diff options
| -rw-r--r-- | drivers/usb/host/ehci-timer.c | 53 |
1 files changed, 25 insertions, 28 deletions
diff --git a/drivers/usb/host/ehci-timer.c b/drivers/usb/host/ehci-timer.c index cc9ad5892d19..97815d0fc97c 100644 --- a/drivers/usb/host/ehci-timer.c +++ b/drivers/usb/host/ehci-timer.c @@ -295,8 +295,7 @@ static void end_free_itds(struct ehci_hcd *ehci) /* Handle lost (or very late) IAA interrupts */ static void ehci_iaa_watchdog(struct ehci_hcd *ehci) { - if (ehci->rh_state != EHCI_RH_RUNNING) - return; + u32 cmd, status; /* * Lost IAA irqs wedge things badly; seen first with a vt8235. @@ -304,34 +303,32 @@ static void ehci_iaa_watchdog(struct ehci_hcd *ehci) * (a) SMP races against real IAA firing and retriggering, and * (b) clean HC shutdown, when IAA watchdog was pending. */ - if (ehci->async_iaa) { - u32 cmd, status; - - /* If we get here, IAA is *REALLY* late. It's barely - * conceivable that the system is so busy that CMD_IAAD - * is still legitimately set, so let's be sure it's - * clear before we read STS_IAA. (The HC should clear - * CMD_IAAD when it sets STS_IAA.) - */ - cmd = ehci_readl(ehci, &ehci->regs->command); - - /* - * If IAA is set here it either legitimately triggered - * after the watchdog timer expired (_way_ late, so we'll - * still count it as lost) ... or a silicon erratum: - * - VIA seems to set IAA without triggering the IRQ; - * - IAAD potentially cleared without setting IAA. - */ - status = ehci_readl(ehci, &ehci->regs->status); - if ((status & STS_IAA) || !(cmd & CMD_IAAD)) { - COUNT(ehci->stats.lost_iaa); - ehci_writel(ehci, STS_IAA, &ehci->regs->status); - } + if (!ehci->async_iaa || ehci->rh_state != EHCI_RH_RUNNING) + return; + + /* If we get here, IAA is *REALLY* late. It's barely + * conceivable that the system is so busy that CMD_IAAD + * is still legitimately set, so let's be sure it's + * clear before we read STS_IAA. (The HC should clear + * CMD_IAAD when it sets STS_IAA.) + */ + cmd = ehci_readl(ehci, &ehci->regs->command); - ehci_vdbg(ehci, "IAA watchdog: status %x cmd %x\n", - status, cmd); - end_unlink_async(ehci); + /* + * If IAA is set here it either legitimately triggered + * after the watchdog timer expired (_way_ late, so we'll + * still count it as lost) ... or a silicon erratum: + * - VIA seems to set IAA without triggering the IRQ; + * - IAAD potentially cleared without setting IAA. + */ + status = ehci_readl(ehci, &ehci->regs->status); + if ((status & STS_IAA) || !(cmd & CMD_IAAD)) { + COUNT(ehci->stats.lost_iaa); + ehci_writel(ehci, STS_IAA, &ehci->regs->status); } + + ehci_dbg(ehci, "IAA watchdog: status %x cmd %x\n", status, cmd); + end_unlink_async(ehci); } |