On Fri, Feb 28, 2020 at 10:02:43AM -0800, Tony Lindgren wrote:
> In addition to handling errata i689 for idle with state, we must also
> check for lost key up interrupts on fast key presses.
>
> For example rapidly pressing shift-shift-j can sometimes produce a J
> instead of j. Let's fix the issue by scanning the keyboard in two
> phases. First we scan for any key up events that we may have missed,
> and then we scan for key down events.
>
> Cc: Arthur Demchenkov <spinal.by@xxxxxxxxx>
> Cc: Merlijn Wajer <merlijn@xxxxxxxxxx>
> Cc: Pavel Machek <pavel@xxxxxx>
> Cc: Sebastian Reichel <sre@xxxxxxxxxx>
> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
> ---
> drivers/input/keyboard/omap4-keypad.c | 48 ++++++++++++++++++---------
> 1 file changed, 32 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/input/keyboard/omap4-keypad.c b/drivers/input/keyboard/omap4-keypad.c
> --- a/drivers/input/keyboard/omap4-keypad.c
> +++ b/drivers/input/keyboard/omap4-keypad.c
> @@ -109,6 +109,34 @@ static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
> keypad_data->base + keypad_data->irqreg_offset + offset);
> }
>
> +static void omap4_keypad_scan_state(struct omap4_keypad *keypad_data,
> + unsigned char *key_state,
> + bool down)
> +{
> + struct input_dev *input_dev = keypad_data->input;
> + unsigned int col, row, code, changed;
> + bool key_down;
> +
> + for (row = 0; row < keypad_data->rows; row++) {
> + changed = key_state[row] ^ keypad_data->key_state[row];
> + if (!changed)
> + continue;
> +
> + for (col = 0; col < keypad_data->cols; col++) {
> + if (changed & (1 << col)) {
Looking at all too this, key state is 64 bit value, so if we make it a
bitmap and use "for_each_set_bit()" we can simplify this scanning code.
Thanks.
--
Dmitry
