PM / devfreq: Add devfreq_get_devfreq_by_node function

Split off part of devfreq_get_devfreq_by_phandle into a separate
function. This allows callers to fetch devfreq instances by enumerating
devicetree instead of explicit phandles.

Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[cw00.choi: Export devfreq_get_devfreq_by_node function and
 add function to devfreq.h when CONFIG_PM_DEVFREQ is enabled.]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 071b59fe84d2eabebcdbd2ab298c9ac3e256e8cc..d4424b5d8306068f370ddf126b048a03c8ee6e6e 100644 (file)
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -983,6 +983,32 @@ struct devfreq *devm_devfreq_add_device(struct device *dev,
 EXPORT_SYMBOL(devm_devfreq_add_device);
 
 #ifdef CONFIG_OF
+/*
+ * devfreq_get_devfreq_by_node - Get the devfreq device from devicetree
+ * @node - pointer to device_node
+ *
+ * return the instance of devfreq device
+ */
+struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
+{
+       struct devfreq *devfreq;
+
+       if (!node)
+               return ERR_PTR(-EINVAL);
+
+       mutex_lock(&devfreq_list_lock);
+       list_for_each_entry(devfreq, &devfreq_list, node) {
+               if (devfreq->dev.parent
+                       && devfreq->dev.parent->of_node == node) {
+                       mutex_unlock(&devfreq_list_lock);
+                       return devfreq;
+               }
+       }
+       mutex_unlock(&devfreq_list_lock);
+
+       return ERR_PTR(-ENODEV);
+}
+
 /*
  * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree
  * @dev - instance to the given device
@@ -1005,26 +1031,24 @@ struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
        if (!node)
                return ERR_PTR(-ENODEV);
 
-       mutex_lock(&devfreq_list_lock);
-       list_for_each_entry(devfreq, &devfreq_list, node) {
-               if (devfreq->dev.parent
-                       && devfreq->dev.parent->of_node == node) {
-                       mutex_unlock(&devfreq_list_lock);
-                       of_node_put(node);
-                       return devfreq;
-               }
-       }
-       mutex_unlock(&devfreq_list_lock);
+       devfreq = devfreq_get_devfreq_by_node(node);
        of_node_put(node);
 
-       return ERR_PTR(-EPROBE_DEFER);
+       return devfreq;
 }
+
 #else
+struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
+{
+       return ERR_PTR(-ENODEV);
+}
+
 struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index)
 {
        return ERR_PTR(-ENODEV);
 }
 #endif /* CONFIG_OF */
+EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node);
 EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle);
 
 /**

diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 12782fbb4c25ebe2f800f8cd74eb77784f30ddfd..eb971b8e5051b04e2b862f186f697721fb80a226 100644 (file)
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -261,6 +261,7 @@ void devm_devfreq_unregister_notifier(struct device *dev,
                                struct devfreq *devfreq,
                                struct notifier_block *nb,
                                unsigned int list);
+struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
 struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index);
 
 #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
@@ -414,6 +415,11 @@ static inline void devm_devfreq_unregister_notifier(struct device *dev,
 {
 }
 
+static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
+{
+       return ERR_PTR(-ENODEV);
+}
+
 static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
                                        int index)
 {