v4.19.13 snapshot.
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
new file mode 100644
index 0000000..d31055a
--- /dev/null
+++ b/drivers/clk/clk.c
@@ -0,0 +1,4179 @@
+/*
+ * 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/driver-api/clk.rst
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clk/clk-conf.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>
+#include <linux/of.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/pm_runtime.h>
+#include <linux/sched.h>
+#include <linux/clkdev.h>
+
+#include "clk.h"
+
+static DEFINE_SPINLOCK(enable_lock);
+static DEFINE_MUTEX(prepare_lock);
+
+static struct task_struct *prepare_owner;
+static struct task_struct *enable_owner;
+
+static int prepare_refcnt;
+static int enable_refcnt;
+
+static HLIST_HEAD(clk_root_list);
+static HLIST_HEAD(clk_orphan_list);
+static LIST_HEAD(clk_notifier_list);
+
+/*** private data structures ***/
+
+struct clk_core {
+ const char *name;
+ const struct clk_ops *ops;
+ struct clk_hw *hw;
+ struct module *owner;
+ struct device *dev;
+ struct clk_core *parent;
+ const char **parent_names;
+ struct clk_core **parents;
+ u8 num_parents;
+ u8 new_parent_index;
+ unsigned long rate;
+ unsigned long req_rate;
+ unsigned long new_rate;
+ struct clk_core *new_parent;
+ struct clk_core *new_child;
+ unsigned long flags;
+ bool orphan;
+ unsigned int enable_count;
+ unsigned int prepare_count;
+ unsigned int protect_count;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ unsigned long accuracy;
+ int phase;
+ struct clk_duty duty;
+ struct hlist_head children;
+ struct hlist_node child_node;
+ struct hlist_head clks;
+ unsigned int notifier_count;
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *dentry;
+ struct hlist_node debug_node;
+#endif
+ struct kref ref;
+};
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/clk.h>
+
+struct clk {
+ struct clk_core *core;
+ const char *dev_id;
+ const char *con_id;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ unsigned int exclusive_count;
+ struct hlist_node clks_node;
+};
+
+/*** runtime pm ***/
+static int clk_pm_runtime_get(struct clk_core *core)
+{
+ int ret = 0;
+
+ if (!core->dev)
+ return 0;
+
+ ret = pm_runtime_get_sync(core->dev);
+ return ret < 0 ? ret : 0;
+}
+
+static void clk_pm_runtime_put(struct clk_core *core)
+{
+ if (!core->dev)
+ return;
+
+ pm_runtime_put_sync(core->dev);
+}
+
+/*** locking ***/
+static void clk_prepare_lock(void)
+{
+ if (!mutex_trylock(&prepare_lock)) {
+ if (prepare_owner == current) {
+ prepare_refcnt++;
+ return;
+ }
+ mutex_lock(&prepare_lock);
+ }
+ WARN_ON_ONCE(prepare_owner != NULL);
+ WARN_ON_ONCE(prepare_refcnt != 0);
+ prepare_owner = current;
+ prepare_refcnt = 1;
+}
+
+static void clk_prepare_unlock(void)
+{
+ WARN_ON_ONCE(prepare_owner != current);
+ WARN_ON_ONCE(prepare_refcnt == 0);
+
+ if (--prepare_refcnt)
+ return;
+ prepare_owner = NULL;
+ mutex_unlock(&prepare_lock);
+}
+
+static unsigned long clk_enable_lock(void)
+ __acquires(enable_lock)
+{
+ unsigned long flags;
+
+ /*
+ * On UP systems, spin_trylock_irqsave() always returns true, even if
+ * we already hold the lock. So, in that case, we rely only on
+ * reference counting.
+ */
+ if (!IS_ENABLED(CONFIG_SMP) ||
+ !spin_trylock_irqsave(&enable_lock, flags)) {
+ if (enable_owner == current) {
+ enable_refcnt++;
+ __acquire(enable_lock);
+ if (!IS_ENABLED(CONFIG_SMP))
+ local_save_flags(flags);
+ return flags;
+ }
+ spin_lock_irqsave(&enable_lock, flags);
+ }
+ WARN_ON_ONCE(enable_owner != NULL);
+ WARN_ON_ONCE(enable_refcnt != 0);
+ enable_owner = current;
+ enable_refcnt = 1;
+ return flags;
+}
+
+static void clk_enable_unlock(unsigned long flags)
+ __releases(enable_lock)
+{
+ WARN_ON_ONCE(enable_owner != current);
+ WARN_ON_ONCE(enable_refcnt == 0);
+
+ if (--enable_refcnt) {
+ __release(enable_lock);
+ return;
+ }
+ enable_owner = NULL;
+ spin_unlock_irqrestore(&enable_lock, flags);
+}
+
+static bool clk_core_rate_is_protected(struct clk_core *core)
+{
+ return core->protect_count;
+}
+
+static bool clk_core_is_prepared(struct clk_core *core)
+{
+ bool ret = false;
+
+ /*
+ * .is_prepared is optional for clocks that can prepare
+ * fall back to software usage counter if it is missing
+ */
+ if (!core->ops->is_prepared)
+ return core->prepare_count;
+
+ if (!clk_pm_runtime_get(core)) {
+ ret = core->ops->is_prepared(core->hw);
+ clk_pm_runtime_put(core);
+ }
+
+ return ret;
+}
+
+static bool clk_core_is_enabled(struct clk_core *core)
+{
+ bool ret = false;
+
+ /*
+ * .is_enabled is only mandatory for clocks that gate
+ * fall back to software usage counter if .is_enabled is missing
+ */
+ if (!core->ops->is_enabled)
+ return core->enable_count;
+
+ /*
+ * Check if clock controller's device is runtime active before
+ * calling .is_enabled callback. If not, assume that clock is
+ * disabled, because we might be called from atomic context, from
+ * which pm_runtime_get() is not allowed.
+ * This function is called mainly from clk_disable_unused_subtree,
+ * which ensures proper runtime pm activation of controller before
+ * taking enable spinlock, but the below check is needed if one tries
+ * to call it from other places.
+ */
+ if (core->dev) {
+ pm_runtime_get_noresume(core->dev);
+ if (!pm_runtime_active(core->dev)) {
+ ret = false;
+ goto done;
+ }
+ }
+
+ ret = core->ops->is_enabled(core->hw);
+done:
+ if (core->dev)
+ pm_runtime_put(core->dev);
+
+ return ret;
+}
+
+/*** helper functions ***/
+
+const char *__clk_get_name(const struct clk *clk)
+{
+ return !clk ? NULL : clk->core->name;
+}
+EXPORT_SYMBOL_GPL(__clk_get_name);
+
+const char *clk_hw_get_name(const struct clk_hw *hw)
+{
+ return hw->core->name;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_name);
+
+struct clk_hw *__clk_get_hw(struct clk *clk)
+{
+ return !clk ? NULL : clk->core->hw;
+}
+EXPORT_SYMBOL_GPL(__clk_get_hw);
+
+unsigned int clk_hw_get_num_parents(const struct clk_hw *hw)
+{
+ return hw->core->num_parents;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_num_parents);
+
+struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
+{
+ return hw->core->parent ? hw->core->parent->hw : NULL;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_parent);
+
+static struct clk_core *__clk_lookup_subtree(const char *name,
+ struct clk_core *core)
+{
+ struct clk_core *child;
+ struct clk_core *ret;
+
+ if (!strcmp(core->name, name))
+ return core;
+
+ hlist_for_each_entry(child, &core->children, child_node) {
+ ret = __clk_lookup_subtree(name, child);
+ if (ret)
+ return ret;
+ }
+
+ return NULL;
+}
+
+static struct clk_core *clk_core_lookup(const char *name)
+{
+ struct clk_core *root_clk;
+ struct clk_core *ret;
+
+ if (!name)
+ return NULL;
+
+ /* search the 'proper' clk tree first */
+ hlist_for_each_entry(root_clk, &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, &clk_orphan_list, child_node) {
+ ret = __clk_lookup_subtree(name, root_clk);
+ if (ret)
+ return ret;
+ }
+
+ return NULL;
+}
+
+static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
+ u8 index)
+{
+ if (!core || index >= core->num_parents)
+ return NULL;
+
+ if (!core->parents[index])
+ core->parents[index] =
+ clk_core_lookup(core->parent_names[index]);
+
+ return core->parents[index];
+}
+
+struct clk_hw *
+clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index)
+{
+ struct clk_core *parent;
+
+ parent = clk_core_get_parent_by_index(hw->core, index);
+
+ return !parent ? NULL : parent->hw;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_parent_by_index);
+
+unsigned int __clk_get_enable_count(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->enable_count;
+}
+
+static unsigned long clk_core_get_rate_nolock(struct clk_core *core)
+{
+ unsigned long ret;
+
+ if (!core) {
+ ret = 0;
+ goto out;
+ }
+
+ ret = core->rate;
+
+ if (!core->num_parents)
+ goto out;
+
+ if (!core->parent)
+ ret = 0;
+
+out:
+ return ret;
+}
+
+unsigned long clk_hw_get_rate(const struct clk_hw *hw)
+{
+ return clk_core_get_rate_nolock(hw->core);
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_rate);
+
+static unsigned long __clk_get_accuracy(struct clk_core *core)
+{
+ if (!core)
+ return 0;
+
+ return core->accuracy;
+}
+
+unsigned long __clk_get_flags(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->flags;
+}
+EXPORT_SYMBOL_GPL(__clk_get_flags);
+
+unsigned long clk_hw_get_flags(const struct clk_hw *hw)
+{
+ return hw->core->flags;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_flags);
+
+bool clk_hw_is_prepared(const struct clk_hw *hw)
+{
+ return clk_core_is_prepared(hw->core);
+}
+
+bool clk_hw_rate_is_protected(const struct clk_hw *hw)
+{
+ return clk_core_rate_is_protected(hw->core);
+}
+
+bool clk_hw_is_enabled(const struct clk_hw *hw)
+{
+ return clk_core_is_enabled(hw->core);
+}
+
+bool __clk_is_enabled(struct clk *clk)
+{
+ if (!clk)
+ return false;
+
+ return clk_core_is_enabled(clk->core);
+}
+EXPORT_SYMBOL_GPL(__clk_is_enabled);
+
+static bool mux_is_better_rate(unsigned long rate, unsigned long now,
+ unsigned long best, unsigned long flags)
+{
+ if (flags & CLK_MUX_ROUND_CLOSEST)
+ return abs(now - rate) < abs(best - rate);
+
+ return now <= rate && now > best;
+}
+
+int clk_mux_determine_rate_flags(struct clk_hw *hw,
+ struct clk_rate_request *req,
+ unsigned long flags)
+{
+ struct clk_core *core = hw->core, *parent, *best_parent = NULL;
+ int i, num_parents, ret;
+ unsigned long best = 0;
+ struct clk_rate_request parent_req = *req;
+
+ /* if NO_REPARENT flag set, pass through to current parent */
+ if (core->flags & CLK_SET_RATE_NO_REPARENT) {
+ parent = core->parent;
+ if (core->flags & CLK_SET_RATE_PARENT) {
+ ret = __clk_determine_rate(parent ? parent->hw : NULL,
+ &parent_req);
+ if (ret)
+ return ret;
+
+ best = parent_req.rate;
+ } else if (parent) {
+ best = clk_core_get_rate_nolock(parent);
+ } else {
+ best = clk_core_get_rate_nolock(core);
+ }
+
+ goto out;
+ }
+
+ /* find the parent that can provide the fastest rate <= rate */
+ num_parents = core->num_parents;
+ for (i = 0; i < num_parents; i++) {
+ parent = clk_core_get_parent_by_index(core, i);
+ if (!parent)
+ continue;
+
+ if (core->flags & CLK_SET_RATE_PARENT) {
+ parent_req = *req;
+ ret = __clk_determine_rate(parent->hw, &parent_req);
+ if (ret)
+ continue;
+ } else {
+ parent_req.rate = clk_core_get_rate_nolock(parent);
+ }
+
+ if (mux_is_better_rate(req->rate, parent_req.rate,
+ best, flags)) {
+ best_parent = parent;
+ best = parent_req.rate;
+ }
+ }
+
+ if (!best_parent)
+ return -EINVAL;
+
+out:
+ if (best_parent)
+ req->best_parent_hw = best_parent->hw;
+ req->best_parent_rate = best;
+ req->rate = best;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_mux_determine_rate_flags);
+
+struct clk *__clk_lookup(const char *name)
+{
+ struct clk_core *core = clk_core_lookup(name);
+
+ return !core ? NULL : core->hw->clk;
+}
+
+static void clk_core_get_boundaries(struct clk_core *core,
+ unsigned long *min_rate,
+ unsigned long *max_rate)
+{
+ struct clk *clk_user;
+
+ *min_rate = core->min_rate;
+ *max_rate = core->max_rate;
+
+ hlist_for_each_entry(clk_user, &core->clks, clks_node)
+ *min_rate = max(*min_rate, clk_user->min_rate);
+
+ hlist_for_each_entry(clk_user, &core->clks, clks_node)
+ *max_rate = min(*max_rate, clk_user->max_rate);
+}
+
+void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
+ unsigned long max_rate)
+{
+ hw->core->min_rate = min_rate;
+ hw->core->max_rate = max_rate;
+}
+EXPORT_SYMBOL_GPL(clk_hw_set_rate_range);
+
+/*
+ * Helper for finding best parent to provide a given frequency. This can be used
+ * directly as a determine_rate callback (e.g. for a mux), or from a more
+ * complex clock that may combine a mux with other operations.
+ */
+int __clk_mux_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ return clk_mux_determine_rate_flags(hw, req, 0);
+}
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
+
+int __clk_mux_determine_rate_closest(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST);
+}
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
+
+/*** clk api ***/
+
+static void clk_core_rate_unprotect(struct clk_core *core)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (WARN(core->protect_count == 0,
+ "%s already unprotected\n", core->name))
+ return;
+
+ if (--core->protect_count > 0)
+ return;
+
+ clk_core_rate_unprotect(core->parent);
+}
+
+static int clk_core_rate_nuke_protect(struct clk_core *core)
+{
+ int ret;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return -EINVAL;
+
+ if (core->protect_count == 0)
+ return 0;
+
+ ret = core->protect_count;
+ core->protect_count = 1;
+ clk_core_rate_unprotect(core);
+
+ return ret;
+}
+
+/**
+ * clk_rate_exclusive_put - release exclusivity over clock rate control
+ * @clk: the clk over which the exclusivity is released
+ *
+ * clk_rate_exclusive_put() completes a critical section during which a clock
+ * consumer cannot tolerate any other consumer making any operation on the
+ * clock which could result in a rate change or rate glitch. Exclusive clocks
+ * cannot have their rate changed, either directly or indirectly due to changes
+ * further up the parent chain of clocks. As a result, clocks up parent chain
+ * also get under exclusive control of the calling consumer.
+ *
+ * If exlusivity is claimed more than once on clock, even by the same consumer,
+ * the rate effectively gets locked as exclusivity can't be preempted.
+ *
+ * Calls to clk_rate_exclusive_put() must be balanced with calls to
+ * clk_rate_exclusive_get(). Calls to this function may sleep, and do not return
+ * error status.
+ */
+void clk_rate_exclusive_put(struct clk *clk)
+{
+ if (!clk)
+ return;
+
+ clk_prepare_lock();
+
+ /*
+ * if there is something wrong with this consumer protect count, stop
+ * here before messing with the provider
+ */
+ if (WARN_ON(clk->exclusive_count <= 0))
+ goto out;
+
+ clk_core_rate_unprotect(clk->core);
+ clk->exclusive_count--;
+out:
+ clk_prepare_unlock();
+}
+EXPORT_SYMBOL_GPL(clk_rate_exclusive_put);
+
+static void clk_core_rate_protect(struct clk_core *core)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (core->protect_count == 0)
+ clk_core_rate_protect(core->parent);
+
+ core->protect_count++;
+}
+
+static void clk_core_rate_restore_protect(struct clk_core *core, int count)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (count == 0)
+ return;
+
+ clk_core_rate_protect(core);
+ core->protect_count = count;
+}
+
+/**
+ * clk_rate_exclusive_get - get exclusivity over the clk rate control
+ * @clk: the clk over which the exclusity of rate control is requested
+ *
+ * clk_rate_exlusive_get() begins a critical section during which a clock
+ * consumer cannot tolerate any other consumer making any operation on the
+ * clock which could result in a rate change or rate glitch. Exclusive clocks
+ * cannot have their rate changed, either directly or indirectly due to changes
+ * further up the parent chain of clocks. As a result, clocks up parent chain
+ * also get under exclusive control of the calling consumer.
+ *
+ * If exlusivity is claimed more than once on clock, even by the same consumer,
+ * the rate effectively gets locked as exclusivity can't be preempted.
+ *
+ * Calls to clk_rate_exclusive_get() should be balanced with calls to
+ * clk_rate_exclusive_put(). Calls to this function may sleep.
+ * Returns 0 on success, -EERROR otherwise
+ */
+int clk_rate_exclusive_get(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ clk_prepare_lock();
+ clk_core_rate_protect(clk->core);
+ clk->exclusive_count++;
+ clk_prepare_unlock();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clk_rate_exclusive_get);
+
+static void clk_core_unprepare(struct clk_core *core)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return;
+
+ if (WARN(core->prepare_count == 0,
+ "%s already unprepared\n", core->name))
+ return;
+
+ if (WARN(core->prepare_count == 1 && core->flags & CLK_IS_CRITICAL,
+ "Unpreparing critical %s\n", core->name))
+ return;
+
+ if (core->flags & CLK_SET_RATE_GATE)
+ clk_core_rate_unprotect(core);
+
+ if (--core->prepare_count > 0)
+ return;
+
+ WARN(core->enable_count > 0, "Unpreparing enabled %s\n", core->name);
+
+ trace_clk_unprepare(core);
+
+ if (core->ops->unprepare)
+ core->ops->unprepare(core->hw);
+
+ clk_pm_runtime_put(core);
+
+ trace_clk_unprepare_complete(core);
+ clk_core_unprepare(core->parent);
+}
+
+static void clk_core_unprepare_lock(struct clk_core *core)
+{
+ clk_prepare_lock();
+ clk_core_unprepare(core);
+ clk_prepare_unlock();
+}
+
+/**
+ * clk_unprepare - undo preparation of a clock source
+ * @clk: the clk being unprepared
+ *
+ * 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)
+{
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
+ clk_core_unprepare_lock(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_unprepare);
+
+static int clk_core_prepare(struct clk_core *core)
+{
+ int ret = 0;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ if (core->prepare_count == 0) {
+ ret = clk_pm_runtime_get(core);
+ if (ret)
+ return ret;
+
+ ret = clk_core_prepare(core->parent);
+ if (ret)
+ goto runtime_put;
+
+ trace_clk_prepare(core);
+
+ if (core->ops->prepare)
+ ret = core->ops->prepare(core->hw);
+
+ trace_clk_prepare_complete(core);
+
+ if (ret)
+ goto unprepare;
+ }
+
+ core->prepare_count++;
+
+ /*
+ * CLK_SET_RATE_GATE is a special case of clock protection
+ * Instead of a consumer claiming exclusive rate control, it is
+ * actually the provider which prevents any consumer from making any
+ * operation which could result in a rate change or rate glitch while
+ * the clock is prepared.
+ */
+ if (core->flags & CLK_SET_RATE_GATE)
+ clk_core_rate_protect(core);
+
+ return 0;
+unprepare:
+ clk_core_unprepare(core->parent);
+runtime_put:
+ clk_pm_runtime_put(core);
+ return ret;
+}
+
+static int clk_core_prepare_lock(struct clk_core *core)
+{
+ int ret;
+
+ clk_prepare_lock();
+ ret = clk_core_prepare(core);
+ clk_prepare_unlock();
+
+ return ret;
+}
+
+/**
+ * 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)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_prepare_lock(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_prepare);
+
+static void clk_core_disable(struct clk_core *core)
+{
+ lockdep_assert_held(&enable_lock);
+
+ if (!core)
+ return;
+
+ if (WARN(core->enable_count == 0, "%s already disabled\n", core->name))
+ return;
+
+ if (WARN(core->enable_count == 1 && core->flags & CLK_IS_CRITICAL,
+ "Disabling critical %s\n", core->name))
+ return;
+
+ if (--core->enable_count > 0)
+ return;
+
+ trace_clk_disable_rcuidle(core);
+
+ if (core->ops->disable)
+ core->ops->disable(core->hw);
+
+ trace_clk_disable_complete_rcuidle(core);
+
+ clk_core_disable(core->parent);
+}
+
+static void clk_core_disable_lock(struct clk_core *core)
+{
+ unsigned long flags;
+
+ flags = clk_enable_lock();
+ clk_core_disable(core);
+ clk_enable_unlock(flags);
+}
+
+/**
+ * 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)
+{
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
+ clk_core_disable_lock(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_disable);
+
+static int clk_core_enable(struct clk_core *core)
+{
+ int ret = 0;
+
+ lockdep_assert_held(&enable_lock);
+
+ if (!core)
+ return 0;
+
+ if (WARN(core->prepare_count == 0,
+ "Enabling unprepared %s\n", core->name))
+ return -ESHUTDOWN;
+
+ if (core->enable_count == 0) {
+ ret = clk_core_enable(core->parent);
+
+ if (ret)
+ return ret;
+
+ trace_clk_enable_rcuidle(core);
+
+ if (core->ops->enable)
+ ret = core->ops->enable(core->hw);
+
+ trace_clk_enable_complete_rcuidle(core);
+
+ if (ret) {
+ clk_core_disable(core->parent);
+ return ret;
+ }
+ }
+
+ core->enable_count++;
+ return 0;
+}
+
+static int clk_core_enable_lock(struct clk_core *core)
+{
+ unsigned long flags;
+ int ret;
+
+ flags = clk_enable_lock();
+ ret = clk_core_enable(core);
+ clk_enable_unlock(flags);
+
+ return ret;
+}
+
+/**
+ * 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)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_enable_lock(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_enable);
+
+static int clk_core_prepare_enable(struct clk_core *core)
+{
+ int ret;
+
+ ret = clk_core_prepare_lock(core);
+ if (ret)
+ return ret;
+
+ ret = clk_core_enable_lock(core);
+ if (ret)
+ clk_core_unprepare_lock(core);
+
+ return ret;
+}
+
+static void clk_core_disable_unprepare(struct clk_core *core)
+{
+ clk_core_disable_lock(core);
+ clk_core_unprepare_lock(core);
+}
+
+static void clk_unprepare_unused_subtree(struct clk_core *core)
+{
+ struct clk_core *child;
+
+ lockdep_assert_held(&prepare_lock);
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_unprepare_unused_subtree(child);
+
+ if (core->prepare_count)
+ return;
+
+ if (core->flags & CLK_IGNORE_UNUSED)
+ return;
+
+ if (clk_pm_runtime_get(core))
+ return;
+
+ if (clk_core_is_prepared(core)) {
+ trace_clk_unprepare(core);
+ if (core->ops->unprepare_unused)
+ core->ops->unprepare_unused(core->hw);
+ else if (core->ops->unprepare)
+ core->ops->unprepare(core->hw);
+ trace_clk_unprepare_complete(core);
+ }
+
+ clk_pm_runtime_put(core);
+}
+
+static void clk_disable_unused_subtree(struct clk_core *core)
+{
+ struct clk_core *child;
+ unsigned long flags;
+
+ lockdep_assert_held(&prepare_lock);
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_disable_unused_subtree(child);
+
+ if (core->flags & CLK_OPS_PARENT_ENABLE)
+ clk_core_prepare_enable(core->parent);
+
+ if (clk_pm_runtime_get(core))
+ goto unprepare_out;
+
+ flags = clk_enable_lock();
+
+ if (core->enable_count)
+ goto unlock_out;
+
+ if (core->flags & CLK_IGNORE_UNUSED)
+ goto unlock_out;
+
+ /*
+ * some gate clocks have special needs during the disable-unused
+ * sequence. call .disable_unused if available, otherwise fall
+ * back to .disable
+ */
+ if (clk_core_is_enabled(core)) {
+ trace_clk_disable(core);
+ if (core->ops->disable_unused)
+ core->ops->disable_unused(core->hw);
+ else if (core->ops->disable)
+ core->ops->disable(core->hw);
+ trace_clk_disable_complete(core);
+ }
+
+unlock_out:
+ clk_enable_unlock(flags);
+ clk_pm_runtime_put(core);
+unprepare_out:
+ if (core->flags & CLK_OPS_PARENT_ENABLE)
+ clk_core_disable_unprepare(core->parent);
+}
+
+static bool clk_ignore_unused;
+static int __init clk_ignore_unused_setup(char *__unused)
+{
+ clk_ignore_unused = true;
+ return 1;
+}
+__setup("clk_ignore_unused", clk_ignore_unused_setup);
+
+static int clk_disable_unused(void)
+{
+ struct clk_core *core;
+
+ if (clk_ignore_unused) {
+ pr_warn("clk: Not disabling unused clocks\n");
+ return 0;
+ }
+
+ clk_prepare_lock();
+
+ hlist_for_each_entry(core, &clk_root_list, child_node)
+ clk_disable_unused_subtree(core);
+
+ hlist_for_each_entry(core, &clk_orphan_list, child_node)
+ clk_disable_unused_subtree(core);
+
+ hlist_for_each_entry(core, &clk_root_list, child_node)
+ clk_unprepare_unused_subtree(core);
+
+ hlist_for_each_entry(core, &clk_orphan_list, child_node)
+ clk_unprepare_unused_subtree(core);
+
+ clk_prepare_unlock();
+
+ return 0;
+}
+late_initcall_sync(clk_disable_unused);
+
+static int clk_core_determine_round_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
+{
+ long rate;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ /*
+ * At this point, core protection will be disabled if
+ * - if the provider is not protected at all
+ * - if the calling consumer is the only one which has exclusivity
+ * over the provider
+ */
+ if (clk_core_rate_is_protected(core)) {
+ req->rate = core->rate;
+ } else if (core->ops->determine_rate) {
+ return core->ops->determine_rate(core->hw, req);
+ } else if (core->ops->round_rate) {
+ rate = core->ops->round_rate(core->hw, req->rate,
+ &req->best_parent_rate);
+ if (rate < 0)
+ return rate;
+
+ req->rate = rate;
+ } else {
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void clk_core_init_rate_req(struct clk_core * const core,
+ struct clk_rate_request *req)
+{
+ struct clk_core *parent;
+
+ if (WARN_ON(!core || !req))
+ return;
+
+ parent = core->parent;
+ if (parent) {
+ req->best_parent_hw = parent->hw;
+ req->best_parent_rate = parent->rate;
+ } else {
+ req->best_parent_hw = NULL;
+ req->best_parent_rate = 0;
+ }
+}
+
+static bool clk_core_can_round(struct clk_core * const core)
+{
+ if (core->ops->determine_rate || core->ops->round_rate)
+ return true;
+
+ return false;
+}
+
+static int clk_core_round_rate_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
+{
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core) {
+ req->rate = 0;
+ return 0;
+ }
+
+ clk_core_init_rate_req(core, req);
+
+ if (clk_core_can_round(core))
+ return clk_core_determine_round_nolock(core, req);
+ else if (core->flags & CLK_SET_RATE_PARENT)
+ return clk_core_round_rate_nolock(core->parent, req);
+
+ req->rate = core->rate;
+ return 0;
+}
+
+/**
+ * __clk_determine_rate - get the closest rate actually supported by a clock
+ * @hw: determine the rate of this clock
+ * @req: target rate request
+ *
+ * Useful for clk_ops such as .set_rate and .determine_rate.
+ */
+int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ if (!hw) {
+ req->rate = 0;
+ return 0;
+ }
+
+ return clk_core_round_rate_nolock(hw->core, req);
+}
+EXPORT_SYMBOL_GPL(__clk_determine_rate);
+
+unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate)
+{
+ int ret;
+ struct clk_rate_request req;
+
+ clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
+
+ ret = clk_core_round_rate_nolock(hw->core, &req);
+ if (ret)
+ return 0;
+
+ return req.rate;
+}
+EXPORT_SYMBOL_GPL(clk_hw_round_rate);
+
+/**
+ * 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)
+{
+ struct clk_rate_request req;
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
+
+ ret = clk_core_round_rate_nolock(clk->core, &req);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ if (ret)
+ return ret;
+
+ return req.rate;
+}
+EXPORT_SYMBOL_GPL(clk_round_rate);
+
+/**
+ * __clk_notify - call clk notifier chain
+ * @core: 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_core *core, 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.old_rate = old_rate;
+ cnd.new_rate = new_rate;
+
+ list_for_each_entry(cn, &clk_notifier_list, node) {
+ if (cn->clk->core == core) {
+ cnd.clk = cn->clk;
+ ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
+ &cnd);
+ if (ret & NOTIFY_STOP_MASK)
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+/**
+ * __clk_recalc_accuracies
+ * @core: first clk in the subtree
+ *
+ * Walks the subtree of clks starting with clk and recalculates accuracies as
+ * it goes. Note that if a clk does not implement the .recalc_accuracy
+ * callback then it is assumed that the clock will take on the accuracy of its
+ * parent.
+ */
+static void __clk_recalc_accuracies(struct clk_core *core)
+{
+ unsigned long parent_accuracy = 0;
+ struct clk_core *child;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (core->parent)
+ parent_accuracy = core->parent->accuracy;
+
+ if (core->ops->recalc_accuracy)
+ core->accuracy = core->ops->recalc_accuracy(core->hw,
+ parent_accuracy);
+ else
+ core->accuracy = parent_accuracy;
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ __clk_recalc_accuracies(child);
+}
+
+static long clk_core_get_accuracy(struct clk_core *core)
+{
+ unsigned long accuracy;
+
+ clk_prepare_lock();
+ if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE))
+ __clk_recalc_accuracies(core);
+
+ accuracy = __clk_get_accuracy(core);
+ clk_prepare_unlock();
+
+ return accuracy;
+}
+
+/**
+ * clk_get_accuracy - return the accuracy of clk
+ * @clk: the clk whose accuracy is being returned
+ *
+ * Simply returns the cached accuracy of the clk, unless
+ * CLK_GET_ACCURACY_NOCACHE flag is set, which means a recalc_rate will be
+ * issued.
+ * If clk is NULL then returns 0.
+ */
+long clk_get_accuracy(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_accuracy(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_accuracy);
+
+static unsigned long clk_recalc(struct clk_core *core,
+ unsigned long parent_rate)
+{
+ unsigned long rate = parent_rate;
+
+ if (core->ops->recalc_rate && !clk_pm_runtime_get(core)) {
+ rate = core->ops->recalc_rate(core->hw, parent_rate);
+ clk_pm_runtime_put(core);
+ }
+ return rate;
+}
+
+/**
+ * __clk_recalc_rates
+ * @core: 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 its parent.
+ *
+ * clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
+ * if necessary.
+ */
+static void __clk_recalc_rates(struct clk_core *core, unsigned long msg)
+{
+ unsigned long old_rate;
+ unsigned long parent_rate = 0;
+ struct clk_core *child;
+
+ lockdep_assert_held(&prepare_lock);
+
+ old_rate = core->rate;
+
+ if (core->parent)
+ parent_rate = core->parent->rate;
+
+ core->rate = clk_recalc(core, parent_rate);
+
+ /*
+ * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
+ * & ABORT_RATE_CHANGE notifiers
+ */
+ if (core->notifier_count && msg)
+ __clk_notify(core, msg, old_rate, core->rate);
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ __clk_recalc_rates(child, msg);
+}
+
+static unsigned long clk_core_get_rate(struct clk_core *core)
+{
+ unsigned long rate;
+
+ clk_prepare_lock();
+
+ if (core && (core->flags & CLK_GET_RATE_NOCACHE))
+ __clk_recalc_rates(core, 0);
+
+ rate = clk_core_get_rate_nolock(core);
+ clk_prepare_unlock();
+
+ return rate;
+}
+
+/**
+ * clk_get_rate - return the rate of clk
+ * @clk: the clk whose rate is being returned
+ *
+ * Simply returns the cached rate of the clk, unless CLK_GET_RATE_NOCACHE flag
+ * is set, which means a recalc_rate will be issued.
+ * If clk is NULL then returns 0.
+ */
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_rate(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_rate);
+
+static int clk_fetch_parent_index(struct clk_core *core,
+ struct clk_core *parent)
+{
+ int i;
+
+ if (!parent)
+ return -EINVAL;
+
+ for (i = 0; i < core->num_parents; i++)
+ if (clk_core_get_parent_by_index(core, i) == parent)
+ return i;
+
+ return -EINVAL;
+}
+
+/*
+ * Update the orphan status of @core and all its children.
+ */
+static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan)
+{
+ struct clk_core *child;
+
+ core->orphan = is_orphan;
+
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_core_update_orphan_status(child, is_orphan);
+}
+
+static void clk_reparent(struct clk_core *core, struct clk_core *new_parent)
+{
+ bool was_orphan = core->orphan;
+
+ hlist_del(&core->child_node);
+
+ if (new_parent) {
+ bool becomes_orphan = new_parent->orphan;
+
+ /* avoid duplicate POST_RATE_CHANGE notifications */
+ if (new_parent->new_child == core)
+ new_parent->new_child = NULL;
+
+ hlist_add_head(&core->child_node, &new_parent->children);
+
+ if (was_orphan != becomes_orphan)
+ clk_core_update_orphan_status(core, becomes_orphan);
+ } else {
+ hlist_add_head(&core->child_node, &clk_orphan_list);
+ if (!was_orphan)
+ clk_core_update_orphan_status(core, true);
+ }
+
+ core->parent = new_parent;
+}
+
+static struct clk_core *__clk_set_parent_before(struct clk_core *core,
+ struct clk_core *parent)
+{
+ unsigned long flags;
+ struct clk_core *old_parent = core->parent;
+
+ /*
+ * 1. enable parents for CLK_OPS_PARENT_ENABLE clock
+ *
+ * 2. Migrate prepare state between parents and prevent race with
+ * clk_enable().
+ *
+ * If the clock is not prepared, then a race with
+ * clk_enable/disable() is impossible since we already have the
+ * prepare lock (future calls to clk_enable() need to be preceded by
+ * a clk_prepare()).
+ *
+ * If the clock is prepared, migrate the prepared state to the new
+ * parent and also protect against a race with clk_enable() by
+ * forcing the clock and the new parent on. This ensures that all
+ * future calls to clk_enable() are practically NOPs with respect to
+ * hardware and software states.
+ *
+ * See also: Comment for clk_set_parent() below.
+ */
+
+ /* enable old_parent & parent if CLK_OPS_PARENT_ENABLE is set */
+ if (core->flags & CLK_OPS_PARENT_ENABLE) {
+ clk_core_prepare_enable(old_parent);
+ clk_core_prepare_enable(parent);
+ }
+
+ /* migrate prepare count if > 0 */
+ if (core->prepare_count) {
+ clk_core_prepare_enable(parent);
+ clk_core_enable_lock(core);
+ }
+
+ /* update the clk tree topology */
+ flags = clk_enable_lock();
+ clk_reparent(core, parent);
+ clk_enable_unlock(flags);
+
+ return old_parent;
+}
+
+static void __clk_set_parent_after(struct clk_core *core,
+ struct clk_core *parent,
+ struct clk_core *old_parent)
+{
+ /*
+ * Finish the migration of prepare state and undo the changes done
+ * for preventing a race with clk_enable().
+ */
+ if (core->prepare_count) {
+ clk_core_disable_lock(core);
+ clk_core_disable_unprepare(old_parent);
+ }
+
+ /* re-balance ref counting if CLK_OPS_PARENT_ENABLE is set */
+ if (core->flags & CLK_OPS_PARENT_ENABLE) {
+ clk_core_disable_unprepare(parent);
+ clk_core_disable_unprepare(old_parent);
+ }
+}
+
+static int __clk_set_parent(struct clk_core *core, struct clk_core *parent,
+ u8 p_index)
+{
+ unsigned long flags;
+ int ret = 0;
+ struct clk_core *old_parent;
+
+ old_parent = __clk_set_parent_before(core, parent);
+
+ trace_clk_set_parent(core, parent);
+
+ /* change clock input source */
+ if (parent && core->ops->set_parent)
+ ret = core->ops->set_parent(core->hw, p_index);
+
+ trace_clk_set_parent_complete(core, parent);
+
+ if (ret) {
+ flags = clk_enable_lock();
+ clk_reparent(core, old_parent);
+ clk_enable_unlock(flags);
+ __clk_set_parent_after(core, old_parent, parent);
+
+ return ret;
+ }
+
+ __clk_set_parent_after(core, parent, old_parent);
+
+ return 0;
+}
+
+/**
+ * __clk_speculate_rates
+ * @core: 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 its parent.
+ */
+static int __clk_speculate_rates(struct clk_core *core,
+ unsigned long parent_rate)
+{
+ struct clk_core *child;
+ unsigned long new_rate;
+ int ret = NOTIFY_DONE;
+
+ lockdep_assert_held(&prepare_lock);
+
+ new_rate = clk_recalc(core, parent_rate);
+
+ /* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */
+ if (core->notifier_count)
+ ret = __clk_notify(core, PRE_RATE_CHANGE, core->rate, new_rate);
+
+ if (ret & NOTIFY_STOP_MASK) {
+ pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n",
+ __func__, core->name, ret);
+ goto out;
+ }
+
+ hlist_for_each_entry(child, &core->children, child_node) {
+ ret = __clk_speculate_rates(child, new_rate);
+ if (ret & NOTIFY_STOP_MASK)
+ break;
+ }
+
+out:
+ return ret;
+}
+
+static void clk_calc_subtree(struct clk_core *core, unsigned long new_rate,
+ struct clk_core *new_parent, u8 p_index)
+{
+ struct clk_core *child;
+
+ core->new_rate = new_rate;
+ core->new_parent = new_parent;
+ core->new_parent_index = p_index;
+ /* include clk in new parent's PRE_RATE_CHANGE notifications */
+ core->new_child = NULL;
+ if (new_parent && new_parent != core->parent)
+ new_parent->new_child = core;
+
+ hlist_for_each_entry(child, &core->children, child_node) {
+ child->new_rate = clk_recalc(child, new_rate);
+ clk_calc_subtree(child, child->new_rate, NULL, 0);
+ }
+}
+
+/*
+ * calculate the new rates returning the topmost clock that has to be
+ * changed.
+ */
+static struct clk_core *clk_calc_new_rates(struct clk_core *core,
+ unsigned long rate)
+{
+ struct clk_core *top = core;
+ struct clk_core *old_parent, *parent;
+ unsigned long best_parent_rate = 0;
+ unsigned long new_rate;
+ unsigned long min_rate;
+ unsigned long max_rate;
+ int p_index = 0;
+ long ret;
+
+ /* sanity */
+ if (IS_ERR_OR_NULL(core))
+ return NULL;
+
+ /* save parent rate, if it exists */
+ parent = old_parent = core->parent;
+ if (parent)
+ best_parent_rate = parent->rate;
+
+ clk_core_get_boundaries(core, &min_rate, &max_rate);
+
+ /* find the closest rate and parent clk/rate */
+ if (clk_core_can_round(core)) {
+ struct clk_rate_request req;
+
+ req.rate = rate;
+ req.min_rate = min_rate;
+ req.max_rate = max_rate;
+
+ clk_core_init_rate_req(core, &req);
+
+ ret = clk_core_determine_round_nolock(core, &req);
+ if (ret < 0)
+ return NULL;
+
+ best_parent_rate = req.best_parent_rate;
+ new_rate = req.rate;
+ parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
+
+ if (new_rate < min_rate || new_rate > max_rate)
+ return NULL;
+ } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) {
+ /* pass-through clock without adjustable parent */
+ core->new_rate = core->rate;
+ return NULL;
+ } else {
+ /* pass-through clock with adjustable parent */
+ top = clk_calc_new_rates(parent, rate);
+ new_rate = parent->new_rate;
+ goto out;
+ }
+
+ /* some clocks must be gated to change parent */
+ if (parent != old_parent &&
+ (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
+ pr_debug("%s: %s not gated but wants to reparent\n",
+ __func__, core->name);
+ return NULL;
+ }
+
+ /* try finding the new parent index */
+ if (parent && core->num_parents > 1) {
+ p_index = clk_fetch_parent_index(core, parent);
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, core->name);
+ return NULL;
+ }
+ }
+
+ if ((core->flags & CLK_SET_RATE_PARENT) && parent &&
+ best_parent_rate != parent->rate)
+ top = clk_calc_new_rates(parent, best_parent_rate);
+
+out:
+ clk_calc_subtree(core, new_rate, parent, p_index);
+
+ 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_core *clk_propagate_rate_change(struct clk_core *core,
+ unsigned long event)
+{
+ struct clk_core *child, *tmp_clk, *fail_clk = NULL;
+ int ret = NOTIFY_DONE;
+
+ if (core->rate == core->new_rate)
+ return NULL;
+
+ if (core->notifier_count) {
+ ret = __clk_notify(core, event, core->rate, core->new_rate);
+ if (ret & NOTIFY_STOP_MASK)
+ fail_clk = core;
+ }
+
+ hlist_for_each_entry(child, &core->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != core)
+ continue;
+ tmp_clk = clk_propagate_rate_change(child, event);
+ if (tmp_clk)
+ fail_clk = tmp_clk;
+ }
+
+ /* handle the new child who might not be in core->children yet */
+ if (core->new_child) {
+ tmp_clk = clk_propagate_rate_change(core->new_child, event);
+ if (tmp_clk)
+ fail_clk = tmp_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_core *core)
+{
+ struct clk_core *child;
+ struct hlist_node *tmp;
+ unsigned long old_rate;
+ unsigned long best_parent_rate = 0;
+ bool skip_set_rate = false;
+ struct clk_core *old_parent;
+ struct clk_core *parent = NULL;
+
+ old_rate = core->rate;
+
+ if (core->new_parent) {
+ parent = core->new_parent;
+ best_parent_rate = core->new_parent->rate;
+ } else if (core->parent) {
+ parent = core->parent;
+ best_parent_rate = core->parent->rate;
+ }
+
+ if (clk_pm_runtime_get(core))
+ return;
+
+ if (core->flags & CLK_SET_RATE_UNGATE) {
+ unsigned long flags;
+
+ clk_core_prepare(core);
+ flags = clk_enable_lock();
+ clk_core_enable(core);
+ clk_enable_unlock(flags);
+ }
+
+ if (core->new_parent && core->new_parent != core->parent) {
+ old_parent = __clk_set_parent_before(core, core->new_parent);
+ trace_clk_set_parent(core, core->new_parent);
+
+ if (core->ops->set_rate_and_parent) {
+ skip_set_rate = true;
+ core->ops->set_rate_and_parent(core->hw, core->new_rate,
+ best_parent_rate,
+ core->new_parent_index);
+ } else if (core->ops->set_parent) {
+ core->ops->set_parent(core->hw, core->new_parent_index);
+ }
+
+ trace_clk_set_parent_complete(core, core->new_parent);
+ __clk_set_parent_after(core, core->new_parent, old_parent);
+ }
+
+ if (core->flags & CLK_OPS_PARENT_ENABLE)
+ clk_core_prepare_enable(parent);
+
+ trace_clk_set_rate(core, core->new_rate);
+
+ if (!skip_set_rate && core->ops->set_rate)
+ core->ops->set_rate(core->hw, core->new_rate, best_parent_rate);
+
+ trace_clk_set_rate_complete(core, core->new_rate);
+
+ core->rate = clk_recalc(core, best_parent_rate);
+
+ if (core->flags & CLK_SET_RATE_UNGATE) {
+ unsigned long flags;
+
+ flags = clk_enable_lock();
+ clk_core_disable(core);
+ clk_enable_unlock(flags);
+ clk_core_unprepare(core);
+ }
+
+ if (core->flags & CLK_OPS_PARENT_ENABLE)
+ clk_core_disable_unprepare(parent);
+
+ if (core->notifier_count && old_rate != core->rate)
+ __clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate);
+
+ if (core->flags & CLK_RECALC_NEW_RATES)
+ (void)clk_calc_new_rates(core, core->new_rate);
+
+ /*
+ * Use safe iteration, as change_rate can actually swap parents
+ * for certain clock types.
+ */
+ hlist_for_each_entry_safe(child, tmp, &core->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != core)
+ continue;
+ clk_change_rate(child);
+ }
+
+ /* handle the new child who might not be in core->children yet */
+ if (core->new_child)
+ clk_change_rate(core->new_child);
+
+ clk_pm_runtime_put(core);
+}
+
+static unsigned long clk_core_req_round_rate_nolock(struct clk_core *core,
+ unsigned long req_rate)
+{
+ int ret, cnt;
+ struct clk_rate_request req;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ /* simulate what the rate would be if it could be freely set */
+ cnt = clk_core_rate_nuke_protect(core);
+ if (cnt < 0)
+ return cnt;
+
+ clk_core_get_boundaries(core, &req.min_rate, &req.max_rate);
+ req.rate = req_rate;
+
+ ret = clk_core_round_rate_nolock(core, &req);
+
+ /* restore the protection */
+ clk_core_rate_restore_protect(core, cnt);
+
+ return ret ? 0 : req.rate;
+}
+
+static int clk_core_set_rate_nolock(struct clk_core *core,
+ unsigned long req_rate)
+{
+ struct clk_core *top, *fail_clk;
+ unsigned long rate;
+ int ret = 0;
+
+ if (!core)
+ return 0;
+
+ rate = clk_core_req_round_rate_nolock(core, req_rate);
+
+ /* bail early if nothing to do */
+ if (rate == clk_core_get_rate_nolock(core))
+ return 0;
+
+ /* fail on a direct rate set of a protected provider */
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ /* calculate new rates and get the topmost changed clock */
+ top = clk_calc_new_rates(core, req_rate);
+ if (!top)
+ return -EINVAL;
+
+ ret = clk_pm_runtime_get(core);
+ if (ret)
+ return ret;
+
+ /* notify that we are about to change rates */
+ fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
+ if (fail_clk) {
+ pr_debug("%s: failed to set %s rate\n", __func__,
+ fail_clk->name);
+ clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
+ ret = -EBUSY;
+ goto err;
+ }
+
+ /* change the rates */
+ clk_change_rate(top);
+
+ core->req_rate = req_rate;
+err:
+ clk_pm_runtime_put(core);
+
+ return ret;
+}
+
+/**
+ * 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 adjust the rate of clk.
+ *
+ * Setting the CLK_SET_RATE_PARENT flag allows the rate change operation to
+ * 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 unchanged
+ * 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 its 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.
+ *
+ * Rate changes are accomplished via tree traversal that also recalculates the
+ * rates for the clocks and fires off POST_RATE_CHANGE notifiers.
+ *
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ /* prevent racing with updates to the clock topology */
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate);
+
+/**
+ * clk_set_rate_exclusive - specify a new rate get exclusive control
+ * @clk: the clk whose rate is being changed
+ * @rate: the new rate for clk
+ *
+ * This is a combination of clk_set_rate() and clk_rate_exclusive_get()
+ * within a critical section
+ *
+ * This can be used initially to ensure that at least 1 consumer is
+ * statisfied when several consumers are competing for exclusivity over the
+ * same clock provider.
+ *
+ * The exclusivity is not applied if setting the rate failed.
+ *
+ * Calls to clk_rate_exclusive_get() should be balanced with calls to
+ * clk_rate_exclusive_put().
+ *
+ * Returns 0 on success, -EERROR otherwise.
+ */
+int clk_set_rate_exclusive(struct clk *clk, unsigned long rate)
+{
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ /* prevent racing with updates to the clock topology */
+ clk_prepare_lock();
+
+ /*
+ * The temporary protection removal is not here, on purpose
+ * This function is meant to be used instead of clk_rate_protect,
+ * so before the consumer code path protect the clock provider
+ */
+
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (!ret) {
+ clk_core_rate_protect(clk->core);
+ clk->exclusive_count++;
+ }
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate_exclusive);
+
+/**
+ * clk_set_rate_range - set a rate range for a clock source
+ * @clk: clock source
+ * @min: desired minimum clock rate in Hz, inclusive
+ * @max: desired maximum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
+{
+ int ret = 0;
+ unsigned long old_min, old_max, rate;
+
+ if (!clk)
+ return 0;
+
+ if (min > max) {
+ pr_err("%s: clk %s dev %s con %s: invalid range [%lu, %lu]\n",
+ __func__, clk->core->name, clk->dev_id, clk->con_id,
+ min, max);
+ return -EINVAL;
+ }
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ /* Save the current values in case we need to rollback the change */
+ old_min = clk->min_rate;
+ old_max = clk->max_rate;
+ clk->min_rate = min;
+ clk->max_rate = max;
+
+ rate = clk_core_get_rate_nolock(clk->core);
+ if (rate < min || rate > max) {
+ /*
+ * FIXME:
+ * We are in bit of trouble here, current rate is outside the
+ * the requested range. We are going try to request appropriate
+ * range boundary but there is a catch. It may fail for the
+ * usual reason (clock broken, clock protected, etc) but also
+ * because:
+ * - round_rate() was not favorable and fell on the wrong
+ * side of the boundary
+ * - the determine_rate() callback does not really check for
+ * this corner case when determining the rate
+ */
+
+ if (rate < min)
+ rate = min;
+ else
+ rate = max;
+
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (ret) {
+ /* rollback the changes */
+ clk->min_rate = old_min;
+ clk->max_rate = old_max;
+ }
+ }
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_rate_range);
+
+/**
+ * clk_set_min_rate - set a minimum clock rate for a clock source
+ * @clk: clock source
+ * @rate: desired minimum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_min_rate(struct clk *clk, unsigned long rate)
+{
+ if (!clk)
+ return 0;
+
+ return clk_set_rate_range(clk, rate, clk->max_rate);
+}
+EXPORT_SYMBOL_GPL(clk_set_min_rate);
+
+/**
+ * clk_set_max_rate - set a maximum clock rate for a clock source
+ * @clk: clock source
+ * @rate: desired maximum clock rate in Hz, inclusive
+ *
+ * Returns success (0) or negative errno.
+ */
+int clk_set_max_rate(struct clk *clk, unsigned long rate)
+{
+ if (!clk)
+ return 0;
+
+ return clk_set_rate_range(clk, clk->min_rate, rate);
+}
+EXPORT_SYMBOL_GPL(clk_set_max_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;
+
+ if (!clk)
+ return NULL;
+
+ clk_prepare_lock();
+ /* TODO: Create a per-user clk and change callers to call clk_put */
+ parent = !clk->core->parent ? NULL : clk->core->parent->hw->clk;
+ clk_prepare_unlock();
+
+ return parent;
+}
+EXPORT_SYMBOL_GPL(clk_get_parent);
+
+static struct clk_core *__clk_init_parent(struct clk_core *core)
+{
+ u8 index = 0;
+
+ if (core->num_parents > 1 && core->ops->get_parent)
+ index = core->ops->get_parent(core->hw);
+
+ return clk_core_get_parent_by_index(core, index);
+}
+
+static void clk_core_reparent(struct clk_core *core,
+ struct clk_core *new_parent)
+{
+ clk_reparent(core, new_parent);
+ __clk_recalc_accuracies(core);
+ __clk_recalc_rates(core, POST_RATE_CHANGE);
+}
+
+void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
+{
+ if (!hw)
+ return;
+
+ clk_core_reparent(hw->core, !new_parent ? NULL : new_parent->core);
+}
+
+/**
+ * clk_has_parent - check if a clock is a possible parent for another
+ * @clk: clock source
+ * @parent: parent clock source
+ *
+ * This function can be used in drivers that need to check that a clock can be
+ * the parent of another without actually changing the parent.
+ *
+ * Returns true if @parent is a possible parent for @clk, false otherwise.
+ */
+bool clk_has_parent(struct clk *clk, struct clk *parent)
+{
+ struct clk_core *core, *parent_core;
+
+ /* NULL clocks should be nops, so return success if either is NULL. */
+ if (!clk || !parent)
+ return true;
+
+ core = clk->core;
+ parent_core = parent->core;
+
+ /* Optimize for the case where the parent is already the parent. */
+ if (core->parent == parent_core)
+ return true;
+
+ return match_string(core->parent_names, core->num_parents,
+ parent_core->name) >= 0;
+}
+EXPORT_SYMBOL_GPL(clk_has_parent);
+
+static int clk_core_set_parent_nolock(struct clk_core *core,
+ struct clk_core *parent)
+{
+ int ret = 0;
+ int p_index = 0;
+ unsigned long p_rate = 0;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ if (core->parent == parent)
+ return 0;
+
+ /* verify ops for for multi-parent clks */
+ if (core->num_parents > 1 && !core->ops->set_parent)
+ return -EPERM;
+
+ /* check that we are allowed to re-parent if the clock is in use */
+ if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count)
+ return -EBUSY;
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ /* try finding the new parent index */
+ if (parent) {
+ p_index = clk_fetch_parent_index(core, parent);
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, core->name);
+ return p_index;
+ }
+ p_rate = parent->rate;
+ }
+
+ ret = clk_pm_runtime_get(core);
+ if (ret)
+ return ret;
+
+ /* propagate PRE_RATE_CHANGE notifications */
+ ret = __clk_speculate_rates(core, p_rate);
+
+ /* abort if a driver objects */
+ if (ret & NOTIFY_STOP_MASK)
+ goto runtime_put;
+
+ /* do the re-parent */
+ ret = __clk_set_parent(core, parent, p_index);
+
+ /* propagate rate an accuracy recalculation accordingly */
+ if (ret) {
+ __clk_recalc_rates(core, ABORT_RATE_CHANGE);
+ } else {
+ __clk_recalc_rates(core, POST_RATE_CHANGE);
+ __clk_recalc_accuracies(core);
+ }
+
+runtime_put:
+ clk_pm_runtime_put(core);
+
+ 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 its new input source. If clk is in
+ * prepared state, the clk will get enabled for the duration of this call. If
+ * that's not acceptable for a specific clk (Eg: the consumer can't handle
+ * that, the reparenting is glitchy in hardware, etc), use the
+ * CLK_SET_PARENT_GATE flag to allow reparenting only when clk is unprepared.
+ *
+ * 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;
+
+ if (!clk)
+ return 0;
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_parent_nolock(clk->core,
+ parent ? parent->core : NULL);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_parent);
+
+static int clk_core_set_phase_nolock(struct clk_core *core, int degrees)
+{
+ int ret = -EINVAL;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (!core)
+ return 0;
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ trace_clk_set_phase(core, degrees);
+
+ if (core->ops->set_phase) {
+ ret = core->ops->set_phase(core->hw, degrees);
+ if (!ret)
+ core->phase = degrees;
+ }
+
+ trace_clk_set_phase_complete(core, degrees);
+
+ return ret;
+}
+
+/**
+ * clk_set_phase - adjust the phase shift of a clock signal
+ * @clk: clock signal source
+ * @degrees: number of degrees the signal is shifted
+ *
+ * Shifts the phase of a clock signal by the specified
+ * degrees. Returns 0 on success, -EERROR otherwise.
+ *
+ * This function makes no distinction about the input or reference
+ * signal that we adjust the clock signal phase against. For example
+ * phase locked-loop clock signal generators we may shift phase with
+ * respect to feedback clock signal input, but for other cases the
+ * clock phase may be shifted with respect to some other, unspecified
+ * signal.
+ *
+ * Additionally the concept of phase shift does not propagate through
+ * the clock tree hierarchy, which sets it apart from clock rates and
+ * clock accuracy. A parent clock phase attribute does not have an
+ * impact on the phase attribute of a child clock.
+ */
+int clk_set_phase(struct clk *clk, int degrees)
+{
+ int ret;
+
+ if (!clk)
+ return 0;
+
+ /* sanity check degrees */
+ degrees %= 360;
+ if (degrees < 0)
+ degrees += 360;
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_phase_nolock(clk->core, degrees);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_phase);
+
+static int clk_core_get_phase(struct clk_core *core)
+{
+ int ret;
+
+ clk_prepare_lock();
+ /* Always try to update cached phase if possible */
+ if (core->ops->get_phase)
+ core->phase = core->ops->get_phase(core->hw);
+ ret = core->phase;
+ clk_prepare_unlock();
+
+ return ret;
+}
+
+/**
+ * clk_get_phase - return the phase shift of a clock signal
+ * @clk: clock signal source
+ *
+ * Returns the phase shift of a clock node in degrees, otherwise returns
+ * -EERROR.
+ */
+int clk_get_phase(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_phase(clk->core);
+}
+EXPORT_SYMBOL_GPL(clk_get_phase);
+
+static void clk_core_reset_duty_cycle_nolock(struct clk_core *core)
+{
+ /* Assume a default value of 50% */
+ core->duty.num = 1;
+ core->duty.den = 2;
+}
+
+static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core);
+
+static int clk_core_update_duty_cycle_nolock(struct clk_core *core)
+{
+ struct clk_duty *duty = &core->duty;
+ int ret = 0;
+
+ if (!core->ops->get_duty_cycle)
+ return clk_core_update_duty_cycle_parent_nolock(core);
+
+ ret = core->ops->get_duty_cycle(core->hw, duty);
+ if (ret)
+ goto reset;
+
+ /* Don't trust the clock provider too much */
+ if (duty->den == 0 || duty->num > duty->den) {
+ ret = -EINVAL;
+ goto reset;
+ }
+
+ return 0;
+
+reset:
+ clk_core_reset_duty_cycle_nolock(core);
+ return ret;
+}
+
+static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core)
+{
+ int ret = 0;
+
+ if (core->parent &&
+ core->flags & CLK_DUTY_CYCLE_PARENT) {
+ ret = clk_core_update_duty_cycle_nolock(core->parent);
+ memcpy(&core->duty, &core->parent->duty, sizeof(core->duty));
+ } else {
+ clk_core_reset_duty_cycle_nolock(core);
+ }
+
+ return ret;
+}
+
+static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core,
+ struct clk_duty *duty);
+
+static int clk_core_set_duty_cycle_nolock(struct clk_core *core,
+ struct clk_duty *duty)
+{
+ int ret;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ trace_clk_set_duty_cycle(core, duty);
+
+ if (!core->ops->set_duty_cycle)
+ return clk_core_set_duty_cycle_parent_nolock(core, duty);
+
+ ret = core->ops->set_duty_cycle(core->hw, duty);
+ if (!ret)
+ memcpy(&core->duty, duty, sizeof(*duty));
+
+ trace_clk_set_duty_cycle_complete(core, duty);
+
+ return ret;
+}
+
+static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core,
+ struct clk_duty *duty)
+{
+ int ret = 0;
+
+ if (core->parent &&
+ core->flags & (CLK_DUTY_CYCLE_PARENT | CLK_SET_RATE_PARENT)) {
+ ret = clk_core_set_duty_cycle_nolock(core->parent, duty);
+ memcpy(&core->duty, &core->parent->duty, sizeof(core->duty));
+ }
+
+ return ret;
+}
+
+/**
+ * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @num: numerator of the duty cycle ratio to be applied
+ * @den: denominator of the duty cycle ratio to be applied
+ *
+ * Apply the duty cycle ratio if the ratio is valid and the clock can
+ * perform this operation
+ *
+ * Returns (0) on success, a negative errno otherwise.
+ */
+int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den)
+{
+ int ret;
+ struct clk_duty duty;
+
+ if (!clk)
+ return 0;
+
+ /* sanity check the ratio */
+ if (den == 0 || num > den)
+ return -EINVAL;
+
+ duty.num = num;
+ duty.den = den;
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_duty_cycle_nolock(clk->core, &duty);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_duty_cycle);
+
+static int clk_core_get_scaled_duty_cycle(struct clk_core *core,
+ unsigned int scale)
+{
+ struct clk_duty *duty = &core->duty;
+ int ret;
+
+ clk_prepare_lock();
+
+ ret = clk_core_update_duty_cycle_nolock(core);
+ if (!ret)
+ ret = mult_frac(scale, duty->num, duty->den);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+
+/**
+ * clk_get_scaled_duty_cycle - return the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @scale: scaling factor to be applied to represent the ratio as an integer
+ *
+ * Returns the duty cycle ratio of a clock node multiplied by the provided
+ * scaling factor, or negative errno on error.
+ */
+int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_scaled_duty_cycle(clk->core, scale);
+}
+EXPORT_SYMBOL_GPL(clk_get_scaled_duty_cycle);
+
+/**
+ * clk_is_match - check if two clk's point to the same hardware clock
+ * @p: clk compared against q
+ * @q: clk compared against p
+ *
+ * Returns true if the two struct clk pointers both point to the same hardware
+ * clock node. Put differently, returns true if struct clk *p and struct clk *q
+ * share the same struct clk_core object.
+ *
+ * Returns false otherwise. Note that two NULL clks are treated as matching.
+ */
+bool clk_is_match(const struct clk *p, const struct clk *q)
+{
+ /* trivial case: identical struct clk's or both NULL */
+ if (p == q)
+ return true;
+
+ /* true if clk->core pointers match. Avoid dereferencing garbage */
+ if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
+ if (p->core == q->core)
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(clk_is_match);
+
+/*** debugfs support ***/
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static struct dentry *rootdir;
+static int inited = 0;
+static DEFINE_MUTEX(clk_debug_lock);
+static HLIST_HEAD(clk_debug_list);
+
+static struct hlist_head *all_lists[] = {
+ &clk_root_list,
+ &clk_orphan_list,
+ NULL,
+};
+
+static struct hlist_head *orphan_list[] = {
+ &clk_orphan_list,
+ NULL,
+};
+
+static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ if (!c)
+ return;
+
+ seq_printf(s, "%*s%-*s %7d %8d %8d %11lu %10lu %5d %6d\n",
+ level * 3 + 1, "",
+ 30 - level * 3, c->name,
+ c->enable_count, c->prepare_count, c->protect_count,
+ clk_core_get_rate(c), clk_core_get_accuracy(c),
+ clk_core_get_phase(c),
+ clk_core_get_scaled_duty_cycle(c, 100000));
+}
+
+static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ struct clk_core *child;
+
+ if (!c)
+ return;
+
+ clk_summary_show_one(s, c, level);
+
+ hlist_for_each_entry(child, &c->children, child_node)
+ clk_summary_show_subtree(s, child, level + 1);
+}
+
+static int clk_summary_show(struct seq_file *s, void *data)
+{
+ struct clk_core *c;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
+
+ seq_puts(s, " enable prepare protect duty\n");
+ seq_puts(s, " clock count count count rate accuracy phase cycle\n");
+ seq_puts(s, "---------------------------------------------------------------------------------------------\n");
+
+ clk_prepare_lock();
+
+ for (; *lists; lists++)
+ hlist_for_each_entry(c, *lists, child_node)
+ clk_summary_show_subtree(s, c, 0);
+
+ clk_prepare_unlock();
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_summary);
+
+static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
+{
+ if (!c)
+ return;
+
+ /* This should be JSON format, i.e. elements separated with a comma */
+ seq_printf(s, "\"%s\": { ", c->name);
+ seq_printf(s, "\"enable_count\": %d,", c->enable_count);
+ seq_printf(s, "\"prepare_count\": %d,", c->prepare_count);
+ seq_printf(s, "\"protect_count\": %d,", c->protect_count);
+ seq_printf(s, "\"rate\": %lu,", clk_core_get_rate(c));
+ seq_printf(s, "\"accuracy\": %lu,", clk_core_get_accuracy(c));
+ seq_printf(s, "\"phase\": %d", clk_core_get_phase(c));
+ seq_printf(s, "\"duty_cycle\": %u",
+ clk_core_get_scaled_duty_cycle(c, 100000));
+}
+
+static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
+{
+ struct clk_core *child;
+
+ if (!c)
+ return;
+
+ clk_dump_one(s, c, level);
+
+ hlist_for_each_entry(child, &c->children, child_node) {
+ seq_putc(s, ',');
+ clk_dump_subtree(s, child, level + 1);
+ }
+
+ seq_putc(s, '}');
+}
+
+static int clk_dump_show(struct seq_file *s, void *data)
+{
+ struct clk_core *c;
+ bool first_node = true;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
+
+ seq_putc(s, '{');
+ clk_prepare_lock();
+
+ for (; *lists; lists++) {
+ hlist_for_each_entry(c, *lists, child_node) {
+ if (!first_node)
+ seq_putc(s, ',');
+ first_node = false;
+ clk_dump_subtree(s, c, 0);
+ }
+ }
+
+ clk_prepare_unlock();
+
+ seq_puts(s, "}\n");
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_dump);
+
+static const struct {
+ unsigned long flag;
+ const char *name;
+} clk_flags[] = {
+#define ENTRY(f) { f, #f }
+ ENTRY(CLK_SET_RATE_GATE),
+ ENTRY(CLK_SET_PARENT_GATE),
+ ENTRY(CLK_SET_RATE_PARENT),
+ ENTRY(CLK_IGNORE_UNUSED),
+ ENTRY(CLK_IS_BASIC),
+ ENTRY(CLK_GET_RATE_NOCACHE),
+ ENTRY(CLK_SET_RATE_NO_REPARENT),
+ ENTRY(CLK_GET_ACCURACY_NOCACHE),
+ ENTRY(CLK_RECALC_NEW_RATES),
+ ENTRY(CLK_SET_RATE_UNGATE),
+ ENTRY(CLK_IS_CRITICAL),
+ ENTRY(CLK_OPS_PARENT_ENABLE),
+ ENTRY(CLK_DUTY_CYCLE_PARENT),
+#undef ENTRY
+};
+
+static int clk_flags_show(struct seq_file *s, void *data)
+{
+ struct clk_core *core = s->private;
+ unsigned long flags = core->flags;
+ unsigned int i;
+
+ for (i = 0; flags && i < ARRAY_SIZE(clk_flags); i++) {
+ if (flags & clk_flags[i].flag) {
+ seq_printf(s, "%s\n", clk_flags[i].name);
+ flags &= ~clk_flags[i].flag;
+ }
+ }
+ if (flags) {
+ /* Unknown flags */
+ seq_printf(s, "0x%lx\n", flags);
+ }
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_flags);
+
+static int possible_parents_show(struct seq_file *s, void *data)
+{
+ struct clk_core *core = s->private;
+ int i;
+
+ for (i = 0; i < core->num_parents - 1; i++)
+ seq_printf(s, "%s ", core->parent_names[i]);
+
+ seq_printf(s, "%s\n", core->parent_names[i]);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(possible_parents);
+
+static int clk_duty_cycle_show(struct seq_file *s, void *data)
+{
+ struct clk_core *core = s->private;
+ struct clk_duty *duty = &core->duty;
+
+ seq_printf(s, "%u/%u\n", duty->num, duty->den);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_duty_cycle);
+
+static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
+{
+ struct dentry *root;
+
+ if (!core || !pdentry)
+ return;
+
+ root = debugfs_create_dir(core->name, pdentry);
+ core->dentry = root;
+
+ debugfs_create_ulong("clk_rate", 0444, root, &core->rate);
+ debugfs_create_ulong("clk_accuracy", 0444, root, &core->accuracy);
+ debugfs_create_u32("clk_phase", 0444, root, &core->phase);
+ debugfs_create_file("clk_flags", 0444, root, core, &clk_flags_fops);
+ debugfs_create_u32("clk_prepare_count", 0444, root, &core->prepare_count);
+ debugfs_create_u32("clk_enable_count", 0444, root, &core->enable_count);
+ debugfs_create_u32("clk_protect_count", 0444, root, &core->protect_count);
+ debugfs_create_u32("clk_notifier_count", 0444, root, &core->notifier_count);
+ debugfs_create_file("clk_duty_cycle", 0444, root, core,
+ &clk_duty_cycle_fops);
+
+ if (core->num_parents > 1)
+ debugfs_create_file("clk_possible_parents", 0444, root, core,
+ &possible_parents_fops);
+
+ if (core->ops->debug_init)
+ core->ops->debug_init(core->hw, core->dentry);
+}
+
+/**
+ * clk_debug_register - add a clk node to the debugfs clk directory
+ * @core: the clk being added to the debugfs clk directory
+ *
+ * Dynamically adds a clk to the debugfs clk directory if debugfs has been
+ * initialized. Otherwise it bails out early since the debugfs clk directory
+ * will be created lazily by clk_debug_init as part of a late_initcall.
+ */
+static void clk_debug_register(struct clk_core *core)
+{
+ mutex_lock(&clk_debug_lock);
+ hlist_add_head(&core->debug_node, &clk_debug_list);
+ if (inited)
+ clk_debug_create_one(core, rootdir);
+ mutex_unlock(&clk_debug_lock);
+}
+
+ /**
+ * clk_debug_unregister - remove a clk node from the debugfs clk directory
+ * @core: the clk being removed from the debugfs clk directory
+ *
+ * Dynamically removes a clk and all its child nodes from the
+ * debugfs clk directory if clk->dentry points to debugfs created by
+ * clk_debug_register in __clk_core_init.
+ */
+static void clk_debug_unregister(struct clk_core *core)
+{
+ mutex_lock(&clk_debug_lock);
+ hlist_del_init(&core->debug_node);
+ debugfs_remove_recursive(core->dentry);
+ core->dentry = NULL;
+ mutex_unlock(&clk_debug_lock);
+}
+
+/**
+ * clk_debug_init - lazily populate the debugfs clk directory
+ *
+ * clks are often initialized very early during boot before memory can be
+ * dynamically allocated and well before debugfs is setup. This function
+ * populates the debugfs clk directory once at boot-time when we know that
+ * debugfs is setup. It should only be called once at boot-time, all other clks
+ * added dynamically will be done so with clk_debug_register.
+ */
+static int __init clk_debug_init(void)
+{
+ struct clk_core *core;
+
+ rootdir = debugfs_create_dir("clk", NULL);
+
+ debugfs_create_file("clk_summary", 0444, rootdir, &all_lists,
+ &clk_summary_fops);
+ debugfs_create_file("clk_dump", 0444, rootdir, &all_lists,
+ &clk_dump_fops);
+ debugfs_create_file("clk_orphan_summary", 0444, rootdir, &orphan_list,
+ &clk_summary_fops);
+ debugfs_create_file("clk_orphan_dump", 0444, rootdir, &orphan_list,
+ &clk_dump_fops);
+
+ mutex_lock(&clk_debug_lock);
+ hlist_for_each_entry(core, &clk_debug_list, debug_node)
+ clk_debug_create_one(core, rootdir);
+
+ inited = 1;
+ mutex_unlock(&clk_debug_lock);
+
+ return 0;
+}
+late_initcall(clk_debug_init);
+#else
+static inline void clk_debug_register(struct clk_core *core) { }
+static inline void clk_debug_reparent(struct clk_core *core,
+ struct clk_core *new_parent)
+{
+}
+static inline void clk_debug_unregister(struct clk_core *core)
+{
+}
+#endif
+
+/**
+ * __clk_core_init - initialize the data structures in a struct clk_core
+ * @core: clk_core being initialized
+ *
+ * Initializes the lists in struct clk_core, queries the hardware for the
+ * parent and rate and sets them both.
+ */
+static int __clk_core_init(struct clk_core *core)
+{
+ int i, ret;
+ struct clk_core *orphan;
+ struct hlist_node *tmp2;
+ unsigned long rate;
+
+ if (!core)
+ return -EINVAL;
+
+ clk_prepare_lock();
+
+ ret = clk_pm_runtime_get(core);
+ if (ret)
+ goto unlock;
+
+ /* check to see if a clock with this name is already registered */
+ if (clk_core_lookup(core->name)) {
+ pr_debug("%s: clk %s already initialized\n",
+ __func__, core->name);
+ ret = -EEXIST;
+ goto out;
+ }
+
+ /* check that clk_ops are sane. See Documentation/driver-api/clk.rst */
+ if (core->ops->set_rate &&
+ !((core->ops->round_rate || core->ops->determine_rate) &&
+ core->ops->recalc_rate)) {
+ pr_err("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (core->ops->set_parent && !core->ops->get_parent) {
+ pr_err("%s: %s must implement .get_parent & .set_parent\n",
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (core->num_parents > 1 && !core->ops->get_parent) {
+ pr_err("%s: %s must implement .get_parent as it has multi parents\n",
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (core->ops->set_rate_and_parent &&
+ !(core->ops->set_parent && core->ops->set_rate)) {
+ pr_err("%s: %s must implement .set_parent & .set_rate\n",
+ __func__, core->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* throw a WARN if any entries in parent_names are NULL */
+ for (i = 0; i < core->num_parents; i++)
+ WARN(!core->parent_names[i],
+ "%s: invalid NULL in %s's .parent_names\n",
+ __func__, core->name);
+
+ core->parent = __clk_init_parent(core);
+
+ /*
+ * Populate core->parent if parent has already been clk_core_init'd. If
+ * parent has not yet been clk_core_init'd then place clk in the orphan
+ * list. If clk doesn't have any parents 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 (core->parent) {
+ hlist_add_head(&core->child_node,
+ &core->parent->children);
+ core->orphan = core->parent->orphan;
+ } else if (!core->num_parents) {
+ hlist_add_head(&core->child_node, &clk_root_list);
+ core->orphan = false;
+ } else {
+ hlist_add_head(&core->child_node, &clk_orphan_list);
+ core->orphan = true;
+ }
+
+ /*
+ * 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 its use is discouraged.
+ */
+ if (core->ops->init)
+ core->ops->init(core->hw);
+
+ /*
+ * Set clk's accuracy. The preferred method is to use
+ * .recalc_accuracy. For simple clocks and lazy developers the default
+ * fallback is to use the parent's accuracy. If a clock doesn't have a
+ * parent (or is orphaned) then accuracy is set to zero (perfect
+ * clock).
+ */
+ if (core->ops->recalc_accuracy)
+ core->accuracy = core->ops->recalc_accuracy(core->hw,
+ __clk_get_accuracy(core->parent));
+ else if (core->parent)
+ core->accuracy = core->parent->accuracy;
+ else
+ core->accuracy = 0;
+
+ /*
+ * Set clk's phase.
+ * Since a phase is by definition relative to its parent, just
+ * query the current clock phase, or just assume it's in phase.
+ */
+ if (core->ops->get_phase)
+ core->phase = core->ops->get_phase(core->hw);
+ else
+ core->phase = 0;
+
+ /*
+ * Set clk's duty cycle.
+ */
+ clk_core_update_duty_cycle_nolock(core);
+
+ /*
+ * 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 (core->ops->recalc_rate)
+ rate = core->ops->recalc_rate(core->hw,
+ clk_core_get_rate_nolock(core->parent));
+ else if (core->parent)
+ rate = core->parent->rate;
+ else
+ rate = 0;
+ core->rate = core->req_rate = rate;
+
+ /*
+ * Enable CLK_IS_CRITICAL clocks so newly added critical clocks
+ * don't get accidentally disabled when walking the orphan tree and
+ * reparenting clocks
+ */
+ if (core->flags & CLK_IS_CRITICAL) {
+ unsigned long flags;
+
+ clk_core_prepare(core);
+
+ flags = clk_enable_lock();
+ clk_core_enable(core);
+ clk_enable_unlock(flags);
+ }
+
+ /*
+ * walk the list of orphan clocks and reparent any that newly finds a
+ * parent.
+ */
+ hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
+ struct clk_core *parent = __clk_init_parent(orphan);
+
+ /*
+ * We need to use __clk_set_parent_before() and _after() to
+ * to properly migrate any prepare/enable count of the orphan
+ * clock. This is important for CLK_IS_CRITICAL clocks, which
+ * are enabled during init but might not have a parent yet.
+ */
+ if (parent) {
+ /* update the clk tree topology */
+ __clk_set_parent_before(orphan, parent);
+ __clk_set_parent_after(orphan, parent, NULL);
+ __clk_recalc_accuracies(orphan);
+ __clk_recalc_rates(orphan, 0);
+ }
+ }
+
+ kref_init(&core->ref);
+out:
+ clk_pm_runtime_put(core);
+unlock:
+ clk_prepare_unlock();
+
+ if (!ret)
+ clk_debug_register(core);
+
+ return ret;
+}
+
+struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id,
+ const char *con_id)
+{
+ struct clk *clk;
+
+ /* This is to allow this function to be chained to others */
+ if (IS_ERR_OR_NULL(hw))
+ return ERR_CAST(hw);
+
+ clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+ if (!clk)
+ return ERR_PTR(-ENOMEM);
+
+ clk->core = hw->core;
+ clk->dev_id = dev_id;
+ clk->con_id = kstrdup_const(con_id, GFP_KERNEL);
+ clk->max_rate = ULONG_MAX;
+
+ clk_prepare_lock();
+ hlist_add_head(&clk->clks_node, &hw->core->clks);
+ clk_prepare_unlock();
+
+ return clk;
+}
+
+/* keep in sync with __clk_put */
+void __clk_free_clk(struct clk *clk)
+{
+ clk_prepare_lock();
+ hlist_del(&clk->clks_node);
+ clk_prepare_unlock();
+
+ kfree_const(clk->con_id);
+ kfree(clk);
+}
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * 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 conjunction with the
+ * rest of the clock API. In the event of an error clk_register will return an
+ * error code; drivers must test for an error code after calling clk_register.
+ */
+struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+{
+ int i, ret;
+ struct clk_core *core;
+
+ core = kzalloc(sizeof(*core), GFP_KERNEL);
+ if (!core) {
+ ret = -ENOMEM;
+ goto fail_out;
+ }
+
+ core->name = kstrdup_const(hw->init->name, GFP_KERNEL);
+ if (!core->name) {
+ ret = -ENOMEM;
+ goto fail_name;
+ }
+
+ if (WARN_ON(!hw->init->ops)) {
+ ret = -EINVAL;
+ goto fail_ops;
+ }
+ core->ops = hw->init->ops;
+
+ if (dev && pm_runtime_enabled(dev))
+ core->dev = dev;
+ if (dev && dev->driver)
+ core->owner = dev->driver->owner;
+ core->hw = hw;
+ core->flags = hw->init->flags;
+ core->num_parents = hw->init->num_parents;
+ core->min_rate = 0;
+ core->max_rate = ULONG_MAX;
+ hw->core = core;
+
+ /* allocate local copy in case parent_names is __initdata */
+ core->parent_names = kcalloc(core->num_parents, sizeof(char *),
+ GFP_KERNEL);
+
+ if (!core->parent_names) {
+ ret = -ENOMEM;
+ goto fail_parent_names;
+ }
+
+
+ /* copy each string name in case parent_names is __initdata */
+ for (i = 0; i < core->num_parents; i++) {
+ core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
+ GFP_KERNEL);
+ if (!core->parent_names[i]) {
+ ret = -ENOMEM;
+ goto fail_parent_names_copy;
+ }
+ }
+
+ /* avoid unnecessary string look-ups of clk_core's possible parents. */
+ core->parents = kcalloc(core->num_parents, sizeof(*core->parents),
+ GFP_KERNEL);
+ if (!core->parents) {
+ ret = -ENOMEM;
+ goto fail_parents;
+ };
+
+ INIT_HLIST_HEAD(&core->clks);
+
+ hw->clk = __clk_create_clk(hw, NULL, NULL);
+ if (IS_ERR(hw->clk)) {
+ ret = PTR_ERR(hw->clk);
+ goto fail_parents;
+ }
+
+ ret = __clk_core_init(core);
+ if (!ret)
+ return hw->clk;
+
+ __clk_free_clk(hw->clk);
+ hw->clk = NULL;
+
+fail_parents:
+ kfree(core->parents);
+fail_parent_names_copy:
+ while (--i >= 0)
+ kfree_const(core->parent_names[i]);
+ kfree(core->parent_names);
+fail_parent_names:
+fail_ops:
+ kfree_const(core->name);
+fail_name:
+ kfree(core);
+fail_out:
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(clk_register);
+
+/**
+ * clk_hw_register - register a clk_hw and return an error code
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * clk_hw_register is the primary interface for populating the clock tree with
+ * new clock nodes. It returns an integer equal to zero indicating success or
+ * less than zero indicating failure. Drivers must test for an error code after
+ * calling clk_hw_register().
+ */
+int clk_hw_register(struct device *dev, struct clk_hw *hw)
+{
+ return PTR_ERR_OR_ZERO(clk_register(dev, hw));
+}
+EXPORT_SYMBOL_GPL(clk_hw_register);
+
+/* Free memory allocated for a clock. */
+static void __clk_release(struct kref *ref)
+{
+ struct clk_core *core = container_of(ref, struct clk_core, ref);
+ int i = core->num_parents;
+
+ lockdep_assert_held(&prepare_lock);
+
+ kfree(core->parents);
+ while (--i >= 0)
+ kfree_const(core->parent_names[i]);
+
+ kfree(core->parent_names);
+ kfree_const(core->name);
+ kfree(core);
+}
+
+/*
+ * Empty clk_ops for unregistered clocks. These are used temporarily
+ * after clk_unregister() was called on a clock and until last clock
+ * consumer calls clk_put() and the struct clk object is freed.
+ */
+static int clk_nodrv_prepare_enable(struct clk_hw *hw)
+{
+ return -ENXIO;
+}
+
+static void clk_nodrv_disable_unprepare(struct clk_hw *hw)
+{
+ WARN_ON_ONCE(1);
+}
+
+static int clk_nodrv_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ return -ENXIO;
+}
+
+static int clk_nodrv_set_parent(struct clk_hw *hw, u8 index)
+{
+ return -ENXIO;
+}
+
+static const struct clk_ops clk_nodrv_ops = {
+ .enable = clk_nodrv_prepare_enable,
+ .disable = clk_nodrv_disable_unprepare,
+ .prepare = clk_nodrv_prepare_enable,
+ .unprepare = clk_nodrv_disable_unprepare,
+ .set_rate = clk_nodrv_set_rate,
+ .set_parent = clk_nodrv_set_parent,
+};
+
+/**
+ * clk_unregister - unregister a currently registered clock
+ * @clk: clock to unregister
+ */
+void clk_unregister(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_debug_unregister(clk->core);
+
+ clk_prepare_lock();
+
+ if (clk->core->ops == &clk_nodrv_ops) {
+ pr_err("%s: unregistered clock: %s\n", __func__,
+ clk->core->name);
+ goto unlock;
+ }
+ /*
+ * Assign empty clock ops for consumers that might still hold
+ * a reference to this clock.
+ */
+ flags = clk_enable_lock();
+ clk->core->ops = &clk_nodrv_ops;
+ clk_enable_unlock(flags);
+
+ if (!hlist_empty(&clk->core->children)) {
+ struct clk_core *child;
+ struct hlist_node *t;
+
+ /* Reparent all children to the orphan list. */
+ hlist_for_each_entry_safe(child, t, &clk->core->children,
+ child_node)
+ clk_core_set_parent_nolock(child, NULL);
+ }
+
+ hlist_del_init(&clk->core->child_node);
+
+ if (clk->core->prepare_count)
+ pr_warn("%s: unregistering prepared clock: %s\n",
+ __func__, clk->core->name);
+
+ if (clk->core->protect_count)
+ pr_warn("%s: unregistering protected clock: %s\n",
+ __func__, clk->core->name);
+
+ kref_put(&clk->core->ref, __clk_release);
+unlock:
+ clk_prepare_unlock();
+}
+EXPORT_SYMBOL_GPL(clk_unregister);
+
+/**
+ * clk_hw_unregister - unregister a currently registered clk_hw
+ * @hw: hardware-specific clock data to unregister
+ */
+void clk_hw_unregister(struct clk_hw *hw)
+{
+ clk_unregister(hw->clk);
+}
+EXPORT_SYMBOL_GPL(clk_hw_unregister);
+
+static void devm_clk_release(struct device *dev, void *res)
+{
+ clk_unregister(*(struct clk **)res);
+}
+
+static void devm_clk_hw_release(struct device *dev, void *res)
+{
+ clk_hw_unregister(*(struct clk_hw **)res);
+}
+
+/**
+ * devm_clk_register - resource managed clk_register()
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * Managed clk_register(). Clocks returned from this function are
+ * automatically clk_unregister()ed on driver detach. See clk_register() for
+ * more information.
+ */
+struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw)
+{
+ struct clk *clk;
+ struct clk **clkp;
+
+ clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL);
+ if (!clkp)
+ return ERR_PTR(-ENOMEM);
+
+ clk = clk_register(dev, hw);
+ if (!IS_ERR(clk)) {
+ *clkp = clk;
+ devres_add(dev, clkp);
+ } else {
+ devres_free(clkp);
+ }
+
+ return clk;
+}
+EXPORT_SYMBOL_GPL(devm_clk_register);
+
+/**
+ * devm_clk_hw_register - resource managed clk_hw_register()
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * Managed clk_hw_register(). Clocks registered by this function are
+ * automatically clk_hw_unregister()ed on driver detach. See clk_hw_register()
+ * for more information.
+ */
+int devm_clk_hw_register(struct device *dev, struct clk_hw *hw)
+{
+ struct clk_hw **hwp;
+ int ret;
+
+ hwp = devres_alloc(devm_clk_hw_release, sizeof(*hwp), GFP_KERNEL);
+ if (!hwp)
+ return -ENOMEM;
+
+ ret = clk_hw_register(dev, hw);
+ if (!ret) {
+ *hwp = hw;
+ devres_add(dev, hwp);
+ } else {
+ devres_free(hwp);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devm_clk_hw_register);
+
+static int devm_clk_match(struct device *dev, void *res, void *data)
+{
+ struct clk *c = res;
+ if (WARN_ON(!c))
+ return 0;
+ return c == data;
+}
+
+static int devm_clk_hw_match(struct device *dev, void *res, void *data)
+{
+ struct clk_hw *hw = res;
+
+ if (WARN_ON(!hw))
+ return 0;
+ return hw == data;
+}
+
+/**
+ * devm_clk_unregister - resource managed clk_unregister()
+ * @clk: clock to unregister
+ *
+ * Deallocate a clock allocated with devm_clk_register(). Normally
+ * this function will not need to be called and the resource management
+ * code will ensure that the resource is freed.
+ */
+void devm_clk_unregister(struct device *dev, struct clk *clk)
+{
+ WARN_ON(devres_release(dev, devm_clk_release, devm_clk_match, clk));
+}
+EXPORT_SYMBOL_GPL(devm_clk_unregister);
+
+/**
+ * devm_clk_hw_unregister - resource managed clk_hw_unregister()
+ * @dev: device that is unregistering the hardware-specific clock data
+ * @hw: link to hardware-specific clock data
+ *
+ * Unregister a clk_hw registered with devm_clk_hw_register(). Normally
+ * this function will not need to be called and the resource management
+ * code will ensure that the resource is freed.
+ */
+void devm_clk_hw_unregister(struct device *dev, struct clk_hw *hw)
+{
+ WARN_ON(devres_release(dev, devm_clk_hw_release, devm_clk_hw_match,
+ hw));
+}
+EXPORT_SYMBOL_GPL(devm_clk_hw_unregister);
+
+/*
+ * clkdev helpers
+ */
+int __clk_get(struct clk *clk)
+{
+ struct clk_core *core = !clk ? NULL : clk->core;
+
+ if (core) {
+ if (!try_module_get(core->owner))
+ return 0;
+
+ kref_get(&core->ref);
+ }
+ return 1;
+}
+
+/* keep in sync with __clk_free_clk */
+void __clk_put(struct clk *clk)
+{
+ struct module *owner;
+
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_prepare_lock();
+
+ /*
+ * Before calling clk_put, all calls to clk_rate_exclusive_get() from a
+ * given user should be balanced with calls to clk_rate_exclusive_put()
+ * and by that same consumer
+ */
+ if (WARN_ON(clk->exclusive_count)) {
+ /* We voiced our concern, let's sanitize the situation */
+ clk->core->protect_count -= (clk->exclusive_count - 1);
+ clk_core_rate_unprotect(clk->core);
+ clk->exclusive_count = 0;
+ }
+
+ hlist_del(&clk->clks_node);
+ if (clk->min_rate > clk->core->req_rate ||
+ clk->max_rate < clk->core->req_rate)
+ clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+
+ owner = clk->core->owner;
+ kref_put(&clk->core->ref, __clk_release);
+
+ clk_prepare_unlock();
+
+ module_put(owner);
+
+ kfree_const(clk->con_id);
+ kfree(clk);
+}
+
+/*** 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.
+ *
+ * In all notification cases (pre, post and abort rate change) the original
+ * clock rate is passed to the callback via struct clk_notifier_data.old_rate
+ * and the new frequency is passed via struct clk_notifier_data.new_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;
+
+ clk_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(*cn), 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->core->notifier_count++;
+
+out:
+ clk_prepare_unlock();
+
+ 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;
+
+ clk_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->core->notifier_count--;
+
+ /* XXX the notifier code should handle this better */
+ if (!cn->notifier_head.head) {
+ srcu_cleanup_notifier_head(&cn->notifier_head);
+ list_del(&cn->node);
+ kfree(cn);
+ }
+
+ } else {
+ ret = -ENOENT;
+ }
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_notifier_unregister);
+
+#ifdef CONFIG_OF
+/**
+ * struct of_clk_provider - Clock provider registration structure
+ * @link: Entry in global list of clock providers
+ * @node: Pointer to device tree node of clock provider
+ * @get: Get clock callback. Returns NULL or a struct clk for the
+ * given clock specifier
+ * @data: context pointer to be passed into @get callback
+ */
+struct of_clk_provider {
+ struct list_head link;
+
+ struct device_node *node;
+ struct clk *(*get)(struct of_phandle_args *clkspec, void *data);
+ struct clk_hw *(*get_hw)(struct of_phandle_args *clkspec, void *data);
+ void *data;
+};
+
+static const struct of_device_id __clk_of_table_sentinel
+ __used __section(__clk_of_table_end);
+
+static LIST_HEAD(of_clk_providers);
+static DEFINE_MUTEX(of_clk_mutex);
+
+struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
+ void *data)
+{
+ return data;
+}
+EXPORT_SYMBOL_GPL(of_clk_src_simple_get);
+
+struct clk_hw *of_clk_hw_simple_get(struct of_phandle_args *clkspec, void *data)
+{
+ return data;
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_simple_get);
+
+struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data)
+{
+ struct clk_onecell_data *clk_data = data;
+ unsigned int idx = clkspec->args[0];
+
+ if (idx >= clk_data->clk_num) {
+ pr_err("%s: invalid clock index %u\n", __func__, idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return clk_data->clks[idx];
+}
+EXPORT_SYMBOL_GPL(of_clk_src_onecell_get);
+
+struct clk_hw *
+of_clk_hw_onecell_get(struct of_phandle_args *clkspec, void *data)
+{
+ struct clk_hw_onecell_data *hw_data = data;
+ unsigned int idx = clkspec->args[0];
+
+ if (idx >= hw_data->num) {
+ pr_err("%s: invalid index %u\n", __func__, idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return hw_data->hws[idx];
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_onecell_get);
+
+/**
+ * of_clk_add_provider() - Register a clock provider for a node
+ * @np: Device node pointer associated with clock provider
+ * @clk_src_get: callback for decoding clock
+ * @data: context pointer for @clk_src_get callback.
+ */
+int of_clk_add_provider(struct device_node *np,
+ struct clk *(*clk_src_get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data)
+{
+ struct of_clk_provider *cp;
+ int ret;
+
+ cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+ if (!cp)
+ return -ENOMEM;
+
+ cp->node = of_node_get(np);
+ cp->data = data;
+ cp->get = clk_src_get;
+
+ mutex_lock(&of_clk_mutex);
+ list_add(&cp->link, &of_clk_providers);
+ mutex_unlock(&of_clk_mutex);
+ pr_debug("Added clock from %pOF\n", np);
+
+ ret = of_clk_set_defaults(np, true);
+ if (ret < 0)
+ of_clk_del_provider(np);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_clk_add_provider);
+
+/**
+ * of_clk_add_hw_provider() - Register a clock provider for a node
+ * @np: Device node pointer associated with clock provider
+ * @get: callback for decoding clk_hw
+ * @data: context pointer for @get callback.
+ */
+int of_clk_add_hw_provider(struct device_node *np,
+ struct clk_hw *(*get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data)
+{
+ struct of_clk_provider *cp;
+ int ret;
+
+ cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+ if (!cp)
+ return -ENOMEM;
+
+ cp->node = of_node_get(np);
+ cp->data = data;
+ cp->get_hw = get;
+
+ mutex_lock(&of_clk_mutex);
+ list_add(&cp->link, &of_clk_providers);
+ mutex_unlock(&of_clk_mutex);
+ pr_debug("Added clk_hw provider from %pOF\n", np);
+
+ ret = of_clk_set_defaults(np, true);
+ if (ret < 0)
+ of_clk_del_provider(np);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_clk_add_hw_provider);
+
+static void devm_of_clk_release_provider(struct device *dev, void *res)
+{
+ of_clk_del_provider(*(struct device_node **)res);
+}
+
+int devm_of_clk_add_hw_provider(struct device *dev,
+ struct clk_hw *(*get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data)
+{
+ struct device_node **ptr, *np;
+ int ret;
+
+ ptr = devres_alloc(devm_of_clk_release_provider, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ np = dev->of_node;
+ ret = of_clk_add_hw_provider(np, get, data);
+ if (!ret) {
+ *ptr = np;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devm_of_clk_add_hw_provider);
+
+/**
+ * of_clk_del_provider() - Remove a previously registered clock provider
+ * @np: Device node pointer associated with clock provider
+ */
+void of_clk_del_provider(struct device_node *np)
+{
+ struct of_clk_provider *cp;
+
+ mutex_lock(&of_clk_mutex);
+ list_for_each_entry(cp, &of_clk_providers, link) {
+ if (cp->node == np) {
+ list_del(&cp->link);
+ of_node_put(cp->node);
+ kfree(cp);
+ break;
+ }
+ }
+ mutex_unlock(&of_clk_mutex);
+}
+EXPORT_SYMBOL_GPL(of_clk_del_provider);
+
+static int devm_clk_provider_match(struct device *dev, void *res, void *data)
+{
+ struct device_node **np = res;
+
+ if (WARN_ON(!np || !*np))
+ return 0;
+
+ return *np == data;
+}
+
+void devm_of_clk_del_provider(struct device *dev)
+{
+ int ret;
+
+ ret = devres_release(dev, devm_of_clk_release_provider,
+ devm_clk_provider_match, dev->of_node);
+
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL(devm_of_clk_del_provider);
+
+static struct clk_hw *
+__of_clk_get_hw_from_provider(struct of_clk_provider *provider,
+ struct of_phandle_args *clkspec)
+{
+ struct clk *clk;
+
+ if (provider->get_hw)
+ return provider->get_hw(clkspec, provider->data);
+
+ clk = provider->get(clkspec, provider->data);
+ if (IS_ERR(clk))
+ return ERR_CAST(clk);
+ return __clk_get_hw(clk);
+}
+
+struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
+ const char *dev_id, const char *con_id)
+{
+ struct of_clk_provider *provider;
+ struct clk *clk = ERR_PTR(-EPROBE_DEFER);
+ struct clk_hw *hw;
+
+ if (!clkspec)
+ return ERR_PTR(-EINVAL);
+
+ /* Check if we have such a provider in our array */
+ mutex_lock(&of_clk_mutex);
+ list_for_each_entry(provider, &of_clk_providers, link) {
+ if (provider->node == clkspec->np) {
+ hw = __of_clk_get_hw_from_provider(provider, clkspec);
+ clk = __clk_create_clk(hw, dev_id, con_id);
+ }
+
+ if (!IS_ERR(clk)) {
+ if (!__clk_get(clk)) {
+ __clk_free_clk(clk);
+ clk = ERR_PTR(-ENOENT);
+ }
+
+ break;
+ }
+ }
+ mutex_unlock(&of_clk_mutex);
+
+ return clk;
+}
+
+/**
+ * of_clk_get_from_provider() - Lookup a clock from a clock provider
+ * @clkspec: pointer to a clock specifier data structure
+ *
+ * This function looks up a struct clk from the registered list of clock
+ * providers, an input is a clock specifier data structure as returned
+ * from the of_parse_phandle_with_args() function call.
+ */
+struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
+{
+ return __of_clk_get_from_provider(clkspec, NULL, __func__);
+}
+EXPORT_SYMBOL_GPL(of_clk_get_from_provider);
+
+/**
+ * of_clk_get_parent_count() - Count the number of clocks a device node has
+ * @np: device node to count
+ *
+ * Returns: The number of clocks that are possible parents of this node
+ */
+unsigned int of_clk_get_parent_count(struct device_node *np)
+{
+ int count;
+
+ count = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ if (count < 0)
+ return 0;
+
+ return count;
+}
+EXPORT_SYMBOL_GPL(of_clk_get_parent_count);
+
+const char *of_clk_get_parent_name(struct device_node *np, int index)
+{
+ struct of_phandle_args clkspec;
+ struct property *prop;
+ const char *clk_name;
+ const __be32 *vp;
+ u32 pv;
+ int rc;
+ int count;
+ struct clk *clk;
+
+ rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index,
+ &clkspec);
+ if (rc)
+ return NULL;
+
+ index = clkspec.args_count ? clkspec.args[0] : 0;
+ count = 0;
+
+ /* if there is an indices property, use it to transfer the index
+ * specified into an array offset for the clock-output-names property.
+ */
+ of_property_for_each_u32(clkspec.np, "clock-indices", prop, vp, pv) {
+ if (index == pv) {
+ index = count;
+ break;
+ }
+ count++;
+ }
+ /* We went off the end of 'clock-indices' without finding it */
+ if (prop && !vp)
+ return NULL;
+
+ if (of_property_read_string_index(clkspec.np, "clock-output-names",
+ index,
+ &clk_name) < 0) {
+ /*
+ * Best effort to get the name if the clock has been
+ * registered with the framework. If the clock isn't
+ * registered, we return the node name as the name of
+ * the clock as long as #clock-cells = 0.
+ */
+ clk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(clk)) {
+ if (clkspec.args_count == 0)
+ clk_name = clkspec.np->name;
+ else
+ clk_name = NULL;
+ } else {
+ clk_name = __clk_get_name(clk);
+ clk_put(clk);
+ }
+ }
+
+
+ of_node_put(clkspec.np);
+ return clk_name;
+}
+EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
+
+/**
+ * of_clk_parent_fill() - Fill @parents with names of @np's parents and return
+ * number of parents
+ * @np: Device node pointer associated with clock provider
+ * @parents: pointer to char array that hold the parents' names
+ * @size: size of the @parents array
+ *
+ * Return: number of parents for the clock node.
+ */
+int of_clk_parent_fill(struct device_node *np, const char **parents,
+ unsigned int size)
+{
+ unsigned int i = 0;
+
+ while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
+ i++;
+
+ return i;
+}
+EXPORT_SYMBOL_GPL(of_clk_parent_fill);
+
+struct clock_provider {
+ void (*clk_init_cb)(struct device_node *);
+ struct device_node *np;
+ struct list_head node;
+};
+
+/*
+ * This function looks for a parent clock. If there is one, then it
+ * checks that the provider for this parent clock was initialized, in
+ * this case the parent clock will be ready.
+ */
+static int parent_ready(struct device_node *np)
+{
+ int i = 0;
+
+ while (true) {
+ struct clk *clk = of_clk_get(np, i);
+
+ /* this parent is ready we can check the next one */
+ if (!IS_ERR(clk)) {
+ clk_put(clk);
+ i++;
+ continue;
+ }
+
+ /* at least one parent is not ready, we exit now */
+ if (PTR_ERR(clk) == -EPROBE_DEFER)
+ return 0;
+
+ /*
+ * Here we make assumption that the device tree is
+ * written correctly. So an error means that there is
+ * no more parent. As we didn't exit yet, then the
+ * previous parent are ready. If there is no clock
+ * parent, no need to wait for them, then we can
+ * consider their absence as being ready
+ */
+ return 1;
+ }
+}
+
+/**
+ * of_clk_detect_critical() - set CLK_IS_CRITICAL flag from Device Tree
+ * @np: Device node pointer associated with clock provider
+ * @index: clock index
+ * @flags: pointer to top-level framework flags
+ *
+ * Detects if the clock-critical property exists and, if so, sets the
+ * corresponding CLK_IS_CRITICAL flag.
+ *
+ * Do not use this function. It exists only for legacy Device Tree
+ * bindings, such as the one-clock-per-node style that are outdated.
+ * Those bindings typically put all clock data into .dts and the Linux
+ * driver has no clock data, thus making it impossible to set this flag
+ * correctly from the driver. Only those drivers may call
+ * of_clk_detect_critical from their setup functions.
+ *
+ * Return: error code or zero on success
+ */
+int of_clk_detect_critical(struct device_node *np,
+ int index, unsigned long *flags)
+{
+ struct property *prop;
+ const __be32 *cur;
+ uint32_t idx;
+
+ if (!np || !flags)
+ return -EINVAL;
+
+ of_property_for_each_u32(np, "clock-critical", prop, cur, idx)
+ if (index == idx)
+ *flags |= CLK_IS_CRITICAL;
+
+ return 0;
+}
+
+/**
+ * of_clk_init() - Scan and init clock providers from the DT
+ * @matches: array of compatible values and init functions for providers.
+ *
+ * This function scans the device tree for matching clock providers
+ * and calls their initialization functions. It also does it by trying
+ * to follow the dependencies.
+ */
+void __init of_clk_init(const struct of_device_id *matches)
+{
+ const struct of_device_id *match;
+ struct device_node *np;
+ struct clock_provider *clk_provider, *next;
+ bool is_init_done;
+ bool force = false;
+ LIST_HEAD(clk_provider_list);
+
+ if (!matches)
+ matches = &__clk_of_table;
+
+ /* First prepare the list of the clocks providers */
+ for_each_matching_node_and_match(np, matches, &match) {
+ struct clock_provider *parent;
+
+ if (!of_device_is_available(np))
+ continue;
+
+ parent = kzalloc(sizeof(*parent), GFP_KERNEL);
+ if (!parent) {
+ list_for_each_entry_safe(clk_provider, next,
+ &clk_provider_list, node) {
+ list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
+ kfree(clk_provider);
+ }
+ of_node_put(np);
+ return;
+ }
+
+ parent->clk_init_cb = match->data;
+ parent->np = of_node_get(np);
+ list_add_tail(&parent->node, &clk_provider_list);
+ }
+
+ while (!list_empty(&clk_provider_list)) {
+ is_init_done = false;
+ list_for_each_entry_safe(clk_provider, next,
+ &clk_provider_list, node) {
+ if (force || parent_ready(clk_provider->np)) {
+
+ /* Don't populate platform devices */
+ of_node_set_flag(clk_provider->np,
+ OF_POPULATED);
+
+ clk_provider->clk_init_cb(clk_provider->np);
+ of_clk_set_defaults(clk_provider->np, true);
+
+ list_del(&clk_provider->node);
+ of_node_put(clk_provider->np);
+ kfree(clk_provider);
+ is_init_done = true;
+ }
+ }
+
+ /*
+ * We didn't manage to initialize any of the
+ * remaining providers during the last loop, so now we
+ * initialize all the remaining ones unconditionally
+ * in case the clock parent was not mandatory
+ */
+ if (!is_init_done)
+ force = true;
+ }
+}
+#endif