[PATCH 3/3] usb: typec: Connect Type-C port with associated USB4 port

Alan Borzeszkowski
2025-04-14T17:56:07Z

If USB3.x device references USB4 host interface, USB4 port can be
connected with appropriate Type-C port. By using component framework,
and in turn by creating symlinks, userspace can benefit from having
Thunderbolt/USB4 connection to Type-C ports.

Note: This change introduces dependency on Thunderbolt driver as it's
required to properly map USB4 port to Type-C port.

Signed-off-by: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
---
drivers/usb/typec/port-mapper.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/port-mapper.c b/drivers/usb/typec/port-mapper.c
index d42da5720a25..cdbb7c11d714 100644
--- a/drivers/usb/typec/port-mapper.c
+++ b/drivers/usb/typec/port-mapper.c
@@ -8,6 +8,7 @@

#include <linux/acpi.h>
#include <linux/component.h>
+#include <linux/thunderbolt.h>
#include <linux/usb.h>

#include "class.h"
@@ -36,6 +37,11 @@ struct each_port_arg {
struct component_match *match;
};

+static int usb4_port_compare(struct device *dev, void *fwnode)
+{
+ return usb4_usb3_port_match(dev, fwnode);
+}
+
static int typec_port_compare(struct device *dev, void *fwnode)
{
return device_match_fwnode(dev, fwnode);
@@ -51,9 +57,22 @@ static int typec_port_match(struct device *dev, void *data)
if (con_adev == adev)
return 0;

- if (con_adev->pld_crc == adev->pld_crc)
+ if (con_adev->pld_crc == adev->pld_crc) {
+ struct fwnode_handle *adev_fwnode = acpi_fwnode_handle(adev);
+
component_match_add(&arg->port->dev, &arg->match, typec_port_compare,
- acpi_fwnode_handle(adev));
+ adev_fwnode);
+
+ /*
+ * If dev is USB 3.x port, it may have reference to the
+ * USB4 host interface in which case we can also link the
+ * Type-C port with the USB4 port.
+ */
+ if (fwnode_property_present(adev_fwnode, "usb4-host-interface"))
+ component_match_add(&arg->port->dev, &arg->match,
+ usb4_port_compare, adev_fwnode);
+ }
+
return 0;
}

--
2.43.0