usb.h

blackfin 的 usb devise 的代码 很基础

 */
#define USB_INTERFACE_INFO(cl,sc,pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO, .bInterfaceClass = (cl), \
	.bInterfaceSubClass = (sc), .bInterfaceProtocol = (pr)

/* ----------------------------------------------------------------------- */



/**
 * struct usb_driver - identifies USB interface driver to usbcore
 * @name: The driver name should be unique among USB drivers,
 *	and should normally be the same as the module name.
 * @probe: Called to see if the driver is willing to manage a particular
 *	interface on a device.  If it is, probe returns zero and uses
 *	dev_set_drvdata() to associate driver-specific data with the
 *	interface.  It may also use usb_set_interface() to specify the
 *	appropriate altsetting.  If unwilling to manage the interface,
 *	return a negative errno value.
 * @disconnect: Called when the interface is no longer accessible, usually
 *	because its device has been (or is being) disconnected or the
 *	driver module is being unloaded.
 * @ioctl: Used for drivers that want to talk to userspace through
 *	the "usbfs" filesystem.  This lets devices provide ways to
 *	expose information to user space regardless of where they
 *	do (or don't) show up otherwise in the filesystem.
 * @suspend: Called when the device is going to be suspended by the system.
 * @resume: Called when the device is being resumed by the system.
 * @pre_reset: Called by usb_reset_composite_device() when the device
 *	is about to be reset.
 * @post_reset: Called by usb_reset_composite_device() after the device
 *	has been reset.
 * @id_table: USB drivers use ID table to support hotplugging.
 *	Export this with MODULE_DEVICE_TABLE(usb,...).  This must be set
 *	or your driver's probe function will never get called.
 * @dynids: used internally to hold the list of dynamically added device
 *	ids for this driver.
 * @drvwrap: Driver-model core structure wrapper.
 * @no_dynamic_id: if set to 1, the USB core will not allow dynamic ids to be
 *	added to this driver by preventing the sysfs file from being created.
 * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
 *	for interfaces bound to this driver.
 *
 * USB interface drivers must provide a name, probe() and disconnect()
 * methods, and an id_table.  Other driver fields are optional.
 *
 * The id_table is used in hotplugging.  It holds a set of descriptors,
 * and specialized data may be associated with each entry.  That table
 * is used by both user and kernel mode hotplugging support.
 *
 * The probe() and disconnect() methods are called in a context where
 * they can sleep, but they should avoid abusing the privilege.  Most
 * work to connect to a device should be done when the device is opened,
 * and undone at the last close.  The disconnect code needs to address
 * concurrency issues with respect to open() and close() methods, as
 * well as forcing all pending I/O requests to complete (by unlinking
 * them as necessary, and blocking until the unlinks complete).
 */
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;
};
#define	to_usb_driver(d) container_of(d, struct usb_driver, drvwrap.driver)

/**
 * struct usb_device_driver - identifies USB device driver to usbcore
 * @name: The driver name should be unique among USB drivers,
 *	and should normally be the same as the module name.
 * @probe: Called to see if the driver is willing to manage a particular
 *	device.  If it is, probe returns zero and uses dev_set_drvdata()
 *	to associate driver-specific data with the device.  If unwilling
 *	to manage the device, return a negative errno value.
 * @disconnect: Called when the device is no longer accessible, usually
 *	because it has been (or is being) disconnected or the driver's
 *	module is being unloaded.
 * @suspend: Called when the device is going to be suspended by the system.
 * @resume: Called when the device is being resumed by the system.
 * @drvwrap: Driver-model core structure wrapper.
 * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
 *	for devices bound to this driver.
 *
 * USB drivers must provide all the fields listed above except drvwrap.
 */
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;
};
#define	to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
		drvwrap.driver)

extern struct bus_type usb_bus_type;

/**
 * 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.
 * @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;
	const struct file_operations *fops;
	int minor_base;
};

/*
 * use these in module_init()/module_exit()
 * and don't forget MODULE_DEVICE_TABLE(usb, ...)
 */
extern int usb_register_driver(struct usb_driver *, struct module *);
static inline int usb_register(struct usb_driver *driver)
{
///	return usb_register_driver(driver, THIS_MODULE);
}
extern void usb_deregister(struct usb_driver *);

extern int usb_register_device_driver(struct usb_device_driver *,
			struct module *);
extern void usb_deregister_device_driver(struct usb_device_driver *);

extern int usb_register_dev(struct usb_interface *intf,
			    struct usb_class_driver *class_driver);
extern void usb_deregister_dev(struct usb_interface *intf,
			       struct usb_class_driver *class_driver);

extern int usb_disabled(void);

/* ----------------------------------------------------------------------- */

/*
 * URB support, for asynchronous request completions
 */

/*
 * urb->transfer_flags:
 */
#define URB_SHORT_NOT_OK	0x0001	/* report short reads as errors */
#define URB_ISO_ASAP		0x0002	/* iso-only, urb->start_frame
					 * ignored */
#define URB_NO_TRANSFER_DMA_MAP	0x0004	/* urb->transfer_dma valid on submit */
#define URB_NO_SETUP_DMA_MAP	0x0008	/* urb->setup_dma valid on submit */
#define URB_NO_FSBR		0x0020	/* UHCI-specific */
#define URB_ZERO_PACKET		0x0040	/* Finish bulk OUT with short packet */
#define URB_NO_INTERRUPT	0x0080	/* HINT: no non-error interrupt
					 * needed */

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

struct urb;

typedef void (*usb_complete_t)(struct urb *);

/**
 * struct urb - USB Request Block
 * @urb_list: For use by current owner of the URB.
 * @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.
 * @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).  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.
 * @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: For control transfers with URB_NO_SETUP_DMA_MAP set, the
 *	device driver has provided this DMA address for the setup packet.
 *	The host controller driver should use this in preference to
 *	setup_packet.
 * @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 for full and low
 *	speed devices, and microframes (1/8 millisecond) for highspeed ones.
 * @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_xxx_DMA_MAP transfer flags,
 * which tell the host controller driver that no such mapping is needed since
 * the device driver is DMA-aware.  For example, a device driver might
 * allocate a DMA buffer with usb_buffer_alloc() or call usb_buffer_map().
 * When these transfer flags are provided, host controller drivers will
 * attempt to use the dma addresses found in the transfer_dma and/or
 * setup_dma fields rather than determining a dma address themselves.  (Note
 * that transfer_buffer and setup_packet must still be set because not all
 * host controllers use DMA, nor do virtual root hubs).
 *
 * 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 setup_packet.  The setup_packet and
 * transfer_buffer may each be mapped for DMA or not, independently of
 * the other.  The transfer_flags bits URB_NO_TRANSFER_DMA_MAP and
 * URB_NO_SETUP_DMA_MAP indicate which buffers have already been mapped.
 * URB_NO_SETUP_DMA_MAP is ignored for non-control URBs.
 *
 * 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.)
 *
 * Isochronous URBs normally use the URB_ISO_ASAP transfer flag, telling
 * the host controller to schedule the transfer as soon as bandwidth
 * utilization allows, and then set start_frame to reflect the actual frame
 * selected during submission.  Otherwise drivers must specify the start_frame
 * and handle the case where the transfer can't begin then.  However, drivers
 * won't know how bandwidth is currently allocated, and while they can
 * find the current frame using usb_get_current_frame_number () they can't
 * know the range for that frame number.  (Ranges for frame counter values
 * are HC-specific, and can go from 256 to 65536 frames from "now".)
 *
 * 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 */
	spinlock_t lock;		/* lock for the URB */
	void *hcpriv;			/* private data for host controller */