[PATCH 3/3] xhci: Show zhaoxin xHCI root hub speed correctly

[Weitao Wang]

Some zhaoxin xHCI controllers follow usb3.1 spec,
but only support gen1 speed 5G. While in Linux kernel,
if xHCI suspport usb3.1,root hub speed will show on 10G.
To fix this issue of zhaoxin xHCI platforms, read usb speed ID
supported by xHCI to determine root hub speed.

Signed-off-by: Weitao Wang <WeitaoWang-oc@xxxxxxxxxxx>
---
 drivers/usb/host/xhci.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 730c0f68518d..60b17799aa88 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -5317,6 +5317,7 @@ static void xhci_hcd_init_usb2_data(struct xhci_hcd *xhci, struct usb_hcd *hcd)
 static void xhci_hcd_init_usb3_data(struct xhci_hcd *xhci, struct usb_hcd *hcd)
 {
 	unsigned int minor_rev;
+	unsigned int i, j;
 
 	/*
 	 * Early xHCI 1.1 spec did not mention USB 3.1 capable hosts
@@ -5346,6 +5347,27 @@ static void xhci_hcd_init_usb3_data(struct xhci_hcd *xhci, struct usb_hcd *hcd)
 		hcd->self.root_hub->ssp_rate = USB_SSP_GEN_2x1;
 		break;
 	}
+
+	/* Usb3.1 has gen1 and gen2, Some zhaoxin's xHCI controller
+	 * that follow usb3.1 spec but only support gen1.
+	 */
+	if (xhci->quirks & XHCI_ZHAOXIN_HOST) {
+		minor_rev = 0;
+		for (j = 0; j < xhci->num_port_caps; j++) {
+			for (i = 0; i < xhci->port_caps[j].psi_count; i++) {
+				if (XHCI_EXT_PORT_PSIV(xhci->port_caps[j].psi[i]) >= 5) {
+					minor_rev = 1;
+					break;
+				}
+			}
+			if (minor_rev)
+				break;
+		}
+		if (minor_rev != 1) {
+			hcd->speed = HCD_USB3;
+			hcd->self.root_hub->speed = USB_SPEED_SUPER;
+		}
+	}
 	xhci_info(xhci, "Host supports USB 3.%x %sSuperSpeed\n",
 		  minor_rev, minor_rev ? "Enhanced " : "");
 
-- 
2.32.0