STM32 之四标准外设版 USB 驱动 + MSC(Host) + Fatfs 移植

小灰灰 2022-06-02 02:52 471阅读 0赞

## 写在前面 ##

*  现在，网上关于STM32的USB的文章数不胜数。写这篇文章仅仅是对于自我学习的一个记录。主要是对实际学习中遇到的一些棘手问题做个备忘录。***使用的芯片为STM32F407VG*** 。
 *  目前，ST的USB驱动有两套，一套是早期的独立版USB驱动，官方培训文档中称为**Legacy library**，最新版为2.2.0；一套为针对其Cube系列的驱动，根据芯片不同可能有区别，具体见对应芯片的Cube驱动包，官方培训文档中称为**Cube library**。 本文使用的为Legacy libraryUSB驱动。更详细的请参考博文[STM32 之 USB IP（USB模块） 详解][STM32 _ USB IP_USB_]。
 *  HAL库 + Legacy library USB库两个混用
 *  目前，[Fatfs ][Fatfs]驱动最新版为R0.13a 。
 *  本文多出自于ST的官方文档，读者也可以直接去ST官网查阅相关文档。
 *  本文主要涉及USB Host（全速）+ MSC + Fatfs的移植。其他移植后续用到再说。
 *  关于独立版USB驱动库的详解见 http://blog.csdn.net/zcshoucsdn/article/details/78936456

## USB驱动部分 ##

### 源码移植 ###

源码的移植相对来说比较简单，使用时，根据需要复制相关的文件即可。需要注意的是，整理一下源码的结构。这个在上一篇博文中已经由说明了。具体见下图：  
![USB Host][]  
  在移植其他部分的时候与之类似，只需要替换成对应部分的源码文件即可。

> 1.  源码中的 USB OTG部分是所有其他模块的驱动程序。
> 2.  `usbh_msc_fatfs.c`为ST提供的FatFs的`diskio.c`的具体实现文件。在使用了该文件后，用户不必再自行实现FafFs的`diskio.c`了。

\#\#\#源码配置  
  整个USB驱动用于灵活的配置选项，且通过一个配置文件的形式给出。这样，使用者可以尽量少的修改的驱动源代码。这些配置文件均为用户级别的文件，通常来说置于用户代码目录下。如下如所示：  
![USBHostUser][]  
  作为用户级文件，通常所有的用户代码均在以上文件做修改即可，只有少数特殊处理会设计到驱动程序源码的修改。在配置好后，一般来说，所有修改均在`usbh_usr.h/.c`中。

#### usb\_config.h ####

`usb_config.h`是USB OTG 底层驱动的配置文件。在USB OTG的源代码中，ST提供了`usb_conf_template.h`。使用者只需要复制该文件到自己的代码目录下，修改即可。具体配置见下文的注释部分：

/** ****************************************************************************** * @file usb_conf.h * @author * @version V2.2.0 * @date 2017.12.27 * @brief USB的底层驱动配置 ****************************************************************************** * @attention * * <h2><center>© COPYRIGHT 2017 ST</center></h2> * * ****************************************************************************** */
    /* Define to prevent recursive inclusion -------------------------------------*/
    #ifndef __USB_CONF__H__
    #define __USB_CONF__H__
    
    /* Includes ------------------------------------------------------------------*/
    #include "stm32f4xx.h" /* 这里需要包含自己使用的ST的库的头文件 */
    /** @addtogroup USB_OTG_DRIVER * @{ */
    /** @defgroup USB_CONF * @brief USB 底层驱动配置文件 * @{ */ 
    /** @defgroup USB_CONF_Exported_Defines * @{ */ 
    /* USB Core and PHY interface 配置. Tip: To avoid modifying these defines each time you need to change the USB configuration, you can declare the needed define in your toolchain compiler preprocessor. */
    /**** 配置文件包含了Full Speed 和 High Speed 两种速率的配置，使用时，从两者选择其一即可。****/
    /****************** USB OTG FS PHY 配置 ******************************* * USB OTG FS Core 支持 one on-chip Full Speed PHY。通常，ST芯片内部已经集成了该PHY。 * * 当使用了FS core时，宏USE_EMBEDDED_PHY 需要在编译器中定义. * *******************************************************************************/
    #ifndef USE_USB_OTG_FS
    	#define USE_USB_OTG_FS /* 使用 FS， 与下面的 HS 只能选一个。目前，终端只支持FS */
    #endif /* USE_USB_OTG_FS */
    
    #ifdef USE_USB_OTG_FS 
    	#define USB_OTG_FS_CORE
    #endif
    /****************** USB OTG HS PHY 配置 ******************************* * USB OTG HS Core 支持 两种 PHY 接口: * (i) 使用外部高速PHY的ULPI 接口: USB HS Core 工作在高速模式下 * (ii) 片内Full Speed PHY: USB HS Core 工作在全速模式下 * 通过下面两个宏，选择使用哪种PHY: * (i) USE_ULPI_PHY: if the USB OTG HS Core is to be used in High speed mode * (ii) USE_EMBEDDED_PHY: if the USB OTG HS Core is to be used in Full speed mode * * Notes: * - The USE_ULPI_PHY symbol is defined in the project compiler preprocessor as default PHY when HS core is used. * - On STM322xG-EVAL and STM324xG-EVAL boards, only configuration(i) is available. * Configuration (ii) need a different hardware, for more details refer to your STM32 device datasheet. *******************************************************************************/
    #ifndef USE_USB_OTG_HS
    	//#define USE_USB_OTG_HS
    #endif /* USE_USB_OTG_HS */
    
    #ifndef USE_ULPI_PHY
    	//#define USE_ULPI_PHY
    #endif /* USE_ULPI_PHY */
    
    #ifndef USE_EMBEDDED_PHY
    	//#define USE_EMBEDDED_PHY
    #endif /* USE_EMBEDDED_PHY */
    
    #ifdef USE_USB_OTG_HS 
    	#define USB_OTG_HS_CORE
    #endif
    
    /******************************************************************************* * FIFO Size Configuration in Device mode * * (i) Receive data FIFO size = RAM for setup packets + * OUT endpoint control information + * data OUT packets + miscellaneous * Space = ONE 32-bits words * --> RAM for setup packets = 10 spaces * (n is the nbr of CTRL EPs the device core supports) * --> OUT EP CTRL info = 1 space * (one space for status information written to the FIFO along with each * received packet) * --> data OUT packets = (Largest Packet Size / 4) + 1 spaces * (MINIMUM to receive packets) * --> OR data OUT packets = at least 2*(Largest Packet Size / 4) + 1 spaces * (if high-bandwidth EP is enabled or multiple isochronous EPs) * --> miscellaneous = 1 space per OUT EP * (one space for transfer complete status information also pushed to the * FIFO with each endpoint's last packet) * * (ii)MINIMUM RAM space required for each IN EP Tx FIFO = MAX packet size for * that particular IN EP. More space allocated in the IN EP Tx FIFO results * in a better performance on the USB and can hide latencies on the AHB. * * (iii) TXn min size = 16 words. (n : Transmit FIFO index) * (iv) When a TxFIFO is not used, the Configuration should be as follows: * case 1 : n > m and Txn is not used (n,m : Transmit FIFO indexes) * --> Txm can use the space allocated for Txn. * case2 : n < m and Txn is not used (n,m : Transmit FIFO indexes) * --> Txn should be configured with the minimum space of 16 words * (v) The FIFO is used optimally when used TxFIFOs are allocated in the top * of the FIFO.Ex: use EP1 and EP2 as IN instead of EP1 and EP3 as IN ones. *******************************************************************************/
    
    /******************************************************************************* * FIFO Size Configuration in Host mode * * (i) Receive data FIFO size = (Largest Packet Size / 4) + 1 or * 2x (Largest Packet Size / 4) + 1, If a * high-bandwidth channel or multiple isochronous * channels are enabled * * (ii) For the host nonperiodic Transmit FIFO is the largest maximum packet size * for all supported nonperiodic OUT channels. Typically, a space * corresponding to two Largest Packet Size is recommended. * * (iii) The minimum amount of RAM required for Host periodic Transmit FIFO is * the largest maximum packet size for all supported periodic OUT channels. * If there is at least one High Bandwidth Isochronous OUT endpoint, * then the space must be at least two times the maximum packet size for * that channel. *******************************************************************************/
     
    /****************** USB OTG HS CONFIGURATION **********************************/
    /* 以下暂不使用 */
    #ifdef USB_OTG_HS_CORE
    	#define RX_FIFO_HS_SIZE 512 /* 设置高速内核的接收FIFO大小。*/
    	/* 设置设备端点的发送FIFO大小（高速），其中0~3是要使用的端点的索引。*/
    	#define TX0_FIFO_HS_SIZE 512
    	#define TX1_FIFO_HS_SIZE 512
    	#define TX2_FIFO_HS_SIZE 0
    	#define TX3_FIFO_HS_SIZE 0
    	#define TX4_FIFO_HS_SIZE 0
    	#define TX5_FIFO_HS_SIZE 0
    	#define TXH_NP_HS_FIFOSIZ 96 /* 设置主机模式（高速）的非周期性发送FIFO大小。 */
    	#define TXH_P_HS_FIFOSIZ 96 /* 设置主机模式（高速）的周期性发送FIFO大小。*/
    
    // #define USB_OTG_HS_LOW_PWR_MGMT_SUPPORT /* 实现高速核心（USB核心时钟门控等）的低功耗管理。 */
    // #define USB_OTG_HS_SOF_OUTPUT_ENABLED
    
    // #define USB_OTG_INTERNAL_VBUS_ENABLED
    	#define USB_OTG_EXTERNAL_VBUS_ENABLED
    
    	#ifdef USE_ULPI_PHY
    		#define USB_OTG_ULPI_PHY_ENABLED /* 启用高速内核的ULPI PHY。 */
    	#endif
    	#ifdef USE_EMBEDDED_PHY
    		#define USB_OTG_EMBEDDED_PHY_ENABLED /* 为高速内核启用嵌入式FS PHY。 */
    	#endif
    	#define USB_OTG_HS_INTERNAL_DMA_ENABLED /* 启用高速内核的内部DMA功能。 */
    	#define USB_OTG_HS_DEDICATED_EP1_ENABLED /* 在高速内核中为器件模式启用专用的端点1功能。 */
    #endif
    
    /****************** USB OTG FS CONFIGURATION **********************************/
    #ifdef USB_OTG_FS_CORE
    	#define RX_FIFO_FS_SIZE 128 /* 设置全速内核的接收FIFO大小。 */
    	/* 设置设备端点的发送FIFO大小（全速），其中0~3是要使用的端点的索引。*/
    	#define TX0_FIFO_FS_SIZE 64 
    	#define TX1_FIFO_FS_SIZE 128
    	#define TX2_FIFO_FS_SIZE 0
    	#define TX3_FIFO_FS_SIZE 0
    	#define TXH_NP_FS_FIFOSIZ 96 /* 设置主机模式（全速）的非周期性发送FIFO大小。 */
    	#define TXH_P_FS_FIFOSIZ 96 /* 设置主机模式（全速）的周期性发送FIFO大小。*/
    
    // #define USB_OTG_FS_LOW_PWR_MGMT_SUPPORT /* 实现全速核心（USB核心时钟门控等）的低功耗管理。 */
    // #define USB_OTG_FS_SOF_OUTPUT_ENABLED
    #endif
    
    /****************** USB OTG MISC CONFIGURATION ********************************/
    //#define VBUS_SENSING_ENABLED
    
    /****************** USB OTG MODE CONFIGURATION ********************************/
    #define USE_HOST_MODE /* 采用 Host 模式 与下面的 USE_DEVICE_MODE 和 USE_OTG_MODE 任选其一 */
    //#define USE_DEVICE_MODE
    //#define USE_OTG_MODE
    
    #ifndef USB_OTG_FS_CORE
    	#ifndef USB_OTG_HS_CORE
    		#error "USB_OTG_HS_CORE or USB_OTG_FS_CORE should be defined"
    	#endif
    #endif
    
    #ifndef USE_DEVICE_MODE
    	#ifndef USE_HOST_MODE
    		#error "USE_DEVICE_MODE or USE_HOST_MODE should be defined"
    	#endif
    #endif
    
    #ifndef USE_USB_OTG_HS
    	#ifndef USE_USB_OTG_FS
    		#error "USE_USB_OTG_HS or USE_USB_OTG_FS should be defined"
    	#endif
    #else //USE_USB_OTG_HS
    	#ifndef USE_ULPI_PHY
    		#ifndef USE_EMBEDDED_PHY
    			 #error "USE_ULPI_PHY or USE_EMBEDDED_PHY should be defined"
    		#endif
    	#endif
    #endif
    
    /****************** C Compilers dependant keywords ****************************/
    /* In HS mode and when the DMA is used, all variables and data structures dealing with the DMA during the transaction process should be 4-bytes aligned */    
    #ifdef USB_OTG_HS_INTERNAL_DMA_ENABLED
      #if defined (__GNUC__) /* GNU Compiler */
        #define __ALIGN_END __attribute__ ((aligned (4)))
        #define __ALIGN_BEGIN 
      #else 
        #define __ALIGN_END
        #if defined (__CC_ARM) /* ARM Compiler */
          #define __ALIGN_BEGIN __align(4) 
        #elif defined (__ICCARM__) /* IAR Compiler */
          #define __ALIGN_BEGIN 
        #elif defined (__TASKING__) /* TASKING Compiler */
          #define __ALIGN_BEGIN __align(4) 
        #endif /* __CC_ARM */  
      #endif /* __GNUC__ */ 
    #else
      #define __ALIGN_BEGIN
      #define __ALIGN_END 
    #endif /* USB_OTG_HS_INTERNAL_DMA_ENABLED */
    
    /* __packed keyword used to decrease the data type alignment to 1-byte */
    #if defined (__CC_ARM) /* ARM Compiler */
      #define __packed __packed
    #elif defined (__ICCARM__) /* IAR Compiler */
      #define __packed __packed
    #elif defined ( __GNUC__ ) /* GNU Compiler */                        
      #define __packed __attribute__ ((__packed__))
    #elif defined (__TASKING__) /* TASKING Compiler */
      #define __packed __unaligned
    #endif /* __CC_ARM */
    
    /** * @} */ 
      /*省略*/
    #endif //__USB_CONF__H__
    /** * @} */ 
    /** * @} */ 
    /************************ (C) COPYRIGHT *****END OF FILE****/

#### usbh\_config.h ####

`usbh_config.h`是USB Host 底层驱动的配置文件。在USB OTG的源代码中，ST提供了`usbh_conf_template.h`。使用者只需要复制该文件到自己的代码目录下，修改即可。具体配置见下文的注释部分：

/** ****************************************************************************** * @file usbh_conf.h * @author * @version V2.2.0 * @date 2017.12.27 * @brief USB Host library 配置 ****************************************************************************** * @attention * * <h2><center>© COPYRIGHT 2017 </center></h2> * ****************************************************************************** */
    /* Define to prevent recursive inclusion -------------------------------------*/
    #ifndef __USBH_CONF__H__
    #define __USBH_CONF__H__
    /* Includes ------------------------------------------------------------------*/
    // #include "xxx.h" /* 包含自己的各种头文件*/
    /** @addtogroup USBH_OTG_DRIVER * @{ */
    /** @defgroup USBH_CONF * @brief USB Host 底层驱动配置文件 * @{ */
    /** @defgroup USBH_CONF_Exported_Defines * @{ */
    #define USBH_MAX_NUM_ENDPOINTS 2 /* 支持端点的最大数量 1 bulk IN + 1 bulk Out */
    #define USBH_MAX_NUM_INTERFACES 2 /* 支持接口的最大数量 */
    
    #ifdef USE_USB_OTG_FS
    	#define USBH_MSC_MPS_SIZE 0x40
    #else
    	#define USBH_MSC_MPS_SIZE 0x200
    #endif
    #define USBH_MAX_DATA_BUFFER 0x400
    
    /* 错误信息打印函数 重定向 这里需要注意：该库使用了LCD_ErrLog，需要进行重定向，否则报错 */
    /* 感觉 库直接将 其改名为 USB_Log 或者 USB_ErrLog 最好了 */
    #define LCD_ErrLog(str) udwComSendData(COM_CONSOLE, str, strlen(str));
    
    /* 与 Fatfs 对接使用。必须定义为 1。在 FatFs 的配置文件中，有个配置项 FF_USE_TRIM。具体见该宏的说明。 */
    #define _USE_IOCTL 1
    /** * @} */
    /** @defgroup USBH_CONF_Exported_Types * @{ */
    /** * @} */
    /** @defgroup USBH_CONF_Exported_Macros * @{ */
    /** * @} */
    /** @defgroup USBH_CONF_Exported_Variables * @{ */
    /** * @} */
    /** @defgroup USBH_CONF_Exported_FunctionsPrototype * @{ */
    /** * @} */
    
    #endif //__USBH_CONF__H__
    
    /** * @} */
    /** * @} */
    /************************ (C) COPYRIGHT *****END OF FILE****/

`_USE_IOCTL` 这个宏需要特殊说明一下。这个宏值是 ST 的驱动添加的。其是与 FatFs 相关的。在 FatFs 中有个配置项 `FF_USE_TRIM`，这个宏如果被定义为 1，则 FatFs 要求必须在 `diskio.c` 中定义函数 `disk_ioctl()`。但是可能由于文件包含关系，导致 ST 在 USB 库中不能直接使用 `FF_USE_TRIM`。所以才添加了 `_USE_IOCTL` 。  
  更进一步，这个宏必须被定义为 1，因为在 FatFs 中存在一个 BUG：FatFs 并没有处理好对函数 `disk_ioctl()` 的使用，如下：

#if !FF_FS_READONLY
    /*-----------------------------------------------------------------------*/
    /* Synchronize filesystem and data on the storage */
    /*-----------------------------------------------------------------------*/
    
    static FRESULT sync_fs (	/* Returns FR_OK or FR_DISK_ERR */
    	FATFS* fs		/* Filesystem object */
    )
    { 
    	FRESULT res;
    
    
    	res = sync_window(fs);
    	if (res == FR_OK) { 
    		if (fs->fs_type == FS_FAT32 && fs->fsi_flag == 1) { 	/* FAT32: Update FSInfo sector if needed */
    			/* Create FSInfo structure */
    			mem_set(fs->win, 0, sizeof fs->win);
    			st_word(fs->win + BS_55AA, 0xAA55);
    			st_dword(fs->win + FSI_LeadSig, 0x41615252);
    			st_dword(fs->win + FSI_StrucSig, 0x61417272);
    			st_dword(fs->win + FSI_Free_Count, fs->free_clst);
    			st_dword(fs->win + FSI_Nxt_Free, fs->last_clst);
    			/* Write it into the FSInfo sector */
    			fs->winsect = fs->volbase + 1;
    			disk_write(fs->pdrv, fs->win, fs->winsect, 1);
    			fs->fsi_flag = 0;
    		}
    		/* Make sure that no pending write process in the lower layer */
    		if (disk_ioctl(fs->pdrv, CTRL_SYNC, 0) != RES_OK) res = FR_DISK_ERR;
    	}
    
    	return res;
    }
    
    #endif

上面总是会调用函数 `disk_ioctl()`，如果不定义 `_USE_IOCTL`为 1 则将导致函数未定义 。处理上面这个调用，其他地方都是有相应的宏来控制对于该函数的读取的。如下：  
![在这里插入图片描述][2020112511192552.png_pic_center]

#### usbh\_bsp.c ####

包含（在USB OTG低级驱动程序的usb\_bsp.h文件中声明）来初始化GPIO的核心，延时方法和中断启用/禁用的函数的实现。在USB OTG的源代码中，ST提供了`usb_bsp_template.c`。使用者只需要复制该文件到自己的代码目录下，修改即可。具体需要实现的函数在`usb_bsp.h`中已经定义好了，使用者不能更改接口名。见下文的注释部分：

void USB_OTG_BSP_Init (USB_OTG_CORE_HANDLE *pdev);    /* 该接口中 实现 USB Host 使用的各种 GPIO等*/
    void USB_OTG_BSP_uDelay (const uint32_t usec);		/* USB 使用的延时函数 */
    void USB_OTG_BSP_mDelay (const uint32_t msec);    /* USB 使用的延时函数 */
    void USB_OTG_BSP_EnableInterrupt (USB_OTG_CORE_HANDLE *pdev);    /* USB 使用的中断 */
    void USB_OTG_BSP_TimerIRQ (void);
    /* 以下主要是用于 高速模式下的配置，如VBUS的过流检测等 */
    #ifdef USE_HOST_MODE
    void USB_OTG_BSP_ConfigVBUS(USB_OTG_CORE_HANDLE *pdev);
    void USB_OTG_BSP_DriveVBUS(USB_OTG_CORE_HANDLE *pdev,uint8_t state);
    void USB_OTG_BSP_Resume(USB_OTG_CORE_HANDLE *pdev);
    void USB_OTG_BSP_Suspend(USB_OTG_CORE_HANDLE *pdev);
    #endif /* USE_HOST_MODE */

#### usbh\_usr.c/.h ####

包含（在USB库的usbh\_usr.h文件中声明）来处理来自用户层（事件消息）的库事件的函数实现。需要实现的函数接口（注意：以下是针对MSC的，其他如HID的用户接口是不同的）见下文：

void USBH_USR_Init(void);
    void USBH_USR_DeInit(void);
    void USBH_USR_DeviceAttached(void);
    void USBH_USR_ResetDevice(void);
    void USBH_USR_DeviceDisconnected (void);
    void USBH_USR_OverCurrentDetected (void);
    void USBH_USR_DeviceSpeedDetected(uint8_t DeviceSpeed); 
    void USBH_USR_Device_DescAvailable(void *);
    void USBH_USR_DeviceAddressAssigned(void);
    void USBH_USR_Configuration_DescAvailable(USBH_CfgDesc_TypeDef * cfgDesc,
                                              USBH_InterfaceDesc_TypeDef *itfDesc,
                                              USBH_EpDesc_TypeDef *epDesc);
    void USBH_USR_Manufacturer_String(void *);
    void USBH_USR_Product_String(void *);
    void USBH_USR_SerialNum_String(void *);
    void USBH_USR_EnumerationDone(void);
    USBH_USR_Status USBH_USR_UserInput(void);
    void USBH_USR_DeviceNotSupported(void);
    void USBH_USR_UnrecoveredError(void);
    int USBH_USR_MSC_Application(void);

对于MSC，使用以下回调：`USBH_USR_MSC_Application()`。 在类初始化结束之后，这个函数被MSC状态机调用，以便向用户提供文件系统访问操作。使用者最终需要在该函数中实现自己的用户代码。在此回调中，用户可以使用FAT FS文件系统API实现对FAT文件系统的任何访问（文件打开，文件读取，文件写入…）。 用户还可以访问从库MSC类驱动程序导出的结构变量：USBH\_MSC\_Param。  
  其他接口是这个USB Host 状态机一步一步执行过程的函数。使用者可以在不同的步骤添加对应的处理。最终，使用类型`USBH_Usr_cb_TypeDef`，将所有函数注册进USB Host驱动。

/* USB Host 用户接口 类型定义 */
    typedef struct _USBH_USR_PROP
    { 
      void (*Init)(void);       /* HostLibInitialized */
      void (*DeInit)(void);       /* HostLibInitialized */  
      void (*DeviceAttached)(void);           /* DeviceAttached */
      void (*ResetDevice)(void);
      void (*DeviceDisconnected)(void); 
      void (*OverCurrentDetected)(void);  
      void (*DeviceSpeedDetected)(uint8_t DeviceSpeed);          /* DeviceSpeed */
      void (*DeviceDescAvailable)(void *);    /* DeviceDescriptor is available */
      void (*DeviceAddressAssigned)(void);  /* Address is assigned to USB Device */
      void (*ConfigurationDescAvailable)(USBH_CfgDesc_TypeDef *,
                                         USBH_InterfaceDesc_TypeDef *,
                                         USBH_EpDesc_TypeDef *); 
      /* Configuration Descriptor available */
      void (*ManufacturerString)(void *);     /* ManufacturerString*/
      void (*ProductString)(void *);          /* ProductString*/
      void (*SerialNumString)(void *);        /* SerialNubString*/
      void (*EnumerationDone)(void);           /* Enumeration finished */
      USBH_USR_Status (*UserInput)(void);
      int  (*UserApplication) (void);
      void (*DeviceNotSupported)(void); /* Device is not supported*/
      void (*UnrecoveredError)(void);
    
    }
    USBH_Usr_cb_TypeDef;
    /* USB Host 用户接口 使用示例 */
    USBH_Usr_cb_TypeDef USR_cb =
    { 
    	USBH_USR_Init,
    	USBH_USR_DeInit,
    	USBH_USR_DeviceAttached,
    	USBH_USR_ResetDevice,
    	USBH_USR_DeviceDisconnected,
    	USBH_USR_OverCurrentDetected,
    	USBH_USR_DeviceSpeedDetected,
    	USBH_USR_Device_DescAvailable,
    	USBH_USR_DeviceAddressAssigned,
    	USBH_USR_Configuration_DescAvailable,
    	USBH_USR_Manufacturer_String,
    	USBH_USR_Product_String,
    	USBH_USR_SerialNum_String,
    	USBH_USR_EnumerationDone,
    	USBH_USR_UserInput,
    	USBH_USR_MSC_Application,
    	USBH_USR_DeviceNotSupported,
    	USBH_USR_UnrecoveredError
    };

### 注意事项 ###

*  一旦使用了DMA( 高速模式下)，所有结构体必须是四字节对齐的。
 *  如下即可使用 USB Host

/* 定义 USB_OTG_Core */
    #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 USB_OTG_CORE_HANDLE      USB_OTG_Core __ALIGN_END;
    /* 定义 USB_Host */
    #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 USBH_HOST                USB_Host __ALIGN_END;
    
    /****注意：在非启用到了DMA的高速模式下， 以上两个定义可直接简化（不需要对齐处理）如下： * USB_OTG_CORE_HANDLE USB_OTG_Core; * USBH_HOST USB_Host; ****/
    
    /* 初始化 USB Host 库 */
    USBH_Init( &USB_OTG_Core, 
    #ifdef USE_USB_OTG_FS 
    	USB_OTG_FS_CORE_ID,
    #else 
    	USB_OTG_HS_CORE_ID,
    #endif 
    	&USB_Host,
    	&USBH_MSC_cb, 
    	&USR_cb );
    
    /* 最后，周期调用以下函数即可 */
    USBH_Process(&USB_OTG_Core, &USB_Host);

*  还需要在中断处理文件中，添加以下中断（如果使用了其他功能的终端，自行添加）：

/** * @brief OTG_FS_IRQHandler * This function handles USB-On-The-Go FS global interrupt request. * requests. * @param None * @retval None */
    #ifdef USE_USB_OTG_FS 
    void OTG_FS_IRQHandler(void)
    #else
    void OTG_HS_IRQHandler(void)
    #endif
    { 
    	USBH_OTG_ISR_Handler(&USB_OTG_Core);
    }

## Fatfs部分 ##

### 源码移植 ###

目前，FatFS的最新版为R0.13a。从R0.13开始，作者将配置宏统一为可FF\_开头。目前网上多数文章都是针对之前的，许多配置名与最新新版的源码是对不上。  
![FatfsFolder][]  
  使用FatFs最简单的只需要关系两个文件即可：`ff.c/h`和`diskio.c/h`。其中，`diskio.c/h`是一个模板，用户需要自行实现与底层磁盘的读写。在ST提供的USB Host驱动中，已经实现了该文件，名为`usbh_msc_fatfs.c`。  
  更进一步，在使用了其他编码例如中文及长文件名时，则需要将`ffunicode.c`包含到自己的项目中。此外，在使用了系统时，还必须将`ffsystem.c`包含到项目中，并按照自己的系统，修改该文件。

### 源码配置 ###

FatFS的配置通过一个名为`ffconf.h`的文件实现。对于每个选项，模板中都有很详细的说明。同时，为减小FatFs占用的空间，一般只开启需要的选项。以下仅对几个特殊的进行注释性说明。

/*---------------------------------------------------------------------------/ / FatFs - Configuration file /---------------------------------------------------------------------------*/
    #define FFCONF_DEF 89352 /* Revision ID */
    /*---------------------------------------------------------------------------/ / Function Configurations /---------------------------------------------------------------------------*/
    #define FF_FS_READONLY 0
    /* This option switches read-only configuration. (0:Read/Write or 1:Read-only) / Read-only configuration removes writing API functions, f_write(), f_sync(), / f_unlink(), f_mkdir(), f_chmod(), f_rename(), f_truncate(), f_getfree() / and optional writing functions as well. */
    
    #define FF_FS_MINIMIZE 0
    /* This option defines minimization level to remove some basic API functions. / / 0: Basic functions are fully enabled. / 1: f_stat(), f_getfree(), f_unlink(), f_mkdir(), f_truncate() and f_rename() / are removed. / 2: f_opendir(), f_readdir() and f_closedir() are removed in addition to 1. / 3: f_lseek() function is removed in addition to 2. */
    
    #define FF_USE_STRFUNC 1
    /* This option switches string functions, f_gets(), f_putc(), f_puts() and f_printf(). / / 0: Disable string functions. / 1: Enable without LF-CRLF conversion. / 2: Enable with LF-CRLF conversion. */
    
    #define FF_USE_FIND 0
    /* This option switches filtered directory read functions, f_findfirst() and / f_findnext(). (0:Disable, 1:Enable 2:Enable with matching altname[] too) */
    
    #define FF_USE_MKFS 0
    /* This option switches f_mkfs() function. (0:Disable or 1:Enable) */
    
    #define FF_USE_FASTSEEK 0
    /* This option switches fast seek function. (0:Disable or 1:Enable) */
    
    #define FF_USE_EXPAND 0
    /* This option switches f_expand function. (0:Disable or 1:Enable) */
    
    #define FF_USE_CHMOD 0
    /* This option switches attribute manipulation functions, f_chmod() and f_utime(). / (0:Disable or 1:Enable) Also FF_FS_READONLY needs to be 0 to enable this option. */
    
    #define FF_USE_LABEL 0
    /* This option switches volume label functions, f_getlabel() and f_setlabel(). / (0:Disable or 1:Enable) */
    
    #define FF_USE_FORWARD 0
    /* This option switches f_forward() function. (0:Disable or 1:Enable) */
    /*---------------------------------------------------------------------------/ / Locale and Namespace Configurations /---------------------------------------------------------------------------*/
    /* Code Page，是字符编码的另一种说法。Code Page包含了一个表，表中的值，用于表示针对某种语言所用的字符集。更简单点说，就是Code Page中，用一个数字编号，表示了所要采用何种字符编码，去编解码相应的值，用于正确显示出相应的字符。*/
    #define FF_CODE_PAGE 932
    /* This option specifies the OEM code page to be used on the target system. / Incorrect code page setting can cause a file open failure. / / 437 - U.S. / 720 - Arabic / 737 - Greek / 771 - KBL / 775 - Baltic / 850 - Latin 1 / 852 - Latin 2 / 855 - Cyrillic / 857 - Turkish / 860 - Portuguese / 861 - Icelandic / 862 - Hebrew / 863 - Canadian French / 864 - Arabic / 865 - Nordic / 866 - Russian / 869 - Greek 2 / 932 - Japanese (DBCS) / 936 - Simplified Chinese (DBCS) / 949 - Korean (DBCS) / 950 - Traditional Chinese (DBCS) / 0 - Include all code pages above and configured by f_setcp() */
    /* 长文件名。这个是微软的专利！开启后 必须包含 ffunicode.c */
    #define FF_USE_LFN 0
    #define FF_MAX_LFN 255
    /* The FF_USE_LFN switches the support for LFN (long file name). / / 0: Disable LFN. FF_MAX_LFN has no effect. / 1: Enable LFN with static working buffer on the BSS. Always NOT thread-safe. / 2: Enable LFN with dynamic working buffer on the STACK. / 3: Enable LFN with dynamic working buffer on the HEAP. / / To enable the LFN, ffunicode.c needs to be added to the project. The LFN function / requiers certain internal working buffer occupies (FF_MAX_LFN + 1) * 2 bytes and / additional (FF_MAX_LFN + 44) / 15 * 32 bytes when exFAT is enabled. / The FF_MAX_LFN defines size of the working buffer in UTF-16 code unit and it can / be in range of 12 to 255. It is recommended to be set 255 to fully support LFN / specification. / When use stack for the working buffer, take care on stack overflow. When use heap / memory for the working buffer, memory management functions, ff_memalloc() and / ff_memfree() in ffsystem.c, need to be added to the project. */
    /* 必须开启 Unicode支持 */
    #define FF_LFN_UNICODE 0
    /* This option switches the character encoding on the API when LFN is enabled. / / 0: ANSI/OEM in current CP (TCHAR = char) / 1: Unicode in UTF-16 (TCHAR = WCHAR) / 2: Unicode in UTF-8 (TCHAR = char) / / Also behavior of string I/O functions will be affected by this option. / When LFN is not enabled, this option has no effect. */
    
    #define FF_LFN_BUF 255
    #define FF_SFN_BUF 12
    /* This set of options defines size of file name members in the FILINFO structure / which is used to read out directory items. These values should be suffcient for / the file names to read. The maximum possible length of the read file name depends / on character encoding. When LFN is not enabled, these options have no effect. */
    
    #define FF_STRF_ENCODE 3
    /* When FF_LFN_UNICODE >= 1 with LFN enabled, string I/O functions, f_gets(), / f_putc(), f_puts and f_printf() convert the character encoding in it. / This option selects assumption of character encoding ON THE FILE to be / read/written via those functions. / / 0: ANSI/OEM in current CP / 1: Unicode in UTF-16LE / 2: Unicode in UTF-16BE / 3: Unicode in UTF-8 */
    
    #define FF_FS_RPATH 0
    /* This option configures support for relative path. / / 0: Disable relative path and remove related functions. / 1: Enable relative path. f_chdir() and f_chdrive() are available. / 2: f_getcwd() function is available in addition to 1. */
    /*---------------------------------------------------------------------------/ / Drive/Volume Configurations /---------------------------------------------------------------------------*/
    #define FF_VOLUMES 1
    /* Number of volumes (logical drives) to be used. (1-10) */
    
    #define FF_STR_VOLUME_ID 0
    #define FF_VOLUME_STRS "RAM","NAND","CF","SD","SD2","USB","USB2","USB3"
    /* FF_STR_VOLUME_ID switches string support for volume ID. / When FF_STR_VOLUME_ID is set to 1, also pre-defined strings can be used as drive / number in the path name. FF_VOLUME_STRS defines the drive ID strings for each / logical drives. Number of items must be equal to FF_VOLUMES. Valid characters for / the drive ID strings are: A-Z and 0-9. */
    
    #define FF_MULTI_PARTITION 0
    /* This option switches support for multiple volumes on the physical drive. / By default (0), each logical drive number is bound to the same physical drive / number and only an FAT volume found on the physical drive will be mounted. / When this function is enabled (1), each logical drive number can be bound to / arbitrary physical drive and partition listed in the VolToPart[]. Also f_fdisk() / funciton will be available. */
    
    #define FF_MIN_SS 512
    #define FF_MAX_SS 512
    /* This set of options configures the range of sector size to be supported. (512, / 1024, 2048 or 4096) Always set both 512 for most systems, generic memory card and / harddisk. But a larger value may be required for on-board flash memory and some / type of optical media. When FF_MAX_SS is larger than FF_MIN_SS, FatFs is configured / for variable sector size mode and disk_ioctl() function needs to implement / GET_SECTOR_SIZE command. */
    
    #define FF_USE_TRIM 0
    /* This option switches support for ATA-TRIM. (0:Disable or 1:Enable) / To enable Trim function, also CTRL_TRIM command should be implemented to the / disk_ioctl() function. */
    
    #define FF_FS_NOFSINFO 0
    /* If you need to know correct free space on the FAT32 volume, set bit 0 of this / option, and f_getfree() function at first time after volume mount will force / a full FAT scan. Bit 1 controls the use of last allocated cluster number. / / bit0=0: Use free cluster count in the FSINFO if available. / bit0=1: Do not trust free cluster count in the FSINFO. / bit1=0: Use last allocated cluster number in the FSINFO if available. / bit1=1: Do not trust last allocated cluster number in the FSINFO. */
    
    /*---------------------------------------------------------------------------/ / System Configurations /---------------------------------------------------------------------------*/
    #define FF_FS_TINY 0
    /* This option switches tiny buffer configuration. (0:Normal or 1:Tiny) / At the tiny configuration, size of file object (FIL) is shrinked FF_MAX_SS bytes. / Instead of private sector buffer eliminated from the file object, common sector / buffer in the filesystem object (FATFS) is used for the file data transfer. */
    
    #define FF_FS_EXFAT 0
    /* This option switches support for exFAT filesystem. (0:Disable or 1:Enable) / When enable exFAT, also LFN needs to be enabled. / Note that enabling exFAT discards ANSI C (C89) compatibility. */
    
    #define FF_FS_NORTC 0
    #define FF_NORTC_MON 1
    #define FF_NORTC_MDAY 1
    #define FF_NORTC_YEAR 2017
    /* The option FF_FS_NORTC switches timestamp functiton. If the system does not have / any RTC function or valid timestamp is not needed, set FF_FS_NORTC = 1 to disable / the timestamp function. All objects modified by FatFs will have a fixed timestamp / defined by FF_NORTC_MON, FF_NORTC_MDAY and FF_NORTC_YEAR in local time. / To enable timestamp function (FF_FS_NORTC = 0), get_fattime() function need to be / added to the project to read current time form real-time clock. FF_NORTC_MON, / FF_NORTC_MDAY and FF_NORTC_YEAR have no effect. / These options have no effect at read-only configuration (FF_FS_READONLY = 1). */
    
    #define FF_FS_LOCK 0
    /* The option FF_FS_LOCK switches file lock function to control duplicated file open / and illegal operation to open objects. This option must be 0 when FF_FS_READONLY / is 1. / / 0: Disable file lock function. To avoid volume corruption, application program / should avoid illegal open, remove and rename to the open objects. / >0: Enable file lock function. The value defines how many files/sub-directories / can be opened simultaneously under file lock control. Note that the file / lock control is independent of re-entrancy. */
    #define FF_FS_REENTRANT 0
    #define FF_FS_TIMEOUT 1000
    #define FF_SYNC_t HANDLE
    /* The option FF_FS_REENTRANT switches the re-entrancy (thread safe) of the FatFs / module itself. Note that regardless of this option, file access to different / volume is always re-entrant and volume control functions, f_mount(), f_mkfs() / and f_fdisk() function, are always not re-entrant. Only file/directory access / to the same volume is under control of this function. / / 0: Disable re-entrancy. FF_FS_TIMEOUT and FF_SYNC_t have no effect. / 1: Enable re-entrancy. Also user provided synchronization handlers, / ff_req_grant(), ff_rel_grant(), ff_del_syncobj() and ff_cre_syncobj() / function, must be added to the project. Samples are available in / option/syscall.c. / / The FF_FS_TIMEOUT defines timeout period in unit of time tick. / The FF_SYNC_t defines O/S dependent sync object type. e.g. HANDLE, ID, OS_EVENT*, / SemaphoreHandle_t and etc. A header file for O/S definitions needs to be / included somewhere in the scope of ff.h. */
    /* #include <windows.h> // O/S definitions */
    /*--- End of configuration options ---*/

### 注意事项 ###

*  FatFs从R0.13开始，源码结构与之间变化不少，变得更简洁。需要使用者修改了diskio.c和ffsystem.也给出了模板，只需要做对应修改即可。
 *  关于字符编码(Code Page)参考[字符编码详解][Link 1]。字符编码选择错误可能导致读写文件失败！！！
 *  长文件名是微软的专利，使用时需要注意！长文件名使用Unicode编码，因此必须包含`ffunicode.c`。在该文件中，FatFs的作者给出了对应文件编码的转换表和对应的转换函数`ff_convert()`和 `ff_wtoupper()`。

## 参考文档 ##

*  STM32F105xx, STM32F107xx, STM32F2xx and STM32F4xx USB On-The-Go host and device library User manual
 *  Universal Serial Bus Revision 2.0 specification
 *  USB 2.0 On-The-Go Specification Supplement Adopters Agreement
 *  Fatfs 官方文档 http://elm-chan.org/fsw/ff/00index\_e.html

[STM32 _ USB IP_USB_]: https://blog.csdn.net/zcshoucsdn/article/details/81257314
[Fatfs]: http://elm-chan.org/fsw/ff/00index_e.html
[USB Host]: /images/20220602/aa74bdd2dcce48ba8c0b5ea93fcd8111.png
[USBHostUser]: /images/20220602/265f109071414571bcaa088697059ef9.png
[2020112511192552.png_pic_center]: /images/20220602/055ed881594b44cfb4c1bc8f4f69002a.png
[FatfsFolder]: /images/20220602/c387953076464b3d83119d0a0e158548.png
[Link 1]: https://www.crifan.com/files/doc/docbook/char_encoding/release/html/char_encoding.html