clk: mux: add explicit big endian support

Add a clock specific flag to switch register accesses to big endian, to
allow runtime configuration of big endian mux clocks.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 2ad2df2..61ad331 100644
--- a/drivers/clk/clk-mux.c
+++ b/drivers/clk/clk-mux.c
@@ -23,6 +23,22 @@
  * parent - parent is adjustable through clk_set_parent
  */
 
+static inline u32 clk_mux_readl(struct clk_mux *mux)
+{
+	if (mux->flags & CLK_MUX_BIG_ENDIAN)
+		return ioread32be(mux->reg);
+
+	return clk_readl(mux->reg);
+}
+
+static inline void clk_mux_writel(struct clk_mux *mux, u32 val)
+{
+	if (mux->flags & CLK_MUX_BIG_ENDIAN)
+		iowrite32be(val, mux->reg);
+	else
+		clk_writel(val, mux->reg);
+}
+
 int clk_mux_val_to_index(struct clk_hw *hw, u32 *table, unsigned int flags,
 			 unsigned int val)
 {
@@ -73,7 +89,7 @@ static u8 clk_mux_get_parent(struct clk_hw *hw)
 	struct clk_mux *mux = to_clk_mux(hw);
 	u32 val;
 
-	val = clk_readl(mux->reg) >> mux->shift;
+	val = clk_mux_readl(mux) >> mux->shift;
 	val &= mux->mask;
 
 	return clk_mux_val_to_index(hw, mux->table, mux->flags, val);
@@ -94,12 +110,12 @@ static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
 	if (mux->flags & CLK_MUX_HIWORD_MASK) {
 		reg = mux->mask << (mux->shift + 16);
 	} else {
-		reg = clk_readl(mux->reg);
+		reg = clk_mux_readl(mux);
 		reg &= ~(mux->mask << mux->shift);
 	}
 	val = val << mux->shift;
 	reg |= val;
-	clk_writel(reg, mux->reg);
+	clk_mux_writel(mux, reg);
 
 	if (mux->lock)
 		spin_unlock_irqrestore(mux->lock, flags);