releases/3.2.14/usb-gadgetfs-return-number-of-bytes-on-ep0-read-request.patch

From 85b4b3c8c189e0159101f7628a71411af072ff69 Mon Sep 17 00:00:00 2001
From: Thomas Faber <thfabba@gmx.de>
Date: Fri, 2 Mar 2012 09:41:50 +0100
Subject: usb: gadgetfs: return number of bytes on ep0 read request

From: Thomas Faber <thfabba@gmx.de>

commit 85b4b3c8c189e0159101f7628a71411af072ff69 upstream.

A read from GadgetFS endpoint 0 during the data stage of a control
request would always return 0 on success (as returned by
wait_event_interruptible) despite having written data into the user
buffer.
This patch makes it correctly set the return value to the number of
bytes read.

Signed-off-by: Thomas Faber <thfabba@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/gadget/inode.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -1043,6 +1043,8 @@ ep0_read (struct file *fd, char __user *
 // FIXME don't call this with the spinlock held ...
 				if (copy_to_user (buf, dev->req->buf, len))
 					retval = -EFAULT;
+				else
+					retval = len;
 				clean_req (dev->gadget->ep0, dev->req);
 				/* NOTE userspace can't yet choose to stall */
 			}