10 CherryUSB怎样实现U盘动态加载

/* assume the block device is 512M */
#define BLOCK_DEV_NAME      "filesys"
#define BLOCK_SIZE          4096
#define BLOCK_COUNT         (7 * 1024 * 1024 / BLOCK_SIZE)
static rt_device_t blk_dev = RT_NULL;
static void usbd_event_handler(uint8_t busid, uint8_t event)
{
    switch (event) {
        case USBD_EVENT_RESET:
            break;
        case USBD_EVENT_CONNECTED:
            //卸载文件系统
            //挂载U盘
            break;
        case USBD_EVENT_DISCONNECTED:
            //卸载U盘
            //挂载文件系统
            break;
        case USBD_EVENT_RESUME:
            break;
        case USBD_EVENT_SUSPEND:
            break;
        case USBD_EVENT_CONFIGURED:
            break;
        case USBD_EVENT_SET_REMOTE_WAKEUP:
            break;
        case USBD_EVENT_CLR_REMOTE_WAKEUP:
            break;
        default:
            break;
    }
}