usb: ohci-at91: Do not drop unhandled USB suspend control requests

commit 85550f91 upstream.

In patch 2e2aa1bcm, USB suspend and wakeup control requests are
passed to SFR_OHCIICR register. If a processor does not have such a
register, this hub control request will be dropped.

If no such a SFR register is available, all USB suspend control requests
will now be processed using ohci_hub_control()
(like before patch 2e2aa1bcm.)

Tested on an Atmel AT91SAM9G20 with an on-board TI TUSB2046B hub chip
If the last USB device is unplugged from the USB hub, the hub goes into
sleep and will not wakeup when an USB devices is inserted.

Fixes: 2e2aa1bc ("usb: ohci-at91: Forcibly suspend ports while USB suspend")
Signed-off-by: Jelle Martijn Kok <jmkok@youcom.nl>
Tested-by: Wenyou Yang <wenyou.yang@atmel.com>
Cc: Wenyou Yang <wenyou.yang@atmel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ohci-at91.c

@@ -350,7 +350,7 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 
 		case USB_PORT_FEAT_SUSPEND:
 			dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
-			if (valid_port(wIndex)) {
+			if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 				ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 						       1);
 				return 0;
@@ -393,7 +393,7 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 
 		case USB_PORT_FEAT_SUSPEND:
 			dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
-			if (valid_port(wIndex)) {
+			if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 				ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 						       0);
 				return 0;