+ vt8500_port->uart.membase = devm_request_and_ioremap(&pdev->dev, mmres);
+ if (!vt8500_port->uart.membase)
+ return -EADDRNOTAVAIL;
+
+ vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(vt8500_port->clk)) {
+ dev_err(&pdev->dev, "failed to get clock\n");
+ return -EINVAL;
+ }
+
+ ret = clk_prepare_enable(vt8500_port->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable clock\n");
+ return ret;
+ }
+