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    SubjectRe: [PATCH v1] Input: tegra-kbc - enable key interrupt for wakeup
    Hi Rakesh,

    On Thu, Jan 19, 2012 at 11:51 PM, Rakesh Iyer <> wrote:
    >>       if (device_may_wakeup(&pdev->dev)) {
    >>               disable_irq_wake(kbc->irq);
    >>               tegra_kbc_setup_wakekeys(kbc, false);
    >> +             /* We will use fifo interrupts for key detection. */
    >> +             tegra_kbc_set_keypress_interrupt(kbc, false);
    > Why do yo disable on resume why not have it enabled always?
    >>               /* Restore the resident time of continuous polling mode. */
    >>               writel(kbc->cp_to_wkup_dly, kbc->mmio + KBC_TO_CNT_0);
    > For the relevant discussion, Tegra KBC provides the following interrupts -
    > a) The keypress interrupt which is generated as soon as a key is pressed,
    >      before matrix scanning begins.
    > b) FIFO interrupt which is generated when actual keys are decoded from the matrix,
    >     and put into the FIFO.
    > During normal operation the keypress interrupt is not useful as we have to wait for the
    > keys to make it into the FIFO before reporting it to the higher layers.
    > Since we have turned off scanning(in the following commit) we cannot use the FIFO interrupt
    > during the resume, so we rely on the keypress interrupt and generate the wakeup key.
    > Commit that turned off scanning
    >    Input: tegra-kbc - fix wakeup from suspend
    >    For wakeup to be reliable, kbc needs to be in interrupt mode before suspend.

    Does it need to be disabled at resume?

    >    Created common routine to control the FIFO interrupt.
    >    Added synchronization to ensure orderly suspend.
    > Regards
    > Rakesh
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