[PATCH 4.5 094/124] usb: renesas_usbhs: disable TX IRQ before starting TX DMAC transfer

From: Greg Kroah-Hartman
Date: Sun Apr 17 2016 - 23:11:45 EST


4.5-stable 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>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
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
@@ -890,6 +890,7 @@ static int usbhsf_dma_prepare_push(struc

pkt->trans = len;

+ usbhsf_tx_irq_ctrl(pipe, 0);
INIT_WORK(&pkt->work, xfer_work);
schedule_work(&pkt->work);