From ea7d0d69426cab6747ed311c53f4142eb48b9454 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Fri, 6 Oct 2017 17:45:27 +0300 Subject: [PATCH] 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: # v4.6+ Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- 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 ee198ea..51535ba 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; -- 2.7.4