usb: host: ohci-platform: enable async suspend for rk3588

The rk3588 has two ohci controllers, and the ohci_resume()
takes a long time when system resume. Considering that the
delay time in the ohci_resume() is related to controller
hardware, we should not modify the delay time.

This patch enable async suspend for rk3588 ohci controllers,
then they can do asynchronous resume. Note that it generally
is unsafe to permit the asynchronous suspend/resume for ohci
because we can't certain that the PM dependencies of the ohci.
However, for rk3588, we have add device_link between the ohci
and ehci with the commit 68850661b5 ("usb: host: ehci-platform:
Add device_link between the ehci and companion"), so we can
safely enable async suspend/resume for rk3588 ohci.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Change-Id: Ia74fc59c2c75a4bdc34d0de0a7bd047c178e9971

drivers/usb/host/ohci-platform.c

@@ -216,6 +216,10 @@ static int ohci_platform_probe(struct platform_device *dev)
 
 	device_wakeup_enable(hcd->self.controller);
 
+	if (of_device_is_compatible(dev->dev.of_node,
+				    "rockchip,rk3588-ohci"))
+		device_enable_async_suspend(hcd->self.controller);
+
 	platform_set_drvdata(dev, hcd);
 
 	return err;