1 files changed, 36 insertions, 3 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 265c2f675d0..0c2bc00cc12 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -30,6 +30,12 @@
 
 #include "usb.h"
 
+#ifdef CONFIG_ARCH_U8500
+#define MAX_TOPO_LEVEL_U8500 2
+#define MAX_USB_DEVICE_U8500 8
+int usb_device_count;
+#endif
+
 /* if we are in debug mode, always announce new devices */
 #ifdef DEBUG
 #ifndef CONFIG_USB_ANNOUNCE_NEW_DEVICES
@@ -1302,11 +1308,20 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	if (!hub_is_superspeed(hdev) || !hdev->parent)
 		usb_enable_autosuspend(hdev);
 
+#ifdef CONFIG_ARCH_U8500
+	if (hdev->level > MAX_TOPO_LEVEL_U8500) {
+		dev_err(&intf->dev,
+			"Unsupported bus topology: > %d "
+			" hub nesting\n", MAX_TOPO_LEVEL_U8500);
+		return -E2BIG;
+	}
+#else
 	if (hdev->level == MAX_TOPO_LEVEL) {
 		dev_err(&intf->dev,
 			"Unsupported bus topology: hub nested too deep\n");
 		return -E2BIG;
 	}
+#endif
 
 #ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
 	if (hdev->parent) {
@@ -1588,12 +1603,14 @@ static void choose_devnum(struct usb_device *udev)
 		 * bus->devnum_next. */
 		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
 					    bus->devnum_next);
-		if (devnum >= 128)
+		/* Due to Hardware bugs we need to reserve a device address
+		 * for flushing of endpoints. */
+		if (devnum >= 127)
 			devnum = find_next_zero_bit(bus->devmap.devicemap,
 						    128, 1);
-		bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
+		bus->devnum_next = devnum >= 126 ? 1 : devnum + 1;
 	}
-	if (devnum < 128) {
+	if (devnum < 127) {
 		set_bit(devnum, bus->devmap.devicemap);
 		udev->devnum = devnum;
 	}
@@ -3320,6 +3337,22 @@ static void hub_port_connect_change(struct usb_hub *hub, int port1,
 			goto loop;
 		}
 
+#ifdef CONFIG_ARCH_U8500
+		if (hdev->parent == NULL)
+				usb_device_count = 1;
+
+		if (usb_device_count > MAX_USB_DEVICE_U8500) {
+
+				dev_err(&udev->dev,
+					"device connected is more than %d\n",
+					MAX_USB_DEVICE_U8500);
+
+				status = -ENOTCONN;     /* Don't retry */
+				goto loop;
+		}
+#endif
+
+
 		/* reset (non-USB 3.0 devices) and get descriptor */
 		status = hub_port_init(hub, udev, port1, i);
 		if (status < 0)