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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/clk/at91/clk-h32mx.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--drivers/clk/at91/clk-h32mx.c125
1 files changed, 125 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..e0daa4a31
--- /dev/null
+++ b/drivers/clk/at91/clk-h32mx.c
@@ -0,0 +1,125 @@
+/*
+ * clk-h32mx.c
+ *
+ * Copyright (C) 2014 Atmel
+ *
+ * Alexandre Belloni <alexandre.belloni@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/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,
+};
+
+static void __init of_sama5d4_clk_h32mx_setup(struct device_node *np)
+{
+ struct clk_sama5d4_h32mx *h32mxclk;
+ struct clk_init_data init;
+ const char *parent_name;
+ struct regmap *regmap;
+ int ret;
+
+ regmap = syscon_node_to_regmap(of_get_parent(np));
+ if (IS_ERR(regmap))
+ return;
+
+ h32mxclk = kzalloc(sizeof(*h32mxclk), GFP_KERNEL);
+ if (!h32mxclk)
+ return;
+
+ parent_name = of_clk_get_parent_name(np, 0);
+
+ init.name = np->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;
+ }
+
+ of_clk_add_hw_provider(np, of_clk_hw_simple_get, &h32mxclk->hw);
+}
+CLK_OF_DECLARE(of_sama5d4_clk_h32mx_setup, "atmel,sama5d4-clk-h32mx",
+ of_sama5d4_clk_h32mx_setup);