usb: dwc2: hcd: Fix GetPortStatus & SetPortFeature

On Rasperry Pis without onboard USB hub the power cycle during
power connect init only disable the port but never enabled it again:

usb usb1-port1: attempt power cycle

The port relevant part in dwc2_hcd_hub_control() is skipped in case
port_connect_status = 0 under the assumption the core is or will be soon
in device mode. But this assumption is wrong, because after ClearPortFeature
USB_PORT_FEAT_POWER the port_connect_status will also be 0 and
SetPortFeature (incl. USB_PORT_FEAT_POWER) will be a no-op.

Fix the behavior of dwc2_hcd_hub_control() by replacing the
port_connect_status check with dwc2_is_device_mode().

Link: https://github.com/raspberrypi/linux/issues/6247
Fixes: 7359d482eb4d ("staging: HCD files for the DWC2 driver")
Signed-off-by: Stefan Wahren <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/dwc2/hcd.c

···
 			port_status |= USB_PORT_STAT_C_OVERCURRENT << 16;
 		}
 
-		if (!hsotg->flags.b.port_connect_status) {
+		if (dwc2_is_device_mode(hsotg)) {
 			/*
-			 * The port is disconnected, which means the core is
-			 * either in device mode or it soon will be. Just
-			 * return 0's for the remainder of the port status
+			 * Just return 0's for the remainder of the port status
 			 * since the port register can't be read if the core
 			 * is in device mode.
 			 */
···
 		if (wvalue != USB_PORT_FEAT_TEST && (!windex || windex > 1))
 			goto error;
 
-		if (!hsotg->flags.b.port_connect_status) {
+		if (dwc2_is_device_mode(hsotg)) {
 			/*
-			 * The port is disconnected, which means the core is
-			 * either in device mode or it soon will be. Just
-			 * return without doing anything since the port
-			 * register can't be written if the core is in device
-			 * mode.
+			 * Just return 0's for the remainder of the port status
+			 * since the port register can't be read if the core
+			 * is in device mode.
 			 */
 			break;
 		}