[PATCH 3.16 094/136] usb: gadget: udc: atmel: Fix interrupt storm in FIFO mode.

[Ben Hutchings]

3.16.80-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Cristian Birsan <cristian.birsan@xxxxxxxxxxxxx>

commit ba3a1a915c49cc3023e4ddfc88f21e7514e82aa4 upstream.

Fix interrupt storm generated by endpoints when working in FIFO mode.
The TX_COMPLETE interrupt is used only by control endpoints processing.
Do not enable it for other types of endpoints.

Fixes: 914a3f3b3754 ("USB: add atmel_usba_udc driver")
Signed-off-by: Cristian Birsan <cristian.birsan@xxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/gadget/atmel_usba_udc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/usb/gadget/atmel_usba_udc.c
+++ b/drivers/usb/gadget/atmel_usba_udc.c
@@ -392,9 +392,11 @@ static void submit_request(struct usba_e
 		next_fifo_transaction(ep, req);
 		if (req->last_transaction) {
 			usba_ep_writel(ep, CTL_DIS, USBA_TX_PK_RDY);
-			usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
+			if (ep_is_control(ep))
+				usba_ep_writel(ep, CTL_ENB, USBA_TX_COMPLETE);
 		} else {
-			usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
+			if (ep_is_control(ep))
+				usba_ep_writel(ep, CTL_DIS, USBA_TX_COMPLETE);
 			usba_ep_writel(ep, CTL_ENB, USBA_TX_PK_RDY);
 		}
 	}