usb.h

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#ifndef __LINUX_USB_H
#define __LINUX_USB_H

#include <linux/mod_devicetable.h>
#include <linux/usb_ch9.h>

#define USB_MAJOR			180
#define USB_DEVICE_MAJOR		189


#ifdef __KERNEL__

#include <linux/config.h>
#include <linux/errno.h>        /* for -ENODEV */
#include <linux/delay.h>	/* for mdelay() */
#include <linux/interrupt.h>	/* for in_interrupt() */
#include <linux/list.h>		/* for struct list_head */
#include <linux/kref.h>		/* for struct kref */
#include <linux/device.h>	/* for struct device */
#include <linux/fs.h>		/* for struct file_operations */
#include <linux/completion.h>	/* for struct completion */
#include <linux/sched.h>	/* for current && schedule_timeout */

struct usb_device;
struct usb_driver;

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

/*
 * Host-side wrappers for standard USB descriptors ... these are parsed
 * from the data provided by devices.  Parsing turns them from a flat
 * sequence of descriptors into a hierarchy:
 *
 *  - devices have one (usually) or more configs;
 *  - configs have one (often) or more interfaces;
 *  - interfaces have one (usually) or more settings;
 *  - each interface setting has zero or (usually) more endpoints.
 *
 * And there might be other descriptors mixed in with those.
 *
 * Devices may also have class-specific or vendor-specific descriptors.
 */

/**
 * struct usb_host_endpoint - host-side endpoint descriptor and queue
 * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
 * @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
 * @extra: descriptors following this endpoint in the configuration
 * @extralen: how many bytes of "extra" are valid
 *
 * 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 list_head		urb_list;
	void				*hcpriv;

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

/* host-side wrapper for one interface setting's parsed descriptors */
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;
};

enum usb_interface_condition {
	USB_INTERFACE_UNBOUND = 0,
	USB_INTERFACE_BINDING,
	USB_INTERFACE_BOUND,
	USB_INTERFACE_UNBINDING,
};

/**
 * 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.
 * @num_altsetting: number of altsettings defined.
 * @cur_altsetting: the current altsetting.
 * @driver: the USB driver that is bound to this interface.
 * @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())
 * @dev: driver model's view of this device
 * @class_dev: driver model's class view of this device.
 *
 * 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 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 */

	int minor;			/* minor number this interface is bound to */
	enum usb_interface_condition condition;		/* state of binding */
	struct device dev;		/* interface specific device info */
	struct class_device *class_dev;
};
#define	to_usb_interface(d) container_of(d, struct usb_interface, dev)
#define	interface_to_usbdev(intf) \
	container_of(intf->dev.parent, struct usb_device, dev)

static inline void *usb_get_intfdata (struct usb_interface *intf)
{
	return dev_get_drvdata (&intf->dev);
}

static inline void usb_set_intfdata (struct usb_interface *intf, void *data)
{
	dev_set_drvdata(&intf->dev, data);
}

struct usb_interface *usb_get_intf(struct usb_interface *intf);
void usb_put_intf(struct usb_interface *intf);

/* this maximum is arbitrary */
#define USB_MAXINTERFACES	32

/**
 * struct usb_interface_cache - long-term representation of a device interface
 * @num_altsetting: number of altsettings defined.
 * @ref: reference counter.
 * @altsetting: variable-length 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.
 *
 * These structures persist for the lifetime of a usb_device, unlike
 * struct usb_interface (which persists only as long as its configuration
 * is installed).  The altsetting arrays can be accessed through these
 * structures at any time, permitting comparison of configurations and
 * providing support for the /proc/bus/usb/devices pseudo-file.
 */
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];
};
#define	ref_to_usb_interface_cache(r) \
		container_of(r, struct usb_interface_cache, ref)
#define	altsetting_to_usb_interface_cache(a) \
		container_of(a, struct usb_interface_cache, altsetting[0])

/**
 * 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.
 * @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 hotplug scripts).  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;
	/* 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;
};

int __usb_get_extra_descriptor(char *buffer, unsigned size,
	unsigned char type, void **ptr);
#define usb_get_extra_descriptor(ifpoint,type,ptr)\
	__usb_get_extra_descriptor((ifpoint)->extra,(ifpoint)->extralen,\
		type,(void**)ptr)

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

struct usb_operations;

/* USB device number allocation bitmap */
struct usb_devmap {
	unsigned long devicemap[128 / (8*sizeof(unsigned long))];
};

/*
 * Allocated per bus (tree of devices) we have:
 */
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 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_operations *op;	/* Operations (specific to the HC) */
	struct usb_device *root_hub;	/* Root hub */
	struct list_head bus_list;	/* list of busses */
	void *hcpriv;                   /* Host Controller private data */

	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 */

	struct dentry *usbfs_dentry;	/* usbfs dentry entry for the bus */