From f69e3120df82391a0ee8118e0a156239a06b2afb Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Thu, 3 Nov 2011 11:37:10 -0400 Subject: [PATCH] USB: XHCI: resume root hubs when the controller resumes This patch (as1494) fixes a problem in xhci-hcd's resume routine. When the controller is runtime-resumed, this can only mean that one of the two root hubs has made a wakeup request and therefore needs to be resumed as well. Rather than try to determine which root hub requires attention (which might be difficult in the case where a new non-SuperSpeed device has been plugged in), the patch simply resumes both root hubs. Without this change, there is a race: The controller might be put back to sleep before it can activate its IRQ line, and the wakeup condition might never get handled. The patch also simplifies the logic in xhci_resume a little, combining some repeated flag settings into a single pair of statements. Signed-off-by: Alan Stern CC: Sarah Sharp Cc: stable Tested-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 747c5ead922b..aa94c0195791 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -799,7 +799,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) u32 command, temp = 0; struct usb_hcd *hcd = xhci_to_hcd(xhci); struct usb_hcd *secondary_hcd; - int retval; + int retval = 0; /* Wait a bit if either of the roothubs need to settle from the * transition into bus suspend. @@ -809,6 +809,9 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) xhci->bus_state[1].next_statechange)) msleep(100); + set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); + set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags); + spin_lock_irq(&xhci->lock); if (xhci->quirks & XHCI_RESET_ON_RESUME) hibernated = true; @@ -878,20 +881,13 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) return retval; xhci_dbg(xhci, "Start the primary HCD\n"); retval = xhci_run(hcd->primary_hcd); - if (retval) - goto failed_restart; - - xhci_dbg(xhci, "Start the secondary HCD\n"); - retval = xhci_run(secondary_hcd); if (!retval) { - set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); - set_bit(HCD_FLAG_HW_ACCESSIBLE, - &xhci->shared_hcd->flags); + xhci_dbg(xhci, "Start the secondary HCD\n"); + retval = xhci_run(secondary_hcd); } -failed_restart: hcd->state = HC_STATE_SUSPENDED; xhci->shared_hcd->state = HC_STATE_SUSPENDED; - return retval; + goto done; } /* step 4: set Run/Stop bit */ @@ -910,11 +906,14 @@ failed_restart: * Running endpoints by ringing their doorbells */ - set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); - set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags); - spin_unlock_irq(&xhci->lock); - return 0; + + done: + if (retval == 0) { + usb_hcd_resume_root_hub(hcd); + usb_hcd_resume_root_hub(xhci->shared_hcd); + } + return retval; } #endif /* CONFIG_PM */ -- 2.39.5