[PATCH 5.15.y] usb: roles: get usb role switch from parent only for usb-b-connector

[Sasha Levin <sashal@kernel.org>]

From: Xu Yang <xu.yang_2@nxp.com>

[ Upstream commit 8345b1539faa49fcf9c9439c3cbd97dac6eca171 ]

usb_role_switch_is_parent() was walking up to the parent node and checking
for the "usb-role-switch" property regardless of the type of the passed
fwnode. This could cause unrelated device nodes to be probed as potential
role switch parent, leading to spurious matches and "-EPROBE_DEFER" being
returned infinitely.

Till now only Type-B connector node will have a parent node which may
present "usb-role-switch" property and register the role switch device.
For Type-C connector node, its parent node will always be a Type-C chip
device which will never register the role switch device. However, it may
still present a non-boolean "usb-role-switch = <&usb_controller>" property
for historical compatibility.

So restrict the helper to only operate on Type-B connector when attempting
to get the role switch from parent node.

Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent")
Cc: stable <stable@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Tested-by: Arnaud Ferraris <arnaud.ferraris@collabora.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20260309074313.2809867-3-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ replace fwnode_device_is_compatible() call with it's expansion ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/roles/class.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
index 917dffe9aee54..79c068c537934 100644
--- a/drivers/usb/roles/class.c
+++ b/drivers/usb/roles/class.c
@@ -108,9 +108,14 @@ static void *usb_role_switch_match(struct fwnode_handle *fwnode, const char *id,
 static struct usb_role_switch *
 usb_role_switch_is_parent(struct fwnode_handle *fwnode)
 {
-	struct fwnode_handle *parent = fwnode_get_parent(fwnode);
+	struct fwnode_handle *parent;
 	struct device *dev;
 
+	if (fwnode_property_match_string(fwnode, "compatible", "usb-b-connector") < 0)
+		return NULL;
+
+	parent = fwnode_get_parent(fwnode);
+
 	if (!fwnode_property_present(parent, "usb-role-switch")) {
 		fwnode_handle_put(parent);
 		return NULL;
-- 
2.51.0