* Standard functionality for the common clock API. See Documentation/clk.txt
*/
+#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clk/clk-conf.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/sched.h>
+#include <linux/clkdev.h>
#include "clk.h"
static HLIST_HEAD(clk_orphan_list);
static LIST_HEAD(clk_notifier_list);
-static long clk_core_get_accuracy(struct clk_core *clk);
-static unsigned long clk_core_get_rate(struct clk_core *clk);
-static int clk_core_get_phase(struct clk_core *clk);
-static bool clk_core_is_prepared(struct clk_core *clk);
-static bool clk_core_is_enabled(struct clk_core *clk);
-static struct clk_core *clk_core_lookup(const char *name);
-
/*** private data structures ***/
struct clk_core {
struct clk_core *new_parent;
struct clk_core *new_child;
unsigned long flags;
+ bool orphan;
unsigned int enable_count;
unsigned int prepare_count;
+ unsigned long min_rate;
+ unsigned long max_rate;
unsigned long accuracy;
int phase;
struct hlist_head children;
struct hlist_node child_node;
- struct hlist_node debug_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;
};
}
static unsigned long clk_enable_lock(void)
+ __acquires(enable_lock)
{
unsigned long flags;
if (!spin_trylock_irqsave(&enable_lock, flags)) {
if (enable_owner == current) {
enable_refcnt++;
+ __acquire(enable_lock);
return flags;
}
spin_lock_irqsave(&enable_lock, 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)
+ if (--enable_refcnt) {
+ __release(enable_lock);
return;
+ }
enable_owner = NULL;
spin_unlock_irqrestore(&enable_lock, flags);
}
-/*** debugfs support ***/
-
-#ifdef CONFIG_DEBUG_FS
-#include <linux/debugfs.h>
+static bool clk_core_is_prepared(struct clk_core *core)
+{
+ /*
+ * .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;
-static struct dentry *rootdir;
-static int inited = 0;
-static DEFINE_MUTEX(clk_debug_lock);
-static HLIST_HEAD(clk_debug_list);
+ return core->ops->is_prepared(core->hw);
+}
-static struct hlist_head *all_lists[] = {
- &clk_root_list,
- &clk_orphan_list,
- NULL,
-};
+static bool clk_core_is_enabled(struct clk_core *core)
+{
+ /*
+ * .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;
-static struct hlist_head *orphan_list[] = {
- &clk_orphan_list,
- NULL,
-};
+ return core->ops->is_enabled(core->hw);
+}
-static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
- int level)
+static void clk_unprepare_unused_subtree(struct clk_core *core)
{
- if (!c)
+ 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;
- seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n",
- level * 3 + 1, "",
- 30 - level * 3, c->name,
- c->enable_count, c->prepare_count, clk_core_get_rate(c),
- clk_core_get_accuracy(c), clk_core_get_phase(c));
+ if (core->flags & CLK_IGNORE_UNUSED)
+ 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);
+ }
}
-static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
- int level)
+static void clk_disable_unused_subtree(struct clk_core *core)
{
struct clk_core *child;
+ unsigned long flags;
- if (!c)
- return;
+ lockdep_assert_held(&prepare_lock);
- clk_summary_show_one(s, c, level);
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_disable_unused_subtree(child);
- hlist_for_each_entry(child, &c->children, child_node)
- clk_summary_show_subtree(s, child, level + 1);
+ 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);
}
-static int clk_summary_show(struct seq_file *s, void *data)
+static bool clk_ignore_unused;
+static int __init clk_ignore_unused_setup(char *__unused)
{
- struct clk_core *c;
- struct hlist_head **lists = (struct hlist_head **)s->private;
+ clk_ignore_unused = true;
+ return 1;
+}
+__setup("clk_ignore_unused", clk_ignore_unused_setup);
- seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n");
- seq_puts(s, "----------------------------------------------------------------------------------------\n");
+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();
- for (; *lists; lists++)
- hlist_for_each_entry(c, *lists, child_node)
- clk_summary_show_subtree(s, c, 0);
+ 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);
+/*** helper functions ***/
-static int clk_summary_open(struct inode *inode, struct file *file)
+const char *__clk_get_name(const struct clk *clk)
{
- return single_open(file, clk_summary_show, inode->i_private);
+ return !clk ? NULL : clk->core->name;
}
+EXPORT_SYMBOL_GPL(__clk_get_name);
-static const struct file_operations clk_summary_fops = {
- .open = clk_summary_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
+const char *clk_hw_get_name(const struct clk_hw *hw)
+{
+ return hw->core->name;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_name);
-static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
+struct clk_hw *__clk_get_hw(struct clk *clk)
{
- if (!c)
- return;
+ return !clk ? NULL : clk->core->hw;
+}
+EXPORT_SYMBOL_GPL(__clk_get_hw);
- /* 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, "\"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));
+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);
-static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
+struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
{
- struct clk_core *child;
+ return hw->core->parent ? hw->core->parent->hw : NULL;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_parent);
- if (!c)
- return;
+static struct clk_core *__clk_lookup_subtree(const char *name,
+ struct clk_core *core)
+{
+ struct clk_core *child;
+ struct clk_core *ret;
- clk_dump_one(s, c, level);
+ if (!strcmp(core->name, name))
+ return core;
- hlist_for_each_entry(child, &c->children, child_node) {
- seq_printf(s, ",");
- clk_dump_subtree(s, child, level + 1);
+ hlist_for_each_entry(child, &core->children, child_node) {
+ ret = __clk_lookup_subtree(name, child);
+ if (ret)
+ return ret;
}
- seq_printf(s, "}");
+ return NULL;
}
-static int clk_dump(struct seq_file *s, void *data)
+static struct clk_core *clk_core_lookup(const char *name)
{
- struct clk_core *c;
- bool first_node = true;
- struct hlist_head **lists = (struct hlist_head **)s->private;
-
- seq_printf(s, "{");
+ struct clk_core *root_clk;
+ struct clk_core *ret;
- clk_prepare_lock();
+ if (!name)
+ return NULL;
- for (; *lists; lists++) {
- hlist_for_each_entry(c, *lists, child_node) {
- if (!first_node)
- seq_puts(s, ",");
- first_node = false;
- clk_dump_subtree(s, c, 0);
- }
+ /* 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;
}
- clk_prepare_unlock();
+ /* 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;
+ }
- seq_printf(s, "}");
- return 0;
+ 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;
+ else if (!core->parents)
+ return clk_core_lookup(core->parent_names[index]);
+ else if (!core->parents[index])
+ return core->parents[index] =
+ clk_core_lookup(core->parent_names[index]);
+ else
+ return core->parents[index];
+}
-static int clk_dump_open(struct inode *inode, struct file *file)
+struct clk_hw *
+clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index)
{
- return single_open(file, clk_dump, inode->i_private);
+ 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);
-static const struct file_operations clk_dump_fops = {
- .open = clk_dump_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
+unsigned int __clk_get_enable_count(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->enable_count;
+}
-static int clk_debug_create_one(struct clk_core *clk, struct dentry *pdentry)
+static unsigned long clk_core_get_rate_nolock(struct clk_core *core)
{
- struct dentry *d;
- int ret = -ENOMEM;
+ unsigned long ret;
- if (!clk || !pdentry) {
- ret = -EINVAL;
+ if (!core) {
+ ret = 0;
goto out;
}
- d = debugfs_create_dir(clk->name, pdentry);
- if (!d)
+ ret = core->rate;
+
+ if (core->flags & CLK_IS_ROOT)
goto out;
- clk->dentry = d;
+ if (!core->parent)
+ ret = 0;
- d = debugfs_create_u32("clk_rate", S_IRUGO, clk->dentry,
- (u32 *)&clk->rate);
- if (!d)
- goto err_out;
+out:
+ return ret;
+}
- d = debugfs_create_u32("clk_accuracy", S_IRUGO, clk->dentry,
- (u32 *)&clk->accuracy);
- if (!d)
- goto err_out;
+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);
- d = debugfs_create_u32("clk_phase", S_IRUGO, clk->dentry,
- (u32 *)&clk->phase);
- if (!d)
- goto err_out;
+static unsigned long __clk_get_accuracy(struct clk_core *core)
+{
+ if (!core)
+ return 0;
- d = debugfs_create_x32("clk_flags", S_IRUGO, clk->dentry,
- (u32 *)&clk->flags);
- if (!d)
- goto err_out;
+ return core->accuracy;
+}
- d = debugfs_create_u32("clk_prepare_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->prepare_count);
- if (!d)
- goto err_out;
+unsigned long __clk_get_flags(struct clk *clk)
+{
+ return !clk ? 0 : clk->core->flags;
+}
+EXPORT_SYMBOL_GPL(__clk_get_flags);
- d = debugfs_create_u32("clk_enable_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->enable_count);
- if (!d)
- goto err_out;
+unsigned long clk_hw_get_flags(const struct clk_hw *hw)
+{
+ return hw->core->flags;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_flags);
- d = debugfs_create_u32("clk_notifier_count", S_IRUGO, clk->dentry,
- (u32 *)&clk->notifier_count);
- if (!d)
- goto err_out;
+bool clk_hw_is_prepared(const struct clk_hw *hw)
+{
+ return clk_core_is_prepared(hw->core);
+}
- if (clk->ops->debug_init) {
- ret = clk->ops->debug_init(clk->hw, clk->dentry);
- if (ret)
- goto err_out;
- }
+bool clk_hw_is_enabled(const struct clk_hw *hw)
+{
+ return clk_core_is_enabled(hw->core);
+}
- ret = 0;
- goto out;
+bool __clk_is_enabled(struct clk *clk)
+{
+ if (!clk)
+ return false;
-err_out:
- debugfs_remove_recursive(clk->dentry);
- clk->dentry = NULL;
-out:
- return ret;
+ return clk_core_is_enabled(clk->core);
}
+EXPORT_SYMBOL_GPL(__clk_is_enabled);
-/**
- * clk_debug_register - add a clk node to the debugfs clk tree
- * @clk: the clk being added to the debugfs clk tree
- *
- * Dynamically adds a clk to the debugfs clk tree if debugfs has been
- * initialized. Otherwise it bails out early since the debugfs clk tree
- * will be created lazily by clk_debug_init as part of a late_initcall.
- */
-static int clk_debug_register(struct clk_core *clk)
+static bool mux_is_better_rate(unsigned long rate, unsigned long now,
+ unsigned long best, unsigned long flags)
{
- int ret = 0;
-
- mutex_lock(&clk_debug_lock);
- hlist_add_head(&clk->debug_node, &clk_debug_list);
-
- if (!inited)
- goto unlock;
-
- ret = clk_debug_create_one(clk, rootdir);
-unlock:
- mutex_unlock(&clk_debug_lock);
+ if (flags & CLK_MUX_ROUND_CLOSEST)
+ return abs(now - rate) < abs(best - rate);
- return ret;
+ return now <= rate && now > best;
}
- /**
- * 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.
- */
-static void clk_debug_unregister(struct clk_core *clk)
+static int
+clk_mux_determine_rate_flags(struct clk_hw *hw, struct clk_rate_request *req,
+ unsigned long flags)
{
- mutex_lock(&clk_debug_lock);
- hlist_del_init(&clk->debug_node);
- debugfs_remove_recursive(clk->dentry);
- clk->dentry = NULL;
- mutex_unlock(&clk_debug_lock);
-}
+ 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;
-struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode,
- void *data, const struct file_operations *fops)
-{
- struct dentry *d = NULL;
+ /* 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);
+ }
- if (hw->core->dentry)
- d = debugfs_create_file(name, mode, hw->core->dentry, data,
- fops);
+ goto out;
+ }
- return d;
-}
-EXPORT_SYMBOL_GPL(clk_debugfs_add_file);
+ /* 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;
-/**
- * clk_debug_init - lazily create the debugfs clk tree visualization
- *
- * clks are often initialized very early during boot before memory can
- * be dynamically allocated and well before debugfs is setup.
- * clk_debug_init walks the clk tree hierarchy while holding
- * prepare_lock and creates the topology as part of a late_initcall,
- * thus insuring that clks initialized very early will still be
- * represented in the debugfs clk tree. This function should only be
- * called once at boot-time, and all other clks added dynamically will
- * be done so with clk_debug_register.
- */
-static int __init clk_debug_init(void)
-{
- struct clk_core *clk;
- struct dentry *d;
+ 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);
+ }
- rootdir = debugfs_create_dir("clk", NULL);
+ if (mux_is_better_rate(req->rate, parent_req.rate,
+ best, flags)) {
+ best_parent = parent;
+ best = parent_req.rate;
+ }
+ }
- if (!rootdir)
- return -ENOMEM;
+ if (!best_parent)
+ return -EINVAL;
- d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
- &clk_summary_fops);
- if (!d)
- return -ENOMEM;
+out:
+ if (best_parent)
+ req->best_parent_hw = best_parent->hw;
+ req->best_parent_rate = best;
+ req->rate = best;
- d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
- &clk_dump_fops);
- if (!d)
- return -ENOMEM;
+ return 0;
+}
- d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
- &orphan_list, &clk_summary_fops);
- if (!d)
- return -ENOMEM;
+struct clk *__clk_lookup(const char *name)
+{
+ struct clk_core *core = clk_core_lookup(name);
- d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
- &orphan_list, &clk_dump_fops);
- if (!d)
- return -ENOMEM;
+ return !core ? NULL : core->hw->clk;
+}
- mutex_lock(&clk_debug_lock);
- hlist_for_each_entry(clk, &clk_debug_list, debug_node)
- clk_debug_create_one(clk, rootdir);
+static void clk_core_get_boundaries(struct clk_core *core,
+ unsigned long *min_rate,
+ unsigned long *max_rate)
+{
+ struct clk *clk_user;
- inited = 1;
- mutex_unlock(&clk_debug_lock);
+ *min_rate = core->min_rate;
+ *max_rate = core->max_rate;
- return 0;
+ 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);
}
-late_initcall(clk_debug_init);
-#else
-static inline int clk_debug_register(struct clk_core *clk) { return 0; }
-static inline void clk_debug_reparent(struct clk_core *clk,
- struct clk_core *new_parent)
+
+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;
}
-static inline void clk_debug_unregister(struct clk_core *clk)
+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);
}
-#endif
+EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
-/* caller must hold prepare_lock */
-static void clk_unprepare_unused_subtree(struct clk_core *clk)
+int __clk_mux_determine_rate_closest(struct clk_hw *hw,
+ struct clk_rate_request *req)
{
- struct clk_core *child;
+ 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_unprepare(struct clk_core *core)
+{
lockdep_assert_held(&prepare_lock);
- hlist_for_each_entry(child, &clk->children, child_node)
- clk_unprepare_unused_subtree(child);
+ if (!core)
+ return;
- if (clk->prepare_count)
+ if (WARN_ON(core->prepare_count == 0))
return;
- if (clk->flags & CLK_IGNORE_UNUSED)
+ if (--core->prepare_count > 0)
return;
- if (clk_core_is_prepared(clk)) {
- trace_clk_unprepare(clk);
- if (clk->ops->unprepare_unused)
- clk->ops->unprepare_unused(clk->hw);
- else if (clk->ops->unprepare)
- clk->ops->unprepare(clk->hw);
- trace_clk_unprepare_complete(clk);
- }
+ WARN_ON(core->enable_count > 0);
+
+ trace_clk_unprepare(core);
+
+ if (core->ops->unprepare)
+ core->ops->unprepare(core->hw);
+
+ trace_clk_unprepare_complete(core);
+ clk_core_unprepare(core->parent);
+}
+
+/**
+ * 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_prepare_lock();
+ clk_core_unprepare(clk->core);
+ clk_prepare_unlock();
}
+EXPORT_SYMBOL_GPL(clk_unprepare);
-/* caller must hold prepare_lock */
-static void clk_disable_unused_subtree(struct clk_core *clk)
+static int clk_core_prepare(struct clk_core *core)
{
- struct clk_core *child;
- unsigned long flags;
+ int ret = 0;
lockdep_assert_held(&prepare_lock);
- hlist_for_each_entry(child, &clk->children, child_node)
- clk_disable_unused_subtree(child);
+ if (!core)
+ return 0;
- flags = clk_enable_lock();
+ if (core->prepare_count == 0) {
+ ret = clk_core_prepare(core->parent);
+ if (ret)
+ return ret;
- if (clk->enable_count)
- goto unlock_out;
+ trace_clk_prepare(core);
- if (clk->flags & CLK_IGNORE_UNUSED)
- goto unlock_out;
+ if (core->ops->prepare)
+ ret = core->ops->prepare(core->hw);
- /*
- * 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(clk)) {
- trace_clk_disable(clk);
- if (clk->ops->disable_unused)
- clk->ops->disable_unused(clk->hw);
- else if (clk->ops->disable)
- clk->ops->disable(clk->hw);
- trace_clk_disable_complete(clk);
+ trace_clk_prepare_complete(core);
+
+ if (ret) {
+ clk_core_unprepare(core->parent);
+ return ret;
+ }
}
-unlock_out:
- clk_enable_unlock(flags);
-}
+ core->prepare_count++;
-static bool clk_ignore_unused;
-static int __init clk_ignore_unused_setup(char *__unused)
-{
- clk_ignore_unused = true;
- return 1;
+ return 0;
}
-__setup("clk_ignore_unused", clk_ignore_unused_setup);
-static int clk_disable_unused(void)
+/**
+ * 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)
{
- struct clk_core *clk;
+ int ret;
- if (clk_ignore_unused) {
- pr_warn("clk: Not disabling unused clocks\n");
+ if (!clk)
return 0;
- }
clk_prepare_lock();
+ ret = clk_core_prepare(clk->core);
+ clk_prepare_unlock();
- hlist_for_each_entry(clk, &clk_root_list, child_node)
- clk_disable_unused_subtree(clk);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_prepare);
- hlist_for_each_entry(clk, &clk_orphan_list, child_node)
- clk_disable_unused_subtree(clk);
+static void clk_core_disable(struct clk_core *core)
+{
+ lockdep_assert_held(&enable_lock);
- hlist_for_each_entry(clk, &clk_root_list, child_node)
- clk_unprepare_unused_subtree(clk);
+ if (!core)
+ return;
- hlist_for_each_entry(clk, &clk_orphan_list, child_node)
- clk_unprepare_unused_subtree(clk);
+ if (WARN_ON(core->enable_count == 0))
+ return;
- clk_prepare_unlock();
+ if (--core->enable_count > 0)
+ return;
- return 0;
-}
-late_initcall_sync(clk_disable_unused);
+ trace_clk_disable(core);
-/*** helper functions ***/
+ if (core->ops->disable)
+ core->ops->disable(core->hw);
-const char *__clk_get_name(struct clk *clk)
-{
- return !clk ? NULL : clk->core->name;
-}
-EXPORT_SYMBOL_GPL(__clk_get_name);
+ trace_clk_disable_complete(core);
-struct clk_hw *__clk_get_hw(struct clk *clk)
-{
- return !clk ? NULL : clk->core->hw;
+ clk_core_disable(core->parent);
}
-EXPORT_SYMBOL_GPL(__clk_get_hw);
-u8 __clk_get_num_parents(struct clk *clk)
+/**
+ * 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)
{
- return !clk ? 0 : clk->core->num_parents;
-}
-EXPORT_SYMBOL_GPL(__clk_get_num_parents);
+ unsigned long flags;
-struct clk *__clk_get_parent(struct clk *clk)
-{
- if (!clk)
- return NULL;
+ if (IS_ERR_OR_NULL(clk))
+ return;
- /* TODO: Create a per-user clk and change callers to call clk_put */
- return !clk->core->parent ? NULL : clk->core->parent->hw->clk;
+ flags = clk_enable_lock();
+ clk_core_disable(clk->core);
+ clk_enable_unlock(flags);
}
-EXPORT_SYMBOL_GPL(__clk_get_parent);
+EXPORT_SYMBOL_GPL(clk_disable);
-static struct clk_core *clk_core_get_parent_by_index(struct clk_core *clk,
- u8 index)
+static int clk_core_enable(struct clk_core *core)
{
- if (!clk || index >= clk->num_parents)
- return NULL;
- else if (!clk->parents)
- return clk_core_lookup(clk->parent_names[index]);
- else if (!clk->parents[index])
- return clk->parents[index] =
- clk_core_lookup(clk->parent_names[index]);
- else
- return clk->parents[index];
-}
+ int ret = 0;
-struct clk *clk_get_parent_by_index(struct clk *clk, u8 index)
-{
- struct clk_core *parent;
+ lockdep_assert_held(&enable_lock);
- if (!clk)
- return NULL;
+ if (!core)
+ return 0;
- parent = clk_core_get_parent_by_index(clk->core, index);
+ if (WARN_ON(core->prepare_count == 0))
+ return -ESHUTDOWN;
- return !parent ? NULL : parent->hw->clk;
-}
-EXPORT_SYMBOL_GPL(clk_get_parent_by_index);
+ if (core->enable_count == 0) {
+ ret = clk_core_enable(core->parent);
-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 *clk)
-{
- unsigned long ret;
+ if (ret)
+ return ret;
- if (!clk) {
- ret = 0;
- goto out;
- }
+ trace_clk_enable(core);
- ret = clk->rate;
+ if (core->ops->enable)
+ ret = core->ops->enable(core->hw);
- if (clk->flags & CLK_IS_ROOT)
- goto out;
+ trace_clk_enable_complete(core);
- if (!clk->parent)
- ret = 0;
+ if (ret) {
+ clk_core_disable(core->parent);
+ return ret;
+ }
+ }
-out:
- return ret;
+ core->enable_count++;
+ return 0;
}
-unsigned long __clk_get_rate(struct clk *clk)
+/**
+ * clk_enable - ungate a clock
+ * @clk: the clk being ungated
+ *
+ * clk_enable must not sleep, which differentiates it from clk_prepare. In a
+ * simple case, clk_enable can be used instead of clk_prepare to ungate a clk
+ * if the operation will never sleep. One example is a SoC-internal clk which
+ * is controlled via simple register writes. In the complex case a clk ungate
+ * operation may require a fast and a slow part. It is this reason that
+ * clk_enable and clk_prepare are not mutually exclusive. In fact clk_prepare
+ * must be called before clk_enable. Returns 0 on success, -EERROR
+ * otherwise.
+ */
+int clk_enable(struct clk *clk)
{
+ unsigned long flags;
+ int ret;
+
if (!clk)
return 0;
- return clk_core_get_rate_nolock(clk->core);
+ flags = clk_enable_lock();
+ ret = clk_core_enable(clk->core);
+ clk_enable_unlock(flags);
+
+ return ret;
}
-EXPORT_SYMBOL_GPL(__clk_get_rate);
+EXPORT_SYMBOL_GPL(clk_enable);
-static unsigned long __clk_get_accuracy(struct clk_core *clk)
+static int clk_core_round_rate_nolock(struct clk_core *core,
+ struct clk_rate_request *req)
{
- if (!clk)
- return 0;
+ struct clk_core *parent;
+ long rate;
- return clk->accuracy;
-}
+ lockdep_assert_held(&prepare_lock);
-unsigned long __clk_get_flags(struct clk *clk)
-{
- return !clk ? 0 : clk->core->flags;
-}
-EXPORT_SYMBOL_GPL(__clk_get_flags);
+ if (!core)
+ return 0;
-static bool clk_core_is_prepared(struct clk_core *clk)
-{
- int ret;
+ 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;
+ }
- if (!clk)
- return false;
+ 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;
- /*
- * .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;
+ req->rate = rate;
+ } else if (core->flags & CLK_SET_RATE_PARENT) {
+ return clk_core_round_rate_nolock(parent, req);
+ } else {
+ req->rate = core->rate;
}
- ret = clk->ops->is_prepared(clk->hw);
-out:
- return !!ret;
+ return 0;
}
-bool __clk_is_prepared(struct clk *clk)
+/**
+ * __clk_determine_rate - get the closest rate actually supported by a clock
+ * @hw: determine the rate of this clock
+ * @rate: target rate
+ * @min_rate: returned rate must be greater than this rate
+ * @max_rate: returned rate must be less than this rate
+ *
+ * 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 (!clk)
- return false;
+ if (!hw) {
+ req->rate = 0;
+ return 0;
+ }
- return clk_core_is_prepared(clk->core);
+ return clk_core_round_rate_nolock(hw->core, req);
}
+EXPORT_SYMBOL_GPL(__clk_determine_rate);
-static bool clk_core_is_enabled(struct clk_core *clk)
+unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate)
{
int ret;
+ struct clk_rate_request req;
- if (!clk)
- return false;
+ clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
- /*
- * .is_enabled is only mandatory for clocks that gate
- * fall back to software usage counter if .is_enabled is missing
- */
- if (!clk->ops->is_enabled) {
- ret = clk->enable_count ? 1 : 0;
- goto out;
- }
+ ret = clk_core_round_rate_nolock(hw->core, &req);
+ if (ret)
+ return 0;
- ret = clk->ops->is_enabled(clk->hw);
-out:
- return !!ret;
+ return req.rate;
}
+EXPORT_SYMBOL_GPL(clk_hw_round_rate);
-bool __clk_is_enabled(struct clk *clk)
+/**
+ * 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 false;
+ return 0;
- return clk_core_is_enabled(clk->core);
-}
-EXPORT_SYMBOL_GPL(__clk_is_enabled);
+ clk_prepare_lock();
-static struct clk_core *__clk_lookup_subtree(const char *name,
- struct clk_core *clk)
-{
- struct clk_core *child;
- struct clk_core *ret;
+ clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
+ req.rate = rate;
- if (!strcmp(clk->name, name))
- return clk;
+ ret = clk_core_round_rate_nolock(clk->core, &req);
+ clk_prepare_unlock();
- hlist_for_each_entry(child, &clk->children, child_node) {
- ret = __clk_lookup_subtree(name, child);
- if (ret)
- return ret;
- }
+ if (ret)
+ return ret;
- return NULL;
+ return req.rate;
}
+EXPORT_SYMBOL_GPL(clk_round_rate);
-static struct clk_core *clk_core_lookup(const char *name)
+/**
+ * __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_core *root_clk;
- struct clk_core *ret;
-
- if (!name)
- return NULL;
+ struct clk_notifier *cn;
+ struct clk_notifier_data cnd;
+ int ret = NOTIFY_DONE;
- /* 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;
- }
+ cnd.old_rate = old_rate;
+ cnd.new_rate = new_rate;
- /* 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;
+ 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);
+ }
}
- return NULL;
-}
-
-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;
+ return ret;
}
-static long
-clk_mux_determine_rate_flags(struct clk_hw *hw, unsigned long rate,
- unsigned long min_rate,
- unsigned long max_rate,
- unsigned long *best_parent_rate,
- struct clk_hw **best_parent_p,
- unsigned long flags)
+/**
+ * __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)
{
- struct clk_core *core = hw->core, *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 (core->flags & CLK_SET_RATE_NO_REPARENT) {
- parent = core->parent;
- if (core->flags & CLK_SET_RATE_PARENT)
- best = __clk_determine_rate(parent ? parent->hw : NULL,
- rate, min_rate, max_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_rate = __clk_determine_rate(parent->hw, rate,
- min_rate,
- max_rate);
- else
- parent_rate = clk_core_get_rate_nolock(parent);
- if (mux_is_better_rate(rate, parent_rate, best, flags)) {
- best_parent = parent;
- best = parent_rate;
- }
- }
+ unsigned long parent_accuracy = 0;
+ struct clk_core *child;
-out:
- if (best_parent)
- *best_parent_p = best_parent->hw;
- *best_parent_rate = best;
+ lockdep_assert_held(&prepare_lock);
- return best;
-}
+ if (core->parent)
+ parent_accuracy = core->parent->accuracy;
-struct clk *__clk_lookup(const char *name)
-{
- struct clk_core *core = clk_core_lookup(name);
+ if (core->ops->recalc_accuracy)
+ core->accuracy = core->ops->recalc_accuracy(core->hw,
+ parent_accuracy);
+ else
+ core->accuracy = parent_accuracy;
- return !core ? NULL : core->hw->clk;
+ hlist_for_each_entry(child, &core->children, child_node)
+ __clk_recalc_accuracies(child);
}
-static void clk_core_get_boundaries(struct clk_core *clk,
- unsigned long *min_rate,
- unsigned long *max_rate)
+static long clk_core_get_accuracy(struct clk_core *core)
{
- struct clk *clk_user;
+ unsigned long accuracy;
- *min_rate = 0;
- *max_rate = ULONG_MAX;
+ clk_prepare_lock();
+ if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE))
+ __clk_recalc_accuracies(core);
- hlist_for_each_entry(clk_user, &clk->clks, clks_node)
- *min_rate = max(*min_rate, clk_user->min_rate);
+ accuracy = __clk_get_accuracy(core);
+ clk_prepare_unlock();
- hlist_for_each_entry(clk_user, &clk->clks, clks_node)
- *max_rate = min(*max_rate, clk_user->max_rate);
+ return accuracy;
}
-/*
- * 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.
+/**
+ * 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_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
- unsigned long min_rate,
- unsigned long max_rate,
- unsigned long *best_parent_rate,
- struct clk_hw **best_parent_p)
+long clk_get_accuracy(struct clk *clk)
{
- return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate,
- best_parent_rate,
- best_parent_p, 0);
-}
-EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
+ if (!clk)
+ return 0;
-long __clk_mux_determine_rate_closest(struct clk_hw *hw, unsigned long rate,
- unsigned long min_rate,
- unsigned long max_rate,
- unsigned long *best_parent_rate,
- struct clk_hw **best_parent_p)
-{
- return clk_mux_determine_rate_flags(hw, rate, min_rate, max_rate,
- best_parent_rate,
- best_parent_p,
- CLK_MUX_ROUND_CLOSEST);
+ return clk_core_get_accuracy(clk->core);
}
-EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
-
-/*** clk api ***/
+EXPORT_SYMBOL_GPL(clk_get_accuracy);
-static void clk_core_unprepare(struct clk_core *clk)
+static unsigned long clk_recalc(struct clk_core *core,
+ unsigned long parent_rate)
{
- if (!clk)
- return;
-
- if (WARN_ON(clk->prepare_count == 0))
- return;
-
- if (--clk->prepare_count > 0)
- return;
-
- WARN_ON(clk->enable_count > 0);
-
- trace_clk_unprepare(clk);
-
- if (clk->ops->unprepare)
- clk->ops->unprepare(clk->hw);
-
- trace_clk_unprepare_complete(clk);
- clk_core_unprepare(clk->parent);
-}
+ if (core->ops->recalc_rate)
+ return core->ops->recalc_rate(core->hw, parent_rate);
+ return parent_rate;
+}
/**
- * clk_unprepare - undo preparation of a clock source
- * @clk: the clk being unprepared
+ * __clk_recalc_rates
+ * @core: first clk in the subtree
+ * @msg: notification type (see include/linux/clk.h)
*
- * 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.
+ * 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.
*/
-void clk_unprepare(struct clk *clk)
+static void __clk_recalc_rates(struct clk_core *core, unsigned long msg)
{
- if (IS_ERR_OR_NULL(clk))
- return;
+ unsigned long old_rate;
+ unsigned long parent_rate = 0;
+ struct clk_core *child;
- clk_prepare_lock();
- clk_core_unprepare(clk->core);
- clk_prepare_unlock();
-}
-EXPORT_SYMBOL_GPL(clk_unprepare);
+ lockdep_assert_held(&prepare_lock);
-static int clk_core_prepare(struct clk_core *clk)
-{
- int ret = 0;
+ old_rate = core->rate;
- if (!clk)
- return 0;
+ if (core->parent)
+ parent_rate = core->parent->rate;
- if (clk->prepare_count == 0) {
- ret = clk_core_prepare(clk->parent);
- if (ret)
- return ret;
+ core->rate = clk_recalc(core, parent_rate);
- trace_clk_prepare(clk);
+ /*
+ * 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);
- if (clk->ops->prepare)
- ret = clk->ops->prepare(clk->hw);
+ hlist_for_each_entry(child, &core->children, child_node)
+ __clk_recalc_rates(child, msg);
+}
- trace_clk_prepare_complete(clk);
+static unsigned long clk_core_get_rate(struct clk_core *core)
+{
+ unsigned long rate;
- if (ret) {
- clk_core_unprepare(clk->parent);
- return ret;
- }
- }
+ clk_prepare_lock();
- clk->prepare_count++;
+ if (core && (core->flags & CLK_GET_RATE_NOCACHE))
+ __clk_recalc_rates(core, 0);
- return 0;
+ rate = clk_core_get_rate_nolock(core);
+ clk_prepare_unlock();
+
+ return rate;
}
/**
- * clk_prepare - prepare a clock source
- * @clk: the clk being prepared
+ * clk_get_rate - return the rate of clk
+ * @clk: the clk whose rate is being returned
*
- * 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.
+ * 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.
*/
-int clk_prepare(struct clk *clk)
+unsigned long clk_get_rate(struct clk *clk)
{
- int ret;
-
if (!clk)
return 0;
- clk_prepare_lock();
- ret = clk_core_prepare(clk->core);
- clk_prepare_unlock();
-
- return ret;
+ return clk_core_get_rate(clk->core);
}
-EXPORT_SYMBOL_GPL(clk_prepare);
+EXPORT_SYMBOL_GPL(clk_get_rate);
-static void clk_core_disable(struct clk_core *clk)
+static int clk_fetch_parent_index(struct clk_core *core,
+ struct clk_core *parent)
{
- if (!clk)
- return;
-
- if (WARN_ON(clk->enable_count == 0))
- return;
-
- if (--clk->enable_count > 0)
- return;
-
- trace_clk_disable(clk);
+ int i;
- if (clk->ops->disable)
- clk->ops->disable(clk->hw);
+ if (!core->parents) {
+ core->parents = kcalloc(core->num_parents,
+ sizeof(struct clk *), GFP_KERNEL);
+ if (!core->parents)
+ return -ENOMEM;
+ }
- trace_clk_disable_complete(clk);
+ /*
+ * 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_core_lookup.
+ */
+ for (i = 0; i < core->num_parents; i++) {
+ if (core->parents[i] == parent)
+ return i;
- clk_core_disable(clk->parent);
-}
+ if (core->parents[i])
+ continue;
-static void __clk_disable(struct clk *clk)
-{
- if (!clk)
- return;
+ if (!strcmp(core->parent_names[i], parent->name)) {
+ core->parents[i] = clk_core_lookup(parent->name);
+ return i;
+ }
+ }
- clk_core_disable(clk->core);
+ return -EINVAL;
}
-/**
- * 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.
+/*
+ * Update the orphan status of @core and all its children.
*/
-void clk_disable(struct clk *clk)
+static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan)
{
- unsigned long flags;
+ struct clk_core *child;
- if (IS_ERR_OR_NULL(clk))
- return;
+ core->orphan = is_orphan;
- flags = clk_enable_lock();
- __clk_disable(clk);
- clk_enable_unlock(flags);
+ hlist_for_each_entry(child, &core->children, child_node)
+ clk_core_update_orphan_status(child, is_orphan);
}
-EXPORT_SYMBOL_GPL(clk_disable);
-static int clk_core_enable(struct clk_core *clk)
+static void clk_reparent(struct clk_core *core, struct clk_core *new_parent)
{
- int ret = 0;
+ bool was_orphan = core->orphan;
- if (!clk)
- return 0;
+ hlist_del(&core->child_node);
- if (WARN_ON(clk->prepare_count == 0))
- return -ESHUTDOWN;
+ if (new_parent) {
+ bool becomes_orphan = new_parent->orphan;
- if (clk->enable_count == 0) {
- ret = clk_core_enable(clk->parent);
+ /* avoid duplicate POST_RATE_CHANGE notifications */
+ if (new_parent->new_child == core)
+ new_parent->new_child = NULL;
- if (ret)
- return ret;
+ hlist_add_head(&core->child_node, &new_parent->children);
- trace_clk_enable(clk);
+ 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);
+ }
- if (clk->ops->enable)
- ret = clk->ops->enable(clk->hw);
+ core->parent = new_parent;
+}
- trace_clk_enable_complete(clk);
+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;
- if (ret) {
- clk_core_disable(clk->parent);
- return ret;
- }
+ /*
+ * 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 (core->prepare_count) {
+ clk_core_prepare(parent);
+ flags = clk_enable_lock();
+ clk_core_enable(parent);
+ clk_core_enable(core);
+ clk_enable_unlock(flags);
}
- clk->enable_count++;
- return 0;
+ /* update the clk tree topology */
+ flags = clk_enable_lock();
+ clk_reparent(core, parent);
+ clk_enable_unlock(flags);
+
+ return old_parent;
}
-static int __clk_enable(struct clk *clk)
+static void __clk_set_parent_after(struct clk_core *core,
+ struct clk_core *parent,
+ struct clk_core *old_parent)
{
- if (!clk)
- return 0;
+ unsigned long flags;
- return clk_core_enable(clk->core);
+ /*
+ * Finish the migration of prepare state and undo the changes done
+ * for preventing a race with clk_enable().
+ */
+ if (core->prepare_count) {
+ flags = clk_enable_lock();
+ clk_core_disable(core);
+ clk_core_disable(old_parent);
+ clk_enable_unlock(flags);
+ clk_core_unprepare(old_parent);
+ }
}
-/**
- * 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)
+static int __clk_set_parent(struct clk_core *core, struct clk_core *parent,
+ u8 p_index)
{
unsigned long flags;
- int ret;
+ int ret = 0;
+ struct clk_core *old_parent;
- flags = clk_enable_lock();
- ret = __clk_enable(clk);
- clk_enable_unlock(flags);
+ old_parent = __clk_set_parent_before(core, parent);
- return ret;
-}
-EXPORT_SYMBOL_GPL(clk_enable);
+ trace_clk_set_parent(core, parent);
-static unsigned long clk_core_round_rate_nolock(struct clk_core *clk,
- unsigned long rate,
- unsigned long min_rate,
- unsigned long max_rate)
-{
- unsigned long parent_rate = 0;
- struct clk_core *parent;
- struct clk_hw *parent_hw;
+ /* change clock input source */
+ if (parent && core->ops->set_parent)
+ ret = core->ops->set_parent(core->hw, p_index);
- lockdep_assert_held(&prepare_lock);
+ trace_clk_set_parent_complete(core, parent);
- if (!clk)
- return 0;
+ if (ret) {
+ flags = clk_enable_lock();
+ clk_reparent(core, old_parent);
+ clk_enable_unlock(flags);
+ __clk_set_parent_after(core, old_parent, parent);
- parent = clk->parent;
- if (parent)
- parent_rate = parent->rate;
-
- if (clk->ops->determine_rate) {
- parent_hw = parent ? parent->hw : NULL;
- return clk->ops->determine_rate(clk->hw, rate,
- min_rate, max_rate,
- &parent_rate, &parent_hw);
- } 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_core_round_rate_nolock(clk->parent, rate, min_rate,
- max_rate);
- else
- return clk->rate;
-}
+ return ret;
+ }
-/**
- * __clk_determine_rate - get the closest rate actually supported by a clock
- * @hw: determine the rate of this clock
- * @rate: target rate
- * @min_rate: returned rate must be greater than this rate
- * @max_rate: returned rate must be less than this rate
- *
- * Caller must hold prepare_lock. Useful for clk_ops such as .set_rate and
- * .determine_rate.
- */
-unsigned long __clk_determine_rate(struct clk_hw *hw,
- unsigned long rate,
- unsigned long min_rate,
- unsigned long max_rate)
-{
- if (!hw)
- return 0;
+ __clk_set_parent_after(core, parent, old_parent);
- return clk_core_round_rate_nolock(hw->core, rate, min_rate, max_rate);
+ return 0;
}
-EXPORT_SYMBOL_GPL(__clk_determine_rate);
/**
- * __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
+ * __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.
*
- * Caller must hold prepare_lock. Useful for clk_ops such as .set_rate
+ * 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.
*/
-unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
-{
- unsigned long min_rate;
- unsigned long max_rate;
-
- if (!clk)
- return 0;
-
- clk_core_get_boundaries(clk->core, &min_rate, &max_rate);
-
- return clk_core_round_rate_nolock(clk->core, rate, min_rate, max_rate);
-}
-EXPORT_SYMBOL_GPL(__clk_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)
-{
- unsigned long ret;
-
- if (!clk)
- return 0;
-
- clk_prepare_lock();
- ret = __clk_round_rate(clk, rate);
- clk_prepare_unlock();
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(clk_round_rate);
-
-/**
- * __clk_notify - call clk notifier chain
- * @clk: struct clk * that is changing rate
- * @msg: clk notifier type (see include/linux/clk.h)
- * @old_rate: old clk rate
- * @new_rate: new clk rate
- *
- * Triggers a notifier call chain on the clk rate-change notification
- * for 'clk'. Passes a pointer to the struct clk and the previous
- * and current rates to the notifier callback. Intended to be called by
- * internal clock code only. Returns NOTIFY_DONE from the last driver
- * called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if
- * a driver returns that.
- */
-static int __clk_notify(struct clk_core *clk, unsigned long msg,
- unsigned long old_rate, unsigned long new_rate)
-{
- struct clk_notifier *cn;
- struct clk_notifier_data cnd;
- int ret = NOTIFY_DONE;
-
- cnd.old_rate = old_rate;
- cnd.new_rate = new_rate;
-
- list_for_each_entry(cn, &clk_notifier_list, node) {
- if (cn->clk->core == clk) {
- cnd.clk = cn->clk;
- ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
- &cnd);
- }
- }
-
- return ret;
-}
-
-/**
- * __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_core *clk)
-{
- unsigned long parent_accuracy = 0;
- struct clk_core *child;
-
- lockdep_assert_held(&prepare_lock);
-
- 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);
-}
-
-static long clk_core_get_accuracy(struct clk_core *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;
-}
-
-/**
- * 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 *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 its parent.
- *
- * clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
- * if necessary.
- *
- * Caller must hold prepare_lock.
- */
-static void __clk_recalc_rates(struct clk_core *clk, unsigned long msg)
-{
- unsigned long old_rate;
- unsigned long parent_rate = 0;
- struct clk_core *child;
-
- lockdep_assert_held(&prepare_lock);
-
- old_rate = clk->rate;
-
- if (clk->parent)
- parent_rate = clk->parent->rate;
-
- clk->rate = clk_recalc(clk, parent_rate);
-
- /*
- * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
- * & ABORT_RATE_CHANGE notifiers
- */
- if (clk->notifier_count && msg)
- __clk_notify(clk, msg, old_rate, clk->rate);
-
- hlist_for_each_entry(child, &clk->children, child_node)
- __clk_recalc_rates(child, msg);
-}
-
-static unsigned long clk_core_get_rate(struct clk_core *clk)
-{
- unsigned long rate;
-
- clk_prepare_lock();
-
- if (clk && (clk->flags & CLK_GET_RATE_NOCACHE))
- __clk_recalc_rates(clk, 0);
-
- rate = clk_core_get_rate_nolock(clk);
- 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 *clk,
- struct clk_core *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_core_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_core_lookup(parent->name);
- return i;
- }
- }
-
- return -EINVAL;
-}
-
-static void clk_reparent(struct clk_core *clk, struct clk_core *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_core *__clk_set_parent_before(struct clk_core *clk,
- struct clk_core *parent)
-{
- unsigned long flags;
- struct clk_core *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_core_prepare(parent);
- flags = clk_enable_lock();
- clk_core_enable(parent);
- clk_core_enable(clk);
- clk_enable_unlock(flags);
- }
-
- /* 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_core *core,
- struct clk_core *parent,
- struct clk_core *old_parent)
-{
- unsigned long flags;
-
- /*
- * Finish the migration of prepare state and undo the changes done
- * for preventing a race with clk_enable().
- */
- if (core->prepare_count) {
- flags = clk_enable_lock();
- clk_core_disable(core);
- clk_core_disable(old_parent);
- clk_enable_unlock(flags);
- clk_core_unprepare(old_parent);
- }
-}
-
-static int __clk_set_parent(struct clk_core *clk, struct clk_core *parent,
- u8 p_index)
-{
- unsigned long flags;
- int ret = 0;
- struct clk_core *old_parent;
-
- old_parent = __clk_set_parent_before(clk, parent);
-
- trace_clk_set_parent(clk, parent);
-
- /* change clock input source */
- if (parent && clk->ops->set_parent)
- ret = clk->ops->set_parent(clk->hw, p_index);
-
- trace_clk_set_parent_complete(clk, parent);
-
- if (ret) {
- flags = clk_enable_lock();
- clk_reparent(clk, old_parent);
- clk_enable_unlock(flags);
-
- if (clk->prepare_count) {
- flags = clk_enable_lock();
- clk_core_disable(clk);
- clk_core_disable(parent);
- clk_enable_unlock(flags);
- clk_core_unprepare(parent);
- }
- return ret;
- }
-
- __clk_set_parent_after(clk, parent, old_parent);
-
- return 0;
-}
-
-/**
- * __clk_speculate_rates
- * @clk: first clk in the subtree
- * @parent_rate: the "future" rate of clk's parent
- *
- * Walks the subtree of clks starting with clk, speculating rates as it
- * goes and firing off PRE_RATE_CHANGE notifications as necessary.
- *
- * Unlike clk_recalc_rates, clk_speculate_rates exists only for sending
- * pre-rate change notifications and returns early if no clks in the
- * subtree have subscribed to the notifications. Note that if a clk does not
- * implement the .recalc_rate callback then it is assumed that the clock will
- * take on the rate of its parent.
- *
- * Caller must hold prepare_lock.
- */
-static int __clk_speculate_rates(struct clk_core *clk,
- unsigned long parent_rate)
+static int __clk_speculate_rates(struct clk_core *core,
+ unsigned long parent_rate)
{
struct clk_core *child;
unsigned long new_rate;
lockdep_assert_held(&prepare_lock);
- new_rate = clk_recalc(clk, parent_rate);
+ new_rate = clk_recalc(core, parent_rate);
/* 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 (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__, clk->name, ret);
+ __func__, core->name, ret);
goto out;
}
- hlist_for_each_entry(child, &clk->children, child_node) {
+ hlist_for_each_entry(child, &core->children, child_node) {
ret = __clk_speculate_rates(child, new_rate);
if (ret & NOTIFY_STOP_MASK)
break;
return ret;
}
-static void clk_calc_subtree(struct clk_core *clk, unsigned long new_rate,
+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;
- clk->new_rate = new_rate;
- clk->new_parent = new_parent;
- clk->new_parent_index = p_index;
+ 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 */
- clk->new_child = NULL;
- if (new_parent && new_parent != clk->parent)
- new_parent->new_child = clk;
+ core->new_child = NULL;
+ if (new_parent && new_parent != core->parent)
+ new_parent->new_child = core;
- hlist_for_each_entry(child, &clk->children, child_node) {
+ 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 *clk,
+static struct clk_core *clk_calc_new_rates(struct clk_core *core,
unsigned long rate)
{
- struct clk_core *top = clk;
+ struct clk_core *top = core;
struct clk_core *old_parent, *parent;
- struct clk_hw *parent_hw;
unsigned long best_parent_rate = 0;
unsigned long new_rate;
unsigned long min_rate;
long ret;
/* sanity */
- if (IS_ERR_OR_NULL(clk))
+ if (IS_ERR_OR_NULL(core))
return NULL;
/* save parent rate, if it exists */
- parent = old_parent = clk->parent;
+ parent = old_parent = core->parent;
if (parent)
best_parent_rate = parent->rate;
- clk_core_get_boundaries(clk, &min_rate, &max_rate);
+ clk_core_get_boundaries(core, &min_rate, &max_rate);
/* find the closest rate and parent clk/rate */
- if (clk->ops->determine_rate) {
- parent_hw = parent ? parent->hw : NULL;
- ret = clk->ops->determine_rate(clk->hw, rate,
- min_rate,
- max_rate,
- &best_parent_rate,
- &parent_hw);
+ if (core->ops->determine_rate) {
+ struct clk_rate_request req;
+
+ req.rate = rate;
+ req.min_rate = min_rate;
+ req.max_rate = max_rate;
+ 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;
+ }
+
+ ret = core->ops->determine_rate(core->hw, &req);
if (ret < 0)
return NULL;
- new_rate = ret;
- parent = parent_hw ? parent_hw->core : NULL;
- } else if (clk->ops->round_rate) {
- ret = clk->ops->round_rate(clk->hw, rate,
- &best_parent_rate);
+ best_parent_rate = req.best_parent_rate;
+ new_rate = req.rate;
+ parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
+ } else if (core->ops->round_rate) {
+ ret = core->ops->round_rate(core->hw, rate,
+ &best_parent_rate);
if (ret < 0)
return NULL;
new_rate = ret;
if (new_rate < min_rate || new_rate > max_rate)
return NULL;
- } else if (!parent || !(clk->flags & CLK_SET_RATE_PARENT)) {
+ } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) {
/* pass-through clock without adjustable parent */
- clk->new_rate = clk->rate;
+ core->new_rate = core->rate;
return NULL;
} else {
/* pass-through clock with adjustable parent */
/* some clocks must be gated to change parent */
if (parent != old_parent &&
- (clk->flags & CLK_SET_PARENT_GATE) && clk->prepare_count) {
+ (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
pr_debug("%s: %s not gated but wants to reparent\n",
- __func__, clk->name);
+ __func__, core->name);
return NULL;
}
/* try finding the new parent index */
- if (parent && clk->num_parents > 1) {
- p_index = clk_fetch_parent_index(clk, parent);
+ 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, clk->name);
+ __func__, parent->name, core->name);
return NULL;
}
}
- if ((clk->flags & CLK_SET_RATE_PARENT) && parent &&
+ 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(clk, new_rate, parent, p_index);
+ clk_calc_subtree(core, new_rate, parent, p_index);
return top;
}
* 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 *clk,
+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 (clk->rate == clk->new_rate)
+ if (core->rate == core->new_rate)
return NULL;
- if (clk->notifier_count) {
- ret = __clk_notify(clk, event, clk->rate, clk->new_rate);
+ if (core->notifier_count) {
+ ret = __clk_notify(core, event, core->rate, core->new_rate);
if (ret & NOTIFY_STOP_MASK)
- fail_clk = clk;
+ fail_clk = core;
}
- hlist_for_each_entry(child, &clk->children, child_node) {
+ 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 != clk)
+ 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 clk->children yet */
- if (clk->new_child) {
- tmp_clk = clk_propagate_rate_change(clk->new_child, event);
+ /* 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;
}
* walk down a subtree and set the new rates notifying the rate
* change on the way
*/
-static void clk_change_rate(struct clk_core *clk)
+static void clk_change_rate(struct clk_core *core)
{
struct clk_core *child;
struct hlist_node *tmp;
bool skip_set_rate = false;
struct clk_core *old_parent;
- old_rate = clk->rate;
+ old_rate = core->rate;
- if (clk->new_parent)
- best_parent_rate = clk->new_parent->rate;
- else if (clk->parent)
- best_parent_rate = clk->parent->rate;
+ if (core->new_parent)
+ best_parent_rate = core->new_parent->rate;
+ else if (core->parent)
+ best_parent_rate = core->parent->rate;
- if (clk->new_parent && clk->new_parent != clk->parent) {
- old_parent = __clk_set_parent_before(clk, clk->new_parent);
- trace_clk_set_parent(clk, clk->new_parent);
+ 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 (clk->ops->set_rate_and_parent) {
+ if (core->ops->set_rate_and_parent) {
skip_set_rate = true;
- clk->ops->set_rate_and_parent(clk->hw, clk->new_rate,
+ core->ops->set_rate_and_parent(core->hw, core->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);
+ 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(clk, clk->new_parent);
- __clk_set_parent_after(clk, clk->new_parent, old_parent);
+ trace_clk_set_parent_complete(core, core->new_parent);
+ __clk_set_parent_after(core, core->new_parent, old_parent);
}
- trace_clk_set_rate(clk, clk->new_rate);
+ 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);
- if (!skip_set_rate && clk->ops->set_rate)
- clk->ops->set_rate(clk->hw, clk->new_rate, best_parent_rate);
+ trace_clk_set_rate_complete(core, core->new_rate);
- trace_clk_set_rate_complete(clk, clk->new_rate);
+ core->rate = clk_recalc(core, best_parent_rate);
- clk->rate = clk_recalc(clk, best_parent_rate);
+ if (core->notifier_count && old_rate != core->rate)
+ __clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate);
- if (clk->notifier_count && old_rate != clk->rate)
- __clk_notify(clk, POST_RATE_CHANGE, old_rate, clk->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, &clk->children, child_node) {
+ 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 != clk)
+ if (child->new_parent && child->new_parent != core)
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);
+ /* handle the new child who might not be in core->children yet */
+ if (core->new_child)
+ clk_change_rate(core->new_child);
}
-static int clk_core_set_rate_nolock(struct clk_core *clk,
+static int clk_core_set_rate_nolock(struct clk_core *core,
unsigned long req_rate)
{
struct clk_core *top, *fail_clk;
unsigned long rate = req_rate;
int ret = 0;
- if (!clk)
+ if (!core)
return 0;
/* bail early if nothing to do */
- if (rate == clk_core_get_rate_nolock(clk))
+ if (rate == clk_core_get_rate_nolock(core))
return 0;
- if ((clk->flags & CLK_SET_RATE_GATE) && clk->prepare_count)
+ if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
return -EBUSY;
/* calculate new rates and get the topmost changed clock */
- top = clk_calc_new_rates(clk, rate);
+ top = clk_calc_new_rates(core, rate);
if (!top)
return -EINVAL;
/* change the rates */
clk_change_rate(top);
- clk->req_rate = req_rate;
+ core->req_rate = req_rate;
return ret;
}
* @min: desired minimum clock rate in Hz, inclusive
* @max: desired maximum clock rate in Hz, inclusive
*
- * Returns success (0) or negative errno.
+ * Returns success (0) or negative errno.
+ */
+int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
+{
+ int ret = 0;
+
+ 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 (min != clk->min_rate || max != clk->max_rate) {
+ clk->min_rate = min;
+ clk->max_rate = max;
+ ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
+ }
+
+ 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);
+
+/*
+ * .get_parent is mandatory for clocks with multiple possible parents. It is
+ * optional for single-parent clocks. Always call .get_parent if it is
+ * available and WARN if it is missing for multi-parent clocks.
+ *
+ * For single-parent clocks without .get_parent, first check to see if the
+ * .parents array exists, and if so use it to avoid an expensive tree
+ * traversal. If .parents does not exist then walk the tree.
+ */
+static struct clk_core *__clk_init_parent(struct clk_core *core)
+{
+ struct clk_core *ret = NULL;
+ u8 index;
+
+ /* handle the trivial cases */
+
+ if (!core->num_parents)
+ goto out;
+
+ if (core->num_parents == 1) {
+ if (IS_ERR_OR_NULL(core->parent))
+ core->parent = clk_core_lookup(core->parent_names[0]);
+ ret = core->parent;
+ goto out;
+ }
+
+ if (!core->ops->get_parent) {
+ WARN(!core->ops->get_parent,
+ "%s: multi-parent clocks must implement .get_parent\n",
+ __func__);
+ goto out;
+ }
+
+ /*
+ * Do our best to cache parent clocks in core->parents. This prevents
+ * unnecessary and expensive lookups. We don't set core->parent here;
+ * that is done by the calling function.
+ */
+
+ index = core->ops->get_parent(core->hw);
+
+ if (!core->parents)
+ core->parents =
+ kcalloc(core->num_parents, sizeof(struct clk *),
+ GFP_KERNEL);
+
+ ret = clk_core_get_parent_by_index(core, index);
+
+out:
+ return ret;
+}
+
+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;
+ unsigned int i;
+
+ /* 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;
+
+ for (i = 0; i < core->num_parents; i++)
+ if (strcmp(core->parent_names[i], parent_core->name) == 0)
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(clk_has_parent);
+
+static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
+{
+ int ret = 0;
+ int p_index = 0;
+ unsigned long p_rate = 0;
+
+ if (!core)
+ return 0;
+
+ /* prevent racing with updates to the clock topology */
+ clk_prepare_lock();
+
+ if (core->parent == parent)
+ goto out;
+
+ /* verify ops for for multi-parent clks */
+ if ((core->num_parents > 1) && (!core->ops->set_parent)) {
+ ret = -ENOSYS;
+ goto out;
+ }
+
+ /* check that we are allowed to re-parent if the clock is in use */
+ if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* try finding the new parent index */
+ if (parent) {
+ p_index = clk_fetch_parent_index(core, 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, core->name);
+ ret = p_index;
+ goto out;
+ }
+ }
+
+ /* propagate PRE_RATE_CHANGE notifications */
+ ret = __clk_speculate_rates(core, p_rate);
+
+ /* abort if a driver objects */
+ if (ret & NOTIFY_STOP_MASK)
+ goto out;
+
+ /* 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);
+ }
+
+out:
+ clk_prepare_unlock();
+
+ 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)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_set_parent(clk->core, parent ? parent->core : NULL);
+}
+EXPORT_SYMBOL_GPL(clk_set_parent);
+
+/**
+ * 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_rate_range(struct clk *clk, unsigned long min, unsigned long max)
+int clk_set_phase(struct clk *clk, int degrees)
{
- int ret = 0;
+ int ret = -EINVAL;
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;
- }
+ /* sanity check degrees */
+ degrees %= 360;
+ if (degrees < 0)
+ degrees += 360;
clk_prepare_lock();
- if (min != clk->min_rate || max != clk->max_rate) {
- clk->min_rate = min;
- clk->max_rate = max;
- ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
- }
+ trace_clk_set_phase(clk->core, degrees);
+
+ if (clk->core->ops->set_phase)
+ ret = clk->core->ops->set_phase(clk->core->hw, degrees);
+
+ trace_clk_set_phase_complete(clk->core, degrees);
+
+ if (!ret)
+ clk->core->phase = degrees;
clk_prepare_unlock();
return ret;
}
-EXPORT_SYMBOL_GPL(clk_set_rate_range);
+EXPORT_SYMBOL_GPL(clk_set_phase);
-/**
- * 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)
+static int clk_core_get_phase(struct clk_core *core)
{
- if (!clk)
- return 0;
+ int ret;
- return clk_set_rate_range(clk, rate, clk->max_rate);
+ clk_prepare_lock();
+ ret = core->phase;
+ clk_prepare_unlock();
+
+ return ret;
}
-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
+ * clk_get_phase - return the phase shift of a clock signal
+ * @clk: clock signal source
*
- * Returns success (0) or negative errno.
+ * Returns the phase shift of a clock node in degrees, otherwise returns
+ * -EERROR.
*/
-int clk_set_max_rate(struct clk *clk, unsigned long rate)
+int clk_get_phase(struct clk *clk)
{
if (!clk)
return 0;
- return clk_set_rate_range(clk, clk->min_rate, rate);
+ return clk_core_get_phase(clk->core);
}
-EXPORT_SYMBOL_GPL(clk_set_max_rate);
+EXPORT_SYMBOL_GPL(clk_get_phase);
/**
- * clk_get_parent - return the parent of a clk
- * @clk: the clk whose parent gets returned
+ * clk_is_match - check if two clk's point to the same hardware clock
+ * @p: clk compared against q
+ * @q: clk compared against p
*
- * Simply returns clk->parent. Returns NULL if clk is NULL.
+ * 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.
*/
-struct clk *clk_get_parent(struct clk *clk)
+bool clk_is_match(const struct clk *p, const struct clk *q)
{
- struct clk *parent;
+ /* trivial case: identical struct clk's or both NULL */
+ if (p == q)
+ return true;
- clk_prepare_lock();
- parent = __clk_get_parent(clk);
- clk_prepare_unlock();
+ /* true if clk->core pointers match. Avoid derefing garbage */
+ if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
+ if (p->core == q->core)
+ return true;
- return parent;
+ return false;
}
-EXPORT_SYMBOL_GPL(clk_get_parent);
+EXPORT_SYMBOL_GPL(clk_is_match);
-/*
- * .get_parent is mandatory for clocks with multiple possible parents. It is
- * optional for single-parent clocks. Always call .get_parent if it is
- * available and WARN if it is missing for multi-parent clocks.
- *
- * For single-parent clocks without .get_parent, first check to see if the
- * .parents array exists, and if so use it to avoid an expensive tree
- * traversal. If .parents does not exist then walk the tree.
- */
-static struct clk_core *__clk_init_parent(struct clk_core *clk)
-{
- struct clk_core *ret = NULL;
- u8 index;
+/*** debugfs support ***/
- /* handle the trivial cases */
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
- if (!clk->num_parents)
- goto out;
+static struct dentry *rootdir;
+static int inited = 0;
+static DEFINE_MUTEX(clk_debug_lock);
+static HLIST_HEAD(clk_debug_list);
- if (clk->num_parents == 1) {
- if (IS_ERR_OR_NULL(clk->parent))
- clk->parent = clk_core_lookup(clk->parent_names[0]);
- ret = clk->parent;
- goto out;
- }
+static struct hlist_head *all_lists[] = {
+ &clk_root_list,
+ &clk_orphan_list,
+ NULL,
+};
- if (!clk->ops->get_parent) {
- WARN(!clk->ops->get_parent,
- "%s: multi-parent clocks must implement .get_parent\n",
- __func__);
- goto out;
- };
+static struct hlist_head *orphan_list[] = {
+ &clk_orphan_list,
+ NULL,
+};
- /*
- * Do our best to cache parent clocks in clk->parents. This prevents
- * unnecessary and expensive lookups. We don't set clk->parent here;
- * that is done by the calling function.
- */
+static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ if (!c)
+ return;
- index = clk->ops->get_parent(clk->hw);
+ seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n",
+ level * 3 + 1, "",
+ 30 - level * 3, c->name,
+ c->enable_count, c->prepare_count, clk_core_get_rate(c),
+ clk_core_get_accuracy(c), clk_core_get_phase(c));
+}
- if (!clk->parents)
- clk->parents =
- kcalloc(clk->num_parents, sizeof(struct clk *),
- GFP_KERNEL);
+static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
+ int level)
+{
+ struct clk_core *child;
- ret = clk_core_get_parent_by_index(clk, index);
+ if (!c)
+ return;
-out:
- return ret;
-}
+ clk_summary_show_one(s, c, level);
-static void clk_core_reparent(struct clk_core *clk,
- struct clk_core *new_parent)
-{
- clk_reparent(clk, new_parent);
- __clk_recalc_accuracies(clk);
- __clk_recalc_rates(clk, POST_RATE_CHANGE);
+ hlist_for_each_entry(child, &c->children, child_node)
+ clk_summary_show_subtree(s, child, level + 1);
}
-/**
- * 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)
+static int clk_summary_show(struct seq_file *s, void *data)
{
- struct clk_core *core, *parent_core;
- unsigned int i;
+ struct clk_core *c;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
- /* NULL clocks should be nops, so return success if either is NULL. */
- if (!clk || !parent)
- return true;
+ seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n");
+ seq_puts(s, "----------------------------------------------------------------------------------------\n");
- core = clk->core;
- parent_core = parent->core;
+ clk_prepare_lock();
- /* Optimize for the case where the parent is already the parent. */
- if (core->parent == parent_core)
- return true;
+ for (; *lists; lists++)
+ hlist_for_each_entry(c, *lists, child_node)
+ clk_summary_show_subtree(s, c, 0);
- for (i = 0; i < core->num_parents; i++)
- if (strcmp(core->parent_names[i], parent_core->name) == 0)
- return true;
+ clk_prepare_unlock();
- return false;
+ return 0;
}
-EXPORT_SYMBOL_GPL(clk_has_parent);
-static int clk_core_set_parent(struct clk_core *clk, struct clk_core *parent)
+
+static int clk_summary_open(struct inode *inode, struct file *file)
{
- int ret = 0;
- int p_index = 0;
- unsigned long p_rate = 0;
+ return single_open(file, clk_summary_show, inode->i_private);
+}
- if (!clk)
- return 0;
+static const struct file_operations clk_summary_fops = {
+ .open = clk_summary_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
- /* prevent racing with updates to the clock topology */
- clk_prepare_lock();
+static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
+{
+ if (!c)
+ return;
- if (clk->parent == parent)
- goto out;
+ /* 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, "\"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));
+}
- /* verify ops for for multi-parent clks */
- if ((clk->num_parents > 1) && (!clk->ops->set_parent)) {
- ret = -ENOSYS;
- goto out;
- }
+static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
+{
+ struct clk_core *child;
- /* 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;
- }
+ if (!c)
+ return;
- /* 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;
- }
+ 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);
}
- /* propagate PRE_RATE_CHANGE notifications */
- ret = __clk_speculate_rates(clk, p_rate);
+ seq_printf(s, "}");
+}
+
+static int clk_dump(struct seq_file *s, void *data)
+{
+ struct clk_core *c;
+ bool first_node = true;
+ struct hlist_head **lists = (struct hlist_head **)s->private;
- /* abort if a driver objects */
- if (ret & NOTIFY_STOP_MASK)
- goto out;
+ seq_printf(s, "{");
- /* do the re-parent */
- ret = __clk_set_parent(clk, parent, p_index);
+ clk_prepare_lock();
- /* propagate rate an accuracy recalculation accordingly */
- if (ret) {
- __clk_recalc_rates(clk, ABORT_RATE_CHANGE);
- } else {
- __clk_recalc_rates(clk, POST_RATE_CHANGE);
- __clk_recalc_accuracies(clk);
+ for (; *lists; lists++) {
+ hlist_for_each_entry(c, *lists, child_node) {
+ if (!first_node)
+ seq_puts(s, ",");
+ first_node = false;
+ clk_dump_subtree(s, c, 0);
+ }
}
-out:
clk_prepare_unlock();
- return ret;
+ seq_puts(s, "}\n");
+ return 0;
}
-/**
- * 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)
-{
- if (!clk)
- return 0;
- return clk_core_set_parent(clk->core, parent ? parent->core : NULL);
+static int clk_dump_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_dump, inode->i_private);
}
-EXPORT_SYMBOL_GPL(clk_set_parent);
-/**
- * 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)
+static const struct file_operations clk_dump_fops = {
+ .open = clk_dump_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
{
- int ret = -EINVAL;
+ struct dentry *d;
+ int ret = -ENOMEM;
- if (!clk)
- return 0;
+ if (!core || !pdentry) {
+ ret = -EINVAL;
+ goto out;
+ }
- /* sanity check degrees */
- degrees %= 360;
- if (degrees < 0)
- degrees += 360;
+ d = debugfs_create_dir(core->name, pdentry);
+ if (!d)
+ goto out;
- clk_prepare_lock();
+ core->dentry = d;
- trace_clk_set_phase(clk->core, degrees);
+ d = debugfs_create_u32("clk_rate", S_IRUGO, core->dentry,
+ (u32 *)&core->rate);
+ if (!d)
+ goto err_out;
- if (clk->core->ops->set_phase)
- ret = clk->core->ops->set_phase(clk->core->hw, degrees);
+ d = debugfs_create_u32("clk_accuracy", S_IRUGO, core->dentry,
+ (u32 *)&core->accuracy);
+ if (!d)
+ goto err_out;
- trace_clk_set_phase_complete(clk->core, degrees);
+ d = debugfs_create_u32("clk_phase", S_IRUGO, core->dentry,
+ (u32 *)&core->phase);
+ if (!d)
+ goto err_out;
- if (!ret)
- clk->core->phase = degrees;
+ d = debugfs_create_x32("clk_flags", S_IRUGO, core->dentry,
+ (u32 *)&core->flags);
+ if (!d)
+ goto err_out;
- clk_prepare_unlock();
+ d = debugfs_create_u32("clk_prepare_count", S_IRUGO, core->dentry,
+ (u32 *)&core->prepare_count);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("clk_enable_count", S_IRUGO, core->dentry,
+ (u32 *)&core->enable_count);
+ if (!d)
+ goto err_out;
+ d = debugfs_create_u32("clk_notifier_count", S_IRUGO, core->dentry,
+ (u32 *)&core->notifier_count);
+ if (!d)
+ goto err_out;
+
+ if (core->ops->debug_init) {
+ ret = core->ops->debug_init(core->hw, core->dentry);
+ if (ret)
+ goto err_out;
+ }
+
+ ret = 0;
+ goto out;
+
+err_out:
+ debugfs_remove_recursive(core->dentry);
+ core->dentry = NULL;
+out:
return ret;
}
-EXPORT_SYMBOL_GPL(clk_set_phase);
-static int clk_core_get_phase(struct clk_core *clk)
+/**
+ * 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 int clk_debug_register(struct clk_core *core)
{
int ret = 0;
- if (!clk)
- goto out;
+ mutex_lock(&clk_debug_lock);
+ hlist_add_head(&core->debug_node, &clk_debug_list);
- clk_prepare_lock();
- ret = clk->phase;
- clk_prepare_unlock();
+ if (!inited)
+ goto unlock;
+
+ ret = clk_debug_create_one(core, rootdir);
+unlock:
+ mutex_unlock(&clk_debug_lock);
-out:
return ret;
}
-EXPORT_SYMBOL_GPL(clk_get_phase);
-/**
- * clk_get_phase - return the phase shift of a clock signal
- * @clk: clock signal source
+ /**
+ * clk_debug_unregister - remove a clk node from the debugfs clk directory
+ * @core: the clk being removed from the debugfs clk directory
*
- * Returns the phase shift of a clock node in degrees, otherwise returns
- * -EERROR.
+ * 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_init.
*/
-int clk_get_phase(struct clk *clk)
+static void clk_debug_unregister(struct clk_core *core)
{
- if (!clk)
- return 0;
+ mutex_lock(&clk_debug_lock);
+ hlist_del_init(&core->debug_node);
+ debugfs_remove_recursive(core->dentry);
+ core->dentry = NULL;
+ mutex_unlock(&clk_debug_lock);
+}
- return clk_core_get_phase(clk->core);
+struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode,
+ void *data, const struct file_operations *fops)
+{
+ struct dentry *d = NULL;
+
+ if (hw->core->dentry)
+ d = debugfs_create_file(name, mode, hw->core->dentry, data,
+ fops);
+
+ return d;
}
+EXPORT_SYMBOL_GPL(clk_debugfs_add_file);
/**
- * 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.
+ * clk_debug_init - lazily populate the debugfs clk directory
*
- * Returns false otherwise. Note that two NULL clks are treated as matching.
+ * 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.
*/
-bool clk_is_match(const struct clk *p, const struct clk *q)
+static int __init clk_debug_init(void)
{
- /* trivial case: identical struct clk's or both NULL */
- if (p == q)
- return true;
+ struct clk_core *core;
+ struct dentry *d;
- /* true if clk->core pointers match. Avoid derefing garbage */
- if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
- if (p->core == q->core)
- return true;
+ rootdir = debugfs_create_dir("clk", NULL);
- return false;
+ if (!rootdir)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
+ &clk_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
+ &clk_dump_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
+ &orphan_list, &clk_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
+ &orphan_list, &clk_dump_fops);
+ if (!d)
+ return -ENOMEM;
+
+ 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;
}
-EXPORT_SYMBOL_GPL(clk_is_match);
+late_initcall(clk_debug_init);
+#else
+static inline int clk_debug_register(struct clk_core *core) { return 0; }
+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_init - initialize the data structures in a struct clk
int i, ret = 0;
struct clk_core *orphan;
struct hlist_node *tmp2;
- struct clk_core *clk;
+ struct clk_core *core;
unsigned long rate;
if (!clk_user)
return -EINVAL;
- clk = clk_user->core;
+ core = clk_user->core;
clk_prepare_lock();
/* check to see if a clock with this name is already registered */
- if (clk_core_lookup(clk->name)) {
+ if (clk_core_lookup(core->name)) {
pr_debug("%s: clk %s already initialized\n",
- __func__, clk->name);
+ __func__, core->name);
ret = -EEXIST;
goto out;
}
/* check that clk_ops are sane. See Documentation/clk.txt */
- if (clk->ops->set_rate &&
- !((clk->ops->round_rate || clk->ops->determine_rate) &&
- clk->ops->recalc_rate)) {
+ if (core->ops->set_rate &&
+ !((core->ops->round_rate || core->ops->determine_rate) &&
+ core->ops->recalc_rate)) {
pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
- __func__, clk->name);
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
- if (clk->ops->set_parent && !clk->ops->get_parent) {
+ if (core->ops->set_parent && !core->ops->get_parent) {
pr_warning("%s: %s must implement .get_parent & .set_parent\n",
- __func__, clk->name);
+ __func__, core->name);
ret = -EINVAL;
goto out;
}
- if (clk->ops->set_rate_and_parent &&
- !(clk->ops->set_parent && clk->ops->set_rate)) {
+ if (core->ops->set_rate_and_parent &&
+ !(core->ops->set_parent && core->ops->set_rate)) {
pr_warn("%s: %s must implement .set_parent & .set_rate\n",
- __func__, clk->name);
+ __func__, core->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],
+ for (i = 0; i < core->num_parents; i++)
+ WARN(!core->parent_names[i],
"%s: invalid NULL in %s's .parent_names\n",
- __func__, clk->name);
+ __func__, core->name);
/*
* Allocate an array of struct clk *'s to avoid unnecessary string
* look-ups of clk's possible parents. This can fail for clocks passed
- * in to clk_init during early boot; thus any access to clk->parents[]
+ * in to clk_init during early boot; thus any access to core->parents[]
* must always check for a NULL pointer and try to populate it if
* necessary.
*
- * If clk->parents is not NULL we skip this entire block. This allows
- * for clock drivers to statically initialize clk->parents.
+ * If core->parents is not NULL we skip this entire block. This allows
+ * for clock drivers to statically initialize core->parents.
*/
- if (clk->num_parents > 1 && !clk->parents) {
- clk->parents = kcalloc(clk->num_parents, sizeof(struct clk *),
+ if (core->num_parents > 1 && !core->parents) {
+ core->parents = kcalloc(core->num_parents, sizeof(struct clk *),
GFP_KERNEL);
/*
* clk_core_lookup returns NULL for parents that have not been
* for a NULL pointer. We can always perform lazy lookups for
* missing parents later on.
*/
- if (clk->parents)
- for (i = 0; i < clk->num_parents; i++)
- clk->parents[i] =
- clk_core_lookup(clk->parent_names[i]);
+ if (core->parents)
+ for (i = 0; i < core->num_parents; i++)
+ core->parents[i] =
+ clk_core_lookup(core->parent_names[i]);
}
- clk->parent = __clk_init_parent(clk);
+ core->parent = __clk_init_parent(core);
/*
- * Populate clk->parent if parent has already been __clk_init'd. If
+ * Populate core->parent if parent has already been __clk_init'd. If
* parent has not yet been __clk_init'd then place clk in the orphan
* list. If clk has set the CLK_IS_ROOT flag then place it in the root
* clk list.
* clocks and re-parent any that are children of the clock currently
* being clk_init'd.
*/
- if (clk->parent)
- hlist_add_head(&clk->child_node,
- &clk->parent->children);
- else if (clk->flags & CLK_IS_ROOT)
- hlist_add_head(&clk->child_node, &clk_root_list);
- else
- hlist_add_head(&clk->child_node, &clk_orphan_list);
+ if (core->parent) {
+ hlist_add_head(&core->child_node,
+ &core->parent->children);
+ core->orphan = core->parent->orphan;
+ } else if (core->flags & CLK_IS_ROOT) {
+ 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;
+ }
/*
* Set clk's accuracy. The preferred method is to use
* 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;
+ 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
- clk->accuracy = 0;
+ 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 (clk->ops->get_phase)
- clk->phase = clk->ops->get_phase(clk->hw);
+ if (core->ops->get_phase)
+ core->phase = core->ops->get_phase(core->hw);
else
- clk->phase = 0;
+ core->phase = 0;
/*
* Set clk's rate. The preferred method is to use .recalc_rate. For
* parent's rate. If a clock doesn't have a parent (or is orphaned)
* then rate is set to zero.
*/
- if (clk->ops->recalc_rate)
- rate = clk->ops->recalc_rate(clk->hw,
- clk_core_get_rate_nolock(clk->parent));
- else if (clk->parent)
- rate = clk->parent->rate;
+ 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;
- clk->rate = clk->req_rate = rate;
+ core->rate = core->req_rate = rate;
/*
* walk the list of orphan clocks and reparent any that are children of
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_core_reparent(orphan, clk);
+ if (i >= 0 && i < orphan->num_parents &&
+ !strcmp(core->name, orphan->parent_names[i]))
+ clk_core_reparent(orphan, core);
continue;
}
for (i = 0; i < orphan->num_parents; i++)
- if (!strcmp(clk->name, orphan->parent_names[i])) {
- clk_core_reparent(orphan, clk);
+ if (!strcmp(core->name, orphan->parent_names[i])) {
+ clk_core_reparent(orphan, core);
break;
}
}
* Please consider other ways of solving initialization problems before
* using this callback, as its use is discouraged.
*/
- if (clk->ops->init)
- clk->ops->init(clk->hw);
+ if (core->ops->init)
+ core->ops->init(core->hw);
- kref_init(&clk->ref);
+ kref_init(&core->ref);
out:
clk_prepare_unlock();
if (!ret)
- clk_debug_register(clk);
+ clk_debug_register(core);
return ret;
}
*
* 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
+ * 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 *clk;
+ struct clk_core *core;
- clk = kzalloc(sizeof(*clk), GFP_KERNEL);
- if (!clk) {
- pr_err("%s: could not allocate clk\n", __func__);
+ core = kzalloc(sizeof(*core), GFP_KERNEL);
+ if (!core) {
ret = -ENOMEM;
goto fail_out;
}
- clk->name = kstrdup_const(hw->init->name, GFP_KERNEL);
- if (!clk->name) {
- pr_err("%s: could not allocate clk->name\n", __func__);
+ core->name = kstrdup_const(hw->init->name, GFP_KERNEL);
+ if (!core->name) {
ret = -ENOMEM;
goto fail_name;
}
- clk->ops = hw->init->ops;
+ core->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->core = clk;
+ 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 */
- clk->parent_names = kcalloc(clk->num_parents, sizeof(char *),
+ core->parent_names = kcalloc(core->num_parents, sizeof(char *),
GFP_KERNEL);
- if (!clk->parent_names) {
- pr_err("%s: could not allocate clk->parent_names\n", __func__);
+ if (!core->parent_names) {
ret = -ENOMEM;
goto fail_parent_names;
}
/* copy each string name in case parent_names is __initdata */
- for (i = 0; i < clk->num_parents; i++) {
- clk->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
+ for (i = 0; i < core->num_parents; i++) {
+ core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
GFP_KERNEL);
- if (!clk->parent_names[i]) {
- pr_err("%s: could not copy parent_names\n", __func__);
+ if (!core->parent_names[i]) {
ret = -ENOMEM;
goto fail_parent_names_copy;
}
}
- INIT_HLIST_HEAD(&clk->clks);
+ INIT_HLIST_HEAD(&core->clks);
hw->clk = __clk_create_clk(hw, NULL, NULL);
if (IS_ERR(hw->clk)) {
- pr_err("%s: could not allocate per-user clk\n", __func__);
ret = PTR_ERR(hw->clk);
goto fail_parent_names_copy;
}
fail_parent_names_copy:
while (--i >= 0)
- kfree_const(clk->parent_names[i]);
- kfree(clk->parent_names);
+ kfree_const(core->parent_names[i]);
+ kfree(core->parent_names);
fail_parent_names:
- kfree_const(clk->name);
+ kfree_const(core->name);
fail_name:
- kfree(clk);
+ kfree(core);
fail_out:
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(clk_register);
-/*
- * Free memory allocated for a clock.
- * Caller must hold prepare_lock.
- */
+/* Free memory allocated for a clock. */
static void __clk_release(struct kref *ref)
{
- struct clk_core *clk = container_of(ref, struct clk_core, ref);
- int i = clk->num_parents;
+ struct clk_core *core = container_of(ref, struct clk_core, ref);
+ int i = core->num_parents;
lockdep_assert_held(&prepare_lock);
- kfree(clk->parents);
+ kfree(core->parents);
while (--i >= 0)
- kfree_const(clk->parent_names[i]);
+ kfree_const(core->parent_names[i]);
- kfree(clk->parent_names);
- kfree_const(clk->name);
- kfree(clk);
+ kfree(core->parent_names);
+ kfree_const(core->name);
+ kfree(core);
}
/*
unsigned int idx = clkspec->args[0];
if (idx >= clk_data->clk_num) {
- pr_err("%s: invalid clock index %d\n", __func__, idx);
+ pr_err("%s: invalid clock index %u\n", __func__, idx);
return ERR_PTR(-EINVAL);
}
u32 pv;
int rc;
int count;
+ struct clk *clk;
if (index < 0)
return NULL;
if (of_property_read_string_index(clkspec.np, "clock-output-names",
index,
- &clk_name) < 0)
- clk_name = clkspec.np->name;
+ &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 {
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
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 =
- kzalloc(sizeof(struct clock_provider), GFP_KERNEL);
+ struct clock_provider *parent;
+
+ 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 = np;
+ parent->np = of_node_get(np);
list_add_tail(&parent->node, &clk_provider_list);
}
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;
}
Code Review / kvmfornfv.git / blobdiff