clk: gate: add CLK_GATE_HIWORD_MASK

In Rockchip Cortex-A9 based chips, they don't use paradigm of
reading-changing-writing the register contents.  Instead they
use a hiword mask to indicate the changed bits.

When b1 should be set as gate, it also needs to indicate the change
by setting hiword mask (b1 << 16).

The patch adds gate flag for this usage.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index d77f126..1ec14a7 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -210,6 +210,10 @@
  * CLK_GATE_SET_TO_DISABLE - by default this clock sets the bit at bit_idx to
  * 	enable the clock.  Setting this flag does the opposite: setting the bit
  * 	disable the clock and clearing it enables the clock
+ * CLK_GATE_HIWORD_MASK - The gate settings are only in lower 16-bit
+ *   of this register, and mask of gate bits are in higher 16-bit of this
+ *   register.  While setting the gate bits, higher 16-bit should also be
+ *   updated to indicate changing gate bits.
  */
 struct clk_gate {
 	struct clk_hw hw;
@@ -220,6 +224,7 @@
 };
 
 #define CLK_GATE_SET_TO_DISABLE		BIT(0)
+#define CLK_GATE_HIWORD_MASK		BIT(1)
 
 extern const struct clk_ops clk_gate_ops;
 struct clk *clk_register_gate(struct device *dev, const char *name,