usb: dwc2: Add part. power down exit from dwc2_conn_id_status_change().

Before changing to connector B exiting from Partial
Power Down is required.

- Added exiting from Partial Power Down mode when
  connector ID status changes to "connId B".
  Because if connector ID status changed to B connector
  while core was in partial power down mode, HANG would
  accrue from a soft reset.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210408094534.4AA7AA022E@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Artur Petrosyan

drivers/usb/dwc2/hcd.c

@@ -3206,6 +3206,15 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
 		if (count > 250)
 			dev_err(hsotg->dev,
 				"Connection id status change timed out\n");
+
+		/*
+		 * Exit Partial Power Down without restoring registers.
+		 * No need to check the return value as registers
+		 * are not being restored.
+		 */
+		if (hsotg->in_ppd && hsotg->lx_state == DWC2_L2)
+			dwc2_exit_partial_power_down(hsotg, 0, false);
+
 		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
 		dwc2_core_init(hsotg, false);
 		dwc2_enable_global_interrupts(hsotg);