Linux USB驱动数据结构

struct usb_ctrlrequest
{
    __u8 bRequestType;
    __u8 bRequest;
    __le16 wValue;
    __le16 wIndex;
    __le16 wLength;
} __attribute__ ((packed));

struct usb_wireless_ep_comp_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bMaxBurst;
    __u8  bMaxSequence;
    __le16 wMaxStreamDelay;
    __le16 wOverTheAirPacketSize;
    __u8  bOverTheAirInterval;
    __u8  bmCompAttributes;
#define USB_ENDPOINT_SWITCH_MASK    0x03    /* in bmCompAttributes */
#define USB_ENDPOINT_SWITCH_NO        0
#define USB_ENDPOINT_SWITCH_SWITCH    1
#define USB_ENDPOINT_SWITCH_SCALE    2
} __attribute__((packed));

struct usb_wireless_cap_descriptor
{    /* Ultra Wide Band */
    __u8  bLength;
    __u8  bDescriptorType;
    __u8  bDevCapabilityType;

__u8  bmAttributes;
#define    USB_WIRELESS_P2P_DRD        (1 << 1)
#define    USB_WIRELESS_BEACON_MASK    (3 << 2)
#define    USB_WIRELESS_BEACON_SELF    (1 << 2)
#define    USB_WIRELESS_BEACON_DIRECTED    (2 << 2)
#define    USB_WIRELESS_BEACON_NONE    (3 << 2)
    __le16 wPHYRates;    /* bit rates, Mbps */
#define    USB_WIRELESS_PHY_53        (1 << 0)    /* always set */
#define    USB_WIRELESS_PHY_80        (1 << 1)
#define    USB_WIRELESS_PHY_107        (1 << 2)    /* always set */
#define    USB_WIRELESS_PHY_160        (1 << 3)
#define    USB_WIRELESS_PHY_200        (1 << 4)    /* always set */
#define    USB_WIRELESS_PHY_320        (1 << 5)
#define    USB_WIRELESS_PHY_400        (1 << 6)
#define    USB_WIRELESS_PHY_480        (1 << 7)
    __u8  bmTFITXPowerInfo;    /* TFI power levels */
    __u8  bmFFITXPowerInfo;    /* FFI power levels */
    __le16 bmBandGroup;
    __u8  bReserved;
} __attribute__((packed));

struct usb_string_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__le16 wData[1];        /* UTF-16LE encoded */
} __attribute__ ((packed));

struct usb_security_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__le16 wTotalLength;
    __u8  bNumEncryptionTypes;
} __attribute__((packed));

struct usb_qualifier_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__le16 bcdUSB;
    __u8  bDeviceClass;
    __u8  bDeviceSubClass;
    __u8  bDeviceProtocol;
    __u8  bMaxPacketSize0;
    __u8  bNumConfigurations;
    __u8  bRESERVED;
} __attribute__ ((packed));

struct usb_otg_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bmAttributes;    /* support for HNP, SRP, etc */
} __attribute__ ((packed));

struct usb_key_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  tTKID[3];
    __u8  bReserved;
    __u8  bKeyData[0];
} __attribute__((packed));

struct usb_interface_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bInterfaceNumber;
    __u8  bAlternateSetting;
    __u8  bNumEndpoints;
    __u8  bInterfaceClass;
    __u8  bInterfaceSubClass;
    __u8  bInterfaceProtocol;
    __u8  iInterface;
} __attribute__ ((packed));

struct usb_interface_assoc_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bFirstInterface;
    __u8  bInterfaceCount;
    __u8  bFunctionClass;
    __u8  bFunctionSubClass;
    __u8  bFunctionProtocol;
    __u8  iFunction;
} __attribute__ ((packed));

struct usb_handshake
{
    __u8 bMessageNumber;
    __u8 bStatus;
    __u8 tTKID[3];
    __u8 bReserved;
    __u8 CDID[16];
    __u8 nonce[16];
    __u8 MIC[8];
} __attribute__((packed));

struct usb_endpoint_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bEndpointAddress;
    __u8  bmAttributes;
    __le16 wMaxPacketSize;
    __u8  bInterval;

/* NOTE:  these two are _only_ in audio endpoints. */
    /* use USB_DT_ENDPOINT*_SIZE in bLength, not sizeof. */
    __u8  bRefresh;
    __u8  bSynchAddress;
} __attribute__ ((packed));

struct usb_encryption_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__u8  bEncryptionType;
#define    USB_ENC_TYPE_UNSECURE        0
#define    USB_ENC_TYPE_WIRED        1    /* non-wireless mode */
#define    USB_ENC_TYPE_CCM_1        2    /* aes128/cbc session */
#define    USB_ENC_TYPE_RSA_1        3    /* rsa3072/sha1 auth */
    __u8  bEncryptionValue;        /* use in SET_ENCRYPTION */
    __u8  bAuthKeyIndex;
} __attribute__((packed));

struct usb_device_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

__le16 bcdUSB;
    __u8  bDeviceClass;
    __u8  bDeviceSubClass;
    __u8  bDeviceProtocol;
    __u8  bMaxPacketSize0;
    __le16 idVendor;
    __le16 idProduct;
    __le16 bcdDevice;
    __u8  iManufacturer;
    __u8  iProduct;
    __u8  iSerialNumber;
    __u8  bNumConfigurations;
} __attribute__ ((packed));

struct usb_dev_cap_header
{
    __u8  bLength;
    __u8  bDescriptorType;
    __u8  bDevCapabilityType;
} __attribute__((packed));

struct usb_descriptor_header
{
    __u8  bLength;
    __u8  bDescriptorType;
} __attribute__ ((packed));

struct usb_debug_descriptor
{
    __u8  bLength;
    __u8  bDescriptorType;

/* bulk endpoints with 8 byte maxpacket */
    __u8  bDebugInEndpoint;
    __u8  bDebugOutEndpoint;
} __attribute__((packed));

struct usb_connection_context {
    __u8 CHID[16];        /* persistent host id */
    __u8 CDID[16];        /* device id (unique w/in host context) */
    __u8 CK[16];        /* connection key */
} __attribute__((packed));

struct usb_config_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;

__le16 wTotalLength;
    __u8  bNumInterfaces;
    __u8  bConfigurationValue;
    __u8  iConfiguration;
    __u8  bmAttributes;
    __u8  bMaxPower;
} __attribute__ ((packed));

struct usb_bos_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;

__le16 wTotalLength;
    __u8  bNumDeviceCaps;
} __attribute__((packed));

struct set_config_request {
    struct usb_device    *udev;
    int            config;
    struct work_struct    work;
};

struct usb_sg_request {
    int            status;
    size_t            bytes;

/*
     * members below are private: to usbcore,
     * and are not provided for driver access!
     */
    spinlock_t        lock;

struct usb_device    *dev;
    int            pipe;
    struct scatterlist    *sg;
    int            nents;

int            entries;
    struct urb        **urbs;

int            count;
    struct completion    complete;
};

int usb_sg_init (
    struct usb_sg_request    *io,
    struct usb_device    *dev,
    unsigned        pipe,
    unsigned        period,
    struct scatterlist    *sg,
    int            nents,
    size_t            length,
    gfp_t            mem_flags
);

struct usb_iso_packet_descriptor {
    unsigned int offset;
    unsigned int length;        /* expected length */
    unsigned int actual_length;
    int status;
};

struct usb_interface_cache {
    unsigned num_altsetting;    /* number of alternate settings */
    struct kref ref;        /* reference counter */

/* variable-length array of alternate settings for this interface,
     * stored in no particular order */
    struct usb_host_interface altsetting[0];
};

struct usb_interface {
    /* array of alternate settings for this interface,
     * stored in no particular order */
    struct usb_host_interface *altsetting;

struct usb_host_interface *cur_altsetting;    /* the currently
                     * active alternate setting */
    unsigned num_altsetting;    /* number of alternate settings */

int minor;            /* minor number this interface is
                     * bound to */
    enum usb_interface_condition condition;        /* state of binding */
    unsigned is_active:1;        /* the interface is not suspended */
    unsigned needs_remote_wakeup:1;    /* driver requires remote wakeup */

struct device dev;        /* interface specific device info */
    struct device *usb_dev;        /* pointer to the usb class's device, if any */
    int pm_usage_cnt;        /* usage counter for autosuspend */
};

struct usb_host_interface {
    struct usb_interface_descriptor    desc;

/* array of desc.bNumEndpoint endpoints associated with this
     * interface setting.  these will be in no particular order.
     */
    struct usb_host_endpoint *endpoint;

char *string;        /* iInterface string, if present */
    unsigned char *extra;   /* Extra descriptors */
    int extralen;
};

struct usb_host_endpoint {
    struct usb_endpoint_descriptor    desc;
    struct list_head        urb_list;
    void                *hcpriv;
    struct ep_device         *ep_dev;    /* For sysfs info */

unsigned char *extra;   /* Extra descriptors */
    int extralen;
};

struct usb_host_config {
    struct usb_config_descriptor    desc;

char *string;        /* iConfiguration string, if present */
    /* the interfaces associated with this configuration,
     * stored in no particular order */
    struct usb_interface *interface[USB_MAXINTERFACES];

/* Interface information available even when this is not the
     * active configuration */
    struct usb_interface_cache *intf_cache[USB_MAXINTERFACES];

unsigned char *extra;   /* Extra descriptors */
    int extralen;
};

struct usb_dynids {
    spinlock_t lock;
    struct list_head list;
};

struct usb_dynid {
    struct list_head node;
    struct usb_device_id id;
};

struct usbdrv_wrap {
    struct device_driver driver;
    int for_devices;
};

struct usb_driver {
    const char *name;

int (*probe) (struct usb_interface *intf,
              const struct usb_device_id *id);

void (*disconnect) (struct usb_interface *intf);

int (*ioctl) (struct usb_interface *intf, unsigned int code,
            void *buf);

int (*suspend) (struct usb_interface *intf, pm_message_t message);
    int (*resume) (struct usb_interface *intf);

void (*pre_reset) (struct usb_interface *intf);
    void (*post_reset) (struct usb_interface *intf);

const struct usb_device_id *id_table;

struct usb_dynids dynids;
    struct usbdrv_wrap drvwrap;
    unsigned int no_dynamic_id:1;
    unsigned int supports_autosuspend:1;
};

struct usb_devmap {
    unsigned long devicemap[128 / (8*sizeof(unsigned long))];
};

struct usb_device_driver {
    const char *name;

int (*probe) (struct usb_device *udev);
    void (*disconnect) (struct usb_device *udev);

int (*suspend) (struct usb_device *udev, pm_message_t message);
    int (*resume) (struct usb_device *udev);
    struct usbdrv_wrap drvwrap;
    unsigned int supports_autosuspend:1;
};

struct usb_device {
    int        devnum;        /* Address on USB bus */
    char        devpath [16];    /* Use in messages: /port/port/... */
    enum usb_device_state    state;    /* configured, not attached, etc */
    enum usb_device_speed    speed;    /* high/full/low (or error) */

struct usb_tt    *tt;         /* low/full speed dev, highspeed hub */
    int        ttport;        /* device port on that tt hub */

unsigned int toggle[2];        /* one bit for each endpoint
                     * ([0] = IN, [1] = OUT) */

struct usb_device *parent;    /* our hub, unless we're the root */
    struct usb_bus *bus;        /* Bus we're part of */
    struct usb_host_endpoint ep0;

struct device dev;        /* Generic device interface */

struct usb_device_descriptor descriptor;/* Descriptor */
    struct usb_host_config *config;    /* All of the configs */

struct usb_host_config *actconfig;/* the active configuration */
    struct usb_host_endpoint *ep_in[16];
    struct usb_host_endpoint *ep_out[16];

char **rawdescriptors;        /* Raw descriptors for each config */

unsigned short bus_mA;        /* Current available from the bus */
    u8 portnum;            /* Parent port number (origin 1) */
    u8 level;            /* Number of USB hub ancestors */

unsigned discon_suspended:1;    /* Disconnected while suspended */
    unsigned have_langid:1;        /* whether string_langid is valid */
    int string_langid;        /* language ID for strings */

/* static strings from the device */
    char *product;            /* iProduct string, if present */
    char *manufacturer;        /* iManufacturer string, if present */
    char *serial;            /* iSerialNumber string, if present */

struct list_head filelist;
#ifdef CONFIG_USB_DEVICE_CLASS
    struct device *usb_classdev;
#endif
#ifdef CONFIG_USB_DEVICEFS
    struct dentry *usbfs_dentry;    /* usbfs dentry entry for the device */
#endif
    /*
     * Child devices - these can be either new devices
     * (if this is a hub device), or different instances
     * of this same device.
     *
     * Each instance needs its own set of data structures.
     */

int maxchild;            /* Number of ports if hub */
    struct usb_device *children[USB_MAXCHILDREN];

int pm_usage_cnt;        /* usage counter for autosuspend */
    u32 quirks;            /* quirks of the whole device */

#ifdef CONFIG_PM
    struct delayed_work autosuspend; /* for delayed autosuspends */
    struct mutex pm_mutex;        /* protects PM operations */

unsigned long last_busy;    /* time of last use */
    int autosuspend_delay;        /* in jiffies */

unsigned auto_pm:1;        /* autosuspend/resume in progress */
    unsigned do_remote_wakeup:1;    /* remote wakeup should be enabled */
    unsigned autosuspend_disabled:1; /* autosuspend and autoresume */
    unsigned autoresume_disabled:1;  /*  disabled by the user */
#endif
};

struct usb_class_driver {
    char *name;
    const struct file_operations *fops;
    int minor_base;
};

struct usb_bus {
    struct device *controller;    /* host/master side hardware */
    int busnum;            /* Bus number (in order of reg) */
    char *bus_name;            /* stable id (PCI slot_name etc) */
    u8 uses_dma;            /* Does the host controller use DMA? */
    u8 otg_port;            /* 0, or number of OTG/HNP port */
    unsigned is_b_host:1;        /* true during some HNP roleswitches */
    unsigned b_hnp_enable:1;    /* OTG: did A-Host enable HNP? */

int devnum_next;        /* Next open device number in
                     * round-robin allocation */

struct usb_devmap devmap;    /* device address allocation map */
    struct usb_device *root_hub;    /* Root hub */
    struct list_head bus_list;    /* list of busses */

int bandwidth_allocated;    /* on this bus: how much of the time
                     * reserved for periodic (intr/iso)
                     * requests is used, on average?
                     * Units: microseconds/frame.
                     * Limits: Full/low speed reserve 90%,
                     * while high speed reserves 80%.
                     */
    int bandwidth_int_reqs;        /* number of Interrupt requests */
    int bandwidth_isoc_reqs;    /* number of Isoc. requests */

#ifdef CONFIG_USB_DEVICEFS
    struct dentry *usbfs_dentry;    /* usbfs dentry entry for the bus */
#endif
    struct class_device *class_dev;    /* class device for this bus */

#if defined(CONFIG_USB_MON)
    struct mon_bus *mon_bus;    /* non-null when associated */
    int monitored;            /* non-zero when monitored */
#endif
};

struct urb
{
    /* private: usb core and host controller only fields in the urb */
    struct kref kref;        /* reference count of the URB */
    spinlock_t lock;        /* lock for the URB */
    void *hcpriv;            /* private data for host controller */
    atomic_t use_count;        d/* concurrent submissions counter */
    u8 reject;            /* submissions will fail */

/* public: documented fields in the urb that can be used by drivers */
    struct list_head urb_list;    /* list head for use by the urb's
                     * current owner */
    struct usb_device *dev;     /* (in) pointer to associated device */
    unsigned int pipe;        /* (in) pipe information */
    int status;            /* (return) non-ISO status */
    unsigned int transfer_flags;    /* (in) URB_SHORT_NOT_OK | ...*/
    void *transfer_buffer;        /* (in) associated data buffer */
    dma_addr_t transfer_dma;    /* (in) dma addr for transfer_buffer */
    int transfer_buffer_length;    /* (in) data buffer length */
    int actual_length;        /* (return) actual transfer length */
    unsigned char *setup_packet;    /* (in) setup packet (control only) */
    dma_addr_t setup_dma;        /* (in) dma addr for setup_packet */
    int start_frame;        /* (modify) start frame (ISO) */
    int number_of_packets;        /* (in) number of ISO packets */
    int interval;            /* (modify) transfer interval
                     * (INT/ISO) */
    int error_count;        /* (return) number of ISO errors */
    void *context;            /* (in) context for completion */
    usb_complete_t complete;    /* (in) completion routine */
    struct usb_iso_packet_descriptor iso_frame_desc[0];
                    /* (in) ISO ONLY */
};

struct dev_state {
    struct list_head list;      /* state list */
    struct usb_device *dev;
    struct file *file;
    spinlock_t lock;            /* protects the async urb lists */
    struct list_head async_pending;
    struct list_head async_completed;
    wait_queue_head_t wait;     /* wake up if a request completed */
    unsigned int discsignr;
    struct pid *disc_pid;
    uid_t disc_uid, disc_euid;
    void __user *disccontext;
    unsigned long ifclaimed;
    u32 secid;
};

struct bus_attribute {
    struct attribute    attr;
    ssize_t (*show)(struct bus_type *, char * buf);
    ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
};

struct bus_type {
    const char        * name;
    struct module        * owner;

struct kset        subsys;
    struct kset        drivers;
    struct kset        devices;
    struct klist        klist_devices;
    struct klist        klist_drivers;

struct blocking_notifier_head bus_notifier;

struct bus_attribute    * bus_attrs;
    struct device_attribute    * dev_attrs;
    struct driver_attribute    * drv_attrs;
    struct bus_attribute drivers_autoprobe_attr;
    struct bus_attribute drivers_probe_attr;

int        (*match)(struct device * dev, struct device_driver * drv);
    int        (*uevent)(struct device *dev, char **envp,
                  int num_envp, char *buffer, int buffer_size);
    int        (*probe)(struct device * dev);
    int        (*remove)(struct device * dev);
    void        (*shutdown)(struct device * dev);

int (*suspend)(struct device * dev, pm_message_t state);
    int (*suspend_late)(struct device * dev, pm_message_t state);
    int (*resume_early)(struct device * dev);
    int (*resume)(struct device * dev);

unsigned int drivers_autoprobe:1;
};

struct class_attribute {
    struct attribute    attr;
    ssize_t (*show)(struct class *, char * buf);
    ssize_t (*store)(struct class *, const char * buf, size_t count);
};

struct class_device {
    struct list_head    node;

struct kobject        kobj;
    struct class        * class;    /* required */
    dev_t            devt;        /* dev_t, creates the sysfs "dev" */
    struct class_device_attribute *devt_attr;
    struct class_device_attribute uevent_attr;
    struct device        * dev;        /* not necessary, but nice to have */
    void            * class_data;    /* class-specific data */
    struct class_device    *parent;    /* parent of this child device, if there is one */
    struct attribute_group  ** groups;    /* optional groups */

void    (*release)(struct class_device *dev);
    int    (*uevent)(struct class_device *dev, char **envp,
               int num_envp, char *buffer, int buffer_size);
    char    class_id[BUS_ID_SIZE];    /* unique to this class */
};

struct class_device_attribute {
    struct attribute    attr;
    ssize_t (*show)(struct class_device *, char * buf);
    ssize_t (*store)(struct class_device *, const char * buf, size_t count);
};

struct class_interface {
    struct list_head    node;
    struct class        *class;

int (*add)    (struct class_device *, struct class_interface *);
    void (*remove)    (struct class_device *, struct class_interface *);
    int (*add_dev)        (struct device *, struct class_interface *);
    void (*remove_dev)    (struct device *, struct class_interface *);
};

struct device {
    struct klist        klist_children;
    struct klist_node    knode_parent;        /* node in sibling list */
    struct klist_node    knode_driver;
    struct klist_node    knode_bus;
    struct device        *parent;

struct kobject kobj;
    char    bus_id[BUS_ID_SIZE];    /* position on parent bus */
    struct device_type    *type;
    unsigned        is_registered:1;
    unsigned        uevent_suppress:1;
    struct device_attribute uevent_attr;
    struct device_attribute *devt_attr;

struct semaphore    sem;    /* semaphore to synchronize calls to
                     * its driver.
                     */

struct bus_type    * bus;        /* type of bus device is on */
    struct device_driver *driver;    /* which driver has allocated this
                       device */
    void        *driver_data;    /* data private to the driver */
    void        *platform_data;    /* Platform specific data, device
                       core doesn't touch it */
    struct dev_pm_info    power;

#ifdef CONFIG_NUMA
    int        numa_node;    /* NUMA node this device is close to */
#endif
    u64        *dma_mask;    /* dma mask (if dma'able device) */
    u64        coherent_dma_mask;/* Like dma_mask, but for
                         alloc_coherent mappings as
                         not all hardware supports
                         64 bit addresses for consistent
                         allocations such descriptors. */

struct list_head    dma_pools;    /* dma pools (if dma'ble) */

struct dma_coherent_mem    *dma_mem; /* internal for coherent mem
                         override */
    /* arch specific additions */
    struct dev_archdata    archdata;

spinlock_t        devres_lock;
    struct list_head    devres_head;

/* class_device migration path */
    struct list_head    node;
    struct class        *class;
    dev_t            devt;        /* dev_t, creates the sysfs "dev" */
    struct attribute_group    **groups;    /* optional groups */

void    (*release)(struct device * dev);
};

struct device_attribute {
    struct attribute    attr;
    ssize_t (*show)(struct device *dev, struct device_attribute *attr,
            char *buf);
    ssize_t (*store)(struct device *dev, struct device_attribute *attr,
             const char *buf, size_t count);
};

struct device_driver {
    const char        * name;
    struct bus_type        * bus;

struct kobject        kobj;
    struct klist        klist_devices;
    struct klist_node    knode_bus;

struct module        * owner;
    const char         * mod_name;    /* used for built-in modules */
    struct module_kobject    * mkobj;

int    (*probe)    (struct device * dev);
    int    (*remove)    (struct device * dev);
    void    (*shutdown)    (struct device * dev);
    int    (*suspend)    (struct device * dev, pm_message_t state);
    int    (*resume)    (struct device * dev);
};

struct device_type {
    const char *name;
    struct attribute_group **groups;
    int (*uevent)(struct device *dev, char **envp, int num_envp,
              char *buffer, int buffer_size);
    void (*release)(struct device *dev);
    int (*suspend)(struct device * dev, pm_message_t state);
    int (*resume)(struct device * dev);
};

struct driver_attribute {
    struct attribute    attr;
    ssize_t (*show)(struct device_driver *, char * buf);
    ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
};

struct find_interface_arg {
    int minor;
    struct usb_interface *interface;
};

struct usb_device_id {
    /* which fields to match against? */
    __u16        match_flags;

/* Used for product specific matches; range is inclusive */
    __u16        idVendor;
    __u16        idProduct;
    __u16        bcdDevice_lo;
    __u16        bcdDevice_hi;

/* Used for device class matches */
    __u8        bDeviceClass;
    __u8        bDeviceSubClass;
    __u8        bDeviceProtocol;

/* Used for interface class matches */
    __u8        bInterfaceClass;
    __u8        bInterfaceSubClass;
    __u8        bInterfaceProtocol;

/* not matched against */
    kernel_ulong_t    driver_info;
};

struct hc_driver {
    const char    *description;    /* "ehci-hcd" etc */
    const char    *product_desc;    /* product/vendor string */
    size_t        hcd_priv_size;    /* size of private data */

/* irq handler */
    irqreturn_t    (*irq) (struct usb_hcd *hcd);

int    flags;
#define    HCD_MEMORY    0x0001        /* HC regs use memory (else I/O) */
#define    HCD_LOCAL_MEM    0x0002        /* HC needs local memory */
#define    HCD_USB11    0x0010        /* USB 1.1 */
#define    HCD_USB2    0x0020        /* USB 2.0 */

/* called to init HCD and root hub */
    int    (*reset) (struct usb_hcd *hcd);
    int    (*start) (struct usb_hcd *hcd);

/* NOTE:  these suspend/resume calls relate to the HC as
     * a whole, not just the root hub; they're for PCI bus glue.
     */
    /* called after suspending the hub, before entering D3 etc */
    int    (*pci_suspend) (struct usb_hcd *hcd, pm_message_t message);

/* called after entering D0 (etc), before resuming the hub */
    int    (*pci_resume) (struct usb_hcd *hcd);

/* cleanly make HCD stop writing memory and doing I/O */
    void    (*stop) (struct usb_hcd *hcd);

/* shutdown HCD */
    void    (*shutdown) (struct usb_hcd *hcd);

/* return current frame number */
    int    (*get_frame_number) (struct usb_hcd *hcd);

/* manage i/o requests, device state */
    int    (*urb_enqueue)(struct usb_hcd *hcd,
                struct urb *urb, gfp_t mem_flags);
    int    (*urb_dequeue)(struct usb_hcd *hcd,
                struct urb *urb, int status);

/* hw synch, freeing endpoint resources that urb_dequeue can't */
    void     (*endpoint_disable)(struct usb_hcd *hcd,
            struct usb_host_endpoint *ep);

/* root hub support */
    int    (*hub_status_data) (struct usb_hcd *hcd, char *buf);
    int    (*hub_control) (struct usb_hcd *hcd,
                u16 typeReq, u16 wValue, u16 wIndex,
                char *buf, u16 wLength);
    int    (*bus_suspend)(struct usb_hcd *);
    int    (*bus_resume)(struct usb_hcd *);
    int    (*start_port_reset)(struct usb_hcd *, unsigned port_num);

/* force handover of high-speed port to full-speed companion */
    void    (*relinquish_port)(struct usb_hcd *, int);
        /* has a port been handed over to a companion? */
    int    (*port_handed_over)(struct usb_hcd *, int);
};

struct hcd_timeout {    /* timeouts we allocate */
    struct list_head    timeout_list;
    struct timer_list    timer;
};

struct usb_hcd {

/*
     * housekeeping
     */
    struct usb_bus        self;        /* hcd is-a bus */
    struct kref        kref;        /* reference counter */

const char        *product_desc;    /* product/vendor string */
    char            irq_descr[24];    /* driver + bus # */

struct timer_list    rh_timer;    /* drives root-hub polling */
    struct urb        *status_urb;    /* the current status urb */
#ifdef CONFIG_PM
    struct work_struct    wakeup_work;    /* for remote wakeup */
#endif

/*
     * hardware info/state
     */
    const struct hc_driver    *driver;    /* hw-specific hooks */

/* Flags that need to be manipulated atomically */
    unsigned long        flags;
#define HCD_FLAG_HW_ACCESSIBLE    0x00000001
#define HCD_FLAG_SAW_IRQ    0x00000002

unsigned        rh_registered:1;/* is root hub registered? */

/* The next flag is a stopgap, to be removed when all the HCDs
     * support the new root-hub polling mechanism. */
    unsigned        uses_new_polling:1;
    unsigned        poll_rh:1;    /* poll for rh status? */
    unsigned        poll_pending:1;    /* status has changed? */
    unsigned        wireless:1;    /* Wireless USB HCD */
    unsigned        authorized_default:1;
    unsigned        has_tt:1;    /* Integrated TT in root hub */

int            irq;        /* irq allocated */
    void __iomem        *regs;        /* device memory/io */
    u64            rsrc_start;    /* memory/io resource start */
    u64            rsrc_len;    /* memory/io resource length */
    unsigned        power_budget;    /* in mA, 0 = no limit */

#define HCD_BUFFER_POOLS    4
    struct dma_pool        *pool [HCD_BUFFER_POOLS];

int            state;
#    define    __ACTIVE        0x01
#    define    __SUSPEND        0x04
#    define    __TRANSIENT        0x80

#    define    HC_STATE_HALT        0
#    define    HC_STATE_RUNNING    (__ACTIVE)
#    define    HC_STATE_QUIESCING    (__SUSPEND|__TRANSIENT|__ACTIVE)
#    define    HC_STATE_RESUMING    (__SUSPEND|__TRANSIENT)
#    define    HC_STATE_SUSPENDED    (__SUSPEND)

#define    HC_IS_RUNNING(state) ((state) & __ACTIVE)
#define    HC_IS_SUSPENDED(state) ((state) & __SUSPEND)

/* more shared queuing code would be good; it should support
     * smarter scheduling, handle transaction translators, etc;
     * input size of periodic table to an interrupt scheduler.
     * (ohci 32, uhci 1024, ehci 256/512/1024).
     */

/* The HC driver's private data is stored at the end of
     * this structure.
     */
    unsigned long hcd_priv[0]
            __attribute__ ((aligned(sizeof(unsigned long))));
};

struct usb_mon_operations {
    void (*urb_submit)(struct usb_bus *bus, struct urb *urb);
    void (*urb_submit_error)(struct usb_bus *bus, struct urb *urb, int err);
    void (*urb_complete)(struct usb_bus *bus, struct urb *urb, int status);
    /* void (*urb_unlink)(struct usb_bus *bus, struct urb *urb); */
};

struct usb_busmap {
    unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
};

struct usb_device_status {
    unsigned int lastev;
};

struct class_info {
    int class;
    char *class_name;
};

struct dev_state {
    struct list_head list;      /* state list */
    struct usb_device *dev;
    struct file *file;
    spinlock_t lock;            /* protects the async urb lists */
    struct list_head async_pending;
    struct list_head async_completed;
    wait_queue_head_t wait;     /* wake up if a request completed */
    unsigned int discsignr;
    struct pid *disc_pid;
    uid_t disc_uid, disc_euid;
    void __user *disccontext;
    unsigned long ifclaimed;
    u32 secid;
};

struct async {
    struct list_head asynclist;
    struct dev_state *ps;
    struct pid *pid;
    uid_t uid, euid;
    unsigned int signr;
    unsigned int ifnum;
    void __user *userbuffer;
    void __user *userurb;
    struct urb *urb;
    int status;
    u32 secid;
};

struct ep_device {
    struct usb_endpoint_descriptor *desc;
    struct usb_device *udev;
    struct device dev;
    int minor;
};
#define to_ep_device(_dev) \
    container_of(_dev, struct ep_device, dev)

struct ep_attribute {
    struct attribute attr;
    ssize_t (*show)(struct usb_device *,
            struct usb_endpoint_descriptor *, char *);
};

static struct endpoint_class {
    struct kref kref;
    struct class *class;
} *ep_class;

static struct usb_class {
    struct kref kref;
    struct class *class;
} *usb_class;

struct usb_hub {
    struct device        *intfdev;    /* the "interface" device */
    struct usb_device    *hdev;
    struct kref        kref;
    struct urb        *urb;        /* for interrupt polling pipe */

/* buffer for urb ... with extra space in case of babble */
    char            (*buffer)[8];
    dma_addr_t        buffer_dma;    /* DMA address for buffer */
    union {
        struct usb_hub_status    hub;
        struct usb_port_status    port;
    }            *status;    /* buffer for status reports */
    struct mutex        status_mutex;    /* for the status buffer */

int            error;        /* last reported error */
    int            nerrors;    /* track consecutive errors */

struct list_head    event_list;    /* hubs w/data or errs ready */
    unsigned long        event_bits[1];    /* status change bitmask */
    unsigned long        change_bits[1];    /* ports with logical connect
                            status change */
    unsigned long        busy_bits[1];    /* ports being reset or
                            resumed */
#if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
#error event_bits[] is too short!
#endif

struct usb_hub_descriptor *descriptor;    /* class descriptor */
    struct usb_tt        tt;        /* Transaction Translator */

unsigned        mA_per_port;    /* current for each child */

unsigned        limited_power:1;
    unsigned        quiescing:1;
    unsigned        disconnected:1;

unsigned        has_indicators:1;
    u8            indicator[USB_MAXCHILDREN];
    struct delayed_work    leds;
    struct delayed_work    init_work;
};

enum hub_activation_type {
    HUB_INIT, HUB_INIT2, HUB_INIT3,
    HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
};

enum hub_quiescing_type {
    HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
};

enum hub_activation_type {
    HUB_INIT, HUB_INIT2, HUB_INIT3,
    HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
};

struct usb_tt {
    struct usb_device    *hub;    /* upstream highspeed hub */
    int            multi;    /* true means one TT per port */
    unsigned        think_time;    /* think time in ns */

/* for control/bulk error recovery (CLEAR_TT_BUFFER) */
    spinlock_t        lock;
    struct list_head    clear_list;    /* of usb_tt_clear */
    struct work_struct            kevent;
};

struct usb_tt_clear {
    struct list_head    clear_list;
    unsigned        tt;
    u16            devinfo;
};

struct usb_port_status {
    __le16 wPortStatus;
    __le16 wPortChange;
} __attribute__ ((packed));

struct usb_hub_status {
    __le16 wHubStatus;
    __le16 wHubChange;
} __attribute__ ((packed));

struct usb_hub_descriptor {
    __u8  bDescLength;
    __u8  bDescriptorType;
    __u8  bNbrPorts;
    __le16 wHubCharacteristics;
    __u8  bPwrOn2PwrGood;
    __u8  bHubContrCurrent;
        /* add 1 bit for hub status change; round to bytes */
    __u8  DeviceRemovable[(USB_MAXCHILDREN + 1 + 7) / 8];
    __u8  PortPwrCtrlMask[(USB_MAXCHILDREN + 1 + 7) / 8];
} __attribute__ ((packed));

enum {
    Opt_devuid, Opt_devgid, Opt_devmode,
    Opt_busuid, Opt_busgid, Opt_busmode,
    Opt_listuid, Opt_listgid, Opt_listmode,
    Opt_err,
};

struct set_config_request {
    struct usb_device    *udev;
    int            config;
    struct work_struct    work;
    struct list_head    node;
};

struct api_context {
    struct completion    done;
    int            status;
};

struct find_interface_arg {
    int minor;
    struct usb_interface *interface;
};

enum
{
    PM_SYS_UNKNOWN = 0x00000000, /* generic */
    PM_SYS_KBC =     0x41d00303, /* keyboard controller */
    PM_SYS_COM =     0x41d00500, /* serial port */
    PM_SYS_IRDA =     0x41d00510, /* IRDA controller */
    PM_SYS_FDC =     0x41d00700, /* floppy controller */
    PM_SYS_VGA =     0x41d00900, /* VGA controller */
    PM_SYS_PCMCIA =     0x41d00e00, /* PCMCIA controller */
};

struct pm_dev
{
    pm_dev_t     type;
    unsigned long     id;
    pm_callback     callback;
    void        *data;

unsigned long     flags;
    unsigned long     state;
    unsigned long     prev_state;

struct list_head entry;
};

struct pm_ops {
    int (*valid)(suspend_state_t state);
    int (*set_target)(suspend_state_t state);
    int (*prepare)(suspend_state_t state);
    int (*enter)(suspend_state_t state);
    int (*finish)(suspend_state_t state);
};

typedef struct pm_message {
    int event;
} pm_message_t;

struct dev_pm_info {
    pm_message_t        power_state;
    unsigned        can_wakeup:1;
#ifdef    CONFIG_PM
    unsigned        should_wakeup:1;
    pm_message_t        prev_state;
    void            * saved_state;
    struct device        * pm_parent;
    struct list_head    entry;
#endif
};

struct usb_hcd {

/*
     * housekeeping
     */
    struct usb_bus        self;        /* hcd is-a bus */
    struct kref        kref;        /* reference counter */

const char        *product_desc;    /* product/vendor string */
    char            irq_descr[24];    /* driver + bus # */

struct timer_list    rh_timer;    /* drives root-hub polling */
    struct urb        *status_urb;    /* the current status urb */
#ifdef CONFIG_PM
    struct work_struct    wakeup_work;    /* for remote wakeup */
#endif

/*
     * hardware info/state
     */
    const struct hc_driver    *driver;    /* hw-specific hooks */

/* Flags that need to be manipulated atomically */
    unsigned long        flags;
#define HCD_FLAG_HW_ACCESSIBLE    0x00000001
#define HCD_FLAG_SAW_IRQ    0x00000002

unsigned        rh_registered:1;/* is root hub registered? */

/* The next flag is a stopgap, to be removed when all the HCDs
     * support the new root-hub polling mechanism. */
    unsigned        uses_new_polling:1;
    unsigned        poll_rh:1;    /* poll for rh status? */
    unsigned        poll_pending:1;    /* status has changed? */
    unsigned        wireless:1;    /* Wireless USB HCD */

int            irq;        /* irq allocated */
    void __iomem        *regs;        /* device memory/io */
    u64            rsrc_start;    /* memory/io resource start */
    u64            rsrc_len;    /* memory/io resource length */
    unsigned        power_budget;    /* in mA, 0 = no limit */

#define HCD_BUFFER_POOLS    4
    struct dma_pool        *pool [HCD_BUFFER_POOLS];

int            state;
#    define    __ACTIVE        0x01
#    define    __SUSPEND        0x04
#    define    __TRANSIENT        0x80

#    define    HC_STATE_HALT        0
#    define    HC_STATE_RUNNING    (__ACTIVE)
#    define    HC_STATE_QUIESCING    (__SUSPEND|__TRANSIENT|__ACTIVE)
#    define    HC_STATE_RESUMING    (__SUSPEND|__TRANSIENT)
#    define    HC_STATE_SUSPENDED    (__SUSPEND)

#define    HC_IS_RUNNING(state) ((state) & __ACTIVE)
#define    HC_IS_SUSPENDED(state) ((state) & __SUSPEND)

/* more shared queuing code would be good; it should support
     * smarter scheduling, handle transaction translators, etc;
     * input size of periodic table to an interrupt scheduler.
     * (ohci 32, uhci 1024, ehci 256/512/1024).
     */

/* The HC driver's private data is stored at the end of
     * this structure.
     */
    unsigned long hcd_priv[0]
            __attribute__ ((aligned (sizeof(unsigned long))));
};

struct uhci_hcd {

/* debugfs */
    struct dentry *dentry;

/* Grabbed from PCI */
    unsigned long io_addr;

struct dma_pool *qh_pool;
    struct dma_pool *td_pool;

struct uhci_td *term_td;    /* Terminating TD, see UHCI bug */
    struct uhci_qh *skelqh[UHCI_NUM_SKELQH];    /* Skeleton QHs */
    struct uhci_qh *next_qh;    /* Next QH to scan */

spinlock_t lock;

dma_addr_t frame_dma_handle;    /* Hardware frame list */
    __le32 *frame;
    void **frame_cpu;        /* CPU's frame list */

enum uhci_rh_state rh_state;
    unsigned long auto_stop_time;        /* When to AUTO_STOP */

unsigned int frame_number;        /* As of last check */
    unsigned int is_stopped;
#define UHCI_IS_STOPPED        9999        /* Larger than a frame # */
    unsigned int last_iso_frame;        /* Frame of last scan */
    unsigned int cur_iso_frame;        /* Frame for current scan */

unsigned int scan_in_progress:1;    /* Schedule scan is running */
    unsigned int need_rescan:1;        /* Redo the schedule scan */
    unsigned int dead:1;            /* Controller has died */
    unsigned int working_RD:1;        /* Suspended root hub doesn't
                           need to be polled */
    unsigned int is_initialized:1;        /* Data structure is usable */
    unsigned int fsbr_is_on:1;        /* FSBR is turned on */
    unsigned int fsbr_is_wanted:1;        /* Does any URB want FSBR? */
    unsigned int fsbr_expiring:1;        /* FSBR is timing out */

struct timer_list fsbr_timer;        /* For turning off FBSR */

/* Support for port suspend/resume/reset */
    unsigned long port_c_suspend;        /* Bit-arrays of ports */
    unsigned long resuming_ports;
    unsigned long ports_timeout;        /* Time to stop signalling */

struct list_head idle_qh_list;        /* Where the idle QHs live */

int rh_numports;            /* Number of root-hub ports */

wait_queue_head_t waitqh;        /* endpoint_disable waiters */
    int num_waiting;            /* Number of waiters */

int total_load;                /* Sum of array values */
    short load[MAX_PHASE];            /* Periodic allocations */
};

struct uhci_td {
    /* Hardware fields */
    __le32 link;
    __le32 status;
    __le32 token;
    __le32 buffer;

/* Software fields */
    dma_addr_t dma_handle;

struct list_head list;

int frame;            /* for iso: what frame? */
    struct list_head fl_list;
} __attribute__((aligned(16)));

enum uhci_rh_state {
    /* In the following states the HC must be halted.
     * These two must come first. */
    UHCI_RH_RESET,
    UHCI_RH_SUSPENDED,

UHCI_RH_AUTO_STOPPED,
    UHCI_RH_RESUMING,

/* In this state the HC changes from running to halted,
     * so it can legally appear either way. */
    UHCI_RH_SUSPENDING,

/* In the following states it's an error if the HC is halted.
     * These two must come last. */
    UHCI_RH_RUNNING,        /* The normal state */
    UHCI_RH_RUNNING_NODEVS,        /* Running with no devices attached */
};

struct uhci_qh {
    /* Hardware fields */
    __le32 link;            /* Next QH in the schedule */
    __le32 element;            /* Queue element (TD) pointer */

/* Software fields */
    dma_addr_t dma_handle;

struct list_head node;        /* Node in the list of QHs */
    struct usb_host_endpoint *hep;    /* Endpoint information */
    struct usb_device *udev;
    struct list_head queue;        /* Queue of urbps for this QH */
    struct uhci_td *dummy_td;    /* Dummy TD to end the queue */
    struct uhci_td *post_td;    /* Last TD completed */

struct usb_iso_packet_descriptor *iso_packet_desc;
                    /* Next urb->iso_frame_desc entry */
    unsigned long advance_jiffies;    /* Time of last queue advance */
    unsigned int unlink_frame;    /* When the QH was unlinked */
    unsigned int period;        /* For Interrupt and Isochronous QHs */
    short phase;            /* Between 0 and period-1 */
    short load;            /* Periodic time requirement, in us */
    unsigned int iso_frame;        /* Frame # for iso_packet_desc */
    int iso_status;            /* Status for Isochronous URBs */

int state;            /* QH_STATE_xxx; see above */
    int type;            /* Queue type (control, bulk, etc) */
    int skel;            /* Skeleton queue number */

unsigned int initial_toggle:1;    /* Endpoint's current toggle value */
    unsigned int needs_fixup:1;    /* Must fix the TD toggle values */
    unsigned int is_stopped:1;    /* Queue was stopped by error/unlink */
    unsigned int wait_expired:1;    /* QH_WAIT_TIMEOUT has expired */
    unsigned int bandwidth_reserved:1;    /* Periodic bandwidth has
                         * been allocated */
} __attribute__((aligned(16)));

struct urb_priv {
    struct list_head node;        /* Node in the QH's urbp list */

struct urb *urb;

struct uhci_qh *qh;        /* QH for this URB */
    struct list_head td_list;

unsigned fsbr:1;        /* URB wants FSBR */
};

/* embedded in scsi_cmnd */
struct scsi_pointer {
    char *ptr;        /* data pointer */
    int this_residual;    /* left in this buffer */
    struct scatterlist *buffer;    /* which buffer */
    int buffers_residual;    /* how many buffers left */

dma_addr_t dma_handle;

volatile int Status;
    volatile int Message;
    volatile int have_data_in;
    volatile int sent_command;
    volatile int phase;
};

struct scsi_cmnd {
    struct scsi_device *device;
    struct list_head list;  /* scsi_cmnd participates in queue lists */
    struct list_head eh_entry; /* entry for the host eh_cmd_q */
    int eh_eflags;        /* Used by error handlr */
    void (*done) (struct scsi_cmnd *);    /* Mid-level done function */

/*
     * A SCSI Command is assigned a nonzero serial_number before passed
     * to the driver's queue command function.  The serial_number is
     * cleared when scsi_done is entered indicating that the command
     * has been completed.  It currently doesn't have much use other
     * than printk's.  Some lldd's use this number for other purposes.
     * It's almost certain that such usages are either incorrect or
     * meaningless.  Please kill all usages other than printk's.  Also,
     * as this number is always identical to ->pid, please convert
     * printk's to use ->pid, so that we can kill this field.
     */
    unsigned long serial_number;
    /*
     * This is set to jiffies as it was when the command was first
     * allocated.  It is used to time how long the command has
     * been outstanding
     */
    unsigned long jiffies_at_alloc;

int retries;
    int allowed;
    int timeout_per_command;

unsigned char cmd_len;
    enum dma_data_direction sc_data_direction;

/* These elements define the operation we are about to perform */
#define MAX_COMMAND_SIZE    16
    unsigned char cmnd[MAX_COMMAND_SIZE];
    unsigned request_bufflen;    /* Actual request size */

struct timer_list eh_timeout;    /* Used to time out the command. */
    void *request_buffer;        /* Actual requested buffer */

/* These elements define the operation we ultimately want to perform */
    unsigned short use_sg;    /* Number of pieces of scatter-gather */
    unsigned short sglist_len;    /* size of malloc'd scatter-gather list */

unsigned underflow;    /* Return error if less than
                   this amount is transferred */

unsigned transfersize;    /* How much we are guaranteed to
                   transfer with each SCSI transfer
                   (ie, between disconnect /
                   reconnects.   Probably == sector
                   size */

int resid;        /* Number of bytes requested to be
                   transferred less actual number
                   transferred (0 if not supported) */

struct request *request;    /* The command we are
                          working on */

#define SCSI_SENSE_BUFFERSIZE     96
    unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
                /* obtained by REQUEST SENSE when
                 * CHECK CONDITION is received on original
                 * command (auto-sense) */

/* Low-level done function - can be used by low-level driver to point
     *        to completion function.  Not used by mid/upper level code. */
    void (*scsi_done) (struct scsi_cmnd *);

/*
     * The following fields can be written to by the host specific code.
     * Everything else should be left alone.
     */
    struct scsi_pointer SCp;    /* Scratchpad used by some host adapters */

unsigned char *host_scribble;    /* The host adapter is allowed to
                     * call scsi_malloc and get some memory
                     * and hang it here.  The host adapter
                     * is also expected to call scsi_free
                     * to release this memory.  (The memory
                     * obtained by scsi_malloc is guaranteed
                     * to be at an address < 16Mb). */

int result;        /* Status code from lower level driver */

unsigned char tag;    /* SCSI-II queued command tag */
    unsigned long pid;    /* Process ID, starts at 0. Unique per host. */
};

struct scsi_mode_data {
    __u32    length;
    __u16    block_descriptor_length;
    __u8    medium_type;
    __u8    device_specific;
    __u8    header_length;
    __u8    longlba:1;
};

/*
 * sdev state: If you alter this, you also need to alter scsi_sysfs.c
 * (for the ascii descriptions) and the state model enforcer:
 * scsi_lib:scsi_device_set_state().
 */
enum scsi_device_state {
    SDEV_CREATED = 1,    /* device created but not added to sysfs
                 * Only internal commands allowed (for inq) */
    SDEV_RUNNING,        /* device properly configured
                 * All commands allowed */
    SDEV_CANCEL,        /* beginning to delete device
                 * Only error handler commands allowed */
    SDEV_DEL,        /* device deleted
                 * no commands allowed */
    SDEV_QUIESCE,        /* Device quiescent.  No block commands
                 * will be accepted, only specials (which
                 * originate in the mid-layer) */
    SDEV_OFFLINE,        /* Device offlined (by error handling or
                 * user request */
    SDEV_BLOCK,        /* Device blocked by scsi lld.  No scsi
                 * commands from user or midlayer should be issued
                 * to the scsi lld. */
};

struct scsi_device {
    struct Scsi_Host *host;
    struct request_queue *request_queue;

/* the next two are protected by the host->host_lock */
    struct list_head    siblings;   /* list of all devices on this host */
    struct list_head    same_target_siblings; /* just the devices sharing same target id */

/* this is now protected by the request_queue->queue_lock */
    unsigned int device_busy;    /* commands actually active on
                     * low-level. protected by queue_lock. */
    spinlock_t list_lock;
    struct list_head cmd_list;    /* queue of in use SCSI Command structures */
    struct list_head starved_entry;
    struct scsi_cmnd *current_cmnd;    /* currently active command */
    unsigned short queue_depth;    /* How deep of a queue we want */
    unsigned short last_queue_full_depth; /* These two are used by */
    unsigned short last_queue_full_count; /* scsi_track_queue_full() */
    unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
                       jiffie count on our counter, they
                       could all be from the same event. */

unsigned int id, lun, channel;

unsigned int manufacturer;    /* Manufacturer of device, for using
                     * vendor-specific cmd's */
    unsigned sector_size;    /* size in bytes */

void *hostdata;        /* available to low-level driver */
    char type;
    char scsi_level;
    char inq_periph_qual;    /* PQ from INQUIRY data */    
    unsigned char inquiry_len;    /* valid bytes in 'inquiry' */
    unsigned char * inquiry;    /* INQUIRY response data */
    const char * vendor;        /* [back_compat] point into 'inquiry' ... */
    const char * model;        /* ... after scan; point to static string */
    const char * rev;        /* ... "nullnullnullnull" before scan */
    unsigned char current_tag;    /* current tag */
    struct scsi_target      *sdev_target;   /* used only for single_lun */

unsigned int    sdev_bflags; /* black/white flags as also found in
                 * scsi_devinfo.[hc]. For now used only to
                 * pass settings from slave_alloc to scsi
                 * core. */
    unsigned writeable:1;
    unsigned removable:1;
    unsigned changed:1;    /* Data invalid due to media change */
    unsigned busy:1;    /* Used to prevent races */
    unsigned lockable:1;    /* Able to prevent media removal */
    unsigned locked:1;      /* Media removal disabled */
    unsigned borken:1;    /* Tell the Seagate driver to be
                 * painfully slow on this device */
    unsigned disconnect:1;    /* can disconnect */
    unsigned soft_reset:1;    /* Uses soft reset option */
    unsigned sdtr:1;    /* Device supports SDTR messages */
    unsigned wdtr:1;    /* Device supports WDTR messages */
    unsigned ppr:1;        /* Device supports PPR messages */
    unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
    unsigned simple_tags:1;    /* simple queue tag messages are enabled */
    unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
    unsigned single_lun:1;    /* Indicates we should only allow I/O to
                 * one of the luns for the device at a
                 * time. */
    unsigned was_reset:1;    /* There was a bus reset on the bus for
                 * this device */
    unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
                     * because we did a bus reset. */
    unsigned use_10_for_rw:1; /* first try 10-byte read / write */
    unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
    unsigned skip_ms_page_8:1;    /* do not use MODE SENSE page 0x08 */
    unsigned skip_ms_page_3f:1;    /* do not use MODE SENSE page 0x3f */
    unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
    unsigned no_start_on_add:1;    /* do not issue start on add */
    unsigned allow_restart:1; /* issue START_UNIT in error handler */
    unsigned manage_start_stop:1;    /* Let HLD (sd) manage start/stop */
    unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
    unsigned select_no_atn:1;
    unsigned fix_capacity:1;    /* READ_CAPACITY is too high by 1 */
    unsigned guess_capacity:1;    /* READ_CAPACITY might be too high by 1 */
    unsigned retry_hwerror:1;    /* Retry HARDWARE_ERROR */

unsigned int device_blocked;    /* Device returned QUEUE_FULL. */

unsigned int max_device_blocked; /* what device_blocked counts down from  */
#define SCSI_DEFAULT_DEVICE_BLOCKED    3

atomic_t iorequest_cnt;
    atomic_t iodone_cnt;
    atomic_t ioerr_cnt;

int timeout;

struct device        sdev_gendev;
    struct class_device    sdev_classdev;

struct execute_work    ew; /* used to get process context on put */

enum scsi_device_state sdev_state;
    unsigned long        sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));
#define    to_scsi_device(d)    \
    container_of(d, struct scsi_device, sdev_gendev)
#define    class_to_sdev(d)    \
    container_of(d, struct scsi_device, sdev_classdev)
#define transport_class_to_sdev(class_dev) \
    to_scsi_device(class_dev->dev)

#define sdev_printk(prefix, sdev, fmt, a...)    \
    dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)

#define scmd_printk(prefix, scmd, fmt, a...)                \
        (scmd)->request->rq_disk ?                    \
    sdev_printk(prefix, (scmd)->device, "[%s] " fmt,        \
            (scmd)->request->rq_disk->disk_name, ##a) :        \
    sdev_printk(prefix, (scmd)->device, fmt, ##a)

enum scsi_target_state {
    STARGET_RUNNING = 1,
    STARGET_DEL,
};

/*
 * scsi_target: representation of a scsi target, for now, this is only
 * used for single_lun devices. If no one has active IO to the target,
 * starget_sdev_user is NULL, else it points to the active sdev.
 */
struct scsi_target {
    struct scsi_device    *starget_sdev_user;
    struct list_head    siblings;
    struct list_head    devices;
    struct device        dev;
    unsigned int        reap_ref; /* protected by the host lock */
    unsigned int        channel;
    unsigned int        id; /* target id ... replace
                     * scsi_device.id eventually */
    unsigned int        create:1; /* signal that it needs to be added */
    unsigned int        pdt_1f_for_no_lun;    /* PDT = 0x1f */
                        /* means no lun present */

char            scsi_level;
    struct execute_work    ew;
    enum scsi_target_state    state;
    void             *hostdata; /* available to low-level driver */
    unsigned long        starget_data[0]; /* for the transport */
    /* starget_data must be the last element!!!! */
} __attribute__((aligned(sizeof(unsigned long))));

struct scatterlist {
    struct page        *page;
    unsigned int    offset;
    dma_addr_t        dma_address;
    unsigned int    length;
};

/* command block wrapper */
struct bulk_cb_wrap {
    __le32    Signature;        /* contains 'USBC' */
    __u32    Tag;            /* unique per command id */
    __le32    DataTransferLength;    /* size of data */
    __u8    Flags;            /* direction in bit 0 */
    __u8    Lun;            /* LUN normally 0 */
    __u8    Length;            /* of of the CDB */
    __u8    CDB[16];        /* max command */
};

#define US_BULK_CB_WRAP_LEN    31
#define US_BULK_CB_SIGN        0x43425355    /*spells out USBC */
#define US_BULK_FLAG_IN        1
#define US_BULK_FLAG_OUT    0

/* command status wrapper */
struct bulk_cs_wrap {
    __le32    Signature;        /* should = 'USBS' */
    __u32    Tag;            /* same as original command */
    __le32    Residue;        /* amount not transferred */
    __u8    Status;            /* see below */
    __u8    Filler[18];
};

struct us_unusual_dev {
    const char* vendorName;
    const char* productName;
    __u8  useProtocol;
    __u8  useTransport;
    int (*initFunction)(struct us_data *);
};

/* Dynamic flag definitions: used in set_bit() etc. */
#define US_FLIDX_URB_ACTIVE    18  /* 0x00040000  current_urb is in use  */
#define US_FLIDX_SG_ACTIVE    19  /* 0x00080000  current_sg is in use   */
#define US_FLIDX_ABORTING    20  /* 0x00100000  abort is in progress   */
#define US_FLIDX_DISCONNECTING    21  /* 0x00200000  disconnect in progress */
#define ABORTING_OR_DISCONNECTING    ((1UL << US_FLIDX_ABORTING) | \
                     (1UL << US_FLIDX_DISCONNECTING))
#define US_FLIDX_RESETTING    22  /* 0x00400000  device reset in progress */
#define US_FLIDX_TIMED_OUT    23  /* 0x00800000  SCSI midlayer timed out  */

#define USB_STOR_STRING_LEN 32

/*
 * We provide a DMA-mapped I/O buffer for use with small USB transfers.
 * It turns out that CB[I] needs a 12-byte buffer and Bulk-only needs a
 * 31-byte buffer.  But Freecom needs a 64-byte buffer, so that's the
 * size we'll allocate.
 */

#define US_IOBUF_SIZE        64    /* Size of the DMA-mapped I/O buffer */
#define US_SENSE_SIZE        18    /* Size of the autosense data buffer */

typedef int (*trans_cmnd)(struct scsi_cmnd *, struct us_data*);
typedef int (*trans_reset)(struct us_data*);
typedef void (*proto_cmnd)(struct scsi_cmnd*, struct us_data*);
typedef void (*extra_data_destructor)(void *);    /* extra data destructor */
typedef void (*pm_hook)(struct us_data *, int);    /* power management hook */

#define US_SUSPEND    0
#define US_RESUME    1

/* we allocate one of these for every device that we remember */
struct us_data {
    /* The device we're working with
     * It's important to note:
     *    (o) you must hold dev_mutex to change pusb_dev
     */
    struct mutex        dev_mutex;     /* protect pusb_dev */
    struct usb_device    *pusb_dev;     /* this usb_device */
    struct usb_interface    *pusb_intf;     /* this interface */
    struct us_unusual_dev   *unusual_dev;     /* device-filter entry     */
    unsigned long        flags;         /* from filter initially */
    unsigned int        send_bulk_pipe;     /* cached pipe values */
    unsigned int        recv_bulk_pipe;
    unsigned int        send_ctrl_pipe;
    unsigned int        recv_ctrl_pipe;
    unsigned int        recv_intr_pipe;

/* information about the device */
    char            *transport_name;
    char            *protocol_name;
    __le32            bcs_signature;
    u8            subclass;
    u8            protocol;
    u8            max_lun;

u8            ifnum;         /* interface number   */
    u8            ep_bInterval;     /* interrupt interval */

/* function pointers for this device */
    trans_cmnd        transport;     /* transport function       */
    trans_reset        transport_reset; /* transport device reset */
    proto_cmnd        proto_handler;     /* protocol handler       */

/* SCSI interfaces */
    struct scsi_cmnd    *srb;         /* current srb        */
    unsigned int        tag;         /* current dCBWTag    */

/* control and bulk communications data */
    struct urb        *current_urb;     /* USB requests     */
    struct usb_ctrlrequest    *cr;         /* control requests     */
    struct usb_sg_request    current_sg;     /* scatter-gather req.  */
    unsigned char        *iobuf;         /* I/O buffer         */
    unsigned char        *sensebuf;     /* sense data buffer     */
    dma_addr_t        cr_dma;         /* buffer DMA addresses */
    dma_addr_t        iobuf_dma;

/* mutual exclusion and synchronization structures */
    struct semaphore    sema;         /* to sleep thread on        */
    struct completion    notify;         /* thread begin/end        */
    wait_queue_head_t    delay_wait;     /* wait during scan, reset */

/* subdriver information */
    void            *extra;         /* Any extra data          */
    extra_data_destructor    extra_destructor;/* extra data destructor   */
#ifdef CONFIG_PM
    pm_hook            suspend_resume_hook;
#endif
};

struct scsi_host_template usb_stor_host_template = {
    /* basic userland interface stuff */
    .name =                "usb-storage",
    .proc_name =            "usb-storage",
    .proc_info =            proc_info,
    .info =                host_info,

/* command interface -- queued only */
    .queuecommand =            queuecommand,

/* error and abort handlers */
    .eh_abort_handler =        command_abort,
    .eh_device_reset_handler =    device_reset,
    .eh_bus_reset_handler =        bus_reset,

/* queue commands only, only one command per LUN */
    .can_queue =            1,
    .cmd_per_lun =            1,

/* unknown initiator id */
    .this_id =            -1,

.slave_alloc =            slave_alloc,
    .slave_configure =        slave_configure,

/* lots of sg segments can be handled */
    .sg_tablesize =            SG_ALL,

/* limit the total size of a transfer to 120 KB */
    .max_sectors =                  240,

/* merge commands... this seems to help performance, but
     * periodically someone should test to see which setting is more
     * optimal.
     */
    .use_clustering =        1,

/* emulated HBA */
    .emulated =            1,

/* we do our own delay after a device or bus reset */
    .skip_settle_delay =        1,

/* sysfs device attributes */
    .sdev_attrs =            sysfs_device_attr_list,

/* module management */
    .module =            THIS_MODULE
};

/* To Report "Illegal Request: Invalid Field in CDB */
unsigned char usb_stor_sense_invalidCDB[18] = {
    [0]    = 0x70,                /* current error */
    [2]    = ILLEGAL_REQUEST,        /* Illegal Request = 0x05 */
    [7]    = 0x0a,                /* additional length */
    [12]    = 0x24                /* Invalid Field in CDB */
};