On Sun, Feb 04, 2018 at 08:19:22AM +0800, Zhang Bo wrote:
> If matrix_keypad_stop() is calling and the keypad interrupt is triggered,
> disable_row_irqs() is called by both matrix_keypad_interrupt() and
> matrix_keypad_stop() at the same time. then disable_row_irqs() is called
> twice, and the device enter suspend state before keypad->work is executed.
> At this condition the device will start keypad and enable irq once after
> resume. and then irqs are disabled yet because irqs are disabled twice and
> only enable once.
>
> Take lock around keypad->stopped to ensure irqs operation is in atomic
> operation.
>
> Signed-off-by: Zhang Bo <zbs...@126.com>
Applied, thank you.
> ---
> Changes in v3:
> - delete no needed lock protection, only add lock in matrix_keypad_stop().
> Changes in v2:
> - Change commit message and full name in the signed-off-by tag.
>
> drivers/input/keyboard/matrix_keypad.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/input/keyboard/matrix_keypad.c
> b/drivers/input/keyboard/matrix_keypad.c
> index 1f316d66e6f7..41614c185918 100644
> --- a/drivers/input/keyboard/matrix_keypad.c
> +++ b/drivers/input/keyboard/matrix_keypad.c
> @@ -218,8 +218,10 @@ static void matrix_keypad_stop(struct input_dev *dev)
> {
> struct matrix_keypad *keypad = input_get_drvdata(dev);
>
> + spin_lock_irq(&keypad->lock);
> keypad->stopped = true;
> - mb();
> + spin_unlock_irq(&keypad->lock);
> +
> flush_work(&keypad->work.work);
> /*
> * matrix_keypad_scan() will leave IRQs enabled;
> --
> 2.14.3
>
>
--
Dmitry
