[PATCH 1/9] PM / devfreq: Add devfreq_get_devfreq_by_node function

Chanwoo Choi
2019-12-17T05:51:53Z

From: Leonard Crestez <leonard.crestez@nxp.com>

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.

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>
---
drivers/devfreq/devfreq.c | 46 +++++++++++++++++++++++++++++----------
include/linux/devfreq.h | 6 +++++
2 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 89260b17598f..cb8ca81c8973 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -966,6 +966,32 @@ 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
@@ -988,26 +1014,24 @@ 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 c6f82d4bec9f..e3633ae43349 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -253,6 +253,7 @@ extern void devm_devfreq_unregister_notifier(struct device *dev,
struct devfreq *devfreq,
struct notifier_block *nb,
unsigned int list);
+extern struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
int index);

@@ -407,6 +408,11 @@ static inline void devm_devfreq_unregister_notifier(struct device *dev,
{
}

+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)
{
--
2.17.1