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    Subject[021/244] USB: EHCI: Do not rely on PORT_SUSPEND to stop USB resuming in ehci_bus_resume().
    3.0-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Wang Zhi <zhi.wang@windriver.com>

    commit d0f2fb2500b1c5fe4967eb45d8c9bc758d7aef80 upstream.

    >From EHCI Spec p.28 HC should clear PORT_SUSPEND when SW clears
    PORT_RESUME. In Intel Oaktrail platform, MPH (Multi-Port Host
    Controller) core clears PORT_SUSPEND directly when SW sets PORT_RESUME
    bit. If we rely on PORT_SUSPEND bit to stop USB resume, we will miss
    the action of clearing PORT_RESUME. This will cause unexpected long
    resume signal on USB bus.

    Signed-off-by: Wang Zhi <zhi.wang@windriver.com>
    Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    drivers/usb/host/ehci-hub.c | 7 +++----
    1 file changed, 3 insertions(+), 4 deletions(-)

    --- a/drivers/usb/host/ehci-hub.c
    +++ b/drivers/usb/host/ehci-hub.c
    @@ -343,7 +343,7 @@ static int ehci_bus_resume (struct usb_h
    u32 temp;
    u32 power_okay;
    int i;
    - u8 resume_needed = 0;
    + unsigned long resume_needed = 0;

    if (time_before (jiffies, ehci->next_statechange))
    msleep(5);
    @@ -416,7 +416,7 @@ static int ehci_bus_resume (struct usb_h
    if (test_bit(i, &ehci->bus_suspended) &&
    (temp & PORT_SUSPEND)) {
    temp |= PORT_RESUME;
    - resume_needed = 1;
    + set_bit(i, &resume_needed);
    }
    ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
    }
    @@ -431,8 +431,7 @@ static int ehci_bus_resume (struct usb_h
    i = HCS_N_PORTS (ehci->hcs_params);
    while (i--) {
    temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
    - if (test_bit(i, &ehci->bus_suspended) &&
    - (temp & PORT_SUSPEND)) {
    + if (test_bit(i, &resume_needed)) {
    temp &= ~(PORT_RWC_BITS | PORT_RESUME);
    ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
    ehci_vdbg (ehci, "resumed port %d\n", i + 1);



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