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path: root/drivers/usb/core/hcd.h
blob: ec5c67ea07b745a95b92e8db88349abadc1bbca1 (plain)
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/*
 * Copyright (c) 2001-2002 by David Brownell
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef __USB_CORE_HCD_H
#define __USB_CORE_HCD_H

#ifdef __KERNEL__

#include <linux/rwsem.h>

#define MAX_TOPO_LEVEL		6

/* This file contains declarations of usbcore internals that are mostly
 * used or exposed by Host Controller Drivers.
 */

/*
 * USB Packet IDs (PIDs)
 */
#define USB_PID_EXT			0xf0	/* USB 2.0 LPM ECN */
#define USB_PID_OUT			0xe1
#define USB_PID_ACK			0xd2
#define USB_PID_DATA0			0xc3
#define USB_PID_PING			0xb4	/* USB 2.0 */
#define USB_PID_SOF			0xa5
#define USB_PID_NYET			0x96	/* USB 2.0 */
#define USB_PID_DATA2			0x87	/* USB 2.0 */
#define USB_PID_SPLIT			0x78	/* USB 2.0 */
#define USB_PID_IN			0x69
#define USB_PID_NAK			0x5a
#define USB_PID_DATA1			0x4b
#define USB_PID_PREAMBLE		0x3c	/* Token mode */
#define USB_PID_ERR			0x3c	/* USB 2.0: handshake mode */
#define USB_PID_SETUP			0x2d
#define USB_PID_STALL			0x1e
#define USB_PID_MDATA			0x0f	/* USB 2.0 */

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

/*
 * USB Host Controller Driver (usb_hcd) framework
 *
 * Since "struct usb_bus" is so thin, you can't share much code in it.
 * This framework is a layer over that, and should be more sharable.
 *
 * @authorized_default: Specifies if new devices are authorized to
 *                      connect by default or they require explicit
 *                      user space authorization; this bit is settable
 *                      through /sys/class/usb_host/X/authorized_default.
 *                      For the rest is RO, so we don't lock to r/w it.
 */

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

struct usb_hcd {

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

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

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

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

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

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

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

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

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

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

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

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

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

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

/* 2.4 does this a bit differently ... */
static inline struct usb_bus *hcd_to_bus(struct usb_hcd *hcd)
{
	return &hcd->self;
}

static inline struct usb_hcd *bus_to_hcd(struct usb_bus *bus)
{
	return container_of(bus, struct usb_hcd, self);
}

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

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


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

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

	int	flags;
#define	HCD_MEMORY	0x0001		/* HC regs use memory (else I/O) */
#define	HCD_LOCAL_MEM	0x0002		/* HC needs local memory */
#define	HCD_USB11	0x0010		/* USB 1.1 */
#define	HCD_USB2	0x0020		/* USB 2.0 */
#define	HCD_USB3	0x0040		/* USB 3.0 */
#define	HCD_MASK	0x0070

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

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

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

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

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

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

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

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

	/* (optional) reset any endpoint state such as sequence number
	   and current window */
	void 	(*endpoint_reset)(struct usb_hcd *hcd,
			struct usb_host_endpoint *ep);

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

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

		/* CLEAR_TT_BUFFER completion callback */
	void	(*clear_tt_buffer_complete)(struct usb_hcd *,
				struct usb_host_endpoint *);

	/* xHCI specific functions */
		/* Called by usb_alloc_dev to alloc HC device structures */
	int	(*alloc_dev)(struct usb_hcd *, struct usb_device *);
		/* Called by usb_release_dev to free HC device structures */
	void	(*free_dev)(struct usb_hcd *, struct usb_device *);

	/* Bandwidth computation functions */
	/* Note that add_endpoint() can only be called once per endpoint before
	 * check_bandwidth() or reset_bandwidth() must be called.
	 * drop_endpoint() can only be called once per endpoint also.
	 * A call to xhci_drop_endpoint() followed by a call to xhci_add_endpoint() will
	 * add the endpoint to the schedule with possibly new parameters denoted by a
	 * different endpoint descriptor in usb_host_endpoint.
	 * A call to xhci_add_endpoint() followed by a call to xhci_drop_endpoint() is
	 * not allowed.
	 */
		/* Allocate endpoint resources and add them to a new schedule */
	int 	(*add_endpoint)(struct usb_hcd *, struct usb_device *, struct usb_host_endpoint *);
		/* Drop an endpoint from a new schedule */
	int 	(*drop_endpoint)(struct usb_hcd *, struct usb_device *, struct usb_host_endpoint *);
		/* Check that a new hardware configuration, set using
		 * endpoint_enable and endpoint_disable, does not exceed bus
		 * bandwidth.  This must be called before any set configuration
		 * or set interface requests are sent to the device.
		 */
	int	(*check_bandwidth)(struct usb_hcd *, struct usb_device *);
		/* Reset the device schedule to the last known good schedule,
		 * which was set from a previous successful call to
		 * check_bandwidth().  This reverts any add_endpoint() and
		 * drop_endpoint() calls since that last successful call.
		 * Used for when a check_bandwidth() call fails due to resource
		 * or bandwidth constraints.
		 */
	void	(*reset_bandwidth)(struct usb_hcd *, struct usb_device *);
		/* Returns the hardware-chosen device address */
	int	(*address_device)(struct usb_hcd *, struct usb_device *udev);
};

extern int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb);
extern int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
		int status);
extern void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb);

extern int usb_hcd_submit_urb(struct urb *urb, gfp_t mem_flags);
extern int usb_hcd_unlink_urb(struct urb *urb, int status);
extern void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb,
		int status);
extern void usb_hcd_flush_endpoint(struct usb_device *udev,
		struct usb_host_endpoint *ep);
extern void usb_hcd_disable_endpoint(struct usb_device *udev,
		struct usb_host_endpoint *ep);
extern void usb_hcd_reset_endpoint(struct usb_device *udev,
		struct usb_host_endpoint *ep);
extern void usb_hcd_synchronize_unlinks(struct usb_device *udev);
extern int usb_hcd_check_bandwidth(struct usb_device *udev,
		struct usb_host_config *new_config,
		struct usb_interface *new_intf);
extern int usb_hcd_get_frame_number(struct usb_device *udev);

extern struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
		struct device *dev, const char *bus_name);
extern struct usb_hcd *usb_get_hcd(struct usb_hcd *hcd);
extern void usb_put_hcd(struct usb_hcd *hcd);
extern int usb_add_hcd(struct usb_hcd *hcd,
		unsigned int irqnum, unsigned long irqflags);
extern void usb_remove_hcd(struct usb_hcd *hcd);

struct platform_device;
extern void usb_hcd_platform_shutdown(struct platform_device *dev);

#ifdef CONFIG_PCI
struct pci_dev;
struct pci_device_id;
extern int usb_hcd_pci_probe(struct pci_dev *dev,
				const struct pci_device_id *id);
extern void usb_hcd_pci_remove(struct pci_dev *dev);
extern void usb_hcd_pci_shutdown(struct pci_dev *dev);

#ifdef CONFIG_PM_SLEEP
extern struct dev_pm_ops	usb_hcd_pci_pm_ops;
#endif
#endif /* CONFIG_PCI */

/* pci-ish (pdev null is ok) buffer alloc/mapping support */
int hcd_buffer_create(struct usb_hcd *hcd);
void hcd_buffer_destroy(struct usb_hcd *hcd);

void *hcd_buffer_alloc(struct usb_bus *bus, size_t size,
	gfp_t mem_flags, dma_addr_t *dma);
void hcd_buffer_free(struct usb_bus *bus, size_t size,
	void *addr, dma_addr_t dma);

/* generic bus glue, needed for host controllers that don't use PCI */
extern irqreturn_t usb_hcd_irq(int irq, void *__hcd);

extern void usb_hc_died(struct usb_hcd *hcd);
extern void usb_hcd_poll_rh_status(struct usb_hcd *hcd);

/* The D0/D1 toggle bits ... USE WITH CAUTION (they're almost hcd-internal) */
#define usb_gettoggle(dev, ep, out) (((dev)->toggle[out] >> (ep)) & 1)
#define	usb_dotoggle(dev, ep, out)  ((dev)->toggle[out] ^= (1 << (ep)))
#define usb_settoggle(dev, ep, out, bit) \
		((dev)->toggle[out] = ((dev)->toggle[out] & ~(1 << (ep))) | \
		 ((bit) << (ep)))

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

/* Enumeration is only for the hub driver, or HCD virtual root hubs */
extern struct usb_device *usb_alloc_dev(struct usb_device *parent,
					struct usb_bus *, unsigned port);
extern int usb_new_device(struct usb_device *dev);
extern void usb_disconnect(struct usb_device **);

extern int usb_get_configuration(struct usb_device *dev);
extern void usb_destroy_configuration(struct usb_device *dev);

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

/*
 * HCD Root Hub support
 */

#include "hub.h"

/* (shifted) direction/type/recipient from the USB 2.0 spec, table 9.2 */
#define DeviceRequest \
	((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE)<<8)
#define DeviceOutRequest \
	((USB_DIR_OUT|USB_TYPE_STANDARD|USB_RECIP_DEVICE)<<8)

#define InterfaceRequest \
	((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_INTERFACE)<<8)

#define EndpointRequest \
	((USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_INTERFACE)<<8)
#define EndpointOutRequest \
	((USB_DIR_OUT|USB_TYPE_STANDARD|USB_RECIP_INTERFACE)<<8)

/* class requests from the USB 2.0 hub spec, table 11-15 */
/* GetBusState and SetHubDescriptor are optional, omitted */
#define ClearHubFeature		(0x2000 | USB_REQ_CLEAR_FEATURE)
#define ClearPortFeature	(0x2300 | USB_REQ_CLEAR_FEATURE)
#define GetHubDescriptor	(0xa000 | USB_REQ_GET_DESCRIPTOR)
#define GetHubStatus		(0xa000 | USB_REQ_GET_STATUS)
#define GetPortStatus		(0xa300 | USB_REQ_GET_STATUS)
#define SetHubFeature		(0x2000 | USB_REQ_SET_FEATURE)
#define SetPortFeature		(0x2300 | USB_REQ_SET_FEATURE)


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

/*
 * Generic bandwidth allocation constants/support
 */
#define FRAME_TIME_USECS	1000L
#define BitTime(bytecount) (7 * 8 * bytecount / 6) /* with integer truncation */
		/* Trying not to use worst-case bit-stuffing
		 * of (7/6 * 8 * bytecount) = 9.33 * bytecount */
		/* bytecount = data payload byte count */

#define NS_TO_US(ns)	((ns + 500L) / 1000L)
			/* convert & round nanoseconds to microseconds */


/*
 * Full/low speed bandwidth allocation constants/support.
 */
#define BW_HOST_DELAY	1000L		/* nanoseconds */
#define BW_HUB_LS_SETUP	333L		/* nanoseconds */
			/* 4 full-speed bit times (est.) */

#define FRAME_TIME_BITS			12000L	/* frame = 1 millisecond */
#define FRAME_TIME_MAX_BITS_ALLOC	(90L * FRAME_TIME_BITS / 100L)
#define FRAME_TIME_MAX_USECS_ALLOC	(90L * FRAME_TIME_USECS / 100L)

/*
 * Ceiling [nano/micro]seconds (typical) for that many bytes at high speed
 * ISO is a bit less, no ACK ... from USB 2.0 spec, 5.11.3 (and needed
 * to preallocate bandwidth)
 */
#define USB2_HOST_DELAY	5	/* nsec, guess */
#define HS_NSECS(bytes) (((55 * 8 * 2083) \
	+ (2083UL * (3 + BitTime(bytes))))/1000 \
	+ USB2_HOST_DELAY)
#define HS_NSECS_ISO(bytes) (((38 * 8 * 2083) \
	+ (2083UL * (3 + BitTime(bytes))))/1000 \
	+ USB2_HOST_DELAY)
#define HS_USECS(bytes) NS_TO_US (HS_NSECS(bytes))
#define HS_USECS_ISO(bytes) NS_TO_US (HS_NSECS_ISO(bytes))

extern long usb_calc_bus_time(int speed, int is_input,
			int isoc, int bytecount);

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

extern void usb_set_device_state(struct usb_device *udev,
		enum usb_device_state new_state);

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

/* exported only within usbcore */

extern struct list_head usb_bus_list;
extern struct mutex usb_bus_list_lock;
extern wait_queue_head_t usb_kill_urb_queue;

extern int usb_find_interface_driver(struct usb_device *dev,
	struct usb_interface *interface);

#define usb_endpoint_out(ep_dir)	(!((ep_dir) & USB_DIR_IN))

#ifdef CONFIG_PM
extern void usb_hcd_resume_root_hub(struct usb_hcd *hcd);
extern void usb_root_hub_lost_power(struct usb_device *rhdev);
extern int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg);
extern int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg);
#else
static inline void usb_hcd_resume_root_hub(struct usb_hcd *hcd)
{
	return;
}
#endif /* CONFIG_PM */

/*
 * USB device fs stuff
 */

#ifdef CONFIG_USB_DEVICEFS

/*
 * these are expected to be called from the USB core/hub thread
 * with the kernel lock held
 */
extern void usbfs_update_special(void);
extern int usbfs_init(void);
extern void usbfs_cleanup(void);

#else /* CONFIG_USB_DEVICEFS */

static inline void usbfs_update_special(void) {}
static inline int usbfs_init(void) { return 0; }
static inline void usbfs_cleanup(void) { }

#endif /* CONFIG_USB_DEVICEFS */

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

#if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)

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

extern struct usb_mon_operations *mon_ops;

static inline void usbmon_urb_submit(struct usb_bus *bus, struct urb *urb)
{
	if (bus->monitored)
		(*mon_ops->urb_submit)(bus, urb);
}

static inline void usbmon_urb_submit_error(struct usb_bus *bus, struct urb *urb,
    int error)
{
	if (bus->monitored)
		(*mon_ops->urb_submit_error)(bus, urb, error);
}

static inline void usbmon_urb_complete(struct usb_bus *bus, struct urb *urb,
		int status)
{
	if (bus->monitored)
		(*mon_ops->urb_complete)(bus, urb, status);
}

int usb_mon_register(struct usb_mon_operations *ops);
void usb_mon_deregister(void);

#else

static inline void usbmon_urb_submit(struct usb_bus *bus, struct urb *urb) {}
static inline void usbmon_urb_submit_error(struct usb_bus *bus, struct urb *urb,
    int error) {}
static inline void usbmon_urb_complete(struct usb_bus *bus, struct urb *urb,
		int status) {}

#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */

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

/* hub.h ... DeviceRemovable in 2.4.2-ac11, gone in 2.4.10 */
/* bleech -- resurfaced in 2.4.11 or 2.4.12 */
#define bitmap 	DeviceRemovable


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

/* random stuff */

#define	RUN_CONTEXT (in_irq() ? "in_irq" \
		: (in_interrupt() ? "in_interrupt" : "can sleep"))


/* This rwsem is for use only by the hub driver and ehci-hcd.
 * Nobody else should touch it.
 */
extern struct rw_semaphore ehci_cf_port_reset_rwsem;

/* Keep track of which host controller drivers are loaded */
#define USB_UHCI_LOADED		0
#define USB_OHCI_LOADED		1
#define USB_EHCI_LOADED		2
extern unsigned long usb_hcds_loaded;

#endif /* __KERNEL__ */

#endif /* __USB_CORE_HCD_H */