[patch 2.6.29+] musb: use dma mode 1 for TX if transfer size equals maxpacket (v2)

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From: Anand Gadiyar <gadiyar@xxxxxx>

Currently, with Inventra DMA, we use Mode 0 if transfer size is less
than or equal to the endpoint's maxpacket size.  This requires that
we explicitly set TXPKTRDY for that transfer.

However the musb_g_tx code will not set TXPKTRDY twice if the last
transfer is exactly equal to maxpacket, even if request->zero is set.
Using Mode 1 will solve this; a better fix might be in musb_g_tx().

Without this change, musb will not correctly send out a ZLP if the
last transfer is the maxpacket size and request->zero is set. 

Signed-off-by: Anand Gadiyar <gadiyar@xxxxxx>
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
---
Comment update.

 drivers/usb/musb/musb_gadget.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -310,7 +310,7 @@ static void txstate(struct musb *musb, s
 			/* setup DMA, then program endpoint CSR */
 			request_size = min(request->length,
 						musb_ep->dma->max_len);
-			if (request_size <= musb_ep->packet_sz)
+			if (request_size < musb_ep->packet_sz)
 				musb_ep->dma->desired_mode = 0;
 			else
 				musb_ep->dma->desired_mode = 1;

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