clk: actions: Add divider clock support

Add support for Actions Semi divider 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, 94 insertions, 0 deletions

diff --git a/drivers/clk/actions/owl-divider.c b/drivers/clk/actions/owl-divider.c
new file mode 100644
index 000000000000..cddac00fe324
--- /dev/null
+++ b/drivers/clk/actions/owl-divider.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// OWL divider 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-divider.h"
+
+long owl_divider_helper_round_rate(struct owl_clk_common *common,
+				const struct owl_divider_hw *div_hw,
+				unsigned long rate,
+				unsigned long *parent_rate)
+{
+	return divider_round_rate(&common->hw, rate, parent_rate,
+				  div_hw->table, div_hw->width,
+				  div_hw->div_flags);
+}
+
+static long owl_divider_round_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long *parent_rate)
+{
+	struct owl_divider *div = hw_to_owl_divider(hw);
+
+	return owl_divider_helper_round_rate(&div->common, &div->div_hw,
+					     rate, parent_rate);
+}
+
+unsigned long owl_divider_helper_recalc_rate(struct owl_clk_common *common,
+					 const struct owl_divider_hw *div_hw,
+					 unsigned long parent_rate)
+{
+	unsigned long val;
+	unsigned int reg;
+
+	regmap_read(common->regmap, div_hw->reg, &reg);
+	val = reg >> div_hw->shift;
+	val &= (1 << div_hw->width) - 1;
+
+	return divider_recalc_rate(&common->hw, parent_rate,
+				   val, div_hw->table,
+				   div_hw->div_flags,
+				   div_hw->width);
+}
+
+static unsigned long owl_divider_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	struct owl_divider *div = hw_to_owl_divider(hw);
+
+	return owl_divider_helper_recalc_rate(&div->common,
+					      &div->div_hw, parent_rate);
+}
+
+int owl_divider_helper_set_rate(const struct owl_clk_common *common,
+				const struct owl_divider_hw *div_hw,
+				unsigned long rate,
+				unsigned long parent_rate)
+{
+	unsigned long val;
+	unsigned int reg;
+
+	val = divider_get_val(rate, parent_rate, div_hw->table,
+			      div_hw->width, 0);
+
+	regmap_read(common->regmap, div_hw->reg, &reg);
+	reg &= ~GENMASK(div_hw->width + div_hw->shift - 1, div_hw->shift);
+
+	regmap_write(common->regmap, div_hw->reg,
+			  reg | (val << div_hw->shift));
+
+	return 0;
+}
+
+static int owl_divider_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	struct owl_divider *div = hw_to_owl_divider(hw);
+
+	return owl_divider_helper_set_rate(&div->common, &div->div_hw,
+					rate, parent_rate);
+}
+
+const struct clk_ops owl_divider_ops = {
+	.recalc_rate = owl_divider_recalc_rate,
+	.round_rate = owl_divider_round_rate,
+	.set_rate = owl_divider_set_rate,
+};