[PATCH 3.2 061/115] usb: renesas_usbhs: disable TX IRQ before starting TX DMAC transfer

[Ben Hutchings]

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

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

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>

commit 6490865c67825277b29638e839850882600b48ec upstream.

This patch adds a code to surely disable TX IRQ of the pipe before
starting TX DMAC transfer. Otherwise, a lot of unnecessary TX IRQs
may happen in rare cases when DMAC is used.

Fixes: e73a989 ("usb: renesas_usbhs: add DMAEngine support")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/renesas_usbhs/fifo.c | 1 +
 1 file changed, 1 insertion(+)

--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -932,6 +932,7 @@ static int usbhsf_dma_try_pop(struct usb
 
 	pkt->trans = len;
 
+	usbhsf_tx_irq_ctrl(pipe, 0);
 	tasklet_init(&fifo->tasklet,
 		     usbhsf_dma_prepare_tasklet,
 		     (unsigned long)pkt);