usb: musb: gadget: fix DMA length for OUT transfer

DMA length should not go beyond the availabe space of request buffer,
so fix it.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Anand Gadiyar <gadiyar@ti.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Anand Gadiyar <gadiyar@ti.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index 176e127..f3ee04f 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -659,10 +659,11 @@
 				if (request->actual < request->length) {
 					int transfer_size = 0;
 #ifdef USE_MODE1
-					transfer_size = min(request->length,
+					transfer_size = min(request->length - request->actual,
 							channel->max_len);
 #else
-					transfer_size = len;
+					transfer_size = min(request->length - request->actual,
+							(unsigned)len);
 #endif
 					if (transfer_size <= musb_ep->packet_sz)
 						musb_ep->dma->desired_mode = 0;