1 files changed, 241 insertions, 0 deletions
diff --git a/drivers/clk/clk-fixed-rate.c b/drivers/clk/clk-fixed-rate.c
new file mode 100644
index 000000000..6d6475c32
--- /dev/null
+++ b/drivers/clk/clk-fixed-rate.c
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Fixed rate clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/*
+ * DOC: basic fixed-rate clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parents are prepared
+ * enable - clk_enable only ensures parents are enabled
+ * rate - rate is always a fixed value.  No clk_set_rate support
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+static unsigned long clk_fixed_rate_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	return to_clk_fixed_rate(hw)->fixed_rate;
+}
+
+static unsigned long clk_fixed_rate_recalc_accuracy(struct clk_hw *hw,
+		unsigned long parent_accuracy)
+{
+	return to_clk_fixed_rate(hw)->fixed_accuracy;
+}
+
+const struct clk_ops clk_fixed_rate_ops = {
+	.recalc_rate = clk_fixed_rate_recalc_rate,
+	.recalc_accuracy = clk_fixed_rate_recalc_accuracy,
+};
+EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
+
+/**
+ * clk_hw_register_fixed_rate_with_accuracy - register fixed-rate clock with
+ * the clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @flags: framework-specific flags
+ * @fixed_rate: non-adjustable clock rate
+ * @fixed_accuracy: non-adjustable clock rate
+ */
+struct clk_hw *clk_hw_register_fixed_rate_with_accuracy(struct device *dev,
+		const char *name, const char *parent_name, unsigned long flags,
+		unsigned long fixed_rate, unsigned long fixed_accuracy)
+{
+	struct clk_fixed_rate *fixed;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	/* allocate fixed-rate clock */
+	fixed = kzalloc(sizeof(*fixed), GFP_KERNEL);
+	if (!fixed)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &clk_fixed_rate_ops;
+	init.flags = flags | CLK_IS_BASIC;
+	init.parent_names = (parent_name ? &parent_name: NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+
+	/* struct clk_fixed_rate assignments */
+	fixed->fixed_rate = fixed_rate;
+	fixed->fixed_accuracy = fixed_accuracy;
+	fixed->hw.init = &init;
+
+	/* register the clock */
+	hw = &fixed->hw;
+	ret = clk_hw_register(dev, hw);
+	if (ret) {
+		kfree(fixed);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_fixed_rate_with_accuracy);
+
+struct clk *clk_register_fixed_rate_with_accuracy(struct device *dev,
+		const char *name, const char *parent_name, unsigned long flags,
+		unsigned long fixed_rate, unsigned long fixed_accuracy)
+{
+	struct clk_hw *hw;
+
+	hw = clk_hw_register_fixed_rate_with_accuracy(dev, name, parent_name,
+			flags, fixed_rate, fixed_accuracy);
+	if (IS_ERR(hw))
+		return ERR_CAST(hw);
+	return hw->clk;
+}
+EXPORT_SYMBOL_GPL(clk_register_fixed_rate_with_accuracy);
+
+/**
+ * clk_hw_register_fixed_rate - register fixed-rate clock with the clock
+ * framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @flags: framework-specific flags
+ * @fixed_rate: non-adjustable clock rate
+ */
+struct clk_hw *clk_hw_register_fixed_rate(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		unsigned long fixed_rate)
+{
+	return clk_hw_register_fixed_rate_with_accuracy(dev, name, parent_name,
+						     flags, fixed_rate, 0);
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_fixed_rate);
+
+struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		unsigned long fixed_rate)
+{
+	return clk_register_fixed_rate_with_accuracy(dev, name, parent_name,
+						     flags, fixed_rate, 0);
+}
+EXPORT_SYMBOL_GPL(clk_register_fixed_rate);
+
+void clk_unregister_fixed_rate(struct clk *clk)
+{
+	struct clk_hw *hw;
+
+	hw = __clk_get_hw(clk);
+	if (!hw)
+		return;
+
+	clk_unregister(clk);
+	kfree(to_clk_fixed_rate(hw));
+}
+EXPORT_SYMBOL_GPL(clk_unregister_fixed_rate);
+
+void clk_hw_unregister_fixed_rate(struct clk_hw *hw)
+{
+	struct clk_fixed_rate *fixed;
+
+	fixed = to_clk_fixed_rate(hw);
+
+	clk_hw_unregister(hw);
+	kfree(fixed);
+}
+EXPORT_SYMBOL_GPL(clk_hw_unregister_fixed_rate);
+
+#ifdef CONFIG_OF
+static struct clk *_of_fixed_clk_setup(struct device_node *node)
+{
+	struct clk *clk;
+	const char *clk_name = node->name;
+	u32 rate;
+	u32 accuracy = 0;
+	int ret;
+
+	if (of_property_read_u32(node, "clock-frequency", &rate))
+		return ERR_PTR(-EIO);
+
+	of_property_read_u32(node, "clock-accuracy", &accuracy);
+
+	of_property_read_string(node, "clock-output-names", &clk_name);
+
+	clk = clk_register_fixed_rate_with_accuracy(NULL, clk_name, NULL,
+						    0, rate, accuracy);
+	if (IS_ERR(clk))
+		return clk;
+
+	ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+	if (ret) {
+		clk_unregister(clk);
+		return ERR_PTR(ret);
+	}
+
+	return clk;
+}
+
+/**
+ * of_fixed_clk_setup() - Setup function for simple fixed rate clock
+ */
+void __init of_fixed_clk_setup(struct device_node *node)
+{
+	_of_fixed_clk_setup(node);
+}
+CLK_OF_DECLARE(fixed_clk, "fixed-clock", of_fixed_clk_setup);
+
+static int of_fixed_clk_remove(struct platform_device *pdev)
+{
+	struct clk *clk = platform_get_drvdata(pdev);
+
+	of_clk_del_provider(pdev->dev.of_node);
+	clk_unregister_fixed_rate(clk);
+
+	return 0;
+}
+
+static int of_fixed_clk_probe(struct platform_device *pdev)
+{
+	struct clk *clk;
+
+	/*
+	 * This function is not executed when of_fixed_clk_setup
+	 * succeeded.
+	 */
+	clk = _of_fixed_clk_setup(pdev->dev.of_node);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	platform_set_drvdata(pdev, clk);
+
+	return 0;
+}
+
+static const struct of_device_id of_fixed_clk_ids[] = {
+	{ .compatible = "fixed-clock" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, of_fixed_clk_ids);
+
+static struct platform_driver of_fixed_clk_driver = {
+	.driver = {
+		.name = "of_fixed_clk",
+		.of_match_table = of_fixed_clk_ids,
+	},
+	.probe = of_fixed_clk_probe,
+	.remove = of_fixed_clk_remove,
+};
+builtin_platform_driver(of_fixed_clk_driver);
+#endif