1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
new file mode 100644
index 000000000..e54e79714
--- /dev/null
+++ b/drivers/clk/clk-mux.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * Simple multiplexer clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+/*
+ * DOC: basic adjustable multiplexer clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is only affected by parent switching.  No clk_set_rate support
+ * parent - parent is adjustable through clk_set_parent
+ */
+
+static inline u32 clk_mux_readl(struct clk_mux *mux)
+{
+	if (mux->flags & CLK_MUX_BIG_ENDIAN)
+		return ioread32be(mux->reg);
+
+	return readl(mux->reg);
+}
+
+static inline void clk_mux_writel(struct clk_mux *mux, u32 val)
+{
+	if (mux->flags & CLK_MUX_BIG_ENDIAN)
+		iowrite32be(val, mux->reg);
+	else
+		writel(val, mux->reg);
+}
+
+int clk_mux_val_to_index(struct clk_hw *hw, u32 *table, unsigned int flags,
+			 unsigned int val)
+{
+	int num_parents = clk_hw_get_num_parents(hw);
+
+	if (table) {
+		int i;
+
+		for (i = 0; i < num_parents; i++)
+			if (table[i] == val)
+				return i;
+		return -EINVAL;
+	}
+
+	if (val && (flags & CLK_MUX_INDEX_BIT))
+		val = ffs(val) - 1;
+
+	if (val && (flags & CLK_MUX_INDEX_ONE))
+		val--;
+
+	if (val >= num_parents)
+		return -EINVAL;
+
+	return val;
+}
+EXPORT_SYMBOL_GPL(clk_mux_val_to_index);
+
+unsigned int clk_mux_index_to_val(u32 *table, unsigned int flags, u8 index)
+{
+	unsigned int val = index;
+
+	if (table) {
+		val = table[index];
+	} else {
+		if (flags & CLK_MUX_INDEX_BIT)
+			val = 1 << index;
+
+		if (flags & CLK_MUX_INDEX_ONE)
+			val++;
+	}
+
+	return val;
+}
+EXPORT_SYMBOL_GPL(clk_mux_index_to_val);
+
+static u8 clk_mux_get_parent(struct clk_hw *hw)
+{
+	struct clk_mux *mux = to_clk_mux(hw);
+	u32 val;
+
+	val = clk_mux_readl(mux) >> mux->shift;
+	val &= mux->mask;
+
+	return clk_mux_val_to_index(hw, mux->table, mux->flags, val);
+}
+
+static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_mux *mux = to_clk_mux(hw);
+	u32 val = clk_mux_index_to_val(mux->table, mux->flags, index);
+	unsigned long flags = 0;
+	u32 reg;
+
+	if (mux->lock)
+		spin_lock_irqsave(mux->lock, flags);
+	else
+		__acquire(mux->lock);
+
+	if (mux->flags & CLK_MUX_HIWORD_MASK) {
+		reg = mux->mask << (mux->shift + 16);
+	} else {
+		reg = clk_mux_readl(mux);
+		reg &= ~(mux->mask << mux->shift);
+	}
+	val = val << mux->shift;
+	reg |= val;
+	clk_mux_writel(mux, reg);
+
+	if (mux->lock)
+		spin_unlock_irqrestore(mux->lock, flags);
+	else
+		__release(mux->lock);
+
+	return 0;
+}
+
+static int clk_mux_determine_rate(struct clk_hw *hw,
+				  struct clk_rate_request *req)
+{
+	struct clk_mux *mux = to_clk_mux(hw);
+
+	return clk_mux_determine_rate_flags(hw, req, mux->flags);
+}
+
+const struct clk_ops clk_mux_ops = {
+	.get_parent = clk_mux_get_parent,
+	.set_parent = clk_mux_set_parent,
+	.determine_rate = clk_mux_determine_rate,
+};
+EXPORT_SYMBOL_GPL(clk_mux_ops);
+
+const struct clk_ops clk_mux_ro_ops = {
+	.get_parent = clk_mux_get_parent,
+};
+EXPORT_SYMBOL_GPL(clk_mux_ro_ops);
+
+struct clk_hw *__clk_hw_register_mux(struct device *dev, struct device_node *np,
+		const char *name, u8 num_parents,
+		const char * const *parent_names,
+		const struct clk_hw **parent_hws,
+		const struct clk_parent_data *parent_data,
+		unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
+{
+	struct clk_mux *mux;
+	struct clk_hw *hw;
+	struct clk_init_data init = {};
+	u8 width = 0;
+	int ret = -EINVAL;
+
+	if (clk_mux_flags & CLK_MUX_HIWORD_MASK) {
+		width = fls(mask) - ffs(mask) + 1;
+		if (width + shift > 16) {
+			pr_err("mux value exceeds LOWORD field\n");
+			return ERR_PTR(-EINVAL);
+		}
+	}
+
+	/* allocate the mux */
+	mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	if (clk_mux_flags & CLK_MUX_READ_ONLY)
+		init.ops = &clk_mux_ro_ops;
+	else
+		init.ops = &clk_mux_ops;
+	init.flags = flags;
+	init.parent_names = parent_names;
+	init.parent_data = parent_data;
+	init.parent_hws = parent_hws;
+	init.num_parents = num_parents;
+
+	/* struct clk_mux assignments */
+	mux->reg = reg;
+	mux->shift = shift;
+	mux->mask = mask;
+	mux->flags = clk_mux_flags;
+	mux->lock = lock;
+	mux->table = table;
+	mux->hw.init = &init;
+
+	hw = &mux->hw;
+	if (dev || !np)
+		ret = clk_hw_register(dev, hw);
+	else if (np)
+		ret = of_clk_hw_register(np, hw);
+	if (ret) {
+		kfree(mux);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+EXPORT_SYMBOL_GPL(__clk_hw_register_mux);
+
+struct clk *clk_register_mux_table(struct device *dev, const char *name,
+		const char * const *parent_names, u8 num_parents,
+		unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
+{
+	struct clk_hw *hw;
+
+	hw = clk_hw_register_mux_table(dev, name, parent_names,
+				       num_parents, flags, reg, shift, mask,
+				       clk_mux_flags, table, lock);
+	if (IS_ERR(hw))
+		return ERR_CAST(hw);
+	return hw->clk;
+}
+EXPORT_SYMBOL_GPL(clk_register_mux_table);
+
+void clk_unregister_mux(struct clk *clk)
+{
+	struct clk_mux *mux;
+	struct clk_hw *hw;
+
+	hw = __clk_get_hw(clk);
+	if (!hw)
+		return;
+
+	mux = to_clk_mux(hw);
+
+	clk_unregister(clk);
+	kfree(mux);
+}
+EXPORT_SYMBOL_GPL(clk_unregister_mux);
+
+void clk_hw_unregister_mux(struct clk_hw *hw)
+{
+	struct clk_mux *mux;
+
+	mux = to_clk_mux(hw);
+
+	clk_hw_unregister(hw);
+	kfree(mux);
+}
+EXPORT_SYMBOL_GPL(clk_hw_unregister_mux);