clk: sunxi: Implement MMC phase control

HdG: add header exporting clk_sunxi_mmc_phase_control

Signed-off-by: Emilio López <emilio@elopez.com.ar>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index bd7dc73..59f9040 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -507,6 +507,42 @@
 
 
 /**
+ * clk_sunxi_mmc_phase_control() - configures MMC clock phase control
+ */
+
+void clk_sunxi_mmc_phase_control(struct clk_hw *hw, u8 sample, u8 output)
+{
+	#define to_clk_composite(_hw) container_of(_hw, struct clk_composite, hw)
+	#define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw)
+
+	struct clk_composite *composite = to_clk_composite(hw);
+	struct clk_hw *rate_hw = composite->rate_hw;
+	struct clk_factors *factors = to_clk_factors(rate_hw);
+	unsigned long flags = 0;
+	u32 reg;
+
+	if (factors->lock)
+		spin_lock_irqsave(factors->lock, flags);
+
+	reg = readl(factors->reg);
+
+	/* set sample clock phase control */
+	reg &= ~(0x7 << 20);
+	reg |= ((sample & 0x7) << 20);
+
+	/* set output clock phase control */
+	reg &= ~(0x7 << 8);
+	reg |= ((output & 0x7) << 8);
+
+	writel(reg, factors->reg);
+
+	if (factors->lock)
+		spin_unlock_irqrestore(factors->lock, flags);
+}
+EXPORT_SYMBOL(clk_sunxi_mmc_phase_control);
+
+
+/**
  * sunxi_factors_clk_setup() - Setup function for factor clocks
  */