patch "xhci: Identify USB 3.1 capable hosts by their port protocol" added to usb-linus

patch "xhci: Identify USB 3.1 capable hosts by their port protocol" added to usb-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    xhci: Identify USB 3.1 capable hosts by their port protocol

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From ea7d0d69426cab6747ed311c53f4142eb48b9454 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Fri, 6 Oct 2017 17:45:27 +0300
Subject: xhci: Identify USB 3.1 capable hosts by their port protocol
 capability

Many USB 3.1 capable hosts never updated the Serial Bus Release Number
(SBRN) register to USB 3.1 from USB 3.0

xhci driver identified USB 3.1 capable hosts based on this SBRN register,
which according to specs "contains the release of the Universal Serial
Bus Specification with which this Universal Serial Bus Host Controller
module is compliant." but still in october 2017 gives USB 3.0 as
the only possible option.

Make an additional check for USB 3.1 support and enable it if the xHCI
supported protocol capablity lists USB 3.1 capable ports.

Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index ee198ea47f49..51535ba2bcd4 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4805,7 +4805,8 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 		 */
 		hcd->has_tt = 1;
 	} else {
-		if (xhci->sbrn == 0x31) {
+		/* Some 3.1 hosts return sbrn 0x30, can't rely on sbrn alone */
+		if (xhci->sbrn == 0x31 || xhci->usb3_rhub.min_rev >= 1) {
 			xhci_info(xhci, "Host supports USB 3.1 Enhanced SuperSpeed\n");
 			hcd->speed = HCD_USB31;
 			hcd->self.root_hub->speed = USB_SPEED_SUPER_PLUS;
-- 
2.14.2