device property: Split fwnode_get_child_node_count()

The new helper is introduced to allow counting the child firmware nodes
of their parent without requiring a device to be passed. This also makes
the fwnode and device property API more symmetrical with the rest.

Signed-off-by: Andy Shevchenko <[e-mail]>
Acked-by: "Rafael J. Wysocki" <[e-mail]>
Reviewed-by: Sakari Ailus <[e-mail]>
Reviewed-by: Heikki Krogerus <[e-mail]>
Reviewed-by: Jonathan Cameron <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Lee Jones <[e-mail]>

drivers/base/property.c

···
 EXPORT_SYMBOL_GPL(fwnode_device_is_available);
 
 /**
- * device_get_child_node_count - return the number of child nodes for device
- * @dev: Device to count the child nodes for
+ * fwnode_get_child_node_count - return the number of child nodes for a given firmware node
+ * @fwnode: Pointer to the parent firmware node
  *
- * Return: the number of child nodes for a given device.
+ * Return: the number of child nodes for a given firmware node.
  */
-unsigned int device_get_child_node_count(const struct device *dev)
+unsigned int fwnode_get_child_node_count(const struct fwnode_handle *fwnode)
 {
 	struct fwnode_handle *child;
 	unsigned int count = 0;
 
-	device_for_each_child_node(dev, child)
+	fwnode_for_each_child_node(fwnode, child)
 		count++;
 
 	return count;
 }
-EXPORT_SYMBOL_GPL(device_get_child_node_count);
+EXPORT_SYMBOL_GPL(fwnode_get_child_node_count);
 
 bool device_dma_supported(const struct device *dev)
 {

include/linux/property.h

···
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
 int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name);
 
-unsigned int device_get_child_node_count(const struct device *dev);
+unsigned int fwnode_get_child_node_count(const struct fwnode_handle *fwnode);
+
+static inline unsigned int device_get_child_node_count(const struct device *dev)
+{
+	return fwnode_get_child_node_count(dev_fwnode(dev));
+}
 
 static inline int device_property_read_u8(const struct device *dev,
 					  const char *propname, u8 *val)