LilyGo T-Deck keyboard support & display driver improvements (#19)

* LilyGo T-Deck keyboard support * reverse logic * docs and readability * cleanup * optimize driver buffer * cleanup
2024-01-27 12:34:02 +01:00
parent 14eb43211d
commit ccbe6b7ab8
21 changed files with 302 additions and 73 deletions
@@ -0,0 +1,95 @@
+#include "keyboard.h"
+#include "config.h"
+#include "hal/lv_hal.h"
+#include "tactility_core.h"
+#include "ui/lvgl_keypad.h"
+#include <driver/i2c.h>
+
+#define TAG "tdeck_keyboard"
+#define KEYBOARD_SLAVE_ADDRESS 0x55
+
+typedef struct {
+    lv_indev_drv_t* driver;
+    lv_indev_t* device;
+} KeyboardData;
+
+static inline esp_err_t keyboard_i2c_read(uint8_t* output) {
+    return i2c_master_read_from_device(
+        TDECK_I2C_BUS_HANDLE,
+        KEYBOARD_SLAVE_ADDRESS,
+        output,
+        1,
+        configTICK_RATE_HZ / 10
+    );
+}
+
+void keyboard_wait_for_response() {
+    TT_LOG_I(TAG, "wake await...");
+    bool awake = false;
+    uint8_t read_buffer = 0x00;
+    do {
+        awake = keyboard_i2c_read(&read_buffer) == ESP_OK;
+        if (!awake) {
+            tt_delay_ms(100);
+        }
+    } while (!awake);
+    TT_LOG_I(TAG, "awake");
+}
+
+/**
+ * The callback simulates press and release events, because the T-Deck
+ * keyboard only publishes press events on I2C.
+ * LVGL currently works without those extra release events, but they
+ * are implemented for correctness and future compatibility.
+ *
+ * @param indev_drv
+ * @param data
+ */
+static void keyboard_read_callback(TT_UNUSED struct _lv_indev_drv_t* indev_drv, lv_indev_data_t* data) {
+    static uint8_t last_buffer = 0x00;
+    uint8_t read_buffer = 0x00;
+
+    // Defaults
+    data->key = 0;
+    data->state = LV_INDEV_STATE_RELEASED;
+
+    if (keyboard_i2c_read(&read_buffer) == ESP_OK) {
+        if (read_buffer == 0 && read_buffer != last_buffer) {
+            TT_LOG_I(TAG, "released %d", last_buffer);
+            data->key = last_buffer;
+            data->state = LV_INDEV_STATE_RELEASED;
+        } else if (read_buffer != 0) {
+            TT_LOG_I(TAG, "pressed %d", read_buffer);
+            data->key = read_buffer;
+            data->state = LV_INDEV_STATE_PRESSED;
+        }
+    }
+
+    last_buffer = read_buffer;
+}
+
+Keyboard keyboard_alloc(_Nullable lv_disp_t* display) {
+    KeyboardData* data = malloc(sizeof(KeyboardData));
+
+    data->driver = malloc(sizeof(lv_indev_drv_t));
+    memset(data->driver, 0, sizeof(lv_indev_drv_t));
+    lv_indev_drv_init(data->driver);
+
+    data->driver->type = LV_INDEV_TYPE_KEYPAD;
+    data->driver->read_cb = &keyboard_read_callback;
+    data->driver->disp = display;
+
+    data->device = lv_indev_drv_register(data->driver);
+    tt_check(data->device != NULL);
+
+    tt_lvgl_keypad_set_indev(data->device);
+
+    return data;
+}
+
+void keyboard_free(Keyboard keyboard) {
+    KeyboardData* data = (KeyboardData*)keyboard;
+    lv_indev_delete(data->device);
+    free(data->driver);
+    free(data);
+}