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    SubjectRe: [patch 19/26] USB: mutual exclusion for EHCI init and port resets
    Still needs the following update, IMO ... 

    ====== CUT HERE
    A recent patch added software synchronization during EHCI startup,
    so ports aren't switched away from the companion controllers after
    resets have started. This patch adds a short delay letting hardware
    get a chance to finish that port switching before any new resets begin.

    That is, both sides of that hardware race window need to be closed.

    Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
    ---
    drivers/usb/host/ehci-hcd.c | 5 ++++-
    1 file changed, 4 insertions(+), 1 deletion(-)

    --- g26.orig/drivers/usb/host/ehci-hcd.c 2007-11-13 16:07:12.000000000 -0800
    +++ g26/drivers/usb/host/ehci-hcd.c 2007-11-13 16:13:01.000000000 -0800
    @@ -594,12 +594,15 @@ static int ehci_run (struct usb_hcd *hcd
    * from the companions to the EHCI controller. If any of the
    * companions are in the middle of a port reset at the time, it
    * could cause trouble. Write-locking ehci_cf_port_reset_rwsem
    - * guarantees that no resets are in progress.
    + * guarantees that no resets are in progress. After we set CF,
    + * a short delay lets the hardware catch up; new resets shouldn't
    + * start before the port switching actions complete.
    */
    down_write(&ehci_cf_port_reset_rwsem);
    hcd->state = HC_STATE_RUNNING;
    ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
    ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */
    + msleep(5);
    up_write(&ehci_cf_port_reset_rwsem);

    temp = HC_VERSION(ehci_readl(ehci, &ehci->caps->hc_capbase));
    -
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