diff options
Diffstat (limited to 'main/touch.c')
| -rw-r--r-- | main/touch.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/main/touch.c b/main/touch.c new file mode 100644 index 0000000..f13183d --- /dev/null +++ b/main/touch.c @@ -0,0 +1,123 @@ +#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; +} |