UEFI Display/Inputs driver
Overview
The UEFI display/input driver offers support for using LVGL with UEFI.
Prerequisites
You need the following protocols available:
EFI_LOADED_IMAGE_PROTOCOL_GUID, for file system support (used to determine the file system that was used to load the application)
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID, for file system support
EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL_GUID, for keyboard support
EFI_SIMPLE_POINTER_PROTOCOL_GUID, for mouse support
EFI_ABSOLUTE_POINTER_PROTOCOL_GUID, for touch support
EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID, for drawing
EFI_EDID_ACTIVE_PROTOCOL_GUID, for drawing (optional)
Configure UEFI driver
Enable the UEFI driver support in lv_conf.h
#define LV_USE_UEFI 1
Enable the the memory core functions, which are wrappers around AllocatePool and FreePool (using memory of type EfiBootServicesData) if you do not wan't to use your own implementations
#define LV_UEFI_USE_MEMORY_SERVICES 1
You can enable file system support for the file system from which the appliation got loaded (default letter 'E')
#define LV_USE_FS_UEFI 1
You need to define an include file which contains the basic UEFI definitions (protocols and types), there are 2 predefined files which can be used for EDK2 and gnu-efi
#define LV_USE_UEFI_INCLUDE <lvgl/src/drivers/uefi/lv_uefi_edk2.h>
// or
#define LV_USE_UEFI_INCLUDE <lvgl/src/drivers/uefi/lv_uefi_gnu_efi.h>
Usage
#include "lvgl/lvgl.h"
#include "lvgl/examples/lv_examples.h"
#include "lvgl/demos/lv_demos.h"
EFI_STATUS EFIAPI EfiMain(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE * SystemTable)
{
lv_uefi_init(ImageHandle, SystemTable);
lv_init();
if(!lv_is_initialized()) return EFI_NOT_READY;
EFI_HANDLE handle = NULL;
lv_display_t* display = NULL;
lv_indev_t* indev = NULL;
lv_group_t* group = NULL;
lv_obj_t* cursor = NULL;
// used to get out of the main loop
size_t counter;
// Init the display
handle = lv_uefi_display_get_active();
if(handle == NULL) {
handle = lv_uefi_display_get_any();
}
if(handle == NULL) {
lv_deinit();
return EFI_UNSUPPORTED;
}
display = lv_uefi_display_create(handle);
lv_display_set_default(display);
// Create the group
group = lv_group_create();
lv_group_set_default(group);
// Create an image that can be used as cursor
cursor = lv_image_create(lv_layer_top());
lv_image_set_src(cursor, "E:cursor.png");
// Create the input devices
indev = lv_uefi_simple_text_input_indev_create();
lv_indev_set_group(indev, lv_group_get_default());
lv_uefi_simple_text_input_indev_add_all(indev);
indev = lv_uefi_simple_pointer_indev_create(NULL);
lv_uefi_simple_pointer_indev_add_all(indev);
lv_indev_set_cursor(indev, cursor);
indev = lv_uefi_absolute_pointer_indev_create(NULL);
lv_uefi_absolute_pointer_indev_add_all(indev);
lv_demo_widgets();
// Run main loop for ~ 10 seconds
counter = 0;
while(counter < 10000) {
counter ++;
gBS->Stall(1000);
lv_tick_inc(1);
lv_timer_handler();
}
return EFI_SUCCESS;
}