USB: musb: correct DMA address for tx

Since a DMA transfer may need to be kicked off several times to complete,
the DMA start must include the length that has already been transferred.

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Felipe Balbi <felipe.balbi@nokia.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 e164999..ac30698 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -319,7 +319,7 @@
 			use_dma = use_dma && c->channel_program(
 					musb_ep->dma, musb_ep->packet_sz,
 					musb_ep->dma->desired_mode,
-					request->dma, request_size);
+					request->dma + request->actual, request_size);
 			if (use_dma) {
 				if (musb_ep->dma->desired_mode == 0) {
 					/*