Behaves the same as (devm_)clk_get except where there is no clock
producer. In this case, instead of returning -ENOENT, the function
returns NULL. This makes error checking simpler and allows
clk_prepare_enable, etc to be called on the returned reference
without additional checks.
Signed-off-by: Phil Edworthy <phil.edwor...@renesas.com>
---
v5:
- No changes.
v4:
- No changes.
v3:
- No changes.
---
drivers/clk/clk-devres.c | 18 ++++++++++++++++--
drivers/clk/clkdev.c | 17 +++++++++++++++--
include/linux/clk.h | 29 +++++++++++++++++++++++++++++
3 files changed, 60 insertions(+), 4 deletions(-)
diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index d854e26..a2bb01a 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -14,7 +14,7 @@ static void devm_clk_release(struct device *dev, void *res)
clk_put(*(struct clk **)res);
}
-struct clk *devm_clk_get(struct device *dev, const char *id)
+static struct clk *__devm_clk_get(struct device *dev, const char *id, bool
optional)
{
struct clk **ptr, *clk;
@@ -22,7 +22,10 @@ struct clk *devm_clk_get(struct device *dev, const char *id)
if (!ptr)
return ERR_PTR(-ENOMEM);
- clk = clk_get(dev, id);
+ if (!optional)
+ clk = clk_get(dev, id);
+ else
+ clk = clk_get_optional(dev, id);
if (!IS_ERR(clk)) {
*ptr = clk;
devres_add(dev, ptr);
@@ -32,8 +35,19 @@ struct clk *devm_clk_get(struct device *dev, const char *id)
return clk;
}
+
+struct clk *devm_clk_get(struct device *dev, const char *id)
+{
+ return __devm_clk_get(dev, id, false);
+}
EXPORT_SYMBOL(devm_clk_get);
+struct clk *devm_clk_get_optional(struct device *dev, const char *id)
+{
+ return __devm_clk_get(dev, id, true);
+}
+EXPORT_SYMBOL(devm_clk_get_optional);
+
struct clk_bulk_devres {
struct clk_bulk_data *clks;
int num_clks;
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 4adb99e..6355573 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -222,21 +222,34 @@ struct clk *clk_get_sys(const char *dev_id, const char
*con_id)
}
EXPORT_SYMBOL(clk_get_sys);
-struct clk *clk_get(struct device *dev, const char *con_id)
+static struct clk *internal_clk_get(struct device *dev, const char *con_id,
+ bool optional)
{
const char *dev_id = dev ? dev_name(dev) : NULL;
struct clk *clk;
if (dev && dev->of_node) {
- clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id, false);
+ clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id,
+ optional);
if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER)
return clk;
}
return clk_get_sys(dev_id, con_id);
}
+
+struct clk *clk_get(struct device *dev, const char *con_id)
+{
+ return internal_clk_get(dev, con_id, false);
+}
EXPORT_SYMBOL(clk_get);
+struct clk *clk_get_optional(struct device *dev, const char *con_id)
+{
+ return internal_clk_get(dev, con_id, true);
+}
+EXPORT_SYMBOL(clk_get_optional);
+
void clk_put(struct clk *clk)
{
__clk_put(clk);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index de0e5e0..58ec7bc 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -291,6 +291,16 @@ static inline void clk_bulk_unprepare(int num_clks, struct
clk_bulk_data *clks)
struct clk *clk_get(struct device *dev, const char *id);
/**
+ * clk_get_optional - lookup and obtain a reference to optional clock producer.
+ * @dev: device for clock "consumer"
+ * @id: clock consumer ID
+ *
+ * Behaves the same as clk_get except where there is no clock producer. In this
+ * case, instead of returning -ENOENT, the function returns NULL.
+ */
+struct clk *clk_get_optional(struct device *dev, const char *id);
+
+/**
* clk_bulk_get - lookup and obtain a number of references to clock producer.
* @dev: device for clock "consumer"
* @num_clks: the number of clk_bulk_data
@@ -349,6 +359,14 @@ int __must_check devm_clk_bulk_get(struct device *dev, int
num_clks,
struct clk *devm_clk_get(struct device *dev, const char *id);
/**
+ * devm_clk_get_optional - lookup and obtain a managed reference to an optional
+ * clock producer.
+ * Behaves the same as devm_clk_get except where there is no clock producer. In
+ * this case, instead of returning -ENOENT, the function returns NULL.
+ */
+struct clk *devm_clk_get_optional(struct device *dev, const char *id);
+
+/**
* devm_get_clk_from_child - lookup and obtain a managed reference to a
* clock producer from child node.
* @dev: device for clock "consumer"
@@ -636,6 +654,11 @@ static inline struct clk *clk_get(struct device *dev,
const char *id)
return NULL;
}
+static inline struct clk *clk_get_optional(struct device *dev, const char *id)
+{
+ return NULL;
+}
+
static inline int __must_check clk_bulk_get(struct device *dev, int num_clks,
struct clk_bulk_data *clks)
{
@@ -647,6 +670,12 @@ static inline struct clk *devm_clk_get(struct device *dev,
const char *id)
return NULL;
}
+static inline struct clk *devm_clk_get_optional(struct device *dev,
+ const char *id)
+{
+ return NULL;
+}
+
static inline int __must_check devm_clk_bulk_get(struct device *dev, int
num_clks,
struct clk_bulk_data *clks)
{
--
2.7.4
