clk: Don't return negative numbers for unsigned values with !clk

Some of the helper functions return negative error codes if
passed a NULL clock. This can lead to confusing behavior when the
expected return value is unsigned. Fix up these accessors so that
they return unsigned values (or bool in the case of is_enabled).
This way we can't interpret NULL clocks as having valid and
interesting values.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

drivers/clk/clk.c

@@ -261,7 +261,7 @@ inline struct clk_hw *__clk_get_hw(struct clk *clk)
 
 inline u8 __clk_get_num_parents(struct clk *clk)
 {
-	return !clk ? -EINVAL : clk->num_parents;
+	return !clk ? 0 : clk->num_parents;
 }
 
 inline struct clk *__clk_get_parent(struct clk *clk)
@@ -269,14 +269,14 @@ inline struct clk *__clk_get_parent(struct clk *clk)
 	return !clk ? NULL : clk->parent;
 }
 
-inline int __clk_get_enable_count(struct clk *clk)
+inline unsigned int __clk_get_enable_count(struct clk *clk)
 {
-	return !clk ? -EINVAL : clk->enable_count;
+	return !clk ? 0 : clk->enable_count;
 }
 
-inline int __clk_get_prepare_count(struct clk *clk)
+inline unsigned int __clk_get_prepare_count(struct clk *clk)
 {
-	return !clk ? -EINVAL : clk->prepare_count;
+	return !clk ? 0 : clk->prepare_count;
 }
 
 unsigned long __clk_get_rate(struct clk *clk)
@@ -302,15 +302,15 @@ out:
 
 inline unsigned long __clk_get_flags(struct clk *clk)
 {
-	return !clk ? -EINVAL : clk->flags;
+	return !clk ? 0 : clk->flags;
 }
 
-int __clk_is_enabled(struct clk *clk)
+bool __clk_is_enabled(struct clk *clk)
 {
 	int ret;
 
 	if (!clk)
-		return -EINVAL;
+		return false;
 
 	/*
 	 * .is_enabled is only mandatory for clocks that gate
@@ -323,7 +323,7 @@ int __clk_is_enabled(struct clk *clk)
 
 	ret = clk->ops->is_enabled(clk->hw);
 out:
-	return ret;
+	return !!ret;
 }
 
 static struct clk *__clk_lookup_subtree(const char *name, struct clk *clk)
@@ -568,7 +568,7 @@ unsigned long __clk_round_rate(struct clk *clk, unsigned long rate)
 	unsigned long parent_rate = 0;
 
 	if (!clk)
-		return -EINVAL;
+		return 0;
 
 	if (!clk->ops->round_rate) {
 		if (clk->flags & CLK_SET_RATE_PARENT)

include/linux/clk-provider.h

@@ -339,11 +339,11 @@ const char *__clk_get_name(struct clk *clk);
 struct clk_hw *__clk_get_hw(struct clk *clk);
 u8 __clk_get_num_parents(struct clk *clk);
 struct clk *__clk_get_parent(struct clk *clk);
-inline int __clk_get_enable_count(struct clk *clk);
-inline int __clk_get_prepare_count(struct clk *clk);
+inline unsigned int __clk_get_enable_count(struct clk *clk);
+inline unsigned int __clk_get_prepare_count(struct clk *clk);
 unsigned long __clk_get_rate(struct clk *clk);
 unsigned long __clk_get_flags(struct clk *clk);
-int __clk_is_enabled(struct clk *clk);
+bool __clk_is_enabled(struct clk *clk);
 struct clk *__clk_lookup(const char *name);
 
 /*