From df36eaab95ad099cd37a11fd54b89ac9d575a449 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver@neukum.org>
Date: Thu, 25 Oct 2007 16:05:53 +0200
Subject: [PATCH] --- yaml --- r: 72588 b: refs/heads/master c:
 d5d1ceac2a47645780bd07fd7a670b14c4d995db h: refs/heads/master v: v3

---
 [refs]                          |  2 +-
 trunk/drivers/usb/misc/usblcd.c | 11 ++++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 206ef426cb07..5160a1e40871 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 78663ecc344b4694dd737deb682e81312a0684b6
+refs/heads/master: d5d1ceac2a47645780bd07fd7a670b14c4d995db
diff --git a/trunk/drivers/usb/misc/usblcd.c b/trunk/drivers/usb/misc/usblcd.c
index 719842032712..20777d01db62 100644
--- a/trunk/drivers/usb/misc/usblcd.c
+++ b/trunk/drivers/usb/misc/usblcd.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
+#include <linux/mutex.h>
 #include <asm/uaccess.h>
 #include <linux/usb.h>
 
@@ -34,6 +35,8 @@ static struct usb_device_id id_table [] = {
 };
 MODULE_DEVICE_TABLE (usb, id_table);
 
+static DEFINE_MUTEX(open_disc_mutex);
+
 
 struct usb_lcd {
 	struct usb_device *	udev;			/* init: probe_lcd */
@@ -79,12 +82,16 @@ static int lcd_open(struct inode *inode, struct file *file)
 		return -ENODEV;
 	}
 
+	mutex_lock(&open_disc_mutex);
 	dev = usb_get_intfdata(interface);
-	if (!dev)
+	if (!dev) {
+		mutex_unlock(&open_disc_mutex);
 		return -ENODEV;
+	}
 
 	/* increment our usage count for the device */
 	kref_get(&dev->kref);
+	mutex_unlock(&open_disc_mutex);
 
 	/* grab a power reference */
 	r = usb_autopm_get_interface(interface);
@@ -393,8 +400,10 @@ static void lcd_disconnect(struct usb_interface *interface)
 	struct usb_lcd *dev;
         int minor = interface->minor;
 
+	mutex_lock(&open_disc_mutex);
         dev = usb_get_intfdata(interface);
         usb_set_intfdata(interface, NULL);
+	mutex_unlock(&open_disc_mutex);
 
         /* give back our minor */
         usb_deregister_dev(interface, &lcd_class);