@@ -662,12 +662,15 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
status |= USB_PORT_STAT_SUSPEND;
}
}
- if ((raw_port_status & PORT_PLS_MASK) == XDEV_U0
- && (raw_port_status & PORT_POWER)
- && (bus_state->suspended_ports & (1 << wIndex))) {
- bus_state->suspended_ports &= ~(1 << wIndex);
- if (hcd->speed != HCD_USB3)
- bus_state->port_c_suspend |= 1 << wIndex;
+ if ((raw_port_status & PORT_PLS_MASK) == XDEV_U0 &&
+ (raw_port_status & PORT_POWER)) {
+ if (bus_state->suspended_ports & (1 << wIndex)) {
+ bus_state->suspended_ports &= ~(1 << wIndex);
+ if (hcd->speed != HCD_USB3)
+ bus_state->port_c_suspend |= 1 << wIndex;
+ }
+ bus_state->resume_done[wIndex] = 0;
+ clear_bit(wIndex, &bus_state->resuming_ports);
}
if (raw_port_status & PORT_CONNECT) {
status |= USB_PORT_STAT_CONNECTION;
This is a note to let you know that I have just added a patch titled xhci: Fix a race in usb2 LPM resume, blocking U3 for usb2 devices to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11-ckt32. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From f7db3e0c74a2b28e3feef66cba865f0e28b4d0ab Mon Sep 17 00:00:00 2001 From: Mathias Nyman <mathias.nyman@linux.intel.com> Date: Wed, 18 Nov 2015 10:48:22 +0200 Subject: xhci: Fix a race in usb2 LPM resume, blocking U3 for usb2 devices commit dad67d5f3d0efe01d38c6cebcb6698280e51927b upstream. Clear device initiated resume variables once device is fully up and running in U0 state. Resume needs to be signaled for 20ms for usb2 devices before they can be moved to U0 state. An interrupt is triggered if a device initiates resume. As we handle the event in interrupt context we can not sleep for 20ms, so we instead set a resume flag, a timestamp, and start the roothub polling. The roothub code will later move the port to U0 when it finds a port in resume state with the resume flag set, and timestamp passed by 20ms. A host initiated resume is however not done in interrupt context, and host initiated resume code will directly signal resume, wait 20ms and then move the port to U0. These two codepaths can race, if we are in the middle of a host initated resume, while sleeping for 20ms, we may handle a port event and find the port in resume state. The port event handling code will assume the resume was device initiated and set the resume flag and timestamp. Root hub code will however not catch the port in resume state again as the host initated resume code has already moved the port to U0. The resume flag and timestamp will remain set for this port preventing port from suspending again (LPM setting port to U3) Fix this for now by always clearing the device initated resume parameters once port is in U0 Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/usb/host/xhci-hub.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) -- 1.9.1