| Message ID | 20180204001922.32084-1-zbsdta@126.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
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 <zbsdta@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 > >
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;
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 <zbsdta@126.com> --- 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(-)