clk: Add __clk_mux_determine_rate_closest

Some clock drivers want to find the closest rate on the input of
a mux instead of a rate that's less than or equal to the desired
rate. Add a generic mux function to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index ebb7055a6d84..ba858e90d5de 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -384,6 +384,8 @@ void clk_unregister_divider(struct clk *clk);
  *      register, and mask of mux bits are in higher 16-bit of this register.
  *      While setting the mux bits, higher 16-bit should also be updated to
  *      indicate changing mux bits.
+ * CLK_MUX_ROUND_CLOSEST - Use the parent rate that is closest to the desired
+ *      frequency.
  */
 struct clk_mux {
         struct clk_hw   hw;
@@ -398,7 +400,8 @@ struct clk_mux {
 #define CLK_MUX_INDEX_ONE               BIT(0)
 #define CLK_MUX_INDEX_BIT               BIT(1)
 #define CLK_MUX_HIWORD_MASK             BIT(2)
-#define CLK_MUX_READ_ONLY       BIT(3) /* mux setting cannot be changed */
+#define CLK_MUX_READ_ONLY               BIT(3) /* mux can't be changed */
+#define CLK_MUX_ROUND_CLOSEST           BIT(4)
 
 extern const struct clk_ops clk_mux_ops;
 extern const struct clk_ops clk_mux_ro_ops;
@@ -556,6 +559,9 @@ struct clk *__clk_lookup(const char *name);
 long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
                               unsigned long *best_parent_rate,
                               struct clk_hw **best_parent_p);
+long __clk_mux_determine_rate_closest(struct clk_hw *hw, unsigned long rate,
+                              unsigned long *best_parent_rate,
+                              struct clk_hw **best_parent_p);
 
 /*
  * FIXME clock api without lock protection