clk: mux: add set parent support

Add set parent support for clk mux

Signed-off-by: Peng Fan <peng.fan@nxp.com>

drivers/clk/clk-mux.c

@@ -60,7 +60,24 @@ int clk_mux_val_to_index(struct clk *clk, u32 *table, unsigned int flags,
 	return val;
 }
 
-static u8 clk_mux_get_parent(struct clk *clk)
+unsigned int clk_mux_index_to_val(u32 *table, unsigned int flags, u8 index)
+{
+	unsigned int val = index;
+
+	if (table) {
+		val = table[index];
+	} else {
+		if (flags & CLK_MUX_INDEX_BIT)
+			val = 1 << index;
+
+		if (flags & CLK_MUX_INDEX_ONE)
+			val++;
+	}
+
+	return val;
+}
+
+u8 clk_mux_get_parent(struct clk *clk)
 {
 	struct clk_mux *mux = to_clk_mux(clk_dev_binded(clk) ?
 			dev_get_clk_ptr(clk->dev) : clk);
@@ -77,8 +94,57 @@ static u8 clk_mux_get_parent(struct clk *clk)
 	return clk_mux_val_to_index(clk, mux->table, mux->flags, val);
 }
 
+static int clk_fetch_parent_index(struct clk *clk,
+				  struct clk *parent)
+{
+	struct clk_mux *mux = to_clk_mux(clk_dev_binded(clk) ?
+			dev_get_clk_ptr(clk->dev) : clk);
+
+	int i;
+
+	if (!parent)
+		return -EINVAL;
+
+	for (i = 0; i < mux->num_parents; i++) {
+		if (!strcmp(parent->dev->name, mux->parent_names[i]))
+			return i;
+	}
+
+	return -EINVAL;
+}
+
+static int clk_mux_set_parent(struct clk *clk, struct clk *parent)
+{
+	struct clk_mux *mux = to_clk_mux(clk_dev_binded(clk) ?
+			dev_get_clk_ptr(clk->dev) : clk);
+	int index;
+	u32 val;
+	u32 reg;
+
+	index = clk_fetch_parent_index(clk, parent);
+	if (index < 0) {
+		printf("Could not fetch index\n");
+		return index;
+	}
+
+	val = clk_mux_index_to_val(mux->table, mux->flags, index);
+
+	if (mux->flags & CLK_MUX_HIWORD_MASK) {
+		reg = mux->mask << (mux->shift + 16);
+	} else {
+		reg = readl(mux->reg);
+		reg &= ~(mux->mask << mux->shift);
+	}
+	val = val << mux->shift;
+	reg |= val;
+	writel(reg, mux->reg);
+
+	return 0;
+}
+
 const struct clk_ops clk_mux_ops = {
-		.get_rate = clk_generic_get_rate,
+	.get_rate = clk_generic_get_rate,
+	.set_parent = clk_mux_set_parent,
 };
 
 struct clk *clk_hw_register_mux_table(struct device *dev, const char *name,

include/linux/clk-provider.h

@@ -66,6 +66,8 @@ struct clk_mux {
 };
 
 #define to_clk_mux(_clk) container_of(_clk, struct clk_mux, clk)
+extern const struct clk_ops clk_mux_ops;
+u8 clk_mux_get_parent(struct clk *clk);
 
 struct clk_div_table {
 	unsigned int	val;