clk: add clk_set_parent()

Clocks may support multiple parents: this change introduces an
optional operation on the clk-uclass to set a clock's parent.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: David Wu <david.wu@rock-chips.com>

Series-changes: 2
- Fixed David's email address.

1 files changed, 11 insertions, 0 deletions

diff --git a/include/clk.h b/include/clk.h
index e7ce3e8576..e463d8e60d 100644
--- a/include/clk.h
+++ b/include/clk.h
@@ -178,6 +178,17 @@ ulong clk_get_rate(struct clk *clk);
 ulong clk_set_rate(struct clk *clk, ulong rate);
 
 /**
+ * clk_set_parent() - Set current clock parent.
+ *
+ * @clk:	A clock struct that was previously successfully requested by
+ *		clk_request/get_by_*().
+ * @parent:	A clock struct that was previously successfully requested by
+ *		clk_request/get_by_*().
+ * @return new rate, or -ve error code.
+ */
+int clk_set_parent(struct clk *clk, struct clk *parent);
+
+/**
  * clk_enable() - Enable (turn on) a clock.
  *
  * @clk:	A clock struct that was previously successfully requested by