This commit was manufactured by cvs2svn to create tag
[linux-2.6.git] / drivers / usb / core / hub.c
index b13fe40..44cc03f 100644 (file)
 #include "hcd.h"
 #include "hub.h"
 
-/* Protect all struct usb_device state members */
+/* 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 spinlock_t device_state_lock = SPIN_LOCK_UNLOCKED;
 
-/* Wakes up khubd */
+/* khubd's worklist and its lock */
 static spinlock_t hub_event_lock = SPIN_LOCK_UNLOCKED;
-
 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);
 
@@ -53,6 +56,31 @@ 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 = 1;
+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)
@@ -75,9 +103,17 @@ static inline struct device *hubdev (struct usb_device *hdev)
 /* USB 2.0 spec Section 11.24.4.5 */
 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 {
-       return 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, HZ * USB_CTRL_GET_TIMEOUT);
+       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,
+                       HZ * USB_CTRL_GET_TIMEOUT);
+               if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
+                       return ret;
+       }
+       return -EINVAL;
 }
 
 /*
@@ -143,7 +179,7 @@ static void led_work (void *__hub)
        unsigned                changed = 0;
        int                     cursor = -1;
 
-       if (hdev->state != USB_STATE_CONFIGURED)
+       if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
                return;
 
        for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
@@ -226,6 +262,19 @@ static int get_port_status(struct usb_device *hdev, int port,
                data, sizeof(*data), HZ * USB_CTRL_GET_TIMEOUT);
 }
 
+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);
+}
+
+
 /* completion function, fires on port status changes and various faults */
 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 {
@@ -261,14 +310,12 @@ static void hub_irq(struct urb *urb, struct pt_regs *regs)
        hub->nerrors = 0;
 
        /* Something happened, let khubd figure it out */
-       spin_lock(&hub_event_lock);
-       if (list_empty(&hub->event_list)) {
-               list_add_tail(&hub->event_list, &hub_event_list);
-               wake_up(&khubd_wait);
-       }
-       spin_unlock(&hub_event_lock);
+       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->intf->dev, "resubmit --> %d\n", status);
@@ -381,6 +428,33 @@ static void hub_power_on(struct usb_hub *hub)
        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;
+       status = usb_submit_urb(hub->urb, GFP_NOIO);
+       if (status < 0)
+               dev_err(&hub->intf->dev, "activate --> %d\n", status);
+       if (hub->has_indicators && blinkenlights)
+               schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
+
+       /* scan all ports ASAP */
+       hub->event_bits[0] = ~0;
+       kick_khubd(hub);
+}
+
 static int hub_hub_status(struct usb_hub *hub,
                u16 *status, u16 *change)
 {
@@ -576,7 +650,7 @@ static int hub_configure(struct usb_hub *hub,
                dev_dbg(hub_dev, "%sover-current condition exists\n",
                        (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 
-       /* Start the interrupt endpoint */
+       /* set up the interrupt endpoint */
        pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
        maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 
@@ -594,24 +668,14 @@ static int hub_configure(struct usb_hub *hub,
                hub, endpoint->bInterval);
        hub->urb->transfer_dma = hub->buffer_dma;
        hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-       ret = usb_submit_urb(hub->urb, GFP_KERNEL);
-       if (ret) {
-               message = "couldn't submit status urb";
-               goto fail;
-       }
 
-       /* Wake up khubd */
-       wake_up(&khubd_wait);
-
-       /* maybe start cycling the hub leds */
-       if (hub->has_indicators && blinkenlights) {
-               set_port_led(hdev, 1, HUB_LED_GREEN);
+       /* maybe cycle the hub leds */
+       if (hub->has_indicators && blinkenlights)
                hub->indicator [0] = INDICATOR_CYCLE;
-               schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
-       }
 
        hub_power_on(hub);
-
+       hub->change_bits[0] = ~0;
+       hub_activate(hub);
        return 0;
 
 fail:
@@ -637,22 +701,14 @@ static void hub_disconnect(struct usb_interface *intf)
 
        usb_set_intfdata (intf, NULL);
 
-       if (hub->urb) {
-               usb_kill_urb(hub->urb);
-               usb_free_urb(hub->urb);
-               hub->urb = 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);
 
-       /* assuming we used keventd, it must quiesce too */
-       if (hub->has_indicators)
-               cancel_delayed_work (&hub->leds);
-       if (hub->has_indicators || hub->tt.hub)
-               flush_scheduled_work ();
-
        if (hub->descriptor) {
                kfree(hub->descriptor);
                hub->descriptor = NULL;
@@ -772,54 +828,74 @@ hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
        }
 }
 
-static int hub_reset(struct usb_hub *hub)
+/* caller has locked the hub device */
+static void hub_pre_reset(struct usb_device *hdev)
 {
-       struct usb_device *hdev = hub->hdev;
+       struct usb_hub *hub = usb_get_intfdata(hdev->actconfig->interface[0]);
        int i;
 
-       /* Disconnect any attached devices */
-       for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
+       for (i = 0; i < hdev->maxchild; ++i) {
                if (hdev->children[i])
                        usb_disconnect(&hdev->children[i]);
        }
+       hub_quiesce(hub);
+}
 
-       /* Attempt to reset the hub */
-       if (hub->urb)
-               usb_kill_urb(hub->urb);
-       else
-               return -1;
-
-       if (usb_reset_device(hdev))
-               return -1;
-
-       hub->urb->dev = hdev;                                                    
-       if (usb_submit_urb(hub->urb, GFP_KERNEL))
-               return -1;
+/* caller has locked the hub device */
+static void hub_post_reset(struct usb_device *hdev)
+{
+       struct usb_hub *hub = usb_get_intfdata(hdev->actconfig->interface[0]);
 
+       hub_activate(hub);
        hub_power_on(hub);
-
-       return 0;
 }
 
-/* FIXME!  This routine should be subsumed into hub_reset */
-static void hub_start_disconnect(struct usb_device *hdev)
+
+/* 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)
 {
-       struct usb_device *parent = hdev->parent;
-       int i;
+       int                     t;
+       struct usb_device       *hdev;
 
-       /* Find the device pointer to disconnect */
-       if (parent) {
-               for (i = 0; i < parent->maxchild; i++) {
-                       if (parent->children[i] == hdev) {
-                               usb_disconnect(&parent->children[i]);
-                               return;
-                       }
-               }
+       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;
        }
 
-       dev_err(&hdev->dev, "cannot disconnect hub!\n");
-}
+       /* 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;
+               }
+       }
+       usb_unlock_device(hdev);
+       return -ENODEV;
+}
 
 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 {
@@ -833,21 +909,24 @@ static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 }
 
 /**
- * usb_set_device_state - change a device's current state (usbcore-internal)
+ * 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_ protected by the udev->serialize semaphore.  This
+ * 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 the semaphore to be released.  Instead,
- * changes to the state must be protected by the device_state_lock spinlock.
+ * 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 descendant's states are also set
+ * 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,
@@ -864,6 +943,7 @@ void usb_set_device_state(struct usb_device *udev,
                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)
@@ -900,8 +980,9 @@ static void release_address(struct usb_device *udev)
  * @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 should be locked.
+ * 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.
  *
@@ -921,14 +1002,17 @@ void usb_disconnect(struct usb_device **pdev)
        }
 
        /* mark the device as inactive, so any further urb submissions for
-        * this device will fail.
+        * 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)
+       if (!udev->parent) {
                down(&usb_bus_list_lock);
-       down(&udev->serialize);
+               usb_lock_device(udev);
+       } else
+               down(&udev->serialize);
 
        dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
 
@@ -940,6 +1024,7 @@ void usb_disconnect(struct usb_device **pdev)
 
        /* 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);
 
@@ -957,9 +1042,11 @@ void usb_disconnect(struct usb_device **pdev)
        *pdev = NULL;
        spin_unlock_irq(&device_state_lock);
 
-       up(&udev->serialize);
-       if (!udev->parent)
+       if (!udev->parent) {
+               usb_unlock_device(udev);
                up(&usb_bus_list_lock);
+       } else
+               up(&udev->serialize);
 
        device_unregister(&udev->dev);
 }
@@ -982,11 +1069,19 @@ static int choose_configuration(struct usb_device *udev)
                                        ->altsetting->desc;
                        if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
                                continue;
-                       /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS */
+                       /* 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)
+                                       && desc->bInterfaceProtocol == 0xff) {
+                               c = udev->config[1].desc.bConfigurationValue;
                                continue;
+                       }
                        c = udev->config[i].desc.bConfigurationValue;
                        break;
                }
@@ -1016,6 +1111,10 @@ static inline void show_string(struct usb_device *udev, char *id, int index)
 {}
 #endif
 
+#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)
@@ -1065,6 +1164,79 @@ int usb_new_device(struct usb_device *udev)
                show_string(udev, "SerialNumber",
                                udev->descriptor.iSerialNumber);
 
+#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],
+                                       udev->config[0].desc.wTotalLength,
+                                       USB_DT_OTG, (void **) &desc) == 0) {
+                       if (desc->bmAttributes & USB_OTG_HNP) {
+                               unsigned                port;
+                               struct usb_device       *root = udev->parent;
+                               
+                               for (port = 0; port < root->maxchild; port++) {
+                                       if (root->children[port] == udev)
+                                               break;
+                               }
+                               port++;
+
+                               dev_info(&udev->dev,
+                                       "Dual-Role OTG device on %sHNP port\n",
+                                       (port == bus->otg_port)
+                                               ? "" : "non-");
+
+                               /* enable HNP before suspend, it's simpler */
+                               if (port == 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, HZ * 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 port, u32 state);
+                       err = __usb_suspend_device(udev,
+                                       udev->bus->otg_port - 1,
+                                       PM_SUSPEND_MEM);
+                       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) {
@@ -1127,7 +1299,8 @@ static int hub_port_status(struct usb_device *hdev, int port,
 #define PORT_RESET_TRIES       5
 #define SET_ADDRESS_TRIES      2
 #define GET_DESCRIPTOR_TRIES   2
-#define SET_CONFIG_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
@@ -1200,9 +1373,13 @@ static int hub_port_reset(struct usb_device *hdev, int port,
                        status = hub_port_wait_reset(hdev, port, udev, delay);
 
                /* return on disconnect or reset */
-               if (status == -ENOTCONN || status == 0) {
+               switch (status) {
+               case 0:
+               case -ENOTCONN:
+               case -ENODEV:
                        clear_port_feature(hdev,
                                port + 1, USB_PORT_FEAT_C_RESET);
+                       /* FIXME need disconnect() for NOTATTACHED device */
                        usb_set_device_state(udev, status
                                        ? USB_STATE_NOTATTACHED
                                        : USB_STATE_DEFAULT);
@@ -1226,9 +1403,10 @@ static int hub_port_disable(struct usb_device *hdev, int port)
 {
        int ret;
 
-       if (hdev->children[port])
+       if (hdev->children[port]) {
                usb_set_device_state(hdev->children[port],
                                USB_STATE_NOTATTACHED);
+       }
        ret = clear_port_feature(hdev, port + 1, USB_PORT_FEAT_ENABLE);
        if (ret)
                dev_err(hubdev(hdev), "cannot disable port %d (err = %d)\n",
@@ -1237,9 +1415,530 @@ static int hub_port_disable(struct usb_device *hdev, int port)
        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_device *hdev, int port)
+{
+       struct usb_hub *hub;
+
+       dev_dbg(hubdev(hdev), "logical disconnect on port %d\n", port + 1);
+       hub_port_disable(hdev, port);
+
+       /* 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.
+        */
+
+       hub = usb_get_intfdata(hdev->actconfig->interface[0]);
+       set_bit(port, hub->change_bits);
+       kick_khubd(hub);
+}
+
+
 #ifdef CONFIG_USB_SUSPEND
 
-       /* no USB_SUSPEND yet! */
+/*
+ * 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_device *hdev, int port)
+{
+       int                     status;
+       struct usb_device       *udev;
+
+       udev = hdev->children[port];
+       // dev_dbg(hubdev(hdev), "suspend port %d\n", port + 1);
+
+       /* 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(hdev, port + 1, USB_PORT_FEAT_SUSPEND);
+       if (status) {
+               dev_dbg(hubdev(hdev),
+                       "can't suspend port %d, status %d\n",
+                       port + 1, 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");
+               udev->state = 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.
+ */
+int __usb_suspend_device (struct usb_device *udev, int port, u32 state)
+{
+       int     status;
+
+       /* caller owns the udev device lock */
+       if (port < 0)
+               return port;
+
+       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)
+                               usb_set_device_state(udev,
+                                               USB_STATE_SUSPENDED);
+               } else
+                       status = -EOPNOTSUPP;
+       } else
+               status = hub_port_suspend(udev->parent, port);
+
+       return status;
+}
+EXPORT_SYMBOL(__usb_suspend_device);
+
+/**
+ * usb_suspend_device - suspend a usb device
+ * @udev: device that's no longer in active use
+ * @state: PM_SUSPEND_MEM 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, u32 state)
+{
+       int     port, status;
+
+       port = locktree(udev);
+       if (port < 0)
+               return port;
+
+       status = __usb_suspend_device(udev, port, 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.
+        */
+       udev->state = udev->actconfig
+               ? USB_STATE_CONFIGURED
+               : USB_STATE_ADDRESS;
+
+       /* 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_device *hdev, int port)
+{
+       int                     status;
+       struct usb_device       *udev;
+
+       udev = hdev->children[port];
+       // dev_dbg(hubdev(hdev), "resume port %d\n", port + 1);
+
+       /* see 7.1.7.7; affects power usage, but not budgeting */
+       status = clear_port_feature(hdev, port + 1, USB_PORT_FEAT_SUSPEND);
+       if (status) {
+               dev_dbg(&hdev->actconfig->interface[0]->dev,
+                       "can't resume port %d, status %d\n",
+                       port + 1, status);
+       } else {
+               u16             devstatus;
+               u16             portchange;
+
+               /* drive resume for at least 20 msec */
+               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(hdev, port,
+                               &devstatus, &portchange);
+               if (status < 0
+                               || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
+                               || (devstatus & USB_PORT_STAT_SUSPEND) != 0
+                               ) {
+                       dev_dbg(&hdev->actconfig->interface[0]->dev,
+                               "port %d status %04x.%04x after resume, %d\n",
+                               port + 1, portchange, devstatus, status);
+               } else {
+                       /* TRSMRCY = 10 msec */
+                       msleep(10);
+                       status = finish_port_resume(udev);
+               }
+       }
+       if (status < 0)
+               hub_port_logical_disconnect(hdev, port);
+
+       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                     port, status;
+
+       port = locktree(udev);
+       if (port < 0)
+               return port;
+
+       /* "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) {
+                       /* TRSMRCY = 10 msec */
+                       msleep(10);
+                       usb_set_device_state (udev, USB_STATE_CONFIGURED);
+                       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(udev->parent, port);
+       } 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, u32 state)
+{
+       struct usb_hub          *hub = usb_get_intfdata (intf);
+       struct usb_device       *hdev = hub->hdev;
+       unsigned                port;
+       int                     status;
+
+       /* stop khubd and related activity */
+       hub_quiesce(hub);
+
+       /* then suspend every port */
+       for (port = 0; port < hdev->maxchild; port++) {
+               struct usb_device       *udev;
+
+               udev = hdev->children [port];
+               if (!udev)
+                       continue;
+               down(&udev->serialize);
+               status = __usb_suspend_device(udev, port, state);
+               up(&udev->serialize);
+               if (status < 0)
+                       dev_dbg(&intf->dev, "suspend port %d --> %d\n",
+                               port, 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                port;
+       int                     status;
+
+       if (intf->dev.power.power_state == PM_SUSPEND_ON)
+               return 0;
+
+       for (port = 0; port < hdev->maxchild; port++) {
+               struct usb_device       *udev;
+               u16                     portstat, portchange;
+
+               udev = hdev->children [port];
+               status = hub_port_status(hdev, port, &portstat, &portchange);
+               if (status == 0) {
+                       if (portchange & USB_PORT_STAT_C_SUSPEND) {
+                               clear_port_feature(hdev, port + 1,
+                                       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(hdev, port);
+               else {
+                       status = finish_port_resume(udev);
+                       if (status < 0) {
+                               dev_dbg(&intf->dev, "resume port %d --> %d\n",
+                                       port + 1, status);
+                               hub_port_logical_disconnect(hdev, port);
+                       }
+               }
+               up(&udev->serialize);
+       }
+       intf->dev.power.power_state = PM_SUSPEND_ON;
+
+       hub_activate(hub);
+       return 0;
+}
 
 #else  /* !CONFIG_USB_SUSPEND */
 
@@ -1325,20 +2024,30 @@ static int hub_port_debounce(struct usb_device *hdev, int port)
        return portstatus;
 }
 
+#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_DEFAULT &&
-                       udev->state != USB_STATE_ADDRESS)
+       if (udev->state == USB_STATE_ADDRESS)
+               return 0;
+       if (udev->state != USB_STATE_DEFAULT)
                return -EINVAL;
-       retval = usb_control_msg(udev, (PIPE_CONTROL << 30) /* Address 0 */,
+       retval = usb_control_msg(udev, usb_sndaddr0pipe(),
                USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
                NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
-       if (retval == 0)
+       if (retval == 0) {
+               int m = udev->epmaxpacketin[0];
+
                usb_set_device_state(udev, USB_STATE_ADDRESS);
+               usb_disable_endpoint(udev, 0 + USB_DIR_IN);
+               usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
+               udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = m;
+       }
        return retval;
 }
 
@@ -1352,7 +2061,8 @@ static int hub_set_address(struct usb_device *udev)
  * pointers, it's not necessary to lock the device.
  */
 static int
-hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
+hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port,
+               int retry_counter)
 {
        static DECLARE_MUTEX(usb_address0_sem);
 
@@ -1387,6 +2097,7 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
                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.
@@ -1396,22 +2107,22 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
                i = 64;
                break;
        case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
-               /* to determine the ep0 maxpacket size, read the first 8
-                * bytes from the device descriptor to get bMaxPacketSize0;
-                * then correct our initial (small) guess.
+               /* to determine the ep0 maxpacket size, try to read
+                * the device descriptor to get bMaxPacketSize0 and
+                * then correct our initial guess.
                 */
-               // FALLTHROUGH
+               i = 64;
+               break;
        case USB_SPEED_LOW:             /* fixed at 8 */
                i = 8;
                break;
        default:
                goto fail;
        }
-       udev->epmaxpacketin [0] = i;
-       udev->epmaxpacketout[0] = i;
+       udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = i;
  
        dev_info (&udev->dev,
-                       "%s %s speed USB device using address %d\n",
+                       "%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;
@@ -1419,6 +2130,7 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
                        case USB_SPEED_HIGH:    speed = "high"; break;
                        default:                speed = "?";    break;
                        }; speed;}),
+                       udev->bus->controller->driver->name,
                        udev->devnum);
 
        /* Set up TT records, if needed  */
@@ -1439,11 +2151,59 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
         * this area, and this is how Linux has done it for ages.
         * Change it cautiously.
         *
-        * NOTE:  Windows gets the descriptor first, seemingly to help
-        * work around device bugs like "can't use addresses with bit 3
-        * set in certain configurations".  Yes, really.
+        * 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) {
+       for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
+               if (USE_NEW_SCHEME(retry_counter)) {
+                       struct usb_device_descriptor *buf;
+
+#define GET_DESCRIPTOR_BUFSIZE 64
+                       buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
+                       if (!buf) {
+                               retval = -ENOMEM;
+                               continue;
+                       }
+                       buf->bMaxPacketSize0 = 0;
+
+                       /* 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.
+                        */
+                       j = usb_control_msg(udev, usb_rcvaddr0pipe(),
+                                       USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
+                                       USB_DT_DEVICE << 8, 0,
+                                       buf, GET_DESCRIPTOR_BUFSIZE,
+                                       (i ? HZ * USB_CTRL_GET_TIMEOUT : HZ));
+                       udev->descriptor.bMaxPacketSize0 =
+                                       buf->bMaxPacketSize0;
+                       kfree(buf);
+
+                       retval = hub_port_reset(hdev, port, 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 (udev->descriptor.bMaxPacketSize0 == 0) {
+                               dev_err(&udev->dev, "device descriptor "
+                                               "read/%s, error %d\n",
+                                               "64", j);
+                               retval = -EMSGSIZE;
+                               continue;
+                       }
+#undef GET_DESCRIPTOR_BUFSIZE
+               }
+
                for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
                        retval = hub_set_address(udev);
                        if (retval >= 0)
@@ -1462,27 +2222,31 @@ hub_port_init (struct usb_device *hdev, struct usb_device *udev, int port)
                 *  - 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)
+               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;
-               msleep(100);
+               }
        }
-       if (retval != 8) {
-               dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
-                               "8", retval);
-               if (retval >= 0)
-                       retval = -EMSGSIZE;
+       if (retval)
                goto fail;
-       }
-       if (udev->speed == USB_SPEED_FULL
-                       && (udev->epmaxpacketin [0]
-                               != udev->descriptor.bMaxPacketSize0)) {
+
+       /* Should we verify that the value is valid? */
+       i = udev->descriptor.bMaxPacketSize0;
+       if (udev->epmaxpacketin[0] != i) {
+               dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
                usb_disable_endpoint(udev, 0 + USB_DIR_IN);
                usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
-               usb_endpoint_running(udev, 0, 1);
-               usb_endpoint_running(udev, 0, 0);
-               udev->epmaxpacketin [0] = udev->descriptor.bMaxPacketSize0;
-               udev->epmaxpacketout[0] = udev->descriptor.bMaxPacketSize0;
+               udev->epmaxpacketin[0] = udev->epmaxpacketout[0] = i;
        }
   
        retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
@@ -1574,6 +2338,7 @@ hub_power_remaining (struct usb_hub *hub)
  *     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 port,
                                        u16 portstatus, u16 portchange)
@@ -1596,6 +2361,12 @@ static void hub_port_connect_change(struct usb_hub *hub, int port,
                usb_disconnect(&hdev->children[port]);
        clear_bit(port, 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(hdev, port);
                if (status < 0) {
@@ -1621,6 +2392,15 @@ static void hub_port_connect_change(struct usb_hub *hub, int port,
                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(hdev, port);
+               if (status < 0)
+                       dev_dbg(hub_dev, "can't clear suspend on port %d; %d\n", port+1, status);
+       }
+#endif
+
        for (i = 0; i < SET_CONFIG_TRIES; i++) {
                struct usb_device *udev;
 
@@ -1645,7 +2425,7 @@ static void hub_port_connect_change(struct usb_hub *hub, int port,
                }
 
                /* reset and get descriptor */
-               status = hub_port_init(hdev, udev, port);
+               status = hub_port_init(hdev, udev, port, i);
                if (status < 0)
                        goto loop;
 
@@ -1778,9 +2558,18 @@ static void hub_events(void)
                usb_get_dev(hdev);
                spin_unlock_irq(&hub_event_lock);
 
+               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]);
+
                /* Lock the device, then check to see if we were
                 * disconnected while waiting for the lock to succeed. */
-               down(&hdev->serialize);
+               if (locktree(hdev) < 0)
+                       break;
                if (hdev->state != USB_STATE_CONFIGURED ||
                                !hdev->actconfig ||
                                hub != usb_get_intfdata(
@@ -1791,10 +2580,10 @@ static void hub_events(void)
                        dev_dbg (hub_dev, "resetting for error %d\n",
                                hub->error);
 
-                       if (hub_reset(hub)) {
+                       ret = usb_reset_device(hdev);
+                       if (ret) {
                                dev_dbg (hub_dev,
-                                       "can't reset; disconnecting\n");
-                               hub_start_disconnect(hdev);
+                                       "error resetting hub: %d\n", ret);
                                goto loop;
                        }
 
@@ -1850,15 +2639,17 @@ static void hub_events(void)
                        if (portchange & USB_PORT_STAT_C_SUSPEND) {
                                clear_port_feature(hdev, i + 1,
                                        USB_PORT_FEAT_C_SUSPEND);
-                               if (hdev->children[i])
+                               if (hdev->children[i]) {
                                        ret = remote_wakeup(hdev->children[i]);
-                               else
+                                       if (ret < 0)
+                                               connect_change = 1;
+                               } else {
                                        ret = -ENODEV;
+                                       hub_port_disable(hdev, i);
+                               }
                                dev_dbg (hub_dev,
                                        "resume on port %d, status %d\n",
                                        i + 1, ret);
-                               if (ret < 0)
-                                       ret = hub_port_disable(hdev, i);
                        }
                        
                        if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
@@ -1902,7 +2693,7 @@ static void hub_events(void)
                }
 
 loop:
-               up(&hdev->serialize);
+               usb_unlock_device(hdev);
                usb_put_dev(hdev);
 
         } /* end while (1) */
@@ -2034,7 +2825,7 @@ static int config_descriptors_changed(struct usb_device *udev)
 }
 
 /**
- * usb_reset_devce - perform a USB port reset to reinitialize a device
+ * 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
@@ -2055,13 +2846,15 @@ static int config_descriptors_changed(struct usb_device *udev)
  *
  * 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)
+int usb_reset_device(struct usb_device *udev)
 {
        struct usb_device *parent = udev->parent;
        struct usb_device_descriptor descriptor = udev->descriptor;
-       int i, ret, port = -1;
-       struct usb_hub *hub;
+       int i, ret = 0, port = -1;
+       int udev_is_a_hub = 0;
 
        if (udev->state == USB_STATE_NOTATTACHED ||
                        udev->state == USB_STATE_SUSPENDED) {
@@ -2070,13 +2863,9 @@ int __usb_reset_device(struct usb_device *udev)
                return -EINVAL;
        }
 
-       /* FIXME: This should be legal for regular hubs.  Root hubs may
-        * have special requirements. */
-       if (udev->maxchild) {
-               /* this requires hub- or hcd-specific logic;
-                * see hub_reset() and OHCI hc_restart()
-                */
-               dev_dbg(&udev->dev, "%s for hub!\n", __FUNCTION__);
+       if (!parent) {
+               /* this requires hcd-specific logic; see OHCI hc_restart() */
+               dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
                return -EISDIR;
        }
 
@@ -2092,7 +2881,24 @@ int __usb_reset_device(struct usb_device *udev)
                return -ENOENT;
        }
 
-       ret = hub_port_init(parent, udev, port);
+       /* If we're resetting an active hub, take some special actions */
+       if (udev->actconfig &&
+                       udev->actconfig->interface[0]->dev.driver ==
+                       &hub_driver.driver) {
+               udev_is_a_hub = 1;
+               hub_pre_reset(udev);
+       }
+
+       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. */
+               usb_disable_endpoint(udev, 0 + USB_DIR_IN);
+               usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
+               ret = hub_port_init(parent, udev, port, i);
+               if (ret >= 0)
+                       break;
+       }
        if (ret < 0)
                goto re_enumerate;
  
@@ -2105,7 +2911,7 @@ int __usb_reset_device(struct usb_device *udev)
        }
   
        if (!udev->actconfig)
-               return 0;
+               goto done;
 
        ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                        USB_REQ_SET_CONFIGURATION, 0,
@@ -2123,7 +2929,7 @@ int __usb_reset_device(struct usb_device *udev)
                struct usb_interface *intf = udev->actconfig->interface[i];
                struct usb_interface_descriptor *desc;
 
-               /* set_interface resets host side toggle and halt status even
+               /* set_interface resets host side toggle even
                 * for altsetting zero.  the interface may have no driver.
                 */
                desc = &intf->cur_altsetting->desc;
@@ -2139,32 +2945,12 @@ int __usb_reset_device(struct usb_device *udev)
                }
        }
 
+done:
+       if (udev_is_a_hub)
+               hub_post_reset(udev);
        return 0;
  
 re_enumerate:
-       hub_port_disable(parent, port);
-
-       hub = usb_get_intfdata(parent->actconfig->interface[0]);
-       set_bit(port, hub->change_bits);
-
-       spin_lock_irq(&hub_event_lock);
-       if (list_empty(&hub->event_list)) {
-               list_add_tail(&hub->event_list, &hub_event_list);
-               wake_up(&khubd_wait);
-       }
-       spin_unlock_irq(&hub_event_lock);
-
+       hub_port_logical_disconnect(parent, port);
        return -ENODEV;
 }
-EXPORT_SYMBOL(__usb_reset_device);
-
-int usb_reset_device(struct usb_device *udev)
-{
-       int r;
-       
-       down(&udev->serialize);
-       r = __usb_reset_device(udev);
-       up(&udev->serialize);
-
-       return r;
-}