Merge develop into main (#303)

- `DisplayDevice` improvements related `DisplayDriver`
- Replaced incorrect usage of `spiBusHandle` with `spiHostDevice` in all SPI display devices
- Disabled `DisplayDriver` support for RGB displays for now
- Updated `GraphicsDemo` project for the above changes
- TactilityC improvements:
  - created `tt_hal_device_find()`
  - created `tt_hal_display_*`
  - created `tt_hal_touch_*`
  - created `tt_lvgl_*`
  - export `tt_app_*` calls

ExternalApps/GraphicsDemo/main/Source/Application.cpp

@@ -0,0 +1,72 @@
+#include "Application.h"
+#include "PixelBuffer.h"
+#include "esp_log.h"
+
+#include <tt_kernel.h>
+
+constexpr auto TAG = "Application";
+
+static bool isTouched(TouchDriver* touch) {
+    uint16_t x, y, strength;
+    uint8_t pointCount = 0;
+    return touch->getTouchedPoints(&x, &y, &strength, &pointCount, 1);
+}
+
+void createRgbRow(PixelBuffer& buffer) {
+    uint8_t offset = buffer.getPixelWidth() / 3;
+    for (int i = 0; i < buffer.getPixelWidth(); ++i) {
+        if (i < offset) {
+            buffer.setPixel(i, 0, 255, 0, 0);
+        } else if (i < offset * 2) {
+            buffer.setPixel(i, 0, 0, 255, 0);
+        } else {
+            buffer.setPixel(i, 0, 0, 0, 255);
+        }
+    }
+}
+
+void createRgbFadingRow(PixelBuffer& buffer) {
+    uint8_t stroke = buffer.getPixelWidth() / 3;
+    for (int i = 0; i < buffer.getPixelWidth(); ++i) {
+        if (i < stroke) {
+            auto color = i * 255 / stroke;
+            buffer.setPixel(i, 0, color, 0, 0);
+        } else if (i < stroke * 2) {
+            auto color = (i - stroke) * 255 / stroke;
+            buffer.setPixel(i, 0, 0, color, 0);
+        } else {
+            auto color = (i - (2*stroke)) * 255 / stroke;
+            buffer.setPixel(i, 0, 0, 0, color);
+        }
+    }
+}
+
+void runApplication(DisplayDriver* display, TouchDriver* touch) {
+    // Single row buffers
+    PixelBuffer line_clear_buffer(display->getWidth(), 1, display->getColorFormat());
+    line_clear_buffer.clear();
+    PixelBuffer line_buffer(display->getWidth(), 1, display->getColorFormat());
+    line_buffer.clear();
+
+    do {
+        // Draw row by row
+        // This is placed in a loop to test the SPI locking mechanismss
+        for (int i = 0; i < display->getHeight(); i++) {
+
+            if (i == 0) {
+                createRgbRow(line_buffer);
+            } else if (i == display->getHeight() / 2) {
+                createRgbFadingRow(line_buffer);
+            }
+
+            display->lock();
+            display->drawBitmap(0, i, display->getWidth(), i + 1, line_buffer.getData());
+            display->unlock();
+        }
+
+        // Give other tasks space to breathe
+        // SPI displays would otherwise time out SPI SD card access
+        tt_kernel_delay_ticks(1);
+    } while (!isTouched(touch));
+}
+

ExternalApps/GraphicsDemo/main/Source/Main.cpp

@@ -0,0 +1,71 @@
+#include "Application.h"
+#include "drivers/DisplayDriver.h"
+#include "drivers/TouchDriver.h"
+
+#include <esp_log.h>
+
+#include <tt_app.h>
+#include <tt_lvgl.h>
+
+constexpr auto TAG = "Main";
+
+static void onCreate(AppHandle appHandle, void* data) {
+    uint16_t display_count = 0;
+    DeviceId display_id;
+    if (!tt_hal_device_find(DEVICE_TYPE_DISPLAY, &display_id, &display_count, 1)) {
+        ESP_LOGI(TAG, "No display device found");
+        return;
+    }
+
+    uint16_t touch_count = 0;
+    DeviceId touch_id;
+    if (!tt_hal_device_find(DEVICE_TYPE_TOUCH, &touch_id, &touch_count, 1)) {
+        ESP_LOGI(TAG, "No touch device found");
+        return;
+    }
+
+    // Stop LVGL first (because it's currently using the drivers we want to use)
+    tt_lvgl_stop();
+
+    ESP_LOGI(TAG, "Creating display driver");
+    auto display = new DisplayDriver(display_id);
+
+    ESP_LOGI(TAG, "Creating touch driver");
+    auto touch = new TouchDriver(touch_id);
+
+    // Run the main logic
+    ESP_LOGI(TAG, "Running application");
+    runApplication(display, touch);
+
+    ESP_LOGI(TAG, "Cleanup display driver");
+    delete display;
+
+    ESP_LOGI(TAG, "Cleanup touch driver");
+    delete touch;
+
+    ESP_LOGI(TAG, "Stopping application");
+    tt_app_stop();
+}
+
+static void onDestroy(AppHandle appHandle, void* data) {
+    // Restart LVGL to resume rendering of regular apps
+    if (!tt_lvgl_is_started()) {
+        ESP_LOGI(TAG, "Restarting LVGL");
+        tt_lvgl_start();
+    }
+}
+
+ExternalAppManifest manifest = {
+    .name = "Hello World",
+    .onCreate = onCreate,
+    .onDestroy = onDestroy
+};
+
+extern "C" {
+
+int main(int argc, char* argv[]) {
+    tt_app_register(&manifest);
+    return 0;
+}
+
+}