1 files changed, 160 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sun4i/sun4i_dotclock.c b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
new file mode 100644
index 000000000000..3ff668cb463c
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
@@ -0,0 +1,160 @@
+/*
+ * Copyright (C) 2016 Free Electrons
+ * Copyright (C) 2016 NextThing Co
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+
+#include "sun4i_tcon.h"
+
+struct sun4i_dclk {
+	struct clk_hw	hw;
+	struct regmap	*regmap;
+};
+
+static inline struct sun4i_dclk *hw_to_dclk(struct clk_hw *hw)
+{
+	return container_of(hw, struct sun4i_dclk, hw);
+}
+
+static void sun4i_dclk_disable(struct clk_hw *hw)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+
+	regmap_update_bits(dclk->regmap, SUN4I_TCON0_DCLK_REG,
+			   BIT(SUN4I_TCON0_DCLK_GATE_BIT), 0);
+}
+
+static int sun4i_dclk_enable(struct clk_hw *hw)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+
+	return regmap_update_bits(dclk->regmap, SUN4I_TCON0_DCLK_REG,
+				  BIT(SUN4I_TCON0_DCLK_GATE_BIT),
+				  BIT(SUN4I_TCON0_DCLK_GATE_BIT));
+}
+
+static int sun4i_dclk_is_enabled(struct clk_hw *hw)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+	u32 val;
+
+	regmap_read(dclk->regmap, SUN4I_TCON0_DCLK_REG, &val);
+
+	return val & BIT(SUN4I_TCON0_DCLK_GATE_BIT);
+}
+
+static unsigned long sun4i_dclk_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+	u32 val;
+
+	regmap_read(dclk->regmap, SUN4I_TCON0_DCLK_REG, &val);
+
+	val >>= SUN4I_TCON0_DCLK_DIV_SHIFT;
+	val &= SUN4I_TCON0_DCLK_DIV_WIDTH;
+
+	if (!val)
+		val = 1;
+
+	return parent_rate / val;
+}
+
+static long sun4i_dclk_round_rate(struct clk_hw *hw, unsigned long rate,
+				  unsigned long *parent_rate)
+{
+	return *parent_rate / DIV_ROUND_CLOSEST(*parent_rate, rate);
+}
+
+static int sun4i_dclk_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+	int div = DIV_ROUND_CLOSEST(parent_rate, rate);
+
+	return regmap_update_bits(dclk->regmap, SUN4I_TCON0_DCLK_REG,
+				  GENMASK(6, 0), div);
+}
+
+static int sun4i_dclk_get_phase(struct clk_hw *hw)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+	u32 val;
+
+	regmap_read(dclk->regmap, SUN4I_TCON0_IO_POL_REG, &val);
+
+	val >>= 28;
+	val &= 3;
+
+	return val * 120;
+}
+
+static int sun4i_dclk_set_phase(struct clk_hw *hw, int degrees)
+{
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+
+	regmap_update_bits(dclk->regmap, SUN4I_TCON0_IO_POL_REG,
+			   GENMASK(29, 28),
+			   degrees / 120);
+
+	return 0;
+}
+
+static const struct clk_ops sun4i_dclk_ops = {
+	.disable	= sun4i_dclk_disable,
+	.enable		= sun4i_dclk_enable,
+	.is_enabled	= sun4i_dclk_is_enabled,
+
+	.recalc_rate	= sun4i_dclk_recalc_rate,
+	.round_rate	= sun4i_dclk_round_rate,
+	.set_rate	= sun4i_dclk_set_rate,
+
+	.get_phase	= sun4i_dclk_get_phase,
+	.set_phase	= sun4i_dclk_set_phase,
+};
+
+int sun4i_dclk_create(struct device *dev, struct sun4i_tcon *tcon)
+{
+	const char *clk_name, *parent_name;
+	struct clk_init_data init;
+	struct sun4i_dclk *dclk;
+
+	parent_name = __clk_get_name(tcon->sclk0);
+	of_property_read_string_index(dev->of_node, "clock-output-names", 0,
+				      &clk_name);
+
+	dclk = devm_kzalloc(dev, sizeof(*dclk), GFP_KERNEL);
+	if (!dclk)
+		return -ENOMEM;
+
+	init.name = clk_name;
+	init.ops = &sun4i_dclk_ops;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	dclk->regmap = tcon->regs;
+	dclk->hw.init = &init;
+
+	tcon->dclk = clk_register(dev, &dclk->hw);
+	if (IS_ERR(tcon->dclk))
+		return PTR_ERR(tcon->dclk);
+
+	return 0;
+}
+EXPORT_SYMBOL(sun4i_dclk_create);
+
+int sun4i_dclk_free(struct sun4i_tcon *tcon)
+{
+	clk_unregister(tcon->dclk);
+	return 0;
+}
+EXPORT_SYMBOL(sun4i_dclk_free);