STM32 USB OTG HOST 庫在嘗試使用 FatFs 創建文件時掛起

Question

我正在嘗試在 USB 閃存上創建一個帶有 FatFs 的文件，但是我的f_open調用試圖讀取引導扇區以進行第一次文件系統掛載時掛在這個函數上。

DRESULT disk_read (
                   BYTE drv,            /* Physical drive number (0) */
                   BYTE *buff,          /* Pointer to the data buffer to store read data */
                   DWORD sector,        /* Start sector number (LBA) */
                   BYTE count           /* Sector count (1..255) */
                     )
{
  BYTE status = USBH_MSC_OK;
  
  if (drv || !count) return RES_PARERR;
  if (Stat & STA_NOINIT) return RES_NOTRDY;
  
  
  if(HCD_IsDeviceConnected(&USB_OTG_Core))
  {  
    
    do
    {
      status = USBH_MSC_Read10(&USB_OTG_Core, buff,sector,512 * count);
      USBH_MSC_HandleBOTXfer(&USB_OTG_Core ,&USB_Host);
      
      if(!HCD_IsDeviceConnected(&USB_OTG_Core))
      { 
        return RES_ERROR;
      }      
    }
    while(status == USBH_MSC_BUSY ); // Loop which create hanging state
  }
  
  if(status == USBH_MSC_OK)
    return RES_OK;
  return RES_ERROR;
  
}

主要問題是創建掛起狀態的循環

while(status == USBH_MSC_BUSY );

所以我不知道該怎么做才能避免這種情況。 使用調試器我發現狀態是由結構USBH_MSC_BOTXferParam的參數CmdStateMachine引起的，類型USBH_BOTXfer_TypeDef等於CMD_UNINITIALIZED_STATE這實際上導致錯過了USBH_MSC_Read10函數的 switch 語句。

/**
  * @brief  USBH_MSC_Read10 
  *         Issue the read command to the device. Once the response received, 
  *         it updates the status to upper layer
  * @param  dataBuffer : DataBuffer will contain the data to be read
  * @param  address : Address from which the data will be read
  * @param  nbOfbytes : NbOfbytes to be read
  * @retval Status
  */
uint8_t USBH_MSC_Read10(USB_OTG_CORE_HANDLE *pdev,
                        uint8_t *dataBuffer,
                        uint32_t address,
                        uint32_t nbOfbytes)
{
  uint8_t index;
  static USBH_MSC_Status_TypeDef status = USBH_MSC_BUSY;
  uint16_t nbOfPages;
  status = USBH_MSC_BUSY;
  
  if(HCD_IsDeviceConnected(pdev))
  {
    switch(USBH_MSC_BOTXferParam.CmdStateMachine)
    {
    case CMD_SEND_STATE:
      /*Prepare the CBW and relevant field*/
      USBH_MSC_CBWData.field.CBWTransferLength = nbOfbytes;
      USBH_MSC_CBWData.field.CBWFlags = USB_EP_DIR_IN;
      USBH_MSC_CBWData.field.CBWLength = CBW_LENGTH;
      
      USBH_MSC_BOTXferParam.pRxTxBuff = dataBuffer;
      
      for(index = CBW_CB_LENGTH; index != 0; index--)
      {
        USBH_MSC_CBWData.field.CBWCB[index] = 0x00;
      }
      
      USBH_MSC_CBWData.field.CBWCB[0]  = OPCODE_READ10; 
      
      /*logical block address*/
      
      USBH_MSC_CBWData.field.CBWCB[2]  = (((uint8_t*)&address)[3]);
      USBH_MSC_CBWData.field.CBWCB[3]  = (((uint8_t*)&address)[2]);
      USBH_MSC_CBWData.field.CBWCB[4]  = (((uint8_t*)&address)[1]);
      USBH_MSC_CBWData.field.CBWCB[5]  = (((uint8_t*)&address)[0]);
      
      /*USBH_MSC_PAGE_LENGTH = 512*/
      nbOfPages = nbOfbytes/ USBH_MSC_PAGE_LENGTH;  
      
      /*Tranfer length */
      USBH_MSC_CBWData.field.CBWCB[7]  = (((uint8_t *)&nbOfPages)[1]) ; 
      USBH_MSC_CBWData.field.CBWCB[8]  = (((uint8_t *)&nbOfPages)[0]) ; 
      
      
      USBH_MSC_BOTXferParam.BOTState = USBH_MSC_SEND_CBW;
      /* Start the transfer, then let the state machine 
      manage the other transactions */
      USBH_MSC_BOTXferParam.MSCState = USBH_MSC_BOT_USB_TRANSFERS;
      USBH_MSC_BOTXferParam.BOTXferStatus = USBH_MSC_BUSY;
      USBH_MSC_BOTXferParam.CmdStateMachine = CMD_WAIT_STATUS;
      
      status = USBH_MSC_BUSY;
      
      break;
      
    case CMD_WAIT_STATUS:
      
      if((USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_OK) && \
        (HCD_IsDeviceConnected(pdev)))
      { 
        /* Commands successfully sent and Response Received  */       
        USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
        status = USBH_MSC_OK;      
      }
      else if (( USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_FAIL ) && \
        (HCD_IsDeviceConnected(pdev)))
      {
        /* Failure Mode */
        USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
      }
      
      else if ( USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_PHASE_ERROR )
      {
        /* Failure Mode */
        USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
        status = USBH_MSC_PHASE_ERROR;    
      }
      else
      {
        /* Wait for the Commands to get Completed */
        /* NO Change in state Machine */
      }
      break;
      
    default:
      break;
    }
  }
  return status;
}

這里是USBH_BOTXfer_TypeDef類型聲明；

typedef struct _BOTXfer
{
uint8_t MSCState;
uint8_t MSCStateBkp;
uint8_t MSCStateCurrent;
uint8_t CmdStateMachine;
uint8_t BOTState;
uint8_t BOTStateBkp;
uint8_t* pRxTxBuff;
uint16_t DataLength;
uint8_t BOTXferErrorCount;
uint8_t BOTXferStatus;
} USBH_BOTXfer_TypeDef;

在調試過程中我發現它的所有字段都是0x00。

這是我的 FatFs 電話

int main(void)
{
    FATFS Fat;
    FIL file;
    FRESULT fr;
    
    RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN;
    
    /* Enable SWO output */
    DBGMCU->CR = 0x00000020;
    
    GPIOD->MODER=0x55000000;
    GPIOD->OTYPER = 0x00000000;
    GPIOD->OSPEEDR = 0x00000001;
    
    while(1)
    {   
        if (!USB_MSC_IsInitialized())
        {
            USB_MSC_Initialize();
        }
        
        if (USB_MSC_IsConnected())
        {
            GPIOD->ODR = (1 << 15);
            
            disk_initialize(0);
            
            fr = f_mount(0, &Fat);
            
            if(fr == FR_OK)
            {           
                fr = f_open(&file,"0:DP_lab8.pdf",(FA_CREATE_ALWAYS | FA_WRITE));
                
                if (fr == FR_OK)
                {
                    f_close(&file);
                }
                
                f_mount(0, NULL);
            }
        }
        else
        {
            GPIOD->ODR = (1 << 14);
        }
        
        USB_MSC_Main();
    }
}

USB_MSC_IsConnected函數是：

int USB_MSC_IsConnected(void)
{
    if (g_USB_MSC_HostStatus == USB_DEV_NOT_SUPPORTED)
    {
        USB_MSC_Uninitialize();
    }
    
    return !(g_USB_MSC_HostStatus == USB_DEV_DETACHED ||
        g_USB_MSC_HostStatus == USB_HOST_NO_INIT ||
      g_USB_MSC_HostStatus == USB_DEV_NOT_SUPPORTED);
}

設備狀態是：

typedef enum
{
    USB_HOST_NO_INIT = 0,  /* USB interface not initialized */
    USB_DEV_DETACHED,      /* no device connected */
    USB_SPEED_ERROR,       /* unsupported USB speed */
    USB_DEV_NOT_SUPPORTED, /* unsupported device */
    USB_DEV_WRITE_PROTECT, /* device is write protected */
    USB_OVER_CURRENT,      /* overcurrent detected */
    USB_DEV_CONNECTED      /* device connected and ready */
} USB_HostStatus;

g_USB_MSC_HostStatus的值由標准 USB HOST 用戶回調接收。

Answer 1

我認為這是 ST 主機庫中的錯誤。 我已經找到它了，因為我的 USB 主機無法通過枚舉階段。 修復后堆棧正常。

在“STM32Cube/Repository/STM32Cube_FW_F7_V1.13.0/Middlewares/ST/STM32_USB_Host_Library/Core/Inc”（任何芯片，不僅是F7，任何版本，不僅是V1.13.0）中的usbh_def.h文件中有union _USB_Setup 。 它有 uint16_t bmRequestType 和 uint16_t bRequest。 根據 USB 規范，這兩個字段必須是 uint8_t。 解決此問題使 USB 主機按需運行。 枚舉階段順利通過，所有其他階段也是如此。