[PATCH 5.3 036/112] usb: typec: tcpm: usb: typec: tcpm: Fix a signedness bug in tcpm_fw_get_caps()

[Greg Kroah-Hartman]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 7101949f36fc77b530b73e4c6bd0066a2740d75b upstream.

The "port->typec_caps.data" and "port->typec_caps.type" variables are
enums and in this context GCC will treat them as an unsigned int so they
can never be less than zero.

Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20191001120117.GA23528@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/typec/tcpm/tcpm.c |   14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4416,18 +4416,20 @@ static int tcpm_fw_get_caps(struct tcpm_
 	/* USB data support is optional */
 	ret = fwnode_property_read_string(fwnode, "data-role", &cap_str);
 	if (ret == 0) {
-		port->typec_caps.data = typec_find_port_data_role(cap_str);
-		if (port->typec_caps.data < 0)
-			return -EINVAL;
+		ret = typec_find_port_data_role(cap_str);
+		if (ret < 0)
+			return ret;
+		port->typec_caps.data = ret;
 	}
 
 	ret = fwnode_property_read_string(fwnode, "power-role", &cap_str);
 	if (ret < 0)
 		return ret;
 
-	port->typec_caps.type = typec_find_port_power_role(cap_str);
-	if (port->typec_caps.type < 0)
-		return -EINVAL;
+	ret = typec_find_port_power_role(cap_str);
+	if (ret < 0)
+		return ret;
+	port->typec_caps.type = ret;
 	port->port_type = port->typec_caps.type;
 
 	if (port->port_type == TYPEC_PORT_SNK)