[PATCH v1] drivers property: When no children in primary, try secondary

[Andy Shevchenko]

Software firmware nodes can provide a child node to its parent.
Since software node can be secondary, we need a mechanism to access
the children. The idea is to list children of the primary node first
and when they are finished, continue with secondary node if available.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/base/property.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 5f35c0ccf5e0..1e6d75e65938 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -708,14 +708,23 @@ struct fwnode_handle *device_get_next_child_node(struct device *dev,
 						 struct fwnode_handle *child)
 {
 	struct acpi_device *adev = ACPI_COMPANION(dev);
-	struct fwnode_handle *fwnode = NULL;
+	struct fwnode_handle *fwnode = NULL, *next;
 
 	if (dev->of_node)
 		fwnode = &dev->of_node->fwnode;
 	else if (adev)
 		fwnode = acpi_fwnode_handle(adev);
 
-	return fwnode_get_next_child_node(fwnode, child);
+	/* Try to find a child in primary fwnode */
+	next = fwnode_get_next_child_node(fwnode, child);
+	if (next)
+		return next;
+
+	/* When no more children in primary, continue with secondary */
+	if (!IS_ERR_OR_NULL(fwnode->secondary))
+		next = fwnode_get_next_child_node(fwnode->secondary, child);
+
+	return next;
 }
 EXPORT_SYMBOL_GPL(device_get_next_child_node);
 
-- 
2.26.2