Hi Javier,
On Wed, Jun 26, 2024 at 11:56:16AM +0200, Javier Carrasco wrote:
> Use touch-overlay to support overlay objects such as buttons and a
> resized frame defined in the device tree.
>
> A key event will be generated if the coordinates of a touch event are
> within the area defined by the button properties.
>
> Reviewed-by: Jeff LaBundy <jeff@xxxxxxxxxxx>
> Signed-off-by: Javier Carrasco <javier.carrasco@xxxxxxxxxxxxxx>
> ---
> drivers/input/touchscreen/st1232.c | 48 +++++++++++++++++++++++++++-----------
> 1 file changed, 34 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c
> index 6475084aee1b..4fa31447dbc1 100644
> --- a/drivers/input/touchscreen/st1232.c
> +++ b/drivers/input/touchscreen/st1232.c
> @@ -22,6 +22,7 @@
> #include <linux/pm_qos.h>
> #include <linux/slab.h>
> #include <linux/types.h>
> +#include <linux/input/touch-overlay.h>
>
> #define ST1232_TS_NAME "st1232-ts"
> #define ST1633_TS_NAME "st1633-ts"
> @@ -57,6 +58,7 @@ struct st1232_ts_data {
> struct dev_pm_qos_request low_latency_req;
> struct gpio_desc *reset_gpio;
> const struct st_chip_info *chip_info;
> + struct list_head touch_overlay_list;
> int read_buf_len;
> u8 *read_buf;
> };
> @@ -138,14 +140,20 @@ static int st1232_ts_parse_and_report(struct st1232_ts_data *ts)
>
> for (i = 0; i < ts->chip_info->max_fingers; i++) {
> u8 *buf = &ts->read_buf[i * 4];
> + bool contact = buf[0] & BIT(7);
> + unsigned int x, y;
>
> - if (buf[0] & BIT(7)) {
> - unsigned int x = ((buf[0] & 0x70) << 4) | buf[1];
> - unsigned int y = ((buf[0] & 0x07) << 8) | buf[2];
> -
> - touchscreen_set_mt_pos(&pos[n_contacts],
> - &ts->prop, x, y);
> + if (contact) {
> + x = ((buf[0] & 0x70) << 4) | buf[1];
> + y = ((buf[0] & 0x07) << 8) | buf[2];
> + }
> + if (touch_overlay_process_event(&ts->touch_overlay_list, input,
> + contact ? &x : NULL,
> + contact ? &y : NULL, i))
> + continue;
So here is the exact issue I was talking about: you are using index of
the contact as a slot, which assumes that the device maintains position
of contacts in the overall event stream. However the driver uses input
core to track and assign slots (see calls to touchscreen_set_mt_pos()
and input_mt_assign_slots() below), which suggest that the touch
controller may reorder positions as needed.
Thanks.
--
Dmitry
