USB Drivers 相关结构体和宏定义记录

USB Drivers 相关数据结构记录

struct usb_device_id

路径：include/linux/mod_devicetable.h

/**
 * struct usb_device_id - identifies USB devices for probing and hotplugging
 * @match_flags: Bit mask controlling of the other fields are used to match
 *	against new devices.  Any field except for driver_info may be used,
 *	although some only make sense in conjunction with other fields.
 *	This is usually set by a USB_DEVICE_*() macro, which sets all
 *	other fields in this structure except for driver_info.
 * @idVendor: USB vendor ID for a device; numbers are assigned
 *	by the USB forum to its members.
 * @idProduct: Vendor-assigned product ID.
 * @bcdDevice_lo: Low end of range of vendor-assigned product version numbers.
 *	This is also used to identify individual product versions, for
 *	a range consisting of a single device.
 * @bcdDevice_hi: High end of version number range.  The range of product
 *	versions is inclusive.
 * @bDeviceClass: Class of device; numbers are assigned
 *	by the USB forum.  Products may choose to implement classes,
 *	or be vendor-specific.  Device classes specify behavior of all
 *	the interfaces on a devices.
 * @bDeviceSubClass: Subclass of device; associated with bDeviceClass.
 * @bDeviceProtocol: Protocol of device; associated with bDeviceClass.
 * @bInterfaceClass: Class of interface; numbers are assigned
 *	by the USB forum.  Products may choose to implement classes,
 *	or be vendor-specific.  Interface classes specify behavior only
 *	of a given interface; other interfaces may support other classes.
 * @bInterfaceSubClass: Subclass of interface; associated with bInterfaceClass.
 * @bInterfaceProtocol: Protocol of interface; associated with bInterfaceClass.
 * @bInterfaceNumber: Number of interface; composite devices may use
 *	fixed interface numbers to differentiate between vendor-specific
 *	interfaces.
 * @driver_info: Holds information used by the driver.  Usually it holds
 *	a pointer to a descriptor understood by the driver, or perhaps
 *	device flags.
 *
 * In most cases, drivers will create a table of device IDs by using
 * USB_DEVICE(), or similar macros designed for that purpose.
 * They will then export it to userspace using MODULE_DEVICE_TABLE(),
 * and provide it to the USB core through their usb_driver structure.
 *
 * See the usb_match_id() function for information about how matches are
 * performed.  Briefly, you will normally use one of several macros to help
 * construct these entries.  Each entry you provide will either identify
 * one or more specific products, or will identify a class of products
 * which have agreed to behave the same.  You should put the more specific
 * matches towards the beginning of your table, so that driver_info can
 * record quirks of specific products.
 */
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;

	/* Used for vendor-specific interface matches */
	__u8		bInterfaceNumber;

	/* not matched against */
	kernel_ulong_t	driver_info
		__attribute__((aligned(sizeof(kernel_ulong_t))));
};

Macro:    USB_DEVICE

include/linux/usb.h

/**
 * USB_DEVICE - macro used to describe a specific usb device
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device.
 */
#define USB_DEVICE(vend, prod) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE, \
	.idVendor = (vend), \
	.idProduct = (prod)

Macro:  MODULE_DEVICE_TABLE

路径：include/linux/module.h

#define MODULE_DEVICE_TABLE(type,name)		\
  MODULE_GENERIC_TABLE(type##_device,name)

#define MODULE_GENERIC_TABLE(gtype,name)			\
extern const struct gtype##_id __mod_##gtype##_table		\
  __attribute__ ((unused, alias(__stringify(name))))

struct kref

路径： include/linux/kref.h

struct kref {
	atomic_t refcount;
};

struct urb

path: include/linux/usb.h

/**
 * struct urb - USB Request Block
 * @urb_list: For use by current owner of the URB.
 * @anchor_list: membership in the list of an anchor
 * @anchor: to anchor URBs to a common mooring
 * @ep: Points to the endpoint's data structure.  Will eventually
 *	replace @pipe.
 * @pipe: Holds endpoint number, direction, type, and more.
 *	Create these values with the eight macros available;
 *	usb_{snd,rcv}TYPEpipe(dev,endpoint), where the TYPE is "ctrl"
 *	(control), "bulk", "int" (interrupt), or "iso" (isochronous).
 *	For example usb_sndbulkpipe() or usb_rcvintpipe().  Endpoint
 *	numbers range from zero to fifteen.  Note that "in" endpoint two
 *	is a different endpoint (and pipe) from "out" endpoint two.
 *	The current configuration controls the existence, type, and
 *	maximum packet size of any given endpoint.
 * @stream_id: the endpoint's stream ID for bulk streams
 * @dev: Identifies the USB device to perform the request.
 * @status: This is read in non-iso completion functions to get the
 *	status of the particular request.  ISO requests only use it
 *	to tell whether the URB was unlinked; detailed status for
 *	each frame is in the fields of the iso_frame-desc.
 * @transfer_flags: A variety of flags may be used to affect how URB
 *	submission, unlinking, or operation are handled.  Different
 *	kinds of URB can use different flags.
 * @transfer_buffer:  This identifies the buffer to (or from) which the I/O
 *	request will be performed unless URB_NO_TRANSFER_DMA_MAP is set
 *	(however, do not leave garbage in transfer_buffer even then).
 *	This buffer must be suitable for DMA; allocate it with
 *	kmalloc() or equivalent.  For transfers to "in" endpoints, contents
 *	of this buffer will be modified.  This buffer is used for the data
 *	stage of control transfers.
 * @transfer_dma: When transfer_flags includes URB_NO_TRANSFER_DMA_MAP,
 *	the device driver is saying that it provided this DMA address,
 *	which the host controller driver should use in preference to the
 *	transfer_buffer.
 * @sg: scatter gather buffer list, the buffer size of each element in
 * 	the list (except the last) must be divisible by the endpoint's
 * 	max packet size if no_sg_constraint isn't set in 'struct usb_bus'
 * 	(FIXME: scatter-gather under xHCI is broken for periodic transfers.
 * 	Do not use urb->sg for interrupt endpoints for now, only bulk.)
 * @num_mapped_sgs: (internal) number of mapped sg entries
 * @num_sgs: number of entries in the sg list
 * @transfer_buffer_length: How big is transfer_buffer.  The transfer may
 *	be broken up into chunks according to the current maximum packet
 *	size for the endpoint, which is a function of the configuration
 *	and is encoded in the pipe.  When the length is zero, neither
 *	transfer_buffer nor transfer_dma is used.
 * @actual_length: This is read in non-iso completion functions, and
 *	it tells how many bytes (out of transfer_buffer_length) were
 *	transferred.  It will normally be the same as requested, unless
 *	either an error was reported or a short read was performed.
 *	The URB_SHORT_NOT_OK transfer flag may be used to make such
 *	short reads be reported as errors.
 * @setup_packet: Only used for control transfers, this points to eight bytes
 *	of setup data.  Control transfers always start by sending this data
 *	to the device.  Then transfer_buffer is read or written, if needed.
 * @setup_dma: DMA pointer for the setup packet.  The caller must not use
 *	this field; setup_packet must point to a valid buffer.
 * @start_frame: Returns the initial frame for isochronous transfers.
 * @number_of_packets: Lists the number of ISO transfer buffers.
 * @interval: Specifies the polling interval for interrupt or isochronous
 *	transfers.  The units are frames (milliseconds) for full and low
 *	speed devices, and microframes (1/8 millisecond) for highspeed
 *	and SuperSpeed devices.
 * @error_count: Returns the number of ISO transfers that reported errors.
 * @context: For use in completion functions.  This normally points to
 *	request-specific driver context.
 * @complete: Completion handler. This URB is passed as the parameter to the
 *	completion function.  The completion function may then do what
 *	it likes with the URB, including resubmitting or freeing it.
 * @iso_frame_desc: Used to provide arrays of ISO transfer buffers and to
 *	collect the transfer status for each buffer.
 *
 * This structure identifies USB transfer requests.  URBs must be allocated by
 * calling usb_alloc_urb() and freed with a call to usb_free_urb().
 * Initialization may be done using various usb_fill_*_urb() functions.  URBs
 * are submitted using usb_submit_urb(), and pending requests may be canceled
 * using usb_unlink_urb() or usb_kill_urb().
 *
 * Data Transfer Buffers:
 *
 * Normally drivers provide I/O buffers allocated with kmalloc() or otherwise
 * taken from the general page pool.  That is provided by transfer_buffer
 * (control requests also use setup_packet), and host controller drivers
 * perform a dma mapping (and unmapping) for each buffer transferred.  Those
 * mapping operations can be expensive on some platforms (perhaps using a dma
 * bounce buffer or talking to an IOMMU),
 * although they're cheap on commodity x86 and ppc hardware.
 *
 * Alternatively, drivers may pass the URB_NO_TRANSFER_DMA_MAP transfer flag,
 * which tells the host controller driver that no such mapping is needed for
 * the transfer_buffer since
 * the device driver is DMA-aware.  For example, a device driver might
 * allocate a DMA buffer with usb_alloc_coherent() or call usb_buffer_map().
 * When this transfer flag is provided, host controller drivers will
 * attempt to use the dma address found in the transfer_dma
 * field rather than determining a dma address themselves.
 *
 * Note that transfer_buffer must still be set if the controller
 * does not support DMA (as indicated by bus.uses_dma) and when talking
 * to root hub. If you have to trasfer between highmem zone and the device
 * on such controller, create a bounce buffer or bail out with an error.
 * If transfer_buffer cannot be set (is in highmem) and the controller is DMA
 * capable, assign NULL to it, so that usbmon knows not to use the value.
 * The setup_packet must always be set, so it cannot be located in highmem.
 *
 * Initialization:
 *
 * All URBs submitted must initialize the dev, pipe, transfer_flags (may be
 * zero), and complete fields.  All URBs must also initialize
 * transfer_buffer and transfer_buffer_length.  They may provide the
 * URB_SHORT_NOT_OK transfer flag, indicating that short reads are
 * to be treated as errors; that flag is invalid for write requests.
 *
 * Bulk URBs may
 * use the URB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
 * should always terminate with a short packet, even if it means adding an
 * extra zero length packet.
 *
 * Control URBs must provide a valid pointer in the setup_packet field.
 * Unlike the transfer_buffer, the setup_packet may not be mapped for DMA
 * beforehand.
 *
 * Interrupt URBs must provide an interval, saying how often (in milliseconds
 * or, for highspeed devices, 125 microsecond units)
 * to poll for transfers.  After the URB has been submitted, the interval
 * field reflects how the transfer was actually scheduled.
 * The polling interval may be more frequent than requested.
 * For example, some controllers have a maximum interval of 32 milliseconds,
 * while others support intervals of up to 1024 milliseconds.
 * Isochronous URBs also have transfer intervals.  (Note that for isochronous
 * endpoints, as well as high speed interrupt endpoints, the encoding of
 * the transfer interval in the endpoint descriptor is logarithmic.
 * Device drivers must convert that value to linear units themselves.)
 *
 * If an isochronous endpoint queue isn't already running, the host
 * controller will schedule a new URB to start as soon as bandwidth
 * utilization allows.  If the queue is running then a new URB will be
 * scheduled to start in the first transfer slot following the end of the
 * preceding URB, if that slot has not already expired.  If the slot has
 * expired (which can happen when IRQ delivery is delayed for a long time),
 * the scheduling behavior depends on the URB_ISO_ASAP flag.  If the flag
 * is clear then the URB will be scheduled to start in the expired slot,
 * implying that some of its packets will not be transferred; if the flag
 * is set then the URB will be scheduled in the first unexpired slot,
 * breaking the queue's synchronization.  Upon URB completion, the
 * start_frame field will be set to the (micro)frame number in which the
 * transfer was scheduled.  Ranges for frame counter values are HC-specific
 * and can go from as low as 256 to as high as 65536 frames.
 *
 * Isochronous URBs have a different data transfer model, in part because
 * the quality of service is only "best effort".  Callers provide specially
 * allocated URBs, with number_of_packets worth of iso_frame_desc structures
 * at the end.  Each such packet is an individual ISO transfer.  Isochronous
 * URBs are normally queued, submitted by drivers to arrange that
 * transfers are at least double buffered, and then explicitly resubmitted
 * in completion handlers, so
 * that data (such as audio or video) streams at as constant a rate as the
 * host controller scheduler can support.
 *
 * Completion Callbacks:
 *
 * The completion callback is made in_interrupt(), and one of the first
 * things that a completion handler should do is check the status field.
 * The status field is provided for all URBs.  It is used to report
 * unlinked URBs, and status for all non-ISO transfers.  It should not
 * be examined before the URB is returned to the completion handler.
 *
 * The context field is normally used to link URBs back to the relevant
 * driver or request state.
 *
 * When the completion callback is invoked for non-isochronous URBs, the
 * actual_length field tells how many bytes were transferred.  This field
 * is updated even when the URB terminated with an error or was unlinked.
 *
 * ISO transfer status is reported in the status and actual_length fields
 * of the iso_frame_desc array, and the number of errors is reported in
 * error_count.  Completion callbacks for ISO transfers will normally
 * (re)submit URBs to ensure a constant transfer rate.
 *
 * Note that even fields marked "public" should not be touched by the driver
 * when the urb is owned by the hcd, that is, since the call to
 * usb_submit_urb() till the entry into the completion routine.
 */
struct urb {
	/* private: usb core and host controller only fields in the urb */
	struct kref kref;		/* reference count of the URB */
	void *hcpriv;			/* private data for host controller */
	atomic_t use_count;		/* concurrent submissions counter */
	atomic_t reject;		/* submissions will fail */
	int unlinked;			/* unlink error code */

	/* 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 list_head anchor_list;	/* the URB may be anchored */
	struct usb_anchor *anchor;
	struct usb_device *dev;		/* (in) pointer to associated device */
	struct usb_host_endpoint *ep;	/* (internal) pointer to endpoint */
	unsigned int pipe;		/* (in) pipe information */
	unsigned int stream_id;		/* (in) stream ID */
	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 */
	struct scatterlist *sg;		/* (in) scatter gather buffer list */
	int num_mapped_sgs;		/* (internal) mapped sg entries */
	int num_sgs;			/* (in) number of entries in the sg list */
	u32 transfer_buffer_length;	/* (in) data buffer length */
	u32 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 usb_interface

path: include/linux/usb.h

/**
 * struct usb_interface - what usb device drivers talk to
 * @altsetting: array of interface structures, one for each alternate
 *	setting that may be selected.  Each one includes a set of
 *	endpoint configurations.  They will be in no particular order.
 * @cur_altsetting: the current altsetting.
 * @num_altsetting: number of altsettings defined.
 * @intf_assoc: interface association descriptor
 * @minor: the minor number assigned to this interface, if this
 *	interface is bound to a driver that uses the USB major number.
 *	If this interface does not use the USB major, this field should
 *	be unused.  The driver should set this value in the probe()
 *	function of the driver, after it has been assigned a minor
 *	number from the USB core by calling usb_register_dev().
 * @condition: binding state of the interface: not bound, binding
 *	(in probe()), bound to a driver, or unbinding (in disconnect())
 * @sysfs_files_created: sysfs attributes exist
 * @ep_devs_created: endpoint child pseudo-devices exist
 * @unregistering: flag set when the interface is being unregistered
 * @needs_remote_wakeup: flag set when the driver requires remote-wakeup
 *	capability during autosuspend.
 * @needs_altsetting0: flag set when a set-interface request for altsetting 0
 *	has been deferred.
 * @needs_binding: flag set when the driver should be re-probed or unbound
 *	following a reset or suspend operation it doesn't support.
 * @dev: driver model's view of this device
 * @usb_dev: if an interface is bound to the USB major, this will point
 *	to the sysfs representation for that device.
 * @pm_usage_cnt: PM usage counter for this interface
 * @reset_ws: Used for scheduling resets from atomic context.
 * @reset_running: set to 1 if the interface is currently running a
 *      queued reset so that usb_cancel_queued_reset() doesn't try to
 *      remove from the workqueue when running inside the worker
 *      thread. See __usb_queue_reset_device().
 * @resetting_device: USB core reset the device, so use alt setting 0 as
 *	current; needs bandwidth alloc after reset.
 *
 * USB device drivers attach to interfaces on a physical device.  Each
 * interface encapsulates a single high level function, such as feeding
 * an audio stream to a speaker or reporting a change in a volume control.
 * Many USB devices only have one interface.  The protocol used to talk to
 * an interface's endpoints can be defined in a usb "class" specification,
 * or by a product's vendor.  The (default) control endpoint is part of
 * every interface, but is never listed among the interface's descriptors.
 *
 * The driver that is bound to the interface can use standard driver model
 * calls such as dev_get_drvdata() on the dev member of this structure.
 *
 * Each interface may have alternate settings.  The initial configuration
 * of a device sets altsetting 0, but the device driver can change
 * that setting using usb_set_interface().  Alternate settings are often
 * used to control the use of periodic endpoints, such as by having
 * different endpoints use different amounts of reserved USB bandwidth.
 * All standards-conformant USB devices that use isochronous endpoints
 * will use them in non-default settings.
 *
 * The USB specification says that alternate setting numbers must run from
 * 0 to one less than the total number of alternate settings.  But some
 * devices manage to mess this up, and the structures aren't necessarily
 * stored in numerical order anyhow.  Use usb_altnum_to_altsetting() to
 * look up an alternate setting in the altsetting array based on its number.
 */
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 */

	/* If there is an interface association descriptor then it will list
	 * the associated interfaces */
	struct usb_interface_assoc_descriptor *intf_assoc;

	int minor;			/* minor number this interface is
					 * bound to */
	enum usb_interface_condition condition;		/* state of binding */
	unsigned sysfs_files_created:1;	/* the sysfs attributes exist */
	unsigned ep_devs_created:1;	/* endpoint "devices" exist */
	unsigned unregistering:1;	/* unregistration is in progress */
	unsigned needs_remote_wakeup:1;	/* driver requires remote wakeup */
	unsigned needs_altsetting0:1;	/* switch to altsetting 0 is pending */
	unsigned needs_binding:1;	/* needs delayed unbind/rebind */
	unsigned reset_running:1;
	unsigned resetting_device:1;	/* true: bandwidth alloc after reset */

	struct device dev;		/* interface specific device info */
	struct device *usb_dev;
	atomic_t pm_usage_cnt;		/* usage counter for autosuspend */
	struct work_struct reset_ws;	/* for resets in atomic context */
};

struct usb_device

path: include/linux/usb.h

/**
 * struct usb_device - kernel's representation of a USB device
 * @devnum: device number; address on a USB bus
 * @devpath: device ID string for use in messages (e.g., /port/...)
 * @route: tree topology hex string for use with xHCI
 * @state: device state: configured, not attached, etc.
 * @speed: device speed: high/full/low (or error)
 * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
 * @ttport: device port on that tt hub
 * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
 * @parent: our hub, unless we're the root
 * @bus: bus we're part of
 * @ep0: endpoint 0 data (default control pipe)
 * @dev: generic device interface
 * @descriptor: USB device descriptor
 * @bos: USB device BOS descriptor set
 * @config: all of the device's configs
 * @actconfig: the active configuration
 * @ep_in: array of IN endpoints
 * @ep_out: array of OUT endpoints
 * @rawdescriptors: raw descriptors for each config
 * @bus_mA: Current available from the bus
 * @portnum: parent port number (origin 1)
 * @level: number of USB hub ancestors
 * @can_submit: URBs may be submitted
 * @persist_enabled:  USB_PERSIST enabled for this device
 * @have_langid: whether string_langid is valid
 * @authorized: policy has said we can use it;
 *	(user space) policy determines if we authorize this device to be
 *	used or not. By default, wired USB devices are authorized.
 *	WUSB devices are not, until we authorize them from user space.
 *	FIXME -- complete doc
 * @authenticated: Crypto authentication passed
 * @wusb: device is Wireless USB
 * @lpm_capable: device supports LPM
 * @usb2_hw_lpm_capable: device can perform USB2 hardware LPM
 * @usb2_hw_lpm_besl_capable: device can perform USB2 hardware BESL LPM
 * @usb2_hw_lpm_enabled: USB2 hardware LPM is enabled
 * @usb2_hw_lpm_allowed: Userspace allows USB 2.0 LPM to be enabled
 * @usb3_lpm_enabled: USB3 hardware LPM enabled
 * @string_langid: language ID for strings
 * @product: iProduct string, if present (static)
 * @manufacturer: iManufacturer string, if present (static)
 * @serial: iSerialNumber string, if present (static)
 * @filelist: usbfs files that are open to this device
 * @maxchild: number of ports if hub
 * @quirks: quirks of the whole device
 * @urbnum: number of URBs submitted for the whole device
 * @active_duration: total time device is not suspended
 * @connect_time: time device was first connected
 * @do_remote_wakeup:  remote wakeup should be enabled
 * @reset_resume: needs reset instead of resume
 * @port_is_suspended: the upstream port is suspended (L2 or U3)
 * @wusb_dev: if this is a Wireless USB device, link to the WUSB
 *	specific data for the device.
 * @slot_id: Slot ID assigned by xHCI
 * @removable: Device can be physically removed from this port
 * @l1_params: best effor service latency for USB2 L1 LPM state, and L1 timeout.
 * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout.
 * @u2_params: exit latencies for USB3 U2 LPM state, and hub-initiated timeout.
 * @lpm_disable_count: Ref count used by usb_disable_lpm() and usb_enable_lpm()
 *	to keep track of the number of functions that require USB 3.0 Link Power
 *	Management to be disabled for this usb_device.  This count should only
 *	be manipulated by those functions, with the bandwidth_mutex is held.
 *
 * Notes:
 * Usbcore drivers should not set usbdev->state directly.  Instead use
 * usb_set_device_state().
 */
struct usb_device {
	int		devnum;
	char		devpath[16];
	u32		route;
	enum usb_device_state	state;
	enum usb_device_speed	speed;

	struct usb_tt	*tt;
	int		ttport;

	unsigned int toggle[2];

	struct usb_device *parent;
	struct usb_bus *bus;
	struct usb_host_endpoint ep0;

	struct device dev;

	struct usb_device_descriptor descriptor;
	struct usb_host_bos *bos;
	struct usb_host_config *config;

	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;

	unsigned can_submit:1;
	unsigned persist_enabled:1;
	unsigned have_langid:1;
	unsigned authorized:1;
	unsigned authenticated:1;
	unsigned wusb:1;
	unsigned lpm_capable:1;
	unsigned usb2_hw_lpm_capable:1;
	unsigned usb2_hw_lpm_besl_capable:1;
	unsigned usb2_hw_lpm_enabled:1;
	unsigned usb2_hw_lpm_allowed:1;
	unsigned usb3_lpm_enabled:1;
	int string_langid;

	/* static strings from the device */
	char *product;
	char *manufacturer;
	char *serial;

	struct list_head filelist;

	int maxchild;

	u32 quirks;
	atomic_t urbnum;

	unsigned long active_duration;

#ifdef CONFIG_PM
	unsigned long connect_time;

	unsigned do_remote_wakeup:1;
	unsigned reset_resume:1;
	unsigned port_is_suspended:1;
#endif
	struct wusb_dev *wusb_dev;
	int slot_id;
	enum usb_device_removable removable;
	struct usb2_lpm_parameters l1_params;
	struct usb3_lpm_parameters u1_params;
	struct usb3_lpm_parameters u2_params;
	unsigned lpm_disable_count;
};

struct usb_host_config

path: include/linux/usb.h

/**
 * struct usb_host_config - representation of a device's configuration
 * @desc: the device's configuration descriptor.
 * @string: pointer to the cached version of the iConfiguration string, if
 *	present for this configuration.
 * @intf_assoc: list of any interface association descriptors in this config
 * @interface: array of pointers to usb_interface structures, one for each
 *	interface in the configuration.  The number of interfaces is stored
 *	in desc.bNumInterfaces.  These pointers are valid only while the
 *	the configuration is active.
 * @intf_cache: array of pointers to usb_interface_cache structures, one
 *	for each interface in the configuration.  These structures exist
 *	for the entire life of the device.
 * @extra: pointer to buffer containing all extra descriptors associated
 *	with this configuration (those preceding the first interface
 *	descriptor).
 * @extralen: length of the extra descriptors buffer.
 *
 * USB devices may have multiple configurations, but only one can be active
 * at any time.  Each encapsulates a different operational environment;
 * for example, a dual-speed device would have separate configurations for
 * full-speed and high-speed operation.  The number of configurations
 * available is stored in the device descriptor as bNumConfigurations.
 *
 * A configuration can contain multiple interfaces.  Each corresponds to
 * a different function of the USB device, and all are available whenever
 * the configuration is active.  The USB standard says that interfaces
 * are supposed to be numbered from 0 to desc.bNumInterfaces-1, but a lot
 * of devices get this wrong.  In addition, the interface array is not
 * guaranteed to be sorted in numerical order.  Use usb_ifnum_to_if() to
 * look up an interface entry based on its number.
 *
 * Device drivers should not attempt to activate configurations.  The choice
 * of which configuration to install is a policy decision based on such
 * considerations as available power, functionality provided, and the user's
 * desires (expressed through userspace tools).  However, drivers can call
 * usb_reset_configuration() to reinitialize the current configuration and
 * all its interfaces.
 */
struct usb_host_config {
	struct usb_config_descriptor	desc;

	char *string;		/* iConfiguration string, if present */

	/* List of any Interface Association Descriptors in this
	 * configuration. */
	struct usb_interface_assoc_descriptor *intf_assoc[USB_MAXIADS];

	/* 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;
};

函数iminor imajor

path :include/linux/fs.h

static inline unsigned iminor(const struct inode *inode)
{
	return MINOR(inode->i_rdev);
}

static inline unsigned imajor(const struct inode *inode)
{
	return MAJOR(inode->i_rdev);
}

struct usb_class_driver

usb.h

/**
 * struct usb_class_driver - identifies a USB driver that wants to use the USB major number
 * @name: the usb class device name for this driver.  Will show up in sysfs.
 * @devnode: Callback to provide a naming hint for a possible
 *	device node to create.
 * @fops: pointer to the struct file_operations of this driver.
 * @minor_base: the start of the minor range for this driver.
 *
 * This structure is used for the usb_register_dev() and
 * usb_unregister_dev() functions, to consolidate a number of the
 * parameters used for them.
 */
struct usb_class_driver {
	char *name;
	char *(*devnode)(struct device *dev, umode_t *mode);
	const struct file_operations *fops;
	int minor_base;
};

struct usb_host_endpoint

/**
 * struct usb_host_endpoint - host-side endpoint descriptor and queue
 * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
 * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint
 * @urb_list: urbs queued to this endpoint; maintained by usbcore
 * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)
 *	with one or more transfer descriptors (TDs) per urb
 * @ep_dev: ep_device for sysfs info
 * @extra: descriptors following this endpoint in the configuration
 * @extralen: how many bytes of "extra" are valid
 * @enabled: URBs may be submitted to this endpoint
 *
 * USB requests are always queued to a given endpoint, identified by a
 * descriptor within an active interface in a given USB configuration.
 */
struct usb_host_endpoint {
	struct usb_endpoint_descriptor		desc;
	struct usb_ss_ep_comp_descriptor	ss_ep_comp;
	struct list_head		urb_list;
	void				*hcpriv;
	struct ep_device		*ep_dev;	/* For sysfs info */


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

struct usb_host_interface

/* host-side wrapper for one interface setting's parsed descriptors */
struct usb_host_interface {
	struct usb_interface_descriptor	desc;


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


	/* 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 */
};

struct usb_device_descriptor

/* USB_DT_DEVICE: Device descriptor */
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));

USB设备类型宏定义

/*
 * Device and/or Interface Class codes
 * as found in bDeviceClass or bInterfaceClass
 * and defined by www.usb.org documents
 */
#define USB_CLASS_PER_INTERFACE		0	/* for DeviceClass */
#define USB_CLASS_AUDIO			1
#define USB_CLASS_COMM			2
#define USB_CLASS_HID			        3
#define USB_CLASS_PHYSICAL		5
#define USB_CLASS_STILL_IMAGE	6
#define USB_CLASS_PRINTER		7
#define USB_CLASS_MASS_STORAGE	8
#define USB_CLASS_HUB			9
#define USB_CLASS_CDC_DATA		0x0a
#define USB_CLASS_CSCID			0x0b	/* chip+ smart card */
#define USB_CLASS_CONTENT_SEC	0x0d	/* content security */
#define USB_CLASS_VIDEO			0x0e
#define USB_CLASS_WIRELESS_CONTROLLER	0xe0
#define USB_CLASS_MISC			0xef
#define USB_CLASS_APP_SPEC		0xfe
#define USB_CLASS_VENDOR_SPEC	0xff


#define USB_SUBCLASS_VENDOR_SPEC	0xff

 

struct usb_config_descriptor

/* USB_DT_CONFIG: Configuration descriptor information.
 *
 * USB_DT_OTHER_SPEED_CONFIG is the same descriptor, except that the
 * descriptor type is different.  Highspeed-capable devices can look
 * different depending on what speed they're currently running.  Only
 * devices with a USB_DT_DEVICE_QUALIFIER have any OTHER_SPEED_CONFIG
 * descriptors.
 */
struct usb_config_descriptor {
	__u8  bLength;
	__u8  bDescriptorType;


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

struct usb_interface_descriptor

/* USB_DT_INTERFACE: Interface descriptor */
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_ss_ep_comp_descriptor

/* USB_DT_SS_ENDPOINT_COMP: SuperSpeed Endpoint Companion descriptor */
struct usb_ss_ep_comp_descriptor {
	__u8  bLength;
	__u8  bDescriptorType;

	__u8  bMaxBurst;
	__u8  bmAttributes;
	__le16 wBytesPerInterval;
} __attribute__ ((packed));

函数： usb_get_dev

path : drivers/usb/core/usb.c

/**
 * usb_get_dev - increments the reference count of the usb device structure
 * @dev: the device being referenced
 *
 * Each live reference to a device should be refcounted.
 *
 * Drivers for USB interfaces should normally record such references in
 * their probe() methods, when they bind to an interface, and release
 * them by calling usb_put_dev(), in their disconnect() methods.
 *
 * Return: A pointer to the device with the incremented reference counter.
 */
struct usb_device *usb_get_dev(struct usb_device *dev)
{
	if (dev)
		get_device(&dev->dev);
	return dev;
}
EXPORT_SYMBOL_GPL(usb_get_dev);

函数： usb_put_dev

path : drivers/usb/core/usb.c

/**
 * usb_put_dev - release a use of the usb device structure
 * @dev: device that's been disconnected
 *
 * Must be called when a user of a device is finished with it.  When the last
 * user of the device calls this function, the memory of the device is freed.
 */
void usb_put_dev(struct usb_device *dev)
{
	if (dev)
		put_device(&dev->dev);
}
EXPORT_SYMBOL_GPL(usb_put_dev);

dev_get_drvdata

path :drivers/base/dd.c

/*
 * These exports can't be _GPL due to .h files using this within them, and it
 * might break something that was previously working...
 */
void *dev_get_drvdata(const struct device *dev)
{
	if (dev && dev->p)
		return dev->p->driver_data;
	return NULL;
}
EXPORT_SYMBOL(dev_get_drvdata);

dev_set_drvdata

path :drivers/base/dd.c

int dev_set_drvdata(struct device *dev, void *data)
{
	int error;


	if (!dev->p) {
		error = device_private_init(dev);
		if (error)
			return error;
	}
	dev->p->driver_data = data;
	return 0;
}
EXPORT_SYMBOL(dev_set_drvdata);