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path: root/drivers/clk/uniphier/clk-uniphier-cpugear.c
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Diffstat (limited to 'drivers/clk/uniphier/clk-uniphier-cpugear.c')
-rw-r--r--drivers/clk/uniphier/clk-uniphier-cpugear.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/drivers/clk/uniphier/clk-uniphier-cpugear.c b/drivers/clk/uniphier/clk-uniphier-cpugear.c
new file mode 100644
index 0000000000..a2f01a4da1
--- /dev/null
+++ b/drivers/clk/uniphier/clk-uniphier-cpugear.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Socionext Inc.
+ * Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+
+#include "clk-uniphier.h"
+
+#define UNIPHIER_CLK_CPUGEAR_STAT 0 /* status */
+#define UNIPHIER_CLK_CPUGEAR_SET 4 /* set */
+#define UNIPHIER_CLK_CPUGEAR_UPD 8 /* update */
+#define UNIPHIER_CLK_CPUGEAR_UPD_BIT BIT(0)
+
+struct uniphier_clk_cpugear {
+ struct clk_hw hw;
+ struct regmap *regmap;
+ unsigned int regbase;
+ unsigned int mask;
+};
+
+#define to_uniphier_clk_cpugear(_hw) \
+ container_of(_hw, struct uniphier_clk_cpugear, hw)
+
+static int uniphier_clk_cpugear_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct uniphier_clk_cpugear *gear = to_uniphier_clk_cpugear(hw);
+ int ret;
+ unsigned int val;
+
+ ret = regmap_write_bits(gear->regmap,
+ gear->regbase + UNIPHIER_CLK_CPUGEAR_SET,
+ gear->mask, index);
+ if (ret)
+ return ret;
+
+ ret = regmap_write_bits(gear->regmap,
+ gear->regbase + UNIPHIER_CLK_CPUGEAR_UPD,
+ UNIPHIER_CLK_CPUGEAR_UPD_BIT,
+ UNIPHIER_CLK_CPUGEAR_UPD_BIT);
+ if (ret)
+ return ret;
+
+ return regmap_read_poll_timeout(gear->regmap,
+ gear->regbase + UNIPHIER_CLK_CPUGEAR_UPD,
+ val, !(val & UNIPHIER_CLK_CPUGEAR_UPD_BIT),
+ 0, 1);
+}
+
+static u8 uniphier_clk_cpugear_get_parent(struct clk_hw *hw)
+{
+ struct uniphier_clk_cpugear *gear = to_uniphier_clk_cpugear(hw);
+ int num_parents = clk_hw_get_num_parents(hw);
+ int ret;
+ unsigned int val;
+
+ ret = regmap_read(gear->regmap,
+ gear->regbase + UNIPHIER_CLK_CPUGEAR_STAT, &val);
+ if (ret)
+ return ret;
+
+ val &= gear->mask;
+
+ return val < num_parents ? val : -EINVAL;
+}
+
+static const struct clk_ops uniphier_clk_cpugear_ops = {
+ .determine_rate = __clk_mux_determine_rate,
+ .set_parent = uniphier_clk_cpugear_set_parent,
+ .get_parent = uniphier_clk_cpugear_get_parent,
+};
+
+struct clk_hw *uniphier_clk_register_cpugear(struct device *dev,
+ struct regmap *regmap,
+ const char *name,
+ const struct uniphier_clk_cpugear_data *data)
+{
+ struct uniphier_clk_cpugear *gear;
+ struct clk_init_data init;
+ int ret;
+
+ gear = devm_kzalloc(dev, sizeof(*gear), GFP_KERNEL);
+ if (!gear)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &uniphier_clk_cpugear_ops;
+ init.flags = CLK_SET_RATE_PARENT;
+ init.parent_names = data->parent_names;
+ init.num_parents = data->num_parents;
+
+ gear->regmap = regmap;
+ gear->regbase = data->regbase;
+ gear->mask = data->mask;
+ gear->hw.init = &init;
+
+ ret = devm_clk_hw_register(dev, &gear->hw);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return &gear->hw;
+}