diff --git a/README.rst b/README.rst
index 5b994c35..1a96f6e1 100644
--- a/README.rst
+++ b/README.rst
@@ -82,7 +82,7 @@ Host Stack
 
 - Human Interface Device (HID): Keyboard, Mouse, Generic
 - Mass Storage Class (MSC)
-- Hub currently only supports 1 level of hub (due to my laziness)
+- Hub with multiple-level support
 
 OS Abstraction layer
 ====================
diff --git a/examples/host/cdc_msc_hid/src/tusb_config.h b/examples/host/cdc_msc_hid/src/tusb_config.h
index 76d96b55..33f34315 100644
--- a/examples/host/cdc_msc_hid/src/tusb_config.h
+++ b/examples/host/cdc_msc_hid/src/tusb_config.h
@@ -89,7 +89,7 @@
 // Size of buffer to hold descriptors and other data used for enumeration
 #define CFG_TUH_ENUMERATION_BUFSIZE 256
 
-#define CFG_TUH_HUB                 1
+#define CFG_TUH_HUB                 1 // number of supported hubs
 #define CFG_TUH_CDC                 1
 #define CFG_TUH_HID                 4 // typical keyboard + mouse device can have 3-4 HID interfaces
 #define CFG_TUH_MSC                 1
diff --git a/src/host/hcd.h b/src/host/hcd.h
index 2bc85034..deebc59d 100644
--- a/src/host/hcd.h
+++ b/src/host/hcd.h
@@ -207,13 +207,11 @@ void hcd_event_xfer_complete(uint8_t dev_addr, uint8_t ep_addr, uint32_t xferred
     .rhport   = 0, // TODO correct rhport
     .event_id = HCD_EVENT_XFER_COMPLETE,
     .dev_addr = dev_addr,
-    .xfer_complete =
-    {
-      .ep_addr = ep_addr,
-      .result  = result,
-      .len     = xferred_bytes
-    }
   };
+  event.xfer_complete.ep_addr = ep_addr;
+  event.xfer_complete.result = result;
+  event.xfer_complete.len = xferred_bytes;
+
 
   hcd_event_handler(&event, in_isr);
 }
diff --git a/src/host/hub.c b/src/host/hub.c
index 9e546f6f..5c0fd916 100644
--- a/src/host/hub.c
+++ b/src/host/hub.c
@@ -169,7 +169,7 @@ bool hub_port_get_status(uint8_t hub_addr, uint8_t hub_port, void* resp,
   };
 
   TU_LOG2("HUB Get Port Status: addr = %u port = %u\r\n", hub_addr, hub_port);
-  TU_ASSERT( tuh_control_xfer(&xfer) );
+  TU_VERIFY( tuh_control_xfer(&xfer) );
   return true;
 }
 
@@ -332,7 +332,11 @@ bool hub_xfer_cb(uint8_t dev_addr, uint8_t ep_addr, xfer_result_t result, uint32
   {
     if ( tu_bit_test(p_hub->status_change, port) )
     {
-      hub_port_get_status(dev_addr, port, &p_hub->port_status, connection_get_status_complete, 0);
+      if (hub_port_get_status(dev_addr, port, &p_hub->port_status, connection_get_status_complete, 0) == false)
+      {
+        //Hub status control transfer failed, retry
+        hub_edpt_status_xfer(dev_addr);
+      }
       break;
     }
   }
diff --git a/src/host/usbh.c b/src/host/usbh.c
index a600f709..4807d20b 100644
--- a/src/host/usbh.c
+++ b/src/host/usbh.c
@@ -1100,6 +1100,12 @@ uint8_t tuh_descriptor_get_serial_string_sync(uint8_t daddr, uint16_t language_i
 //
 //--------------------------------------------------------------------+
 
+TU_ATTR_ALWAYS_INLINE
+static inline bool is_hub_addr(uint8_t daddr)
+{
+  return (CFG_TUH_HUB > 0) && (daddr > CFG_TUH_DEVICE_MAX);
+}
+
 // a device unplugged from rhport:hub_addr:hub_port
 static void process_device_unplugged(uint8_t rhport, uint8_t hub_addr, uint8_t hub_port)
 {
@@ -1112,14 +1118,23 @@ static void process_device_unplugged(uint8_t rhport, uint8_t hub_addr, uint8_t h
 
     // TODO Hub multiple level
     if (dev->rhport == rhport   &&
-        (hub_addr == 0 || dev->hub_addr == hub_addr) && // hub_addr == 0 & hub_port == 0 means roothub
-        (hub_port == 0 || dev->hub_port == hub_port) &&
+        (hub_addr == 0 || dev->hub_addr == hub_addr) && // hub_addr = 0 means roothub
+        (hub_port == 0 || dev->hub_port == hub_port) && // hub_port = 0 means all devices of downstream hub
         dev->connected)
     {
       TU_LOG2("  Address = %u\r\n", dev_addr);
 
-      // Invoke callback before close driver
-      if (tuh_umount_cb) tuh_umount_cb(dev_addr);
+      if (is_hub_addr(dev_addr))
+      {
+        TU_LOG(USBH_DBG_LVL, "HUB address = %u is unmounted\r\n", dev_addr);
+        // If the device itself is a usb hub, unplug downstream devices.
+        // FIXME un-roll recursive calls to prevent potential stack overflow
+        process_device_unplugged(rhport, dev_addr, 0);
+      }else
+      {
+        // Invoke callback before closing driver
+        if (tuh_umount_cb) tuh_umount_cb(dev_addr);
+      }
 
       // Close class driver
       for (uint8_t drv_id = 0; drv_id < USBH_CLASS_DRIVER_COUNT; drv_id++)
@@ -1402,12 +1417,6 @@ static bool enum_new_device(hcd_event_t* event)
   return true;
 }
 
-TU_ATTR_ALWAYS_INLINE
-static inline bool is_hub_addr(uint8_t daddr)
-{
-  return daddr > CFG_TUH_DEVICE_MAX;
-}
-
 static uint8_t get_new_address(bool is_hub)
 {
   uint8_t start;
@@ -1520,40 +1529,31 @@ static bool _parse_configuration_descriptor(uint8_t dev_addr, tusb_desc_configur
     uint16_t const drv_len = tu_desc_get_interface_total_len(desc_itf, assoc_itf_count, desc_end-p_desc);
     TU_ASSERT(drv_len >= sizeof(tusb_desc_interface_t));
 
-    if (desc_itf->bInterfaceClass == TUSB_CLASS_HUB && dev->hub_addr != 0)
+    // Find driver for this interface
+    uint8_t drv_id;
+    for (drv_id = 0; drv_id < USBH_CLASS_DRIVER_COUNT; drv_id++)
     {
-      // TODO Attach hub to Hub is not currently supported
-      // skip this interface
-      TU_LOG(USBH_DBG_LVL, "Only 1 level of HUB is supported\r\n");
-    }
-    else
-    {
-      // Find driver for this interface
-      uint8_t drv_id;
-      for (drv_id = 0; drv_id < USBH_CLASS_DRIVER_COUNT; drv_id++)
+      usbh_class_driver_t const * driver = &usbh_class_drivers[drv_id];
+
+      if ( driver->open(dev->rhport, dev_addr, desc_itf, drv_len) )
       {
-        usbh_class_driver_t const * driver = &usbh_class_drivers[drv_id];
+        // open successfully
+        TU_LOG2("  %s opened\r\n", driver->name);
 
-        if ( driver->open(dev->rhport, dev_addr, desc_itf, drv_len) )
+        // bind (associated) interfaces to found driver
+        for(uint8_t i=0; i<assoc_itf_count; i++)
         {
-          // open successfully
-          TU_LOG2("  %s opened\r\n", driver->name);
+          uint8_t const itf_num = desc_itf->bInterfaceNumber+i;
 
-          // bind (associated) interfaces to found driver
-          for(uint8_t i=0; i<assoc_itf_count; i++)
-          {
-            uint8_t const itf_num = desc_itf->bInterfaceNumber+i;
-
-            // Interface number must not be used already
-            TU_ASSERT( DRVID_INVALID == dev->itf2drv[itf_num] );
-            dev->itf2drv[itf_num] = drv_id;
-          }
-
-          // bind all endpoints to found driver
-          tu_edpt_bind_driver(dev->ep2drv, desc_itf, drv_len, drv_id);
-
-          break; // exit driver find loop
+          // Interface number must not be used already
+          TU_ASSERT( DRVID_INVALID == dev->itf2drv[itf_num] );
+          dev->itf2drv[itf_num] = drv_id;
         }
+
+        // bind all endpoints to found driver
+        tu_edpt_bind_driver(dev->ep2drv, desc_itf, drv_len, drv_id);
+
+        break; // exit driver find loop
       }
 
       if( drv_id >= USBH_CLASS_DRIVER_COUNT )
@@ -1593,10 +1593,10 @@ void usbh_driver_set_config_complete(uint8_t dev_addr, uint8_t itf_num)
   {
     enum_full_complete();
 
-#if CFG_TUH_HUB
-    // skip device mount callback for hub
-    if ( !is_hub_addr(dev_addr) )
-#endif
+    if (is_hub_addr(dev_addr))
+    {
+      TU_LOG(USBH_DBG_LVL, "HUB address = %u is mounted\r\n", dev_addr);
+    }else
     {
       // Invoke callback if available
       if (tuh_mount_cb) tuh_mount_cb(dev_addr);