4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zhang Bo <zbsdta@xxxxxxx>
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@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;