[PATCH] clk: mediatek: fixed static checker warning in clk_cpumux_get_parent call

[sean.wang]

From: Sean Wang <sean.w...@mediatek.com>

Fixed the signedness bug returning '(-22)' on the return type as u8 with
moving the sanity checker into clk_cpumux_set_parent() to ensure always
validity in clk_cpumux_get_parent() got called.

Fixes: commit 1e17de9049da ("clk: mediatek: add missing cpu mux causing 
Mediatek cpufreq can't work")
Reported-by: Dan Carpenter <dan.carpen...@oracle.com>
Signed-off-by: Sean Wang <sean.w...@mediatek.com>
---
 drivers/clk/mediatek/clk-cpumux.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/mediatek/clk-cpumux.c 
b/drivers/clk/mediatek/clk-cpumux.c
index edd8e69..c6a3a1a 100644
--- a/drivers/clk/mediatek/clk-cpumux.c
+++ b/drivers/clk/mediatek/clk-cpumux.c
@@ -27,7 +27,6 @@ static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct 
clk_hw *_hw)
 static u8 clk_cpumux_get_parent(struct clk_hw *hw)
 {
        struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
-       int num_parents = clk_hw_get_num_parents(hw);
        unsigned int val;
 
        regmap_read(mux->regmap, mux->reg, &val);
@@ -35,17 +34,18 @@ static u8 clk_cpumux_get_parent(struct clk_hw *hw)
        val >>= mux->shift;
        val &= mux->mask;
 
-       if (val >= num_parents)
-               return -EINVAL;
-
        return val;
 }
 
 static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
 {
        struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
+       int num_parents = clk_hw_get_num_parents(hw);
        u32 mask, val;
 
+       if (index >= num_parents)
+               return -EINVAL;
+
        val = index << mux->shift;
        mask = mux->mask << mux->shift;
 
-- 
2.7.4