[PATCH v6 01/14] dm: core: Add function to get child count of ofnode or device

[Chunfeng Yun <chunfeng.yun@mediatek.com>]

This patch add function used to get the child count of
a ofnode or a device

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Weijie Gao <weijie.gao@mediatek.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
v6: add Reviewed-by Weijie & Simon

v4~v5: no changes

v3:
    1. add non/inline function dev_get_child_count() instead of macro suggested by Simon

v2:
    1. move ofnode_get_child_count() into ofnode.c suggested by Simon
    2. add a new macro dev_get_child_count()
---
 drivers/core/ofnode.c | 11 +++++++++++
 drivers/core/read.c   |  5 +++++
 include/dm/ofnode.h   |  8 ++++++++
 include/dm/read.h     | 13 +++++++++++++
 4 files changed, 37 insertions(+)

diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
index 20871a6815..e3c42dae5c 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -474,6 +474,17 @@ ofnode ofnode_get_chosen_node(const char *name)
 	return ofnode_path(prop);
 }
 
+int ofnode_get_child_count(ofnode parent)
+{
+	ofnode child;
+	int num = 0;
+
+	ofnode_for_each_subnode(child, parent)
+		num++;
+
+	return num;
+}
+
 static int decode_timing_property(ofnode node, const char *name,
 				  struct timing_entry *result)
 {
diff --git a/drivers/core/read.c b/drivers/core/read.c
index 47b8e03446..3d421f7a69 100644
--- a/drivers/core/read.c
+++ b/drivers/core/read.c
@@ -352,3 +352,8 @@ fdt_addr_t dev_read_addr_pci(const struct udevice *dev)
 
 	return addr;
 }
+
+int dev_get_child_count(const struct udevice *dev)
+{
+	return ofnode_get_child_count(dev_ofnode(dev));
+}
diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
index 618fc10390..a0d3df7786 100644
--- a/include/dm/ofnode.h
+++ b/include/dm/ofnode.h
@@ -879,6 +879,14 @@ ofnode ofnode_by_prop_value(ofnode from, const char *propname,
 	     ofnode_valid(node); \
 	     node = ofnode_next_subnode(node))
 
+/**
+ * ofnode_get_child_count() - get the child count of a ofnode
+ *
+ * @node: valid node to get its child count
+ * @return the number of subnodes
+ */
+int ofnode_get_child_count(ofnode parent);
+
 /**
  * ofnode_translate_address() - Translate a device-tree address
  *
diff --git a/include/dm/read.h b/include/dm/read.h
index 03c15b8550..b952551d55 100644
--- a/include/dm/read.h
+++ b/include/dm/read.h
@@ -669,6 +669,14 @@ u64 dev_translate_dma_address(const struct udevice *dev,
  */
 int dev_read_alias_highest_id(const char *stem);
 
+/**
+ * dev_get_child_count() - get the child count of a device
+ *
+ * @dev: device to use for interation (struct udevice *)
+ * @return the count of child subnode
+ */
+int dev_get_child_count(const struct udevice *dev);
+
 #else /* CONFIG_DM_DEV_READ_INLINE is enabled */
 
 static inline int dev_read_u32(const struct udevice *dev,
@@ -978,6 +986,11 @@ static inline int dev_read_alias_highest_id(const char *stem)
 	return fdtdec_get_alias_highest_id(gd->fdt_blob, stem);
 }
 
+static inline int dev_get_child_count(const struct udevice *dev)
+{
+	return ofnode_get_child_count(dev_ofnode(dev));
+}
+
 #endif /* CONFIG_DM_DEV_READ_INLINE */
 
 /**
-- 
2.25.1