Merge "usb: xhci: Support enabling of compliance mode for xhci 1.1"

drivers/usb/host/xhci-hub.c

@@ -1197,6 +1197,40 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 				temp = readl(port_array[wIndex]);
 				break;
 			}
+
+			/*
+			 * For xHCI 1.1 according to section 4.19.1.2.4.1 a
+			 * root hub port's transition to compliance mode upon
+			 * detecting LFPS timeout may be controlled by an
+			 * Compliance Transition Enabled (CTE) flag (not
+			 * software visible). This flag is set by writing 0xA
+			 * to PORTSC PLS field which will allow transition to
+			 * compliance mode the next time LFPS timeout is
+			 * encountered. A warm reset will clear it.
+			 *
+			 * The CTE flag is only supported if the HCCPARAMS2 CTC
+			 * flag is set, otherwise, the compliance substate is
+			 * automatically entered as on 1.0 and prior.
+			 */
+			if (link_state == USB_SS_PORT_LS_COMP_MOD) {
+				if (!HCC2_CTC(xhci->hcc_params2)) {
+					xhci_dbg(xhci, "CTC flag is 0, port already supports entering compliance mode\n");
+					break;
+				}
+
+				if ((temp & PORT_CONNECT)) {
+					xhci_warn(xhci, "Can't set compliance mode when port is connected\n");
+					goto error;
+				}
+
+				xhci_dbg(xhci, "Enable compliance mode transition for port %d\n",
+						wIndex);
+				xhci_set_link_state(xhci, port_array, wIndex,
+						link_state);
+				temp = readl(port_array[wIndex]);
+				break;
+			}
+
 			/* Port must be enabled */
 			if (!(temp & PORT_PE)) {
 				retval = -ENODEV;