clk: actions: Add mux clock support

Add support for Actions Semi mux clock together with helper
functions to be used in composite clock.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/drivers/clk/actions/owl-mux.c b/drivers/clk/actions/owl-mux.c
new file mode 100644
index 000000000000..f9c6cf2540e4
--- /dev/null
+++ b/drivers/clk/actions/owl-mux.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// OWL mux clock driver
+//
+// Copyright (c) 2014 Actions Semi Inc.
+// Author: David Liu <liuwei@actions-semi.com>
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+
+#include "owl-mux.h"
+
+u8 owl_mux_helper_get_parent(const struct owl_clk_common *common,
+			     const struct owl_mux_hw *mux_hw)
+{
+	u32 reg;
+	u8 parent;
+
+	regmap_read(common->regmap, mux_hw->reg, &reg);
+	parent = reg >> mux_hw->shift;
+	parent &= BIT(mux_hw->width) - 1;
+
+	return parent;
+}
+
+static u8 owl_mux_get_parent(struct clk_hw *hw)
+{
+	struct owl_mux *mux = hw_to_owl_mux(hw);
+
+	return owl_mux_helper_get_parent(&mux->common, &mux->mux_hw);
+}
+
+int owl_mux_helper_set_parent(const struct owl_clk_common *common,
+			      struct owl_mux_hw *mux_hw, u8 index)
+{
+	u32 reg;
+
+	regmap_read(common->regmap, mux_hw->reg, &reg);
+	reg &= ~GENMASK(mux_hw->width + mux_hw->shift - 1, mux_hw->shift);
+	regmap_write(common->regmap, mux_hw->reg,
+			reg | (index << mux_hw->shift));
+
+	return 0;
+}
+
+static int owl_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct owl_mux *mux = hw_to_owl_mux(hw);
+
+	return owl_mux_helper_set_parent(&mux->common, &mux->mux_hw, index);
+}
+
+const struct clk_ops owl_mux_ops = {
+	.get_parent = owl_mux_get_parent,
+	.set_parent = owl_mux_set_parent,
+	.determine_rate = __clk_mux_determine_rate,
+};