usb: typec: ucsi: Only set number of plug altmodes after registration

Move the setting of the plug's number of alternate modes into the
same condition as the plug's registration to prevent dereferencing the
connector's plug pointer while it is null.

Fixes: c313a44 ("usb: typec: ucsi: Always set number of alternate modes")
Suggested-by: Jon Hunter <[email protected]>
Signed-off-by: Jameson Thies <[email protected]>
Reviewed-by: Benson Leung <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Tested-by: Jon Hunter <[email protected]>
Reviewed-by: Jon Hunter <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: jthiesatgoogle

drivers/usb/typec/ucsi/ucsi.c

@@ -1180,13 +1180,13 @@ static int ucsi_check_cable(struct ucsi_connector *con)
 		ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP_P);
 		if (ret < 0)
 			return ret;
-	}
 
-	if (con->plug_altmode[0]) {
-		num_plug_am = ucsi_get_num_altmode(con->plug_altmode);
-		typec_plug_set_num_altmodes(con->plug, num_plug_am);
-	} else {
-		typec_plug_set_num_altmodes(con->plug, 0);
+		if (con->plug_altmode[0]) {
+			num_plug_am = ucsi_get_num_altmode(con->plug_altmode);
+			typec_plug_set_num_altmodes(con->plug, num_plug_am);
+		} else {
+			typec_plug_set_num_altmodes(con->plug, 0);
+		}
 	}
 
 	return 0;