CherryUSB/platform/daplink/dap_main.c

/*
 * Copyright (c) 2023 ~ 2025, sakumisu
 * Copyright (c) 2023 ~ 2025, HalfSweet
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#include "dap_main.h"
#include "DAP_config.h"
#include "DAP.h"

#define USB_CONFIG_SIZE (9 + CMSIS_DAP_INTERFACE_SIZE + CDC_ACM_DESCRIPTOR_LEN + CONFIG_MSC_DESCRIPTOR_LEN)
#define INTF_NUM        (2 + 1 + CONFIG_MSC_INTF_NUM)

__ALIGN_BEGIN const uint8_t USBD_WinUSBDescriptorSetDescriptor[] = {
        WBVAL(WINUSB_DESCRIPTOR_SET_HEADER_SIZE), /* wLength */
        WBVAL(WINUSB_SET_HEADER_DESCRIPTOR_TYPE), /* wDescriptorType */
        0x00, 0x00, 0x03, 0x06, /* >= Win 8.1 */  /* dwWindowsVersion*/
        WBVAL(USBD_WINUSB_DESC_SET_LEN),          /* wDescriptorSetTotalLength */
#if (USBD_WEBUSB_ENABLE)
        WBVAL(WINUSB_FUNCTION_SUBSET_HEADER_SIZE), // wLength
        WBVAL(WINUSB_SUBSET_HEADER_FUNCTION_TYPE), // wDescriptorType
        0,                                         // bFirstInterface USBD_WINUSB_IF_NUM
        0,                                         // bReserved
        WBVAL(FUNCTION_SUBSET_LEN),                // wSubsetLength
        WBVAL(WINUSB_FEATURE_COMPATIBLE_ID_SIZE),  // wLength
        WBVAL(WINUSB_FEATURE_COMPATIBLE_ID_TYPE),  // wDescriptorType
        'W', 'I', 'N', 'U', 'S', 'B', 0, 0,        // CompatibleId
        0, 0, 0, 0, 0, 0, 0, 0,                    // SubCompatibleId
        WBVAL(DEVICE_INTERFACE_GUIDS_FEATURE_LEN), // wLength
        WBVAL(WINUSB_FEATURE_REG_PROPERTY_TYPE),   // wDescriptorType
        WBVAL(WINUSB_PROP_DATA_TYPE_REG_MULTI_SZ), // wPropertyDataType
        WBVAL(42),                                 // wPropertyNameLength
        'D', 0, 'e', 0, 'v', 0, 'i', 0, 'c', 0, 'e', 0,
        'I', 0, 'n', 0, 't', 0, 'e', 0, 'r', 0, 'f', 0, 'a', 0, 'c', 0, 'e', 0,
        'G', 0, 'U', 0, 'I', 0, 'D', 0, 's', 0, 0, 0,
        WBVAL(80), // wPropertyDataLength
        '{', 0,
        '9', 0, '2', 0, 'C', 0, 'E', 0, '6', 0, '4', 0, '6', 0, '2', 0, '-', 0,
        '9', 0, 'C', 0, '7', 0, '7', 0, '-', 0,
        '4', 0, '6', 0, 'F', 0, 'E', 0, '-', 0,
        '9', 0, '3', 0, '3', 0, 'B', 0, '-',
        0, '3', 0, '1', 0, 'C', 0, 'B', 0, '9', 0, 'C', 0, '5', 0, 'A', 0, 'A', 0, '3', 0, 'B', 0, '9', 0,
        '}', 0, 0, 0, 0, 0
#endif
#if USBD_BULK_ENABLE
        WBVAL(WINUSB_FUNCTION_SUBSET_HEADER_SIZE), /* wLength */
        WBVAL(WINUSB_SUBSET_HEADER_FUNCTION_TYPE), /* wDescriptorType */
        0,                                         /* bFirstInterface USBD_BULK_IF_NUM*/
        0,                                         /* bReserved */
        WBVAL(FUNCTION_SUBSET_LEN),                /* wSubsetLength */
        WBVAL(WINUSB_FEATURE_COMPATIBLE_ID_SIZE),  /* wLength */
        WBVAL(WINUSB_FEATURE_COMPATIBLE_ID_TYPE),  /* wDescriptorType */
        'W', 'I', 'N', 'U', 'S', 'B', 0, 0,        /* CompatibleId*/
        0, 0, 0, 0, 0, 0, 0, 0,                    /* SubCompatibleId*/
        WBVAL(DEVICE_INTERFACE_GUIDS_FEATURE_LEN), /* wLength */
        WBVAL(WINUSB_FEATURE_REG_PROPERTY_TYPE),   /* wDescriptorType */
        WBVAL(WINUSB_PROP_DATA_TYPE_REG_MULTI_SZ), /* wPropertyDataType */
        WBVAL(42),                                 /* wPropertyNameLength */
        'D', 0, 'e', 0, 'v', 0, 'i', 0, 'c', 0, 'e', 0,
        'I', 0, 'n', 0, 't', 0, 'e', 0, 'r', 0, 'f', 0, 'a', 0, 'c', 0, 'e', 0,
        'G', 0, 'U', 0, 'I', 0, 'D', 0, 's', 0, 0, 0,
        WBVAL(80), /* wPropertyDataLength */
        '{', 0,
        'C', 0, 'D', 0, 'B', 0, '3', 0, 'B', 0, '5', 0, 'A', 0, 'D', 0, '-', 0,
        '2', 0, '9', 0, '3', 0, 'B', 0, '-', 0,
        '4', 0, '6', 0, '6', 0, '3', 0, '-', 0,
        'A', 0, 'A', 0, '3', 0, '6', 0, '-',
        0, '1', 0, 'A', 0, 'A', 0, 'E', 0, '4', 0, '6', 0, '4', 0, '6', 0, '3', 0, '7', 0, '7', 0, '6', 0,
        '}', 0, 0, 0, 0, 0
#endif
};

__ALIGN_BEGIN const uint8_t USBD_BinaryObjectStoreDescriptor[] = {
        0x05,                         /* bLength */
        0x0f,                         /* bDescriptorType */
        WBVAL(USBD_BOS_WTOTALLENGTH), /* wTotalLength */
        USBD_NUM_DEV_CAPABILITIES,    /* bNumDeviceCaps */
#if (USBD_WEBUSB_ENABLE)
        USBD_WEBUSB_DESC_LEN,           /* bLength */
        0x10,                           /* bDescriptorType */
        USB_DEVICE_CAPABILITY_PLATFORM, /* bDevCapabilityType */
        0x00,                           /* bReserved */
        0x38, 0xB6, 0x08, 0x34,         /* PlatformCapabilityUUID */
        0xA9, 0x09, 0xA0, 0x47,
        0x8B, 0xFD, 0xA0, 0x76,
        0x88, 0x15, 0xB6, 0x65,
        WBVAL(0x0100), /* 1.00 */ /* bcdVersion */
        USBD_WINUSB_VENDOR_CODE,  /* bVendorCode */
        0,                        /* iLandingPage */
#endif
#if (USBD_WINUSB_ENABLE)
        USBD_WINUSB_DESC_LEN,           /* bLength */
        0x10,                           /* bDescriptorType */
        USB_DEVICE_CAPABILITY_PLATFORM, /* bDevCapabilityType */
        0x00,                           /* bReserved */
        0xDF, 0x60, 0xDD, 0xD8,         /* PlatformCapabilityUUID */
        0x89, 0x45, 0xC7, 0x4C,
        0x9C, 0xD2, 0x65, 0x9D,
        0x9E, 0x64, 0x8A, 0x9F,
        0x00, 0x00, 0x03, 0x06, /* >= Win 8.1 */ /* dwWindowsVersion*/
        WBVAL(USBD_WINUSB_DESC_SET_LEN),         /* wDescriptorSetTotalLength */
        USBD_WINUSB_VENDOR_CODE,                 /* bVendorCode */
        0,                                       /* bAltEnumCode */
#endif
};

static const uint8_t device_descriptor[] = {
        USB_DEVICE_DESCRIPTOR_INIT(USB_2_1, 0xEF, 0x02, 0x01, USBD_VID, USBD_PID, 0x0100, 0x01),
};

static const uint8_t config_descriptor[] = {
        USB_CONFIG_DESCRIPTOR_INIT(USB_CONFIG_SIZE, INTF_NUM, 0x01, USB_CONFIG_BUS_POWERED, USBD_MAX_POWER),
        /* Interface 0 */
        USB_INTERFACE_DESCRIPTOR_INIT(0x00, 0x00, 0x02, 0xFF, 0x00, 0x00, 0x02),
        /* Endpoint OUT 2 */
        USB_ENDPOINT_DESCRIPTOR_INIT(DAP_OUT_EP, USB_ENDPOINT_TYPE_BULK, DAP_PACKET_SIZE, 0x00),
        /* Endpoint IN 1 */
        USB_ENDPOINT_DESCRIPTOR_INIT(DAP_IN_EP, USB_ENDPOINT_TYPE_BULK, DAP_PACKET_SIZE, 0x00),
        CDC_ACM_DESCRIPTOR_INIT(0x01, CDC_INT_EP, CDC_OUT_EP, CDC_IN_EP, DAP_PACKET_SIZE, 0x00),
#ifdef CONFIG_CHERRYDAP_USE_MSC
        MSC_DESCRIPTOR_INIT(MSC_INTF_NUM, MSC_OUT_EP, MSC_IN_EP, DAP_PACKET_SIZE, 0x00),
#endif
};

static const uint8_t other_speed_config_descriptor[] = {
        USB_CONFIG_DESCRIPTOR_INIT(USB_CONFIG_SIZE, INTF_NUM, 0x01, USB_CONFIG_BUS_POWERED, USBD_MAX_POWER),
        /* Interface 0 */
        USB_INTERFACE_DESCRIPTOR_INIT(0x00, 0x00, 0x02, 0xFF, 0x00, 0x00, 0x02),
        /* Endpoint OUT 2 */
        USB_ENDPOINT_DESCRIPTOR_INIT(DAP_OUT_EP, USB_ENDPOINT_TYPE_BULK, DAP_PACKET_SIZE, 0x00),
        /* Endpoint IN 1 */
        USB_ENDPOINT_DESCRIPTOR_INIT(DAP_IN_EP, USB_ENDPOINT_TYPE_BULK, DAP_PACKET_SIZE, 0x00),
        CDC_ACM_DESCRIPTOR_INIT(0x01, CDC_INT_EP, CDC_OUT_EP, CDC_IN_EP, DAP_PACKET_SIZE, 0x00),
#ifdef CONFIG_CHERRYDAP_USE_MSC
        MSC_DESCRIPTOR_INIT(MSC_INTF_NUM, MSC_OUT_EP, MSC_IN_EP, DAP_PACKET_SIZE, 0x00),
#endif
};

char *string_descriptors[] = {
        (char[]) {0x09, 0x04},             /* Langid */
        "CherryUSB",                        /* Manufacturer */
        "CherryUSB CMSIS-DAP",              /* Product */
        "00000000000000000123456789ABCDEF", /* Serial Number */
};

static const uint8_t device_quality_descriptor[] = {
        USB_DEVICE_QUALIFIER_DESCRIPTOR_INIT(USB_2_1, 0x00, 0x00, 0x00, 0x01),
};

__WEAK const uint8_t *device_descriptor_callback(uint8_t speed)
{
    (void) speed;
    return device_descriptor;
}

__WEAK const uint8_t *config_descriptor_callback(uint8_t speed)
{
    (void) speed;
    return config_descriptor;
}

__WEAK const uint8_t *device_quality_descriptor_callback(uint8_t speed)
{
    (void) speed;
    return device_quality_descriptor;
}

__WEAK const uint8_t *other_speed_config_descriptor_callback(uint8_t speed)
{
    (void) speed;
    return other_speed_config_descriptor;
}

__WEAK const char *string_descriptor_callback(uint8_t speed, uint8_t index)
{
    (void) speed;

    if (index >= (sizeof(string_descriptors) / sizeof(char *))) {
        return NULL;
    }
    return string_descriptors[index];
}

static volatile uint16_t USB_RequestIndexI = 0; // Request  Index In
static volatile uint16_t USB_RequestIndexO = 0; // Request  Index Out
static volatile uint16_t USB_RequestCountI = 0; // Request  Count In
static volatile uint16_t USB_RequestCountO = 0; // Request  Count Out
static volatile uint8_t USB_RequestIdle = 1;    // Request  Idle  Flag

static volatile uint16_t USB_ResponseIndexI = 0; // Response Index In
static volatile uint16_t USB_ResponseIndexO = 0; // Response Index Out
static volatile uint16_t USB_ResponseCountI = 0; // Response Count In
static volatile uint16_t USB_ResponseCountO = 0; // Response Count Out
static volatile uint8_t USB_ResponseIdle = 1;    // Response Idle  Flag

static USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t USB_Request[DAP_PACKET_COUNT][DAP_PACKET_SIZE];  // Request  Buffer
static USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t USB_Response[DAP_PACKET_COUNT][DAP_PACKET_SIZE]; // Response Buffer
static uint16_t USB_RespSize[DAP_PACKET_COUNT];                                                        // Response Size

volatile struct cdc_line_coding g_cdc_lincoding;
volatile uint8_t config_uart = 0;
volatile uint8_t config_uart_transfer = 0;

USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t uartrx_ringbuffer[CONFIG_UARTRX_RINGBUF_SIZE];
USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t usbrx_ringbuffer[CONFIG_USBRX_RINGBUF_SIZE];
USB_NOCACHE_RAM_SECTION USB_MEM_ALIGNX uint8_t usb_tmpbuffer[DAP_PACKET_SIZE];

static volatile uint8_t usbrx_idle_flag = 0;
static volatile uint8_t usbtx_idle_flag = 0;
static volatile uint8_t uarttx_idle_flag = 0;

USB_NOCACHE_RAM_SECTION chry_ringbuffer_t g_uartrx;
USB_NOCACHE_RAM_SECTION chry_ringbuffer_t g_usbrx;

void usbd_event_handler(uint8_t busid, uint8_t event)
{
    (void) busid;
    switch (event) {
        case USBD_EVENT_RESET:
            usbrx_idle_flag = 0;
            usbtx_idle_flag = 0;
            uarttx_idle_flag = 0;
            config_uart_transfer = 0;
            break;
        case USBD_EVENT_CONNECTED:
            break;
        case USBD_EVENT_DISCONNECTED:
            break;
        case USBD_EVENT_RESUME:
            break;
        case USBD_EVENT_SUSPEND:
            break;
        case USBD_EVENT_CONFIGURED:
            /* setup first out ep read transfer */
            USB_RequestIdle = 0U;

            usbd_ep_start_read(0, DAP_OUT_EP, USB_Request[0], DAP_PACKET_SIZE);
            usbd_ep_start_read(0, CDC_OUT_EP, usb_tmpbuffer, DAP_PACKET_SIZE);

            break;
        case USBD_EVENT_SET_REMOTE_WAKEUP:
            break;
        case USBD_EVENT_CLR_REMOTE_WAKEUP:
            break;

        default:
            break;
    }
}

void dap_out_callback(uint8_t busid, uint8_t ep, uint32_t nbytes)
{
    (void) busid;
    if (USB_Request[USB_RequestIndexI][0] == ID_DAP_TransferAbort) {
        DAP_TransferAbort = 1U;
    } else {
        USB_RequestIndexI++;
        if (USB_RequestIndexI == DAP_PACKET_COUNT) {
            USB_RequestIndexI = 0U;
        }
        USB_RequestCountI++;
    }

    // Start reception of next request packet
    if ((uint16_t) (USB_RequestCountI - USB_RequestCountO) != DAP_PACKET_COUNT) {
        usbd_ep_start_read(0, DAP_OUT_EP, USB_Request[USB_RequestIndexI], DAP_PACKET_SIZE);
    } else {
        USB_RequestIdle = 1U;
    }
}

void dap_in_callback(uint8_t busid, uint8_t ep, uint32_t nbytes)
{
    (void) busid;
    if (USB_ResponseCountI != USB_ResponseCountO) {
        // Load data from response buffer to be sent back
        usbd_ep_start_write(0, DAP_IN_EP, USB_Response[USB_ResponseIndexO], USB_RespSize[USB_ResponseIndexO]);
        USB_ResponseIndexO++;
        if (USB_ResponseIndexO == DAP_PACKET_COUNT) {
            USB_ResponseIndexO = 0U;
        }
        USB_ResponseCountO++;
    } else {
        USB_ResponseIdle = 1U;
    }
}

void usbd_cdc_acm_bulk_out(uint8_t busid, uint8_t ep, uint32_t nbytes)
{
    (void) busid;
    chry_ringbuffer_write(&g_usbrx, usb_tmpbuffer, nbytes);
    if (chry_ringbuffer_get_free(&g_usbrx) >= DAP_PACKET_SIZE) {
        usbd_ep_start_read(0, CDC_OUT_EP, usb_tmpbuffer, DAP_PACKET_SIZE);
    } else {
        usbrx_idle_flag = 1;
    }
}

void usbd_cdc_acm_bulk_in(uint8_t busid, uint8_t ep, uint32_t nbytes)
{
    (void) busid;
    uint32_t size;
    uint8_t *buffer;

    chry_ringbuffer_linear_read_done(&g_uartrx, nbytes);
    if ((nbytes % DAP_PACKET_SIZE) == 0 && nbytes) {
        /* send zlp */
        usbd_ep_start_write(0, CDC_IN_EP, NULL, 0);
    } else {
        if (chry_ringbuffer_get_used(&g_uartrx)) {
            buffer = chry_ringbuffer_linear_read_setup(&g_uartrx, &size);
            usbd_ep_start_write(0, CDC_IN_EP, buffer, size);
        } else {
            usbtx_idle_flag = 1;
        }
    }
}

struct usbd_endpoint dap_out_ep = {
        .ep_addr = DAP_OUT_EP,
        .ep_cb = dap_out_callback
};

struct usbd_endpoint dap_in_ep = {
        .ep_addr = DAP_IN_EP,
        .ep_cb = dap_in_callback
};

struct usbd_endpoint cdc_out_ep = {
        .ep_addr = CDC_OUT_EP,
        .ep_cb = usbd_cdc_acm_bulk_out
};

struct usbd_endpoint cdc_in_ep = {
        .ep_addr = CDC_IN_EP,
        .ep_cb = usbd_cdc_acm_bulk_in
};

struct usbd_interface dap_intf;
struct usbd_interface intf1;
struct usbd_interface intf2;
struct usbd_interface intf3;
struct usbd_interface hid_intf;

struct usb_msosv2_descriptor msosv2_desc = {
        .vendor_code = USBD_WINUSB_VENDOR_CODE,
        .compat_id = USBD_WinUSBDescriptorSetDescriptor,
        .compat_id_len = USBD_WINUSB_DESC_SET_LEN,
};

struct usb_bos_descriptor bos_desc = {
        .string = USBD_BinaryObjectStoreDescriptor,
        .string_len = USBD_BOS_WTOTALLENGTH
};

const struct usb_descriptor cmsisdap_descriptor = {
        .device_descriptor_callback = device_descriptor_callback,
        .config_descriptor_callback = config_descriptor_callback,
        .device_quality_descriptor_callback = device_quality_descriptor_callback,
        .other_speed_descriptor_callback = other_speed_config_descriptor_callback,
        .string_descriptor_callback = string_descriptor_callback,
        .bos_descriptor = &bos_desc,
        .msosv2_descriptor = &msosv2_desc,
};

void chry_dap_handle(void)
{
    uint32_t n;

    // Process pending requests
    while (USB_RequestCountI != USB_RequestCountO) {
        // Handle Queue Commands
        n = USB_RequestIndexO;
        while (USB_Request[n][0] == ID_DAP_QueueCommands) {
            USB_Request[n][0] = ID_DAP_ExecuteCommands;
            n++;
            if (n == DAP_PACKET_COUNT) {
                n = 0U;
            }
            if (n == USB_RequestIndexI) {
                // flags = osThreadFlagsWait(0x81U, osFlagsWaitAny, osWaitForever);
                // if (flags & 0x80U) {
                //     break;
                // }
            }
        }

        // Execute DAP Command (process request and prepare response)
        USB_RespSize[USB_ResponseIndexI] =
                (uint16_t) DAP_ExecuteCommand(USB_Request[USB_RequestIndexO], USB_Response[USB_ResponseIndexI]);

        // Update Request Index and Count
        USB_RequestIndexO++;
        if (USB_RequestIndexO == DAP_PACKET_COUNT) {
            USB_RequestIndexO = 0U;
        }
        USB_RequestCountO++;

        if (USB_RequestIdle) {
            if ((uint16_t) (USB_RequestCountI - USB_RequestCountO) != DAP_PACKET_COUNT) {
                USB_RequestIdle = 0U;
                usbd_ep_start_read(0, DAP_OUT_EP, USB_Request[USB_RequestIndexI], DAP_PACKET_SIZE);
            }
        }

        // Update Response Index and Count
        USB_ResponseIndexI++;
        if (USB_ResponseIndexI == DAP_PACKET_COUNT) {
            USB_ResponseIndexI = 0U;
        }
        USB_ResponseCountI++;

        if (USB_ResponseIdle) {
            if (USB_ResponseCountI != USB_ResponseCountO) {
                // Load data from response buffer to be sent back
                n = USB_ResponseIndexO++;
                if (USB_ResponseIndexO == DAP_PACKET_COUNT) {
                    USB_ResponseIndexO = 0U;
                }
                USB_ResponseCountO++;
                USB_ResponseIdle = 0U;
                usbd_ep_start_write(0, DAP_IN_EP, USB_Response[n], USB_RespSize[n]);
            }
        }
    }
}

void usbd_cdc_acm_set_line_coding(uint8_t busid, uint8_t intf, struct cdc_line_coding *line_coding)
{
    (void) busid;
    if (memcmp(line_coding, (uint8_t *) &g_cdc_lincoding, sizeof(struct cdc_line_coding)) != 0) {
        memcpy((uint8_t *) &g_cdc_lincoding, line_coding, sizeof(struct cdc_line_coding));
        config_uart = 1;
        config_uart_transfer = 0;
    }
}

void usbd_cdc_acm_get_line_coding(uint8_t busid, uint8_t intf, struct cdc_line_coding *line_coding)
{
    (void) busid;
    memcpy(line_coding, (uint8_t *) &g_cdc_lincoding, sizeof(struct cdc_line_coding));
}

void chry_dap_usb2uart_handle(void)
{
    uint32_t size;
    uint8_t *buffer;

    if (config_uart) {
        /* disable irq here */
        config_uart = 0;
        /* config uart here */
        chry_dap_usb2uart_uart_config_callback((struct cdc_line_coding *) &g_cdc_lincoding);
        usbtx_idle_flag = 1;
        uarttx_idle_flag = 1;
        config_uart_transfer = 1;
        //chry_ringbuffer_reset_read(&g_uartrx);
        /* enable irq here */
    }

    if (config_uart_transfer == 0) {
        return;
    }

    /* why we use chry_ringbuffer_linear_read_setup?
     * becase we use dma and we do not want to use temp buffer to memcpy from ringbuffer
     *
    */

    /* uartrx to usb tx */
    if (usbtx_idle_flag) {
        if (chry_ringbuffer_get_used(&g_uartrx)) {
            usbtx_idle_flag = 0;
            /* start first transfer */
            buffer = chry_ringbuffer_linear_read_setup(&g_uartrx, &size);
            usbd_ep_start_write(0, CDC_IN_EP, buffer, size);
        }
    }

    /* usbrx to uart tx */
    if (uarttx_idle_flag) {
        if (chry_ringbuffer_get_used(&g_usbrx)) {
            uarttx_idle_flag = 0;
            /* start first transfer */
            buffer = chry_ringbuffer_linear_read_setup(&g_usbrx, &size);
            chry_dap_usb2uart_uart_send_bydma(buffer, size);
        }
    }

    /* check whether usb rx ringbuffer have space to store */
    if (usbrx_idle_flag) {
        if (chry_ringbuffer_get_free(&g_usbrx) >= DAP_PACKET_SIZE) {
            usbrx_idle_flag = 0;
            usbd_ep_start_read(0, CDC_OUT_EP, usb_tmpbuffer, DAP_PACKET_SIZE);
        }
    }
}

/* implment by user */
__WEAK void chry_dap_usb2uart_uart_config_callback(struct cdc_line_coding *line_coding)
{
}

/* called by user */
void chry_dap_usb2uart_uart_send_complete(uint32_t size)
{
    uint8_t *buffer;

    chry_ringbuffer_linear_read_done(&g_usbrx, size);

    if (chry_ringbuffer_get_used(&g_usbrx)) {
        buffer = chry_ringbuffer_linear_read_setup(&g_usbrx, &size);
        chry_dap_usb2uart_uart_send_bydma(buffer, size);
    } else {
        uarttx_idle_flag = 1;
    }
}

/* implment by user */
__WEAK void chry_dap_usb2uart_uart_send_bydma(uint8_t *data, uint16_t len)
{
}

#ifdef CONFIG_CHERRYDAP_USE_MSC
#define BLOCK_SIZE  512
#define BLOCK_COUNT 10

typedef struct
{
    uint8_t BlockSpace[BLOCK_SIZE];
} BLOCK_TYPE;

BLOCK_TYPE mass_block[BLOCK_COUNT];

void usbd_msc_get_cap(uint8_t lun, uint32_t *block_num, uint16_t *block_size)
{
    *block_num = 1000; //Pretend having so many buffer,not has actually.
    *block_size = BLOCK_SIZE;
}
int usbd_msc_sector_read(uint32_t sector, uint8_t *buffer, uint32_t length)
{
    if (sector < 10)
        memcpy(buffer, mass_block[sector].BlockSpace, length);
    return 0;
}

int usbd_msc_sector_write(uint32_t sector, uint8_t *buffer, uint32_t length)
{
    if (sector < 10)
        memcpy(mass_block[sector].BlockSpace, buffer, length);
    return 0;
}
#endif