From: Michael Brown <mcb30@ipxe.org>
Date: Thu, 2 Jul 2020 21:53:11 +0000 (+0100)
Subject: [xhci] Set link state to RxDetect after disabling USB3 root hub port
X-Git-Tag: v1.21.1~136
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18d4be8aafe9ea468daed907aca3fd730e8c0d2e;p=thirdparty%2Fipxe.git

[xhci] Set link state to RxDetect after disabling USB3 root hub port

The "disabled" port states for USB2 and USB3 are not directly
equivalent.  In particular, a disabled USB3 port will not detect new
device connections.  The result is that a USB3 device disconnected
from and reconnected to an xHCI root hub port will end up reconnecting
as a USB2 device.

Fix by setting the link state to RxDetect after disabling the port, as
is already done during initialisation.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/drivers/usb/xhci.c b/src/drivers/usb/xhci.c
index e9a7f4c65..21c3e0001 100644
--- a/src/drivers/usb/xhci.c
+++ b/src/drivers/usb/xhci.c
@@ -3051,6 +3051,19 @@ static int xhci_root_disable ( struct usb_hub *hub, struct usb_port *port ) {
 	portsc |= XHCI_PORTSC_PED;
 	writel ( portsc, xhci->op + XHCI_OP_PORTSC ( port->address ) );
 
+	/* Allow time for link state to stabilise */
+	mdelay ( XHCI_LINK_STATE_DELAY_MS );
+
+	/* Set link state to RxDetect for USB3 ports */
+	if ( port->protocol >= USB_PROTO_3_0 ) {
+		portsc &= XHCI_PORTSC_PRESERVE;
+		portsc |= ( XHCI_PORTSC_PLS_RXDETECT | XHCI_PORTSC_LWS );
+		writel ( portsc, xhci->op + XHCI_OP_PORTSC ( port->address ) );
+	}
+
+	/* Allow time for link state to stabilise */
+	mdelay ( XHCI_LINK_STATE_DELAY_MS );
+
 	return 0;
 }