PM / devfreq: Add devfreq_get_devfreq_by_phandle()

This patch adds the new devfreq_get_devfreq_by_phandle() OF helper function
which can find the instance of devfreq device by using phandle ("devfreq").

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
[m.reichl and linux.amoon: Tested it on exynos4412-odroidu3 board]
Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 6fa02a20eb63..aa0b8424ebc3 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -208,6 +208,9 @@ extern int devm_devfreq_register_opp_notifier(struct device *dev,
 extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
                                                 struct devfreq *devfreq);
 
+extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
+                                                int index);
+
 /**
  * devfreq_update_stats() - update the last_status pointer in struct devfreq
  * @df:         the devfreq instance whose status needs updating
@@ -307,6 +310,12 @@ static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
 {
 }
 
+static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
+                                                        int index)
+{
+        return ERR_PTR(-ENODEV);
+}
+
 static inline int devfreq_update_stats(struct devfreq *df)
 {
         return -EINVAL;