diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c index fdb3499660a3..e50a6fea9a60 100644 --- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -125,6 +125,10 @@ static void matrix_keypad_scan(struct work_struct *work) const unsigned short *keycodes = input_dev->keycode; uint32_t new_state[MATRIX_MAX_COLS]; int row, col, code; + u32 init_row_state, new_row_state; + + /* read initial row state to detect changes between scan */ + init_row_state = read_row_state(keypad); /* de-activate all columns for scanning */ activate_all_cols(keypad, false); @@ -173,6 +177,18 @@ static void matrix_keypad_scan(struct work_struct *work) keypad->scan_pending = false; enable_row_irqs(keypad); } + + /* read new row state and detect if value has changed */ + new_row_state = read_row_state(keypad); + if (init_row_state != new_row_state) { + guard(spinlock_irq)(&keypad->lock); + if (unlikely(keypad->scan_pending || keypad->stopped)) + return; + disable_row_irqs(keypad); + keypad->scan_pending = true; + schedule_delayed_work(&keypad->work, + msecs_to_jiffies(keypad->debounce_ms)); + } } static irqreturn_t matrix_keypad_interrupt(int irq, void *id)