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#include "touch.h"
#include <stdint.h>
#include "driver/i2c_master.h"
#include "esp_check.h"
#include "esp_log.h"
#include "esp_timer.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "display.h"
#include "state_machine.h"
#include "viewport_state.h"
static const char *TAG = "touch";
#define FT5426_ADDR 0x38
#define FT5426_I2C_FREQ_HZ 400000
// FT5x06/FT5426 register map (subset).
#define FT_REG_DEV_MODE 0x00
#define FT_REG_GEST_ID 0x01
#define FT_REG_TD_STATUS 0x02 // low 4 bits = touch count
#define FT_REG_P1_XH 0x03 // X high (bits 0..3) + event flag (bits 6..7)
#define FT_REG_P1_XL 0x04
#define FT_REG_P1_YH 0x05
#define FT_REG_P1_YL 0x06
#define POLL_PERIOD_MS 30
#define TAP_MAX_MS 500
#define TAP_MAX_MOVE_PX 25
#define TAP_DEBOUNCE_MS 150
static i2c_master_dev_handle_t s_dev;
static TaskHandle_t s_task;
static esp_err_t ft_read(uint8_t reg, uint8_t *buf, size_t n)
{
return i2c_master_transmit_receive(s_dev, ®, 1, buf, n, 50);
}
static void touch_task(void *arg)
{
bool was_down = false;
uint64_t down_us = 0;
uint16_t down_x = 0;
uint16_t down_y = 0;
uint64_t last_tap_us = 0;
uint8_t buf[7];
for (;;) {
vTaskDelay(pdMS_TO_TICKS(POLL_PERIOD_MS));
if (ft_read(FT_REG_DEV_MODE, buf, sizeof(buf)) != ESP_OK) continue;
uint8_t touches = buf[FT_REG_TD_STATUS] & 0x0F;
if (touches > 0) {
// Always capture P1; we only care about taps, not multi-touch.
uint16_t x = ((buf[FT_REG_P1_XH] & 0x0F) << 8) | buf[FT_REG_P1_XL];
uint16_t y = ((buf[FT_REG_P1_YH] & 0x0F) << 8) | buf[FT_REG_P1_YL];
if (!was_down) {
was_down = true;
down_us = (uint64_t)esp_timer_get_time();
down_x = x;
down_y = y;
}
} else if (was_down) {
// Release: was-down → up.
was_down = false;
uint64_t now = (uint64_t)esp_timer_get_time();
if (now - last_tap_us < (uint64_t)TAP_DEBOUNCE_MS * 1000ULL) continue;
uint64_t dt_ms = (now - down_us) / 1000ULL;
// No reliable last position from the burst; use down coordinates
// for the duration check, ignore movement check beyond the down
// capture. Good enough for tap-vs-press.
(void)down_x; (void)down_y; (void)TAP_MAX_MOVE_PX;
if (dt_ms > 0 && dt_ms <= TAP_MAX_MS) {
last_tap_us = now;
viewport_run_state_t cur = state_machine_current();
viewport_run_state_t target =
(cur == VIEWPORT_STATE_AWAKE) ? VIEWPORT_STATE_ASLEEP
: VIEWPORT_STATE_AWAKE;
ESP_LOGI(TAG, "tap (%lu ms) -> %s", (unsigned long)dt_ms,
target == VIEWPORT_STATE_AWAKE ? "wake" : "sleep");
state_machine_set_local(target);
}
}
}
}
esp_err_t touch_init(void)
{
i2c_master_bus_handle_t bus = display_i2c_bus();
if (!bus) {
ESP_LOGW(TAG, "I2C bus unavailable — display didn't come up; skipping touch");
return ESP_ERR_INVALID_STATE;
}
i2c_device_config_t cfg = {
.dev_addr_length = I2C_ADDR_BIT_LEN_7,
.device_address = FT5426_ADDR,
.scl_speed_hz = FT5426_I2C_FREQ_HZ,
};
ESP_RETURN_ON_ERROR(i2c_master_bus_add_device(bus, &cfg, &s_dev),
TAG, "i2c add FT5426");
// Sanity poll: read device mode.
uint8_t dev_mode = 0;
esp_err_t err = ft_read(FT_REG_DEV_MODE, &dev_mode, 1);
if (err != ESP_OK) {
ESP_LOGE(TAG, "FT5426 @0x38 unreachable (%s) — check INT jumper",
esp_err_to_name(err));
return err;
}
ESP_LOGI(TAG, "FT5426 ack'd (dev_mode=0x%02x)", dev_mode);
BaseType_t ok = xTaskCreate(touch_task, "touch", 3072, NULL, 4, &s_task);
return (ok == pdPASS) ? ESP_OK : ESP_FAIL;
}
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