drivers/usb/core/hub.h

#ifndef __LINUX_HUB_H
#define __LINUX_HUB_H

/*
 * Hub protocol and driver data structures.
 *
 * Some of these are known to the "virtual root hub" code
 * in host controller drivers.
 */

#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/compiler.h>	/* likely()/unlikely() */

/*
 * Hub request types
 */

#define USB_RT_HUB	(USB_TYPE_CLASS | USB_RECIP_DEVICE)
#define USB_RT_PORT	(USB_TYPE_CLASS | USB_RECIP_OTHER)

/*
 * Hub class requests
 * See USB 2.0 spec Table 11-16
 */
#define HUB_CLEAR_TT_BUFFER	8
#define HUB_RESET_TT		9
#define HUB_GET_TT_STATE	10
#define HUB_STOP_TT		11

/*
 * Hub Class feature numbers
 * See USB 2.0 spec Table 11-17
 */
#define C_HUB_LOCAL_POWER	0
#define C_HUB_OVER_CURRENT	1

/*
 * Port feature numbers
 * See USB 2.0 spec Table 11-17
 */
#define USB_PORT_FEAT_CONNECTION	0
#define USB_PORT_FEAT_ENABLE		1
#define USB_PORT_FEAT_SUSPEND		2
#define USB_PORT_FEAT_OVER_CURRENT	3
#define USB_PORT_FEAT_RESET		4
#define USB_PORT_FEAT_POWER		8
#define USB_PORT_FEAT_LOWSPEED		9
#define USB_PORT_FEAT_HIGHSPEED		10
#define USB_PORT_FEAT_C_CONNECTION	16
#define USB_PORT_FEAT_C_ENABLE		17
#define USB_PORT_FEAT_C_SUSPEND		18
#define USB_PORT_FEAT_C_OVER_CURRENT	19
#define USB_PORT_FEAT_C_RESET		20
#define USB_PORT_FEAT_TEST              21
#define USB_PORT_FEAT_INDICATOR         22

/* 
 * Hub Status and Hub Change results
 * See USB 2.0 spec Table 11-19 and Table 11-20
 */
struct usb_port_status {
	__le16 wPortStatus;
	__le16 wPortChange;	
} __attribute__ ((packed));

/* 
 * wPortStatus bit field
 * See USB 2.0 spec Table 11-21
 */
#define USB_PORT_STAT_CONNECTION	0x0001
#define USB_PORT_STAT_ENABLE		0x0002
#define USB_PORT_STAT_SUSPEND		0x0004
#define USB_PORT_STAT_OVERCURRENT	0x0008
#define USB_PORT_STAT_RESET		0x0010
/* bits 5 to 7 are reserved */
#define USB_PORT_STAT_POWER		0x0100
#define USB_PORT_STAT_LOW_SPEED		0x0200
#define USB_PORT_STAT_HIGH_SPEED        0x0400
#define USB_PORT_STAT_TEST              0x0800
#define USB_PORT_STAT_INDICATOR         0x1000
/* bits 13 to 15 are reserved */

/* 
 * wPortChange bit field
 * See USB 2.0 spec Table 11-22
 * Bits 0 to 4 shown, bits 5 to 15 are reserved
 */
#define USB_PORT_STAT_C_CONNECTION	0x0001
#define USB_PORT_STAT_C_ENABLE		0x0002
#define USB_PORT_STAT_C_SUSPEND		0x0004
#define USB_PORT_STAT_C_OVERCURRENT	0x0008
#define USB_PORT_STAT_C_RESET		0x0010

/*
 * wHubCharacteristics (masks) 
 * See USB 2.0 spec Table 11-13, offset 3
 */
#define HUB_CHAR_LPSM		0x0003 /* D1 .. D0 */
#define HUB_CHAR_COMPOUND	0x0004 /* D2       */
#define HUB_CHAR_OCPM		0x0018 /* D4 .. D3 */
#define HUB_CHAR_TTTT           0x0060 /* D6 .. D5 */
#define HUB_CHAR_PORTIND        0x0080 /* D7       */

struct usb_hub_status {
	__le16 wHubStatus;
	__le16 wHubChange;
} __attribute__ ((packed));

/*
 * Hub Status & Hub Change bit masks
 * See USB 2.0 spec Table 11-19 and Table 11-20
 * Bits 0 and 1 for wHubStatus and wHubChange
 * Bits 2 to 15 are reserved for both
 */
#define HUB_STATUS_LOCAL_POWER	0x0001
#define HUB_STATUS_OVERCURRENT	0x0002
#define HUB_CHANGE_LOCAL_POWER	0x0001
#define HUB_CHANGE_OVERCURRENT	0x0002


/* 
 * Hub descriptor 
 * See USB 2.0 spec Table 11-13
 */

#define USB_DT_HUB			(USB_TYPE_CLASS | 0x09)
#define USB_DT_HUB_NONVAR_SIZE		7

struct usb_hub_descriptor {
	__u8  bDescLength;
	__u8  bDescriptorType;
	__u8  bNbrPorts;
	__u16 wHubCharacteristics;
	__u8  bPwrOn2PwrGood;
	__u8  bHubContrCurrent;
	    	/* add 1 bit for hub status change; round to bytes */
	__u8  DeviceRemovable[(USB_MAXCHILDREN + 1 + 7) / 8];
	__u8  PortPwrCtrlMask[(USB_MAXCHILDREN + 1 + 7) / 8];
} __attribute__ ((packed));


/* port indicator status selectors, tables 11-7 and 11-25 */
#define HUB_LED_AUTO	0
#define HUB_LED_AMBER	1
#define HUB_LED_GREEN	2
#define HUB_LED_OFF	3

enum hub_led_mode {
	INDICATOR_AUTO = 0,
	INDICATOR_CYCLE,
	/* software blinks for attention:  software, hardware, reserved */
	INDICATOR_GREEN_BLINK, INDICATOR_GREEN_BLINK_OFF,
	INDICATOR_AMBER_BLINK, INDICATOR_AMBER_BLINK_OFF,
	INDICATOR_ALT_BLINK, INDICATOR_ALT_BLINK_OFF
} __attribute__ ((packed));

struct usb_device;

/*
 * As of USB 2.0, full/low speed devices are segregated into trees.
 * One type grows from USB 1.1 host controllers (OHCI, UHCI etc).
 * The other type grows from high speed hubs when they connect to
 * full/low speed devices using "Transaction Translators" (TTs).
 *
 * TTs should only be known to the hub driver, and high speed bus
 * drivers (only EHCI for now).  They affect periodic scheduling and
 * sometimes control/bulk error recovery.
 */
struct usb_tt {
	struct usb_device	*hub;	/* upstream highspeed hub */
	int			multi;	/* true means one TT per port */

	/* for control/bulk error recovery (CLEAR_TT_BUFFER) */
	spinlock_t		lock;
	struct list_head	clear_list;	/* of usb_tt_clear */
	struct work_struct			kevent;
};

struct usb_tt_clear {
	struct list_head	clear_list;
	unsigned		tt;
	u16			devinfo;
};

extern void usb_hub_tt_clear_buffer (struct usb_device *dev, int pipe);

struct usb_hub {
	struct device		*intfdev;	/* the "interface" device */
	struct usb_device	*hdev;
	struct urb		*urb;		/* for interrupt polling pipe */

	/* buffer for urb ... with extra space in case of babble */
	char			(*buffer)[8];
	dma_addr_t		buffer_dma;	/* DMA address for buffer */
	union {
		struct usb_hub_status	hub;
		struct usb_port_status	port;
	}			*status;	/* buffer for status reports */

	int			error;		/* last reported error */
	int			nerrors;	/* track consecutive errors */

	struct list_head	event_list;	/* hubs w/data or errs ready */
	unsigned long		event_bits[1];	/* status change bitmask */
	unsigned long		change_bits[1];	/* ports with logical connect
							status change */
	unsigned long		busy_bits[1];	/* ports being reset */
#if USB_MAXCHILDREN > 31 /* 8*sizeof(unsigned long) - 1 */
#error event_bits[] is too short!
#endif

	struct usb_hub_descriptor *descriptor;	/* class descriptor */
	struct usb_tt		tt;		/* Transaction Translator */

	u8			power_budget;	/* in 2mA units; or zero */

	unsigned		quiescing:1;
	unsigned		activating:1;
	unsigned		resume_root_hub:1;

	unsigned		has_indicators:1;
	enum hub_led_mode	indicator[USB_MAXCHILDREN];
	struct work_struct	leds;
};

/* use this for low-powered root hubs */
static inline void
hub_set_power_budget (struct usb_device *hubdev, unsigned mA)
{
	struct usb_hub	*hub;

	hub = (struct usb_hub *)
		usb_get_intfdata (hubdev->actconfig->interface[0]);
	hub->power_budget = min(mA,(unsigned)500)/2;
}

#endif /* __LINUX_HUB_H */