--- zzzz-none-000/linux-4.4.271/drivers/usb/host/xhci-mem.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/drivers/usb/host/xhci-mem.c	2023-04-19 10:22:30.000000000 +0000
@@ -442,6 +442,12 @@
 		seg = seg->next;
 	} while (seg != ring->first_seg);
 	ring->type = type;
+
+	/* 20171011 AVM/VGJ Fix: set link toggle bit for last segment
+	 * Taken from xhci_ring_alloc */
+	ring->last_seg->trbs[TRBS_PER_SEGMENT - 1].link.control |=
+		cpu_to_le32(LINK_TOGGLE);
+
 	xhci_initialize_ring_info(ring, cycle_state);
 	/* td list should be empty since all URBs have been cancelled,
 	 * but just in case...
@@ -1094,6 +1100,12 @@
 	virt_dev = xhci->devs[udev->slot_id];
 	ep0_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, 0);
 	ep_ring = virt_dev->eps[0].ring;
+
+	/* == AVM/WKR 20170329 : USB Reset Workaround ==
+	 *    Avoid AddressDevice error on quirky hosts by flushing of EP0 ring
+	 */
+	xhci_reinit_cached_ring(xhci, ep_ring, 1, TYPE_CTRL);
+
 	/*
 	 * FIXME we don't keep track of the dequeue pointer very well after a
 	 * Set TR dequeue pointer, so we're setting the dequeue pointer of the
@@ -2206,11 +2218,15 @@
 		xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 				"xHCI 1.0: support USB2 software lpm");
 		xhci->sw_lpm_support = 1;
+
+#if !defined(CONFIG_AVM_KERNEL)
+/*== 20180705 AVM/WKR WA: do not allow USB2 HW LPM for AVM ==*/
 		if (temp & XHCI_HLC) {
 			xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 					"xHCI 1.0: support USB2 hardware lpm");
 			xhci->hw_lpm_support = 1;
 		}
+#endif
 	}
 
 	port_offset--;