Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 3057 insertions, 0 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
new file mode 100644
index 000000000000..fa0dc4f6de47
--- /dev/null
+++ b/drivers/usb/core/hub.c
@@ -0,0 +1,3057 @@
+/*
+ * USB hub driver.
+ *
+ * (C) Copyright 1999 Linus Torvalds
+ * (C) Copyright 1999 Johannes Erdfelt
+ * (C) Copyright 1999 Gregory P. Smith
+ * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
+ *
+ */
+
+#include <linux/config.h>
+#ifdef CONFIG_USB_DEBUG
+	#define DEBUG
+#else
+	#undef DEBUG
+#endif
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/completion.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/ioctl.h>
+#include <linux/usb.h>
+#include <linux/usbdevice_fs.h>
+
+#include <asm/semaphore.h>
+#include <asm/uaccess.h>
+#include <asm/byteorder.h>
+
+#include "usb.h"
+#include "hcd.h"
+#include "hub.h"
+
+/* Protect struct usb_device->state and ->children members
+ * Note: Both are also protected by ->serialize, except that ->state can
+ * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
+static DEFINE_SPINLOCK(device_state_lock);
+
+/* khubd's worklist and its lock */
+static DEFINE_SPINLOCK(hub_event_lock);
+static LIST_HEAD(hub_event_list);	/* List of hubs needing servicing */
+
+/* Wakes up khubd */
+static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
+
+static pid_t khubd_pid = 0;			/* PID of khubd */
+static DECLARE_COMPLETION(khubd_exited);
+
+/* cycle leds on hubs that aren't blinking for attention */
+static int blinkenlights = 0;
+module_param (blinkenlights, bool, S_IRUGO);
+MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
+
+/*
+ * As of 2.6.10 we introduce a new USB device initialization scheme which
+ * closely resembles the way Windows works.  Hopefully it will be compatible
+ * with a wider range of devices than the old scheme.  However some previously
+ * working devices may start giving rise to "device not accepting address"
+ * errors; if that happens the user can try the old scheme by adjusting the
+ * following module parameters.
+ *
+ * For maximum flexibility there are two boolean parameters to control the
+ * hub driver's behavior.  On the first initialization attempt, if the
+ * "old_scheme_first" parameter is set then the old scheme will be used,
+ * otherwise the new scheme is used.  If that fails and "use_both_schemes"
+ * is set, then the driver will make another attempt, using the other scheme.
+ */
+static int old_scheme_first = 0;
+module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(old_scheme_first,
+		 "start with the old device initialization scheme");
+
+static int use_both_schemes = 1;
+module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(use_both_schemes,
+		"try the other device initialization scheme if the "
+		"first one fails");
+
+
+#ifdef	DEBUG
+static inline char *portspeed (int portstatus)
+{
+	if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
+    		return "480 Mb/s";
+	else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
+		return "1.5 Mb/s";
+	else
+		return "12 Mb/s";
+}
+#endif
+
+/* Note that hdev or one of its children must be locked! */
+static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
+{
+	return usb_get_intfdata(hdev->actconfig->interface[0]);
+}
+
+/* USB 2.0 spec Section 11.24.4.5 */
+static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
+{
+	int i, ret;
+
+	for (i = 0; i < 3; i++) {
+		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
+			USB_DT_HUB << 8, 0, data, size,
+			USB_CTRL_GET_TIMEOUT);
+		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
+			return ret;
+	}
+	return -EINVAL;
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.1
+ */
+static int clear_hub_feature(struct usb_device *hdev, int feature)
+{
+	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.2
+ */
+static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
+{
+	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
+		NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.13
+ */
+static int set_port_feature(struct usb_device *hdev, int port1, int feature)
+{
+	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
+		NULL, 0, 1000);
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
+ * for info about using port indicators
+ */
+static void set_port_led(
+	struct usb_hub *hub,
+	int port1,
+	int selector
+)
+{
+	int status = set_port_feature(hub->hdev, (selector << 8) | port1,
+			USB_PORT_FEAT_INDICATOR);
+	if (status < 0)
+		dev_dbg (hub->intfdev,
+			"port %d indicator %s status %d\n",
+			port1,
+			({ char *s; switch (selector) {
+			case HUB_LED_AMBER: s = "amber"; break;
+			case HUB_LED_GREEN: s = "green"; break;
+			case HUB_LED_OFF: s = "off"; break;
+			case HUB_LED_AUTO: s = "auto"; break;
+			default: s = "??"; break;
+			}; s; }),
+			status);
+}
+
+#define	LED_CYCLE_PERIOD	((2*HZ)/3)
+
+static void led_work (void *__hub)
+{
+	struct usb_hub		*hub = __hub;
+	struct usb_device	*hdev = hub->hdev;
+	unsigned		i;
+	unsigned		changed = 0;
+	int			cursor = -1;
+
+	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
+		return;
+
+	for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
+		unsigned	selector, mode;
+
+		/* 30%-50% duty cycle */
+
+		switch (hub->indicator[i]) {
+		/* cycle marker */
+		case INDICATOR_CYCLE:
+			cursor = i;
+			selector = HUB_LED_AUTO;
+			mode = INDICATOR_AUTO;
+			break;
+		/* blinking green = sw attention */
+		case INDICATOR_GREEN_BLINK:
+			selector = HUB_LED_GREEN;
+			mode = INDICATOR_GREEN_BLINK_OFF;
+			break;
+		case INDICATOR_GREEN_BLINK_OFF:
+			selector = HUB_LED_OFF;
+			mode = INDICATOR_GREEN_BLINK;
+			break;
+		/* blinking amber = hw attention */
+		case INDICATOR_AMBER_BLINK:
+			selector = HUB_LED_AMBER;
+			mode = INDICATOR_AMBER_BLINK_OFF;
+			break;
+		case INDICATOR_AMBER_BLINK_OFF:
+			selector = HUB_LED_OFF;
+			mode = INDICATOR_AMBER_BLINK;
+			break;
+		/* blink green/amber = reserved */
+		case INDICATOR_ALT_BLINK:
+			selector = HUB_LED_GREEN;
+			mode = INDICATOR_ALT_BLINK_OFF;
+			break;
+		case INDICATOR_ALT_BLINK_OFF:
+			selector = HUB_LED_AMBER;
+			mode = INDICATOR_ALT_BLINK;
+			break;
+		default:
+			continue;
+		}
+		if (selector != HUB_LED_AUTO)
+			changed = 1;
+		set_port_led(hub, i + 1, selector);
+		hub->indicator[i] = mode;
+	}
+	if (!changed && blinkenlights) {
+		cursor++;
+		cursor %= hub->descriptor->bNbrPorts;
+		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
+		hub->indicator[cursor] = INDICATOR_CYCLE;
+		changed++;
+	}
+	if (changed)
+		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
+}
+
+/* use a short timeout for hub/port status fetches */
+#define	USB_STS_TIMEOUT		1000
+#define	USB_STS_RETRIES		5
+
+/*
+ * USB 2.0 spec Section 11.24.2.6
+ */
+static int get_hub_status(struct usb_device *hdev,
+		struct usb_hub_status *data)
+{
+	int i, status = -ETIMEDOUT;
+
+	for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
+		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
+			data, sizeof(*data), USB_STS_TIMEOUT);
+	}
+	return status;
+}
+
+/*
+ * USB 2.0 spec Section 11.24.2.7
+ */
+static int get_port_status(struct usb_device *hdev, int port1,
+		struct usb_port_status *data)
+{
+	int i, status = -ETIMEDOUT;
+
+	for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
+		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
+			data, sizeof(*data), USB_STS_TIMEOUT);
+	}
+	return status;
+}
+
+static void kick_khubd(struct usb_hub *hub)
+{
+	unsigned long	flags;
+
+	spin_lock_irqsave(&hub_event_lock, flags);
+	if (list_empty(&hub->event_list)) {
+		list_add_tail(&hub->event_list, &hub_event_list);
+		wake_up(&khubd_wait);
+	}
+	spin_unlock_irqrestore(&hub_event_lock, flags);
+}
+
+void usb_kick_khubd(struct usb_device *hdev)
+{
+	kick_khubd(hdev_to_hub(hdev));
+}
+
+
+/* completion function, fires on port status changes and various faults */
+static void hub_irq(struct urb *urb, struct pt_regs *regs)
+{
+	struct usb_hub *hub = (struct usb_hub *)urb->context;
+	int status;
+	int i;
+	unsigned long bits;
+
+	switch (urb->status) {
+	case -ENOENT:		/* synchronous unlink */
+	case -ECONNRESET:	/* async unlink */
+	case -ESHUTDOWN:	/* hardware going away */
+		return;
+
+	default:		/* presumably an error */
+		/* Cause a hub reset after 10 consecutive errors */
+		dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
+		if ((++hub->nerrors < 10) || hub->error)
+			goto resubmit;
+		hub->error = urb->status;
+		/* FALL THROUGH */
+	
+	/* let khubd handle things */
+	case 0:			/* we got data:  port status changed */
+		bits = 0;
+		for (i = 0; i < urb->actual_length; ++i)
+			bits |= ((unsigned long) ((*hub->buffer)[i]))
+					<< (i*8);
+		hub->event_bits[0] = bits;
+		break;
+	}
+
+	hub->nerrors = 0;
+
+	/* Something happened, let khubd figure it out */
+	kick_khubd(hub);
+
+resubmit:
+	if (hub->quiescing)
+		return;
+
+	if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
+			&& status != -ENODEV && status != -EPERM)
+		dev_err (hub->intfdev, "resubmit --> %d\n", status);
+}
+
+/* USB 2.0 spec Section 11.24.2.3 */
+static inline int
+hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
+{
+	return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
+			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
+			       tt, NULL, 0, 1000);
+}
+
+/*
+ * enumeration blocks khubd for a long time. we use keventd instead, since
+ * long blocking there is the exception, not the rule.  accordingly, HCDs
+ * talking to TTs must queue control transfers (not just bulk and iso), so
+ * both can talk to the same hub concurrently.
+ */
+static void hub_tt_kevent (void *arg)
+{
+	struct usb_hub		*hub = arg;
+	unsigned long		flags;
+
+	spin_lock_irqsave (&hub->tt.lock, flags);
+	while (!list_empty (&hub->tt.clear_list)) {
+		struct list_head	*temp;
+		struct usb_tt_clear	*clear;
+		struct usb_device	*hdev = hub->hdev;
+		int			status;
+
+		temp = hub->tt.clear_list.next;
+		clear = list_entry (temp, struct usb_tt_clear, clear_list);
+		list_del (&clear->clear_list);
+
+		/* drop lock so HCD can concurrently report other TT errors */
+		spin_unlock_irqrestore (&hub->tt.lock, flags);
+		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
+		spin_lock_irqsave (&hub->tt.lock, flags);
+
+		if (status)
+			dev_err (&hdev->dev,
+				"clear tt %d (%04x) error %d\n",
+				clear->tt, clear->devinfo, status);
+		kfree (clear);
+	}
+	spin_unlock_irqrestore (&hub->tt.lock, flags);
+}
+
+/**
+ * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
+ * @udev: the device whose split transaction failed
+ * @pipe: identifies the endpoint of the failed transaction
+ *
+ * High speed HCDs use this to tell the hub driver that some split control or
+ * bulk transaction failed in a way that requires clearing internal state of
+ * a transaction translator.  This is normally detected (and reported) from
+ * interrupt context.
+ *
+ * It may not be possible for that hub to handle additional full (or low)
+ * speed transactions until that state is fully cleared out.
+ */
+void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
+{
+	struct usb_tt		*tt = udev->tt;
+	unsigned long		flags;
+	struct usb_tt_clear	*clear;
+
+	/* we've got to cope with an arbitrary number of pending TT clears,
+	 * since each TT has "at least two" buffers that can need it (and
+	 * there can be many TTs per hub).  even if they're uncommon.
+	 */
+	if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
+		dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
+		/* FIXME recover somehow ... RESET_TT? */
+		return;
+	}
+
+	/* info that CLEAR_TT_BUFFER needs */
+	clear->tt = tt->multi ? udev->ttport : 1;
+	clear->devinfo = usb_pipeendpoint (pipe);
+	clear->devinfo |= udev->devnum << 4;
+	clear->devinfo |= usb_pipecontrol (pipe)
+			? (USB_ENDPOINT_XFER_CONTROL << 11)
+			: (USB_ENDPOINT_XFER_BULK << 11);
+	if (usb_pipein (pipe))
+		clear->devinfo |= 1 << 15;
+	
+	/* tell keventd to clear state for this TT */
+	spin_lock_irqsave (&tt->lock, flags);
+	list_add_tail (&clear->clear_list, &tt->clear_list);
+	schedule_work (&tt->kevent);
+	spin_unlock_irqrestore (&tt->lock, flags);
+}
+
+static void hub_power_on(struct usb_hub *hub)
+{
+	int port1;
+
+	/* if hub supports power switching, enable power on each port */
+	if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
+		dev_dbg(hub->intfdev, "enabling power on all ports\n");
+		for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
+			set_port_feature(hub->hdev, port1,
+					USB_PORT_FEAT_POWER);
+	}
+
+	/* Wait for power to be enabled */
+	msleep(hub->descriptor->bPwrOn2PwrGood * 2);
+}
+
+static void hub_quiesce(struct usb_hub *hub)
+{
+	/* stop khubd and related activity */
+	hub->quiescing = 1;
+	usb_kill_urb(hub->urb);
+	if (hub->has_indicators)
+		cancel_delayed_work(&hub->leds);
+	if (hub->has_indicators || hub->tt.hub)
+		flush_scheduled_work();
+}
+
+static void hub_activate(struct usb_hub *hub)
+{
+	int	status;
+
+	hub->quiescing = 0;
+	hub->activating = 1;
+	status = usb_submit_urb(hub->urb, GFP_NOIO);
+	if (status < 0)
+		dev_err(hub->intfdev, "activate --> %d\n", status);
+	if (hub->has_indicators && blinkenlights)
+		schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
+
+	/* scan all ports ASAP */
+	kick_khubd(hub);
+}
+
+static int hub_hub_status(struct usb_hub *hub,
+		u16 *status, u16 *change)
+{
+	int ret;
+
+	ret = get_hub_status(hub->hdev, &hub->status->hub);
+	if (ret < 0)
+		dev_err (hub->intfdev,
+			"%s failed (err = %d)\n", __FUNCTION__, ret);
+	else {
+		*status = le16_to_cpu(hub->status->hub.wHubStatus);
+		*change = le16_to_cpu(hub->status->hub.wHubChange); 
+		ret = 0;
+	}
+	return ret;
+}
+
+static int hub_configure(struct usb_hub *hub,
+	struct usb_endpoint_descriptor *endpoint)
+{
+	struct usb_device *hdev = hub->hdev;
+	struct device *hub_dev = hub->intfdev;
+	u16 hubstatus, hubchange;
+	unsigned int pipe;
+	int maxp, ret;
+	char *message;
+
+	hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
+			&hub->buffer_dma);
+	if (!hub->buffer) {
+		message = "can't allocate hub irq buffer";
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
+	if (!hub->status) {
+		message = "can't kmalloc hub status buffer";
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
+	if (!hub->descriptor) {
+		message = "can't kmalloc hub descriptor";
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	/* Request the entire hub descriptor.
+	 * hub->descriptor can handle USB_MAXCHILDREN ports,
+	 * but the hub can/will return fewer bytes here.
+	 */
+	ret = get_hub_descriptor(hdev, hub->descriptor,
+			sizeof(*hub->descriptor));
+	if (ret < 0) {
+		message = "can't read hub descriptor";
+		goto fail;
+	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
+		message = "hub has too many ports!";
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	hdev->maxchild = hub->descriptor->bNbrPorts;
+	dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
+		(hdev->maxchild == 1) ? "" : "s");
+
+	le16_to_cpus(&hub->descriptor->wHubCharacteristics);
+
+	if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) {
+		int	i;
+		char	portstr [USB_MAXCHILDREN + 1];
+
+		for (i = 0; i < hdev->maxchild; i++)
+			portstr[i] = hub->descriptor->DeviceRemovable
+				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
+				? 'F' : 'R';
+		portstr[hdev->maxchild] = 0;
+		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
+	} else
+		dev_dbg(hub_dev, "standalone hub\n");
+
+	switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) {
+		case 0x00:
+			dev_dbg(hub_dev, "ganged power switching\n");
+			break;
+		case 0x01:
+			dev_dbg(hub_dev, "individual port power switching\n");
+			break;
+		case 0x02:
+		case 0x03:
+			dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
+			break;
+	}
+
+	switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) {
+		case 0x00:
+			dev_dbg(hub_dev, "global over-current protection\n");
+			break;
+		case 0x08:
+			dev_dbg(hub_dev, "individual port over-current protection\n");
+			break;
+		case 0x10:
+		case 0x18:
+			dev_dbg(hub_dev, "no over-current protection\n");
+                        break;
+	}
+
+	spin_lock_init (&hub->tt.lock);
+	INIT_LIST_HEAD (&hub->tt.clear_list);
+	INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
+	switch (hdev->descriptor.bDeviceProtocol) {
+		case 0:
+			break;
+		case 1:
+			dev_dbg(hub_dev, "Single TT\n");
+			hub->tt.hub = hdev;
+			break;
+		case 2:
+			ret = usb_set_interface(hdev, 0, 1);
+			if (ret == 0) {
+				dev_dbg(hub_dev, "TT per port\n");
+				hub->tt.multi = 1;
+			} else
+				dev_err(hub_dev, "Using single TT (err %d)\n",
+					ret);
+			hub->tt.hub = hdev;
+			break;
+		default:
+			dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
+				hdev->descriptor.bDeviceProtocol);
+			break;
+	}
+
+	switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
+		case 0x00:
+			if (hdev->descriptor.bDeviceProtocol != 0)
+				dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
+			break;
+		case 0x20:
+			dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
+			break;
+		case 0x40:
+			dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
+			break;
+		case 0x60:
+			dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
+			break;
+	}
+
+	/* probe() zeroes hub->indicator[] */
+	if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) {
+		hub->has_indicators = 1;
+		dev_dbg(hub_dev, "Port indicators are supported\n");
+	}
+
+	dev_dbg(hub_dev, "power on to power good time: %dms\n",
+		hub->descriptor->bPwrOn2PwrGood * 2);
+
+	/* power budgeting mostly matters with bus-powered hubs,
+	 * and battery-powered root hubs (may provide just 8 mA).
+	 */
+	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
+	if (ret < 0) {
+		message = "can't get hub status";
+		goto fail;
+	}
+	cpu_to_le16s(&hubstatus);
+	if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
+		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
+			hub->descriptor->bHubContrCurrent);
+		hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
+					/ 2;
+		dev_dbg(hub_dev, "%dmA bus power budget for children\n",
+			hub->power_budget * 2);
+	}
+
+
+	ret = hub_hub_status(hub, &hubstatus, &hubchange);
+	if (ret < 0) {
+		message = "can't get hub status";
+		goto fail;
+	}
+
+	/* local power status reports aren't always correct */
+	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
+		dev_dbg(hub_dev, "local power source is %s\n",
+			(hubstatus & HUB_STATUS_LOCAL_POWER)
+			? "lost (inactive)" : "good");
+
+	if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0)
+		dev_dbg(hub_dev, "%sover-current condition exists\n",
+			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
+
+	/* set up the interrupt endpoint */
+	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
+	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
+
+	if (maxp > sizeof(*hub->buffer))
+		maxp = sizeof(*hub->buffer);
+
+	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!hub->urb) {
+		message = "couldn't allocate interrupt urb";
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
+		hub, endpoint->bInterval);
+	hub->urb->transfer_dma = hub->buffer_dma;
+	hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+	/* maybe cycle the hub leds */
+	if (hub->has_indicators && blinkenlights)
+		hub->indicator [0] = INDICATOR_CYCLE;
+
+	hub_power_on(hub);
+	hub_activate(hub);
+	return 0;
+
+fail:
+	dev_err (hub_dev, "config failed, %s (err %d)\n",
+			message, ret);
+	/* hub_disconnect() frees urb and descriptor */
+	return ret;
+}
+
+static unsigned highspeed_hubs;
+
+static void hub_disconnect(struct usb_interface *intf)
+{
+	struct usb_hub *hub = usb_get_intfdata (intf);
+	struct usb_device *hdev;
+
+	if (!hub)
+		return;
+	hdev = hub->hdev;
+
+	if (hdev->speed == USB_SPEED_HIGH)
+		highspeed_hubs--;
+
+	usb_set_intfdata (intf, NULL);
+
+	hub_quiesce(hub);
+	usb_free_urb(hub->urb);
+	hub->urb = NULL;
+
+	spin_lock_irq(&hub_event_lock);
+	list_del_init(&hub->event_list);
+	spin_unlock_irq(&hub_event_lock);
+
+	if (hub->descriptor) {
+		kfree(hub->descriptor);
+		hub->descriptor = NULL;
+	}
+
+	if (hub->status) {
+		kfree(hub->status);
+		hub->status = NULL;
+	}
+
+	if (hub->buffer) {
+		usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
+				hub->buffer_dma);
+		hub->buffer = NULL;
+	}
+
+	/* Free the memory */
+	kfree(hub);
+}
+
+static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
+{
+	struct usb_host_interface *desc;
+	struct usb_endpoint_descriptor *endpoint;
+	struct usb_device *hdev;
+	struct usb_hub *hub;
+
+	desc = intf->cur_altsetting;
+	hdev = interface_to_usbdev(intf);
+
+	/* Some hubs have a subclass of 1, which AFAICT according to the */
+	/*  specs is not defined, but it works */
+	if ((desc->desc.bInterfaceSubClass != 0) &&
+	    (desc->desc.bInterfaceSubClass != 1)) {
+descriptor_error:
+		dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
+		return -EIO;
+	}
+
+	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
+	if (desc->desc.bNumEndpoints != 1)
+		goto descriptor_error;
+
+	endpoint = &desc->endpoint[0].desc;
+
+	/* Output endpoint? Curiouser and curiouser.. */
+	if (!(endpoint->bEndpointAddress & USB_DIR_IN))
+		goto descriptor_error;
+
+	/* If it's not an interrupt endpoint, we'd better punt! */
+	if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+			!= USB_ENDPOINT_XFER_INT)
+		goto descriptor_error;
+
+	/* We found a hub */
+	dev_info (&intf->dev, "USB hub found\n");
+
+	hub = kmalloc(sizeof(*hub), GFP_KERNEL);
+	if (!hub) {
+		dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
+		return -ENOMEM;
+	}
+
+	memset(hub, 0, sizeof(*hub));
+
+	INIT_LIST_HEAD(&hub->event_list);
+	hub->intfdev = &intf->dev;
+	hub->hdev = hdev;
+	INIT_WORK(&hub->leds, led_work, hub);
+
+	usb_set_intfdata (intf, hub);
+
+	if (hdev->speed == USB_SPEED_HIGH)
+		highspeed_hubs++;
+
+	if (hub_configure(hub, endpoint) >= 0)
+		return 0;
+
+	hub_disconnect (intf);
+	return -ENODEV;
+}
+
+static int
+hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
+{
+	struct usb_device *hdev = interface_to_usbdev (intf);
+
+	/* assert ifno == 0 (part of hub spec) */
+	switch (code) {
+	case USBDEVFS_HUB_PORTINFO: {
+		struct usbdevfs_hub_portinfo *info = user_data;
+		int i;
+
+		spin_lock_irq(&device_state_lock);
+		if (hdev->devnum <= 0)
+			info->nports = 0;
+		else {
+			info->nports = hdev->maxchild;
+			for (i = 0; i < info->nports; i++) {
+				if (hdev->children[i] == NULL)
+					info->port[i] = 0;
+				else
+					info->port[i] =
+						hdev->children[i]->devnum;
+			}
+		}
+		spin_unlock_irq(&device_state_lock);
+
+		return info->nports + 1;
+		}
+
+	default:
+		return -ENOSYS;
+	}
+}
+
+/* caller has locked the hub device */
+static void hub_pre_reset(struct usb_hub *hub)
+{
+	struct usb_device *hdev = hub->hdev;
+	int i;
+
+	for (i = 0; i < hdev->maxchild; ++i) {
+		if (hdev->children[i])
+			usb_disconnect(&hdev->children[i]);
+	}
+	hub_quiesce(hub);
+}
+
+/* caller has locked the hub device */
+static void hub_post_reset(struct usb_hub *hub)
+{
+	hub_activate(hub);
+	hub_power_on(hub);
+}
+
+
+/* grab device/port lock, returning index of that port (zero based).
+ * protects the upstream link used by this device from concurrent
+ * tree operations like suspend, resume, reset, and disconnect, which
+ * apply to everything downstream of a given port.
+ */
+static int locktree(struct usb_device *udev)
+{
+	int			t;
+	struct usb_device	*hdev;
+
+	if (!udev)
+		return -ENODEV;
+
+	/* root hub is always the first lock in the series */
+	hdev = udev->parent;
+	if (!hdev) {
+		usb_lock_device(udev);
+		return 0;
+	}
+
+	/* on the path from root to us, lock everything from
+	 * top down, dropping parent locks when not needed
+	 */
+	t = locktree(hdev);
+	if (t < 0)
+		return t;
+	for (t = 0; t < hdev->maxchild; t++) {
+		if (hdev->children[t] == udev) {
+			/* everything is fail-fast once disconnect
+			 * processing starts
+			 */
+			if (udev->state == USB_STATE_NOTATTACHED)
+				break;
+
+			/* when everyone grabs locks top->bottom,
+			 * non-overlapping work may be concurrent
+			 */
+			down(&udev->serialize);
+			up(&hdev->serialize);
+			return t + 1;
+		}
+	}
+	usb_unlock_device(hdev);
+	return -ENODEV;
+}
+
+static void recursively_mark_NOTATTACHED(struct usb_device *udev)
+{
+	int i;
+
+	for (i = 0; i < udev->maxchild; ++i) {
+		if (udev->children[i])
+			recursively_mark_NOTATTACHED(udev->children[i]);
+	}
+	udev->state = USB_STATE_NOTATTACHED;
+}
+
+/**
+ * usb_set_device_state - change a device's current state (usbcore, hcds)
+ * @udev: pointer to device whose state should be changed
+ * @new_state: new state value to be stored
+ *
+ * udev->state is _not_ fully protected by the device lock.  Although
+ * most transitions are made only while holding the lock, the state can
+ * can change to USB_STATE_NOTATTACHED at almost any time.  This
+ * is so that devices can be marked as disconnected as soon as possible,
+ * without having to wait for any semaphores to be released.  As a result,
+ * all changes to any device's state must be protected by the
+ * device_state_lock spinlock.
+ *
+ * Once a device has been added to the device tree, all changes to its state
+ * should be made using this routine.  The state should _not_ be set directly.
+ *
+ * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
+ * Otherwise udev->state is set to new_state, and if new_state is
+ * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
+ * to USB_STATE_NOTATTACHED.
+ */
+void usb_set_device_state(struct usb_device *udev,
+		enum usb_device_state new_state)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&device_state_lock, flags);
+	if (udev->state == USB_STATE_NOTATTACHED)
+		;	/* do nothing */
+	else if (new_state != USB_STATE_NOTATTACHED)
+		udev->state = new_state;
+	else
+		recursively_mark_NOTATTACHED(udev);
+	spin_unlock_irqrestore(&device_state_lock, flags);
+}
+EXPORT_SYMBOL(usb_set_device_state);
+
+
+static void choose_address(struct usb_device *udev)
+{
+	int		devnum;
+	struct usb_bus	*bus = udev->bus;
+
+	/* If khubd ever becomes multithreaded, this will need a lock */
+
+	/* Try to allocate the next devnum beginning at bus->devnum_next. */
+	devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
+			bus->devnum_next);
+	if (devnum >= 128)
+		devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
+
+	bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
+
+	if (devnum < 128) {
+		set_bit(devnum, bus->devmap.devicemap);
+		udev->devnum = devnum;
+	}
+}
+
+static void release_address(struct usb_device *udev)
+{
+	if (udev->devnum > 0) {
+		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
+		udev->devnum = -1;
+	}
+}
+
+/**
+ * usb_disconnect - disconnect a device (usbcore-internal)
+ * @pdev: pointer to device being disconnected
+ * Context: !in_interrupt ()
+ *
+ * Something got disconnected. Get rid of it and all of its children.
+ *
+ * If *pdev is a normal device then the parent hub must already be locked.
+ * If *pdev is a root hub then this routine will acquire the
+ * usb_bus_list_lock on behalf of the caller.
+ *
+ * Only hub drivers (including virtual root hub drivers for host
+ * controllers) should ever call this.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ */
+void usb_disconnect(struct usb_device **pdev)
+{
+	struct usb_device	*udev = *pdev;
+	int			i;
+
+	if (!udev) {
+		pr_debug ("%s nodev\n", __FUNCTION__);
+		return;
+	}
+
+	/* mark the device as inactive, so any further urb submissions for
+	 * this device (and any of its children) will fail immediately.
+	 * this quiesces everyting except pending urbs.
+	 */
+	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+
+	/* lock the bus list on behalf of HCDs unregistering their root hubs */
+	if (!udev->parent) {
+		down(&usb_bus_list_lock);
+		usb_lock_device(udev);
+	} else
+		down(&udev->serialize);
+
+	dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
+
+	/* Free up all the children before we remove this device */
+	for (i = 0; i < USB_MAXCHILDREN; i++) {
+		if (udev->children[i])
+			usb_disconnect(&udev->children[i]);
+	}
+
+	/* deallocate hcd/hardware state ... nuking all pending urbs and
+	 * cleaning up all state associated with the current configuration
+	 * so that the hardware is now fully quiesced.
+	 */
+	usb_disable_device(udev, 0);
+
+	/* Free the device number, remove the /proc/bus/usb entry and
+	 * the sysfs attributes, and delete the parent's children[]
+	 * (or root_hub) pointer.
+	 */
+	dev_dbg (&udev->dev, "unregistering device\n");
+	release_address(udev);
+	usbfs_remove_device(udev);
+	usb_remove_sysfs_dev_files(udev);
+
+	/* Avoid races with recursively_mark_NOTATTACHED() */
+	spin_lock_irq(&device_state_lock);
+	*pdev = NULL;
+	spin_unlock_irq(&device_state_lock);
+
+	if (!udev->parent) {
+		usb_unlock_device(udev);
+		up(&usb_bus_list_lock);
+	} else
+		up(&udev->serialize);
+
+	device_unregister(&udev->dev);
+}
+
+static int choose_configuration(struct usb_device *udev)
+{
+	int c, i;
+
+	/* NOTE: this should interact with hub power budgeting */
+
+	c = udev->config[0].desc.bConfigurationValue;
+	if (udev->descriptor.bNumConfigurations != 1) {
+		for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
+			struct usb_interface_descriptor	*desc;
+
+			/* heuristic:  Linux is more likely to have class
+			 * drivers, so avoid vendor-specific interfaces.
+			 */
+			desc = &udev->config[i].intf_cache[0]
+					->altsetting->desc;
+			if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
+				continue;
+			/* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
+			 * MSFT needs this to be the first config; never use
+			 * it as the default unless Linux has host-side RNDIS.
+			 * A second config would ideally be CDC-Ethernet, but
+			 * may instead be the "vendor specific" CDC subset
+			 * long used by ARM Linux for sa1100 or pxa255.
+			 */
+			if (desc->bInterfaceClass == USB_CLASS_COMM
+					&& desc->bInterfaceSubClass == 2
+					&& desc->bInterfaceProtocol == 0xff) {
+				c = udev->config[1].desc.bConfigurationValue;
+				continue;
+			}
+			c = udev->config[i].desc.bConfigurationValue;
+			break;
+		}
+		dev_info(&udev->dev,
+			"configuration #%d chosen from %d choices\n",
+			c, udev->descriptor.bNumConfigurations);
+	}
+	return c;
+}
+
+#ifdef DEBUG
+static void show_string(struct usb_device *udev, char *id, char *string)
+{
+	if (!string)
+		return;
+	dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
+}
+
+#else
+static inline void show_string(struct usb_device *udev, char *id, char *string)
+{}
+#endif
+
+static void get_string(struct usb_device *udev, char **string, int index)
+{
+	char *buf;
+
+	if (!index)
+		return;
+	buf = kmalloc(256, GFP_KERNEL);
+	if (!buf)
+		return;
+	if (usb_string(udev, index, buf, 256) > 0)
+		*string = buf;
+	else
+		kfree(buf);
+}
+
+
+#ifdef	CONFIG_USB_OTG
+#include "otg_whitelist.h"
+#endif
+
+/**
+ * usb_new_device - perform initial device setup (usbcore-internal)
+ * @udev: newly addressed device (in ADDRESS state)
+ *
+ * This is called with devices which have been enumerated, but not yet
+ * configured.  The device descriptor is available, but not descriptors
+ * for any device configuration.  The caller must have locked udev and
+ * either the parent hub (if udev is a normal device) or else the
+ * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
+ * udev has already been installed, but udev is not yet visible through
+ * sysfs or other filesystem code.
+ *
+ * Returns 0 for success (device is configured and listed, with its
+ * interfaces, in sysfs); else a negative errno value.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ *
+ * Only the hub driver should ever call this; root hub registration
+ * uses it indirectly.
+ */
+int usb_new_device(struct usb_device *udev)
+{
+	int err;
+	int c;
+
+	err = usb_get_configuration(udev);
+	if (err < 0) {
+		dev_err(&udev->dev, "can't read configurations, error %d\n",
+			err);
+		goto fail;
+	}
+
+	/* read the standard strings and cache them if present */
+	get_string(udev, &udev->product, udev->descriptor.iProduct);
+	get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
+	get_string(udev, &udev->serial, udev->descriptor.iSerialNumber);
+
+	/* Tell the world! */
+	dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
+			"SerialNumber=%d\n",
+			udev->descriptor.iManufacturer,
+			udev->descriptor.iProduct,
+			udev->descriptor.iSerialNumber);
+	show_string(udev, "Product", udev->product);
+	show_string(udev, "Manufacturer", udev->manufacturer);
+	show_string(udev, "SerialNumber", udev->serial);
+
+#ifdef	CONFIG_USB_OTG
+	/*
+	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
+	 * to wake us after we've powered off VBUS; and HNP, switching roles
+	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
+	 */
+	if (!udev->bus->is_b_host
+			&& udev->config
+			&& udev->parent == udev->bus->root_hub) {
+		struct usb_otg_descriptor	*desc = 0;
+		struct usb_bus			*bus = udev->bus;
+
+		/* descriptor may appear anywhere in config */
+		if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
+					le16_to_cpu(udev->config[0].desc.wTotalLength),
+					USB_DT_OTG, (void **) &desc) == 0) {
+			if (desc->bmAttributes & USB_OTG_HNP) {
+				unsigned		port1;
+				struct usb_device	*root = udev->parent;
+				
+				for (port1 = 1; port1 <= root->maxchild;
+						port1++) {
+					if (root->children[port1-1] == udev)
+						break;
+				}
+
+				dev_info(&udev->dev,
+					"Dual-Role OTG device on %sHNP port\n",
+					(port1 == bus->otg_port)
+						? "" : "non-");
+
+				/* enable HNP before suspend, it's simpler */
+				if (port1 == bus->otg_port)
+					bus->b_hnp_enable = 1;
+				err = usb_control_msg(udev,
+					usb_sndctrlpipe(udev, 0),
+					USB_REQ_SET_FEATURE, 0,
+					bus->b_hnp_enable
+						? USB_DEVICE_B_HNP_ENABLE
+						: USB_DEVICE_A_ALT_HNP_SUPPORT,
+					0, NULL, 0, USB_CTRL_SET_TIMEOUT);
+				if (err < 0) {
+					/* OTG MESSAGE: report errors here,
+					 * customize to match your product.
+					 */
+					dev_info(&udev->dev,
+						"can't set HNP mode; %d\n",
+						err);
+					bus->b_hnp_enable = 0;
+				}
+			}
+		}
+	}
+
+	if (!is_targeted(udev)) {
+
+		/* Maybe it can talk to us, though we can't talk to it.
+		 * (Includes HNP test device.)
+		 */
+		if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
+			static int __usb_suspend_device (struct usb_device *,
+						int port1, pm_message_t state);
+			err = __usb_suspend_device(udev,
+					udev->bus->otg_port,
+					PMSG_SUSPEND);
+			if (err < 0)
+				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
+		}
+		err = -ENODEV;
+		goto fail;
+	}
+#endif
+
+	/* put device-specific files into sysfs */
+	err = device_add (&udev->dev);
+	if (err) {
+		dev_err(&udev->dev, "can't device_add, error %d\n", err);
+		goto fail;
+	}
+	usb_create_sysfs_dev_files (udev);
+
+	/* choose and set the configuration. that registers the interfaces
+	 * with the driver core, and lets usb device drivers bind to them.
+	 */
+	c = choose_configuration(udev);
+	if (c < 0)
+		dev_warn(&udev->dev,
+				"can't choose an initial configuration\n");
+	else {
+		err = usb_set_configuration(udev, c);
+		if (err) {
+			dev_err(&udev->dev, "can't set config #%d, error %d\n",
+					c, err);
+			usb_remove_sysfs_dev_files(udev);
+			device_del(&udev->dev);
+			goto fail;
+		}
+	}
+
+	/* USB device state == configured ... usable */
+
+	/* add a /proc/bus/usb entry */
+	usbfs_add_device(udev);
+	return 0;
+
+fail:
+	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+	return err;
+}
+
+
+static int hub_port_status(struct usb_hub *hub, int port1,
+			       u16 *status, u16 *change)
+{
+	int ret;
+
+	ret = get_port_status(hub->hdev, port1, &hub->status->port);
+	if (ret < 0)
+		dev_err (hub->intfdev,
+			"%s failed (err = %d)\n", __FUNCTION__, ret);
+	else {
+		*status = le16_to_cpu(hub->status->port.wPortStatus);
+		*change = le16_to_cpu(hub->status->port.wPortChange); 
+		ret = 0;
+	}
+	return ret;
+}
+
+#define PORT_RESET_TRIES	5
+#define SET_ADDRESS_TRIES	2
+#define GET_DESCRIPTOR_TRIES	2
+#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
+#define USE_NEW_SCHEME(i)	((i) / 2 == old_scheme_first)
+
+#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
+#define HUB_SHORT_RESET_TIME	10
+#define HUB_LONG_RESET_TIME	200
+#define HUB_RESET_TIMEOUT	500
+
+static int hub_port_wait_reset(struct usb_hub *hub, int port1,
+				struct usb_device *udev, unsigned int delay)
+{
+	int delay_time, ret;
+	u16 portstatus;
+	u16 portchange;
+
+	for (delay_time = 0;
+			delay_time < HUB_RESET_TIMEOUT;
+			delay_time += delay) {
+		/* wait to give the device a chance to reset */
+		msleep(delay);
+
+		/* read and decode port status */
+		ret = hub_port_status(hub, port1, &portstatus, &portchange);
+		if (ret < 0)
+			return ret;
+
+		/* Device went away? */
+		if (!(portstatus & USB_PORT_STAT_CONNECTION))
+			return -ENOTCONN;
+
+		/* bomb out completely if something weird happened */
+		if ((portchange & USB_PORT_STAT_C_CONNECTION))
+			return -EINVAL;
+
+		/* if we`ve finished resetting, then break out of the loop */
+		if (!(portstatus & USB_PORT_STAT_RESET) &&
+		    (portstatus & USB_PORT_STAT_ENABLE)) {
+			if (portstatus & USB_PORT_STAT_HIGH_SPEED)
+				udev->speed = USB_SPEED_HIGH;
+			else if (portstatus & USB_PORT_STAT_LOW_SPEED)
+				udev->speed = USB_SPEED_LOW;
+			else
+				udev->speed = USB_SPEED_FULL;
+			return 0;
+		}
+
+		/* switch to the long delay after two short delay failures */
+		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
+			delay = HUB_LONG_RESET_TIME;
+
+		dev_dbg (hub->intfdev,
+			"port %d not reset yet, waiting %dms\n",
+			port1, delay);
+	}
+
+	return -EBUSY;
+}
+
+static int hub_port_reset(struct usb_hub *hub, int port1,
+				struct usb_device *udev, unsigned int delay)
+{
+	int i, status;
+
+	/* Reset the port */
+	for (i = 0; i < PORT_RESET_TRIES; i++) {
+		status = set_port_feature(hub->hdev,
+				port1, USB_PORT_FEAT_RESET);
+		if (status)
+			dev_err(hub->intfdev,
+					"cannot reset port %d (err = %d)\n",
+					port1, status);
+		else {
+			status = hub_port_wait_reset(hub, port1, udev, delay);
+			if (status)
+				dev_dbg(hub->intfdev,
+						"port_wait_reset: err = %d\n",
+						status);
+		}
+
+		/* return on disconnect or reset */
+		switch (status) {
+		case 0:
+			/* TRSTRCY = 10 ms */
+			msleep(10);
+			/* FALL THROUGH */
+		case -ENOTCONN:
+		case -ENODEV:
+			clear_port_feature(hub->hdev,
+				port1, USB_PORT_FEAT_C_RESET);
+			/* FIXME need disconnect() for NOTATTACHED device */
+			usb_set_device_state(udev, status
+					? USB_STATE_NOTATTACHED
+					: USB_STATE_DEFAULT);
+			return status;
+		}
+
+		dev_dbg (hub->intfdev,
+			"port %d not enabled, trying reset again...\n",
+			port1);
+		delay = HUB_LONG_RESET_TIME;
+	}
+
+	dev_err (hub->intfdev,
+		"Cannot enable port %i.  Maybe the USB cable is bad?\n",
+		port1);
+
+	return status;
+}
+
+static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
+{
+	struct usb_device *hdev = hub->hdev;
+	int ret;
+
+	if (hdev->children[port1-1] && set_state) {
+		usb_set_device_state(hdev->children[port1-1],
+				USB_STATE_NOTATTACHED);
+	}
+	ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
+	if (ret)
+		dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
+			port1, ret);
+
+	return ret;
+}
+
+/*
+ * Disable a port and mark a logical connnect-change event, so that some
+ * time later khubd will disconnect() any existing usb_device on the port
+ * and will re-enumerate if there actually is a device attached.
+ */
+static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
+{
+	dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
+	hub_port_disable(hub, port1, 1);
+
+	/* FIXME let caller ask to power down the port:
+	 *  - some devices won't enumerate without a VBUS power cycle
+	 *  - SRP saves power that way
+	 *  - usb_suspend_device(dev,PM_SUSPEND_DISK)
+	 * That's easy if this hub can switch power per-port, and
+	 * khubd reactivates the port later (timer, SRP, etc).
+	 * Powerdown must be optional, because of reset/DFU.
+	 */
+
+	set_bit(port1, hub->change_bits);
+ 	kick_khubd(hub);
+}
+
+
+#ifdef	CONFIG_USB_SUSPEND
+
+/*
+ * Selective port suspend reduces power; most suspended devices draw
+ * less than 500 uA.  It's also used in OTG, along with remote wakeup.
+ * All devices below the suspended port are also suspended.
+ *
+ * Devices leave suspend state when the host wakes them up.  Some devices
+ * also support "remote wakeup", where the device can activate the USB
+ * tree above them to deliver data, such as a keypress or packet.  In
+ * some cases, this wakes the USB host.
+ */
+static int hub_port_suspend(struct usb_hub *hub, int port1,
+		struct usb_device *udev)
+{
+	int	status;
+
+	// dev_dbg(hub->intfdev, "suspend port %d\n", port1);
+
+	/* enable remote wakeup when appropriate; this lets the device
+	 * wake up the upstream hub (including maybe the root hub).
+	 *
+	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
+	 * we don't explicitly enable it here.
+	 */
+	if (udev->actconfig
+			// && FIXME (remote wakeup enabled on this bus)
+			// ... currently assuming it's always appropriate
+			&& (udev->actconfig->desc.bmAttributes
+				& USB_CONFIG_ATT_WAKEUP) != 0) {
+		status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
+				USB_DEVICE_REMOTE_WAKEUP, 0,
+				NULL, 0,
+				USB_CTRL_SET_TIMEOUT);
+		if (status)
+			dev_dbg(&udev->dev,
+				"won't remote wakeup, status %d\n",
+				status);
+	}
+
+	/* see 7.1.7.6 */
+	status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
+	if (status) {
+		dev_dbg(hub->intfdev,
+			"can't suspend port %d, status %d\n",
+			port1, status);
+		/* paranoia:  "should not happen" */
+		(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
+				USB_DEVICE_REMOTE_WAKEUP, 0,
+				NULL, 0,
+				USB_CTRL_SET_TIMEOUT);
+	} else {
+		/* device has up to 10 msec to fully suspend */
+		dev_dbg(&udev->dev, "usb suspend\n");
+		usb_set_device_state(udev, USB_STATE_SUSPENDED);
+		msleep(10);
+	}
+	return status;
+}
+
+/*
+ * Devices on USB hub ports have only one "suspend" state, corresponding
+ * to ACPI D2 (PM_SUSPEND_MEM), "may cause the device to lose some context".
+ * State transitions include:
+ *
+ *   - suspend, resume ... when the VBUS power link stays live
+ *   - suspend, disconnect ... VBUS lost
+ *
+ * Once VBUS drop breaks the circuit, the port it's using has to go through
+ * normal re-enumeration procedures, starting with enabling VBUS power.
+ * Other than re-initializing the hub (plug/unplug, except for root hubs),
+ * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
+ * timer, no SRP, no requests through sysfs.
+ */
+static int __usb_suspend_device (struct usb_device *udev, int port1,
+				 pm_message_t state)
+{
+	int	status;
+
+	/* caller owns the udev device lock */
+	if (port1 < 0)
+		return port1;
+
+	if (udev->state == USB_STATE_SUSPENDED
+			|| udev->state == USB_STATE_NOTATTACHED) {
+		return 0;
+	}
+
+	/* suspend interface drivers; if this is a hub, it
+	 * suspends the child devices
+	 */
+	if (udev->actconfig) {
+		int	i;
+
+		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+			struct usb_interface	*intf;
+			struct usb_driver	*driver;
+
+			intf = udev->actconfig->interface[i];
+			if (state <= intf->dev.power.power_state)
+				continue;
+			if (!intf->dev.driver)
+				continue;
+			driver = to_usb_driver(intf->dev.driver);
+
+			if (driver->suspend) {
+				status = driver->suspend(intf, state);
+				if (intf->dev.power.power_state != state
+						|| status)
+					dev_err(&intf->dev,
+						"suspend %d fail, code %d\n",
+						state, status);
+			}
+
+			/* only drivers with suspend() can ever resume();
+			 * and after power loss, even they won't.
+			 * bus_rescan_devices() can rebind drivers later.
+			 *
+			 * FIXME the PM core self-deadlocks when unbinding
+			 * drivers during suspend/resume ... everything grabs
+			 * dpm_sem (not a spinlock, ugh).  we want to unbind,
+			 * since we know every driver's probe/disconnect works
+			 * even for drivers that can't suspend.
+			 */
+			if (!driver->suspend || state > PM_SUSPEND_MEM) {
+#if 1
+				dev_warn(&intf->dev, "resume is unsafe!\n");
+#else
+				down_write(&usb_bus_type.rwsem);
+				device_release_driver(&intf->dev);
+				up_write(&usb_bus_type.rwsem);
+#endif
+			}
+		}
+	}
+
+	/*
+	 * FIXME this needs port power off call paths too, to help force
+	 * USB into the "generic" PM model.  At least for devices on
+	 * ports that aren't using ganged switching (usually root hubs).
+	 *
+	 * NOTE: SRP-capable links should adopt more aggressive poweroff
+	 * policies (when HNP doesn't apply) once we have mechanisms to
+	 * turn power back on!  (Likely not before 2.7...)
+	 */
+	if (state > PM_SUSPEND_MEM) {
+		dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
+	}
+
+	/* "global suspend" of the HC-to-USB interface (root hub), or
+	 * "selective suspend" of just one hub-device link.
+	 */
+	if (!udev->parent) {
+		struct usb_bus	*bus = udev->bus;
+		if (bus && bus->op->hub_suspend) {
+			status = bus->op->hub_suspend (bus);
+			if (status == 0) {
+				dev_dbg(&udev->dev, "usb suspend\n");
+				usb_set_device_state(udev,
+						USB_STATE_SUSPENDED);
+			}
+		} else
+			status = -EOPNOTSUPP;
+	} else
+		status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
+				udev);
+
+	if (status == 0)
+		udev->dev.power.power_state = state;
+	return status;
+}
+
+/**
+ * usb_suspend_device - suspend a usb device
+ * @udev: device that's no longer in active use
+ * @state: PMSG_SUSPEND to suspend
+ * Context: must be able to sleep; device not locked
+ *
+ * Suspends a USB device that isn't in active use, conserving power.
+ * Devices may wake out of a suspend, if anything important happens,
+ * using the remote wakeup mechanism.  They may also be taken out of
+ * suspend by the host, using usb_resume_device().  It's also routine
+ * to disconnect devices while they are suspended.
+ *
+ * Suspending OTG devices may trigger HNP, if that's been enabled
+ * between a pair of dual-role devices.  That will change roles, such
+ * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int usb_suspend_device(struct usb_device *udev, pm_message_t state)
+{
+	int	port1, status;
+
+	port1 = locktree(udev);
+	if (port1 < 0)
+		return port1;
+
+	status = __usb_suspend_device(udev, port1, state);
+	usb_unlock_device(udev);
+	return status;
+}
+
+/*
+ * hardware resume signaling is finished, either because of selective
+ * resume (by host) or remote wakeup (by device) ... now see what changed
+ * in the tree that's rooted at this device.
+ */
+static int finish_port_resume(struct usb_device *udev)
+{
+	int	status;
+	u16	devstatus;
+
+	/* caller owns the udev device lock */
+	dev_dbg(&udev->dev, "usb resume\n");
+
+	/* usb ch9 identifies four variants of SUSPENDED, based on what
+	 * state the device resumes to.  Linux currently won't see the
+	 * first two on the host side; they'd be inside hub_port_init()
+	 * during many timeouts, but khubd can't suspend until later.
+	 */
+	usb_set_device_state(udev, udev->actconfig
+			? USB_STATE_CONFIGURED
+			: USB_STATE_ADDRESS);
+	udev->dev.power.power_state = PMSG_ON;
+
+ 	/* 10.5.4.5 says be sure devices in the tree are still there.
+ 	 * For now let's assume the device didn't go crazy on resume,
+	 * and device drivers will know about any resume quirks.
+	 */
+	status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
+	if (status < 0)
+		dev_dbg(&udev->dev,
+			"gone after usb resume? status %d\n",
+			status);
+	else if (udev->actconfig) {
+		unsigned	i;
+
+		le16_to_cpus(&devstatus);
+		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
+			status = usb_control_msg(udev,
+					usb_sndctrlpipe(udev, 0),
+					USB_REQ_CLEAR_FEATURE,
+						USB_RECIP_DEVICE,
+					USB_DEVICE_REMOTE_WAKEUP, 0,
+					NULL, 0,
+					USB_CTRL_SET_TIMEOUT);
+			if (status) {
+				dev_dbg(&udev->dev, "disable remote "
+					"wakeup, status %d\n", status);
+				status = 0;
+			}
+		}
+
+		/* resume interface drivers; if this is a hub, it
+		 * resumes the child devices
+		 */
+		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+			struct usb_interface	*intf;
+			struct usb_driver	*driver;
+
+			intf = udev->actconfig->interface[i];
+			if (intf->dev.power.power_state == PM_SUSPEND_ON)
+				continue;
+			if (!intf->dev.driver) {
+				/* FIXME maybe force to alt 0 */
+				continue;
+			}
+			driver = to_usb_driver(intf->dev.driver);
+
+			/* bus_rescan_devices() may rebind drivers */
+			if (!driver->resume)
+				continue;
+
+			/* can we do better than just logging errors? */
+			status = driver->resume(intf);
+			if (intf->dev.power.power_state != PM_SUSPEND_ON
+					|| status)
+				dev_dbg(&intf->dev,
+					"resume fail, state %d code %d\n",
+					intf->dev.power.power_state, status);
+		}
+		status = 0;
+
+	} else if (udev->devnum <= 0) {
+		dev_dbg(&udev->dev, "bogus resume!\n");
+		status = -EINVAL;
+	}
+	return status;
+}
+
+static int
+hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
+{
+	int	status;
+
+	// dev_dbg(hub->intfdev, "resume port %d\n", port1);
+
+	/* see 7.1.7.7; affects power usage, but not budgeting */
+	status = clear_port_feature(hub->hdev,
+			port1, USB_PORT_FEAT_SUSPEND);
+	if (status) {
+		dev_dbg(hub->intfdev,
+			"can't resume port %d, status %d\n",
+			port1, status);
+	} else {
+		u16		devstatus;
+		u16		portchange;
+
+		/* drive resume for at least 20 msec */
+		if (udev)
+			dev_dbg(&udev->dev, "RESUME\n");
+		msleep(25);
+
+#define LIVE_FLAGS	( USB_PORT_STAT_POWER \
+			| USB_PORT_STAT_ENABLE \
+			| USB_PORT_STAT_CONNECTION)
+
+		/* Virtual root hubs can trigger on GET_PORT_STATUS to
+		 * stop resume signaling.  Then finish the resume
+		 * sequence.
+		 */
+		devstatus = portchange = 0;
+		status = hub_port_status(hub, port1,
+				&devstatus, &portchange);
+		if (status < 0
+				|| (devstatus & LIVE_FLAGS) != LIVE_FLAGS
+				|| (devstatus & USB_PORT_STAT_SUSPEND) != 0
+				) {
+			dev_dbg(hub->intfdev,
+				"port %d status %04x.%04x after resume, %d\n",
+				port1, portchange, devstatus, status);
+		} else {
+			/* TRSMRCY = 10 msec */
+			msleep(10);
+			if (udev)
+				status = finish_port_resume(udev);
+		}
+	}
+	if (status < 0)
+		hub_port_logical_disconnect(hub, port1);
+
+	return status;
+}
+
+static int hub_resume (struct usb_interface *intf);
+
+/**
+ * usb_resume_device - re-activate a suspended usb device
+ * @udev: device to re-activate
+ * Context: must be able to sleep; device not locked
+ *
+ * This will re-activate the suspended device, increasing power usage
+ * while letting drivers communicate again with its endpoints.
+ * USB resume explicitly guarantees that the power session between
+ * the host and the device is the same as it was when the device
+ * suspended.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int usb_resume_device(struct usb_device *udev)
+{
+	int	port1, status;
+
+	port1 = locktree(udev);
+	if (port1 < 0)
+		return port1;
+
+	/* "global resume" of the HC-to-USB interface (root hub), or
+	 * selective resume of one hub-to-device port
+	 */
+	if (!udev->parent) {
+		struct usb_bus	*bus = udev->bus;
+		if (bus && bus->op->hub_resume) {
+			status = bus->op->hub_resume (bus);
+		} else
+			status = -EOPNOTSUPP;
+		if (status == 0) {
+			dev_dbg(&udev->dev, "usb resume\n");
+			/* TRSMRCY = 10 msec */
+			msleep(10);
+			usb_set_device_state (udev, USB_STATE_CONFIGURED);
+			udev->dev.power.power_state = PMSG_ON;
+			status = hub_resume (udev
+					->actconfig->interface[0]);
+		}
+	} else if (udev->state == USB_STATE_SUSPENDED) {
+		// NOTE this fails if parent is also suspended...
+		status = hub_port_resume(hdev_to_hub(udev->parent),
+				port1, udev);
+	} else {
+		status = 0;
+	}
+	if (status < 0) {
+		dev_dbg(&udev->dev, "can't resume, status %d\n",
+			status);
+	}
+
+	usb_unlock_device(udev);
+
+	/* rebind drivers that had no suspend() */
+	if (status == 0) {
+		usb_lock_all_devices();
+		bus_rescan_devices(&usb_bus_type);
+		usb_unlock_all_devices();
+	}
+	return status;
+}
+
+static int remote_wakeup(struct usb_device *udev)
+{
+	int	status = 0;
+
+	/* don't repeat RESUME sequence if this device
+	 * was already woken up by some other task
+	 */
+	down(&udev->serialize);
+	if (udev->state == USB_STATE_SUSPENDED) {
+		dev_dbg(&udev->dev, "RESUME (wakeup)\n");
+		/* TRSMRCY = 10 msec */
+		msleep(10);
+		status = finish_port_resume(udev);
+	}
+	up(&udev->serialize);
+	return status;
+}
+
+static int hub_suspend(struct usb_interface *intf, pm_message_t state)
+{
+	struct usb_hub		*hub = usb_get_intfdata (intf);
+	struct usb_device	*hdev = hub->hdev;
+	unsigned		port1;
+	int			status;
+
+	/* stop khubd and related activity */
+	hub_quiesce(hub);
+
+	/* then suspend every port */
+	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
+		struct usb_device	*udev;
+
+		udev = hdev->children [port1-1];
+		if (!udev)
+			continue;
+		down(&udev->serialize);
+		status = __usb_suspend_device(udev, port1, state);
+		up(&udev->serialize);
+		if (status < 0)
+			dev_dbg(&intf->dev, "suspend port %d --> %d\n",
+				port1, status);
+	}
+
+	intf->dev.power.power_state = state;
+	return 0;
+}
+
+static int hub_resume(struct usb_interface *intf)
+{
+	struct usb_device	*hdev = interface_to_usbdev(intf);
+	struct usb_hub		*hub = usb_get_intfdata (intf);
+	unsigned		port1;
+	int			status;
+
+	if (intf->dev.power.power_state == PM_SUSPEND_ON)
+		return 0;
+
+	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
+		struct usb_device	*udev;
+		u16			portstat, portchange;
+
+		udev = hdev->children [port1-1];
+		status = hub_port_status(hub, port1, &portstat, &portchange);
+		if (status == 0) {
+			if (portchange & USB_PORT_STAT_C_SUSPEND) {
+				clear_port_feature(hdev, port1,
+					USB_PORT_FEAT_C_SUSPEND);
+				portchange &= ~USB_PORT_STAT_C_SUSPEND;
+			}
+
+			/* let khubd handle disconnects etc */
+			if (portchange)
+				continue;
+		}
+
+		if (!udev || status < 0)
+			continue;
+		down (&udev->serialize);
+		if (portstat & USB_PORT_STAT_SUSPEND)
+			status = hub_port_resume(hub, port1, udev);
+		else {
+			status = finish_port_resume(udev);
+			if (status < 0) {
+				dev_dbg(&intf->dev, "resume port %d --> %d\n",
+					port1, status);
+				hub_port_logical_disconnect(hub, port1);
+			}
+		}
+		up(&udev->serialize);
+	}
+	intf->dev.power.power_state = PMSG_ON;
+
+	hub->resume_root_hub = 0;
+	hub_activate(hub);
+	return 0;
+}
+
+void usb_resume_root_hub(struct usb_device *hdev)
+{
+	struct usb_hub *hub = hdev_to_hub(hdev);
+
+	hub->resume_root_hub = 1;
+	kick_khubd(hub);
+}
+
+#else	/* !CONFIG_USB_SUSPEND */
+
+int usb_suspend_device(struct usb_device *udev, pm_message_t state)
+{
+	return 0;
+}
+
+int usb_resume_device(struct usb_device *udev)
+{
+	return 0;
+}
+
+#define	hub_suspend		NULL
+#define	hub_resume		NULL
+#define	remote_wakeup(x)	0
+
+#endif	/* CONFIG_USB_SUSPEND */
+
+EXPORT_SYMBOL(usb_suspend_device);
+EXPORT_SYMBOL(usb_resume_device);
+
+
+
+/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
+ *
+ * Between connect detection and reset signaling there must be a delay
+ * of 100ms at least for debounce and power-settling.  The corresponding
+ * timer shall restart whenever the downstream port detects a disconnect.
+ * 
+ * Apparently there are some bluetooth and irda-dongles and a number of
+ * low-speed devices for which this debounce period may last over a second.
+ * Not covered by the spec - but easy to deal with.
+ *
+ * This implementation uses a 1500ms total debounce timeout; if the
+ * connection isn't stable by then it returns -ETIMEDOUT.  It checks
+ * every 25ms for transient disconnects.  When the port status has been
+ * unchanged for 100ms it returns the port status.
+ */
+
+#define HUB_DEBOUNCE_TIMEOUT	1500
+#define HUB_DEBOUNCE_STEP	  25
+#define HUB_DEBOUNCE_STABLE	 100
+
+static int hub_port_debounce(struct usb_hub *hub, int port1)
+{
+	int ret;
+	int total_time, stable_time = 0;
+	u16 portchange, portstatus;
+	unsigned connection = 0xffff;
+
+	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
+		ret = hub_port_status(hub, port1, &portstatus, &portchange);
+		if (ret < 0)
+			return ret;
+
+		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
+		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
+			stable_time += HUB_DEBOUNCE_STEP;
+			if (stable_time >= HUB_DEBOUNCE_STABLE)
+				break;
+		} else {
+			stable_time = 0;
+			connection = portstatus & USB_PORT_STAT_CONNECTION;
+		}
+
+		if (portchange & USB_PORT_STAT_C_CONNECTION) {
+			clear_port_feature(hub->hdev, port1,
+					USB_PORT_FEAT_C_CONNECTION);
+		}
+
+		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
+			break;
+		msleep(HUB_DEBOUNCE_STEP);
+	}
+
+	dev_dbg (hub->intfdev,
+		"debounce: port %d: total %dms stable %dms status 0x%x\n",
+		port1, total_time, stable_time, portstatus);
+
+	if (stable_time < HUB_DEBOUNCE_STABLE)
+		return -ETIMEDOUT;
+	return portstatus;
+}
+
+static void ep0_reinit(struct usb_device *udev)
+{
+	usb_disable_endpoint(udev, 0 + USB_DIR_IN);
+	usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
+	udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
+}
+
+#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
+#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
+
+static int hub_set_address(struct usb_device *udev)
+{
+	int retval;
+
+	if (udev->devnum == 0)
+		return -EINVAL;
+	if (udev->state == USB_STATE_ADDRESS)
+		return 0;
+	if (udev->state != USB_STATE_DEFAULT)
+		return -EINVAL;
+	retval = usb_control_msg(udev, usb_sndaddr0pipe(),
+		USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
+		NULL, 0, USB_CTRL_SET_TIMEOUT);
+	if (retval == 0) {
+		usb_set_device_state(udev, USB_STATE_ADDRESS);
+		ep0_reinit(udev);
+	}
+	return retval;
+}
+
+/* Reset device, (re)assign address, get device descriptor.
+ * Device connection must be stable, no more debouncing needed.
+ * Returns device in USB_STATE_ADDRESS, except on error.
+ *
+ * If this is called for an already-existing device (as part of
+ * usb_reset_device), the caller must own the device lock.  For a
+ * newly detected device that is not accessible through any global
+ * pointers, it's not necessary to lock the device.
+ */
+static int
+hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
+		int retry_counter)
+{
+	static DECLARE_MUTEX(usb_address0_sem);
+
+	struct usb_device	*hdev = hub->hdev;
+	int			i, j, retval;
+	unsigned		delay = HUB_SHORT_RESET_TIME;
+	enum usb_device_speed	oldspeed = udev->speed;
+
+	/* root hub ports have a slightly longer reset period
+	 * (from USB 2.0 spec, section 7.1.7.5)
+	 */
+	if (!hdev->parent) {
+		delay = HUB_ROOT_RESET_TIME;
+		if (port1 == hdev->bus->otg_port)
+			hdev->bus->b_hnp_enable = 0;
+	}
+
+	/* Some low speed devices have problems with the quick delay, so */
+	/*  be a bit pessimistic with those devices. RHbug #23670 */
+	if (oldspeed == USB_SPEED_LOW)
+		delay = HUB_LONG_RESET_TIME;
+
+	down(&usb_address0_sem);
+
+	/* Reset the device; full speed may morph to high speed */
+	retval = hub_port_reset(hub, port1, udev, delay);
+	if (retval < 0)		/* error or disconnect */
+		goto fail;
+				/* success, speed is known */
+	retval = -ENODEV;
+
+	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
+		dev_dbg(&udev->dev, "device reset changed speed!\n");
+		goto fail;
+	}
+	oldspeed = udev->speed;
+  
+	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
+	 * it's fixed size except for full speed devices.
+	 */
+	switch (udev->speed) {
+	case USB_SPEED_HIGH:		/* fixed at 64 */
+		udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
+		break;
+	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
+		/* to determine the ep0 maxpacket size, try to read
+		 * the device descriptor to get bMaxPacketSize0 and
+		 * then correct our initial guess.
+		 */
+		udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
+		break;
+	case USB_SPEED_LOW:		/* fixed at 8 */
+		udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
+		break;
+	default:
+		goto fail;
+	}
+ 
+	dev_info (&udev->dev,
+			"%s %s speed USB device using %s and address %d\n",
+			(udev->config) ? "reset" : "new",
+			({ char *speed; switch (udev->speed) {
+			case USB_SPEED_LOW:	speed = "low";	break;
+			case USB_SPEED_FULL:	speed = "full";	break;
+			case USB_SPEED_HIGH:	speed = "high";	break;
+			default: 		speed = "?";	break;
+			}; speed;}),
+			udev->bus->controller->driver->name,
+			udev->devnum);
+
+	/* Set up TT records, if needed  */
+	if (hdev->tt) {
+		udev->tt = hdev->tt;
+		udev->ttport = hdev->ttport;
+	} else if (udev->speed != USB_SPEED_HIGH
+			&& hdev->speed == USB_SPEED_HIGH) {
+		udev->tt = &hub->tt;
+		udev->ttport = port1;
+	}
+ 
+	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
+	 * Because device hardware and firmware is sometimes buggy in
+	 * this area, and this is how Linux has done it for ages.
+	 * Change it cautiously.
+	 *
+	 * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
+	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
+	 * so it may help with some non-standards-compliant devices.
+	 * Otherwise we start with SET_ADDRESS and then try to read the
+	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
+	 * value.
+	 */
+	for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
+		if (USE_NEW_SCHEME(retry_counter)) {
+			struct usb_device_descriptor *buf;
+			int r = 0;
+
+#define GET_DESCRIPTOR_BUFSIZE	64
+			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
+			if (!buf) {
+				retval = -ENOMEM;
+				continue;
+			}
+
+			/* Use a short timeout the first time through,
+			 * so that recalcitrant full-speed devices with
+			 * 8- or 16-byte ep0-maxpackets won't slow things
+			 * down tremendously by NAKing the unexpectedly
+			 * early status stage.  Also, retry on all errors;
+			 * some devices are flakey.
+			 */
+			for (j = 0; j < 3; ++j) {
+				buf->bMaxPacketSize0 = 0;
+				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
+					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
+					USB_DT_DEVICE << 8, 0,
+					buf, GET_DESCRIPTOR_BUFSIZE,
+					(i ? USB_CTRL_GET_TIMEOUT : 1000));
+				switch (buf->bMaxPacketSize0) {
+				case 8: case 16: case 32: case 64:
+					if (buf->bDescriptorType ==
+							USB_DT_DEVICE) {
+						r = 0;
+						break;
+					}
+					/* FALL THROUGH */
+				default:
+					if (r == 0)
+						r = -EPROTO;
+					break;
+				}
+				if (r == 0)
+					break;
+			}
+			udev->descriptor.bMaxPacketSize0 =
+					buf->bMaxPacketSize0;
+			kfree(buf);
+
+			retval = hub_port_reset(hub, port1, udev, delay);
+			if (retval < 0)		/* error or disconnect */
+				goto fail;
+			if (oldspeed != udev->speed) {
+				dev_dbg(&udev->dev,
+					"device reset changed speed!\n");
+				retval = -ENODEV;
+				goto fail;
+			}
+			if (r) {
+				dev_err(&udev->dev, "device descriptor "
+						"read/%s, error %d\n",
+						"64", r);
+				retval = -EMSGSIZE;
+				continue;
+			}
+#undef GET_DESCRIPTOR_BUFSIZE
+		}
+
+		for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
+			retval = hub_set_address(udev);
+			if (retval >= 0)
+				break;
+			msleep(200);
+		}
+		if (retval < 0) {
+			dev_err(&udev->dev,
+				"device not accepting address %d, error %d\n",
+				udev->devnum, retval);
+			goto fail;
+		}
+ 
+		/* cope with hardware quirkiness:
+		 *  - let SET_ADDRESS settle, some device hardware wants it
+		 *  - read ep0 maxpacket even for high and low speed,
+  		 */
+		msleep(10);
+		if (USE_NEW_SCHEME(retry_counter))
+			break;
+
+		retval = usb_get_device_descriptor(udev, 8);
+		if (retval < 8) {
+			dev_err(&udev->dev, "device descriptor "
+					"read/%s, error %d\n",
+					"8", retval);
+			if (retval >= 0)
+				retval = -EMSGSIZE;
+		} else {
+			retval = 0;
+			break;
+		}
+	}
+	if (retval)
+		goto fail;
+
+	i = udev->descriptor.bMaxPacketSize0;
+	if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
+		if (udev->speed != USB_SPEED_FULL ||
+				!(i == 8 || i == 16 || i == 32 || i == 64)) {
+			dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
+			retval = -EMSGSIZE;
+			goto fail;
+		}
+		dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
+		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
+		ep0_reinit(udev);
+	}
+  
+	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
+	if (retval < (signed)sizeof(udev->descriptor)) {
+		dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
+			"all", retval);
+		if (retval >= 0)
+			retval = -ENOMSG;
+		goto fail;
+	}
+
+	retval = 0;
+
+fail:
+	if (retval)
+		hub_port_disable(hub, port1, 0);
+	up(&usb_address0_sem);
+	return retval;
+}
+
+static void
+check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
+{
+	struct usb_qualifier_descriptor	*qual;
+	int				status;
+
+	qual = kmalloc (sizeof *qual, SLAB_KERNEL);
+	if (qual == NULL)
+		return;
+
+	status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
+			qual, sizeof *qual);
+	if (status == sizeof *qual) {
+		dev_info(&udev->dev, "not running at top speed; "
+			"connect to a high speed hub\n");
+		/* hub LEDs are probably harder to miss than syslog */
+		if (hub->has_indicators) {
+			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
+			schedule_work (&hub->leds);
+		}
+	}
+	kfree (qual);
+}
+
+static unsigned
+hub_power_remaining (struct usb_hub *hub)
+{
+	struct usb_device *hdev = hub->hdev;
+	int remaining;
+	unsigned i;
+
+	remaining = hub->power_budget;
+	if (!remaining)		/* self-powered */
+		return 0;
+
+	for (i = 0; i < hdev->maxchild; i++) {
+		struct usb_device	*udev = hdev->children[i];
+		int			delta, ceiling;
+
+		if (!udev)
+			continue;
+
+		/* 100mA per-port ceiling, or 8mA for OTG ports */
+		if (i != (udev->bus->otg_port - 1) || hdev->parent)
+			ceiling = 50;
+		else
+			ceiling = 4;
+
+		if (udev->actconfig)
+			delta = udev->actconfig->desc.bMaxPower;
+		else
+			delta = ceiling;
+		// dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
+		if (delta > ceiling)
+			dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
+				2 * (delta - ceiling), 2 * ceiling);
+		remaining -= delta;
+	}
+	if (remaining < 0) {
+		dev_warn(hub->intfdev,
+			"%dmA over power budget!\n",
+			-2 * remaining);
+		remaining = 0;
+	}
+	return remaining;
+}
+
+/* Handle physical or logical connection change events.
+ * This routine is called when:
+ * 	a port connection-change occurs;
+ *	a port enable-change occurs (often caused by EMI);
+ *	usb_reset_device() encounters changed descriptors (as from
+ *		a firmware download)
+ * caller already locked the hub
+ */
+static void hub_port_connect_change(struct usb_hub *hub, int port1,
+					u16 portstatus, u16 portchange)
+{
+	struct usb_device *hdev = hub->hdev;
+	struct device *hub_dev = hub->intfdev;
+	int status, i;
+ 
+	dev_dbg (hub_dev,
+		"port %d, status %04x, change %04x, %s\n",
+		port1, portstatus, portchange, portspeed (portstatus));
+
+	if (hub->has_indicators) {
+		set_port_led(hub, port1, HUB_LED_AUTO);
+		hub->indicator[port1-1] = INDICATOR_AUTO;
+	}
+ 
+	/* Disconnect any existing devices under this port */
+	if (hdev->children[port1-1])
+		usb_disconnect(&hdev->children[port1-1]);
+	clear_bit(port1, hub->change_bits);
+
+#ifdef	CONFIG_USB_OTG
+	/* during HNP, don't repeat the debounce */
+	if (hdev->bus->is_b_host)
+		portchange &= ~USB_PORT_STAT_C_CONNECTION;
+#endif
+
+	if (portchange & USB_PORT_STAT_C_CONNECTION) {
+		status = hub_port_debounce(hub, port1);
+		if (status < 0) {
+			dev_err (hub_dev,
+				"connect-debounce failed, port %d disabled\n",
+				port1);
+			goto done;
+		}
+		portstatus = status;
+	}
+
+	/* Return now if nothing is connected */
+	if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
+
+		/* maybe switch power back on (e.g. root hub was reset) */
+		if ((hub->descriptor->wHubCharacteristics
+					& HUB_CHAR_LPSM) < 2
+				&& !(portstatus & (1 << USB_PORT_FEAT_POWER)))
+			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
+ 
+		if (portstatus & USB_PORT_STAT_ENABLE)
+  			goto done;
+		return;
+	}
+
+#ifdef  CONFIG_USB_SUSPEND
+	/* If something is connected, but the port is suspended, wake it up. */
+	if (portstatus & USB_PORT_STAT_SUSPEND) {
+		status = hub_port_resume(hub, port1, NULL);
+		if (status < 0) {
+			dev_dbg(hub_dev,
+				"can't clear suspend on port %d; %d\n",
+				port1, status);
+			goto done;
+		}
+	}
+#endif
+
+	for (i = 0; i < SET_CONFIG_TRIES; i++) {
+		struct usb_device *udev;
+
+		/* reallocate for each attempt, since references
+		 * to the previous one can escape in various ways
+		 */
+		udev = usb_alloc_dev(hdev, hdev->bus, port1);
+		if (!udev) {
+			dev_err (hub_dev,
+				"couldn't allocate port %d usb_device\n",
+				port1);
+			goto done;
+		}
+
+		usb_set_device_state(udev, USB_STATE_POWERED);
+		udev->speed = USB_SPEED_UNKNOWN;
+ 
+		/* set the address */
+		choose_address(udev);
+		if (udev->devnum <= 0) {
+			status = -ENOTCONN;	/* Don't retry */
+			goto loop;
+		}
+
+		/* reset and get descriptor */
+		status = hub_port_init(hub, udev, port1, i);
+		if (status < 0)
+			goto loop;
+
+		/* consecutive bus-powered hubs aren't reliable; they can
+		 * violate the voltage drop budget.  if the new child has
+		 * a "powered" LED, users should notice we didn't enable it
+		 * (without reading syslog), even without per-port LEDs
+		 * on the parent.
+		 */
+		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
+				&& hub->power_budget) {
+			u16	devstat;
+
+			status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
+					&devstat);
+			if (status < 0) {
+				dev_dbg(&udev->dev, "get status %d ?\n", status);
+				goto loop_disable;
+			}
+			cpu_to_le16s(&devstat);
+			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
+				dev_err(&udev->dev,
+					"can't connect bus-powered hub "
+					"to this port\n");
+				if (hub->has_indicators) {
+					hub->indicator[port1-1] =
+						INDICATOR_AMBER_BLINK;
+					schedule_work (&hub->leds);
+				}
+				status = -ENOTCONN;	/* Don't retry */
+				goto loop_disable;
+			}
+		}
+ 
+		/* check for devices running slower than they could */
+		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
+				&& udev->speed == USB_SPEED_FULL
+				&& highspeed_hubs != 0)
+			check_highspeed (hub, udev, port1);
+
+		/* Store the parent's children[] pointer.  At this point
+		 * udev becomes globally accessible, although presumably
+		 * no one will look at it until hdev is unlocked.
+		 */
+		down (&udev->serialize);
+		status = 0;
+
+		/* We mustn't add new devices if the parent hub has
+		 * been disconnected; we would race with the
+		 * recursively_mark_NOTATTACHED() routine.
+		 */
+		spin_lock_irq(&device_state_lock);
+		if (hdev->state == USB_STATE_NOTATTACHED)
+			status = -ENOTCONN;
+		else
+			hdev->children[port1-1] = udev;
+		spin_unlock_irq(&device_state_lock);
+
+		/* Run it through the hoops (find a driver, etc) */
+		if (!status) {
+			status = usb_new_device(udev);
+			if (status) {
+				spin_lock_irq(&device_state_lock);
+				hdev->children[port1-1] = NULL;
+				spin_unlock_irq(&device_state_lock);
+			}
+		}
+
+		up (&udev->serialize);
+		if (status)
+			goto loop_disable;
+
+		status = hub_power_remaining(hub);
+		if (status)
+			dev_dbg(hub_dev,
+				"%dmA power budget left\n",
+				2 * status);
+
+		return;
+
+loop_disable:
+		hub_port_disable(hub, port1, 1);
+loop:
+		ep0_reinit(udev);
+		release_address(udev);
+		usb_put_dev(udev);
+		if (status == -ENOTCONN)
+			break;
+	}
+ 
+done:
+	hub_port_disable(hub, port1, 1);
+}
+
+static void hub_events(void)
+{
+	struct list_head *tmp;
+	struct usb_device *hdev;
+	struct usb_interface *intf;
+	struct usb_hub *hub;
+	struct device *hub_dev;
+	u16 hubstatus;
+	u16 hubchange;
+	u16 portstatus;
+	u16 portchange;
+	int i, ret;
+	int connect_change;
+
+	/*
+	 *  We restart the list every time to avoid a deadlock with
+	 * deleting hubs downstream from this one. This should be
+	 * safe since we delete the hub from the event list.
+	 * Not the most efficient, but avoids deadlocks.
+	 */
+	while (1) {
+
+		/* Grab the first entry at the beginning of the list */
+		spin_lock_irq(&hub_event_lock);
+		if (list_empty(&hub_event_list)) {
+			spin_unlock_irq(&hub_event_lock);
+			break;
+		}
+
+		tmp = hub_event_list.next;
+		list_del_init(tmp);
+
+		hub = list_entry(tmp, struct usb_hub, event_list);
+		hdev = hub->hdev;
+		intf = to_usb_interface(hub->intfdev);
+		hub_dev = &intf->dev;
+
+		dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
+				hdev->state, hub->descriptor
+					? hub->descriptor->bNbrPorts
+					: 0,
+				/* NOTE: expects max 15 ports... */
+				(u16) hub->change_bits[0],
+				(u16) hub->event_bits[0]);
+
+		usb_get_intf(intf);
+		i = hub->resume_root_hub;
+		spin_unlock_irq(&hub_event_lock);
+
+		/* Is this is a root hub wanting to be resumed? */
+		if (i)
+			usb_resume_device(hdev);
+
+		/* Lock the device, then check to see if we were
+		 * disconnected while waiting for the lock to succeed. */
+		if (locktree(hdev) < 0) {
+			usb_put_intf(intf);
+			continue;
+		}
+		if (hub != usb_get_intfdata(intf))
+			goto loop;
+
+		/* If the hub has died, clean up after it */
+		if (hdev->state == USB_STATE_NOTATTACHED) {
+			hub_pre_reset(hub);
+			goto loop;
+		}
+
+		/* If this is an inactive or suspended hub, do nothing */
+		if (hub->quiescing)
+			goto loop;
+
+		if (hub->error) {
+			dev_dbg (hub_dev, "resetting for error %d\n",
+				hub->error);
+
+			ret = usb_reset_device(hdev);
+			if (ret) {
+				dev_dbg (hub_dev,
+					"error resetting hub: %d\n", ret);
+				goto loop;
+			}
+
+			hub->nerrors = 0;
+			hub->error = 0;
+		}
+
+		/* deal with port status changes */
+		for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
+			if (test_bit(i, hub->busy_bits))
+				continue;
+			connect_change = test_bit(i, hub->change_bits);
+			if (!test_and_clear_bit(i, hub->event_bits) &&
+					!connect_change && !hub->activating)
+				continue;
+
+			ret = hub_port_status(hub, i,
+					&portstatus, &portchange);
+			if (ret < 0)
+				continue;
+
+			if (hub->activating && !hdev->children[i-1] &&
+					(portstatus &
+						USB_PORT_STAT_CONNECTION))
+				connect_change = 1;
+
+			if (portchange & USB_PORT_STAT_C_CONNECTION) {
+				clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_CONNECTION);
+				connect_change = 1;
+			}
+
+			if (portchange & USB_PORT_STAT_C_ENABLE) {
+				if (!connect_change)
+					dev_dbg (hub_dev,
+						"port %d enable change, "
+						"status %08x\n",
+						i, portstatus);
+				clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_ENABLE);
+
+				/*
+				 * EM interference sometimes causes badly
+				 * shielded USB devices to be shutdown by
+				 * the hub, this hack enables them again.
+				 * Works at least with mouse driver. 
+				 */
+				if (!(portstatus & USB_PORT_STAT_ENABLE)
+				    && !connect_change
+				    && hdev->children[i-1]) {
+					dev_err (hub_dev,
+					    "port %i "
+					    "disabled by hub (EMI?), "
+					    "re-enabling...\n",
+						i);
+					connect_change = 1;
+				}
+			}
+
+			if (portchange & USB_PORT_STAT_C_SUSPEND) {
+				clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_SUSPEND);
+				if (hdev->children[i-1]) {
+					ret = remote_wakeup(hdev->
+							children[i-1]);
+					if (ret < 0)
+						connect_change = 1;
+				} else {
+					ret = -ENODEV;
+					hub_port_disable(hub, i, 1);
+				}
+				dev_dbg (hub_dev,
+					"resume on port %d, status %d\n",
+					i, ret);
+			}
+			
+			if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
+				dev_err (hub_dev,
+					"over-current change on port %d\n",
+					i);
+				clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_OVER_CURRENT);
+				hub_power_on(hub);
+			}
+
+			if (portchange & USB_PORT_STAT_C_RESET) {
+				dev_dbg (hub_dev,
+					"reset change on port %d\n",
+					i);
+				clear_port_feature(hdev, i,
+					USB_PORT_FEAT_C_RESET);
+			}
+
+			if (connect_change)
+				hub_port_connect_change(hub, i,
+						portstatus, portchange);
+		} /* end for i */
+
+		/* deal with hub status changes */
+		if (test_and_clear_bit(0, hub->event_bits) == 0)
+			;	/* do nothing */
+		else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
+			dev_err (hub_dev, "get_hub_status failed\n");
+		else {
+			if (hubchange & HUB_CHANGE_LOCAL_POWER) {
+				dev_dbg (hub_dev, "power change\n");
+				clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
+			}
+			if (hubchange & HUB_CHANGE_OVERCURRENT) {
+				dev_dbg (hub_dev, "overcurrent change\n");
+				msleep(500);	/* Cool down */
+				clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
+                        	hub_power_on(hub);
+			}
+		}
+
+		hub->activating = 0;
+
+loop:
+		usb_unlock_device(hdev);
+		usb_put_intf(intf);
+
+        } /* end while (1) */
+}
+
+static int hub_thread(void *__unused)
+{
+	/*
+	 * This thread doesn't need any user-level access,
+	 * so get rid of all our resources
+	 */
+
+	daemonize("khubd");
+	allow_signal(SIGKILL);
+
+	/* Send me a signal to get me die (for debugging) */
+	do {
+		hub_events();
+		wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list)); 
+		try_to_freeze(PF_FREEZE);
+	} while (!signal_pending(current));
+
+	pr_debug ("%s: khubd exiting\n", usbcore_name);
+	complete_and_exit(&khubd_exited, 0);
+}
+
+static struct usb_device_id hub_id_table [] = {
+    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
+      .bDeviceClass = USB_CLASS_HUB},
+    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
+      .bInterfaceClass = USB_CLASS_HUB},
+    { }						/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE (usb, hub_id_table);
+
+static struct usb_driver hub_driver = {
+	.owner =	THIS_MODULE,
+	.name =		"hub",
+	.probe =	hub_probe,
+	.disconnect =	hub_disconnect,
+	.suspend =	hub_suspend,
+	.resume =	hub_resume,
+	.ioctl =	hub_ioctl,
+	.id_table =	hub_id_table,
+};
+
+int usb_hub_init(void)
+{
+	pid_t pid;
+
+	if (usb_register(&hub_driver) < 0) {
+		printk(KERN_ERR "%s: can't register hub driver\n",
+			usbcore_name);
+		return -1;
+	}
+
+	pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
+	if (pid >= 0) {
+		khubd_pid = pid;
+
+		return 0;
+	}
+
+	/* Fall through if kernel_thread failed */
+	usb_deregister(&hub_driver);
+	printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
+
+	return -1;
+}
+
+void usb_hub_cleanup(void)
+{
+	int ret;
+
+	/* Kill the thread */
+	ret = kill_proc(khubd_pid, SIGKILL, 1);
+
+	wait_for_completion(&khubd_exited);
+
+	/*
+	 * Hub resources are freed for us by usb_deregister. It calls
+	 * usb_driver_purge on every device which in turn calls that
+	 * devices disconnect function if it is using this driver.
+	 * The hub_disconnect function takes care of releasing the
+	 * individual hub resources. -greg
+	 */
+	usb_deregister(&hub_driver);
+} /* usb_hub_cleanup() */
+
+
+static int config_descriptors_changed(struct usb_device *udev)
+{
+	unsigned			index;
+	unsigned			len = 0;
+	struct usb_config_descriptor	*buf;
+
+	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
+		if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
+			len = le16_to_cpu(udev->config[index].desc.wTotalLength);
+	}
+	buf = kmalloc (len, SLAB_KERNEL);
+	if (buf == NULL) {
+		dev_err(&udev->dev, "no mem to re-read configs after reset\n");
+		/* assume the worst */
+		return 1;
+	}
+	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
+		int length;
+		int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
+
+		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
+				old_length);
+		if (length < old_length) {
+			dev_dbg(&udev->dev, "config index %d, error %d\n",
+					index, length);
+			break;
+		}
+		if (memcmp (buf, udev->rawdescriptors[index], old_length)
+				!= 0) {
+			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
+				index, buf->bConfigurationValue);
+			break;
+		}
+	}
+	kfree(buf);
+	return index != udev->descriptor.bNumConfigurations;
+}
+
+/**
+ * usb_reset_device - perform a USB port reset to reinitialize a device
+ * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
+ *
+ * WARNING - don't reset any device unless drivers for all of its
+ * interfaces are expecting that reset!  Maybe some driver->reset()
+ * method should eventually help ensure sufficient cooperation.
+ *
+ * Do a port reset, reassign the device's address, and establish its
+ * former operating configuration.  If the reset fails, or the device's
+ * descriptors change from their values before the reset, or the original
+ * configuration and altsettings cannot be restored, a flag will be set
+ * telling khubd to pretend the device has been disconnected and then
+ * re-connected.  All drivers will be unbound, and the device will be
+ * re-enumerated and probed all over again.
+ *
+ * Returns 0 if the reset succeeded, -ENODEV if the device has been
+ * flagged for logical disconnection, or some other negative error code
+ * if the reset wasn't even attempted.
+ *
+ * The caller must own the device lock.  For example, it's safe to use
+ * this from a driver probe() routine after downloading new firmware.
+ * For calls that might not occur during probe(), drivers should lock
+ * the device using usb_lock_device_for_reset().
+ */
+int usb_reset_device(struct usb_device *udev)
+{
+	struct usb_device		*parent_hdev = udev->parent;
+	struct usb_hub			*parent_hub;
+	struct usb_device_descriptor	descriptor = udev->descriptor;
+	struct usb_hub			*hub = NULL;
+	int 				i, ret = 0, port1 = -1;
+
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED) {
+		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
+				udev->state);
+		return -EINVAL;
+	}
+
+	if (!parent_hdev) {
+		/* this requires hcd-specific logic; see OHCI hc_restart() */
+		dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
+		return -EISDIR;
+	}
+
+	for (i = 0; i < parent_hdev->maxchild; i++)
+		if (parent_hdev->children[i] == udev) {
+			port1 = i + 1;
+			break;
+		}
+
+	if (port1 < 0) {
+		/* If this ever happens, it's very bad */
+		dev_err(&udev->dev, "Can't locate device's port!\n");
+		return -ENOENT;
+	}
+	parent_hub = hdev_to_hub(parent_hdev);
+
+	/* If we're resetting an active hub, take some special actions */
+	if (udev->actconfig &&
+			udev->actconfig->interface[0]->dev.driver ==
+				&hub_driver.driver &&
+			(hub = hdev_to_hub(udev)) != NULL) {
+		hub_pre_reset(hub);
+	}
+
+	set_bit(port1, parent_hub->busy_bits);
+	for (i = 0; i < SET_CONFIG_TRIES; ++i) {
+
+		/* ep0 maxpacket size may change; let the HCD know about it.
+		 * Other endpoints will be handled by re-enumeration. */
+		ep0_reinit(udev);
+		ret = hub_port_init(parent_hub, udev, port1, i);
+		if (ret >= 0)
+			break;
+	}
+	clear_bit(port1, parent_hub->busy_bits);
+	if (ret < 0)
+		goto re_enumerate;
+ 
+	/* Device might have changed firmware (DFU or similar) */
+	if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
+			|| config_descriptors_changed (udev)) {
+		dev_info(&udev->dev, "device firmware changed\n");
+		udev->descriptor = descriptor;	/* for disconnect() calls */
+		goto re_enumerate;
+  	}
+  
+	if (!udev->actconfig)
+		goto done;
+
+	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+			USB_REQ_SET_CONFIGURATION, 0,
+			udev->actconfig->desc.bConfigurationValue, 0,
+			NULL, 0, USB_CTRL_SET_TIMEOUT);
+	if (ret < 0) {
+		dev_err(&udev->dev,
+			"can't restore configuration #%d (error=%d)\n",
+			udev->actconfig->desc.bConfigurationValue, ret);
+		goto re_enumerate;
+  	}
+	usb_set_device_state(udev, USB_STATE_CONFIGURED);
+
+	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+		struct usb_interface *intf = udev->actconfig->interface[i];
+		struct usb_interface_descriptor *desc;
+
+		/* set_interface resets host side toggle even
+		 * for altsetting zero.  the interface may have no driver.
+		 */
+		desc = &intf->cur_altsetting->desc;
+		ret = usb_set_interface(udev, desc->bInterfaceNumber,
+			desc->bAlternateSetting);
+		if (ret < 0) {
+			dev_err(&udev->dev, "failed to restore interface %d "
+				"altsetting %d (error=%d)\n",
+				desc->bInterfaceNumber,
+				desc->bAlternateSetting,
+				ret);
+			goto re_enumerate;
+		}
+	}
+
+done:
+	if (hub)
+		hub_post_reset(hub);
+	return 0;
+ 
+re_enumerate:
+	hub_port_logical_disconnect(parent_hub, port1);
+	return -ENODEV;
+}