clk: sunxi-ng: Allow muxes to have keys

Signed-off-by: Samuel Holland <samuel@sholland.org>

drivers/clk/sunxi-ng/ccu_common.h

@@ -17,6 +17,7 @@
 #define CCU_FEATURE_LOCK_REG		BIT(5)
 #define CCU_FEATURE_MMC_TIMING_SWITCH	BIT(6)
 #define CCU_FEATURE_SIGMA_DELTA_MOD	BIT(7)
+#define CCU_FEATURE_KEY_FIELD		BIT(8)
 
 /* MMC timing mode switch bit */
 #define CCU_MMC_NEW_TIMING_MODE		BIT(30)

drivers/clk/sunxi-ng/ccu_mux.c

@@ -12,6 +12,8 @@
 #include "ccu_gate.h"
 #include "ccu_mux.h"
 
+#define CCU_MUX_KEY_VALUE		0x16aa0000
+
 static u16 ccu_mux_get_prediv(struct ccu_common *common,
 			      struct ccu_mux_internal *cm,
 			      int parent_index)
@@ -188,6 +190,11 @@ int ccu_mux_helper_set_parent(struct ccu_common *common,
 	spin_lock_irqsave(common->lock, flags);
 
 	reg = readl(common->base + common->reg);
+
+	/* The key field always reads as zero. */
+	if (common->features & CCU_FEATURE_KEY_FIELD)
+		reg |= CCU_MUX_KEY_VALUE;
+
 	reg &= ~GENMASK(cm->width + cm->shift - 1, cm->shift);
 	writel(reg | (index << cm->shift), common->base + common->reg);
 

drivers/clk/sunxi-ng/ccu_mux.h

@@ -72,6 +72,20 @@ struct ccu_mux {
 	SUNXI_CCU_MUX_TABLE_WITH_GATE(_struct, _name, _parents, NULL,	\
 				      _reg, _shift, _width, 0, _flags)
 
+#define SUNXI_CCU_MUX_HW_WITH_KEY(_struct, _name, _parents, _reg,	\
+				  _shift, _width, _key, _flags)		\
+	struct ccu_mux _struct = {					\
+		.mux	= _SUNXI_CCU_MUX(_shift, _width),		\
+		.common	= {						\
+			.reg		= _reg,				\
+			.features	= CCU_FEATURE_KEY_FIELD,	\
+			.hw.init	= CLK_HW_INIT_PARENTS_HW(_name,	\
+								 _parents, \
+								 &ccu_mux_ops, \
+								 _flags), \
+		}							\
+	}
+
 static inline struct ccu_mux *hw_to_ccu_mux(struct clk_hw *hw)
 {
 	struct ccu_common *common = hw_to_ccu_common(hw);