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

TactilityC/Include/tt_hal_display.h

@@ -0,0 +1,91 @@
+#pragma once
+
+#include <tt_kernel.h>
+
+#include "tt_hal_device.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void* DisplayDriverHandle;
+
+enum ColorFormat {
+    COLOR_FORMAT_MONOCHROME, // 1 bpp
+    COLOR_FORMAT_BGR565,
+    COLOR_FORMAT_BGR565_SWAPPED,
+    COLOR_FORMAT_RGB565,
+    COLOR_FORMAT_RGB565_SWAPPED,
+    COLOR_FORMAT_RGB888
+};
+
+/**
+ * Check if the display driver interface is supported for this device.
+ * @param[in] displayId the identifier of the display device
+ * @return true if the driver is supported.
+ */
+bool tt_hal_display_driver_supported(DeviceId displayId);
+
+/**
+ * Allocate a driver object for the specified displayId.
+ * @warning check whether the driver is supported by calling tt_hal_display_driver_supported() first
+ * @param[in] displayId the identifier of the display device
+ * @return the driver handle
+ */
+DisplayDriverHandle tt_hal_display_driver_alloc(DeviceId displayId);
+
+/**
+ * Free the memory for the display driver.
+ * @param[in] handle the display driver handle
+ */
+void tt_hal_display_driver_free(DisplayDriverHandle handle);
+
+/**
+ * Lock the display device. Call this function before doing any draw calls.
+ * Certain display devices are on a shared bus (e.g. SPI) so they must run
+ * mutually exclusive with other devices on the same bus (e.g. SD card)
+ * @param[in] handle the display driver handle
+ * @param[in] timeout the maximum amount of ticks to wait for getting a lock
+ * @return true if the lock was acquired
+ */
+bool tt_hal_display_driver_lock(DisplayDriverHandle handle, TickType timeout);
+
+/**
+ * Unlock the display device. Must be called exactly once after locking.
+ * @param[in] handle the display driver handle
+ */
+void tt_hal_display_driver_unlock(DisplayDriverHandle handle);
+
+/**
+ * @param[in] handle the display driver handle
+ * @return the native color format for this display
+ */
+ColorFormat tt_hal_display_driver_get_colorformat(DisplayDriverHandle handle);
+
+/**
+ * @param[in] handle the display driver handle
+ * @return the horizontal resolution of the display
+ */
+uint16_t tt_hal_display_driver_get_pixel_width(DisplayDriverHandle handle);
+
+/**
+ * @param[in] handle the display driver handle
+ * @return the vertical resolution of the display
+ */
+uint16_t tt_hal_display_driver_get_pixel_height(DisplayDriverHandle handle);
+
+/**
+ * Draw pixels on the screen. Make sure to call the lock function first and unlock afterwards.
+ * Many draw calls can be done inbetween a single lock and unlock.
+ * @param[in] handle the display driver handle
+ * @param[in] xStart the starting x coordinate for rendering the pixel data
+ * @param[in] yStart the starting y coordinate for rendering the pixel data
+ * @param[in] xEnd the last x coordinate for rendering the pixel data (absolute pixel value, not relative to xStart!)
+ * @param[in] yEnd the last y coordinate for rendering the pixel data (absolute pixel value, not relative to yStart!)
+ * @param[in] pixelData a buffer of pixels. the data is placed as "RowRowRowRow". The size depends on the ColorFormat
+ */
+void tt_hal_display_driver_draw_bitmap(DisplayDriverHandle handle, int xStart, int yStart, int xEnd, int yEnd, const void* pixelData);
+
+#ifdef __cplusplus
+}
+#endif