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: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
[sboyd@codeurora.org: Rename subject to clk + add API]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index 8f57154..3a218c3 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -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);