1 files changed, 14 insertions, 2 deletions

diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c
index 68697f596066..64a4112068fc 100644
--- a/drivers/usb/gadget/function/f_printer.c
+++ b/drivers/usb/gadget/function/f_printer.c
@@ -31,6 +31,7 @@
 #include <linux/types.h>
 #include <linux/ctype.h>
 #include <linux/cdev.h>
+#include <linux/kref.h>
 
 #include <asm/byteorder.h>
 #include <linux/io.h>
@@ -64,7 +65,7 @@ struct printer_dev {
 	struct usb_gadget	*gadget;
 	s8			interface;
 	struct usb_ep		*in_ep, *out_ep;
-
+	struct kref             kref;
 	struct list_head	rx_reqs;	/* List of free RX structs */
 	struct list_head	rx_reqs_active;	/* List of Active RX xfers */
 	struct list_head	rx_buffers;	/* List of completed xfers */
@@ -218,6 +219,13 @@ static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
 
 /*-------------------------------------------------------------------------*/
 
+static void printer_dev_free(struct kref *kref)
+{
+	struct printer_dev *dev = container_of(kref, struct printer_dev, kref);
+
+	kfree(dev);
+}
+
 static struct usb_request *
 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
 {
@@ -353,6 +361,7 @@ printer_open(struct inode *inode, struct file *fd)
 
 	spin_unlock_irqrestore(&dev->lock, flags);
 
+	kref_get(&dev->kref);
 	DBG(dev, "printer_open returned %x\n", ret);
 	return ret;
 }
@@ -370,6 +379,7 @@ printer_close(struct inode *inode, struct file *fd)
 	dev->printer_status &= ~PRINTER_SELECTED;
 	spin_unlock_irqrestore(&dev->lock, flags);
 
+	kref_put(&dev->kref, printer_dev_free);
 	DBG(dev, "printer_close\n");
 
 	return 0;
@@ -1386,7 +1396,8 @@ static void gprinter_free(struct usb_function *f)
 	struct f_printer_opts *opts;
 
 	opts = container_of(f->fi, struct f_printer_opts, func_inst);
-	kfree(dev);
+
+	kref_put(&dev->kref, printer_dev_free);
 	mutex_lock(&opts->lock);
 	--opts->refcnt;
 	mutex_unlock(&opts->lock);
@@ -1455,6 +1466,7 @@ static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
 		return ERR_PTR(-ENOMEM);
 	}
 
+	kref_init(&dev->kref);
 	++opts->refcnt;
 	dev->minor = opts->minor;
 	dev->pnp_string = opts->pnp_string;