aboutsummaryrefslogtreecommitdiff
path: root/drivers/clk/clk.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r--drivers/clk/clk.c1530
1 files changed, 1178 insertions, 352 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 251e45d6024..8b73edef151 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -18,23 +18,217 @@
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/sched.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);
+/*** 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)
+{
+ unsigned long flags;
+
+ if (!spin_trylock_irqsave(&enable_lock, flags)) {
+ if (enable_owner == current) {
+ enable_refcnt++;
+ 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)
+{
+ WARN_ON_ONCE(enable_owner != current);
+ WARN_ON_ONCE(enable_refcnt == 0);
+
+ if (--enable_refcnt)
+ return;
+ enable_owner = NULL;
+ spin_unlock_irqrestore(&enable_lock, flags);
+}
+
/*** debugfs support ***/
-#ifdef CONFIG_COMMON_CLK_DEBUG
+#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
static struct dentry *rootdir;
static struct dentry *orphandir;
static int inited = 0;
+static void clk_summary_show_one(struct seq_file *s, struct clk *c, int level)
+{
+ if (!c)
+ return;
+
+ seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu\n",
+ level * 3 + 1, "",
+ 30 - level * 3, c->name,
+ c->enable_count, c->prepare_count, clk_get_rate(c),
+ clk_get_accuracy(c));
+}
+
+static void clk_summary_show_subtree(struct seq_file *s, struct clk *c,
+ int level)
+{
+ struct clk *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 *c;
+
+ seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy\n");
+ seq_puts(s, "--------------------------------------------------------------------------------\n");
+
+ clk_prepare_lock();
+
+ hlist_for_each_entry(c, &clk_root_list, child_node)
+ clk_summary_show_subtree(s, c, 0);
+
+ hlist_for_each_entry(c, &clk_orphan_list, child_node)
+ clk_summary_show_subtree(s, c, 0);
+
+ clk_prepare_unlock();
+
+ return 0;
+}
+
+
+static int clk_summary_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_summary_show, inode->i_private);
+}
+
+static const struct file_operations clk_summary_fops = {
+ .open = clk_summary_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void clk_dump_one(struct seq_file *s, struct clk *c, int level)
+{
+ if (!c)
+ return;
+
+ 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, "\"rate\": %lu", clk_get_rate(c));
+ seq_printf(s, "\"accuracy\": %lu", clk_get_accuracy(c));
+}
+
+static void clk_dump_subtree(struct seq_file *s, struct clk *c, int level)
+{
+ struct clk *child;
+
+ if (!c)
+ return;
+
+ clk_dump_one(s, c, level);
+
+ hlist_for_each_entry(child, &c->children, child_node) {
+ seq_printf(s, ",");
+ clk_dump_subtree(s, child, level + 1);
+ }
+
+ seq_printf(s, "}");
+}
+
+static int clk_dump(struct seq_file *s, void *data)
+{
+ struct clk *c;
+ bool first_node = true;
+
+ seq_printf(s, "{");
+
+ clk_prepare_lock();
+
+ hlist_for_each_entry(c, &clk_root_list, child_node) {
+ if (!first_node)
+ seq_printf(s, ",");
+ first_node = false;
+ clk_dump_subtree(s, c, 0);
+ }
+
+ hlist_for_each_entry(c, &clk_orphan_list, child_node) {
+ seq_printf(s, ",");
+ clk_dump_subtree(s, c, 0);
+ }
+
+ clk_prepare_unlock();
+
+ seq_printf(s, "}");
+ return 0;
+}
+
+
+static int clk_dump_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_dump, inode->i_private);
+}
+
+static const struct file_operations clk_dump_fops = {
+ .open = clk_dump_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
/* caller must hold prepare_lock */
static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry)
{
@@ -57,6 +251,11 @@ static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry)
if (!d)
goto err_out;
+ d = debugfs_create_u32("clk_accuracy", S_IRUGO, clk->dentry,
+ (u32 *)&clk->accuracy);
+ if (!d)
+ goto err_out;
+
d = debugfs_create_x32("clk_flags", S_IRUGO, clk->dentry,
(u32 *)&clk->flags);
if (!d)
@@ -77,11 +276,16 @@ static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry)
if (!d)
goto err_out;
+ if (clk->ops->debug_init)
+ if (clk->ops->debug_init(clk->hw, clk->dentry))
+ goto err_out;
+
ret = 0;
goto out;
err_out:
- debugfs_remove(clk->dentry);
+ debugfs_remove_recursive(clk->dentry);
+ clk->dentry = NULL;
out:
return ret;
}
@@ -90,7 +294,6 @@ out:
static int clk_debug_create_subtree(struct clk *clk, struct dentry *pdentry)
{
struct clk *child;
- struct hlist_node *tmp;
int ret = -EINVAL;;
if (!clk || !pdentry)
@@ -101,7 +304,7 @@ static int clk_debug_create_subtree(struct clk *clk, struct dentry *pdentry)
if (ret)
goto out;
- hlist_for_each_entry(child, tmp, &clk->children, child_node)
+ hlist_for_each_entry(child, &clk->children, child_node)
clk_debug_create_subtree(child, clk->dentry);
ret = 0;
@@ -152,6 +355,54 @@ out:
return ret;
}
+ /**
+ * clk_debug_unregister - remove a clk node from the debugfs clk tree
+ * @clk: the clk being removed from the debugfs clk tree
+ *
+ * Dynamically removes a clk and all it's children clk nodes from the
+ * debugfs clk tree if clk->dentry points to debugfs created by
+ * clk_debug_register in __clk_init.
+ *
+ * Caller must hold prepare_lock.
+ */
+static void clk_debug_unregister(struct clk *clk)
+{
+ debugfs_remove_recursive(clk->dentry);
+}
+
+/**
+ * clk_debug_reparent - reparent clk node in the debugfs clk tree
+ * @clk: the clk being reparented
+ * @new_parent: the new clk parent, may be NULL
+ *
+ * Rename clk entry in the debugfs clk tree if debugfs has been
+ * initialized. Otherwise it bails out early since the debugfs clk tree
+ * will be created lazily by clk_debug_init as part of a late_initcall.
+ *
+ * Caller must hold prepare_lock.
+ */
+static void clk_debug_reparent(struct clk *clk, struct clk *new_parent)
+{
+ struct dentry *d;
+ struct dentry *new_parent_d;
+
+ if (!inited)
+ return;
+
+ if (new_parent)
+ new_parent_d = new_parent->dentry;
+ else
+ new_parent_d = orphandir;
+
+ d = debugfs_rename(clk->dentry->d_parent, clk->dentry,
+ new_parent_d, clk->name);
+ if (d)
+ clk->dentry = d;
+ else
+ pr_debug("%s: failed to rename debugfs entry for %s\n",
+ __func__, clk->name);
+}
+
/**
* clk_debug_init - lazily create the debugfs clk tree visualization
*
@@ -167,51 +418,91 @@ out:
static int __init clk_debug_init(void)
{
struct clk *clk;
- struct hlist_node *tmp;
+ struct dentry *d;
rootdir = debugfs_create_dir("clk", NULL);
if (!rootdir)
return -ENOMEM;
+ d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, NULL,
+ &clk_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, NULL,
+ &clk_dump_fops);
+ if (!d)
+ return -ENOMEM;
+
orphandir = debugfs_create_dir("orphans", rootdir);
if (!orphandir)
return -ENOMEM;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
- hlist_for_each_entry(clk, tmp, &clk_root_list, child_node)
+ hlist_for_each_entry(clk, &clk_root_list, child_node)
clk_debug_create_subtree(clk, rootdir);
- hlist_for_each_entry(clk, tmp, &clk_orphan_list, child_node)
+ hlist_for_each_entry(clk, &clk_orphan_list, child_node)
clk_debug_create_subtree(clk, orphandir);
inited = 1;
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return 0;
}
late_initcall(clk_debug_init);
#else
static inline int clk_debug_register(struct clk *clk) { return 0; }
+static inline void clk_debug_reparent(struct clk *clk, struct clk *new_parent)
+{
+}
+static inline void clk_debug_unregister(struct clk *clk)
+{
+}
#endif
/* caller must hold prepare_lock */
+static void clk_unprepare_unused_subtree(struct clk *clk)
+{
+ struct clk *child;
+
+ if (!clk)
+ return;
+
+ hlist_for_each_entry(child, &clk->children, child_node)
+ clk_unprepare_unused_subtree(child);
+
+ if (clk->prepare_count)
+ return;
+
+ if (clk->flags & CLK_IGNORE_UNUSED)
+ return;
+
+ if (__clk_is_prepared(clk)) {
+ if (clk->ops->unprepare_unused)
+ clk->ops->unprepare_unused(clk->hw);
+ else if (clk->ops->unprepare)
+ clk->ops->unprepare(clk->hw);
+ }
+}
+
+/* caller must hold prepare_lock */
static void clk_disable_unused_subtree(struct clk *clk)
{
struct clk *child;
- struct hlist_node *tmp;
unsigned long flags;
if (!clk)
goto out;
- hlist_for_each_entry(child, tmp, &clk->children, child_node)
+ hlist_for_each_entry(child, &clk->children, child_node)
clk_disable_unused_subtree(child);
- spin_lock_irqsave(&enable_lock, flags);
+ flags = clk_enable_lock();
if (clk->enable_count)
goto unlock_out;
@@ -232,59 +523,95 @@ static void clk_disable_unused_subtree(struct clk *clk)
}
unlock_out:
- spin_unlock_irqrestore(&enable_lock, flags);
+ clk_enable_unlock(flags);
out:
return;
}
+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 *clk;
- struct hlist_node *tmp;
- mutex_lock(&prepare_lock);
+ if (clk_ignore_unused) {
+ pr_warn("clk: Not disabling unused clocks\n");
+ return 0;
+ }
+
+ clk_prepare_lock();
- hlist_for_each_entry(clk, tmp, &clk_root_list, child_node)
+ hlist_for_each_entry(clk, &clk_root_list, child_node)
clk_disable_unused_subtree(clk);
- hlist_for_each_entry(clk, tmp, &clk_orphan_list, child_node)
+ hlist_for_each_entry(clk, &clk_orphan_list, child_node)
clk_disable_unused_subtree(clk);
- mutex_unlock(&prepare_lock);
+ hlist_for_each_entry(clk, &clk_root_list, child_node)
+ clk_unprepare_unused_subtree(clk);
+
+ hlist_for_each_entry(clk, &clk_orphan_list, child_node)
+ clk_unprepare_unused_subtree(clk);
+
+ clk_prepare_unlock();
return 0;
}
-late_initcall(clk_disable_unused);
+late_initcall_sync(clk_disable_unused);
/*** helper functions ***/
-inline const char *__clk_get_name(struct clk *clk)
+const char *__clk_get_name(struct clk *clk)
{
return !clk ? NULL : clk->name;
}
+EXPORT_SYMBOL_GPL(__clk_get_name);
-inline struct clk_hw *__clk_get_hw(struct clk *clk)
+struct clk_hw *__clk_get_hw(struct clk *clk)
{
return !clk ? NULL : clk->hw;
}
+EXPORT_SYMBOL_GPL(__clk_get_hw);
-inline u8 __clk_get_num_parents(struct clk *clk)
+u8 __clk_get_num_parents(struct clk *clk)
{
return !clk ? 0 : clk->num_parents;
}
+EXPORT_SYMBOL_GPL(__clk_get_num_parents);
-inline struct clk *__clk_get_parent(struct clk *clk)
+struct clk *__clk_get_parent(struct clk *clk)
{
return !clk ? NULL : clk->parent;
}
+EXPORT_SYMBOL_GPL(__clk_get_parent);
-inline unsigned int __clk_get_enable_count(struct clk *clk)
+struct clk *clk_get_parent_by_index(struct clk *clk, u8 index)
+{
+ if (!clk || index >= clk->num_parents)
+ return NULL;
+ else if (!clk->parents)
+ return __clk_lookup(clk->parent_names[index]);
+ else if (!clk->parents[index])
+ return clk->parents[index] =
+ __clk_lookup(clk->parent_names[index]);
+ else
+ return clk->parents[index];
+}
+EXPORT_SYMBOL_GPL(clk_get_parent_by_index);
+
+unsigned int __clk_get_enable_count(struct clk *clk)
{
return !clk ? 0 : clk->enable_count;
}
-inline unsigned int __clk_get_prepare_count(struct clk *clk)
+unsigned int __clk_get_prepare_count(struct clk *clk)
{
return !clk ? 0 : clk->prepare_count;
}
@@ -309,11 +636,42 @@ unsigned long __clk_get_rate(struct clk *clk)
out:
return ret;
}
+EXPORT_SYMBOL_GPL(__clk_get_rate);
-inline unsigned long __clk_get_flags(struct clk *clk)
+unsigned long __clk_get_accuracy(struct clk *clk)
+{
+ if (!clk)
+ return 0;
+
+ return clk->accuracy;
+}
+
+unsigned long __clk_get_flags(struct clk *clk)
{
return !clk ? 0 : clk->flags;
}
+EXPORT_SYMBOL_GPL(__clk_get_flags);
+
+bool __clk_is_prepared(struct clk *clk)
+{
+ int ret;
+
+ if (!clk)
+ return false;
+
+ /*
+ * .is_prepared is optional for clocks that can prepare
+ * fall back to software usage counter if it is missing
+ */
+ if (!clk->ops->is_prepared) {
+ ret = clk->prepare_count ? 1 : 0;
+ goto out;
+ }
+
+ ret = clk->ops->is_prepared(clk->hw);
+out:
+ return !!ret;
+}
bool __clk_is_enabled(struct clk *clk)
{
@@ -335,17 +693,17 @@ bool __clk_is_enabled(struct clk *clk)
out:
return !!ret;
}
+EXPORT_SYMBOL_GPL(__clk_is_enabled);
static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk)
{
struct clk *child;
struct clk *ret;
- struct hlist_node *tmp;
if (!strcmp(clk->name, name))
return clk;
- hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+ hlist_for_each_entry(child, &clk->children, child_node) {
ret = __clk_lookup_subtree(name, child);
if (ret)
return ret;
@@ -358,20 +716,19 @@ struct clk *__clk_lookup(const char *name)
{
struct clk *root_clk;
struct clk *ret;
- struct hlist_node *tmp;
if (!name)
return NULL;
/* search the 'proper' clk tree first */
- hlist_for_each_entry(root_clk, tmp, &clk_root_list, child_node) {
+ 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, tmp, &clk_orphan_list, child_node) {
+ hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) {
ret = __clk_lookup_subtree(name, root_clk);
if (ret)
return ret;
@@ -380,6 +737,56 @@ struct clk *__clk_lookup(const char *name)
return NULL;
}
+/*
+ * 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.
+ */
+long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *best_parent_rate,
+ struct clk **best_parent_p)
+{
+ struct clk *clk = hw->clk, *parent, *best_parent = NULL;
+ int i, num_parents;
+ unsigned long parent_rate, best = 0;
+
+ /* if NO_REPARENT flag set, pass through to current parent */
+ if (clk->flags & CLK_SET_RATE_NO_REPARENT) {
+ parent = clk->parent;
+ if (clk->flags & CLK_SET_RATE_PARENT)
+ best = __clk_round_rate(parent, rate);
+ else if (parent)
+ best = __clk_get_rate(parent);
+ else
+ best = __clk_get_rate(clk);
+ goto out;
+ }
+
+ /* find the parent that can provide the fastest rate <= rate */
+ num_parents = clk->num_parents;
+ for (i = 0; i < num_parents; i++) {
+ parent = clk_get_parent_by_index(clk, i);
+ if (!parent)
+ continue;
+ if (clk->flags & CLK_SET_RATE_PARENT)
+ parent_rate = __clk_round_rate(parent, rate);
+ else
+ parent_rate = __clk_get_rate(parent);
+ if (parent_rate <= rate && parent_rate > best) {
+ best_parent = parent;
+ best = parent_rate;
+ }
+ }
+
+out:
+ if (best_parent)
+ *best_parent_p = best_parent;
+ *best_parent_rate = best;
+
+ return best;
+}
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
+
/*** clk api ***/
void __clk_unprepare(struct clk *clk)
@@ -403,7 +810,7 @@ void __clk_unprepare(struct clk *clk)
/**
* clk_unprepare - undo preparation of a clock source
- * @clk: the clk being unprepare
+ * @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
@@ -414,9 +821,12 @@ void __clk_unprepare(struct clk *clk)
*/
void clk_unprepare(struct clk *clk)
{
- mutex_lock(&prepare_lock);
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
+ clk_prepare_lock();
__clk_unprepare(clk);
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
}
EXPORT_SYMBOL_GPL(clk_unprepare);
@@ -462,9 +872,9 @@ int clk_prepare(struct clk *clk)
{
int ret;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
ret = __clk_prepare(clk);
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -475,9 +885,6 @@ static void __clk_disable(struct clk *clk)
if (!clk)
return;
- if (WARN_ON(IS_ERR(clk)))
- return;
-
if (WARN_ON(clk->enable_count == 0))
return;
@@ -506,9 +913,12 @@ void clk_disable(struct clk *clk)
{
unsigned long flags;
- spin_lock_irqsave(&enable_lock, flags);
+ if (IS_ERR_OR_NULL(clk))
+ return;
+
+ flags = clk_enable_lock();
__clk_disable(clk);
- spin_unlock_irqrestore(&enable_lock, flags);
+ clk_enable_unlock(flags);
}
EXPORT_SYMBOL_GPL(clk_disable);
@@ -559,9 +969,9 @@ int clk_enable(struct clk *clk)
unsigned long flags;
int ret;
- spin_lock_irqsave(&enable_lock, flags);
+ flags = clk_enable_lock();
ret = __clk_enable(clk);
- spin_unlock_irqrestore(&enable_lock, flags);
+ clk_enable_unlock(flags);
return ret;
}
@@ -570,28 +980,33 @@ EXPORT_SYMBOL_GPL(clk_enable);
/**
* __clk_round_rate - round the given rate for a clk
* @clk: round the rate of this clock
+ * @rate: the rate which is to be rounded
*
* Caller must hold prepare_lock. Useful for clk_ops such as .set_rate
*/
unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
{
unsigned long parent_rate = 0;
+ struct clk *parent;
if (!clk)
return 0;
- if (!clk->ops->round_rate) {
- if (clk->flags & CLK_SET_RATE_PARENT)
- return __clk_round_rate(clk->parent, rate);
- else
- return clk->rate;
- }
-
- if (clk->parent)
- parent_rate = clk->parent->rate;
-
- return clk->ops->round_rate(clk->hw, rate, &parent_rate);
+ parent = clk->parent;
+ if (parent)
+ parent_rate = parent->rate;
+
+ if (clk->ops->determine_rate)
+ return clk->ops->determine_rate(clk->hw, rate, &parent_rate,
+ &parent);
+ else if (clk->ops->round_rate)
+ return clk->ops->round_rate(clk->hw, rate, &parent_rate);
+ else if (clk->flags & CLK_SET_RATE_PARENT)
+ return __clk_round_rate(clk->parent, rate);
+ else
+ return clk->rate;
}
+EXPORT_SYMBOL_GPL(__clk_round_rate);
/**
* clk_round_rate - round the given rate for a clk
@@ -606,9 +1021,9 @@ long clk_round_rate(struct clk *clk, unsigned long rate)
{
unsigned long ret;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
ret = __clk_round_rate(clk, rate);
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -651,13 +1066,73 @@ static int __clk_notify(struct clk *clk, unsigned long msg,
}
/**
+ * __clk_recalc_accuracies
+ * @clk: 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 it's
+ * parent.
+ *
+ * Caller must hold prepare_lock.
+ */
+static void __clk_recalc_accuracies(struct clk *clk)
+{
+ unsigned long parent_accuracy = 0;
+ struct clk *child;
+
+ if (clk->parent)
+ parent_accuracy = clk->parent->accuracy;
+
+ if (clk->ops->recalc_accuracy)
+ clk->accuracy = clk->ops->recalc_accuracy(clk->hw,
+ parent_accuracy);
+ else
+ clk->accuracy = parent_accuracy;
+
+ hlist_for_each_entry(child, &clk->children, child_node)
+ __clk_recalc_accuracies(child);
+}
+
+/**
+ * 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)
+{
+ unsigned long accuracy;
+
+ clk_prepare_lock();
+ if (clk && (clk->flags & CLK_GET_ACCURACY_NOCACHE))
+ __clk_recalc_accuracies(clk);
+
+ accuracy = __clk_get_accuracy(clk);
+ clk_prepare_unlock();
+
+ return accuracy;
+}
+EXPORT_SYMBOL_GPL(clk_get_accuracy);
+
+static unsigned long clk_recalc(struct clk *clk, unsigned long parent_rate)
+{
+ if (clk->ops->recalc_rate)
+ return clk->ops->recalc_rate(clk->hw, parent_rate);
+ return parent_rate;
+}
+
+/**
* __clk_recalc_rates
* @clk: first clk in the subtree
* @msg: notification type (see include/linux/clk.h)
*
* Walks the subtree of clks starting with clk and recalculates rates as it
* goes. Note that if a clk does not implement the .recalc_rate callback then
- * it is assumed that the clock will take on the rate of it's parent.
+ * 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.
@@ -668,7 +1143,6 @@ static void __clk_recalc_rates(struct clk *clk, unsigned long msg)
{
unsigned long old_rate;
unsigned long parent_rate = 0;
- struct hlist_node *tmp;
struct clk *child;
old_rate = clk->rate;
@@ -676,10 +1150,7 @@ static void __clk_recalc_rates(struct clk *clk, unsigned long msg)
if (clk->parent)
parent_rate = clk->parent->rate;
- if (clk->ops->recalc_rate)
- clk->rate = clk->ops->recalc_rate(clk->hw, parent_rate);
- else
- clk->rate = parent_rate;
+ clk->rate = clk_recalc(clk, parent_rate);
/*
* ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
@@ -688,7 +1159,7 @@ static void __clk_recalc_rates(struct clk *clk, unsigned long msg)
if (clk->notifier_count && msg)
__clk_notify(clk, msg, old_rate, clk->rate);
- hlist_for_each_entry(child, tmp, &clk->children, child_node)
+ hlist_for_each_entry(child, &clk->children, child_node)
__clk_recalc_rates(child, msg);
}
@@ -704,18 +1175,150 @@ unsigned long clk_get_rate(struct clk *clk)
{
unsigned long rate;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
if (clk && (clk->flags & CLK_GET_RATE_NOCACHE))
__clk_recalc_rates(clk, 0);
rate = __clk_get_rate(clk);
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return rate;
}
EXPORT_SYMBOL_GPL(clk_get_rate);
+static int clk_fetch_parent_index(struct clk *clk, struct clk *parent)
+{
+ int i;
+
+ if (!clk->parents) {
+ clk->parents = kcalloc(clk->num_parents,
+ sizeof(struct clk *), GFP_KERNEL);
+ if (!clk->parents)
+ return -ENOMEM;
+ }
+
+ /*
+ * find index of new parent clock using cached parent ptrs,
+ * or if not yet cached, use string name comparison and cache
+ * them now to avoid future calls to __clk_lookup.
+ */
+ for (i = 0; i < clk->num_parents; i++) {
+ if (clk->parents[i] == parent)
+ return i;
+
+ if (clk->parents[i])
+ continue;
+
+ if (!strcmp(clk->parent_names[i], parent->name)) {
+ clk->parents[i] = __clk_lookup(parent->name);
+ return i;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static void clk_reparent(struct clk *clk, struct clk *new_parent)
+{
+ hlist_del(&clk->child_node);
+
+ if (new_parent) {
+ /* avoid duplicate POST_RATE_CHANGE notifications */
+ if (new_parent->new_child == clk)
+ new_parent->new_child = NULL;
+
+ hlist_add_head(&clk->child_node, &new_parent->children);
+ } else {
+ hlist_add_head(&clk->child_node, &clk_orphan_list);
+ }
+
+ clk->parent = new_parent;
+}
+
+static struct clk *__clk_set_parent_before(struct clk *clk, struct clk *parent)
+{
+ unsigned long flags;
+ struct clk *old_parent = clk->parent;
+
+ /*
+ * 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.
+ */
+ if (clk->prepare_count) {
+ __clk_prepare(parent);
+ clk_enable(parent);
+ clk_enable(clk);
+ }
+
+ /* update the clk tree topology */
+ flags = clk_enable_lock();
+ clk_reparent(clk, parent);
+ clk_enable_unlock(flags);
+
+ return old_parent;
+}
+
+static void __clk_set_parent_after(struct clk *clk, struct clk *parent,
+ struct clk *old_parent)
+{
+ /*
+ * Finish the migration of prepare state and undo the changes done
+ * for preventing a race with clk_enable().
+ */
+ if (clk->prepare_count) {
+ clk_disable(clk);
+ clk_disable(old_parent);
+ __clk_unprepare(old_parent);
+ }
+
+ /* update debugfs with new clk tree topology */
+ clk_debug_reparent(clk, parent);
+}
+
+static int __clk_set_parent(struct clk *clk, struct clk *parent, u8 p_index)
+{
+ unsigned long flags;
+ int ret = 0;
+ struct clk *old_parent;
+
+ old_parent = __clk_set_parent_before(clk, parent);
+
+ /* change clock input source */
+ if (parent && clk->ops->set_parent)
+ ret = clk->ops->set_parent(clk->hw, p_index);
+
+ if (ret) {
+ flags = clk_enable_lock();
+ clk_reparent(clk, old_parent);
+ clk_enable_unlock(flags);
+
+ if (clk->prepare_count) {
+ clk_disable(clk);
+ clk_disable(parent);
+ __clk_unprepare(parent);
+ }
+ return ret;
+ }
+
+ __clk_set_parent_after(clk, parent, old_parent);
+
+ return 0;
+}
+
/**
* __clk_speculate_rates
* @clk: first clk in the subtree
@@ -728,32 +1331,31 @@ EXPORT_SYMBOL_GPL(clk_get_rate);
* pre-rate change notifications and returns early if no clks in the
* subtree have subscribed to the notifications. Note that if a clk does not
* implement the .recalc_rate callback then it is assumed that the clock will
- * take on the rate of it's parent.
+ * take on the rate of its parent.
*
* Caller must hold prepare_lock.
*/
static int __clk_speculate_rates(struct clk *clk, unsigned long parent_rate)
{
- struct hlist_node *tmp;
struct clk *child;
unsigned long new_rate;
int ret = NOTIFY_DONE;
- if (clk->ops->recalc_rate)
- new_rate = clk->ops->recalc_rate(clk->hw, parent_rate);
- else
- new_rate = parent_rate;
+ new_rate = clk_recalc(clk, parent_rate);
- /* abort the rate change if a driver returns NOTIFY_BAD */
+ /* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */
if (clk->notifier_count)
ret = __clk_notify(clk, PRE_RATE_CHANGE, clk->rate, new_rate);
- if (ret == NOTIFY_BAD)
+ if (ret & NOTIFY_STOP_MASK) {
+ pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n",
+ __func__, clk->name, ret);
goto out;
+ }
- hlist_for_each_entry(child, tmp, &clk->children, child_node) {
+ hlist_for_each_entry(child, &clk->children, child_node) {
ret = __clk_speculate_rates(child, new_rate);
- if (ret == NOTIFY_BAD)
+ if (ret & NOTIFY_STOP_MASK)
break;
}
@@ -761,19 +1363,22 @@ out:
return ret;
}
-static void clk_calc_subtree(struct clk *clk, unsigned long new_rate)
+static void clk_calc_subtree(struct clk *clk, unsigned long new_rate,
+ struct clk *new_parent, u8 p_index)
{
struct clk *child;
- struct hlist_node *tmp;
clk->new_rate = new_rate;
-
- hlist_for_each_entry(child, tmp, &clk->children, child_node) {
- if (child->ops->recalc_rate)
- child->new_rate = child->ops->recalc_rate(child->hw, new_rate);
- else
- child->new_rate = new_rate;
- clk_calc_subtree(child, child->new_rate);
+ clk->new_parent = new_parent;
+ clk->new_parent_index = p_index;
+ /* include clk in new parent's PRE_RATE_CHANGE notifications */
+ clk->new_child = NULL;
+ if (new_parent && new_parent != clk->parent)
+ new_parent->new_child = clk;
+
+ hlist_for_each_entry(child, &clk->children, child_node) {
+ child->new_rate = clk_recalc(child, new_rate);
+ clk_calc_subtree(child, child->new_rate, NULL, 0);
}
}
@@ -784,50 +1389,63 @@ static void clk_calc_subtree(struct clk *clk, unsigned long new_rate)
static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate)
{
struct clk *top = clk;
+ struct clk *old_parent, *parent;
unsigned long best_parent_rate = 0;
unsigned long new_rate;
+ int p_index = 0;
/* sanity */
if (IS_ERR_OR_NULL(clk))
return NULL;
/* save parent rate, if it exists */
- if (clk->parent)
- best_parent_rate = clk->parent->rate;
-
- /* never propagate up to the parent */
- if (!(clk->flags & CLK_SET_RATE_PARENT)) {
- if (!clk->ops->round_rate) {
- clk->new_rate = clk->rate;
- return NULL;
- }
- new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate);
+ parent = old_parent = clk->parent;
+ if (parent)
+ best_parent_rate = parent->rate;
+
+ /* find the closest rate and parent clk/rate */
+ if (clk->ops->determine_rate) {
+ new_rate = clk->ops->determine_rate(clk->hw, rate,
+ &best_parent_rate,
+ &parent);
+ } else if (clk->ops->round_rate) {
+ new_rate = clk->ops->round_rate(clk->hw, rate,
+ &best_parent_rate);
+ } else if (!parent || !(clk->flags & CLK_SET_RATE_PARENT)) {
+ /* pass-through clock without adjustable parent */
+ clk->new_rate = clk->rate;
+ return NULL;
+ } else {
+ /* pass-through clock with adjustable parent */
+ top = clk_calc_new_rates(parent, rate);
+ new_rate = parent->new_rate;
goto out;
}
- /* need clk->parent from here on out */
- if (!clk->parent) {
- pr_debug("%s: %s has NULL parent\n", __func__, clk->name);
+ /* some clocks must be gated to change parent */
+ if (parent != old_parent &&
+ (clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count) {
+ pr_debug("%s: %s not gated but wants to reparent\n",
+ __func__, clk->name);
return NULL;
}
- if (!clk->ops->round_rate) {
- top = clk_calc_new_rates(clk->parent, rate);
- new_rate = clk->parent->new_rate;
-
- goto out;
+ /* try finding the new parent index */
+ if (parent) {
+ p_index = clk_fetch_parent_index(clk, parent);
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, clk->name);
+ return NULL;
+ }
}
- new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate);
-
- if (best_parent_rate != clk->parent->rate) {
- top = clk_calc_new_rates(clk->parent, best_parent_rate);
-
- goto out;
- }
+ if ((clk->flags & CLK_SET_RATE_PARENT) && parent &&
+ best_parent_rate != parent->rate)
+ top = clk_calc_new_rates(parent, best_parent_rate);
out:
- clk_calc_subtree(clk, new_rate);
+ clk_calc_subtree(clk, new_rate, parent, p_index);
return top;
}
@@ -839,23 +1457,32 @@ out:
*/
static struct clk *clk_propagate_rate_change(struct clk *clk, unsigned long event)
{
- struct hlist_node *tmp;
- struct clk *child, *fail_clk = NULL;
+ struct clk *child, *tmp_clk, *fail_clk = NULL;
int ret = NOTIFY_DONE;
if (clk->rate == clk->new_rate)
- return 0;
+ return NULL;
if (clk->notifier_count) {
ret = __clk_notify(clk, event, clk->rate, clk->new_rate);
- if (ret == NOTIFY_BAD)
+ if (ret & NOTIFY_STOP_MASK)
fail_clk = clk;
}
- hlist_for_each_entry(child, tmp, &clk->children, child_node) {
- clk = clk_propagate_rate_change(child, event);
- if (clk)
- fail_clk = clk;
+ hlist_for_each_entry(child, &clk->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != clk)
+ 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 clk->children yet */
+ if (clk->new_child) {
+ tmp_clk = clk_propagate_rate_change(clk->new_child, event);
+ if (tmp_clk)
+ fail_clk = tmp_clk;
}
return fail_clk;
@@ -870,26 +1497,49 @@ static void clk_change_rate(struct clk *clk)
struct clk *child;
unsigned long old_rate;
unsigned long best_parent_rate = 0;
- struct hlist_node *tmp;
+ bool skip_set_rate = false;
+ struct clk *old_parent;
old_rate = clk->rate;
- if (clk->parent)
+ if (clk->new_parent)
+ best_parent_rate = clk->new_parent->rate;
+ else if (clk->parent)
best_parent_rate = clk->parent->rate;
- if (clk->ops->set_rate)
+ if (clk->new_parent && clk->new_parent != clk->parent) {
+ old_parent = __clk_set_parent_before(clk, clk->new_parent);
+
+ if (clk->ops->set_rate_and_parent) {
+ skip_set_rate = true;
+ clk->ops->set_rate_and_parent(clk->hw, clk->new_rate,
+ best_parent_rate,
+ clk->new_parent_index);
+ } else if (clk->ops->set_parent) {
+ clk->ops->set_parent(clk->hw, clk->new_parent_index);
+ }
+
+ __clk_set_parent_after(clk, clk->new_parent, old_parent);
+ }
+
+ if (!skip_set_rate && clk->ops->set_rate)
clk->ops->set_rate(clk->hw, clk->new_rate, best_parent_rate);
- if (clk->ops->recalc_rate)
- clk->rate = clk->ops->recalc_rate(clk->hw, best_parent_rate);
- else
- clk->rate = best_parent_rate;
+ clk->rate = clk_recalc(clk, best_parent_rate);
if (clk->notifier_count && old_rate != clk->rate)
__clk_notify(clk, POST_RATE_CHANGE, old_rate, clk->rate);
- hlist_for_each_entry(child, tmp, &clk->children, child_node)
+ hlist_for_each_entry(child, &clk->children, child_node) {
+ /* Skip children who will be reparented to another clock */
+ if (child->new_parent && child->new_parent != clk)
+ continue;
clk_change_rate(child);
+ }
+
+ /* handle the new child who might not be in clk->children yet */
+ if (clk->new_child)
+ clk_change_rate(clk->new_child);
}
/**
@@ -904,7 +1554,7 @@ static void clk_change_rate(struct clk *clk)
* 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 it's rate. Upward propagation will continue
+ * 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.
*
@@ -918,11 +1568,14 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
struct clk *top, *fail_clk;
int ret = 0;
+ if (!clk)
+ return 0;
+
/* prevent racing with updates to the clock topology */
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
/* bail early if nothing to do */
- if (rate == clk->rate)
+ if (rate == clk_get_rate(clk))
goto out;
if ((clk->flags & CLK_SET_RATE_GATE) && clk->prepare_count) {
@@ -940,7 +1593,7 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
/* notify that we are about to change rates */
fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
if (fail_clk) {
- pr_warn("%s: failed to set %s rate\n", __func__,
+ pr_debug("%s: failed to set %s rate\n", __func__,
fail_clk->name);
clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
ret = -EBUSY;
@@ -950,11 +1603,8 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
/* change the rates */
clk_change_rate(top);
- mutex_unlock(&prepare_lock);
-
- return 0;
out:
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -970,9 +1620,9 @@ struct clk *clk_get_parent(struct clk *clk)
{
struct clk *parent;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
parent = __clk_get_parent(clk);
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return parent;
}
@@ -1021,16 +1671,10 @@ static struct clk *__clk_init_parent(struct clk *clk)
if (!clk->parents)
clk->parents =
- kzalloc((sizeof(struct clk*) * clk->num_parents),
+ kcalloc(clk->num_parents, sizeof(struct clk *),
GFP_KERNEL);
- if (!clk->parents)
- ret = __clk_lookup(clk->parent_names[index]);
- else if (!clk->parents[index])
- ret = clk->parents[index] =
- __clk_lookup(clk->parent_names[index]);
- else
- ret = clk->parents[index];
+ ret = clk_get_parent_by_index(clk, index);
out:
return ret;
@@ -1038,158 +1682,86 @@ out:
void __clk_reparent(struct clk *clk, struct clk *new_parent)
{
-#ifdef CONFIG_COMMON_CLK_DEBUG
- struct dentry *d;
- struct dentry *new_parent_d;
-#endif
-
- if (!clk || !new_parent)
- return;
-
- hlist_del(&clk->child_node);
-
- if (new_parent)
- hlist_add_head(&clk->child_node, &new_parent->children);
- else
- hlist_add_head(&clk->child_node, &clk_orphan_list);
-
-#ifdef CONFIG_COMMON_CLK_DEBUG
- if (!inited)
- goto out;
-
- if (new_parent)
- new_parent_d = new_parent->dentry;
- else
- new_parent_d = orphandir;
-
- d = debugfs_rename(clk->dentry->d_parent, clk->dentry,
- new_parent_d, clk->name);
- if (d)
- clk->dentry = d;
- else
- pr_debug("%s: failed to rename debugfs entry for %s\n",
- __func__, clk->name);
-out:
-#endif
-
- clk->parent = new_parent;
-
+ clk_reparent(clk, new_parent);
+ clk_debug_reparent(clk, new_parent);
+ __clk_recalc_accuracies(clk);
__clk_recalc_rates(clk, POST_RATE_CHANGE);
}
-static int __clk_set_parent(struct clk *clk, struct clk *parent)
-{
- struct clk *old_parent;
- unsigned long flags;
- int ret = -EINVAL;
- u8 i;
-
- old_parent = clk->parent;
-
- if (!clk->parents)
- clk->parents = kzalloc((sizeof(struct clk*) * clk->num_parents),
- GFP_KERNEL);
-
- /*
- * find index of new parent clock using cached parent ptrs,
- * or if not yet cached, use string name comparison and cache
- * them now to avoid future calls to __clk_lookup.
- */
- for (i = 0; i < clk->num_parents; i++) {
- if (clk->parents && clk->parents[i] == parent)
- break;
- else if (!strcmp(clk->parent_names[i], parent->name)) {
- if (clk->parents)
- clk->parents[i] = __clk_lookup(parent->name);
- break;
- }
- }
-
- if (i == clk->num_parents) {
- pr_debug("%s: clock %s is not a possible parent of clock %s\n",
- __func__, parent->name, clk->name);
- goto out;
- }
-
- /* migrate prepare and enable */
- if (clk->prepare_count)
- __clk_prepare(parent);
-
- /* FIXME replace with clk_is_enabled(clk) someday */
- spin_lock_irqsave(&enable_lock, flags);
- if (clk->enable_count)
- __clk_enable(parent);
- spin_unlock_irqrestore(&enable_lock, flags);
-
- /* change clock input source */
- ret = clk->ops->set_parent(clk->hw, i);
-
- /* clean up old prepare and enable */
- spin_lock_irqsave(&enable_lock, flags);
- if (clk->enable_count)
- __clk_disable(old_parent);
- spin_unlock_irqrestore(&enable_lock, flags);
-
- if (clk->prepare_count)
- __clk_unprepare(old_parent);
-
-out:
- return ret;
-}
-
/**
* clk_set_parent - switch the parent of a mux clk
* @clk: the mux clk whose input we are switching
* @parent: the new input to clk
*
- * Re-parent clk to use parent as it's new input source. If clk has the
- * CLK_SET_PARENT_GATE flag set then clk must be gated for this
- * operation to succeed. After successfully changing clk's parent
- * clk_set_parent will update the clk topology, sysfs topology and
- * propagate rate recalculation via __clk_recalc_rates. Returns 0 on
- * success, -EERROR otherwise.
+ * 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 = 0;
+ int p_index = 0;
+ unsigned long p_rate = 0;
- if (!clk || !clk->ops)
- return -EINVAL;
+ if (!clk)
+ return 0;
- if (!clk->ops->set_parent)
+ /* verify ops for for multi-parent clks */
+ if ((clk->num_parents > 1) && (!clk->ops->set_parent))
return -ENOSYS;
/* prevent racing with updates to the clock topology */
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
if (clk->parent == parent)
goto out;
+ /* check that we are allowed to re-parent if the clock is in use */
+ if ((clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* try finding the new parent index */
+ if (parent) {
+ p_index = clk_fetch_parent_index(clk, parent);
+ p_rate = parent->rate;
+ if (p_index < 0) {
+ pr_debug("%s: clk %s can not be parent of clk %s\n",
+ __func__, parent->name, clk->name);
+ ret = p_index;
+ goto out;
+ }
+ }
+
/* propagate PRE_RATE_CHANGE notifications */
- if (clk->notifier_count)
- ret = __clk_speculate_rates(clk, parent->rate);
+ ret = __clk_speculate_rates(clk, p_rate);
/* abort if a driver objects */
- if (ret == NOTIFY_STOP)
+ if (ret & NOTIFY_STOP_MASK)
goto out;
- /* only re-parent if the clock is not in use */
- if ((clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count)
- ret = -EBUSY;
- else
- ret = __clk_set_parent(clk, parent);
+ /* do the re-parent */
+ ret = __clk_set_parent(clk, parent, p_index);
- /* propagate ABORT_RATE_CHANGE if .set_parent failed */
+ /* propagate rate an accuracy recalculation accordingly */
if (ret) {
__clk_recalc_rates(clk, ABORT_RATE_CHANGE);
- goto out;
+ } else {
+ __clk_recalc_rates(clk, POST_RATE_CHANGE);
+ __clk_recalc_accuracies(clk);
}
- /* propagate rate recalculation downstream */
- __clk_reparent(clk, parent);
-
out:
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -1207,12 +1779,12 @@ int __clk_init(struct device *dev, struct clk *clk)
{
int i, ret = 0;
struct clk *orphan;
- struct hlist_node *tmp, *tmp2;
+ struct hlist_node *tmp2;
if (!clk)
return -EINVAL;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
/* check to see if a clock with this name is already registered */
if (__clk_lookup(clk->name)) {
@@ -1224,8 +1796,9 @@ int __clk_init(struct device *dev, struct clk *clk)
/* check that clk_ops are sane. See Documentation/clk.txt */
if (clk->ops->set_rate &&
- !(clk->ops->round_rate && clk->ops->recalc_rate)) {
- pr_warning("%s: %s must implement .round_rate & .recalc_rate\n",
+ !((clk->ops->round_rate || clk->ops->determine_rate) &&
+ clk->ops->recalc_rate)) {
+ pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
__func__, clk->name);
ret = -EINVAL;
goto out;
@@ -1238,6 +1811,14 @@ int __clk_init(struct device *dev, struct clk *clk)
goto out;
}
+ if (clk->ops->set_rate_and_parent &&
+ !(clk->ops->set_parent && clk->ops->set_rate)) {
+ pr_warn("%s: %s must implement .set_parent & .set_rate\n",
+ __func__, clk->name);
+ ret = -EINVAL;
+ goto out;
+ }
+
/* throw a WARN if any entries in parent_names are NULL */
for (i = 0; i < clk->num_parents; i++)
WARN(!clk->parent_names[i],
@@ -1255,8 +1836,8 @@ int __clk_init(struct device *dev, struct clk *clk)
* for clock drivers to statically initialize clk->parents.
*/
if (clk->num_parents > 1 && !clk->parents) {
- clk->parents = kzalloc((sizeof(struct clk*) * clk->num_parents),
- GFP_KERNEL);
+ clk->parents = kcalloc(clk->num_parents, sizeof(struct clk *),
+ GFP_KERNEL);
/*
* __clk_lookup returns NULL for parents that have not been
* clk_init'd; thus any access to clk->parents[] must check
@@ -1290,6 +1871,21 @@ int __clk_init(struct device *dev, struct clk *clk)
hlist_add_head(&clk->child_node, &clk_orphan_list);
/*
+ * 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 (clk->ops->recalc_accuracy)
+ clk->accuracy = clk->ops->recalc_accuracy(clk->hw,
+ __clk_get_accuracy(clk->parent));
+ else if (clk->parent)
+ clk->accuracy = clk->parent->accuracy;
+ else
+ clk->accuracy = 0;
+
+ /*
* 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)
@@ -1303,12 +1899,13 @@ int __clk_init(struct device *dev, struct clk *clk)
else
clk->rate = 0;
+ clk_debug_register(clk);
/*
* walk the list of orphan clocks and reparent any that are children of
* this clock
*/
- hlist_for_each_entry_safe(orphan, tmp, tmp2, &clk_orphan_list, child_node) {
- if (orphan->ops->get_parent) {
+ hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
+ if (orphan->num_parents && orphan->ops->get_parent) {
i = orphan->ops->get_parent(orphan->hw);
if (!strcmp(clk->name, orphan->parent_names[i]))
__clk_reparent(orphan, clk);
@@ -1328,15 +1925,14 @@ int __clk_init(struct device *dev, struct clk *clk)
* The .init callback is not used by any of the basic clock types, but
* exists for weird hardware that must perform initialization magic.
* Please consider other ways of solving initialization problems before
- * using this callback, as it's use is discouraged.
+ * using this callback, as its use is discouraged.
*/
if (clk->ops->init)
clk->ops->init(clk->hw);
- clk_debug_register(clk);
-
+ kref_init(&clk->ref);
out:
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -1355,7 +1951,7 @@ out:
* very large numbers of clocks that need to be statically initialized. It is
* a layering violation to include clk-private.h from any code which implements
* a clock's .ops; as such any statically initialized clock data MUST be in a
- * separate C file from the logic that implements it's operations. Returns 0
+ * separate C file from the logic that implements its operations. Returns 0
* on success, otherwise an error code.
*/
struct clk *__clk_register(struct device *dev, struct clk_hw *hw)
@@ -1370,6 +1966,10 @@ struct clk *__clk_register(struct device *dev, struct clk_hw *hw)
clk->flags = hw->init->flags;
clk->parent_names = hw->init->parent_names;
clk->num_parents = hw->init->num_parents;
+ if (dev && dev->driver)
+ clk->owner = dev->driver->owner;
+ else
+ clk->owner = NULL;
ret = __clk_init(dev, clk);
if (ret)
@@ -1379,9 +1979,28 @@ struct clk *__clk_register(struct device *dev, struct clk_hw *hw)
}
EXPORT_SYMBOL_GPL(__clk_register);
-static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *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 conjuction 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 *clk;
+
+ clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+ if (!clk) {
+ pr_err("%s: could not allocate clk\n", __func__);
+ ret = -ENOMEM;
+ goto fail_out;
+ }
clk->name = kstrdup(hw->init->name, GFP_KERNEL);
if (!clk->name) {
@@ -1390,14 +2009,16 @@ static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *clk)
goto fail_name;
}
clk->ops = hw->init->ops;
+ if (dev && dev->driver)
+ clk->owner = dev->driver->owner;
clk->hw = hw;
clk->flags = hw->init->flags;
clk->num_parents = hw->init->num_parents;
hw->clk = clk;
/* allocate local copy in case parent_names is __initdata */
- clk->parent_names = kzalloc((sizeof(char*) * clk->num_parents),
- GFP_KERNEL);
+ clk->parent_names = kcalloc(clk->num_parents, sizeof(char *),
+ GFP_KERNEL);
if (!clk->parent_names) {
pr_err("%s: could not allocate clk->parent_names\n", __func__);
@@ -1419,7 +2040,7 @@ static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *clk)
ret = __clk_init(dev, clk);
if (!ret)
- return 0;
+ return clk;
fail_parent_names_copy:
while (--i >= 0)
@@ -1428,54 +2049,116 @@ fail_parent_names_copy:
fail_parent_names:
kfree(clk->name);
fail_name:
- return ret;
+ kfree(clk);
+fail_out:
+ return ERR_PTR(ret);
}
+EXPORT_SYMBOL_GPL(clk_register);
-/**
- * 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 conjuction 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.
+/*
+ * Free memory allocated for a clock.
+ * Caller must hold prepare_lock.
*/
-struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+static void __clk_release(struct kref *ref)
{
- int ret;
- struct clk *clk;
+ struct clk *clk = container_of(ref, struct clk, ref);
+ int i = clk->num_parents;
- clk = kzalloc(sizeof(*clk), GFP_KERNEL);
- if (!clk) {
- pr_err("%s: could not allocate clk\n", __func__);
- ret = -ENOMEM;
- goto fail_out;
- }
-
- ret = _clk_register(dev, hw, clk);
- if (!ret)
- return clk;
+ kfree(clk->parents);
+ while (--i >= 0)
+ kfree(clk->parent_names[i]);
+ kfree(clk->parent_names);
+ kfree(clk->name);
kfree(clk);
-fail_out:
- return ERR_PTR(ret);
}
-EXPORT_SYMBOL_GPL(clk_register);
+
+/*
+ * 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
- *
- * Currently unimplemented.
*/
-void clk_unregister(struct clk *clk) {}
+void clk_unregister(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_prepare_lock();
+
+ if (clk->ops == &clk_nodrv_ops) {
+ pr_err("%s: unregistered clock: %s\n", __func__, clk->name);
+ goto out;
+ }
+ /*
+ * Assign empty clock ops for consumers that might still hold
+ * a reference to this clock.
+ */
+ flags = clk_enable_lock();
+ clk->ops = &clk_nodrv_ops;
+ clk_enable_unlock(flags);
+
+ if (!hlist_empty(&clk->children)) {
+ struct clk *child;
+ struct hlist_node *t;
+
+ /* Reparent all children to the orphan list. */
+ hlist_for_each_entry_safe(child, t, &clk->children, child_node)
+ clk_set_parent(child, NULL);
+ }
+
+ clk_debug_unregister(clk);
+
+ hlist_del_init(&clk->child_node);
+
+ if (clk->prepare_count)
+ pr_warn("%s: unregistering prepared clock: %s\n",
+ __func__, clk->name);
+
+ kref_put(&clk->ref, __clk_release);
+out:
+ clk_prepare_unlock();
+}
EXPORT_SYMBOL_GPL(clk_unregister);
static void devm_clk_release(struct device *dev, void *res)
{
- clk_unregister(res);
+ clk_unregister(*(struct clk **)res);
}
/**
@@ -1490,18 +2173,18 @@ static void devm_clk_release(struct device *dev, void *res)
struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw)
{
struct clk *clk;
- int ret;
+ struct clk **clkp;
- clk = devres_alloc(devm_clk_release, sizeof(*clk), GFP_KERNEL);
- if (!clk)
+ clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL);
+ if (!clkp)
return ERR_PTR(-ENOMEM);
- ret = _clk_register(dev, hw, clk);
- if (!ret) {
- devres_add(dev, clk);
+ clk = clk_register(dev, hw);
+ if (!IS_ERR(clk)) {
+ *clkp = clk;
+ devres_add(dev, clkp);
} else {
- devres_free(clk);
- clk = ERR_PTR(ret);
+ devres_free(clkp);
}
return clk;
@@ -1530,6 +2213,32 @@ void devm_clk_unregister(struct device *dev, struct clk *clk)
}
EXPORT_SYMBOL_GPL(devm_clk_unregister);
+/*
+ * clkdev helpers
+ */
+int __clk_get(struct clk *clk)
+{
+ if (clk) {
+ if (!try_module_get(clk->owner))
+ return 0;
+
+ kref_get(&clk->ref);
+ }
+ return 1;
+}
+
+void __clk_put(struct clk *clk)
+{
+ if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
+ return;
+
+ clk_prepare_lock();
+ kref_put(&clk->ref, __clk_release);
+ clk_prepare_unlock();
+
+ module_put(clk->owner);
+}
+
/*** clk rate change notifiers ***/
/**
@@ -1543,20 +2252,11 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister);
* re-enter into the clk framework by calling any top-level clk APIs;
* this will cause a nested prepare_lock mutex.
*
- * Pre-change notifier callbacks will be passed the current, pre-change
- * rate of the clk via struct clk_notifier_data.old_rate. The new,
- * post-change rate of the clk is passed via struct
- * clk_notifier_data.new_rate.
- *
- * Post-change notifiers will pass the now-current, post-change rate of
- * the clk in both struct clk_notifier_data.old_rate and struct
+ * In all notification cases 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.
*
- * Abort-change notifiers are effectively the opposite of pre-change
- * notifiers: the original pre-change clk rate is passed in via struct
- * clk_notifier_data.new_rate and the failed post-change rate is passed
- * in via struct clk_notifier_data.old_rate.
- *
* clk_notifier_register() must be called from non-atomic context.
* Returns -EINVAL if called with null arguments, -ENOMEM upon
* allocation failure; otherwise, passes along the return value of
@@ -1570,7 +2270,7 @@ int clk_notifier_register(struct clk *clk, struct notifier_block *nb)
if (!clk || !nb)
return -EINVAL;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
/* search the list of notifiers for this clk */
list_for_each_entry(cn, &clk_notifier_list, node)
@@ -1594,7 +2294,7 @@ int clk_notifier_register(struct clk *clk, struct notifier_block *nb)
clk->notifier_count++;
out:
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -1619,7 +2319,7 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
if (!clk || !nb)
return -EINVAL;
- mutex_lock(&prepare_lock);
+ clk_prepare_lock();
list_for_each_entry(cn, &clk_notifier_list, node)
if (cn->clk == clk)
@@ -1633,6 +2333,7 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
/* 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);
}
@@ -1640,7 +2341,7 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
ret = -ENOENT;
}
- mutex_unlock(&prepare_lock);
+ clk_prepare_unlock();
return ret;
}
@@ -1663,8 +2364,22 @@ struct of_clk_provider {
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_lock);
+static DEFINE_MUTEX(of_clk_mutex);
+
+/* of_clk_provider list locking helpers */
+void of_clk_lock(void)
+{
+ mutex_lock(&of_clk_mutex);
+}
+
+void of_clk_unlock(void)
+{
+ mutex_unlock(&of_clk_mutex);
+}
struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
void *data)
@@ -1708,9 +2423,9 @@ int of_clk_add_provider(struct device_node *np,
cp->data = data;
cp->get = clk_src_get;
- mutex_lock(&of_clk_lock);
+ mutex_lock(&of_clk_mutex);
list_add(&cp->link, &of_clk_providers);
- mutex_unlock(&of_clk_lock);
+ mutex_unlock(&of_clk_mutex);
pr_debug("Added clock from %s\n", np->full_name);
return 0;
@@ -1725,7 +2440,7 @@ void of_clk_del_provider(struct device_node *np)
{
struct of_clk_provider *cp;
- mutex_lock(&of_clk_lock);
+ mutex_lock(&of_clk_mutex);
list_for_each_entry(cp, &of_clk_providers, link) {
if (cp->node == np) {
list_del(&cp->link);
@@ -1734,33 +2449,52 @@ void of_clk_del_provider(struct device_node *np)
break;
}
}
- mutex_unlock(&of_clk_lock);
+ mutex_unlock(&of_clk_mutex);
}
EXPORT_SYMBOL_GPL(of_clk_del_provider);
-struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
+struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec)
{
struct of_clk_provider *provider;
- struct clk *clk = ERR_PTR(-ENOENT);
+ struct clk *clk = ERR_PTR(-EPROBE_DEFER);
/* Check if we have such a provider in our array */
- mutex_lock(&of_clk_lock);
list_for_each_entry(provider, &of_clk_providers, link) {
if (provider->node == clkspec->np)
clk = provider->get(clkspec, provider->data);
if (!IS_ERR(clk))
break;
}
- mutex_unlock(&of_clk_lock);
return clk;
}
+struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
+{
+ struct clk *clk;
+
+ mutex_lock(&of_clk_mutex);
+ clk = __of_clk_get_from_provider(clkspec);
+ mutex_unlock(&of_clk_mutex);
+
+ return clk;
+}
+
+int of_clk_get_parent_count(struct device_node *np)
+{
+ return of_count_phandle_with_args(np, "clocks", "#clock-cells");
+}
+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;
if (index < 0)
return NULL;
@@ -1770,8 +2504,22 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
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++;
+ }
+
if (of_property_read_string_index(clkspec.np, "clock-output-names",
- clkspec.args_count ? clkspec.args[0] : 0,
+ index,
&clk_name) < 0)
clk_name = clkspec.np->name;
@@ -1780,21 +2528,99 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
}
EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
+struct clock_provider {
+ of_clk_init_cb_t clk_init_cb;
+ struct device_node *np;
+ struct list_head node;
+};
+
+static LIST_HEAD(clk_provider_list);
+
+/*
+ * 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_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
+ * 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;
+
+ 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 =
+ kzalloc(sizeof(struct clock_provider), GFP_KERNEL);
+
+ parent->clk_init_cb = match->data;
+ parent->np = 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)) {
+ clk_provider->clk_init_cb(clk_provider->np);
+ list_del(&clk_provider->node);
+ 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;
- for_each_matching_node(np, matches) {
- const struct of_device_id *match = of_match_node(matches, np);
- of_clk_init_cb_t clk_init_cb = match->data;
- clk_init_cb(np);
}
}
#endif
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 12:16:45 +0000