[PATCH 1/3] drivers: clk: Add clk_get_children support

From: Jolly Shah
Date: Wed Feb 28 2018 - 17:28:42 EST


From: Jolly Shah <jolly.shah@xxxxxxxxxx>

This API helps to determine the users for any clock.

Signed-off-by: Jolly Shah <jollys@xxxxxxxxxx>
Signed-off-by: Tejas Patel <tejasp@xxxxxxxxxx>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx>
---
drivers/clk/clk.c | 28 ++++++++++++++++++++++++++++
include/linux/clk-provider.h | 1 +
2 files changed, 29 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0f686a9..947a18b 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -274,6 +274,34 @@ struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
}
EXPORT_SYMBOL_GPL(clk_hw_get_parent);

+static unsigned int sibling;
+
+static void clk_show_subtree(struct clk_core *c,
+ int level)
+{
+ struct clk_core *child;
+
+ if (!c)
+ return;
+
+ if (level == 1)
+ sibling++;
+
+ hlist_for_each_entry(child, &c->children, child_node)
+ clk_show_subtree(child, level + 1);
+}
+
+unsigned int clk_get_children(char *name)
+{
+ struct clk_core *core;
+ struct clk *pclk = __clk_lookup(name);
+
+ sibling = 0;
+ core = pclk->core;
+ clk_show_subtree(core, 0);
+ return sibling;
+}
+
static struct clk_core *__clk_lookup_subtree(const char *name,
struct clk_core *core)
{
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index f711be6..e94dfb2 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -745,6 +745,7 @@ unsigned int __clk_get_enable_count(struct clk *clk);
unsigned long clk_hw_get_rate(const struct clk_hw *hw);
unsigned long __clk_get_flags(struct clk *clk);
unsigned long clk_hw_get_flags(const struct clk_hw *hw);
+unsigned int clk_get_children(char *name);
bool clk_hw_is_prepared(const struct clk_hw *hw);
bool clk_hw_rate_is_protected(const struct clk_hw *hw);
bool clk_hw_is_enabled(const struct clk_hw *hw);
--
2.7.4