PM / devfreq: provide hooks for governors to be registered

Add devfreq_add_governor and devfreq_remove_governor which
can be invoked by governors to register with devfreq.

This sets up the stage to dynamically switch governors and
allow governors to be dynamically loaded as well.

Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kevin Hilman <khilman@ti.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index bc35c4aee6a3..6484a3f8dda8 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -92,6 +92,7 @@ struct devfreq_dev_profile {
 
 /**
  * struct devfreq_governor - Devfreq policy governor
+ * @node:               list node - contains registered devfreq governors
  * @name:               Governor's name
  * @get_target_freq:    Returns desired operating frequency for the device.
  *                      Basically, get_target_freq will run
@@ -107,6 +108,8 @@ struct devfreq_dev_profile {
  * Note that the callbacks are called with devfreq->lock locked by devfreq.
  */
 struct devfreq_governor {
+        struct list_head node;
+
         const char name[DEVFREQ_NAME_LEN];
         int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
         int (*event_handler)(struct devfreq *devfreq,