usb: ks_bridge: Fix memory leaks in the driver.

This change addresses two memory leaks:-
1) misc device is not getting deregistered during device
disconnect. Hence call misc_deregister() in disconnect.

2) Driver returns without freeing previous instances of
the driver data structure if memory allocation fails. Hence
free up memory allocated for ks_bridge structure.

Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
(cherry picked from commit da86bd2faa9cfbf065c7a1f0adba124d7e8335e0)

Conflicts:

	drivers/usb/misc/ks_bridge.c

Change-Id: I5e1c357fa29b455bae5f3dc71b4d65d5cc216bb3
Signed-off-by: Sudhir Sharma <sudsha@codeaurora.org>
diff --git a/drivers/usb/misc/ks_bridge.c b/drivers/usb/misc/ks_bridge.c
index 591440d..0b35f0d 100644
--- a/drivers/usb/misc/ks_bridge.c
+++ b/drivers/usb/misc/ks_bridge.c
@@ -58,6 +58,7 @@
 	struct list_head	to_mdm_list;
 	struct list_head	to_ks_list;
 	wait_queue_head_t	ks_wait_q;
+	struct miscdevice	*fs_dev;
 
 	/* usb specific */
 	struct usb_device	*udev;
@@ -530,7 +531,6 @@
 	struct usb_endpoint_descriptor	*ep_desc;
 	int				i;
 	struct ks_bridge		*ksb;
-	struct miscdevice		*fs_dev;
 
 	ifc_num = ifc->cur_altsetting->desc.bInterfaceNumber;
 
@@ -584,8 +584,8 @@
 
 	dbg_log_event(ksb, "PID-ATT", id->idProduct, 0);
 
-	fs_dev = (struct miscdevice *)id->driver_info;
-	misc_register(fs_dev);
+	ksb->fs_dev = (struct miscdevice *)id->driver_info;
+	misc_register(ksb->fs_dev);
 
 	ifc->needs_remote_wakeup = 1;
 	usb_enable_autosuspend(ksb->udev);
@@ -630,8 +630,9 @@
 	wake_up(&ksb->ks_wait_q);
 	cancel_work_sync(&ksb->to_mdm_work);
 
-	usb_kill_anchored_urbs(&ksb->submitted);
+	misc_deregister(ksb->fs_dev);
 
+	usb_kill_anchored_urbs(&ksb->submitted);
 	spin_lock_irqsave(&ksb->lock, flags);
 	while (!list_empty(&ksb->to_ks_list)) {
 		pkt = list_first_entry(&ksb->to_ks_list,
@@ -712,7 +713,8 @@
 		ksb = kzalloc(sizeof(struct ks_bridge), GFP_KERNEL);
 		if (!ksb) {
 			pr_err("unable to allocat mem for ks_bridge");
-			return -ENOMEM;
+			ret =  -ENOMEM;
+			goto dev_free;
 		}
 		__ksb[i] = ksb;