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 (file)
--- 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);

diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 0bc6d6f..4ae2257 100644 (file)
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -509,6 +509,9 @@ void clk_hw_unregister_divider(struct clk_hw *hw);
  *     indicate changing mux bits.
  * CLK_MUX_ROUND_CLOSEST - Use the parent rate that is closest to the desired
  *     frequency.
+ * CLK_MUX_BIG_ENDIAN - By default little endian register accesses are used for
+ *     the mux register.  Setting this flag makes the register accesses big
+ *     endian.
  */
 struct clk_mux {
        struct clk_hw   hw;
@@ -527,6 +530,7 @@ struct clk_mux {
 #define CLK_MUX_HIWORD_MASK            BIT(2)
 #define CLK_MUX_READ_ONLY              BIT(3) /* mux can't be changed */
 #define CLK_MUX_ROUND_CLOSEST          BIT(4)
+#define CLK_MUX_BIG_ENDIAN             BIT(5)
 
 extern const struct clk_ops clk_mux_ops;
 extern const struct clk_ops clk_mux_ro_ops;