1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-plldiv.c b/drivers/clk/at91/clk-plldiv.c
new file mode 100644
index 000000000000..3ac09fecc54e
--- /dev/null
+++ b/drivers/clk/at91/clk-plldiv.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+#define to_clk_plldiv(hw) container_of(hw, struct clk_plldiv, hw)
+
+struct clk_plldiv {
+	struct clk_hw hw;
+	struct regmap *regmap;
+};
+
+static unsigned long clk_plldiv_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct clk_plldiv *plldiv = to_clk_plldiv(hw);
+	unsigned int mckr;
+
+	regmap_read(plldiv->regmap, AT91_PMC_MCKR, &mckr);
+
+	if (mckr & AT91_PMC_PLLADIV2)
+		return parent_rate / 2;
+
+	return parent_rate;
+}
+
+static int clk_plldiv_determine_rate(struct clk_hw *hw,
+				     struct clk_rate_request *req)
+{
+	unsigned long div;
+
+	if (req->rate > req->best_parent_rate) {
+		req->rate = req->best_parent_rate;
+
+		return 0;
+	}
+
+	div = req->best_parent_rate / 2;
+	if (req->rate < div) {
+		req->rate = div;
+
+		return 0;
+	}
+
+	if (req->rate - div < req->best_parent_rate - req->rate) {
+		req->rate = div;
+
+		return 0;
+	}
+
+	req->rate = req->best_parent_rate;
+
+	return 0;
+}
+
+static int clk_plldiv_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct clk_plldiv *plldiv = to_clk_plldiv(hw);
+
+	if ((parent_rate != rate) && (parent_rate / 2 != rate))
+		return -EINVAL;
+
+	regmap_update_bits(plldiv->regmap, AT91_PMC_MCKR, AT91_PMC_PLLADIV2,
+			   parent_rate != rate ? AT91_PMC_PLLADIV2 : 0);
+
+	return 0;
+}
+
+static const struct clk_ops plldiv_ops = {
+	.recalc_rate = clk_plldiv_recalc_rate,
+	.determine_rate = clk_plldiv_determine_rate,
+	.set_rate = clk_plldiv_set_rate,
+};
+
+struct clk_hw * __init
+at91_clk_register_plldiv(struct regmap *regmap, const char *name,
+			 const char *parent_name)
+{
+	struct clk_plldiv *plldiv;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	plldiv = kzalloc(sizeof(*plldiv), GFP_KERNEL);
+	if (!plldiv)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &plldiv_ops;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+	init.flags = CLK_SET_RATE_GATE;
+
+	plldiv->hw.init = &init;
+	plldiv->regmap = regmap;
+
+	hw = &plldiv->hw;
+	ret = clk_hw_register(NULL, &plldiv->hw);
+	if (ret) {
+		kfree(plldiv);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}