pwm: Add devm_of_pwm_get() as exported API for users

When booted with DT users can use devm version of of_pwm_get() to benefit
from automatic resource release.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 76a1959..70655a2 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -179,6 +179,8 @@
 void pwm_put(struct pwm_device *pwm);
 
 struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id);
+struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
+				   const char *con_id);
 void devm_pwm_put(struct device *dev, struct pwm_device *pwm);
 #else
 static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data)
@@ -230,6 +232,13 @@
 	return ERR_PTR(-ENODEV);
 }
 
+static inline struct pwm_device *devm_of_pwm_get(struct device *dev,
+						 struct device_node *np,
+						 const char *con_id)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
 {
 }