1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-h32mx.c b/drivers/clk/at91/clk-h32mx.c
new file mode 100644
index 000000000..1e6c12eed
--- /dev/null
+++ b/drivers/clk/at91/clk-h32mx.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * clk-h32mx.c
+ *
+ *  Copyright (C) 2014 Atmel
+ *
+ * Alexandre Belloni <alexandre.belloni@free-electrons.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include "pmc.h"
+
+#define H32MX_MAX_FREQ	90000000
+
+struct clk_sama5d4_h32mx {
+	struct clk_hw hw;
+	struct regmap *regmap;
+};
+
+#define to_clk_sama5d4_h32mx(hw) container_of(hw, struct clk_sama5d4_h32mx, hw)
+
+static unsigned long clk_sama5d4_h32mx_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct clk_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw);
+	unsigned int mckr;
+
+	regmap_read(h32mxclk->regmap, AT91_PMC_MCKR, &mckr);
+	if (mckr & AT91_PMC_H32MXDIV)
+		return parent_rate / 2;
+
+	if (parent_rate > H32MX_MAX_FREQ)
+		pr_warn("H32MX clock is too fast\n");
+	return parent_rate;
+}
+
+static long clk_sama5d4_h32mx_round_rate(struct clk_hw *hw, unsigned long rate,
+				       unsigned long *parent_rate)
+{
+	unsigned long div;
+
+	if (rate > *parent_rate)
+		return *parent_rate;
+	div = *parent_rate / 2;
+	if (rate < div)
+		return div;
+
+	if (rate - div < *parent_rate - rate)
+		return div;
+
+	return *parent_rate;
+}
+
+static int clk_sama5d4_h32mx_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct clk_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw);
+	u32 mckr = 0;
+
+	if (parent_rate != rate && (parent_rate / 2) != rate)
+		return -EINVAL;
+
+	if ((parent_rate / 2) == rate)
+		mckr = AT91_PMC_H32MXDIV;
+
+	regmap_update_bits(h32mxclk->regmap, AT91_PMC_MCKR,
+			   AT91_PMC_H32MXDIV, mckr);
+
+	return 0;
+}
+
+static const struct clk_ops h32mx_ops = {
+	.recalc_rate = clk_sama5d4_h32mx_recalc_rate,
+	.round_rate = clk_sama5d4_h32mx_round_rate,
+	.set_rate = clk_sama5d4_h32mx_set_rate,
+};
+
+struct clk_hw * __init
+at91_clk_register_h32mx(struct regmap *regmap, const char *name,
+			const char *parent_name)
+{
+	struct clk_sama5d4_h32mx *h32mxclk;
+	struct clk_init_data init;
+	int ret;
+
+	h32mxclk = kzalloc(sizeof(*h32mxclk), GFP_KERNEL);
+	if (!h32mxclk)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &h32mx_ops;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+	init.flags = CLK_SET_RATE_GATE;
+
+	h32mxclk->hw.init = &init;
+	h32mxclk->regmap = regmap;
+
+	ret = clk_hw_register(NULL, &h32mxclk->hw);
+	if (ret) {
+		kfree(h32mxclk);
+		return ERR_PTR(ret);
+	}
+
+	return &h32mxclk->hw;
+}