diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 9b3cd08..2eaf17e 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -8,3 +8,43 @@ config HAVE_CLK_PREPARE
 
 config HAVE_MACH_CLKDEV
 	bool
+
+menuconfig COMMON_CLK
+	bool "Common Clock Framework"
+	select HAVE_CLK_PREPARE
+	---help---
+	  The common clock framework is a single definition of struct
+	  clk, useful across many platforms, as well as an
+	  implementation of the clock API in include/linux/clk.h.
+	  Architectures utilizing the common struct clk should select
+	  this automatically, but it may be necessary to manually select
+	  this option for loadable modules requiring the common clock
+	  framework.
+
+	  If in doubt, say "N".
+
+if COMMON_CLK
+
+config COMMON_CLK_DISABLE_UNUSED
+	bool "Disabled unused clocks at boot"
+	depends on COMMON_CLK
+	---help---
+	  Traverses the entire clock tree and disables any clocks that are
+	  enabled in hardware but have not been enabled by any device drivers.
+	  This saves power and keeps the software model of the clock in line
+	  with reality.
+
+	  If in doubt, say "N".
+
+config COMMON_CLK_DEBUG
+	bool "DebugFS representation of clock tree"
+	depends on COMMON_CLK
+	select DEBUG_FS
+	---help---
+	  Creates a directory hierchy in debugfs for visualizing the clk
+	  tree structure.  Each directory contains read-only members
+	  that export information specific to that clk node: clk_rate,
+	  clk_flags, clk_prepare_count, clk_enable_count &
+	  clk_notifier_count.
+
+endif
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 07613fa..ff362c4 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -1,2 +1,3 @@
 
 obj-$(CONFIG_CLKDEV_LOOKUP)	+= clkdev.o
+obj-$(CONFIG_COMMON_CLK)	+= clk.o
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
new file mode 100644
index 0000000..9cf6f59
--- /dev/null
+++ b/drivers/clk/clk.c
@@ -0,0 +1,1461 @@
+/*
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 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.
+ *
+ * Standard functionality for the common clock API.  See Documentation/clk.txt
+ */
+
+#include <linux/clk-private.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/err.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+static DEFINE_SPINLOCK(enable_lock);
+static DEFINE_MUTEX(prepare_lock);
+
+static HLIST_HEAD(clk_root_list);
+static HLIST_HEAD(clk_orphan_list);
+static LIST_HEAD(clk_notifier_list);
+
+/***        debugfs support        ***/
+
+#ifdef CONFIG_COMMON_CLK_DEBUG
+#include <linux/debugfs.h>
+
+static struct dentry *rootdir;
+static struct dentry *orphandir;
+static int inited = 0;
+
+/* caller must hold prepare_lock */
+static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry)
+{
+	struct dentry *d;
+	int ret = -ENOMEM;
+
+	if (!clk || !pdentry) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	d = debugfs_create_dir(clk->name, pdentry);
+	if (!d)
+		goto out;
+
+	clk->dentry = d;
+
+	d = debugfs_create_u32("clk_rate", S_IRUGO, clk->dentry,
+			(u32 *)&clk->rate);
+	if (!d)
+		goto err_out;
+
+	d = debugfs_create_x32("clk_flags", S_IRUGO, clk->dentry,
+			(u32 *)&clk->flags);
+	if (!d)
+		goto err_out;
+
+	d = debugfs_create_u32("clk_prepare_count", S_IRUGO, clk->dentry,
+			(u32 *)&clk->prepare_count);
+	if (!d)
+		goto err_out;
+
+	d = debugfs_create_u32("clk_enable_count", S_IRUGO, clk->dentry,
+			(u32 *)&clk->enable_count);
+	if (!d)
+		goto err_out;
+
+	d = debugfs_create_u32("clk_notifier_count", S_IRUGO, clk->dentry,
+			(u32 *)&clk->notifier_count);
+	if (!d)
+		goto err_out;
+
+	ret = 0;
+	goto out;
+
+err_out:
+	debugfs_remove(clk->dentry);
+out:
+	return ret;
+}
+
+/* caller must hold prepare_lock */
+static int clk_debug_create_subtree(struct clk *clk, struct dentry *pdentry)
+{
+	struct clk *child;
+	struct hlist_node *tmp;
+	int ret = -EINVAL;;
+
+	if (!clk || !pdentry)
+		goto out;
+
+	ret = clk_debug_create_one(clk, pdentry);
+
+	if (ret)
+		goto out;
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node)
+		clk_debug_create_subtree(child, clk->dentry);
+
+	ret = 0;
+out:
+	return ret;
+}
+
+/**
+ * clk_debug_register - add a clk node to the debugfs clk tree
+ * @clk: the clk being added to the debugfs clk tree
+ *
+ * Dynamically adds a clk to the debugfs clk tree if debugfs has been
+ * initialized.  Otherwise it bails out early since the debugfs clk tree
+ * will be created lazily by clk_debug_init as part of a late_initcall.
+ *
+ * Caller must hold prepare_lock.  Only clk_init calls this function (so
+ * far) so this is taken care.
+ */
+static int clk_debug_register(struct clk *clk)
+{
+	struct clk *parent;
+	struct dentry *pdentry;
+	int ret = 0;
+
+	if (!inited)
+		goto out;
+
+	parent = clk->parent;
+
+	/*
+	 * Check to see if a clk is a root clk.  Also check that it is
+	 * safe to add this clk to debugfs
+	 */
+	if (!parent)
+		if (clk->flags & CLK_IS_ROOT)
+			pdentry = rootdir;
+		else
+			pdentry = orphandir;
+	else
+		if (parent->dentry)
+			pdentry = parent->dentry;
+		else
+			goto out;
+
+	ret = clk_debug_create_subtree(clk, pdentry);
+
+out:
+	return ret;
+}
+
+/**
+ * clk_debug_init - lazily create the debugfs clk tree visualization
+ *
+ * clks are often initialized very early during boot before memory can
+ * be dynamically allocated and well before debugfs is setup.
+ * clk_debug_init walks the clk tree hierarchy while holding
+ * prepare_lock and creates the topology as part of a late_initcall,
+ * thus insuring that clks initialized very early will still be
+ * represented in the debugfs clk tree.  This function should only be
+ * called once at boot-time, and all other clks added dynamically will
+ * be done so with clk_debug_register.
+ */
+static int __init clk_debug_init(void)
+{
+	struct clk *clk;
+	struct hlist_node *tmp;
+
+	rootdir = debugfs_create_dir("clk", NULL);
+
+	if (!rootdir)
+		return -ENOMEM;
+
+	orphandir = debugfs_create_dir("orphans", rootdir);
+
+	if (!orphandir)
+		return -ENOMEM;
+
+	mutex_lock(&prepare_lock);
+
+	hlist_for_each_entry(clk, tmp, &clk_root_list, child_node)
+		clk_debug_create_subtree(clk, rootdir);
+
+	hlist_for_each_entry(clk, tmp, &clk_orphan_list, child_node)
+		clk_debug_create_subtree(clk, orphandir);
+
+	inited = 1;
+
+	mutex_unlock(&prepare_lock);
+
+	return 0;
+}
+late_initcall(clk_debug_init);
+#else
+static inline int clk_debug_register(struct clk *clk) { return 0; }
+#endif /* CONFIG_COMMON_CLK_DEBUG */
+
+#ifdef CONFIG_COMMON_CLK_DISABLE_UNUSED
+/* caller must hold prepare_lock */
+static void clk_disable_unused_subtree(struct clk *clk)
+{
+	struct clk *child;
+	struct hlist_node *tmp;
+	unsigned long flags;
+
+	if (!clk)
+		goto out;
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node)
+		clk_disable_unused_subtree(child);
+
+	spin_lock_irqsave(&enable_lock, flags);
+
+	if (clk->enable_count)
+		goto unlock_out;
+
+	if (clk->flags & CLK_IGNORE_UNUSED)
+		goto unlock_out;
+
+	if (__clk_is_enabled(clk) && clk->ops->disable)
+		clk->ops->disable(clk->hw);
+
+unlock_out:
+	spin_unlock_irqrestore(&enable_lock, flags);
+
+out:
+	return;
+}
+
+static int clk_disable_unused(void)
+{
+	struct clk *clk;
+	struct hlist_node *tmp;
+
+	mutex_lock(&prepare_lock);
+
+	hlist_for_each_entry(clk, tmp, &clk_root_list, child_node)
+		clk_disable_unused_subtree(clk);
+
+	hlist_for_each_entry(clk, tmp, &clk_orphan_list, child_node)
+		clk_disable_unused_subtree(clk);
+
+	mutex_unlock(&prepare_lock);
+
+	return 0;
+}
+late_initcall(clk_disable_unused);
+#else
+static inline int clk_disable_unused(struct clk *clk) { return 0; }
+#endif /* CONFIG_COMMON_CLK_DISABLE_UNUSED */
+
+/***    helper functions   ***/
+
+inline const char *__clk_get_name(struct clk *clk)
+{
+	return !clk ? NULL : clk->name;
+}
+
+inline struct clk_hw *__clk_get_hw(struct clk *clk)
+{
+	return !clk ? NULL : clk->hw;
+}
+
+inline u8 __clk_get_num_parents(struct clk *clk)
+{
+	return !clk ? -EINVAL : clk->num_parents;
+}
+
+inline struct clk *__clk_get_parent(struct clk *clk)
+{
+	return !clk ? NULL : clk->parent;
+}
+
+inline int __clk_get_enable_count(struct clk *clk)
+{
+	return !clk ? -EINVAL : clk->enable_count;
+}
+
+inline int __clk_get_prepare_count(struct clk *clk)
+{
+	return !clk ? -EINVAL : clk->prepare_count;
+}
+
+unsigned long __clk_get_rate(struct clk *clk)
+{
+	unsigned long ret;
+
+	if (!clk) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = clk->rate;
+
+	if (clk->flags & CLK_IS_ROOT)
+		goto out;
+
+	if (!clk->parent)
+		ret = -ENODEV;
+
+out:
+	return ret;
+}
+
+inline unsigned long __clk_get_flags(struct clk *clk)
+{
+	return !clk ? -EINVAL : clk->flags;
+}
+
+int __clk_is_enabled(struct clk *clk)
+{
+	int ret;
+
+	if (!clk)
+		return -EINVAL;
+
+	/*
+	 * .is_enabled is only mandatory for clocks that gate
+	 * fall back to software usage counter if .is_enabled is missing
+	 */
+	if (!clk->ops->is_enabled) {
+		ret = clk->enable_count ? 1 : 0;
+		goto out;
+	}
+
+	ret = clk->ops->is_enabled(clk->hw);
+out:
+	return ret;
+}
+
+static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk)
+{
+	struct clk *child;
+	struct clk *ret;
+	struct hlist_node *tmp;
+
+	if (!strcmp(clk->name, name))
+		return clk;
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+		ret = __clk_lookup_subtree(name, child);
+		if (ret)
+			return ret;
+	}
+
+	return NULL;
+}
+
+struct clk *__clk_lookup(const char *name)
+{
+	struct clk *root_clk;
+	struct clk *ret;
+	struct hlist_node *tmp;
+
+	if (!name)
+		return NULL;
+
+	/* search the 'proper' clk tree first */
+	hlist_for_each_entry(root_clk, tmp, &clk_root_list, child_node) {
+		ret = __clk_lookup_subtree(name, root_clk);
+		if (ret)
+			return ret;
+	}
+
+	/* if not found, then search the orphan tree */
+	hlist_for_each_entry(root_clk, tmp, &clk_orphan_list, child_node) {
+		ret = __clk_lookup_subtree(name, root_clk);
+		if (ret)
+			return ret;
+	}
+
+	return NULL;
+}
+
+/***        clk api        ***/
+
+void __clk_unprepare(struct clk *clk)
+{
+	if (!clk)
+		return;
+
+	if (WARN_ON(clk->prepare_count == 0))
+		return;
+
+	if (--clk->prepare_count > 0)
+		return;
+
+	WARN_ON(clk->enable_count > 0);
+
+	if (clk->ops->unprepare)
+		clk->ops->unprepare(clk->hw);
+
+	__clk_unprepare(clk->parent);
+}
+
+/**
+ * clk_unprepare - undo preparation of a clock source
+ * @clk: the clk being unprepare
+ *
+ * clk_unprepare may sleep, which differentiates it from clk_disable.  In a
+ * simple case, clk_unprepare can be used instead of clk_disable to gate a clk
+ * if the operation may sleep.  One example is a clk which is accessed over
+ * I2c.  In the complex case a clk gate operation may require a fast and a slow
+ * part.  It is this reason that clk_unprepare and clk_disable are not mutually
+ * exclusive.  In fact clk_disable must be called before clk_unprepare.
+ */
+void clk_unprepare(struct clk *clk)
+{
+	mutex_lock(&prepare_lock);
+	__clk_unprepare(clk);
+	mutex_unlock(&prepare_lock);
+}
+EXPORT_SYMBOL_GPL(clk_unprepare);
+
+int __clk_prepare(struct clk *clk)
+{
+	int ret = 0;
+
+	if (!clk)
+		return 0;
+
+	if (clk->prepare_count == 0) {
+		ret = __clk_prepare(clk->parent);
+		if (ret)
+			return ret;
+
+		if (clk->ops->prepare) {
+			ret = clk->ops->prepare(clk->hw);
+			if (ret) {
+				__clk_unprepare(clk->parent);
+				return ret;
+			}
+		}
+	}
+
+	clk->prepare_count++;
+
+	return 0;
+}
+
+/**
+ * clk_prepare - prepare a clock source
+ * @clk: the clk being prepared
+ *
+ * clk_prepare may sleep, which differentiates it from clk_enable.  In a simple
+ * case, clk_prepare can be used instead of clk_enable to ungate a clk if the
+ * operation may sleep.  One example is a clk which is accessed over I2c.  In
+ * the complex case a clk ungate operation may require a fast and a slow part.
+ * It is this reason that clk_prepare and clk_enable are not mutually
+ * exclusive.  In fact clk_prepare must be called before clk_enable.
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int clk_prepare(struct clk *clk)
+{
+	int ret;
+
+	mutex_lock(&prepare_lock);
+	ret = __clk_prepare(clk);
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_prepare);
+
+static void __clk_disable(struct clk *clk)
+{
+	if (!clk)
+		return;
+
+	if (WARN_ON(clk->enable_count == 0))
+		return;
+
+	if (--clk->enable_count > 0)
+		return;
+
+	if (clk->ops->disable)
+		clk->ops->disable(clk->hw);
+
+	__clk_disable(clk->parent);
+}
+
+/**
+ * clk_disable - gate a clock
+ * @clk: the clk being gated
+ *
+ * clk_disable must not sleep, which differentiates it from clk_unprepare.  In
+ * a simple case, clk_disable can be used instead of clk_unprepare to gate a
+ * clk if the operation is fast and will never sleep.  One example is a
+ * SoC-internal clk which is controlled via simple register writes.  In the
+ * complex case a clk gate operation may require a fast and a slow part.  It is
+ * this reason that clk_unprepare and clk_disable are not mutually exclusive.
+ * In fact clk_disable must be called before clk_unprepare.
+ */
+void clk_disable(struct clk *clk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&enable_lock, flags);
+	__clk_disable(clk);
+	spin_unlock_irqrestore(&enable_lock, flags);
+}
+EXPORT_SYMBOL_GPL(clk_disable);
+
+static int __clk_enable(struct clk *clk)
+{
+	int ret = 0;
+
+	if (!clk)
+		return 0;
+
+	if (WARN_ON(clk->prepare_count == 0))
+		return -ESHUTDOWN;
+
+	if (clk->enable_count == 0) {
+		ret = __clk_enable(clk->parent);
+
+		if (ret)
+			return ret;
+
+		if (clk->ops->enable) {
+			ret = clk->ops->enable(clk->hw);
+			if (ret) {
+				__clk_disable(clk->parent);
+				return ret;
+			}
+		}
+	}
+
+	clk->enable_count++;
+	return 0;
+}
+
+/**
+ * clk_enable - ungate a clock
+ * @clk: the clk being ungated
+ *
+ * clk_enable must not sleep, which differentiates it from clk_prepare.  In a
+ * simple case, clk_enable can be used instead of clk_prepare to ungate a clk
+ * if the operation will never sleep.  One example is a SoC-internal clk which
+ * is controlled via simple register writes.  In the complex case a clk ungate
+ * operation may require a fast and a slow part.  It is this reason that
+ * clk_enable and clk_prepare are not mutually exclusive.  In fact clk_prepare
+ * must be called before clk_enable.  Returns 0 on success, -EERROR
+ * otherwise.
+ */
+int clk_enable(struct clk *clk)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&enable_lock, flags);
+	ret = __clk_enable(clk);
+	spin_unlock_irqrestore(&enable_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_enable);
+
+/**
+ * clk_get_rate - return the rate of clk
+ * @clk: the clk whose rate is being returned
+ *
+ * Simply returns the cached rate of the clk.  Does not query the hardware.  If
+ * clk is NULL then returns -EINVAL.
+ */
+unsigned long clk_get_rate(struct clk *clk)
+{
+	unsigned long rate;
+
+	mutex_lock(&prepare_lock);
+	rate = __clk_get_rate(clk);
+	mutex_unlock(&prepare_lock);
+
+	return rate;
+}
+EXPORT_SYMBOL_GPL(clk_get_rate);
+
+/**
+ * __clk_round_rate - round the given rate for a clk
+ * @clk: round the rate of this clock
+ *
+ * Caller must hold prepare_lock.  Useful for clk_ops such as .set_rate
+ */
+unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long unused;
+
+	if (!clk)
+		return -EINVAL;
+
+	if (!clk->ops->round_rate)
+		return clk->rate;
+
+	if (clk->flags & CLK_SET_RATE_PARENT)
+		return clk->ops->round_rate(clk->hw, rate, &unused);
+	else
+		return clk->ops->round_rate(clk->hw, rate, NULL);
+}
+
+/**
+ * clk_round_rate - round the given rate for a clk
+ * @clk: the clk for which we are rounding a rate
+ * @rate: the rate which is to be rounded
+ *
+ * Takes in a rate as input and rounds it to a rate that the clk can actually
+ * use which is then returned.  If clk doesn't support round_rate operation
+ * then the parent rate is returned.
+ */
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long ret;
+
+	mutex_lock(&prepare_lock);
+	ret = __clk_round_rate(clk, rate);
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_round_rate);
+
+/**
+ * __clk_notify - call clk notifier chain
+ * @clk: struct clk * that is changing rate
+ * @msg: clk notifier type (see include/linux/clk.h)
+ * @old_rate: old clk rate
+ * @new_rate: new clk rate
+ *
+ * Triggers a notifier call chain on the clk rate-change notification
+ * for 'clk'.  Passes a pointer to the struct clk and the previous
+ * and current rates to the notifier callback.  Intended to be called by
+ * internal clock code only.  Returns NOTIFY_DONE from the last driver
+ * called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if
+ * a driver returns that.
+ */
+static int __clk_notify(struct clk *clk, unsigned long msg,
+		unsigned long old_rate, unsigned long new_rate)
+{
+	struct clk_notifier *cn;
+	struct clk_notifier_data cnd;
+	int ret = NOTIFY_DONE;
+
+	cnd.clk = clk;
+	cnd.old_rate = old_rate;
+	cnd.new_rate = new_rate;
+
+	list_for_each_entry(cn, &clk_notifier_list, node) {
+		if (cn->clk == clk) {
+			ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
+					&cnd);
+			break;
+		}
+	}
+
+	return ret;
+}
+
+/**
+ * __clk_recalc_rates
+ * @clk: first clk in the subtree
+ * @msg: notification type (see include/linux/clk.h)
+ *
+ * Walks the subtree of clks starting with clk and recalculates rates as it
+ * goes.  Note that if a clk does not implement the .recalc_rate callback then
+ * it is assumed that the clock will take on the rate of it's parent.
+ *
+ * clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
+ * if necessary.
+ *
+ * Caller must hold prepare_lock.
+ */
+static void __clk_recalc_rates(struct clk *clk, unsigned long msg)
+{
+	unsigned long old_rate;
+	unsigned long parent_rate = 0;
+	struct hlist_node *tmp;
+	struct clk *child;
+
+	old_rate = clk->rate;
+
+	if (clk->parent)
+		parent_rate = clk->parent->rate;
+
+	if (clk->ops->recalc_rate)
+		clk->rate = clk->ops->recalc_rate(clk->hw, parent_rate);
+	else
+		clk->rate = parent_rate;
+
+	/*
+	 * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
+	 * & ABORT_RATE_CHANGE notifiers
+	 */
+	if (clk->notifier_count && msg)
+		__clk_notify(clk, msg, old_rate, clk->rate);
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node)
+		__clk_recalc_rates(child, msg);
+}
+
+/**
+ * __clk_speculate_rates
+ * @clk: first clk in the subtree
+ * @parent_rate: the "future" rate of clk's parent
+ *
+ * Walks the subtree of clks starting with clk, speculating rates as it
+ * goes and firing off PRE_RATE_CHANGE notifications as necessary.
+ *
+ * Unlike clk_recalc_rates, clk_speculate_rates exists only for sending
+ * pre-rate change notifications and returns early if no clks in the
+ * subtree have subscribed to the notifications.  Note that if a clk does not
+ * implement the .recalc_rate callback then it is assumed that the clock will
+ * take on the rate of it's parent.
+ *
+ * Caller must hold prepare_lock.
+ */
+static int __clk_speculate_rates(struct clk *clk, unsigned long parent_rate)
+{
+	struct hlist_node *tmp;
+	struct clk *child;
+	unsigned long new_rate;
+	int ret = NOTIFY_DONE;
+
+	if (clk->ops->recalc_rate)
+		new_rate = clk->ops->recalc_rate(clk->hw, parent_rate);
+	else
+		new_rate = parent_rate;
+
+	/* abort the rate change if a driver returns NOTIFY_BAD */
+	if (clk->notifier_count)
+		ret = __clk_notify(clk, PRE_RATE_CHANGE, clk->rate, new_rate);
+
+	if (ret == NOTIFY_BAD)
+		goto out;
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+		ret = __clk_speculate_rates(child, new_rate);
+		if (ret == NOTIFY_BAD)
+			break;
+	}
+
+out:
+	return ret;
+}
+
+static void clk_calc_subtree(struct clk *clk, unsigned long new_rate)
+{
+	struct clk *child;
+	struct hlist_node *tmp;
+
+	clk->new_rate = new_rate;
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+		if (child->ops->recalc_rate)
+			child->new_rate = child->ops->recalc_rate(child->hw, new_rate);
+		else
+			child->new_rate = new_rate;
+		clk_calc_subtree(child, child->new_rate);
+	}
+}
+
+/*
+ * calculate the new rates returning the topmost clock that has to be
+ * changed.
+ */
+static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate)
+{
+	struct clk *top = clk;
+	unsigned long best_parent_rate = clk->parent->rate;
+	unsigned long new_rate;
+
+	if (!clk->ops->round_rate && !(clk->flags & CLK_SET_RATE_PARENT)) {
+		clk->new_rate = clk->rate;
+		return NULL;
+	}
+
+	if (!clk->ops->round_rate && (clk->flags & CLK_SET_RATE_PARENT)) {
+		top = clk_calc_new_rates(clk->parent, rate);
+		new_rate = clk->new_rate = clk->parent->new_rate;
+
+		goto out;
+	}
+
+	if (clk->flags & CLK_SET_RATE_PARENT)
+		new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate);
+	else
+		new_rate = clk->ops->round_rate(clk->hw, rate, NULL);
+
+	if (best_parent_rate != clk->parent->rate) {
+		top = clk_calc_new_rates(clk->parent, best_parent_rate);
+
+		goto out;
+	}
+
+out:
+	clk_calc_subtree(clk, new_rate);
+
+	return top;
+}
+
+/*
+ * Notify about rate changes in a subtree. Always walk down the whole tree
+ * so that in case of an error we can walk down the whole tree again and
+ * abort the change.
+ */
+static struct clk *clk_propagate_rate_change(struct clk *clk, unsigned long event)
+{
+	struct hlist_node *tmp;
+	struct clk *child, *fail_clk = NULL;
+	int ret = NOTIFY_DONE;
+
+	if (clk->rate == clk->new_rate)
+		return 0;
+
+	if (clk->notifier_count) {
+		ret = __clk_notify(clk, event, clk->rate, clk->new_rate);
+		if (ret == NOTIFY_BAD)
+			fail_clk = clk;
+	}
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+		clk = clk_propagate_rate_change(child, event);
+		if (clk)
+			fail_clk = clk;
+	}
+
+	return fail_clk;
+}
+
+/*
+ * walk down a subtree and set the new rates notifying the rate
+ * change on the way
+ */
+static void clk_change_rate(struct clk *clk)
+{
+	struct clk *child;
+	unsigned long old_rate;
+	struct hlist_node *tmp;
+
+	old_rate = clk->rate;
+
+	if (clk->ops->set_rate)
+		clk->ops->set_rate(clk->hw, clk->new_rate);
+
+	if (clk->ops->recalc_rate)
+		clk->rate = clk->ops->recalc_rate(clk->hw,
+				clk->parent->rate);
+	else
+		clk->rate = clk->parent->rate;
+
+	if (clk->notifier_count && old_rate != clk->rate)
+		__clk_notify(clk, POST_RATE_CHANGE, old_rate, clk->rate);
+
+	hlist_for_each_entry(child, tmp, &clk->children, child_node)
+		clk_change_rate(child);
+}
+
+/**
+ * clk_set_rate - specify a new rate for clk
+ * @clk: the clk whose rate is being changed
+ * @rate: the new rate for clk
+ *
+ * In the simplest case clk_set_rate will only change the rate of clk.
+ *
+ * If clk has the CLK_SET_RATE_GATE flag set and it is enabled this call
+ * will fail; only when the clk is disabled will it be able to change
+ * its rate.
+ *
+ * Setting the CLK_SET_RATE_PARENT flag allows clk_set_rate to
+ * recursively propagate up to clk's parent; whether or not this happens
+ * depends on the outcome of clk's .round_rate implementation.  If
+ * *parent_rate is 0 after calling .round_rate then upstream parent
+ * propagation is ignored.  If *parent_rate comes back with a new rate
+ * for clk's parent then we propagate up to clk's parent and set it's
+ * rate.  Upward propagation will continue until either a clk does not
+ * support the CLK_SET_RATE_PARENT flag or .round_rate stops requesting
+ * changes to clk's parent_rate.  If there is a failure during upstream
+ * propagation then clk_set_rate will unwind and restore each clk's rate
+ * that had been successfully changed.  Afterwards a rate change abort
+ * notification will be propagated downstream, starting from the clk
+ * that failed.
+ *
+ * At the end of all of the rate setting, clk_set_rate internally calls
+ * __clk_recalc_rates and propagates the rate changes downstream,
+ * starting from the highest clk whose rate was changed.  This has the
+ * added benefit of propagating post-rate change notifiers.
+ *
+ * Note that while post-rate change and rate change abort notifications
+ * are guaranteed to be sent to a clk only once per call to
+ * clk_set_rate, pre-change notifications will be sent for every clk
+ * whose rate is changed.  Stacking pre-change notifications is noisy
+ * for the drivers subscribed to them, but this allows drivers to react
+ * to intermediate clk rate changes up until the point where the final
+ * rate is achieved at the end of upstream propagation.
+ *
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+	struct clk *top, *fail_clk;
+	int ret = 0;
+
+	/* prevent racing with updates to the clock topology */
+	mutex_lock(&prepare_lock);
+
+	/* bail early if nothing to do */
+	if (rate == clk->rate)
+		goto out;
+
+	/* calculate new rates and get the topmost changed clock */
+	top = clk_calc_new_rates(clk, rate);
+	if (!top) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* notify that we are about to change rates */
+	fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
+	if (fail_clk) {
+		pr_warn("%s: failed to set %s rate\n", __func__,
+				fail_clk->name);
+		clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
+		ret = -EBUSY;
+		goto out;
+	}
+
+	/* change the rates */
+	clk_change_rate(top);
+
+	mutex_unlock(&prepare_lock);
+
+	return 0;
+out:
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate);
+
+/**
+ * clk_get_parent - return the parent of a clk
+ * @clk: the clk whose parent gets returned
+ *
+ * Simply returns clk->parent.  Returns NULL if clk is NULL.
+ */
+struct clk *clk_get_parent(struct clk *clk)
+{
+	struct clk *parent;
+
+	mutex_lock(&prepare_lock);
+	parent = __clk_get_parent(clk);
+	mutex_unlock(&prepare_lock);
+
+	return parent;
+}
+EXPORT_SYMBOL_GPL(clk_get_parent);
+
+/*
+ * .get_parent is mandatory for clocks with multiple possible parents.  It is
+ * optional for single-parent clocks.  Always call .get_parent if it is
+ * available and WARN if it is missing for multi-parent clocks.
+ *
+ * For single-parent clocks without .get_parent, first check to see if the
+ * .parents array exists, and if so use it to avoid an expensive tree
+ * traversal.  If .parents does not exist then walk the tree with __clk_lookup.
+ */
+static struct clk *__clk_init_parent(struct clk *clk)
+{
+	struct clk *ret = NULL;
+	u8 index;
+
+	/* handle the trivial cases */
+
+	if (!clk->num_parents)
+		goto out;
+
+	if (clk->num_parents == 1) {
+		if (IS_ERR_OR_NULL(clk->parent))
+			ret = clk->parent = __clk_lookup(clk->parent_names[0]);
+		ret = clk->parent;
+		goto out;
+	}
+
+	if (!clk->ops->get_parent) {
+		WARN(!clk->ops->get_parent,
+			"%s: multi-parent clocks must implement .get_parent\n",
+			__func__);
+		goto out;
+	};
+
+	/*
+	 * Do our best to cache parent clocks in clk->parents.  This prevents
+	 * unnecessary and expensive calls to __clk_lookup.  We don't set
+	 * clk->parent here; that is done by the calling function
+	 */
+
+	index = clk->ops->get_parent(clk->hw);
+
+	if (!clk->parents)
+		clk->parents =
+			kmalloc((sizeof(struct clk*) * clk->num_parents),
+					GFP_KERNEL);
+
+	if (!clk->parents)
+		ret = __clk_lookup(clk->parent_names[index]);
+	else if (!clk->parents[index])
+		ret = clk->parents[index] =
+			__clk_lookup(clk->parent_names[index]);
+	else
+		ret = clk->parents[index];
+
+out:
+	return ret;
+}
+
+void __clk_reparent(struct clk *clk, struct clk *new_parent)
+{
+#ifdef CONFIG_COMMON_CLK_DEBUG
+	struct dentry *d;
+	struct dentry *new_parent_d;
+#endif
+
+	if (!clk || !new_parent)
+		return;
+
+	hlist_del(&clk->child_node);
+
+	if (new_parent)
+		hlist_add_head(&clk->child_node, &new_parent->children);
+	else
+		hlist_add_head(&clk->child_node, &clk_orphan_list);
+
+#ifdef CONFIG_COMMON_CLK_DEBUG
+	if (!inited)
+		goto out;
+
+	if (new_parent)
+		new_parent_d = new_parent->dentry;
+	else
+		new_parent_d = orphandir;
+
+	d = debugfs_rename(clk->dentry->d_parent, clk->dentry,
+			new_parent_d, clk->name);
+	if (d)
+		clk->dentry = d;
+	else
+		pr_debug("%s: failed to rename debugfs entry for %s\n",
+				__func__, clk->name);
+out:
+#endif
+
+	clk->parent = new_parent;
+
+	__clk_recalc_rates(clk, POST_RATE_CHANGE);
+}
+
+static int __clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	struct clk *old_parent;
+	unsigned long flags;
+	int ret = -EINVAL;
+	u8 i;
+
+	old_parent = clk->parent;
+
+	/* find index of new parent clock using cached parent ptrs */
+	for (i = 0; i < clk->num_parents; i++)
+		if (clk->parents[i] == parent)
+			break;
+
+	/*
+	 * find index of new parent clock using string name comparison
+	 * also try to cache the parent to avoid future calls to __clk_lookup
+	 */
+	if (i == clk->num_parents)
+		for (i = 0; i < clk->num_parents; i++)
+			if (!strcmp(clk->parent_names[i], parent->name)) {
+				clk->parents[i] = __clk_lookup(parent->name);
+				break;
+			}
+
+	if (i == clk->num_parents) {
+		pr_debug("%s: clock %s is not a possible parent of clock %s\n",
+				__func__, parent->name, clk->name);
+		goto out;
+	}
+
+	/* migrate prepare and enable */
+	if (clk->prepare_count)
+		__clk_prepare(parent);
+
+	/* FIXME replace with clk_is_enabled(clk) someday */
+	spin_lock_irqsave(&enable_lock, flags);
+	if (clk->enable_count)
+		__clk_enable(parent);
+	spin_unlock_irqrestore(&enable_lock, flags);
+
+	/* change clock input source */
+	ret = clk->ops->set_parent(clk->hw, i);
+
+	/* clean up old prepare and enable */
+	spin_lock_irqsave(&enable_lock, flags);
+	if (clk->enable_count)
+		__clk_disable(old_parent);
+	spin_unlock_irqrestore(&enable_lock, flags);
+
+	if (clk->prepare_count)
+		__clk_unprepare(old_parent);
+
+out:
+	return ret;
+}
+
+/**
+ * clk_set_parent - switch the parent of a mux clk
+ * @clk: the mux clk whose input we are switching
+ * @parent: the new input to clk
+ *
+ * Re-parent clk to use parent as it's new input source.  If clk has the
+ * CLK_SET_PARENT_GATE flag set then clk must be gated for this
+ * operation to succeed.  After successfully changing clk's parent
+ * clk_set_parent will update the clk topology, sysfs topology and
+ * propagate rate recalculation via __clk_recalc_rates.  Returns 0 on
+ * success, -EERROR otherwise.
+ */
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	int ret = 0;
+
+	if (!clk || !clk->ops)
+		return -EINVAL;
+
+	if (!clk->ops->set_parent)
+		return -ENOSYS;
+
+	/* prevent racing with updates to the clock topology */
+	mutex_lock(&prepare_lock);
+
+	if (clk->parent == parent)
+		goto out;
+
+	/* propagate PRE_RATE_CHANGE notifications */
+	if (clk->notifier_count)
+		ret = __clk_speculate_rates(clk, parent->rate);
+
+	/* abort if a driver objects */
+	if (ret == NOTIFY_STOP)
+		goto out;
+
+	/* only re-parent if the clock is not in use */
+	if ((clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count)
+		ret = -EBUSY;
+	else
+		ret = __clk_set_parent(clk, parent);
+
+	/* propagate ABORT_RATE_CHANGE if .set_parent failed */
+	if (ret) {
+		__clk_recalc_rates(clk, ABORT_RATE_CHANGE);
+		goto out;
+	}
+
+	/* propagate rate recalculation downstream */
+	__clk_reparent(clk, parent);
+
+out:
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_parent);
+
+/**
+ * __clk_init - initialize the data structures in a struct clk
+ * @dev:	device initializing this clk, placeholder for now
+ * @clk:	clk being initialized
+ *
+ * Initializes the lists in struct clk, queries the hardware for the
+ * parent and rate and sets them both.
+ *
+ * Any struct clk passed into __clk_init must have the following members
+ * populated:
+ * 	.name
+ * 	.ops
+ * 	.hw
+ * 	.parent_names
+ * 	.num_parents
+ * 	.flags
+ *
+ * Essentially, everything that would normally be passed into clk_register is
+ * assumed to be initialized already in __clk_init.  The other members may be
+ * populated, but are optional.
+ *
+ * __clk_init is only exposed via clk-private.h and is intended for use with
+ * very large numbers of clocks that need to be statically initialized.  It is
+ * a layering violation to include clk-private.h from any code which implements
+ * a clock's .ops; as such any statically initialized clock data MUST be in a
+ * separate C file from the logic that implements it's operations.
+ */
+void __clk_init(struct device *dev, struct clk *clk)
+{
+	int i;
+	struct clk *orphan;
+	struct hlist_node *tmp, *tmp2;
+
+	if (!clk)
+		return;
+
+	mutex_lock(&prepare_lock);
+
+	/* check to see if a clock with this name is already registered */
+	if (__clk_lookup(clk->name))
+		goto out;
+
+	/* throw a WARN if any entries in parent_names are NULL */
+	for (i = 0; i < clk->num_parents; i++)
+		WARN(!clk->parent_names[i],
+				"%s: invalid NULL in %s's .parent_names\n",
+				__func__, clk->name);
+
+	/*
+	 * Allocate an array of struct clk *'s to avoid unnecessary string
+	 * look-ups of clk's possible parents.  This can fail for clocks passed
+	 * in to clk_init during early boot; thus any access to clk->parents[]
+	 * must always check for a NULL pointer and try to populate it if
+	 * necessary.
+	 *
+	 * If clk->parents is not NULL we skip this entire block.  This allows
+	 * for clock drivers to statically initialize clk->parents.
+	 */
+	if (clk->num_parents && !clk->parents) {
+		clk->parents = kmalloc((sizeof(struct clk*) * clk->num_parents),
+				GFP_KERNEL);
+		/*
+		 * __clk_lookup returns NULL for parents that have not been
+		 * clk_init'd; thus any access to clk->parents[] must check
+		 * for a NULL pointer.  We can always perform lazy lookups for
+		 * missing parents later on.
+		 */
+		if (clk->parents)
+			for (i = 0; i < clk->num_parents; i++)
+				clk->parents[i] =
+					__clk_lookup(clk->parent_names[i]);
+	}
+
+	clk->parent = __clk_init_parent(clk);
+
+	/*
+	 * Populate clk->parent if parent has already been __clk_init'd.  If
+	 * parent has not yet been __clk_init'd then place clk in the orphan
+	 * list.  If clk has set the CLK_IS_ROOT flag then place it in the root
+	 * clk list.
+	 *
+	 * Every time a new clk is clk_init'd then we walk the list of orphan
+	 * clocks and re-parent any that are children of the clock currently
+	 * being clk_init'd.
+	 */
+	if (clk->parent)
+		hlist_add_head(&clk->child_node,
+				&clk->parent->children);
+	else if (clk->flags & CLK_IS_ROOT)
+		hlist_add_head(&clk->child_node, &clk_root_list);
+	else
+		hlist_add_head(&clk->child_node, &clk_orphan_list);
+
+	/*
+	 * Set clk's rate.  The preferred method is to use .recalc_rate.  For
+	 * simple clocks and lazy developers the default fallback is to use the
+	 * parent's rate.  If a clock doesn't have a parent (or is orphaned)
+	 * then rate is set to zero.
+	 */
+	if (clk->ops->recalc_rate)
+		clk->rate = clk->ops->recalc_rate(clk->hw,
+				__clk_get_rate(clk->parent));
+	else if (clk->parent)
+		clk->rate = clk->parent->rate;
+	else
+		clk->rate = 0;
+
+	/*
+	 * walk the list of orphan clocks and reparent any that are children of
+	 * this clock
+	 */
+	hlist_for_each_entry_safe(orphan, tmp, tmp2, &clk_orphan_list, child_node)
+		for (i = 0; i < orphan->num_parents; i++)
+			if (!strcmp(clk->name, orphan->parent_names[i])) {
+				__clk_reparent(orphan, clk);
+				break;
+			}
+
+	/*
+	 * optional platform-specific magic
+	 *
+	 * The .init callback is not used by any of the basic clock types, but
+	 * exists for weird hardware that must perform initialization magic.
+	 * Please consider other ways of solving initialization problems before
+	 * using this callback, as it's use is discouraged.
+	 */
+	if (clk->ops->init)
+		clk->ops->init(clk->hw);
+
+	clk_debug_register(clk);
+
+out:
+	mutex_unlock(&prepare_lock);
+
+	return;
+}
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @name: clock name
+ * @ops: operations this clock supports
+ * @hw: link to hardware-specific clock data
+ * @parent_names: array of string names for all possible parents
+ * @num_parents: number of possible parents
+ * @flags: framework-level hints and quirks
+ *
+ * clk_register is the primary interface for populating the clock tree with new
+ * clock nodes.  It returns a pointer to the newly allocated struct clk which
+ * cannot be dereferenced by driver code but may be used in conjuction with the
+ * rest of the clock API.
+ */
+struct clk *clk_register(struct device *dev, const char *name,
+		const struct clk_ops *ops, struct clk_hw *hw,
+		char **parent_names, u8 num_parents, unsigned long flags)
+{
+	struct clk *clk;
+
+	clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+	if (!clk)
+		return NULL;
+
+	clk->name = name;
+	clk->ops = ops;
+	clk->hw = hw;
+	clk->flags = flags;
+	clk->parent_names = parent_names;
+	clk->num_parents = num_parents;
+	hw->clk = clk;
+
+	__clk_init(dev, clk);
+
+	return clk;
+}
+EXPORT_SYMBOL_GPL(clk_register);
+
+/***        clk rate change notifiers        ***/
+
+/**
+ * clk_notifier_register - add a clk rate change notifier
+ * @clk: struct clk * to watch
+ * @nb: struct notifier_block * with callback info
+ *
+ * Request notification when clk's rate changes.  This uses an SRCU
+ * notifier because we want it to block and notifier unregistrations are
+ * uncommon.  The callbacks associated with the notifier must not
+ * re-enter into the clk framework by calling any top-level clk APIs;
+ * this will cause a nested prepare_lock mutex.
+ *
+ * Pre-change notifier callbacks will be passed the current, pre-change
+ * rate of the clk via struct clk_notifier_data.old_rate.  The new,
+ * post-change rate of the clk is passed via struct
+ * clk_notifier_data.new_rate.
+ *
+ * Post-change notifiers will pass the now-current, post-change rate of
+ * the clk in both struct clk_notifier_data.old_rate and struct
+ * clk_notifier_data.new_rate.
+ *
+ * Abort-change notifiers are effectively the opposite of pre-change
+ * notifiers: the original pre-change clk rate is passed in via struct
+ * clk_notifier_data.new_rate and the failed post-change rate is passed
+ * in via struct clk_notifier_data.old_rate.
+ *
+ * clk_notifier_register() must be called from non-atomic context.
+ * Returns -EINVAL if called with null arguments, -ENOMEM upon
+ * allocation failure; otherwise, passes along the return value of
+ * srcu_notifier_chain_register().
+ */
+int clk_notifier_register(struct clk *clk, struct notifier_block *nb)
+{
+	struct clk_notifier *cn;
+	int ret = -ENOMEM;
+
+	if (!clk || !nb)
+		return -EINVAL;
+
+	mutex_lock(&prepare_lock);
+
+	/* search the list of notifiers for this clk */
+	list_for_each_entry(cn, &clk_notifier_list, node)
+		if (cn->clk == clk)
+			break;
+
+	/* if clk wasn't in the notifier list, allocate new clk_notifier */
+	if (cn->clk != clk) {
+		cn = kzalloc(sizeof(struct clk_notifier), GFP_KERNEL);
+		if (!cn)
+			goto out;
+
+		cn->clk = clk;
+		srcu_init_notifier_head(&cn->notifier_head);
+
+		list_add(&cn->node, &clk_notifier_list);
+	}
+
+	ret = srcu_notifier_chain_register(&cn->notifier_head, nb);
+
+	clk->notifier_count++;
+
+out:
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_notifier_register);
+
+/**
+ * clk_notifier_unregister - remove a clk rate change notifier
+ * @clk: struct clk *
+ * @nb: struct notifier_block * with callback info
+ *
+ * Request no further notification for changes to 'clk' and frees memory
+ * allocated in clk_notifier_register.
+ *
+ * Returns -EINVAL if called with null arguments; otherwise, passes
+ * along the return value of srcu_notifier_chain_unregister().
+ */
+int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
+{
+	struct clk_notifier *cn = NULL;
+	int ret = -EINVAL;
+
+	if (!clk || !nb)
+		return -EINVAL;
+
+	mutex_lock(&prepare_lock);
+
+	list_for_each_entry(cn, &clk_notifier_list, node)
+		if (cn->clk == clk)
+			break;
+
+	if (cn->clk == clk) {
+		ret = srcu_notifier_chain_unregister(&cn->notifier_head, nb);
+
+		clk->notifier_count--;
+
+		/* XXX the notifier code should handle this better */
+		if (!cn->notifier_head.head) {
+			srcu_cleanup_notifier_head(&cn->notifier_head);
+			kfree(cn);
+		}
+
+	} else {
+		ret = -ENOENT;
+	}
+
+	mutex_unlock(&prepare_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clk_notifier_unregister);
diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h
new file mode 100644
index 0000000..e2cce6f
--- /dev/null
+++ b/include/linux/clk-private.h
@@ -0,0 +1,72 @@
+/*
+ *  linux/include/linux/clk-private.h
+ *
+ *  Copyright (c) 2010-2011 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *  Copyright (C) 2011-2012 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.
+ */
+#ifndef __LINUX_CLK_PRIVATE_H
+#define __LINUX_CLK_PRIVATE_H
+
+#include <linux/clk-provider.h>
+#include <linux/list.h>
+
+/*
+ * WARNING: Do not include clk-private.h from any file that implements struct
+ * clk_ops.  Doing so is a layering violation!
+ *
+ * This header exists only to allow for statically initialized clock data.  Any
+ * static clock data must be defined in a separate file from the logic that
+ * implements the clock operations for that same data.
+ */
+
+#ifdef CONFIG_COMMON_CLK
+
+struct clk {
+	const char		*name;
+	const struct clk_ops	*ops;
+	struct clk_hw		*hw;
+	struct clk		*parent;
+	char			**parent_names;
+	struct clk		**parents;
+	u8			num_parents;
+	unsigned long		rate;
+	unsigned long		new_rate;
+	unsigned long		flags;
+	unsigned int		enable_count;
+	unsigned int		prepare_count;
+	struct hlist_head	children;
+	struct hlist_node	child_node;
+	unsigned int		notifier_count;
+#ifdef CONFIG_COMMON_CLK_DEBUG
+	struct dentry		*dentry;
+#endif
+};
+
+/**
+ * __clk_init - initialize the data structures in a struct clk
+ * @dev:	device initializing this clk, placeholder for now
+ * @clk:	clk being initialized
+ *
+ * Initializes the lists in struct clk, queries the hardware for the
+ * parent and rate and sets them both.
+ *
+ * Any struct clk passed into __clk_init must have the following members
+ * populated:
+ * 	.name
+ * 	.ops
+ * 	.hw
+ * 	.parent_names
+ * 	.num_parents
+ * 	.flags
+ *
+ * It is not necessary to call clk_register if __clk_init is used directly with
+ * statically initialized clock data.
+ */
+void __clk_init(struct device *dev, struct clk *clk);
+
+#endif /* CONFIG_COMMON_CLK */
+#endif /* CLK_PRIVATE_H */
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
new file mode 100644
index 0000000..b18b0e7
--- /dev/null
+++ b/include/linux/clk-provider.h
@@ -0,0 +1,173 @@
+/*
+ *  linux/include/linux/clk-provider.h
+ *
+ *  Copyright (c) 2010-2011 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *  Copyright (C) 2011-2012 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.
+ */
+#ifndef __LINUX_CLK_PROVIDER_H
+#define __LINUX_CLK_PROVIDER_H
+
+#include <linux/clk.h>
+
+#ifdef CONFIG_COMMON_CLK
+
+/**
+ * struct clk_hw - handle for traversing from a struct clk to its corresponding
+ * hardware-specific structure.  struct clk_hw should be declared within struct
+ * clk_foo and then referenced by the struct clk instance that uses struct
+ * clk_foo's clk_ops
+ *
+ * clk: pointer to the struct clk instance that points back to this struct
+ * clk_hw instance
+ */
+struct clk_hw {
+	struct clk *clk;
+};
+
+/*
+ * flags used across common struct clk.  these flags should only affect the
+ * top-level framework.  custom flags for dealing with hardware specifics
+ * belong in struct clk_foo
+ */
+#define CLK_SET_RATE_GATE	BIT(0) /* must be gated across rate change */
+#define CLK_SET_PARENT_GATE	BIT(1) /* must be gated across re-parent */
+#define CLK_SET_RATE_PARENT	BIT(2) /* propagate rate change up one level */
+#define CLK_IGNORE_UNUSED	BIT(3) /* do not gate even if unused */
+#define CLK_IS_ROOT		BIT(4) /* root clk, has no parent */
+
+/**
+ * struct clk_ops -  Callback operations for hardware clocks; these are to
+ * be provided by the clock implementation, and will be called by drivers
+ * through the clk_* api.
+ *
+ * @prepare:	Prepare the clock for enabling. This must not return until
+ * 		the clock is fully prepared, and it's safe to call clk_enable.
+ * 		This callback is intended to allow clock implementations to
+ * 		do any initialisation that may sleep. Called with
+ * 		prepare_lock held.
+ *
+ * @unprepare:	Release the clock from its prepared state. This will typically
+ * 		undo any work done in the @prepare callback. Called with
+ * 		prepare_lock held.
+ *
+ * @enable:	Enable the clock atomically. This must not return until the
+ * 		clock is generating a valid clock signal, usable by consumer
+ * 		devices. Called with enable_lock held. This function must not
+ * 		sleep.
+ *
+ * @disable:	Disable the clock atomically. Called with enable_lock held.
+ * 		This function must not sleep.
+ *
+ * @recalc_rate	Recalculate the rate of this clock, by quering hardware.  The
+ * 		parent rate is an input parameter.  It is up to the caller to
+ * 		insure that the prepare_mutex is held across this call.
+ * 		Returns the calculated rate.  Optional, but recommended - if
+ * 		this op is not set then clock rate will be initialized to 0.
+ *
+ * @round_rate:	Given a target rate as input, returns the closest rate actually
+ * 		supported by the clock.
+ *
+ * @get_parent:	Queries the hardware to determine the parent of a clock.  The
+ * 		return value is a u8 which specifies the index corresponding to
+ * 		the parent clock.  This index can be applied to either the
+ * 		.parent_names or .parents arrays.  In short, this function
+ * 		translates the parent value read from hardware into an array
+ * 		index.  Currently only called when the clock is initialized by
+ * 		__clk_init.  This callback is mandatory for clocks with
+ * 		multiple parents.  It is optional (and unnecessary) for clocks
+ * 		with 0 or 1 parents.
+ *
+ * @set_parent:	Change the input source of this clock; for clocks with multiple
+ * 		possible parents specify a new parent by passing in the index
+ * 		as a u8 corresponding to the parent in either the .parent_names
+ * 		or .parents arrays.  This function in affect translates an
+ * 		array index into the value programmed into the hardware.
+ * 		Returns 0 on success, -EERROR otherwise.
+ *
+ * @set_rate:	Change the rate of this clock. If this callback returns
+ * 		CLK_SET_RATE_PARENT, the rate change will be propagated to the
+ * 		parent clock (which may propagate again if the parent clock
+ * 		also sets this flag). The requested rate of the parent is
+ * 		passed back from the callback in the second 'unsigned long *'
+ * 		argument.  Note that it is up to the hardware clock's set_rate
+ * 		implementation to insure that clocks do not run out of spec
+ * 		when propgating the call to set_rate up to the parent.  One way
+ * 		to do this is to gate the clock (via clk_disable and/or
+ * 		clk_unprepare) before calling clk_set_rate, then ungating it
+ * 		afterward.  If your clock also has the CLK_GATE_SET_RATE flag
+ * 		set then this will insure safety.  Returns 0 on success,
+ * 		-EERROR otherwise.
+ *
+ * The clk_enable/clk_disable and clk_prepare/clk_unprepare pairs allow
+ * implementations to split any work between atomic (enable) and sleepable
+ * (prepare) contexts.  If enabling a clock requires code that might sleep,
+ * this must be done in clk_prepare.  Clock enable code that will never be
+ * called in a sleepable context may be implement in clk_enable.
+ *
+ * Typically, drivers will call clk_prepare when a clock may be needed later
+ * (eg. when a device is opened), and clk_enable when the clock is actually
+ * required (eg. from an interrupt). Note that clk_prepare MUST have been
+ * called before clk_enable.
+ */
+struct clk_ops {
+	int		(*prepare)(struct clk_hw *hw);
+	void		(*unprepare)(struct clk_hw *hw);
+	int		(*enable)(struct clk_hw *hw);
+	void		(*disable)(struct clk_hw *hw);
+	int		(*is_enabled)(struct clk_hw *hw);
+	unsigned long	(*recalc_rate)(struct clk_hw *hw,
+					unsigned long parent_rate);
+	long		(*round_rate)(struct clk_hw *hw, unsigned long,
+					unsigned long *);
+	int		(*set_parent)(struct clk_hw *hw, u8 index);
+	u8		(*get_parent)(struct clk_hw *hw);
+	int		(*set_rate)(struct clk_hw *hw, unsigned long);
+	void		(*init)(struct clk_hw *hw);
+};
+
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @name: clock name
+ * @ops: operations this clock supports
+ * @hw: link to hardware-specific clock data
+ * @parent_names: array of string names for all possible parents
+ * @num_parents: number of possible parents
+ * @flags: framework-level hints and quirks
+ *
+ * clk_register is the primary interface for populating the clock tree with new
+ * clock nodes.  It returns a pointer to the newly allocated struct clk which
+ * cannot be dereferenced by driver code but may be used in conjuction with the
+ * rest of the clock API.
+ */
+struct clk *clk_register(struct device *dev, const char *name,
+		const struct clk_ops *ops, struct clk_hw *hw,
+		char **parent_names, u8 num_parents, unsigned long flags);
+
+/* helper functions */
+const char *__clk_get_name(struct clk *clk);
+struct clk_hw *__clk_get_hw(struct clk *clk);
+u8 __clk_get_num_parents(struct clk *clk);
+struct clk *__clk_get_parent(struct clk *clk);
+inline int __clk_get_enable_count(struct clk *clk);
+inline int __clk_get_prepare_count(struct clk *clk);
+unsigned long __clk_get_rate(struct clk *clk);
+unsigned long __clk_get_flags(struct clk *clk);
+int __clk_is_enabled(struct clk *clk);
+struct clk *__clk_lookup(const char *name);
+
+/*
+ * FIXME clock api without lock protection
+ */
+int __clk_prepare(struct clk *clk);
+void __clk_unprepare(struct clk *clk);
+void __clk_reparent(struct clk *clk, struct clk *new_parent);
+unsigned long __clk_round_rate(struct clk *clk, unsigned long rate);
+
+#endif /* CONFIG_COMMON_CLK */
+#endif /* CLK_PROVIDER_H */
diff --git a/include/linux/clk.h b/include/linux/clk.h
index b9d46fa..b025272 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -3,6 +3,7 @@
  *
  *  Copyright (C) 2004 ARM Limited.
  *  Written by Deep Blue Solutions Limited.
+ *  Copyright (C) 2011-2012 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
@@ -12,18 +13,75 @@
 #define __LINUX_CLK_H
 
 #include <linux/kernel.h>
+#include <linux/notifier.h>
 
 struct device;
 
-/*
- * The base API.
+struct clk;
+
+#ifdef CONFIG_COMMON_CLK
+
+/**
+ * DOC: clk notifier callback types
+ *
+ * PRE_RATE_CHANGE - called immediately before the clk rate is changed,
+ *     to indicate that the rate change will proceed.  Drivers must
+ *     immediately terminate any operations that will be affected by the
+ *     rate change.  Callbacks may either return NOTIFY_DONE or
+ *     NOTIFY_STOP.
+ *
+ * ABORT_RATE_CHANGE: called if the rate change failed for some reason
+ *     after PRE_RATE_CHANGE.  In this case, all registered notifiers on
+ *     the clk will be called with ABORT_RATE_CHANGE. Callbacks must
+ *     always return NOTIFY_DONE.
+ *
+ * POST_RATE_CHANGE - called after the clk rate change has successfully
+ *     completed.  Callbacks must always return NOTIFY_DONE.
+ *
  */
+#define PRE_RATE_CHANGE			BIT(0)
+#define POST_RATE_CHANGE		BIT(1)
+#define ABORT_RATE_CHANGE		BIT(2)
 
+/**
+ * struct clk_notifier - associate a clk with a notifier
+ * @clk: struct clk * to associate the notifier with
+ * @notifier_head: a blocking_notifier_head for this clk
+ * @node: linked list pointers
+ *
+ * A list of struct clk_notifier is maintained by the notifier code.
+ * An entry is created whenever code registers the first notifier on a
+ * particular @clk.  Future notifiers on that @clk are added to the
+ * @notifier_head.
+ */
+struct clk_notifier {
+	struct clk			*clk;
+	struct srcu_notifier_head	notifier_head;
+	struct list_head		node;
+};
 
-/*
- * struct clk - an machine class defined object / cookie.
+/**
+ * struct clk_notifier_data - rate data to pass to the notifier callback
+ * @clk: struct clk * being changed
+ * @old_rate: previous rate of this clk
+ * @new_rate: new rate of this clk
+ *
+ * For a pre-notifier, old_rate is the clk's rate before this rate
+ * change, and new_rate is what the rate will be in the future.  For a
+ * post-notifier, old_rate and new_rate are both set to the clk's
+ * current rate (this was done to optimize the implementation).
  */
-struct clk;
+struct clk_notifier_data {
+	struct clk		*clk;
+	unsigned long		old_rate;
+	unsigned long		new_rate;
+};
+
+int clk_notifier_register(struct clk *clk, struct notifier_block *nb);
+
+int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb);
+
+#endif /* !CONFIG_COMMON_CLK */
 
 /**
  * clk_get - lookup and obtain a reference to a clock producer.
