From: Kai-Heng Feng kai.heng.feng@canonical.com
commit 904df64a5f4d5ebd670801d869ca0a6d6a6e8df6 upstream.
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 Link: https://lore.kernel.org/r/20200821091549.20556-3-mathias.nyman@linux.intel.c... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/host/xhci-hub.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)
--- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -623,15 +623,6 @@ static void xhci_hub_report_usb3_link_st { 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 */ @@ -654,6 +645,16 @@ static void xhci_hub_report_usb3_link_st 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 * notices the Compliance state and resets the port.