diff options
Diffstat (limited to 'drivers/input/keyboard/matrix_keypad.c')
| -rw-r--r-- | drivers/input/keyboard/matrix_keypad.c | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c index e46473cb817c..e50a6fea9a60 100644 --- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -104,6 +104,16 @@ static void disable_row_irqs(struct matrix_keypad *keypad) disable_irq_nosync(keypad->row_irqs[i]); } +static uint32_t read_row_state(struct matrix_keypad *keypad) +{ + int row; + u32 row_state = 0; + + for (row = 0; row < keypad->num_row_gpios; row++) + row_state |= row_asserted(keypad, row) ? BIT(row) : 0; + return row_state; +} + /* * This gets the keys from keyboard and reports it to input subsystem */ @@ -115,6 +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); @@ -129,9 +143,7 @@ static void matrix_keypad_scan(struct work_struct *work) activate_col(keypad, col, true); - for (row = 0; row < keypad->num_row_gpios; row++) - new_state[col] |= - row_asserted(keypad, row) ? BIT(row) : 0; + new_state[col] = read_row_state(keypad); activate_col(keypad, col, false); } @@ -165,6 +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) |