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Release 4.12 include/linux/usb.h

Directory: include/linux
#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/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 */
#include <linux/mutex.h>	/* for struct mutex */
#include <linux/pm_runtime.h>	/* for runtime PM */

struct usb_device;
struct usb_driver;
struct wusb_dev;

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

/*
 * 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.
 *  - a SuperSpeed endpoint has a companion descriptor
 *
 * And there might be other descriptors mixed in with those.
 *
 * Devices may also have class-specific or vendor-specific descriptors.
 */

struct ep_device;

/**
 * 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
 * @ssp_isoc_ep_comp: SuperSpeedPlus isoc 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
 * @streams: number of USB-3 streams allocated on the 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 usb_ssp_isoc_ep_comp_descriptor	ssp_isoc_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;
	
int streams;
};

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

	
char *string;		/* iInterface string, if present */
};


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

int __must_check
usb_find_common_endpoints(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in,
		struct usb_endpoint_descriptor **bulk_out,
		struct usb_endpoint_descriptor **int_in,
		struct usb_endpoint_descriptor **int_out);

int __must_check
usb_find_common_endpoints_reverse(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in,
		struct usb_endpoint_descriptor **bulk_out,
		struct usb_endpoint_descriptor **int_in,
		struct usb_endpoint_descriptor **int_out);



static inline int __must_check

usb_find_bulk_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in)
{
	return usb_find_common_endpoints(alt, bulk_in, NULL, NULL, NULL);
}


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static inline int __must_check

usb_find_bulk_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_out)
{
	return usb_find_common_endpoints(alt, NULL, bulk_out, NULL, NULL);
}


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static inline int __must_check

usb_find_int_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_in)
{
	return usb_find_common_endpoints(alt, NULL, NULL, int_in, NULL);
}


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static inline int __must_check

usb_find_int_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_out)
{
	return usb_find_common_endpoints(alt, NULL, NULL, NULL, int_out);
}


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static inline int __must_check

usb_find_last_bulk_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in)
{
	return usb_find_common_endpoints_reverse(alt, bulk_in, NULL, NULL, NULL);
}


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static inline int __must_check

usb_find_last_bulk_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_out)
{
	return usb_find_common_endpoints_reverse(alt, NULL, bulk_out, NULL, NULL);
}


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static inline int __must_check

usb_find_last_int_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_in)
{
	return usb_find_common_endpoints_reverse(alt, NULL, NULL, int_in, NULL);
}


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static inline int __must_check

usb_find_last_int_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_out)
{
	return usb_find_common_endpoints_reverse(alt, NULL, NULL, NULL, int_out);
}


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/**
 * 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.
 * @authorized: This allows to (de)authorize individual interfaces instead
 *      a whole device in contrast to the device authorization.
 * @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.
 * @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 resetting_device:1;	/* true: bandwidth alloc after reset */
	
unsigned authorized:1;		/* used for interface authorization */

	
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 */
};

#define	to_usb_interface(d) container_of(d, struct usb_interface, dev)




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


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


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

/* Hard limit */

#define USB_MAXENDPOINTS	30
/* this maximum is arbitrary */

#define USB_MAXINTERFACES	32

#define USB_MAXIADS		(USB_MAXINTERFACES/2)

/*
 * USB Resume Timer: Every Host controller driver should drive the resume
 * signalling on the bus for the amount of time defined by this macro.
 *
 * That way we will have a 'stable' behavior among all HCDs supported by Linux.
 *
 * Note that the USB Specification states we should drive resume for *at least*
 * 20 ms, but it doesn't give an upper bound. This creates two possible
 * situations which we want to avoid:
 *
 * (a) sometimes an msleep(20) might expire slightly before 20 ms, which causes
 * us to fail USB Electrical Tests, thus failing Certification
 *
 * (b) Some (many) devices actually need more than 20 ms of resume signalling,
 * and while we can argue that's against the USB Specification, we don't have
 * control over which devices a certification laboratory will be using for
 * certification. If CertLab uses a device which was tested against Windows and
 * that happens to have relaxed resume signalling rules, we might fall into
 * situations where we fail interoperability and electrical tests.
 *
 * In order to avoid both conditions, we're using a 40 ms resume timeout, which
 * should cope with both LPJ calibration errors and devices not following every
 * detail of the USB Specification.
 */

#define USB_RESUME_TIMEOUT	40 
/* ms */

/**
 * 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 /sys/kernel/debug/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.
 * @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;
};

/* USB2.0 and USB3.0 device BOS descriptor set */

struct usb_host_bos {
	
struct usb_bos_descriptor	*desc;

	/* wireless cap descriptor is handled by wusb */
	
struct usb_ext_cap_descriptor	*ext_cap;
	
struct usb_ss_cap_descriptor	*ss_cap;
	
struct usb_ssp_cap_descriptor	*ssp_cap;
	
struct usb_ss_container_id_descriptor	*ss_id;
	
struct usb_ptm_cap_descriptor	*ptm_cap;
};

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)

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

/* 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 */
	
struct device *sysdev;		/* as seen from firmware or bus */
	
int busnum;			/* Bus number (in order of reg) */
	
const char *bus_name;		/* stable id (PCI slot_name etc) */
	
u8 uses_dma;			/* Does the host controller use DMA? */
	
u8 uses_pio_for_control;	/*
                                         * Does the host controller use PIO
                                         * for control transfers?
                                         */
	
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? */
	
unsigned no_stop_on_short:1;    /*
                                         * Quirk: some controllers don't stop
                                         * the ep queue on a short transfer
                                         * with the URB_SHORT_NOT_OK flag set.
                                         */
	
unsigned no_sg_constraint:1;	/* no sg constraint */
	
unsigned sg_tablesize;		/* 0 or largest number of sg list entries */

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

	
struct usb_devmap devmap;	/* device address allocation map */
	
struct usb_device *root_hub;	/* Root hub */
	
struct usb_bus *hs_companion;	/* Companion EHCI bus, if any */

	
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 */

	
unsigned resuming_ports;	/* bit array: resuming root-hub ports */

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

struct usb_dev_state;

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

struct usb_tt;


enum usb_device_removable {
	
USB_DEVICE_REMOVABLE_UNKNOWN = 0,
	
USB_DEVICE_REMOVABLE,
	
USB_DEVICE_FIXED,
};


enum usb_port_connect_type {
	
USB_PORT_CONNECT_TYPE_UNKNOWN = 0,
	
USB_PORT_CONNECT_TYPE_HOT_PLUG,
	
USB_PORT_CONNECT_TYPE_HARD_WIRED,
	
USB_PORT_NOT_USED,
};

/*
 * USB 2.0 Link Power Management (LPM) parameters.
 */

struct usb2_lpm_parameters {
	/* Best effort service latency indicate how long the host will drive
         * resume on an exit from L1.
         */
	
unsigned int besl;

	/* Timeout value in microseconds for the L1 inactivity (LPM) timer.
         * When the timer counts to zero, the parent hub will initiate a LPM
         * transition to L1.
         */
	
int timeout;
};

/*
 * USB 3.0 Link Power Management (LPM) parameters.
 *
 * PEL and SEL are USB 3.0 Link PM latencies for device-initiated LPM exit.
 * MEL is the USB 3.0 Link PM latency for host-initiated LPM exit.
 * All three are stored in nanoseconds.
 */

struct usb3_lpm_parameters {
	/*
         * Maximum exit latency (MEL) for the host to send a packet to the
         * device (either a Ping for isoc endpoints, or a data packet for
         * interrupt endpoints), the hubs to decode the packet, and for all hubs
         * in the path to transition the links to U0.
         */
	
unsigned int mel;
	/*
         * Maximum exit latency for a device-initiated LPM transition to bring
         * all links into U0.  Abbreviated as "PEL" in section 9.4.12 of the USB
         * 3.0 spec, with no explanation of what "P" stands for.  "Path"?
         */
	
unsigned int pel;

	/*
         * The System Exit Latency (SEL) includes PEL, and three other
         * latencies.  After a device initiates a U0 transition, it will take
         * some time from when the device sends the ERDY to when it will finally
         * receive the data packet.  Basically, SEL should be the worse-case
         * latency from when a device starts initiating a U0 transition to when
         * it will get data.
         */
	
unsigned int sel;
	/*
         * The idle timeout value that is currently programmed into the parent
         * hub for this device.  When the timer counts to zero, the parent hub
         * will initiate an LPM transition to either U1 or U2.
         */
	
int timeout;
};

/**
 * 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_u1_enabled: USB3 hardware U1 LPM enabled
 * @usb3_lpm_u2_enabled: USB3 hardware U2 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_u1_enabled:1;
	
unsigned usb3_lpm_u2_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;
};

#define	to_usb_device(d) container_of(d, struct usb_device, dev)




static inline struct usb_device *interface_to_usbdev(struct usb_interface *intf)
{
	return to_usb_device(intf->dev.parent);
}


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extern struct usb_device *usb_get_dev(struct usb_device *dev);
extern void usb_put_dev(struct usb_device *dev);
extern struct usb_device *usb_hub_find_child(struct usb_device *hdev,
	int port1);

/**
 * usb_hub_for_each_child - iterate over all child devices on the hub
 * @hdev:  USB device belonging to the usb hub
 * @port1: portnum associated with child device
 * @child: child device pointer
 */

#define usb_hub_for_each_child(hdev, port1, child) \
	for (port1 = 1, child = usb_hub_find_child(hdev, port1); \
                        port1 <= hdev->maxchild; \
                        child = usb_hub_find_child(hdev, ++port1)) \
                if (!child) continue; else

/* USB device locking */

#define usb_lock_device(udev)			device_lock(&(udev)->dev)

#define usb_unlock_device(udev)			device_unlock(&(udev)->dev)

#define usb_lock_device_interruptible(udev)	device_lock_interruptible(&(udev)->dev)

#define usb_trylock_device(udev)		device_trylock(&(udev)->dev)
extern int usb_lock_device_for_reset(struct usb_device *udev,
				     const struct usb_interface *iface);

/* USB port reset for device reinitialization */
extern int usb_reset_device(struct usb_device *dev);
extern void usb_queue_reset_device(struct usb_interface *dev);

#ifdef CONFIG_ACPI
extern int usb_acpi_set_power_state(struct usb_device *hdev, int index,
	bool enable);
extern bool usb_acpi_power_manageable(struct usb_device *hdev, int index);
#else



static inline int usb_acpi_set_power_state(struct usb_device *hdev, int index,
	bool enable) { return 0; }

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static inline bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
	{ return true; }

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#endif

/* USB autosuspend and autoresume */
#ifdef CONFIG_PM
extern void usb_enable_autosuspend(struct usb_device *udev);
extern void usb_disable_autosuspend(struct usb_device *udev);

extern int usb_autopm_get_interface(struct usb_interface *intf);
extern void usb_autopm_put_interface(struct usb_interface *intf);
extern int usb_autopm_get_interface_async(struct usb_interface *intf);
extern void usb_autopm_put_interface_async(struct usb_interface *intf);
extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);




static inline void usb_mark_last_busy(struct usb_device *udev)
{
	pm_runtime_mark_last_busy(&udev->dev);
}


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#else




static inline int usb_enable_autosuspend(struct usb_device *udev)
{ return 0; }

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static inline int usb_disable_autosuspend(struct usb_device *udev)
{ return 0; }


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static inline int usb_autopm_get_interface(struct usb_interface *intf)
{ return 0; }

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static inline int usb_autopm_get_interface_async(struct usb_interface *intf)
{ return 0; }


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static inline void usb_autopm_put_interface(struct usb_interface *intf)
{ }

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static inline void usb_autopm_put_interface_async(struct usb_interface *intf)
{ }

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static inline void usb_autopm_get_interface_no_resume(
		struct usb_interface *intf)
{ }

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static inline void usb_autopm_put_interface_no_suspend(
		struct usb_interface *intf)
{ }

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static inline void usb_mark_last_busy(struct usb_device *udev)
{ }

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#endif

extern int usb_disable_lpm(struct usb_device *udev);
extern void usb_enable_lpm(struct usb_device *udev);
/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
extern int usb_unlocked_disable_lpm(struct usb_device *udev);
extern void usb_unlocked_enable_lpm(struct usb_device *udev);

extern int usb_disable_ltm(struct usb_device *udev);
extern void usb_enable_ltm(struct usb_device *udev);




static inline bool usb_device_supports_ltm(struct usb_device *udev)
{
	if (udev->speed < USB_SPEED_SUPER || !udev->bos || !udev->bos->ss_cap)
		return false;
	return udev->bos->ss_cap->bmAttributes & USB_LTM_SUPPORT;
}


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static inline bool usb_device_no_sg_constraint(struct usb_device *udev)
{
	return udev && udev->bus && udev->bus->no_sg_constraint;
}



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

/* for drivers using iso endpoints */
extern int usb_get_current_frame_number(struct usb_device *usb_dev);

/* Sets up a group of bulk endpoints to support multiple stream IDs. */
extern int usb_alloc_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		unsigned int num_streams, gfp_t mem_flags);

/* Reverts a group of bulk endpoints back to not using stream IDs. */
extern int usb_free_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		gfp_t mem_flags);

/* used these for multi-interface device registration */
extern int usb_driver_claim_interface(struct usb_driver *driver,
			struct usb_interface *iface, void *priv);

/**
 * usb_interface_claimed - returns true iff an interface is claimed
 * @iface: the interface being checked
 *
 * Return: %true (nonzero) iff the interface is claimed, else %false
 * (zero).
 *
 * Note:
 * Callers must own the driver model's usb bus readlock.  So driver
 * probe() entries don't need extra locking, but other call contexts
 * may need to explicitly claim that lock.
 *
 */



static inline int usb_interface_claimed(struct usb_interface *iface)
{
	return (iface->dev.driver != NULL);
}


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extern void usb_driver_release_interface(struct usb_driver *driver,
			struct usb_interface *iface);
const struct usb_device_id *usb_match_id(struct usb_interface *interface,
					 const struct usb_device_id *id);
extern int usb_match_one_id(struct usb_interface *interface,
			    const struct usb_device_id *id);

extern int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *));
extern struct usb_interface *usb_find_interface(struct usb_driver *drv,
		int minor);
extern struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
		unsigned ifnum);
extern struct usb_host_interface *usb_altnum_to_altsetting(
		const struct usb_interface *intf, unsigned int altnum);
extern struct usb_host_interface *usb_find_alt_setting(
		struct usb_host_config *config,
		unsigned int iface_num,
		unsigned int alt_num);

/* port claiming functions */
int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
		struct usb_dev_state *owner);
int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
		struct usb_dev_state *owner);

/**
 * usb_make_path - returns stable device path in the usb tree
 * @dev: the device whose path is being constructed
 * @buf: where to put the string
 * @size: how big is "buf"?
 *
 * Return: Length of the string (> 0) or negative if size was too small.
 *
 * Note:
 * This identifier is intended to be "stable", reflecting physical paths in
 * hardware such as physical bus addresses for host controllers or ports on
 * USB hubs.  That makes it stay the same until systems are physically
 * reconfigured, by re-cabling a tree of USB devices or by moving USB host
 * controllers.  Adding and removing devices, including virtual root hubs
 * in host controller driver modules, does not change these path identifiers;
 * neither does rebooting or re-enumerating.  These are more useful identifiers
 * than changeable ("unstable") ones like bus numbers or device addresses.
 *
 * With a partial exception for devices connected to USB 2.0 root hubs, these
 * identifiers are also predictable.  So long as the device tree isn't changed,
 * plugging any USB device into a given hub port always gives it the same path.
 * Because of the use of "companion" controllers, devices connected to ports on
 * USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are
 * high speed, and a different one if they are full or low speed.
 */



static inline int usb_make_path(struct usb_device *dev, char *buf, size_t size)
{
	int actual;
	actual = snprintf(buf, size, "usb-%s-%s", dev->bus->bus_name,
			  dev->devpath);
	return (actual >= (int)size) ? -1 : actual;
}


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


#define USB_DEVICE_ID_MATCH_DEVICE \
		(USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT)

#define USB_DEVICE_ID_MATCH_DEV_RANGE \
		(USB_DEVICE_ID_MATCH_DEV_LO | USB_DEVICE_ID_MATCH_DEV_HI)

#define USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION \
		(USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_RANGE)

#define USB_DEVICE_ID_MATCH_DEV_INFO \
		(USB_DEVICE_ID_MATCH_DEV_CLASS | \
                USB_DEVICE_ID_MATCH_DEV_SUBCLASS | \
                USB_DEVICE_ID_MATCH_DEV_PROTOCOL)

#define USB_DEVICE_ID_MATCH_INT_INFO \
		(USB_DEVICE_ID_MATCH_INT_CLASS | \
                USB_DEVICE_ID_MATCH_INT_SUBCLASS | \
                USB_DEVICE_ID_MATCH_INT_PROTOCOL)

/**
 * 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)
/**
 * USB_DEVICE_VER - describe a specific usb device with a version range
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @lo: the bcdDevice_lo value
 * @hi: the bcdDevice_hi value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device, with a version range.
 */

#define USB_DEVICE_VER(vend, prod, lo, hi) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION, \
        .idVendor = (vend), \
        .idProduct = (prod), \
        .bcdDevice_lo = (lo), \
        .bcdDevice_hi = (hi)

/**
 * USB_DEVICE_INTERFACE_CLASS - describe a usb device with a specific interface class
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @cl: bInterfaceClass value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface class of devices.
 */

#define USB_DEVICE_INTERFACE_CLASS(vend, prod, cl) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
                       USB_DEVICE_ID_MATCH_INT_CLASS, \
        .idVendor = (vend), \
        .idProduct = (prod), \
        .bInterfaceClass = (cl)

/**
 * USB_DEVICE_INTERFACE_PROTOCOL - describe a usb device with a specific interface protocol
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface protocol of devices.
 */

#define USB_DEVICE_INTERFACE_PROTOCOL(vend, prod, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
                       USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
        .idVendor = (vend), \
        .idProduct = (prod), \
        .bInterfaceProtocol = (pr)

/**
 * USB_DEVICE_INTERFACE_NUMBER - describe a usb device with a specific interface number
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @num: bInterfaceNumber value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface number of devices.
 */

#define USB_DEVICE_INTERFACE_NUMBER(vend, prod, num) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
                       USB_DEVICE_ID_MATCH_INT_NUMBER, \
        .idVendor = (vend), \
        .idProduct = (prod), \
        .bInterfaceNumber = (num)

/**
 * USB_DEVICE_INFO - macro used to describe a class of usb devices
 * @cl: bDeviceClass value
 * @sc: bDeviceSubClass value
 * @pr: bDeviceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific class of devices.
 */

#define USB_DEVICE_INFO(cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_DEV_INFO, \
        .bDeviceClass = (cl), \
        .bDeviceSubClass = (sc), \
        .bDeviceProtocol = (pr)

/**
 * USB_INTERFACE_INFO - macro used to describe a class of usb interfaces
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific class of interfaces.
 */

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

/**
 * USB_DEVICE_AND_INTERFACE_INFO - describe a specific usb device with a class of usb interfaces
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device with a specific class of interfaces.
 *
 * This is especially useful when explicitly matching devices that have
 * vendor specific bDeviceClass values, but standards-compliant interfaces.
 */

#define USB_DEVICE_AND_INTERFACE_INFO(vend, prod, cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
                | USB_DEVICE_ID_MATCH_DEVICE, \
        .idVendor = (vend), \
        .idProduct = (prod), \
        .bInterfaceClass = (cl), \
        .bInterfaceSubClass = (sc), \
        .bInterfaceProtocol = (pr)

/**
 * USB_VENDOR_AND_INTERFACE_INFO - describe a specific usb vendor with a class of usb interfaces
 * @vend: the 16 bit USB Vendor ID
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific vendor with a specific class of interfaces.
 *
 * This is especially useful when explicitly matching devices that have
 * vendor specific bDeviceClass values, but standards-compliant interfaces.
 */

#define USB_VENDOR_AND_INTERFACE_INFO(vend, cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
                | USB_DEVICE_ID_MATCH_VENDOR, \
        .idVendor = (vend), \
        .bInterfaceClass = (cl), \
        .bInterfaceSubClass = (sc), \
        .bInterfaceProtocol = (pr)

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

/* Stuff for dynamic usb ids */

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


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

extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
				const struct usb_device_id *id_table,
				struct device_driver *driver,
				const char *buf, size_t count);

extern ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf);

/**
 * struct usbdrv_wrap - wrapper for driver-model structure
 * @driver: The driver-model core driver structure.
 * @for_devices: Non-zero for device drivers, 0 for interface drivers.
 */

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

/**
 * 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
 *      usb_set_intfdata() 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 -ENODEV, if genuine IO errors occurred, an appropriate
 *      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.
 * @unlocked_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 either from system sleep or runtime suspend context. The
 *      return value will be ignored in system sleep context, so do NOT
 *      try to continue using the device if suspend fails in this case.
 *      Instead, let the resume or reset-resume routine recover from
 *      the failure.
 * @resume: Called when the device is being resumed by the system.
 * @reset_resume: Called when the suspended device has been reset instead
 *      of being resumed.
 * @pre_reset: Called by usb_reset_device() when the device is about to be
 *      reset.  This routine must not return until the driver has no active
 *      URBs for the device, and no more URBs may be submitted until the
 *      post_reset method is called.
 * @post_reset: Called by usb_reset_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.
 * @soft_unbind: if set to 1, the USB core will not kill URBs and disable
 *      endpoints before calling the driver's disconnect method.
 * @disable_hub_initiated_lpm: if set to 1, the USB core will not allow hubs
 *      to initiate lower power link state transitions when an idle timeout
 *      occurs.  Device-initiated USB 3.0 link PM will still be allowed.
 *
 * 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 *