LittleFS filesystem for the ESP32

LittleFlash is a port of LittleFS to the ESP32, providing support for usage on internal and external flash. External support utilizes my ExtFlash component.

To clone this repo, use the following to automatically include the extflash submodule:

git clone --recurse-submodules https://github.com/lllucius/esp32_littleflash

To use, just add the "extflash" and "littleflash" components to your components directory and initialize it with something like:

#include "littleflash.h"

void app_main()
{
    esp_err_t err;

#if !defined(CONFIG_LITTLEFS_PARTITION_LABEL)
    ExtFlash flash;

    ext_flash_config_t cfg =
    {
        .vspi = true,
        .sck_io_num = PIN_SPI_SCK,
        .miso_io_num = PIN_SPI_MISO,
        .mosi_io_num = PIN_SPI_MOSI,
        .ss_io_num = PIN_SPI_SS,
        .hd_io_num = PIN_SPI_HD,
        .wp_io_num = PIN_SPI_WP,
        .speed_mhz = 40,
        .dma_channel = 1,
        .queue_size = 2,
        .sector_size = 0,
        .capacity = 0
    };

    err = flash.init(&cfg);
    if (err != ESP_OK)
    {
        ...
    }
#endif

    const little_flash_config_t little_cfg =
    {
#if !defined(CONFIG_LITTLEFS_PARTITION_LABEL)
        .flash = &extflash,
        .part_label = NULL,
#else
        .flash = NULL,
        .part_label = CONFIG_LITTLEFS_PARTITION_LABEL,
#endif
        .base_path = MOUNT_POINT,
        .open_files = openfiles,
        .auto_format = true,
        .lookahead = 32
    };

    err = littleflash.init(&little_cfg);
    if (err != ESP_OK)
    {
        ...
    }
    ...
}

The configuration options for LittleFlash are:

typedef struct
{
    ExtFlash *flash;            // initialized ExtFlash, or NULL for internal flash
    const char *part_label;     // partition label if using internal flash
    const char *base_path;      // mount point
    int open_files;             // number of open files to support
    bool auto_format;           // true=format if not valid
    lfs_size_t lookahead;       // number of LFS lookahead blocks
} little_flash_config_t;

More documentation to follow.