venkat <rajagopal.venkat@linaro.org>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq
index 89283b1..e6cf08e 100644
--- a/Documentation/ABI/testing/sysfs-class-devfreq
+++ b/Documentation/ABI/testing/sysfs-class-devfreq
@@ -19,7 +19,16 @@
 Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 Description:
 		The /sys/class/devfreq/.../cur_freq shows the current
-		frequency of the corresponding devfreq object.
+		frequency of the corresponding devfreq object. Same as
+		target_freq when get_cur_freq() is not implemented by
+		devfreq driver.
+
+What:		/sys/class/devfreq/.../target_freq
+Date:		September 2012
+Contact:	Rajagopal Venkat <rajagopal.venkat@linaro.org>
+Description:
+		The /sys/class/devfreq/.../target_freq shows the next governor
+		predicted target frequency of the corresponding devfreq object.
 
 What:		/sys/class/devfreq/.../polling_interval
 Date:		September 2011