if (err)
                goto err1;
 
-       if (!request_mem_region(res->start, resource_size(res),
-                               ehci_orion_hc_driver.description)) {
-               dev_dbg(&pdev->dev, "controller already in use\n");
-               err = -EBUSY;
+       regs = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(regs)) {
+               err = PTR_ERR(regs);
                goto err1;
        }
 
-       regs = ioremap(res->start, resource_size(res));
-       if (regs == NULL) {
-               dev_dbg(&pdev->dev, "error mapping memory\n");
-               err = -EFAULT;
-               goto err2;
-       }
-
        /* Not all platforms can gate the clock, so it is not
           an error if the clock does not exists. */
-       clk = clk_get(&pdev->dev, NULL);
-       if (!IS_ERR(clk)) {
+       clk = devm_clk_get(&pdev->dev, NULL);
+       if (!IS_ERR(clk))
                clk_prepare_enable(clk);
-               clk_put(clk);
-       }
 
        hcd = usb_create_hcd(&ehci_orion_hc_driver,
                        &pdev->dev, dev_name(&pdev->dev));
        if (!hcd) {
                err = -ENOMEM;
-               goto err3;
+               goto err2;
        }
 
        hcd->rsrc_start = res->start;
 
        err = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (err)
-               goto err4;
+               goto err3;
 
        device_wakeup_enable(hcd->self.controller);
        return 0;
 
-err4:
-       usb_put_hcd(hcd);
 err3:
-       if (!IS_ERR(clk)) {
-               clk_disable_unprepare(clk);
-               clk_put(clk);
-       }
-       iounmap(regs);
+       usb_put_hcd(hcd);
 err2:
-       release_mem_region(res->start, resource_size(res));
+       if (!IS_ERR(clk))
+               clk_disable_unprepare(clk);
 err1:
        dev_err(&pdev->dev, "init %s fail, %d\n",
                dev_name(&pdev->dev), err);
        struct clk *clk;
 
        usb_remove_hcd(hcd);
-       iounmap(hcd->regs);
-       release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
        usb_put_hcd(hcd);
 
-       clk = clk_get(&pdev->dev, NULL);
-       if (!IS_ERR(clk)) {
+       clk = devm_clk_get(&pdev->dev, NULL);
+       if (!IS_ERR(clk))
                clk_disable_unprepare(clk);
-               clk_put(clk);
-       }
        return 0;
 }