thunderbolt: Introduce tb_port_is_nhi()

This is useful if one needs to check if adapter (port) is the host
interface (NHI). Make tb_port_alloc_hopid() take advantage of this.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/thunderbolt/switch.c

@@ -789,7 +789,7 @@ static int tb_port_alloc_hopid(struct tb_port *port, bool in, int min_hopid,
 	 * NHI can use HopIDs 1-max for other adapters HopIDs 0-7 are
 	 * reserved.
 	 */
-	if (port->config.type != TB_TYPE_NHI && min_hopid < TB_PATH_MIN_HOPID)
+	if (!tb_port_is_nhi(port) && min_hopid < TB_PATH_MIN_HOPID)
 		min_hopid = TB_PATH_MIN_HOPID;
 
 	if (max_hopid < 0 || max_hopid > port_max_hopid)

drivers/thunderbolt/tb.h

@@ -464,6 +464,11 @@ static inline bool tb_port_is_null(const struct tb_port *port)
 	return port && port->port && port->config.type == TB_TYPE_PORT;
 }
 
+static inline bool tb_port_is_nhi(const struct tb_port *port)
+{
+	return port && port->config.type == TB_TYPE_NHI;
+}
+
 static inline bool tb_port_is_pcie_down(const struct tb_port *port)
 {
 	return port && port->config.type == TB_TYPE_PCIE_DOWN;