4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zhang Bo zbsdta@126.com
commit ea4f7bd2aca9f68470e9aac0fc9432fd180b1fe7 upstream.
If matrix_keypad_stop() is executing and the keypad interrupt is triggered, disable_row_irqs() may be called by both matrix_keypad_interrupt() and matrix_keypad_stop() at the same time, causing interrupts to be disabled twice and the keypad being "stuck" after resuming.
Take lock when setting keypad->stopped to ensure that ISR will not race with matrix_keypad_stop() disabling interrupts.
Signed-off-by: Zhang Bo zbsdta@126.com Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/input/keyboard/matrix_keypad.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -216,8 +216,10 @@ static void matrix_keypad_stop(struct in { 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;