ACPI: device property: Fix node lookup in acpi_graph_get_child_prop_value()

commit b5212f57da145e53df790a7e211d94daac768bf8 upstream.

acpi_graph_get_child_prop_value() is intended to find a child node with a
certain property value pair. The check

	if (!fwnode_property_read_u32(fwnode, prop_name, &nr))
		continue;

is faulty: fwnode_property_read_u32() returns zero on success, not on
failure, leading to comparing values only if the searched property was not
found.

Moreover, the check is made against the parent device node instead of
the child one as it should be.

Fixes: 79389a83bc38 (ACPI / property: Add support for remote endpoints)
Reported-by: Hyungwoo Yang <hyungwoo.yang@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 9364398204e91b23958eef08d306771f7d4cbd92..6822ac9f106ba6f42c081dc88b68cd173e5e8ce3 100644 (file)
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -1046,7 +1046,7 @@ static struct fwnode_handle *acpi_graph_get_child_prop_value(
        fwnode_for_each_child_node(fwnode, child) {
                u32 nr;
 
-               if (!fwnode_property_read_u32(fwnode, prop_name, &nr))
+               if (fwnode_property_read_u32(child, prop_name, &nr))
                        continue;
 
                if (val == nr)