1 files changed, 142 insertions, 40 deletions

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b68e200829f2..f0f2b599fd7e 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -429,7 +429,7 @@ static void clk_core_fill_parent_index(struct clk_core *core, u8 index)
 			parent = ERR_PTR(-EPROBE_DEFER);
 	} else {
 		parent = clk_core_get(core, index);
-		if (IS_ERR(parent) && PTR_ERR(parent) == -ENOENT && entry->name)
+		if (PTR_ERR(parent) == -ENOENT && entry->name)
 			parent = clk_core_lookup(entry->name);
 	}
 
@@ -2996,6 +2996,41 @@ static int clk_dump_show(struct seq_file *s, void *data)
 }
 DEFINE_SHOW_ATTRIBUTE(clk_dump);
 
+#undef CLOCK_ALLOW_WRITE_DEBUGFS
+#ifdef CLOCK_ALLOW_WRITE_DEBUGFS
+/*
+ * This can be dangerous, therefore don't provide any real compile time
+ * configuration option for this feature.
+ * People who want to use this will need to modify the source code directly.
+ */
+static int clk_rate_set(void *data, u64 val)
+{
+	struct clk_core *core = data;
+	int ret;
+
+	clk_prepare_lock();
+	ret = clk_core_set_rate_nolock(core, val);
+	clk_prepare_unlock();
+
+	return ret;
+}
+
+#define clk_rate_mode	0644
+#else
+#define clk_rate_set	NULL
+#define clk_rate_mode	0444
+#endif
+
+static int clk_rate_get(void *data, u64 *val)
+{
+	struct clk_core *core = data;
+
+	*val = core->rate;
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(clk_rate_fops, clk_rate_get, clk_rate_set, "%llu\n");
+
 static const struct {
 	unsigned long flag;
 	const char *name;
@@ -3145,7 +3180,8 @@ static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
 	root = debugfs_create_dir(core->name, pdentry);
 	core->dentry = root;
 
-	debugfs_create_ulong("clk_rate", 0444, root, &core->rate);
+	debugfs_create_file("clk_rate", clk_rate_mode, root, core,
+			    &clk_rate_fops);
 	debugfs_create_file("clk_min_rate", 0444, root, core, &clk_min_rate_fops);
 	debugfs_create_file("clk_max_rate", 0444, root, core, &clk_max_rate_fops);
 	debugfs_create_ulong("clk_accuracy", 0444, root, &core->accuracy);
@@ -3249,6 +3285,34 @@ static inline void clk_debug_unregister(struct clk_core *core)
 }
 #endif
 
+static void clk_core_reparent_orphans_nolock(void)
+{
+	struct clk_core *orphan;
+	struct hlist_node *tmp2;
+
+	/*
+	 * walk the list of orphan clocks and reparent any that newly finds a
+	 * parent.
+	 */
+	hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
+		struct clk_core *parent = __clk_init_parent(orphan);
+
+		/*
+		 * We need to use __clk_set_parent_before() and _after() to
+		 * to properly migrate any prepare/enable count of the orphan
+		 * clock. This is important for CLK_IS_CRITICAL clocks, which
+		 * are enabled during init but might not have a parent yet.
+		 */
+		if (parent) {
+			/* update the clk tree topology */
+			__clk_set_parent_before(orphan, parent);
+			__clk_set_parent_after(orphan, parent, NULL);
+			__clk_recalc_accuracies(orphan);
+			__clk_recalc_rates(orphan, 0);
+		}
+	}
+}
+
 /**
  * __clk_core_init - initialize the data structures in a struct clk_core
  * @core:	clk_core being initialized
@@ -3259,8 +3323,6 @@ static inline void clk_debug_unregister(struct clk_core *core)
 static int __clk_core_init(struct clk_core *core)
 {
 	int ret;
-	struct clk_core *orphan;
-	struct hlist_node *tmp2;
 	unsigned long rate;
 
 	if (!core)
@@ -3312,6 +3374,26 @@ static int __clk_core_init(struct clk_core *core)
 		goto out;
 	}
 
+	/*
+	 * optional platform-specific magic
+	 *
+	 * The .init callback is not used by any of the basic clock types, but
+	 * exists for weird hardware that must perform initialization magic for
+	 * CCF to get an accurate view of clock for any other callbacks. It may
+	 * also be used needs to perform dynamic allocations. Such allocation
+	 * must be freed in the terminate() callback.
+	 * This callback shall not be used to initialize the parameters state,
+	 * such as rate, parent, etc ...
+	 *
+	 * If it exist, this callback should called before any other callback of
+	 * the clock
+	 */
+	if (core->ops->init) {
+		ret = core->ops->init(core->hw);
+		if (ret)
+			goto out;
+	}
+
 	core->parent = __clk_init_parent(core);
 
 	/*
@@ -3337,17 +3419,6 @@ static int __clk_core_init(struct clk_core *core)
 	}
 
 	/*
-	 * optional platform-specific magic
-	 *
-	 * The .init callback is not used by any of the basic clock types, but
-	 * exists for weird hardware that must perform initialization magic.
-	 * Please consider other ways of solving initialization problems before
-	 * using this callback, as its use is discouraged.
-	 */
-	if (core->ops->init)
-		core->ops->init(core->hw);
-
-	/*
 	 * Set clk's accuracy.  The preferred method is to use
 	 * .recalc_accuracy. For simple clocks and lazy developers the default
 	 * fallback is to use the parent's accuracy.  If a clock doesn't have a
@@ -3400,34 +3471,26 @@ static int __clk_core_init(struct clk_core *core)
 	if (core->flags & CLK_IS_CRITICAL) {
 		unsigned long flags;
 
-		clk_core_prepare(core);
+		ret = clk_core_prepare(core);
+		if (ret) {
+			pr_warn("%s: critical clk '%s' failed to prepare\n",
+			       __func__, core->name);
+			goto out;
+		}
 
 		flags = clk_enable_lock();
-		clk_core_enable(core);
+		ret = clk_core_enable(core);
 		clk_enable_unlock(flags);
+		if (ret) {
+			pr_warn("%s: critical clk '%s' failed to enable\n",
+			       __func__, core->name);
+			clk_core_unprepare(core);
+			goto out;
+		}
 	}
 
-	/*
-	 * walk the list of orphan clocks and reparent any that newly finds a
-	 * parent.
-	 */
-	hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
-		struct clk_core *parent = __clk_init_parent(orphan);
+	clk_core_reparent_orphans_nolock();
 
-		/*
-		 * We need to use __clk_set_parent_before() and _after() to
-		 * to properly migrate any prepare/enable count of the orphan
-		 * clock. This is important for CLK_IS_CRITICAL clocks, which
-		 * are enabled during init but might not have a parent yet.
-		 */
-		if (parent) {
-			/* update the clk tree topology */
-			__clk_set_parent_before(orphan, parent);
-			__clk_set_parent_after(orphan, parent, NULL);
-			__clk_recalc_accuracies(orphan);
-			__clk_recalc_rates(orphan, 0);
-		}
-	}
 
 	kref_init(&core->ref);
 out:
@@ -3720,6 +3783,28 @@ fail_out:
 }
 
 /**
+ * dev_or_parent_of_node() - Get device node of @dev or @dev's parent
+ * @dev: Device to get device node of
+ *
+ * Return: device node pointer of @dev, or the device node pointer of
+ * @dev->parent if dev doesn't have a device node, or NULL if neither
+ * @dev or @dev->parent have a device node.
+ */
+static struct device_node *dev_or_parent_of_node(struct device *dev)
+{
+	struct device_node *np;
+
+	if (!dev)
+		return NULL;
+
+	np = dev_of_node(dev);
+	if (!np)
+		np = dev_of_node(dev->parent);
+
+	return np;
+}
+
+/**
  * clk_register - allocate a new clock, register it and return an opaque cookie
  * @dev: device that is registering this clock
  * @hw: link to hardware-specific clock data
@@ -3734,7 +3819,7 @@ fail_out:
  */
 struct clk *clk_register(struct device *dev, struct clk_hw *hw)
 {
-	return __clk_register(dev, dev_of_node(dev), hw);
+	return __clk_register(dev, dev_or_parent_of_node(dev), hw);
 }
 EXPORT_SYMBOL_GPL(clk_register);
 
@@ -3750,7 +3835,8 @@ EXPORT_SYMBOL_GPL(clk_register);
  */
 int clk_hw_register(struct device *dev, struct clk_hw *hw)
 {
-	return PTR_ERR_OR_ZERO(__clk_register(dev, dev_of_node(dev), hw));
+	return PTR_ERR_OR_ZERO(__clk_register(dev, dev_or_parent_of_node(dev),
+			       hw));
 }
 EXPORT_SYMBOL_GPL(clk_hw_register);
 
@@ -3853,6 +3939,7 @@ static void clk_core_evict_parent_cache(struct clk_core *core)
 void clk_unregister(struct clk *clk)
 {
 	unsigned long flags;
+	const struct clk_ops *ops;
 
 	if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
 		return;
@@ -3861,7 +3948,8 @@ void clk_unregister(struct clk *clk)
 
 	clk_prepare_lock();
 
-	if (clk->core->ops == &clk_nodrv_ops) {
+	ops = clk->core->ops;
+	if (ops == &clk_nodrv_ops) {
 		pr_err("%s: unregistered clock: %s\n", __func__,
 		       clk->core->name);
 		goto unlock;
@@ -3874,6 +3962,9 @@ void clk_unregister(struct clk *clk)
 	clk->core->ops = &clk_nodrv_ops;
 	clk_enable_unlock(flags);
 
+	if (ops->terminate)
+		ops->terminate(clk->core->hw);
+
 	if (!hlist_empty(&clk->core->children)) {
 		struct clk_core *child;
 		struct hlist_node *t;
@@ -4179,6 +4270,13 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
 EXPORT_SYMBOL_GPL(clk_notifier_unregister);
 
 #ifdef CONFIG_OF
+static void clk_core_reparent_orphans(void)
+{
+	clk_prepare_lock();
+	clk_core_reparent_orphans_nolock();
+	clk_prepare_unlock();
+}
+
 /**
  * struct of_clk_provider - Clock provider registration structure
  * @link: Entry in global list of clock providers
@@ -4274,6 +4372,8 @@ int of_clk_add_provider(struct device_node *np,
 	mutex_unlock(&of_clk_mutex);
 	pr_debug("Added clock from %pOF\n", np);
 
+	clk_core_reparent_orphans();
+
 	ret = of_clk_set_defaults(np, true);
 	if (ret < 0)
 		of_clk_del_provider(np);
@@ -4309,6 +4409,8 @@ int of_clk_add_hw_provider(struct device_node *np,
 	mutex_unlock(&of_clk_mutex);
 	pr_debug("Added clk_hw provider from %pOF\n", np);
 
+	clk_core_reparent_orphans();
+
 	ret = of_clk_set_defaults(np, true);
 	if (ret < 0)
 		of_clk_del_provider(np);