linux USB子系统（一）

来源：互联网发布：ipad怎么装windows系统编辑：程序博客网时间：2024/04/26 15:42

框架

这里写图片描述

数据结构

usb_dev结构体

struct usb_device {    ...    enum usb_device_state   state;    enum usb_device_speed   speed;    ....    struct usb_device *parent;    struct usb_bus *bus;    //断点0     struct usb_host_endpoint ep0;    //设备模型    struct device dev;    //设备描述符    struct usb_device_descriptor descriptor;    //所有的配置    struct usb_host_config *config;    //active配置    struct usb_host_config *actconfig;    struct usb_host_endpoint *ep_in[16];    struct usb_host_endpoint *ep_out[16];    char **rawdescriptors;    unsigned short bus_mA;    u8 portnum;    u8 level;    ....    //hub    int maxchild;    struct usb_device *children[USB_MAXCHILDREN];    ....};

描述符：

struct usb_device_descriptor {    __u8  bLength;    __u8  bDescriptorType;    __le16 bcdUSB; //1.0 or 2.0    __u8  bDeviceClass; //hid,cdc，etc    __u8  bDeviceSubClass;    __u8  bDeviceProtocol;    __u8  bMaxPacketSize0; //端点0数据大小    __le16 idVendor;//    __le16 idProduct;//    __le16 bcdDevice;    __u8  iManufacturer;    __u8  iProduct;    __u8  iSerialNumber;    __u8  bNumConfigurations;} __attribute__ ((packed));struct usb_config_descriptor {    __u8  bLength;    __u8  bDescriptorType;    __le16 wTotalLength;    __u8  bNumInterfaces; //itfa ？    __u8  bConfigurationValue;    __u8  iConfiguration;    __u8  bmAttributes;//供电模式    __u8  bMaxPower;} __attribute__ ((packed));struct usb_interface_descriptor {    __u8  bLength;    __u8  bDescriptorType;    __u8  bInterfaceNumber; //what intf    __u8  bAlternateSetting;    __u8  bNumEndpoints;//端点数    __u8  bInterfaceClass;//接口类    __u8  bInterfaceSubClass;    __u8  bInterfaceProtocol;//接口协议    __u8  iInterface;} __attribute__ ((packed));struct usb_endpoint_descriptor {    __u8  bLength;    __u8  bDescriptorType;    __u8  bEndpointAddress;//端点地址    __u8  bmAttributes;//端点属性 等时 or blk    __le16 wMaxPacketSize; //数据包大小    __u8  bInterval;//间隔传输时间    /* NOTE:  these two are _only_ in audio endpoints. */    /* use USB_DT_ENDPOINT*_SIZE in bLength, not sizeof. */    __u8  bRefresh;    __u8  bSynchAddress;} __attribute__ ((packed));

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