feat(esp_lcd): updated lvgl example to loading image from file system

which can help to reduce the firmware bin size

examples/peripherals/lcd/i80_controller/README.md

@@ -1,5 +1,6 @@
 | Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 |
 | ----------------- | ----- | -------- | -------- |
+
 # LVGL porting example (based on i80 interfaced LCD controller)
 
 LVGL is an open-source graphics library for creating modern GUIs. It has plenty of built-in graphical elements with low memory footprint, which is friendly for embedded GUI applications.
@@ -26,7 +27,7 @@ This example uses the [esp_timer](https://docs.espressif.com/projects/esp-idf/en
 
 The connection between ESP Board and the LCD is as follows:
 
-```
+```text
    ESP Board                      LCD Screen
 ┌─────────────┐              ┌────────────────┐
 │             │              │                │
@@ -71,6 +72,8 @@ Run `idf.py menuconfig` to open a terminal UI where you can tune specific config
 
 * `Allocate color data from PSRAM`: Select this option if you want to allocate the LVGL draw buffers from PSRAM.
 
+* `LCD image source from`: Select where to load the image resource. See [Image Resource](#image-resource) for more details.
+
 Run `idf.py -p PORT build flash monitor` to build, flash and monitor the project. A fancy animation will show up on the LCD as expected.
 
 The first time you run `idf.py` for the example will cost extra time as the build system needs to address the component dependencies and downloads the missing components from registry into `managed_components` folder.
@@ -99,10 +102,17 @@ I (558) example: Display LVGL animation
 This example supports touch screen connected via I2C. You can enable it by running `idf.py menuconfig` and navigating to `Example Configuration -> Enable LCD touch`. When touch is enabled, there will be a new button in the GUI that can restart the animation.
 
 These touch controllers are supported:
+
 * [GT911](https://github.com/espressif/esp-bsp/tree/master/components/lcd_touch/esp_lcd_touch_gt911)
 * [TT21100](https://github.com/espressif/esp-bsp/tree/master/components/lcd_touch/esp_lcd_touch_tt21100)
 * [FT5X06](https://github.com/espressif/esp-bsp/tree/master/components/lcd_touch/esp_lcd_touch_ft5x06)
 
+## Image Resource
+
+This example supports two ways of reading images
+
+* from the [SPIFFS file system](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/storage/spiffs.html). This is the suggested way we use in the example. It may take a little bit longer to load the image because of the bottleneck of the SPI flash read speed, but it will save the binary size.
+* from the embedded binary (i.e., pre-decode the image into an array and pack it together with the application firmware). By this way, you can get faster image loading speed at the cost of bloating your application binary. What's worse, if you enabled the [XIP from PSRAM](https://github.com/espressif/esp-idf/tree/master/examples/system/xip_from_psram) feature, it will increase the PSRAM usage as well.
 
 ## Troubleshooting
 
@@ -110,4 +120,4 @@ These touch controllers are supported:
 
    This is because of the limited PSRAM bandwidth, compared to the internal SRAM. You can either decrease the PCLK clock `EXAMPLE_LCD_PIXEL_CLOCK_HZ` in [i80_controller_example_main.c](main/i80_controller_example_main.c) or increase the PSRAM working frequency `SPIRAM_SPEED` from the KConfig (e.g. **ESP32S3-Specific** -> **Set RAM clock speed**) or decrease the FPS in LVGL configuration. For illustration, this example has set the refresh period to 100ms in the default sdkconfig file.
 
-For any technical queries, please open an [issue] (https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.
+For any technical queries, please open an [issue](https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.

examples/peripherals/lcd/i80_controller/main/CMakeLists.txt

@@ -1,4 +1,12 @@
-file(GLOB_RECURSE IMAGE_SOURCES images/*.c)
+set(embedded_images)
+if(CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY)
+    file(GLOB_RECURSE embedded_images images/*.c)
+endif()
 
-idf_component_register(SRCS "i80_controller_example_main.c" "lvgl_demo_ui.c" ${IMAGE_SOURCES}
+idf_component_register(SRCS "i80_controller_example_main.c" "lvgl_demo_ui.c" ${embedded_images}
                        INCLUDE_DIRS ".")
+
+if(CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM)
+    # Create a partition to store the image resources in the filesystem
+    spiffs_create_partition_image(storage ./images/filesystem FLASH_IN_PROJECT)
+endif()

examples/peripherals/lcd/i80_controller/main/Kconfig.projbuild

@@ -68,4 +68,16 @@ menu "Example Configuration"
             bool "FT5X06"
     endchoice
 
+    choice EXAMPLE_LCD_IMAGE_SOURCE
+        prompt "LCD image source from"
+        default EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+        help
+            Select LCD image source
+
+        config EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+            bool "File system"
+
+        config EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY
+            bool "Embedded binary"
+    endchoice
 endmenu

examples/peripherals/lcd/i80_controller/main/i80_controller_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: CC0-1.0
  */
@@ -11,13 +11,13 @@
 #include "esp_lcd_panel_io.h"
 #include "esp_lcd_panel_vendor.h"
 #include "esp_lcd_panel_ops.h"
+#include "esp_lcd_touch.h"
+#include "esp_spiffs.h"
 #include "driver/gpio.h"
+#include "driver/i2c.h"
 #include "esp_err.h"
 #include "esp_log.h"
 #include "lvgl.h"
-
-#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
-#include "driver/i2c.h"
 #if CONFIG_EXAMPLE_LCD_TOUCH_CONTROLLER_GT911
 #include "esp_lcd_touch_gt911.h"
 #elif CONFIG_EXAMPLE_LCD_TOUCH_CONTROLLER_TT21100
@@ -25,7 +25,6 @@
 #elif CONFIG_EXAMPLE_LCD_TOUCH_CONTROLLER_FT5X06
 #include "esp_lcd_touch_ft5x06.h"
 #endif
-#endif
 
 static const char *TAG = "example";
 
@@ -112,7 +111,7 @@ static void example_lvgl_flush_cb(lv_disp_drv_t *drv, const lv_area_t *area, lv_
 }
 
 #if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
-static void example_lvgl_touch_cb(lv_indev_drv_t * drv, lv_indev_data_t * data)
+static void example_lvgl_touch_cb(lv_indev_drv_t *drv, lv_indev_data_t *data)
 {
     uint16_t touchpad_x[1] = {0};
     uint16_t touchpad_y[1] = {0};
@@ -140,19 +139,46 @@ static void example_increase_lvgl_tick(void *arg)
     lv_tick_inc(EXAMPLE_LVGL_TICK_PERIOD_MS);
 }
 
-void app_main(void)
+#if CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+void example_init_filesystem(void)
 {
-    static lv_disp_draw_buf_t disp_buf; // contains internal graphic buffer(s) called draw buffer(s)
-    static lv_disp_drv_t disp_drv;      // contains callback functions
-
-    ESP_LOGI(TAG, "Turn off LCD backlight");
-    gpio_config_t bk_gpio_config = {
-        .mode = GPIO_MODE_OUTPUT,
-        .pin_bit_mask = 1ULL << EXAMPLE_PIN_NUM_BK_LIGHT
+    ESP_LOGI(TAG, "Initializing filesystem");
+    esp_vfs_spiffs_conf_t conf = {
+        .base_path = "/spiffs",
+        .partition_label = "storage",
+        .max_files = 5,
+        .format_if_mount_failed = true
     };
-    ESP_ERROR_CHECK(gpio_config(&bk_gpio_config));
-    gpio_set_level(EXAMPLE_PIN_NUM_BK_LIGHT, EXAMPLE_LCD_BK_LIGHT_OFF_LEVEL);
 
+    // Use settings defined above to initialize and mount SPIFFS filesystem.
+    // Note: esp_vfs_spiffs_register is an all-in-one convenience function.
+    esp_err_t ret = esp_vfs_spiffs_register(&conf);
+
+    if (ret != ESP_OK) {
+        if (ret == ESP_FAIL) {
+            ESP_LOGE(TAG, "Failed to mount or format filesystem");
+        } else if (ret == ESP_ERR_NOT_FOUND) {
+            ESP_LOGE(TAG, "Failed to find SPIFFS partition");
+        } else {
+            ESP_LOGE(TAG, "Failed to initialize SPIFFS (%s)", esp_err_to_name(ret));
+        }
+        return;
+    }
+
+    size_t total = 0, used = 0;
+    ret = esp_spiffs_info(conf.partition_label, &total, &used);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "Failed to get SPIFFS partition information (%s). Formatting...", esp_err_to_name(ret));
+        esp_spiffs_format(conf.partition_label);
+        return;
+    } else {
+        ESP_LOGI(TAG, "Partition size: total: %zu, used: %zu", total, used);
+    }
+}
+#endif // CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+
+void example_init_i80_bus(esp_lcd_panel_io_handle_t *io_handle, void *user_ctx)
+{
     ESP_LOGI(TAG, "Initialize Intel 8080 bus");
     esp_lcd_i80_bus_handle_t i80_bus = NULL;
     esp_lcd_i80_bus_config_t bus_config = {
@@ -185,7 +211,7 @@ void app_main(void)
         .sram_trans_align = 4,
     };
     ESP_ERROR_CHECK(esp_lcd_new_i80_bus(&bus_config, &i80_bus));
-    esp_lcd_panel_io_handle_t io_handle = NULL;
+
     esp_lcd_panel_io_i80_config_t io_config = {
         .cs_gpio_num = EXAMPLE_PIN_NUM_CS,
         .pclk_hz = EXAMPLE_LCD_PIXEL_CLOCK_HZ,
@@ -200,12 +226,15 @@ void app_main(void)
             .swap_color_bytes = !LV_COLOR_16_SWAP, // Swap can be done in LvGL (default) or DMA
         },
         .on_color_trans_done = example_notify_lvgl_flush_ready,
-        .user_ctx = &disp_drv,
+        .user_ctx = user_ctx,
         .lcd_cmd_bits = EXAMPLE_LCD_CMD_BITS,
         .lcd_param_bits = EXAMPLE_LCD_PARAM_BITS,
     };
-    ESP_ERROR_CHECK(esp_lcd_new_panel_io_i80(i80_bus, &io_config, &io_handle));
+    ESP_ERROR_CHECK(esp_lcd_new_panel_io_i80(i80_bus, &io_config, io_handle));
+}
 
+void example_init_lcd_panel(esp_lcd_panel_io_handle_t io_handle, esp_lcd_panel_handle_t *panel)
+{
     esp_lcd_panel_handle_t panel_handle = NULL;
 #if CONFIG_EXAMPLE_LCD_I80_CONTROLLER_ST7789
     ESP_LOGI(TAG, "Install LCD driver of st7789");
@@ -258,26 +287,28 @@ void app_main(void)
     // ILI9341 is very similar to ST7789 and shares the same driver.
     // Anything unconventional (such as this custom gamma table) can
     // be issued here in user code and need not modify the driver.
-    esp_lcd_panel_io_tx_param(io_handle, 0xF2, (uint8_t[]) { 0 }, 1); // 3Gamma function disable
-    esp_lcd_panel_io_tx_param(io_handle, 0x26, (uint8_t[]) { 1 }, 1); // Gamma curve 1 selected
+    esp_lcd_panel_io_tx_param(io_handle, 0xF2, (uint8_t[]) {
+        0
+    }, 1); // 3Gamma function disable
+    esp_lcd_panel_io_tx_param(io_handle, 0x26, (uint8_t[]) {
+        1
+    }, 1); // Gamma curve 1 selected
     esp_lcd_panel_io_tx_param(io_handle, 0xE0, (uint8_t[]) {          // Set positive gamma
-        0x0F, 0x31, 0x2B, 0x0C, 0x0E, 0x08, 0x4E, 0xF1, 0x37, 0x07, 0x10, 0x03, 0x0E, 0x09, 0x00 }, 15);
+        0x0F, 0x31, 0x2B, 0x0C, 0x0E, 0x08, 0x4E, 0xF1, 0x37, 0x07, 0x10, 0x03, 0x0E, 0x09, 0x00
+    }, 15);
     esp_lcd_panel_io_tx_param(io_handle, 0xE1, (uint8_t[]) {          // Set negative gamma
-        0x00, 0x0E, 0x14, 0x03, 0x11, 0x07, 0x31, 0xC1, 0x48, 0x08, 0x0F, 0x0C, 0x31, 0x36, 0x0F }, 15);
+        0x00, 0x0E, 0x14, 0x03, 0x11, 0x07, 0x31, 0xC1, 0x48, 0x08, 0x0F, 0x0C, 0x31, 0x36, 0x0F
+    }, 15);
 #endif
-
-    // user can flush pre-defined pattern to the screen before we turn on the screen or backlight
-    ESP_ERROR_CHECK(esp_lcd_panel_disp_on_off(panel_handle, true));
-
-    ESP_LOGI(TAG, "Turn on LCD backlight");
-    gpio_set_level(EXAMPLE_PIN_NUM_BK_LIGHT, EXAMPLE_LCD_BK_LIGHT_ON_LEVEL);
+    *panel = panel_handle;
+}
 
 #if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
+void example_init_lcd_touch(esp_lcd_touch_handle_t *tp_handle)
+{
     esp_lcd_touch_handle_t tp = NULL;
     esp_lcd_panel_io_handle_t tp_io_handle = NULL;
 
-    ESP_LOGI(TAG, "Initialize I2C");
-
     const i2c_config_t i2c_conf = {
         .mode = I2C_MODE_MASTER,
         .sda_io_num = EXAMPLE_I2C_SDA,
@@ -315,7 +346,6 @@ void app_main(void)
         },
     };
 
-
     /* Initialize touch */
 #if CONFIG_EXAMPLE_LCD_TOUCH_CONTROLLER_GT911
     ESP_LOGI(TAG, "Initialize touch controller GT911");
@@ -327,8 +357,48 @@ void app_main(void)
     ESP_LOGI(TAG, "Initialize touch controller FT5X06");
     ESP_ERROR_CHECK(esp_lcd_touch_new_i2c_ft5x06(tp_io_handle, &tp_cfg, &tp));
 #endif
+    *tp_handle = tp;
+}
+#endif // CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
 
-#endif
+void app_main(void)
+{
+    static lv_disp_draw_buf_t disp_buf; // contains internal graphic buffer(s) called draw buffer(s)
+    static lv_disp_drv_t disp_drv;      // contains callback functions
+
+#if EXAMPLE_PIN_NUM_BK_LIGHT >= 0
+    ESP_LOGI(TAG, "Turn off LCD backlight");
+    gpio_config_t bk_gpio_config = {
+        .mode = GPIO_MODE_OUTPUT,
+        .pin_bit_mask = 1ULL << EXAMPLE_PIN_NUM_BK_LIGHT
+    };
+    ESP_ERROR_CHECK(gpio_config(&bk_gpio_config));
+    gpio_set_level(EXAMPLE_PIN_NUM_BK_LIGHT, EXAMPLE_LCD_BK_LIGHT_OFF_LEVEL);
+#endif // EXAMPLE_PIN_NUM_BK_LIGHT >= 0
+
+#if CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+    example_init_filesystem();
+#endif // CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+
+    esp_lcd_panel_io_handle_t io_handle = NULL;
+    example_init_i80_bus(&io_handle, &disp_drv);
+
+    esp_lcd_panel_handle_t panel_handle = NULL;
+    example_init_lcd_panel(io_handle, &panel_handle);
+
+#if CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
+    esp_lcd_touch_handle_t tp_handle = NULL;
+    example_init_lcd_touch(&tp_handle);
+#endif // CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
+
+    // Stub: user can flush pre-defined pattern to the screen before we turn on the screen or backlight
+
+    ESP_ERROR_CHECK(esp_lcd_panel_disp_on_off(panel_handle, true));
+
+#if EXAMPLE_PIN_NUM_BK_LIGHT >= 0
+    ESP_LOGI(TAG, "Turn on LCD backlight");
+    gpio_set_level(EXAMPLE_PIN_NUM_BK_LIGHT, EXAMPLE_LCD_BK_LIGHT_ON_LEVEL);
+#endif // EXAMPLE_PIN_NUM_BK_LIGHT >= 0
 
     ESP_LOGI(TAG, "Initialize LVGL library");
     lv_init();
@@ -338,15 +408,12 @@ void app_main(void)
     lv_color_t *buf2 = NULL;
 #if CONFIG_EXAMPLE_LCD_I80_COLOR_IN_PSRAM
     buf1 = heap_caps_aligned_alloc(EXAMPLE_PSRAM_DATA_ALIGNMENT, EXAMPLE_LCD_H_RES * 100 * sizeof(lv_color_t), MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
-#else
-    buf1 = heap_caps_malloc(EXAMPLE_LCD_H_RES * 100 * sizeof(lv_color_t), MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL);
-#endif
-    assert(buf1);
-#if CONFIG_EXAMPLE_LCD_I80_COLOR_IN_PSRAM
     buf2 = heap_caps_aligned_alloc(EXAMPLE_PSRAM_DATA_ALIGNMENT, EXAMPLE_LCD_H_RES * 100 * sizeof(lv_color_t), MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
 #else
+    buf1 = heap_caps_malloc(EXAMPLE_LCD_H_RES * 100 * sizeof(lv_color_t), MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL);
     buf2 = heap_caps_malloc(EXAMPLE_LCD_H_RES * 100 * sizeof(lv_color_t), MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL);
-#endif
+#endif // CONFIG_EXAMPLE_LCD_I80_COLOR_IN_PSRAM
+    assert(buf1);
     assert(buf2);
     ESP_LOGI(TAG, "buf1@%p, buf2@%p", buf1, buf2);
     // initialize LVGL draw buffers
@@ -377,10 +444,9 @@ void app_main(void)
     indev_drv.type = LV_INDEV_TYPE_POINTER;
     indev_drv.disp = disp;
     indev_drv.read_cb = example_lvgl_touch_cb;
-    indev_drv.user_data = tp;
-
+    indev_drv.user_data = tp_handle;
     lv_indev_drv_register(&indev_drv);
-#endif
+#endif // CONFIG_EXAMPLE_LCD_TOUCH_ENABLED
 
     ESP_LOGI(TAG, "Display LVGL animation");
     example_lvgl_demo_ui(disp);

examples/peripherals/lcd/i80_controller/main/lvgl_demo_ui.c

@@ -1,19 +1,22 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: CC0-1.0
  */
 
 #include <math.h>
+#include "sdkconfig.h"
 #include "lvgl.h"
 
 #ifndef PI
 #define PI  (3.14159f)
 #endif
 
+#if CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY
 // LVGL image declare
 LV_IMG_DECLARE(esp_logo)
 LV_IMG_DECLARE(esp_text)
+#endif // CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY
 
 typedef struct {
     lv_obj_t *scr;
@@ -21,9 +24,9 @@ typedef struct {
 } my_timer_context_t;
 
 static my_timer_context_t my_tim_ctx;
-static lv_obj_t * btn;
+static lv_obj_t *btn;
 static lv_obj_t *arc[3];
-static lv_obj_t *img_logo;
+static lv_obj_t *img_logo = NULL;
 static lv_obj_t *img_text = NULL;
 static lv_color_t arc_color[] = {
     LV_COLOR_MAKE(232, 87, 116),
@@ -31,7 +34,6 @@ static lv_color_t arc_color[] = {
     LV_COLOR_MAKE(90, 202, 228),
 };
 
-
 static void anim_timer_cb(lv_timer_t *timer)
 {
     my_timer_context_t *timer_ctx = (my_timer_context_t *) timer->user_data;
@@ -57,7 +59,11 @@ static void anim_timer_cb(lv_timer_t *timer)
 
         // Create new image and make it transparent
         img_text = lv_img_create(scr);
+#if CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+        lv_img_set_src(img_text, "S:/spiffs/esp_text.png");
+#elif CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY
         lv_img_set_src(img_text, &esp_text);
+#endif
         lv_obj_set_style_img_opa(img_text, 0, 0);
     }
 
@@ -117,9 +123,9 @@ static void start_animation(lv_obj_t *scr)
     lv_obj_add_state(btn, LV_STATE_DISABLED);
 }
 
-static void btn_cb(lv_event_t * e)
+static void btn_cb(lv_event_t *e)
 {
-    lv_obj_t * scr = lv_event_get_user_data(e);
+    lv_obj_t *scr = lv_event_get_user_data(e);
     start_animation(scr);
 }
 
@@ -129,10 +135,13 @@ void example_lvgl_demo_ui(lv_disp_t *disp)
 
     // Create image
     img_logo = lv_img_create(scr);
+#if CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM
+    lv_img_set_src(img_logo, "S:/spiffs/esp_logo.png");
+#elif CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY
     lv_img_set_src(img_logo, &esp_logo);
-
+#endif
     btn = lv_btn_create(scr);
-    lv_obj_t * lbl = lv_label_create(btn);
+    lv_obj_t *lbl = lv_label_create(btn);
     lv_label_set_text_static(lbl, LV_SYMBOL_REFRESH" SHOW AGAIN");
     lv_obj_set_style_text_font(lbl, &lv_font_montserrat_20, 0);
     lv_obj_align(btn, LV_ALIGN_BOTTOM_LEFT, 30, -30);

examples/peripherals/lcd/i80_controller/partitions_lvgl_example.csv

@@ -0,0 +1,6 @@
+# Name,   Type, SubType, Offset,  Size, Flags
+# Note: if you have increased the bootloader size, make sure to update the offsets to avoid overlap
+nvs,      data, nvs,     0x9000,  0x6000,
+phy_init, data, phy,     0xf000,  0x1000,
+factory,  app,  factory, 0x10000, 1M,
+storage,  data, spiffs,      ,  0xF0000,

examples/peripherals/lcd/i80_controller/sdkconfig.ci.image_in_bin

@@ -0,0 +1 @@
+CONFIG_EXAMPLE_LCD_IMAGE_FROM_EMBEDDED_BINARY=y

examples/peripherals/lcd/i80_controller/sdkconfig.ci.image_in_fs

@@ -0,0 +1,11 @@
+CONFIG_EXAMPLE_LCD_IMAGE_FROM_FILE_SYSTEM=y
+
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions_lvgl_example.csv"
+
+CONFIG_LV_USE_PNG=y
+CONFIG_LV_USE_FS_POSIX=y
+
+# use 'S' (83 in ASCII) as drive letter for POSIX FS
+CONFIG_LV_FS_POSIX_LETTER=83
+CONFIG_LV_FS_POSIX_CACHE_SIZE=65535

examples/storage/spiffs/main/spiffs_example_main.c

@@ -63,7 +63,6 @@ void app_main(void)
         ESP_LOGI(TAG, "Partition size: total: %d, used: %d", total, used);
     }
 
-#
     // Check consistency of reported partiton size info.
     if (used > total) {
         ESP_LOGW(TAG, "Number of used bytes cannot be larger than total. Performing SPIFFS_check().");