From david-b@pacbell.net Wed Aug 30 13:25:15 2006
From: David Brownell <david-b@pacbell.net>
To: Greg KH <greg@kroah.com>
Subject: USB: ethernet gadget avoids zlps for musb_hdrc
Date: Wed, 30 Aug 2006 13:24:56 -0700
Cc: Tony Lindgren <tony@atomide.com>
Content-Disposition: inline
Message-Id: <200608301324.57297.david-b@pacbell.net>

For systems using the Mentor HDRC controllers we get better TX DMA throughput
if we can avoid falling back to PIO to write zero length packets ... so tell
the driver to avoid ZLPs.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/usb/gadget/ether.c |    3 +++
 1 file changed, 3 insertions(+)

--- gregkh-2.6.orig/drivers/usb/gadget/ether.c
+++ gregkh-2.6/drivers/usb/gadget/ether.c
@@ -2230,6 +2230,9 @@ eth_bind (struct usb_gadget *gadget)
 	if (gadget_is_pxa (gadget)) {
 		/* pxa doesn't support altsettings */
 		cdc = 0;
+	} else if (gadget_is_musbhdrc(gadget)) {
+		/* reduce tx dma overhead by avoiding special cases */
+		zlp = 0;
 	} else if (gadget_is_sh(gadget)) {
 		/* sh doesn't support multiple interfaces or configs */
 		cdc = 0;