drivers/usb/host/uhci-hcd.h - fp2-dev/kernel/msm - Gitiles

 #ifndef __LINUX_UHCI_HCD_H
 #define __LINUX_UHCI_HCD_H

 #include <linux/list.h>
 #include <linux/usb.h>

 #define usb_packetid(pipe)	(usb_pipein(pipe) ? USB_PID_IN : USB_PID_OUT)
 #define PIPE_DEVEP_MASK		0x0007ff00

 /*
  * Universal Host Controller Interface data structures and defines
  */

 /* Command register */
 #define USBCMD		0
 #define   USBCMD_RS		0x0001	/* Run/Stop */
 #define   USBCMD_HCRESET	0x0002	/* Host reset */
 #define   USBCMD_GRESET		0x0004	/* Global reset */
 #define   USBCMD_EGSM		0x0008	/* Global Suspend Mode */
 #define   USBCMD_FGR		0x0010	/* Force Global Resume */
 #define   USBCMD_SWDBG		0x0020	/* SW Debug mode */
 #define   USBCMD_CF		0x0040	/* Config Flag (sw only) */
 #define   USBCMD_MAXP		0x0080	/* Max Packet (0 = 32, 1 = 64) */

 /* Status register */
 #define USBSTS		2
 #define   USBSTS_USBINT		0x0001	/* Interrupt due to IOC */
 #define   USBSTS_ERROR		0x0002	/* Interrupt due to error */
 #define   USBSTS_RD		0x0004	/* Resume Detect */
 #define   USBSTS_HSE		0x0008	/* Host System Error - basically PCI problems */
 #define   USBSTS_HCPE		0x0010	/* Host Controller Process Error - the scripts were buggy */
 #define   USBSTS_HCH		0x0020	/* HC Halted */

 /* Interrupt enable register */
 #define USBINTR		4
 #define   USBINTR_TIMEOUT	0x0001	/* Timeout/CRC error enable */
 #define   USBINTR_RESUME	0x0002	/* Resume interrupt enable */
 #define   USBINTR_IOC		0x0004	/* Interrupt On Complete enable */
 #define   USBINTR_SP		0x0008	/* Short packet interrupt enable */

 #define USBFRNUM	6
 #define USBFLBASEADD	8
 #define USBSOF		12

 /* USB port status and control registers */
 #define USBPORTSC1	16
 #define USBPORTSC2	18
 #define   USBPORTSC_CCS		0x0001	/* Current Connect Status ("device present") */
 #define   USBPORTSC_CSC		0x0002	/* Connect Status Change */
 #define   USBPORTSC_PE		0x0004	/* Port Enable */
 #define   USBPORTSC_PEC		0x0008	/* Port Enable Change */
 #define   USBPORTSC_DPLUS	0x0010	/* D+ high (line status) */
 #define   USBPORTSC_DMINUS	0x0020	/* D- high (line status) */
 #define   USBPORTSC_RD		0x0040	/* Resume Detect */
 #define   USBPORTSC_RES1	0x0080	/* reserved, always 1 */
 #define   USBPORTSC_LSDA	0x0100	/* Low Speed Device Attached */
 #define   USBPORTSC_PR		0x0200	/* Port Reset */
 /* OC and OCC from Intel 430TX and later (not UHCI 1.1d spec) */
 #define   USBPORTSC_OC		0x0400	/* Over Current condition */
 #define   USBPORTSC_OCC		0x0800	/* Over Current Change R/WC */
 #define   USBPORTSC_SUSP	0x1000	/* Suspend */
 #define   USBPORTSC_RES2	0x2000	/* reserved, write zeroes */
 #define   USBPORTSC_RES3	0x4000	/* reserved, write zeroes */
 #define   USBPORTSC_RES4	0x8000	/* reserved, write zeroes */

 /* Legacy support register */
 #define USBLEGSUP		0xc0
 #define   USBLEGSUP_DEFAULT	0x2000	/* only PIRQ enable set */

 #define UHCI_NULL_DATA_SIZE	0x7FF	/* for UHCI controller TD */

 #define UHCI_PTR_BITS		cpu_to_le32(0x000F)
 #define UHCI_PTR_TERM		cpu_to_le32(0x0001)
 #define UHCI_PTR_QH		cpu_to_le32(0x0002)
 #define UHCI_PTR_DEPTH		cpu_to_le32(0x0004)
 #define UHCI_PTR_BREADTH	cpu_to_le32(0x0000)

 #define UHCI_NUMFRAMES		1024	/* in the frame list [array] */
 #define UHCI_MAX_SOF_NUMBER	2047	/* in an SOF packet */
 #define CAN_SCHEDULE_FRAMES	1000	/* how far future frames can be scheduled */

 struct uhci_frame_list {
 	__le32 frame[UHCI_NUMFRAMES];

 	void *frame_cpu[UHCI_NUMFRAMES];

 	dma_addr_t dma_handle;
 };

 struct urb_priv;

 /*
  * One role of a QH is to hold a queue of TDs for some endpoint.  Each QH is
  * used with one URB, and qh->element (updated by the HC) is either:
  *   - the next unprocessed TD for the URB, or
  *   - UHCI_PTR_TERM (when there's no more traffic for this endpoint), or
  *   - the QH for the next URB queued to the same endpoint.
  *
  * The other role of a QH is to serve as a "skeleton" framelist entry, so we
  * can easily splice a QH for some endpoint into the schedule at the right
  * place.  Then qh->element is UHCI_PTR_TERM.
  *
  * In the frame list, qh->link maintains a list of QHs seen by the HC:
  *     skel1 --> ep1-qh --> ep2-qh --> ... --> skel2 --> ...
  */
 struct uhci_qh {
 	/* Hardware fields */
 	__le32 link;			/* Next queue */
 	__le32 element;			/* Queue element pointer */

 	/* Software fields */
 	dma_addr_t dma_handle;

 	struct usb_device *dev;
 	struct urb_priv *urbp;

 	struct list_head list;		/* P: uhci->frame_list_lock */
 	struct list_head remove_list;	/* P: uhci->remove_list_lock */
 } __attribute__((aligned(16)));

 /*
  * We need a special accessor for the element pointer because it is
  * subject to asynchronous updates by the controller
  */
 static __le32 inline qh_element(struct uhci_qh *qh) {
 	__le32 element = qh->element;

 	barrier();
 	return element;
 }

 /*
  * for TD <status>:
  */
 #define TD_CTRL_SPD		(1 << 29)	/* Short Packet Detect */
 #define TD_CTRL_C_ERR_MASK	(3 << 27)	/* Error Counter bits */
 #define TD_CTRL_C_ERR_SHIFT	27
 #define TD_CTRL_LS		(1 << 26)	/* Low Speed Device */
 #define TD_CTRL_IOS		(1 << 25)	/* Isochronous Select */
 #define TD_CTRL_IOC		(1 << 24)	/* Interrupt on Complete */
 #define TD_CTRL_ACTIVE		(1 << 23)	/* TD Active */
 #define TD_CTRL_STALLED		(1 << 22)	/* TD Stalled */
 #define TD_CTRL_DBUFERR		(1 << 21)	/* Data Buffer Error */
 #define TD_CTRL_BABBLE		(1 << 20)	/* Babble Detected */
 #define TD_CTRL_NAK		(1 << 19)	/* NAK Received */
 #define TD_CTRL_CRCTIMEO	(1 << 18)	/* CRC/Time Out Error */
 #define TD_CTRL_BITSTUFF	(1 << 17)	/* Bit Stuff Error */
 #define TD_CTRL_ACTLEN_MASK	0x7FF	/* actual length, encoded as n - 1 */

 #define TD_CTRL_ANY_ERROR	(TD_CTRL_STALLED | TD_CTRL_DBUFERR | \
 				 TD_CTRL_BABBLE | TD_CTRL_CRCTIME | TD_CTRL_BITSTUFF)

 #define uhci_maxerr(err)		((err) << TD_CTRL_C_ERR_SHIFT)
 #define uhci_status_bits(ctrl_sts)	((ctrl_sts) & 0xF60000)
 #define uhci_actual_length(ctrl_sts)	(((ctrl_sts) + 1) & TD_CTRL_ACTLEN_MASK) /* 1-based */

 /*
  * for TD <info>: (a.k.a. Token)
  */
 #define td_token(td)		le32_to_cpu((td)->token)
 #define TD_TOKEN_DEVADDR_SHIFT	8
 #define TD_TOKEN_TOGGLE_SHIFT	19
 #define TD_TOKEN_TOGGLE		(1 << 19)
 #define TD_TOKEN_EXPLEN_SHIFT	21
 #define TD_TOKEN_EXPLEN_MASK	0x7FF		/* expected length, encoded as n - 1 */
 #define TD_TOKEN_PID_MASK	0xFF

 #define uhci_explen(len)	((len) << TD_TOKEN_EXPLEN_SHIFT)

 #define uhci_expected_length(token) ((((token) >> 21) + 1) & TD_TOKEN_EXPLEN_MASK)
 #define uhci_toggle(token)	(((token) >> TD_TOKEN_TOGGLE_SHIFT) & 1)
 #define uhci_endpoint(token)	(((token) >> 15) & 0xf)
 #define uhci_devaddr(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7f)
 #define uhci_devep(token)	(((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7ff)
 #define uhci_packetid(token)	((token) & TD_TOKEN_PID_MASK)
 #define uhci_packetout(token)	(uhci_packetid(token) != USB_PID_IN)
 #define uhci_packetin(token)	(uhci_packetid(token) == USB_PID_IN)

 /*
  * The documentation says "4 words for hardware, 4 words for software".
  *
  * That's silly, the hardware doesn't care. The hardware only cares that
  * the hardware words are 16-byte aligned, and we can have any amount of
  * sw space after the TD entry as far as I can tell.
  *
  * But let's just go with the documentation, at least for 32-bit machines.
  * On 64-bit machines we probably want to take advantage of the fact that
  * hw doesn't really care about the size of the sw-only area.
  *
  * Alas, not anymore, we have more than 4 words for software, woops.
  * Everything still works tho, surprise! -jerdfelt
  *
  * td->link points to either another TD (not necessarily for the same urb or
  * even the same endpoint), or nothing (PTR_TERM), or a QH (for queued urbs)
  */
 struct uhci_td {
 	/* Hardware fields */
 	__le32 link;
 	__le32 status;
 	__le32 token;
 	__le32 buffer;

 	/* Software fields */
 	dma_addr_t dma_handle;

 	struct usb_device *dev;
 	struct urb *urb;

 	struct list_head list;		/* P: urb->lock */
 	struct list_head remove_list;	/* P: uhci->td_remove_list_lock */

 	int frame;			/* for iso: what frame? */
 	struct list_head fl_list;	/* P: uhci->frame_list_lock */
 } __attribute__((aligned(16)));

 /*
  * We need a special accessor for the control/status word because it is
  * subject to asynchronous updates by the controller
  */
 static u32 inline td_status(struct uhci_td *td) {
 	__le32 status = td->status;

 	barrier();
 	return le32_to_cpu(status);
 }


 /*
  * The UHCI driver places Interrupt, Control and Bulk into QH's both
  * to group together TD's for one transfer, and also to faciliate queuing
  * of URB's. To make it easy to insert entries into the schedule, we have
  * a skeleton of QH's for each predefined Interrupt latency, low-speed
  * control, full-speed control and terminating QH (see explanation for
  * the terminating QH below).
  *
  * When we want to add a new QH, we add it to the end of the list for the
  * skeleton QH.
  *
  * For instance, the queue can look like this:
  *
  * skel int128 QH
  * dev 1 interrupt QH
  * dev 5 interrupt QH
  * skel int64 QH
  * skel int32 QH
  * ...
  * skel int1 QH
  * skel low-speed control QH
  * dev 5 control QH
  * skel full-speed control QH
  * skel bulk QH
  * dev 1 bulk QH
  * dev 2 bulk QH
  * skel terminating QH
  *
  * The terminating QH is used for 2 reasons:
  * - To place a terminating TD which is used to workaround a PIIX bug
  *   (see Intel errata for explanation)
  * - To loop back to the full-speed control queue for full-speed bandwidth
  *   reclamation
  *
  * Isochronous transfers are stored before the start of the skeleton
  * schedule and don't use QH's. While the UHCI spec doesn't forbid the
  * use of QH's for Isochronous, it doesn't use them either. Since we don't
  * need to use them either, we follow the spec diagrams in hope that it'll
  * be more compatible with future UHCI implementations.
  */

 #define UHCI_NUM_SKELQH		12
 #define skel_int128_qh		skelqh[0]
 #define skel_int64_qh		skelqh[1]
 #define skel_int32_qh		skelqh[2]
 #define skel_int16_qh		skelqh[3]
 #define skel_int8_qh		skelqh[4]
 #define skel_int4_qh		skelqh[5]
 #define skel_int2_qh		skelqh[6]
 #define skel_int1_qh		skelqh[7]
 #define skel_ls_control_qh	skelqh[8]
 #define skel_fs_control_qh	skelqh[9]
 #define skel_bulk_qh		skelqh[10]
 #define skel_term_qh		skelqh[11]

 /*
  * Search tree for determining where <interval> fits in the skelqh[]
  * skeleton.
  *
  * An interrupt request should be placed into the slowest skelqh[]
  * which meets the interval/period/frequency requirement.
  * An interrupt request is allowed to be faster than <interval> but not slower.
  *
  * For a given <interval>, this function returns the appropriate/matching
  * skelqh[] index value.
  */
 static inline int __interval_to_skel(int interval)
 {
 	if (interval < 16) {
 		if (interval < 4) {
 			if (interval < 2)
 				return 7;	/* int1 for 0-1 ms */
 			return 6;		/* int2 for 2-3 ms */
 		}
 		if (interval < 8)
 			return 5;		/* int4 for 4-7 ms */
 		return 4;			/* int8 for 8-15 ms */
 	}
 	if (interval < 64) {
 		if (interval < 32)
 			return 3;		/* int16 for 16-31 ms */
 		return 2;			/* int32 for 32-63 ms */
 	}
 	if (interval < 128)
 		return 1;			/* int64 for 64-127 ms */
 	return 0;				/* int128 for 128-255 ms (Max.) */
 }

 /*
  * Device states for the host controller.
  *
  * To prevent "bouncing" in the presence of electrical noise,
  * we insist on a 1-second "grace" period, before switching to
  * the RUNNING or SUSPENDED states, during which the state is
  * not allowed to change.
  *
  * The resume process is divided into substates in order to avoid
  * potentially length delays during the timer handler.
  *
  * States in which the host controller is halted must have values <= 0.
  */
 enum uhci_state {
 	UHCI_RESET,
 	UHCI_RUNNING_GRACE,		/* Before RUNNING */
 	UHCI_RUNNING,			/* The normal state */
 	UHCI_SUSPENDING_GRACE,		/* Before SUSPENDED */
 	UHCI_SUSPENDED = -10,		/* When no devices are attached */
 	UHCI_RESUMING_1,
 	UHCI_RESUMING_2
 };

 /*
  * This describes the full uhci information.
  *
  * Note how the "proper" USB information is just
  * a subset of what the full implementation needs.
  */
 struct uhci_hcd {

 	/* debugfs */
 	struct dentry *dentry;

 	/* Grabbed from PCI */
 	unsigned long io_addr;

 	struct dma_pool *qh_pool;
 	struct dma_pool *td_pool;

 	struct usb_bus *bus;

 	struct uhci_td *term_td;	/* Terminating TD, see UHCI bug */
 	struct uhci_qh *skelqh[UHCI_NUM_SKELQH];	/* Skeleton QH's */

 	spinlock_t lock;
 	struct uhci_frame_list *fl;		/* P: uhci->lock */
 	int fsbr;				/* Full-speed bandwidth reclamation */
 	unsigned long fsbrtimeout;		/* FSBR delay */

 	enum uhci_state state;			/* FIXME: needs a spinlock */
 	unsigned long state_end;		/* Time of next transition */
 	unsigned int frame_number;		/* As of last check */
 	unsigned int is_stopped;
 #define UHCI_IS_STOPPED		9999		/* Larger than a frame # */

 	unsigned int scan_in_progress:1;	/* Schedule scan is running */
 	unsigned int need_rescan:1;		/* Redo the schedule scan */
 	unsigned int resume_detect:1;		/* Need a Global Resume */

 	/* Support for port suspend/resume/reset */
 	unsigned long port_c_suspend;		/* Bit-arrays of ports */
 	unsigned long suspended_ports;
 	unsigned long resuming_ports;
 	unsigned long ports_timeout;		/* Time to stop signalling */

 	/* Main list of URB's currently controlled by this HC */
 	struct list_head urb_list;		/* P: uhci->lock */

 	/* List of QH's that are done, but waiting to be unlinked (race) */
 	struct list_head qh_remove_list;	/* P: uhci->lock */
 	unsigned int qh_remove_age;		/* Age in frames */

 	/* List of TD's that are done, but waiting to be freed (race) */
 	struct list_head td_remove_list;	/* P: uhci->lock */
 	unsigned int td_remove_age;		/* Age in frames */

 	/* List of asynchronously unlinked URB's */
 	struct list_head urb_remove_list;	/* P: uhci->lock */
 	unsigned int urb_remove_age;		/* Age in frames */

 	/* List of URB's awaiting completion callback */
 	struct list_head complete_list;		/* P: uhci->lock */

 	int rh_numports;

 	struct timer_list stall_timer;

 	wait_queue_head_t waitqh;		/* endpoint_disable waiters */
 };

 /* Convert between a usb_hcd pointer and the corresponding uhci_hcd */
 static inline struct uhci_hcd *hcd_to_uhci(struct usb_hcd *hcd)
 {
 	return (struct uhci_hcd *) (hcd->hcd_priv);
 }
 static inline struct usb_hcd *uhci_to_hcd(struct uhci_hcd *uhci)
 {
 	return container_of((void *) uhci, struct usb_hcd, hcd_priv);
 }

 #define uhci_dev(u)	(uhci_to_hcd(u)->self.controller)

 struct urb_priv {
 	struct list_head urb_list;

 	struct urb *urb;

 	struct uhci_qh *qh;		/* QH for this URB */
 	struct list_head td_list;	/* P: urb->lock */

 	unsigned fsbr : 1;		/* URB turned on FSBR */
 	unsigned fsbr_timeout : 1;	/* URB timed out on FSBR */
 	unsigned queued : 1;		/* QH was queued (not linked in) */
 	unsigned short_control_packet : 1;	/* If we get a short packet during */
 						/*  a control transfer, retrigger */
 						/*  the status phase */

 	unsigned long inserttime;	/* In jiffies */
 	unsigned long fsbrtime;		/* In jiffies */

 	struct list_head queue_list;	/* P: uhci->frame_list_lock */
 };

 /*
  * Locking in uhci.c
  *
  * Almost everything relating to the hardware schedule and processing
  * of URBs is protected by uhci->lock.  urb->status is protected by
  * urb->lock; that's the one exception.
  *
  * To prevent deadlocks, never lock uhci->lock while holding urb->lock.
  * The safe order of locking is:
  *
  * #1 uhci->lock
  * #2 urb->lock
  */

 #endif
	#ifndef __LINUX_UHCI_HCD_H
	#define __LINUX_UHCI_HCD_H

	#include <linux/list.h>
	#include <linux/usb.h>

	#define usb_packetid(pipe) (usb_pipein(pipe) ? USB_PID_IN : USB_PID_OUT)
	#define PIPE_DEVEP_MASK 0x0007ff00

	/*
	* Universal Host Controller Interface data structures and defines
	*/

	/* Command register */
	#define USBCMD 0
	#define USBCMD_RS 0x0001 /* Run/Stop */
	#define USBCMD_HCRESET 0x0002 /* Host reset */
	#define USBCMD_GRESET 0x0004 /* Global reset */
	#define USBCMD_EGSM 0x0008 /* Global Suspend Mode */
	#define USBCMD_FGR 0x0010 /* Force Global Resume */
	#define USBCMD_SWDBG 0x0020 /* SW Debug mode */
	#define USBCMD_CF 0x0040 /* Config Flag (sw only) */
	#define USBCMD_MAXP 0x0080 /* Max Packet (0 = 32, 1 = 64) */

	/* Status register */
	#define USBSTS 2
	#define USBSTS_USBINT 0x0001 /* Interrupt due to IOC */
	#define USBSTS_ERROR 0x0002 /* Interrupt due to error */
	#define USBSTS_RD 0x0004 /* Resume Detect */
	#define USBSTS_HSE 0x0008 /* Host System Error - basically PCI problems */
	#define USBSTS_HCPE 0x0010 /* Host Controller Process Error - the scripts were buggy */
	#define USBSTS_HCH 0x0020 /* HC Halted */

	/* Interrupt enable register */
	#define USBINTR 4
	#define USBINTR_TIMEOUT 0x0001 /* Timeout/CRC error enable */
	#define USBINTR_RESUME 0x0002 /* Resume interrupt enable */
	#define USBINTR_IOC 0x0004 /* Interrupt On Complete enable */
	#define USBINTR_SP 0x0008 /* Short packet interrupt enable */

	#define USBFRNUM 6
	#define USBFLBASEADD 8
	#define USBSOF 12

	/* USB port status and control registers */
	#define USBPORTSC1 16
	#define USBPORTSC2 18
	#define USBPORTSC_CCS 0x0001 /* Current Connect Status ("device present") */
	#define USBPORTSC_CSC 0x0002 /* Connect Status Change */
	#define USBPORTSC_PE 0x0004 /* Port Enable */
	#define USBPORTSC_PEC 0x0008 /* Port Enable Change */
	#define USBPORTSC_DPLUS 0x0010 /* D+ high (line status) */
	#define USBPORTSC_DMINUS 0x0020 /* D- high (line status) */
	#define USBPORTSC_RD 0x0040 /* Resume Detect */
	#define USBPORTSC_RES1 0x0080 /* reserved, always 1 */
	#define USBPORTSC_LSDA 0x0100 /* Low Speed Device Attached */
	#define USBPORTSC_PR 0x0200 /* Port Reset */
	/* OC and OCC from Intel 430TX and later (not UHCI 1.1d spec) */
	#define USBPORTSC_OC 0x0400 /* Over Current condition */
	#define USBPORTSC_OCC 0x0800 /* Over Current Change R/WC */
	#define USBPORTSC_SUSP 0x1000 /* Suspend */
	#define USBPORTSC_RES2 0x2000 /* reserved, write zeroes */
	#define USBPORTSC_RES3 0x4000 /* reserved, write zeroes */
	#define USBPORTSC_RES4 0x8000 /* reserved, write zeroes */

	/* Legacy support register */
	#define USBLEGSUP 0xc0
	#define USBLEGSUP_DEFAULT 0x2000 /* only PIRQ enable set */

	#define UHCI_NULL_DATA_SIZE 0x7FF /* for UHCI controller TD */

	#define UHCI_PTR_BITS cpu_to_le32(0x000F)
	#define UHCI_PTR_TERM cpu_to_le32(0x0001)
	#define UHCI_PTR_QH cpu_to_le32(0x0002)
	#define UHCI_PTR_DEPTH cpu_to_le32(0x0004)
	#define UHCI_PTR_BREADTH cpu_to_le32(0x0000)

	#define UHCI_NUMFRAMES 1024 /* in the frame list [array] */
	#define UHCI_MAX_SOF_NUMBER 2047 /* in an SOF packet */
	#define CAN_SCHEDULE_FRAMES 1000 /* how far future frames can be scheduled */

	struct uhci_frame_list {
	__le32 frame[UHCI_NUMFRAMES];

	void *frame_cpu[UHCI_NUMFRAMES];

	dma_addr_t dma_handle;
	};

	struct urb_priv;

	/*
	* One role of a QH is to hold a queue of TDs for some endpoint. Each QH is
	* used with one URB, and qh->element (updated by the HC) is either:
	* - the next unprocessed TD for the URB, or
	* - UHCI_PTR_TERM (when there's no more traffic for this endpoint), or
	* - the QH for the next URB queued to the same endpoint.
	*
	* The other role of a QH is to serve as a "skeleton" framelist entry, so we
	* can easily splice a QH for some endpoint into the schedule at the right
	* place. Then qh->element is UHCI_PTR_TERM.
	*
	* In the frame list, qh->link maintains a list of QHs seen by the HC:
	* skel1 --> ep1-qh --> ep2-qh --> ... --> skel2 --> ...
	*/
	struct uhci_qh {
	/* Hardware fields */
	__le32 link; /* Next queue */
	__le32 element; /* Queue element pointer */

	/* Software fields */
	dma_addr_t dma_handle;

	struct usb_device *dev;
	struct urb_priv *urbp;

	struct list_head list; /* P: uhci->frame_list_lock */
	struct list_head remove_list; /* P: uhci->remove_list_lock */
	} __attribute__((aligned(16)));

	/*
	* We need a special accessor for the element pointer because it is
	* subject to asynchronous updates by the controller
	*/
	static __le32 inline qh_element(struct uhci_qh *qh) {
	__le32 element = qh->element;

	barrier();
	return element;
	}

	/*
	* for TD <status>:
	*/
	#define TD_CTRL_SPD (1 << 29) /* Short Packet Detect */
	#define TD_CTRL_C_ERR_MASK (3 << 27) /* Error Counter bits */
	#define TD_CTRL_C_ERR_SHIFT 27
	#define TD_CTRL_LS (1 << 26) /* Low Speed Device */
	#define TD_CTRL_IOS (1 << 25) /* Isochronous Select */
	#define TD_CTRL_IOC (1 << 24) /* Interrupt on Complete */
	#define TD_CTRL_ACTIVE (1 << 23) /* TD Active */
	#define TD_CTRL_STALLED (1 << 22) /* TD Stalled */
	#define TD_CTRL_DBUFERR (1 << 21) /* Data Buffer Error */
	#define TD_CTRL_BABBLE (1 << 20) /* Babble Detected */
	#define TD_CTRL_NAK (1 << 19) /* NAK Received */
	#define TD_CTRL_CRCTIMEO (1 << 18) /* CRC/Time Out Error */
	#define TD_CTRL_BITSTUFF (1 << 17) /* Bit Stuff Error */
	#define TD_CTRL_ACTLEN_MASK 0x7FF /* actual length, encoded as n - 1 */

	#define TD_CTRL_ANY_ERROR (TD_CTRL_STALLED \| TD_CTRL_DBUFERR \| \
	TD_CTRL_BABBLE \| TD_CTRL_CRCTIME \| TD_CTRL_BITSTUFF)

	#define uhci_maxerr(err) ((err) << TD_CTRL_C_ERR_SHIFT)
	#define uhci_status_bits(ctrl_sts) ((ctrl_sts) & 0xF60000)
	#define uhci_actual_length(ctrl_sts) (((ctrl_sts) + 1) & TD_CTRL_ACTLEN_MASK) /* 1-based */

	/*
	* for TD <info>: (a.k.a. Token)
	*/
	#define td_token(td) le32_to_cpu((td)->token)
	#define TD_TOKEN_DEVADDR_SHIFT 8
	#define TD_TOKEN_TOGGLE_SHIFT 19
	#define TD_TOKEN_TOGGLE (1 << 19)
	#define TD_TOKEN_EXPLEN_SHIFT 21
	#define TD_TOKEN_EXPLEN_MASK 0x7FF /* expected length, encoded as n - 1 */
	#define TD_TOKEN_PID_MASK 0xFF

	#define uhci_explen(len) ((len) << TD_TOKEN_EXPLEN_SHIFT)

	#define uhci_expected_length(token) ((((token) >> 21) + 1) & TD_TOKEN_EXPLEN_MASK)
	#define uhci_toggle(token) (((token) >> TD_TOKEN_TOGGLE_SHIFT) & 1)
	#define uhci_endpoint(token) (((token) >> 15) & 0xf)
	#define uhci_devaddr(token) (((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7f)
	#define uhci_devep(token) (((token) >> TD_TOKEN_DEVADDR_SHIFT) & 0x7ff)
	#define uhci_packetid(token) ((token) & TD_TOKEN_PID_MASK)
	#define uhci_packetout(token) (uhci_packetid(token) != USB_PID_IN)
	#define uhci_packetin(token) (uhci_packetid(token) == USB_PID_IN)

	/*
	* The documentation says "4 words for hardware, 4 words for software".
	*
	* That's silly, the hardware doesn't care. The hardware only cares that
	* the hardware words are 16-byte aligned, and we can have any amount of
	* sw space after the TD entry as far as I can tell.
	*
	* But let's just go with the documentation, at least for 32-bit machines.
	* On 64-bit machines we probably want to take advantage of the fact that
	* hw doesn't really care about the size of the sw-only area.
	*
	* Alas, not anymore, we have more than 4 words for software, woops.
	* Everything still works tho, surprise! -jerdfelt
	*
	* td->link points to either another TD (not necessarily for the same urb or
	* even the same endpoint), or nothing (PTR_TERM), or a QH (for queued urbs)
	*/
	struct uhci_td {
	/* Hardware fields */
	__le32 link;
	__le32 status;
	__le32 token;
	__le32 buffer;

	/* Software fields */
	dma_addr_t dma_handle;

	struct usb_device *dev;
	struct urb *urb;

	struct list_head list; /* P: urb->lock */
	struct list_head remove_list; /* P: uhci->td_remove_list_lock */

	int frame; /* for iso: what frame? */
	struct list_head fl_list; /* P: uhci->frame_list_lock */
	} __attribute__((aligned(16)));

	/*
	* We need a special accessor for the control/status word because it is
	* subject to asynchronous updates by the controller
	*/
	static u32 inline td_status(struct uhci_td *td) {
	__le32 status = td->status;

	barrier();
	return le32_to_cpu(status);
	}


	/*
	* The UHCI driver places Interrupt, Control and Bulk into QH's both
	* to group together TD's for one transfer, and also to faciliate queuing
	* of URB's. To make it easy to insert entries into the schedule, we have
	* a skeleton of QH's for each predefined Interrupt latency, low-speed
	* control, full-speed control and terminating QH (see explanation for
	* the terminating QH below).
	*
	* When we want to add a new QH, we add it to the end of the list for the
	* skeleton QH.
	*
	* For instance, the queue can look like this:
	*
	* skel int128 QH
	* dev 1 interrupt QH
	* dev 5 interrupt QH
	* skel int64 QH
	* skel int32 QH
	* ...
	* skel int1 QH
	* skel low-speed control QH
	* dev 5 control QH
	* skel full-speed control QH
	* skel bulk QH
	* dev 1 bulk QH
	* dev 2 bulk QH
	* skel terminating QH
	*
	* The terminating QH is used for 2 reasons:
	* - To place a terminating TD which is used to workaround a PIIX bug
	* (see Intel errata for explanation)
	* - To loop back to the full-speed control queue for full-speed bandwidth
	* reclamation
	*
	* Isochronous transfers are stored before the start of the skeleton
	* schedule and don't use QH's. While the UHCI spec doesn't forbid the
	* use of QH's for Isochronous, it doesn't use them either. Since we don't
	* need to use them either, we follow the spec diagrams in hope that it'll
	* be more compatible with future UHCI implementations.
	*/

	#define UHCI_NUM_SKELQH 12
	#define skel_int128_qh skelqh[0]
	#define skel_int64_qh skelqh[1]
	#define skel_int32_qh skelqh[2]
	#define skel_int16_qh skelqh[3]
	#define skel_int8_qh skelqh[4]
	#define skel_int4_qh skelqh[5]
	#define skel_int2_qh skelqh[6]
	#define skel_int1_qh skelqh[7]
	#define skel_ls_control_qh skelqh[8]
	#define skel_fs_control_qh skelqh[9]
	#define skel_bulk_qh skelqh[10]
	#define skel_term_qh skelqh[11]

	/*
	* Search tree for determining where <interval> fits in the skelqh[]
	* skeleton.
	*
	* An interrupt request should be placed into the slowest skelqh[]
	* which meets the interval/period/frequency requirement.
	* An interrupt request is allowed to be faster than <interval> but not slower.
	*
	* For a given <interval>, this function returns the appropriate/matching
	* skelqh[] index value.
	*/
	static inline int __interval_to_skel(int interval)
	{
	if (interval < 16) {
	if (interval < 4) {
	if (interval < 2)
	return 7; /* int1 for 0-1 ms */
	return 6; /* int2 for 2-3 ms */
	}
	if (interval < 8)
	return 5; /* int4 for 4-7 ms */
	return 4; /* int8 for 8-15 ms */
	}
	if (interval < 64) {
	if (interval < 32)
	return 3; /* int16 for 16-31 ms */
	return 2; /* int32 for 32-63 ms */
	}
	if (interval < 128)
	return 1; /* int64 for 64-127 ms */
	return 0; /* int128 for 128-255 ms (Max.) */
	}

	/*
	* Device states for the host controller.
	*
	* To prevent "bouncing" in the presence of electrical noise,
	* we insist on a 1-second "grace" period, before switching to
	* the RUNNING or SUSPENDED states, during which the state is
	* not allowed to change.
	*
	* The resume process is divided into substates in order to avoid
	* potentially length delays during the timer handler.
	*
	* States in which the host controller is halted must have values <= 0.
	*/
	enum uhci_state {
	UHCI_RESET,
	UHCI_RUNNING_GRACE, /* Before RUNNING */
	UHCI_RUNNING, /* The normal state */
	UHCI_SUSPENDING_GRACE, /* Before SUSPENDED */
	UHCI_SUSPENDED = -10, /* When no devices are attached */
	UHCI_RESUMING_1,
	UHCI_RESUMING_2
	};

	/*
	* This describes the full uhci information.
	*
	* Note how the "proper" USB information is just
	* a subset of what the full implementation needs.
	*/
	struct uhci_hcd {

	/* debugfs */
	struct dentry *dentry;

	/* Grabbed from PCI */
	unsigned long io_addr;

	struct dma_pool *qh_pool;
	struct dma_pool *td_pool;

	struct usb_bus *bus;

	struct uhci_td term_td; / Terminating TD, see UHCI bug */
	struct uhci_qh skelqh[UHCI_NUM_SKELQH]; / Skeleton QH's */

	spinlock_t lock;
	struct uhci_frame_list fl; / P: uhci->lock */
	int fsbr; /* Full-speed bandwidth reclamation */
	unsigned long fsbrtimeout; /* FSBR delay */

	enum uhci_state state; /* FIXME: needs a spinlock */
	unsigned long state_end; /* Time of next transition */
	unsigned int frame_number; /* As of last check */
	unsigned int is_stopped;
	#define UHCI_IS_STOPPED 9999 /* Larger than a frame # */

	unsigned int scan_in_progress:1; /* Schedule scan is running */
	unsigned int need_rescan:1; /* Redo the schedule scan */
	unsigned int resume_detect:1; /* Need a Global Resume */

	/* Support for port suspend/resume/reset */
	unsigned long port_c_suspend; /* Bit-arrays of ports */
	unsigned long suspended_ports;
	unsigned long resuming_ports;
	unsigned long ports_timeout; /* Time to stop signalling */

	/* Main list of URB's currently controlled by this HC */
	struct list_head urb_list; /* P: uhci->lock */

	/* List of QH's that are done, but waiting to be unlinked (race) */
	struct list_head qh_remove_list; /* P: uhci->lock */
	unsigned int qh_remove_age; /* Age in frames */

	/* List of TD's that are done, but waiting to be freed (race) */
	struct list_head td_remove_list; /* P: uhci->lock */
	unsigned int td_remove_age; /* Age in frames */

	/* List of asynchronously unlinked URB's */
	struct list_head urb_remove_list; /* P: uhci->lock */
	unsigned int urb_remove_age; /* Age in frames */

	/* List of URB's awaiting completion callback */
	struct list_head complete_list; /* P: uhci->lock */

	int rh_numports;

	struct timer_list stall_timer;

	wait_queue_head_t waitqh; /* endpoint_disable waiters */
	};

	/* Convert between a usb_hcd pointer and the corresponding uhci_hcd */
	static inline struct uhci_hcd hcd_to_uhci(struct usb_hcd hcd)
	{
	return (struct uhci_hcd *) (hcd->hcd_priv);
	}
	static inline struct usb_hcd uhci_to_hcd(struct uhci_hcd uhci)
	{
	return container_of((void *) uhci, struct usb_hcd, hcd_priv);
	}

	#define uhci_dev(u) (uhci_to_hcd(u)->self.controller)

	struct urb_priv {
	struct list_head urb_list;

	struct urb *urb;

	struct uhci_qh qh; / QH for this URB */
	struct list_head td_list; /* P: urb->lock */

	unsigned fsbr : 1; /* URB turned on FSBR */
	unsigned fsbr_timeout : 1; /* URB timed out on FSBR */
	unsigned queued : 1; /* QH was queued (not linked in) */
	unsigned short_control_packet : 1; /* If we get a short packet during */
	/* a control transfer, retrigger */
	/* the status phase */

	unsigned long inserttime; /* In jiffies */
	unsigned long fsbrtime; /* In jiffies */

	struct list_head queue_list; /* P: uhci->frame_list_lock */
	};

	/*
	* Locking in uhci.c
	*
	* Almost everything relating to the hardware schedule and processing
	* of URBs is protected by uhci->lock. urb->status is protected by
	* urb->lock; that's the one exception.
	*
	* To prevent deadlocks, never lock uhci->lock while holding urb->lock.
	* The safe order of locking is:
	*
	* #1 uhci->lock
	* #2 urb->lock
	*/

	#endif