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mpstate.h

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  • usbd_req.c 20.41 KiB
    /**
      ******************************************************************************
      * @file    usbd_req.c
      * @author  MCD Application Team
      * @version V1.1.0
      * @date    19-March-2012 
      * @brief   This file provides the standard USB requests following chapter 9.
      ******************************************************************************
      * @attention
      *
      * <h2><center>&copy; COPYRIGHT 2012 STMicroelectronics</center></h2>
      *
      * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
      * You may not use this file except in compliance with the License.
      * You may obtain a copy of the License at:
      *
      *        http://www.st.com/software_license_agreement_liberty_v2
      *
      * Unless required by applicable law or agreed to in writing, software 
      * distributed under the License is distributed on an "AS IS" BASIS, 
      * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      * See the License for the specific language governing permissions and
      * limitations under the License.
      *
      ******************************************************************************
      */ 
    
    /* Includes ------------------------------------------------------------------*/
    #include "usbd_req.h"
    #include "usbd_ioreq.h"
    #include "usbd_desc.h"
    
    
    /** @addtogroup STM32_USB_OTG_DEVICE_LIBRARY
      * @{
      */
    
    
    /** @defgroup USBD_REQ 
      * @brief USB standard requests module
      * @{
      */ 
    
    /** @defgroup USBD_REQ_Private_TypesDefinitions
      * @{
      */ 
    /**
      * @}
      */ 
    
    
    /** @defgroup USBD_REQ_Private_Defines
      * @{
      */ 
    
    /**
      * @}
      */ 
    
    
    /** @defgroup USBD_REQ_Private_Macros
      * @{
      */ 
    /**
      * @}
      */ 
    
    
    /** @defgroup USBD_REQ_Private_Variables
      * @{
      */ 
    extern __IO USB_OTG_DCTL_TypeDef SET_TEST_MODE;
    
    #ifdef USB_OTG_HS_INTERNAL_DMA_ENABLED
      #if defined ( __ICCARM__ ) /*!< IAR Compiler */
        #pragma data_alignment=4   
      #endif
    #endif /* USB_OTG_HS_INTERNAL_DMA_ENABLED */  
    __ALIGN_BEGIN uint32_t USBD_ep_status __ALIGN_END  = 0; 
    
    #ifdef USB_OTG_HS_INTERNAL_DMA_ENABLED
      #if defined ( __ICCARM__ ) /*!< IAR Compiler */
        #pragma data_alignment=4   
      #endif
    #endif /* USB_OTG_HS_INTERNAL_DMA_ENABLED */
    __ALIGN_BEGIN uint32_t  USBD_default_cfg __ALIGN_END  = 0;
    
    #ifdef USB_OTG_HS_INTERNAL_DMA_ENABLED
      #if defined ( __ICCARM__ ) /*!< IAR Compiler */
        #pragma data_alignment=4   
      #endif
    #endif /* USB_OTG_HS_INTERNAL_DMA_ENABLED */
    __ALIGN_BEGIN uint32_t  USBD_cfg_status __ALIGN_END  = 0;  
    
    #ifdef USB_OTG_HS_INTERNAL_DMA_ENABLED
      #if defined ( __ICCARM__ ) /*!< IAR Compiler */
        #pragma data_alignment=4   
      #endif
    #endif /* USB_OTG_HS_INTERNAL_DMA_ENABLED */
    __ALIGN_BEGIN uint8_t USBD_StrDesc[USB_MAX_STR_DESC_SIZ] __ALIGN_END ;
    /**
      * @}
      */ 
    
    
    /** @defgroup USBD_REQ_Private_FunctionPrototypes
      * @{
      */ 
    static void USBD_GetDescriptor(USB_OTG_CORE_HANDLE  *pdev, 
                                   USB_SETUP_REQ *req);
    
    static void USBD_SetAddress(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req);
    
    static void USBD_SetConfig(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req);
    
    static void USBD_GetConfig(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req);
    
    static void USBD_GetStatus(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req);
    
    static void USBD_SetFeature(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req);
    
    static void USBD_ClrFeature(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req);
    
    static uint8_t USBD_GetLen(const char *buf);
    /**
      * @}
      */ 
    
    
    /** @defgroup USBD_REQ_Private_Functions
      * @{
      */ 
    
    
    /**
    * @brief  USBD_StdDevReq
    *         Handle standard usb device requests
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    USBD_Status  USBD_StdDevReq (USB_OTG_CORE_HANDLE  *pdev, USB_SETUP_REQ  *req)
    {
      USBD_Status ret = USBD_OK;  
      
      switch (req->bRequest) 
      {
      case USB_REQ_GET_DESCRIPTOR: 
        
        USBD_GetDescriptor (pdev, req) ;
        break;
        
      case USB_REQ_SET_ADDRESS:                      
        USBD_SetAddress(pdev, req);
        break;
        
      case USB_REQ_SET_CONFIGURATION:                    
        USBD_SetConfig (pdev , req);
        break;
        
      case USB_REQ_GET_CONFIGURATION:                 
        USBD_GetConfig (pdev , req);
        break;
        
      case USB_REQ_GET_STATUS:                                  
        USBD_GetStatus (pdev , req);
        break;
        
        
      case USB_REQ_SET_FEATURE:   
        USBD_SetFeature (pdev , req);    
        break;
        
      case USB_REQ_CLEAR_FEATURE:                                   
        USBD_ClrFeature (pdev , req);
        break;
        
      default:  
        USBD_CtlError(pdev , req);
        break;
      }
      
      return ret;
    }
    
    /**
    * @brief  USBD_StdItfReq
    *         Handle standard usb interface requests
    * @param  pdev: USB OTG device instance
    * @param  req: usb request
    * @retval status
    */
    USBD_Status  USBD_StdItfReq (USB_OTG_CORE_HANDLE  *pdev, USB_SETUP_REQ  *req)
    {
      USBD_Status ret = USBD_OK; 
      
      switch (pdev->dev.device_status) 
      {
      case USB_OTG_CONFIGURED:
        
        if (LOBYTE(req->wIndex) <= USBD_ITF_MAX_NUM) 
        {
          pdev->dev.class_cb->Setup (pdev, req); 
          
          if((req->wLength == 0)&& (ret == USBD_OK))
          {
             USBD_CtlSendStatus(pdev);
          }
        } 
        else 
        {                                               
           USBD_CtlError(pdev , req);
        }
        break;
        
      default:
         USBD_CtlError(pdev , req);
        break;
      }
      return ret;
    }
    
    /**
    * @brief  USBD_StdEPReq
    *         Handle standard usb endpoint requests
    * @param  pdev: USB OTG device instance
    * @param  req: usb request
    * @retval status
    */
    USBD_Status  USBD_StdEPReq (USB_OTG_CORE_HANDLE  *pdev, USB_SETUP_REQ  *req)
    {
      
      uint8_t   ep_addr;
      USBD_Status ret = USBD_OK; 
      
      ep_addr  = LOBYTE(req->wIndex);   
      
      switch (req->bRequest) 
      {
        
      case USB_REQ_SET_FEATURE :
        
        switch (pdev->dev.device_status) 
        {
        case USB_OTG_ADDRESSED:          
          if ((ep_addr != 0x00) && (ep_addr != 0x80)) 
          {
            DCD_EP_Stall(pdev , ep_addr);
          }
          break;	
          
        case USB_OTG_CONFIGURED:   
          if (req->wValue == USB_FEATURE_EP_HALT)
          {
            if ((ep_addr != 0x00) && (ep_addr != 0x80)) 
            { 
              DCD_EP_Stall(pdev , ep_addr);
              
            }
          }
          pdev->dev.class_cb->Setup (pdev, req);   
          USBD_CtlSendStatus(pdev);
          
          break;
          
        default:                         
          USBD_CtlError(pdev , req);
          break;    
        }
        break;
        
      case USB_REQ_CLEAR_FEATURE :
        
        switch (pdev->dev.device_status) 
        {
        case USB_OTG_ADDRESSED:          
          if ((ep_addr != 0x00) && (ep_addr != 0x80)) 
          {
            DCD_EP_Stall(pdev , ep_addr);
          }
          break;	
          
        case USB_OTG_CONFIGURED:   
          if (req->wValue == USB_FEATURE_EP_HALT)
          {
            if ((ep_addr != 0x00) && (ep_addr != 0x80)) 
            {        
              DCD_EP_ClrStall(pdev , ep_addr);
              pdev->dev.class_cb->Setup (pdev, req);
            }
            USBD_CtlSendStatus(pdev);
          }
          break;
          
        default:                         
           USBD_CtlError(pdev , req);
          break;    
        }
        break;
        
      case USB_REQ_GET_STATUS:                  
        switch (pdev->dev.device_status) 
        {
        case USB_OTG_ADDRESSED:          
          if ((ep_addr != 0x00) && (ep_addr != 0x80)) 
          {
            DCD_EP_Stall(pdev , ep_addr);
          }
          break;	
          
        case USB_OTG_CONFIGURED:         
          
          
          if ((ep_addr & 0x80)== 0x80)
          {
            if(pdev->dev.in_ep[ep_addr & 0x7F].is_stall)
            {
              USBD_ep_status = 0x0001;     
            }
            else
            {
              USBD_ep_status = 0x0000;  
            }
          }
          else if ((ep_addr & 0x80)== 0x00)
          {
            if(pdev->dev.out_ep[ep_addr].is_stall)
            {
              USBD_ep_status = 0x0001;     
            }
            
            else 
            {
              USBD_ep_status = 0x0000;     
            }      
          }
          USBD_CtlSendData (pdev,
                            (uint8_t *)&USBD_ep_status,
                            2);
          break;
          
        default:                         
           USBD_CtlError(pdev , req);
          break;
        }
        break;
        
      default:
        break;
      }
      return ret;
    }
    /**
    * @brief  USBD_GetDescriptor
    *         Handle Get Descriptor requests
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_GetDescriptor(USB_OTG_CORE_HANDLE  *pdev, 
                                   USB_SETUP_REQ *req)
    {
      uint16_t len;
      uint8_t *pbuf;
      
        
      switch (req->wValue >> 8)
      {
      case USB_DESC_TYPE_DEVICE:
        pbuf = pdev->dev.usr_device->GetDeviceDescriptor(pdev->cfg.speed, &len);
        if ((req->wLength == 64) ||( pdev->dev.device_status == USB_OTG_DEFAULT))  
        {                  
          len = 8;
        }
        break;
        
      case USB_DESC_TYPE_CONFIGURATION:
          pbuf   = (uint8_t *)pdev->dev.class_cb->GetConfigDescriptor(pdev->cfg.speed, &len);
    #ifdef USB_OTG_HS_CORE
        if((pdev->cfg.speed == USB_OTG_SPEED_FULL )&&
           (pdev->cfg.phy_itface  == USB_OTG_ULPI_PHY))
        {
          pbuf   = (uint8_t *)pdev->dev.class_cb->GetOtherConfigDescriptor(pdev->cfg.speed, &len);
        }
    #endif  
        pbuf[1] = USB_DESC_TYPE_CONFIGURATION;
        pdev->dev.pConfig_descriptor = pbuf;    
        break;
        
      case USB_DESC_TYPE_STRING:
        switch ((uint8_t)(req->wValue))
        {
        case USBD_IDX_LANGID_STR:
         pbuf = pdev->dev.usr_device->GetLangIDStrDescriptor(pdev->cfg.speed, &len);        
          break;
          
        case USBD_IDX_MFC_STR:
          pbuf = pdev->dev.usr_device->GetManufacturerStrDescriptor(pdev->cfg.speed, &len);
          break;
          
        case USBD_IDX_PRODUCT_STR:
          pbuf = pdev->dev.usr_device->GetProductStrDescriptor(pdev->cfg.speed, &len);
          break;
          
        case USBD_IDX_SERIAL_STR:
          pbuf = pdev->dev.usr_device->GetSerialStrDescriptor(pdev->cfg.speed, &len);
          break;
          
        case USBD_IDX_CONFIG_STR:
          pbuf = pdev->dev.usr_device->GetConfigurationStrDescriptor(pdev->cfg.speed, &len);
          break;
          
        case USBD_IDX_INTERFACE_STR:
          pbuf = pdev->dev.usr_device->GetInterfaceStrDescriptor(pdev->cfg.speed, &len);
          break;
          
        default:
    #ifdef USB_SUPPORT_USER_STRING_DESC
          pbuf = pdev->dev.class_cb->GetUsrStrDescriptor(pdev->cfg.speed, (req->wValue) , &len);
          break;
    #else      
           USBD_CtlError(pdev , req);
          return;
    #endif /* USBD_CtlError(pdev , req); */      
        }
        break;
      case USB_DESC_TYPE_DEVICE_QUALIFIER:                   
    #ifdef USB_OTG_HS_CORE
        if(pdev->cfg.speed == USB_OTG_SPEED_HIGH  )   
        {
          
          pbuf   = (uint8_t *)pdev->dev.class_cb->GetConfigDescriptor(pdev->cfg.speed, &len);
                
          USBD_DeviceQualifierDesc[4]= pbuf[14];
          USBD_DeviceQualifierDesc[5]= pbuf[15];
          USBD_DeviceQualifierDesc[6]= pbuf[16];
          
          pbuf = USBD_DeviceQualifierDesc;
          len  = USB_LEN_DEV_QUALIFIER_DESC;
          break;
        }
        else
        {
          USBD_CtlError(pdev , req);
          return;
        }
    #else
          USBD_CtlError(pdev , req);
          return;
    #endif    
    
      case USB_DESC_TYPE_OTHER_SPEED_CONFIGURATION:
    #ifdef USB_OTG_HS_CORE   
    
        if(pdev->cfg.speed == USB_OTG_SPEED_HIGH  )   
        {
          pbuf   = (uint8_t *)pdev->dev.class_cb->GetOtherConfigDescriptor(pdev->cfg.speed, &len);
          pbuf[1] = USB_DESC_TYPE_OTHER_SPEED_CONFIGURATION;
          break; 
        }
        else
        {
          USBD_CtlError(pdev , req);
          return;
        }
    #else
          USBD_CtlError(pdev , req);
          return;
    #endif     
    
        
      default: 
         USBD_CtlError(pdev , req);
        return;
      }
      
      if((len != 0)&& (req->wLength != 0))
      {
        
        len = MIN(len , req->wLength);
        
        USBD_CtlSendData (pdev, 
                          pbuf,
                          len);
      }
      
    }
    
    /**
    * @brief  USBD_SetAddress
    *         Set device address
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_SetAddress(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req)
    {
      uint8_t  dev_addr; 
      
      if ((req->wIndex == 0) && (req->wLength == 0)) 
      {
        dev_addr = (uint8_t)(req->wValue) & 0x7F;     
        
        if (pdev->dev.device_status == USB_OTG_CONFIGURED) 
        {
          USBD_CtlError(pdev , req);
        } 
        else 
        {
          pdev->dev.device_address = dev_addr;
          DCD_EP_SetAddress(pdev, dev_addr);               
          USBD_CtlSendStatus(pdev);                         
          
          if (dev_addr != 0) 
          {
            pdev->dev.device_status  = USB_OTG_ADDRESSED;
          } 
          else 
          {
            pdev->dev.device_status  = USB_OTG_DEFAULT; 
          }
        }
      } 
      else 
      {
         USBD_CtlError(pdev , req);                        
      } 
    }
    
    /**
    * @brief  USBD_SetConfig
    *         Handle Set device configuration request
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_SetConfig(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req)
    {
      
      static uint8_t  cfgidx;
      
      cfgidx = (uint8_t)(req->wValue);                 
      
      if (cfgidx > USBD_CFG_MAX_NUM ) 
      {            
         USBD_CtlError(pdev , req);                              
      } 
      else 
      {
        switch (pdev->dev.device_status) 
        {
        case USB_OTG_ADDRESSED:
          if (cfgidx) 
          {                                			   							   							   				
            pdev->dev.device_config = cfgidx;
            pdev->dev.device_status = USB_OTG_CONFIGURED;
            USBD_SetCfg(pdev , cfgidx);
            USBD_CtlSendStatus(pdev);
          }
          else 
          {
             USBD_CtlSendStatus(pdev);
          }
          break;
          
        case USB_OTG_CONFIGURED:
          if (cfgidx == 0) 
          {                           
            pdev->dev.device_status = USB_OTG_ADDRESSED;
            pdev->dev.device_config = cfgidx;          
            USBD_ClrCfg(pdev , cfgidx);
            USBD_CtlSendStatus(pdev);
            
          } 
          else  if (cfgidx != pdev->dev.device_config) 
          {
            /* Clear old configuration */
            USBD_ClrCfg(pdev , pdev->dev.device_config);
            
            /* set new configuration */
            pdev->dev.device_config = cfgidx;
            USBD_SetCfg(pdev , cfgidx);
            USBD_CtlSendStatus(pdev);
          }
          else
          {
            USBD_CtlSendStatus(pdev);
          }
          break;
          
        default:					
           USBD_CtlError(pdev , req);                     
          break;
        }
      }
    }
    
    /**
    * @brief  USBD_GetConfig
    *         Handle Get device configuration request
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_GetConfig(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req)
    {
     
      if (req->wLength != 1) 
      {                   
         USBD_CtlError(pdev , req);
      }
      else 
      {
        switch (pdev->dev.device_status )  
        {
        case USB_OTG_ADDRESSED:                     
          
          USBD_CtlSendData (pdev, 
                            (uint8_t *)&USBD_default_cfg,
                            1);
          break;
          
        case USB_OTG_CONFIGURED:                   
          
          USBD_CtlSendData (pdev, 
                            &pdev->dev.device_config,
                            1);
          break;
          
        default:
           USBD_CtlError(pdev , req);
          break;
        }
      }
    }
    
    /**
    * @brief  USBD_GetStatus
    *         Handle Get Status request
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_GetStatus(USB_OTG_CORE_HANDLE  *pdev, 
                               USB_SETUP_REQ *req)
    {
      
        
      switch (pdev->dev.device_status) 
      {
      case USB_OTG_ADDRESSED:
      case USB_OTG_CONFIGURED:
        
    #ifdef USBD_SELF_POWERED
        USBD_cfg_status = USB_CONFIG_SELF_POWERED;                                    
    #else
        USBD_cfg_status = 0x00;                                    
    #endif
                          
        if (pdev->dev.DevRemoteWakeup) 
        {
          USBD_cfg_status |= USB_CONFIG_REMOTE_WAKEUP;                                
        }
        
        USBD_CtlSendData (pdev, 
                          (uint8_t *)&USBD_cfg_status,
                          2);
        break;
        
      default :
        USBD_CtlError(pdev , req);                        
        break;
      }
    }
    
    
    /**
    * @brief  USBD_SetFeature
    *         Handle Set device feature request
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_SetFeature(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req)
    {
    
      USB_OTG_DCTL_TypeDef     dctl;
      uint8_t test_mode = 0;
     
      if (req->wValue == USB_FEATURE_REMOTE_WAKEUP)
      {
        pdev->dev.DevRemoteWakeup = 1;  
        pdev->dev.class_cb->Setup (pdev, req);   
        USBD_CtlSendStatus(pdev);
      }
    
      else if ((req->wValue == USB_FEATURE_TEST_MODE) && 
               ((req->wIndex & 0xFF) == 0))
      {
        dctl.d32 = USB_OTG_READ_REG32(&pdev->regs.DREGS->DCTL);
        
        test_mode = req->wIndex >> 8;
        switch (test_mode) 
        {
        case 1: // TEST_J
          dctl.b.tstctl = 1;
          break;
          
        case 2: // TEST_K	
          dctl.b.tstctl = 2;
          break;
          
        case 3: // TEST_SE0_NAK
          dctl.b.tstctl = 3;
          break;
          
        case 4: // TEST_PACKET
          dctl.b.tstctl = 4;
          break;
          
        case 5: // TEST_FORCE_ENABLE
          dctl.b.tstctl = 5;
          break;
        }
        SET_TEST_MODE = dctl;
        pdev->dev.test_mode = 1;
        USBD_CtlSendStatus(pdev);
      }
    
    }
    
    
    /**
    * @brief  USBD_ClrFeature
    *         Handle clear device feature request
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval status
    */
    static void USBD_ClrFeature(USB_OTG_CORE_HANDLE  *pdev, 
                                USB_SETUP_REQ *req)
    {
      switch (pdev->dev.device_status)
      {
      case USB_OTG_ADDRESSED:
      case USB_OTG_CONFIGURED:
        if (req->wValue == USB_FEATURE_REMOTE_WAKEUP) 
        {
          pdev->dev.DevRemoteWakeup = 0; 
          pdev->dev.class_cb->Setup (pdev, req);   
          USBD_CtlSendStatus(pdev);
        }
        break;
        
      default :
         USBD_CtlError(pdev , req);
        break;
      }
    }
    
    /**
    * @brief  USBD_ParseSetupRequest 
    *         Copy buffer into setup structure
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval None
    */
    
    void USBD_ParseSetupRequest( USB_OTG_CORE_HANDLE  *pdev,
                                USB_SETUP_REQ *req)
    {
      req->bmRequest     = *(uint8_t *)  (pdev->dev.setup_packet);
      req->bRequest      = *(uint8_t *)  (pdev->dev.setup_packet +  1);
      req->wValue        = SWAPBYTE      (pdev->dev.setup_packet +  2);
      req->wIndex        = SWAPBYTE      (pdev->dev.setup_packet +  4);
      req->wLength       = SWAPBYTE      (pdev->dev.setup_packet +  6);
      
      pdev->dev.in_ep[0].ctl_data_len = req->wLength  ;
      pdev->dev.device_state = USB_OTG_EP0_SETUP;
    }
    
    /**
    * @brief  USBD_CtlError 
    *         Handle USB low level Error
    * @param  pdev: device instance
    * @param  req: usb request
    * @retval None
    */
    
    void USBD_CtlError( USB_OTG_CORE_HANDLE  *pdev,
                                USB_SETUP_REQ *req)
    {
      
      DCD_EP_Stall(pdev , 0x80);
      DCD_EP_Stall(pdev , 0);
      USB_OTG_EP0_OutStart(pdev);  
    }
    
    
    /**
      * @brief  USBD_GetString
      *         Convert Ascii string into unicode one
      * @param  desc : descriptor buffer
      * @param  unicode : Formatted string buffer (unicode)
      * @param  len : descriptor length
      * @retval None
      */
    void USBD_GetString(const char *desc, uint8_t *unicode, uint16_t *len)
    {
      uint8_t idx = 0;
      
      if (desc != NULL) 
      {
        *len =  USBD_GetLen(desc) * 2 + 2;    
        unicode[idx++] = *len;
        unicode[idx++] =  USB_DESC_TYPE_STRING;
        
        while (*desc != NULL) 
        {
          unicode[idx++] = *desc++;
          unicode[idx++] =  0x00;
        }
      } 
    }
    
    /**
      * @brief  USBD_GetLen
      *         return the string length
       * @param  buf : pointer to the ascii string buffer
      * @retval string length
      */
    static uint8_t USBD_GetLen(const char *buf)
    {
        uint8_t  len = 0;
    
        while (*buf != NULL) 
        {
            len++;
            buf++;
        }
    
        return len;
    }
    /**
      * @}
      */ 
    
    
    /**
      * @}
      */ 
    
    
    /**
      * @}
      */ 
    
    /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/