[U-Boot] [PATCH V3 03/16] clk: mux: add set parent support

Peng Fan peng.fan at nxp.com
Wed Jul 31 07:01:28 UTC 2019


Add set parent support for clk mux

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

V3:
 None
V2:
 Rebase

 drivers/clk/clk-mux.c        | 70 ++++++++++++++++++++++++++++++++++++++++++--
 include/linux/clk-provider.h |  2 ++
 2 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 81d1e7ebee..5acc0b8cbd 100644
--- a/drivers/clk/clk-mux.c
+++ b/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,
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 43a25e9c6a..7e44045c16 100644
--- a/include/linux/clk-provider.h
+++ b/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;
-- 
2.16.4



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