Commit 71a2f115 authored by Kuninori Morimoto's avatar Kuninori Morimoto Committed by Stephen Boyd

clk: add devm_get_clk_from_child() API

Some driver is using this type of DT bindings for clock (more detail,
see ${LINUX}/Documentation/devicetree/bindings/sound/simple-card.txt).

	sound_soc {
		...
		cpu {
			clocks = <&xxx>;
			...
		};
		codec {
			clocks = <&xxx>;
			...
		};
	};

Current driver in this case uses of_clk_get() for each node, but there
is no devm_of_clk_get() today.
OTOH, the problem of having devm_of_clk_get() is that it encourages the
use of of_clk_get() when clk_get() is more desirable.

Thus, this patch adds new devm_get_clk_from_chile() which explicitly
reads as get a clock from a child node of this device.
By this function, we can also use this type of DT bindings

	sound_soc {
		clocks = <&xxx>, <&xxx>;
		clock-names = "cpu", "codec";
		clock-ranges;
		...
		cpu {
			...
		};
		codec {
			...
		};
	};
Signed-off-by: default avatarKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[sboyd@codeurora.org: Rename subject to clk + add API]
Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
parent 16cd7764
......@@ -53,3 +53,24 @@ void devm_clk_put(struct device *dev, struct clk *clk)
WARN_ON(ret);
}
EXPORT_SYMBOL(devm_clk_put);
struct clk *devm_get_clk_from_child(struct device *dev,
struct device_node *np, const char *con_id)
{
struct clk **ptr, *clk;
ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
clk = of_clk_get_by_name(np, con_id);
if (!IS_ERR(clk)) {
*ptr = clk;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return clk;
}
EXPORT_SYMBOL(devm_get_clk_from_child);
......@@ -17,8 +17,9 @@
#include <linux/notifier.h>
struct device;
struct clk;
struct device_node;
struct of_phandle_args;
/**
* DOC: clk notifier callback types
......@@ -248,6 +249,23 @@ struct clk *clk_get(struct device *dev, const char *id);
*/
struct clk *devm_clk_get(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"
* @np: pointer to clock consumer node
* @con_id: clock consumer ID
*
* This function parses the clocks, and uses them to look up the
* struct clk from the registered list of clock providers by using
* @np and @con_id
*
* The clock will automatically be freed when the device is unbound
* from the bus.
*/
struct clk *devm_get_clk_from_child(struct device *dev,
struct device_node *np, const char *con_id);
/**
* clk_enable - inform the system when the clock source should be running.
* @clk: clock source
......@@ -432,6 +450,12 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id)
return NULL;
}
static inline struct clk *devm_get_clk_from_child(struct device *dev,
struct device_node *np, const char *con_id)
{
return NULL;
}
static inline void clk_put(struct clk *clk) {}
static inline void devm_clk_put(struct device *dev, struct clk *clk) {}
......@@ -501,9 +525,6 @@ static inline void clk_disable_unprepare(struct clk *clk)
clk_unprepare(clk);
}
struct device_node;
struct of_phandle_args;
#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
struct clk *of_clk_get(struct device_node *np, int index);
struct clk *of_clk_get_by_name(struct device_node *np, const char *name);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment