[PATCH v3 4/6] OPP: Add API to find an OPP table from its DT node

Saravana Kannan
2019-07-03T01:10:42Z

This allows finding a device's OPP table (when it has multiple) from a
phandle to the OPP table in DT.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
drivers/opp/of.c | 42 ++++++++++++++++++++++++++++++++++--------
include/linux/pm_opp.h | 7 +++++++
2 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 54fa70ed2adc..34c51905f56d 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -42,14 +42,9 @@ struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
}
EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);

-struct opp_table *_managed_opp(struct device *dev, int index)
+struct opp_table *_find_opp_table_from_node(struct device_node *np)
{
struct opp_table *opp_table, *managed_table = NULL;
- struct device_node *np;
-
- np = _opp_of_get_opp_desc_node(dev->of_node, index);
- if (!np)
- return NULL;

list_for_each_entry(opp_table, &opp_tables, node) {
if (opp_table->np == np) {
@@ -69,11 +64,42 @@ struct opp_table *_managed_opp(struct device *dev, int index)
}
}

- of_node_put(np);
-
return managed_table;
}

+/**
+ * dev_pm_opp_of_find_table_from_node() - Find OPP table from its DT node
+ * @np: DT node used for finding the OPP table
+ *
+ * Return: OPP table corresponding to the DT node, else NULL on failure.
+ *
+ * The caller needs to put the node with of_node_put() after using it.
+ */
+struct opp_table *dev_pm_opp_of_find_table_from_node(struct device_node *np)
+{
+ struct opp_table *opp_table;
+
+ mutex_lock(&opp_table_lock);
+ opp_table = _find_opp_table_from_node(np);
+ mutex_unlock(&opp_table_lock);
+ return opp_table;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_table_from_node);
+
+struct opp_table *_managed_opp(struct device *dev, int index)
+{
+ struct device_node *np;
+ struct opp_table *opp_table;
+
+ np = _opp_of_get_opp_desc_node(dev->of_node, index);
+ if (!np)
+ return NULL;
+
+ opp_table = _find_opp_table_from_node(np);
+ of_node_put(np);
+ return opp_table;
+}
+
/* The caller must call dev_pm_opp_put() after the OPP is used */
static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
struct device_node *opp_np)
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index d4d79ac0b5b2..d80c59bcd50b 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -359,6 +359,7 @@ int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask);
void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask);
int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask);
struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev);
+struct opp_table *dev_pm_opp_of_find_table_from_node(struct device_node *np);
struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp);
int of_get_required_opp_performance_state(struct device_node *np, int index);
void dev_pm_opp_of_register_em(struct cpumask *cpus);
@@ -396,6 +397,12 @@ static inline struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device
return NULL;
}

+static inline struct opp_table *dev_pm_opp_of_find_table_from_node(
+ struct device_node *np)
+{
+ return NULL;
+}
+
static inline struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
{
return NULL;
--
2.22.0.410.gd8fdbe21b5-goog