From: Kai-Heng Feng kai.heng.feng@canonical.com

Sometimes re-plugging a USB device during system sleep renders the device useless: [ 173.418345] xhci_hcd 0000:00:14.0: Get port status 2-4 read: 0x14203e2, return 0x10262 ... [ 176.496485] usb 2-4: Waited 2000ms for CONNECT [ 176.496781] usb usb2-port4: status 0000.0262 after resume, -19 [ 176.497103] usb 2-4: can't resume, status -19 [ 176.497438] usb usb2-port4: logical disconnect

Because PLS equals to XDEV_RESUME, xHCI driver reports U3 to usbcore, despite of CAS bit is flagged.

So proritize CAS over XDEV_RESUME to let usbcore handle warm-reset for the port.

Cc: stable stable@vger.kernel.org Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com --- drivers/usb/host/xhci-hub.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index c3554e37e09f..4e14e164cb68 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -740,15 +740,6 @@ static void xhci_hub_report_usb3_link_state(struct xhci_hcd *xhci, { u32 pls = status_reg & PORT_PLS_MASK;

- /* resume state is a xHCI internal state. - * Do not report it to usb core, instead, pretend to be U3, - * thus usb core knows it's not ready for transfer - */ - if (pls == XDEV_RESUME) { - *status |= USB_SS_PORT_LS_U3; - return; - } - /* When the CAS bit is set then warm reset * should be performed on port */ @@ -770,6 +761,16 @@ static void xhci_hub_report_usb3_link_state(struct xhci_hcd *xhci, */ pls |= USB_PORT_STAT_CONNECTION; } else { + /* + * Resume state is an xHCI internal state. Do not report it to + * usb core, instead, pretend to be U3, thus usb core knows + * it's not ready for transfer. + */ + if (pls == XDEV_RESUME) { + *status |= USB_SS_PORT_LS_U3; + return; + } + /* * If CAS bit isn't set but the Port is already at * Compliance Mode, fake a connection so the USB core