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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /*
  * 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)
  *
  * Released under the GPLv2 only.
  */
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/completion.h>
 #include <linux/sched/mm.h>
 #include <linux/list.h>
 #include <linux/slab.h>
 #include <linux/kcov.h>
 #include <linux/ioctl.h>
 #include <linux/usb.h>
 #include <linux/usbdevice_fs.h>
 #include <linux/usb/hcd.h>
 #include <linux/usb/onboard_hub.h>
 #include <linux/usb/otg.h>
 #include <linux/usb/quirks.h>
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
 #include <linux/random.h>
 #include <linux/pm_qos.h>
 #include <linux/kobject.h>
 
 #include <linux/bitfield.h>
 #include <linux/uaccess.h>
 #include <asm/byteorder.h>
 
 #include "hub.h"
 #include "otg_productlist.h"
 
 #define USB_VENDOR_GENESYS_LOGIC        0x05e3
 #define USB_VENDOR_SMSC             0x0424
 #define USB_PRODUCT_USB5534B            0x5534
 #define USB_VENDOR_CYPRESS          0x04b4
 #define USB_PRODUCT_CY7C65632           0x6570
 #define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND    0x01
 #define HUB_QUIRK_DISABLE_AUTOSUSPEND       0x02
 
 #define USB_TP_TRANSMISSION_DELAY   40  /* ns */
 #define USB_TP_TRANSMISSION_DELAY_MAX   65535   /* ns */
 #define USB_PING_RESPONSE_TIME      400 /* ns */
 
 /* Protect struct usb_device->state and ->children members
  * Note: Both are also protected by ->dev.sem, except that ->state can
  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
 static DEFINE_SPINLOCK(device_state_lock);
 
 /* workqueue to process hub events */
 static struct workqueue_struct *hub_wq;
 static void hub_event(struct work_struct *work);
 
 /* synchronize hub-port add/remove and peering operations */
 DEFINE_MUTEX(usb_port_peer_mutex);
 
 /* cycle leds on hubs that aren't blinking for attention */
 static bool blinkenlights;
 module_param(blinkenlights, bool, S_IRUGO);
 MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
 
 /*
  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  * 10 seconds to send reply for the initial 64-byte descriptor request.
  */
 /* define initial 64-byte descriptor request timeout in milliseconds */
 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(initial_descriptor_timeout,
         "initial 64-byte descriptor request timeout in milliseconds "
         "(default 5000 - 5.0 seconds)");
 
 /*
  * 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 bool old_scheme_first;
 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(old_scheme_first,
          "start with the old device initialization scheme");
 
 static bool use_both_schemes = true;
 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");
 
 /* Mutual exclusion for EHCI CF initialization.  This interferes with
  * port reset on some companion controllers.
  */
 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 
 #define HUB_DEBOUNCE_TIMEOUT    2000
 #define HUB_DEBOUNCE_STEP     25
 #define HUB_DEBOUNCE_STABLE  100
 
 static void hub_release(struct kref *kref);
 static int usb_reset_and_verify_device(struct usb_device *udev);
 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
         u16 portstatus);
 
 static inline char *portspeed(struct usb_hub *hub, int portstatus)
 {
     if (hub_is_superspeedplus(hub->hdev))
         return "10.0 Gb/s";
     if (hub_is_superspeed(hub->hdev))
         return "5.0 Gb/s";
     if (portstatus & USB_PORT_STAT_HIGH_SPEED)
         return "480 Mb/s";
     else if (portstatus & USB_PORT_STAT_LOW_SPEED)
         return "1.5 Mb/s";
     else
         return "12 Mb/s";
 }
 
 /* Note that hdev or one of its children must be locked! */
 struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 {
     if (!hdev || !hdev->actconfig || !hdev->maxchild)
         return NULL;
     return usb_get_intfdata(hdev->actconfig->interface[0]);
 }
 
 int usb_device_supports_lpm(struct usb_device *udev)
 {
     /* Some devices have trouble with LPM */
     if (udev->quirks & USB_QUIRK_NO_LPM)
         return 0;
 
     /* USB 2.1 (and greater) devices indicate LPM support through
      * their USB 2.0 Extended Capabilities BOS descriptor.
      */
     if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
         if (udev->bos->ext_cap &&
             (USB_LPM_SUPPORT &
              le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
             return 1;
         return 0;
     }
 
     /*
      * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
      * However, there are some that don't, and they set the U1/U2 exit
      * latencies to zero.
      */
     if (!udev->bos->ss_cap) {
         dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
         return 0;
     }
 
     if (udev->bos->ss_cap->bU1devExitLat == 0 &&
             udev->bos->ss_cap->bU2DevExitLat == 0) {
         if (udev->parent)
             dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
         else
             dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
         return 0;
     }
 
     if (!udev->parent || udev->parent->lpm_capable)
         return 1;
     return 0;
 }
 
 /*
  * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
  * U1/U2, send a PING to the device and receive a PING_RESPONSE.
  * See USB 3.1 section C.1.5.2
  */
 static void usb_set_lpm_mel(struct usb_device *udev,
         struct usb3_lpm_parameters *udev_lpm_params,
         unsigned int udev_exit_latency,
         struct usb_hub *hub,
         struct usb3_lpm_parameters *hub_lpm_params,
         unsigned int hub_exit_latency)
 {
     unsigned int total_mel;
 
     /*
      * tMEL1. time to transition path from host to device into U0.
      * MEL for parent already contains the delay up to parent, so only add
      * the exit latency for the last link (pick the slower exit latency),
      * and the hub header decode latency. See USB 3.1 section C 2.2.1
      * Store MEL in nanoseconds
      */
     total_mel = hub_lpm_params->mel +
         max(udev_exit_latency, hub_exit_latency) * 1000 +
         hub->descriptor->u.ss.bHubHdrDecLat * 100;
 
     /*
      * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
      * each link + wHubDelay for each hub. Add only for last link.
      * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
      * Multiply by 2 to include it as well.
      */
     total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
               USB_TP_TRANSMISSION_DELAY) * 2;
 
     /*
      * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
      * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
      * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
      * Size DP.
      * Note these delays should be added only once for the entire path, so
      * add them to the MEL of the device connected to the roothub.
      */
     if (!hub->hdev->parent)
         total_mel += USB_PING_RESPONSE_TIME + 2100;
 
     udev_lpm_params->mel = total_mel;
 }
 
 /*
  * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
  * a transition from either U1 or U2.
  */
 static void usb_set_lpm_pel(struct usb_device *udev,
         struct usb3_lpm_parameters *udev_lpm_params,
         unsigned int udev_exit_latency,
         struct usb_hub *hub,
         struct usb3_lpm_parameters *hub_lpm_params,
         unsigned int hub_exit_latency,
         unsigned int port_to_port_exit_latency)
 {
     unsigned int first_link_pel;
     unsigned int hub_pel;
 
     /*
      * First, the device sends an LFPS to transition the link between the
      * device and the parent hub into U0.  The exit latency is the bigger of
      * the device exit latency or the hub exit latency.
      */
     if (udev_exit_latency > hub_exit_latency)
         first_link_pel = udev_exit_latency * 1000;
     else
         first_link_pel = hub_exit_latency * 1000;
 
     /*
      * When the hub starts to receive the LFPS, there is a slight delay for
      * it to figure out that one of the ports is sending an LFPS.  Then it
      * will forward the LFPS to its upstream link.  The exit latency is the
      * delay, plus the PEL that we calculated for this hub.
      */
     hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 
     /*
      * According to figure C-7 in the USB 3.0 spec, the PEL for this device
      * is the greater of the two exit latencies.
      */
     if (first_link_pel > hub_pel)
         udev_lpm_params->pel = first_link_pel;
     else
         udev_lpm_params->pel = hub_pel;
 }
 
 /*
  * Set the System Exit Latency (SEL) to indicate the total worst-case time from
  * when a device initiates a transition to U0, until when it will receive the
  * first packet from the host controller.
  *
  * Section C.1.5.1 describes the four components to this:
  *  - t1: device PEL
  *  - t2: time for the ERDY to make it from the device to the host.
  *  - t3: a host-specific delay to process the ERDY.
  *  - t4: time for the packet to make it from the host to the device.
  *
  * t3 is specific to both the xHCI host and the platform the host is integrated
  * into.  The Intel HW folks have said it's negligible, FIXME if a different
  * vendor says otherwise.
  */
 static void usb_set_lpm_sel(struct usb_device *udev,
         struct usb3_lpm_parameters *udev_lpm_params)
 {
     struct usb_device *parent;
     unsigned int num_hubs;
     unsigned int total_sel;
 
     /* t1 = device PEL */
     total_sel = udev_lpm_params->pel;
     /* How many external hubs are in between the device & the root port. */
     for (parent = udev->parent, num_hubs = 0; parent->parent;
             parent = parent->parent)
         num_hubs++;
     /* t2 = 2.1us + 250ns * (num_hubs - 1) */
     if (num_hubs > 0)
         total_sel += 2100 + 250 * (num_hubs - 1);
 
     /* t4 = 250ns * num_hubs */
     total_sel += 250 * num_hubs;
 
     udev_lpm_params->sel = total_sel;
 }
 
 static void usb_set_lpm_parameters(struct usb_device *udev)
 {
     struct usb_hub *hub;
     unsigned int port_to_port_delay;
     unsigned int udev_u1_del;
     unsigned int udev_u2_del;
     unsigned int hub_u1_del;
     unsigned int hub_u2_del;
 
     if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
         return;
 
     hub = usb_hub_to_struct_hub(udev->parent);
     /* It doesn't take time to transition the roothub into U0, since it
      * doesn't have an upstream link.
      */
     if (!hub)
         return;
 
     udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
     udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
     hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
     hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 
     usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
             hub, &udev->parent->u1_params, hub_u1_del);
 
     usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
             hub, &udev->parent->u2_params, hub_u2_del);
 
     /*
      * Appendix C, section C.2.2.2, says that there is a slight delay from
      * when the parent hub notices the downstream port is trying to
      * transition to U0 to when the hub initiates a U0 transition on its
      * upstream port.  The section says the delays are tPort2PortU1EL and
      * tPort2PortU2EL, but it doesn't define what they are.
      *
      * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
      * about the same delays.  Use the maximum delay calculations from those
      * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
      * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
      * assume the device exit latencies they are talking about are the hub
      * exit latencies.
      *
      * What do we do if the U2 exit latency is less than the U1 exit
      * latency?  It's possible, although not likely...
      */
     port_to_port_delay = 1;
 
     usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
             hub, &udev->parent->u1_params, hub_u1_del,
             port_to_port_delay);
 
     if (hub_u2_del > hub_u1_del)
         port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
     else
         port_to_port_delay = 1 + hub_u1_del;
 
     usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
             hub, &udev->parent->u2_params, hub_u2_del,
             port_to_port_delay);
 
     /* Now that we've got PEL, calculate SEL. */
     usb_set_lpm_sel(udev, &udev->u1_params);
     usb_set_lpm_sel(udev, &udev->u2_params);
 }
 
 /* USB 2.0 spec Section 11.24.4.5 */
 static int get_hub_descriptor(struct usb_device *hdev,
         struct usb_hub_descriptor *desc)
 {
     int i, ret, size;
     unsigned dtype;
 
     if (hub_is_superspeed(hdev)) {
         dtype = USB_DT_SS_HUB;
         size = USB_DT_SS_HUB_SIZE;
     } else {
         dtype = USB_DT_HUB;
         size = sizeof(struct usb_hub_descriptor);
     }
 
     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,
             dtype << 8, 0, desc, size,
             USB_CTRL_GET_TIMEOUT);
         if (hub_is_superspeed(hdev)) {
             if (ret == size)
                 return ret;
         } else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
             /* Make sure we have the DeviceRemovable field. */
             size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
             if (ret < size)
                 return -EMSGSIZE;
             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
  */
 int usb_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);
 }
 
 static char *to_led_name(int selector)
 {
     switch (selector) {
     case HUB_LED_AMBER:
         return "amber";
     case HUB_LED_GREEN:
         return "green";
     case HUB_LED_OFF:
         return "off";
     case HUB_LED_AUTO:
         return "auto";
     default:
         return "??";
     }
 }
 
 /*
  * 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)
 {
     struct usb_port *port_dev = hub->ports[port1 - 1];
     int status;
 
     status = set_port_feature(hub->hdev, (selector << 8) | port1,
             USB_PORT_FEAT_INDICATOR);
     dev_dbg(&port_dev->dev, "indicator %s status %d\n",
         to_led_name(selector), status);
 }
 
 #define LED_CYCLE_PERIOD    ((2*HZ)/3)
 
 static void led_work(struct work_struct *work)
 {
     struct usb_hub      *hub =
         container_of(work, struct usb_hub, leds.work);
     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 < hdev->maxchild; 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 %= hdev->maxchild;
         set_port_led(hub, cursor + 1, HUB_LED_GREEN);
         hub->indicator[cursor] = INDICATOR_CYCLE;
         changed++;
     }
     if (changed)
         queue_delayed_work(system_power_efficient_wq,
                 &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 || status == -EPIPE); 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
  * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
  */
 static int get_port_status(struct usb_device *hdev, int port1,
                void *data, u16 value, u16 length)
 {
     int i, status = -ETIMEDOUT;
 
     for (i = 0; i < USB_STS_RETRIES &&
             (status == -ETIMEDOUT || status == -EPIPE); i++) {
         status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
             USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
             port1, data, length, USB_STS_TIMEOUT);
     }
     return status;
 }
 
 static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
                    u16 *status, u16 *change, u32 *ext_status)
 {
     int ret;
     int len = 4;
 
     if (type != HUB_PORT_STATUS)
         len = 8;
 
     mutex_lock(&hub->status_mutex);
     ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
     if (ret < len) {
         if (ret != -ENODEV)
             dev_err(hub->intfdev,
                 "%s failed (err = %d)\n", __func__, ret);
         if (ret >= 0)
             ret = -EIO;
     } else {
         *status = le16_to_cpu(hub->status->port.wPortStatus);
         *change = le16_to_cpu(hub->status->port.wPortChange);
         if (type != HUB_PORT_STATUS && ext_status)
             *ext_status = le32_to_cpu(
                 hub->status->port.dwExtPortStatus);
         ret = 0;
     }
     mutex_unlock(&hub->status_mutex);
     return ret;
 }
 
 int usb_hub_port_status(struct usb_hub *hub, int port1,
         u16 *status, u16 *change)
 {
     return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
                    status, change, NULL);
 }
 
 static void hub_resubmit_irq_urb(struct usb_hub *hub)
 {
     unsigned long flags;
     int status;
 
     spin_lock_irqsave(&hub->irq_urb_lock, flags);
 
     if (hub->quiescing) {
         spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
         return;
     }
 
     status = usb_submit_urb(hub->urb, GFP_ATOMIC);
     if (status && status != -ENODEV && status != -EPERM &&
         status != -ESHUTDOWN) {
         dev_err(hub->intfdev, "resubmit --> %d\n", status);
         mod_timer(&hub->irq_urb_retry, jiffies + HZ);
     }
 
     spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 }
 
 static void hub_retry_irq_urb(struct timer_list *t)
 {
     struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 
     hub_resubmit_irq_urb(hub);
 }
 
 
 static void kick_hub_wq(struct usb_hub *hub)
 {
     struct usb_interface *intf;
 
     if (hub->disconnected || work_pending(&hub->events))
         return;
 
     /*
      * Suppress autosuspend until the event is proceed.
      *
      * Be careful and make sure that the symmetric operation is
      * always called. We are here only when there is no pending
      * work for this hub. Therefore put the interface either when
      * the new work is called or when it is canceled.
      */
     intf = to_usb_interface(hub->intfdev);
     usb_autopm_get_interface_no_resume(intf);
     kref_get(&hub->kref);
 
     if (queue_work(hub_wq, &hub->events))
         return;
 
     /* the work has already been scheduled */
     usb_autopm_put_interface_async(intf);
     kref_put(&hub->kref, hub_release);
 }
 
 void usb_kick_hub_wq(struct usb_device *hdev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 
     if (hub)
         kick_hub_wq(hub);
 }
 
 /*
  * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
  * Notification, which indicates it had initiated remote wakeup.
  *
  * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
  * device initiates resume, so the USB core will not receive notice of the
  * resume through the normal hub interrupt URB.
  */
 void usb_wakeup_notification(struct usb_device *hdev,
         unsigned int portnum)
 {
     struct usb_hub *hub;
     struct usb_port *port_dev;
 
     if (!hdev)
         return;
 
     hub = usb_hub_to_struct_hub(hdev);
     if (hub) {
         port_dev = hub->ports[portnum - 1];
         if (port_dev && port_dev->child)
             pm_wakeup_event(&port_dev->child->dev, 0);
 
         set_bit(portnum, hub->wakeup_bits);
         kick_hub_wq(hub);
     }
 }
 EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 
 /* completion function, fires on port status changes and various faults */
 static void hub_irq(struct urb *urb)
 {
     struct usb_hub *hub = urb->context;
     int status = urb->status;
     unsigned i;
     unsigned long bits;
 
     switch (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", status);
         if ((++hub->nerrors < 10) || hub->error)
             goto resubmit;
         hub->error = status;
         fallthrough;
 
     /* let hub_wq 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 hub_wq figure it out */
     kick_hub_wq(hub);
 
 resubmit:
     hub_resubmit_irq_urb(hub);
 }
 
 /* USB 2.0 spec Section 11.24.2.3 */
 static inline int
 hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 {
     /* Need to clear both directions for control ep */
     if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
             USB_ENDPOINT_XFER_CONTROL) {
         int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
                 HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
                 devinfo ^ 0x8000, tt, NULL, 0, 1000);
         if (status)
             return status;
     }
     return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
                    HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
                    tt, NULL, 0, 1000);
 }
 
 /*
  * enumeration blocks hub_wq 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_work(struct work_struct *work)
 {
     struct usb_hub      *hub =
         container_of(work, struct usb_hub, tt.clear_work);
     unsigned long       flags;
 
     spin_lock_irqsave(&hub->tt.lock, flags);
     while (!list_empty(&hub->tt.clear_list)) {
         struct list_head    *next;
         struct usb_tt_clear *clear;
         struct usb_device   *hdev = hub->hdev;
         const struct hc_driver  *drv;
         int         status;
 
         next = hub->tt.clear_list.next;
         clear = list_entry(next, 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);
         if (status && status != -ENODEV)
             dev_err(&hdev->dev,
                 "clear tt %d (%04x) error %d\n",
                 clear->tt, clear->devinfo, status);
 
         /* Tell the HCD, even if the operation failed */
         drv = clear->hcd->driver;
         if (drv->clear_tt_buffer_complete)
             (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 
         kfree(clear);
         spin_lock_irqsave(&hub->tt.lock, flags);
     }
     spin_unlock_irqrestore(&hub->tt.lock, flags);
 }
 
 /**
  * usb_hub_set_port_power - control hub port's power state
  * @hdev: USB device belonging to the usb hub
  * @hub: target hub
  * @port1: port index
  * @set: expected status
  *
  * call this function to control port's power via setting or
  * clearing the port's PORT_POWER feature.
  *
  * Return: 0 if successful. A negative error code otherwise.
  */
 int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
                int port1, bool set)
 {
     int ret;
 
     if (set)
         ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
     else
         ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 
     if (ret)
         return ret;
 
     if (set)
         set_bit(port1, hub->power_bits);
     else
         clear_bit(port1, hub->power_bits);
     return 0;
 }
 
 /**
  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
  * @urb: an URB associated with the failed or incomplete split 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.
  *
  * Return: 0 if successful. A negative error code otherwise.
  */
 int usb_hub_clear_tt_buffer(struct urb *urb)
 {
     struct usb_device   *udev = urb->dev;
     int         pipe = urb->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.
      */
     clear = kmalloc(sizeof *clear, GFP_ATOMIC);
     if (clear == NULL) {
         dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
         /* FIXME recover somehow ... RESET_TT? */
         return -ENOMEM;
     }
 
     /* info that CLEAR_TT_BUFFER needs */
     clear->tt = tt->multi ? udev->ttport : 1;
     clear->devinfo = usb_pipeendpoint (pipe);
     clear->devinfo |= ((u16)udev->devaddr) << 4;
     clear->devinfo |= usb_pipecontrol(pipe)
             ? (USB_ENDPOINT_XFER_CONTROL << 11)
             : (USB_ENDPOINT_XFER_BULK << 11);
     if (usb_pipein(pipe))
         clear->devinfo |= 1 << 15;
 
     /* info for completion callback */
     clear->hcd = bus_to_hcd(udev->bus);
     clear->ep = urb->ep;
 
     /* 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->clear_work);
     spin_unlock_irqrestore(&tt->lock, flags);
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 
 static void hub_power_on(struct usb_hub *hub, bool do_delay)
 {
     int port1;
 
     /* Enable power on each port.  Some hubs have reserved values
      * of LPSM (> 2) in their descriptors, even though they are
      * USB 2.0 hubs.  Some hubs do not implement port-power switching
      * but only emulate it.  In all cases, the ports won't work
      * unless we send these messages to the hub.
      */
     if (hub_is_port_power_switchable(hub))
         dev_dbg(hub->intfdev, "enabling power on all ports\n");
     else
         dev_dbg(hub->intfdev, "trying to enable port power on "
                 "non-switchable hub\n");
     for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
         if (test_bit(port1, hub->power_bits))
             set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
         else
             usb_clear_port_feature(hub->hdev, port1,
                         USB_PORT_FEAT_POWER);
     if (do_delay)
         msleep(hub_power_on_good_delay(hub));
 }
 
 static int hub_hub_status(struct usb_hub *hub,
         u16 *status, u16 *change)
 {
     int ret;
 
     mutex_lock(&hub->status_mutex);
     ret = get_hub_status(hub->hdev, &hub->status->hub);
     if (ret < 0) {
         if (ret != -ENODEV)
             dev_err(hub->intfdev,
                 "%s failed (err = %d)\n", __func__, ret);
     } else {
         *status = le16_to_cpu(hub->status->hub.wHubStatus);
         *change = le16_to_cpu(hub->status->hub.wHubChange);
         ret = 0;
     }
     mutex_unlock(&hub->status_mutex);
     return ret;
 }
 
 static int hub_set_port_link_state(struct usb_hub *hub, int port1,
             unsigned int link_status)
 {
     return set_port_feature(hub->hdev,
             port1 | (link_status << 3),
             USB_PORT_FEAT_LINK_STATE);
 }
 
 /*
  * Disable a port and mark a logical connect-change event, so that some
  * time later hub_wq 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->ports[port1 - 1]->dev, "logical disconnect\n");
     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
      *  - ... new call, TBD ...
      * That's easy if this hub can switch power per-port, and
      * hub_wq reactivates the port later (timer, SRP, etc).
      * Powerdown must be optional, because of reset/DFU.
      */
 
     set_bit(port1, hub->change_bits);
     kick_hub_wq(hub);
 }
 
 /**
  * usb_remove_device - disable a device's port on its parent hub
  * @udev: device to be disabled and removed
  * Context: @udev locked, must be able to sleep.
  *
  * After @udev's port has been disabled, hub_wq is notified and it will
  * see that the device has been disconnected.  When the device is
  * physically unplugged and something is plugged in, the events will
  * be received and processed normally.
  *
  * Return: 0 if successful. A negative error code otherwise.
  */
 int usb_remove_device(struct usb_device *udev)
 {
     struct usb_hub *hub;
     struct usb_interface *intf;
     int ret;
 
     if (!udev->parent)  /* Can't remove a root hub */
         return -EINVAL;
     hub = usb_hub_to_struct_hub(udev->parent);
     intf = to_usb_interface(hub->intfdev);
 
     ret = usb_autopm_get_interface(intf);
     if (ret < 0)
         return ret;
 
     set_bit(udev->portnum, hub->removed_bits);
     hub_port_logical_disconnect(hub, udev->portnum);
     usb_autopm_put_interface(intf);
     return 0;
 }
 
 enum hub_activation_type {
     HUB_INIT, HUB_INIT2, HUB_INIT3,     /* INITs must come first */
     HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
 };
 
 static void hub_init_func2(struct work_struct *ws);
 static void hub_init_func3(struct work_struct *ws);
 
 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 {
     struct usb_device *hdev = hub->hdev;
     struct usb_hcd *hcd;
     int ret;
     int port1;
     int status;
     bool need_debounce_delay = false;
     unsigned delay;
 
     /* Continue a partial initialization */
     if (type == HUB_INIT2 || type == HUB_INIT3) {
         device_lock(&hdev->dev);
 
         /* Was the hub disconnected while we were waiting? */
         if (hub->disconnected)
             goto disconnected;
         if (type == HUB_INIT2)
             goto init2;
         goto init3;
     }
     kref_get(&hub->kref);
 
     /* The superspeed hub except for root hub has to use Hub Depth
      * value as an offset into the route string to locate the bits
      * it uses to determine the downstream port number. So hub driver
      * should send a set hub depth request to superspeed hub after
      * the superspeed hub is set configuration in initialization or
      * reset procedure.
      *
      * After a resume, port power should still be on.
      * For any other type of activation, turn it on.
      */
     if (type != HUB_RESUME) {
         if (hdev->parent && hub_is_superspeed(hdev)) {
             ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
                     HUB_SET_DEPTH, USB_RT_HUB,
                     hdev->level - 1, 0, NULL, 0,
                     USB_CTRL_SET_TIMEOUT);
             if (ret < 0)
                 dev_err(hub->intfdev,
                         "set hub depth failed\n");
         }
 
         /* Speed up system boot by using a delayed_work for the
          * hub's initial power-up delays.  This is pretty awkward
          * and the implementation looks like a home-brewed sort of
          * setjmp/longjmp, but it saves at least 100 ms for each
          * root hub (assuming usbcore is compiled into the kernel
          * rather than as a module).  It adds up.
          *
          * This can't be done for HUB_RESUME or HUB_RESET_RESUME
          * because for those activation types the ports have to be
          * operational when we return.  In theory this could be done
          * for HUB_POST_RESET, but it's easier not to.
          */
         if (type == HUB_INIT) {
             delay = hub_power_on_good_delay(hub);
 
             hub_power_on(hub, false);
             INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
             queue_delayed_work(system_power_efficient_wq,
                     &hub->init_work,
                     msecs_to_jiffies(delay));
 
             /* Suppress autosuspend until init is done */
             usb_autopm_get_interface_no_resume(
                     to_usb_interface(hub->intfdev));
             return;     /* Continues at init2: below */
         } else if (type == HUB_RESET_RESUME) {
             /* The internal host controller state for the hub device
              * may be gone after a host power loss on system resume.
              * Update the device's info so the HW knows it's a hub.
              */
             hcd = bus_to_hcd(hdev->bus);
             if (hcd->driver->update_hub_device) {
                 ret = hcd->driver->update_hub_device(hcd, hdev,
                         &hub->tt, GFP_NOIO);
                 if (ret < 0) {
                     dev_err(hub->intfdev,
                         "Host not accepting hub info update\n");
                     dev_err(hub->intfdev,
                         "LS/FS devices and hubs may not work under this hub\n");
                 }
             }
             hub_power_on(hub, true);
         } else {
             hub_power_on(hub, true);
         }
     /* Give some time on remote wakeup to let links to transit to U0 */
     } else if (hub_is_superspeed(hub->hdev))
         msleep(20);
 
  init2:
 
     /*
      * Check each port and set hub->change_bits to let hub_wq know
      * which ports need attention.
      */
     for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
         struct usb_port *port_dev = hub->ports[port1 - 1];
         struct usb_device *udev = port_dev->child;
         u16 portstatus, portchange;
 
         portstatus = portchange = 0;
         status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
         if (status)
             goto abort;
 
         if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
             dev_dbg(&port_dev->dev, "status %04x change %04x\n",
                     portstatus, portchange);
 
         /*
          * After anything other than HUB_RESUME (i.e., initialization
          * or any sort of reset), every port should be disabled.
          * Unconnected ports should likewise be disabled (paranoia),
          * and so should ports for which we have no usb_device.
          */
         if ((portstatus & USB_PORT_STAT_ENABLE) && (
                 type != HUB_RESUME ||
                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
                 !udev ||
                 udev->state == USB_STATE_NOTATTACHED)) {
             /*
              * USB3 protocol ports will automatically transition
              * to Enabled state when detect an USB3.0 device attach.
              * Do not disable USB3 protocol ports, just pretend
              * power was lost
              */
             portstatus &= ~USB_PORT_STAT_ENABLE;
             if (!hub_is_superspeed(hdev))
                 usb_clear_port_feature(hdev, port1,
                            USB_PORT_FEAT_ENABLE);
         }
 
         /* Make sure a warm-reset request is handled by port_event */
         if (type == HUB_RESUME &&
             hub_port_warm_reset_required(hub, port1, portstatus))
             set_bit(port1, hub->event_bits);
 
         /*
          * Add debounce if USB3 link is in polling/link training state.
          * Link will automatically transition to Enabled state after
          * link training completes.
          */
         if (hub_is_superspeed(hdev) &&
             ((portstatus & USB_PORT_STAT_LINK_STATE) ==
                         USB_SS_PORT_LS_POLLING))
             need_debounce_delay = true;
 
         /* Clear status-change flags; we'll debounce later */
         if (portchange & USB_PORT_STAT_C_CONNECTION) {
             need_debounce_delay = true;
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_CONNECTION);
         }
         if (portchange & USB_PORT_STAT_C_ENABLE) {
             need_debounce_delay = true;
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_ENABLE);
         }
         if (portchange & USB_PORT_STAT_C_RESET) {
             need_debounce_delay = true;
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_RESET);
         }
         if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
                 hub_is_superspeed(hub->hdev)) {
             need_debounce_delay = true;
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_BH_PORT_RESET);
         }
         /* We can forget about a "removed" device when there's a
          * physical disconnect or the connect status changes.
          */
         if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
                 (portchange & USB_PORT_STAT_C_CONNECTION))
             clear_bit(port1, hub->removed_bits);
 
         if (!udev || udev->state == USB_STATE_NOTATTACHED) {
             /* Tell hub_wq to disconnect the device or
              * check for a new connection or over current condition.
              * Based on USB2.0 Spec Section 11.12.5,
              * C_PORT_OVER_CURRENT could be set while
              * PORT_OVER_CURRENT is not. So check for any of them.
              */
             if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
                 (portchange & USB_PORT_STAT_C_CONNECTION) ||
                 (portstatus & USB_PORT_STAT_OVERCURRENT) ||
                 (portchange & USB_PORT_STAT_C_OVERCURRENT))
                 set_bit(port1, hub->change_bits);
 
         } else if (portstatus & USB_PORT_STAT_ENABLE) {
             bool port_resumed = (portstatus &
                     USB_PORT_STAT_LINK_STATE) ==
                 USB_SS_PORT_LS_U0;
             /* The power session apparently survived the resume.
              * If there was an overcurrent or suspend change
              * (i.e., remote wakeup request), have hub_wq
              * take care of it.  Look at the port link state
              * for USB 3.0 hubs, since they don't have a suspend
              * change bit, and they don't set the port link change
              * bit on device-initiated resume.
              */
             if (portchange || (hub_is_superspeed(hub->hdev) &&
                         port_resumed))
                 set_bit(port1, hub->event_bits);
 
         } else if (udev->persist_enabled) {
 #ifdef CONFIG_PM
             udev->reset_resume = 1;
 #endif
             /* Don't set the change_bits when the device
              * was powered off.
              */
             if (test_bit(port1, hub->power_bits))
                 set_bit(port1, hub->change_bits);
 
         } else {
             /* The power session is gone; tell hub_wq */
             usb_set_device_state(udev, USB_STATE_NOTATTACHED);
             set_bit(port1, hub->change_bits);
         }
     }
 
     /* If no port-status-change flags were set, we don't need any
      * debouncing.  If flags were set we can try to debounce the
      * ports all at once right now, instead of letting hub_wq do them
      * one at a time later on.
      *
      * If any port-status changes do occur during this delay, hub_wq
      * will see them later and handle them normally.
      */
     if (need_debounce_delay) {
         delay = HUB_DEBOUNCE_STABLE;
 
         /* Don't do a long sleep inside a workqueue routine */
         if (type == HUB_INIT2) {
             INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
             queue_delayed_work(system_power_efficient_wq,
                     &hub->init_work,
                     msecs_to_jiffies(delay));
             device_unlock(&hdev->dev);
             return;     /* Continues at init3: below */
         } else {
             msleep(delay);
         }
     }
  init3:
     hub->quiescing = 0;
 
     status = usb_submit_urb(hub->urb, GFP_NOIO);
     if (status < 0)
         dev_err(hub->intfdev, "activate --> %d\n", status);
     if (hub->has_indicators && blinkenlights)
         queue_delayed_work(system_power_efficient_wq,
                 &hub->leds, LED_CYCLE_PERIOD);
 
     /* Scan all ports that need attention */
     kick_hub_wq(hub);
  abort:
     if (type == HUB_INIT2 || type == HUB_INIT3) {
         /* Allow autosuspend if it was suppressed */
  disconnected:
         usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
         device_unlock(&hdev->dev);
     }
 
     kref_put(&hub->kref, hub_release);
 }
 
 /* Implement the continuations for the delays above */
 static void hub_init_func2(struct work_struct *ws)
 {
     struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 
     hub_activate(hub, HUB_INIT2);
 }
 
 static void hub_init_func3(struct work_struct *ws)
 {
     struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
 
     hub_activate(hub, HUB_INIT3);
 }
 
 enum hub_quiescing_type {
     HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
 };
 
 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
 {
     struct usb_device *hdev = hub->hdev;
     unsigned long flags;
     int i;
 
     /* hub_wq and related activity won't re-trigger */
     spin_lock_irqsave(&hub->irq_urb_lock, flags);
     hub->quiescing = 1;
     spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 
     if (type != HUB_SUSPEND) {
         /* Disconnect all the children */
         for (i = 0; i < hdev->maxchild; ++i) {
             if (hub->ports[i]->child)
                 usb_disconnect(&hub->ports[i]->child);
         }
     }
 
     /* Stop hub_wq and related activity */
     del_timer_sync(&hub->irq_urb_retry);
     usb_kill_urb(hub->urb);
     if (hub->has_indicators)
         cancel_delayed_work_sync(&hub->leds);
     if (hub->tt.hub)
         flush_work(&hub->tt.clear_work);
 }
 
 static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
 {
     int i;
 
     for (i = 0; i < hub->hdev->maxchild; ++i)
         pm_runtime_barrier(&hub->ports[i]->dev);
 }
 
 /* caller has locked the hub device */
 static int hub_pre_reset(struct usb_interface *intf)
 {
     struct usb_hub *hub = usb_get_intfdata(intf);
 
     hub_quiesce(hub, HUB_PRE_RESET);
     hub->in_reset = 1;
     hub_pm_barrier_for_all_ports(hub);
     return 0;
 }
 
 /* caller has locked the hub device */
 static int hub_post_reset(struct usb_interface *intf)
 {
     struct usb_hub *hub = usb_get_intfdata(intf);
 
     hub->in_reset = 0;
     hub_pm_barrier_for_all_ports(hub);
     hub_activate(hub, HUB_POST_RESET);
     return 0;
 }
 
 static int hub_configure(struct usb_hub *hub,
     struct usb_endpoint_descriptor *endpoint)
 {
     struct usb_hcd *hcd;
     struct usb_device *hdev = hub->hdev;
     struct device *hub_dev = hub->intfdev;
     u16 hubstatus, hubchange;
     u16 wHubCharacteristics;
     unsigned int pipe;
     int maxp, ret, i;
     char *message = "out of memory";
     unsigned unit_load;
     unsigned full_load;
     unsigned maxchild;
 
     hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
     if (!hub->buffer) {
         ret = -ENOMEM;
         goto fail;
     }
 
     hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
     if (!hub->status) {
         ret = -ENOMEM;
         goto fail;
     }
     mutex_init(&hub->status_mutex);
 
     hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
     if (!hub->descriptor) {
         ret = -ENOMEM;
         goto fail;
     }
 
     /* Request the entire hub descriptor.
      * hub->descriptor can handle USB_MAXCHILDREN ports,
      * but a (non-SS) hub can/will return fewer bytes here.
      */
     ret = get_hub_descriptor(hdev, hub->descriptor);
     if (ret < 0) {
         message = "can't read hub descriptor";
         goto fail;
     }
 
     maxchild = USB_MAXCHILDREN;
     if (hub_is_superspeed(hdev))
         maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
 
     if (hub->descriptor->bNbrPorts > maxchild) {
         message = "hub has too many ports!";
         ret = -ENODEV;
         goto fail;
     } else if (hub->descriptor->bNbrPorts == 0) {
         message = "hub doesn't have any ports!";
         ret = -ENODEV;
         goto fail;
     }
 
     /*
      * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
      * The resulting value will be used for SetIsochDelay() request.
      */
     if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
         u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
 
         if (hdev->parent)
             delay += hdev->parent->hub_delay;
 
         delay += USB_TP_TRANSMISSION_DELAY;
         hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
     }
 
     maxchild = hub->descriptor->bNbrPorts;
     dev_info(hub_dev, "%d port%s detected\n", maxchild,
             (maxchild == 1) ? "" : "s");
 
     hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
     if (!hub->ports) {
         ret = -ENOMEM;
         goto fail;
     }
 
     wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
     if (hub_is_superspeed(hdev)) {
         unit_load = 150;
         full_load = 900;
     } else {
         unit_load = 100;
         full_load = 500;
     }
 
     /* FIXME for USB 3.0, skip for now */
     if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
             !(hub_is_superspeed(hdev))) {
         char    portstr[USB_MAXCHILDREN + 1];
 
         for (i = 0; i < maxchild; i++)
             portstr[i] = hub->descriptor->u.hs.DeviceRemovable
                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
                 ? 'F' : 'R';
         portstr[maxchild] = 0;
         dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
     } else
         dev_dbg(hub_dev, "standalone hub\n");
 
     switch (wHubCharacteristics & HUB_CHAR_LPSM) {
     case HUB_CHAR_COMMON_LPSM:
         dev_dbg(hub_dev, "ganged power switching\n");
         break;
     case HUB_CHAR_INDV_PORT_LPSM:
         dev_dbg(hub_dev, "individual port power switching\n");
         break;
     case HUB_CHAR_NO_LPSM:
     case HUB_CHAR_LPSM:
         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
         break;
     }
 
     switch (wHubCharacteristics & HUB_CHAR_OCPM) {
     case HUB_CHAR_COMMON_OCPM:
         dev_dbg(hub_dev, "global over-current protection\n");
         break;
     case HUB_CHAR_INDV_PORT_OCPM:
         dev_dbg(hub_dev, "individual port over-current protection\n");
         break;
     case HUB_CHAR_NO_OCPM:
     case HUB_CHAR_OCPM:
         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.clear_work, hub_tt_work);
     switch (hdev->descriptor.bDeviceProtocol) {
     case USB_HUB_PR_FS:
         break;
     case USB_HUB_PR_HS_SINGLE_TT:
         dev_dbg(hub_dev, "Single TT\n");
         hub->tt.hub = hdev;
         break;
     case USB_HUB_PR_HS_MULTI_TT:
         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;
     case USB_HUB_PR_SS:
         /* USB 3.0 hubs don't have a TT */
         break;
     default:
         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
             hdev->descriptor.bDeviceProtocol);
         break;
     }
 
     /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
     switch (wHubCharacteristics & HUB_CHAR_TTTT) {
     case HUB_TTTT_8_BITS:
         if (hdev->descriptor.bDeviceProtocol != 0) {
             hub->tt.think_time = 666;
             dev_dbg(hub_dev, "TT requires at most %d "
                     "FS bit times (%d ns)\n",
                 8, hub->tt.think_time);
         }
         break;
     case HUB_TTTT_16_BITS:
         hub->tt.think_time = 666 * 2;
         dev_dbg(hub_dev, "TT requires at most %d "
                 "FS bit times (%d ns)\n",
             16, hub->tt.think_time);
         break;
     case HUB_TTTT_24_BITS:
         hub->tt.think_time = 666 * 3;
         dev_dbg(hub_dev, "TT requires at most %d "
                 "FS bit times (%d ns)\n",
             24, hub->tt.think_time);
         break;
     case HUB_TTTT_32_BITS:
         hub->tt.think_time = 666 * 4;
         dev_dbg(hub_dev, "TT requires at most %d "
                 "FS bit times (%d ns)\n",
             32, hub->tt.think_time);
         break;
     }
 
     /* probe() zeroes hub->indicator[] */
     if (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_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
     if (ret) {
         message = "can't get hub status";
         goto fail;
     }
     hcd = bus_to_hcd(hdev->bus);
     if (hdev == hdev->bus->root_hub) {
         if (hcd->power_budget > 0)
             hdev->bus_mA = hcd->power_budget;
         else
             hdev->bus_mA = full_load * maxchild;
         if (hdev->bus_mA >= full_load)
             hub->mA_per_port = full_load;
         else {
             hub->mA_per_port = hdev->bus_mA;
             hub->limited_power = 1;
         }
     } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
         int remaining = hdev->bus_mA -
             hub->descriptor->bHubContrCurrent;
 
         dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
             hub->descriptor->bHubContrCurrent);
         hub->limited_power = 1;
 
         if (remaining < maxchild * unit_load)
             dev_warn(hub_dev,
                     "insufficient power available "
                     "to use all downstream ports\n");
         hub->mA_per_port = unit_load;   /* 7.2.1 */
 
     } else {    /* Self-powered external hub */
         /* FIXME: What about battery-powered external hubs that
          * provide less current per port? */
         hub->mA_per_port = full_load;
     }
     if (hub->mA_per_port < full_load)
         dev_dbg(hub_dev, "%umA bus power budget for each child\n",
                 hub->mA_per_port);
 
     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 ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
         dev_dbg(hub_dev, "%sover-current condition exists\n",
             (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 
     /* set up the interrupt endpoint
      * We use the EP's maxpacket size instead of (PORTS+1+7)/8
      * bytes as USB2.0[11.12.3] says because some hubs are known
      * to send more data (and thus cause overflow). For root hubs,
      * maxpktsize is defined in hcd.c's fake endpoint descriptors
      * to be big enough for at least USB_MAXCHILDREN ports. */
     pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
     maxp = usb_maxpacket(hdev, pipe);
 
     if (maxp > sizeof(*hub->buffer))
         maxp = sizeof(*hub->buffer);
 
     hub->urb = usb_alloc_urb(0, GFP_KERNEL);
     if (!hub->urb) {
         ret = -ENOMEM;
         goto fail;
     }
 
     usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
         hub, endpoint->bInterval);
 
     /* maybe cycle the hub leds */
     if (hub->has_indicators && blinkenlights)
         hub->indicator[0] = INDICATOR_CYCLE;
 
     mutex_lock(&usb_port_peer_mutex);
     for (i = 0; i < maxchild; i++) {
         ret = usb_hub_create_port_device(hub, i + 1);
         if (ret < 0) {
             dev_err(hub->intfdev,
                 "couldn't create port%d device.\n", i + 1);
             break;
         }
     }
     hdev->maxchild = i;
     for (i = 0; i < hdev->maxchild; i++) {
         struct usb_port *port_dev = hub->ports[i];
 
         pm_runtime_put(&port_dev->dev);
     }
 
     mutex_unlock(&usb_port_peer_mutex);
     if (ret < 0)
         goto fail;
 
     /* Update the HCD's internal representation of this hub before hub_wq
      * starts getting port status changes for devices under the hub.
      */
     if (hcd->driver->update_hub_device) {
         ret = hcd->driver->update_hub_device(hcd, hdev,
                 &hub->tt, GFP_KERNEL);
         if (ret < 0) {
             message = "can't update HCD hub info";
             goto fail;
         }
     }
 
     usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
 
     hub_activate(hub, HUB_INIT);
     return 0;
 
 fail:
     dev_err(hub_dev, "config failed, %s (err %d)\n",
             message, ret);
     /* hub_disconnect() frees urb and descriptor */
     return ret;
 }
 
 static void hub_release(struct kref *kref)
 {
     struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
 
     usb_put_dev(hub->hdev);
     usb_put_intf(to_usb_interface(hub->intfdev));
     kfree(hub);
 }
 
 static unsigned highspeed_hubs;
 
 static void hub_disconnect(struct usb_interface *intf)
 {
     struct usb_hub *hub = usb_get_intfdata(intf);
     struct usb_device *hdev = interface_to_usbdev(intf);
     int port1;
 
     /*
      * Stop adding new hub events. We do not want to block here and thus
      * will not try to remove any pending work item.
      */
     hub->disconnected = 1;
 
     /* Disconnect all children and quiesce the hub */
     hub->error = 0;
     hub_quiesce(hub, HUB_DISCONNECT);
 
     mutex_lock(&usb_port_peer_mutex);
 
     /* Avoid races with recursively_mark_NOTATTACHED() */
     spin_lock_irq(&device_state_lock);
     port1 = hdev->maxchild;
     hdev->maxchild = 0;
     usb_set_intfdata(intf, NULL);
     spin_unlock_irq(&device_state_lock);
 
     for (; port1 > 0; --port1)
         usb_hub_remove_port_device(hub, port1);
 
     mutex_unlock(&usb_port_peer_mutex);
 
     if (hub->hdev->speed == USB_SPEED_HIGH)
         highspeed_hubs--;
 
     usb_free_urb(hub->urb);
     kfree(hub->ports);
     kfree(hub->descriptor);
     kfree(hub->status);
     kfree(hub->buffer);
 
     pm_suspend_ignore_children(&intf->dev, false);
 
     if (hub->quirk_disable_autosuspend)
         usb_autopm_put_interface(intf);
 
     onboard_hub_destroy_pdevs(&hub->onboard_hub_devs);
 
     kref_put(&hub->kref, hub_release);
 }
 
 static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
 {
     /* 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)
         return false;
 
     /* Multiple endpoints? What kind of mutant ninja-hub is this? */
     if (desc->desc.bNumEndpoints != 1)
         return false;
 
     /* If the first endpoint is not interrupt IN, we'd better punt! */
     if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
         return false;
 
         return true;
 }
 
 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
     struct usb_host_interface *desc;
     struct usb_device *hdev;
     struct usb_hub *hub;
 
     desc = intf->cur_altsetting;
     hdev = interface_to_usbdev(intf);
 
     /*
      * Set default autosuspend delay as 0 to speedup bus suspend,
      * based on the below considerations:
      *
      * - Unlike other drivers, the hub driver does not rely on the
      *   autosuspend delay to provide enough time to handle a wakeup
      *   event, and the submitted status URB is just to check future
      *   change on hub downstream ports, so it is safe to do it.
      *
      * - The patch might cause one or more auto supend/resume for
      *   below very rare devices when they are plugged into hub
      *   first time:
      *
      *      devices having trouble initializing, and disconnect
      *      themselves from the bus and then reconnect a second
      *      or so later
      *
      *      devices just for downloading firmware, and disconnects
      *      themselves after completing it
      *
      *   For these quite rare devices, their drivers may change the
      *   autosuspend delay of their parent hub in the probe() to one
      *   appropriate value to avoid the subtle problem if someone
      *   does care it.
      *
      * - The patch may cause one or more auto suspend/resume on
      *   hub during running 'lsusb', but it is probably too
      *   infrequent to worry about.
      *
      * - Change autosuspend delay of hub can avoid unnecessary auto
      *   suspend timer for hub, also may decrease power consumption
      *   of USB bus.
      *
      * - If user has indicated to prevent autosuspend by passing
      *   usbcore.autosuspend = -1 then keep autosuspend disabled.
      */
 #ifdef CONFIG_PM
     if (hdev->dev.power.autosuspend_delay >= 0)
         pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
 #endif
 
     /*
      * Hubs have proper suspend/resume support, except for root hubs
      * where the controller driver doesn't have bus_suspend and
      * bus_resume methods.
      */
     if (hdev->parent) {     /* normal device */
         usb_enable_autosuspend(hdev);
     } else {            /* root hub */
         const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
 
         if (drv->bus_suspend && drv->bus_resume)
             usb_enable_autosuspend(hdev);
     }
 
     if (hdev->level == MAX_TOPO_LEVEL) {
         dev_err(&intf->dev,
             "Unsupported bus topology: hub nested too deep\n");
         return -E2BIG;
     }
 
 #ifdef  CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
     if (hdev->parent) {
         dev_warn(&intf->dev, "ignoring external hub\n");
         return -ENODEV;
     }
 #endif
 
     if (!hub_descriptor_is_sane(desc)) {
         dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
         return -EIO;
     }
 
     /* We found a hub */
     dev_info(&intf->dev, "USB hub found\n");
 
     hub = kzalloc(sizeof(*hub), GFP_KERNEL);
     if (!hub)
         return -ENOMEM;
 
     kref_init(&hub->kref);
     hub->intfdev = &intf->dev;
     hub->hdev = hdev;
     INIT_DELAYED_WORK(&hub->leds, led_work);
     INIT_DELAYED_WORK(&hub->init_work, NULL);
     INIT_WORK(&hub->events, hub_event);
     INIT_LIST_HEAD(&hub->onboard_hub_devs);
     spin_lock_init(&hub->irq_urb_lock);
     timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
     usb_get_intf(intf);
     usb_get_dev(hdev);
 
     usb_set_intfdata(intf, hub);
     intf->needs_remote_wakeup = 1;
     pm_suspend_ignore_children(&intf->dev, true);
 
     if (hdev->speed == USB_SPEED_HIGH)
         highspeed_hubs++;
 
     if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
         hub->quirk_check_port_auto_suspend = 1;
 
     if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
         hub->quirk_disable_autosuspend = 1;
         usb_autopm_get_interface_no_resume(intf);
     }
 
     if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) {
         onboard_hub_create_pdevs(hdev, &hub->onboard_hub_devs);
 
         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);
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 
     /* 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 (hub->ports[i]->child == NULL)
                     info->port[i] = 0;
                 else
                     info->port[i] =
                         hub->ports[i]->child->devnum;
             }
         }
         spin_unlock_irq(&device_state_lock);
 
         return info->nports + 1;
         }
 
     default:
         return -ENOSYS;
     }
 }
 
 /*
  * Allow user programs to claim ports on a hub.  When a device is attached
  * to one of these "claimed" ports, the program will "own" the device.
  */
 static int find_port_owner(struct usb_device *hdev, unsigned port1,
         struct usb_dev_state ***ppowner)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 
     if (hdev->state == USB_STATE_NOTATTACHED)
         return -ENODEV;
     if (port1 == 0 || port1 > hdev->maxchild)
         return -EINVAL;
 
     /* Devices not managed by the hub driver
      * will always have maxchild equal to 0.
      */
     *ppowner = &(hub->ports[port1 - 1]->port_owner);
     return 0;
 }
 
 /* In the following three functions, the caller must hold hdev's lock */
 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
                struct usb_dev_state *owner)
 {
     int rc;
     struct usb_dev_state **powner;
 
     rc = find_port_owner(hdev, port1, &powner);
     if (rc)
         return rc;
     if (*powner)
         return -EBUSY;
     *powner = owner;
     return rc;
 }
 EXPORT_SYMBOL_GPL(usb_hub_claim_port);
 
 int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
              struct usb_dev_state *owner)
 {
     int rc;
     struct usb_dev_state **powner;
 
     rc = find_port_owner(hdev, port1, &powner);
     if (rc)
         return rc;
     if (*powner != owner)
         return -ENOENT;
     *powner = NULL;
     return rc;
 }
 EXPORT_SYMBOL_GPL(usb_hub_release_port);
 
 void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
     int n;
 
     for (n = 0; n < hdev->maxchild; n++) {
         if (hub->ports[n]->port_owner == owner)
             hub->ports[n]->port_owner = NULL;
     }
 
 }
 
 /* The caller must hold udev's lock */
 bool usb_device_is_owned(struct usb_device *udev)
 {
     struct usb_hub *hub;
 
     if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
         return false;
     hub = usb_hub_to_struct_hub(udev->parent);
     return !!hub->ports[udev->portnum - 1]->port_owner;
 }
 
 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(udev);
     int i;
 
     for (i = 0; i < udev->maxchild; ++i) {
         if (hub->ports[i]->child)
             recursively_mark_NOTATTACHED(hub->ports[i]->child);
     }
     if (udev->state == USB_STATE_SUSPENDED)
         udev->active_duration -= jiffies;
     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;
     int wakeup = -1;
 
     spin_lock_irqsave(&device_state_lock, flags);
     if (udev->state == USB_STATE_NOTATTACHED)
         ;   /* do nothing */
     else if (new_state != USB_STATE_NOTATTACHED) {
 
         /* root hub wakeup capabilities are managed out-of-band
          * and may involve silicon errata ... ignore them here.
          */
         if (udev->parent) {
             if (udev->state == USB_STATE_SUSPENDED
                     || new_state == USB_STATE_SUSPENDED)
                 ;   /* No change to wakeup settings */
             else if (new_state == USB_STATE_CONFIGURED)
                 wakeup = (udev->quirks &
                     USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
                     udev->actconfig->desc.bmAttributes &
                     USB_CONFIG_ATT_WAKEUP;
             else
                 wakeup = 0;
         }
         if (udev->state == USB_STATE_SUSPENDED &&
             new_state != USB_STATE_SUSPENDED)
             udev->active_duration -= jiffies;
         else if (new_state == USB_STATE_SUSPENDED &&
                 udev->state != USB_STATE_SUSPENDED)
             udev->active_duration += jiffies;
         udev->state = new_state;
     } else
         recursively_mark_NOTATTACHED(udev);
     spin_unlock_irqrestore(&device_state_lock, flags);
     if (wakeup >= 0)
         device_set_wakeup_capable(&udev->dev, wakeup);
 }
 EXPORT_SYMBOL_GPL(usb_set_device_state);
 
 /*
  * Choose a device number.
  *
  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
  * USB-2.0 buses they are also used as device addresses, however on
  * USB-3.0 buses the address is assigned by the controller hardware
  * and it usually is not the same as the device number.
  *
  * WUSB devices are simple: they have no hubs behind, so the mapping
  * device <-> virtual port number becomes 1:1. Why? to simplify the
  * life of the device connection logic in
  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
  * handshake we need to assign a temporary address in the unauthorized
  * space. For simplicity we use the first virtual port number found to
  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
  * and that becomes it's address [X < 128] or its unauthorized address
  * [X | 0x80].
  *
  * We add 1 as an offset to the one-based USB-stack port number
  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
  * 0 is reserved by USB for default address; (b) Linux's USB stack
  * uses always #1 for the root hub of the controller. So USB stack's
  * port #1, which is wusb virtual-port #0 has address #2.
  *
  * Devices connected under xHCI are not as simple.  The host controller
  * supports virtualization, so the hardware assigns device addresses and
  * the HCD must setup data structures before issuing a set address
  * command to the hardware.
  */
 static void choose_devnum(struct usb_device *udev)
 {
     int     devnum;
     struct usb_bus  *bus = udev->bus;
 
     /* be safe when more hub events are proceed in parallel */
     mutex_lock(&bus->devnum_next_mutex);
     if (udev->wusb) {
         devnum = udev->portnum + 1;
         BUG_ON(test_bit(devnum, bus->devmap.devicemap));
     } else {
         /* 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;
     }
     mutex_unlock(&bus->devnum_next_mutex);
 }
 
 static void release_devnum(struct usb_device *udev)
 {
     if (udev->devnum > 0) {
         clear_bit(udev->devnum, udev->bus->devmap.devicemap);
         udev->devnum = -1;
     }
 }
 
 static void update_devnum(struct usb_device *udev, int devnum)
 {
     /* The address for a WUSB device is managed by wusbcore. */
     if (!udev->wusb)
         udev->devnum = devnum;
     if (!udev->devaddr)
         udev->devaddr = (u8)devnum;
 }
 
 static void hub_free_dev(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     /* Root hubs aren't real devices, so don't free HCD resources */
     if (hcd->driver->free_dev && udev->parent)
         hcd->driver->free_dev(hcd, udev);
 }
 
 static void hub_disconnect_children(struct usb_device *udev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(udev);
     int i;
 
     /* Free up all the children before we remove this device */
     for (i = 0; i < udev->maxchild; i++) {
         if (hub->ports[i]->child)
             usb_disconnect(&hub->ports[i]->child);
     }
 }
 
 /**
  * usb_disconnect - disconnect a device (usbcore-internal)
  * @pdev: pointer to device being disconnected
  *
  * Context: task context, might sleep
  *
  * 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 the caller must hold the usb_bus_idr_lock,
  * which protects the set of root hubs as well as the list of buses.
  *
  * 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_port *port_dev = NULL;
     struct usb_device *udev = *pdev;
     struct usb_hub *hub = NULL;
     int port1 = 1;
 
     /* mark the device as inactive, so any further urb submissions for
      * this device (and any of its children) will fail immediately.
      * this quiesces everything except pending urbs.
      */
     usb_set_device_state(udev, USB_STATE_NOTATTACHED);
     dev_info(&udev->dev, "USB disconnect, device number %d\n",
             udev->devnum);
 
     /*
      * Ensure that the pm runtime code knows that the USB device
      * is in the process of being disconnected.
      */
     pm_runtime_barrier(&udev->dev);
 
     usb_lock_device(udev);
 
     hub_disconnect_children(udev);
 
     /* 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.
      */
     dev_dbg(&udev->dev, "unregistering device\n");
     usb_disable_device(udev, 0);
     usb_hcd_synchronize_unlinks(udev);
 
     if (udev->parent) {
         port1 = udev->portnum;
         hub = usb_hub_to_struct_hub(udev->parent);
         port_dev = hub->ports[port1 - 1];
 
         sysfs_remove_link(&udev->dev.kobj, "port");
         sysfs_remove_link(&port_dev->dev.kobj, "device");
 
         /*
          * As usb_port_runtime_resume() de-references udev, make
          * sure no resumes occur during removal
          */
         if (!test_and_set_bit(port1, hub->child_usage_bits))
             pm_runtime_get_sync(&port_dev->dev);
     }
 
     usb_remove_ep_devs(&udev->ep0);
     usb_unlock_device(udev);
 
     /* Unregister the device.  The device driver is responsible
      * for de-configuring the device and invoking the remove-device
      * notifier chain (used by usbfs and possibly others).
      */
     device_del(&udev->dev);
 
     /* Free the device number and delete the parent's children[]
      * (or root_hub) pointer.
      */
     release_devnum(udev);
 
     /* Avoid races with recursively_mark_NOTATTACHED() */
     spin_lock_irq(&device_state_lock);
     *pdev = NULL;
     spin_unlock_irq(&device_state_lock);
 
     if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
         pm_runtime_put(&port_dev->dev);
 
     hub_free_dev(udev);
 
     put_device(&udev->dev);
 }
 
 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
 static void show_string(struct usb_device *udev, char *id, char *string)
 {
     if (!string)
         return;
     dev_info(&udev->dev, "%s: %s\n", id, string);
 }
 
 static void announce_device(struct usb_device *udev)
 {
     u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
 
     dev_info(&udev->dev,
         "New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
         le16_to_cpu(udev->descriptor.idVendor),
         le16_to_cpu(udev->descriptor.idProduct),
         bcdDevice >> 8, bcdDevice & 0xff);
     dev_info(&udev->dev,
         "New USB 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);
 }
 #else
 static inline void announce_device(struct usb_device *udev) { }
 #endif
 
 
 /**
  * usb_enumerate_device_otg - FIXME (usbcore-internal)
  * @udev: newly addressed device (in ADDRESS state)
  *
  * Finish enumeration for On-The-Go devices
  *
  * Return: 0 if successful. A negative error code otherwise.
  */
 static int usb_enumerate_device_otg(struct usb_device *udev)
 {
     int err = 0;
 
 #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 = NULL;
         struct usb_bus          *bus = udev->bus;
         unsigned            port1 = udev->portnum;
 
         /* descriptor may appear anywhere in config */
         err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
                 le16_to_cpu(udev->config[0].desc.wTotalLength),
                 USB_DT_OTG, (void **) &desc, sizeof(*desc));
         if (err || !(desc->bmAttributes & USB_OTG_HNP))
             return 0;
 
         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,
                 USB_DEVICE_B_HNP_ENABLE,
                 0, NULL, 0,
                 USB_CTRL_SET_TIMEOUT);
             if (err < 0) {
                 /*
                  * OTG MESSAGE: report errors here,
                  * customize to match your product.
                  */
                 dev_err(&udev->dev, "can't set HNP mode: %d\n",
                                     err);
                 bus->b_hnp_enable = 0;
             }
         } else if (desc->bLength == sizeof
                 (struct usb_otg_descriptor)) {
             /* Set a_alt_hnp_support for legacy otg device */
             err = usb_control_msg(udev,
                 usb_sndctrlpipe(udev, 0),
                 USB_REQ_SET_FEATURE, 0,
                 USB_DEVICE_A_ALT_HNP_SUPPORT,
                 0, NULL, 0,
                 USB_CTRL_SET_TIMEOUT);
             if (err < 0)
                 dev_err(&udev->dev,
                     "set a_alt_hnp_support failed: %d\n",
                     err);
         }
     }
 #endif
     return err;
 }
 
 
 /**
  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
  * @udev: newly addressed device (in ADDRESS state)
  *
  * This is only called by usb_new_device() and usb_authorize_device()
  * and FIXME -- all comments that apply to them apply here wrt to
  * environment.
  *
  * If the device is WUSB and not authorized, we don't attempt to read
  * the string descriptors, as they will be errored out by the device
  * until it has been authorized.
  *
  * Return: 0 if successful. A negative error code otherwise.
  */
 static int usb_enumerate_device(struct usb_device *udev)
 {
     int err;
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     if (udev->config == NULL) {
         err = usb_get_configuration(udev);
         if (err < 0) {
             if (err != -ENODEV)
                 dev_err(&udev->dev, "can't read configurations, error %d\n",
                         err);
             return err;
         }
     }
 
     /* read the standard strings and cache them if present */
     udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
     udev->manufacturer = usb_cache_string(udev,
                           udev->descriptor.iManufacturer);
     udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
 
     err = usb_enumerate_device_otg(udev);
     if (err < 0)
         return err;
 
     if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
         !is_targeted(udev)) {
         /* Maybe it can talk to us, though we can't talk to it.
          * (Includes HNP test device.)
          */
         if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
             || udev->bus->is_b_host)) {
             err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
             if (err < 0)
                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
         }
         return -ENOTSUPP;
     }
 
     usb_detect_interface_quirks(udev);
 
     return 0;
 }
 
 static void set_usb_port_removable(struct usb_device *udev)
 {
     struct usb_device *hdev = udev->parent;
     struct usb_hub *hub;
     u8 port = udev->portnum;
     u16 wHubCharacteristics;
     bool removable = true;
 
     dev_set_removable(&udev->dev, DEVICE_REMOVABLE_UNKNOWN);
 
     if (!hdev)
         return;
 
     hub = usb_hub_to_struct_hub(udev->parent);
 
     /*
      * If the platform firmware has provided information about a port,
      * use that to determine whether it's removable.
      */
     switch (hub->ports[udev->portnum - 1]->connect_type) {
     case USB_PORT_CONNECT_TYPE_HOT_PLUG:
         dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
         return;
     case USB_PORT_CONNECT_TYPE_HARD_WIRED:
     case USB_PORT_NOT_USED:
         dev_set_removable(&udev->dev, DEVICE_FIXED);
         return;
     default:
         break;
     }
 
     /*
      * Otherwise, check whether the hub knows whether a port is removable
      * or not
      */
     wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 
     if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
         return;
 
     if (hub_is_superspeed(hdev)) {
         if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
                 & (1 << port))
             removable = false;
     } else {
         if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
             removable = false;
     }
 
     if (removable)
         dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
     else
         dev_set_removable(&udev->dev, DEVICE_FIXED);
 
 }
 
 /**
  * usb_new_device - perform initial device setup (usbcore-internal)
  * @udev: newly addressed device (in ADDRESS state)
  *
  * This is called with devices which have been detected but not fully
  * enumerated.  The device descriptor is available, but not descriptors
  * for any device configuration.  The caller must have locked either
  * the parent hub (if udev is a normal device) or else the
  * usb_bus_idr_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.
  *
  * This call is synchronous, and may not be used in an interrupt context.
  *
  * Only the hub driver or root-hub registrar should ever call this.
  *
  * Return: Whether the device is configured properly or not. Zero if the
  * interface was registered with the driver core; else a negative errno
  * value.
  *
  */
 int usb_new_device(struct usb_device *udev)
 {
     int err;
 
     if (udev->parent) {
         /* Initialize non-root-hub device wakeup to disabled;
          * device (un)configuration controls wakeup capable
          * sysfs power/wakeup controls wakeup enabled/disabled
          */
         device_init_wakeup(&udev->dev, 0);
     }
 
     /* Tell the runtime-PM framework the device is active */
     pm_runtime_set_active(&udev->dev);
     pm_runtime_get_noresume(&udev->dev);
     pm_runtime_use_autosuspend(&udev->dev);
     pm_runtime_enable(&udev->dev);
 
     /* By default, forbid autosuspend for all devices.  It will be
      * allowed for hubs during binding.
      */
     usb_disable_autosuspend(udev);
 
     err = usb_enumerate_device(udev);   /* Read descriptors */
     if (err < 0)
         goto fail;
     dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
             udev->devnum, udev->bus->busnum,
             (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
     /* export the usbdev device-node for libusb */
     udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
             (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
 
     /* Tell the world! */
     announce_device(udev);
 
     if (udev->serial)
         add_device_randomness(udev->serial, strlen(udev->serial));
     if (udev->product)
         add_device_randomness(udev->product, strlen(udev->product));
     if (udev->manufacturer)
         add_device_randomness(udev->manufacturer,
                       strlen(udev->manufacturer));
 
     device_enable_async_suspend(&udev->dev);
 
     /* check whether the hub or firmware marks this port as non-removable */
     set_usb_port_removable(udev);
 
     /* Register the device.  The device driver is responsible
      * for configuring the device and invoking the add-device
      * notifier chain (used by usbfs and possibly others).
      */
     err = device_add(&udev->dev);
     if (err) {
         dev_err(&udev->dev, "can't device_add, error %d\n", err);
         goto fail;
     }
 
     /* Create link files between child device and usb port device. */
     if (udev->parent) {
         struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
         int port1 = udev->portnum;
         struct usb_port *port_dev = hub->ports[port1 - 1];
 
         err = sysfs_create_link(&udev->dev.kobj,
                 &port_dev->dev.kobj, "port");
         if (err)
             goto fail;
 
         err = sysfs_create_link(&port_dev->dev.kobj,
                 &udev->dev.kobj, "device");
         if (err) {
             sysfs_remove_link(&udev->dev.kobj, "port");
             goto fail;
         }
 
         if (!test_and_set_bit(port1, hub->child_usage_bits))
             pm_runtime_get_sync(&port_dev->dev);
     }
 
     (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
     usb_mark_last_busy(udev);
     pm_runtime_put_sync_autosuspend(&udev->dev);
     return err;
 
 fail:
     usb_set_device_state(udev, USB_STATE_NOTATTACHED);
     pm_runtime_disable(&udev->dev);
     pm_runtime_set_suspended(&udev->dev);
     return err;
 }
 
 
 /**
  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
  * @usb_dev: USB device
  *
  * Move the USB device to a very basic state where interfaces are disabled
  * and the device is in fact unconfigured and unusable.
  *
  * We share a lock (that we have) with device_del(), so we need to
  * defer its call.
  *
  * Return: 0.
  */
 int usb_deauthorize_device(struct usb_device *usb_dev)
 {
     usb_lock_device(usb_dev);
     if (usb_dev->authorized == 0)
         goto out_unauthorized;
 
     usb_dev->authorized = 0;
     usb_set_configuration(usb_dev, -1);
 
 out_unauthorized:
     usb_unlock_device(usb_dev);
     return 0;
 }
 
 
 int usb_authorize_device(struct usb_device *usb_dev)
 {
     int result = 0, c;
 
     usb_lock_device(usb_dev);
     if (usb_dev->authorized == 1)
         goto out_authorized;
 
     result = usb_autoresume_device(usb_dev);
     if (result < 0) {
         dev_err(&usb_dev->dev,
             "can't autoresume for authorization: %d\n", result);
         goto error_autoresume;
     }
 
     if (usb_dev->wusb) {
         result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
         if (result < 0) {
             dev_err(&usb_dev->dev, "can't re-read device descriptor for "
                 "authorization: %d\n", result);
             goto error_device_descriptor;
         }
     }
 
     usb_dev->authorized = 1;
     /* Choose and set the configuration.  This registers the interfaces
      * with the driver core and lets interface drivers bind to them.
      */
     c = usb_choose_configuration(usb_dev);
     if (c >= 0) {
         result = usb_set_configuration(usb_dev, c);
         if (result) {
             dev_err(&usb_dev->dev,
                 "can't set config #%d, error %d\n", c, result);
             /* This need not be fatal.  The user can try to
              * set other configurations. */
         }
     }
     dev_info(&usb_dev->dev, "authorized to connect\n");
 
 error_device_descriptor:
     usb_autosuspend_device(usb_dev);
 error_autoresume:
 out_authorized:
     usb_unlock_device(usb_dev); /* complements locktree */
     return result;
 }
 
 /**
  * get_port_ssp_rate - Match the extended port status to SSP rate
  * @hdev: The hub device
  * @ext_portstatus: extended port status
  *
  * Match the extended port status speed id to the SuperSpeed Plus sublink speed
  * capability attributes. Base on the number of connected lanes and speed,
  * return the corresponding enum usb_ssp_rate.
  */
 static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev,
                        u32 ext_portstatus)
 {
     struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
     u32 attr;
     u8 speed_id;
     u8 ssac;
     u8 lanes;
     int i;
 
     if (!ssp_cap)
         goto out;
 
     speed_id = ext_portstatus & USB_EXT_PORT_STAT_RX_SPEED_ID;
     lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
 
     ssac = le32_to_cpu(ssp_cap->bmAttributes) &
         USB_SSP_SUBLINK_SPEED_ATTRIBS;
 
     for (i = 0; i <= ssac; i++) {
         u8 ssid;
 
         attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
         ssid = FIELD_GET(USB_SSP_SUBLINK_SPEED_SSID, attr);
         if (speed_id == ssid) {
             u16 mantissa;
             u8 lse;
             u8 type;
 
             /*
              * Note: currently asymmetric lane types are only
              * applicable for SSIC operate in SuperSpeed protocol
              */
             type = FIELD_GET(USB_SSP_SUBLINK_SPEED_ST, attr);
             if (type == USB_SSP_SUBLINK_SPEED_ST_ASYM_RX ||
                 type == USB_SSP_SUBLINK_SPEED_ST_ASYM_TX)
                 goto out;
 
             if (FIELD_GET(USB_SSP_SUBLINK_SPEED_LP, attr) !=
                 USB_SSP_SUBLINK_SPEED_LP_SSP)
                 goto out;
 
             lse = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSE, attr);
             mantissa = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSM, attr);
 
             /* Convert to Gbps */
             for (; lse < USB_SSP_SUBLINK_SPEED_LSE_GBPS; lse++)
                 mantissa /= 1000;
 
             if (mantissa >= 10 && lanes == 1)
                 return USB_SSP_GEN_2x1;
 
             if (mantissa >= 10 && lanes == 2)
                 return USB_SSP_GEN_2x2;
 
             if (mantissa >= 5 && lanes == 2)
                 return USB_SSP_GEN_1x2;
 
             goto out;
         }
     }
 
 out:
     return USB_SSP_GEN_UNKNOWN;
 }
 
 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
 static unsigned hub_is_wusb(struct usb_hub *hub)
 {
     struct usb_hcd *hcd;
     if (hub->hdev->parent != NULL)  /* not a root hub? */
         return 0;
     hcd = bus_to_hcd(hub->hdev->bus);
     return hcd->wireless;
 }
 
 
 #ifdef CONFIG_USB_FEW_INIT_RETRIES
 #define PORT_RESET_TRIES    2
 #define SET_ADDRESS_TRIES   1
 #define GET_DESCRIPTOR_TRIES    1
 #define GET_MAXPACKET0_TRIES    1
 #define PORT_INIT_TRIES     4
 
 #else
 #define PORT_RESET_TRIES    5
 #define SET_ADDRESS_TRIES   2
 #define GET_DESCRIPTOR_TRIES    2
 #define GET_MAXPACKET0_TRIES    3
 #define PORT_INIT_TRIES     4
 #endif  /* CONFIG_USB_FEW_INIT_RETRIES */
 
 #define DETECT_DISCONNECT_TRIES 5
 
 #define HUB_ROOT_RESET_TIME 60  /* times are in msec */
 #define HUB_SHORT_RESET_TIME    10
 #define HUB_BH_RESET_TIME   50
 #define HUB_LONG_RESET_TIME 200
 #define HUB_RESET_TIMEOUT   800
 
 static bool use_new_scheme(struct usb_device *udev, int retry,
                struct usb_port *port_dev)
 {
     int old_scheme_first_port =
         (port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME) ||
         old_scheme_first;
 
     /*
      * "New scheme" enumeration causes an extra state transition to be
      * exposed to an xhci host and causes USB3 devices to receive control
      * commands in the default state.  This has been seen to cause
      * enumeration failures, so disable this enumeration scheme for USB3
      * devices.
      */
     if (udev->speed >= USB_SPEED_SUPER)
         return false;
 
     /*
      * If use_both_schemes is set, use the first scheme (whichever
      * it is) for the larger half of the retries, then use the other
      * scheme.  Otherwise, use the first scheme for all the retries.
      */
     if (use_both_schemes && retry >= (PORT_INIT_TRIES + 1) / 2)
         return old_scheme_first_port;   /* Second half */
     return !old_scheme_first_port;      /* First half or all */
 }
 
 /* Is a USB 3.0 port in the Inactive or Compliance Mode state?
  * Port warm reset is required to recover
  */
 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
         u16 portstatus)
 {
     u16 link_state;
 
     if (!hub_is_superspeed(hub->hdev))
         return false;
 
     if (test_bit(port1, hub->warm_reset_bits))
         return true;
 
     link_state = portstatus & USB_PORT_STAT_LINK_STATE;
     return link_state == USB_SS_PORT_LS_SS_INACTIVE
         || link_state == USB_SS_PORT_LS_COMP_MOD;
 }
 
 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
             struct usb_device *udev, unsigned int delay, bool warm)
 {
     int delay_time, ret;
     u16 portstatus;
     u16 portchange;
     u32 ext_portstatus = 0;
 
     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 */
         if (hub_is_superspeedplus(hub->hdev))
             ret = hub_ext_port_status(hub, port1,
                           HUB_EXT_PORT_STATUS,
                           &portstatus, &portchange,
                           &ext_portstatus);
         else
             ret = usb_hub_port_status(hub, port1, &portstatus,
                           &portchange);
         if (ret < 0)
             return ret;
 
         /*
          * The port state is unknown until the reset completes.
          *
          * On top of that, some chips may require additional time
          * to re-establish a connection after the reset is complete,
          * so also wait for the connection to be re-established.
          */
         if (!(portstatus & USB_PORT_STAT_RESET) &&
             (portstatus & USB_PORT_STAT_CONNECTION))
             break;
 
         /* 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->ports[port1 - 1]->dev,
                 "not %sreset yet, waiting %dms\n",
                 warm ? "warm " : "", delay);
     }
 
     if ((portstatus & USB_PORT_STAT_RESET))
         return -EBUSY;
 
     if (hub_port_warm_reset_required(hub, port1, portstatus))
         return -ENOTCONN;
 
     /* Device went away? */
     if (!(portstatus & USB_PORT_STAT_CONNECTION))
         return -ENOTCONN;
 
     /* Retry if connect change is set but status is still connected.
      * A USB 3.0 connection may bounce if multiple warm resets were issued,
      * but the device may have successfully re-connected. Ignore it.
      */
     if (!hub_is_superspeed(hub->hdev) &&
         (portchange & USB_PORT_STAT_C_CONNECTION)) {
         usb_clear_port_feature(hub->hdev, port1,
                        USB_PORT_FEAT_C_CONNECTION);
         return -EAGAIN;
     }
 
     if (!(portstatus & USB_PORT_STAT_ENABLE))
         return -EBUSY;
 
     if (!udev)
         return 0;
 
     if (hub_is_superspeedplus(hub->hdev)) {
         /* extended portstatus Rx and Tx lane count are zero based */
         udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
         udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
         udev->ssp_rate = get_port_ssp_rate(hub->hdev, ext_portstatus);
     } else {
         udev->rx_lanes = 1;
         udev->tx_lanes = 1;
         udev->ssp_rate = USB_SSP_GEN_UNKNOWN;
     }
     if (hub_is_wusb(hub))
         udev->speed = USB_SPEED_WIRELESS;
     else if (udev->ssp_rate != USB_SSP_GEN_UNKNOWN)
         udev->speed = USB_SPEED_SUPER_PLUS;
     else if (hub_is_superspeed(hub->hdev))
         udev->speed = USB_SPEED_SUPER;
     else 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;
 }
 
 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
 static int hub_port_reset(struct usb_hub *hub, int port1,
             struct usb_device *udev, unsigned int delay, bool warm)
 {
     int i, status;
     u16 portchange, portstatus;
     struct usb_port *port_dev = hub->ports[port1 - 1];
     int reset_recovery_time;
 
     if (!hub_is_superspeed(hub->hdev)) {
         if (warm) {
             dev_err(hub->intfdev, "only USB3 hub support "
                         "warm reset\n");
             return -EINVAL;
         }
         /* Block EHCI CF initialization during the port reset.
          * Some companion controllers don't like it when they mix.
          */
         down_read(&ehci_cf_port_reset_rwsem);
     } else if (!warm) {
         /*
          * If the caller hasn't explicitly requested a warm reset,
          * double check and see if one is needed.
          */
         if (usb_hub_port_status(hub, port1, &portstatus,
                     &portchange) == 0)
             if (hub_port_warm_reset_required(hub, port1,
                             portstatus))
                 warm = true;
     }
     clear_bit(port1, hub->warm_reset_bits);
 
     /* Reset the port */
     for (i = 0; i < PORT_RESET_TRIES; i++) {
         status = set_port_feature(hub->hdev, port1, (warm ?
                     USB_PORT_FEAT_BH_PORT_RESET :
                     USB_PORT_FEAT_RESET));
         if (status == -ENODEV) {
             ;   /* The hub is gone */
         } else if (status) {
             dev_err(&port_dev->dev,
                     "cannot %sreset (err = %d)\n",
                     warm ? "warm " : "", status);
         } else {
             status = hub_port_wait_reset(hub, port1, udev, delay,
                                 warm);
             if (status && status != -ENOTCONN && status != -ENODEV)
                 dev_dbg(hub->intfdev,
                         "port_wait_reset: err = %d\n",
                         status);
         }
 
         /*
          * Check for disconnect or reset, and bail out after several
          * reset attempts to avoid warm reset loop.
          */
         if (status == 0 || status == -ENOTCONN || status == -ENODEV ||
             (status == -EBUSY && i == PORT_RESET_TRIES - 1)) {
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_RESET);
 
             if (!hub_is_superspeed(hub->hdev))
                 goto done;
 
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_BH_PORT_RESET);
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_PORT_LINK_STATE);
 
             if (udev)
                 usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_CONNECTION);
 
             /*
              * If a USB 3.0 device migrates from reset to an error
              * state, re-issue the warm reset.
              */
             if (usb_hub_port_status(hub, port1,
                     &portstatus, &portchange) < 0)
                 goto done;
 
             if (!hub_port_warm_reset_required(hub, port1,
                     portstatus))
                 goto done;
 
             /*
              * If the port is in SS.Inactive or Compliance Mode, the
              * hot or warm reset failed.  Try another warm reset.
              */
             if (!warm) {
                 dev_dbg(&port_dev->dev,
                         "hot reset failed, warm reset\n");
                 warm = true;
             }
         }
 
         dev_dbg(&port_dev->dev,
                 "not enabled, trying %sreset again...\n",
                 warm ? "warm " : "");
         delay = HUB_LONG_RESET_TIME;
     }
 
     dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
 
 done:
     if (status == 0) {
         if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
             usleep_range(10000, 12000);
         else {
             /* TRSTRCY = 10 ms; plus some extra */
             reset_recovery_time = 10 + 40;
 
             /* Hub needs extra delay after resetting its port. */
             if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
                 reset_recovery_time += 100;
 
             msleep(reset_recovery_time);
         }
 
         if (udev) {
             struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
             update_devnum(udev, 0);
             /* The xHC may think the device is already reset,
              * so ignore the status.
              */
             if (hcd->driver->reset_device)
                 hcd->driver->reset_device(hcd, udev);
 
             usb_set_device_state(udev, USB_STATE_DEFAULT);
         }
     } else {
         if (udev)
             usb_set_device_state(udev, USB_STATE_NOTATTACHED);
     }
 
     if (!hub_is_superspeed(hub->hdev))
         up_read(&ehci_cf_port_reset_rwsem);
 
     return status;
 }
 
 /* Check if a port is power on */
 int usb_port_is_power_on(struct usb_hub *hub, unsigned int portstatus)
 {
     int ret = 0;
 
     if (hub_is_superspeed(hub->hdev)) {
         if (portstatus & USB_SS_PORT_STAT_POWER)
             ret = 1;
     } else {
         if (portstatus & USB_PORT_STAT_POWER)
             ret = 1;
     }
 
     return ret;
 }
 
 static void usb_lock_port(struct usb_port *port_dev)
         __acquires(&port_dev->status_lock)
 {
     mutex_lock(&port_dev->status_lock);
     __acquire(&port_dev->status_lock);
 }
 
 static void usb_unlock_port(struct usb_port *port_dev)
         __releases(&port_dev->status_lock)
 {
     mutex_unlock(&port_dev->status_lock);
     __release(&port_dev->status_lock);
 }
 
 #ifdef  CONFIG_PM
 
 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
 {
     int ret = 0;
 
     if (hub_is_superspeed(hub->hdev)) {
         if ((portstatus & USB_PORT_STAT_LINK_STATE)
                 == USB_SS_PORT_LS_U3)
             ret = 1;
     } else {
         if (portstatus & USB_PORT_STAT_SUSPEND)
             ret = 1;
     }
 
     return ret;
 }
 
 /* Determine whether the device on a port is ready for a normal resume,
  * is ready for a reset-resume, or should be disconnected.
  */
 static int check_port_resume_type(struct usb_device *udev,
         struct usb_hub *hub, int port1,
         int status, u16 portchange, u16 portstatus)
 {
     struct usb_port *port_dev = hub->ports[port1 - 1];
     int retries = 3;
 
  retry:
     /* Is a warm reset needed to recover the connection? */
     if (status == 0 && udev->reset_resume
         && hub_port_warm_reset_required(hub, port1, portstatus)) {
         /* pass */;
     }
     /* Is the device still present? */
     else if (status || port_is_suspended(hub, portstatus) ||
             !usb_port_is_power_on(hub, portstatus)) {
         if (status >= 0)
             status = -ENODEV;
     } else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
         if (retries--) {
             usleep_range(200, 300);
             status = usb_hub_port_status(hub, port1, &portstatus,
                                  &portchange);
             goto retry;
         }
         status = -ENODEV;
     }
 
     /* Can't do a normal resume if the port isn't enabled,
      * so try a reset-resume instead.
      */
     else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
         if (udev->persist_enabled)
             udev->reset_resume = 1;
         else
             status = -ENODEV;
     }
 
     if (status) {
         dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
                 portchange, portstatus, status);
     } else if (udev->reset_resume) {
 
         /* Late port handoff can set status-change bits */
         if (portchange & USB_PORT_STAT_C_CONNECTION)
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_CONNECTION);
         if (portchange & USB_PORT_STAT_C_ENABLE)
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_ENABLE);
 
         /*
          * Whatever made this reset-resume necessary may have
          * turned on the port1 bit in hub->change_bits.  But after
          * a successful reset-resume we want the bit to be clear;
          * if it was on it would indicate that something happened
          * following the reset-resume.
          */
         clear_bit(port1, hub->change_bits);
     }
 
     return status;
 }
 
 int usb_disable_ltm(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     /* Check if the roothub and device supports LTM. */
     if (!usb_device_supports_ltm(hcd->self.root_hub) ||
             !usb_device_supports_ltm(udev))
         return 0;
 
     /* Clear Feature LTM Enable can only be sent if the device is
      * configured.
      */
     if (!udev->actconfig)
         return 0;
 
     return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
             USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
             USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
             USB_CTRL_SET_TIMEOUT);
 }
 EXPORT_SYMBOL_GPL(usb_disable_ltm);
 
 void usb_enable_ltm(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     /* Check if the roothub and device supports LTM. */
     if (!usb_device_supports_ltm(hcd->self.root_hub) ||
             !usb_device_supports_ltm(udev))
         return;
 
     /* Set Feature LTM Enable can only be sent if the device is
      * configured.
      */
     if (!udev->actconfig)
         return;
 
     usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
             USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
             USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
             USB_CTRL_SET_TIMEOUT);
 }
 EXPORT_SYMBOL_GPL(usb_enable_ltm);
 
 /*
  * usb_enable_remote_wakeup - enable remote wakeup for a device
  * @udev: target device
  *
  * For USB-2 devices: Set the device's remote wakeup feature.
  *
  * For USB-3 devices: Assume there's only one function on the device and
  * enable remote wake for the first interface.  FIXME if the interface
  * association descriptor shows there's more than one function.
  */
 static int usb_enable_remote_wakeup(struct usb_device *udev)
 {
     if (udev->speed < USB_SPEED_SUPER)
         return 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);
     else
         return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                 USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
                 USB_INTRF_FUNC_SUSPEND,
                 USB_INTRF_FUNC_SUSPEND_RW |
                     USB_INTRF_FUNC_SUSPEND_LP,
                 NULL, 0, USB_CTRL_SET_TIMEOUT);
 }
 
 /*
  * usb_disable_remote_wakeup - disable remote wakeup for a device
  * @udev: target device
  *
  * For USB-2 devices: Clear the device's remote wakeup feature.
  *
  * For USB-3 devices: Assume there's only one function on the device and
  * disable remote wake for the first interface.  FIXME if the interface
  * association descriptor shows there's more than one function.
  */
 static int usb_disable_remote_wakeup(struct usb_device *udev)
 {
     if (udev->speed < USB_SPEED_SUPER)
         return 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
         return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                 USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
                 USB_INTRF_FUNC_SUSPEND, 0, NULL, 0,
                 USB_CTRL_SET_TIMEOUT);
 }
 
 /* Count of wakeup-enabled devices at or below udev */
 unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(udev);
 
     return udev->do_remote_wakeup +
             (hub ? hub->wakeup_enabled_descendants : 0);
 }
 EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
 
 /*
  * usb_port_suspend - suspend a usb device's upstream port
  * @udev: device that's no longer in active use, not a root hub
  * Context: must be able to sleep; device not locked; pm locks held
  *
  * 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_port_resume().  It's also routine
  * to disconnect devices while they are suspended.
  *
  * This only affects the USB hardware for a device; its interfaces
  * (and, for hubs, child devices) must already have been suspended.
  *
  * 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.
  *
  * 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.
  *
  * Devices on USB hub ports have only one "suspend" state, corresponding
  * to ACPI D2, "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 hub_wq
  * timer, no SRP, no requests through sysfs.
  *
  * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
  * suspended until their bus goes into global suspend (i.e., the root
  * hub is suspended).  Nevertheless, we change @udev->state to
  * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
  * upstream port setting is stored in @udev->port_is_suspended.
  *
  * Returns 0 on success, else negative errno.
  */
 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 {
     struct usb_hub  *hub = usb_hub_to_struct_hub(udev->parent);
     struct usb_port *port_dev = hub->ports[udev->portnum - 1];
     int     port1 = udev->portnum;
     int     status;
     bool        really_suspend = true;
 
     usb_lock_port(port_dev);
 
     /* 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->do_remote_wakeup) {
         status = usb_enable_remote_wakeup(udev);
         if (status) {
             dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
                     status);
             /* bail if autosuspend is requested */
             if (PMSG_IS_AUTO(msg))
                 goto err_wakeup;
         }
     }
 
     /* disable USB2 hardware LPM */
     usb_disable_usb2_hardware_lpm(udev);
 
     if (usb_disable_ltm(udev)) {
         dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
         status = -ENOMEM;
         if (PMSG_IS_AUTO(msg))
             goto err_ltm;
     }
 
     /* see 7.1.7.6 */
     if (hub_is_superspeed(hub->hdev))
         status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
 
     /*
      * For system suspend, we do not need to enable the suspend feature
      * on individual USB-2 ports.  The devices will automatically go
      * into suspend a few ms after the root hub stops sending packets.
      * The USB 2.0 spec calls this "global suspend".
      *
      * However, many USB hubs have a bug: They don't relay wakeup requests
      * from a downstream port if the port's suspend feature isn't on.
      * Therefore we will turn on the suspend feature if udev or any of its
      * descendants is enabled for remote wakeup.
      */
     else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
         status = set_port_feature(hub->hdev, port1,
                 USB_PORT_FEAT_SUSPEND);
     else {
         really_suspend = false;
         status = 0;
     }
     if (status) {
         /* Check if the port has been suspended for the timeout case
          * to prevent the suspended port from incorrect handling.
          */
         if (status == -ETIMEDOUT) {
             int ret;
             u16 portstatus, portchange;
 
             portstatus = portchange = 0;
             ret = usb_hub_port_status(hub, port1, &portstatus,
                     &portchange);
 
             dev_dbg(&port_dev->dev,
                 "suspend timeout, status %04x\n", portstatus);
 
             if (ret == 0 && port_is_suspended(hub, portstatus)) {
                 status = 0;
                 goto suspend_done;
             }
         }
 
         dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
 
         /* Try to enable USB3 LTM again */
         usb_enable_ltm(udev);
  err_ltm:
         /* Try to enable USB2 hardware LPM again */
         usb_enable_usb2_hardware_lpm(udev);
 
         if (udev->do_remote_wakeup)
             (void) usb_disable_remote_wakeup(udev);
  err_wakeup:
 
         /* System sleep transitions should never fail */
         if (!PMSG_IS_AUTO(msg))
             status = 0;
     } else {
  suspend_done:
         dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
                 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
                 udev->do_remote_wakeup);
         if (really_suspend) {
             udev->port_is_suspended = 1;
 
             /* device has up to 10 msec to fully suspend */
             msleep(10);
         }
         usb_set_device_state(udev, USB_STATE_SUSPENDED);
     }
 
     if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
             && test_and_clear_bit(port1, hub->child_usage_bits))
         pm_runtime_put_sync(&port_dev->dev);
 
     usb_mark_last_busy(hub->hdev);
 
     usb_unlock_port(port_dev);
     return status;
 }
 
 /*
  * If the USB "suspend" state is in use (rather than "global suspend"),
  * many devices will be individually taken out of suspend state using
  * special "resume" signaling.  This routine kicks in shortly after
  * 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.
  *
  * If @udev->reset_resume is set then the device is reset before the
  * status check is done.
  */
 static int finish_port_resume(struct usb_device *udev)
 {
     int status = 0;
     u16 devstatus = 0;
 
     /* caller owns the udev device lock */
     dev_dbg(&udev->dev, "%s\n",
         udev->reset_resume ? "finish reset-resume" : "finish resume");
 
     /* 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 hub_wq can't suspend until later.
      */
     usb_set_device_state(udev, udev->actconfig
             ? USB_STATE_CONFIGURED
             : USB_STATE_ADDRESS);
 
     /* 10.5.4.5 says not to reset a suspended port if the attached
      * device is enabled for remote wakeup.  Hence the reset
      * operation is carried out here, after the port has been
      * resumed.
      */
     if (udev->reset_resume) {
         /*
          * If the device morphs or switches modes when it is reset,
          * we don't want to perform a reset-resume.  We'll fail the
          * resume, which will cause a logical disconnect, and then
          * the device will be rediscovered.
          */
  retry_reset_resume:
         if (udev->quirks & USB_QUIRK_RESET)
             status = -ENODEV;
         else
             status = usb_reset_and_verify_device(udev);
     }
 
     /* 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.
      */
     if (status == 0) {
         devstatus = 0;
         status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
 
         /* If a normal resume failed, try doing a reset-resume */
         if (status && !udev->reset_resume && udev->persist_enabled) {
             dev_dbg(&udev->dev, "retry with reset-resume\n");
             udev->reset_resume = 1;
             goto retry_reset_resume;
         }
     }
 
     if (status) {
         dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
                 status);
     /*
      * There are a few quirky devices which violate the standard
      * by claiming to have remote wakeup enabled after a reset,
      * which crash if the feature is cleared, hence check for
      * udev->reset_resume
      */
     } else if (udev->actconfig && !udev->reset_resume) {
         if (udev->speed < USB_SPEED_SUPER) {
             if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
                 status = usb_disable_remote_wakeup(udev);
         } else {
             status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
                     &devstatus);
             if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
                     | USB_INTRF_STAT_FUNC_RW))
                 status = usb_disable_remote_wakeup(udev);
         }
 
         if (status)
             dev_dbg(&udev->dev,
                 "disable remote wakeup, status %d\n",
                 status);
         status = 0;
     }
     return status;
 }
 
 /*
  * There are some SS USB devices which take longer time for link training.
  * XHCI specs 4.19.4 says that when Link training is successful, port
  * sets CCS bit to 1. So if SW reads port status before successful link
  * training, then it will not find device to be present.
  * USB Analyzer log with such buggy devices show that in some cases
  * device switch on the RX termination after long delay of host enabling
  * the VBUS. In few other cases it has been seen that device fails to
  * negotiate link training in first attempt. It has been
  * reported till now that few devices take as long as 2000 ms to train
  * the link after host enabling its VBUS and termination. Following
  * routine implements a 2000 ms timeout for link training. If in a case
  * link trains before timeout, loop will exit earlier.
  *
  * There are also some 2.0 hard drive based devices and 3.0 thumb
  * drives that, when plugged into a 2.0 only port, take a long
  * time to set CCS after VBUS enable.
  *
  * FIXME: If a device was connected before suspend, but was removed
  * while system was asleep, then the loop in the following routine will
  * only exit at timeout.
  *
  * This routine should only be called when persist is enabled.
  */
 static int wait_for_connected(struct usb_device *udev,
         struct usb_hub *hub, int port1,
         u16 *portchange, u16 *portstatus)
 {
     int status = 0, delay_ms = 0;
 
     while (delay_ms < 2000) {
         if (status || *portstatus & USB_PORT_STAT_CONNECTION)
             break;
         if (!usb_port_is_power_on(hub, *portstatus)) {
             status = -ENODEV;
             break;
         }
         msleep(20);
         delay_ms += 20;
         status = usb_hub_port_status(hub, port1, portstatus, portchange);
     }
     dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
     return status;
 }
 
 /*
  * usb_port_resume - re-activate a suspended usb device's upstream port
  * @udev: device to re-activate, not a root hub
  * Context: must be able to sleep; device not locked; pm locks held
  *
  * 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.
  *
  * If @udev->reset_resume is set then this routine won't check that the
  * port is still enabled.  Furthermore, finish_port_resume() above will
  * reset @udev.  The end result is that a broken power session can be
  * recovered and @udev will appear to persist across a loss of VBUS power.
  *
  * For example, if a host controller doesn't maintain VBUS suspend current
  * during a system sleep or is reset when the system wakes up, all the USB
  * power sessions below it will be broken.  This is especially troublesome
  * for mass-storage devices containing mounted filesystems, since the
  * device will appear to have disconnected and all the memory mappings
  * to it will be lost.  Using the USB_PERSIST facility, the device can be
  * made to appear as if it had not disconnected.
  *
  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
  * every effort to insure that the same device is present after the
  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
  * quite possible for a device to remain unaltered but its media to be
  * changed.  If the user replaces a flash memory card while the system is
  * asleep, he will have only himself to blame when the filesystem on the
  * new card is corrupted and the system crashes.
  *
  * Returns 0 on success, else negative errno.
  */
 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 {
     struct usb_hub  *hub = usb_hub_to_struct_hub(udev->parent);
     struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
     int     port1 = udev->portnum;
     int     status;
     u16     portchange, portstatus;
 
     if (!test_and_set_bit(port1, hub->child_usage_bits)) {
         status = pm_runtime_resume_and_get(&port_dev->dev);
         if (status < 0) {
             dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
                     status);
             return status;
         }
     }
 
     usb_lock_port(port_dev);
 
     /* Skip the initial Clear-Suspend step for a remote wakeup */
     status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
     if (status == 0 && !port_is_suspended(hub, portstatus)) {
         if (portchange & USB_PORT_STAT_C_SUSPEND)
             pm_wakeup_event(&udev->dev, 0);
         goto SuspendCleared;
     }
 
     /* see 7.1.7.7; affects power usage, but not budgeting */
     if (hub_is_superspeed(hub->hdev))
         status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
     else
         status = usb_clear_port_feature(hub->hdev,
                 port1, USB_PORT_FEAT_SUSPEND);
     if (status) {
         dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
     } else {
         /* drive resume for USB_RESUME_TIMEOUT msec */
         dev_dbg(&udev->dev, "usb %sresume\n",
                 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
         msleep(USB_RESUME_TIMEOUT);
 
         /* Virtual root hubs can trigger on GET_PORT_STATUS to
          * stop resume signaling.  Then finish the resume
          * sequence.
          */
         status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
     }
 
  SuspendCleared:
     if (status == 0) {
         udev->port_is_suspended = 0;
         if (hub_is_superspeed(hub->hdev)) {
             if (portchange & USB_PORT_STAT_C_LINK_STATE)
                 usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_PORT_LINK_STATE);
         } else {
             if (portchange & USB_PORT_STAT_C_SUSPEND)
                 usb_clear_port_feature(hub->hdev, port1,
                         USB_PORT_FEAT_C_SUSPEND);
         }
 
         /* TRSMRCY = 10 msec */
         msleep(10);
     }
 
     if (udev->persist_enabled)
         status = wait_for_connected(udev, hub, port1, &portchange,
                 &portstatus);
 
     status = check_port_resume_type(udev,
             hub, port1, status, portchange, portstatus);
     if (status == 0)
         status = finish_port_resume(udev);
     if (status < 0) {
         dev_dbg(&udev->dev, "can't resume, status %d\n", status);
         hub_port_logical_disconnect(hub, port1);
     } else  {
         /* Try to enable USB2 hardware LPM */
         usb_enable_usb2_hardware_lpm(udev);
 
         /* Try to enable USB3 LTM */
         usb_enable_ltm(udev);
     }
 
     usb_unlock_port(port_dev);
 
     return status;
 }
 
 int usb_remote_wakeup(struct usb_device *udev)
 {
     int status = 0;
 
     usb_lock_device(udev);
     if (udev->state == USB_STATE_SUSPENDED) {
         dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
         status = usb_autoresume_device(udev);
         if (status == 0) {
             /* Let the drivers do their thing, then... */
             usb_autosuspend_device(udev);
         }
     }
     usb_unlock_device(udev);
     return status;
 }
 
 /* Returns 1 if there was a remote wakeup and a connect status change. */
 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
         u16 portstatus, u16 portchange)
         __must_hold(&port_dev->status_lock)
 {
     struct usb_port *port_dev = hub->ports[port - 1];
     struct usb_device *hdev;
     struct usb_device *udev;
     int connect_change = 0;
     u16 link_state;
     int ret;
 
     hdev = hub->hdev;
     udev = port_dev->child;
     if (!hub_is_superspeed(hdev)) {
         if (!(portchange & USB_PORT_STAT_C_SUSPEND))
             return 0;
         usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
     } else {
         link_state = portstatus & USB_PORT_STAT_LINK_STATE;
         if (!udev || udev->state != USB_STATE_SUSPENDED ||
                 (link_state != USB_SS_PORT_LS_U0 &&
                  link_state != USB_SS_PORT_LS_U1 &&
                  link_state != USB_SS_PORT_LS_U2))
             return 0;
     }
 
     if (udev) {
         /* TRSMRCY = 10 msec */
         msleep(10);
 
         usb_unlock_port(port_dev);
         ret = usb_remote_wakeup(udev);
         usb_lock_port(port_dev);
         if (ret < 0)
             connect_change = 1;
     } else {
         ret = -ENODEV;
         hub_port_disable(hub, port, 1);
     }
     dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
     return connect_change;
 }
 
 static int check_ports_changed(struct usb_hub *hub)
 {
     int port1;
 
     for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
         u16 portstatus, portchange;
         int status;
 
         status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
         if (!status && portchange)
             return 1;
     }
     return 0;
 }
 
 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
 {
     struct usb_hub      *hub = usb_get_intfdata(intf);
     struct usb_device   *hdev = hub->hdev;
     unsigned        port1;
 
     /*
      * Warn if children aren't already suspended.
      * Also, add up the number of wakeup-enabled descendants.
      */
     hub->wakeup_enabled_descendants = 0;
     for (port1 = 1; port1 <= hdev->maxchild; port1++) {
         struct usb_port *port_dev = hub->ports[port1 - 1];
         struct usb_device *udev = port_dev->child;
 
         if (udev && udev->can_submit) {
             dev_warn(&port_dev->dev, "device %s not suspended yet\n",
                     dev_name(&udev->dev));
             if (PMSG_IS_AUTO(msg))
                 return -EBUSY;
         }
         if (udev)
             hub->wakeup_enabled_descendants +=
                     usb_wakeup_enabled_descendants(udev);
     }
 
     if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
         /* check if there are changes pending on hub ports */
         if (check_ports_changed(hub)) {
             if (PMSG_IS_AUTO(msg))
                 return -EBUSY;
             pm_wakeup_event(&hdev->dev, 2000);
         }
     }
 
     if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
         /* Enable hub to send remote wakeup for all ports. */
         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
             set_port_feature(hdev,
                      port1 |
                      USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
                      USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
                      USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
                      USB_PORT_FEAT_REMOTE_WAKE_MASK);
         }
     }
 
     dev_dbg(&intf->dev, "%s\n", __func__);
 
     /* stop hub_wq and related activity */
     hub_quiesce(hub, HUB_SUSPEND);
     return 0;
 }
 
 /* Report wakeup requests from the ports of a resuming root hub */
 static void report_wakeup_requests(struct usb_hub *hub)
 {
     struct usb_device   *hdev = hub->hdev;
     struct usb_device   *udev;
     struct usb_hcd      *hcd;
     unsigned long       resuming_ports;
     int         i;
 
     if (hdev->parent)
         return;     /* Not a root hub */
 
     hcd = bus_to_hcd(hdev->bus);
     if (hcd->driver->get_resuming_ports) {
 
         /*
          * The get_resuming_ports() method returns a bitmap (origin 0)
          * of ports which have started wakeup signaling but have not
          * yet finished resuming.  During system resume we will
          * resume all the enabled ports, regardless of any wakeup
          * signals, which means the wakeup requests would be lost.
          * To prevent this, report them to the PM core here.
          */
         resuming_ports = hcd->driver->get_resuming_ports(hcd);
         for (i = 0; i < hdev->maxchild; ++i) {
             if (test_bit(i, &resuming_ports)) {
                 udev = hub->ports[i]->child;
                 if (udev)
                     pm_wakeup_event(&udev->dev, 0);
             }
         }
     }
 }
 
 static int hub_resume(struct usb_interface *intf)
 {
     struct usb_hub *hub = usb_get_intfdata(intf);
 
     dev_dbg(&intf->dev, "%s\n", __func__);
     hub_activate(hub, HUB_RESUME);
 
     /*
      * This should be called only for system resume, not runtime resume.
      * We can't tell the difference here, so some wakeup requests will be
      * reported at the wrong time or more than once.  This shouldn't
      * matter much, so long as they do get reported.
      */
     report_wakeup_requests(hub);
     return 0;
 }
 
 static int hub_reset_resume(struct usb_interface *intf)
 {
     struct usb_hub *hub = usb_get_intfdata(intf);
 
     dev_dbg(&intf->dev, "%s\n", __func__);
     hub_activate(hub, HUB_RESET_RESUME);
     return 0;
 }
 
 /**
  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
  * @rhdev: struct usb_device for the root hub
  *
  * The USB host controller driver calls this function when its root hub
  * is resumed and Vbus power has been interrupted or the controller
  * has been reset.  The routine marks @rhdev as having lost power.
  * When the hub driver is resumed it will take notice and carry out
  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
  * the others will be disconnected.
  */
 void usb_root_hub_lost_power(struct usb_device *rhdev)
 {
     dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
     rhdev->reset_resume = 1;
 }
 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
 
 static const char * const usb3_lpm_names[]  = {
     "U0",
     "U1",
     "U2",
     "U3",
 };
 
 /*
  * Send a Set SEL control transfer to the device, prior to enabling
  * device-initiated U1 or U2.  This lets the device know the exit latencies from
  * the time the device initiates a U1 or U2 exit, to the time it will receive a
  * packet from the host.
  *
  * This function will fail if the SEL or PEL values for udev are greater than
  * the maximum allowed values for the link state to be enabled.
  */
 static int usb_req_set_sel(struct usb_device *udev)
 {
     struct usb_set_sel_req *sel_values;
     unsigned long long u1_sel;
     unsigned long long u1_pel;
     unsigned long long u2_sel;
     unsigned long long u2_pel;
     int ret;
 
     if (!udev->parent || udev->speed < USB_SPEED_SUPER || !udev->lpm_capable)
         return 0;
 
     /* Convert SEL and PEL stored in ns to us */
     u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
     u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
     u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
     u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
 
     /*
      * Make sure that the calculated SEL and PEL values for the link
      * state we're enabling aren't bigger than the max SEL/PEL
      * value that will fit in the SET SEL control transfer.
      * Otherwise the device would get an incorrect idea of the exit
      * latency for the link state, and could start a device-initiated
      * U1/U2 when the exit latencies are too high.
      */
     if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
         u1_pel > USB3_LPM_MAX_U1_SEL_PEL ||
         u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
         u2_pel > USB3_LPM_MAX_U2_SEL_PEL) {
         dev_dbg(&udev->dev, "Device-initiated U1/U2 disabled due to long SEL or PEL\n");
         return -EINVAL;
     }
 
     /*
      * usb_enable_lpm() can be called as part of a failed device reset,
      * which may be initiated by an error path of a mass storage driver.
      * Therefore, use GFP_NOIO.
      */
     sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
     if (!sel_values)
         return -ENOMEM;
 
     sel_values->u1_sel = u1_sel;
     sel_values->u1_pel = u1_pel;
     sel_values->u2_sel = cpu_to_le16(u2_sel);
     sel_values->u2_pel = cpu_to_le16(u2_pel);
 
     ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
             USB_REQ_SET_SEL,
             USB_RECIP_DEVICE,
             0, 0,
             sel_values, sizeof *(sel_values),
             USB_CTRL_SET_TIMEOUT);
     kfree(sel_values);
 
     if (ret > 0)
         udev->lpm_devinit_allow = 1;
 
     return ret;
 }
 
 /*
  * Enable or disable device-initiated U1 or U2 transitions.
  */
 static int usb_set_device_initiated_lpm(struct usb_device *udev,
         enum usb3_link_state state, bool enable)
 {
     int ret;
     int feature;
 
     switch (state) {
     case USB3_LPM_U1:
         feature = USB_DEVICE_U1_ENABLE;
         break;
     case USB3_LPM_U2:
         feature = USB_DEVICE_U2_ENABLE;
         break;
     default:
         dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
                 __func__, enable ? "enable" : "disable");
         return -EINVAL;
     }
 
     if (udev->state != USB_STATE_CONFIGURED) {
         dev_dbg(&udev->dev, "%s: Can't %s %s state "
                 "for unconfigured device.\n",
                 __func__, enable ? "enable" : "disable",
                 usb3_lpm_names[state]);
         return 0;
     }
 
     if (enable) {
         /*
          * Now send the control transfer to enable device-initiated LPM
          * for either U1 or U2.
          */
         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                 USB_REQ_SET_FEATURE,
                 USB_RECIP_DEVICE,
                 feature,
                 0, NULL, 0,
                 USB_CTRL_SET_TIMEOUT);
     } else {
         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                 USB_REQ_CLEAR_FEATURE,
                 USB_RECIP_DEVICE,
                 feature,
                 0, NULL, 0,
                 USB_CTRL_SET_TIMEOUT);
     }
     if (ret < 0) {
         dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
                 enable ? "Enable" : "Disable",
                 usb3_lpm_names[state]);
         return -EBUSY;
     }
     return 0;
 }
 
 static int usb_set_lpm_timeout(struct usb_device *udev,
         enum usb3_link_state state, int timeout)
 {
     int ret;
     int feature;
 
     switch (state) {
     case USB3_LPM_U1:
         feature = USB_PORT_FEAT_U1_TIMEOUT;
         break;
     case USB3_LPM_U2:
         feature = USB_PORT_FEAT_U2_TIMEOUT;
         break;
     default:
         dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
                 __func__);
         return -EINVAL;
     }
 
     if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
             timeout != USB3_LPM_DEVICE_INITIATED) {
         dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
                 "which is a reserved value.\n",
                 usb3_lpm_names[state], timeout);
         return -EINVAL;
     }
 
     ret = set_port_feature(udev->parent,
             USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
             feature);
     if (ret < 0) {
         dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
                 "error code %i\n", usb3_lpm_names[state],
                 timeout, ret);
         return -EBUSY;
     }
     if (state == USB3_LPM_U1)
         udev->u1_params.timeout = timeout;
     else
         udev->u2_params.timeout = timeout;
     return 0;
 }
 
 /*
  * Don't allow device intiated U1/U2 if the system exit latency + one bus
  * interval is greater than the minimum service interval of any active
  * periodic endpoint. See USB 3.2 section 9.4.9
  */
 static bool usb_device_may_initiate_lpm(struct usb_device *udev,
                     enum usb3_link_state state)
 {
     unsigned int sel;       /* us */
     int i, j;
 
     if (!udev->lpm_devinit_allow)
         return false;
 
     if (state == USB3_LPM_U1)
         sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
     else if (state == USB3_LPM_U2)
         sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
     else
         return false;
 
     for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
         struct usb_interface *intf;
         struct usb_endpoint_descriptor *desc;
         unsigned int interval;
 
         intf = udev->actconfig->interface[i];
         if (!intf)
             continue;
 
         for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++) {
             desc = &intf->cur_altsetting->endpoint[j].desc;
 
             if (usb_endpoint_xfer_int(desc) ||
                 usb_endpoint_xfer_isoc(desc)) {
                 interval = (1 << (desc->bInterval - 1)) * 125;
                 if (sel + 125 > interval)
                     return false;
             }
         }
     }
     return true;
 }
 
 /*
  * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
  * U1/U2 entry.
  *
  * We will attempt to enable U1 or U2, but there are no guarantees that the
  * control transfers to set the hub timeout or enable device-initiated U1/U2
  * will be successful.
  *
  * If the control transfer to enable device-initiated U1/U2 entry fails, then
  * hub-initiated U1/U2 will be disabled.
  *
  * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
  * driver know about it.  If that call fails, it should be harmless, and just
  * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
  */
 static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
         enum usb3_link_state state)
 {
     int timeout;
     __u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
     __le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
 
     /* If the device says it doesn't have *any* exit latency to come out of
      * U1 or U2, it's probably lying.  Assume it doesn't implement that link
      * state.
      */
     if ((state == USB3_LPM_U1 && u1_mel == 0) ||
             (state == USB3_LPM_U2 && u2_mel == 0))
         return;
 
     /* We allow the host controller to set the U1/U2 timeout internally
      * first, so that it can change its schedule to account for the
      * additional latency to send data to a device in a lower power
      * link state.
      */
     timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
 
     /* xHCI host controller doesn't want to enable this LPM state. */
     if (timeout == 0)
         return;
 
     if (timeout < 0) {
         dev_warn(&udev->dev, "Could not enable %s link state, "
                 "xHCI error %i.\n", usb3_lpm_names[state],
                 timeout);
         return;
     }
 
     if (usb_set_lpm_timeout(udev, state, timeout)) {
         /* If we can't set the parent hub U1/U2 timeout,
          * device-initiated LPM won't be allowed either, so let the xHCI
          * host know that this link state won't be enabled.
          */
         hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
         return;
     }
 
     /* Only a configured device will accept the Set Feature
      * U1/U2_ENABLE
      */
     if (udev->actconfig &&
         usb_device_may_initiate_lpm(udev, state)) {
         if (usb_set_device_initiated_lpm(udev, state, true)) {
             /*
              * Request to enable device initiated U1/U2 failed,
              * better to turn off lpm in this case.
              */
             usb_set_lpm_timeout(udev, state, 0);
             hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
             return;
         }
     }
 
     if (state == USB3_LPM_U1)
         udev->usb3_lpm_u1_enabled = 1;
     else if (state == USB3_LPM_U2)
         udev->usb3_lpm_u2_enabled = 1;
 }
 /*
  * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
  * U1/U2 entry.
  *
  * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
  * If zero is returned, the parent will not allow the link to go into U1/U2.
  *
  * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
  * it won't have an effect on the bus link state because the parent hub will
  * still disallow device-initiated U1/U2 entry.
  *
  * If zero is returned, the xHCI host controller may still think U1/U2 entry is
  * possible.  The result will be slightly more bus bandwidth will be taken up
  * (to account for U1/U2 exit latency), but it should be harmless.
  */
 static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
         enum usb3_link_state state)
 {
     switch (state) {
     case USB3_LPM_U1:
     case USB3_LPM_U2:
         break;
     default:
         dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
                 __func__);
         return -EINVAL;
     }
 
     if (usb_set_lpm_timeout(udev, state, 0))
         return -EBUSY;
 
     usb_set_device_initiated_lpm(udev, state, false);
 
     if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
         dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
                 "bus schedule bandwidth may be impacted.\n",
                 usb3_lpm_names[state]);
 
     /* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
      * is disabled. Hub will disallows link to enter U1/U2 as well,
      * even device is initiating LPM. Hence LPM is disabled if hub LPM
      * timeout set to 0, no matter device-initiated LPM is disabled or
      * not.
      */
     if (state == USB3_LPM_U1)
         udev->usb3_lpm_u1_enabled = 0;
     else if (state == USB3_LPM_U2)
         udev->usb3_lpm_u2_enabled = 0;
 
     return 0;
 }
 
 /*
  * Disable hub-initiated and device-initiated U1 and U2 entry.
  * Caller must own the bandwidth_mutex.
  *
  * This will call usb_enable_lpm() on failure, which will decrement
  * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
  */
 int usb_disable_lpm(struct usb_device *udev)
 {
     struct usb_hcd *hcd;
 
     if (!udev || !udev->parent ||
             udev->speed < USB_SPEED_SUPER ||
             !udev->lpm_capable ||
             udev->state < USB_STATE_CONFIGURED)
         return 0;
 
     hcd = bus_to_hcd(udev->bus);
     if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
         return 0;
 
     udev->lpm_disable_count++;
     if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
         return 0;
 
     /* If LPM is enabled, attempt to disable it. */
     if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
         goto enable_lpm;
     if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
         goto enable_lpm;
 
     return 0;
 
 enable_lpm:
     usb_enable_lpm(udev);
     return -EBUSY;
 }
 EXPORT_SYMBOL_GPL(usb_disable_lpm);
 
 /* Grab the bandwidth_mutex before calling usb_disable_lpm() */
 int usb_unlocked_disable_lpm(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
     int ret;
 
     if (!hcd)
         return -EINVAL;
 
     mutex_lock(hcd->bandwidth_mutex);
     ret = usb_disable_lpm(udev);
     mutex_unlock(hcd->bandwidth_mutex);
 
     return ret;
 }
 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
 
 /*
  * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
  * xHCI host policy may prevent U1 or U2 from being enabled.
  *
  * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
  * until the lpm_disable_count drops to zero.  Caller must own the
  * bandwidth_mutex.
  */
 void usb_enable_lpm(struct usb_device *udev)
 {
     struct usb_hcd *hcd;
     struct usb_hub *hub;
     struct usb_port *port_dev;
 
     if (!udev || !udev->parent ||
             udev->speed < USB_SPEED_SUPER ||
             !udev->lpm_capable ||
             udev->state < USB_STATE_CONFIGURED)
         return;
 
     udev->lpm_disable_count--;
     hcd = bus_to_hcd(udev->bus);
     /* Double check that we can both enable and disable LPM.
      * Device must be configured to accept set feature U1/U2 timeout.
      */
     if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
             !hcd->driver->disable_usb3_lpm_timeout)
         return;
 
     if (udev->lpm_disable_count > 0)
         return;
 
     hub = usb_hub_to_struct_hub(udev->parent);
     if (!hub)
         return;
 
     port_dev = hub->ports[udev->portnum - 1];
 
     if (port_dev->usb3_lpm_u1_permit)
         usb_enable_link_state(hcd, udev, USB3_LPM_U1);
 
     if (port_dev->usb3_lpm_u2_permit)
         usb_enable_link_state(hcd, udev, USB3_LPM_U2);
 }
 EXPORT_SYMBOL_GPL(usb_enable_lpm);
 
 /* Grab the bandwidth_mutex before calling usb_enable_lpm() */
 void usb_unlocked_enable_lpm(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     if (!hcd)
         return;
 
     mutex_lock(hcd->bandwidth_mutex);
     usb_enable_lpm(udev);
     mutex_unlock(hcd->bandwidth_mutex);
 }
 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
 
 /* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
 static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
                       struct usb_port *port_dev)
 {
     struct usb_device *udev = port_dev->child;
     int ret;
 
     if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
         ret = hub_set_port_link_state(hub, port_dev->portnum,
                           USB_SS_PORT_LS_U0);
         if (!ret) {
             msleep(USB_RESUME_TIMEOUT);
             ret = usb_disable_remote_wakeup(udev);
         }
         if (ret)
             dev_warn(&udev->dev,
                  "Port disable: can't disable remote wake\n");
         udev->do_remote_wakeup = 0;
     }
 }
 
 #else   /* CONFIG_PM */
 
 #define hub_suspend     NULL
 #define hub_resume      NULL
 #define hub_reset_resume    NULL
 
 static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
                          struct usb_port *port_dev) { }
 
 int usb_disable_lpm(struct usb_device *udev)
 {
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_disable_lpm);
 
 void usb_enable_lpm(struct usb_device *udev) { }
 EXPORT_SYMBOL_GPL(usb_enable_lpm);
 
 int usb_unlocked_disable_lpm(struct usb_device *udev)
 {
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
 
 void usb_unlocked_enable_lpm(struct usb_device *udev) { }
 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
 
 int usb_disable_ltm(struct usb_device *udev)
 {
     return 0;
 }
 EXPORT_SYMBOL_GPL(usb_disable_ltm);
 
 void usb_enable_ltm(struct usb_device *udev) { }
 EXPORT_SYMBOL_GPL(usb_enable_ltm);
 
 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
         u16 portstatus, u16 portchange)
 {
     return 0;
 }
 
 static int usb_req_set_sel(struct usb_device *udev)
 {
     return 0;
 }
 
 #endif  /* CONFIG_PM */
 
 /*
  * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
  * a connection with a plugged-in cable but will signal the host when the cable
  * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
  */
 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 {
     struct usb_port *port_dev = hub->ports[port1 - 1];
     struct usb_device *hdev = hub->hdev;
     int ret = 0;
 
     if (!hub->error) {
         if (hub_is_superspeed(hub->hdev)) {
             hub_usb3_port_prepare_disable(hub, port_dev);
             ret = hub_set_port_link_state(hub, port_dev->portnum,
                               USB_SS_PORT_LS_U3);
         } else {
             ret = usb_clear_port_feature(hdev, port1,
                     USB_PORT_FEAT_ENABLE);
         }
     }
     if (port_dev->child && set_state)
         usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
     if (ret && ret != -ENODEV)
         dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
     return ret;
 }
 
 /*
  * usb_port_disable - disable a usb device's upstream port
  * @udev: device to disable
  * Context: @udev locked, must be able to sleep.
  *
  * Disables a USB device that isn't in active use.
  */
 int usb_port_disable(struct usb_device *udev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
 
     return hub_port_disable(hub, udev->portnum, 0);
 }
 
 /* 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.
  */
 int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
 {
     int ret;
     u16 portchange, portstatus;
     unsigned connection = 0xffff;
     int total_time, stable_time = 0;
     struct usb_port *port_dev = hub->ports[port1 - 1];
 
     for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
         ret = usb_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) {
             if (!must_be_connected ||
                  (connection == USB_PORT_STAT_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) {
             usb_clear_port_feature(hub->hdev, port1,
                     USB_PORT_FEAT_C_CONNECTION);
         }
 
         if (total_time >= HUB_DEBOUNCE_TIMEOUT)
             break;
         msleep(HUB_DEBOUNCE_STEP);
     }
 
     dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
             total_time, stable_time, portstatus);
 
     if (stable_time < HUB_DEBOUNCE_STABLE)
         return -ETIMEDOUT;
     return portstatus;
 }
 
 void usb_ep0_reinit(struct usb_device *udev)
 {
     usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
     usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
     usb_enable_endpoint(udev, &udev->ep0, true);
 }
 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
 
 #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 devnum)
 {
     int retval;
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     /*
      * The host controller will choose the device address,
      * instead of the core having chosen it earlier
      */
     if (!hcd->driver->address_device && devnum <= 1)
         return -EINVAL;
     if (udev->state == USB_STATE_ADDRESS)
         return 0;
     if (udev->state != USB_STATE_DEFAULT)
         return -EINVAL;
     if (hcd->driver->address_device)
         retval = hcd->driver->address_device(hcd, udev);
     else
         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
                 NULL, 0, USB_CTRL_SET_TIMEOUT);
     if (retval == 0) {
         update_devnum(udev, devnum);
         /* Device now using proper address. */
         usb_set_device_state(udev, USB_STATE_ADDRESS);
         usb_ep0_reinit(udev);
     }
     return retval;
 }
 
 /*
  * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
  * when they're plugged into a USB 2.0 port, but they don't work when LPM is
  * enabled.
  *
  * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
  * device says it supports the new USB 2.0 Link PM errata by setting the BESL
  * support bit in the BOS descriptor.
  */
 static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
     int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
 
     if (!udev->usb2_hw_lpm_capable || !udev->bos)
         return;
 
     if (hub)
         connect_type = hub->ports[udev->portnum - 1]->connect_type;
 
     if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
             connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
         udev->usb2_hw_lpm_allowed = 1;
         usb_enable_usb2_hardware_lpm(udev);
     }
 }
 
 static int hub_enable_device(struct usb_device *udev)
 {
     struct usb_hcd *hcd = bus_to_hcd(udev->bus);
 
     if (!hcd->driver->enable_device)
         return 0;
     if (udev->state == USB_STATE_ADDRESS)
         return 0;
     if (udev->state != USB_STATE_DEFAULT)
         return -EINVAL;
 
     return hcd->driver->enable_device(hcd, udev);
 }
 
 /* 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_and_verify_device), the caller must own the device lock and
  * the port lock.  For a newly detected device that is not accessible
  * through any global pointers, it's not necessary to lock the device,
  * but it is still necessary to lock the port.
  */
 static int
 hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
         int retry_counter)
 {
     struct usb_device   *hdev = hub->hdev;
     struct usb_hcd      *hcd = bus_to_hcd(hdev->bus);
     struct usb_port     *port_dev = hub->ports[port1 - 1];
     int         retries, operations, retval, i;
     unsigned        delay = HUB_SHORT_RESET_TIME;
     enum usb_device_speed   oldspeed = udev->speed;
     const char      *speed;
     int         devnum = udev->devnum;
     const char      *driver_name;
     bool            do_new_scheme;
 
     /* 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;
 
     /* Reset the device; full speed may morph to high speed */
     /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
     retval = hub_port_reset(hub, port1, udev, delay, false);
     if (retval < 0)     /* error or disconnect */
         goto fail;
     /* success, speed is known */
 
     retval = -ENODEV;
 
     /* Don't allow speed changes at reset, except usb 3.0 to faster */
     if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
         !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
         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.
      * For Wireless USB devices, ep0 max packet is always 512 (tho
      * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
      */
     switch (udev->speed) {
     case USB_SPEED_SUPER_PLUS:
     case USB_SPEED_SUPER:
     case USB_SPEED_WIRELESS:    /* fixed at 512 */
         udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
         break;
     case USB_SPEED_HIGH:        /* fixed at 64 */
         udev->ep0.desc.wMaxPacketSize = 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 = cpu_to_le16(64);
         break;
     case USB_SPEED_LOW:     /* fixed at 8 */
         udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
         break;
     default:
         goto fail;
     }
 
     if (udev->speed == USB_SPEED_WIRELESS)
         speed = "variable speed Wireless";
     else
         speed = usb_speed_string(udev->speed);
 
     /*
      * The controller driver may be NULL if the controller device
      * is the middle device between platform device and roothub.
      * This middle device may not need a device driver due to
      * all hardware control can be at platform device driver, this
      * platform device is usually a dual-role USB controller device.
      */
     if (udev->bus->controller->driver)
         driver_name = udev->bus->controller->driver->name;
     else
         driver_name = udev->bus->sysdev->driver->name;
 
     if (udev->speed < USB_SPEED_SUPER)
         dev_info(&udev->dev,
                 "%s %s USB device number %d using %s\n",
                 (udev->config) ? "reset" : "new", speed,
                 devnum, driver_name);
 
     /* 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) {
         if (!hub->tt.hub) {
             dev_err(&udev->dev, "parent hub has no TT\n");
             retval = -EINVAL;
             goto fail;
         }
         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.
      */
     do_new_scheme = use_new_scheme(udev, retry_counter, port_dev);
 
     for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
         if (do_new_scheme) {
             struct usb_device_descriptor *buf;
             int r = 0;
 
             retval = hub_enable_device(udev);
             if (retval < 0) {
                 dev_err(&udev->dev,
                     "hub failed to enable device, error %d\n",
                     retval);
                 goto fail;
             }
 
 #define GET_DESCRIPTOR_BUFSIZE  64
             buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
             if (!buf) {
                 retval = -ENOMEM;
                 continue;
             }
 
             /* Retry on all errors; some devices are flakey.
              * 255 is for WUSB devices, we actually need to use
              * 512 (WUSB1.0[4.8.1]).
              */
             for (operations = 0; operations < GET_MAXPACKET0_TRIES;
                     ++operations) {
                 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,
                     initial_descriptor_timeout);
                 switch (buf->bMaxPacketSize0) {
                 case 8: case 16: case 32: case 64: case 255:
                     if (buf->bDescriptorType ==
                             USB_DT_DEVICE) {
                         r = 0;
                         break;
                     }
                     fallthrough;
                 default:
                     if (r == 0)
                         r = -EPROTO;
                     break;
                 }
                 /*
                  * Some devices time out if they are powered on
                  * when already connected. They need a second
                  * reset. But only on the first attempt,
                  * lest we get into a time out/reset loop
                  */
                 if (r == 0 || (r == -ETIMEDOUT &&
                         retries == 0 &&
                         udev->speed > USB_SPEED_FULL))
                     break;
             }
             udev->descriptor.bMaxPacketSize0 =
                     buf->bMaxPacketSize0;
             kfree(buf);
 
             retval = hub_port_reset(hub, port1, udev, delay, false);
             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) {
                 if (r != -ENODEV)
                     dev_err(&udev->dev, "device descriptor read/64, error %d\n",
                             r);
                 retval = -EMSGSIZE;
                 continue;
             }
 #undef GET_DESCRIPTOR_BUFSIZE
         }
 
         /*
          * If device is WUSB, we already assigned an
          * unauthorized address in the Connect Ack sequence;
          * authorization will assign the final address.
          */
         if (udev->wusb == 0) {
             for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
                 retval = hub_set_address(udev, devnum);
                 if (retval >= 0)
                     break;
                 msleep(200);
             }
             if (retval < 0) {
                 if (retval != -ENODEV)
                     dev_err(&udev->dev, "device not accepting address %d, error %d\n",
                             devnum, retval);
                 goto fail;
             }
             if (udev->speed >= USB_SPEED_SUPER) {
                 devnum = udev->devnum;
                 dev_info(&udev->dev,
                         "%s SuperSpeed%s%s USB device number %d using %s\n",
                         (udev->config) ? "reset" : "new",
                      (udev->speed == USB_SPEED_SUPER_PLUS) ?
                             " Plus" : "",
                      (udev->ssp_rate == USB_SSP_GEN_2x2) ?
                             " Gen 2x2" :
                      (udev->ssp_rate == USB_SSP_GEN_2x1) ?
                             " Gen 2x1" :
                      (udev->ssp_rate == USB_SSP_GEN_1x2) ?
                             " Gen 1x2" : "",
                      devnum, driver_name);
             }
 
             /* 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 (do_new_scheme)
                 break;
         }
 
         retval = usb_get_device_descriptor(udev, 8);
         if (retval < 8) {
             if (retval != -ENODEV)
                 dev_err(&udev->dev,
                     "device descriptor read/8, error %d\n",
                     retval);
             if (retval >= 0)
                 retval = -EMSGSIZE;
         } else {
             u32 delay;
 
             retval = 0;
 
             delay = udev->parent->hub_delay;
             udev->hub_delay = min_t(u32, delay,
                         USB_TP_TRANSMISSION_DELAY_MAX);
             retval = usb_set_isoch_delay(udev);
             if (retval) {
                 dev_dbg(&udev->dev,
                     "Failed set isoch delay, error %d\n",
                     retval);
                 retval = 0;
             }
             break;
         }
     }
     if (retval)
         goto fail;
 
     /*
      * Some superspeed devices have finished the link training process
      * and attached to a superspeed hub port, but the device descriptor
      * got from those devices show they aren't superspeed devices. Warm
      * reset the port attached by the devices can fix them.
      */
     if ((udev->speed >= USB_SPEED_SUPER) &&
             (le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
         dev_err(&udev->dev, "got a wrong device descriptor, "
                 "warm reset device\n");
         hub_port_reset(hub, port1, udev,
                 HUB_BH_RESET_TIME, true);
         retval = -EINVAL;
         goto fail;
     }
 
     if (udev->descriptor.bMaxPacketSize0 == 0xff ||
             udev->speed >= USB_SPEED_SUPER)
         i = 512;
     else
         i = udev->descriptor.bMaxPacketSize0;
     if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
         if (udev->speed == USB_SPEED_LOW ||
                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
             dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
             retval = -EMSGSIZE;
             goto fail;
         }
         if (udev->speed == USB_SPEED_FULL)
             dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
         else
             dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
         udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
         usb_ep0_reinit(udev);
     }
 
     retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
     if (retval < (signed)sizeof(udev->descriptor)) {
         if (retval != -ENODEV)
             dev_err(&udev->dev, "device descriptor read/all, error %d\n",
                     retval);
         if (retval >= 0)
             retval = -ENOMSG;
         goto fail;
     }
 
     usb_detect_quirks(udev);
 
     if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
         retval = usb_get_bos_descriptor(udev);
         if (!retval) {
             udev->lpm_capable = usb_device_supports_lpm(udev);
             udev->lpm_disable_count = 1;
             usb_set_lpm_parameters(udev);
             usb_req_set_sel(udev);
         }
     }
 
     retval = 0;
     /* notify HCD that we have a device connected and addressed */
     if (hcd->driver->update_device)
         hcd->driver->update_device(hcd, udev);
     hub_set_initial_usb2_lpm_policy(udev);
 fail:
     if (retval) {
         hub_port_disable(hub, port1, 0);
         update_devnum(udev, devnum);    /* for disconnect processing */
     }
     return retval;
 }
 
 static void
 check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
 {
     struct usb_qualifier_descriptor *qual;
     int             status;
 
     if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
         return;
 
     qual = kmalloc(sizeof *qual, GFP_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;
             queue_delayed_work(system_power_efficient_wq,
                     &hub->leds, 0);
         }
     }
     kfree(qual);
 }
 
 static unsigned
 hub_power_remaining(struct usb_hub *hub)
 {
     struct usb_device *hdev = hub->hdev;
     int remaining;
     int port1;
 
     if (!hub->limited_power)
         return 0;
 
     remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
     for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
         struct usb_port *port_dev = hub->ports[port1 - 1];
         struct usb_device *udev = port_dev->child;
         unsigned unit_load;
         int delta;
 
         if (!udev)
             continue;
         if (hub_is_superspeed(udev))
             unit_load = 150;
         else
             unit_load = 100;
 
         /*
          * Unconfigured devices may not use more than one unit load,
          * or 8mA for OTG ports
          */
         if (udev->actconfig)
             delta = usb_get_max_power(udev, udev->actconfig);
         else if (port1 != udev->bus->otg_port || hdev->parent)
             delta = unit_load;
         else
             delta = 8;
         if (delta > hub->mA_per_port)
             dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
                     delta, hub->mA_per_port);
         remaining -= delta;
     }
     if (remaining < 0) {
         dev_warn(hub->intfdev, "%dmA over power budget!\n",
             -remaining);
         remaining = 0;
     }
     return remaining;
 }
 
 
 static int descriptors_changed(struct usb_device *udev,
         struct usb_device_descriptor *old_device_descriptor,
         struct usb_host_bos *old_bos)
 {
     int     changed = 0;
     unsigned    index;
     unsigned    serial_len = 0;
     unsigned    len;
     unsigned    old_length;
     int     length;
     char        *buf;
 
     if (memcmp(&udev->descriptor, old_device_descriptor,
             sizeof(*old_device_descriptor)) != 0)
         return 1;
 
     if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
         return 1;
     if (udev->bos) {
         len = le16_to_cpu(udev->bos->desc->wTotalLength);
         if (len != le16_to_cpu(old_bos->desc->wTotalLength))
             return 1;
         if (memcmp(udev->bos->desc, old_bos->desc, len))
             return 1;
     }
 
     /* Since the idVendor, idProduct, and bcdDevice values in the
      * device descriptor haven't changed, we will assume the
      * Manufacturer and Product strings haven't changed either.
      * But the SerialNumber string could be different (e.g., a
      * different flash card of the same brand).
      */
     if (udev->serial)
         serial_len = strlen(udev->serial) + 1;
 
     len = serial_len;
     for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
         old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
         len = max(len, old_length);
     }
 
     buf = kmalloc(len, GFP_NOIO);
     if (!buf)
         /* assume the worst */
         return 1;
 
     for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
         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);
             changed = 1;
             break;
         }
         if (memcmp(buf, udev->rawdescriptors[index], old_length)
                 != 0) {
             dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
                 index,
                 ((struct usb_config_descriptor *) buf)->
                     bConfigurationValue);
             changed = 1;
             break;
         }
     }
 
     if (!changed && serial_len) {
         length = usb_string(udev, udev->descriptor.iSerialNumber,
                 buf, serial_len);
         if (length + 1 != serial_len) {
             dev_dbg(&udev->dev, "serial string error %d\n",
                     length);
             changed = 1;
         } else if (memcmp(buf, udev->serial, length) != 0) {
             dev_dbg(&udev->dev, "serial string changed\n");
             changed = 1;
         }
     }
 
     kfree(buf);
     return changed;
 }
 
 static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
         u16 portchange)
 {
     int status = -ENODEV;
     int i;
     unsigned unit_load;
     struct usb_device *hdev = hub->hdev;
     struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
     struct usb_port *port_dev = hub->ports[port1 - 1];
     struct usb_device *udev = port_dev->child;
     static int unreliable_port = -1;
     bool retry_locked;
 
     /* Disconnect any existing devices under this port */
     if (udev) {
         if (hcd->usb_phy && !hdev->parent)
             usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
         usb_disconnect(&port_dev->child);
     }
 
     /* We can forget about a "removed" device when there's a physical
      * disconnect or the connect status changes.
      */
     if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
             (portchange & USB_PORT_STAT_C_CONNECTION))
         clear_bit(port1, hub->removed_bits);
 
     if (portchange & (USB_PORT_STAT_C_CONNECTION |
                 USB_PORT_STAT_C_ENABLE)) {
         status = hub_port_debounce_be_stable(hub, port1);
         if (status < 0) {
             if (status != -ENODEV &&
                 port1 != unreliable_port &&
                 printk_ratelimit())
                 dev_err(&port_dev->dev, "connect-debounce failed\n");
             portstatus &= ~USB_PORT_STAT_CONNECTION;
             unreliable_port = port1;
         } else {
             portstatus = status;
         }
     }
 
     /* Return now if debouncing failed or nothing is connected or
      * the device was "removed".
      */
     if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
             test_bit(port1, hub->removed_bits)) {
 
         /*
          * maybe switch power back on (e.g. root hub was reset)
          * but only if the port isn't owned by someone else.
          */
         if (hub_is_port_power_switchable(hub)
                 && !usb_port_is_power_on(hub, portstatus)
                 && !port_dev->port_owner)
             set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 
         if (portstatus & USB_PORT_STAT_ENABLE)
             goto done;
         return;
     }
     if (hub_is_superspeed(hub->hdev))
         unit_load = 150;
     else
         unit_load = 100;
 
     status = 0;
 
     for (i = 0; i < PORT_INIT_TRIES; i++) {
         usb_lock_port(port_dev);
         mutex_lock(hcd->address0_mutex);
         retry_locked = true;
         /* 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(&port_dev->dev,
                     "couldn't allocate usb_device\n");
             mutex_unlock(hcd->address0_mutex);
             usb_unlock_port(port_dev);
             goto done;
         }
 
         usb_set_device_state(udev, USB_STATE_POWERED);
         udev->bus_mA = hub->mA_per_port;
         udev->level = hdev->level + 1;
         udev->wusb = hub_is_wusb(hub);
 
         /* Devices connected to SuperSpeed hubs are USB 3.0 or later */
         if (hub_is_superspeed(hub->hdev))
             udev->speed = USB_SPEED_SUPER;
         else
             udev->speed = USB_SPEED_UNKNOWN;
 
         choose_devnum(udev);
         if (udev->devnum <= 0) {
             status = -ENOTCONN; /* Don't retry */
             goto loop;
         }
 
         /* reset (non-USB 3.0 devices) and get descriptor */
         status = hub_port_init(hub, udev, port1, i);
         if (status < 0)
             goto loop;
 
         mutex_unlock(hcd->address0_mutex);
         usb_unlock_port(port_dev);
         retry_locked = false;
 
         if (udev->quirks & USB_QUIRK_DELAY_INIT)
             msleep(2000);
 
         /* 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
                 && udev->bus_mA <= unit_load) {
             u16 devstat;
 
             status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
                     &devstat);
             if (status) {
                 dev_dbg(&udev->dev, "get status %d ?\n", status);
                 goto loop_disable;
             }
             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;
                     queue_delayed_work(
                         system_power_efficient_wq,
                         &hub->leds, 0);
                 }
                 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.
          */
         status = 0;
 
         mutex_lock(&usb_port_peer_mutex);
 
         /* 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
             port_dev->child = udev;
         spin_unlock_irq(&device_state_lock);
         mutex_unlock(&usb_port_peer_mutex);
 
         /* Run it through the hoops (find a driver, etc) */
         if (!status) {
             status = usb_new_device(udev);
             if (status) {
                 mutex_lock(&usb_port_peer_mutex);
                 spin_lock_irq(&device_state_lock);
                 port_dev->child = NULL;
                 spin_unlock_irq(&device_state_lock);
                 mutex_unlock(&usb_port_peer_mutex);
             } else {
                 if (hcd->usb_phy && !hdev->parent)
                     usb_phy_notify_connect(hcd->usb_phy,
                             udev->speed);
             }
         }
 
         if (status)
             goto loop_disable;
 
         status = hub_power_remaining(hub);
         if (status)
             dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
 
         return;
 
 loop_disable:
         hub_port_disable(hub, port1, 1);
 loop:
         usb_ep0_reinit(udev);
         release_devnum(udev);
         hub_free_dev(udev);
         if (retry_locked) {
             mutex_unlock(hcd->address0_mutex);
             usb_unlock_port(port_dev);
         }
         usb_put_dev(udev);
         if ((status == -ENOTCONN) || (status == -ENOTSUPP))
             break;
 
         /* When halfway through our retry count, power-cycle the port */
         if (i == (PORT_INIT_TRIES - 1) / 2) {
             dev_info(&port_dev->dev, "attempt power cycle\n");
             usb_hub_set_port_power(hdev, hub, port1, false);
             msleep(2 * hub_power_on_good_delay(hub));
             usb_hub_set_port_power(hdev, hub, port1, true);
             msleep(hub_power_on_good_delay(hub));
         }
     }
     if (hub->hdev->parent ||
             !hcd->driver->port_handed_over ||
             !(hcd->driver->port_handed_over)(hcd, port1)) {
         if (status != -ENOTCONN && status != -ENODEV)
             dev_err(&port_dev->dev,
                     "unable to enumerate USB device\n");
     }
 
 done:
     hub_port_disable(hub, port1, 1);
     if (hcd->driver->relinquish_port && !hub->hdev->parent) {
         if (status != -ENOTCONN && status != -ENODEV)
             hcd->driver->relinquish_port(hcd, port1);
     }
 }
 
 /* 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_and_verify_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)
         __must_hold(&port_dev->status_lock)
 {
     struct usb_port *port_dev = hub->ports[port1 - 1];
     struct usb_device *udev = port_dev->child;
     struct usb_device_descriptor descriptor;
     int status = -ENODEV;
     int retval;
 
     dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
             portchange, portspeed(hub, portstatus));
 
     if (hub->has_indicators) {
         set_port_led(hub, port1, HUB_LED_AUTO);
         hub->indicator[port1-1] = INDICATOR_AUTO;
     }
 
 #ifdef  CONFIG_USB_OTG
     /* during HNP, don't repeat the debounce */
     if (hub->hdev->bus->is_b_host)
         portchange &= ~(USB_PORT_STAT_C_CONNECTION |
                 USB_PORT_STAT_C_ENABLE);
 #endif
 
     /* Try to resuscitate an existing device */
     if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
             udev->state != USB_STATE_NOTATTACHED) {
         if (portstatus & USB_PORT_STAT_ENABLE) {
             /*
              * USB-3 connections are initialized automatically by
              * the hostcontroller hardware. Therefore check for
              * changed device descriptors before resuscitating the
              * device.
              */
             descriptor = udev->descriptor;
             retval = usb_get_device_descriptor(udev,
                     sizeof(udev->descriptor));
             if (retval < 0) {
                 dev_dbg(&udev->dev,
                         "can't read device descriptor %d\n",
                         retval);
             } else {
                 if (descriptors_changed(udev, &descriptor,
                         udev->bos)) {
                     dev_dbg(&udev->dev,
                             "device descriptor has changed\n");
                     /* for disconnect() calls */
                     udev->descriptor = descriptor;
                 } else {
                     status = 0; /* Nothing to do */
                 }
             }
 #ifdef CONFIG_PM
         } else if (udev->state == USB_STATE_SUSPENDED &&
                 udev->persist_enabled) {
             /* For a suspended device, treat this as a
              * remote wakeup event.
              */
             usb_unlock_port(port_dev);
             status = usb_remote_wakeup(udev);
             usb_lock_port(port_dev);
 #endif
         } else {
             /* Don't resuscitate */;
         }
     }
     clear_bit(port1, hub->change_bits);
 
     /* successfully revalidated the connection */
     if (status == 0)
         return;
 
     usb_unlock_port(port_dev);
     hub_port_connect(hub, port1, portstatus, portchange);
     usb_lock_port(port_dev);
 }
 
 /* Handle notifying userspace about hub over-current events */
 static void port_over_current_notify(struct usb_port *port_dev)
 {
     char *envp[3] = { NULL, NULL, NULL };
     struct device *hub_dev;
     char *port_dev_path;
 
     sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
 
     hub_dev = port_dev->dev.parent;
 
     if (!hub_dev)
         return;
 
     port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
     if (!port_dev_path)
         return;
 
     envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
     if (!envp[0])
         goto exit;
 
     envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
             port_dev->over_current_count);
     if (!envp[1])
         goto exit;
 
     kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
 
 exit:
     kfree(envp[1]);
     kfree(envp[0]);
     kfree(port_dev_path);
 }
 
 static void port_event(struct usb_hub *hub, int port1)
         __must_hold(&port_dev->status_lock)
 {
     int connect_change;
     struct usb_port *port_dev = hub->ports[port1 - 1];
     struct usb_device *udev = port_dev->child;
     struct usb_device *hdev = hub->hdev;
     u16 portstatus, portchange;
     int i = 0;
 
     connect_change = test_bit(port1, hub->change_bits);
     clear_bit(port1, hub->event_bits);
     clear_bit(port1, hub->wakeup_bits);
 
     if (usb_hub_port_status(hub, port1, &portstatus, &portchange) < 0)
         return;
 
     if (portchange & USB_PORT_STAT_C_CONNECTION) {
         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
         connect_change = 1;
     }
 
     if (portchange & USB_PORT_STAT_C_ENABLE) {
         if (!connect_change)
             dev_dbg(&port_dev->dev, "enable change, status %08x\n",
                     portstatus);
         usb_clear_port_feature(hdev, port1, 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 && udev) {
             dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
             connect_change = 1;
         }
     }
 
     if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
         u16 status = 0, unused;
         port_dev->over_current_count++;
         port_over_current_notify(port_dev);
 
         dev_dbg(&port_dev->dev, "over-current change #%u\n",
             port_dev->over_current_count);
         usb_clear_port_feature(hdev, port1,
                 USB_PORT_FEAT_C_OVER_CURRENT);
         msleep(100);    /* Cool down */
         hub_power_on(hub, true);
         usb_hub_port_status(hub, port1, &status, &unused);
         if (status & USB_PORT_STAT_OVERCURRENT)
             dev_err(&port_dev->dev, "over-current condition\n");
     }
 
     if (portchange & USB_PORT_STAT_C_RESET) {
         dev_dbg(&port_dev->dev, "reset change\n");
         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
     }
     if ((portchange & USB_PORT_STAT_C_BH_RESET)
         && hub_is_superspeed(hdev)) {
         dev_dbg(&port_dev->dev, "warm reset change\n");
         usb_clear_port_feature(hdev, port1,
                 USB_PORT_FEAT_C_BH_PORT_RESET);
     }
     if (portchange & USB_PORT_STAT_C_LINK_STATE) {
         dev_dbg(&port_dev->dev, "link state change\n");
         usb_clear_port_feature(hdev, port1,
                 USB_PORT_FEAT_C_PORT_LINK_STATE);
     }
     if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
         dev_warn(&port_dev->dev, "config error\n");
         usb_clear_port_feature(hdev, port1,
                 USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
     }
 
     /* skip port actions that require the port to be powered on */
     if (!pm_runtime_active(&port_dev->dev))
         return;
 
     if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
         connect_change = 1;
 
     /*
      * Avoid trying to recover a USB3 SS.Inactive port with a warm reset if
      * the device was disconnected. A 12ms disconnect detect timer in
      * SS.Inactive state transitions the port to RxDetect automatically.
      * SS.Inactive link error state is common during device disconnect.
      */
     while (hub_port_warm_reset_required(hub, port1, portstatus)) {
         if ((i++ < DETECT_DISCONNECT_TRIES) && udev) {
             u16 unused;
 
             msleep(20);
             usb_hub_port_status(hub, port1, &portstatus, &unused);
             dev_dbg(&port_dev->dev, "Wait for inactive link disconnect detect\n");
             continue;
         } else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
                 || udev->state == USB_STATE_NOTATTACHED) {
             dev_dbg(&port_dev->dev, "do warm reset, port only\n");
             if (hub_port_reset(hub, port1, NULL,
                     HUB_BH_RESET_TIME, true) < 0)
                 hub_port_disable(hub, port1, 1);
         } else {
             dev_dbg(&port_dev->dev, "do warm reset, full device\n");
             usb_unlock_port(port_dev);
             usb_lock_device(udev);
             usb_reset_device(udev);
             usb_unlock_device(udev);
             usb_lock_port(port_dev);
             connect_change = 0;
         }
         break;
     }
 
     if (connect_change)
         hub_port_connect_change(hub, port1, portstatus, portchange);
 }
 
 static void hub_event(struct work_struct *work)
 {
     struct usb_device *hdev;
     struct usb_interface *intf;
     struct usb_hub *hub;
     struct device *hub_dev;
     u16 hubstatus;
     u16 hubchange;
     int i, ret;
 
     hub = container_of(work, struct usb_hub, events);
     hdev = hub->hdev;
     hub_dev = hub->intfdev;
     intf = to_usb_interface(hub_dev);
 
     kcov_remote_start_usb((u64)hdev->bus->busnum);
 
     dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
             hdev->state, hdev->maxchild,
             /* 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. */
     usb_lock_device(hdev);
     if (unlikely(hub->disconnected))
         goto out_hdev_lock;
 
     /* If the hub has died, clean up after it */
     if (hdev->state == USB_STATE_NOTATTACHED) {
         hub->error = -ENODEV;
         hub_quiesce(hub, HUB_DISCONNECT);
         goto out_hdev_lock;
     }
 
     /* Autoresume */
     ret = usb_autopm_get_interface(intf);
     if (ret) {
         dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
         goto out_hdev_lock;
     }
 
     /* If this is an inactive hub, do nothing */
     if (hub->quiescing)
         goto out_autopm;
 
     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 out_autopm;
         }
 
         hub->nerrors = 0;
         hub->error = 0;
     }
 
     /* deal with port status changes */
     for (i = 1; i <= hdev->maxchild; i++) {
         struct usb_port *port_dev = hub->ports[i - 1];
 
         if (test_bit(i, hub->event_bits)
                 || test_bit(i, hub->change_bits)
                 || test_bit(i, hub->wakeup_bits)) {
             /*
              * The get_noresume and barrier ensure that if
              * the port was in the process of resuming, we
              * flush that work and keep the port active for
              * the duration of the port_event().  However,
              * if the port is runtime pm suspended
              * (powered-off), we leave it in that state, run
              * an abbreviated port_event(), and move on.
              */
             pm_runtime_get_noresume(&port_dev->dev);
             pm_runtime_barrier(&port_dev->dev);
             usb_lock_port(port_dev);
             port_event(hub, i);
             usb_unlock_port(port_dev);
             pm_runtime_put_sync(&port_dev->dev);
         }
     }
 
     /* 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 (hubstatus & HUB_STATUS_LOCAL_POWER)
                 /* FIXME: Is this always true? */
                 hub->limited_power = 1;
             else
                 hub->limited_power = 0;
         }
         if (hubchange & HUB_CHANGE_OVERCURRENT) {
             u16 status = 0;
             u16 unused;
 
             dev_dbg(hub_dev, "over-current change\n");
             clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
             msleep(500);    /* Cool down */
             hub_power_on(hub, true);
             hub_hub_status(hub, &status, &unused);
             if (status & HUB_STATUS_OVERCURRENT)
                 dev_err(hub_dev, "over-current condition\n");
         }
     }
 
 out_autopm:
     /* Balance the usb_autopm_get_interface() above */
     usb_autopm_put_interface_no_suspend(intf);
 out_hdev_lock:
     usb_unlock_device(hdev);
 
     /* Balance the stuff in kick_hub_wq() and allow autosuspend */
     usb_autopm_put_interface(intf);
     kref_put(&hub->kref, hub_release);
 
     kcov_remote_stop();
 }
 
 static const struct usb_device_id hub_id_table[] = {
     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
                    | USB_DEVICE_ID_MATCH_PRODUCT
                    | USB_DEVICE_ID_MATCH_INT_CLASS,
       .idVendor = USB_VENDOR_SMSC,
       .idProduct = USB_PRODUCT_USB5534B,
       .bInterfaceClass = USB_CLASS_HUB,
       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
                    | USB_DEVICE_ID_MATCH_PRODUCT,
       .idVendor = USB_VENDOR_CYPRESS,
       .idProduct = USB_PRODUCT_CY7C65632,
       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
             | USB_DEVICE_ID_MATCH_INT_CLASS,
       .idVendor = USB_VENDOR_GENESYS_LOGIC,
       .bInterfaceClass = USB_CLASS_HUB,
       .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
     { .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 = {
     .name =     "hub",
     .probe =    hub_probe,
     .disconnect =   hub_disconnect,
     .suspend =  hub_suspend,
     .resume =   hub_resume,
     .reset_resume = hub_reset_resume,
     .pre_reset =    hub_pre_reset,
     .post_reset =   hub_post_reset,
     .unlocked_ioctl = hub_ioctl,
     .id_table = hub_id_table,
     .supports_autosuspend = 1,
 };
 
 int usb_hub_init(void)
 {
     if (usb_register(&hub_driver) < 0) {
         printk(KERN_ERR "%s: can't register hub driver\n",
             usbcore_name);
         return -1;
     }
 
     /*
      * The workqueue needs to be freezable to avoid interfering with
      * USB-PERSIST port handover. Otherwise it might see that a full-speed
      * device was gone before the EHCI controller had handed its port
      * over to the companion full-speed controller.
      */
     hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
     if (hub_wq)
         return 0;
 
     /* Fall through if kernel_thread failed */
     usb_deregister(&hub_driver);
     pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
 
     return -1;
 }
 
 void usb_hub_cleanup(void)
 {
     destroy_workqueue(hub_wq);
 
     /*
      * 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() */
 
 /**
  * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
  *
  * WARNING - don't use this routine to reset a composite device
  * (one with multiple interfaces owned by separate drivers)!
  * Use usb_reset_device() instead.
  *
  * 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 hub_wq 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.
  *
  * Return: 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.
  *
  * Note:
  * The caller must own the device lock and the port lock, the latter is
  * taken by usb_reset_device().  For example, it's safe to use
  * usb_reset_device() 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().
  *
  * Locking exception: This routine may also be called from within an
  * autoresume handler.  Such usage won't conflict with other tasks
  * holding the device lock because these tasks should always call
  * usb_autopm_resume_device(), thereby preventing any unwanted
  * autoresume.  The autoresume handler is expected to have already
  * acquired the port lock before calling this routine.
  */
 static int usb_reset_and_verify_device(struct usb_device *udev)
 {
     struct usb_device       *parent_hdev = udev->parent;
     struct usb_hub          *parent_hub;
     struct usb_hcd          *hcd = bus_to_hcd(udev->bus);
     struct usb_device_descriptor    descriptor = udev->descriptor;
     struct usb_host_bos     *bos;
     int             i, j, ret = 0;
     int             port1 = udev->portnum;
 
     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)
         return -EISDIR;
 
     parent_hub = usb_hub_to_struct_hub(parent_hdev);
 
     /* Disable USB2 hardware LPM.
      * It will be re-enabled by the enumeration process.
      */
     usb_disable_usb2_hardware_lpm(udev);
 
     bos = udev->bos;
     udev->bos = NULL;
 
     mutex_lock(hcd->address0_mutex);
 
     for (i = 0; i < PORT_INIT_TRIES; ++i) {
 
         /* ep0 maxpacket size may change; let the HCD know about it.
          * Other endpoints will be handled by re-enumeration. */
         usb_ep0_reinit(udev);
         ret = hub_port_init(parent_hub, udev, port1, i);
         if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
             break;
     }
     mutex_unlock(hcd->address0_mutex);
 
     if (ret < 0)
         goto re_enumerate;
 
     /* Device might have changed firmware (DFU or similar) */
     if (descriptors_changed(udev, &descriptor, bos)) {
         dev_info(&udev->dev, "device firmware changed\n");
         udev->descriptor = descriptor;  /* for disconnect() calls */
         goto re_enumerate;
     }
 
     /* Restore the device's previous configuration */
     if (!udev->actconfig)
         goto done;
 
     mutex_lock(hcd->bandwidth_mutex);
     ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
     if (ret < 0) {
         dev_warn(&udev->dev,
                 "Busted HC?  Not enough HCD resources for "
                 "old configuration.\n");
         mutex_unlock(hcd->bandwidth_mutex);
         goto re_enumerate;
     }
     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);
         mutex_unlock(hcd->bandwidth_mutex);
         goto re_enumerate;
     }
     mutex_unlock(hcd->bandwidth_mutex);
     usb_set_device_state(udev, USB_STATE_CONFIGURED);
 
     /* Put interfaces back into the same altsettings as before.
      * Don't bother to send the Set-Interface request for interfaces
      * that were already in altsetting 0; besides being unnecessary,
      * many devices can't handle it.  Instead just reset the host-side
      * endpoint state.
      */
     for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
         struct usb_host_config *config = udev->actconfig;
         struct usb_interface *intf = config->interface[i];
         struct usb_interface_descriptor *desc;
 
         desc = &intf->cur_altsetting->desc;
         if (desc->bAlternateSetting == 0) {
             usb_disable_interface(udev, intf, true);
             usb_enable_interface(udev, intf, true);
             ret = 0;
         } else {
             /* Let the bandwidth allocation function know that this
              * device has been reset, and it will have to use
              * alternate setting 0 as the current alternate setting.
              */
             intf->resetting_device = 1;
             ret = usb_set_interface(udev, desc->bInterfaceNumber,
                     desc->bAlternateSetting);
             intf->resetting_device = 0;
         }
         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;
         }
         /* Resetting also frees any allocated streams */
         for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
             intf->cur_altsetting->endpoint[j].streams = 0;
     }
 
 done:
     /* Now that the alt settings are re-installed, enable LTM and LPM. */
     usb_enable_usb2_hardware_lpm(udev);
     usb_unlocked_enable_lpm(udev);
     usb_enable_ltm(udev);
     usb_release_bos_descriptor(udev);
     udev->bos = bos;
     return 0;
 
 re_enumerate:
     usb_release_bos_descriptor(udev);
     udev->bos = bos;
     hub_port_logical_disconnect(parent_hub, port1);
     return -ENODEV;
 }
 
 /**
  * usb_reset_device - warn interface drivers and perform a USB port reset
  * @udev: device to reset (not in NOTATTACHED state)
  *
  * Warns all drivers bound to registered interfaces (using their pre_reset
  * method), performs the port reset, and then lets the drivers know that
  * the reset is over (using their post_reset method).
  *
  * Return: The same as for usb_reset_and_verify_device().
  * However, if a reset is already in progress (for instance, if a
  * driver doesn't have pre_reset() or post_reset() callbacks, and while
  * being unbound or re-bound during the ongoing reset its disconnect()
  * or probe() routine tries to perform a second, nested reset), the
  * routine returns -EINPROGRESS.
  *
  * Note:
  * 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().
  *
  * If an interface is currently being probed or disconnected, we assume
  * its driver knows how to handle resets.  For all other interfaces,
  * if the driver doesn't have pre_reset and post_reset methods then
  * we attempt to unbind it and rebind afterward.
  */
 int usb_reset_device(struct usb_device *udev)
 {
     int ret;
     int i;
     unsigned int noio_flag;
     struct usb_port *port_dev;
     struct usb_host_config *config = udev->actconfig;
     struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
 
     if (udev->state == USB_STATE_NOTATTACHED) {
         dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
                 udev->state);
         return -EINVAL;
     }
 
     if (!udev->parent) {
         /* this requires hcd-specific logic; see ohci_restart() */
         dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
         return -EISDIR;
     }
 
     if (udev->reset_in_progress)
         return -EINPROGRESS;
     udev->reset_in_progress = 1;
 
     port_dev = hub->ports[udev->portnum - 1];
 
     /*
      * Don't allocate memory with GFP_KERNEL in current
      * context to avoid possible deadlock if usb mass
      * storage interface or usbnet interface(iSCSI case)
      * is included in current configuration. The easist
      * approach is to do it for every device reset,
      * because the device 'memalloc_noio' flag may have
      * not been set before reseting the usb device.
      */
     noio_flag = memalloc_noio_save();
 
     /* Prevent autosuspend during the reset */
     usb_autoresume_device(udev);
 
     if (config) {
         for (i = 0; i < config->desc.bNumInterfaces; ++i) {
             struct usb_interface *cintf = config->interface[i];
             struct usb_driver *drv;
             int unbind = 0;
 
             if (cintf->dev.driver) {
                 drv = to_usb_driver(cintf->dev.driver);
                 if (drv->pre_reset && drv->post_reset)
                     unbind = (drv->pre_reset)(cintf);
                 else if (cintf->condition ==
                         USB_INTERFACE_BOUND)
                     unbind = 1;
                 if (unbind)
                     usb_forced_unbind_intf(cintf);
             }
         }
     }
 
     usb_lock_port(port_dev);
     ret = usb_reset_and_verify_device(udev);
     usb_unlock_port(port_dev);
 
     if (config) {
         for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
             struct usb_interface *cintf = config->interface[i];
             struct usb_driver *drv;
             int rebind = cintf->needs_binding;
 
             if (!rebind && cintf->dev.driver) {
                 drv = to_usb_driver(cintf->dev.driver);
                 if (drv->post_reset)
                     rebind = (drv->post_reset)(cintf);
                 else if (cintf->condition ==
                         USB_INTERFACE_BOUND)
                     rebind = 1;
                 if (rebind)
                     cintf->needs_binding = 1;
             }
         }
 
         /* If the reset failed, hub_wq will unbind drivers later */
         if (ret == 0)
             usb_unbind_and_rebind_marked_interfaces(udev);
     }
 
     usb_autosuspend_device(udev);
     memalloc_noio_restore(noio_flag);
     udev->reset_in_progress = 0;
     return ret;
 }
 EXPORT_SYMBOL_GPL(usb_reset_device);
 
 
 /**
  * usb_queue_reset_device - Reset a USB device from an atomic context
  * @iface: USB interface belonging to the device to reset
  *
  * This function can be used to reset a USB device from an atomic
  * context, where usb_reset_device() won't work (as it blocks).
  *
  * Doing a reset via this method is functionally equivalent to calling
  * usb_reset_device(), except for the fact that it is delayed to a
  * workqueue. This means that any drivers bound to other interfaces
  * might be unbound, as well as users from usbfs in user space.
  *
  * Corner cases:
  *
  * - Scheduling two resets at the same time from two different drivers
  *   attached to two different interfaces of the same device is
  *   possible; depending on how the driver attached to each interface
  *   handles ->pre_reset(), the second reset might happen or not.
  *
  * - If the reset is delayed so long that the interface is unbound from
  *   its driver, the reset will be skipped.
  *
  * - This function can be called during .probe().  It can also be called
  *   during .disconnect(), but doing so is pointless because the reset
  *   will not occur.  If you really want to reset the device during
  *   .disconnect(), call usb_reset_device() directly -- but watch out
  *   for nested unbinding issues!
  */
 void usb_queue_reset_device(struct usb_interface *iface)
 {
     if (schedule_work(&iface->reset_ws))
         usb_get_intf(iface);
 }
 EXPORT_SYMBOL_GPL(usb_queue_reset_device);
 
 /**
  * usb_hub_find_child - Get the pointer of child device
  * attached to the port which is specified by @port1.
  * @hdev: USB device belonging to the usb hub
  * @port1: port num to indicate which port the child device
  *  is attached to.
  *
  * USB drivers call this function to get hub's child device
  * pointer.
  *
  * Return: %NULL if input param is invalid and
  * child's usb_device pointer if non-NULL.
  */
 struct usb_device *usb_hub_find_child(struct usb_device *hdev,
         int port1)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 
     if (port1 < 1 || port1 > hdev->maxchild)
         return NULL;
     return hub->ports[port1 - 1]->child;
 }
 EXPORT_SYMBOL_GPL(usb_hub_find_child);
 
 void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
         struct usb_hub_descriptor *desc)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
     enum usb_port_connect_type connect_type;
     int i;
 
     if (!hub)
         return;
 
     if (!hub_is_superspeed(hdev)) {
         for (i = 1; i <= hdev->maxchild; i++) {
             struct usb_port *port_dev = hub->ports[i - 1];
 
             connect_type = port_dev->connect_type;
             if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
                 u8 mask = 1 << (i%8);
 
                 if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
                     dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
                     desc->u.hs.DeviceRemovable[i/8] |= mask;
                 }
             }
         }
     } else {
         u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
 
         for (i = 1; i <= hdev->maxchild; i++) {
             struct usb_port *port_dev = hub->ports[i - 1];
 
             connect_type = port_dev->connect_type;
             if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
                 u16 mask = 1 << i;
 
                 if (!(port_removable & mask)) {
                     dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
                     port_removable |= mask;
                 }
             }
         }
 
         desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
     }
 }
 
 #ifdef CONFIG_ACPI
 /**
  * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
  * @hdev: USB device belonging to the usb hub
  * @port1: port num of the port
  *
  * Return: Port's acpi handle if successful, %NULL if params are
  * invalid.
  */
 acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
     int port1)
 {
     struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 
     if (!hub)
         return NULL;
 
     return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
 }
 #endif